/* Target-struct-independent code to start (run) and stop an inferior process.
- Copyright 1986, 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996
- Free Software Foundation, Inc.
+ Copyright 1986, 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
+ 1998 Free Software Foundation, Inc.
This file is part of GDB.
#include "gdbcore.h"
#include "gdbcmd.h"
#include "target.h"
-#include "thread.h"
+#include "gdbthread.h"
#include "annotate.h"
+#include "symfile.h" /* for overlay functions */
#include <signal.h>
-/* unistd.h is needed to #define X_OK */
-#ifdef USG
-#include <unistd.h>
-#else
-#include <sys/file.h>
-#endif
-
/* Prototypes for local functions */
static void signals_info PARAMS ((char *, int));
static int hook_stop_stub PARAMS ((char *));
+static void delete_breakpoint_current_contents PARAMS ((PTR));
+
/* GET_LONGJMP_TARGET returns the PC at which longjmp() will resume the
program. It needs to examine the jmp_buf argument and extract the PC
from it. The return value is non-zero on success, zero otherwise. */
#define DYNAMIC_TRAMPOLINE_NEXTPC(pc) 0
#endif
+/* On SVR4 based systems, determining the callee's address is exceedingly
+ difficult and depends on the implementation of the run time loader.
+ If we are stepping at the source level, we single step until we exit
+ the run time loader code and reach the callee's address. */
+
+#ifndef IN_SOLIB_DYNSYM_RESOLVE_CODE
+#define IN_SOLIB_DYNSYM_RESOLVE_CODE(pc) 0
+#endif
+
/* For SVR4 shared libraries, each call goes through a small piece of
trampoline code in the ".plt" section. IN_SOLIB_CALL_TRAMPOLINE evaluates
to nonzero if we are current stopped in one of these. */
#define IN_SOLIB_RETURN_TRAMPOLINE(pc,name) 0
#endif
+/* On MIPS16, a function that returns a floating point value may call
+ a library helper function to copy the return value to a floating point
+ register. The IGNORE_HELPER_CALL macro returns non-zero if we
+ should ignore (i.e. step over) this function call. */
+#ifndef IGNORE_HELPER_CALL
+#define IGNORE_HELPER_CALL(pc) 0
+#endif
+
/* On some systems, the PC may be left pointing at an instruction that won't
actually be executed. This is usually indicated by a bit in the PSW. If
we find ourselves in such a state, then we step the target beyond the
static int trap_expected;
+#ifdef SOLIB_ADD
/* Nonzero if we want to give control to the user when we're notified
of shared library events by the dynamic linker. */
static int stop_on_solib_events;
+#endif
#ifdef HP_OS_BUG
/* Nonzero if the next time we try to continue the inferior, it will
static int stop_print_frame;
-#ifdef NO_SINGLE_STEP
-extern int one_stepped; /* From machine dependent code */
-extern void single_step (); /* Same. */
-#endif /* NO_SINGLE_STEP */
-
\f
/* Things to clean up if we QUIT out of resume (). */
/* ARGSUSED */
step one instruction before inserting breakpoints
so that we do not stop right away. */
- if (breakpoint_here_p (read_pc ()))
+ if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
oneproc = 1;
#ifdef STEP_SKIPS_DELAY
struct cleanup *old_cleanups;
struct target_waitstatus w;
int another_trap;
- int random_signal;
+ int random_signal = 0;
CORE_ADDR stop_func_start;
CORE_ADDR stop_func_end;
char *stop_func_name;
- CORE_ADDR prologue_pc = 0, tmp;
+#if 0
+ CORE_ADDR prologue_pc = 0;
+#endif
+ CORE_ADDR tmp;
struct symtab_and_line sal;
int remove_breakpoints_on_following_step = 0;
int current_line;
while (1)
{
+ extern int overlay_cache_invalid; /* declared in symfile.h */
+
+ overlay_cache_invalid = 1;
+
/* We have to invalidate the registers BEFORE calling target_wait because
they can be loaded from the target while in target_wait. This makes
remote debugging a bit more efficient for those targets that provide
else
pid = target_wait (-1, &w);
-#ifdef HAVE_NONSTEPPABLE_WATCHPOINT
+ /* Gross.
+
+ We goto this label from elsewhere in wait_for_inferior when we want
+ to continue the main loop without calling "wait" and trashing the
+ waitstatus contained in W. */
have_waited:
-#endif
flush_cached_frames ();
/* If it's a new process, add it to the thread database */
- if (pid != inferior_pid
+ if (w.kind != TARGET_WAITKIND_EXITED
+ && pid != inferior_pid
&& !in_thread_list (pid))
{
- fprintf_unfiltered (gdb_stderr, "[New %s]\n", target_pid_to_str (pid));
add_thread (pid);
+ printf_filtered ("[New %s]\n", target_pid_to_str (pid));
/* We may want to consider not doing a resume here in order to give
the user a chance to play with the new thread. It might be good
switch (w.kind)
{
case TARGET_WAITKIND_LOADED:
- /* Ignore it gracefully. */
- if (breakpoints_inserted)
+ /* Ignore gracefully during startup of the inferior, as it
+ might be the shell which has just loaded some objects,
+ otherwise add the symbols for the newly loaded objects. */
+#ifdef SOLIB_ADD
+ if (!stop_soon_quietly)
{
- mark_breakpoints_out ();
- insert_breakpoints ();
+ extern int auto_solib_add;
+
+ /* Remove breakpoints, SOLIB_ADD might adjust
+ breakpoint addresses via breakpoint_re_set. */
+ if (breakpoints_inserted)
+ remove_breakpoints ();
+
+ /* Check for any newly added shared libraries if we're
+ supposed to be adding them automatically. */
+ if (auto_solib_add)
+ {
+ /* Switch terminal for any messages produced by
+ breakpoint_re_set. */
+ target_terminal_ours_for_output ();
+ SOLIB_ADD (NULL, 0, NULL);
+ target_terminal_inferior ();
+ }
+
+ /* Reinsert breakpoints and continue. */
+ if (breakpoints_inserted)
+ insert_breakpoints ();
}
+#endif
resume (0, TARGET_SIGNAL_0);
continue;
another thread. If so, then step that thread past the breakpoint,
and continue it. */
- if (stop_signal == TARGET_SIGNAL_TRAP
- && breakpoints_inserted
- && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK))
+ if (stop_signal == TARGET_SIGNAL_TRAP)
{
- random_signal = 0;
- if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK, pid))
- {
- /* Saw a breakpoint, but it was hit by the wrong thread. Just continue. */
- write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, pid);
+#ifdef NO_SINGLE_STEP
+ if (one_stepped)
+ random_signal = 0;
+ else
+#endif
+ if (breakpoints_inserted
+ && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK))
+ {
+ random_signal = 0;
+ if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK, pid))
+ {
+ /* Saw a breakpoint, but it was hit by the wrong thread. Just continue. */
+ write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, pid);
- remove_breakpoints ();
- target_resume (pid, 1, TARGET_SIGNAL_0); /* Single step */
- /* FIXME: What if a signal arrives instead of the single-step
- happening? */
+ remove_breakpoints ();
+ target_resume (pid, 1, TARGET_SIGNAL_0); /* Single step */
+ /* FIXME: What if a signal arrives instead of the single-step
+ happening? */
- if (target_wait_hook)
- target_wait_hook (pid, &w);
- else
- target_wait (pid, &w);
- insert_breakpoints ();
+ if (target_wait_hook)
+ target_wait_hook (pid, &w);
+ else
+ target_wait (pid, &w);
+ insert_breakpoints ();
- /* We need to restart all the threads now. */
- target_resume (-1, 0, TARGET_SIGNAL_0);
- continue;
- }
+ /* We need to restart all the threads now. */
+ target_resume (-1, 0, TARGET_SIGNAL_0);
+ continue;
+ }
+ }
}
else
random_signal = 1;
&step_frame_address, &handling_longjmp,
&another_trap);
printf_filtered ("[Switching to %s]\n", target_pid_to_str (pid));
-
flush_cached_frames ();
}
if (INSTRUCTION_NULLIFIED)
{
- resume (1, 0);
- continue;
+ struct target_waitstatus tmpstatus;
+
+ registers_changed ();
+ target_resume (pid, 1, TARGET_SIGNAL_0);
+
+ /* We may have received a signal that we want to pass to
+ the inferior; therefore, we must not clobber the waitstatus
+ in W. So we call wait ourselves, then continue the loop
+ at the "have_waited" label. */
+ if (target_wait_hook)
+ target_wait_hook (pid, &tmpstatus);
+ else
+ target_wait (pid, &tmpstatus);
+
+
+ goto have_waited;
}
#ifdef HAVE_STEPPABLE_WATCHPOINT
write_pc (stop_pc - DECR_PC_AFTER_BREAK);
remove_breakpoints ();
+ registers_changed();
target_resume (pid, 1, TARGET_SIGNAL_0); /* Single step */
if (target_wait_hook)
#endif
stop_func_start = 0;
+ stop_func_end = 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. */
/* See if there is a breakpoint at the current PC. */
stop_bpstat = bpstat_stop_status
(&stop_pc,
-#if DECR_PC_AFTER_BREAK
+ (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. */
- (prev_pc != stop_pc - DECR_PC_AFTER_BREAK
- && CURRENTLY_STEPPING ())
-#else /* DECR_PC_AFTER_BREAK zero */
- 0
-#endif /* DECR_PC_AFTER_BREAK zero */
+ the address of the breakpoint before the current pc
+ and 3) we didn't hit a breakpoint in a signal handler
+ without an intervening stop in sigtramp, which is
+ detected by a new stack pointer value below
+ any usual function calling stack adjustments. */
+ (CURRENTLY_STEPPING ()
+ && prev_pc != stop_pc - DECR_PC_AFTER_BREAK
+ && !(step_range_end
+ && read_sp () INNER_THAN (step_sp - 16))) :
+ 0)
);
/* Following in case break condition called a
function. */
another_trap = 1;
break;
-#ifdef SOLIB_ADD
case BPSTAT_WHAT_CHECK_SHLIBS:
+#ifdef SOLIB_ADD
{
extern int auto_solib_add;
breakpoint_re_set. */
target_terminal_ours_for_output ();
SOLIB_ADD (NULL, 0, NULL);
- re_enable_breakpoints_in_shlibs ();
target_terminal_inferior ();
}
+ /* Try to reenable shared library breakpoints, additional
+ code segments in shared libraries might be mapped in now. */
+ re_enable_breakpoints_in_shlibs ();
+
/* If requested, stop when the dynamic linker notifies
gdb of events. This allows the user to get control
and place breakpoints in initializer routines for
}
}
#endif
+ break;
case BPSTAT_WHAT_LAST:
/* Not a real code, but listed here to shut up gcc -Wall. */
/* We stepped out of the stepping range. */
+ /* If we are stepping at the source level and entered the runtime
+ loader dynamic symbol resolution code, we keep on single stepping
+ until we exit the run time loader code and reach the callee's
+ address. */
+ if (step_over_calls < 0 && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc))
+ goto keep_going;
+
/* We can't update step_sp every time through the loop, because
reading the stack pointer would slow down stepping too much.
But we can update it every time we leave the step range. */
/* Did we just take a signal? */
if (IN_SIGTRAMP (stop_pc, stop_func_name)
- && !IN_SIGTRAMP (prev_pc, prev_func_name))
+ && !IN_SIGTRAMP (prev_pc, prev_func_name)
+ && read_sp () INNER_THAN step_sp)
{
/* We've just taken a signal; go until we are back to
the point where we took it and one more. */
{
struct symtab_and_line sr_sal;
- sr_sal.pc = prev_pc;
- sr_sal.symtab = NULL;
- sr_sal.line = 0;
+ INIT_SAL (&sr_sal); /* initialize to zeroes */
+ sr_sal.pc = prev_pc;
+ sr_sal.section = find_pc_overlay (sr_sal.pc);
/* We could probably be setting the frame to
step_frame_address; I don't think anyone thought to try it. */
step_resume_breakpoint =
SKIP_PROLOGUE (prologue_pc);
}
- if ((/* Might be a non-recursive call. If the symbols are missing
- enough that stop_func_start == prev_func_start even though
- they are really two functions, we will treat some calls as
- jumps. */
- stop_func_start != prev_func_start
-
- /* Might be a recursive call if either we have a prologue
- or the call instruction itself saves the PC on the stack. */
- || prologue_pc != stop_func_start
- || read_sp () != step_sp)
+ if (!(step_sp INNER_THAN read_sp ()) /* don't mistake (sig)return as a call */
+ && (/* Might be a non-recursive call. If the symbols are missing
+ enough that stop_func_start == prev_func_start even though
+ they are really two functions, we will treat some calls as
+ jumps. */
+ stop_func_start != prev_func_start
+
+ /* Might be a recursive call if either we have a prologue
+ or the call instruction itself saves the PC on the stack. */
+ || prologue_pc != stop_func_start
+ || read_sp () != step_sp)
&& (/* PC is completely out of bounds of any known objfiles. Treat
like a subroutine call. */
! stop_func_start
break;
}
- if (step_over_calls > 0)
+ if (step_over_calls > 0 || IGNORE_HELPER_CALL (stop_pc))
/* We're doing a "next". */
goto step_over_function;
if (tmp)
{
struct symtab_and_line xxx;
-
- xxx.pc = tmp;
- xxx.symtab = NULL;
- xxx.line = 0;
+ /* Why isn't this s_a_l called "sr_sal", like all of the
+ other s_a_l's where this code is duplicated? */
+ INIT_SAL (&xxx); /* initialize to zeroes */
+ xxx.pc = tmp;
+ xxx.section = find_pc_overlay (xxx.pc);
step_resume_breakpoint =
set_momentary_breakpoint (xxx, NULL, bp_step_resume);
insert_breakpoints ();
{
/* Set a special breakpoint after the return */
struct symtab_and_line sr_sal;
+
+ INIT_SAL (&sr_sal); /* initialize to zeroes */
sr_sal.pc =
- ADDR_BITS_REMOVE
- (SAVED_PC_AFTER_CALL (get_current_frame ()));
- sr_sal.symtab = NULL;
- sr_sal.line = 0;
+ ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ()));
+ sr_sal.section = find_pc_overlay (sr_sal.pc);
step_resume_breakpoint =
set_momentary_breakpoint (sr_sal, get_current_frame (),
bp_step_resume);
- step_resume_breakpoint->frame = step_frame_address;
+ if (!IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
+ step_resume_breakpoint->frame = step_frame_address;
if (breakpoints_inserted)
insert_breakpoints ();
}
{
struct symtab_and_line sr_sal;
- sr_sal.pc = stop_func_start;
- sr_sal.symtab = NULL;
- sr_sal.line = 0;
+ INIT_SAL (&sr_sal); /* initialize to zeroes */
+ sr_sal.pc = stop_func_start;
+ sr_sal.section = find_pc_overlay (stop_func_start);
/* Do not specify what the fp should be when we stop
since on some machines the prologue
is where the new fp value is established. */
/* And put the step-breakpoint there and go until there. */
struct symtab_and_line sr_sal;
- sr_sal.pc = tmp;
- sr_sal.symtab = NULL;
- sr_sal.line = 0;
+ INIT_SAL (&sr_sal); /* initialize to zeroes */
+ sr_sal.pc = tmp;
+ sr_sal.section = find_pc_overlay (sr_sal.pc);
/* Do not specify what the fp should be when we stop
since on some machines the prologue
is where the new fp value is established. */
}
step_range_start = sal.pc;
step_range_end = sal.end;
+ step_frame_address = FRAME_FP (get_current_frame ());
+ current_line = sal.line;
+ current_symtab = sal.symtab;
goto keep_going;
check_sigtramp2:
if (trap_expected
&& IN_SIGTRAMP (stop_pc, stop_func_name)
- && !IN_SIGTRAMP (prev_pc, prev_func_name))
+ && !IN_SIGTRAMP (prev_pc, prev_func_name)
+ && read_sp () INNER_THAN step_sp)
{
/* What has happened here is that we have just stepped the inferior
with a signal (because it is a signal which shouldn't make
it says "exceedingly difficult"). */
struct symtab_and_line sr_sal;
- sr_sal.pc = prev_pc;
- sr_sal.symtab = NULL;
- sr_sal.line = 0;
+ INIT_SAL (&sr_sal); /* initialize to zeroes */
+ sr_sal.pc = prev_pc;
+ sr_sal.section = find_pc_overlay (sr_sal.pc);
/* We perhaps could set the frame if we kept track of what
the frame corresponding to prev_pc was. But we don't,
so don't. */
enum target_signal oursig;
{
char *name = target_signal_to_name (oursig);
+ int name_padding = 13 - strlen (name);
+ if (name_padding <= 0)
+ name_padding = 0;
+
printf_filtered ("%s", name);
- printf_filtered ("%*.*s ", 13 - strlen (name), 13 - strlen (name),
- " ");
+ printf_filtered ("%*.*s ", name_padding, name_padding, " ");
printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");