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Diffstat (limited to 'gdb/infrun.c')
| -rw-r--r-- | gdb/infrun.c | 3775 |
1 files changed, 3775 insertions, 0 deletions
diff --git a/gdb/infrun.c b/gdb/infrun.c new file mode 100644 index 00000000000..5fd8fc107c7 --- /dev/null +++ b/gdb/infrun.c @@ -0,0 +1,3775 @@ +/* Target-struct-independent code to start (run) and stop an inferior process. + Copyright 1986, 87, 88, 89, 91, 92, 93, 94, 95, 96, 97, 1998 + Free Software Foundation, Inc. + +This file is part of GDB. + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with this program; if not, write to the Free Software +Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +#include "defs.h" +#include "gdb_string.h" +#include <ctype.h> +#include "symtab.h" +#include "frame.h" +#include "inferior.h" +#include "breakpoint.h" +#include "wait.h" +#include "gdbcore.h" +#include "gdbcmd.h" +#include "target.h" +#include "gdbthread.h" +#include "annotate.h" +#include "symfile.h" /* for overlay functions */ + +#include <signal.h> + +/* Prototypes for local functions */ + +static void signals_info PARAMS ((char *, int)); + +static void handle_command PARAMS ((char *, int)); + +static void sig_print_info PARAMS ((enum target_signal)); + +static void sig_print_header PARAMS ((void)); + +static void resume_cleanups PARAMS ((int)); + +static int hook_stop_stub PARAMS ((PTR)); + +static void delete_breakpoint_current_contents PARAMS ((PTR)); + +int inferior_ignoring_startup_exec_events = 0; +int inferior_ignoring_leading_exec_events = 0; + +#ifdef HPUXHPPA +/* 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 switched_from_inferior_pid; +#endif + +/* 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; + +void _initialize_infrun PARAMS ((void)); + +/* 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. */ + +#ifndef GET_LONGJMP_TARGET +#define GET_LONGJMP_TARGET(PC_ADDR) 0 +#endif + + +/* 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 + +/* 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 + +/* On SVR4 based systems, determining the callee's address is exceedingly + difficult and depends on the implementation of the run time loader. + If we are stepping at the source level, we single step until we exit + the run time loader code and reach the callee's address. */ + +#ifndef IN_SOLIB_DYNSYM_RESOLVE_CODE +#define IN_SOLIB_DYNSYM_RESOLVE_CODE(pc) 0 +#endif + +/* For SVR4 shared libraries, each call goes through a small piece of + trampoline code in the ".plt" section. IN_SOLIB_CALL_TRAMPOLINE evaluates + to nonzero if we are current stopped in one of these. */ + +#ifndef IN_SOLIB_CALL_TRAMPOLINE +#define IN_SOLIB_CALL_TRAMPOLINE(pc,name) 0 +#endif + +/* In some shared library schemes, the return path from a shared library + call may need to go through a trampoline too. */ + +#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 + +/* 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; + +#define SET_SIGS(nsigs,sigs,flags) \ + do { \ + int signum = (nsigs); \ + while (signum-- > 0) \ + if ((sigs)[signum]) \ + (flags)[signum] = 1; \ + } while (0) + +#define UNSET_SIGS(nsigs,sigs,flags) \ + do { \ + int signum = (nsigs); \ + while (signum-- > 0) \ + if ((sigs)[signum]) \ + (flags)[signum] = 0; \ + } while (0) + + +/* Command list pointer for the "stop" placeholder. */ + +static struct cmd_list_element *stop_command; + +/* Nonzero if breakpoints are now inserted in the inferior. */ + +static int breakpoints_inserted; + +/* Function inferior was in as of last step command. */ + +static struct symbol *step_start_function; + +/* 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 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 stop_soon_quietly; + +/* Nonzero if proceed is being used for a "finish" command or a similar + situation when stop_registers should be saved. */ + +int proceed_to_finish; + +/* 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]; + +/* Nonzero if program stopped due to error trying to insert breakpoints. */ + +static int breakpoints_failed; + +/* Nonzero after stop if current stack frame should be printed. */ + +static int stop_print_frame; + +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; + + +#if defined(HPUXHPPA) +static void +follow_inferior_fork (parent_pid, child_pid, has_forked, has_vforked) + int parent_pid; + int child_pid; + int has_forked; + int has_vforked; +{ + int followed_parent = 0; + int followed_child = 0; + int ima_clone = 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); + SOLIB_REMOVE_INFERIOR_HOOK (child_pid); + } + + /* 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. */ + SOLIB_REMOVE_INFERIOR_HOOK (inferior_pid); + + /* 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; + + free (follow_mode); +} + +static void +follow_fork (parent_pid, child_pid) + int parent_pid; + int child_pid; +{ + follow_inferior_fork (parent_pid, child_pid, 1, 0); +} + + +/* Forward declaration. */ +static void follow_exec PARAMS ((int, char *)); + +static void +follow_vfork (parent_pid, child_pid) + 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); + } +} +#endif /* HPUXHPPA */ + +static void +follow_exec (pid, execd_pathname) + int pid; + char *execd_pathname; +{ +#ifdef HPUXHPPA + int saved_pid = pid; + extern struct target_ops child_ops; + + /* 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. */ + gdb_flush (gdb_stdout); + target_mourn_inferior (); + inferior_pid = saved_pid; /* Because mourn_inferior resets inferior_pid. */ + push_target (&child_ops); + + /* 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. */ + SOLIB_RESTART (); + SOLIB_CREATE_INFERIOR_HOOK (inferior_pid); + + /* 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.) */ +#endif +} + +/* 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; + + +/* Things to clean up if we QUIT out of resume (). */ +/* ARGSUSED */ +static void +resume_cleanups (arg) + 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 (args, from_tty, c) + 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 (step, sig) + 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 + + 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 + +#ifdef HPUXHPPA + /* 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; + } +#endif /* HPUXHPPA */ + + /* Install inferior's terminal modes. */ + target_terminal_inferior (); + + if (should_resume) + { +#ifdef HPUXHPPA + if (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. */ + target_resume (-1, step, sig); + } + else + { + if (!step) + { + warning ("Internal error, changing continue to step."); + remove_breakpoints (); + breakpoints_inserted = 0; + trap_expected = 1; + step = 1; + } + + target_resume (inferior_pid, step, sig); + } + } + else +#endif /* HPUXHPPA */ + { + /* Vanilla resume. */ + + if ((scheduler_mode == schedlock_on) || + (scheduler_mode == schedlock_step && step != 0)) + target_resume (inferior_pid, step, sig); + else + target_resume (-1, step, sig); + } + } + + discard_cleanups (old_cleanups); +} + + +/* Clear out all variables saying what to do when inferior is continued. + First do this, then set the ones you want, then call `proceed'. */ + +void +clear_proceed_status () +{ + trap_expected = 0; + step_range_start = 0; + step_range_end = 0; + step_frame_address = 0; + step_over_calls = -1; + stop_after_trap = 0; + stop_soon_quietly = 0; + proceed_to_finish = 0; + breakpoint_proceeded = 1; /* We're about to proceed... */ + + /* Discard any remaining commands or status from previous stop. */ + bpstat_clear (&stop_bpstat); +} + +/* Basic routine for continuing the program in various fashions. + + ADDR is the address to resume at, or -1 for resume where stopped. + SIGGNAL is the signal to give it, or 0 for none, + or -1 for act according to how it stopped. + STEP is nonzero if should trap after one instruction. + -1 means return after that and print nothing. + You should probably set various step_... variables + before calling here, if you are stepping. + + You should call clear_proceed_status before calling proceed. */ + +void +proceed (addr, siggnal, step) + CORE_ADDR addr; + enum target_signal siggnal; + int step; +{ + int oneproc = 0; + + if (step > 0) + step_start_function = find_pc_function (read_pc ()); + if (step < 0) + stop_after_trap = 1; + + if (addr == (CORE_ADDR) - 1) + { + /* If there is a breakpoint at the address we will resume at, + step one instruction before inserting breakpoints + so that we do not stop right away (and report a second + hit at this breakpoint). */ + + if (read_pc () == stop_pc && breakpoint_here_p (read_pc ())) + oneproc = 1; + +#ifndef STEP_SKIPS_DELAY +#define STEP_SKIPS_DELAY(pc) (0) +#define STEP_SKIPS_DELAY_P (0) +#endif + /* Check breakpoint_here_p first, because breakpoint_here_p is fast + (it just checks internal GDB data structures) and STEP_SKIPS_DELAY + is slow (it needs to read memory from the target). */ + if (STEP_SKIPS_DELAY_P + && breakpoint_here_p (read_pc () + 4) + && STEP_SKIPS_DELAY (read_pc ())) + oneproc = 1; + } + else + { + write_pc (addr); + + /* 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 () && 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. */ + oneproc = 1; + trap_expected_after_continue = 0; + } +#endif /* HP_OS_BUG */ + + if (oneproc) + /* We will get a trace trap after one instruction. + Continue it automatically and insert breakpoints then. */ + trap_expected = 1; + else + { + int temp = insert_breakpoints (); + if (temp) + { + print_sys_errmsg ("ptrace", temp); + error ("Cannot insert breakpoints.\n\ +The same program may be running in another process."); + } + + breakpoints_inserted = 1; + } + + if (siggnal != TARGET_SIGNAL_DEFAULT) + stop_signal = siggnal; + /* If this signal should not be seen by program, + give it zero. Used for debugging signals. */ + else if (!signal_program[stop_signal]) + stop_signal = TARGET_SIGNAL_0; + + annotate_starting (); + + /* Make sure that output from GDB appears before output from the + inferior. */ + gdb_flush (gdb_stdout); + + /* Resume inferior. */ + resume (oneproc || step || bpstat_should_step (), stop_signal); + + /* Wait for it to stop (if not standalone) + and in any case decode why it stopped, and act accordingly. */ + + wait_for_inferior (); + normal_stop (); +} + +/* 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; + + +/* Start remote-debugging of a machine over a serial link. */ + +void +start_remote () +{ + init_thread_list (); + init_wait_for_inferior (); + stop_soon_quietly = 1; + trap_expected = 0; + wait_for_inferior (); + normal_stop (); +} + +/* Initialize static vars when a new inferior begins. */ + +void +init_wait_for_inferior () +{ + /* These are meaningless until the first time through wait_for_inferior. */ + prev_pc = 0; + prev_func_start = 0; + prev_func_name = NULL; + +#ifdef HP_OS_BUG + trap_expected_after_continue = 0; +#endif + breakpoints_inserted = 0; + breakpoint_init_inferior (inf_starting); + + /* Don't confuse first call to proceed(). */ + stop_signal = TARGET_SIGNAL_0; + + /* The first resume is not following a fork/vfork/exec. */ + pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */ + 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; + + clear_proceed_status (); +} + +static void +delete_breakpoint_current_contents (arg) + PTR arg; +{ + struct breakpoint **breakpointp = (struct breakpoint **) arg; + if (*breakpointp != NULL) + { + delete_breakpoint (*breakpointp); + *breakpointp = NULL; + } +} + +/* 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 () +{ + struct cleanup *old_cleanups; + struct target_waitstatus w; + int another_trap; + int random_signal = 0; + CORE_ADDR stop_func_start; + CORE_ADDR stop_func_end; + char *stop_func_name; +#if 0 + CORE_ADDR prologue_pc = 0; +#endif + CORE_ADDR tmp; + struct symtab_and_line sal; + int remove_breakpoints_on_following_step = 0; + int current_line; + struct symtab *current_symtab; + int handling_longjmp = 0; /* FIXME */ + int pid; + int saved_inferior_pid; + int update_step_sp = 0; + int stepping_through_solib_after_catch = 0; + bpstat stepping_through_solib_catchpoints = NULL; + int enable_hw_watchpoints_after_wait = 0; + int stepping_through_sigtramp = 0; + int new_thread_event; + +#ifdef HAVE_NONSTEPPABLE_WATCHPOINT + int stepped_after_stopped_by_watchpoint; +#endif + + old_cleanups = make_cleanup (delete_breakpoint_current_contents, + &step_resume_breakpoint); + make_cleanup (delete_breakpoint_current_contents, + &through_sigtramp_breakpoint); + sal = find_pc_line (prev_pc, 0); + current_line = sal.line; + current_symtab = sal.symtab; + + /* Are we stepping? */ +#define CURRENTLY_STEPPING() \ + ((through_sigtramp_breakpoint == NULL \ + && !handling_longjmp \ + && ((step_range_end && step_resume_breakpoint == NULL) \ + || trap_expected)) \ + || stepping_through_solib_after_catch \ + || bpstat_should_step ()) + ; + thread_step_needed = 0; + +#ifdef HPUXHPPA + /* We'll update this if & when we switch to a new thread. */ + switched_from_inferior_pid = inferior_pid; +#endif + + while (1) + { + extern int overlay_cache_invalid; /* declared in symfile.h */ + + overlay_cache_invalid = 1; + + /* We have to invalidate the registers BEFORE calling target_wait because + they can be loaded from the target while in target_wait. This makes + remote debugging a bit more efficient for those targets that provide + critical registers as part of their normal status mechanism. */ + + registers_changed (); + + if (target_wait_hook) + pid = target_wait_hook (-1, &w); + else + pid = target_wait (-1, &w); + + /* 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 (enable_hw_watchpoints_after_wait) + { + TARGET_ENABLE_HW_WATCHPOINTS (inferior_pid); + enable_hw_watchpoints_after_wait = 0; + } + + +#ifdef HAVE_NONSTEPPABLE_WATCHPOINT + stepped_after_stopped_by_watchpoint = 0; +#endif + + /* Gross. + + We goto this label from elsewhere in wait_for_inferior when we want + to continue the main loop without calling "wait" and trashing the + waitstatus contained in W. */ + have_waited: + + flush_cached_frames (); + + /* If it's a new process, add it to the thread database */ + + new_thread_event = ((pid != inferior_pid) && !in_thread_list (pid)); + + if (w.kind != TARGET_WAITKIND_EXITED + && w.kind != TARGET_WAITKIND_SIGNALLED + && new_thread_event) + { + add_thread (pid); + + +#ifdef HPUXHPPA + fprintf_unfiltered (gdb_stderr, "[New %s]\n", + target_pid_or_tid_to_str (pid)); + +#else + printf_filtered ("[New %s]\n", target_pid_to_str (pid)); +#endif + +#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); + continue; +#endif + } + + switch (w.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) + { + extern int auto_solib_add; + + /* Remove breakpoints, SOLIB_ADD might adjust + breakpoint addresses via breakpoint_re_set. */ + if (breakpoints_inserted) + remove_breakpoints (); + + /* Check for any newly added shared libraries if we're + supposed to be adding them automatically. */ + if (auto_solib_add) + { + /* Switch terminal for any messages produced by + breakpoint_re_set. */ + target_terminal_ours_for_output (); + SOLIB_ADD (NULL, 0, NULL); + target_terminal_inferior (); + } + + /* Reinsert breakpoints and continue. */ + if (breakpoints_inserted) + insert_breakpoints (); + } +#endif + resume (0, TARGET_SIGNAL_0); + continue; + + case TARGET_WAITKIND_SPURIOUS: + resume (0, TARGET_SIGNAL_0); + continue; + + case TARGET_WAITKIND_EXITED: + target_terminal_ours (); /* Must do this before mourn anyway */ + annotate_exited (w.value.integer); + if (w.value.integer) + printf_filtered ("\nProgram exited with code 0%o.\n", + (unsigned int) w.value.integer); + else + printf_filtered ("\nProgram exited normally.\n"); + + /* 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) w.value.integer)); + gdb_flush (gdb_stdout); + target_mourn_inferior (); + singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P*/ + stop_print_frame = 0; + goto stop_stepping; + + case TARGET_WAITKIND_SIGNALLED: + stop_print_frame = 0; + stop_signal = w.value.sig; + target_terminal_ours (); /* Must do this before mourn anyway */ + annotate_signalled (); + + /* 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 */ + + printf_filtered ("\nProgram terminated with signal "); + annotate_signal_name (); + printf_filtered ("%s", target_signal_to_name (stop_signal)); + annotate_signal_name_end (); + printf_filtered (", "); + annotate_signal_string (); + printf_filtered ("%s", target_signal_to_string (stop_signal)); + annotate_signal_string_end (); + printf_filtered (".\n"); + + printf_filtered ("The program no longer exists.\n"); + gdb_flush (gdb_stdout); + singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P*/ + goto stop_stepping; + + /* 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 = w.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 == pid) + { + pending_follow.fork_event.saw_parent_fork = 1; + pending_follow.fork_event.parent_pid = pid; + pending_follow.fork_event.child_pid = w.value.related_pid; + continue; + } + else + { + pending_follow.fork_event.saw_child_fork = 1; + pending_follow.fork_event.child_pid = pid; + pending_follow.fork_event.parent_pid = w.value.related_pid; + } + + stop_pc = read_pc_pid (pid); + saved_inferior_pid = inferior_pid; + inferior_pid = pid; + stop_bpstat = bpstat_stop_status + (&stop_pc, +#if DECR_PC_AFTER_BREAK + (prev_pc != stop_pc - DECR_PC_AFTER_BREAK + && CURRENTLY_STEPPING ()) +#else /* DECR_PC_AFTER_BREAK zero */ + 0 +#endif /* DECR_PC_AFTER_BREAK zero */ + ); + random_signal = !bpstat_explains_signal (stop_bpstat); + inferior_pid = 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 = w.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 (pid == inferior_pid) + { + pending_follow.fork_event.saw_parent_fork = 1; + pending_follow.fork_event.parent_pid = pid; + pending_follow.fork_event.child_pid = w.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 = pid; + pending_follow.fork_event.parent_pid = w.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 (pid, 0, TARGET_SIGNAL_0); + continue; + } + } + + stop_pc = read_pc (); + stop_bpstat = bpstat_stop_status + (&stop_pc, +#if DECR_PC_AFTER_BREAK + (prev_pc != stop_pc - DECR_PC_AFTER_BREAK + && CURRENTLY_STEPPING ()) +#else /* DECR_PC_AFTER_BREAK zero */ + 0 +#endif /* DECR_PC_AFTER_BREAK zero */ + ); + 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 (pid, 0, TARGET_SIGNAL_0); + continue; + } + inferior_ignoring_leading_exec_events = + target_reported_exec_events_per_exec_call () - 1; + + pending_follow.execd_pathname = savestring (w.value.execd_pathname, + strlen (w.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 (pid, 1, TARGET_SIGNAL_0); + /* We expect the parent vfork event to be available now. */ + continue; + } + + /* 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 (pid); + saved_inferior_pid = inferior_pid; + inferior_pid = pid; + stop_bpstat = bpstat_stop_status + (&stop_pc, +#if DECR_PC_AFTER_BREAK + (prev_pc != stop_pc - DECR_PC_AFTER_BREAK + && CURRENTLY_STEPPING ()) +#else /* DECR_PC_AFTER_BREAK zero */ + 0 +#endif /* DECR_PC_AFTER_BREAK zero */ + ); + random_signal = !bpstat_explains_signal (stop_bpstat); + inferior_pid = 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); + continue; + + /* 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 enable_hw_watchpoints_after_wait + here, which will be serviced immediately after the target + is waited on. */ + case TARGET_WAITKIND_SYSCALL_RETURN: + target_resume (pid, 1, TARGET_SIGNAL_0); + + if (number_of_threads_in_syscalls > 0) + { + number_of_threads_in_syscalls--; + enable_hw_watchpoints_after_wait = + (number_of_threads_in_syscalls == 0); + } + continue; + + case TARGET_WAITKIND_STOPPED: + stop_signal = w.value.sig; + break; + } + + /* 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 (new_thread_event) + { + target_resume (-1, 0, TARGET_SIGNAL_0); + continue; + } + + stop_pc = read_pc_pid (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) + random_signal = 0; + else if (breakpoints_inserted + && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK)) + { + random_signal = 0; + if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK, + pid)) + { + 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, 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, pid); + } + else + { /* Single step */ + target_resume (pid, 1, TARGET_SIGNAL_0); + /* FIXME: What if a signal arrives instead of the + single-step happening? */ + + if (target_wait_hook) + target_wait_hook (pid, &w); + else + target_wait (pid, &w); + insert_breakpoints (); + } + + /* We need to restart all the threads now. */ + target_resume (-1, 0, TARGET_SIGNAL_0); + continue; + } + 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 + 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 ((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 (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 (pid, 0, stop_signal); + continue; + } + + /* It's a SIGTRAP or a signal we're interested in. Switch threads, + and fall into the rest of wait_for_inferior(). */ + + /* 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, handling_longjmp, + another_trap, + stepping_through_solib_after_catch, + stepping_through_solib_catchpoints, + stepping_through_sigtramp); + +#ifdef HPUXHPPA + switched_from_inferior_pid = inferior_pid; +#endif + + inferior_pid = pid; + + /* Load infrun state for the new thread. */ + load_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, &handling_longjmp, + &another_trap, + &stepping_through_solib_after_catch, + &stepping_through_solib_catchpoints, + &stepping_through_sigtramp); + + if (context_hook) + context_hook (pid_to_thread_id (pid)); + + printf_filtered ("[Switching to %s]\n", target_pid_to_str (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 0 /* XXX DEBUG */ + printf ("infrun.c:1607: pc = 0x%x\n", read_pc ()); +#endif + /* if (INSTRUCTION_NULLIFIED && CURRENTLY_STEPPING ()) */ + if (INSTRUCTION_NULLIFIED) + { + struct target_waitstatus tmpstatus; +#if 0 + all_registers_info ((char *) 0, 0); +#endif + registers_changed (); + target_resume (pid, 1, TARGET_SIGNAL_0); + + /* We may have received a signal that we want to pass to + the inferior; therefore, we must not clobber the waitstatus + in W. So we call wait ourselves, then continue the loop + at the "have_waited" label. */ + if (target_wait_hook) + target_wait_hook (pid, &tmpstatus); + else + target_wait (pid, &tmpstatus); + + goto have_waited; + } + +#ifdef HAVE_STEPPABLE_WATCHPOINT + /* 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 (STOPPED_BY_WATCHPOINT (w)) + { + resume (1, 0); + continue; + } +#endif + +#ifdef HAVE_NONSTEPPABLE_WATCHPOINT + /* 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 (STOPPED_BY_WATCHPOINT (w)) + { +/* 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 (pid, 1, TARGET_SIGNAL_0); /* Single step */ + + if (target_wait_hook) + target_wait_hook (pid, &w); + else + target_wait (pid, &w); + 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; + goto have_waited; + } +#endif + +#ifdef HAVE_CONTINUABLE_WATCHPOINT + /* It may be possible to simply continue after a watchpoint. */ + STOPPED_BY_WATCHPOINT (w); +#endif + + stop_func_start = 0; + stop_func_end = 0; + stop_func_name = 0; + /* Don't care about return value; stop_func_start and stop_func_name + will both be 0 if it doesn't work. */ + find_pc_partial_function (stop_pc, &stop_func_name, &stop_func_start, + &stop_func_end); + stop_func_start += FUNCTION_START_OFFSET; + another_trap = 0; + bpstat_clear (&stop_bpstat); + stop_step = 0; + stop_stack_dummy = 0; + stop_print_frame = 1; + 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. */ + + /* 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; + break; + } + if (stop_soon_quietly) + break; + + /* Don't even think about breakpoints + if just proceeded over a breakpoint. + + However, if we are trying to proceed over a breakpoint + and end up in sigtramp, then 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, + (DECR_PC_AFTER_BREAK ? + /* Notice the case of stepping through a jump + that lands just after a breakpoint. + Don't confuse that with hitting the breakpoint. + What we check for is that 1) stepping is going on + and 2) the pc before the last insn does not match + the address of the breakpoint before the current pc + and 3) we didn't hit a breakpoint in a signal handler + without an intervening stop in sigtramp, which is + detected by a new stack pointer value below + any usual function calling stack adjustments. */ + (CURRENTLY_STEPPING () + && prev_pc != stop_pc - DECR_PC_AFTER_BREAK + && !(step_range_end + && INNER_THAN (read_sp (), (step_sp - 16)))) : + 0) + ); + /* Following in case break condition called a + function. */ + stop_print_frame = 1; + } + + if (stop_signal == TARGET_SIGNAL_TRAP) + random_signal + = !(bpstat_explains_signal (stop_bpstat) + || trap_expected +#ifndef CALL_DUMMY_BREAKPOINT_OFFSET + || PC_IN_CALL_DUMMY (stop_pc, read_sp (), + FRAME_FP (get_current_frame ())) +#endif /* No CALL_DUMMY_BREAKPOINT_OFFSET. */ + || (step_range_end && step_resume_breakpoint == NULL)); + + else + { + 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. */ +#ifndef CALL_DUMMY_BREAKPOINT_OFFSET + || PC_IN_CALL_DUMMY (stop_pc, read_sp (), + FRAME_FP (get_current_frame ())) +#endif /* No CALL_DUMMY_BREAKPOINT_OFFSET. */ + ); + if (!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 + 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 (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 (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 (w.kind == TARGET_WAITKIND_FORKED) + { + if (random_signal) /* I.e., no catchpoint triggered for this. */ + { + trap_expected = 1; + stop_signal = TARGET_SIGNAL_0; + goto keep_going; + } + } + else if (w.kind == TARGET_WAITKIND_VFORKED) + { + if (random_signal) /* I.e., no catchpoint triggered for this. */ + { + stop_signal = TARGET_SIGNAL_0; + goto keep_going; + } + } + else if (w.kind == TARGET_WAITKIND_EXECD) + { + pending_follow.kind = w.kind; + if (random_signal) /* I.e., no catchpoint triggered for this. */ + { + trap_expected = 1; + stop_signal = TARGET_SIGNAL_0; + goto keep_going; + } + } + + /* For the program's own signals, act according to + the signal handling tables. */ + + if (random_signal) + { + /* Signal not for debugging purposes. */ + int printed = 0; + + stopped_by_random_signal = 1; + + if (signal_print[stop_signal]) + { + printed = 1; + target_terminal_ours_for_output (); + annotate_signal (); + printf_filtered ("\nProgram received signal "); + annotate_signal_name (); + printf_filtered ("%s", target_signal_to_name (stop_signal)); + annotate_signal_name_end (); + printf_filtered (", "); + annotate_signal_string (); + printf_filtered ("%s", target_signal_to_string (stop_signal)); + annotate_signal_string_end (); + printf_filtered (".\n"); + gdb_flush (gdb_stdout); + } + if (signal_stop[stop_signal]) + break; + /* 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; + + /* If we're in the middle of a "next" command, let the code for + stepping over a function handle this. pai/1997-09-10 + + A previous comment here suggested it was possible to change + this to jump to keep_going in all cases. */ + + if (step_over_calls > 0) + goto step_over_function; + else + goto check_sigtramp2; + } + + /* Handle cases caused by hitting a breakpoint. */ + { + CORE_ADDR jmp_buf_pc; + struct bpstat_what what; + + what = bpstat_what (stop_bpstat); + + if (what.call_dummy) + { + stop_stack_dummy = 1; +#ifdef HP_OS_BUG + trap_expected_after_continue = 1; +#endif + } + + switch (what.main_action) + { + case BPSTAT_WHAT_SET_LONGJMP_RESUME: + /* If we hit the breakpoint at longjmp, disable it for the + duration of this command. Then, install a temporary + breakpoint at the target of the jmp_buf. */ + disable_longjmp_breakpoint (); + remove_breakpoints (); + breakpoints_inserted = 0; + if (!GET_LONGJMP_TARGET (&jmp_buf_pc)) + goto keep_going; + + /* Need to blow away step-resume breakpoint, as it + interferes with us */ + if (step_resume_breakpoint != NULL) + { + delete_breakpoint (step_resume_breakpoint); + step_resume_breakpoint = NULL; + } + /* Not sure whether we need to blow this away too, but probably + it is like the step-resume breakpoint. */ + if (through_sigtramp_breakpoint != NULL) + { + delete_breakpoint (through_sigtramp_breakpoint); + through_sigtramp_breakpoint = NULL; + } + +#if 0 + /* FIXME - Need to implement nested temporary breakpoints */ + if (step_over_calls > 0) + set_longjmp_resume_breakpoint (jmp_buf_pc, + get_current_frame ()); + else +#endif /* 0 */ + set_longjmp_resume_breakpoint (jmp_buf_pc, NULL); + handling_longjmp = 1; /* FIXME */ + goto keep_going; + + 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))) + { + another_trap = 1; + goto keep_going; + } +#endif /* 0 */ + disable_longjmp_breakpoint (); + handling_longjmp = 0; /* FIXME */ + if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME) + break; + /* else fallthrough */ + + case BPSTAT_WHAT_SINGLE: + if (breakpoints_inserted) + { + thread_step_needed = 1; + remove_breakpoints (); + } + breakpoints_inserted = 0; + 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. */ + + goto stop_stepping; + + 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. */ + + goto stop_stepping; + + 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. */ + if (step_resume_breakpoint == NULL) + { + step_resume_breakpoint = + bpstat_find_step_resume_breakpoint (stop_bpstat); + } + 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) + another_trap = 1; + break; + + case BPSTAT_WHAT_CHECK_SHLIBS: + case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK: +#ifdef SOLIB_ADD + { + extern int auto_solib_add; + + /* Remove breakpoints, we eventually want to step over the + shlib event breakpoint, and SOLIB_ADD might adjust + breakpoint addresses via breakpoint_re_set. */ + if (breakpoints_inserted) + remove_breakpoints (); + breakpoints_inserted = 0; + + /* Check for any newly added shared libraries if we're + supposed to be adding them automatically. */ + 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_print_frame = 0; + goto stop_stepping; + } + + /* 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, + &stepping_through_solib_catchpoints); + stepping_through_solib_after_catch = 1; + + /* Be sure to lift all breakpoints, so the inferior does + actually step past this point... */ + another_trap = 1; + break; + } + else + { + /* We want to step over this breakpoint, then keep going. */ + another_trap = 1; + break; + } + } +#endif + break; + + case BPSTAT_WHAT_LAST: + /* Not a real code, but listed here to shut up gcc -Wall. */ + + case BPSTAT_WHAT_KEEP_CHECKING: + break; + } + } + + /* We come here if we hit a breakpoint but should not + stop for it. Possibly we also were stepping + and should stop for that. So fall through and + test for stepping. But, if not stepping, + do not stop. */ + + /* Are we stepping to get the inferior out of the dynamic + linker's hook (and possibly the dld itself) after catching + a shlib event? */ + if (stepping_through_solib_after_catch) + { +#if defined(SOLIB_ADD) + /* Have we reached our destination? If not, keep going. */ + if (SOLIB_IN_DYNAMIC_LINKER (pid, stop_pc)) + { + another_trap = 1; + goto keep_going; + } +#endif + /* Else, stop and report the catchpoint(s) whose triggering + caused us to begin stepping. */ + stepping_through_solib_after_catch = 0; + bpstat_clear (&stop_bpstat); + stop_bpstat = bpstat_copy (stepping_through_solib_catchpoints); + bpstat_clear (&stepping_through_solib_catchpoints); + stop_print_frame = 1; + goto stop_stepping; + } + +#ifndef CALL_DUMMY_BREAKPOINT_OFFSET + /* 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; + } +#endif /* No CALL_DUMMY_BREAKPOINT_OFFSET. */ + + if (step_resume_breakpoint) + /* Having a step-resume breakpoint overrides anything + else having to do with stepping commands until + that breakpoint is reached. */ + /* I'm not sure whether this needs to be check_sigtramp2 or + whether it could/should be keep_going. */ + goto check_sigtramp2; + + 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. */ + goto check_sigtramp2; + + /* 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 +#if 0 +/* I haven't a clue what might trigger this clause, and it seems wrong + anyway, so I've disabled it until someone complains. -Stu 10/24/95 */ + + /* 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 + && FRAME_FP (get_current_frame ()) + && (INNER_THAN (read_sp (), step_sp) + || FRAME_FP (get_current_frame ()) != step_frame_address)) +#endif + ) + { + /* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal. + So definately need to check for sigtramp here. */ + goto check_sigtramp2; + } + + /* We stepped out of the stepping range. */ + + /* If we are stepping at the source level and entered the runtime + loader dynamic symbol resolution code, we keep on single stepping + until we exit the run time loader code and reach the callee's + address. */ + if (step_over_calls < 0 && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc)) + goto keep_going; + + /* We can't update step_sp every time through the loop, because + reading the stack pointer would slow down stepping too much. + But we can update it every time we leave the step range. */ + update_step_sp = 1; + + /* Did we just take a signal? */ + if (IN_SIGTRAMP (stop_pc, 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 */ + + + { + CORE_ADDR current_frame = FRAME_FP (get_current_frame ()); + + 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). */ + + /* 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. */ + step_resume_breakpoint = + set_momentary_breakpoint (sr_sal, NULL, bp_step_resume); + if (breakpoints_inserted) + insert_breakpoints (); + } + else + { + /* We just stepped out of a signal handler and into + its calling trampoline. + + Normally, we'd jump to 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, &stop_func_name, + &stop_func_start, + &stop_func_end); + /* Readjust stepping range */ + step_range_start = stop_func_start; + step_range_end = stop_func_end; + stepping_through_sigtramp = 1; + } + } + + + /* If this is stepi or nexti, make sure that the stepping range + gets us past that instruction. */ + if (step_range_end == 1) + /* FIXME: Does this run afoul of the code below which, if + we step into the middle of a line, resets the stepping + range? */ + step_range_end = (step_range_start = prev_pc) + 1; + + remove_breakpoints_on_following_step = 1; + goto keep_going; + } + +#if 0 + /* I disabled this test because it was too complicated and slow. + The SKIP_PROLOGUE was especially slow, because it caused + unnecessary prologue examination on various architectures. + The code in the #else clause has been tested on the Sparc, + Mips, PA, and Power architectures, so it's pretty likely to + be correct. -Stu 10/24/95 */ + + /* See if we left the step range due to a subroutine call that + we should proceed to the end of. */ + + if (stop_func_start) + { + struct symtab *s; + + /* Do this after the IN_SIGTRAMP check; it might give + an error. */ + prologue_pc = stop_func_start; + + /* Don't skip the prologue if this is assembly source */ + s = find_pc_symtab (stop_pc); + if (s && s->language != language_asm) + SKIP_PROLOGUE (prologue_pc); + } + + if (!(INNER_THAN (step_sp, read_sp ())) /* don't mistake (sig)return + as a call */ + && ( /* Might be a non-recursive call. If the symbols are missing + enough that stop_func_start == prev_func_start even though + they are really two functions, we will treat some calls as + jumps. */ + stop_func_start != prev_func_start + + /* Might be a recursive call if either we have a prologue + or the call instruction itself saves the PC on the stack. */ + || prologue_pc != stop_func_start + || read_sp () != step_sp) + && ( /* PC is completely out of bounds of any known objfiles. Treat + like a subroutine call. */ + !stop_func_start + + /* If we do a call, we will be at the start of a function... */ + || stop_pc == stop_func_start + + /* ...except on the Alpha with -O (and also Irix 5 and + perhaps others), in which we might call the address + after the load of gp. Since prologues don't contain + calls, we can't return to within one, and we don't + jump back into them, so this check is OK. */ + + || stop_pc < prologue_pc + + /* ...and if it is a leaf function, the prologue might + consist of gp loading only, so the call transfers to + the first instruction after the prologue. */ + || (stop_pc == prologue_pc + + /* Distinguish this from the case where we jump back + to the first instruction after the prologue, + within a function. */ + && stop_func_start != prev_func_start) + + /* If we end up in certain places, it means we did a subroutine + call. I'm not completely sure this is necessary now that we + have the above checks with stop_func_start (and now that + find_pc_partial_function is pickier). */ + || IN_SOLIB_CALL_TRAMPOLINE (stop_pc, stop_func_name) + + /* If none of the above apply, it is a jump within a function, + or a return from a subroutine. The other case is longjmp, + which can no longer happen here as long as the + handling_longjmp stuff is working. */ + )) +#else + /* This test is a much more streamlined, (but hopefully correct) + replacement for the code above. It's been tested on the Sparc, + Mips, PA, and Power architectures with good results. */ + + if (stop_pc == stop_func_start /* Quick test */ + || (in_prologue (stop_pc, stop_func_start) && + !IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, stop_func_name)) + || IN_SOLIB_CALL_TRAMPOLINE (stop_pc, stop_func_name) + || stop_func_name == 0) +#endif + + { + /* 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; + break; + } + + if (step_over_calls > 0 || IGNORE_HELPER_CALL (stop_pc)) + /* We're doing a "next". */ + goto step_over_function; + + /* 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) + 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); + step_resume_breakpoint = + set_momentary_breakpoint (xxx, NULL, bp_step_resume); + insert_breakpoints (); + goto keep_going; + } + } + + /* If we have line number information for the function we + are thinking of stepping into, step into it. + + If there are several symtabs at that PC (e.g. with include + files), just want to know whether *any* of them have line + numbers. find_pc_line handles this. */ + { + struct symtab_and_line tmp_sal; + + tmp_sal = find_pc_line (stop_func_start, 0); + if (tmp_sal.line != 0) + goto step_into_function; + } + + step_over_function: + /* A subroutine call has happened. */ + { + /* Set a special breakpoint after the return */ + struct symtab_and_line sr_sal; + + INIT_SAL (&sr_sal); + sr_sal.symtab = NULL; + sr_sal.line = 0; + + /* If we came here after encountering a signal in the middle of + a "next", use the stashed-away previous frame pc */ + sr_sal.pc + = stopped_by_random_signal + ? prev_pc + : ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ())); + + step_resume_breakpoint = + set_momentary_breakpoint (sr_sal, + stopped_by_random_signal ? + NULL : get_current_frame (), + bp_step_resume); + + /* We've just entered a callee, and we wish to resume until + it returns to the caller. Setting a step_resume bp on + the return PC 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 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). + + But ... don't do it if we're single-stepping out of a + sigtramp, because the reason we're single-stepping is + precisely because unwinding is a problem (HP-UX 10.20, + e.g.) and the frame address is likely to be incorrect. + No danger of sigtramp recursion. */ + + if (stepping_through_sigtramp) + { + step_resume_breakpoint->frame = (CORE_ADDR) NULL; + stepping_through_sigtramp = 0; + } + else if (!IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc)) + step_resume_breakpoint->frame = step_frame_address; + + if (breakpoints_inserted) + insert_breakpoints (); + } + goto keep_going; + + step_into_function: + /* Subroutine call with source code we should not step over. + Do step to the first line of code in it. */ + { + struct symtab *s; + + s = find_pc_symtab (stop_pc); + if (s && s->language != language_asm) + 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 (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 (sal.end && sal.pc != stop_func_start && sal.end < stop_func_end) + 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. */ + { + struct symtab_and_line sr_sal; + + INIT_SAL (&sr_sal); /* initialize to zeroes */ + sr_sal.pc = stop_func_start; + sr_sal.section = find_pc_overlay (stop_func_start); + /* Do not specify what the fp should be when we stop + since on some machines the prologue + is where the new fp value is established. */ + 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; + } + goto keep_going; + } + + /* We've wandered out of the step range. */ + + 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; + break; + } + + /* 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, 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. */ + 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. */ + goto keep_going; + } + } + + if (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; + break; + } + + if ((stop_pc == sal.pc) + && (current_line != sal.line || current_symtab != 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; + break; + } + + /* 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 (stop_func_end && sal.end >= 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; + break; + } + step_range_start = sal.pc; + step_range_end = sal.end; + step_frame_address = FRAME_FP (get_current_frame ()); + current_line = sal.line; + current_symtab = sal.symtab; + + /* 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; + } + + + goto keep_going; + + check_sigtramp2: + if (trap_expected + && IN_SIGTRAMP (stop_pc, 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 testsuite/gdb.t06/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 (); + + remove_breakpoints_on_following_step = 1; + another_trap = 1; + } + + keep_going: + /* Come to this label when you need to resume the inferior. + It's really much cleaner to do a goto than a maze of if-else + conditions. */ + + /* ??rehrauer: ttrace on HP-UX theoretically allows one to debug + a vforked child beetween 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 = 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; + + if (update_step_sp) + step_sp = read_sp (); + 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 (), 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 + && remove_breakpoints_on_following_step) + { + remove_breakpoints_on_following_step = 0; + remove_breakpoints (); + breakpoints_inserted = 0; + } + else if (!breakpoints_inserted && + (through_sigtramp_breakpoint != NULL || !another_trap)) + { + breakpoints_failed = insert_breakpoints (); + if (breakpoints_failed) + break; + breakpoints_inserted = 1; + } + + trap_expected = 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 (), stop_signal); + } + } + +stop_stepping: + 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) + { + int parent_pid; + + do + { + if (target_wait_hook) + parent_pid = target_wait_hook (-1, &w); + else + parent_pid = target_wait (-1, &w); + } + while (parent_pid != inferior_pid); + } + + + /* Assuming the inferior still exists, set these up for next + time, just like we did above if we didn't break out of the + loop. */ + prev_pc = read_pc (); + prev_func_start = stop_func_start; + prev_func_name = stop_func_name; + } + do_cleanups (old_cleanups); +} + +/* This function returns TRUE if ep is an internal breakpoint + set to catch generic shared library (aka dynamically-linked + library) events. (This is *NOT* the same as a catchpoint for a + shlib event. The latter is something a user can set; this is + something gdb sets for its own use, and isn't ever shown to a + user.) */ +static int +is_internal_shlib_eventpoint (ep) + struct breakpoint *ep; +{ + return + (ep->type == bp_shlib_event) + ; +} + +/* This function returns TRUE if bs indicates that the inferior + stopped due to a shared library (aka dynamically-linked library) + event. */ +static int +stopped_for_internal_shlib_event (bs) + bpstat bs; +{ + /* Note that multiple eventpoints may've caused the stop. Any + that are associated with shlib events will be accepted. */ + for (; bs != NULL; bs = bs->next) + { + if ((bs->breakpoint_at != NULL) + && is_internal_shlib_eventpoint (bs->breakpoint_at)) + return 1; + } + + /* If we get here, then no candidate was found. */ + return 0; +} + +/* This function returns TRUE if bs indicates that the inferior + stopped due to a shared library (aka dynamically-linked library) + event caught by a catchpoint. + + If TRUE, cp_p is set to point to the catchpoint. + + Else, the value of cp_p is undefined. */ +static int +stopped_for_shlib_catchpoint (bs, cp_p) + bpstat bs; + struct breakpoint **cp_p; +{ + /* Note that multiple eventpoints may've caused the stop. Any + that are associated with shlib events will be accepted. */ + *cp_p = NULL; + + for (; bs != NULL; bs = bs->next) + { + if ((bs->breakpoint_at != NULL) + && ep_is_shlib_catchpoint (bs->breakpoint_at)) + { + *cp_p = bs->breakpoint_at; + return 1; + } + } + + /* If we get here, then no candidate was found. */ + return 0; +} + + +/* Here to return control to GDB when the inferior stops for real. + Print appropriate messages, remove breakpoints, give terminal our modes. + + STOP_PRINT_FRAME nonzero means print the executing frame + (pc, function, args, file, line number and line text). + BREAKPOINTS_FAILED nonzero means stop was due to error + attempting to insert breakpoints. */ + +void +normal_stop () +{ + +#ifdef HPUXHPPA + /* 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 ((switched_from_inferior_pid != inferior_pid) && + target_has_execution) + { + target_terminal_ours_for_output (); + printf_filtered ("[Switched to %s]\n", + target_pid_or_tid_to_str (inferior_pid)); + switched_from_inferior_pid = inferior_pid; + } +#endif + + /* Make sure that the current_frame's pc is correct. This + is a correction for setting up the frame info before doing + DECR_PC_AFTER_BREAK */ + if (target_has_execution && get_current_frame ()) + (get_current_frame ())->pc = read_pc (); + + if (breakpoints_failed) + { + target_terminal_ours_for_output (); + print_sys_errmsg ("ptrace", breakpoints_failed); + printf_filtered ("Stopped; cannot insert breakpoints.\n\ +The same program may be running in another process.\n"); + } + + if (target_has_execution && breakpoints_inserted) + { + if (remove_breakpoints ()) + { + target_terminal_ours_for_output (); + printf_filtered ("Cannot remove breakpoints because "); + printf_filtered ("program is no longer writable.\n"); + printf_filtered ("It might be running in another process.\n"); + printf_filtered ("Further execution is probably impossible.\n"); + } + } + breakpoints_inserted = 0; + + /* Delete the breakpoint we stopped at, if it wants to be deleted. + Delete any breakpoint that is to be deleted at the next stop. */ + + breakpoint_auto_delete (stop_bpstat); + + /* If an auto-display called a function and that got a signal, + delete that auto-display to avoid an infinite recursion. */ + + if (stopped_by_random_signal) + disable_current_display (); + + /* Don't print a message if in the middle of doing a "step n" + operation for n > 1 */ + if (step_multi && stop_step) + goto done; + + target_terminal_ours (); + + /* Did we stop because the user set the stop_on_solib_events + variable? (If so, we report this as a generic, "Stopped due + to shlib event" message.) */ + if (stopped_for_internal_shlib_event (stop_bpstat)) + { + printf_filtered ("Stopped due to shared library event\n"); + } + + /* Look up the hook_stop and run it if it exists. */ + + if (stop_command && stop_command->hook) + { + catch_errors (hook_stop_stub, stop_command->hook, + "Error while running hook_stop:\n", RETURN_MASK_ALL); + } + + if (!target_has_stack) + { + + goto done; + } + + /* Select innermost stack frame - i.e., current frame is frame 0, + and current location is based on that. + Don't do this on return from a stack dummy routine, + or if the program has exited. */ + + if (!stop_stack_dummy) + { + select_frame (get_current_frame (), 0); + + /* 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) + { + int bpstat_ret; + int source_flag; + + bpstat_ret = bpstat_print (stop_bpstat); + /* bpstat_print() returned one of: + -1: Didn't print anything + 0: Printed preliminary "Breakpoint n, " message, desires + location tacked on + 1: Printed something, don't tack on location */ + + if (bpstat_ret == -1) + if (stop_step + && step_frame_address == FRAME_FP (get_current_frame ()) + && step_start_function == find_pc_function (stop_pc)) + source_flag = -1; /* finished step, just print source line */ + else + source_flag = 1; /* print location and source line */ + else if (bpstat_ret == 0) /* hit bpt, desire location */ + source_flag = 1; /* print location and source line */ + else /* bpstat_ret == 1, hit bpt, do not desire location */ + source_flag = -1; /* just print source line */ + + /* The behavior of this routine with respect to the source + flag is: + -1: Print only source line + 0: Print only location + 1: Print location and source line */ + show_and_print_stack_frame (selected_frame, -1, source_flag); + + /* Display the auto-display expressions. */ + do_displays (); + } + } + + /* Save the function value return registers, if we care. + We might be about to restore their previous contents. */ + if (proceed_to_finish) + read_register_bytes (0, stop_registers, REGISTER_BYTES); + + if (stop_stack_dummy) + { + /* Pop the empty frame that contains the stack dummy. + POP_FRAME ends with a setting of the current frame, so we + can use that next. */ + POP_FRAME; + /* 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 (cmd) + PTR cmd; +{ + execute_user_command ((struct cmd_list_element *) cmd, 0); + return (0); +} + +int +signal_stop_state (signo) + int signo; +{ + return signal_stop[signo]; +} + +int +signal_print_state (signo) + int signo; +{ + return signal_print[signo]; +} + +int +signal_pass_state (signo) + int signo; +{ + return signal_program[signo]; +} + +static void +sig_print_header () +{ + printf_filtered ("\ +Signal Stop\tPrint\tPass to program\tDescription\n"); +} + +static void +sig_print_info (oursig) + enum target_signal oursig; +{ + char *name = target_signal_to_name (oursig); + int name_padding = 13 - strlen (name); + if (name_padding <= 0) + name_padding = 0; + + printf_filtered ("%s", name); + printf_filtered ("%*.*s ", name_padding, name_padding, + " "); + printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No"); + printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No"); + printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No"); + printf_filtered ("%s\n", target_signal_to_string (oursig)); +} + +/* Specify how various signals in the inferior should be handled. */ + +static void +handle_command (args, from_tty) + char *args; + int from_tty; +{ + char **argv; + int digits, wordlen; + int sigfirst, signum, siglast; + enum target_signal oursig; + int allsigs; + int nsigs; + unsigned char *sigs; + struct cleanup *old_chain; + + if (args == NULL) + { + error_no_arg ("signal to handle"); + } + + /* Allocate and zero an array of flags for which signals to handle. */ + + nsigs = (int) TARGET_SIGNAL_LAST; + sigs = (unsigned char *) alloca (nsigs); + memset (sigs, 0, nsigs); + + /* Break the command line up into args. */ + + argv = buildargv (args); + if (argv == NULL) + { + nomem (0); + } + old_chain = make_cleanup ((make_cleanup_func) freeargv, (char *) argv); + + /* Walk through the args, looking for signal oursigs, signal names, and + actions. Signal numbers and signal names may be interspersed with + actions, with the actions being performed for all signals cumulatively + specified. Signal ranges can be specified as <LOW>-<HIGH>. */ + + while (*argv != NULL) + { + wordlen = strlen (*argv); + for (digits = 0; isdigit ((*argv)[digits]); digits++) + {; + } + allsigs = 0; + sigfirst = siglast = -1; + + if (wordlen >= 1 && !strncmp (*argv, "all", wordlen)) + { + /* Apply action to all signals except those used by the + debugger. Silently skip those. */ + allsigs = 1; + sigfirst = 0; + siglast = nsigs - 1; + } + else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen)) + { + SET_SIGS (nsigs, sigs, signal_stop); + SET_SIGS (nsigs, sigs, signal_print); + } + else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen)) + { + UNSET_SIGS (nsigs, sigs, signal_program); + } + else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen)) + { + SET_SIGS (nsigs, sigs, signal_print); + } + else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen)) + { + SET_SIGS (nsigs, sigs, signal_program); + } + else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen)) + { + UNSET_SIGS (nsigs, sigs, signal_stop); + } + else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen)) + { + SET_SIGS (nsigs, sigs, signal_program); + } + else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen)) + { + UNSET_SIGS (nsigs, sigs, signal_print); + UNSET_SIGS (nsigs, sigs, signal_stop); + } + else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen)) + { + UNSET_SIGS (nsigs, sigs, signal_program); + } + else if (digits > 0) + { + /* It is numeric. The numeric signal refers to our own + internal signal numbering from target.h, not to host/target + signal number. This is a feature; users really should be + using symbolic names anyway, and the common ones like + SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */ + + sigfirst = siglast = (int) + target_signal_from_command (atoi (*argv)); + if ((*argv)[digits] == '-') + { + siglast = (int) + target_signal_from_command (atoi ((*argv) + digits + 1)); + } + if (sigfirst > siglast) + { + /* Bet he didn't figure we'd think of this case... */ + signum = sigfirst; + sigfirst = siglast; + siglast = signum; + } + } + else + { + oursig = target_signal_from_name (*argv); + if (oursig != TARGET_SIGNAL_UNKNOWN) + { + sigfirst = siglast = (int) oursig; + } + else + { + /* Not a number and not a recognized flag word => complain. */ + error ("Unrecognized or ambiguous flag word: \"%s\".", *argv); + } + } + + /* If any signal numbers or symbol names were found, set flags for + which signals to apply actions to. */ + + for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++) + { + switch ((enum target_signal) signum) + { + case TARGET_SIGNAL_TRAP: + case TARGET_SIGNAL_INT: + if (!allsigs && !sigs[signum]) + { + if (query ("%s is used by the debugger.\n\ +Are you sure you want to change it? ", + target_signal_to_name + ((enum target_signal) signum))) + { + sigs[signum] = 1; + } + else + { + printf_unfiltered ("Not confirmed, unchanged.\n"); + gdb_flush (gdb_stdout); + } + } + break; + case TARGET_SIGNAL_0: + case TARGET_SIGNAL_DEFAULT: + case TARGET_SIGNAL_UNKNOWN: + /* Make sure that "all" doesn't print these. */ + break; + default: + sigs[signum] = 1; + break; + } + } + + argv++; + } + + target_notice_signals (inferior_pid); + + if (from_tty) + { + /* Show the results. */ + sig_print_header (); + for (signum = 0; signum < nsigs; signum++) + { + if (sigs[signum]) + { + sig_print_info (signum); + } + } + } + + do_cleanups (old_chain); +} + +static void +xdb_handle_command (args, from_tty) + 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 ((make_cleanup_func) freeargv, (char *) 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. + 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, from_tty) + char *signum_exp; + int from_tty; +{ + enum target_signal oursig; + sig_print_header (); + + if (signum_exp) + { + /* First see if this is a symbol name. */ + oursig = target_signal_from_name (signum_exp); + if (oursig == TARGET_SIGNAL_UNKNOWN) + { + /* No, try numeric. */ + oursig = + target_signal_from_command (parse_and_eval_address (signum_exp)); + } + sig_print_info (oursig); + return; + } + + printf_filtered ("\n"); + /* These ugly casts brought to you by the native VAX compiler. */ + for (oursig = TARGET_SIGNAL_FIRST; + (int) oursig < (int) TARGET_SIGNAL_LAST; + oursig = (enum target_signal) ((int) oursig + 1)) + { + QUIT; + + if (oursig != TARGET_SIGNAL_UNKNOWN + && oursig != TARGET_SIGNAL_DEFAULT + && oursig != TARGET_SIGNAL_0) + sig_print_info (oursig); + } + + printf_filtered ("\nUse the \"handle\" command to change these tables.\n"); +} + +/* Save all of the information associated with the inferior<==>gdb + connection. INF_STATUS is a pointer to a "struct inferior_status" + (defined in inferior.h). */ + +void +save_inferior_status (inf_status, restore_stack_info) + struct inferior_status *inf_status; + int restore_stack_info; +{ + inf_status->stop_signal = stop_signal; + inf_status->stop_pc = stop_pc; + inf_status->stop_step = stop_step; + inf_status->stop_stack_dummy = stop_stack_dummy; + inf_status->stopped_by_random_signal = stopped_by_random_signal; + inf_status->trap_expected = trap_expected; + inf_status->step_range_start = step_range_start; + inf_status->step_range_end = step_range_end; + inf_status->step_frame_address = step_frame_address; + inf_status->step_over_calls = step_over_calls; + inf_status->stop_after_trap = stop_after_trap; + inf_status->stop_soon_quietly = stop_soon_quietly; + /* Save original bpstat chain here; replace it with copy of chain. + If caller's caller is walking the chain, they'll be happier if we + hand them back the original chain when restore_i_s is called. */ + inf_status->stop_bpstat = stop_bpstat; + stop_bpstat = bpstat_copy (stop_bpstat); + inf_status->breakpoint_proceeded = breakpoint_proceeded; + inf_status->restore_stack_info = restore_stack_info; + inf_status->proceed_to_finish = proceed_to_finish; + + 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; +} + +struct restore_selected_frame_args +{ + CORE_ADDR frame_address; + int level; +}; + +static int restore_selected_frame PARAMS ((PTR)); + +/* Restore the selected frame. args is really a struct + restore_selected_frame_args * (declared as char * for catch_errors) + telling us what frame to restore. Returns 1 for success, or 0 for + failure. An error message will have been printed on error. */ + +static int +restore_selected_frame (args) + PTR args; +{ + 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); +} + +void +restore_inferior_status (inf_status) + struct inferior_status *inf_status; +{ + stop_signal = inf_status->stop_signal; + stop_pc = inf_status->stop_pc; + stop_step = inf_status->stop_step; + stop_stack_dummy = inf_status->stop_stack_dummy; + stopped_by_random_signal = inf_status->stopped_by_random_signal; + trap_expected = inf_status->trap_expected; + step_range_start = inf_status->step_range_start; + step_range_end = inf_status->step_range_end; + step_frame_address = inf_status->step_frame_address; + step_over_calls = inf_status->step_over_calls; + stop_after_trap = inf_status->stop_after_trap; + stop_soon_quietly = inf_status->stop_soon_quietly; + bpstat_clear (&stop_bpstat); + stop_bpstat = inf_status->stop_bpstat; + breakpoint_proceeded = inf_status->breakpoint_proceeded; + proceed_to_finish = inf_status->proceed_to_finish; + + 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 (target_has_execution) + write_register_bytes (0, inf_status->registers, REGISTER_BYTES); + + /* The inferior can be gone if the user types "print exit(0)" + (and perhaps other times). */ + + /* 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) + { + 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); + + } +} + + + +void +set_follow_fork_mode_command (arg, from_tty, c) + 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)); +} + + + +void +_initialize_infrun () +{ + register int i; + register int numsigs; + struct cmd_list_element *c; + + add_info ("signals", signals_info, + "What debugger does when program gets various signals.\n\ +Specify a signal as argument to print info on that signal only."); + add_info_alias ("handle", "signals", 0); + + add_com ("handle", class_run, handle_command, + concat ("Specify how to handle a signal.\n\ +Args are signals and actions to apply to those signals.\n\ +Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\ +from 1-15 are allowed for compatibility with old versions of GDB.\n\ +Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\ +The special arg \"all\" is recognized to mean all signals except those\n\ +used by the debugger, typically SIGTRAP and SIGINT.\n", + "Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\ +\"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\ +Stop means reenter debugger if this signal happens (implies print).\n\ +Print means print a message if this signal happens.\n\ +Pass means let program see this signal; otherwise program doesn't know.\n\ +Ignore is a synonym for nopass and noignore is a synonym for pass.\n\ +Pass and Stop may be combined.", NULL)); + if (xdb_commands) + { + add_com ("lz", class_info, signals_info, + "What debugger does when program gets various signals.\n\ +Specify a signal as argument to print info on that signal only."); + add_com ("z", class_run, xdb_handle_command, + concat ("Specify how to handle a signal.\n\ +Args are signals and actions to apply to those signals.\n\ +Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\ +from 1-15 are allowed for compatibility with old versions of GDB.\n\ +Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\ +The special arg \"all\" is recognized to mean all signals except those\n\ +used by the debugger, typically SIGTRAP and SIGINT.\n", + "Recognized actions include \"s\" (toggles between stop and nostop), \n\ +\"r\" (toggles between print and noprint), \"i\" (toggles between pass and \ +nopass), \"Q\" (noprint)\n\ +Stop means reenter debugger if this signal happens (implies print).\n\ +Print means print a message if this signal happens.\n\ +Pass means let program see this signal; otherwise program doesn't know.\n\ +Ignore is a synonym for nopass and noignore is a synonym for pass.\n\ +Pass and Stop may be combined.", NULL)); + } + + if (!dbx_commands) + stop_command = add_cmd ("stop", class_obscure, not_just_help_class_command, + "There is no `stop' command, but you can set a hook on `stop'.\n\ +This allows you to set a list of commands to be run each time execution\n\ +of the program stops.", &cmdlist); + + numsigs = (int) TARGET_SIGNAL_LAST; + signal_stop = (unsigned char *) + xmalloc (sizeof (signal_stop[0]) * numsigs); + signal_print = (unsigned char *) + xmalloc (sizeof (signal_print[0]) * numsigs); + signal_program = (unsigned char *) + xmalloc (sizeof (signal_program[0]) * numsigs); + for (i = 0; i < numsigs; i++) + { + signal_stop[i] = 1; + signal_print[i] = 1; + signal_program[i] = 1; + } + + /* Signals caused by debugger's own actions + should not be given to the program afterwards. */ + signal_program[TARGET_SIGNAL_TRAP] = 0; + signal_program[TARGET_SIGNAL_INT] = 0; + + /* Signals that are not errors should not normally enter the debugger. */ + signal_stop[TARGET_SIGNAL_ALRM] = 0; + signal_print[TARGET_SIGNAL_ALRM] = 0; + signal_stop[TARGET_SIGNAL_VTALRM] = 0; + signal_print[TARGET_SIGNAL_VTALRM] = 0; + signal_stop[TARGET_SIGNAL_PROF] = 0; + signal_print[TARGET_SIGNAL_PROF] = 0; + signal_stop[TARGET_SIGNAL_CHLD] = 0; + signal_print[TARGET_SIGNAL_CHLD] = 0; + signal_stop[TARGET_SIGNAL_IO] = 0; + signal_print[TARGET_SIGNAL_IO] = 0; + signal_stop[TARGET_SIGNAL_POLL] = 0; + signal_print[TARGET_SIGNAL_POLL] = 0; + signal_stop[TARGET_SIGNAL_URG] = 0; + signal_print[TARGET_SIGNAL_URG] = 0; + signal_stop[TARGET_SIGNAL_WINCH] = 0; + signal_print[TARGET_SIGNAL_WINCH] = 0; + +#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); +} |