4182 lines
138 KiB
C
4182 lines
138 KiB
C
/* Target-struct-independent code to start (run) and stop an inferior
|
||
process.
|
||
|
||
Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
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1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free
|
||
Software Foundation, Inc.
|
||
|
||
This file is part of GDB.
|
||
|
||
This program is free software; you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 2 of the License, or
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with this program; if not, write to the Free Software
|
||
Foundation, Inc., 59 Temple Place - Suite 330,
|
||
Boston, MA 02111-1307, USA. */
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||
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#include "defs.h"
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||
#include "gdb_string.h"
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#include <ctype.h>
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#include "symtab.h"
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#include "frame.h"
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||
#include "inferior.h"
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||
#include "breakpoint.h"
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#include "gdb_wait.h"
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#include "gdbcore.h"
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#include "gdbcmd.h"
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#include "cli/cli-script.h"
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#include "target.h"
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||
#include "gdbthread.h"
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#include "annotate.h"
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#include "symfile.h"
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#include "top.h"
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#include <signal.h>
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#include "inf-loop.h"
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#include "regcache.h"
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#include "value.h"
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#include "observer.h"
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#include "language.h"
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#include "gdb_assert.h"
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/* Prototypes for local functions */
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static void signals_info (char *, int);
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static void handle_command (char *, int);
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static void sig_print_info (enum target_signal);
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static void sig_print_header (void);
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||
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static void resume_cleanups (void *);
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||
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static int hook_stop_stub (void *);
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static void delete_breakpoint_current_contents (void *);
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static int restore_selected_frame (void *);
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static void build_infrun (void);
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static int follow_fork (void);
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static void set_schedlock_func (char *args, int from_tty,
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struct cmd_list_element *c);
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||
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struct execution_control_state;
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||
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static int currently_stepping (struct execution_control_state *ecs);
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||
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static void xdb_handle_command (char *args, int from_tty);
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static int prepare_to_proceed (void);
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void _initialize_infrun (void);
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int inferior_ignoring_startup_exec_events = 0;
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int inferior_ignoring_leading_exec_events = 0;
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/* When set, stop the 'step' command if we enter a function which has
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no line number information. The normal behavior is that we step
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over such function. */
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int step_stop_if_no_debug = 0;
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/* In asynchronous mode, but simulating synchronous execution. */
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int sync_execution = 0;
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/* wait_for_inferior and normal_stop use this to notify the user
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when the inferior stopped in a different thread than it had been
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running in. */
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static ptid_t previous_inferior_ptid;
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/* This is true for configurations that may follow through execl() and
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similar functions. At present this is only true for HP-UX native. */
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#ifndef MAY_FOLLOW_EXEC
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#define MAY_FOLLOW_EXEC (0)
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#endif
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static int may_follow_exec = MAY_FOLLOW_EXEC;
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/* If the program uses ELF-style shared libraries, then calls to
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functions in shared libraries go through stubs, which live in a
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table called the PLT (Procedure Linkage Table). The first time the
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function is called, the stub sends control to the dynamic linker,
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which looks up the function's real address, patches the stub so
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that future calls will go directly to the function, and then passes
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control to the function.
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If we are stepping at the source level, we don't want to see any of
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this --- we just want to skip over the stub and the dynamic linker.
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The simple approach is to single-step until control leaves the
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dynamic linker.
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||
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However, on some systems (e.g., Red Hat's 5.2 distribution) the
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dynamic linker calls functions in the shared C library, so you
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can't tell from the PC alone whether the dynamic linker is still
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running. In this case, we use a step-resume breakpoint to get us
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past the dynamic linker, as if we were using "next" to step over a
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function call.
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IN_SOLIB_DYNSYM_RESOLVE_CODE says whether we're in the dynamic
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linker code or not. Normally, this means we single-step. However,
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if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
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address where we can place a step-resume breakpoint to get past the
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linker's symbol resolution function.
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||
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||
IN_SOLIB_DYNSYM_RESOLVE_CODE can generally be implemented in a
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pretty portable way, by comparing the PC against the address ranges
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of the dynamic linker's sections.
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||
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SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
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it depends on internal details of the dynamic linker. It's usually
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not too hard to figure out where to put a breakpoint, but it
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certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
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sanity checking. If it can't figure things out, returning zero and
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getting the (possibly confusing) stepping behavior is better than
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signalling an error, which will obscure the change in the
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inferior's state. */
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||
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#ifndef IN_SOLIB_DYNSYM_RESOLVE_CODE
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#define IN_SOLIB_DYNSYM_RESOLVE_CODE(pc) 0
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#endif
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/* This function returns TRUE if pc is the address of an instruction
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that lies within the dynamic linker (such as the event hook, or the
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dld itself).
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This function must be used only when a dynamic linker event has
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been caught, and the inferior is being stepped out of the hook, or
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undefined results are guaranteed. */
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||
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#ifndef SOLIB_IN_DYNAMIC_LINKER
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#define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
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#endif
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/* On MIPS16, a function that returns a floating point value may call
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a library helper function to copy the return value to a floating point
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register. The IGNORE_HELPER_CALL macro returns non-zero if we
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should ignore (i.e. step over) this function call. */
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#ifndef IGNORE_HELPER_CALL
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#define IGNORE_HELPER_CALL(pc) 0
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#endif
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/* On some systems, the PC may be left pointing at an instruction that won't
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actually be executed. This is usually indicated by a bit in the PSW. If
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we find ourselves in such a state, then we step the target beyond the
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nullified instruction before returning control to the user so as to avoid
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confusion. */
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#ifndef INSTRUCTION_NULLIFIED
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#define INSTRUCTION_NULLIFIED 0
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#endif
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/* We can't step off a permanent breakpoint in the ordinary way, because we
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can't remove it. Instead, we have to advance the PC to the next
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instruction. This macro should expand to a pointer to a function that
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does that, or zero if we have no such function. If we don't have a
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definition for it, we have to report an error. */
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#ifndef SKIP_PERMANENT_BREAKPOINT
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#define SKIP_PERMANENT_BREAKPOINT (default_skip_permanent_breakpoint)
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static void
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default_skip_permanent_breakpoint (void)
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{
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error ("\
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The program is stopped at a permanent breakpoint, but GDB does not know\n\
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how to step past a permanent breakpoint on this architecture. Try using\n\
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a command like `return' or `jump' to continue execution.");
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}
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#endif
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/* Convert the #defines into values. This is temporary until wfi control
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flow is completely sorted out. */
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#ifndef HAVE_STEPPABLE_WATCHPOINT
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#define HAVE_STEPPABLE_WATCHPOINT 0
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#else
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#undef HAVE_STEPPABLE_WATCHPOINT
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#define HAVE_STEPPABLE_WATCHPOINT 1
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#endif
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#ifndef CANNOT_STEP_HW_WATCHPOINTS
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#define CANNOT_STEP_HW_WATCHPOINTS 0
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#else
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#undef CANNOT_STEP_HW_WATCHPOINTS
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#define CANNOT_STEP_HW_WATCHPOINTS 1
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#endif
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/* Tables of how to react to signals; the user sets them. */
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static unsigned char *signal_stop;
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static unsigned char *signal_print;
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static unsigned char *signal_program;
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#define SET_SIGS(nsigs,sigs,flags) \
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do { \
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int signum = (nsigs); \
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while (signum-- > 0) \
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if ((sigs)[signum]) \
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(flags)[signum] = 1; \
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} while (0)
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#define UNSET_SIGS(nsigs,sigs,flags) \
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do { \
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int signum = (nsigs); \
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while (signum-- > 0) \
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if ((sigs)[signum]) \
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(flags)[signum] = 0; \
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} while (0)
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/* Value to pass to target_resume() to cause all threads to resume */
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#define RESUME_ALL (pid_to_ptid (-1))
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/* Command list pointer for the "stop" placeholder. */
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static struct cmd_list_element *stop_command;
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/* Nonzero if breakpoints are now inserted in the inferior. */
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static int breakpoints_inserted;
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/* Function inferior was in as of last step command. */
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static struct symbol *step_start_function;
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/* Nonzero if we are expecting a trace trap and should proceed from it. */
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static int trap_expected;
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#ifdef SOLIB_ADD
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/* Nonzero if we want to give control to the user when we're notified
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of shared library events by the dynamic linker. */
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static int stop_on_solib_events;
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#endif
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#ifdef HP_OS_BUG
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/* Nonzero if the next time we try to continue the inferior, it will
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step one instruction and generate a spurious trace trap.
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This is used to compensate for a bug in HP-UX. */
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static int trap_expected_after_continue;
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#endif
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/* Nonzero means expecting a trace trap
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and should stop the inferior and return silently when it happens. */
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int stop_after_trap;
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/* Nonzero means expecting a trap and caller will handle it themselves.
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It is used after attach, due to attaching to a process;
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when running in the shell before the child program has been exec'd;
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and when running some kinds of remote stuff (FIXME?). */
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enum stop_kind stop_soon;
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/* Nonzero if proceed is being used for a "finish" command or a similar
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situation when stop_registers should be saved. */
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int proceed_to_finish;
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/* Save register contents here when about to pop a stack dummy frame,
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if-and-only-if proceed_to_finish is set.
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Thus this contains the return value from the called function (assuming
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values are returned in a register). */
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struct regcache *stop_registers;
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/* Nonzero if program stopped due to error trying to insert breakpoints. */
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static int breakpoints_failed;
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/* Nonzero after stop if current stack frame should be printed. */
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static int stop_print_frame;
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static struct breakpoint *step_resume_breakpoint = NULL;
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static struct breakpoint *through_sigtramp_breakpoint = NULL;
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/* On some platforms (e.g., HP-UX), hardware watchpoints have bad
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interactions with an inferior that is running a kernel function
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(aka, a system call or "syscall"). wait_for_inferior therefore
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may have a need to know when the inferior is in a syscall. This
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is a count of the number of inferior threads which are known to
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currently be running in a syscall. */
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static int number_of_threads_in_syscalls;
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/* This is a cached copy of the pid/waitstatus of the last event
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returned by target_wait()/target_wait_hook(). This information is
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||
returned by get_last_target_status(). */
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||
static ptid_t target_last_wait_ptid;
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||
static struct target_waitstatus target_last_waitstatus;
|
||
|
||
/* This is used to remember when a fork, vfork or exec event
|
||
was caught by a catchpoint, and thus the event is to be
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followed at the next resume of the inferior, and not
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immediately. */
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static struct
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{
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enum target_waitkind kind;
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struct
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{
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int parent_pid;
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int child_pid;
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}
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fork_event;
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char *execd_pathname;
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}
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pending_follow;
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||
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||
static const char follow_fork_mode_child[] = "child";
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||
static const char follow_fork_mode_parent[] = "parent";
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||
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||
static const char *follow_fork_mode_kind_names[] = {
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follow_fork_mode_child,
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follow_fork_mode_parent,
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NULL
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||
};
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||
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static const char *follow_fork_mode_string = follow_fork_mode_parent;
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||
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||
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static int
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follow_fork (void)
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{
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||
int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
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return target_follow_fork (follow_child);
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}
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||
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||
void
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||
follow_inferior_reset_breakpoints (void)
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||
{
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||
/* Was there a step_resume breakpoint? (There was if the user
|
||
did a "next" at the fork() call.) If so, explicitly reset its
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||
thread number.
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||
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step_resumes are a form of bp that are made to be per-thread.
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||
Since we created the step_resume bp when the parent process
|
||
was being debugged, and now are switching to the child process,
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||
from the breakpoint package's viewpoint, that's a switch of
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"threads". We must update the bp's notion of which thread
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it is for, or it'll be ignored when it triggers. */
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||
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if (step_resume_breakpoint)
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breakpoint_re_set_thread (step_resume_breakpoint);
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||
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||
/* Reinsert all breakpoints in the child. The user may have set
|
||
breakpoints after catching the fork, in which case those
|
||
were never set in the child, but only in the parent. This makes
|
||
sure the inserted breakpoints match the breakpoint list. */
|
||
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breakpoint_re_set ();
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insert_breakpoints ();
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||
}
|
||
|
||
/* EXECD_PATHNAME is assumed to be non-NULL. */
|
||
|
||
static void
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follow_exec (int pid, char *execd_pathname)
|
||
{
|
||
int saved_pid = pid;
|
||
struct target_ops *tgt;
|
||
|
||
if (!may_follow_exec)
|
||
return;
|
||
|
||
/* This is an exec event that we actually wish to pay attention to.
|
||
Refresh our symbol table to the newly exec'd program, remove any
|
||
momentary bp's, etc.
|
||
|
||
If there are breakpoints, they aren't really inserted now,
|
||
since the exec() transformed our inferior into a fresh set
|
||
of instructions.
|
||
|
||
We want to preserve symbolic breakpoints on the list, since
|
||
we have hopes that they can be reset after the new a.out's
|
||
symbol table is read.
|
||
|
||
However, any "raw" breakpoints must be removed from the list
|
||
(e.g., the solib bp's), since their address is probably invalid
|
||
now.
|
||
|
||
And, we DON'T want to call delete_breakpoints() here, since
|
||
that may write the bp's "shadow contents" (the instruction
|
||
value that was overwritten witha TRAP instruction). Since
|
||
we now have a new a.out, those shadow contents aren't valid. */
|
||
update_breakpoints_after_exec ();
|
||
|
||
/* If there was one, it's gone now. We cannot truly step-to-next
|
||
statement through an exec(). */
|
||
step_resume_breakpoint = NULL;
|
||
step_range_start = 0;
|
||
step_range_end = 0;
|
||
|
||
/* If there was one, it's gone now. */
|
||
through_sigtramp_breakpoint = NULL;
|
||
|
||
/* What is this a.out's name? */
|
||
printf_unfiltered ("Executing new program: %s\n", execd_pathname);
|
||
|
||
/* We've followed the inferior through an exec. Therefore, the
|
||
inferior has essentially been killed & reborn. */
|
||
|
||
/* First collect the run target in effect. */
|
||
tgt = find_run_target ();
|
||
/* If we can't find one, things are in a very strange state... */
|
||
if (tgt == NULL)
|
||
error ("Could find run target to save before following exec");
|
||
|
||
gdb_flush (gdb_stdout);
|
||
target_mourn_inferior ();
|
||
inferior_ptid = pid_to_ptid (saved_pid);
|
||
/* Because mourn_inferior resets inferior_ptid. */
|
||
push_target (tgt);
|
||
|
||
/* That a.out is now the one to use. */
|
||
exec_file_attach (execd_pathname, 0);
|
||
|
||
/* And also is where symbols can be found. */
|
||
symbol_file_add_main (execd_pathname, 0);
|
||
|
||
/* Reset the shared library package. This ensures that we get
|
||
a shlib event when the child reaches "_start", at which point
|
||
the dld will have had a chance to initialize the child. */
|
||
#if defined(SOLIB_RESTART)
|
||
SOLIB_RESTART ();
|
||
#endif
|
||
#ifdef SOLIB_CREATE_INFERIOR_HOOK
|
||
SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
|
||
#endif
|
||
|
||
/* Reinsert all breakpoints. (Those which were symbolic have
|
||
been reset to the proper address in the new a.out, thanks
|
||
to symbol_file_command...) */
|
||
insert_breakpoints ();
|
||
|
||
/* The next resume of this inferior should bring it to the shlib
|
||
startup breakpoints. (If the user had also set bp's on
|
||
"main" from the old (parent) process, then they'll auto-
|
||
matically get reset there in the new process.) */
|
||
}
|
||
|
||
/* Non-zero if we just simulating a single-step. This is needed
|
||
because we cannot remove the breakpoints in the inferior process
|
||
until after the `wait' in `wait_for_inferior'. */
|
||
static int singlestep_breakpoints_inserted_p = 0;
|
||
|
||
/* The thread we inserted single-step breakpoints for. */
|
||
static ptid_t singlestep_ptid;
|
||
|
||
/* If another thread hit the singlestep breakpoint, we save the original
|
||
thread here so that we can resume single-stepping it later. */
|
||
static ptid_t saved_singlestep_ptid;
|
||
static int stepping_past_singlestep_breakpoint;
|
||
|
||
|
||
/* Things to clean up if we QUIT out of resume (). */
|
||
static void
|
||
resume_cleanups (void *ignore)
|
||
{
|
||
normal_stop ();
|
||
}
|
||
|
||
static const char schedlock_off[] = "off";
|
||
static const char schedlock_on[] = "on";
|
||
static const char schedlock_step[] = "step";
|
||
static const char *scheduler_mode = schedlock_off;
|
||
static const char *scheduler_enums[] = {
|
||
schedlock_off,
|
||
schedlock_on,
|
||
schedlock_step,
|
||
NULL
|
||
};
|
||
|
||
static void
|
||
set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
|
||
{
|
||
/* NOTE: cagney/2002-03-17: The add_show_from_set() function clones
|
||
the set command passed as a parameter. The clone operation will
|
||
include (BUG?) any ``set'' command callback, if present.
|
||
Commands like ``info set'' call all the ``show'' command
|
||
callbacks. Unfortunately, for ``show'' commands cloned from
|
||
``set'', this includes callbacks belonging to ``set'' commands.
|
||
Making this worse, this only occures if add_show_from_set() is
|
||
called after add_cmd_sfunc() (BUG?). */
|
||
if (cmd_type (c) == set_cmd)
|
||
if (!target_can_lock_scheduler)
|
||
{
|
||
scheduler_mode = schedlock_off;
|
||
error ("Target '%s' cannot support this command.", target_shortname);
|
||
}
|
||
}
|
||
|
||
|
||
/* Resume the inferior, but allow a QUIT. This is useful if the user
|
||
wants to interrupt some lengthy single-stepping operation
|
||
(for child processes, the SIGINT goes to the inferior, and so
|
||
we get a SIGINT random_signal, but for remote debugging and perhaps
|
||
other targets, that's not true).
|
||
|
||
STEP nonzero if we should step (zero to continue instead).
|
||
SIG is the signal to give the inferior (zero for none). */
|
||
void
|
||
resume (int step, enum target_signal sig)
|
||
{
|
||
int should_resume = 1;
|
||
struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
|
||
QUIT;
|
||
|
||
/* FIXME: calling breakpoint_here_p (read_pc ()) three times! */
|
||
|
||
|
||
/* Some targets (e.g. Solaris x86) have a kernel bug when stepping
|
||
over an instruction that causes a page fault without triggering
|
||
a hardware watchpoint. The kernel properly notices that it shouldn't
|
||
stop, because the hardware watchpoint is not triggered, but it forgets
|
||
the step request and continues the program normally.
|
||
Work around the problem by removing hardware watchpoints if a step is
|
||
requested, GDB will check for a hardware watchpoint trigger after the
|
||
step anyway. */
|
||
if (CANNOT_STEP_HW_WATCHPOINTS && step && breakpoints_inserted)
|
||
remove_hw_watchpoints ();
|
||
|
||
|
||
/* Normally, by the time we reach `resume', the breakpoints are either
|
||
removed or inserted, as appropriate. The exception is if we're sitting
|
||
at a permanent breakpoint; we need to step over it, but permanent
|
||
breakpoints can't be removed. So we have to test for it here. */
|
||
if (breakpoint_here_p (read_pc ()) == permanent_breakpoint_here)
|
||
SKIP_PERMANENT_BREAKPOINT ();
|
||
|
||
if (SOFTWARE_SINGLE_STEP_P () && step)
|
||
{
|
||
/* Do it the hard way, w/temp breakpoints */
|
||
SOFTWARE_SINGLE_STEP (sig, 1 /*insert-breakpoints */ );
|
||
/* ...and don't ask hardware to do it. */
|
||
step = 0;
|
||
/* and do not pull these breakpoints until after a `wait' in
|
||
`wait_for_inferior' */
|
||
singlestep_breakpoints_inserted_p = 1;
|
||
singlestep_ptid = inferior_ptid;
|
||
}
|
||
|
||
/* Handle any optimized stores to the inferior NOW... */
|
||
#ifdef DO_DEFERRED_STORES
|
||
DO_DEFERRED_STORES;
|
||
#endif
|
||
|
||
/* If there were any forks/vforks/execs that were caught and are
|
||
now to be followed, then do so. */
|
||
switch (pending_follow.kind)
|
||
{
|
||
case TARGET_WAITKIND_FORKED:
|
||
case TARGET_WAITKIND_VFORKED:
|
||
pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
|
||
if (follow_fork ())
|
||
should_resume = 0;
|
||
break;
|
||
|
||
case TARGET_WAITKIND_EXECD:
|
||
/* follow_exec is called as soon as the exec event is seen. */
|
||
pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
|
||
break;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
|
||
/* Install inferior's terminal modes. */
|
||
target_terminal_inferior ();
|
||
|
||
if (should_resume)
|
||
{
|
||
ptid_t resume_ptid;
|
||
|
||
resume_ptid = RESUME_ALL; /* Default */
|
||
|
||
if ((step || singlestep_breakpoints_inserted_p) &&
|
||
(stepping_past_singlestep_breakpoint
|
||
|| (!breakpoints_inserted && breakpoint_here_p (read_pc ()))))
|
||
{
|
||
/* Stepping past a breakpoint without inserting breakpoints.
|
||
Make sure only the current thread gets to step, so that
|
||
other threads don't sneak past breakpoints while they are
|
||
not inserted. */
|
||
|
||
resume_ptid = inferior_ptid;
|
||
}
|
||
|
||
if ((scheduler_mode == schedlock_on) ||
|
||
(scheduler_mode == schedlock_step &&
|
||
(step || singlestep_breakpoints_inserted_p)))
|
||
{
|
||
/* User-settable 'scheduler' mode requires solo thread resume. */
|
||
resume_ptid = inferior_ptid;
|
||
}
|
||
|
||
if (CANNOT_STEP_BREAKPOINT)
|
||
{
|
||
/* Most targets can step a breakpoint instruction, thus
|
||
executing it normally. But if this one cannot, just
|
||
continue and we will hit it anyway. */
|
||
if (step && breakpoints_inserted && breakpoint_here_p (read_pc ()))
|
||
step = 0;
|
||
}
|
||
target_resume (resume_ptid, step, sig);
|
||
}
|
||
|
||
discard_cleanups (old_cleanups);
|
||
}
|
||
|
||
|
||
/* Clear out all variables saying what to do when inferior is continued.
|
||
First do this, then set the ones you want, then call `proceed'. */
|
||
|
||
void
|
||
clear_proceed_status (void)
|
||
{
|
||
trap_expected = 0;
|
||
step_range_start = 0;
|
||
step_range_end = 0;
|
||
step_frame_id = null_frame_id;
|
||
step_over_calls = STEP_OVER_UNDEBUGGABLE;
|
||
stop_after_trap = 0;
|
||
stop_soon = NO_STOP_QUIETLY;
|
||
proceed_to_finish = 0;
|
||
breakpoint_proceeded = 1; /* We're about to proceed... */
|
||
|
||
/* Discard any remaining commands or status from previous stop. */
|
||
bpstat_clear (&stop_bpstat);
|
||
}
|
||
|
||
/* This should be suitable for any targets that support threads. */
|
||
|
||
static int
|
||
prepare_to_proceed (void)
|
||
{
|
||
ptid_t wait_ptid;
|
||
struct target_waitstatus wait_status;
|
||
|
||
/* Get the last target status returned by target_wait(). */
|
||
get_last_target_status (&wait_ptid, &wait_status);
|
||
|
||
/* Make sure we were stopped either at a breakpoint, or because
|
||
of a Ctrl-C. */
|
||
if (wait_status.kind != TARGET_WAITKIND_STOPPED
|
||
|| (wait_status.value.sig != TARGET_SIGNAL_TRAP &&
|
||
wait_status.value.sig != TARGET_SIGNAL_INT))
|
||
{
|
||
return 0;
|
||
}
|
||
|
||
if (!ptid_equal (wait_ptid, minus_one_ptid)
|
||
&& !ptid_equal (inferior_ptid, wait_ptid))
|
||
{
|
||
/* Switched over from WAIT_PID. */
|
||
CORE_ADDR wait_pc = read_pc_pid (wait_ptid);
|
||
|
||
if (wait_pc != read_pc ())
|
||
{
|
||
/* Switch back to WAIT_PID thread. */
|
||
inferior_ptid = wait_ptid;
|
||
|
||
/* FIXME: This stuff came from switch_to_thread() in
|
||
thread.c (which should probably be a public function). */
|
||
flush_cached_frames ();
|
||
registers_changed ();
|
||
stop_pc = wait_pc;
|
||
select_frame (get_current_frame ());
|
||
}
|
||
|
||
/* We return 1 to indicate that there is a breakpoint here,
|
||
so we need to step over it before continuing to avoid
|
||
hitting it straight away. */
|
||
if (breakpoint_here_p (wait_pc))
|
||
return 1;
|
||
}
|
||
|
||
return 0;
|
||
|
||
}
|
||
|
||
/* Record the pc of the program the last time it stopped. This is
|
||
just used internally by wait_for_inferior, but need to be preserved
|
||
over calls to it and cleared when the inferior is started. */
|
||
static CORE_ADDR prev_pc;
|
||
|
||
/* Basic routine for continuing the program in various fashions.
|
||
|
||
ADDR is the address to resume at, or -1 for resume where stopped.
|
||
SIGGNAL is the signal to give it, or 0 for none,
|
||
or -1 for act according to how it stopped.
|
||
STEP is nonzero if should trap after one instruction.
|
||
-1 means return after that and print nothing.
|
||
You should probably set various step_... variables
|
||
before calling here, if you are stepping.
|
||
|
||
You should call clear_proceed_status before calling proceed. */
|
||
|
||
void
|
||
proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
|
||
{
|
||
int oneproc = 0;
|
||
|
||
if (step > 0)
|
||
step_start_function = find_pc_function (read_pc ());
|
||
if (step < 0)
|
||
stop_after_trap = 1;
|
||
|
||
if (addr == (CORE_ADDR) -1)
|
||
{
|
||
/* If there is a breakpoint at the address we will resume at,
|
||
step one instruction before inserting breakpoints
|
||
so that we do not stop right away (and report a second
|
||
hit at this breakpoint). */
|
||
|
||
if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
|
||
oneproc = 1;
|
||
|
||
#ifndef STEP_SKIPS_DELAY
|
||
#define STEP_SKIPS_DELAY(pc) (0)
|
||
#define STEP_SKIPS_DELAY_P (0)
|
||
#endif
|
||
/* Check breakpoint_here_p first, because breakpoint_here_p is fast
|
||
(it just checks internal GDB data structures) and STEP_SKIPS_DELAY
|
||
is slow (it needs to read memory from the target). */
|
||
if (STEP_SKIPS_DELAY_P
|
||
&& breakpoint_here_p (read_pc () + 4)
|
||
&& STEP_SKIPS_DELAY (read_pc ()))
|
||
oneproc = 1;
|
||
}
|
||
else
|
||
{
|
||
write_pc (addr);
|
||
}
|
||
|
||
/* In a multi-threaded task we may select another thread
|
||
and then continue or step.
|
||
|
||
But if the old thread was stopped at a breakpoint, it
|
||
will immediately cause another breakpoint stop without
|
||
any execution (i.e. it will report a breakpoint hit
|
||
incorrectly). So we must step over it first.
|
||
|
||
prepare_to_proceed checks the current thread against the thread
|
||
that reported the most recent event. If a step-over is required
|
||
it returns TRUE and sets the current thread to the old thread. */
|
||
if (prepare_to_proceed () && breakpoint_here_p (read_pc ()))
|
||
oneproc = 1;
|
||
|
||
#ifdef HP_OS_BUG
|
||
if (trap_expected_after_continue)
|
||
{
|
||
/* If (step == 0), a trap will be automatically generated after
|
||
the first instruction is executed. Force step one
|
||
instruction to clear this condition. This should not occur
|
||
if step is nonzero, but it is harmless in that case. */
|
||
oneproc = 1;
|
||
trap_expected_after_continue = 0;
|
||
}
|
||
#endif /* HP_OS_BUG */
|
||
|
||
if (oneproc)
|
||
/* We will get a trace trap after one instruction.
|
||
Continue it automatically and insert breakpoints then. */
|
||
trap_expected = 1;
|
||
else
|
||
{
|
||
insert_breakpoints ();
|
||
/* If we get here there was no call to error() in
|
||
insert breakpoints -- so they were inserted. */
|
||
breakpoints_inserted = 1;
|
||
}
|
||
|
||
if (siggnal != TARGET_SIGNAL_DEFAULT)
|
||
stop_signal = siggnal;
|
||
/* If this signal should not be seen by program,
|
||
give it zero. Used for debugging signals. */
|
||
else if (!signal_program[stop_signal])
|
||
stop_signal = TARGET_SIGNAL_0;
|
||
|
||
annotate_starting ();
|
||
|
||
/* Make sure that output from GDB appears before output from the
|
||
inferior. */
|
||
gdb_flush (gdb_stdout);
|
||
|
||
/* Refresh prev_pc value just prior to resuming. This used to be
|
||
done in stop_stepping, however, setting prev_pc there did not handle
|
||
scenarios such as inferior function calls or returning from
|
||
a function via the return command. In those cases, the prev_pc
|
||
value was not set properly for subsequent commands. The prev_pc value
|
||
is used to initialize the starting line number in the ecs. With an
|
||
invalid value, the gdb next command ends up stopping at the position
|
||
represented by the next line table entry past our start position.
|
||
On platforms that generate one line table entry per line, this
|
||
is not a problem. However, on the ia64, the compiler generates
|
||
extraneous line table entries that do not increase the line number.
|
||
When we issue the gdb next command on the ia64 after an inferior call
|
||
or a return command, we often end up a few instructions forward, still
|
||
within the original line we started.
|
||
|
||
An attempt was made to have init_execution_control_state () refresh
|
||
the prev_pc value before calculating the line number. This approach
|
||
did not work because on platforms that use ptrace, the pc register
|
||
cannot be read unless the inferior is stopped. At that point, we
|
||
are not guaranteed the inferior is stopped and so the read_pc ()
|
||
call can fail. Setting the prev_pc value here ensures the value is
|
||
updated correctly when the inferior is stopped. */
|
||
prev_pc = read_pc ();
|
||
|
||
/* Resume inferior. */
|
||
resume (oneproc || step || bpstat_should_step (), stop_signal);
|
||
|
||
/* Wait for it to stop (if not standalone)
|
||
and in any case decode why it stopped, and act accordingly. */
|
||
/* Do this only if we are not using the event loop, or if the target
|
||
does not support asynchronous execution. */
|
||
if (!event_loop_p || !target_can_async_p ())
|
||
{
|
||
wait_for_inferior ();
|
||
normal_stop ();
|
||
}
|
||
}
|
||
|
||
|
||
/* Start remote-debugging of a machine over a serial link. */
|
||
|
||
void
|
||
start_remote (void)
|
||
{
|
||
init_thread_list ();
|
||
init_wait_for_inferior ();
|
||
stop_soon = STOP_QUIETLY;
|
||
trap_expected = 0;
|
||
|
||
/* Always go on waiting for the target, regardless of the mode. */
|
||
/* FIXME: cagney/1999-09-23: At present it isn't possible to
|
||
indicate to wait_for_inferior that a target should timeout if
|
||
nothing is returned (instead of just blocking). Because of this,
|
||
targets expecting an immediate response need to, internally, set
|
||
things up so that the target_wait() is forced to eventually
|
||
timeout. */
|
||
/* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
|
||
differentiate to its caller what the state of the target is after
|
||
the initial open has been performed. Here we're assuming that
|
||
the target has stopped. It should be possible to eventually have
|
||
target_open() return to the caller an indication that the target
|
||
is currently running and GDB state should be set to the same as
|
||
for an async run. */
|
||
wait_for_inferior ();
|
||
normal_stop ();
|
||
}
|
||
|
||
/* Initialize static vars when a new inferior begins. */
|
||
|
||
void
|
||
init_wait_for_inferior (void)
|
||
{
|
||
/* These are meaningless until the first time through wait_for_inferior. */
|
||
prev_pc = 0;
|
||
|
||
#ifdef HP_OS_BUG
|
||
trap_expected_after_continue = 0;
|
||
#endif
|
||
breakpoints_inserted = 0;
|
||
breakpoint_init_inferior (inf_starting);
|
||
|
||
/* Don't confuse first call to proceed(). */
|
||
stop_signal = TARGET_SIGNAL_0;
|
||
|
||
/* The first resume is not following a fork/vfork/exec. */
|
||
pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
|
||
|
||
/* See wait_for_inferior's handling of SYSCALL_ENTRY/RETURN events. */
|
||
number_of_threads_in_syscalls = 0;
|
||
|
||
clear_proceed_status ();
|
||
|
||
stepping_past_singlestep_breakpoint = 0;
|
||
}
|
||
|
||
static void
|
||
delete_breakpoint_current_contents (void *arg)
|
||
{
|
||
struct breakpoint **breakpointp = (struct breakpoint **) arg;
|
||
if (*breakpointp != NULL)
|
||
{
|
||
delete_breakpoint (*breakpointp);
|
||
*breakpointp = NULL;
|
||
}
|
||
}
|
||
|
||
/* This enum encodes possible reasons for doing a target_wait, so that
|
||
wfi can call target_wait in one place. (Ultimately the call will be
|
||
moved out of the infinite loop entirely.) */
|
||
|
||
enum infwait_states
|
||
{
|
||
infwait_normal_state,
|
||
infwait_thread_hop_state,
|
||
infwait_nullified_state,
|
||
infwait_nonstep_watch_state
|
||
};
|
||
|
||
/* Why did the inferior stop? Used to print the appropriate messages
|
||
to the interface from within handle_inferior_event(). */
|
||
enum inferior_stop_reason
|
||
{
|
||
/* We don't know why. */
|
||
STOP_UNKNOWN,
|
||
/* Step, next, nexti, stepi finished. */
|
||
END_STEPPING_RANGE,
|
||
/* Found breakpoint. */
|
||
BREAKPOINT_HIT,
|
||
/* Inferior terminated by signal. */
|
||
SIGNAL_EXITED,
|
||
/* Inferior exited. */
|
||
EXITED,
|
||
/* Inferior received signal, and user asked to be notified. */
|
||
SIGNAL_RECEIVED
|
||
};
|
||
|
||
/* This structure contains what used to be local variables in
|
||
wait_for_inferior. Probably many of them can return to being
|
||
locals in handle_inferior_event. */
|
||
|
||
struct execution_control_state
|
||
{
|
||
struct target_waitstatus ws;
|
||
struct target_waitstatus *wp;
|
||
int another_trap;
|
||
int random_signal;
|
||
CORE_ADDR stop_func_start;
|
||
CORE_ADDR stop_func_end;
|
||
char *stop_func_name;
|
||
struct symtab_and_line sal;
|
||
int remove_breakpoints_on_following_step;
|
||
int current_line;
|
||
struct symtab *current_symtab;
|
||
int handling_longjmp; /* FIXME */
|
||
ptid_t ptid;
|
||
ptid_t saved_inferior_ptid;
|
||
int update_step_sp;
|
||
int stepping_through_solib_after_catch;
|
||
bpstat stepping_through_solib_catchpoints;
|
||
int enable_hw_watchpoints_after_wait;
|
||
int stepping_through_sigtramp;
|
||
int new_thread_event;
|
||
struct target_waitstatus tmpstatus;
|
||
enum infwait_states infwait_state;
|
||
ptid_t waiton_ptid;
|
||
int wait_some_more;
|
||
};
|
||
|
||
void init_execution_control_state (struct execution_control_state *ecs);
|
||
|
||
static void handle_step_into_function (struct execution_control_state *ecs);
|
||
void handle_inferior_event (struct execution_control_state *ecs);
|
||
|
||
static void check_sigtramp2 (struct execution_control_state *ecs);
|
||
static void step_into_function (struct execution_control_state *ecs);
|
||
static void step_over_function (struct execution_control_state *ecs);
|
||
static void stop_stepping (struct execution_control_state *ecs);
|
||
static void prepare_to_wait (struct execution_control_state *ecs);
|
||
static void keep_going (struct execution_control_state *ecs);
|
||
static void print_stop_reason (enum inferior_stop_reason stop_reason,
|
||
int stop_info);
|
||
|
||
/* Wait for control to return from inferior to debugger.
|
||
If inferior gets a signal, we may decide to start it up again
|
||
instead of returning. That is why there is a loop in this function.
|
||
When this function actually returns it means the inferior
|
||
should be left stopped and GDB should read more commands. */
|
||
|
||
void
|
||
wait_for_inferior (void)
|
||
{
|
||
struct cleanup *old_cleanups;
|
||
struct execution_control_state ecss;
|
||
struct execution_control_state *ecs;
|
||
|
||
old_cleanups = make_cleanup (delete_step_resume_breakpoint,
|
||
&step_resume_breakpoint);
|
||
make_cleanup (delete_breakpoint_current_contents,
|
||
&through_sigtramp_breakpoint);
|
||
|
||
/* wfi still stays in a loop, so it's OK just to take the address of
|
||
a local to get the ecs pointer. */
|
||
ecs = &ecss;
|
||
|
||
/* Fill in with reasonable starting values. */
|
||
init_execution_control_state (ecs);
|
||
|
||
/* We'll update this if & when we switch to a new thread. */
|
||
previous_inferior_ptid = inferior_ptid;
|
||
|
||
overlay_cache_invalid = 1;
|
||
|
||
/* We have to invalidate the registers BEFORE calling target_wait
|
||
because they can be loaded from the target while in target_wait.
|
||
This makes remote debugging a bit more efficient for those
|
||
targets that provide critical registers as part of their normal
|
||
status mechanism. */
|
||
|
||
registers_changed ();
|
||
|
||
while (1)
|
||
{
|
||
if (target_wait_hook)
|
||
ecs->ptid = target_wait_hook (ecs->waiton_ptid, ecs->wp);
|
||
else
|
||
ecs->ptid = target_wait (ecs->waiton_ptid, ecs->wp);
|
||
|
||
/* Now figure out what to do with the result of the result. */
|
||
handle_inferior_event (ecs);
|
||
|
||
if (!ecs->wait_some_more)
|
||
break;
|
||
}
|
||
do_cleanups (old_cleanups);
|
||
}
|
||
|
||
/* Asynchronous version of wait_for_inferior. It is called by the
|
||
event loop whenever a change of state is detected on the file
|
||
descriptor corresponding to the target. It can be called more than
|
||
once to complete a single execution command. In such cases we need
|
||
to keep the state in a global variable ASYNC_ECSS. If it is the
|
||
last time that this function is called for a single execution
|
||
command, then report to the user that the inferior has stopped, and
|
||
do the necessary cleanups. */
|
||
|
||
struct execution_control_state async_ecss;
|
||
struct execution_control_state *async_ecs;
|
||
|
||
void
|
||
fetch_inferior_event (void *client_data)
|
||
{
|
||
static struct cleanup *old_cleanups;
|
||
|
||
async_ecs = &async_ecss;
|
||
|
||
if (!async_ecs->wait_some_more)
|
||
{
|
||
old_cleanups = make_exec_cleanup (delete_step_resume_breakpoint,
|
||
&step_resume_breakpoint);
|
||
make_exec_cleanup (delete_breakpoint_current_contents,
|
||
&through_sigtramp_breakpoint);
|
||
|
||
/* Fill in with reasonable starting values. */
|
||
init_execution_control_state (async_ecs);
|
||
|
||
/* We'll update this if & when we switch to a new thread. */
|
||
previous_inferior_ptid = inferior_ptid;
|
||
|
||
overlay_cache_invalid = 1;
|
||
|
||
/* We have to invalidate the registers BEFORE calling target_wait
|
||
because they can be loaded from the target while in target_wait.
|
||
This makes remote debugging a bit more efficient for those
|
||
targets that provide critical registers as part of their normal
|
||
status mechanism. */
|
||
|
||
registers_changed ();
|
||
}
|
||
|
||
if (target_wait_hook)
|
||
async_ecs->ptid =
|
||
target_wait_hook (async_ecs->waiton_ptid, async_ecs->wp);
|
||
else
|
||
async_ecs->ptid = target_wait (async_ecs->waiton_ptid, async_ecs->wp);
|
||
|
||
/* Now figure out what to do with the result of the result. */
|
||
handle_inferior_event (async_ecs);
|
||
|
||
if (!async_ecs->wait_some_more)
|
||
{
|
||
/* Do only the cleanups that have been added by this
|
||
function. Let the continuations for the commands do the rest,
|
||
if there are any. */
|
||
do_exec_cleanups (old_cleanups);
|
||
normal_stop ();
|
||
if (step_multi && stop_step)
|
||
inferior_event_handler (INF_EXEC_CONTINUE, NULL);
|
||
else
|
||
inferior_event_handler (INF_EXEC_COMPLETE, NULL);
|
||
}
|
||
}
|
||
|
||
/* Prepare an execution control state for looping through a
|
||
wait_for_inferior-type loop. */
|
||
|
||
void
|
||
init_execution_control_state (struct execution_control_state *ecs)
|
||
{
|
||
/* ecs->another_trap? */
|
||
ecs->random_signal = 0;
|
||
ecs->remove_breakpoints_on_following_step = 0;
|
||
ecs->handling_longjmp = 0; /* FIXME */
|
||
ecs->update_step_sp = 0;
|
||
ecs->stepping_through_solib_after_catch = 0;
|
||
ecs->stepping_through_solib_catchpoints = NULL;
|
||
ecs->enable_hw_watchpoints_after_wait = 0;
|
||
ecs->stepping_through_sigtramp = 0;
|
||
ecs->sal = find_pc_line (prev_pc, 0);
|
||
ecs->current_line = ecs->sal.line;
|
||
ecs->current_symtab = ecs->sal.symtab;
|
||
ecs->infwait_state = infwait_normal_state;
|
||
ecs->waiton_ptid = pid_to_ptid (-1);
|
||
ecs->wp = &(ecs->ws);
|
||
}
|
||
|
||
/* Call this function before setting step_resume_breakpoint, as a
|
||
sanity check. There should never be more than one step-resume
|
||
breakpoint per thread, so we should never be setting a new
|
||
step_resume_breakpoint when one is already active. */
|
||
static void
|
||
check_for_old_step_resume_breakpoint (void)
|
||
{
|
||
if (step_resume_breakpoint)
|
||
warning
|
||
("GDB bug: infrun.c (wait_for_inferior): dropping old step_resume breakpoint");
|
||
}
|
||
|
||
/* Return the cached copy of the last pid/waitstatus returned by
|
||
target_wait()/target_wait_hook(). The data is actually cached by
|
||
handle_inferior_event(), which gets called immediately after
|
||
target_wait()/target_wait_hook(). */
|
||
|
||
void
|
||
get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
|
||
{
|
||
*ptidp = target_last_wait_ptid;
|
||
*status = target_last_waitstatus;
|
||
}
|
||
|
||
/* Switch thread contexts, maintaining "infrun state". */
|
||
|
||
static void
|
||
context_switch (struct execution_control_state *ecs)
|
||
{
|
||
/* Caution: it may happen that the new thread (or the old one!)
|
||
is not in the thread list. In this case we must not attempt
|
||
to "switch context", or we run the risk that our context may
|
||
be lost. This may happen as a result of the target module
|
||
mishandling thread creation. */
|
||
|
||
if (in_thread_list (inferior_ptid) && in_thread_list (ecs->ptid))
|
||
{ /* Perform infrun state context switch: */
|
||
/* Save infrun state for the old thread. */
|
||
save_infrun_state (inferior_ptid, prev_pc,
|
||
trap_expected, step_resume_breakpoint,
|
||
through_sigtramp_breakpoint, step_range_start,
|
||
step_range_end, &step_frame_id,
|
||
ecs->handling_longjmp, ecs->another_trap,
|
||
ecs->stepping_through_solib_after_catch,
|
||
ecs->stepping_through_solib_catchpoints,
|
||
ecs->stepping_through_sigtramp,
|
||
ecs->current_line, ecs->current_symtab, step_sp);
|
||
|
||
/* Load infrun state for the new thread. */
|
||
load_infrun_state (ecs->ptid, &prev_pc,
|
||
&trap_expected, &step_resume_breakpoint,
|
||
&through_sigtramp_breakpoint, &step_range_start,
|
||
&step_range_end, &step_frame_id,
|
||
&ecs->handling_longjmp, &ecs->another_trap,
|
||
&ecs->stepping_through_solib_after_catch,
|
||
&ecs->stepping_through_solib_catchpoints,
|
||
&ecs->stepping_through_sigtramp,
|
||
&ecs->current_line, &ecs->current_symtab, &step_sp);
|
||
}
|
||
inferior_ptid = ecs->ptid;
|
||
}
|
||
|
||
/* Wrapper for PC_IN_SIGTRAMP that takes care of the need to find the
|
||
function's name.
|
||
|
||
In a classic example of "left hand VS right hand", "infrun.c" was
|
||
trying to improve GDB's performance by caching the result of calls
|
||
to calls to find_pc_partial_funtion, while at the same time
|
||
find_pc_partial_function was also trying to ramp up performance by
|
||
caching its most recent return value. The below makes the the
|
||
function find_pc_partial_function solely responsibile for
|
||
performance issues (the local cache that relied on a global
|
||
variable - arrrggg - deleted).
|
||
|
||
Using the testsuite and gcov, it was found that dropping the local
|
||
"infrun.c" cache and instead relying on find_pc_partial_function
|
||
increased the number of calls to 12000 (from 10000), but the number
|
||
of times find_pc_partial_function's cache missed (this is what
|
||
matters) was only increased by only 4 (to 3569). (A quick back of
|
||
envelope caculation suggests that the extra 2000 function calls
|
||
@1000 extra instructions per call make the 1 MIP VAX testsuite run
|
||
take two extra seconds, oops :-)
|
||
|
||
Long term, this function can be eliminated, replaced by the code:
|
||
get_frame_type(current_frame()) == SIGTRAMP_FRAME (for new
|
||
architectures this is very cheap). */
|
||
|
||
static int
|
||
pc_in_sigtramp (CORE_ADDR pc)
|
||
{
|
||
char *name;
|
||
find_pc_partial_function (pc, &name, NULL, NULL);
|
||
return PC_IN_SIGTRAMP (pc, name);
|
||
}
|
||
|
||
/* Handle the inferior event in the cases when we just stepped
|
||
into a function. */
|
||
|
||
static void
|
||
handle_step_into_function (struct execution_control_state *ecs)
|
||
{
|
||
CORE_ADDR real_stop_pc;
|
||
|
||
if ((step_over_calls == STEP_OVER_NONE)
|
||
|| ((step_range_end == 1)
|
||
&& in_prologue (prev_pc, ecs->stop_func_start)))
|
||
{
|
||
/* I presume that step_over_calls is only 0 when we're
|
||
supposed to be stepping at the assembly language level
|
||
("stepi"). Just stop. */
|
||
/* Also, maybe we just did a "nexti" inside a prolog,
|
||
so we thought it was a subroutine call but it was not.
|
||
Stop as well. FENN */
|
||
stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
if (step_over_calls == STEP_OVER_ALL || IGNORE_HELPER_CALL (stop_pc))
|
||
{
|
||
/* We're doing a "next". */
|
||
|
||
if (pc_in_sigtramp (stop_pc)
|
||
&& frame_id_inner (step_frame_id,
|
||
frame_id_build (read_sp (), 0)))
|
||
/* We stepped out of a signal handler, and into its
|
||
calling trampoline. This is misdetected as a
|
||
subroutine call, but stepping over the signal
|
||
trampoline isn't such a bad idea. In order to do that,
|
||
we have to ignore the value in step_frame_id, since
|
||
that doesn't represent the frame that'll reach when we
|
||
return from the signal trampoline. Otherwise we'll
|
||
probably continue to the end of the program. */
|
||
step_frame_id = null_frame_id;
|
||
|
||
step_over_function (ecs);
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* If we are in a function call trampoline (a stub between
|
||
the calling routine and the real function), locate the real
|
||
function. That's what tells us (a) whether we want to step
|
||
into it at all, and (b) what prologue we want to run to
|
||
the end of, if we do step into it. */
|
||
real_stop_pc = skip_language_trampoline (stop_pc);
|
||
if (real_stop_pc == 0)
|
||
real_stop_pc = SKIP_TRAMPOLINE_CODE (stop_pc);
|
||
if (real_stop_pc != 0)
|
||
ecs->stop_func_start = real_stop_pc;
|
||
|
||
/* If we have line number information for the function we
|
||
are thinking of stepping into, step into it.
|
||
|
||
If there are several symtabs at that PC (e.g. with include
|
||
files), just want to know whether *any* of them have line
|
||
numbers. find_pc_line handles this. */
|
||
{
|
||
struct symtab_and_line tmp_sal;
|
||
|
||
tmp_sal = find_pc_line (ecs->stop_func_start, 0);
|
||
if (tmp_sal.line != 0)
|
||
{
|
||
step_into_function (ecs);
|
||
return;
|
||
}
|
||
}
|
||
|
||
/* If we have no line number and the step-stop-if-no-debug
|
||
is set, we stop the step so that the user has a chance to
|
||
switch in assembly mode. */
|
||
if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug)
|
||
{
|
||
stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
step_over_function (ecs);
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
static void
|
||
adjust_pc_after_break (struct execution_control_state *ecs)
|
||
{
|
||
CORE_ADDR stop_pc;
|
||
|
||
/* If this target does not decrement the PC after breakpoints, then
|
||
we have nothing to do. */
|
||
if (DECR_PC_AFTER_BREAK == 0)
|
||
return;
|
||
|
||
/* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
|
||
we aren't, just return.
|
||
|
||
We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
|
||
affected by DECR_PC_AFTER_BREAK. Other waitkinds which are implemented
|
||
by software breakpoints should be handled through the normal breakpoint
|
||
layer.
|
||
|
||
NOTE drow/2004-01-31: On some targets, breakpoints may generate
|
||
different signals (SIGILL or SIGEMT for instance), but it is less
|
||
clear where the PC is pointing afterwards. It may not match
|
||
DECR_PC_AFTER_BREAK. I don't know any specific target that generates
|
||
these signals at breakpoints (the code has been in GDB since at least
|
||
1992) so I can not guess how to handle them here.
|
||
|
||
In earlier versions of GDB, a target with HAVE_NONSTEPPABLE_WATCHPOINTS
|
||
would have the PC after hitting a watchpoint affected by
|
||
DECR_PC_AFTER_BREAK. I haven't found any target with both of these set
|
||
in GDB history, and it seems unlikely to be correct, so
|
||
HAVE_NONSTEPPABLE_WATCHPOINTS is not checked here. */
|
||
|
||
if (ecs->ws.kind != TARGET_WAITKIND_STOPPED)
|
||
return;
|
||
|
||
if (ecs->ws.value.sig != TARGET_SIGNAL_TRAP)
|
||
return;
|
||
|
||
/* Find the location where (if we've hit a breakpoint) the breakpoint would
|
||
be. */
|
||
stop_pc = read_pc_pid (ecs->ptid) - DECR_PC_AFTER_BREAK;
|
||
|
||
/* If we're software-single-stepping, then assume this is a breakpoint.
|
||
NOTE drow/2004-01-17: This doesn't check that the PC matches, or that
|
||
we're even in the right thread. The software-single-step code needs
|
||
some modernization.
|
||
|
||
If we're not software-single-stepping, then we first check that there
|
||
is an enabled software breakpoint at this address. If there is, and
|
||
we weren't using hardware-single-step, then we've hit the breakpoint.
|
||
|
||
If we were using hardware-single-step, we check prev_pc; if we just
|
||
stepped over an inserted software breakpoint, then we should decrement
|
||
the PC and eventually report hitting the breakpoint. The prev_pc check
|
||
prevents us from decrementing the PC if we just stepped over a jump
|
||
instruction and landed on the instruction after a breakpoint.
|
||
|
||
The last bit checks that we didn't hit a breakpoint in a signal handler
|
||
without an intervening stop in sigtramp, which is detected by a new
|
||
stack pointer value below any usual function calling stack adjustments.
|
||
|
||
NOTE drow/2004-01-17: I'm not sure that this is necessary. The check
|
||
predates checking for software single step at the same time. Also,
|
||
if we've moved into a signal handler we should have seen the
|
||
signal. */
|
||
|
||
if ((SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
|
||
|| (software_breakpoint_inserted_here_p (stop_pc)
|
||
&& !(currently_stepping (ecs)
|
||
&& prev_pc != stop_pc
|
||
&& !(step_range_end && INNER_THAN (read_sp (), (step_sp - 16))))))
|
||
write_pc_pid (stop_pc, ecs->ptid);
|
||
}
|
||
|
||
/* Given an execution control state that has been freshly filled in
|
||
by an event from the inferior, figure out what it means and take
|
||
appropriate action. */
|
||
|
||
void
|
||
handle_inferior_event (struct execution_control_state *ecs)
|
||
{
|
||
/* NOTE: cagney/2003-03-28: If you're looking at this code and
|
||
thinking that the variable stepped_after_stopped_by_watchpoint
|
||
isn't used, then you're wrong! The macro STOPPED_BY_WATCHPOINT,
|
||
defined in the file "config/pa/nm-hppah.h", accesses the variable
|
||
indirectly. Mutter something rude about the HP merge. */
|
||
int stepped_after_stopped_by_watchpoint;
|
||
int sw_single_step_trap_p = 0;
|
||
|
||
/* Cache the last pid/waitstatus. */
|
||
target_last_wait_ptid = ecs->ptid;
|
||
target_last_waitstatus = *ecs->wp;
|
||
|
||
adjust_pc_after_break (ecs);
|
||
|
||
switch (ecs->infwait_state)
|
||
{
|
||
case infwait_thread_hop_state:
|
||
/* Cancel the waiton_ptid. */
|
||
ecs->waiton_ptid = pid_to_ptid (-1);
|
||
/* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
|
||
is serviced in this loop, below. */
|
||
if (ecs->enable_hw_watchpoints_after_wait)
|
||
{
|
||
TARGET_ENABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
|
||
ecs->enable_hw_watchpoints_after_wait = 0;
|
||
}
|
||
stepped_after_stopped_by_watchpoint = 0;
|
||
break;
|
||
|
||
case infwait_normal_state:
|
||
/* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
|
||
is serviced in this loop, below. */
|
||
if (ecs->enable_hw_watchpoints_after_wait)
|
||
{
|
||
TARGET_ENABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
|
||
ecs->enable_hw_watchpoints_after_wait = 0;
|
||
}
|
||
stepped_after_stopped_by_watchpoint = 0;
|
||
break;
|
||
|
||
case infwait_nullified_state:
|
||
stepped_after_stopped_by_watchpoint = 0;
|
||
break;
|
||
|
||
case infwait_nonstep_watch_state:
|
||
insert_breakpoints ();
|
||
|
||
/* FIXME-maybe: is this cleaner than setting a flag? Does it
|
||
handle things like signals arriving and other things happening
|
||
in combination correctly? */
|
||
stepped_after_stopped_by_watchpoint = 1;
|
||
break;
|
||
|
||
default:
|
||
internal_error (__FILE__, __LINE__, "bad switch");
|
||
}
|
||
ecs->infwait_state = infwait_normal_state;
|
||
|
||
flush_cached_frames ();
|
||
|
||
/* If it's a new process, add it to the thread database */
|
||
|
||
ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
|
||
&& !in_thread_list (ecs->ptid));
|
||
|
||
if (ecs->ws.kind != TARGET_WAITKIND_EXITED
|
||
&& ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
|
||
{
|
||
add_thread (ecs->ptid);
|
||
|
||
ui_out_text (uiout, "[New ");
|
||
ui_out_text (uiout, target_pid_or_tid_to_str (ecs->ptid));
|
||
ui_out_text (uiout, "]\n");
|
||
|
||
#if 0
|
||
/* NOTE: This block is ONLY meant to be invoked in case of a
|
||
"thread creation event"! If it is invoked for any other
|
||
sort of event (such as a new thread landing on a breakpoint),
|
||
the event will be discarded, which is almost certainly
|
||
a bad thing!
|
||
|
||
To avoid this, the low-level module (eg. target_wait)
|
||
should call in_thread_list and add_thread, so that the
|
||
new thread is known by the time we get here. */
|
||
|
||
/* We may want to consider not doing a resume here in order
|
||
to give the user a chance to play with the new thread.
|
||
It might be good to make that a user-settable option. */
|
||
|
||
/* At this point, all threads are stopped (happens
|
||
automatically in either the OS or the native code).
|
||
Therefore we need to continue all threads in order to
|
||
make progress. */
|
||
|
||
target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
#endif
|
||
}
|
||
|
||
switch (ecs->ws.kind)
|
||
{
|
||
case TARGET_WAITKIND_LOADED:
|
||
/* Ignore gracefully during startup of the inferior, as it
|
||
might be the shell which has just loaded some objects,
|
||
otherwise add the symbols for the newly loaded objects. */
|
||
#ifdef SOLIB_ADD
|
||
if (stop_soon == NO_STOP_QUIETLY)
|
||
{
|
||
/* Remove breakpoints, SOLIB_ADD might adjust
|
||
breakpoint addresses via breakpoint_re_set. */
|
||
if (breakpoints_inserted)
|
||
remove_breakpoints ();
|
||
|
||
/* Check for any newly added shared libraries if we're
|
||
supposed to be adding them automatically. Switch
|
||
terminal for any messages produced by
|
||
breakpoint_re_set. */
|
||
target_terminal_ours_for_output ();
|
||
/* NOTE: cagney/2003-11-25: Make certain that the target
|
||
stack's section table is kept up-to-date. Architectures,
|
||
(e.g., PPC64), use the section table to perform
|
||
operations such as address => section name and hence
|
||
require the table to contain all sections (including
|
||
those found in shared libraries). */
|
||
/* NOTE: cagney/2003-11-25: Pass current_target and not
|
||
exec_ops to SOLIB_ADD. This is because current GDB is
|
||
only tooled to propagate section_table changes out from
|
||
the "current_target" (see target_resize_to_sections), and
|
||
not up from the exec stratum. This, of course, isn't
|
||
right. "infrun.c" should only interact with the
|
||
exec/process stratum, instead relying on the target stack
|
||
to propagate relevant changes (stop, section table
|
||
changed, ...) up to other layers. */
|
||
SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
|
||
target_terminal_inferior ();
|
||
|
||
/* Reinsert breakpoints and continue. */
|
||
if (breakpoints_inserted)
|
||
insert_breakpoints ();
|
||
}
|
||
#endif
|
||
resume (0, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
|
||
case TARGET_WAITKIND_SPURIOUS:
|
||
resume (0, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
|
||
case TARGET_WAITKIND_EXITED:
|
||
target_terminal_ours (); /* Must do this before mourn anyway */
|
||
print_stop_reason (EXITED, ecs->ws.value.integer);
|
||
|
||
/* Record the exit code in the convenience variable $_exitcode, so
|
||
that the user can inspect this again later. */
|
||
set_internalvar (lookup_internalvar ("_exitcode"),
|
||
value_from_longest (builtin_type_int,
|
||
(LONGEST) ecs->ws.value.integer));
|
||
gdb_flush (gdb_stdout);
|
||
target_mourn_inferior ();
|
||
singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
|
||
stop_print_frame = 0;
|
||
stop_stepping (ecs);
|
||
return;
|
||
|
||
case TARGET_WAITKIND_SIGNALLED:
|
||
stop_print_frame = 0;
|
||
stop_signal = ecs->ws.value.sig;
|
||
target_terminal_ours (); /* Must do this before mourn anyway */
|
||
|
||
/* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
|
||
reach here unless the inferior is dead. However, for years
|
||
target_kill() was called here, which hints that fatal signals aren't
|
||
really fatal on some systems. If that's true, then some changes
|
||
may be needed. */
|
||
target_mourn_inferior ();
|
||
|
||
print_stop_reason (SIGNAL_EXITED, stop_signal);
|
||
singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
|
||
stop_stepping (ecs);
|
||
return;
|
||
|
||
/* The following are the only cases in which we keep going;
|
||
the above cases end in a continue or goto. */
|
||
case TARGET_WAITKIND_FORKED:
|
||
case TARGET_WAITKIND_VFORKED:
|
||
stop_signal = TARGET_SIGNAL_TRAP;
|
||
pending_follow.kind = ecs->ws.kind;
|
||
|
||
pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
|
||
pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
|
||
|
||
stop_pc = read_pc ();
|
||
|
||
stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
|
||
|
||
ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
|
||
|
||
/* If no catchpoint triggered for this, then keep going. */
|
||
if (ecs->random_signal)
|
||
{
|
||
stop_signal = TARGET_SIGNAL_0;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
goto process_event_stop_test;
|
||
|
||
case TARGET_WAITKIND_EXECD:
|
||
stop_signal = TARGET_SIGNAL_TRAP;
|
||
|
||
/* NOTE drow/2002-12-05: This code should be pushed down into the
|
||
target_wait function. Until then following vfork on HP/UX 10.20
|
||
is probably broken by this. Of course, it's broken anyway. */
|
||
/* Is this a target which reports multiple exec events per actual
|
||
call to exec()? (HP-UX using ptrace does, for example.) If so,
|
||
ignore all but the last one. Just resume the exec'r, and wait
|
||
for the next exec event. */
|
||
if (inferior_ignoring_leading_exec_events)
|
||
{
|
||
inferior_ignoring_leading_exec_events--;
|
||
if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
|
||
ENSURE_VFORKING_PARENT_REMAINS_STOPPED (pending_follow.fork_event.
