e37a6e9c8a
(which is not a Posix signal) if it isn't defined. * tm-linux.h, xm-linux.h, config/linux.m[ht], configure.in: New port to Linux (a free Unix clone for 386 machines).
1935 lines
58 KiB
C
1935 lines
58 KiB
C
/* Start (run) and stop the inferior process, for GDB.
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Copyright 1986, 1987, 1988, 1989, 1991, 1992 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
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/* Notes on the algorithm used in wait_for_inferior to determine if we
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just did a subroutine call when stepping. We have the following
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information at that point:
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Current and previous (just before this step) pc.
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Current and previous sp.
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Current and previous start of current function.
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If the starts of the functions don't match, then
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a) We did a subroutine call.
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In this case, the pc will be at the beginning of a function.
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b) We did a subroutine return.
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Otherwise.
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c) We did a longjmp.
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If we did a longjump, we were doing "nexti", since a next would
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have attempted to skip over the assembly language routine in which
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the longjmp is coded and would have simply been the equivalent of a
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continue. I consider this ok behaivior. We'd like one of two
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things to happen if we are doing a nexti through the longjmp()
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routine: 1) It behaves as a stepi, or 2) It acts like a continue as
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above. Given that this is a special case, and that anybody who
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thinks that the concept of sub calls is meaningful in the context
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of a longjmp, I'll take either one. Let's see what happens.
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Acts like a subroutine return. I can handle that with no problem
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at all.
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-->So: If the current and previous beginnings of the current
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function don't match, *and* the pc is at the start of a function,
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we've done a subroutine call. If the pc is not at the start of a
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function, we *didn't* do a subroutine call.
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-->If the beginnings of the current and previous function do match,
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either:
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a) We just did a recursive call.
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In this case, we would be at the very beginning of a
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function and 1) it will have a prologue (don't jump to
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before prologue, or 2) (we assume here that it doesn't have
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a prologue) there will have been a change in the stack
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pointer over the last instruction. (Ie. it's got to put
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the saved pc somewhere. The stack is the usual place. In
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a recursive call a register is only an option if there's a
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prologue to do something with it. This is even true on
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register window machines; the prologue sets up the new
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window. It might not be true on a register window machine
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where the call instruction moved the register window
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itself. Hmmm. One would hope that the stack pointer would
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also change. If it doesn't, somebody send me a note, and
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I'll work out a more general theory.
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bug-gdb@prep.ai.mit.edu). This is true (albeit slipperly
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so) on all machines I'm aware of:
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m68k: Call changes stack pointer. Regular jumps don't.
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sparc: Recursive calls must have frames and therefor,
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prologues.
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vax: All calls have frames and hence change the
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stack pointer.
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b) We did a return from a recursive call. I don't see that we
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have either the ability or the need to distinguish this
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from an ordinary jump. The stack frame will be printed
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when and if the frame pointer changes; if we are in a
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function without a frame pointer, it's the users own
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lookout.
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c) We did a jump within a function. We assume that this is
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true if we didn't do a recursive call.
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d) We are in no-man's land ("I see no symbols here"). We
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don't worry about this; it will make calls look like simple
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jumps (and the stack frames will be printed when the frame
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pointer moves), which is a reasonably non-violent response.
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*/
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#include "defs.h"
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#include <string.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 "wait.h"
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#include "gdbcore.h"
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#include "command.h"
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#include "terminal.h" /* For #ifdef TIOCGPGRP and new_tty */
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#include "target.h"
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#include <signal.h>
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/* unistd.h is needed to #define X_OK */
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#ifdef USG
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#include <unistd.h>
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#else
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#include <sys/file.h>
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#endif
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#ifdef SET_STACK_LIMIT_HUGE
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#include <sys/time.h>
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#include <sys/resource.h>
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extern int original_stack_limit;
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#endif /* SET_STACK_LIMIT_HUGE */
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/* Prototypes for local functions */
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static void
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signals_info PARAMS ((char *, int));
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static void
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handle_command PARAMS ((char *, int));
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static void
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sig_print_info PARAMS ((int));
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static void
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sig_print_header PARAMS ((void));
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static void
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remove_step_breakpoint PARAMS ((void));
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static void
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insert_step_breakpoint PARAMS ((void));
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static void
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resume PARAMS ((int, int));
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static void
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resume_cleanups PARAMS ((int));
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extern char **environ;
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extern struct target_ops child_ops; /* In inftarg.c */
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/* Sigtramp is a routine that the kernel calls (which then calls the
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signal handler). On most machines it is a library routine that
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is linked into the executable.
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This macro, given a program counter value and the name of the
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function in which that PC resides (which can be null if the
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name is not known), returns nonzero if the PC and name show
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that we are in sigtramp.
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On most machines just see if the name is sigtramp (and if we have
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no name, assume we are not in sigtramp). */
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#if !defined (IN_SIGTRAMP)
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#define IN_SIGTRAMP(pc, name) \
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(name && !strcmp ("_sigtramp", name))
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#endif
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/* GET_LONGJMP_TARGET returns the PC at which longjmp() will resume the
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program. It needs to examine the jmp_buf argument and extract the PC
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from it. The return value is non-zero on success, zero otherwise. */
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#ifndef GET_LONGJMP_TARGET
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#define GET_LONGJMP_TARGET(PC_ADDR) 0
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#endif
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/* Some machines have trampoline code that sits between function callers
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and the actual functions themselves. If this machine doesn't have
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such things, disable their processing. */
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#ifndef SKIP_TRAMPOLINE_CODE
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#define SKIP_TRAMPOLINE_CODE(pc) 0
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#endif
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/* For SVR4 shared libraries, each call goes through a small piece of
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trampoline code in the ".init" section. IN_SOLIB_TRAMPOLINE evaluates
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to nonzero if we are current stopped in one of these. */
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#ifndef IN_SOLIB_TRAMPOLINE
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#define IN_SOLIB_TRAMPOLINE(pc,name) 0
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#endif
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/* Notify other parts of gdb that might care that signal handling may
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have changed for one or more signals. */
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#ifndef NOTICE_SIGNAL_HANDLING_CHANGE
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#define NOTICE_SIGNAL_HANDLING_CHANGE /* No actions */
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#endif
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#ifdef TDESC
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#include "tdesc.h"
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int safe_to_init_tdesc_context = 0;
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extern dc_dcontext_t current_context;
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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 char *signal_stop;
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static char *signal_print;
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static char *signal_program;
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/* Nonzero if breakpoints are now inserted in the inferior. */
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/* Nonstatic for initialization during xxx_create_inferior. FIXME. */
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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 => address for special breakpoint for resuming stepping. */
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static CORE_ADDR step_resume_break_address;
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/* Pointer to orig contents of the byte where the special breakpoint is. */
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static char step_resume_break_shadow[BREAKPOINT_MAX];
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/* Nonzero means the special breakpoint is a duplicate
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so it has not itself been inserted. */
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static int step_resume_break_duplicate;
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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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/* 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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/* 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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int stop_soon_quietly;
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/* Nonzero if pc has been changed by the debugger
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since the inferior stopped. */
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int pc_changed;
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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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char stop_registers[REGISTER_BYTES];
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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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#ifdef NO_SINGLE_STEP
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extern int one_stepped; /* From machine dependent code */
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extern void single_step (); /* Same. */
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#endif /* NO_SINGLE_STEP */
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/* Things to clean up if we QUIT out of resume (). */
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/* ARGSUSED */
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static void
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resume_cleanups (arg)
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int arg;
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{
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normal_stop ();
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}
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/* Resume the inferior, but allow a QUIT. This is useful if the user
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wants to interrupt some lengthy single-stepping operation
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(for child processes, the SIGINT goes to the inferior, and so
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we get a SIGINT random_signal, but for remote debugging and perhaps
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other targets, that's not true).
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STEP nonzero if we should step (zero to continue instead).
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SIG is the signal to give the inferior (zero for none). */
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static void
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resume (step, sig)
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int step;
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int sig;
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{
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struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
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QUIT;
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#ifdef NO_SINGLE_STEP
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if (step) {
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single_step(sig); /* Do it the hard way, w/temp breakpoints */
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step = 0; /* ...and don't ask hardware to do it. */
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}
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#endif
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/* Handle any optimized stores to the inferior NOW... */
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#ifdef DO_DEFERRED_STORES
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DO_DEFERRED_STORES;
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#endif
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target_resume (step, sig);
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discard_cleanups (old_cleanups);
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}
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/* Clear out all variables saying what to do when inferior is continued.
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First do this, then set the ones you want, then call `proceed'. */
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void
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clear_proceed_status ()
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{
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trap_expected = 0;
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step_range_start = 0;
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step_range_end = 0;
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step_frame_address = 0;
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step_over_calls = -1;
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step_resume_break_address = 0;
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stop_after_trap = 0;
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stop_soon_quietly = 0;
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proceed_to_finish = 0;
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breakpoint_proceeded = 1; /* We're about to proceed... */
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/* Discard any remaining commands or status from previous stop. */
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bpstat_clear (&stop_bpstat);
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}
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/* Basic routine for continuing the program in various fashions.
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ADDR is the address to resume at, or -1 for resume where stopped.
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SIGGNAL is the signal to give it, or 0 for none,
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or -1 for act according to how it stopped.
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STEP is nonzero if should trap after one instruction.
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-1 means return after that and print nothing.
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You should probably set various step_... variables
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before calling here, if you are stepping.
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You should call clear_proceed_status before calling proceed. */
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void
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proceed (addr, siggnal, step)
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CORE_ADDR addr;
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int siggnal;
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int step;
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{
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int oneproc = 0;
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if (step > 0)
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step_start_function = find_pc_function (read_pc ());
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if (step < 0)
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stop_after_trap = 1;
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if (addr == (CORE_ADDR)-1)
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{
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/* If there is a breakpoint at the address we will resume at,
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step one instruction before inserting breakpoints
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so that we do not stop right away. */
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if (!pc_changed && breakpoint_here_p (read_pc ()))
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oneproc = 1;
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}
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else
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{
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write_register (PC_REGNUM, addr);
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#ifdef NPC_REGNUM
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write_register (NPC_REGNUM, addr + 4);
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#ifdef NNPC_REGNUM
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write_register (NNPC_REGNUM, addr + 8);
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#endif
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#endif
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}
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if (trap_expected_after_continue)
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{
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/* If (step == 0), a trap will be automatically generated after
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the first instruction is executed. Force step one
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instruction to clear this condition. This should not occur
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if step is nonzero, but it is harmless in that case. */
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oneproc = 1;
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trap_expected_after_continue = 0;
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}
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if (oneproc)
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/* We will get a trace trap after one instruction.
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Continue it automatically and insert breakpoints then. */
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trap_expected = 1;
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else
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{
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int temp = insert_breakpoints ();
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if (temp)
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{
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print_sys_errmsg ("ptrace", temp);
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error ("Cannot insert breakpoints.\n\
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The same program may be running in another process.");
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}
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breakpoints_inserted = 1;
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}
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/* Install inferior's terminal modes. */
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target_terminal_inferior ();
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if (siggnal >= 0)
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stop_signal = siggnal;
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/* If this signal should not be seen by program,
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give it zero. Used for debugging signals. */
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else if (stop_signal < NSIG && !signal_program[stop_signal])
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stop_signal= 0;
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/* Resume inferior. */
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resume (oneproc || step || bpstat_should_step (), stop_signal);
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/* Wait for it to stop (if not standalone)
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and in any case decode why it stopped, and act accordingly. */
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wait_for_inferior ();
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normal_stop ();
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}
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/* Record the pc and sp of the program the last time it stopped.
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These are just used internally by wait_for_inferior, but need
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to be preserved over calls to it and cleared when the inferior
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is started. */
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static CORE_ADDR prev_pc;
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static CORE_ADDR prev_sp;
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static CORE_ADDR prev_func_start;
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static char *prev_func_name;
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/* Start an inferior Unix child process and sets inferior_pid to its pid.
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EXEC_FILE is the file to run.
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ALLARGS is a string containing the arguments to the program.
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ENV is the environment vector to pass. Errors reported with error(). */
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#ifndef SHELL_FILE
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#define SHELL_FILE "/bin/sh"
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#endif
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void
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child_create_inferior (exec_file, allargs, env)
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char *exec_file;
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char *allargs;
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char **env;
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{
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int pid;
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char *shell_command;
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char *shell_file;
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static char default_shell_file[] = SHELL_FILE;
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int len;
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int pending_execs;
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/* Set debug_fork then attach to the child while it sleeps, to debug. */
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static int debug_fork = 0;
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/* This is set to the result of setpgrp, which if vforked, will be visible
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to you in the parent process. It's only used by humans for debugging. */
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static int debug_setpgrp = 657473;
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char **save_our_env;
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/* The user might want tilde-expansion, and in general probably wants
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the program to behave the same way as if run from
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his/her favorite shell. So we let the shell run it for us.
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FIXME, this should probably search the local environment (as
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modified by the setenv command), not the env gdb inherited. */
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shell_file = getenv ("SHELL");
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if (shell_file == NULL)
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shell_file = default_shell_file;
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len = 5 + strlen (exec_file) + 1 + strlen (allargs) + 1 + /*slop*/ 10;
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/* If desired, concat something onto the front of ALLARGS.
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SHELL_COMMAND is the result. */
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#ifdef SHELL_COMMAND_CONCAT
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shell_command = (char *) alloca (strlen (SHELL_COMMAND_CONCAT) + len);
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strcpy (shell_command, SHELL_COMMAND_CONCAT);
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#else
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shell_command = (char *) alloca (len);
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shell_command[0] = '\0';
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#endif
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strcat (shell_command, "exec ");
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strcat (shell_command, exec_file);
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strcat (shell_command, " ");
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strcat (shell_command, allargs);
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/* exec is said to fail if the executable is open. */
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close_exec_file ();
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/* Retain a copy of our environment variables, since the child will
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replace the value of environ and if we're vforked, we have to
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restore it. */
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save_our_env = environ;
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/* Tell the terminal handling subsystem what tty we plan to run on;
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it will just record the information for later. */
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new_tty_prefork (inferior_io_terminal);
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/* It is generally good practice to flush any possible pending stdio
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output prior to doing a fork, to avoid the possibility of both the
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parent and child flushing the same data after the fork. */
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fflush (stdout);
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fflush (stderr);
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#if defined(USG) && !defined(HAVE_VFORK)
|
||
pid = fork ();
|
||
#else
|
||
if (debug_fork)
|
||
pid = fork ();
|
||
else
|
||
pid = vfork ();
|
||
#endif
|
||
|
||
if (pid < 0)
|
||
perror_with_name ("vfork");
|
||
|
||
if (pid == 0)
|
||
{
|
||
if (debug_fork)
|
||
sleep (debug_fork);
|
||
|
||
#ifdef TIOCGPGRP
|
||
/* Run inferior in a separate process group. */
|
||
#ifdef NEED_POSIX_SETPGID
|
||
debug_setpgrp = setpgid (0, 0);
|
||
#else
|
||
#if defined(USG) && !defined(SETPGRP_ARGS)
|
||
debug_setpgrp = setpgrp ();
|
||
#else
|
||
debug_setpgrp = setpgrp (getpid (), getpid ());
|
||
#endif /* USG */
|
||
#endif /* NEED_POSIX_SETPGID */
|
||
if (debug_setpgrp == -1)
|
||
perror("setpgrp failed in child");
|
||
#endif /* TIOCGPGRP */
|
||
|
||
#ifdef SET_STACK_LIMIT_HUGE
|
||
/* Reset the stack limit back to what it was. */
|
||
{
|
||
struct rlimit rlim;
|
||
|
||
getrlimit (RLIMIT_STACK, &rlim);
|
||
rlim.rlim_cur = original_stack_limit;
|
||
setrlimit (RLIMIT_STACK, &rlim);
|
||
}
|
||
#endif /* SET_STACK_LIMIT_HUGE */
|
||
|
||
/* Ask the tty subsystem to switch to the one we specified earlier
|
||
(or to share the current terminal, if none was specified). */
|
||
|
||
new_tty ();
|
||
|
||
/* Changing the signal handlers for the inferior after
|
||
a vfork can also change them for the superior, so we don't mess
|
||
with signals here. See comments in
|
||
initialize_signals for how we get the right signal handlers
|
||
for the inferior. */
|
||
|
||
#ifdef USE_PROC_FS
|
||
proc_set_exec_trap (); /* Use SVR4 /proc interface */
|
||
#else
|
||
call_ptrace (0, 0, 0, 0); /* "Trace me, Dr. Memory!" */
|
||
#endif
|
||
|
||
/* There is no execlpe call, so we have to set the environment
|
||
for our child in the global variable. If we've vforked, this
|
||
clobbers the parent, but environ is restored a few lines down
|
||
in the parent. By the way, yes we do need to look down the
|
||
path to find $SHELL. Rich Pixley says so, and I agree. */
|
||
environ = env;
|
||
execlp (shell_file, shell_file, "-c", shell_command, (char *)0);
|
||
|
||
fprintf (stderr, "Cannot exec %s: %s.\n", shell_file,
|
||
safe_strerror (errno));
|
||
fflush (stderr);
|
||
_exit (0177);
|
||
}
|
||
|
||
/* Restore our environment in case a vforked child clob'd it. */
|
||
environ = save_our_env;
|
||
|
||
/* Now that we have a child process, make it our target. */
|
||
push_target (&child_ops);
|
||
|
||
#ifdef CREATE_INFERIOR_HOOK
|
||
CREATE_INFERIOR_HOOK (pid);
|
||
#endif
|
||
|
||
/* The process was started by the fork that created it,
|
||
but it will have stopped one instruction after execing the shell.
|
||
Here we must get it up to actual execution of the real program. */
|
||
|
||
inferior_pid = pid; /* Needed for wait_for_inferior stuff below */
|
||
|
||
clear_proceed_status ();
|
||
|
||
/* We will get a trace trap after one instruction.
|
||
Continue it automatically. Eventually (after shell does an exec)
|
||
it will get another trace trap. Then insert breakpoints and continue. */
|
||
|
||
#ifdef START_INFERIOR_TRAPS_EXPECTED
|
||
pending_execs = START_INFERIOR_TRAPS_EXPECTED;
|
||
#else
|
||
pending_execs = 2;
|
||
#endif
|
||
|
||
init_wait_for_inferior ();
|
||
|
||
/* Set up the "saved terminal modes" of the inferior
|
||
based on what modes we are starting it with. */
|
||
target_terminal_init ();
|
||
|
||
/* Install inferior's terminal modes. */
|
||
target_terminal_inferior ();
|
||
|
||
while (1)
|
||
{
|
||
stop_soon_quietly = 1; /* Make wait_for_inferior be quiet */
|
||
wait_for_inferior ();
|
||
if (stop_signal != SIGTRAP)
|
||
{
|
||
/* Let shell child handle its own signals in its own way */
|
||
/* FIXME, what if child has exit()ed? Must exit loop somehow */
|
||
resume (0, stop_signal);
|
||
}
|
||
else
|
||
{
|
||
/* We handle SIGTRAP, however; it means child did an exec. */
|
||
if (0 == --pending_execs)
|
||
break;
|
||
resume (0, 0); /* Just make it go on */
|
||
}
|
||
}
|
||
stop_soon_quietly = 0;
|
||
|
||
/* We are now in the child process of interest, having exec'd the
|
||
correct program, and are poised at the first instruction of the
|
||
new program. */
|
||
#ifdef SOLIB_CREATE_INFERIOR_HOOK
|
||
SOLIB_CREATE_INFERIOR_HOOK (pid);
|
||
#endif
|
||
|
||
/* Should this perhaps just be a "proceed" call? FIXME */
|
||
insert_step_breakpoint ();
|
||
breakpoints_failed = insert_breakpoints ();
|
||
if (!breakpoints_failed)
|
||
{
|
||
breakpoints_inserted = 1;
|
||
target_terminal_inferior();
|
||
/* Start the child program going on its first instruction, single-
|
||
stepping if we need to. */
|
||
resume (bpstat_should_step (), 0);
|
||
wait_for_inferior ();
|
||
normal_stop ();
|
||
}
|
||
}
|
||
|
||
/* Start remote-debugging of a machine over a serial link. */
|
||
|
||
void
|
||
start_remote ()
|
||
{
|
||
init_wait_for_inferior ();
|
||
clear_proceed_status ();
|
||
stop_soon_quietly = 1;
|
||
trap_expected = 0;
|
||
wait_for_inferior ();
|
||
normal_stop ();
|
||
}
|
||
|
||
/* Initialize static vars when a new inferior begins. */
|
||
|
||
void
|
||
init_wait_for_inferior ()
|
||
{
|
||
/* These are meaningless until the first time through wait_for_inferior. */
|
||
prev_pc = 0;
|
||
prev_sp = 0;
|
||
prev_func_start = 0;
|
||
prev_func_name = NULL;
|
||
|
||
trap_expected_after_continue = 0;
|
||
breakpoints_inserted = 0;
|
||
mark_breakpoints_out ();
|
||
stop_signal = 0; /* Don't confuse first call to proceed(). */
|
||
}
|
||
|
||
|
||
/* Attach to process PID, then initialize for debugging it
|
||
and wait for the trace-trap that results from attaching. */
|
||
|
||
void
|
||
child_attach (args, from_tty)
|
||
char *args;
|
||
int from_tty;
|
||
{
|
||
char *exec_file;
|
||
int pid;
|
||
|
||
dont_repeat();
|
||
|
||
if (!args)
|
||
error_no_arg ("process-id to attach");
|
||
|
||
#ifndef ATTACH_DETACH
|
||
error ("Can't attach to a process on this machine.");
|
||
#else
|
||
pid = atoi (args);
|
||
|
||
if (pid == getpid()) /* Trying to masturbate? */
|
||
error ("I refuse to debug myself!");
|
||
|
||
if (target_has_execution)
|
||
{
|
||
if (query ("A program is being debugged already. Kill it? "))
|
||
target_kill ();
|
||
else
|
||
error ("Inferior not killed.");
|
||
}
|
||
|
||
exec_file = (char *) get_exec_file (1);
|
||
|
||
if (from_tty)
|
||
{
|
||
printf ("Attaching program: %s pid %d\n",
|
||
exec_file, pid);
|
||
fflush (stdout);
|
||
}
|
||
|
||
attach (pid);
|
||
inferior_pid = pid;
|
||
push_target (&child_ops);
|
||
|
||
mark_breakpoints_out ();
|
||
target_terminal_init ();
|
||
clear_proceed_status ();
|
||
stop_soon_quietly = 1;
|
||
/*proceed (-1, 0, -2);*/
|
||
target_terminal_inferior ();
|
||
wait_for_inferior ();
|
||
#ifdef SOLIB_ADD
|
||
SOLIB_ADD ((char *)0, from_tty, (struct target_ops *)0);
|
||
#endif
|
||
normal_stop ();
|
||
#endif /* ATTACH_DETACH */
|
||
}
|
||
|
||
/* 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 ()
|
||
{
|
||
WAITTYPE w;
|
||
int another_trap;
|
||
int random_signal;
|
||
CORE_ADDR stop_sp;
|
||
CORE_ADDR stop_func_start;
|
||
char *stop_func_name;
|
||
CORE_ADDR prologue_pc, tmp;
|
||
int stop_step_resume_break;
|
||
struct symtab_and_line sal;
|
||
int remove_breakpoints_on_following_step = 0;
|
||
int current_line;
|
||
int handling_longjmp = 0; /* FIXME */
|
||
|
||
sal = find_pc_line(prev_pc, 0);
|
||
current_line = sal.line;
|
||
|
||
while (1)
|
||
{
|
||
/* Clean up saved state that will become invalid. */
|
||
pc_changed = 0;
|
||
flush_cached_frames ();
|
||
registers_changed ();
|
||
|
||
target_wait (&w);
|
||
|
||
#ifdef SIGTRAP_STOP_AFTER_LOAD
|
||
|
||
/* Somebody called load(2), and it gave us a "trap signal after load".
|
||
Ignore it gracefully. */
|
||
|
||
SIGTRAP_STOP_AFTER_LOAD (w);
|
||
#endif
|
||
|
||
/* See if the process still exists; clean up if it doesn't. */
|
||
if (WIFEXITED (w))
|
||
{
|
||
target_terminal_ours (); /* Must do this before mourn anyway */
|
||
if (WEXITSTATUS (w))
|
||
printf_filtered ("\nProgram exited with code 0%o.\n",
|
||
(unsigned int)WEXITSTATUS (w));
|
||
else
|
||
if (!batch_mode())
|
||
printf_filtered ("\nProgram exited normally.\n");
|
||
fflush (stdout);
|
||
target_mourn_inferior ();
|
||
#ifdef NO_SINGLE_STEP
|
||
one_stepped = 0;
|
||
#endif
|
||
stop_print_frame = 0;
|
||
break;
|
||
}
|
||
else if (!WIFSTOPPED (w))
|
||
{
|
||
stop_print_frame = 0;
|
||
stop_signal = WTERMSIG (w);
|
||
target_terminal_ours (); /* Must do this before mourn anyway */
|
||
target_kill (); /* kill mourns as well */
|
||
#ifdef PRINT_RANDOM_SIGNAL
|
||
printf_filtered ("\nProgram terminated: ");
|
||
PRINT_RANDOM_SIGNAL (stop_signal);
|
||
#else
|
||
printf_filtered ("\nProgram terminated with signal %d, %s\n",
|
||
stop_signal, safe_strsignal (stop_signal));
|
||
#endif
|
||
printf_filtered ("The inferior process no longer exists.\n");
|
||
fflush (stdout);
|
||
#ifdef NO_SINGLE_STEP
|
||
one_stepped = 0;
|
||
#endif
|
||
break;
|
||
}
|
||
|
||
#ifdef NO_SINGLE_STEP
|
||
if (one_stepped)
|
||
single_step (0); /* This actually cleans up the ss */
|
||
#endif /* NO_SINGLE_STEP */
|
||
|
||
stop_pc = read_pc ();
|
||
set_current_frame ( create_new_frame (read_register (FP_REGNUM),
|
||
read_pc ()));
|
||
|
||
stop_frame_address = FRAME_FP (get_current_frame ());
|
||
stop_sp = read_register (SP_REGNUM);
|
||
stop_func_start = 0;
|
||
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. */
|
||
(void) find_pc_partial_function (stop_pc, &stop_func_name,
|
||
&stop_func_start);
|
||
stop_func_start += FUNCTION_START_OFFSET;
|
||
another_trap = 0;
|
||
bpstat_clear (&stop_bpstat);
|
||
stop_step = 0;
|
||
stop_stack_dummy = 0;
|
||
stop_print_frame = 1;
|
||
stop_step_resume_break = 0;
|
||
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 another_trap to 1 to single step once)
|
||
3) set random_signal to 1, and the decision between 1 and 2
|
||
will be made according to the signal handling tables. */
|
||
|
||
stop_signal = WSTOPSIG (w);
|
||
|
||
/* 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. */
|
||
|
||
if (stop_signal == SIGTRAP
|
||
|| (breakpoints_inserted &&
|
||
(stop_signal == SIGILL
|
||
#ifdef SIGEMT
|
||
|| stop_signal == SIGEMT
|
||
#endif
|
||
))
|
||
|| stop_soon_quietly)
|
||
{
|
||
if (stop_signal == SIGTRAP && stop_after_trap)
|
||
{
|
||
stop_print_frame = 0;
|
||
break;
|
||
}
|
||
if (stop_soon_quietly)
|
||
break;
|
||
|
||
/* 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 step_resume_break_address
|
||
will be set and we should check whether we've hit the
|
||
step breakpoint. */
|
||
if (stop_signal == SIGTRAP && trap_expected
|
||
&& step_resume_break_address == 0)
|
||
bpstat_clear (&stop_bpstat);
|
||
else
|
||
{
|
||
/* See if there is a breakpoint at the current PC. */
|
||
#if DECR_PC_AFTER_BREAK
|
||
/* Notice the case of stepping through a jump
|
||
that lands just after a breakpoint.
|
||
Don't confuse that with hitting the breakpoint.
|
||
What we check for is that 1) stepping is going on
|
||
and 2) the pc before the last insn does not match
|
||
the address of the breakpoint before the current pc. */
|
||
if (prev_pc == stop_pc - DECR_PC_AFTER_BREAK
|
||
|| !step_range_end
|
||
|| step_resume_break_address
|
||
|| handling_longjmp /* FIXME */)
|
||
#endif /* DECR_PC_AFTER_BREAK not zero */
|
||
{
|
||
/* See if we stopped at the special breakpoint for
|
||
stepping over a subroutine call. If both are zero,
|
||
this wasn't the reason for the stop. */
|
||
if (step_resume_break_address
|
||
&& stop_pc - DECR_PC_AFTER_BREAK
|
||
== step_resume_break_address)
|
||
{
|
||
stop_step_resume_break = 1;
|
||
if (DECR_PC_AFTER_BREAK)
|
||
{
|
||
stop_pc -= DECR_PC_AFTER_BREAK;
|
||
write_register (PC_REGNUM, stop_pc);
|
||
pc_changed = 0;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
stop_bpstat =
|
||
bpstat_stop_status (&stop_pc, stop_frame_address);
|
||
/* Following in case break condition called a
|
||
function. */
|
||
stop_print_frame = 1;
|
||
}
|
||
}
|
||
}
|
||
|
||
if (stop_signal == SIGTRAP)
|
||
random_signal
|
||
= !(bpstat_explains_signal (stop_bpstat)
|
||
|| trap_expected
|
||
|| stop_step_resume_break
|
||
|| PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address)
|
||
|| (step_range_end && !step_resume_break_address));
|
||
else
|
||
{
|
||
random_signal
|
||
= !(bpstat_explains_signal (stop_bpstat)
|
||
|| stop_step_resume_break
|
||
/* End of a stack dummy. Some systems (e.g. Sony
|
||
news) give another signal besides SIGTRAP,
|
||
so check here as well as above. */
|
||
|| PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address)
|
||
);
|
||
if (!random_signal)
|
||
stop_signal = SIGTRAP;
|
||
}
|
||
}
|
||
else
|
||
random_signal = 1;
|
||
|
||
/* For the program's own signals, act according to
|
||
the signal handling tables. */
|
||
|
||
if (random_signal)
|
||
{
|
||
/* Signal not for debugging purposes. */
|
||
int printed = 0;
|
||
|
||
stopped_by_random_signal = 1;
|
||
|
||
if (stop_signal >= NSIG
|
||
|| signal_print[stop_signal])
|
||
{
|
||
printed = 1;
|
||
target_terminal_ours_for_output ();
|
||
#ifdef PRINT_RANDOM_SIGNAL
|
||
PRINT_RANDOM_SIGNAL (stop_signal);
|
||
#else
|
||
printf_filtered ("\nProgram received signal %d, %s\n",
|
||
stop_signal, safe_strsignal (stop_signal));
|
||
#endif /* PRINT_RANDOM_SIGNAL */
|
||
fflush (stdout);
|
||
}
|
||
if (stop_signal >= NSIG
|
||
|| signal_stop[stop_signal])
|
||
break;
|
||
/* If not going to stop, give terminal back
|
||
if we took it away. */
|
||
else if (printed)
|
||
target_terminal_inferior ();
|
||
|
||
/* Note that virtually all the code below does `if !random_signal'.
|
||
Perhaps this code should end with a goto or continue. At least
|
||
one (now fixed) bug was caused by this -- a !random_signal was
|
||
missing in one of the tests below. */
|
||
}
|
||
|
||
/* Handle cases caused by hitting a breakpoint. */
|
||
|
||
if (!random_signal)
|
||
if (bpstat_explains_signal (stop_bpstat))
|
||
{
|
||
CORE_ADDR jmp_buf_pc;
|
||
|
||
switch (stop_bpstat->breakpoint_at->type) /* FIXME */
|
||
{
|
||
/* 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. */
|
||
case bp_longjmp:
|
||
disable_longjmp_breakpoint();
|
||
remove_breakpoints ();
|
||
breakpoints_inserted = 0;
|
||
if (!GET_LONGJMP_TARGET(&jmp_buf_pc)) goto keep_going;
|
||
|
||
/* Need to blow away step-resume breakpoint, as it
|
||
interferes with us */
|
||
remove_step_breakpoint ();
|
||
step_resume_break_address = 0;
|
||
stop_step_resume_break = 0;
|
||
|
||
#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);
|
||
handling_longjmp = 1; /* FIXME */
|
||
goto keep_going;
|
||
|
||
case bp_longjmp_resume:
|
||
remove_breakpoints ();
|
||
breakpoints_inserted = 0;
|
||
#if 0 /* FIXME - Need to implement nested temporary breakpoints */
|
||
if (step_over_calls
|
||
&& (stop_frame_address
|
||
INNER_THAN step_frame_address))
|
||
{
|
||
another_trap = 1;
|
||
goto keep_going;
|
||
}
|
||
#endif /* 0 */
|
||
disable_longjmp_breakpoint();
|
||
handling_longjmp = 0; /* FIXME */
|
||
break;
|
||
|
||
default:
|
||
fprintf(stderr, "Unknown breakpoint type %d\n",
|
||
stop_bpstat->breakpoint_at->type);
|
||
case bp_watchpoint:
|
||
case bp_breakpoint:
|
||
case bp_until:
|
||
case bp_finish:
|
||
/* Does a breakpoint want us to stop? */
|
||
if (bpstat_stop (stop_bpstat))
|
||
{
|
||
stop_print_frame = bpstat_should_print (stop_bpstat);
|
||
goto stop_stepping;
|
||
}
|
||
/* Otherwise, must remove breakpoints and single-step
|
||
to get us past the one we hit. */
|
||
else
|
||
{
|
||
remove_breakpoints ();
|
||
remove_step_breakpoint ();
|
||
breakpoints_inserted = 0;
|
||
another_trap = 1;
|
||
}
|
||
break;
|
||
}
|
||
}
|
||
else if (stop_step_resume_break)
|
||
{
|
||
/* But if we have hit the step-resumption breakpoint,
|
||
remove it. It has done its job getting us here.
|
||
The sp test is to make sure that we don't get hung
|
||
up in recursive calls in functions without frame
|
||
pointers. If the stack pointer isn't outside of
|
||
where the breakpoint was set (within a routine to be
|
||
stepped over), we're in the middle of a recursive
|
||
call. Not true for reg window machines (sparc)
|
||
because the must change frames to call things and
|
||
the stack pointer doesn't have to change if it
|
||
the bp was set in a routine without a frame (pc can
|
||
be stored in some other window).
|
||
|
||
The removal of the sp test is to allow calls to
|
||
alloca. Nasty things were happening. Oh, well,
|
||
gdb can only handle one level deep of lack of
|
||
frame pointer. */
|
||
|
||
/*
|
||
Disable test for step_frame_address match so that we always stop even if the
|
||
frames don't match. Reason: if we hit the step_resume_breakpoint, there is
|
||
no way to temporarily disable it so that we can step past it. If we leave
|
||
the breakpoint in, then we loop forever repeatedly hitting, but never
|
||
getting past the breakpoint. This change keeps nexting over recursive
|
||
function calls from hanging gdb.
|
||
*/
|
||
#if 0
|
||
if (* step_frame_address == 0
|
||
|| (step_frame_address == stop_frame_address))
|
||
#endif
|
||
{
|
||
remove_step_breakpoint ();
|
||
step_resume_break_address = 0;
|
||
|
||
/* If were waiting for a trap, hitting the step_resume_break
|
||
doesn't count as getting it. */
|
||
if (trap_expected)
|
||
another_trap = 1;
|
||
}
|
||
}
|
||
|
||
/* 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. */
|
||
|
||
/* If this is the breakpoint at the end of a stack dummy,
|
||
just stop silently. */
|
||
if (!random_signal
|
||
&& PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address))
|
||
{
|
||
stop_print_frame = 0;
|
||
stop_stack_dummy = 1;
|
||
#ifdef HP_OS_BUG
|
||
trap_expected_after_continue = 1;
|
||
#endif
|
||
break;
|
||
}
|
||
|
||
if (step_resume_break_address)
|
||
/* Having a step-resume breakpoint overrides anything
|
||
else having to do with stepping commands until
|
||
that breakpoint is reached. */
|
||
;
|
||
/* If stepping through a line, keep going if still within it. */
|
||
else if (!random_signal
|
||
&& step_range_end
|
||
&& stop_pc >= step_range_start
|
||
&& stop_pc < step_range_end
|
||
/* The step range might include the start of the
|
||
function, so if we are at the start of the
|
||
step range and either the stack or frame pointers
|
||
just changed, we've stepped outside */
|
||
&& !(stop_pc == step_range_start
|
||
&& stop_frame_address
|
||
&& (stop_sp INNER_THAN prev_sp
|
||
|| stop_frame_address != step_frame_address)))
|
||
{
|
||
;
|
||
}
|
||
|
||
/* We stepped out of the stepping range. See if that was due
|
||
to a subroutine call that we should proceed to the end of. */
|
||
else if (!random_signal && step_range_end)
|
||
{
|
||
if (stop_func_start)
|
||
{
|
||
prologue_pc = stop_func_start;
|
||
SKIP_PROLOGUE (prologue_pc);
|
||
}
|
||
|
||
/* Did we just take a signal? */
|
||
if (IN_SIGTRAMP (stop_pc, stop_func_name)
|
||
&& !IN_SIGTRAMP (prev_pc, prev_func_name))
|
||
{
|
||
/* This code is needed at least in the following case:
|
||
The user types "next" and then a signal arrives (before
|
||
the "next" is done). */
|
||
/* We've just taken a signal; go until we are back to
|
||
the point where we took it and one more. */
|
||
step_resume_break_address = prev_pc;
|
||
step_resume_break_duplicate =
|
||
breakpoint_here_p (step_resume_break_address);
|
||
if (breakpoints_inserted)
|
||
insert_step_breakpoint ();
|
||
/* Make sure that the stepping range gets us past
|
||
that instruction. */
|
||
if (step_range_end == 1)
|
||
step_range_end = (step_range_start = prev_pc) + 1;
|
||
remove_breakpoints_on_following_step = 1;
|
||
goto save_pc;
|
||
}
|
||
|
||
/* ==> See comments at top of file on this algorithm. <==*/
|
||
|
||
if ((stop_pc == stop_func_start
|
||
|| IN_SOLIB_TRAMPOLINE (stop_pc, stop_func_name))
|
||
&& (stop_func_start != prev_func_start
|
||
|| prologue_pc != stop_func_start
|
||
|| stop_sp != prev_sp))
|
||
{
|
||
/* It's a subroutine call.
|
||
(0) If we are not stepping over any calls ("stepi"), we
|
||
just stop.
|
||
(1) If we're doing a "next", we want to continue through
|
||
the call ("step over the call").
|
||
(2) If we are in a function-call trampoline (a stub between
|
||
the calling routine and the real function), locate
|
||
the real function and change stop_func_start.
|
||
(3) If we're doing a "step", and there are no debug symbols
|
||
at the target of the call, we want to continue through
|
||
it ("step over the call").
|
||
(4) Otherwise, we want to stop soon, after the function
|
||
prologue ("step into the call"). */
|
||
|
||
if (step_over_calls == 0)
|
||
{
|
||
/* I presume that step_over_calls is only 0 when we're
|
||
supposed to be stepping at the assembly language level. */
|
||
stop_step = 1;
|
||
break;
|
||
}
|
||
|
||
if (step_over_calls > 0)
|
||
goto step_over_function;
|
||
|
||
tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
|
||
if (tmp != 0)
|
||
stop_func_start = tmp;
|
||
|
||
if (find_pc_function (stop_func_start) != 0)
|
||
goto step_into_function;
|
||
|
||
step_over_function:
|
||
/* A subroutine call has happened. */
|
||
/* Set a special breakpoint after the return */
|
||
step_resume_break_address =
|
||
ADDR_BITS_REMOVE
|
||
(SAVED_PC_AFTER_CALL (get_current_frame ()));
|
||
step_resume_break_duplicate
|
||
= breakpoint_here_p (step_resume_break_address);
|
||
if (breakpoints_inserted)
|
||
insert_step_breakpoint ();
|
||
goto save_pc;
|
||
|
||
step_into_function:
|
||
/* Subroutine call with source code we should not step over.
|
||
Do step to the first line of code in it. */
|
||
SKIP_PROLOGUE (stop_func_start);
|
||
sal = find_pc_line (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.
|
||
Otherwise, just go to end of prologue. */
|
||
#ifdef PROLOGUE_FIRSTLINE_OVERLAP
|
||
/* no, don't either. It skips any code that's
|
||
legitimately on the first line. */
|
||
#else
|
||
if (sal.end && sal.pc != stop_func_start)
|
||
stop_func_start = sal.end;
|
||
#endif
|
||
|
||
if (stop_func_start == stop_pc)
|
||
{
|
||
/* We are already there: stop now. */
|
||
stop_step = 1;
|
||
break;
|
||
}
|
||
else
|
||
/* Put the step-breakpoint there and go until there. */
|
||
{
|
||
step_resume_break_address = stop_func_start;
|
||
|
||
step_resume_break_duplicate
|
||
= breakpoint_here_p (step_resume_break_address);
|
||
if (breakpoints_inserted)
|
||
insert_step_breakpoint ();
|
||
/* 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. */
|
||
step_frame_address = 0;
|
||
/* And make sure stepping stops right away then. */
|
||
step_range_end = step_range_start;
|
||
}
|
||
goto save_pc;
|
||
}
|
||
|
||
/* We've wandered out of the step range (but haven't done a
|
||
subroutine call or return). */
|
||
|
||
sal = find_pc_line(stop_pc, 0);
|
||
|
||
if (step_range_end == 1 || /* stepi or nexti */
|
||
sal.line == 0 || /* ...or no line # info */
|
||
(stop_pc == sal.pc /* ...or we're at the start */
|
||
&& current_line != sal.line)) { /* of a different line */
|
||
/* Stop because we're done stepping. */
|
||
stop_step = 1;
|
||
break;
|
||
} else {
|
||
/* We aren't done stepping, and we have line number info for $pc.
|
||
Optimize by setting the step_range for 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.) */
|
||
step_range_start = sal.pc;
|
||
step_range_end = sal.end;
|
||
goto save_pc;
|
||
}
|
||
/* We never fall through here */
|
||
}
|
||
|
||
if (trap_expected
|
||
&& IN_SIGTRAMP (stop_pc, stop_func_name)
|
||
&& !IN_SIGTRAMP (prev_pc, prev_func_name))
|
||
{
|
||
/* 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. */
|
||
step_resume_break_address = prev_pc;
|
||
/* Always 1, I think, but it's probably easier to have
|
||
the step_resume_break as usual rather than trying to
|
||
re-use the breakpoint which is already there. */
|
||
step_resume_break_duplicate =
|
||
breakpoint_here_p (step_resume_break_address);
|
||
if (breakpoints_inserted)
|
||
insert_step_breakpoint ();
|
||
remove_breakpoints_on_following_step = 1;
|
||
another_trap = 1;
|
||
}
|
||
|
||
/* My apologies to the gods of structured programming. */
|
||
/* Come to this label when you need to resume the inferior. It's really much
|
||
cleaner at this time to do a goto than to try and figure out what the
|
||
if-else chain ought to look like!! */
|
||
|
||
keep_going:
|
||
|
||
save_pc:
|
||
/* Save the pc before execution, to compare with pc after stop. */
|
||
prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
|
||
prev_func_start = stop_func_start; /* Ok, since if DECR_PC_AFTER
|
||
BREAK is defined, the
|
||
original pc would not have
|
||
been at the start of a
|
||
function. */
|
||
prev_func_name = stop_func_name;
|
||
prev_sp = stop_sp;
|
||
|
||
/* If we did not do break;, it means we should keep
|
||
running the inferior and not return to debugger. */
|
||
|
||
if (trap_expected && stop_signal != SIGTRAP)
|
||
{
|
||
/* 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 ((step_range_end && !step_resume_break_address)
|
||
|| (trap_expected && !step_resume_break_address)
|
||
|| bpstat_should_step (),
|
||
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_break_address &&
|
||
remove_breakpoints_on_following_step)
|
||
{
|
||
remove_breakpoints_on_following_step = 0;
|
||
remove_breakpoints ();
|
||
breakpoints_inserted = 0;
|
||
}
|
||
else if (!breakpoints_inserted &&
|
||
(step_resume_break_address != 0 || !another_trap))
|
||
{
|
||
insert_step_breakpoint ();
|
||
breakpoints_failed = insert_breakpoints ();
|
||
if (breakpoints_failed)
|
||
break;
|
||
breakpoints_inserted = 1;
|
||
}
|
||
|
||
trap_expected = another_trap;
|
||
|
||
if (stop_signal == SIGTRAP)
|
||
stop_signal = 0;
|
||
|
||
#ifdef SHIFT_INST_REGS
|
||
/* I'm not sure when this following segment applies. I do know, now,
|
||
that we shouldn't rewrite the regs when we were stopped by a
|
||
random signal from the inferior process. */
|
||
|
||
if (!bpstat_explains_signal (stop_bpstat)
|
||
&& (stop_signal != SIGCLD)
|
||
&& !stopped_by_random_signal)
|
||
{
|
||
CORE_ADDR pc_contents = read_register (PC_REGNUM);
|
||
CORE_ADDR npc_contents = read_register (NPC_REGNUM);
|
||
if (pc_contents != npc_contents)
|
||
{
|
||
write_register (NNPC_REGNUM, npc_contents);
|
||
write_register (NPC_REGNUM, pc_contents);
|
||
}
|
||
}
|
||
#endif /* SHIFT_INST_REGS */
|
||
|
||
resume ((!step_resume_break_address
|
||
&& !handling_longjmp
|
||
&& (step_range_end
|
||
|| trap_expected))
|
||
|| bpstat_should_step (),
|
||
stop_signal);
|
||
}
|
||
}
|
||
|
||
stop_stepping:
|
||
if (target_has_execution)
|
||
{
|
||
/* Assuming the inferior still exists, set these up for next
|
||
time, just like we did above if we didn't break out of the
|
||
loop. */
|
||
prev_pc = read_pc ();
|
||
prev_func_start = stop_func_start;
|
||
prev_func_name = stop_func_name;
|
||
prev_sp = stop_sp;
|
||
}
|
||
}
|
||
|
||
/* 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 ()
|
||
{
|
||
/* 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)
|
||
(get_current_frame ())->pc = read_pc ();
|
||
|
||
if (breakpoints_failed)
|
||
{
|
||
target_terminal_ours_for_output ();
|
||
print_sys_errmsg ("ptrace", breakpoints_failed);
|
||
printf_filtered ("Stopped; cannot insert breakpoints.\n\
|
||
The same program may be running in another process.\n");
|
||
}
|
||
|
||
if (target_has_execution)
|
||
remove_step_breakpoint ();
|
||
|
||
if (target_has_execution && breakpoints_inserted)
|
||
if (remove_breakpoints ())
|
||
{
|
||
target_terminal_ours_for_output ();
|
||
printf_filtered ("Cannot remove breakpoints because program is no longer writable.\n\
|
||
It might be running in another process.\n\
|
||
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 ();
|
||
|
||
if (step_multi && stop_step)
|
||
return;
|
||
|
||
target_terminal_ours ();
|
||
|
||
if (!target_has_stack)
|
||
return;
|
||
|
||
/* Select innermost stack frame except on return from a stack dummy routine,
|
||
or if the program has exited. Print it without a level number if
|
||
we have changed functions or hit a breakpoint. Print source line
|
||
if we have one. */
|
||
if (!stop_stack_dummy)
|
||
{
|
||
select_frame (get_current_frame (), 0);
|
||
|
||
if (stop_print_frame)
|
||
{
|
||
int source_only;
|
||
|
||
source_only = bpstat_print (stop_bpstat);
|
||
source_only = source_only ||
|
||
( stop_step
|
||
&& step_frame_address == stop_frame_address
|
||
&& step_start_function == find_pc_function (stop_pc));
|
||
|
||
print_stack_frame (selected_frame, -1, source_only? -1: 1);
|
||
|
||
/* 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)
|
||
read_register_bytes (0, stop_registers, REGISTER_BYTES);
|
||
|
||
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. */
|
||
POP_FRAME;
|
||
select_frame (get_current_frame (), 0);
|
||
}
|
||
}
|
||
|
||
static void
|
||
insert_step_breakpoint ()
|
||
{
|
||
if (step_resume_break_address && !step_resume_break_duplicate)
|
||
target_insert_breakpoint (step_resume_break_address,
|
||
step_resume_break_shadow);
|
||
}
|
||
|
||
static void
|
||
remove_step_breakpoint ()
|
||
{
|
||
if (step_resume_break_address && !step_resume_break_duplicate)
|
||
target_remove_breakpoint (step_resume_break_address,
|
||
step_resume_break_shadow);
|
||
}
|
||
|
||
int signal_stop_state (signo)
|
||
int signo;
|
||
{
|
||
return ((signo >= 0 && signo < NSIG) ? signal_stop[signo] : 0);
|
||
}
|
||
|
||
int signal_print_state (signo)
|
||
int signo;
|
||
{
|
||
return ((signo >= 0 && signo < NSIG) ? signal_print[signo] : 0);
|
||
}
|
||
|
||
int signal_pass_state (signo)
|
||
int signo;
|
||
{
|
||
return ((signo >= 0 && signo < NSIG) ? signal_program[signo] : 0);
|
||
}
|
||
|
||
static void
|
||
sig_print_header ()
|
||
{
|
||
printf_filtered ("Signal\t\tStop\tPrint\tPass to program\tDescription\n");
|
||
}
|
||
|
||
static void
|
||
sig_print_info (number)
|
||
int number;
|
||
{
|
||
char *name;
|
||
|
||
if ((name = strsigno (number)) == NULL)
|
||
printf_filtered ("%d\t\t", number);
|
||
else
|
||
printf_filtered ("%s (%d)\t", name, number);
|
||
printf_filtered ("%s\t", signal_stop[number] ? "Yes" : "No");
|
||
printf_filtered ("%s\t", signal_print[number] ? "Yes" : "No");
|
||
printf_filtered ("%s\t\t", signal_program[number] ? "Yes" : "No");
|
||
printf_filtered ("%s\n", safe_strsignal (number));
|
||
}
|
||
|
||
/* Specify how various signals in the inferior should be handled. */
|
||
|
||
static void
|
||
handle_command (args, from_tty)
|
||
char *args;
|
||
int from_tty;
|
||
{
|
||
register char *p = args;
|
||
int signum = 0;
|
||
register int digits, wordlen;
|
||
char *nextarg;
|
||
|
||
if (!args)
|
||
error_no_arg ("signal to handle");
|
||
|
||
while (*p)
|
||
{
|
||
/* Find the end of the next word in the args. */
|
||
for (wordlen = 0;
|
||
p[wordlen] && p[wordlen] != ' ' && p[wordlen] != '\t';
|
||
wordlen++);
|
||
/* Set nextarg to the start of the word after the one we just
|
||
found, and null-terminate this one. */
|
||
if (p[wordlen] == '\0')
|
||
nextarg = p + wordlen;
|
||
else
|
||
{
|
||
p[wordlen] = '\0';
|
||
nextarg = p + wordlen + 1;
|
||
}
|
||
|
||
|
||
for (digits = 0; p[digits] >= '0' && p[digits] <= '9'; digits++);
|
||
|
||
if (signum == 0)
|
||
{
|
||
/* It is the first argument--must be the signal to operate on. */
|
||
if (digits == wordlen)
|
||
{
|
||
/* Numeric. */
|
||
signum = atoi (p);
|
||
if (signum <= 0 || signum > signo_max ())
|
||
{
|
||
p[wordlen] = '\0';
|
||
error ("Invalid signal %s given as argument to \"handle\".", p);
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* Symbolic. */
|
||
signum = strtosigno (p);
|
||
if (signum == 0)
|
||
error ("No such signal \"%s\"", p);
|
||
}
|
||
|
||
if (signum == SIGTRAP || signum == SIGINT)
|
||
{
|
||
if (!query ("%s is used by the debugger.\nAre you sure you want to change it? ", strsigno (signum)))
|
||
error ("Not confirmed.");
|
||
}
|
||
}
|
||
/* Else, if already got a signal number, look for flag words
|
||
saying what to do for it. */
|
||
else if (!strncmp (p, "stop", wordlen))
|
||
{
|
||
signal_stop[signum] = 1;
|
||
signal_print[signum] = 1;
|
||
}
|
||
else if (wordlen >= 2 && !strncmp (p, "print", wordlen))
|
||
signal_print[signum] = 1;
|
||
else if (wordlen >= 2 && !strncmp (p, "pass", wordlen))
|
||
signal_program[signum] = 1;
|
||
else if (!strncmp (p, "ignore", wordlen))
|
||
signal_program[signum] = 0;
|
||
else if (wordlen >= 3 && !strncmp (p, "nostop", wordlen))
|
||
signal_stop[signum] = 0;
|
||
else if (wordlen >= 4 && !strncmp (p, "noprint", wordlen))
|
||
{
|
||
signal_print[signum] = 0;
|
||
signal_stop[signum] = 0;
|
||
}
|
||
else if (wordlen >= 4 && !strncmp (p, "nopass", wordlen))
|
||
signal_program[signum] = 0;
|
||
else if (wordlen >= 3 && !strncmp (p, "noignore", wordlen))
|
||
signal_program[signum] = 1;
|
||
/* Not a number and not a recognized flag word => complain. */
|
||
else
|
||
{
|
||
error ("Unrecognized or ambiguous flag word: \"%s\".", p);
|
||
}
|
||
|
||
/* Find start of next word. */
|
||
p = nextarg;
|
||
while (*p == ' ' || *p == '\t') p++;
|
||
}
|
||
|
||
NOTICE_SIGNAL_HANDLING_CHANGE;
|
||
|
||
if (from_tty)
|
||
{
|
||
/* Show the results. */
|
||
sig_print_header ();
|
||
sig_print_info (signum);
|
||
}
|
||
}
|
||
|
||
/* Print current contents of the tables set by the handle command. */
|
||
|
||
static void
|
||
signals_info (signum_exp, from_tty)
|
||
char *signum_exp;
|
||
int from_tty;
|
||
{
|
||
register int i;
|
||
sig_print_header ();
|
||
|
||
if (signum_exp)
|
||
{
|
||
/* First see if this is a symbol name. */
|
||
i = strtosigno (signum_exp);
|
||
if (i == 0)
|
||
{
|
||
/* Nope, maybe it's an address which evaluates to a signal
|
||
number. */
|
||
i = parse_and_eval_address (signum_exp);
|
||
if (i >= NSIG || i < 0)
|
||
error ("Signal number out of bounds.");
|
||
}
|
||
sig_print_info (i);
|
||
return;
|
||
}
|
||
|
||
printf_filtered ("\n");
|
||
for (i = 0; i < NSIG; i++)
|
||
{
|
||
QUIT;
|
||
|
||
sig_print_info (i);
|
||
}
|
||
|
||
printf_filtered ("\nUse the \"handle\" command to change these tables.\n");
|
||
}
|
||
|
||
/* 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). */
|
||
|
||
void
|
||
save_inferior_status (inf_status, restore_stack_info)
|
||
struct inferior_status *inf_status;
|
||
int restore_stack_info;
|
||
{
|
||
inf_status->pc_changed = pc_changed;
|
||
inf_status->stop_signal = stop_signal;
|
||
inf_status->stop_pc = stop_pc;
|
||
inf_status->stop_frame_address = stop_frame_address;
|
||
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_address = step_frame_address;
|
||
inf_status->step_over_calls = step_over_calls;
|
||
inf_status->step_resume_break_address = step_resume_break_address;
|
||
inf_status->stop_after_trap = stop_after_trap;
|
||
inf_status->stop_soon_quietly = stop_soon_quietly;
|
||
/* 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_i_s 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;
|
||
|
||
bcopy (stop_registers, inf_status->stop_registers, REGISTER_BYTES);
|
||
|
||
record_selected_frame (&(inf_status->selected_frame_address),
|
||
&(inf_status->selected_level));
|
||
return;
|
||
}
|
||
|
||
void
|
||
restore_inferior_status (inf_status)
|
||
struct inferior_status *inf_status;
|
||
{
|
||
FRAME fid;
|
||
int level = inf_status->selected_level;
|
||
|
||
pc_changed = inf_status->pc_changed;
|
||
stop_signal = inf_status->stop_signal;
|
||
stop_pc = inf_status->stop_pc;
|
||
stop_frame_address = inf_status->stop_frame_address;
|
||
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_address = inf_status->step_frame_address;
|
||
step_over_calls = inf_status->step_over_calls;
|
||
step_resume_break_address = inf_status->step_resume_break_address;
|
||
stop_after_trap = inf_status->stop_after_trap;
|
||
stop_soon_quietly = inf_status->stop_soon_quietly;
|
||
bpstat_clear (&stop_bpstat);
|
||
stop_bpstat = inf_status->stop_bpstat;
|
||
breakpoint_proceeded = inf_status->breakpoint_proceeded;
|
||
proceed_to_finish = inf_status->proceed_to_finish;
|
||
|
||
bcopy (inf_status->stop_registers, stop_registers, REGISTER_BYTES);
|
||
|
||
/* The inferior can be gone if the user types "print exit(0)"
|
||
(and perhaps other times). */
|
||
if (target_has_stack && inf_status->restore_stack_info)
|
||
{
|
||
fid = find_relative_frame (get_current_frame (),
|
||
&level);
|
||
|
||
/* If inf_status->selected_frame_address is NULL, there was no
|
||
previously selected frame. */
|
||
if (fid == 0 ||
|
||
FRAME_FP (fid) != inf_status->selected_frame_address ||
|
||
level != 0)
|
||
{
|
||
#if 1
|
||
/* I'm not sure this error message is a good idea. I have
|
||
only seen it occur after "Can't continue previously
|
||
requested operation" (we get called from do_cleanups), in
|
||
which case it just adds insult to injury (one confusing
|
||
error message after another. Besides which, does the
|
||
user really care if we can't restore the previously
|
||
selected frame? */
|
||
fprintf (stderr, "Unable to restore previously selected frame.\n");
|
||
#endif
|
||
select_frame (get_current_frame (), 0);
|
||
return;
|
||
}
|
||
|
||
select_frame (fid, inf_status->selected_level);
|
||
}
|
||
}
|
||
|
||
|
||
void
|
||
_initialize_infrun ()
|
||
{
|
||
register int i;
|
||
register int numsigs;
|
||
|
||
add_info ("signals", signals_info,
|
||
"What debugger does when program gets various signals.\n\
|
||
Specify a signal number as argument to print info on that signal only.");
|
||
|
||
add_com ("handle", class_run, handle_command,
|
||
"Specify how to handle a signal.\n\
|
||
Args are signal number followed by flags.\n\
|
||
Flags allowed are \"stop\", \"print\", \"pass\",\n\
|
||
\"nostop\", \"noprint\" or \"nopass\".\n\
|
||
Print means print a message if this signal happens.\n\
|
||
Stop means reenter debugger if this signal happens (implies print).\n\
|
||
Pass means let program see this signal; otherwise program doesn't know.\n\
|
||
Pass and Stop may be combined.");
|
||
|
||
numsigs = signo_max () + 1;
|
||
signal_stop = xmalloc (sizeof (signal_stop[0]) * numsigs);
|
||
signal_print = xmalloc (sizeof (signal_print[0]) * numsigs);
|
||
signal_program = 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[SIGTRAP] = 0;
|
||
signal_program[SIGINT] = 0;
|
||
|
||
/* Signals that are not errors should not normally enter the debugger. */
|
||
#ifdef SIGALRM
|
||
signal_stop[SIGALRM] = 0;
|
||
signal_print[SIGALRM] = 0;
|
||
#endif /* SIGALRM */
|
||
#ifdef SIGVTALRM
|
||
signal_stop[SIGVTALRM] = 0;
|
||
signal_print[SIGVTALRM] = 0;
|
||
#endif /* SIGVTALRM */
|
||
#ifdef SIGPROF
|
||
signal_stop[SIGPROF] = 0;
|
||
signal_print[SIGPROF] = 0;
|
||
#endif /* SIGPROF */
|
||
#ifdef SIGCHLD
|
||
signal_stop[SIGCHLD] = 0;
|
||
signal_print[SIGCHLD] = 0;
|
||
#endif /* SIGCHLD */
|
||
#ifdef SIGCLD
|
||
signal_stop[SIGCLD] = 0;
|
||
signal_print[SIGCLD] = 0;
|
||
#endif /* SIGCLD */
|
||
#ifdef SIGIO
|
||
signal_stop[SIGIO] = 0;
|
||
signal_print[SIGIO] = 0;
|
||
#endif /* SIGIO */
|
||
#ifdef SIGURG
|
||
signal_stop[SIGURG] = 0;
|
||
signal_print[SIGURG] = 0;
|
||
#endif /* SIGURG */
|
||
}
|