-/* Start and stop the inferior process, for GDB.
- Copyright (C) 1986, 1987, 1988, 1989 Free Software Foundation, Inc.
+/* Target-struct-independent code to start (run) and stop an inferior process.
+ Copyright 1986-1989, 1991-2000 Free Software Foundation, Inc.
-This file is part of GDB.
+ This file is part of GDB.
-GDB 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 1, or (at your option)
-any later version.
+ 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.
-GDB 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.
+ 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 GDB; see the file COPYING. If not, write to
-the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+ 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. */
-/* Notes on the algorithm used in wait_for_inferior to determine if we
- just did a subroutine call when stepping. We have the following
- information at that point:
+#include "defs.h"
+#include "gdb_string.h"
+#include <ctype.h>
+#include "symtab.h"
+#include "frame.h"
+#include "inferior.h"
+#include "breakpoint.h"
+#include "gdb_wait.h"
+#include "gdbcore.h"
+#include "gdbcmd.h"
+#include "target.h"
+#include "gdbthread.h"
+#include "annotate.h"
+#include "symfile.h" /* for overlay functions */
+#include "top.h"
+#include <signal.h>
+#include "inf-loop.h"
- Current and previous (just before this step) pc.
- Current and previous sp.
- Current and previous start of current function.
+/* Prototypes for local functions */
- If the start's of the functions don't match, then
+static void signals_info (char *, int);
- a) We did a subroutine call.
+static void handle_command (char *, int);
- In this case, the pc will be at the beginning of a function.
+static void sig_print_info (enum target_signal);
- b) We did a subroutine return.
+static void sig_print_header (void);
- Otherwise.
+static void resume_cleanups (int);
- c) We did a longjmp.
+static int hook_stop_stub (void *);
- If we did a longjump, we were doing "nexti", since a next would
- have attempted to skip over the assembly language routine in which
- the longjmp is coded and would have simply been the equivalent of a
- continue. I consider this ok behaivior. We'd like one of two
- things to happen if we are doing a nexti through the longjmp()
- routine: 1) It behaves as a stepi, or 2) It acts like a continue as
- above. Given that this is a special case, and that anybody who
- thinks that the concept of sub calls is meaningful in the context
- of a longjmp, I'll take either one. Let's see what happens.
+static void delete_breakpoint_current_contents (void *);
- Acts like a subroutine return. I can handle that with no problem
- at all.
+static void set_follow_fork_mode_command (char *arg, int from_tty,
+ struct cmd_list_element * c);
- -->So: If the current and previous beginnings of the current
- function don't match, *and* the pc is at the start of a function,
- we've done a subroutine call. If the pc is not at the start of a
- function, we *didn't* do a subroutine call.
+static struct inferior_status *xmalloc_inferior_status (void);
- -->If the beginnings of the current and previous function do match,
- either:
+static void free_inferior_status (struct inferior_status *);
- a) We just did a recursive call.
+static int restore_selected_frame (void *);
- In this case, we would be at the very beginning of a
- function and 1) it will have a prologue (don't jump to
- before prologue, or 2) (we assume here that it doesn't have
- a prologue) there will have been a change in the stack
- pointer over the last instruction. (Ie. it's got to put
- the saved pc somewhere. The stack is the usual place. In
- a recursive call a register is only an option if there's a
- prologue to do something with it. This is even true on
- register window machines; the prologue sets up the new
- window. It might not be true on a register window machine
- where the call instruction moved the register window
- itself. Hmmm. One would hope that the stack pointer would
- also change. If it doesn't, somebody send me a note, and
- I'll work out a more general theory.
- randy@wheaties.ai.mit.edu). This is true (albeit slipperly
- so) on all machines I'm aware of:
+static void build_infrun (void);
- m68k: Call changes stack pointer. Regular jumps don't.
+static void follow_inferior_fork (int parent_pid, int child_pid,
+ int has_forked, int has_vforked);
- sparc: Recursive calls must have frames and therefor,
- prologues.
+static void follow_fork (int parent_pid, int child_pid);
- vax: All calls have frames and hence change the
- stack pointer.
+static void follow_vfork (int parent_pid, int child_pid);
- b) We did a return from a recursive call. I don't see that we
- have either the ability or the need to distinguish this
- from an ordinary jump. The stack frame will be printed
- when and if the frame pointer changes; if we are in a
- function without a frame pointer, it's the users own
- lookout.
+static void set_schedlock_func (char *args, int from_tty,
+ struct cmd_list_element * c);
- c) We did a jump within a function. We assume that this is
- true if we didn't do a recursive call.
+struct execution_control_state;
- d) We are in no-man's land ("I see no symbols here"). We
- don't worry about this; it will make calls look like simple
- jumps (and the stack frames will be printed when the frame
- pointer moves), which is a reasonably non-violent response.
+static int currently_stepping (struct execution_control_state *ecs);
-#if 0
- We skip this; it causes more problems than it's worth.
-#ifdef SUN4_COMPILER_FEATURE
- We do a special ifdef for the sun 4, forcing it to single step
- into calls which don't have prologues. This means that we can't
- nexti over leaf nodes, we can probably next over them (since they
- won't have debugging symbols, usually), and we can next out of
- functions returning structures (with a "call .stret4" at the end).
+static void xdb_handle_command (char *args, int from_tty);
+
+void _initialize_infrun (void);
+
+int inferior_ignoring_startup_exec_events = 0;
+int inferior_ignoring_leading_exec_events = 0;
+
+/* In asynchronous mode, but simulating synchronous execution. */
+
+int sync_execution = 0;
+
+/* wait_for_inferior and normal_stop use this to notify the user
+ when the inferior stopped in a different thread than it had been
+ running in. */
+
+static int previous_inferior_pid;
+
+/* This is true for configurations that may follow through execl() and
+ similar functions. At present this is only true for HP-UX native. */
+
+#ifndef MAY_FOLLOW_EXEC
+#define MAY_FOLLOW_EXEC (0)
#endif
+
+static int may_follow_exec = MAY_FOLLOW_EXEC;
+
+/* resume and wait_for_inferior use this to ensure that when
+ stepping over a hit breakpoint in a threaded application
+ only the thread that hit the breakpoint is stepped and the
+ other threads don't continue. This prevents having another
+ thread run past the breakpoint while it is temporarily
+ removed.
+
+ This is not thread-specific, so it isn't saved as part of
+ the infrun state.
+
+ Versions of gdb which don't use the "step == this thread steps
+ and others continue" model but instead use the "step == this
+ thread steps and others wait" shouldn't do this. */
+
+static int thread_step_needed = 0;
+
+/* This is true if thread_step_needed should actually be used. At
+ present this is only true for HP-UX native. */
+
+#ifndef USE_THREAD_STEP_NEEDED
+#define USE_THREAD_STEP_NEEDED (0)
#endif
-*/
-
-
-
+static int use_thread_step_needed = USE_THREAD_STEP_NEEDED;
-#include <stdio.h>
-#include "defs.h"
-#include "param.h"
-#include "symtab.h"
-#include "frame.h"
-#include "inferior.h"
-#include "wait.h"
+/* 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. */
-#include <signal.h>
+#ifndef GET_LONGJMP_TARGET
+#define GET_LONGJMP_TARGET(PC_ADDR) 0
+#endif
-/* unistd.h is needed to #define X_OK */
-#ifdef USG
-#include <unistd.h>
-#else
-#include <sys/file.h>
+
+/* Some machines have trampoline code that sits between function callers
+ and the actual functions themselves. If this machine doesn't have
+ such things, disable their processing. */
+
+#ifndef SKIP_TRAMPOLINE_CODE
+#define SKIP_TRAMPOLINE_CODE(pc) 0
#endif
-#ifdef UMAX_PTRACE
-#include <aouthdr.h>
-#include <sys/param.h>
-#include <sys/ptrace.h>
-#endif /* UMAX_PTRACE */
-
-/* Required by <sys/user.h>. */
-#include <sys/types.h>
-/* Required by <sys/user.h>, at least on system V. */
-#include <sys/dir.h>
-/* Needed by IN_SIGTRAMP on some machines (e.g. vax). */
-#include <sys/param.h>
-/* Needed by IN_SIGTRAMP on some machines (e.g. vax). */
-#include <sys/user.h>
-
-extern char *sys_siglist[];
-extern int errno;
-
-/* Sigtramp is a routine that the kernel calls (which then calls the
- signal handler). On most machines it is a library routine that
- is linked into the executable.
-
- This macro, given a program counter value and the name of the
- function in which that PC resides (which can be null if the
- name is not known), returns nonzero if the PC and name show
- that we are in sigtramp.
-
- On most machines just see if the name is sigtramp (and if we have
- no name, assume we are not in sigtramp). */
-#if !defined (IN_SIGTRAMP)
-#define IN_SIGTRAMP(pc, name) \
- name && !strcmp ("_sigtramp", name)
+/* Dynamic function trampolines are similar to solib trampolines in that they
+ are between the caller and the callee. The difference is that when you
+ enter a dynamic trampoline, you can't determine the callee's address. Some
+ (usually complex) code needs to run in the dynamic trampoline to figure out
+ the callee's address. This macro is usually called twice. First, when we
+ enter the trampoline (looks like a normal function call at that point). It
+ should return the PC of a point within the trampoline where the callee's
+ address is known. Second, when we hit the breakpoint, this routine returns
+ the callee's address. At that point, things proceed as per a step resume
+ breakpoint. */
+
+#ifndef DYNAMIC_TRAMPOLINE_NEXTPC
+#define DYNAMIC_TRAMPOLINE_NEXTPC(pc) 0
#endif
-/* Tables of how to react to signals; the user sets them. */
+/* If the program uses ELF-style shared libraries, then calls to
+ functions in shared libraries go through stubs, which live in a
+ table called the PLT (Procedure Linkage Table). The first time the
+ function is called, the stub sends control to the dynamic linker,
+ which looks up the function's real address, patches the stub so
+ that future calls will go directly to the function, and then passes
+ control to the function.
+
+ If we are stepping at the source level, we don't want to see any of
+ this --- we just want to skip over the stub and the dynamic linker.
+ The simple approach is to single-step until control leaves the
+ dynamic linker.
+
+ However, on some systems (e.g., Red Hat Linux 5.2) the dynamic
+ linker calls functions in the shared C library, so you can't tell
+ from the PC alone whether the dynamic linker is still running. In
+ this case, we use a step-resume breakpoint to get us past the
+ dynamic linker, as if we were using "next" to step over a function
+ call.
+
+ IN_SOLIB_DYNSYM_RESOLVE_CODE says whether we're in the dynamic
+ linker code or not. Normally, this means we single-step. However,
+ if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
+ address where we can place a step-resume breakpoint to get past the
+ linker's symbol resolution function.
+
+ IN_SOLIB_DYNSYM_RESOLVE_CODE can generally be implemented in a
+ pretty portable way, by comparing the PC against the address ranges
+ of the dynamic linker's sections.
+
+ SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
+ it depends on internal details of the dynamic linker. It's usually
+ not too hard to figure out where to put a breakpoint, but it
+ certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
+ sanity checking. If it can't figure things out, returning zero and
+ getting the (possibly confusing) stepping behavior is better than
+ signalling an error, which will obscure the change in the
+ inferior's state. */
+
+#ifndef IN_SOLIB_DYNSYM_RESOLVE_CODE
+#define IN_SOLIB_DYNSYM_RESOLVE_CODE(pc) 0
+#endif
-static char signal_stop[NSIG];
-static char signal_print[NSIG];
-static char signal_program[NSIG];
+#ifndef SKIP_SOLIB_RESOLVER
+#define SKIP_SOLIB_RESOLVER(pc) 0
+#endif
-/* Nonzero if breakpoints are now inserted in the inferior. */
+/* 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. */
-static int breakpoints_inserted;
+#ifndef IN_SOLIB_CALL_TRAMPOLINE
+#define IN_SOLIB_CALL_TRAMPOLINE(pc,name) 0
+#endif
-/* Function inferior was in as of last step command. */
+/* In some shared library schemes, the return path from a shared library
+ call may need to go through a trampoline too. */
-static struct symbol *step_start_function;
+#ifndef IN_SOLIB_RETURN_TRAMPOLINE
+#define IN_SOLIB_RETURN_TRAMPOLINE(pc,name) 0
+#endif
+
+/* This function returns TRUE if pc is the address of an instruction
+ that lies within the dynamic linker (such as the event hook, or the
+ dld itself).
+
+ This function must be used only when a dynamic linker event has
+ been caught, and the inferior is being stepped out of the hook, or
+ undefined results are guaranteed. */
+
+#ifndef SOLIB_IN_DYNAMIC_LINKER
+#define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 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
+ nullified instruction before returning control to the user so as to avoid
+ confusion. */
+
+#ifndef INSTRUCTION_NULLIFIED
+#define INSTRUCTION_NULLIFIED 0
+#endif
+
+/* We can't step off a permanent breakpoint in the ordinary way, because we
+ can't remove it. Instead, we have to advance the PC to the next
+ instruction. This macro should expand to a pointer to a function that
+ does that, or zero if we have no such function. If we don't have a
+ definition for it, we have to report an error. */
+#ifndef SKIP_PERMANENT_BREAKPOINT
+#define SKIP_PERMANENT_BREAKPOINT (default_skip_permanent_breakpoint)
+static void
+default_skip_permanent_breakpoint (void)
+{
+ error_begin ();
+ fprintf_filtered (gdb_stderr, "\
+The program is stopped at a permanent breakpoint, but GDB does not know\n\
+how to step past a permanent breakpoint on this architecture. Try using\n\
+a command like `return' or `jump' to continue execution.\n");
+ return_to_top_level (RETURN_ERROR);
+}
+#endif
+
+
+/* Convert the #defines into values. This is temporary until wfi control
+ flow is completely sorted out. */
+
+#ifndef HAVE_STEPPABLE_WATCHPOINT
+#define HAVE_STEPPABLE_WATCHPOINT 0
+#else
+#undef HAVE_STEPPABLE_WATCHPOINT
+#define HAVE_STEPPABLE_WATCHPOINT 1
+#endif
+
+#ifndef HAVE_NONSTEPPABLE_WATCHPOINT
+#define HAVE_NONSTEPPABLE_WATCHPOINT 0
+#else
+#undef HAVE_NONSTEPPABLE_WATCHPOINT
+#define HAVE_NONSTEPPABLE_WATCHPOINT 1
+#endif
-/* This is the sequence of bytes we insert for a breakpoint. */
+#ifndef HAVE_CONTINUABLE_WATCHPOINT
+#define HAVE_CONTINUABLE_WATCHPOINT 0
+#else
+#undef HAVE_CONTINUABLE_WATCHPOINT
+#define HAVE_CONTINUABLE_WATCHPOINT 1
+#endif
+
+#ifndef CANNOT_STEP_HW_WATCHPOINTS
+#define CANNOT_STEP_HW_WATCHPOINTS 0
+#else
+#undef CANNOT_STEP_HW_WATCHPOINTS
+#define CANNOT_STEP_HW_WATCHPOINTS 1
+#endif
+
+/* Tables of how to react to signals; the user sets them. */
+
+static unsigned char *signal_stop;
+static unsigned char *signal_print;
+static unsigned char *signal_program;
-static char break_insn[] = BREAKPOINT;
+#define SET_SIGS(nsigs,sigs,flags) \
+ do { \
+ int signum = (nsigs); \
+ while (signum-- > 0) \
+ if ((sigs)[signum]) \
+ (flags)[signum] = 1; \
+ } while (0)
-/* Nonzero => address for special breakpoint for resuming stepping. */
+#define UNSET_SIGS(nsigs,sigs,flags) \
+ do { \
+ int signum = (nsigs); \
+ while (signum-- > 0) \
+ if ((sigs)[signum]) \
+ (flags)[signum] = 0; \
+ } while (0)
-static CORE_ADDR step_resume_break_address;
-/* Original contents of the byte where the special breakpoint is. */
+/* Command list pointer for the "stop" placeholder. */
-static char step_resume_break_shadow[sizeof break_insn];
+static struct cmd_list_element *stop_command;
-/* Nonzero means the special breakpoint is a duplicate
- so it has not itself been inserted. */
+/* Nonzero if breakpoints are now inserted in the inferior. */
+
+static int breakpoints_inserted;
+
+/* Function inferior was in as of last step command. */
-static int step_resume_break_duplicate;
+static struct symbol *step_start_function;
-/* Nonzero if we are expecting a trace trap and should proceed from it.
- 2 means expecting 2 trace traps and should continue both times.
- That occurs when we tell sh to exec the program: we will get
- a trap after the exec of sh and a second when the program is exec'd. */
+/* Nonzero if we are expecting a trace trap and should proceed from it. */
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
step one instruction and generate a spurious trace trap.
This is used to compensate for a bug in HP-UX. */
static int trap_expected_after_continue;
+#endif
/* Nonzero means expecting a trace trap
and should stop the inferior and return silently when it happens. */
int stop_after_trap;
-/* Nonzero means expecting a trace trap due to attaching to a process. */
-
-int stop_after_attach;
-
-/* Nonzero if pc has been changed by the debugger
- since the inferior stopped. */
+/* Nonzero means expecting a trap and caller will handle it themselves.
+ It is used after attach, due to attaching to a process;
+ when running in the shell before the child program has been exec'd;
+ and when running some kinds of remote stuff (FIXME?). */
-int pc_changed;
+int stop_soon_quietly;
-/* Nonzero if debugging a remote machine via a serial link or ethernet. */
+/* Nonzero if proceed is being used for a "finish" command or a similar
+ situation when stop_registers should be saved. */
-int remote_debugging;
+int proceed_to_finish;
-/* Save register contents here when about to pop a stack dummy frame. */
+/* Save register contents here when about to pop a stack dummy frame,
+ if-and-only-if proceed_to_finish is set.
+ Thus this contains the return value from the called function (assuming
+ values are returned in a register). */
-char stop_registers[REGISTER_BYTES];
+char *stop_registers;
/* Nonzero if program stopped due to error trying to insert breakpoints. */
static int breakpoints_failed;
-/* Nonzero if inferior is in sh before our program got exec'd. */
-
-static int running_in_shell;
-
/* Nonzero after stop if current stack frame should be printed. */
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 */
+static struct breakpoint *step_resume_breakpoint = NULL;
+static struct breakpoint *through_sigtramp_breakpoint = NULL;
+
+/* On some platforms (e.g., HP-UX), hardware watchpoints have bad
+ interactions with an inferior that is running a kernel function
+ (aka, a system call or "syscall"). wait_for_inferior therefore
+ may have a need to know when the inferior is in a syscall. This
+ is a count of the number of inferior threads which are known to
+ currently be running in a syscall. */
+static int number_of_threads_in_syscalls;
+
+/* This is used to remember when a fork, vfork or exec event
+ was caught by a catchpoint, and thus the event is to be
+ followed at the next resume of the inferior, and not
+ immediately. */
+static struct
+ {
+ enum target_waitkind kind;
+ struct
+ {
+ int parent_pid;
+ int saw_parent_fork;
+ int child_pid;
+ int saw_child_fork;
+ int saw_child_exec;
+ }
+ fork_event;
+ char *execd_pathname;
+ }
+pending_follow;
+
+/* Some platforms don't allow us to do anything meaningful with a
+ vforked child until it has exec'd. Vforked processes on such
+ platforms can only be followed after they've exec'd.
+
+ When this is set to 0, a vfork can be immediately followed,
+ and an exec can be followed merely as an exec. When this is
+ set to 1, a vfork event has been seen, but cannot be followed
+ until the exec is seen.
+
+ (In the latter case, inferior_pid is still the parent of the
+ vfork, and pending_follow.fork_event.child_pid is the child. The
+ appropriate process is followed, according to the setting of
+ follow-fork-mode.) */
+static int follow_vfork_when_exec;
+
+static char *follow_fork_mode_kind_names[] =
+{
+/* ??rehrauer: The "both" option is broken, by what may be a 10.20
+ kernel problem. It's also not terribly useful without a GUI to
+ help the user drive two debuggers. So for now, I'm disabling
+ the "both" option.
+ "parent", "child", "both", "ask" };
+ */
+ "parent", "child", "ask"};
+
+static char *follow_fork_mode_string = NULL;
+\f
+
+static void
+follow_inferior_fork (int parent_pid, int child_pid, int has_forked,
+ int has_vforked)
+{
+ int followed_parent = 0;
+ int followed_child = 0;
+
+ /* Which process did the user want us to follow? */
+ char *follow_mode =
+ savestring (follow_fork_mode_string, strlen (follow_fork_mode_string));
+
+ /* Or, did the user not know, and want us to ask? */
+ if (STREQ (follow_fork_mode_string, "ask"))
+ {
+ char requested_mode[100];
+
+ free (follow_mode);
+ error ("\"ask\" mode NYI");
+ follow_mode = savestring (requested_mode, strlen (requested_mode));
+ }
+
+ /* If we're to be following the parent, then detach from child_pid.
+ We're already following the parent, so need do nothing explicit
+ for it. */
+ if (STREQ (follow_mode, "parent"))
+ {
+ followed_parent = 1;
+
+ /* We're already attached to the parent, by default. */
+
+ /* Before detaching from the child, remove all breakpoints from
+ it. (This won't actually modify the breakpoint list, but will
+ physically remove the breakpoints from the child.) */
+ if (!has_vforked || !follow_vfork_when_exec)
+ {
+ detach_breakpoints (child_pid);
+#ifdef SOLIB_REMOVE_INFERIOR_HOOK
+ SOLIB_REMOVE_INFERIOR_HOOK (child_pid);
+#endif
+ }
+
+ /* Detach from the child. */
+ dont_repeat ();
+
+ target_require_detach (child_pid, "", 1);
+ }
+
+ /* If we're to be following the child, then attach to it, detach
+ from inferior_pid, and set inferior_pid to child_pid. */
+ else if (STREQ (follow_mode, "child"))
+ {
+ char child_pid_spelling[100]; /* Arbitrary length. */
+
+ followed_child = 1;
+
+ /* Before detaching from the parent, detach all breakpoints from
+ the child. But only if we're forking, or if we follow vforks
+ as soon as they happen. (If we're following vforks only when
+ the child has exec'd, then it's very wrong to try to write
+ back the "shadow contents" of inserted breakpoints now -- they
+ belong to the child's pre-exec'd a.out.) */
+ if (!has_vforked || !follow_vfork_when_exec)
+ {
+ detach_breakpoints (child_pid);
+ }
+
+ /* Before detaching from the parent, remove all breakpoints from it. */
+ remove_breakpoints ();
+
+ /* Also reset the solib inferior hook from the parent. */
+#ifdef SOLIB_REMOVE_INFERIOR_HOOK
+ SOLIB_REMOVE_INFERIOR_HOOK (inferior_pid);
+#endif
+
+ /* Detach from the parent. */
+ dont_repeat ();
+ target_detach (NULL, 1);
+
+ /* Attach to the child. */
+ inferior_pid = child_pid;
+ sprintf (child_pid_spelling, "%d", child_pid);
+ dont_repeat ();
+
+ target_require_attach (child_pid_spelling, 1);
+
+ /* Was there a step_resume breakpoint? (There was if the user
+ did a "next" at the fork() call.) If so, explicitly reset its
+ thread number.
+
+ step_resumes are a form of bp that are made to be per-thread.
+ Since we created the step_resume bp when the parent process
+ was being debugged, and now are switching to the child process,
+ from the breakpoint package's viewpoint, that's a switch of
+ "threads". We must update the bp's notion of which thread
+ it is for, or it'll be ignored when it triggers... */
+ if (step_resume_breakpoint &&
+ (!has_vforked || !follow_vfork_when_exec))
+ breakpoint_re_set_thread (step_resume_breakpoint);
+
+ /* Reinsert all breakpoints in the child. (The user may've set
+ breakpoints after catching the fork, in which case those
+ actually didn't get set in the child, but only in the parent.) */
+ if (!has_vforked || !follow_vfork_when_exec)
+ {
+ breakpoint_re_set ();
+ insert_breakpoints ();
+ }
+ }
+
+ /* If we're to be following both parent and child, then fork ourselves,
+ and attach the debugger clone to the child. */
+ else if (STREQ (follow_mode, "both"))
+ {
+ char pid_suffix[100]; /* Arbitrary length. */
+
+ /* Clone ourselves to follow the child. This is the end of our
+ involvement with child_pid; our clone will take it from here... */
+ dont_repeat ();
+ target_clone_and_follow_inferior (child_pid, &followed_child);
+ followed_parent = !followed_child;
+
+ /* We continue to follow the parent. To help distinguish the two
+ debuggers, though, both we and our clone will reset our prompts. */
+ sprintf (pid_suffix, "[%d] ", inferior_pid);
+ set_prompt (strcat (get_prompt (), pid_suffix));
+ }
+
+ /* The parent and child of a vfork share the same address space.
+ Also, on some targets the order in which vfork and exec events
+ are received for parent in child requires some delicate handling
+ of the events.
+
+ For instance, on ptrace-based HPUX we receive the child's vfork
+ event first, at which time the parent has been suspended by the
+ OS and is essentially untouchable until the child's exit or second
+ exec event arrives. At that time, the parent's vfork event is
+ delivered to us, and that's when we see and decide how to follow
+ the vfork. But to get to that point, we must continue the child
+ until it execs or exits. To do that smoothly, all breakpoints
+ must be removed from the child, in case there are any set between
+ the vfork() and exec() calls. But removing them from the child
+ also removes them from the parent, due to the shared-address-space
+ nature of a vfork'd parent and child. On HPUX, therefore, we must
+ take care to restore the bp's to the parent before we continue it.
+ Else, it's likely that we may not stop in the expected place. (The
+ worst scenario is when the user tries to step over a vfork() call;
+ the step-resume bp must be restored for the step to properly stop
+ in the parent after the call completes!)
+
+ Sequence of events, as reported to gdb from HPUX:
+
+ Parent Child Action for gdb to take
+ -------------------------------------------------------
+ 1 VFORK Continue child
+ 2 EXEC
+ 3 EXEC or EXIT
+ 4 VFORK */
+ if (has_vforked)
+ {
+ target_post_follow_vfork (parent_pid,
+ followed_parent,
+ child_pid,
+ followed_child);
+ }
+
+ pending_follow.fork_event.saw_parent_fork = 0;
+ pending_follow.fork_event.saw_child_fork = 0;
-static void insert_step_breakpoint ();
-static void remove_step_breakpoint ();
-static void wait_for_inferior ();
-static void normal_stop ();
+ free (follow_mode);
+}
+
+static void
+follow_fork (int parent_pid, int child_pid)
+{
+ follow_inferior_fork (parent_pid, child_pid, 1, 0);
+}
+
+
+/* Forward declaration. */
+static void follow_exec (int, char *);
+
+static void
+follow_vfork (int parent_pid, int child_pid)
+{
+ follow_inferior_fork (parent_pid, child_pid, 0, 1);
+
+ /* Did we follow the child? Had it exec'd before we saw the parent vfork? */
+ if (pending_follow.fork_event.saw_child_exec && (inferior_pid == child_pid))
+ {
+ pending_follow.fork_event.saw_child_exec = 0;
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+ follow_exec (inferior_pid, pending_follow.execd_pathname);
+ free (pending_follow.execd_pathname);
+ }
+}
+
+static void
+follow_exec (int pid, char *execd_pathname)
+{
+ int saved_pid = pid;
+ struct target_ops *tgt;
+
+ if (!may_follow_exec)
+ return;
+
+ /* Did this exec() follow a vfork()? If so, we must follow the
+ vfork now too. Do it before following the exec. */
+ if (follow_vfork_when_exec &&
+ (pending_follow.kind == TARGET_WAITKIND_VFORKED))
+ {
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+ follow_vfork (inferior_pid, pending_follow.fork_event.child_pid);
+ follow_vfork_when_exec = 0;
+ saved_pid = inferior_pid;
+
+ /* Did we follow the parent? If so, we're done. If we followed
+ the child then we must also follow its exec(). */
+ if (inferior_pid == pending_follow.fork_event.parent_pid)
+ return;
+ }
+
+ /* This is an exec event that we actually wish to pay attention to.
+ Refresh our symbol table to the newly exec'd program, remove any
+ momentary bp's, etc.
+
+ If there are breakpoints, they aren't really inserted now,
+ since the exec() transformed our inferior into a fresh set
+ of instructions.
+
+ We want to preserve symbolic breakpoints on the list, since
+ we have hopes that they can be reset after the new a.out's
+ symbol table is read.
+
+ However, any "raw" breakpoints must be removed from the list
+ (e.g., the solib bp's), since their address is probably invalid
+ now.
+
+ And, we DON'T want to call delete_breakpoints() here, since
+ that may write the bp's "shadow contents" (the instruction
+ value that was overwritten witha TRAP instruction). Since
+ we now have a new a.out, those shadow contents aren't valid. */
+ update_breakpoints_after_exec ();
+
+ /* If there was one, it's gone now. We cannot truly step-to-next
+ statement through an exec(). */
+ step_resume_breakpoint = NULL;
+ step_range_start = 0;
+ step_range_end = 0;
+
+ /* If there was one, it's gone now. */
+ through_sigtramp_breakpoint = NULL;
+
+ /* What is this a.out's name? */
+ printf_unfiltered ("Executing new program: %s\n", execd_pathname);
+
+ /* We've followed the inferior through an exec. Therefore, the
+ inferior has essentially been killed & reborn. */
+
+ /* First collect the run target in effect. */
+ tgt = find_run_target ();
+ /* If we can't find one, things are in a very strange state... */
+ if (tgt == NULL)
+ error ("Could find run target to save before following exec");
+
+ gdb_flush (gdb_stdout);
+ target_mourn_inferior ();
+ inferior_pid = saved_pid; /* Because mourn_inferior resets inferior_pid. */
+ push_target (tgt);
+
+ /* That a.out is now the one to use. */
+ exec_file_attach (execd_pathname, 0);
+
+ /* And also is where symbols can be found. */
+ symbol_file_command (execd_pathname, 0);
+
+ /* Reset the shared library package. This ensures that we get
+ a shlib event when the child reaches "_start", at which point
+ the dld will have had a chance to initialize the child. */
+#if defined(SOLIB_RESTART)
+ SOLIB_RESTART ();
+#endif
+#ifdef SOLIB_CREATE_INFERIOR_HOOK
+ SOLIB_CREATE_INFERIOR_HOOK (inferior_pid);
+#endif
+
+ /* Reinsert all breakpoints. (Those which were symbolic have
+ been reset to the proper address in the new a.out, thanks
+ to symbol_file_command...) */
+ insert_breakpoints ();
+
+ /* The next resume of this inferior should bring it to the shlib
+ startup breakpoints. (If the user had also set bp's on
+ "main" from the old (parent) process, then they'll auto-
+ matically get reset there in the new process.) */
+}
+
+/* Non-zero if we just simulating a single-step. This is needed
+ because we cannot remove the breakpoints in the inferior process
+ until after the `wait' in `wait_for_inferior'. */
+static int singlestep_breakpoints_inserted_p = 0;
+\f
+
+/* Things to clean up if we QUIT out of resume (). */
+/* ARGSUSED */
+static void
+resume_cleanups (int arg)
+{
+ normal_stop ();
+}
+
+static char schedlock_off[] = "off";
+static char schedlock_on[] = "on";
+static char schedlock_step[] = "step";
+static char *scheduler_mode = schedlock_off;
+static char *scheduler_enums[] =
+{schedlock_off, schedlock_on, schedlock_step};
+
+static void
+set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
+{
+ if (c->type == set_cmd)
+ if (!target_can_lock_scheduler)
+ {
+ scheduler_mode = schedlock_off;
+ error ("Target '%s' cannot support this command.",
+ target_shortname);
+ }
+}
+
+
+
+
+/* Resume the inferior, but allow a QUIT. This is useful if the user
+ wants to interrupt some lengthy single-stepping operation
+ (for child processes, the SIGINT goes to the inferior, and so
+ we get a SIGINT random_signal, but for remote debugging and perhaps
+ other targets, that's not true).
+
+ STEP nonzero if we should step (zero to continue instead).
+ SIG is the signal to give the inferior (zero for none). */
+void
+resume (int step, enum target_signal sig)
+{
+ int should_resume = 1;
+ struct cleanup *old_cleanups = make_cleanup ((make_cleanup_func)
+ resume_cleanups, 0);
+ QUIT;
+
+#ifdef CANNOT_STEP_BREAKPOINT
+ /* Most targets can step a breakpoint instruction, thus executing it
+ normally. But if this one cannot, just continue and we will hit
+ it anyway. */
+ if (step && breakpoints_inserted && breakpoint_here_p (read_pc ()))
+ step = 0;
+#endif
+
+ /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
+ over an instruction that causes a page fault without triggering
+ a hardware watchpoint. The kernel properly notices that it shouldn't
+ stop, because the hardware watchpoint is not triggered, but it forgets
+ the step request and continues the program normally.
+ Work around the problem by removing hardware watchpoints if a step is
+ requested, GDB will check for a hardware watchpoint trigger after the
+ step anyway. */
+ if (CANNOT_STEP_HW_WATCHPOINTS && step && breakpoints_inserted)
+ remove_hw_watchpoints ();
+
+
+ /* Normally, by the time we reach `resume', the breakpoints are either
+ removed or inserted, as appropriate. The exception is if we're sitting
+ at a permanent breakpoint; we need to step over it, but permanent
+ breakpoints can't be removed. So we have to test for it here. */
+ if (breakpoint_here_p (read_pc ()) == permanent_breakpoint_here)
+ SKIP_PERMANENT_BREAKPOINT ();
+
+ if (SOFTWARE_SINGLE_STEP_P && step)
+ {
+ /* Do it the hard way, w/temp breakpoints */
+ SOFTWARE_SINGLE_STEP (sig, 1 /*insert-breakpoints */ );
+ /* ...and don't ask hardware to do it. */
+ step = 0;
+ /* and do not pull these breakpoints until after a `wait' in
+ `wait_for_inferior' */
+ singlestep_breakpoints_inserted_p = 1;
+ }
+
+ /* Handle any optimized stores to the inferior NOW... */
+#ifdef DO_DEFERRED_STORES
+ DO_DEFERRED_STORES;
+#endif
+
+ /* If there were any forks/vforks/execs that were caught and are
+ now to be followed, then do so. */
+ switch (pending_follow.kind)
+ {
+ case (TARGET_WAITKIND_FORKED):
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+ follow_fork (inferior_pid, pending_follow.fork_event.child_pid);
+ break;
+
+ case (TARGET_WAITKIND_VFORKED):
+ {
+ int saw_child_exec = pending_follow.fork_event.saw_child_exec;
+
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+ follow_vfork (inferior_pid, pending_follow.fork_event.child_pid);
+
+ /* Did we follow the child, but not yet see the child's exec event?
+ If so, then it actually ought to be waiting for us; we respond to
+ parent vfork events. We don't actually want to resume the child
+ in this situation; we want to just get its exec event. */
+ if (!saw_child_exec &&
+ (inferior_pid == pending_follow.fork_event.child_pid))
+ should_resume = 0;
+ }
+ break;
+
+ case (TARGET_WAITKIND_EXECD):
+ /* If we saw a vfork event but couldn't follow it until we saw
+ an exec, then now might be the time! */
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+ /* follow_exec is called as soon as the exec event is seen. */
+ break;
+
+ default:
+ break;
+ }
+
+ /* Install inferior's terminal modes. */
+ target_terminal_inferior ();
+
+ if (should_resume)
+ {
+ int resume_pid;
+
+ if (use_thread_step_needed && thread_step_needed)
+ {
+ /* We stopped on a BPT instruction;
+ don't continue other threads and
+ just step this thread. */
+ thread_step_needed = 0;
+
+ if (!breakpoint_here_p (read_pc ()))
+ {
+ /* Breakpoint deleted: ok to do regular resume
+ where all the threads either step or continue. */
+ resume_pid = -1;
+ }
+ else
+ {
+ if (!step)
+ {
+ warning ("Internal error, changing continue to step.");
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
+ trap_expected = 1;
+ step = 1;
+ }
+ resume_pid = inferior_pid;
+ }
+ }
+ else
+ {
+ /* Vanilla resume. */
+ if ((scheduler_mode == schedlock_on) ||
+ (scheduler_mode == schedlock_step && step != 0))
+ resume_pid = inferior_pid;
+ else
+ resume_pid = -1;
+ }
+ target_resume (resume_pid, step, sig);
+ }
+ discard_cleanups (old_cleanups);
+}
\f
+
/* Clear out all variables saying what to do when inferior is continued.
First do this, then set the ones you want, then call `proceed'. */
void
-clear_proceed_status ()
+clear_proceed_status (void)
{
trap_expected = 0;
step_range_start = 0;
step_range_end = 0;
step_frame_address = 0;
step_over_calls = -1;
- step_resume_break_address = 0;
stop_after_trap = 0;
- stop_after_attach = 0;
+ stop_soon_quietly = 0;
+ proceed_to_finish = 0;
+ breakpoint_proceeded = 1; /* We're about to proceed... */
- /* Discard any remaining commands left by breakpoint we had stopped at. */
- clear_breakpoint_commands ();
+ /* Discard any remaining commands or status from previous stop. */
+ bpstat_clear (&stop_bpstat);
}
/* Basic routine for continuing the program in various fashions.
ADDR is the address to resume at, or -1 for resume where stopped.
- SIGNAL is the signal to give it, or 0 for none,
- or -1 for act according to how it stopped.
+ SIGGNAL is the signal to give it, or 0 for none,
+ or -1 for act according to how it stopped.
STEP is nonzero if should trap after one instruction.
- -1 means return after that and print nothing.
- You should probably set various step_... variables
- before calling here, if you are stepping.
+ -1 means return after that and print nothing.
+ You should probably set various step_... variables
+ before calling here, if you are stepping.
You should call clear_proceed_status before calling proceed. */
void
-proceed (addr, signal, step)
- CORE_ADDR addr;
- int signal;
- int step;
+proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
{
int oneproc = 0;
if (step < 0)
stop_after_trap = 1;
- if (addr == -1)
+ if (addr == (CORE_ADDR) -1)
{
/* If there is a breakpoint at the address we will resume at,
- step one instruction before inserting breakpoints
- so that we do not stop right away. */
+ step one instruction before inserting breakpoints
+ so that we do not stop right away (and report a second
+ hit at this breakpoint). */
- if (!pc_changed && breakpoint_here_p (read_pc ()))
+ if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
+ oneproc = 1;
+
+#ifndef STEP_SKIPS_DELAY
+#define STEP_SKIPS_DELAY(pc) (0)
+#define STEP_SKIPS_DELAY_P (0)
+#endif
+ /* Check breakpoint_here_p first, because breakpoint_here_p is fast
+ (it just checks internal GDB data structures) and STEP_SKIPS_DELAY
+ is slow (it needs to read memory from the target). */
+ if (STEP_SKIPS_DELAY_P
+ && breakpoint_here_p (read_pc () + 4)
+ && STEP_SKIPS_DELAY (read_pc ()))
oneproc = 1;
}
else
{
- write_register (PC_REGNUM, addr);
-#ifdef NPC_REGNUM
- write_register (NPC_REGNUM, addr + 4);
-#endif
+ write_pc (addr);
+
+ /* New address; we don't need to single-step a thread
+ over a breakpoint we just hit, 'cause we aren't
+ continuing from there.
+
+ It's not worth worrying about the case where a user
+ asks for a "jump" at the current PC--if they get the
+ hiccup of re-hiting a hit breakpoint, what else do
+ they expect? */
+ thread_step_needed = 0;
+ }
+
+#ifdef PREPARE_TO_PROCEED
+ /* In a multi-threaded task we may select another thread
+ and then continue or step.
+
+ But if the old thread was stopped at a breakpoint, it
+ will immediately cause another breakpoint stop without
+ any execution (i.e. it will report a breakpoint hit
+ incorrectly). So we must step over it first.
+
+ PREPARE_TO_PROCEED checks the current thread against the thread
+ that reported the most recent event. If a step-over is required
+ it returns TRUE and sets the current thread to the old thread. */
+ if (PREPARE_TO_PROCEED (1) && breakpoint_here_p (read_pc ()))
+ {
+ oneproc = 1;
+ thread_step_needed = 1;
}
+#endif /* PREPARE_TO_PROCEED */
+
+#ifdef HP_OS_BUG
if (trap_expected_after_continue)
{
/* If (step == 0), a trap will be automatically generated after
- the first instruction is executed. Force step one
- instruction to clear this condition. This should not occur
- if step is nonzero, but it is harmless in that case. */
+ the first instruction is executed. Force step one
+ instruction to clear this condition. This should not occur
+ if step is nonzero, but it is harmless in that case. */
oneproc = 1;
trap_expected_after_continue = 0;
}
+#endif /* HP_OS_BUG */
if (oneproc)
/* We will get a trace trap after one instruction.
error ("Cannot insert breakpoints.\n\
The same program may be running in another process.");
}
+
breakpoints_inserted = 1;
}
- /* Install inferior's terminal modes. */
- terminal_inferior ();
-
- if (signal >= 0)
- stop_signal = signal;
+ if (siggnal != TARGET_SIGNAL_DEFAULT)
+ stop_signal = siggnal;
/* If this signal should not be seen by program,
give it zero. Used for debugging signals. */
- else if (stop_signal < NSIG && !signal_program[stop_signal])
- stop_signal= 0;
+ else if (!signal_program[stop_signal])
+ stop_signal = TARGET_SIGNAL_0;
+
+ annotate_starting ();
+
+ /* Make sure that output from GDB appears before output from the
+ inferior. */
+ gdb_flush (gdb_stdout);
/* Resume inferior. */
- resume (oneproc || step, stop_signal);
+ resume (oneproc || step || bpstat_should_step (), stop_signal);
/* Wait for it to stop (if not standalone)
and in any case decode why it stopped, and act accordingly. */
-
- wait_for_inferior ();
- normal_stop ();
+ /* Do this only if we are not using the event loop, or if the target
+ does not support asynchronous execution. */
+ if (!event_loop_p || !target_can_async_p ())
+ {
+ wait_for_inferior ();
+ normal_stop ();
+ }
}
-/* Writing the inferior pc as a register calls this function
- to inform infrun that the pc has been set in the debugger. */
+/* Record the pc and sp of the program the last time it stopped.
+ These are just used internally by wait_for_inferior, but need
+ to be preserved over calls to it and cleared when the inferior
+ is started. */
+static CORE_ADDR prev_pc;
+static CORE_ADDR prev_func_start;
+static char *prev_func_name;
+\f
-void
-writing_pc (val)
- CORE_ADDR val;
+/* Start remote-debugging of a machine over a serial link. */
+
+void
+start_remote (void)
{
- stop_pc = val;
- pc_changed = 1;
+ init_thread_list ();
+ init_wait_for_inferior ();
+ stop_soon_quietly = 1;
+ trap_expected = 0;
+
+ /* Always go on waiting for the target, regardless of the mode. */
+ /* FIXME: cagney/1999-09-23: At present it isn't possible to
+ indicate th wait_for_inferior that a target should timeout if
+ nothing is returned (instead of just blocking). Because of this,
+ targets expecting an immediate response need to, internally, set
+ things up so that the target_wait() is forced to eventually
+ timeout. */
+ /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
+ differentiate to its caller what the state of the target is after
+ the initial open has been performed. Here we're assuming that
+ the target has stopped. It should be possible to eventually have
+ target_open() return to the caller an indication that the target
+ is currently running and GDB state should be set to the same as
+ for an async run. */
+ wait_for_inferior ();
+ normal_stop ();
}
-/* Start an inferior process for the first time.
- Actually it was started by the fork that created it,
- but it will have stopped one instruction after execing sh.
- Here we must get it up to actual execution of the real program. */
+/* Initialize static vars when a new inferior begins. */
void
-start_inferior ()
+init_wait_for_inferior (void)
{
- /* 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. */
+ /* These are meaningless until the first time through wait_for_inferior. */
+ prev_pc = 0;
+ prev_func_start = 0;
+ prev_func_name = NULL;
-#ifdef START_INFERIOR_TRAPS_EXPECTED
- trap_expected = START_INFERIOR_TRAPS_EXPECTED;
-#else
- trap_expected = 2;
-#endif
-
- running_in_shell = 0; /* Set to 1 at first SIGTRAP, 0 at second. */
+#ifdef HP_OS_BUG
trap_expected_after_continue = 0;
+#endif
breakpoints_inserted = 0;
- mark_breakpoints_out ();
+ breakpoint_init_inferior (inf_starting);
- /* Set up the "saved terminal modes" of the inferior
- based on what modes we are starting it with. */
- terminal_init_inferior ();
+ /* Don't confuse first call to proceed(). */
+ stop_signal = TARGET_SIGNAL_0;
- /* Install inferior's terminal modes. */
- terminal_inferior ();
+ /* The first resume is not following a fork/vfork/exec. */
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
+ pending_follow.fork_event.saw_parent_fork = 0;
+ pending_follow.fork_event.saw_child_fork = 0;
+ pending_follow.fork_event.saw_child_exec = 0;
+
+ /* See wait_for_inferior's handling of SYSCALL_ENTRY/RETURN events. */
+ number_of_threads_in_syscalls = 0;
- if (remote_debugging)
+ clear_proceed_status ();
+}
+
+static void
+delete_breakpoint_current_contents (void *arg)
+{
+ struct breakpoint **breakpointp = (struct breakpoint **) arg;
+ if (*breakpointp != NULL)
{
- trap_expected = 0;
- fetch_inferior_registers();
- set_current_frame (create_new_frame (read_register (FP_REGNUM),
- read_pc ()));
- stop_frame_address = FRAME_FP (get_current_frame());
- inferior_pid = 3;
- if (insert_breakpoints())
- fatal("Can't insert breakpoints");
- breakpoints_inserted = 1;
- proceed(-1, -1, 0);
+ delete_breakpoint (*breakpointp);
+ *breakpointp = NULL;
+ }
+}
+\f
+/* This enum encodes possible reasons for doing a target_wait, so that
+ wfi can call target_wait in one place. (Ultimately the call will be
+ moved out of the infinite loop entirely.) */
+
+enum infwait_states
+{
+ infwait_normal_state,
+ infwait_thread_hop_state,
+ infwait_nullified_state,
+ infwait_nonstep_watch_state
+};
+
+/* Why did the inferior stop? Used to print the appropriate messages
+ to the interface from within handle_inferior_event(). */
+enum inferior_stop_reason
+{
+ /* We don't know why. */
+ STOP_UNKNOWN,
+ /* Step, next, nexti, stepi finished. */
+ END_STEPPING_RANGE,
+ /* Found breakpoint. */
+ BREAKPOINT_HIT,
+ /* Inferior terminated by signal. */
+ SIGNAL_EXITED,
+ /* Inferior exited. */
+ EXITED,
+ /* Inferior received signal, and user asked to be notified. */
+ SIGNAL_RECEIVED
+};
+
+/* This structure contains what used to be local variables in
+ wait_for_inferior. Probably many of them can return to being
+ locals in handle_inferior_event. */
+
+struct execution_control_state
+ {
+ struct target_waitstatus ws;
+ struct target_waitstatus *wp;
+ int another_trap;
+ int random_signal;
+ CORE_ADDR stop_func_start;
+ CORE_ADDR stop_func_end;
+ char *stop_func_name;
+ struct symtab_and_line sal;
+ int remove_breakpoints_on_following_step;
+ int current_line;
+ struct symtab *current_symtab;
+ int handling_longjmp; /* FIXME */
+ int pid;
+ int saved_inferior_pid;
+ int update_step_sp;
+ int stepping_through_solib_after_catch;
+ bpstat stepping_through_solib_catchpoints;
+ int enable_hw_watchpoints_after_wait;
+ int stepping_through_sigtramp;
+ int new_thread_event;
+ struct target_waitstatus tmpstatus;
+ enum infwait_states infwait_state;
+ int waiton_pid;
+ int wait_some_more;
+ };
+
+void init_execution_control_state (struct execution_control_state * ecs);
+
+void handle_inferior_event (struct execution_control_state * ecs);
+
+static void check_sigtramp2 (struct execution_control_state *ecs);
+static void step_into_function (struct execution_control_state *ecs);
+static void step_over_function (struct execution_control_state *ecs);
+static void stop_stepping (struct execution_control_state *ecs);
+static void prepare_to_wait (struct execution_control_state *ecs);
+static void keep_going (struct execution_control_state *ecs);
+static void print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info);
+
+/* Wait for control to return from inferior to debugger.
+ If inferior gets a signal, we may decide to start it up again
+ instead of returning. That is why there is a loop in this function.
+ When this function actually returns it means the inferior
+ should be left stopped and GDB should read more commands. */
+
+void
+wait_for_inferior (void)
+{
+ struct cleanup *old_cleanups;
+ struct execution_control_state ecss;
+ struct execution_control_state *ecs;
+
+ old_cleanups = make_cleanup (delete_breakpoint_current_contents,
+ &step_resume_breakpoint);
+ make_cleanup (delete_breakpoint_current_contents,
+ &through_sigtramp_breakpoint);
+
+ /* wfi still stays in a loop, so it's OK just to take the address of
+ a local to get the ecs pointer. */
+ ecs = &ecss;
+
+ /* Fill in with reasonable starting values. */
+ init_execution_control_state (ecs);
+
+ thread_step_needed = 0;
+
+ /* We'll update this if & when we switch to a new thread. */
+ previous_inferior_pid = inferior_pid;
+
+ overlay_cache_invalid = 1;
+
+ /* We have to invalidate the registers BEFORE calling target_wait
+ because they can be loaded from the target while in target_wait.
+ This makes remote debugging a bit more efficient for those
+ targets that provide critical registers as part of their normal
+ status mechanism. */
+
+ registers_changed ();
+
+ while (1)
+ {
+ if (target_wait_hook)
+ ecs->pid = target_wait_hook (ecs->waiton_pid, ecs->wp);
+ else
+ ecs->pid = target_wait (ecs->waiton_pid, ecs->wp);
+
+ /* Now figure out what to do with the result of the result. */
+ handle_inferior_event (ecs);
+
+ if (!ecs->wait_some_more)
+ break;
+ }
+ do_cleanups (old_cleanups);
+}
+
+/* Asynchronous version of wait_for_inferior. It is called by the
+ event loop whenever a change of state is detected on the file
+ descriptor corresponding to the target. It can be called more than
+ once to complete a single execution command. In such cases we need
+ to keep the state in a global variable ASYNC_ECSS. If it is the
+ last time that this function is called for a single execution
+ command, then report to the user that the inferior has stopped, and
+ do the necessary cleanups. */
+
+struct execution_control_state async_ecss;
+struct execution_control_state *async_ecs;
+
+void
+fetch_inferior_event (client_data)
+ void *client_data;
+{
+ static struct cleanup *old_cleanups;
+
+ async_ecs = &async_ecss;
+
+ if (!async_ecs->wait_some_more)
+ {
+ old_cleanups = make_exec_cleanup (delete_breakpoint_current_contents,
+ &step_resume_breakpoint);
+ make_exec_cleanup (delete_breakpoint_current_contents,
+ &through_sigtramp_breakpoint);
+
+ /* Fill in with reasonable starting values. */
+ init_execution_control_state (async_ecs);
+
+ thread_step_needed = 0;
+
+ /* We'll update this if & when we switch to a new thread. */
+ previous_inferior_pid = inferior_pid;
+
+ overlay_cache_invalid = 1;
+
+ /* We have to invalidate the registers BEFORE calling target_wait
+ because they can be loaded from the target while in target_wait.
+ This makes remote debugging a bit more efficient for those
+ targets that provide critical registers as part of their normal
+ status mechanism. */
+
+ registers_changed ();
}
+
+ if (target_wait_hook)
+ async_ecs->pid = target_wait_hook (async_ecs->waiton_pid, async_ecs->wp);
else
+ async_ecs->pid = target_wait (async_ecs->waiton_pid, async_ecs->wp);
+
+ /* Now figure out what to do with the result of the result. */
+ handle_inferior_event (async_ecs);
+
+ if (!async_ecs->wait_some_more)
{
- wait_for_inferior ();
+ /* Do only the cleanups that have been added by this
+ function. Let the continuations for the commands do the rest,
+ if there are any. */
+ do_exec_cleanups (old_cleanups);
normal_stop ();
+ if (step_multi && stop_step)
+ inferior_event_handler (INF_EXEC_CONTINUE, NULL);
+ else
+ inferior_event_handler (INF_EXEC_COMPLETE, NULL);
}
}
-/* Start remote-debugging of a machine over a serial link. */
+/* Prepare an execution control state for looping through a
+ wait_for_inferior-type loop. */
void
-start_remote ()
+init_execution_control_state (struct execution_control_state *ecs)
{
- clear_proceed_status ();
- running_in_shell = 0;
- trap_expected = 0;
- inferior_pid = 3;
- breakpoints_inserted = 0;
- mark_breakpoints_out ();
- wait_for_inferior ();
- normal_stop();
+ /* ecs->another_trap? */
+ ecs->random_signal = 0;
+ ecs->remove_breakpoints_on_following_step = 0;
+ ecs->handling_longjmp = 0; /* FIXME */
+ ecs->update_step_sp = 0;
+ ecs->stepping_through_solib_after_catch = 0;
+ ecs->stepping_through_solib_catchpoints = NULL;
+ ecs->enable_hw_watchpoints_after_wait = 0;
+ ecs->stepping_through_sigtramp = 0;
+ ecs->sal = find_pc_line (prev_pc, 0);
+ ecs->current_line = ecs->sal.line;
+ ecs->current_symtab = ecs->sal.symtab;
+ ecs->infwait_state = infwait_normal_state;
+ ecs->waiton_pid = -1;
+ ecs->wp = &(ecs->ws);
}
-#ifdef ATTACH_DETACH
+/* Call this function before setting step_resume_breakpoint, as a
+ sanity check. There should never be more than one step-resume
+ breakpoint per thread, so we should never be setting a new
+ step_resume_breakpoint when one is already active. */
+static void
+check_for_old_step_resume_breakpoint (void)
+{
+ if (step_resume_breakpoint)
+ warning ("GDB bug: infrun.c (wait_for_inferior): dropping old step_resume breakpoint");
+}
-/* Attach to process PID, then initialize for debugging it
- and wait for the trace-trap that results from attaching. */
+/* Given an execution control state that has been freshly filled in
+ by an event from the inferior, figure out what it means and take
+ appropriate action. */
void
-attach_program (pid)
- int pid;
+handle_inferior_event (struct execution_control_state *ecs)
{
- attach (pid);
- inferior_pid = pid;
+ CORE_ADDR tmp;
+ int stepped_after_stopped_by_watchpoint;
- mark_breakpoints_out ();
- terminal_init_inferior ();
- clear_proceed_status ();
- stop_after_attach = 1;
- /*proceed (-1, 0, -2);*/
- terminal_inferior ();
- wait_for_inferior ();
- normal_stop ();
-}
-#endif /* ATTACH_DETACH */
-\f
-/* 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. */
+ /* Keep this extra brace for now, minimizes diffs. */
+ {
+ switch (ecs->infwait_state)
+ {
+ case infwait_normal_state:
+ /* Since we've done a wait, we have a new event. Don't
+ carry over any expectations about needing to step over a
+ breakpoint. */
+ thread_step_needed = 0;
+
+ /* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
+ is serviced in this loop, below. */
+ if (ecs->enable_hw_watchpoints_after_wait)
+ {
+ TARGET_ENABLE_HW_WATCHPOINTS (inferior_pid);
+ ecs->enable_hw_watchpoints_after_wait = 0;
+ }
+ stepped_after_stopped_by_watchpoint = 0;
+ break;
+
+ case infwait_thread_hop_state:
+ insert_breakpoints ();
+
+ /* We need to restart all the threads now,
+ * unles we're running in scheduler-locked mode.
+ * FIXME: shouldn't we look at currently_stepping ()?
+ */
+ if (scheduler_mode == schedlock_on)
+ target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
+ else
+ target_resume (-1, 0, TARGET_SIGNAL_0);
+ ecs->infwait_state = infwait_normal_state;
+ prepare_to_wait (ecs);
+ return;
+
+ case infwait_nullified_state:
+ break;
+
+ case infwait_nonstep_watch_state:
+ insert_breakpoints ();
+
+ /* FIXME-maybe: is this cleaner than setting a flag? Does it
+ handle things like signals arriving and other things happening
+ in combination correctly? */
+ stepped_after_stopped_by_watchpoint = 1;
+ break;
+ }
+ ecs->infwait_state = infwait_normal_state;
-static void
-wait_for_inferior ()
-{
- register int pid;
- WAITTYPE w;
- CORE_ADDR pc;
- int tem;
- int another_trap;
- int random_signal;
- CORE_ADDR stop_sp, prev_sp;
- CORE_ADDR prev_func_start, stop_func_start;
- char *prev_func_name, *stop_func_name;
- CORE_ADDR prologue_pc;
- int stop_step_resume_break;
- CORE_ADDR step_resume_break_sp;
- int newmisc;
- int newfun_pc;
- struct symtab_and_line sal;
- int prev_pc;
- extern CORE_ADDR text_end;
- int remove_breakpoints_on_following_step = 0;
-
- prev_pc = read_pc ();
- (void) find_pc_partial_function (prev_pc, &prev_func_name,
- &prev_func_start);
- prev_func_start += FUNCTION_START_OFFSET;
- prev_sp = read_register (SP_REGNUM);
+ flush_cached_frames ();
- while (1)
- {
- /* Clean up saved state that will become invalid. */
- pc_changed = 0;
- flush_cached_frames ();
+ /* If it's a new process, add it to the thread database */
- if (remote_debugging)
- remote_wait (&w);
- else
- {
- pid = wait (&w);
- if (pid != inferior_pid)
- continue;
- }
+ ecs->new_thread_event = ((ecs->pid != inferior_pid) && !in_thread_list (ecs->pid));
- /* See if the process still exists; clean up if it doesn't. */
- if (WIFEXITED (w))
- {
- terminal_ours_for_output ();
- if (WRETCODE (w))
- printf ("\nProgram exited with code 0%o.\n", WRETCODE (w));
- else
- printf ("\nProgram exited normally.\n");
- fflush (stdout);
- inferior_died ();
-#ifdef NO_SINGLE_STEP
- one_stepped = 0;
+ if (ecs->ws.kind != TARGET_WAITKIND_EXITED
+ && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
+ && ecs->new_thread_event)
+ {
+ add_thread (ecs->pid);
+
+#ifdef UI_OUT
+ ui_out_text (uiout, "[New ");
+ ui_out_text (uiout, target_pid_or_tid_to_str (ecs->pid));
+ ui_out_text (uiout, "]\n");
+#else
+ printf_filtered ("[New %s]\n", target_pid_or_tid_to_str (ecs->pid));
#endif
- stop_print_frame = 0;
- break;
- }
- else if (!WIFSTOPPED (w))
+
+#if 0
+ /* NOTE: This block is ONLY meant to be invoked in case of a
+ "thread creation event"! If it is invoked for any other
+ sort of event (such as a new thread landing on a breakpoint),
+ the event will be discarded, which is almost certainly
+ a bad thing!
+
+ To avoid this, the low-level module (eg. target_wait)
+ should call in_thread_list and add_thread, so that the
+ new thread is known by the time we get here. */
+
+ /* We may want to consider not doing a resume here in order
+ to give the user a chance to play with the new thread.
+ It might be good to make that a user-settable option. */
+
+ /* At this point, all threads are stopped (happens
+ automatically in either the OS or the native code).
+ Therefore we need to continue all threads in order to
+ make progress. */
+
+ target_resume (-1, 0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+#endif
+ }
+
+ switch (ecs->ws.kind)
+ {
+ case TARGET_WAITKIND_LOADED:
+ /* Ignore gracefully during startup of the inferior, as it
+ might be the shell which has just loaded some objects,
+ otherwise add the symbols for the newly loaded objects. */
+#ifdef SOLIB_ADD
+ if (!stop_soon_quietly)
+ {
+ /* Remove breakpoints, SOLIB_ADD might adjust
+ breakpoint addresses via breakpoint_re_set. */
+ if (breakpoints_inserted)
+ remove_breakpoints ();
+
+ /* Check for any newly added shared libraries if we're
+ supposed to be adding them automatically. */
+ 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);
+ prepare_to_wait (ecs);
+ return;
+
+ case TARGET_WAITKIND_SPURIOUS:
+ resume (0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+
+ case TARGET_WAITKIND_EXITED:
+ target_terminal_ours (); /* Must do this before mourn anyway */
+ print_stop_reason (EXITED, ecs->ws.value.integer);
+
+ /* Record the exit code in the convenience variable $_exitcode, so
+ that the user can inspect this again later. */
+ set_internalvar (lookup_internalvar ("_exitcode"),
+ value_from_longest (builtin_type_int,
+ (LONGEST) ecs->ws.value.integer));
+ gdb_flush (gdb_stdout);
+ target_mourn_inferior ();
+ singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P */
+ stop_print_frame = 0;
+ stop_stepping (ecs);
+ return;
+
+ case TARGET_WAITKIND_SIGNALLED:
+ stop_print_frame = 0;
+ stop_signal = ecs->ws.value.sig;
+ target_terminal_ours (); /* Must do this before mourn anyway */
+
+ /* This looks pretty bogus to me. Doesn't TARGET_WAITKIND_SIGNALLED
+ mean it is already dead? This has been here since GDB 2.8, so
+ perhaps it means rms didn't understand unix waitstatuses?
+ For the moment I'm just kludging around this in remote.c
+ rather than trying to change it here --kingdon, 5 Dec 1994. */
+ target_kill (); /* kill mourns as well */
+
+ print_stop_reason (SIGNAL_EXITED, stop_signal);
+ singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P */
+ stop_stepping (ecs);
+ return;
+
+ /* The following are the only cases in which we keep going;
+ the above cases end in a continue or goto. */
+ case TARGET_WAITKIND_FORKED:
+ stop_signal = TARGET_SIGNAL_TRAP;
+ pending_follow.kind = ecs->ws.kind;
+
+ /* Ignore fork events reported for the parent; we're only
+ interested in reacting to forks of the child. Note that
+ we expect the child's fork event to be available if we
+ waited for it now. */
+ if (inferior_pid == ecs->pid)
+ {
+ pending_follow.fork_event.saw_parent_fork = 1;
+ pending_follow.fork_event.parent_pid = ecs->pid;
+ pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
+ prepare_to_wait (ecs);
+ return;
+ }
+ else
+ {
+ pending_follow.fork_event.saw_child_fork = 1;
+ pending_follow.fork_event.child_pid = ecs->pid;
+ pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
+ }
+
+ stop_pc = read_pc_pid (ecs->pid);
+ ecs->saved_inferior_pid = inferior_pid;
+ inferior_pid = ecs->pid;
+ stop_bpstat = bpstat_stop_status (&stop_pc, currently_stepping (ecs));
+ ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
+ inferior_pid = ecs->saved_inferior_pid;
+ goto process_event_stop_test;
+
+ /* If this a platform which doesn't allow a debugger to touch a
+ vfork'd inferior until after it exec's, then we'd best keep
+ our fingers entirely off the inferior, other than continuing
+ it. This has the unfortunate side-effect that catchpoints
+ of vforks will be ignored. But since the platform doesn't
+ allow the inferior be touched at vfork time, there's really
+ little choice. */
+ case TARGET_WAITKIND_VFORKED:
+ stop_signal = TARGET_SIGNAL_TRAP;
+ pending_follow.kind = ecs->ws.kind;
+
+ /* Is this a vfork of the parent? If so, then give any
+ vfork catchpoints a chance to trigger now. (It's
+ dangerous to do so if the child canot be touched until
+ it execs, and the child has not yet exec'd. We probably
+ should warn the user to that effect when the catchpoint
+ triggers...) */
+ if (ecs->pid == inferior_pid)
+ {
+ pending_follow.fork_event.saw_parent_fork = 1;
+ pending_follow.fork_event.parent_pid = ecs->pid;
+ pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
+ }
+
+ /* If we've seen the child's vfork event but cannot really touch
+ the child until it execs, then we must continue the child now.
+ Else, give any vfork catchpoints a chance to trigger now. */
+ else
+ {
+ pending_follow.fork_event.saw_child_fork = 1;
+ pending_follow.fork_event.child_pid = ecs->pid;
+ pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
+ target_post_startup_inferior (pending_follow.fork_event.child_pid);
+ follow_vfork_when_exec = !target_can_follow_vfork_prior_to_exec ();
+ if (follow_vfork_when_exec)
+ {
+ target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+ }
+ }
+
+ stop_pc = read_pc ();
+ stop_bpstat = bpstat_stop_status (&stop_pc, currently_stepping (ecs));
+ ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
+ goto process_event_stop_test;
+
+ case TARGET_WAITKIND_EXECD:
+ stop_signal = TARGET_SIGNAL_TRAP;
+
+ /* Is this a target which reports multiple exec events per actual
+ call to exec()? (HP-UX using ptrace does, for example.) If so,
+ ignore all but the last one. Just resume the exec'r, and wait
+ for the next exec event. */
+ if (inferior_ignoring_leading_exec_events)
+ {
+ inferior_ignoring_leading_exec_events--;
+ if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
+ ENSURE_VFORKING_PARENT_REMAINS_STOPPED (pending_follow.fork_event.parent_pid);
+ target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+ }
+ inferior_ignoring_leading_exec_events =
+ target_reported_exec_events_per_exec_call () - 1;
+
+ pending_follow.execd_pathname =
+ savestring (ecs->ws.value.execd_pathname,
+ strlen (ecs->ws.value.execd_pathname));
+
+ /* Did inferior_pid exec, or did a (possibly not-yet-followed)
+ child of a vfork exec?
+
+ ??rehrauer: This is unabashedly an HP-UX specific thing. On
+ HP-UX, events associated with a vforking inferior come in
+ threes: a vfork event for the child (always first), followed
+ a vfork event for the parent and an exec event for the child.
+ The latter two can come in either order.
+
+ If we get the parent vfork event first, life's good: We follow
+ either the parent or child, and then the child's exec event is
+ a "don't care".
+
+ But if we get the child's exec event first, then we delay
+ responding to it until we handle the parent's vfork. Because,
+ otherwise we can't satisfy a "catch vfork". */
+ if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
+ {
+ pending_follow.fork_event.saw_child_exec = 1;
+
+ /* On some targets, the child must be resumed before
+ the parent vfork event is delivered. A single-step
+ suffices. */
+ if (RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK ())
+ target_resume (ecs->pid, 1, TARGET_SIGNAL_0);
+ /* We expect the parent vfork event to be available now. */
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ /* This causes the eventpoints and symbol table to be reset. Must
+ do this now, before trying to determine whether to stop. */
+ follow_exec (inferior_pid, pending_follow.execd_pathname);
+ free (pending_follow.execd_pathname);
+
+ stop_pc = read_pc_pid (ecs->pid);
+ ecs->saved_inferior_pid = inferior_pid;
+ inferior_pid = ecs->pid;
+ stop_bpstat = bpstat_stop_status (&stop_pc, currently_stepping (ecs));
+ ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
+ inferior_pid = ecs->saved_inferior_pid;
+ goto process_event_stop_test;
+
+ /* These syscall events are returned on HP-UX, as part of its
+ implementation of page-protection-based "hardware" watchpoints.
+ HP-UX has unfortunate interactions between page-protections and
+ some system calls. Our solution is to disable hardware watches
+ when a system call is entered, and reenable them when the syscall
+ completes. The downside of this is that we may miss the precise
+ point at which a watched piece of memory is modified. "Oh well."
+
+ Note that we may have multiple threads running, which may each
+ enter syscalls at roughly the same time. Since we don't have a
+ good notion currently of whether a watched piece of memory is
+ thread-private, we'd best not have any page-protections active
+ when any thread is in a syscall. Thus, we only want to reenable
+ hardware watches when no threads are in a syscall.
+
+ Also, be careful not to try to gather much state about a thread
+ that's in a syscall. It's frequently a losing proposition. */
+ case TARGET_WAITKIND_SYSCALL_ENTRY:
+ number_of_threads_in_syscalls++;
+ if (number_of_threads_in_syscalls == 1)
+ {
+ TARGET_DISABLE_HW_WATCHPOINTS (inferior_pid);
+ }
+ resume (0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+
+ /* Before examining the threads further, step this thread to
+ get it entirely out of the syscall. (We get notice of the
+ event when the thread is just on the verge of exiting a
+ syscall. Stepping one instruction seems to get it back
+ into user code.)
+
+ Note that although the logical place to reenable h/w watches
+ is here, we cannot. We cannot reenable them before stepping
+ the thread (this causes the next wait on the thread to hang).
+
+ Nor can we enable them after stepping until we've done a wait.
+ Thus, we simply set the flag ecs->enable_hw_watchpoints_after_wait
+ here, which will be serviced immediately after the target
+ is waited on. */
+ case TARGET_WAITKIND_SYSCALL_RETURN:
+ target_resume (ecs->pid, 1, TARGET_SIGNAL_0);
+
+ if (number_of_threads_in_syscalls > 0)
+ {
+ number_of_threads_in_syscalls--;
+ ecs->enable_hw_watchpoints_after_wait =
+ (number_of_threads_in_syscalls == 0);
+ }
+ prepare_to_wait (ecs);
+ return;
+
+ case TARGET_WAITKIND_STOPPED:
+ stop_signal = ecs->ws.value.sig;
+ break;
+
+ /* We had an event in the inferior, but we are not interested
+ in handling it at this level. The lower layers have already
+ done what needs to be done, if anything. This case can
+ occur only when the target is async or extended-async. One
+ of the circumstamces for this to happen is when the
+ inferior produces output for the console. The inferior has
+ not stopped, and we are ignoring the event. */
+ case TARGET_WAITKIND_IGNORE:
+ ecs->wait_some_more = 1;
+ return;
+ }
+
+ /* We may want to consider not doing a resume here in order to give
+ the user a chance to play with the new thread. It might be good
+ to make that a user-settable option. */
+
+ /* At this point, all threads are stopped (happens automatically in
+ either the OS or the native code). Therefore we need to continue
+ all threads in order to make progress. */
+ if (ecs->new_thread_event)
+ {
+ target_resume (-1, 0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ stop_pc = read_pc_pid (ecs->pid);
+
+ /* See if a thread hit a thread-specific breakpoint that was meant for
+ another thread. If so, then step that thread past the breakpoint,
+ and continue it. */
+
+ if (stop_signal == TARGET_SIGNAL_TRAP)
+ {
+ if (SOFTWARE_SINGLE_STEP_P && singlestep_breakpoints_inserted_p)
+ ecs->random_signal = 0;
+ else if (breakpoints_inserted
+ && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK))
+ {
+ ecs->random_signal = 0;
+ if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK,
+ ecs->pid))
+ {
+ int remove_status;
+
+ /* Saw a breakpoint, but it was hit by the wrong thread.
+ Just continue. */
+ write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, ecs->pid);
+
+ remove_status = remove_breakpoints ();
+ /* Did we fail to remove breakpoints? If so, try
+ to set the PC past the bp. (There's at least
+ one situation in which we can fail to remove
+ the bp's: On HP-UX's that use ttrace, we can't
+ change the address space of a vforking child
+ process until the child exits (well, okay, not
+ then either :-) or execs. */
+ if (remove_status != 0)
+ {
+ write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK + 4, ecs->pid);
+ }
+ else
+ { /* Single step */
+ target_resume (ecs->pid, 1, TARGET_SIGNAL_0);
+ /* FIXME: What if a signal arrives instead of the
+ single-step happening? */
+
+ ecs->waiton_pid = ecs->pid;
+ ecs->wp = &(ecs->ws);
+ ecs->infwait_state = infwait_thread_hop_state;
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ /* We need to restart all the threads now,
+ * unles we're running in scheduler-locked mode.
+ * FIXME: shouldn't we look at currently_stepping ()?
+ */
+ if (scheduler_mode == schedlock_on)
+ target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
+ else
+ target_resume (-1, 0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+ }
+ else
+ {
+ /* This breakpoint matches--either it is the right
+ thread or it's a generic breakpoint for all threads.
+ Remember that we'll need to step just _this_ thread
+ on any following user continuation! */
+ thread_step_needed = 1;
+ }
+ }
+ }
+ else
+ ecs->random_signal = 1;
+
+ /* See if something interesting happened to the non-current thread. If
+ so, then switch to that thread, and eventually give control back to
+ the user.
+
+ Note that if there's any kind of pending follow (i.e., of a fork,
+ vfork or exec), we don't want to do this now. Rather, we'll let
+ the next resume handle it. */
+ if ((ecs->pid != inferior_pid) &&
+ (pending_follow.kind == TARGET_WAITKIND_SPURIOUS))
+ {
+ int printed = 0;
+
+ /* If it's a random signal for a non-current thread, notify user
+ if he's expressed an interest. */
+ if (ecs->random_signal
+ && signal_print[stop_signal])
+ {
+/* ??rehrauer: I don't understand the rationale for this code. If the
+ inferior will stop as a result of this signal, then the act of handling
+ the stop ought to print a message that's couches the stoppage in user
+ terms, e.g., "Stopped for breakpoint/watchpoint". If the inferior
+ won't stop as a result of the signal -- i.e., if the signal is merely
+ a side-effect of something GDB's doing "under the covers" for the
+ user, such as stepping threads over a breakpoint they shouldn't stop
+ for -- then the message seems to be a serious annoyance at best.
+
+ For now, remove the message altogether. */
+#if 0
+ printed = 1;
+ target_terminal_ours_for_output ();
+ printf_filtered ("\nProgram received signal %s, %s.\n",
+ target_signal_to_name (stop_signal),
+ target_signal_to_string (stop_signal));
+ gdb_flush (gdb_stdout);
+#endif
+ }
+
+ /* If it's not SIGTRAP and not a signal we want to stop for, then
+ continue the thread. */
+
+ if (stop_signal != TARGET_SIGNAL_TRAP
+ && !signal_stop[stop_signal])
+ {
+ if (printed)
+ target_terminal_inferior ();
+
+ /* Clear the signal if it should not be passed. */
+ if (signal_program[stop_signal] == 0)
+ stop_signal = TARGET_SIGNAL_0;
+
+ target_resume (ecs->pid, 0, stop_signal);
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ /* It's a SIGTRAP or a signal we're interested in. Switch threads,
+ and fall into the rest of wait_for_inferior(). */
+
+ /* Caution: it may happen that the new thread (or the old one!)
+ is not in the thread list. In this case we must not attempt
+ to "switch context", or we run the risk that our context may
+ be lost. This may happen as a result of the target module
+ mishandling thread creation. */
+
+ if (in_thread_list (inferior_pid) && in_thread_list (ecs->pid))
+ { /* Perform infrun state context switch: */
+ /* Save infrun state for the old thread. */
+ save_infrun_state (inferior_pid, prev_pc,
+ prev_func_start, prev_func_name,
+ trap_expected, step_resume_breakpoint,
+ through_sigtramp_breakpoint,
+ step_range_start, step_range_end,
+ step_frame_address, ecs->handling_longjmp,
+ ecs->another_trap,
+ ecs->stepping_through_solib_after_catch,
+ ecs->stepping_through_solib_catchpoints,
+ ecs->stepping_through_sigtramp);
+
+ /* Load infrun state for the new thread. */
+ load_infrun_state (ecs->pid, &prev_pc,
+ &prev_func_start, &prev_func_name,
+ &trap_expected, &step_resume_breakpoint,
+ &through_sigtramp_breakpoint,
+ &step_range_start, &step_range_end,
+ &step_frame_address, &ecs->handling_longjmp,
+ &ecs->another_trap,
+ &ecs->stepping_through_solib_after_catch,
+ &ecs->stepping_through_solib_catchpoints,
+ &ecs->stepping_through_sigtramp);
+ }
+
+ inferior_pid = ecs->pid;
+
+ if (context_hook)
+ context_hook (pid_to_thread_id (ecs->pid));
+
+ flush_cached_frames ();
+ }
+
+ if (SOFTWARE_SINGLE_STEP_P && singlestep_breakpoints_inserted_p)
+ {
+ /* Pull the single step breakpoints out of the target. */
+ SOFTWARE_SINGLE_STEP (0, 0);
+ singlestep_breakpoints_inserted_p = 0;
+ }
+
+ /* If PC is pointing at a nullified instruction, then step beyond
+ it so that the user won't be confused when GDB appears to be ready
+ to execute it. */
+
+ /* if (INSTRUCTION_NULLIFIED && currently_stepping (ecs)) */
+ if (INSTRUCTION_NULLIFIED)
+ {
+ registers_changed ();
+ target_resume (ecs->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 WS. */
+
+ ecs->infwait_state = infwait_nullified_state;
+ ecs->waiton_pid = ecs->pid;
+ ecs->wp = &(ecs->tmpstatus);
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ /* It may not be necessary to disable the watchpoint to stop over
+ it. For example, the PA can (with some kernel cooperation)
+ single step over a watchpoint without disabling the watchpoint. */
+ if (HAVE_STEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
+ {
+ resume (1, 0);
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ /* It is far more common to need to disable a watchpoint to step
+ the inferior over it. FIXME. What else might a debug
+ register or page protection watchpoint scheme need here? */
+ if (HAVE_NONSTEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
+ {
+ /* At this point, we are stopped at an instruction which has
+ attempted to write to a piece of memory under control of
+ a watchpoint. The instruction hasn't actually executed
+ yet. If we were to evaluate the watchpoint expression
+ now, we would get the old value, and therefore no change
+ would seem to have occurred.
+
+ In order to make watchpoints work `right', we really need
+ to complete the memory write, and then evaluate the
+ watchpoint expression. The following code does that by
+ removing the watchpoint (actually, all watchpoints and
+ breakpoints), single-stepping the target, re-inserting
+ watchpoints, and then falling through to let normal
+ single-step processing handle proceed. Since this
+ includes evaluating watchpoints, things will come to a
+ stop in the correct manner. */
+
+ write_pc (stop_pc - DECR_PC_AFTER_BREAK);
+
+ remove_breakpoints ();
+ registers_changed ();
+ target_resume (ecs->pid, 1, TARGET_SIGNAL_0); /* Single step */
+
+ ecs->waiton_pid = ecs->pid;
+ ecs->wp = &(ecs->ws);
+ ecs->infwait_state = infwait_nonstep_watch_state;
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ /* It may be possible to simply continue after a watchpoint. */
+ if (HAVE_CONTINUABLE_WATCHPOINT)
+ STOPPED_BY_WATCHPOINT (ecs->ws);
+
+ ecs->stop_func_start = 0;
+ ecs->stop_func_end = 0;
+ ecs->stop_func_name = 0;
+ /* Don't care about return value; stop_func_start and stop_func_name
+ will both be 0 if it doesn't work. */
+ find_pc_partial_function (stop_pc, &ecs->stop_func_name,
+ &ecs->stop_func_start, &ecs->stop_func_end);
+ ecs->stop_func_start += FUNCTION_START_OFFSET;
+ ecs->another_trap = 0;
+ bpstat_clear (&stop_bpstat);
+ stop_step = 0;
+ stop_stack_dummy = 0;
+ stop_print_frame = 1;
+ ecs->random_signal = 0;
+ stopped_by_random_signal = 0;
+ breakpoints_failed = 0;
+
+ /* Look at the cause of the stop, and decide what to do.
+ The alternatives are:
+ 1) break; to really stop and return to the debugger,
+ 2) drop through to start up again
+ (set ecs->another_trap to 1 to single step once)
+ 3) set ecs->random_signal to 1, and the decision between 1 and 2
+ will be made according to the signal handling tables. */
+
+ /* First, distinguish signals caused by the debugger from signals
+ that have to do with the program's own actions.
+ Note that breakpoint insns may cause SIGTRAP or SIGILL
+ or SIGEMT, depending on the operating system version.
+ Here we detect when a SIGILL or SIGEMT is really a breakpoint
+ and change it to SIGTRAP. */
+
+ if (stop_signal == TARGET_SIGNAL_TRAP
+ || (breakpoints_inserted &&
+ (stop_signal == TARGET_SIGNAL_ILL
+ || stop_signal == TARGET_SIGNAL_EMT
+ ))
+ || stop_soon_quietly)
+ {
+ if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
+ {
+ stop_print_frame = 0;
+ stop_stepping (ecs);
+ return;
+ }
+ if (stop_soon_quietly)
+ {
+ stop_stepping (ecs);
+ return;
+ }
+
+ /* Don't even think about breakpoints
+ if just proceeded over a breakpoint.
+
+ However, if we are trying to proceed over a breakpoint
+ and end up in sigtramp, then through_sigtramp_breakpoint
+ will be set and we should check whether we've hit the
+ step breakpoint. */
+ if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected
+ && through_sigtramp_breakpoint == NULL)
+ bpstat_clear (&stop_bpstat);
+ else
+ {
+ /* See if there is a breakpoint at the current PC. */
+ stop_bpstat = bpstat_stop_status
+ (&stop_pc,
+ /* Pass TRUE if our reason for stopping is something other
+ than hitting a breakpoint. We do this by checking that
+ 1) stepping is going on and 2) 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 (ecs)
+ && !(step_range_end
+ && INNER_THAN (read_sp (), (step_sp - 16))))
+ );
+ /* Following in case break condition called a
+ function. */
+ stop_print_frame = 1;
+ }
+
+ if (stop_signal == TARGET_SIGNAL_TRAP)
+ ecs->random_signal
+ = !(bpstat_explains_signal (stop_bpstat)
+ || trap_expected
+ || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
+ && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
+ FRAME_FP (get_current_frame ())))
+ || (step_range_end && step_resume_breakpoint == NULL));
+
+ else
+ {
+ ecs->random_signal
+ = !(bpstat_explains_signal (stop_bpstat)
+ /* End of a stack dummy. Some systems (e.g. Sony
+ news) give another signal besides SIGTRAP, so
+ check here as well as above. */
+ || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
+ && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
+ FRAME_FP (get_current_frame ())))
+ );
+ if (!ecs->random_signal)
+ stop_signal = TARGET_SIGNAL_TRAP;
+ }
+ }
+
+ /* When we reach this point, we've pretty much decided
+ that the reason for stopping must've been a random
+ (unexpected) signal. */
+
+ else
+ ecs->random_signal = 1;
+ /* If a fork, vfork or exec event was seen, then there are two
+ possible responses we can make:
+
+ 1. If a catchpoint triggers for the event (ecs->random_signal == 0),
+ then we must stop now and issue a prompt. We will resume
+ the inferior when the user tells us to.
+ 2. If no catchpoint triggers for the event (ecs->random_signal == 1),
+ then we must resume the inferior now and keep checking.
+
+ In either case, we must take appropriate steps to "follow" the
+ the fork/vfork/exec when the inferior is resumed. For example,
+ if follow-fork-mode is "child", then we must detach from the
+ parent inferior and follow the new child inferior.
+
+ In either case, setting pending_follow causes the next resume()
+ to take the appropriate following action. */
+ process_event_stop_test:
+ if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
+ {
+ if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
+ {
+ trap_expected = 1;
+ stop_signal = TARGET_SIGNAL_0;
+ keep_going (ecs);
+ return;
+ }
+ }
+ else if (ecs->ws.kind == TARGET_WAITKIND_VFORKED)
+ {
+ if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
+ {
+ stop_signal = TARGET_SIGNAL_0;
+ keep_going (ecs);
+ return;
+ }
+ }
+ else if (ecs->ws.kind == TARGET_WAITKIND_EXECD)
+ {
+ pending_follow.kind = ecs->ws.kind;
+ if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
+ {
+ trap_expected = 1;
+ stop_signal = TARGET_SIGNAL_0;
+ keep_going (ecs);
+ return;
+ }
+ }
+
+ /* For the program's own signals, act according to
+ the signal handling tables. */
+
+ if (ecs->random_signal)
+ {
+ /* Signal not for debugging purposes. */
+ int printed = 0;
+
+ stopped_by_random_signal = 1;
+
+ if (signal_print[stop_signal])
+ {
+ printed = 1;
+ target_terminal_ours_for_output ();
+ print_stop_reason (SIGNAL_RECEIVED, stop_signal);
+ }
+ if (signal_stop[stop_signal])
+ {
+ stop_stepping (ecs);
+ return;
+ }
+ /* If not going to stop, give terminal back
+ if we took it away. */
+ else if (printed)
+ target_terminal_inferior ();
+
+ /* Clear the signal if it should not be passed. */
+ if (signal_program[stop_signal] == 0)
+ stop_signal = TARGET_SIGNAL_0;
+
+ /* I'm not sure whether this needs to be check_sigtramp2 or
+ whether it could/should be keep_going.
+
+ This used to jump to step_over_function if we are stepping,
+ which is wrong.
+
+ Suppose the user does a `next' over a function call, and while
+ that call is in progress, the inferior receives a signal for
+ which GDB does not stop (i.e., signal_stop[SIG] is false). In
+ that case, when we reach this point, there is already a
+ step-resume breakpoint established, right where it should be:
+ immediately after the function call the user is "next"-ing
+ over. If we call step_over_function now, two bad things
+ happen:
+
+ - we'll create a new breakpoint, at wherever the current
+ frame's return address happens to be. That could be
+ anywhere, depending on what function call happens to be on
+ the top of the stack at that point. Point is, it's probably
+ not where we need it.
+
+ - the existing step-resume breakpoint (which is at the correct
+ address) will get orphaned: step_resume_breakpoint will point
+ to the new breakpoint, and the old step-resume breakpoint
+ will never be cleaned up.
+
+ The old behavior was meant to help HP-UX single-step out of
+ sigtramps. It would place the new breakpoint at prev_pc, which
+ was certainly wrong. I don't know the details there, so fixing
+ this probably breaks that. As with anything else, it's up to
+ the HP-UX maintainer to furnish a fix that doesn't break other
+ platforms. --JimB, 20 May 1999 */
+ check_sigtramp2 (ecs);
+ }
+
+ /* Handle cases caused by hitting a breakpoint. */
+ {
+ CORE_ADDR jmp_buf_pc;
+ struct bpstat_what what;
+
+ what = bpstat_what (stop_bpstat);
+
+ if (what.call_dummy)
{
- kill_inferior ();
- stop_print_frame = 0;
- stop_signal = WTERMSIG (w);
- terminal_ours_for_output ();
- printf ("\nProgram terminated with signal %d, %s\n",
- stop_signal,
- stop_signal < NSIG
- ? sys_siglist[stop_signal]
- : "(undocumented)");
- printf ("The inferior process no longer exists.\n");
- fflush (stdout);
-#ifdef NO_SINGLE_STEP
- one_stepped = 0;
+ stop_stack_dummy = 1;
+#ifdef HP_OS_BUG
+ trap_expected_after_continue = 1;
#endif
- break;
}
-
-#ifdef NO_SINGLE_STEP
- if (one_stepped)
- single_step (0); /* This actually cleans up the ss */
-#endif /* NO_SINGLE_STEP */
-
- fetch_inferior_registers ();
- 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;
- stop_breakpoint = 0;
- 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
- || stop_signal == SIGEMT))
- || stop_after_attach)
+
+ switch (what.main_action)
{
- if (stop_signal == SIGTRAP && stop_after_trap)
+ case BPSTAT_WHAT_SET_LONGJMP_RESUME:
+ /* If we hit the breakpoint at longjmp, disable it for the
+ duration of this command. Then, install a temporary
+ breakpoint at the target of the jmp_buf. */
+ disable_longjmp_breakpoint ();
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
+ if (!GET_LONGJMP_TARGET (&jmp_buf_pc))
{
- stop_print_frame = 0;
- break;
+ keep_going (ecs);
+ return;
}
- if (stop_after_attach)
- break;
- /* Don't even think about breakpoints
- if still running the shell that will exec the program
- or if just proceeded over a breakpoint. */
- if (stop_signal == SIGTRAP && trap_expected)
- stop_breakpoint = 0;
- else
+
+ /* Need to blow away step-resume breakpoint, as it
+ interferes with us */
+ if (step_resume_breakpoint != NULL)
{
- /* See if there is a breakpoint at the current PC. */
-#if DECR_PC_AFTER_BREAK
- /* Notice the case of stepping through a jump
- that leads 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))
-#endif /* DECR_PC_AFTER_BREAK not zero */
- {
- /* See if we stopped at the special breakpoint for
- stepping over a subroutine call. */
- if (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_breakpoint =
- breakpoint_stop_status (stop_pc, stop_frame_address);
- /* Following in case break condition called a
- function. */
- stop_print_frame = 1;
- if (stop_breakpoint && DECR_PC_AFTER_BREAK)
- {
- stop_pc -= DECR_PC_AFTER_BREAK;
- write_register (PC_REGNUM, stop_pc);
-#ifdef NPC_REGNUM
- write_register (NPC_REGNUM, stop_pc + 4);
-#endif
- pc_changed = 0;
- }
- }
- }
+ delete_breakpoint (step_resume_breakpoint);
+ step_resume_breakpoint = NULL;
}
-
- if (stop_signal == SIGTRAP)
- random_signal
- = !(stop_breakpoint || trap_expected
- || stop_step_resume_break
-#ifndef CANNOT_EXECUTE_STACK
- || (stop_sp INNER_THAN stop_pc
- && stop_pc INNER_THAN stop_frame_address)
-#else
- || stop_pc == text_end - 2
-#endif
- || (step_range_end && !step_resume_break_address));
- else
+ /* Not sure whether we need to blow this away too, but probably
+ it is like the step-resume breakpoint. */
+ if (through_sigtramp_breakpoint != NULL)
{
- random_signal
- = !(stop_breakpoint
- || stop_step_resume_break
-#ifdef sony_news
- || (stop_sp INNER_THAN stop_pc
- && stop_pc INNER_THAN stop_frame_address)
-#endif
-
- );
- if (!random_signal)
- stop_signal = SIGTRAP;
+ delete_breakpoint (through_sigtramp_breakpoint);
+ through_sigtramp_breakpoint = NULL;
}
- }
- else
- random_signal = 1;
-
- /* For the program's own signals, act according to
- the signal handling tables. */
-
- if (random_signal
- && !(running_in_shell && stop_signal == SIGSEGV))
- {
- /* Signal not for debugging purposes. */
- int printed = 0;
-
- stopped_by_random_signal = 1;
-
- if (stop_signal >= NSIG
- || signal_print[stop_signal])
+
+#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);
+ ecs->handling_longjmp = 1; /* FIXME */
+ keep_going (ecs);
+ return;
+
+ case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
+ case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
+#if 0
+ /* FIXME - Need to implement nested temporary breakpoints */
+ if (step_over_calls
+ && (INNER_THAN (FRAME_FP (get_current_frame ()),
+ step_frame_address)))
{
- printed = 1;
- terminal_ours_for_output ();
- printf ("\nProgram received signal %d, %s\n",
- stop_signal,
- stop_signal < NSIG
- ? sys_siglist[stop_signal]
- : "(undocumented)");
- fflush (stdout);
+ ecs->another_trap = 1;
+ keep_going (ecs);
+ return;
}
- if (stop_signal >= NSIG
- || signal_stop[stop_signal])
+#endif /* 0 */
+ disable_longjmp_breakpoint ();
+ ecs->handling_longjmp = 0; /* FIXME */
+ if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
break;
- /* If not going to stop, give terminal back
- if we took it away. */
- else if (printed)
- terminal_inferior ();
- }
-
- /* Handle cases caused by hitting a breakpoint. */
-
- if (!random_signal
- && (stop_breakpoint || stop_step_resume_break))
- {
- /* Does a breakpoint want us to stop? */
- if (stop_breakpoint && stop_breakpoint != -1
- && stop_breakpoint != -0x1000001)
+ /* else fallthrough */
+
+ case BPSTAT_WHAT_SINGLE:
+ if (breakpoints_inserted)
{
- /* 0x1000000 is set in stop_breakpoint as returned by
- breakpoint_stop_status to indicate a silent
- breakpoint. */
- if ((stop_breakpoint > 0 ? stop_breakpoint :
- -stop_breakpoint)
- & 0x1000000)
- {
- stop_print_frame = 0;
- if (stop_breakpoint > 0)
- stop_breakpoint -= 0x1000000;
- else
- stop_breakpoint += 0x1000000;
- }
- break;
+ thread_step_needed = 1;
+ remove_breakpoints ();
}
- /* 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. */
- if (stop_step_resume_break
- && (step_frame_address == 0
- || (stop_frame_address == step_frame_address)))
+ breakpoints_inserted = 0;
+ ecs->another_trap = 1;
+ /* Still need to check other stuff, at least the case
+ where we are stepping and step out of the right range. */
+ break;
+
+ case BPSTAT_WHAT_STOP_NOISY:
+ stop_print_frame = 1;
+
+ /* We are about to nuke the step_resume_breakpoint and
+ through_sigtramp_breakpoint via the cleanup chain, so
+ no need to worry about it here. */
+
+ stop_stepping (ecs);
+ return;
+
+ case BPSTAT_WHAT_STOP_SILENT:
+ stop_print_frame = 0;
+
+ /* We are about to nuke the step_resume_breakpoint and
+ through_sigtramp_breakpoint via the cleanup chain, so
+ no need to worry about it here. */
+
+ stop_stepping (ecs);
+ return;
+
+ case BPSTAT_WHAT_STEP_RESUME:
+ /* This proably demands a more elegant solution, but, yeah
+ right...
+
+ This function's use of the simple variable
+ step_resume_breakpoint doesn't seem to accomodate
+ simultaneously active step-resume bp's, although the
+ breakpoint list certainly can.
+
+ If we reach here and step_resume_breakpoint is already
+ NULL, then apparently we have multiple active
+ step-resume bp's. We'll just delete the breakpoint we
+ stopped at, and carry on.
+
+ Correction: what the code currently does is delete a
+ step-resume bp, but it makes no effort to ensure that
+ the one deleted is the one currently stopped at. MVS */
+
+ if (step_resume_breakpoint == NULL)
{
- remove_step_breakpoint ();
- step_resume_break_address = 0;
+ step_resume_breakpoint =
+ bpstat_find_step_resume_breakpoint (stop_bpstat);
}
- /* Otherwise, must remove breakpoints and single-step
- to get us past the one we hit. */
- else
- {
+ delete_breakpoint (step_resume_breakpoint);
+ step_resume_breakpoint = NULL;
+ break;
+
+ case BPSTAT_WHAT_THROUGH_SIGTRAMP:
+ if (through_sigtramp_breakpoint)
+ delete_breakpoint (through_sigtramp_breakpoint);
+ through_sigtramp_breakpoint = NULL;
+
+ /* If were waiting for a trap, hitting the step_resume_break
+ doesn't count as getting it. */
+ if (trap_expected)
+ ecs->another_trap = 1;
+ break;
+
+ case BPSTAT_WHAT_CHECK_SHLIBS:
+ case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
+#ifdef SOLIB_ADD
+ {
+ /* Remove breakpoints, we eventually want to step over the
+ shlib event breakpoint, and SOLIB_ADD might adjust
+ breakpoint addresses via breakpoint_re_set. */
+ if (breakpoints_inserted)
remove_breakpoints ();
- remove_step_breakpoint ();
- breakpoints_inserted = 0;
- 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. */
+ breakpoints_inserted = 0;
+
+ /* 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 ();
+ }
+
+ /* Try to reenable shared library breakpoints, additional
+ code segments in shared libraries might be mapped in now. */
+ re_enable_breakpoints_in_shlibs ();
+
+ /* If requested, stop when the dynamic linker notifies
+ gdb of events. This allows the user to get control
+ and place breakpoints in initializer routines for
+ dynamically loaded objects (among other things). */
+ if (stop_on_solib_events)
+ {
+ stop_stepping (ecs);
+ return;
+ }
+
+ /* If we stopped due to an explicit catchpoint, then the
+ (see above) call to SOLIB_ADD pulled in any symbols
+ from a newly-loaded library, if appropriate.
+
+ We do want the inferior to stop, but not where it is
+ now, which is in the dynamic linker callback. Rather,
+ we would like it stop in the user's program, just after
+ the call that caused this catchpoint to trigger. That
+ gives the user a more useful vantage from which to
+ examine their program's state. */
+ else if (what.main_action == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
+ {
+ /* ??rehrauer: If I could figure out how to get the
+ right return PC from here, we could just set a temp
+ breakpoint and resume. I'm not sure we can without
+ cracking open the dld's shared libraries and sniffing
+ their unwind tables and text/data ranges, and that's
+ not a terribly portable notion.
+
+ Until that time, we must step the inferior out of the
+ dld callback, and also out of the dld itself (and any
+ code or stubs in libdld.sl, such as "shl_load" and
+ friends) until we reach non-dld code. At that point,
+ we can stop stepping. */
+ bpstat_get_triggered_catchpoints (stop_bpstat,
+ &ecs->stepping_through_solib_catchpoints);
+ ecs->stepping_through_solib_after_catch = 1;
+
+ /* Be sure to lift all breakpoints, so the inferior does
+ actually step past this point... */
+ ecs->another_trap = 1;
+ break;
+ }
+ else
+ {
+ /* We want to step over this breakpoint, then keep going. */
+ ecs->another_trap = 1;
+ break;
+ }
+ }
+#endif
+ break;
+
+ case BPSTAT_WHAT_LAST:
+ /* Not a real code, but listed here to shut up gcc -Wall. */
+
+ case BPSTAT_WHAT_KEEP_CHECKING:
+ break;
}
-
- /* If this is the breakpoint at the end of a stack dummy,
- just stop silently. */
-#ifndef CANNOT_EXECUTE_STACK
- if (stop_sp INNER_THAN stop_pc
- && stop_pc INNER_THAN stop_frame_address)
-#else
- if (stop_pc == text_end - 2)
+ }
+
+ /* We come here if we hit a breakpoint but should not
+ stop for it. Possibly we also were stepping
+ and should stop for that. So fall through and
+ test for stepping. But, if not stepping,
+ do not stop. */
+
+ /* Are we stepping to get the inferior out of the dynamic
+ linker's hook (and possibly the dld itself) after catching
+ a shlib event? */
+ if (ecs->stepping_through_solib_after_catch)
+ {
+#if defined(SOLIB_ADD)
+ /* Have we reached our destination? If not, keep going. */
+ if (SOLIB_IN_DYNAMIC_LINKER (ecs->pid, stop_pc))
+ {
+ ecs->another_trap = 1;
+ keep_going (ecs);
+ return;
+ }
#endif
+ /* Else, stop and report the catchpoint(s) whose triggering
+ caused us to begin stepping. */
+ ecs->stepping_through_solib_after_catch = 0;
+ bpstat_clear (&stop_bpstat);
+ stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints);
+ bpstat_clear (&ecs->stepping_through_solib_catchpoints);
+ stop_print_frame = 1;
+ stop_stepping (ecs);
+ return;
+ }
+
+ if (!CALL_DUMMY_BREAKPOINT_OFFSET_P)
+ {
+ /* This is the old way of detecting the end of the stack dummy.
+ An architecture which defines CALL_DUMMY_BREAKPOINT_OFFSET gets
+ handled above. As soon as we can test it on all of them, all
+ architectures should define it. */
+
+ /* If this is the breakpoint at the end of a stack dummy,
+ just stop silently, unless the user was doing an si/ni, in which
+ case she'd better know what she's doing. */
+
+ if (CALL_DUMMY_HAS_COMPLETED (stop_pc, read_sp (),
+ FRAME_FP (get_current_frame ()))
+ && !step_range_end)
{
stop_print_frame = 0;
stop_stack_dummy = 1;
#ifdef HP_OS_BUG
trap_expected_after_continue = 1;
#endif
- break;
+ stop_stepping (ecs);
+ return;
}
-
- if (step_resume_break_address)
+ }
+
+ if (step_resume_breakpoint)
+ {
/* 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)))
- {
- /* Don't step through the return from a function
- unless that is the first instruction stepped through. */
- if (ABOUT_TO_RETURN (stop_pc))
- {
- stop_step = 1;
- break;
- }
- }
-
- /* 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)
+ /* I'm not sure whether this needs to be check_sigtramp2 or
+ whether it could/should be keep_going. */
+ check_sigtramp2 (ecs);
+ keep_going (ecs);
+ return;
+ }
+
+ if (step_range_end == 0)
+ {
+ /* Likewise if we aren't even stepping. */
+ /* I'm not sure whether this needs to be check_sigtramp2 or
+ whether it could/should be keep_going. */
+ check_sigtramp2 (ecs);
+ keep_going (ecs);
+ return;
+ }
+
+ /* If stepping through a line, keep going if still within it.
+
+ Note that step_range_end is the address of the first instruction
+ beyond the step range, and NOT the address of the last instruction
+ within it! */
+ if (stop_pc >= step_range_start
+ && stop_pc < step_range_end)
+ {
+ /* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal.
+ So definately need to check for sigtramp here. */
+ check_sigtramp2 (ecs);
+ keep_going (ecs);
+ return;
+ }
+
+ /* We stepped out of the stepping range. */
+
+ /* If we are stepping at the source level and entered the runtime
+ loader dynamic symbol resolution code, we keep on single stepping
+ until we exit the run time loader code and reach the callee's
+ address. */
+ if (step_over_calls < 0 && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc))
+ {
+ CORE_ADDR pc_after_resolver = SKIP_SOLIB_RESOLVER (stop_pc);
+
+ if (pc_after_resolver)
+ {
+ /* Set up a step-resume breakpoint at the address
+ indicated by SKIP_SOLIB_RESOLVER. */
+ struct symtab_and_line sr_sal;
+ INIT_SAL (&sr_sal);
+ sr_sal.pc = pc_after_resolver;
+
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+ }
+
+ keep_going (ecs);
+ return;
+ }
+
+ /* We can't update step_sp every time through the loop, because
+ reading the stack pointer would slow down stepping too much.
+ But we can update it every time we leave the step range. */
+ ecs->update_step_sp = 1;
+
+ /* Did we just take a signal? */
+ if (IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
+ && !IN_SIGTRAMP (prev_pc, prev_func_name)
+ && INNER_THAN (read_sp (), step_sp))
+ {
+ /* We've just taken a signal; go until we are back to
+ the point where we took it and one more. */
+
+ /* Note: The test above succeeds not only when we stepped
+ into a signal handler, but also when we step past the last
+ statement of a signal handler and end up in the return stub
+ of the signal handler trampoline. To distinguish between
+ these two cases, check that the frame is INNER_THAN the
+ previous one below. pai/1997-09-11 */
+
+
{
- if (stop_func_start)
- {
- prologue_pc = stop_func_start;
- SKIP_PROLOGUE (prologue_pc);
- }
+ CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
- /* Did we just take a signal? */
- if (IN_SIGTRAMP (stop_pc, stop_func_name)
- && !IN_SIGTRAMP (prev_pc, prev_func_name))
+ if (INNER_THAN (current_frame, step_frame_address))
{
+ /* We have just taken a signal; go until we are back to
+ the point where we took it and one more. */
+
/* This code is needed at least in the following case:
- The user types "next" and then a signal arrives (before
- the "next" is done). */
- /* 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);
- step_resume_break_sp = stop_sp;
+ The user types "next" and then a signal arrives (before
+ the "next" is done). */
+
+ /* Note that if we are stopped at a breakpoint, then we need
+ the step_resume breakpoint to override any breakpoints at
+ the same location, so that we will still step over the
+ breakpoint even though the signal happened. */
+ struct symtab_and_line sr_sal;
+
+ INIT_SAL (&sr_sal);
+ sr_sal.symtab = NULL;
+ sr_sal.line = 0;
+ sr_sal.pc = prev_pc;
+ /* We could probably be setting the frame to
+ step_frame_address; I don't think anyone thought to
+ try it. */
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
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;
- }
-
- /* ==> See comments at top of file on this algorithm. <==*/
-
- else if (stop_pc == stop_func_start
- && (stop_func_start != prev_func_start
- || prologue_pc != stop_func_start
- || stop_sp != prev_sp))
- {
- /* It's a subroutine call */
- if (step_over_calls > 0
- || (step_over_calls && find_pc_function (stop_pc) == 0))
- {
- /* A subroutine call has happened. */
- /* Set a special breakpoint after the return */
- step_resume_break_address =
- SAVED_PC_AFTER_CALL (get_current_frame ());
- step_resume_break_duplicate
- = breakpoint_here_p (step_resume_break_address);
- step_resume_break_sp = stop_sp;
- if (breakpoints_inserted)
- insert_step_breakpoint ();
- }
- /* Subroutine call with source code we should not step over.
- Do step to the first line of code in it. */
- else if (step_over_calls)
- {
- 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_sp = stop_sp;
-
- 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;
- }
- }
- else
- {
- /* We get here only if step_over_calls is 0 and we
- just stepped into a subroutine. 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;
- }
+ insert_breakpoints ();
}
- /* No subroutince call; stop now. */
else
{
- stop_step = 1;
- break;
+ /* We just stepped out of a signal handler and into
+ its calling trampoline.
+
+ Normally, we'd call step_over_function from
+ here, but for some reason GDB can't unwind the
+ stack correctly to find the real PC for the point
+ user code where the signal trampoline will return
+ -- FRAME_SAVED_PC fails, at least on HP-UX 10.20.
+ But signal trampolines are pretty small stubs of
+ code, anyway, so it's OK instead to just
+ single-step out. Note: assuming such trampolines
+ don't exhibit recursion on any platform... */
+ find_pc_partial_function (stop_pc, &ecs->stop_func_name,
+ &ecs->stop_func_start,
+ &ecs->stop_func_end);
+ /* Readjust stepping range */
+ step_range_start = ecs->stop_func_start;
+ step_range_end = ecs->stop_func_end;
+ ecs->stepping_through_sigtramp = 1;
}
}
- /* 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 is 2, it means continue once more
- and insert breakpoints at the next trap.
- If trap_expected is 1 and the signal was SIGSEGV, it means
- the shell is doing some memory allocation--just resume it
- with SIGSEGV.
- Otherwise insert breakpoints now, and possibly single step. */
-
- if (trap_expected > 1)
+
+ /* If this is stepi or nexti, make sure that the stepping range
+ gets us past that instruction. */
+ if (step_range_end == 1)
+ /* FIXME: Does this run afoul of the code below which, if
+ we step into the middle of a line, resets the stepping
+ range? */
+ step_range_end = (step_range_start = prev_pc) + 1;
+
+ ecs->remove_breakpoints_on_following_step = 1;
+ keep_going (ecs);
+ return;
+ }
+
+ if (stop_pc == ecs->stop_func_start /* Quick test */
+ || (in_prologue (stop_pc, ecs->stop_func_start) &&
+ !IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
+ || IN_SOLIB_CALL_TRAMPOLINE (stop_pc, ecs->stop_func_name)
+ || ecs->stop_func_name == 0)
+ {
+ /* It's a subroutine call. */
+
+ 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
+ ("stepi"). Just stop. */
+ stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
+ }
+
+ if (step_over_calls > 0 || IGNORE_HELPER_CALL (stop_pc))
+ {
+ /* We're doing a "next". */
+ step_over_function (ecs);
+ keep_going (ecs);
+ return;
+ }
+
+ /* If we are in a function call trampoline (a stub between
+ the calling routine and the real function), locate the real
+ function. That's what tells us (a) whether we want to step
+ into it at all, and (b) what prologue we want to run to
+ the end of, if we do step into it. */
+ tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
+ if (tmp != 0)
+ ecs->stop_func_start = tmp;
+ else
+ {
+ tmp = DYNAMIC_TRAMPOLINE_NEXTPC (stop_pc);
+ if (tmp)
+ {
+ struct symtab_and_line xxx;
+ /* 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);
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (xxx, NULL, bp_step_resume);
+ insert_breakpoints ();
+ keep_going (ecs);
+ return;
+ }
+ }
+
+ /* If we have line number information for the function we
+ are thinking of stepping into, step into it.
+
+ If there are several symtabs at that PC (e.g. with include
+ files), just want to know whether *any* of them have line
+ numbers. find_pc_line handles this. */
{
- trap_expected--;
- running_in_shell = 1;
- resume (0, 0);
+ struct symtab_and_line tmp_sal;
+
+ tmp_sal = find_pc_line (ecs->stop_func_start, 0);
+ if (tmp_sal.line != 0)
+ {
+ step_into_function (ecs);
+ return;
+ }
}
- else if (running_in_shell && stop_signal == SIGSEGV)
+ step_over_function (ecs);
+ keep_going (ecs);
+ return;
+
+ }
+
+ /* We've wandered out of the step range. */
+
+ ecs->sal = find_pc_line (stop_pc, 0);
+
+ if (step_range_end == 1)
+ {
+ /* It is stepi or nexti. We always want to stop stepping after
+ one instruction. */
+ stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
+ }
+
+ /* If we're in the return path from a shared library trampoline,
+ we want to proceed through the trampoline when stepping. */
+ if (IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
+ {
+ CORE_ADDR tmp;
+
+ /* Determine where this trampoline returns. */
+ tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
+
+ /* Only proceed through if we know where it's going. */
+ if (tmp)
+ {
+ /* And put the step-breakpoint there and go until there. */
+ struct symtab_and_line sr_sal;
+
+ INIT_SAL (&sr_sal); /* initialize to zeroes */
+ sr_sal.pc = 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. */
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+
+ /* Restart without fiddling with the step ranges or
+ other state. */
+ keep_going (ecs);
+ return;
+ }
+ }
+
+ if (ecs->sal.line == 0)
+ {
+ /* We have no line number information. That means to stop
+ stepping (does this always happen right after one instruction,
+ when we do "s" in a function with no line numbers,
+ or can this happen as a result of a return or longjmp?). */
+ stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
+ }
+
+ if ((stop_pc == ecs->sal.pc)
+ && (ecs->current_line != ecs->sal.line || ecs->current_symtab != ecs->sal.symtab))
+ {
+ /* We are at the start of a different line. So stop. Note that
+ we don't stop if we step into the middle of a different line.
+ That is said to make things like for (;;) statements work
+ better. */
+ stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
+ }
+
+ /* We aren't done stepping.
+
+ Optimize by setting the stepping range to the line.
+ (We might not be in the original line, but if we entered a
+ new line in mid-statement, we continue stepping. This makes
+ things like for(;;) statements work better.) */
+
+ if (ecs->stop_func_end && ecs->sal.end >= ecs->stop_func_end)
+ {
+ /* If this is the last line of the function, don't keep stepping
+ (it would probably step us out of the function).
+ This is particularly necessary for a one-line function,
+ in which after skipping the prologue we better stop even though
+ we will be in mid-line. */
+ stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
+ }
+ step_range_start = ecs->sal.pc;
+ step_range_end = ecs->sal.end;
+ step_frame_address = FRAME_FP (get_current_frame ());
+ ecs->current_line = ecs->sal.line;
+ ecs->current_symtab = ecs->sal.symtab;
+
+ /* In the case where we just stepped out of a function into the middle
+ of a line of the caller, continue stepping, but step_frame_address
+ must be modified to current frame */
+ {
+ CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
+ if (!(INNER_THAN (current_frame, step_frame_address)))
+ step_frame_address = current_frame;
+ }
+
+ keep_going (ecs);
+
+ } /* extra brace, to preserve old indentation */
+}
+
+/* Are we in the middle of stepping? */
+
+static int
+currently_stepping (struct execution_control_state *ecs)
+{
+ return ((through_sigtramp_breakpoint == NULL
+ && !ecs->handling_longjmp
+ && ((step_range_end && step_resume_breakpoint == NULL)
+ || trap_expected))
+ || ecs->stepping_through_solib_after_catch
+ || bpstat_should_step ());
+}
+
+static void
+check_sigtramp2 (struct execution_control_state *ecs)
+{
+ if (trap_expected
+ && IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
+ && !IN_SIGTRAMP (prev_pc, prev_func_name)
+ && INNER_THAN (read_sp (), step_sp))
+ {
+ /* What has happened here is that we have just stepped the
+ inferior with a signal (because it is a signal which
+ shouldn't make us stop), thus stepping into sigtramp.
+
+ So we need to set a step_resume_break_address breakpoint and
+ continue until we hit it, and then step. FIXME: This should
+ be more enduring than a step_resume breakpoint; we should
+ know that we will later need to keep going rather than
+ re-hitting the breakpoint here (see the testsuite,
+ gdb.base/signals.exp where it says "exceedingly difficult"). */
+
+ struct symtab_and_line sr_sal;
+
+ INIT_SAL (&sr_sal); /* initialize to zeroes */
+ sr_sal.pc = prev_pc;
+ sr_sal.section = find_pc_overlay (sr_sal.pc);
+ /* We perhaps could set the frame if we kept track of what the
+ frame corresponding to prev_pc was. But we don't, so don't. */
+ through_sigtramp_breakpoint =
+ set_momentary_breakpoint (sr_sal, NULL, bp_through_sigtramp);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+
+ ecs->remove_breakpoints_on_following_step = 1;
+ ecs->another_trap = 1;
+ }
+}
+
+/* Subroutine call with source code we should not step over. Do step
+ to the first line of code in it. */
+
+static void
+step_into_function (struct execution_control_state *ecs)
+{
+ struct symtab *s;
+ struct symtab_and_line sr_sal;
+
+ s = find_pc_symtab (stop_pc);
+ if (s && s->language != language_asm)
+ ecs->stop_func_start = SKIP_PROLOGUE (ecs->stop_func_start);
+
+ ecs->sal = find_pc_line (ecs->stop_func_start, 0);
+ /* Use the step_resume_break to step until the end of the prologue,
+ even if that involves jumps (as it seems to on the vax under
+ 4.2). */
+ /* If the prologue ends in the middle of a source line, continue to
+ the end of that source line (if it is still within the function).
+ Otherwise, just go to end of prologue. */
+#ifdef PROLOGUE_FIRSTLINE_OVERLAP
+ /* no, don't either. It skips any code that's legitimately on the
+ first line. */
+#else
+ if (ecs->sal.end
+ && ecs->sal.pc != ecs->stop_func_start
+ && ecs->sal.end < ecs->stop_func_end)
+ ecs->stop_func_start = ecs->sal.end;
+#endif
+
+ if (ecs->stop_func_start == stop_pc)
+ {
+ /* We are already there: stop now. */
+ stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
+ }
+ else
+ {
+ /* Put the step-breakpoint there and go until there. */
+ INIT_SAL (&sr_sal); /* initialize to zeroes */
+ sr_sal.pc = ecs->stop_func_start;
+ sr_sal.section = find_pc_overlay (ecs->stop_func_start);
+ /* Do not specify what the fp should be when we stop since on
+ some machines the prologue is where the new fp value is
+ established. */
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+
+ /* And make sure stepping stops right away then. */
+ step_range_end = step_range_start;
+ }
+ keep_going (ecs);
+}
+
+/* We've just entered a callee, and we wish to resume until it returns
+ to the caller. Setting a step_resume breakpoint on the return
+ address will catch a return from the callee.
+
+ However, if the callee is recursing, we want to be careful not to
+ catch returns of those recursive calls, but only of THIS instance
+ of the call.
+
+ To do this, we set the step_resume bp's frame to our current
+ caller's frame (step_frame_address, which is set by the "next" or
+ "until" command, before execution begins). */
+
+static void
+step_over_function (struct execution_control_state *ecs)
+{
+ struct symtab_and_line sr_sal;
+
+ INIT_SAL (&sr_sal); /* initialize to zeros */
+ sr_sal.pc = ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ()));
+ sr_sal.section = find_pc_overlay (sr_sal.pc);
+
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, get_current_frame (), bp_step_resume);
+
+ if (!IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
+ step_resume_breakpoint->frame = step_frame_address;
+
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+}
+
+static void
+stop_stepping (struct execution_control_state *ecs)
+{
+ if (target_has_execution)
+ {
+ /* Are we stopping for a vfork event? We only stop when we see
+ the child's event. However, we may not yet have seen the
+ parent's event. And, inferior_pid is still set to the
+ parent's pid, until we resume again and follow either the
+ parent or child.
+
+ To ensure that we can really touch inferior_pid (aka, the
+ parent process) -- which calls to functions like read_pc
+ implicitly do -- wait on the parent if necessary. */
+ if ((pending_follow.kind == TARGET_WAITKIND_VFORKED)
+ && !pending_follow.fork_event.saw_parent_fork)
{
- resume (0, SIGSEGV);
+ int parent_pid;
+
+ do
+ {
+ if (target_wait_hook)
+ parent_pid = target_wait_hook (-1, &(ecs->ws));
+ else
+ parent_pid = target_wait (-1, &(ecs->ws));
+ }
+ while (parent_pid != inferior_pid);
}
- else if (trap_expected && stop_signal != SIGTRAP)
+
+ /* 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 = ecs->stop_func_start;
+ prev_func_name = ecs->stop_func_name;
+ }
+
+ /* Let callers know we don't want to wait for the inferior anymore. */
+ ecs->wait_some_more = 0;
+}
+
+/* This function handles various cases where we need to continue
+ waiting for the inferior. */
+/* (Used to be the keep_going: label in the old wait_for_inferior) */
+
+static void
+keep_going (struct execution_control_state *ecs)
+{
+ /* ??rehrauer: ttrace on HP-UX theoretically allows one to debug a
+ vforked child between its creation and subsequent exit or call to
+ exec(). However, I had big problems in this rather creaky exec
+ engine, getting that to work. The fundamental problem is that
+ I'm trying to debug two processes via an engine that only
+ understands a single process with possibly multiple threads.
+
+ Hence, this spot is known to have problems when
+ target_can_follow_vfork_prior_to_exec returns 1. */
+
+ /* Save the pc before execution, to compare with pc after stop. */
+ prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
+ prev_func_start = ecs->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 = ecs->stop_func_name;
+
+ if (ecs->update_step_sp)
+ step_sp = read_sp ();
+ ecs->update_step_sp = 0;
+
+ /* If we did not do break;, it means we should keep running the
+ inferior and not return to debugger. */
+
+ if (trap_expected && stop_signal != TARGET_SIGNAL_TRAP)
+ {
+ /* We took a signal (which we are supposed to pass through to
+ the inferior, else we'd have done a break above) and we
+ haven't yet gotten our trap. Simply continue. */
+ resume (currently_stepping (ecs), stop_signal);
+ }
+ else
+ {
+ /* Either the trap was not expected, but we are continuing
+ anyway (the user asked that this signal be passed to the
+ child)
+ -- or --
+ The signal was SIGTRAP, e.g. it was our signal, but we
+ decided we should resume from it.
+
+ We're going to run this baby now!
+
+ Insert breakpoints now, unless we are trying to one-proceed
+ past a breakpoint. */
+ /* If we've just finished a special step resume and we don't
+ want to hit a breakpoint, pull em out. */
+ if (step_resume_breakpoint == NULL
+ && through_sigtramp_breakpoint == NULL
+ && ecs->remove_breakpoints_on_following_step)
{
- /* We took a signal which we are supposed to pass through to
- the inferior and we haven't yet gotten our trap. Simply
- continue. */
- resume ((step_range_end && !step_resume_break_address)
- || trap_expected,
- stop_signal);
+ ecs->remove_breakpoints_on_following_step = 0;
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
}
- else
+ else if (!breakpoints_inserted &&
+ (through_sigtramp_breakpoint != NULL || !ecs->another_trap))
{
- /* Here, we are not awaiting another exec to get
- the program we really want to debug.
- Insert breakpoints now, unless we are trying
- to one-proceed past a breakpoint. */
- running_in_shell = 0;
- /* 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 && !another_trap)
+ breakpoints_failed = insert_breakpoints ();
+ if (breakpoints_failed)
{
- insert_step_breakpoint ();
- breakpoints_failed = insert_breakpoints ();
- if (breakpoints_failed)
- break;
- breakpoints_inserted = 1;
+ stop_stepping (ecs);
+ return;
}
+ breakpoints_inserted = 1;
+ }
+
+ trap_expected = ecs->another_trap;
+
+ /* Do not deliver SIGNAL_TRAP (except when the user explicitly
+ specifies that such a signal should be delivered to the
+ target program).
+
+ Typically, this would occure when a user is debugging a
+ target monitor on a simulator: the target monitor sets a
+ breakpoint; the simulator encounters this break-point and
+ halts the simulation handing control to GDB; GDB, noteing
+ that the break-point isn't valid, returns control back to the
+ simulator; the simulator then delivers the hardware
+ equivalent of a SIGNAL_TRAP to the program being debugged. */
+
+ if (stop_signal == TARGET_SIGNAL_TRAP
+ && !signal_program[stop_signal])
+ stop_signal = TARGET_SIGNAL_0;
+
+#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. */
+ /* FIXME: Shouldn't this be based on the valid bit of the SXIP?
+ (this is only used on the 88k). */
+
+ if (!bpstat_explains_signal (stop_bpstat)
+ && (stop_signal != TARGET_SIGNAL_CHLD)
+ && !stopped_by_random_signal)
+ SHIFT_INST_REGS ();
+#endif /* SHIFT_INST_REGS */
+
+ resume (currently_stepping (ecs), stop_signal);
+ }
+
+ prepare_to_wait (ecs);
+}
+
+/* This function normally comes after a resume, before
+ handle_inferior_event exits. It takes care of any last bits of
+ housekeeping, and sets the all-important wait_some_more flag. */
- trap_expected = another_trap;
+static void
+prepare_to_wait (struct execution_control_state *ecs)
+{
+ if (ecs->infwait_state == infwait_normal_state)
+ {
+ overlay_cache_invalid = 1;
+
+ /* We have to invalidate the registers BEFORE calling
+ target_wait because they can be loaded from the target while
+ in target_wait. This makes remote debugging a bit more
+ efficient for those targets that provide critical registers
+ as part of their normal status mechanism. */
- if (stop_signal == SIGTRAP)
- stop_signal = 0;
+ registers_changed ();
+ ecs->waiton_pid = -1;
+ ecs->wp = &(ecs->ws);
+ }
+ /* This is the old end of the while loop. Let everybody know we
+ want to wait for the inferior some more and get called again
+ soon. */
+ ecs->wait_some_more = 1;
+}
- resume ((step_range_end && !step_resume_break_address)
- || trap_expected,
- stop_signal);
+/* Print why the inferior has stopped. We always print something when
+ the inferior exits, or receives a signal. The rest of the cases are
+ dealt with later on in normal_stop() and print_it_typical(). Ideally
+ there should be a call to this function from handle_inferior_event()
+ each time stop_stepping() is called.*/
+static void
+print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
+{
+ switch (stop_reason)
+ {
+ case STOP_UNKNOWN:
+ /* We don't deal with these cases from handle_inferior_event()
+ yet. */
+ break;
+ case END_STEPPING_RANGE:
+ /* We are done with a step/next/si/ni command. */
+ /* For now print nothing. */
+#ifdef UI_OUT
+ /* Print a message only if not in the middle of doing a "step n"
+ operation for n > 1 */
+ if (!step_multi || !stop_step)
+ if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ ui_out_field_string (uiout, "reason", "end-stepping-range");
+#endif
+ break;
+ case BREAKPOINT_HIT:
+ /* We found a breakpoint. */
+ /* For now print nothing. */
+ break;
+ case SIGNAL_EXITED:
+ /* The inferior was terminated by a signal. */
+#ifdef UI_OUT
+ annotate_signalled ();
+ if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ ui_out_field_string (uiout, "reason", "exited-signalled");
+ ui_out_text (uiout, "\nProgram terminated with signal ");
+ annotate_signal_name ();
+ ui_out_field_string (uiout, "signal-name", target_signal_to_name (stop_info));
+ annotate_signal_name_end ();
+ ui_out_text (uiout, ", ");
+ annotate_signal_string ();
+ ui_out_field_string (uiout, "signal-meaning", target_signal_to_string (stop_info));
+ annotate_signal_string_end ();
+ ui_out_text (uiout, ".\n");
+ ui_out_text (uiout, "The program no longer exists.\n");
+#else
+ annotate_signalled ();
+ printf_filtered ("\nProgram terminated with signal ");
+ annotate_signal_name ();
+ printf_filtered ("%s", target_signal_to_name (stop_info));
+ annotate_signal_name_end ();
+ printf_filtered (", ");
+ annotate_signal_string ();
+ printf_filtered ("%s", target_signal_to_string (stop_info));
+ annotate_signal_string_end ();
+ printf_filtered (".\n");
+
+ printf_filtered ("The program no longer exists.\n");
+ gdb_flush (gdb_stdout);
+#endif
+ break;
+ case EXITED:
+ /* The inferior program is finished. */
+#ifdef UI_OUT
+ annotate_exited (stop_info);
+ if (stop_info)
+ {
+ if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ ui_out_field_string (uiout, "reason", "exited");
+ ui_out_text (uiout, "\nProgram exited with code ");
+ ui_out_field_fmt (uiout, "exit-code", "0%o", (unsigned int) stop_info);
+ ui_out_text (uiout, ".\n");
+ }
+ else
+ {
+ if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ ui_out_field_string (uiout, "reason", "exited-normally");
+ ui_out_text (uiout, "\nProgram exited normally.\n");
}
+#else
+ annotate_exited (stop_info);
+ if (stop_info)
+ printf_filtered ("\nProgram exited with code 0%o.\n",
+ (unsigned int) stop_info);
+ else
+ printf_filtered ("\nProgram exited normally.\n");
+#endif
+ break;
+ case SIGNAL_RECEIVED:
+ /* Signal received. The signal table tells us to print about
+ it. */
+#ifdef UI_OUT
+ annotate_signal ();
+ ui_out_text (uiout, "\nProgram received signal ");
+ annotate_signal_name ();
+ ui_out_field_string (uiout, "signal-name", target_signal_to_name (stop_info));
+ annotate_signal_name_end ();
+ ui_out_text (uiout, ", ");
+ annotate_signal_string ();
+ ui_out_field_string (uiout, "signal-meaning", target_signal_to_string (stop_info));
+ annotate_signal_string_end ();
+ ui_out_text (uiout, ".\n");
+#else
+ annotate_signal ();
+ printf_filtered ("\nProgram received signal ");
+ annotate_signal_name ();
+ printf_filtered ("%s", target_signal_to_name (stop_info));
+ annotate_signal_name_end ();
+ printf_filtered (", ");
+ annotate_signal_string ();
+ printf_filtered ("%s", target_signal_to_string (stop_info));
+ annotate_signal_string_end ();
+ printf_filtered (".\n");
+ gdb_flush (gdb_stdout);
+#endif
+ break;
+ default:
+ internal_error ("print_stop_reason: unrecognized enum value");
+ break;
}
}
\f
+
/* Here to return control to GDB when the inferior stops for real.
Print appropriate messages, remove breakpoints, give terminal our modes.
- RUNNING_IN_SHELL nonzero means the shell got a signal before
- exec'ing the program we wanted to run.
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. */
-static void
-normal_stop ()
+void
+normal_stop (void)
{
+ /* As with the notification of thread events, we want to delay
+ notifying the user that we've switched thread context until
+ the inferior actually stops.
+
+ (Note that there's no point in saying anything if the inferior
+ has exited!) */
+ if ((previous_inferior_pid != inferior_pid)
+ && target_has_execution)
+ {
+ target_terminal_ours_for_output ();
+ printf_filtered ("[Switching to %s]\n",
+ target_pid_or_tid_to_str (inferior_pid));
+ previous_inferior_pid = inferior_pid;
+ }
+
/* 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 (inferior_pid)
+ if (target_has_execution && get_current_frame ())
(get_current_frame ())->pc = read_pc ();
-
+
if (breakpoints_failed)
{
- terminal_ours_for_output ();
+ target_terminal_ours_for_output ();
print_sys_errmsg ("ptrace", breakpoints_failed);
- printf ("Stopped; cannot insert breakpoints.\n\
+ printf_filtered ("Stopped; cannot insert breakpoints.\n\
The same program may be running in another process.\n");
}
- if (inferior_pid)
- remove_step_breakpoint ();
-
- if (inferior_pid && breakpoints_inserted)
- if (remove_breakpoints ())
- {
- terminal_ours_for_output ();
- printf ("Cannot remove breakpoints because program is no longer writable.\n\
-It must be running in another process.\n\
-Further execution is probably impossible.\n");
- }
-
+ if (target_has_execution && breakpoints_inserted)
+ {
+ if (remove_breakpoints ())
+ {
+ target_terminal_ours_for_output ();
+ printf_filtered ("Cannot remove breakpoints because ");
+ printf_filtered ("program is no longer writable.\n");
+ printf_filtered ("It might be running in another process.\n");
+ printf_filtered ("Further execution is probably impossible.\n");
+ }
+ }
breakpoints_inserted = 0;
/* Delete the breakpoint we stopped at, if it wants to be deleted.
Delete any breakpoint that is to be deleted at the next stop. */
- breakpoint_auto_delete (stop_breakpoint);
+ breakpoint_auto_delete (stop_bpstat);
/* If an auto-display called a function and that got a signal,
delete that auto-display to avoid an infinite recursion. */
if (stopped_by_random_signal)
disable_current_display ();
+ /* Don't print a message if in the middle of doing a "step n"
+ operation for n > 1 */
if (step_multi && stop_step)
- return;
+ goto done;
+
+ target_terminal_ours ();
- terminal_ours ();
+ /* Look up the hook_stop and run it if it exists. */
- if (running_in_shell)
+ if (stop_command && stop_command->hook)
{
- if (stop_signal == SIGSEGV)
- {
- char *exec_file = (char *) get_exec_file (1);
+ catch_errors (hook_stop_stub, stop_command->hook,
+ "Error while running hook_stop:\n", RETURN_MASK_ALL);
+ }
- if (access (exec_file, X_OK) != 0)
- printf ("The file \"%s\" is not executable.\n", exec_file);
- else
- /* I don't think we should ever get here.
- wait_for_inferior now ignores SIGSEGV's which happen in
- the shell (since the Bourne shell (/bin/sh) has some
- rather, er, uh, *unorthodox* memory management
- involving catching SIGSEGV). */
- printf ("\
-You have just encountered a bug in \"sh\". GDB starts your program\n\
-by running \"sh\" with a command to exec your program.\n\
-This is so that \"sh\" will process wildcards and I/O redirection.\n\
-This time, \"sh\" crashed.\n\
-\n\
-One known bug in \"sh\" bites when the environment takes up a lot of space.\n\
-Try \"info env\" to see the environment; then use \"delete env\" to kill\n\
-some variables whose values are large; then do \"run\" again.\n\
-\n\
-If that works, you might want to put those \"delete env\" commands\n\
-into a \".gdbinit\" file in this directory so they will happen every time.\n");
- }
- /* Don't confuse user with his program's symbols on sh's data. */
- stop_print_frame = 0;
+ if (!target_has_stack)
+ {
+
+ goto done;
}
- if (inferior_pid == 0)
- return;
+ /* Select innermost stack frame - i.e., current frame is frame 0,
+ and current location is based on that.
+ Don't do this on return from a stack dummy routine,
+ or if the program has exited. */
- /* Select innermost stack frame except on return from a stack dummy routine,
- or if the program has exited. */
if (!stop_stack_dummy)
{
select_frame (get_current_frame (), 0);
- if (stop_print_frame)
+ /* Print current location without a level number, if
+ we have changed functions or hit a breakpoint.
+ Print source line if we have one.
+ bpstat_print() contains the logic deciding in detail
+ what to print, based on the event(s) that just occurred. */
+
+ if (stop_print_frame
+ && selected_frame)
{
- if (stop_breakpoint > 0)
- printf ("\nBpt %d, ", stop_breakpoint);
- print_sel_frame (stop_step
- && step_frame_address == stop_frame_address
- && step_start_function == find_pc_function (stop_pc));
+ int bpstat_ret;
+ int source_flag;
+ int do_frame_printing = 1;
+
+ bpstat_ret = bpstat_print (stop_bpstat);
+ switch (bpstat_ret)
+ {
+ case PRINT_UNKNOWN:
+ if (stop_step
+ && step_frame_address == FRAME_FP (get_current_frame ())
+ && step_start_function == find_pc_function (stop_pc))
+ source_flag = SRC_LINE; /* finished step, just print source line */
+ else
+ source_flag = SRC_AND_LOC; /* print location and source line */
+ break;
+ case PRINT_SRC_AND_LOC:
+ source_flag = SRC_AND_LOC; /* print location and source line */
+ break;
+ case PRINT_SRC_ONLY:
+ source_flag = SRC_LINE;
+ break;
+ case PRINT_NOTHING:
+ do_frame_printing = 0;
+ break;
+ default:
+ internal_error ("Unknown value.");
+ }
+#ifdef UI_OUT
+ /* For mi, have the same behavior every time we stop:
+ print everything but the source line. */
+ if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ source_flag = LOC_AND_ADDRESS;
+#endif
+
+#ifdef UI_OUT
+ if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ ui_out_field_int (uiout, "thread-id", pid_to_thread_id (inferior_pid));
+#endif
+ /* The behavior of this routine with respect to the source
+ flag is:
+ SRC_LINE: Print only source line
+ LOCATION: Print only location
+ SRC_AND_LOC: Print location and source line */
+ if (do_frame_printing)
+ show_and_print_stack_frame (selected_frame, -1, source_flag);
+
/* Display the auto-display expressions. */
do_displays ();
}
}
- /* Save the function value return registers
+ /* Save the function value return registers, if we care.
We might be about to restore their previous contents. */
- read_register_bytes (0, stop_registers, REGISTER_BYTES);
+ 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. */
+ can use that next. */
POP_FRAME;
+ /* Set stop_pc to what it was before we called the function.
+ Can't rely on restore_inferior_status because that only gets
+ called if we don't stop in the called function. */
+ stop_pc = read_pc ();
select_frame (get_current_frame (), 0);
}
+
+
+ TUIDO (((TuiOpaqueFuncPtr) tui_vCheckDataValues, selected_frame));
+
+done:
+ annotate_stopped ();
+}
+
+static int
+hook_stop_stub (void *cmd)
+{
+ execute_user_command ((struct cmd_list_element *) cmd, 0);
+ return (0);
}
\f
+int
+signal_stop_state (int signo)
+{
+ return signal_stop[signo];
+}
+
+int
+signal_print_state (int signo)
+{
+ return signal_print[signo];
+}
+
+int
+signal_pass_state (int signo)
+{
+ return signal_program[signo];
+}
+
+int signal_stop_update (signo, state)
+ int signo;
+ int state;
+{
+ int ret = signal_stop[signo];
+ signal_stop[signo] = state;
+ return ret;
+}
+
+int signal_print_update (signo, state)
+ int signo;
+ int state;
+{
+ int ret = signal_print[signo];
+ signal_print[signo] = state;
+ return ret;
+}
+
+int signal_pass_update (signo, state)
+ int signo;
+ int state;
+{
+ int ret = signal_program[signo];
+ signal_program[signo] = state;
+ return ret;
+}
+
static void
-insert_step_breakpoint ()
+sig_print_header (void)
{
- if (step_resume_break_address && !step_resume_break_duplicate)
- {
- read_memory (step_resume_break_address,
- step_resume_break_shadow, sizeof break_insn);
- write_memory (step_resume_break_address,
- break_insn, sizeof break_insn);
- }
+ printf_filtered ("\
+Signal Stop\tPrint\tPass to program\tDescription\n");
}
static void
-remove_step_breakpoint ()
+sig_print_info (enum target_signal oursig)
{
- if (step_resume_break_address && !step_resume_break_duplicate)
- write_memory (step_resume_break_address, step_resume_break_shadow,
- sizeof break_insn);
+ char *name = target_signal_to_name (oursig);
+ int name_padding = 13 - strlen (name);
+
+ if (name_padding <= 0)
+ name_padding = 0;
+
+ printf_filtered ("%s", name);
+ printf_filtered ("%*.*s ", name_padding, name_padding,
+ " ");
+ printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
+ printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
+ printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
+ printf_filtered ("%s\n", target_signal_to_string (oursig));
}
-\f
+
/* Specify how various signals in the inferior should be handled. */
static void
-handle_command (args, from_tty)
- char *args;
- int from_tty;
+handle_command (char *args, int from_tty)
{
- register char *p = args;
- int signum = 0;
- register int digits, wordlen;
+ char **argv;
+ int digits, wordlen;
+ int sigfirst, signum, siglast;
+ enum target_signal oursig;
+ int allsigs;
+ int nsigs;
+ unsigned char *sigs;
+ struct cleanup *old_chain;
+
+ if (args == NULL)
+ {
+ error_no_arg ("signal to handle");
+ }
+
+ /* Allocate and zero an array of flags for which signals to handle. */
+
+ nsigs = (int) TARGET_SIGNAL_LAST;
+ sigs = (unsigned char *) alloca (nsigs);
+ memset (sigs, 0, nsigs);
+
+ /* Break the command line up into args. */
- if (!args)
- error_no_arg ("signal to handle");
+ argv = buildargv (args);
+ if (argv == NULL)
+ {
+ nomem (0);
+ }
+ old_chain = make_cleanup_freeargv (argv);
- while (*p)
+ /* Walk through the args, looking for signal oursigs, signal names, and
+ actions. Signal numbers and signal names may be interspersed with
+ actions, with the actions being performed for all signals cumulatively
+ specified. Signal ranges can be specified as <LOW>-<HIGH>. */
+
+ while (*argv != NULL)
{
- /* Find the end of the next word in the args. */
- for (wordlen = 0; p[wordlen] && p[wordlen] != ' ' && p[wordlen] != '\t';
- wordlen++);
- for (digits = 0; p[digits] >= '0' && p[digits] <= '9'; digits++);
+ wordlen = strlen (*argv);
+ for (digits = 0; isdigit ((*argv)[digits]); digits++)
+ {;
+ }
+ allsigs = 0;
+ sigfirst = siglast = -1;
- /* If it is all digits, it is signal number to operate on. */
- if (digits == wordlen)
+ if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
+ {
+ /* Apply action to all signals except those used by the
+ debugger. Silently skip those. */
+ allsigs = 1;
+ sigfirst = 0;
+ siglast = nsigs - 1;
+ }
+ else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
+ {
+ SET_SIGS (nsigs, sigs, signal_stop);
+ SET_SIGS (nsigs, sigs, signal_print);
+ }
+ else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
+ {
+ UNSET_SIGS (nsigs, sigs, signal_program);
+ }
+ else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
+ {
+ SET_SIGS (nsigs, sigs, signal_print);
+ }
+ else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
{
- signum = atoi (p);
- if (signum <= 0 || signum >= NSIG)
+ SET_SIGS (nsigs, sigs, signal_program);
+ }
+ else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
+ {
+ UNSET_SIGS (nsigs, sigs, signal_stop);
+ }
+ else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
+ {
+ SET_SIGS (nsigs, sigs, signal_program);
+ }
+ else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
+ {
+ UNSET_SIGS (nsigs, sigs, signal_print);
+ UNSET_SIGS (nsigs, sigs, signal_stop);
+ }
+ else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
+ {
+ UNSET_SIGS (nsigs, sigs, signal_program);
+ }
+ else if (digits > 0)
+ {
+ /* It is numeric. The numeric signal refers to our own
+ internal signal numbering from target.h, not to host/target
+ signal number. This is a feature; users really should be
+ using symbolic names anyway, and the common ones like
+ SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
+
+ sigfirst = siglast = (int)
+ target_signal_from_command (atoi (*argv));
+ if ((*argv)[digits] == '-')
{
- p[wordlen] = '\0';
- error ("Invalid signal %s given as argument to \"handle\".", p);
+ siglast = (int)
+ target_signal_from_command (atoi ((*argv) + digits + 1));
}
- if (signum == SIGTRAP || signum == SIGINT)
+ if (sigfirst > siglast)
{
- if (!query ("Signal %d is used by the debugger.\nAre you sure you want to change it? ", signum))
- error ("Not confirmed.");
+ /* Bet he didn't figure we'd think of this case... */
+ signum = sigfirst;
+ sigfirst = siglast;
+ siglast = signum;
}
}
- else if (signum == 0)
- error ("First argument is not a signal number.");
-
- /* 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))
+ else
{
- signal_print[signum] = 0;
- signal_stop[signum] = 0;
+ oursig = target_signal_from_name (*argv);
+ if (oursig != TARGET_SIGNAL_UNKNOWN)
+ {
+ sigfirst = siglast = (int) oursig;
+ }
+ else
+ {
+ /* Not a number and not a recognized flag word => complain. */
+ error ("Unrecognized or ambiguous flag word: \"%s\".", *argv);
+ }
}
- 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
+
+ /* If any signal numbers or symbol names were found, set flags for
+ which signals to apply actions to. */
+
+ for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
{
- p[wordlen] = 0;
- error ("Unrecognized flag word: \"%s\".", p);
+ switch ((enum target_signal) signum)
+ {
+ case TARGET_SIGNAL_TRAP:
+ case TARGET_SIGNAL_INT:
+ if (!allsigs && !sigs[signum])
+ {
+ if (query ("%s is used by the debugger.\n\
+Are you sure you want to change it? ",
+ target_signal_to_name
+ ((enum target_signal) signum)))
+ {
+ sigs[signum] = 1;
+ }
+ else
+ {
+ printf_unfiltered ("Not confirmed, unchanged.\n");
+ gdb_flush (gdb_stdout);
+ }
+ }
+ break;
+ case TARGET_SIGNAL_0:
+ case TARGET_SIGNAL_DEFAULT:
+ case TARGET_SIGNAL_UNKNOWN:
+ /* Make sure that "all" doesn't print these. */
+ break;
+ default:
+ sigs[signum] = 1;
+ break;
+ }
}
- /* Find start of next word. */
- p += wordlen;
- while (*p == ' ' || *p == '\t') p++;
+ argv++;
}
+ target_notice_signals (inferior_pid);
+
if (from_tty)
{
/* Show the results. */
- printf ("Number\tStop\tPrint\tPass to program\tDescription\n");
- printf ("%d\t", signum);
- printf ("%s\t", signal_stop[signum] ? "Yes" : "No");
- printf ("%s\t", signal_print[signum] ? "Yes" : "No");
- printf ("%s\t\t", signal_program[signum] ? "Yes" : "No");
- printf ("%s\n", sys_siglist[signum]);
+ sig_print_header ();
+ for (signum = 0; signum < nsigs; signum++)
+ {
+ if (sigs[signum])
+ {
+ sig_print_info (signum);
+ }
+ }
+ }
+
+ do_cleanups (old_chain);
+}
+
+static void
+xdb_handle_command (char *args, int from_tty)
+{
+ char **argv;
+ struct cleanup *old_chain;
+
+ /* Break the command line up into args. */
+
+ argv = buildargv (args);
+ if (argv == NULL)
+ {
+ nomem (0);
+ }
+ old_chain = make_cleanup_freeargv (argv);
+ if (argv[1] != (char *) NULL)
+ {
+ char *argBuf;
+ int bufLen;
+
+ bufLen = strlen (argv[0]) + 20;
+ argBuf = (char *) xmalloc (bufLen);
+ if (argBuf)
+ {
+ int validFlag = 1;
+ enum target_signal oursig;
+
+ oursig = target_signal_from_name (argv[0]);
+ memset (argBuf, 0, bufLen);
+ if (strcmp (argv[1], "Q") == 0)
+ sprintf (argBuf, "%s %s", argv[0], "noprint");
+ else
+ {
+ if (strcmp (argv[1], "s") == 0)
+ {
+ if (!signal_stop[oursig])
+ sprintf (argBuf, "%s %s", argv[0], "stop");
+ else
+ sprintf (argBuf, "%s %s", argv[0], "nostop");
+ }
+ else if (strcmp (argv[1], "i") == 0)
+ {
+ if (!signal_program[oursig])
+ sprintf (argBuf, "%s %s", argv[0], "pass");
+ else
+ sprintf (argBuf, "%s %s", argv[0], "nopass");
+ }
+ else if (strcmp (argv[1], "r") == 0)
+ {
+ if (!signal_print[oursig])
+ sprintf (argBuf, "%s %s", argv[0], "print");
+ else
+ sprintf (argBuf, "%s %s", argv[0], "noprint");
+ }
+ else
+ validFlag = 0;
+ }
+ if (validFlag)
+ handle_command (argBuf, from_tty);
+ else
+ printf_filtered ("Invalid signal handling flag.\n");
+ if (argBuf)
+ free (argBuf);
+ }
}
+ do_cleanups (old_chain);
}
-/* Print current contents of the tables set by the handle command. */
+/* Print current contents of the tables set by the handle command.
+ It is possible we should just be printing signals actually used
+ by the current target (but for things to work right when switching
+ targets, all signals should be in the signal tables). */
static void
-signals_info (signum_exp)
- char *signum_exp;
+signals_info (char *signum_exp, int from_tty)
{
- register int i;
- printf_filtered ("Number\tStop\tPrint\tPass to program\tDescription\n");
+ enum target_signal oursig;
+ sig_print_header ();
if (signum_exp)
{
- i = parse_and_eval_address (signum_exp);
- if (i >= NSIG || i < 0)
- error ("Signal number out of bounds.");
- printf_filtered ("%d\t", i);
- printf_filtered ("%s\t", signal_stop[i] ? "Yes" : "No");
- printf_filtered ("%s\t", signal_print[i] ? "Yes" : "No");
- printf_filtered ("%s\t\t", signal_program[i] ? "Yes" : "No");
- printf_filtered ("%s\n", sys_siglist[i]);
+ /* First see if this is a symbol name. */
+ oursig = target_signal_from_name (signum_exp);
+ if (oursig == TARGET_SIGNAL_UNKNOWN)
+ {
+ /* No, try numeric. */
+ oursig =
+ target_signal_from_command (parse_and_eval_address (signum_exp));
+ }
+ sig_print_info (oursig);
return;
}
printf_filtered ("\n");
- for (i = 0; i < NSIG; i++)
+ /* These ugly casts brought to you by the native VAX compiler. */
+ for (oursig = TARGET_SIGNAL_FIRST;
+ (int) oursig < (int) TARGET_SIGNAL_LAST;
+ oursig = (enum target_signal) ((int) oursig + 1))
{
QUIT;
- printf_filtered ("%d\t", i);
- printf_filtered ("%s\t", signal_stop[i] ? "Yes" : "No");
- printf_filtered ("%s\t", signal_print[i] ? "Yes" : "No");
- printf_filtered ("%s\t\t", signal_program[i] ? "Yes" : "No");
- printf_filtered ("%s\n", sys_siglist[i]);
+ if (oursig != TARGET_SIGNAL_UNKNOWN
+ && oursig != TARGET_SIGNAL_DEFAULT
+ && oursig != TARGET_SIGNAL_0)
+ sig_print_info (oursig);
}
printf_filtered ("\nUse the \"handle\" command to change these tables.\n");
}
\f
+struct inferior_status
+{
+ enum target_signal stop_signal;
+ CORE_ADDR stop_pc;
+ bpstat stop_bpstat;
+ int stop_step;
+ int stop_stack_dummy;
+ int stopped_by_random_signal;
+ int trap_expected;
+ CORE_ADDR step_range_start;
+ CORE_ADDR step_range_end;
+ CORE_ADDR step_frame_address;
+ int step_over_calls;
+ CORE_ADDR step_resume_break_address;
+ int stop_after_trap;
+ int stop_soon_quietly;
+ CORE_ADDR selected_frame_address;
+ char *stop_registers;
+
+ /* These are here because if call_function_by_hand has written some
+ registers and then decides to call error(), we better not have changed
+ any registers. */
+ char *registers;
+
+ int selected_level;
+ int breakpoint_proceeded;
+ int restore_stack_info;
+ int proceed_to_finish;
+};
+
+static struct inferior_status *
+xmalloc_inferior_status (void)
+{
+ struct inferior_status *inf_status;
+ inf_status = xmalloc (sizeof (struct inferior_status));
+ inf_status->stop_registers = xmalloc (REGISTER_BYTES);
+ inf_status->registers = xmalloc (REGISTER_BYTES);
+ return inf_status;
+}
+
+static void
+free_inferior_status (struct inferior_status *inf_status)
+{
+ free (inf_status->registers);
+ free (inf_status->stop_registers);
+ free (inf_status);
+}
+
+void
+write_inferior_status_register (struct inferior_status *inf_status, int regno,
+ LONGEST val)
+{
+ int size = REGISTER_RAW_SIZE (regno);
+ void *buf = alloca (size);
+ store_signed_integer (buf, size, val);
+ memcpy (&inf_status->registers[REGISTER_BYTE (regno)], buf, size);
+}
+
/* Save all of the information associated with the inferior<==>gdb
connection. INF_STATUS is a pointer to a "struct inferior_status"
(defined in inferior.h). */
-struct command_line *get_breakpoint_commands ();
-
-void
-save_inferior_status (inf_status, restore_stack_info)
- struct inferior_status *inf_status;
- int restore_stack_info;
+struct inferior_status *
+save_inferior_status (int restore_stack_info)
{
- inf_status->pc_changed = pc_changed;
+ struct inferior_status *inf_status = xmalloc_inferior_status ();
+
inf_status->stop_signal = stop_signal;
inf_status->stop_pc = stop_pc;
- inf_status->stop_frame_address = stop_frame_address;
- inf_status->stop_breakpoint = stop_breakpoint;
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->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_after_attach = stop_after_attach;
- inf_status->breakpoint_commands = get_breakpoint_commands ();
+ 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_inferior_status is
+ called. */
+ inf_status->stop_bpstat = stop_bpstat;
+ stop_bpstat = bpstat_copy (stop_bpstat);
+ inf_status->breakpoint_proceeded = breakpoint_proceeded;
inf_status->restore_stack_info = restore_stack_info;
-
- bcopy (stop_registers, inf_status->stop_registers, REGISTER_BYTES);
-
+ inf_status->proceed_to_finish = proceed_to_finish;
+
+ memcpy (inf_status->stop_registers, stop_registers, REGISTER_BYTES);
+
+ read_register_bytes (0, inf_status->registers, REGISTER_BYTES);
+
record_selected_frame (&(inf_status->selected_frame_address),
&(inf_status->selected_level));
- return;
+ return inf_status;
}
-void
-restore_inferior_status (inf_status)
- struct inferior_status *inf_status;
+struct restore_selected_frame_args
+{
+ CORE_ADDR frame_address;
+ int level;
+};
+
+static int
+restore_selected_frame (void *args)
{
- FRAME fid;
- int level = inf_status->selected_level;
+ struct restore_selected_frame_args *fr =
+ (struct restore_selected_frame_args *) args;
+ struct frame_info *frame;
+ int level = fr->level;
+
+ frame = find_relative_frame (get_current_frame (), &level);
+
+ /* If inf_status->selected_frame_address is NULL, there was no
+ previously selected frame. */
+ if (frame == NULL ||
+ /* FRAME_FP (frame) != fr->frame_address || */
+ /* elz: deleted this check as a quick fix to the problem that
+ for function called by hand gdb creates no internal frame
+ structure and the real stack and gdb's idea of stack are
+ different if nested calls by hands are made.
+
+ mvs: this worries me. */
+ level != 0)
+ {
+ warning ("Unable to restore previously selected frame.\n");
+ return 0;
+ }
+
+ select_frame (frame, fr->level);
+
+ return (1);
+}
- pc_changed = inf_status->pc_changed;
+void
+restore_inferior_status (struct inferior_status *inf_status)
+{
stop_signal = inf_status->stop_signal;
stop_pc = inf_status->stop_pc;
- stop_frame_address = inf_status->stop_frame_address;
- stop_breakpoint = inf_status->stop_breakpoint;
stop_step = inf_status->stop_step;
stop_stack_dummy = inf_status->stop_stack_dummy;
stopped_by_random_signal = inf_status->stopped_by_random_signal;
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_after_attach = inf_status->stop_after_attach;
- set_breakpoint_commands (inf_status->breakpoint_commands);
+ 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);
+ /* FIXME: Is the restore of stop_registers always needed */
+ memcpy (stop_registers, inf_status->stop_registers, REGISTER_BYTES);
/* The inferior can be gone if the user types "print exit(0)"
(and perhaps other times). */
- if (have_inferior_p() && inf_status->restore_stack_info)
+ if (target_has_execution)
+ write_register_bytes (0, inf_status->registers, REGISTER_BYTES);
+
+ /* FIXME: If we are being called after stopping in a function which
+ is called from gdb, we should not be trying to restore the
+ selected frame; it just prints a spurious error message (The
+ message is useful, however, in detecting bugs in gdb (like if gdb
+ clobbers the stack)). In fact, should we be restoring the
+ inferior status at all in that case? . */
+
+ if (target_has_stack && inf_status->restore_stack_info)
{
- fid = find_relative_frame (get_current_frame (),
- &level);
+ struct restore_selected_frame_args fr;
+ fr.level = inf_status->selected_level;
+ fr.frame_address = inf_status->selected_frame_address;
+ /* The point of catch_errors is that if the stack is clobbered,
+ walking the stack might encounter a garbage pointer and error()
+ trying to dereference it. */
+ if (catch_errors (restore_selected_frame, &fr,
+ "Unable to restore previously selected frame:\n",
+ RETURN_MASK_ERROR) == 0)
+ /* Error in restoring the selected frame. Select the innermost
+ frame. */
+
+
+ select_frame (get_current_frame (), 0);
- if (fid == 0 ||
- FRAME_FP (fid) != inf_status->selected_frame_address ||
- level != 0)
- {
- /* 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");
- select_frame (get_current_frame (), 0);
- return;
- }
-
- select_frame (fid, inf_status->selected_level);
}
- return;
+
+ free_inferior_status (inf_status);
+}
+
+void
+discard_inferior_status (struct inferior_status *inf_status)
+{
+ /* See save_inferior_status for info on stop_bpstat. */
+ bpstat_clear (&inf_status->stop_bpstat);
+ free_inferior_status (inf_status);
}
+static void
+set_follow_fork_mode_command (char *arg, int from_tty,
+ struct cmd_list_element *c)
+{
+ if (!STREQ (arg, "parent") &&
+ !STREQ (arg, "child") &&
+ !STREQ (arg, "both") &&
+ !STREQ (arg, "ask"))
+ error ("follow-fork-mode must be one of \"parent\", \"child\", \"both\" or \"ask\".");
+
+ if (follow_fork_mode_string != NULL)
+ free (follow_fork_mode_string);
+ follow_fork_mode_string = savestring (arg, strlen (arg));
+}
\f
+static void
+build_infrun (void)
+{
+ stop_registers = xmalloc (REGISTER_BYTES);
+}
+
void
-_initialize_infrun ()
+_initialize_infrun (void)
{
register int i;
+ register int numsigs;
+ struct cmd_list_element *c;
+
+ build_infrun ();
+
+ register_gdbarch_swap (&stop_registers, sizeof (stop_registers), NULL);
+ register_gdbarch_swap (NULL, 0, build_infrun);
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.");
+Specify a signal as argument to print info on that signal only.");
+ add_info_alias ("handle", "signals", 0);
add_com ("handle", class_run, handle_command,
- "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\
+ concat ("Specify how to handle a signal.\n\
+Args are signals and actions to apply to those signals.\n\
+Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
+from 1-15 are allowed for compatibility with old versions of GDB.\n\
+Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
+The special arg \"all\" is recognized to mean all signals except those\n\
+used by the debugger, typically SIGTRAP and SIGINT.\n",
+ "Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
+\"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
+Stop means reenter debugger if this signal happens (implies print).\n\
Print means print a message if this signal happens.\n\
+Pass means let program see this signal; otherwise program doesn't know.\n\
+Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
+Pass and Stop may be combined.", NULL));
+ if (xdb_commands)
+ {
+ add_com ("lz", class_info, signals_info,
+ "What debugger does when program gets various signals.\n\
+Specify a signal as argument to print info on that signal only.");
+ add_com ("z", class_run, xdb_handle_command,
+ concat ("Specify how to handle a signal.\n\
+Args are signals and actions to apply to those signals.\n\
+Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
+from 1-15 are allowed for compatibility with old versions of GDB.\n\
+Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
+The special arg \"all\" is recognized to mean all signals except those\n\
+used by the debugger, typically SIGTRAP and SIGINT.\n",
+ "Recognized actions include \"s\" (toggles between stop and nostop), \n\
+\"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
+nopass), \"Q\" (noprint)\n\
Stop means reenter debugger if this signal happens (implies print).\n\
+Print means print a message if this signal happens.\n\
Pass means let program see this signal; otherwise program doesn't know.\n\
-Pass and Stop may be combined.");
+Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
+Pass and Stop may be combined.", NULL));
+ }
- for (i = 0; i < NSIG; i++)
+ if (!dbx_commands)
+ stop_command = add_cmd ("stop", class_obscure, not_just_help_class_command,
+ "There is no `stop' command, but you can set a hook on `stop'.\n\
+This allows you to set a list of commands to be run each time execution\n\
+of the program stops.", &cmdlist);
+
+ numsigs = (int) TARGET_SIGNAL_LAST;
+ signal_stop = (unsigned char *)
+ xmalloc (sizeof (signal_stop[0]) * numsigs);
+ signal_print = (unsigned char *)
+ xmalloc (sizeof (signal_print[0]) * numsigs);
+ signal_program = (unsigned char *)
+ xmalloc (sizeof (signal_program[0]) * numsigs);
+ for (i = 0; i < numsigs; i++)
{
signal_stop[i] = 1;
signal_print[i] = 1;
/* Signals caused by debugger's own actions
should not be given to the program afterwards. */
- signal_program[SIGTRAP] = 0;
- signal_program[SIGINT] = 0;
+ signal_program[TARGET_SIGNAL_TRAP] = 0;
+ signal_program[TARGET_SIGNAL_INT] = 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 */
-}
+ signal_stop[TARGET_SIGNAL_ALRM] = 0;
+ signal_print[TARGET_SIGNAL_ALRM] = 0;
+ signal_stop[TARGET_SIGNAL_VTALRM] = 0;
+ signal_print[TARGET_SIGNAL_VTALRM] = 0;
+ signal_stop[TARGET_SIGNAL_PROF] = 0;
+ signal_print[TARGET_SIGNAL_PROF] = 0;
+ signal_stop[TARGET_SIGNAL_CHLD] = 0;
+ signal_print[TARGET_SIGNAL_CHLD] = 0;
+ signal_stop[TARGET_SIGNAL_IO] = 0;
+ signal_print[TARGET_SIGNAL_IO] = 0;
+ signal_stop[TARGET_SIGNAL_POLL] = 0;
+ signal_print[TARGET_SIGNAL_POLL] = 0;
+ signal_stop[TARGET_SIGNAL_URG] = 0;
+ signal_print[TARGET_SIGNAL_URG] = 0;
+ signal_stop[TARGET_SIGNAL_WINCH] = 0;
+ signal_print[TARGET_SIGNAL_WINCH] = 0;
+
+ /* These signals are used internally by user-level thread
+ implementations. (See signal(5) on Solaris.) Like the above
+ signals, a healthy program receives and handles them as part of
+ its normal operation. */
+ signal_stop[TARGET_SIGNAL_LWP] = 0;
+ signal_print[TARGET_SIGNAL_LWP] = 0;
+ signal_stop[TARGET_SIGNAL_WAITING] = 0;
+ signal_print[TARGET_SIGNAL_WAITING] = 0;
+ signal_stop[TARGET_SIGNAL_CANCEL] = 0;
+ signal_print[TARGET_SIGNAL_CANCEL] = 0;
+
+#ifdef SOLIB_ADD
+ add_show_from_set
+ (add_set_cmd ("stop-on-solib-events", class_support, var_zinteger,
+ (char *) &stop_on_solib_events,
+ "Set stopping for shared library events.\n\
+If nonzero, gdb will give control to the user when the dynamic linker\n\
+notifies gdb of shared library events. The most common event of interest\n\
+to the user would be loading/unloading of a new library.\n",
+ &setlist),
+ &showlist);
+#endif
+ c = add_set_enum_cmd ("follow-fork-mode",
+ class_run,
+ follow_fork_mode_kind_names,
+ (char *) &follow_fork_mode_string,
+/* ??rehrauer: The "both" option is broken, by what may be a 10.20
+ kernel problem. It's also not terribly useful without a GUI to
+ help the user drive two debuggers. So for now, I'm disabling
+ the "both" option. */
+/* "Set debugger response to a program call of fork \
+ or vfork.\n\
+ A fork or vfork creates a new process. follow-fork-mode can be:\n\
+ parent - the original process is debugged after a fork\n\
+ child - the new process is debugged after a fork\n\
+ both - both the parent and child are debugged after a fork\n\
+ ask - the debugger will ask for one of the above choices\n\
+ For \"both\", another copy of the debugger will be started to follow\n\
+ the new child process. The original debugger will continue to follow\n\
+ the original parent process. To distinguish their prompts, the\n\
+ debugger copy's prompt will be changed.\n\
+ For \"parent\" or \"child\", the unfollowed process will run free.\n\
+ By default, the debugger will follow the parent process.",
+ */
+ "Set debugger response to a program call of fork \
+or vfork.\n\
+A fork or vfork creates a new process. follow-fork-mode can be:\n\
+ parent - the original process is debugged after a fork\n\
+ child - the new process is debugged after a fork\n\
+ ask - the debugger will ask for one of the above choices\n\
+For \"parent\" or \"child\", the unfollowed process will run free.\n\
+By default, the debugger will follow the parent process.",
+ &setlist);
+/* c->function.sfunc = ; */
+ add_show_from_set (c, &showlist);
+
+ set_follow_fork_mode_command ("parent", 0, NULL);
+
+ c = add_set_enum_cmd ("scheduler-locking", class_run,
+ scheduler_enums, /* array of string names */
+ (char *) &scheduler_mode, /* current mode */
+ "Set mode for locking scheduler during execution.\n\
+off == no locking (threads may preempt at any time)\n\
+on == full locking (no thread except the current thread may run)\n\
+step == scheduler locked during every single-step operation.\n\
+ In this mode, no other thread may run during a step command.\n\
+ Other threads may run while stepping over a function call ('next').",
+ &setlist);
+
+ c->function.sfunc = set_schedlock_func; /* traps on target vector */
+ add_show_from_set (c, &showlist);
+}
projects / deliverable / binutils-gdb.git / blobdiff