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Text File | 1992-06-24 | 58.0 KB | 1,979 lines

head 1.1; branch ; access ; symbols ; locks ; strict; comment @ * @; 1.1 date 92.06.09.14.26.46; author secor; state Exp; branches ; next ; desc @@ 1.1 log @Initial revision @ text @/* Start (run) and stop the inferior process, for GDB. Copyright 1986, 1987, 1988, 1989, 1991, 1992 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* Notes on the algorithm used in wait_for_inferior to determine if we just did a subroutine call when stepping. We have the following information at that point: Current and previous (just before this step) pc. Current and previous sp. Current and previous start of current function. If the starts of the functions don't match, then a) We did a subroutine call. In this case, the pc will be at the beginning of a function. b) We did a subroutine return. Otherwise. c) We did a longjmp. If we did a longjump, we were doing "nexti", since a next would have attempted to skip over the assembly language routine in which the longjmp is coded and would have simply been the equivalent of a continue. I consider this ok behaivior. We'd like one of two things to happen if we are doing a nexti through the longjmp() routine: 1) It behaves as a stepi, or 2) It acts like a continue as above. Given that this is a special case, and that anybody who thinks that the concept of sub calls is meaningful in the context of a longjmp, I'll take either one. Let's see what happens. Acts like a subroutine return. I can handle that with no problem at all. -->So: If the current and previous beginnings of the current function don't match, *and* the pc is at the start of a function, we've done a subroutine call. If the pc is not at the start of a function, we *didn't* do a subroutine call. -->If the beginnings of the current and previous function do match, either: a) We just did a recursive call. In this case, we would be at the very beginning of a function and 1) it will have a prologue (don't jump to before prologue, or 2) (we assume here that it doesn't have a prologue) there will have been a change in the stack pointer over the last instruction. (Ie. it's got to put the saved pc somewhere. The stack is the usual place. In a recursive call a register is only an option if there's a prologue to do something with it. This is even true on register window machines; the prologue sets up the new window. It might not be true on a register window machine where the call instruction moved the register window itself. Hmmm. One would hope that the stack pointer would also change. If it doesn't, somebody send me a note, and I'll work out a more general theory. bug-gdb@@prep.ai.mit.edu). This is true (albeit slipperly so) on all machines I'm aware of: m68k: Call changes stack pointer. Regular jumps don't. sparc: Recursive calls must have frames and therefor, prologues. vax: All calls have frames and hence change the stack pointer. b) We did a return from a recursive call. I don't see that we have either the ability or the need to distinguish this from an ordinary jump. The stack frame will be printed when and if the frame pointer changes; if we are in a function without a frame pointer, it's the users own lookout. c) We did a jump within a function. We assume that this is true if we didn't do a recursive call. d) We are in no-man's land ("I see no symbols here"). We don't worry about this; it will make calls look like simple jumps (and the stack frames will be printed when the frame pointer moves), which is a reasonably non-violent response. */ #include "defs.h" #include <string.h> #include "symtab.h" #include "frame.h" #include "inferior.h" #include "breakpoint.h" #include "wait.h" #include "gdbcore.h" #include "signame.h" #include "command.h" #include "terminal.h" /* For #ifdef TIOCGPGRP and new_tty */ #include "target.h" #include <signal.h> /* unistd.h is needed to #define X_OK */ #ifdef USG #include <unistd.h> #else #include <sys/file.h> #endif #ifdef SET_STACK_LIMIT_HUGE #include <sys/time.h> #include <sys/resource.h> extern int original_stack_limit; #endif /* SET_STACK_LIMIT_HUGE */ /* Prototypes for local functions */ static void signals_info PARAMS ((char *, int)); static void handle_command PARAMS ((char *, int)); static void sig_print_info PARAMS ((int)); static void sig_print_header PARAMS ((void)); static void remove_step_breakpoint PARAMS ((void)); static void insert_step_breakpoint PARAMS ((void)); static void resume PARAMS ((int, int)); static void resume_cleanups PARAMS ((int)); extern char **environ; extern int sys_nerr; extern char *sys_errlist[]; extern struct target_ops child_ops; /* In inftarg.c */ /* Sigtramp is a routine that the kernel calls (which then calls the signal handler). On most machines it is a library routine that is linked into the executable. This macro, given a program counter value and the name of the function in which that PC resides (which can be null if the name is not known), returns nonzero if the PC and name show that we are in sigtramp. On most machines just see if the name is sigtramp (and if we have no name, assume we are not in sigtramp). */ #if !defined (IN_SIGTRAMP) #define IN_SIGTRAMP(pc, name) \ (name && !strcmp ("_sigtramp", name)) #endif /* 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 /* For SVR4 shared libraries, each call goes through a small piece of trampoline code in the ".init" section. IN_SOLIB_TRAMPOLINE evaluates to nonzero if we are current stopped in one of these. */ #ifndef IN_SOLIB_TRAMPOLINE #define IN_SOLIB_TRAMPOLINE(pc,name) 0 #endif /* Notify other parts of gdb that might care that signal handling may have changed for one or more signals. */ #ifndef NOTICE_SIGNAL_HANDLING_CHANGE #define NOTICE_SIGNAL_HANDLING_CHANGE /* No actions */ #endif #ifdef TDESC #include "tdesc.h" int safe_to_init_tdesc_context = 0; extern dc_dcontext_t current_context; #endif /* Tables of how to react to signals; the user sets them. */ static char signal_stop[NSIG]; static char signal_print[NSIG]; static char signal_program[NSIG]; /* Nonzero if breakpoints are now inserted in the inferior. */ /* Nonstatic for initialization during xxx_create_inferior. FIXME. */ /*static*/ int breakpoints_inserted; /* Function inferior was in as of last step command. */ static struct symbol *step_start_function; /* Nonzero => address for special breakpoint for resuming stepping. */ static CORE_ADDR step_resume_break_address; /* Pointer to orig contents of the byte where the special breakpoint is. */ static char step_resume_break_shadow[BREAKPOINT_MAX]; /* Nonzero means the special breakpoint is a duplicate so it has not itself been inserted. */ static int step_resume_break_duplicate; /* Nonzero if we are expecting a trace trap and should proceed from it. */ static int trap_expected; /* 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; /* 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 pc has been changed by the debugger since the inferior stopped. */ int pc_changed; /* 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; #ifdef NO_SINGLE_STEP extern int one_stepped; /* From machine dependent code */ extern void single_step (); /* Same. */ #endif /* NO_SINGLE_STEP */ /* Things to clean up if we QUIT out of resume (). */ /* ARGSUSED */ static void resume_cleanups (arg) int arg; { normal_stop (); } /* 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). */ static void resume (step, sig) int step; int sig; { struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0); QUIT; #ifdef NO_SINGLE_STEP if (step) { single_step(sig); /* Do it the hard way, w/temp breakpoints */ step = 0; /* ...and don't ask hardware to do it. */ } #endif /* Handle any optimized stores to the inferior NOW... */ #ifdef DO_DEFERRED_STORES DO_DEFERRED_STORES; #endif target_resume (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; step_resume_break_address = 0; 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; int 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. */ if (!pc_changed && breakpoint_here_p (read_pc ())) oneproc = 1; } else { write_register (PC_REGNUM, addr); #ifdef NPC_REGNUM write_register (NPC_REGNUM, addr + 4); #ifdef NNPC_REGNUM write_register (NNPC_REGNUM, addr + 8); #endif #endif } 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; } 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; } /* Install inferior's terminal modes. */ target_terminal_inferior (); if (siggnal >= 0) stop_signal = siggnal; /* If this signal should not be seen by program, give it zero. Used for debugging signals. */ else if (stop_signal < NSIG && !signal_program[stop_signal]) stop_signal= 0; /* 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_sp; static CORE_ADDR prev_func_start; static char *prev_func_name; /* Start an inferior Unix child process and sets inferior_pid to its pid. EXEC_FILE is the file to run. ALLARGS is a string containing the arguments to the program. ENV is the environment vector to pass. Errors reported with error(). */ #ifndef SHELL_FILE #define SHELL_FILE "/bin/sh" #endif void child_create_inferior (exec_file, allargs, env) char *exec_file; char *allargs; char **env; { int pid; char *shell_command; char *shell_file; static char default_shell_file[] = SHELL_FILE; int len; int pending_execs; /* Set debug_fork then attach to the child while it sleeps, to debug. */ static int debug_fork = 0; /* This is set to the result of setpgrp, which if vforked, will be visible to you in the parent process. It's only used by humans for debugging. */ static int debug_setpgrp = 657473; char **save_our_env; /* The user might want tilde-expansion, and in general probably wants the program to behave the same way as if run from his/her favorite shell. So we let the shell run it for us. FIXME, this should probably search the local environment (as modified by the setenv command), not the env gdb inherited. */ shell_file = getenv ("SHELL"); if (shell_file == NULL) shell_file = default_shell_file; len = 5 + strlen (exec_file) + 1 + strlen (allargs) + 1 + /*slop*/ 10; /* If desired, concat something onto the front of ALLARGS. SHELL_COMMAND is the result. */ #ifdef SHELL_COMMAND_CONCAT shell_command = (char *) alloca (strlen (SHELL_COMMAND_CONCAT) + len); strcpy (shell_command, SHELL_COMMAND_CONCAT); #else shell_command = (char *) alloca (len); shell_command[0] = '\0'; #endif strcat (shell_command, "exec "); #ifdef sprite strcat (shell_command, "debug "); #endif strcat (shell_command, exec_file); strcat (shell_command, " "); strcat (shell_command, allargs); /* exec is said to fail if the executable is open. */ close_exec_file (); /* Retain a copy of our environment variables, since the child will replace the value of environ and if we're vforked, we have to restore it. */ save_our_env = environ; /* Tell the terminal handling subsystem what tty we plan to run on; it will just record the information for later. */ new_tty_prefork (inferior_io_terminal); /* It is generally good practice to flush any possible pending stdio output prior to doing a fork, to avoid the possibility of both the parent and child flushing the same data after the fork. */ fflush (stdout); fflush (stderr); #ifdef sprite pid = fork(); #else #if defined(USG) && !defined(HAVE_VFORK) pid = fork (); #else if (debug_fork) pid = fork (); else pid = vfork (); #endif #endif if (pid < 0) perror_with_name ("vfork"); if (pid == 0) { if (debug_fork) sleep (debug_fork); #ifdef TIOCGPGRP /* Run inferior in a separate process group. */ #ifdef NEED_POSIX_SETPGID debug_setpgrp = setpgid (0, 0); #else #if defined(USG) && !defined(SETPGRP_ARGS) debug_setpgrp = setpgrp (); #else debug_setpgrp = setpgrp (getpid (), getpid ()); #endif /* USG */ #endif /* NEED_POSIX_SETPGID */ if (debug_setpgrp == -1) perror("setpgrp failed in child"); #endif /* TIOCGPGRP */ #ifdef SET_STACK_LIMIT_HUGE /* Reset the stack limit back to what it was. */ { struct rlimit rlim; getrlimit (RLIMIT_STACK, &rlim); rlim.rlim_cur = original_stack_limit; setrlimit (RLIMIT_STACK, &rlim); } #endif /* SET_STACK_LIMIT_HUGE */ /* Ask the tty subsystem to switch to the one we specified earlier (or to share the current terminal, if none was specified). */ new_tty (); /* Changing the signal handlers for the inferior after a vfork can also change them for the superior, so we don't mess with signals here. See comments in initialize_signals for how we get the right signal handlers for the inferior. */ #ifdef sprite /* * This appears to be needed on Sprite. */ signal (SIGQUIT, SIG_DFL); signal (SIGINT, SIG_DFL); #endif #ifdef USE_PROC_FS proc_set_exec_trap (); /* Use SVR4 /proc interface */ #else call_ptrace (0, 0, 0, 0); /* "Trace me, Dr. Memory!" */ #endif /* There is no execlpe call, so we have to set the environment for our child in the global variable. If we've vforked, this clobbers the parent, but environ is restored a few lines down in the parent. By the way, yes we do need to look down the path to find $SHELL. Rich Pixley says so, and I agree. */ environ = env; execlp (shell_file, shell_file, "-c", shell_command, (char *)0); fprintf (stderr, "Cannot exec %s: %s.\n", shell_file, errno < sys_nerr ? sys_errlist[errno] : "unknown error"); fflush (stderr); _exit (0177); } /* Restore our environment in case a vforked child clob'd it. */ environ = save_our_env; /* Now that we have a child process, make it our target. */ push_target (&child_ops); #ifdef CREATE_INFERIOR_HOOK CREATE_INFERIOR_HOOK (pid); #endif /* The process was started by the fork that created it, but it will have stopped one instruction after execing the shell. Here we must get it up to actual execution of the real program. */ inferior_pid = pid; /* Needed for wait_for_inferior stuff below */ clear_proceed_status (); /* We will get a trace trap after one instruction. Continue it automatically. Eventually (after shell does an exec) it will get another trace trap. Then insert breakpoints and continue. */ #ifdef START_INFERIOR_TRAPS_EXPECTED pending_execs = START_INFERIOR_TRAPS_EXPECTED; #else pending_execs = 2; #endif init_wait_for_inferior (); /* Set up the "saved terminal modes" of the inferior based on what modes we are starting it with. */ target_terminal_init (); /* Install inferior's terminal modes. */ target_terminal_inferior (); while (1) { stop_soon_quietly = 1; /* Make wait_for_inferior be quiet */ wait_for_inferior (); if (stop_signal != SIGTRAP) { /* Let shell child handle its own signals in its own way */ /* FIXME, what if child has exit()ed? Must exit loop somehow */ resume (0, stop_signal); } else { /* We handle SIGTRAP, however; it means child did an exec. */ if (0 == --pending_execs) break; resume (0, 0); /* Just make it go on */ } } stop_soon_quietly = 0; /* We are now in the child process of interest, having exec'd the correct program, and are poised at the first instruction of the new program. */ #ifdef SOLIB_CREATE_INFERIOR_HOOK SOLIB_CREATE_INFERIOR_HOOK (pid); #endif /* Should this perhaps just be a "proceed" call? FIXME */ insert_step_breakpoint (); breakpoints_failed = insert_breakpoints (); if (!breakpoints_failed) { breakpoints_inserted = 1; target_terminal_inferior(); /* Start the child program going on its first instruction, single- stepping if we need to. */ resume (bpstat_should_step (), 0); wait_for_inferior (); normal_stop (); } } /* Start remote-debugging of a machine over a serial link. */ void start_remote () { init_wait_for_inferior (); clear_proceed_status (); stop_soon_quietly = 1; trap_expected = 0; wait_for_inferior (); normal_stop (); } /* Initialize static vars when a new inferior begins. */ void init_wait_for_inferior () { /* These are meaningless until the first time through wait_for_inferior. */ prev_pc = 0; prev_sp = 0; prev_func_start = 0; prev_func_name = NULL; trap_expected_after_continue = 0; breakpoints_inserted = 0; mark_breakpoints_out (); stop_signal = 0; /* Don't confuse first call to proceed(). */ } /* Attach to process PID, then initialize for debugging it and wait for the trace-trap that results from attaching. */ void child_attach (args, from_tty) char *args; int from_tty; { char *exec_file; int pid; dont_repeat(); if (!args) error_no_arg ("process-id to attach"); #ifndef ATTACH_DETACH error ("Can't attach to a process on this machine."); #else #ifdef sprite /* * Since Sprite pids are displayed in hex the atoi doesn't work. We * allow the attach command to use any C expression. */ pid = value_as_long (evaluate_expression (parse_expression (args))); #else pid = atoi (args); #endif /* Sprite */ if (target_has_execution) { if (query ("A program is being debugged already. Kill it? ")) target_kill (); else error ("Inferior not killed."); } exec_file = (char *) get_exec_file (1); if (from_tty) { printf ("Attaching program: %s pid %d\n", exec_file, pid); fflush (stdout); } attach (pid); inferior_pid = pid; push_target (&child_ops); mark_breakpoints_out (); target_terminal_init (); clear_proceed_status (); stop_soon_quietly = 1; /*proceed (-1, 0, -2);*/ target_terminal_inferior (); wait_for_inferior (); #ifdef SOLIB_ADD SOLIB_ADD ((char *)0, from_tty, (struct target_ops *)0); #endif normal_stop (); #endif /* ATTACH_DETACH */ } /* Wait for control to return from inferior to debugger. If inferior gets a signal, we may decide to start it up again instead of returning. That is why there is a loop in this function. When this function actually returns it means the inferior should be left stopped and GDB should read more commands. */ void wait_for_inferior () { WAITTYPE w; int another_trap; int random_signal; CORE_ADDR stop_sp; CORE_ADDR stop_func_start; char *stop_func_name; CORE_ADDR prologue_pc, tmp; int stop_step_resume_break; struct symtab_and_line sal; int remove_breakpoints_on_following_step = 0; int current_line; int handling_longjmp = 0; /* FIXME */ sal = find_pc_line(prev_pc, 0); current_line = sal.line; while (1) { /* Clean up saved state that will become invalid. */ pc_changed = 0; flush_cached_frames (); registers_changed (); target_wait (&w); #ifdef SIGTRAP_STOP_AFTER_LOAD /* Somebody called load(2), and it gave us a "trap signal after load". Ignore it gracefully. */ SIGTRAP_STOP_AFTER_LOAD (w); #endif /* See if the process still exists; clean up if it doesn't. */ if (WIFEXITED (w)) { target_terminal_ours (); /* Must do this before mourn anyway */ if (WEXITSTATUS (w)) printf ("\nProgram exited with code 0%o.\n", (unsigned int)WEXITSTATUS (w)); else if (!batch_mode()) printf ("\nProgram exited normally.\n"); fflush (stdout); target_mourn_inferior (); #ifdef NO_SINGLE_STEP one_stepped = 0; #endif stop_print_frame = 0; break; } else if (!WIFSTOPPED (w)) { stop_print_frame = 0; stop_signal = WTERMSIG (w); target_terminal_ours (); /* Must do this before mourn anyway */ target_kill (); /* kill mourns as well */ #ifdef PRINT_RANDOM_SIGNAL printf ("\nProgram terminated: "); PRINT_RANDOM_SIGNAL (stop_signal); #else printf ("\nProgram terminated with signal %d, %s\n", stop_signal, stop_signal < NSIG ? sys_siglist[stop_signal] : "(undocumented)"); #endif printf ("The inferior process no longer exists.\n"); fflush (stdout); #ifdef NO_SINGLE_STEP one_stepped = 0; #endif break; } #ifdef NO_SINGLE_STEP if (one_stepped) single_step (0); /* This actually cleans up the ss */ #endif /* NO_SINGLE_STEP */ stop_pc = read_pc (); set_current_frame ( create_new_frame (read_register (FP_REGNUM), read_pc ())); stop_frame_address = FRAME_FP (get_current_frame ()); stop_sp = read_register (SP_REGNUM); stop_func_start = 0; stop_func_name = 0; /* Don't care about return value; stop_func_start and stop_func_name will both be 0 if it doesn't work. */ (void) find_pc_partial_function (stop_pc, &stop_func_name, &stop_func_start); stop_func_start += FUNCTION_START_OFFSET; another_trap = 0; bpstat_clear (&stop_bpstat); stop_step = 0; stop_stack_dummy = 0; stop_print_frame = 1; stop_step_resume_break = 0; random_signal = 0; stopped_by_random_signal = 0; breakpoints_failed = 0; /* Look at the cause of the stop, and decide what to do. The alternatives are: 1) break; to really stop and return to the debugger, 2) drop through to start up again (set another_trap to 1 to single step once) 3) set random_signal to 1, and the decision between 1 and 2 will be made according to the signal handling tables. */ stop_signal = WSTOPSIG (w); /* First, distinguish signals caused by the debugger from signals that have to do with the program's own actions. Note that breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending on the operating system version. Here we detect when a SIGILL or SIGEMT is really a breakpoint and change it to SIGTRAP. */ if (stop_signal == SIGTRAP || (breakpoints_inserted && (stop_signal == SIGILL || stop_signal == SIGEMT)) || stop_soon_quietly) { if (stop_signal == SIGTRAP && stop_after_trap) { stop_print_frame = 0; break; } if (stop_soon_quietly) break; /* Don't even think about breakpoints if just proceeded over a breakpoint. However, if we are trying to proceed over a breakpoint and end up in sigtramp, then step_resume_break_address will be set and we should check whether we've hit the step breakpoint. */ if (stop_signal == SIGTRAP && trap_expected && step_resume_break_address == 0) bpstat_clear (&stop_bpstat); else { /* See if there is a breakpoint at the current PC. */ #if DECR_PC_AFTER_BREAK /* Notice the case of stepping through a jump that lands just after a breakpoint. Don't confuse that with hitting the breakpoint. What we check for is that 1) stepping is going on and 2) the pc before the last insn does not match the address of the breakpoint before the current pc. */ if (prev_pc == stop_pc - DECR_PC_AFTER_BREAK || !step_range_end || step_resume_break_address || handling_longjmp /* FIXME */) #endif /* DECR_PC_AFTER_BREAK not zero */ { /* See if we stopped at the special breakpoint for stepping over a subroutine call. If both are zero, this wasn't the reason for the stop. */ if (step_resume_break_address && stop_pc - DECR_PC_AFTER_BREAK == step_resume_break_address) { stop_step_resume_break = 1; if (DECR_PC_AFTER_BREAK) { stop_pc -= DECR_PC_AFTER_BREAK; write_register (PC_REGNUM, stop_pc); pc_changed = 0; } } else { stop_bpstat = bpstat_stop_status (&stop_pc, stop_frame_address); /* Following in case break condition called a function. */ stop_print_frame = 1; } } } if (stop_signal == SIGTRAP) random_signal = !(bpstat_explains_signal (stop_bpstat) || trap_expected || stop_step_resume_break || PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address) || (step_range_end && !step_resume_break_address)); else { random_signal = !(bpstat_explains_signal (stop_bpstat) || stop_step_resume_break /* End of a stack dummy. Some systems (e.g. Sony news) give another signal besides SIGTRAP, so check here as well as above. */ || PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address) ); if (!random_signal) stop_signal = SIGTRAP; } } else random_signal = 1; /* For the program's own signals, act according to the signal handling tables. */ if (random_signal) { /* Signal not for debugging purposes. */ int printed = 0; stopped_by_random_signal = 1; if (stop_signal >= NSIG || signal_print[stop_signal]) { printed = 1; target_terminal_ours_for_output (); #ifdef PRINT_RANDOM_SIGNAL PRINT_RANDOM_SIGNAL (stop_signal); #else printf ("\nProgram received signal %d, %s\n", stop_signal, stop_signal < NSIG ? sys_siglist[stop_signal] : "(undocumented)"); #endif /* PRINT_RANDOM_SIGNAL */ fflush (stdout); } if (stop_signal >= NSIG || signal_stop[stop_signal]) break; /* If not going to stop, give terminal back if we took it away. */ else if (printed) target_terminal_inferior (); /* Note that virtually all the code below does `if !random_signal'. Perhaps this code should end with a goto or continue. At least one (now fixed) bug was caused by this -- a !random_signal was missing in one of the tests below. */ } /* Handle cases caused by hitting a breakpoint. */ if (!random_signal) if (bpstat_explains_signal (stop_bpstat)) { CORE_ADDR jmp_buf_pc; switch (stop_bpstat->breakpoint_at->type) /* FIXME */ { /* If we hit the breakpoint at longjmp, disable it for the duration of this command. Then, install a temporary breakpoint at the target of the jmp_buf. */ case bp_longjmp: disable_longjmp_breakpoint(); remove_breakpoints (); breakpoints_inserted = 0; if (!GET_LONGJMP_TARGET(&jmp_buf_pc)) goto keep_going; /* Need to blow away step-resume breakpoint, as it interferes with us */ remove_step_breakpoint (); step_resume_break_address = 0; stop_step_resume_break = 0; #if 0 /* FIXME - Need to implement nested temporary breakpoints */ if (step_over_calls > 0) set_longjmp_resume_breakpoint(jmp_buf_pc, get_current_frame()); else #endif /* 0 */ set_longjmp_resume_breakpoint(jmp_buf_pc, NULL); handling_longjmp = 1; /* FIXME */ goto keep_going; case bp_longjmp_resume: remove_breakpoints (); breakpoints_inserted = 0; #if 0 /* FIXME - Need to implement nested temporary breakpoints */ if (step_over_calls && (stop_frame_address INNER_THAN step_frame_address)) { another_trap = 1; goto keep_going; } #endif /* 0 */ disable_longjmp_breakpoint(); handling_longjmp = 0; /* FIXME */ break; default: fprintf(stderr, "Unknown breakpoint type %d\n", stop_bpstat->breakpoint_at->type); case bp_watchpoint: case bp_breakpoint: case bp_until: case bp_finish: /* Does a breakpoint want us to stop? */ if (bpstat_stop (stop_bpstat)) { stop_print_frame = bpstat_should_print (stop_bpstat); goto stop_stepping; } /* Otherwise, must remove breakpoints and single-step to get us past the one we hit. */ else { remove_breakpoints (); remove_step_breakpoint (); breakpoints_inserted = 0; another_trap = 1; } break; } } else if (stop_step_resume_break) { /* But if we have hit the step-resumption breakpoint, remove it. It has done its job getting us here. The sp test is to make sure that we don't get hung up in recursive calls in functions without frame pointers. If the stack pointer isn't outside of where the breakpoint was set (within a routine to be stepped over), we're in the middle of a recursive call. Not true for reg window machines (sparc) because the must change frames to call things and the stack pointer doesn't have to change if it the bp was set in a routine without a frame (pc can be stored in some other window). The removal of the sp test is to allow calls to alloca. Nasty things were happening. Oh, well, gdb can only handle one level deep of lack of frame pointer. */ /* Disable test for step_frame_address match so that we always stop even if the frames don't match. Reason: if we hit the step_resume_breakpoint, there is no way to temporarily disable it so that we can step past it. If we leave the breakpoint in, then we loop forever repeatedly hitting, but never getting past the breakpoint. This change keeps nexting over recursive function calls from hanging gdb. */ #if 0 if (* step_frame_address == 0 || (step_frame_address == stop_frame_address)) #endif { remove_step_breakpoint (); step_resume_break_address = 0; /* If were waiting for a trap, hitting the step_resume_break doesn't count as getting it. */ if (trap_expected) another_trap = 1; } } /* We come here if we hit a breakpoint but should not stop for it. Possibly we also were stepping and should stop for that. So fall through and test for stepping. But, if not stepping, do not stop. */ /* If this is the breakpoint at the end of a stack dummy, just stop silently. */ if (!random_signal && PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address)) { stop_print_frame = 0; stop_stack_dummy = 1; #ifdef HP_OS_BUG trap_expected_after_continue = 1; #endif break; } if (step_resume_break_address) /* Having a step-resume breakpoint overrides anything else having to do with stepping commands until that breakpoint is reached. */ ; /* If stepping through a line, keep going if still within it. */ else if (!random_signal && step_range_end && stop_pc >= step_range_start && stop_pc < step_range_end /* The step range might include the start of the function, so if we are at the start of the step range and either the stack or frame pointers just changed, we've stepped outside */ && !(stop_pc == step_range_start && stop_frame_address && (stop_sp INNER_THAN prev_sp || stop_frame_address != step_frame_address))) { ; } /* We stepped out of the stepping range. See if that was due to a subroutine call that we should proceed to the end of. */ else if (!random_signal && step_range_end) { if (stop_func_start) { prologue_pc = stop_func_start; SKIP_PROLOGUE (prologue_pc); } /* Did we just take a signal? */ if (IN_SIGTRAMP (stop_pc, stop_func_name) && !IN_SIGTRAMP (prev_pc, prev_func_name)) { /* This code is needed at least in the following case: The user types "next" and then a signal arrives (before the "next" is done). */ /* We've just taken a signal; go until we are back to the point where we took it and one more. */ step_resume_break_address = prev_pc; step_resume_break_duplicate = breakpoint_here_p (step_resume_break_address); if (breakpoints_inserted) insert_step_breakpoint (); /* Make sure that the stepping range gets us past that instruction. */ if (step_range_end == 1) step_range_end = (step_range_start = prev_pc) + 1; remove_breakpoints_on_following_step = 1; goto save_pc; } /* ==> See comments at top of file on this algorithm. <==*/ if ((stop_pc == stop_func_start || IN_SOLIB_TRAMPOLINE (stop_pc, stop_func_name)) && (stop_func_start != prev_func_start || prologue_pc != stop_func_start || stop_sp != prev_sp)) { /* It's a subroutine call. (0) If we are not stepping over any calls ("stepi"), we just stop. (1) If we're doing a "next", we want to continue through the call ("step over the call"). (2) If we are in a function-call trampoline (a stub between the calling routine and the real function), locate the real function and change stop_func_start. (3) If we're doing a "step", and there are no debug symbols at the target of the call, we want to continue through it ("step over the call"). (4) Otherwise, we want to stop soon, after the function prologue ("step into the call"). */ if (step_over_calls == 0) { /* I presume that step_over_calls is only 0 when we're supposed to be stepping at the assembly language level. */ stop_step = 1; break; } if (step_over_calls > 0) goto step_over_function; tmp = SKIP_TRAMPOLINE_CODE (stop_pc); if (tmp != 0) stop_func_start = tmp; if (find_pc_function (stop_func_start) != 0) goto step_into_function; step_over_function: /* A subroutine call has happened. */ /* Set a special breakpoint after the return */ step_resume_break_address = ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ())); step_resume_break_duplicate = breakpoint_here_p (step_resume_break_address); if (breakpoints_inserted) insert_step_breakpoint (); goto save_pc; step_into_function: /* Subroutine call with source code we should not step over. Do step to the first line of code in it. */ SKIP_PROLOGUE (stop_func_start); sal = find_pc_line (stop_func_start, 0); /* Use the step_resume_break to step until the end of the prologue, even if that involves jumps (as it seems to on the vax under 4.2). */ /* If the prologue ends in the middle of a source line, continue to the end of that source line. Otherwise, just go to end of prologue. */ #ifdef PROLOGUE_FIRSTLINE_OVERLAP /* no, don't either. It skips any code that's legitimately on the first line. */ #else if (sal.end && sal.pc != stop_func_start) stop_func_start = sal.end; #endif if (stop_func_start == stop_pc) { /* We are already there: stop now. */ stop_step = 1; break; } else /* Put the step-breakpoint there and go until there. */ { step_resume_break_address = stop_func_start; step_resume_break_duplicate = breakpoint_here_p (step_resume_break_address); if (breakpoints_inserted) insert_step_breakpoint (); /* Do not specify what the fp should be when we stop since on some machines the prologue is where the new fp value is established. */ step_frame_address = 0; /* And make sure stepping stops right away then. */ step_range_end = step_range_start; } goto save_pc; } /* We've wandered out of the step range (but haven't done a subroutine call or return). */ sal = find_pc_line(stop_pc, 0); if (step_range_end == 1 || /* stepi or nexti */ sal.line == 0 || /* ...or no line # info */ (stop_pc == sal.pc /* ...or we're at the start */ && current_line != sal.line)) { /* of a different line */ /* Stop because we're done stepping. */ stop_step = 1; break; } else { /* We aren't done stepping, and we have line number info for $pc. Optimize by setting the step_range for the line. (We might not be in the original line, but if we entered a new line in mid-statement, we continue stepping. This makes things like for(;;) statements work better.) */ step_range_start = sal.pc; step_range_end = sal.end; goto save_pc; } /* We never fall through here */ } if (trap_expected && IN_SIGTRAMP (stop_pc, stop_func_name) && !IN_SIGTRAMP (prev_pc, prev_func_name)) { /* What has happened here is that we have just stepped the inferior with a signal (because it is a signal which shouldn't make us stop), thus stepping into sigtramp. So we need to set a step_resume_break_address breakpoint and continue until we hit it, and then step. */ step_resume_break_address = prev_pc; /* Always 1, I think, but it's probably easier to have the step_resume_break as usual rather than trying to re-use the breakpoint which is already there. */ step_resume_break_duplicate = breakpoint_here_p (step_resume_break_address); if (breakpoints_inserted) insert_step_breakpoint (); remove_breakpoints_on_following_step = 1; another_trap = 1; } /* My apologies to the gods of structured programming. */ /* Come to this label when you need to resume the inferior. It's really much cleaner at this time to do a goto than to try and figure out what the if-else chain ought to look like!! */ keep_going: save_pc: /* Save the pc before execution, to compare with pc after stop. */ prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */