binutils-gdb/gdb/go32-nat.c

900 lines
19 KiB
C

/* Native debugging support for Intel x86 running DJGPP.
Copyright 1997, 1999 Free Software Foundation, Inc.
Written by Robert Hoehne.
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. */
#include <fcntl.h>
#include "defs.h"
#include "frame.h" /* required by inferior.h */
#include "inferior.h"
#include "target.h"
#include "wait.h"
#include "gdbcore.h"
#include "command.h"
#include "floatformat.h"
#include <stdio.h> /* required for __DJGPP_MINOR__ */
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <debug/v2load.h>
#include <debug/dbgcom.h>
#if __DJGPP_MINOR__ < 3
/* This code will be provided from DJGPP 2.03 on. Until then I code it
here */
typedef struct {
unsigned short sig0;
unsigned short sig1;
unsigned short sig2;
unsigned short sig3;
unsigned short exponent:15;
unsigned short sign:1;
} NPXREG;
typedef struct {
unsigned int control;
unsigned int status;
unsigned int tag;
unsigned int eip;
unsigned int cs;
unsigned int dataptr;
unsigned int datasel;
NPXREG reg[8];
} NPX;
static NPX npx;
static void save_npx (void); /* Save the FPU of the debugged program */
static void load_npx (void); /* Restore the FPU of the debugged program */
/* ------------------------------------------------------------------------- */
/* Store the contents of the NPX in the global variable `npx'. */
static void
save_npx (void)
{
asm ("inb $0xa0, %%al
testb $0x20, %%al
jz 1f
xorb %%al, %%al
outb %%al, $0xf0
movb $0x20, %%al
outb %%al, $0xa0
outb %%al, $0x20
1:
fnsave %0
fwait"
: "=m" (npx)
: /* No input */
: "%eax");
}
/* ------------------------------------------------------------------------- */
/* Reload the contents of the NPX from the global variable `npx'. */
static void
load_npx (void)
{
asm ("frstor %0" : "=m" (npx));
}
#endif /* __DJGPP_MINOR < 3 */
extern void _initialize_go32_nat (void);
struct env387
{
unsigned short control;
unsigned short r0;
unsigned short status;
unsigned short r1;
unsigned short tag;
unsigned short r2;
unsigned long eip;
unsigned short code_seg;
unsigned short opcode;
unsigned long operand;
unsigned short operand_seg;
unsigned short r3;
unsigned char regs[8][10];
};
extern char **environ;
#define SOME_PID 42
static int prog_has_started = 0;
static void
print_387_status (unsigned short status, struct env387 *ep);
static void
go32_open (char *name, int from_tty);
static void
go32_close (int quitting);
static void
go32_attach (char *args, int from_tty);
static void
go32_detach (char *args, int from_tty);
static void
go32_resume (int pid, int step, enum target_signal siggnal);
static int
go32_wait (int pid, struct target_waitstatus *status);
static void
go32_fetch_registers (int regno);
static void
store_register (int regno);
static void
go32_store_registers (int regno);
static void
go32_prepare_to_store (void);
static int
go32_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
struct target_ops *target);
static void
go32_files_info (struct target_ops *target);
static void
go32_stop (void);
static void
go32_kill_inferior (void);
static void
go32_create_inferior (char *exec_file, char *args, char **env);
static void
go32_mourn_inferior (void);
static int
go32_can_run (void);
static void
ignore (void);
static void
ignore2 (char *a, int b);
static int go32_insert_aligned_watchpoint (int pid, CORE_ADDR waddr,
CORE_ADDR addr, int len, int rw);
static int go32_insert_nonaligned_watchpoint (int pid, CORE_ADDR waddr,
CORE_ADDR addr, int len, int rw);
static struct target_ops go32_ops;
static void
go32_terminal_init (void);
static void
go32_terminal_inferior (void);
static void
go32_terminal_ours (void);
static void
print_387_status (unsigned short status, struct env387 *ep)
{
int i;
int bothstatus;
int top;
int fpreg;
bothstatus = ((status != 0) && (ep->status != 0));
if (status != 0)
{
if (bothstatus)
printf_unfiltered ("u: ");
print_387_status_word (status);
}
if (ep->status != 0)
{
if (bothstatus)
printf_unfiltered ("e: ");
print_387_status_word (ep->status);
}
print_387_control_word (ep->control & 0xffff);
printf_unfiltered ("last exception: ");
printf_unfiltered ("opcode %s; ", local_hex_string (ep->opcode));
printf_unfiltered ("pc %s:", local_hex_string (ep->code_seg));
printf_unfiltered ("%s; ", local_hex_string (ep->eip));
printf_unfiltered ("operand %s", local_hex_string (ep->operand_seg));
printf_unfiltered (":%s\n", local_hex_string (ep->operand));
top = (ep->status >> 11) & 7;
printf_unfiltered ("regno tag msb lsb value\n");
for (fpreg = 0; fpreg < 8; fpreg++)
{
long double val;
printf_unfiltered ("%s %d: ", fpreg == top ? "=>" : " ", fpreg);
switch ((ep->tag >> (fpreg * 2)) & 3)
{
case 0:
printf_unfiltered ("valid ");
break;
case 1:
printf_unfiltered ("zero ");
break;
case 2:
printf_unfiltered ("trap ");
break;
case 3:
printf_unfiltered ("empty ");
break;
}
for (i = 0; i < 8; i++)
printf_unfiltered ("%02x", ep->regs[fpreg][i]);
REGISTER_CONVERT_TO_VIRTUAL (FP0_REGNUM + fpreg, builtin_type_long_double,
&ep->regs[fpreg], &val);
printf_unfiltered (" %LG\n", val);
}
}
void
i386_go32_float_info (void)
{
print_387_status (0, (struct env387 *) &npx);
}
#define r_ofs(x) ((int)(&(((TSS *)0)->x)))
static struct
{
int tss_ofs;
int size;
}
regno_mapping[] =
{
r_ofs (tss_eax), 4,
r_ofs (tss_ecx), 4,
r_ofs (tss_edx), 4,
r_ofs (tss_ebx), 4,
r_ofs (tss_esp), 4,
r_ofs (tss_ebp), 4,
r_ofs (tss_esi), 4,
r_ofs (tss_edi), 4,
r_ofs (tss_eip), 4,
r_ofs (tss_eflags), 4,
r_ofs (tss_cs), 2,
r_ofs (tss_ss), 2,
r_ofs (tss_ds), 2,
r_ofs (tss_es), 2,
r_ofs (tss_fs), 2,
r_ofs (tss_gs), 2,
0, 10,
1, 10,
2, 10,
3, 10,
4, 10,
5, 10,
6, 10,
7, 10,
0, 2,
4, 2,
8, 2,
12, 4,
16, 2,
20, 4,
24, 2
};
static struct
{
int go32_sig;
int gdb_sig;
}
sig_map[] =
{
0, TARGET_SIGNAL_FPE,
1, TARGET_SIGNAL_TRAP,
2, TARGET_SIGNAL_UNKNOWN,
3, TARGET_SIGNAL_TRAP,
4, TARGET_SIGNAL_FPE,
5, TARGET_SIGNAL_SEGV,
6, TARGET_SIGNAL_ILL,
7, TARGET_SIGNAL_FPE,
8, TARGET_SIGNAL_SEGV,
9, TARGET_SIGNAL_SEGV,
10, TARGET_SIGNAL_BUS,
11, TARGET_SIGNAL_SEGV,
12, TARGET_SIGNAL_SEGV,
13, TARGET_SIGNAL_ABRT,
14, TARGET_SIGNAL_SEGV,
16, TARGET_SIGNAL_FPE,
31, TARGET_SIGNAL_ILL,
0x75, TARGET_SIGNAL_FPE,
0x79, TARGET_SIGNAL_INT,
0x1b, TARGET_SIGNAL_INT,
-1, -1
};
static void
go32_open (char *name, int from_tty)
{
printf_unfiltered ("Use the `run' command to run go32 programs\n");
}
static void
go32_close (int quitting)
{
}
static void
go32_attach (char *args, int from_tty)
{
printf_unfiltered ("Use the `run' command to run go32 programs\n");
}
static void
go32_detach (char *args, int from_tty)
{
}
static int resume_is_step;
static void
go32_resume (int pid, int step, enum target_signal siggnal)
{
resume_is_step = step;
}
static int
go32_wait (int pid, struct target_waitstatus *status)
{
int i;
if (resume_is_step)
a_tss.tss_eflags |= 0x0100;
else
a_tss.tss_eflags &= 0xfeff;
#if __DJGPP_MINOR__ < 3
save_npx ();
#endif
run_child ();
#if __DJGPP_MINOR__ < 3
load_npx ();
#endif
if (a_tss.tss_irqn == 0x21)
{
status->kind = TARGET_WAITKIND_EXITED;
status->value.integer = a_tss.tss_eax & 0xff;
}
else
{
status->value.sig = TARGET_SIGNAL_UNKNOWN;
status->kind = TARGET_WAITKIND_STOPPED;
for (i = 0; sig_map[i].go32_sig != -1; i++)
{
if (a_tss.tss_irqn == sig_map[i].go32_sig)
{
if ((status->value.sig = sig_map[i].gdb_sig) !=
TARGET_SIGNAL_TRAP)
status->kind = TARGET_WAITKIND_SIGNALLED;
break;
}
}
}
return SOME_PID;
}
static void
go32_fetch_registers (int regno)
{
/*JHW*/
int end_reg = regno + 1; /* just one reg initially */
if (regno < 0) /* do the all registers */
{
regno = 0; /* start at first register */
/* # regs in table */
end_reg = sizeof (regno_mapping) / sizeof (regno_mapping[0]);
}
for (; regno < end_reg; regno++)
{
if (regno < 16)
supply_register (regno,
(char *) &a_tss + regno_mapping[regno].tss_ofs);
else if (regno < 24)
supply_register (regno,
(char *) &npx.reg[regno_mapping[regno].tss_ofs]);
else if (regno < 31)
supply_register (regno,
(char *) &npx.reg + regno_mapping[regno].tss_ofs);
else
{
printf_unfiltered ("Invalid register in go32_fetch_register(%d)",
regno);
exit (1);
}
}
}
static void
store_register (int regno)
{
void *rp;
void *v = (void *) &registers[REGISTER_BYTE (regno)];
if (regno < 16)
rp = (char *) &a_tss + regno_mapping[regno].tss_ofs;
else if (regno < 24)
rp = (char *) &npx.reg[regno_mapping[regno].tss_ofs];
else if (regno > 31)
rp = (char *) &npx + regno_mapping[regno].tss_ofs;
else
{
printf_unfiltered ("Invalid register in store_register(%d)", regno);
exit (1);
}
memcpy (rp, v, regno_mapping[regno].size);
}
static void
go32_store_registers (int regno)
{
int r;
if (regno >= 0)
store_register (regno);
else
{
for (r = 0; r < sizeof (regno_mapping) / sizeof (regno_mapping[0]); r++)
store_register (r);
}
}
static void
go32_prepare_to_store (void)
{
}
static int
go32_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
struct target_ops *target)
{
if (write)
{
if (write_child (memaddr, myaddr, len))
{
return 0;
}
else
{
return len;
}
}
else
{
if (read_child (memaddr, myaddr, len))
{
return 0;
}
else
{
return len;
}
}
}
static void
go32_files_info (struct target_ops *target)
{
printf_unfiltered ("You are running a DJGPP V2 program\n");
}
static void
go32_stop (void)
{
normal_stop ();
cleanup_client ();
inferior_pid = 0;
prog_has_started = 0;
}
static void
go32_kill_inferior (void)
{
unpush_target (&go32_ops);
}
static void
go32_create_inferior (char *exec_file, char *args, char **env)
{
jmp_buf start_state;
char *cmdline;
char **env_save = environ;
if (prog_has_started)
{
go32_stop ();
go32_kill_inferior ();
}
cmdline = (char *) alloca (strlen (args) + 4);
cmdline[0] = strlen (args);
strcpy (cmdline + 1, args);
cmdline[strlen (args) + 1] = 13;
environ = env;
if (v2loadimage (exec_file, cmdline, start_state))
{
environ = env_save;
printf_unfiltered ("Load failed for image %s\n", exec_file);
exit (1);
}
environ = env_save;
edi_init (start_state);
inferior_pid = SOME_PID;
push_target (&go32_ops);
clear_proceed_status ();
insert_breakpoints ();
proceed ((CORE_ADDR) - 1, TARGET_SIGNAL_0, 0);
prog_has_started = 1;
}
static void
go32_mourn_inferior (void)
{
go32_kill_inferior ();
generic_mourn_inferior ();
}
static int
go32_can_run (void)
{
return 1;
}
static void
ignore (void)
{
}
static void
ignore2 (char *a, int b)
{
}
/* Hardware watchpoint support. */
#define DR_STATUS 6
#define DR_CONTROL 7
#define DR_ENABLE_SIZE 2
#define DR_LOCAL_ENABLE_SHIFT 0
#define DR_GLOBAL_ENABLE_SHIFT 1
#define DR_LOCAL_SLOWDOWN 0x100
#define DR_GLOBAL_SLOWDOWN 0x200
#define DR_CONTROL_SHIFT 16
#define DR_CONTROL_SIZE 4
#define DR_RW_READ 0x3
#define DR_RW_WRITE 0x1
#define DR_CONTROL_MASK 0xf
#define DR_ENABLE_MASK 0x3
#define DR_LEN_1 0x0
#define DR_LEN_2 0x4
#define DR_LEN_4 0xc
#define D_REGS edi.dr
#define CONTROL D_REGS[DR_CONTROL]
#define STATUS D_REGS[DR_STATUS]
#define IS_REG_FREE(index) \
(!(CONTROL & (3 << (DR_ENABLE_SIZE * index))))
#define LOCAL_ENABLE_REG(index) \
(CONTROL |= (1 << (DR_LOCAL_ENABLE_SHIFT + DR_ENABLE_SIZE * index)))
#define GLOBAL_ENABLE_REG(index) \
(CONTROL |= (1 << (DR_GLOBAL_ENABLE_SHIFT + DR_ENABLE_SIZE * index)))
#define DISABLE_REG(index) \
(CONTROL &= ~(3 << (DR_ENABLE_SIZE * index)))
#define SET_LOCAL_EXACT() \
(CONTROL |= DR_LOCAL_SLOWDOWN)
#define SET_GLOBAL_EXACT() \
(CONTROL |= DR_GLOBAL_SLOWDOWN)
#define SET_BREAK(index,address) \
do {\
CONTROL &= ~(DR_CONTROL_MASK << (DR_CONTROL_SHIFT + DR_CONTROL_SIZE * index));\
D_REGS[index] = address;\
} while(0)
#define SET_WATCH(index,address,rw,len) \
do {\
SET_BREAK(index,address);\
CONTROL |= (len | rw) << (DR_CONTROL_SHIFT + DR_CONTROL_SIZE * index);\
} while (0)
#define WATCH_HIT(index) \
(\
(STATUS & (1 << index)) && \
(CONTROL & (DR_CONTROL_MASK << (DR_CONTROL_SHIFT + DR_CONTROL_SIZE * index)))\
)
#if 0 /* use debugging macro */
#define SHOW_DR(text) \
do { \
fprintf(stderr,"%08x %08x ",edi.dr[7],edi.dr[6]); \
fprintf(stderr,"%08x %08x ",edi.dr[0],edi.dr[1]); \
fprintf(stderr,"%08x %08x ",edi.dr[2],edi.dr[3]); \
fprintf(stderr,"(%s)\n",#text); \
} while (0)
#else
#define SHOW_DR(text) do {} while (0)
#endif
/* Insert a watchpoint. */
int
go32_insert_watchpoint (int pid, CORE_ADDR addr, int len, int rw)
{
int ret = go32_insert_aligned_watchpoint (pid, addr, addr, len, rw);
SHOW_DR (insert_watch);
return ret;
}
static int
go32_insert_aligned_watchpoint (int pid, CORE_ADDR waddr, CORE_ADDR addr,
int len, int rw)
{
int i;
int read_write_bits, len_bits;
/* Look for a free debug register. */
for (i = 0; i <= 3; i++)
{
if (IS_REG_FREE (i))
break;
}
/* No more debug registers! */
if (i > 3)
return -1;
read_write_bits = ((rw & 1) ? DR_RW_READ : 0) | ((rw & 2) ? DR_RW_WRITE : 0);
if (len == 1)
len_bits = DR_LEN_1;
else if (len == 2)
{
if (addr % 2)
return go32_insert_nonaligned_watchpoint (pid, waddr, addr, len, rw);
len_bits = DR_LEN_2;
}
else if (len == 4)
{
if (addr % 4)
return go32_insert_nonaligned_watchpoint (pid, waddr, addr, len, rw);
len_bits = DR_LEN_4;
}
else
return go32_insert_nonaligned_watchpoint (pid, waddr, addr, len, rw);
SET_WATCH (i, addr, read_write_bits, len_bits);
LOCAL_ENABLE_REG (i);
SET_LOCAL_EXACT ();
}
static int
go32_insert_nonaligned_watchpoint (int pid, CORE_ADDR waddr, CORE_ADDR addr,
int len, int rw)
{
int align;
int size;
int rv = 0;
static int size_try_array[16] =
{
1, 1, 1, 1, /* trying size one */
2, 1, 2, 1, /* trying size two */
2, 1, 2, 1, /* trying size three */
4, 1, 2, 1 /* trying size four */
};
while (len > 0)
{
align = addr % 4;
/* Four is the maximum length for 386. */
size = (len > 4) ? 3 : len - 1;
size = size_try_array[size * 4 + align];
rv = go32_insert_aligned_watchpoint (pid, waddr, addr, size, rw);
if (rv)
{
go32_remove_watchpoint (pid, waddr, size);
return rv;
}
addr += size;
len -= size;
}
return rv;
}
/* Remove a watchpoint. */
int
go32_remove_watchpoint (int pid, CORE_ADDR addr, int len)
{
int i;
for (i = 0; i <= 3; i++)
{
if (D_REGS[i] == addr)
{
DISABLE_REG (i);
}
}
SHOW_DR (remove_watch);
return 0;
}
/* Check if stopped by a watchpoint. */
CORE_ADDR
go32_stopped_by_watchpoint (int pid)
{
int i, ret = 0;
int status;
status = edi.dr[DR_STATUS];
SHOW_DR (stopped_by);
for (i = 0; i <= 3; i++)
{
if (WATCH_HIT (i))
{
SHOW_DR (HIT);
ret = D_REGS[i];
}
}
/* this is a hack to GDB. If we stopped at a hardware breakpoint,
the stop_pc must incremented by DECR_PC_AFTER_BREAK. I tried everything
with the DECR_PC_AFTER_HW_BREAK, but nothing works. */
/* This is probably fixed by jtc's recent patch -sts 2/19/99 */
if (STATUS && !ret)
stop_pc += DECR_PC_AFTER_BREAK;
STATUS = 0;
return ret;
}
/* Remove a breakpoint. */
int
go32_remove_hw_breakpoint (CORE_ADDR addr, CORE_ADDR shadow)
{
int i;
for (i = 0; i <= 3; i++)
{
if (D_REGS[i] == addr)
{
DISABLE_REG (i);
}
}
SHOW_DR (remove_hw);
return 0;
}
int
go32_insert_hw_breakpoint (CORE_ADDR addr, CORE_ADDR shadow)
{
int i;
int read_write_bits, len_bits;
int free_debug_register;
int register_number;
/* Look for a free debug register. */
for (i = 0; i <= 3; i++)
{
if (IS_REG_FREE (i))
break;
}
/* No more debug registers! */
if (i > 3)
return -1;
SET_BREAK (i, addr);
LOCAL_ENABLE_REG (i);
SHOW_DR (insert_hw);
return 0;
}
static int inf_flags_valid = 0;
static int inf_in_flag;
static int inf_out_flag;
static void
go32_terminal_init (void)
{
/* Save the filemodes for stdin/stout */
inf_in_flag = setmode(0, 0);
setmode(0, inf_in_flag);
inf_out_flag = setmode(1, 0);
setmode(1, inf_out_flag);
inf_flags_valid = 1;
}
static void
go32_terminal_inferior (void)
{
/* set the filemodes for stdin/stdout of the inferior */
if (inf_flags_valid)
{
setmode(0, inf_in_flag);
setmode(1, inf_out_flag);
}
}
static void
go32_terminal_ours (void)
{
/* Switch to text mode on stdin/stdout always on the gdb terminal and
save the inferior modes to be restored later */
inf_in_flag = setmode(0, O_TEXT);
inf_out_flag = setmode(1, O_TEXT);
}
static void
init_go32_ops (void)
{
go32_ops.to_shortname = "djgpp";
go32_ops.to_longname = "djgpp target process";
go32_ops.to_doc =
"Program loaded by djgpp, when gdb is used as an external debugger";
go32_ops.to_open = go32_open;
go32_ops.to_close = go32_close;
go32_ops.to_detach = go32_detach;
go32_ops.to_resume = go32_resume;
go32_ops.to_wait = go32_wait;
go32_ops.to_fetch_registers = go32_fetch_registers;
go32_ops.to_store_registers = go32_store_registers;
go32_ops.to_prepare_to_store = go32_prepare_to_store;
go32_ops.to_xfer_memory = go32_xfer_memory;
go32_ops.to_files_info = go32_files_info;
go32_ops.to_insert_breakpoint = memory_insert_breakpoint;
go32_ops.to_remove_breakpoint = memory_remove_breakpoint;
go32_ops.to_terminal_init = go32_terminal_init;
go32_ops.to_terminal_inferior = go32_terminal_inferior;
go32_ops.to_terminal_ours_for_output = ignore;
go32_ops.to_terminal_ours = go32_terminal_ours;
go32_ops.to_terminal_info = ignore2;
go32_ops.to_kill = go32_kill_inferior;
go32_ops.to_create_inferior = go32_create_inferior;
go32_ops.to_mourn_inferior = go32_mourn_inferior;
go32_ops.to_can_run = go32_can_run;
go32_ops.to_stop = go32_stop;
go32_ops.to_stratum = process_stratum;
go32_ops.to_has_all_memory = 1;
go32_ops.to_has_memory = 1;
go32_ops.to_has_stack = 1;
go32_ops.to_has_registers = 1;
go32_ops.to_has_execution = 1;
go32_ops.to_magic = OPS_MAGIC;
}
void
_initialize_go32_nat (void)
{
init_go32_ops ();
add_target (&go32_ops);
}