|
||
parent_pid);
|
||
target_resume (ecs->ptid, 0, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
inferior_ignoring_leading_exec_events =
|
||
target_reported_exec_events_per_exec_call () - 1;
|
||
|
||
pending_follow.execd_pathname =
|
||
savestring (ecs->ws.value.execd_pathname,
|
||
strlen (ecs->ws.value.execd_pathname));
|
||
|
||
/* This causes the eventpoints and symbol table to be reset. Must
|
||
do this now, before trying to determine whether to stop. */
|
||
follow_exec (PIDGET (inferior_ptid), pending_follow.execd_pathname);
|
||
xfree (pending_follow.execd_pathname);
|
||
|
||
stop_pc = read_pc_pid (ecs->ptid);
|
||
ecs->saved_inferior_ptid = inferior_ptid;
|
||
inferior_ptid = ecs->ptid;
|
||
|
||
stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
|
||
|
||
ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
|
||
inferior_ptid = ecs->saved_inferior_ptid;
|
||
|
||
/* If no catchpoint triggered for this, then keep going. */
|
||
if (ecs->random_signal)
|
||
{
|
||
stop_signal = TARGET_SIGNAL_0;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
goto process_event_stop_test;
|
||
|
||
/* These syscall events are returned on HP-UX, as part of its
|
||
implementation of page-protection-based "hardware" watchpoints.
|
||
HP-UX has unfortunate interactions between page-protections and
|
||
some system calls. Our solution is to disable hardware watches
|
||
when a system call is entered, and reenable them when the syscall
|
||
completes. The downside of this is that we may miss the precise
|
||
point at which a watched piece of memory is modified. "Oh well."
|
||
|
||
Note that we may have multiple threads running, which may each
|
||
enter syscalls at roughly the same time. Since we don't have a
|
||
good notion currently of whether a watched piece of memory is
|
||
thread-private, we'd best not have any page-protections active
|
||
when any thread is in a syscall. Thus, we only want to reenable
|
||
hardware watches when no threads are in a syscall.
|
||
|
||
Also, be careful not to try to gather much state about a thread
|
||
that's in a syscall. It's frequently a losing proposition. */
|
||
case TARGET_WAITKIND_SYSCALL_ENTRY:
|
||
number_of_threads_in_syscalls++;
|
||
if (number_of_threads_in_syscalls == 1)
|
||
{
|
||
TARGET_DISABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
|
||
}
|
||
resume (0, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
|
||
/* Before examining the threads further, step this thread to
|
||
get it entirely out of the syscall. (We get notice of the
|
||
event when the thread is just on the verge of exiting a
|
||
syscall. Stepping one instruction seems to get it back
|
||
into user code.)
|
||
|
||
Note that although the logical place to reenable h/w watches
|
||
is here, we cannot. We cannot reenable them before stepping
|
||
the thread (this causes the next wait on the thread to hang).
|
||
|
||
Nor can we enable them after stepping until we've done a wait.
|
||
Thus, we simply set the flag ecs->enable_hw_watchpoints_after_wait
|
||
here, which will be serviced immediately after the target
|
||
is waited on. */
|
||
case TARGET_WAITKIND_SYSCALL_RETURN:
|
||
target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
|
||
|
||
if (number_of_threads_in_syscalls > 0)
|
||
{
|
||
number_of_threads_in_syscalls--;
|
||
ecs->enable_hw_watchpoints_after_wait =
|
||
(number_of_threads_in_syscalls == 0);
|
||
}
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
|
||
case TARGET_WAITKIND_STOPPED:
|
||
stop_signal = ecs->ws.value.sig;
|
||
break;
|
||
|
||
/* We had an event in the inferior, but we are not interested
|
||
in handling it at this level. The lower layers have already
|
||
done what needs to be done, if anything.
|
||
|
||
One of the possible circumstances for this is when the
|
||
inferior produces output for the console. The inferior has
|
||
not stopped, and we are ignoring the event. Another possible
|
||
circumstance is any event which the lower level knows will be
|
||
reported multiple times without an intervening resume. */
|
||
case TARGET_WAITKIND_IGNORE:
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
|
||
/* We may want to consider not doing a resume here in order to give
|
||
the user a chance to play with the new thread. It might be good
|
||
to make that a user-settable option. */
|
||
|
||
/* At this point, all threads are stopped (happens automatically in
|
||
either the OS or the native code). Therefore we need to continue
|
||
all threads in order to make progress. */
|
||
if (ecs->new_thread_event)
|
||
{
|
||
target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
|
||
stop_pc = read_pc_pid (ecs->ptid);
|
||
|
||
if (stepping_past_singlestep_breakpoint)
|
||
{
|
||
gdb_assert (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p);
|
||
gdb_assert (ptid_equal (singlestep_ptid, ecs->ptid));
|
||
gdb_assert (!ptid_equal (singlestep_ptid, saved_singlestep_ptid));
|
||
|
||
stepping_past_singlestep_breakpoint = 0;
|
||
|
||
/* We've either finished single-stepping past the single-step
|
||
breakpoint, or stopped for some other reason. It would be nice if
|
||
we could tell, but we can't reliably. */
|
||
if (stop_signal == TARGET_SIGNAL_TRAP)
|
||
{
|
||
/* Pull the single step breakpoints out of the target. */
|
||
SOFTWARE_SINGLE_STEP (0, 0);
|
||
singlestep_breakpoints_inserted_p = 0;
|
||
|
||
ecs->random_signal = 0;
|
||
|
||
ecs->ptid = saved_singlestep_ptid;
|
||
context_switch (ecs);
|
||
if (context_hook)
|
||
context_hook (pid_to_thread_id (ecs->ptid));
|
||
|
||
resume (1, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
}
|
||
|
||
stepping_past_singlestep_breakpoint = 0;
|
||
|
||
/* See if a thread hit a thread-specific breakpoint that was meant for
|
||
another thread. If so, then step that thread past the breakpoint,
|
||
and continue it. */
|
||
|
||
if (stop_signal == TARGET_SIGNAL_TRAP)
|
||
{
|
||
int thread_hop_needed = 0;
|
||
|
||
/* Check if a regular breakpoint has been hit before checking
|
||
for a potential single step breakpoint. Otherwise, GDB will
|
||
not see this breakpoint hit when stepping onto breakpoints. */
|
||
if (breakpoints_inserted && breakpoint_here_p (stop_pc))
|
||
{
|
||
ecs->random_signal = 0;
|
||
if (!breakpoint_thread_match (stop_pc, ecs->ptid))
|
||
thread_hop_needed = 1;
|
||
}
|
||
else if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
|
||
{
|
||
ecs->random_signal = 0;
|
||
/* The call to in_thread_list is necessary because PTIDs sometimes
|
||
change when we go from single-threaded to multi-threaded. If
|
||
the singlestep_ptid is still in the list, assume that it is
|
||
really different from ecs->ptid. */
|
||
if (!ptid_equal (singlestep_ptid, ecs->ptid)
|
||
&& in_thread_list (singlestep_ptid))
|
||
{
|
||
thread_hop_needed = 1;
|
||
stepping_past_singlestep_breakpoint = 1;
|
||
saved_singlestep_ptid = singlestep_ptid;
|
||
}
|
||
}
|
||
|
||
if (thread_hop_needed)
|
||
{
|
||
int remove_status;
|
||
|
||
/* Saw a breakpoint, but it was hit by the wrong thread.
|
||
Just continue. */
|
||
|
||
if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
|
||
{
|
||
/* Pull the single step breakpoints out of the target. */
|
||
SOFTWARE_SINGLE_STEP (0, 0);
|
||
singlestep_breakpoints_inserted_p = 0;
|
||
}
|
||
|
||
remove_status = remove_breakpoints ();
|
||
/* Did we fail to remove breakpoints? If so, try
|
||
to set the PC past the bp. (There's at least
|
||
one situation in which we can fail to remove
|
||
the bp's: On HP-UX's that use ttrace, we can't
|
||
change the address space of a vforking child
|
||
process until the child exits (well, okay, not
|
||
then either :-) or execs. */
|
||
if (remove_status != 0)
|
||
{
|
||
/* FIXME! This is obviously non-portable! */
|
||
write_pc_pid (stop_pc + 4, ecs->ptid);
|
||
/* We need to restart all the threads now,
|
||
* unles we're running in scheduler-locked mode.
|
||
* Use currently_stepping to determine whether to
|
||
* step or continue.
|
||
*/
|
||
/* FIXME MVS: is there any reason not to call resume()? */
|
||
if (scheduler_mode == schedlock_on)
|
||
target_resume (ecs->ptid,
|
||
currently_stepping (ecs), TARGET_SIGNAL_0);
|
||
else
|
||
target_resume (RESUME_ALL,
|
||
currently_stepping (ecs), TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
else
|
||
{ /* Single step */
|
||
breakpoints_inserted = 0;
|
||
if (!ptid_equal (inferior_ptid, ecs->ptid))
|
||
context_switch (ecs);
|
||
ecs->waiton_ptid = ecs->ptid;
|
||
ecs->wp = &(ecs->ws);
|
||
ecs->another_trap = 1;
|
||
|
||
ecs->infwait_state = infwait_thread_hop_state;
|
||
keep_going (ecs);
|
||
registers_changed ();
|
||
return;
|
||
}
|
||
}
|
||
else if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
|
||
{
|
||
sw_single_step_trap_p = 1;
|
||
ecs->random_signal = 0;
|
||
}
|
||
}
|
||
else
|
||
ecs->random_signal = 1;
|
||
|
||
/* See if something interesting happened to the non-current thread. If
|
||
so, then switch to that thread. */
|
||
if (!ptid_equal (ecs->ptid, inferior_ptid))
|
||
{
|
||
context_switch (ecs);
|
||
|
||
if (context_hook)
|
||
context_hook (pid_to_thread_id (ecs->ptid));
|
||
|
||
flush_cached_frames ();
|
||
}
|
||
|
||
if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
|
||
{
|
||
/* Pull the single step breakpoints out of the target. */
|
||
SOFTWARE_SINGLE_STEP (0, 0);
|
||
singlestep_breakpoints_inserted_p = 0;
|
||
}
|
||
|
||
/* If PC is pointing at a nullified instruction, then step beyond
|
||
it so that the user won't be confused when GDB appears to be ready
|
||
to execute it. */
|
||
|
||
/* if (INSTRUCTION_NULLIFIED && currently_stepping (ecs)) */
|
||
if (INSTRUCTION_NULLIFIED)
|
||
{
|
||
registers_changed ();
|
||
target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
|
||
|
||
/* We may have received a signal that we want to pass to
|
||
the inferior; therefore, we must not clobber the waitstatus
|
||
in WS. */
|
||
|
||
ecs->infwait_state = infwait_nullified_state;
|
||
ecs->waiton_ptid = ecs->ptid;
|
||
ecs->wp = &(ecs->tmpstatus);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
|
||
/* It may not be necessary to disable the watchpoint to stop over
|
||
it. For example, the PA can (with some kernel cooperation)
|
||
single step over a watchpoint without disabling the watchpoint. */
|
||
if (HAVE_STEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
|
||
{
|
||
resume (1, 0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
|
||
/* It is far more common to need to disable a watchpoint to step
|
||
the inferior over it. FIXME. What else might a debug
|
||
register or page protection watchpoint scheme need here? */
|
||
if (HAVE_NONSTEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
|
||
{
|
||
/* At this point, we are stopped at an instruction which has
|
||
attempted to write to a piece of memory under control of
|
||
a watchpoint. The instruction hasn't actually executed
|
||
yet. If we were to evaluate the watchpoint expression
|
||
now, we would get the old value, and therefore no change
|
||
would seem to have occurred.
|
||
|
||
In order to make watchpoints work `right', we really need
|
||
to complete the memory write, and then evaluate the
|
||
watchpoint expression. The following code does that by
|
||
removing the watchpoint (actually, all watchpoints and
|
||
breakpoints), single-stepping the target, re-inserting
|
||
watchpoints, and then falling through to let normal
|
||
single-step processing handle proceed. Since this
|
||
includes evaluating watchpoints, things will come to a
|
||
stop in the correct manner. */
|
||
|
||
remove_breakpoints ();
|
||
registers_changed ();
|
||
target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */
|
||
|
||
ecs->waiton_ptid = ecs->ptid;
|
||
ecs->wp = &(ecs->ws);
|
||
ecs->infwait_state = infwait_nonstep_watch_state;
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
|
||
/* It may be possible to simply continue after a watchpoint. */
|
||
if (HAVE_CONTINUABLE_WATCHPOINT)
|
||
STOPPED_BY_WATCHPOINT (ecs->ws);
|
||
|
||
ecs->stop_func_start = 0;
|
||
ecs->stop_func_end = 0;
|
||
ecs->stop_func_name = 0;
|
||
/* Don't care about return value; stop_func_start and stop_func_name
|
||
will both be 0 if it doesn't work. */
|
||
find_pc_partial_function (stop_pc, &ecs->stop_func_name,
|
||
&ecs->stop_func_start, &ecs->stop_func_end);
|
||
ecs->stop_func_start += FUNCTION_START_OFFSET;
|
||
ecs->another_trap = 0;
|
||
bpstat_clear (&stop_bpstat);
|
||
stop_step = 0;
|
||
stop_stack_dummy = 0;
|
||
stop_print_frame = 1;
|
||
ecs->random_signal = 0;
|
||
stopped_by_random_signal = 0;
|
||
breakpoints_failed = 0;
|
||
|
||
/* Look at the cause of the stop, and decide what to do.
|
||
The alternatives are:
|
||
1) break; to really stop and return to the debugger,
|
||
2) drop through to start up again
|
||
(set ecs->another_trap to 1 to single step once)
|
||
3) set ecs->random_signal to 1, and the decision between 1 and 2
|
||
will be made according to the signal handling tables. */
|
||
|
||
/* First, distinguish signals caused by the debugger from signals
|
||
that have to do with the program's own actions. Note that
|
||
breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
|
||
on the operating system version. Here we detect when a SIGILL or
|
||
SIGEMT is really a breakpoint and change it to SIGTRAP. We do
|
||
something similar for SIGSEGV, since a SIGSEGV will be generated
|
||
when we're trying to execute a breakpoint instruction on a
|
||
non-executable stack. This happens for call dummy breakpoints
|
||
for architectures like SPARC that place call dummies on the
|
||
stack. */
|
||
|
||
if (stop_signal == TARGET_SIGNAL_TRAP
|
||
|| (breakpoints_inserted &&
|
||
(stop_signal == TARGET_SIGNAL_ILL
|
||
|| stop_signal == TARGET_SIGNAL_SEGV
|
||
|| stop_signal == TARGET_SIGNAL_EMT))
|
||
|| stop_soon == STOP_QUIETLY
|
||
|| stop_soon == STOP_QUIETLY_NO_SIGSTOP)
|
||
{
|
||
if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
|
||
{
|
||
stop_print_frame = 0;
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
/* This is originated from start_remote(), start_inferior() and
|
||
shared libraries hook functions. */
|
||
if (stop_soon == STOP_QUIETLY)
|
||
{
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
/* This originates from attach_command(). We need to overwrite
|
||
the stop_signal here, because some kernels don't ignore a
|
||
SIGSTOP in a subsequent ptrace(PTRACE_SONT,SOGSTOP) call.
|
||
See more comments in inferior.h. */
|
||
if (stop_soon == STOP_QUIETLY_NO_SIGSTOP)
|
||
{
|
||
stop_stepping (ecs);
|
||
if (stop_signal == TARGET_SIGNAL_STOP)
|
||
stop_signal = TARGET_SIGNAL_0;
|
||
return;
|
||
}
|
||
|
||
/* Don't even think about breakpoints
|
||
if just proceeded over a breakpoint.
|
||
|
||
However, if we are trying to proceed over a breakpoint
|
||
and end up in sigtramp, then through_sigtramp_breakpoint
|
||
will be set and we should check whether we've hit the
|
||
step breakpoint. */
|
||
if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected
|
||
&& through_sigtramp_breakpoint == NULL)
|
||
bpstat_clear (&stop_bpstat);
|
||
else
|
||
{
|
||
/* See if there is a breakpoint at the current PC. */
|
||
stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
|
||
|
||
/* Following in case break condition called a
|
||
function. */
|
||
stop_print_frame = 1;
|
||
}
|
||
|
||
/* NOTE: cagney/2003-03-29: These two checks for a random signal
|
||
at one stage in the past included checks for an inferior
|
||
function call's call dummy's return breakpoint. The original
|
||
comment, that went with the test, read:
|
||
|
||
``End of a stack dummy. Some systems (e.g. Sony news) give
|
||
another signal besides SIGTRAP, so check here as well as
|
||
above.''
|
||
|
||
If someone ever tries to get get call dummys on a
|
||
non-executable stack to work (where the target would stop
|
||
with something like a SIGSEGV), then those tests might need
|
||
to be re-instated. Given, however, that the tests were only
|
||
enabled when momentary breakpoints were not being used, I
|
||
suspect that it won't be the case.
|
||
|
||
NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
|
||
be necessary for call dummies on a non-executable stack on
|
||
SPARC. */
|
||
|
||
if (stop_signal == TARGET_SIGNAL_TRAP)
|
||
ecs->random_signal
|
||
= !(bpstat_explains_signal (stop_bpstat)
|
||
|| trap_expected
|
||
|| (step_range_end && step_resume_breakpoint == NULL));
|
||
else
|
||
{
|
||
ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
|
||
if (!ecs->random_signal)
|
||
stop_signal = TARGET_SIGNAL_TRAP;
|
||
}
|
||
}
|
||
|
||
/* When we reach this point, we've pretty much decided
|
||
that the reason for stopping must've been a random
|
||
(unexpected) signal. */
|
||
|
||
else
|
||
ecs->random_signal = 1;
|
||
|
||
process_event_stop_test:
|
||
/* For the program's own signals, act according to
|
||
the signal handling tables. */
|
||
|
||
if (ecs->random_signal)
|
||
{
|
||
/* Signal not for debugging purposes. */
|
||
int printed = 0;
|
||
|
||
stopped_by_random_signal = 1;
|
||
|
||
if (signal_print[stop_signal])
|
||
{
|
||
printed = 1;
|
||
target_terminal_ours_for_output ();
|
||
print_stop_reason (SIGNAL_RECEIVED, stop_signal);
|
||
}
|
||
if (signal_stop[stop_signal])
|
||
{
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
/* If not going to stop, give terminal back
|
||
if we took it away. */
|
||
else if (printed)
|
||
target_terminal_inferior ();
|
||
|
||
/* Clear the signal if it should not be passed. */
|
||
if (signal_program[stop_signal] == 0)
|
||
stop_signal = TARGET_SIGNAL_0;
|
||
|
||
/* I'm not sure whether this needs to be check_sigtramp2 or
|
||
whether it could/should be keep_going.
|
||
|
||
This used to jump to step_over_function if we are stepping,
|
||
which is wrong.
|
||
|
||
Suppose the user does a `next' over a function call, and while
|
||
that call is in progress, the inferior receives a signal for
|
||
which GDB does not stop (i.e., signal_stop[SIG] is false). In
|
||
that case, when we reach this point, there is already a
|
||
step-resume breakpoint established, right where it should be:
|
||
immediately after the function call the user is "next"-ing
|
||
over. If we call step_over_function now, two bad things
|
||
happen:
|
||
|
||
- we'll create a new breakpoint, at wherever the current
|
||
frame's return address happens to be. That could be
|
||
anywhere, depending on what function call happens to be on
|
||
the top of the stack at that point. Point is, it's probably
|
||
not where we need it.
|
||
|
||
- the existing step-resume breakpoint (which is at the correct
|
||
address) will get orphaned: step_resume_breakpoint will point
|
||
to the new breakpoint, and the old step-resume breakpoint
|
||
will never be cleaned up.
|
||
|
||
The old behavior was meant to help HP-UX single-step out of
|
||
sigtramps. It would place the new breakpoint at prev_pc, which
|
||
was certainly wrong. I don't know the details there, so fixing
|
||
this probably breaks that. As with anything else, it's up to
|
||
the HP-UX maintainer to furnish a fix that doesn't break other
|
||
platforms. --JimB, 20 May 1999 */
|
||
check_sigtramp2 (ecs);
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* Handle cases caused by hitting a breakpoint. */
|
||
{
|
||
CORE_ADDR jmp_buf_pc;
|
||
struct bpstat_what what;
|
||
|
||
what = bpstat_what (stop_bpstat);
|
||
|
||
if (what.call_dummy)
|
||
{
|
||
stop_stack_dummy = 1;
|
||
#ifdef HP_OS_BUG
|
||
trap_expected_after_continue = 1;
|
||
#endif
|
||
}
|
||
|
||
switch (what.main_action)
|
||
{
|
||
case BPSTAT_WHAT_SET_LONGJMP_RESUME:
|
||
/* If we hit the breakpoint at longjmp, disable it for the
|
||
duration of this command. Then, install a temporary
|
||
breakpoint at the target of the jmp_buf. */
|
||
disable_longjmp_breakpoint ();
|
||
remove_breakpoints ();
|
||
breakpoints_inserted = 0;
|
||
if (!GET_LONGJMP_TARGET_P () || !GET_LONGJMP_TARGET (&jmp_buf_pc))
|
||
{
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* Need to blow away step-resume breakpoint, as it
|
||
interferes with us */
|
||
if (step_resume_breakpoint != NULL)
|
||
{
|
||
delete_step_resume_breakpoint (&step_resume_breakpoint);
|
||
}
|
||
/* Not sure whether we need to blow this away too, but probably
|
||
it is like the step-resume breakpoint. */
|
||
if (through_sigtramp_breakpoint != NULL)
|
||
{
|
||
delete_breakpoint (through_sigtramp_breakpoint);
|
||
through_sigtramp_breakpoint = NULL;
|
||
}
|
||
|
||
#if 0
|
||
/* FIXME - Need to implement nested temporary breakpoints */
|
||
if (step_over_calls > 0)
|
||
set_longjmp_resume_breakpoint (jmp_buf_pc, get_current_frame ());
|
||
else
|
||
#endif /* 0 */
|
||
set_longjmp_resume_breakpoint (jmp_buf_pc, null_frame_id);
|
||
ecs->handling_longjmp = 1; /* FIXME */
|
||
keep_going (ecs);
|
||
return;
|
||
|
||
case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
|
||
case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
|
||
remove_breakpoints ();
|
||
breakpoints_inserted = 0;
|
||
#if 0
|
||
/* FIXME - Need to implement nested temporary breakpoints */
|
||
if (step_over_calls
|
||
&& (frame_id_inner (get_frame_id (get_current_frame ()),
|
||
step_frame_id)))
|
||
{
|
||
ecs->another_trap = 1;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
#endif /* 0 */
|
||
disable_longjmp_breakpoint ();
|
||
ecs->handling_longjmp = 0; /* FIXME */
|
||
if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
|
||
break;
|
||
/* else fallthrough */
|
||
|
||
case BPSTAT_WHAT_SINGLE:
|
||
if (breakpoints_inserted)
|
||
{
|
||
remove_breakpoints ();
|
||
}
|
||
breakpoints_inserted = 0;
|
||
ecs->another_trap = 1;
|
||
/* Still need to check other stuff, at least the case
|
||
where we are stepping and step out of the right range. */
|
||
break;
|
||
|
||
case BPSTAT_WHAT_STOP_NOISY:
|
||
stop_print_frame = 1;
|
||
|
||
/* We are about to nuke the step_resume_breakpoint and
|
||
through_sigtramp_breakpoint via the cleanup chain, so
|
||
no need to worry about it here. */
|
||
|
||
stop_stepping (ecs);
|
||
return;
|
||
|
||
case BPSTAT_WHAT_STOP_SILENT:
|
||
stop_print_frame = 0;
|
||
|
||
/* We are about to nuke the step_resume_breakpoint and
|
||
through_sigtramp_breakpoint via the cleanup chain, so
|
||
no need to worry about it here. */
|
||
|
||
stop_stepping (ecs);
|
||
return;
|
||
|
||
case BPSTAT_WHAT_STEP_RESUME:
|
||
/* This proably demands a more elegant solution, but, yeah
|
||
right...
|
||
|
||
This function's use of the simple variable
|
||
step_resume_breakpoint doesn't seem to accomodate
|
||
simultaneously active step-resume bp's, although the
|
||
breakpoint list certainly can.
|
||
|
||
If we reach here and step_resume_breakpoint is already
|
||
NULL, then apparently we have multiple active
|
||
step-resume bp's. We'll just delete the breakpoint we
|
||
stopped at, and carry on.
|
||
|
||
Correction: what the code currently does is delete a
|
||
step-resume bp, but it makes no effort to ensure that
|
||
the one deleted is the one currently stopped at. MVS */
|
||
|
||
if (step_resume_breakpoint == NULL)
|
||
{
|
||
step_resume_breakpoint =
|
||
bpstat_find_step_resume_breakpoint (stop_bpstat);
|
||
}
|
||
delete_step_resume_breakpoint (&step_resume_breakpoint);
|
||
break;
|
||
|
||
case BPSTAT_WHAT_THROUGH_SIGTRAMP:
|
||
if (through_sigtramp_breakpoint)
|
||
delete_breakpoint (through_sigtramp_breakpoint);
|
||
through_sigtramp_breakpoint = NULL;
|
||
|
||
/* If were waiting for a trap, hitting the step_resume_break
|
||
doesn't count as getting it. */
|
||
if (trap_expected)
|
||
ecs->another_trap = 1;
|
||
break;
|
||
|
||
case BPSTAT_WHAT_CHECK_SHLIBS:
|
||
case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
|
||
#ifdef SOLIB_ADD
|
||
{
|
||
/* Remove breakpoints, we eventually want to step over the
|
||
shlib event breakpoint, and SOLIB_ADD might adjust
|
||
breakpoint addresses via breakpoint_re_set. */
|
||
if (breakpoints_inserted)
|
||
remove_breakpoints ();
|
||
breakpoints_inserted = 0;
|
||
|
||
/* Check for any newly added shared libraries if we're
|
||
supposed to be adding them automatically. Switch
|
||
terminal for any messages produced by
|
||
breakpoint_re_set. */
|
||
target_terminal_ours_for_output ();
|
||
/* NOTE: cagney/2003-11-25: Make certain that the target
|
||
stack's section table is kept up-to-date. Architectures,
|
||
(e.g., PPC64), use the section table to perform
|
||
operations such as address => section name and hence
|
||
require the table to contain all sections (including
|
||
those found in shared libraries). */
|
||
/* NOTE: cagney/2003-11-25: Pass current_target and not
|
||
exec_ops to SOLIB_ADD. This is because current GDB is
|
||
only tooled to propagate section_table changes out from
|
||
the "current_target" (see target_resize_to_sections), and
|
||
not up from the exec stratum. This, of course, isn't
|
||
right. "infrun.c" should only interact with the
|
||
exec/process stratum, instead relying on the target stack
|
||
to propagate relevant changes (stop, section table
|
||
changed, ...) up to other layers. */
|
||
SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
|
||
target_terminal_inferior ();
|
||
|
||
/* Try to reenable shared library breakpoints, additional
|
||
code segments in shared libraries might be mapped in now. */
|
||
re_enable_breakpoints_in_shlibs ();
|
||
|
||
/* If requested, stop when the dynamic linker notifies
|
||
gdb of events. This allows the user to get control
|
||
and place breakpoints in initializer routines for
|
||
dynamically loaded objects (among other things). */
|
||
if (stop_on_solib_events || stop_stack_dummy)
|
||
{
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
/* If we stopped due to an explicit catchpoint, then the
|
||
(see above) call to SOLIB_ADD pulled in any symbols
|
||
from a newly-loaded library, if appropriate.
|
||
|
||
We do want the inferior to stop, but not where it is
|
||
now, which is in the dynamic linker callback. Rather,
|
||
we would like it stop in the user's program, just after
|
||
the call that caused this catchpoint to trigger. That
|
||
gives the user a more useful vantage from which to
|
||
examine their program's state. */
|
||
else if (what.main_action ==
|
||
BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
|
||
{
|
||
/* ??rehrauer: If I could figure out how to get the
|
||
right return PC from here, we could just set a temp
|
||
breakpoint and resume. I'm not sure we can without
|
||
cracking open the dld's shared libraries and sniffing
|
||
their unwind tables and text/data ranges, and that's
|
||
not a terribly portable notion.
|
||
|
||
Until that time, we must step the inferior out of the
|
||
dld callback, and also out of the dld itself (and any
|
||
code or stubs in libdld.sl, such as "shl_load" and
|
||
friends) until we reach non-dld code. At that point,
|
||
we can stop stepping. */
|
||
bpstat_get_triggered_catchpoints (stop_bpstat,
|
||
&ecs->
|
||
stepping_through_solib_catchpoints);
|
||
ecs->stepping_through_solib_after_catch = 1;
|
||
|
||
/* Be sure to lift all breakpoints, so the inferior does
|
||
actually step past this point... */
|
||
ecs->another_trap = 1;
|
||
break;
|
||
}
|
||
else
|
||
{
|
||
/* We want to step over this breakpoint, then keep going. */
|
||
ecs->another_trap = 1;
|
||
break;
|
||
}
|
||
}
|
||
#endif
|
||
break;
|
||
|
||
case BPSTAT_WHAT_LAST:
|
||
/* Not a real code, but listed here to shut up gcc -Wall. */
|
||
|
||
case BPSTAT_WHAT_KEEP_CHECKING:
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* We come here if we hit a breakpoint but should not
|
||
stop for it. Possibly we also were stepping
|
||
and should stop for that. So fall through and
|
||
test for stepping. But, if not stepping,
|
||
do not stop. */
|
||
|
||
/* Are we stepping to get the inferior out of the dynamic
|
||
linker's hook (and possibly the dld itself) after catching
|
||
a shlib event? */
|
||
if (ecs->stepping_through_solib_after_catch)
|
||
{
|
||
#if defined(SOLIB_ADD)
|
||
/* Have we reached our destination? If not, keep going. */
|
||
if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc))
|
||
{
|
||
ecs->another_trap = 1;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
#endif
|
||
/* Else, stop and report the catchpoint(s) whose triggering
|
||
caused us to begin stepping. */
|
||
ecs->stepping_through_solib_after_catch = 0;
|
||
bpstat_clear (&stop_bpstat);
|
||
stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints);
|
||
bpstat_clear (&ecs->stepping_through_solib_catchpoints);
|
||
stop_print_frame = 1;
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
if (step_resume_breakpoint)
|
||
{
|
||
/* Having a step-resume breakpoint overrides anything
|
||
else having to do with stepping commands until
|
||
that breakpoint is reached. */
|
||
/* I'm not sure whether this needs to be check_sigtramp2 or
|
||
whether it could/should be keep_going. */
|
||
check_sigtramp2 (ecs);
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
if (step_range_end == 0)
|
||
{
|
||
/* Likewise if we aren't even stepping. */
|
||
/* I'm not sure whether this needs to be check_sigtramp2 or
|
||
whether it could/should be keep_going. */
|
||
check_sigtramp2 (ecs);
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* If stepping through a line, keep going if still within it.
|
||
|
||
Note that step_range_end is the address of the first instruction
|
||
beyond the step range, and NOT the address of the last instruction
|
||
within it! */
|
||
if (stop_pc >= step_range_start && stop_pc < step_range_end)
|
||
{
|
||
/* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal.
|
||
So definately need to check for sigtramp here. */
|
||
check_sigtramp2 (ecs);
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* We stepped out of the stepping range. */
|
||
|
||
/* If we are stepping at the source level and entered the runtime
|
||
loader dynamic symbol resolution code, we keep on single stepping
|
||
until we exit the run time loader code and reach the callee's
|
||
address. */
|
||
if (step_over_calls == STEP_OVER_UNDEBUGGABLE
|
||
&& IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc))
|
||
{
|
||
CORE_ADDR pc_after_resolver =
|
||
gdbarch_skip_solib_resolver (current_gdbarch, stop_pc);
|
||
|
||
if (pc_after_resolver)
|
||
{
|
||
/* Set up a step-resume breakpoint at the address
|
||
indicated by SKIP_SOLIB_RESOLVER. */
|
||
struct symtab_and_line sr_sal;
|
||
init_sal (&sr_sal);
|
||
sr_sal.pc = pc_after_resolver;
|
||
|
||
check_for_old_step_resume_breakpoint ();
|
||
step_resume_breakpoint =
|
||
set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
|
||
if (breakpoints_inserted)
|
||
insert_breakpoints ();
|
||
}
|
||
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* We can't update step_sp every time through the loop, because
|
||
reading the stack pointer would slow down stepping too much.
|
||
But we can update it every time we leave the step range. */
|
||
ecs->update_step_sp = 1;
|
||
|
||
/* Did we just take a signal? */
|
||
if (pc_in_sigtramp (stop_pc)
|
||
&& !pc_in_sigtramp (prev_pc)
|
||
&& INNER_THAN (read_sp (), step_sp))
|
||
{
|
||
/* We've just taken a signal; go until we are back to
|
||
the point where we took it and one more. */
|
||
|
||
/* Note: The test above succeeds not only when we stepped
|
||
into a signal handler, but also when we step past the last
|
||
statement of a signal handler and end up in the return stub
|
||
of the signal handler trampoline. To distinguish between
|
||
these two cases, check that the frame is INNER_THAN the
|
||
previous one below. pai/1997-09-11 */
|
||
|
||
|
||
{
|
||
struct frame_id current_frame = get_frame_id (get_current_frame ());
|
||
|
||
if (frame_id_inner (current_frame, step_frame_id))
|
||
{
|
||
/* We have just taken a signal; go until we are back to
|
||
the point where we took it and one more. */
|
||
|
||
/* This code is needed at least in the following case:
|
||
The user types "next" and then a signal arrives (before
|
||
the "next" is done). */
|
||
|
||
/* Note that if we are stopped at a breakpoint, then we need
|
||
the step_resume breakpoint to override any breakpoints at
|
||
the same location, so that we will still step over the
|
||
breakpoint even though the signal happened. */
|
||
struct symtab_and_line sr_sal;
|
||
|
||
init_sal (&sr_sal);
|
||
sr_sal.symtab = NULL;
|
||
sr_sal.line = 0;
|
||
sr_sal.pc = prev_pc;
|
||
/* We could probably be setting the frame to
|
||
step_frame_id; I don't think anyone thought to try it. */
|
||
check_for_old_step_resume_breakpoint ();
|
||
step_resume_breakpoint =
|
||
set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
|
||
if (breakpoints_inserted)
|
||
insert_breakpoints ();
|
||
}
|
||
else
|
||
{
|
||
/* We just stepped out of a signal handler and into
|
||
its calling trampoline.
|
||
|
||
Normally, we'd call step_over_function from
|
||
here, but for some reason GDB can't unwind the
|
||
stack correctly to find the real PC for the point
|
||
user code where the signal trampoline will return
|
||
-- FRAME_SAVED_PC fails, at least on HP-UX 10.20.
|
||
But signal trampolines are pretty small stubs of
|
||
code, anyway, so it's OK instead to just
|
||
single-step out. Note: assuming such trampolines
|
||
don't exhibit recursion on any platform... */
|
||
find_pc_partial_function (stop_pc, &ecs->stop_func_name,
|
||
&ecs->stop_func_start,
|
||
&ecs->stop_func_end);
|
||
/* Readjust stepping range */
|
||
step_range_start = ecs->stop_func_start;
|
||
step_range_end = ecs->stop_func_end;
|
||
ecs->stepping_through_sigtramp = 1;
|
||
}
|
||
}
|
||
|
||
|
||
/* If this is stepi or nexti, make sure that the stepping range
|
||
gets us past that instruction. */
|
||
if (step_range_end == 1)
|
||
/* FIXME: Does this run afoul of the code below which, if
|
||
we step into the middle of a line, resets the stepping
|
||
range? */
|
||
step_range_end = (step_range_start = prev_pc) + 1;
|
||
|
||
ecs->remove_breakpoints_on_following_step = 1;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
if (((stop_pc == ecs->stop_func_start /* Quick test */
|
||
|| in_prologue (stop_pc, ecs->stop_func_start))
|
||
&& !IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
|
||
|| IN_SOLIB_CALL_TRAMPOLINE (stop_pc, ecs->stop_func_name)
|
||
|| ecs->stop_func_name == 0)
|
||
{
|
||
/* It's a subroutine call. */
|
||
handle_step_into_function (ecs);
|
||
return;
|
||
}
|
||
|
||
/* We've wandered out of the step range. */
|
||
|
||
ecs->sal = find_pc_line (stop_pc, 0);
|
||
|
||
if (step_range_end == 1)
|
||
{
|
||
/* It is stepi or nexti. We always want to stop stepping after
|
||
one instruction. */
|
||
stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
/* If we're in the return path from a shared library trampoline,
|
||
we want to proceed through the trampoline when stepping. */
|
||
if (IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
|
||
{
|
||
/* Determine where this trampoline returns. */
|
||
CORE_ADDR real_stop_pc = SKIP_TRAMPOLINE_CODE (stop_pc);
|
||
|
||
/* Only proceed through if we know where it's going. */
|
||
if (real_stop_pc)
|
||
{
|
||
/* And put the step-breakpoint there and go until there. */
|
||
struct symtab_and_line sr_sal;
|
||
|
||
init_sal (&sr_sal); /* initialize to zeroes */
|
||
sr_sal.pc = real_stop_pc;
|
||
sr_sal.section = find_pc_overlay (sr_sal.pc);
|
||
/* Do not specify what the fp should be when we stop
|
||
since on some machines the prologue
|
||
is where the new fp value is established. */
|
||
check_for_old_step_resume_breakpoint ();
|
||
step_resume_breakpoint =
|
||
set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
|
||
if (breakpoints_inserted)
|
||
insert_breakpoints ();
|
||
|
||
/* Restart without fiddling with the step ranges or
|
||
other state. */
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
}
|
||
|
||
if (ecs->sal.line == 0)
|
||
{
|
||
/* We have no line number information. That means to stop
|
||
stepping (does this always happen right after one instruction,
|
||
when we do "s" in a function with no line numbers,
|
||
or can this happen as a result of a return or longjmp?). */
|
||
stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
if ((stop_pc == ecs->sal.pc)
|
||
&& (ecs->current_line != ecs->sal.line
|
||
|| ecs->current_symtab != ecs->sal.symtab))
|
||
{
|
||
/* We are at the start of a different line. So stop. Note that
|
||
we don't stop if we step into the middle of a different line.
|
||
That is said to make things like for (;;) statements work
|
||
better. */
|
||
stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
/* We aren't done stepping.
|
||
|
||
Optimize by setting the stepping range to the line.
|
||
(We might not be in the original line, but if we entered a
|
||
new line in mid-statement, we continue stepping. This makes
|
||
things like for(;;) statements work better.) */
|
||
|
||
if (ecs->stop_func_end && ecs->sal.end >= ecs->stop_func_end)
|
||
{
|
||
/* If this is the last line of the function, don't keep stepping
|
||
(it would probably step us out of the function).
|
||
This is particularly necessary for a one-line function,
|
||
in which after skipping the prologue we better stop even though
|
||
we will be in mid-line. */
|
||
stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
step_range_start = ecs->sal.pc;
|
||
step_range_end = ecs->sal.end;
|
||
step_frame_id = get_frame_id (get_current_frame ());
|
||
ecs->current_line = ecs->sal.line;
|
||
ecs->current_symtab = ecs->sal.symtab;
|
||
|
||
/* In the case where we just stepped out of a function into the
|
||
middle of a line of the caller, continue stepping, but
|
||
step_frame_id must be modified to current frame */
|
||
#if 0
|
||
/* NOTE: cagney/2003-10-16: I think this frame ID inner test is too
|
||
generous. It will trigger on things like a step into a frameless
|
||
stackless leaf function. I think the logic should instead look
|
||
at the unwound frame ID has that should give a more robust
|
||
indication of what happened. */
|
||
if (step-ID == current-ID)
|
||
still stepping in same function;
|
||
else if (step-ID == unwind (current-ID))
|
||
stepped into a function;
|
||
else
|
||
stepped out of a function;
|
||
/* Of course this assumes that the frame ID unwind code is robust
|
||
and we're willing to introduce frame unwind logic into this
|
||
function. Fortunately, those days are nearly upon us. */
|
||
#endif
|
||
{
|
||
struct frame_id current_frame = get_frame_id (get_current_frame ());
|
||
if (!(frame_id_inner (current_frame, step_frame_id)))
|
||
step_frame_id = current_frame;
|
||
}
|
||
|
||
keep_going (ecs);
|
||
}
|
||
|
||
/* Are we in the middle of stepping? */
|
||
|
||
static int
|
||
currently_stepping (struct execution_control_state *ecs)
|
||
{
|
||
return ((through_sigtramp_breakpoint == NULL
|
||
&& !ecs->handling_longjmp
|
||
&& ((step_range_end && step_resume_breakpoint == NULL)
|
||
|| trap_expected))
|
||
|| ecs->stepping_through_solib_after_catch
|
||
|| bpstat_should_step ());
|
||
}
|
||
|
||
static void
|
||
check_sigtramp2 (struct execution_control_state *ecs)
|
||
{
|
||
if (trap_expected
|
||
&& pc_in_sigtramp (stop_pc)
|
||
&& !pc_in_sigtramp (prev_pc)
|
||
&& INNER_THAN (read_sp (), step_sp))
|
||
{
|
||
/* What has happened here is that we have just stepped the
|
||
inferior with a signal (because it is a signal which
|
||
shouldn't make us stop), thus stepping into sigtramp.
|
||
|
||
So we need to set a step_resume_break_address breakpoint and
|
||
continue until we hit it, and then step. FIXME: This should
|
||
be more enduring than a step_resume breakpoint; we should
|
||
know that we will later need to keep going rather than
|
||
re-hitting the breakpoint here (see the testsuite,
|
||
gdb.base/signals.exp where it says "exceedingly difficult"). */
|
||
|
||
struct symtab_and_line sr_sal;
|
||
|
||
init_sal (&sr_sal); /* initialize to zeroes */
|
||
sr_sal.pc = prev_pc;
|
||
sr_sal.section = find_pc_overlay (sr_sal.pc);
|
||
/* We perhaps could set the frame if we kept track of what the
|
||
frame corresponding to prev_pc was. But we don't, so don't. */
|
||
through_sigtramp_breakpoint =
|
||
set_momentary_breakpoint (sr_sal, null_frame_id, bp_through_sigtramp);
|
||
if (breakpoints_inserted)
|
||
insert_breakpoints ();
|
||
|
||
ecs->remove_breakpoints_on_following_step = 1;
|
||
ecs->another_trap = 1;
|
||
}
|
||
}
|
||
|
||
/* Subroutine call with source code we should not step over. Do step
|
||
to the first line of code in it. */
|
||
|
||
static void
|
||
step_into_function (struct execution_control_state *ecs)
|
||
{
|
||
struct symtab *s;
|
||
struct symtab_and_line sr_sal;
|
||
|
||
s = find_pc_symtab (stop_pc);
|
||
if (s && s->language != language_asm)
|
||
ecs->stop_func_start = SKIP_PROLOGUE (ecs->stop_func_start);
|
||
|
||
ecs->sal = find_pc_line (ecs->stop_func_start, 0);
|
||
/* Use the step_resume_break to step until the end of the prologue,
|
||
even if that involves jumps (as it seems to on the vax under
|
||
4.2). */
|
||
/* If the prologue ends in the middle of a source line, continue to
|
||
the end of that source line (if it is still within the function).
|
||
Otherwise, just go to end of prologue. */
|
||
if (ecs->sal.end
|
||
&& ecs->sal.pc != ecs->stop_func_start
|
||
&& ecs->sal.end < ecs->stop_func_end)
|
||
ecs->stop_func_start = ecs->sal.end;
|
||
|
||
/* Architectures which require breakpoint adjustment might not be able
|
||
to place a breakpoint at the computed address. If so, the test
|
||
``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
|
||
ecs->stop_func_start to an address at which a breakpoint may be
|
||
legitimately placed.
|
||
|
||
Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
|
||
made, GDB will enter an infinite loop when stepping through
|
||
optimized code consisting of VLIW instructions which contain
|
||
subinstructions corresponding to different source lines. On
|
||
FR-V, it's not permitted to place a breakpoint on any but the
|
||
first subinstruction of a VLIW instruction. When a breakpoint is
|
||
set, GDB will adjust the breakpoint address to the beginning of
|
||
the VLIW instruction. Thus, we need to make the corresponding
|
||
adjustment here when computing the stop address. */
|
||
|
||
if (gdbarch_adjust_breakpoint_address_p (current_gdbarch))
|
||
{
|
||
ecs->stop_func_start
|
||
= gdbarch_adjust_breakpoint_address (current_gdbarch,
|
||
ecs->stop_func_start);
|
||
}
|
||
|
||
if (ecs->stop_func_start == stop_pc)
|
||
{
|
||
/* We are already there: stop now. */
|
||
stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
else
|
||
{
|
||
/* Put the step-breakpoint there and go until there. */
|
||
init_sal (&sr_sal); /* initialize to zeroes */
|
||
sr_sal.pc = ecs->stop_func_start;
|
||
sr_sal.section = find_pc_overlay (ecs->stop_func_start);
|
||
/* Do not specify what the fp should be when we stop since on
|
||
some machines the prologue is where the new fp value is
|
||
established. */
|
||
check_for_old_step_resume_breakpoint ();
|
||
step_resume_breakpoint =
|
||
set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
|
||
if (breakpoints_inserted)
|
||
insert_breakpoints ();
|
||
|
||
/* And make sure stepping stops right away then. */
|
||
step_range_end = step_range_start;
|
||
}
|
||
keep_going (ecs);
|
||
}
|
||
|
||
/* We've just entered a callee, and we wish to resume until it returns
|
||
to the caller. Setting a step_resume breakpoint on the return
|
||
address will catch a return from the callee.
|
||
|
||
However, if the callee is recursing, we want to be careful not to
|
||
catch returns of those recursive calls, but only of THIS instance
|
||
of the call.
|
||
|
||
To do this, we set the step_resume bp's frame to our current
|
||
caller's frame (step_frame_id, which is set by the "next" or
|
||
"until" command, before execution begins). */
|
||
|
||
static void
|
||
step_over_function (struct execution_control_state *ecs)
|
||
{
|
||
struct symtab_and_line sr_sal;
|
||
struct frame_id sr_id;
|
||
|
||
init_sal (&sr_sal); /* initialize to zeros */
|
||
|
||
/* NOTE: cagney/2003-04-06:
|
||
|
||
At this point the equality get_frame_pc() == get_frame_func()
|
||
should hold. This may make it possible for this code to tell the
|
||
frame where it's function is, instead of the reverse. This would
|
||
avoid the need to search for the frame's function, which can get
|
||
very messy when there is no debug info available (look at the
|
||
heuristic find pc start code found in targets like the MIPS). */
|
||
|
||
/* NOTE: cagney/2003-04-06:
|
||
|
||
The intent of DEPRECATED_SAVED_PC_AFTER_CALL was to:
|
||
|
||
- provide a very light weight equivalent to frame_unwind_pc()
|
||
(nee FRAME_SAVED_PC) that avoids the prologue analyzer
|
||
|
||
- avoid handling the case where the PC hasn't been saved in the
|
||
prologue analyzer
|
||
|
||
Unfortunately, not five lines further down, is a call to
|
||
get_frame_id() and that is guarenteed to trigger the prologue
|
||
analyzer.
|
||
|
||
The `correct fix' is for the prologe analyzer to handle the case
|
||
where the prologue is incomplete (PC in prologue) and,
|
||
consequently, the return pc has not yet been saved. It should be
|
||
noted that the prologue analyzer needs to handle this case
|
||
anyway: frameless leaf functions that don't save the return PC;
|
||
single stepping through a prologue.
|
||
|
||
The d10v handles all this by bailing out of the prologue analsis
|
||
when it reaches the current instruction. */
|
||
|
||
if (DEPRECATED_SAVED_PC_AFTER_CALL_P ())
|
||
sr_sal.pc = ADDR_BITS_REMOVE (DEPRECATED_SAVED_PC_AFTER_CALL (get_current_frame ()));
|
||
else
|
||
sr_sal.pc = ADDR_BITS_REMOVE (frame_pc_unwind (get_current_frame ()));
|
||
sr_sal.section = find_pc_overlay (sr_sal.pc);
|
||
|
||
check_for_old_step_resume_breakpoint ();
|
||
|
||
if (frame_id_p (step_frame_id)
|
||
&& !IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
|
||
/* NOTE: cagney/2004-02-27: Use the global state's idea of the
|
||
stepping frame ID. I suspect this is done as it is lighter
|
||
weight than a call to get_prev_frame. */
|
||
sr_id = step_frame_id;
|
||
else if (legacy_frame_p (current_gdbarch))
|
||
/* NOTE: cagney/2004-02-27: This is the way it was 'cos this is
|
||
the way it always was. It should be using the unwound (or
|
||
caller's) ID, and not this (or the callee's) ID. It appeared
|
||
to work because: legacy architectures used the wrong end of the
|
||
frame for the ID.stack (inner-most rather than outer-most) so
|
||
that the callee's id.stack (un adjusted) matched the caller's
|
||
id.stack giving the "correct" id; more often than not
|
||
!IN_SOLIB_DYNSYM_RESOLVE_CODE and hence the code above (it was
|
||
originally later in the function) fixed the ID by using global
|
||
state. */
|
||
sr_id = get_frame_id (get_current_frame ());
|
||
else
|
||
sr_id = get_frame_id (get_prev_frame (get_current_frame ()));
|
||
|
||
step_resume_breakpoint = set_momentary_breakpoint (sr_sal, sr_id, bp_step_resume);
|
||
|
||
if (breakpoints_inserted)
|
||
insert_breakpoints ();
|
||
}
|
||
|
||
static void
|
||
stop_stepping (struct execution_control_state *ecs)
|
||
{
|
||
/* Let callers know we don't want to wait for the inferior anymore. */
|
||
ecs->wait_some_more = 0;
|
||
}
|
||
|
||
/* This function handles various cases where we need to continue
|
||
waiting for the inferior. */
|
||
/* (Used to be the keep_going: label in the old wait_for_inferior) */
|
||
|
||
static void
|
||
keep_going (struct execution_control_state *ecs)
|
||
{
|
||
/* Save the pc before execution, to compare with pc after stop. */
|
||
prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
|
||
|
||
if (ecs->update_step_sp)
|
||
step_sp = read_sp ();
|
||
ecs->update_step_sp = 0;
|
||
|
||
/* If we did not do break;, it means we should keep running the
|
||
inferior and not return to debugger. */
|
||
|
||
if (trap_expected && stop_signal != TARGET_SIGNAL_TRAP)
|
||
{
|
||
/* We took a signal (which we are supposed to pass through to
|
||
the inferior, else we'd have done a break above) and we
|
||
haven't yet gotten our trap. Simply continue. */
|
||
resume (currently_stepping (ecs), stop_signal);
|
||
}
|
||
else
|
||
{
|
||
/* Either the trap was not expected, but we are continuing
|
||
anyway (the user asked that this signal be passed to the
|
||
child)
|
||
-- or --
|
||
The signal was SIGTRAP, e.g. it was our signal, but we
|
||
decided we should resume from it.
|
||
|
||
We're going to run this baby now!
|
||
|
||
Insert breakpoints now, unless we are trying to one-proceed
|
||
past a breakpoint. */
|
||
/* If we've just finished a special step resume and we don't
|
||
want to hit a breakpoint, pull em out. */
|
||
if (step_resume_breakpoint == NULL
|
||
&& through_sigtramp_breakpoint == NULL
|
||
&& ecs->remove_breakpoints_on_following_step)
|
||
{
|
||
ecs->remove_breakpoints_on_following_step = 0;
|
||
remove_breakpoints ();
|
||
breakpoints_inserted = 0;
|
||
}
|
||
else if (!breakpoints_inserted &&
|
||
(through_sigtramp_breakpoint != NULL || !ecs->another_trap))
|
||
{
|
||
breakpoints_failed = insert_breakpoints ();
|
||
if (breakpoints_failed)
|
||
{
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
breakpoints_inserted = 1;
|
||
}
|
||
|
||
trap_expected = ecs->another_trap;
|
||
|
||
/* Do not deliver SIGNAL_TRAP (except when the user explicitly
|
||
specifies that such a signal should be delivered to the
|
||
target program).
|
||
|
||
Typically, this would occure when a user is debugging a
|
||
target monitor on a simulator: the target monitor sets a
|
||
breakpoint; the simulator encounters this break-point and
|
||
halts the simulation handing control to GDB; GDB, noteing
|
||
that the break-point isn't valid, returns control back to the
|
||
simulator; the simulator then delivers the hardware
|
||
equivalent of a SIGNAL_TRAP to the program being debugged. */
|
||
|
||
if (stop_signal == TARGET_SIGNAL_TRAP && !signal_program[stop_signal])
|
||
stop_signal = TARGET_SIGNAL_0;
|
||
|
||
|
||
resume (currently_stepping (ecs), stop_signal);
|
||
}
|
||
|
||
prepare_to_wait (ecs);
|
||
}
|
||
|
||
/* This function normally comes after a resume, before
|
||
handle_inferior_event exits. It takes care of any last bits of
|
||
housekeeping, and sets the all-important wait_some_more flag. */
|
||
|
||
static void
|
||
prepare_to_wait (struct execution_control_state *ecs)
|
||
{
|
||
if (ecs->infwait_state == infwait_normal_state)
|
||
{
|
||
overlay_cache_invalid = 1;
|
||
|
||
/* We have to invalidate the registers BEFORE calling
|
||
target_wait because they can be loaded from the target while
|
||
in target_wait. This makes remote debugging a bit more
|
||
efficient for those targets that provide critical registers
|
||
as part of their normal status mechanism. */
|
||
|
||
registers_changed ();
|
||
ecs->waiton_ptid = pid_to_ptid (-1);
|
||
ecs->wp = &(ecs->ws);
|
||
}
|
||
/* This is the old end of the while loop. Let everybody know we
|
||
want to wait for the inferior some more and get called again
|
||
soon. */
|
||
ecs->wait_some_more = 1;
|
||
}
|
||
|
||
/* Print why the inferior has stopped. We always print something when
|
||
the inferior exits, or receives a signal. The rest of the cases are
|
||
dealt with later on in normal_stop() and print_it_typical(). Ideally
|
||
there should be a call to this function from handle_inferior_event()
|
||
each time stop_stepping() is called.*/
|
||
static void
|
||
print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
|
||
{
|
||
switch (stop_reason)
|
||
{
|
||
case STOP_UNKNOWN:
|
||
/* We don't deal with these cases from handle_inferior_event()
|
||
yet. */
|
||
break;
|
||
case END_STEPPING_RANGE:
|
||
/* We are done with a step/next/si/ni command. */
|
||
/* For now print nothing. */
|
||
/* Print a message only if not in the middle of doing a "step n"
|
||
operation for n > 1 */
|
||
if (!step_multi || !stop_step)
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
ui_out_field_string (uiout, "reason", "end-stepping-range");
|
||
break;
|
||
case BREAKPOINT_HIT:
|
||
/* We found a breakpoint. */
|
||
/* For now print nothing. */
|
||
break;
|
||
case SIGNAL_EXITED:
|
||
/* The inferior was terminated by a signal. */
|
||
annotate_signalled ();
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
ui_out_field_string (uiout, "reason", "exited-signalled");
|
||
ui_out_text (uiout, "\nProgram terminated with signal ");
|
||
annotate_signal_name ();
|
||
ui_out_field_string (uiout, "signal-name",
|
||
target_signal_to_name (stop_info));
|
||
annotate_signal_name_end ();
|
||
ui_out_text (uiout, ", ");
|
||
annotate_signal_string ();
|
||
ui_out_field_string (uiout, "signal-meaning",
|
||
target_signal_to_string (stop_info));
|
||
annotate_signal_string_end ();
|
||
ui_out_text (uiout, ".\n");
|
||
ui_out_text (uiout, "The program no longer exists.\n");
|
||
break;
|
||
case EXITED:
|
||
/* The inferior program is finished. */
|
||
annotate_exited (stop_info);
|
||
if (stop_info)
|
||
{
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
ui_out_field_string (uiout, "reason", "exited");
|
||
ui_out_text (uiout, "\nProgram exited with code ");
|
||
ui_out_field_fmt (uiout, "exit-code", "0%o",
|
||
(unsigned int) stop_info);
|
||
ui_out_text (uiout, ".\n");
|
||
}
|
||
else
|
||
{
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
ui_out_field_string (uiout, "reason", "exited-normally");
|
||
ui_out_text (uiout, "\nProgram exited normally.\n");
|
||
}
|
||
break;
|
||
case SIGNAL_RECEIVED:
|
||
/* Signal received. The signal table tells us to print about
|
||
it. */
|
||
annotate_signal ();
|
||
ui_out_text (uiout, "\nProgram received signal ");
|
||
annotate_signal_name ();
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
ui_out_field_string (uiout, "reason", "signal-received");
|
||
ui_out_field_string (uiout, "signal-name",
|
||
target_signal_to_name (stop_info));
|
||
annotate_signal_name_end ();
|
||
ui_out_text (uiout, ", ");
|
||
annotate_signal_string ();
|
||
ui_out_field_string (uiout, "signal-meaning",
|
||
target_signal_to_string (stop_info));
|
||
annotate_signal_string_end ();
|
||
ui_out_text (uiout, ".\n");
|
||
break;
|
||
default:
|
||
internal_error (__FILE__, __LINE__,
|
||
"print_stop_reason: unrecognized enum value");
|
||
break;
|
||
}
|
||
}
|
||
|
||
|
||
/* Here to return control to GDB when the inferior stops for real.
|
||
Print appropriate messages, remove breakpoints, give terminal our modes.
|
||
|
||
STOP_PRINT_FRAME nonzero means print the executing frame
|
||
(pc, function, args, file, line number and line text).
|
||
BREAKPOINTS_FAILED nonzero means stop was due to error
|
||
attempting to insert breakpoints. */
|
||
|
||
void
|
||
normal_stop (void)
|
||
{
|
||
struct target_waitstatus last;
|
||
ptid_t last_ptid;
|
||
|
||
get_last_target_status (&last_ptid, &last);
|
||
|
||
/* As with the notification of thread events, we want to delay
|
||
notifying the user that we've switched thread context until
|
||
the inferior actually stops.
|
||
|
||
There's no point in saying anything if the inferior has exited.
|
||
Note that SIGNALLED here means "exited with a signal", not
|
||
"received a signal". */
|
||
if (!ptid_equal (previous_inferior_ptid, inferior_ptid)
|
||
&& target_has_execution
|
||
&& last.kind != TARGET_WAITKIND_SIGNALLED
|
||
&& last.kind != TARGET_WAITKIND_EXITED)
|
||
{
|
||
target_terminal_ours_for_output ();
|
||
printf_filtered ("[Switching to %s]\n",
|
||
target_pid_or_tid_to_str (inferior_ptid));
|
||
previous_inferior_ptid = inferior_ptid;
|
||
}
|
||
|
||
/* NOTE drow/2004-01-17: Is this still necessary? */
|
||
/* Make sure that the current_frame's pc is correct. This
|
||
is a correction for setting up the frame info before doing
|
||
DECR_PC_AFTER_BREAK */
|
||
if (target_has_execution)
|
||
/* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
|
||
DECR_PC_AFTER_BREAK, the program counter can change. Ask the
|
||
frame code to check for this and sort out any resultant mess.
|
||
DECR_PC_AFTER_BREAK needs to just go away. */
|
||
deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
|
||
|
||
if (target_has_execution && breakpoints_inserted)
|
||
{
|
||
if (remove_breakpoints ())
|
||
{
|
||
target_terminal_ours_for_output ();
|
||
printf_filtered ("Cannot remove breakpoints because ");
|
||
printf_filtered ("program is no longer writable.\n");
|
||
printf_filtered ("It might be running in another process.\n");
|
||
printf_filtered ("Further execution is probably impossible.\n");
|
||
}
|
||
}
|
||
breakpoints_inserted = 0;
|
||
|
||
/* Delete the breakpoint we stopped at, if it wants to be deleted.
|
||
Delete any breakpoint that is to be deleted at the next stop. */
|
||
|
||
breakpoint_auto_delete (stop_bpstat);
|
||
|
||
/* If an auto-display called a function and that got a signal,
|
||
delete that auto-display to avoid an infinite recursion. */
|
||
|
||
if (stopped_by_random_signal)
|
||
disable_current_display ();
|
||
|
||
/* Don't print a message if in the middle of doing a "step n"
|
||
operation for n > 1 */
|
||
if (step_multi && stop_step)
|
||
goto done;
|
||
|
||
target_terminal_ours ();
|
||
|
||
/* Look up the hook_stop and run it (CLI internally handles problem
|
||
of stop_command's pre-hook not existing). */
|
||
if (stop_command)
|
||
catch_errors (hook_stop_stub, stop_command,
|
||
"Error while running hook_stop:\n", RETURN_MASK_ALL);
|
||
|
||
if (!target_has_stack)
|
||
{
|
||
|
||
goto done;
|
||
}
|
||
|
||
/* Select innermost stack frame - i.e., current frame is frame 0,
|
||
and current location is based on that.
|
||
Don't do this on return from a stack dummy routine,
|
||
or if the program has exited. */
|
||
|
||
if (!stop_stack_dummy)
|
||
{
|
||
select_frame (get_current_frame ());
|
||
|
||
/* Print current location without a level number, if
|
||
we have changed functions or hit a breakpoint.
|
||
Print source line if we have one.
|
||
bpstat_print() contains the logic deciding in detail
|
||
what to print, based on the event(s) that just occurred. */
|
||
|
||
if (stop_print_frame && deprecated_selected_frame)
|
||
{
|
||
int bpstat_ret;
|
||
int source_flag;
|
||
int do_frame_printing = 1;
|
||
|
||
bpstat_ret = bpstat_print (stop_bpstat);
|
||
switch (bpstat_ret)
|
||
{
|
||
case PRINT_UNKNOWN:
|
||
/* FIXME: cagney/2002-12-01: Given that a frame ID does
|
||
(or should) carry around the function and does (or
|
||
should) use that when doing a frame comparison. */
|
||
if (stop_step
|
||
&& frame_id_eq (step_frame_id,
|
||
get_frame_id (get_current_frame ()))
|
||
&& step_start_function == find_pc_function (stop_pc))
|
||
source_flag = SRC_LINE; /* finished step, just print source line */
|
||
else
|
||
source_flag = SRC_AND_LOC; /* print location and source line */
|
||
break;
|
||
case PRINT_SRC_AND_LOC:
|
||
source_flag = SRC_AND_LOC; /* print location and source line */
|
||
break;
|
||
case PRINT_SRC_ONLY:
|
||
source_flag = SRC_LINE;
|
||
break;
|
||
case PRINT_NOTHING:
|
||
source_flag = SRC_LINE; /* something bogus */
|
||
do_frame_printing = 0;
|
||
break;
|
||
default:
|
||
internal_error (__FILE__, __LINE__, "Unknown value.");
|
||
}
|
||
/* For mi, have the same behavior every time we stop:
|
||
print everything but the source line. */
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
source_flag = LOC_AND_ADDRESS;
|
||
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
ui_out_field_int (uiout, "thread-id",
|
||
pid_to_thread_id (inferior_ptid));
|
||
/* The behavior of this routine with respect to the source
|
||
flag is:
|
||
SRC_LINE: Print only source line
|
||
LOCATION: Print only location
|
||
SRC_AND_LOC: Print location and source line */
|
||
if (do_frame_printing)
|
||
print_stack_frame (deprecated_selected_frame, -1, source_flag);
|
||
|
||
/* Display the auto-display expressions. */
|
||
do_displays ();
|
||
}
|
||
}
|
||
|
||
/* Save the function value return registers, if we care.
|
||
We might be about to restore their previous contents. */
|
||
if (proceed_to_finish)
|
||
/* NB: The copy goes through to the target picking up the value of
|
||
all the registers. */
|
||
regcache_cpy (stop_registers, current_regcache);
|
||
|
||
if (stop_stack_dummy)
|
||
{
|
||
/* Pop the empty frame that contains the stack dummy. POP_FRAME
|
||
ends with a setting of the current frame, so we can use that
|
||
next. */
|
||
frame_pop (get_current_frame ());
|
||
/* Set stop_pc to what it was before we called the function.
|
||
Can't rely on restore_inferior_status because that only gets
|
||
called if we don't stop in the called function. */
|
||
stop_pc = read_pc ();
|
||
select_frame (get_current_frame ());
|
||
}
|
||
|
||
done:
|
||
annotate_stopped ();
|
||
observer_notify_normal_stop ();
|
||
}
|
||
|
||
static int
|
||
hook_stop_stub (void *cmd)
|
||
{
|
||
execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
|
||
return (0);
|
||
}
|
||
|
||
int
|
||
signal_stop_state (int signo)
|
||
{
|
||
return signal_stop[signo];
|
||
}
|
||
|
||
int
|
||
signal_print_state (int signo)
|
||
{
|
||
return signal_print[signo];
|
||
}
|
||
|
||
int
|
||
signal_pass_state (int signo)
|
||
{
|
||
return signal_program[signo];
|
||
}
|
||
|
||
int
|
||
signal_stop_update (int signo, int state)
|
||
{
|
||
int ret = signal_stop[signo];
|
||
signal_stop[signo] = state;
|
||
return ret;
|
||
}
|
||
|
||
int
|
||
signal_print_update (int signo, int state)
|
||
{
|
||
int ret = signal_print[signo];
|
||
signal_print[signo] = state;
|
||
return ret;
|
||
}
|
||
|
||
int
|
||
signal_pass_update (int signo, int state)
|
||
{
|
||
int ret = signal_program[signo];
|
||
signal_program[signo] = state;
|
||
return ret;
|
||
}
|
||
|
||
static void
|
||
sig_print_header (void)
|
||
{
|
||
printf_filtered ("\
|
||
Signal Stop\tPrint\tPass to program\tDescription\n");
|
||
}
|
||
|
||
static void
|
||
sig_print_info (enum target_signal oursig)
|
||
{
|
||
char *name = target_signal_to_name (oursig);
|
||
int name_padding = 13 - strlen (name);
|
||
|
||
if (name_padding <= 0)
|
||
name_padding = 0;
|
||
|
||
printf_filtered ("%s", name);
|
||
printf_filtered ("%*.*s ", name_padding, name_padding, " ");
|
||
printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
|
||
printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
|
||
printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
|
||
printf_filtered ("%s\n", target_signal_to_string (oursig));
|
||
}
|
||
|
||
/* Specify how various signals in the inferior should be handled. */
|
||
|
||
static void
|
||
handle_command (char *args, int from_tty)
|
||
{
|
||
char **argv;
|
||
int digits, wordlen;
|
||
int sigfirst, signum, siglast;
|
||
enum target_signal oursig;
|
||
int allsigs;
|
||
int nsigs;
|
||
unsigned char *sigs;
|
||
struct cleanup *old_chain;
|
||
|
||
if (args == NULL)
|
||
{
|
||
error_no_arg ("signal to handle");
|
||
}
|
||
|
||
/* Allocate and zero an array of flags for which signals to handle. */
|
||
|
||
nsigs = (int) TARGET_SIGNAL_LAST;
|
||
sigs = (unsigned char *) alloca (nsigs);
|
||
memset (sigs, 0, nsigs);
|
||
|
||
/* Break the command line up into args. */
|
||
|
||
argv = buildargv (args);
|
||
if (argv == NULL)
|
||
{
|
||
nomem (0);
|
||
}
|
||
old_chain = make_cleanup_freeargv (argv);
|
||
|
||
/* Walk through the args, looking for signal oursigs, signal names, and
|
||
actions. Signal numbers and signal names may be interspersed with
|
||
actions, with the actions being performed for all signals cumulatively
|
||
specified. Signal ranges can be specified as <LOW>-<HIGH>. */
|
||
|
||
while (*argv != NULL)
|
||
{
|
||
wordlen = strlen (*argv);
|
||
for (digits = 0; isdigit ((*argv)[digits]); digits++)
|
||
{;
|
||
}
|
||
allsigs = 0;
|
||
sigfirst = siglast = -1;
|
||
|
||
if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
|
||
{
|
||
/* Apply action to all signals except those used by the
|
||
debugger. Silently skip those. */
|
||
allsigs = 1;
|
||
sigfirst = 0;
|
||
siglast = nsigs - 1;
|
||
}
|
||
else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
|
||
{
|
||
SET_SIGS (nsigs, sigs, signal_stop);
|
||
SET_SIGS (nsigs, sigs, signal_print);
|
||
}
|
||
else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
|
||
{
|
||
UNSET_SIGS (nsigs, sigs, signal_program);
|
||
}
|
||
else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
|
||
{
|
||
SET_SIGS (nsigs, sigs, signal_print);
|
||
}
|
||
else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
|
||
{
|
||
SET_SIGS (nsigs, sigs, signal_program);
|
||
}
|
||
else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
|
||
{
|
||
UNSET_SIGS (nsigs, sigs, signal_stop);
|
||
}
|
||
else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
|
||
{
|
||
SET_SIGS (nsigs, sigs, signal_program);
|
||
}
|
||
else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
|
||
{
|
||
UNSET_SIGS (nsigs, sigs, signal_print);
|
||
UNSET_SIGS (nsigs, sigs, signal_stop);
|
||
}
|
||
else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
|
||
{
|
||
UNSET_SIGS (nsigs, sigs, signal_program);
|
||
}
|
||
else if (digits > 0)
|
||
{
|
||
/* It is numeric. The numeric signal refers to our own
|
||
internal signal numbering from target.h, not to host/target
|
||
signal number. This is a feature; users really should be
|
||
using symbolic names anyway, and the common ones like
|
||
SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
|
||
|
||
sigfirst = siglast = (int)
|
||
target_signal_from_command (atoi (*argv));
|
||
if ((*argv)[digits] == '-')
|
||
{
|
||
siglast = (int)
|
||
target_signal_from_command (atoi ((*argv) + digits + 1));
|
||
}
|
||
if (sigfirst > siglast)
|
||
{
|
||
/* Bet he didn't figure we'd think of this case... */
|
||
signum = sigfirst;
|
||
sigfirst = siglast;
|
||
siglast = signum;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
oursig = target_signal_from_name (*argv);
|
||
if (oursig != TARGET_SIGNAL_UNKNOWN)
|
||
{
|
||
sigfirst = siglast = (int) oursig;
|
||
}
|
||
else
|
||
{
|
||
/* Not a number and not a recognized flag word => complain. */
|
||
error ("Unrecognized or ambiguous flag word: \"%s\".", *argv);
|
||
}
|
||
}
|
||
|
||
/* If any signal numbers or symbol names were found, set flags for
|
||
which signals to apply actions to. */
|
||
|
||
for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
|
||
{
|
||
switch ((enum target_signal) signum)
|
||
{
|
||
case TARGET_SIGNAL_TRAP:
|
||
case TARGET_SIGNAL_INT:
|
||
if (!allsigs && !sigs[signum])
|
||
{
|
||
if (query ("%s is used by the debugger.\n\
|
||
Are you sure you want to change it? ", target_signal_to_name ((enum target_signal) signum)))
|
||
{
|
||
sigs[signum] = 1;
|
||
}
|
||
else
|
||
{
|
||
printf_unfiltered ("Not confirmed, unchanged.\n");
|
||
gdb_flush (gdb_stdout);
|
||
}
|
||
}
|
||
break;
|
||
case TARGET_SIGNAL_0:
|
||
case TARGET_SIGNAL_DEFAULT:
|
||
case TARGET_SIGNAL_UNKNOWN:
|
||
/* Make sure that "all" doesn't print these. */
|
||
break;
|
||
default:
|
||
sigs[signum] = 1;
|
||
break;
|
||
}
|
||
}
|
||
|
||
argv++;
|
||
}
|
||
|
||
target_notice_signals (inferior_ptid);
|
||
|
||
if (from_tty)
|
||
{
|
||
/* Show the results. */
|
||
sig_print_header ();
|
||
for (signum = 0; signum < nsigs; signum++)
|
||
{
|
||
if (sigs[signum])
|
||
{
|
||
sig_print_info (signum);
|
||
}
|
||
}
|
||
}
|
||
|
||
do_cleanups (old_chain);
|
||
}
|
||
|
||
static void
|
||
xdb_handle_command (char *args, int from_tty)
|
||
{
|
||
char **argv;
|
||
struct cleanup *old_chain;
|
||
|
||
/* Break the command line up into args. */
|
||
|
||
argv = buildargv (args);
|
||
if (argv == NULL)
|
||
{
|
||
nomem (0);
|
||
}
|
||
old_chain = make_cleanup_freeargv (argv);
|
||
if (argv[1] != (char *) NULL)
|
||
{
|
||
char *argBuf;
|
||
int bufLen;
|
||
|
||
bufLen = strlen (argv[0]) + 20;
|
||
argBuf = (char *) xmalloc (bufLen);
|
||
if (argBuf)
|
||
{
|
||
int validFlag = 1;
|
||
enum target_signal oursig;
|
||
|
||
oursig = target_signal_from_name (argv[0]);
|
||
memset (argBuf, 0, bufLen);
|
||
if (strcmp (argv[1], "Q") == 0)
|
||
sprintf (argBuf, "%s %s", argv[0], "noprint");
|
||
else
|
||
{
|
||
if (strcmp (argv[1], "s") == 0)
|
||
{
|
||
if (!signal_stop[oursig])
|
||
sprintf (argBuf, "%s %s", argv[0], "stop");
|
||
else
|
||
sprintf (argBuf, "%s %s", argv[0], "nostop");
|
||
}
|
||
else if (strcmp (argv[1], "i") == 0)
|
||
{
|
||
if (!signal_program[oursig])
|
||
sprintf (argBuf, "%s %s", argv[0], "pass");
|
||
else
|
||
sprintf (argBuf, "%s %s", argv[0], "nopass");
|
||
}
|
||
else if (strcmp (argv[1], "r") == 0)
|
||
{
|
||
if (!signal_print[oursig])
|
||
sprintf (argBuf, "%s %s", argv[0], "print");
|
||
else
|
||
sprintf (argBuf, "%s %s", argv[0], "noprint");
|
||
}
|
||
else
|
||
validFlag = 0;
|
||
}
|
||
if (validFlag)
|
||
handle_command (argBuf, from_tty);
|
||
else
|
||
printf_filtered ("Invalid signal handling flag.\n");
|
||
if (argBuf)
|
||
xfree (argBuf);
|
||
}
|
||
}
|
||
do_cleanups (old_chain);
|
||
}
|
||
|
||
/* Print current contents of the tables set by the handle command.
|
||
It is possible we should just be printing signals actually used
|
||
by the current target (but for things to work right when switching
|
||
targets, all signals should be in the signal tables). */
|
||
|
||
static void
|
||
signals_info (char *signum_exp, int from_tty)
|
||
{
|
||
enum target_signal oursig;
|
||
sig_print_header ();
|
||
|
||
if (signum_exp)
|
||
{
|
||
/* First see if this is a symbol name. */
|
||
oursig = target_signal_from_name (signum_exp);
|
||
if (oursig == TARGET_SIGNAL_UNKNOWN)
|
||
{
|
||
/* No, try numeric. */
|
||
oursig =
|
||
target_signal_from_command (parse_and_eval_long (signum_exp));
|
||
}
|
||
sig_print_info (oursig);
|
||
return;
|
||
}
|
||
|
||
printf_filtered ("\n");
|
||
/* These ugly casts brought to you by the native VAX compiler. */
|
||
for (oursig = TARGET_SIGNAL_FIRST;
|
||
(int) oursig < (int) TARGET_SIGNAL_LAST;
|
||
oursig = (enum target_signal) ((int) oursig + 1))
|
||
{
|
||
QUIT;
|
||
|
||
if (oursig != TARGET_SIGNAL_UNKNOWN
|
||
&& oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0)
|
||
sig_print_info (oursig);
|
||
}
|
||
|
||
printf_filtered ("\nUse the \"handle\" command to change these tables.\n");
|
||
}
|
||
|
||
struct inferior_status
|
||
{
|
||
enum target_signal stop_signal;
|
||
CORE_ADDR stop_pc;
|
||
bpstat stop_bpstat;
|
||
int stop_step;
|
||
int stop_stack_dummy;
|
||
int stopped_by_random_signal;
|
||
int trap_expected;
|
||
CORE_ADDR step_range_start;
|
||
CORE_ADDR step_range_end;
|
||
struct frame_id step_frame_id;
|
||
enum step_over_calls_kind step_over_calls;
|
||
CORE_ADDR step_resume_break_address;
|
||
int stop_after_trap;
|
||
int stop_soon;
|
||
struct regcache *stop_registers;
|
||
|
||
/* These are here because if call_function_by_hand has written some
|
||
registers and then decides to call error(), we better not have changed
|
||
any registers. */
|
||
struct regcache *registers;
|
||
|
||
/* A frame unique identifier. */
|
||
struct frame_id selected_frame_id;
|
||
|
||
int breakpoint_proceeded;
|
||
int restore_stack_info;
|
||
int proceed_to_finish;
|
||
};
|
||
|
||
void
|
||
write_inferior_status_register (struct inferior_status *inf_status, int regno,
|
||
LONGEST val)
|
||
{
|
||
int size = DEPRECATED_REGISTER_RAW_SIZE (regno);
|
||
void *buf = alloca (size);
|
||
store_signed_integer (buf, size, val);
|
||
regcache_raw_write (inf_status->registers, regno, buf);
|
||
}
|
||
|
||
/* Save all of the information associated with the inferior<==>gdb
|
||
connection. INF_STATUS is a pointer to a "struct inferior_status"
|
||
(defined in inferior.h). */
|
||
|
||
struct inferior_status *
|
||
save_inferior_status (int restore_stack_info)
|
||
{
|
||
struct inferior_status *inf_status = XMALLOC (struct inferior_status);
|
||
|
||
inf_status->stop_signal = stop_signal;
|
||
inf_status->stop_pc = stop_pc;
|
||
inf_status->stop_step = stop_step;
|
||
inf_status->stop_stack_dummy = stop_stack_dummy;
|
||
inf_status->stopped_by_random_signal = stopped_by_random_signal;
|
||
inf_status->trap_expected = trap_expected;
|
||
inf_status->step_range_start = step_range_start;
|
||
inf_status->step_range_end = step_range_end;
|
||
inf_status->step_frame_id = step_frame_id;
|
||
inf_status->step_over_calls = step_over_calls;
|
||
inf_status->stop_after_trap = stop_after_trap;
|
||
inf_status->stop_soon = stop_soon;
|
||
/* Save original bpstat chain here; replace it with copy of chain.
|
||
If caller's caller is walking the chain, they'll be happier if we
|
||
hand them back the original chain when restore_inferior_status is
|
||
called. */
|
||
inf_status->stop_bpstat = stop_bpstat;
|
||
stop_bpstat = bpstat_copy (stop_bpstat);
|
||
inf_status->breakpoint_proceeded = breakpoint_proceeded;
|
||
inf_status->restore_stack_info = restore_stack_info;
|
||
inf_status->proceed_to_finish = proceed_to_finish;
|
||
|
||
inf_status->stop_registers = regcache_dup_no_passthrough (stop_registers);
|
||
|
||
inf_status->registers = regcache_dup (current_regcache);
|
||
|
||
inf_status->selected_frame_id = get_frame_id (deprecated_selected_frame);
|
||
return inf_status;
|
||
}
|
||
|
||
static int
|
||
restore_selected_frame (void *args)
|
||
{
|
||
struct frame_id *fid = (struct frame_id *) args;
|
||
struct frame_info *frame;
|
||
|
||
frame = frame_find_by_id (*fid);
|
||
|
||
/* If inf_status->selected_frame_id is NULL, there was no previously
|
||
selected frame. */
|
||
if (frame == NULL)
|
||
{
|
||
warning ("Unable to restore previously selected frame.\n");
|
||
return 0;
|
||
}
|
||
|
||
select_frame (frame);
|
||
|
||
return (1);
|
||
}
|
||
|
||
void
|
||
restore_inferior_status (struct inferior_status *inf_status)
|
||
{
|
||
stop_signal = inf_status->stop_signal;
|
||
stop_pc = inf_status->stop_pc;
|
||
stop_step = inf_status->stop_step;
|
||
stop_stack_dummy = inf_status->stop_stack_dummy;
|
||
stopped_by_random_signal = inf_status->stopped_by_random_signal;
|
||
trap_expected = inf_status->trap_expected;
|
||
step_range_start = inf_status->step_range_start;
|
||
step_range_end = inf_status->step_range_end;
|
||
step_frame_id = inf_status->step_frame_id;
|
||
step_over_calls = inf_status->step_over_calls;
|
||
stop_after_trap = inf_status->stop_after_trap;
|
||
stop_soon = inf_status->stop_soon;
|
||
bpstat_clear (&stop_bpstat);
|
||
stop_bpstat = inf_status->stop_bpstat;
|
||
breakpoint_proceeded = inf_status->breakpoint_proceeded;
|
||
proceed_to_finish = inf_status->proceed_to_finish;
|
||
|
||
/* FIXME: Is the restore of stop_registers always needed. */
|
||
regcache_xfree (stop_registers);
|
||
stop_registers = inf_status->stop_registers;
|
||
|
||
/* The inferior can be gone if the user types "print exit(0)"
|
||
(and perhaps other times). */
|
||
if (target_has_execution)
|
||
/* NB: The register write goes through to the target. */
|
||
regcache_cpy (current_regcache, inf_status->registers);
|
||
regcache_xfree (inf_status->registers);
|
||
|
||
/* FIXME: If we are being called after stopping in a function which
|
||
is called from gdb, we should not be trying to restore the
|
||
selected frame; it just prints a spurious error message (The
|
||
message is useful, however, in detecting bugs in gdb (like if gdb
|
||
clobbers the stack)). In fact, should we be restoring the
|
||
inferior status at all in that case? . */
|
||
|
||
if (target_has_stack && inf_status->restore_stack_info)
|
||
{
|
||
/* The point of catch_errors is that if the stack is clobbered,
|
||
walking the stack might encounter a garbage pointer and
|
||
error() trying to dereference it. */
|
||
if (catch_errors
|
||
(restore_selected_frame, &inf_status->selected_frame_id,
|
||
"Unable to restore previously selected frame:\n",
|
||
RETURN_MASK_ERROR) == 0)
|
||
/* Error in restoring the selected frame. Select the innermost
|
||
frame. */
|
||
select_frame (get_current_frame ());
|
||
|
||
}
|
||
|
||
xfree (inf_status);
|
||
}
|
||
|
||
static void
|
||
do_restore_inferior_status_cleanup (void *sts)
|
||
{
|
||
restore_inferior_status (sts);
|
||
}
|
||
|
||
struct cleanup *
|
||
make_cleanup_restore_inferior_status (struct inferior_status *inf_status)
|
||
{
|
||
return make_cleanup (do_restore_inferior_status_cleanup, inf_status);
|
||
}
|
||
|
||
void
|
||
discard_inferior_status (struct inferior_status *inf_status)
|
||
{
|
||
/* See save_inferior_status for info on stop_bpstat. */
|
||
bpstat_clear (&inf_status->stop_bpstat);
|
||
regcache_xfree (inf_status->registers);
|
||
regcache_xfree (inf_status->stop_registers);
|
||
xfree (inf_status);
|
||
}
|
||
|
||
int
|
||
inferior_has_forked (int pid, int *child_pid)
|
||
{
|
||
struct target_waitstatus last;
|
||
ptid_t last_ptid;
|
||
|
||
get_last_target_status (&last_ptid, &last);
|
||
|
||
if (last.kind != TARGET_WAITKIND_FORKED)
|
||
return 0;
|
||
|
||
if (ptid_get_pid (last_ptid) != pid)
|
||
return 0;
|
||
|
||
*child_pid = last.value.related_pid;
|
||
return 1;
|
||
}
|
||
|
||
int
|
||
inferior_has_vforked (int pid, int *child_pid)
|
||
{
|
||
struct target_waitstatus last;
|
||
ptid_t last_ptid;
|
||
|
||
get_last_target_status (&last_ptid, &last);
|
||
|
||
if (last.kind != TARGET_WAITKIND_VFORKED)
|
||
return 0;
|
||
|
||
if (ptid_get_pid (last_ptid) != pid)
|
||
return 0;
|
||
|
||
*child_pid = last.value.related_pid;
|
||
return 1;
|
||
}
|
||
|
||
int
|
||
inferior_has_execd (int pid, char **execd_pathname)
|
||
{
|
||
struct target_waitstatus last;
|
||
ptid_t last_ptid;
|
||
|
||
get_last_target_status (&last_ptid, &last);
|
||
|
||
if (last.kind != TARGET_WAITKIND_EXECD)
|
||
return 0;
|
||
|
||
if (ptid_get_pid (last_ptid) != pid)
|
||
return 0;
|
||
|
||
*execd_pathname = xstrdup (last.value.execd_pathname);
|
||
return 1;
|
||
}
|
||
|
||
/* Oft used ptids */
|
||
ptid_t null_ptid;
|
||
ptid_t minus_one_ptid;
|
||
|
||
/* Create a ptid given the necessary PID, LWP, and TID components. */
|
||
|
||
ptid_t
|
||
ptid_build (int pid, long lwp, long tid)
|
||
{
|
||
ptid_t ptid;
|
||
|
||
ptid.pid = pid;
|
||
ptid.lwp = lwp;
|
||
ptid.tid = tid;
|
||
return ptid;
|
||
}
|
||
|
||
/* Create a ptid from just a pid. */
|
||
|
||
ptid_t
|
||
pid_to_ptid (int pid)
|
||
{
|
||
return ptid_build (pid, 0, 0);
|
||
}
|
||
|
||
/* Fetch the pid (process id) component from a ptid. */
|
||
|
||
int
|
||
ptid_get_pid (ptid_t ptid)
|
||
{
|
||
return ptid.pid;
|
||
}
|
||
|
||
/* Fetch the lwp (lightweight process) component from a ptid. */
|
||
|
||
long
|
||
ptid_get_lwp (ptid_t ptid)
|
||
{
|
||
return ptid.lwp;
|
||
}
|
||
|
||
/* Fetch the tid (thread id) component from a ptid. */
|
||
|
||
long
|
||
ptid_get_tid (ptid_t ptid)
|
||
{
|
||
return ptid.tid;
|
||
}
|
||
|
||
/* ptid_equal() is used to test equality of two ptids. */
|
||
|
||
int
|
||
ptid_equal (ptid_t ptid1, ptid_t ptid2)
|
||
{
|
||
return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp
|
||
&& ptid1.tid == ptid2.tid);
|
||
}
|
||
|
||
/* restore_inferior_ptid() will be used by the cleanup machinery
|
||
to restore the inferior_ptid value saved in a call to
|
||
save_inferior_ptid(). */
|
||
|
||
static void
|
||
restore_inferior_ptid (void *arg)
|
||
{
|
||
ptid_t *saved_ptid_ptr = arg;
|
||
inferior_ptid = *saved_ptid_ptr;
|
||
xfree (arg);
|
||
}
|
||
|
||
/* Save the value of inferior_ptid so that it may be restored by a
|
||
later call to do_cleanups(). Returns the struct cleanup pointer
|
||
needed for later doing the cleanup. */
|
||
|
||
struct cleanup *
|
||
save_inferior_ptid (void)
|
||
{
|
||
ptid_t *saved_ptid_ptr;
|
||
|
||
saved_ptid_ptr = xmalloc (sizeof (ptid_t));
|
||
*saved_ptid_ptr = inferior_ptid;
|
||
return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
|
||
}
|
||
|
||
|
||
static void
|
||
build_infrun (void)
|
||
{
|
||
stop_registers = regcache_xmalloc (current_gdbarch);
|
||
}
|
||
|
||
void
|
||
_initialize_infrun (void)
|
||
{
|
||
int i;
|
||
int numsigs;
|
||
struct cmd_list_element *c;
|
||
|
||
DEPRECATED_REGISTER_GDBARCH_SWAP (stop_registers);
|
||
deprecated_register_gdbarch_swap (NULL, 0, build_infrun);
|
||
|
||
add_info ("signals", signals_info,
|
||
"What debugger does when program gets various signals.\n\
|
||
Specify a signal as argument to print info on that signal only.");
|
||
add_info_alias ("handle", "signals", 0);
|
||
|
||
add_com ("handle", class_run, handle_command,
|
||
concat ("Specify how to handle a signal.\n\
|
||
Args are signals and actions to apply to those signals.\n\
|
||
Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
|
||
from 1-15 are allowed for compatibility with old versions of GDB.\n\
|
||
Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
|
||
The special arg \"all\" is recognized to mean all signals except those\n\
|
||
used by the debugger, typically SIGTRAP and SIGINT.\n", "Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
|
||
\"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
|
||
Stop means reenter debugger if this signal happens (implies print).\n\
|
||
Print means print a message if this signal happens.\n\
|
||
Pass means let program see this signal; otherwise program doesn't know.\n\
|
||
Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
|
||
Pass and Stop may be combined.", NULL));
|
||
if (xdb_commands)
|
||
{
|
||
add_com ("lz", class_info, signals_info,
|
||
"What debugger does when program gets various signals.\n\
|
||
Specify a signal as argument to print info on that signal only.");
|
||
add_com ("z", class_run, xdb_handle_command,
|
||
concat ("Specify how to handle a signal.\n\
|
||
Args are signals and actions to apply to those signals.\n\
|
||
Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
|
||
from 1-15 are allowed for compatibility with old versions of GDB.\n\
|
||
Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
|
||
The special arg \"all\" is recognized to mean all signals except those\n\
|
||
used by the debugger, typically SIGTRAP and SIGINT.\n", "Recognized actions include \"s\" (toggles between stop and nostop), \n\
|
||
\"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
|
||
nopass), \"Q\" (noprint)\n\
|
||
Stop means reenter debugger if this signal happens (implies print).\n\
|
||
Print means print a message if this signal happens.\n\
|
||
Pass means let program see this signal; otherwise program doesn't know.\n\
|
||
Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
|
||
Pass and Stop may be combined.", NULL));
|
||
}
|
||
|
||
if (!dbx_commands)
|
||
stop_command =
|
||
add_cmd ("stop", class_obscure, not_just_help_class_command, "There is no `stop' command, but you can set a hook on `stop'.\n\
|
||
This allows you to set a list of commands to be run each time execution\n\
|
||
of the program stops.", &cmdlist);
|
||
|
||
numsigs = (int) TARGET_SIGNAL_LAST;
|
||
signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
|
||
signal_print = (unsigned char *)
|
||
xmalloc (sizeof (signal_print[0]) * numsigs);
|
||
signal_program = (unsigned char *)
|
||
xmalloc (sizeof (signal_program[0]) * numsigs);
|
||
for (i = 0; i < numsigs; i++)
|
||
{
|
||
signal_stop[i] = 1;
|
||
signal_print[i] = 1;
|
||
signal_program[i] = 1;
|
||
}
|
||
|
||
/* Signals caused by debugger's own actions
|
||
should not be given to the program afterwards. */
|
||
signal_program[TARGET_SIGNAL_TRAP] = 0;
|
||
signal_program[TARGET_SIGNAL_INT] = 0;
|
||
|
||
/* Signals that are not errors should not normally enter the debugger. */
|
||
signal_stop[TARGET_SIGNAL_ALRM] = 0;
|
||
signal_print[TARGET_SIGNAL_ALRM] = 0;
|
||
signal_stop[TARGET_SIGNAL_VTALRM] = 0;
|
||
signal_print[TARGET_SIGNAL_VTALRM] = 0;
|
||
signal_stop[TARGET_SIGNAL_PROF] = 0;
|
||
signal_print[TARGET_SIGNAL_PROF] = 0;
|
||
signal_stop[TARGET_SIGNAL_CHLD] = 0;
|
||
signal_print[TARGET_SIGNAL_CHLD] = 0;
|
||
signal_stop[TARGET_SIGNAL_IO] = 0;
|
||
signal_print[TARGET_SIGNAL_IO] = 0;
|
||
signal_stop[TARGET_SIGNAL_POLL] = 0;
|
||
signal_print[TARGET_SIGNAL_POLL] = 0;
|
||
signal_stop[TARGET_SIGNAL_URG] = 0;
|
||
signal_print[TARGET_SIGNAL_URG] = 0;
|
||
signal_stop[TARGET_SIGNAL_WINCH] = 0;
|
||
signal_print[TARGET_SIGNAL_WINCH] = 0;
|
||
|
||
/* These signals are used internally by user-level thread
|
||
implementations. (See signal(5) on Solaris.) Like the above
|
||
signals, a healthy program receives and handles them as part of
|
||
its normal operation. */
|
||
signal_stop[TARGET_SIGNAL_LWP] = 0;
|
||
signal_print[TARGET_SIGNAL_LWP] = 0;
|
||
signal_stop[TARGET_SIGNAL_WAITING] = 0;
|
||
signal_print[TARGET_SIGNAL_WAITING] = 0;
|
||
signal_stop[TARGET_SIGNAL_CANCEL] = 0;
|
||
signal_print[TARGET_SIGNAL_CANCEL] = 0;
|
||
|
||
#ifdef SOLIB_ADD
|
||
add_show_from_set
|
||
(add_set_cmd ("stop-on-solib-events", class_support, var_zinteger,
|
||
(char *) &stop_on_solib_events,
|
||
"Set stopping for shared library events.\n\
|
||
If nonzero, gdb will give control to the user when the dynamic linker\n\
|
||
notifies gdb of shared library events. The most common event of interest\n\
|
||
to the user would be loading/unloading of a new library.\n", &setlist), &showlist);
|
||
#endif
|
||
|
||
c = add_set_enum_cmd ("follow-fork-mode",
|
||
class_run,
|
||
follow_fork_mode_kind_names, &follow_fork_mode_string,
|
||
"Set debugger response to a program call of fork \
|
||
or vfork.\n\
|
||
A fork or vfork creates a new process. follow-fork-mode can be:\n\
|
||
parent - the original process is debugged after a fork\n\
|
||
child - the new process is debugged after a fork\n\
|
||
The unfollowed process will continue to run.\n\
|
||
By default, the debugger will follow the parent process.", &setlist);
|
||
add_show_from_set (c, &showlist);
|
||
|
||
c = add_set_enum_cmd ("scheduler-locking", class_run, scheduler_enums, /* array of string names */
|
||
&scheduler_mode, /* current mode */
|
||
"Set mode for locking scheduler during execution.\n\
|
||
off == no locking (threads may preempt at any time)\n\
|
||
on == full locking (no thread except the current thread may run)\n\
|
||
step == scheduler locked during every single-step operation.\n\
|
||
In this mode, no other thread may run during a step command.\n\
|
||
Other threads may run while stepping over a function call ('next').", &setlist);
|
||
|
||
set_cmd_sfunc (c, set_schedlock_func); /* traps on target vector */
|
||
add_show_from_set (c, &showlist);
|
||
|
||
c = add_set_cmd ("step-mode", class_run,
|
||
var_boolean, (char *) &step_stop_if_no_debug,
|
||
"Set mode of the step operation. When set, doing a step over a\n\
|
||
function without debug line information will stop at the first\n\
|
||
instruction of that function. Otherwise, the function is skipped and\n\
|
||
the step command stops at a different source line.", &setlist);
|
||
add_show_from_set (c, &showlist);
|
||
|
||
/* ptid initializations */
|
||
null_ptid = ptid_build (0, 0, 0);
|
||
minus_one_ptid = ptid_build (-1, 0, 0);
|
||
inferior_ptid = null_ptid;
|
||
target_last_wait_ptid = minus_one_ptid;
|
||
}
|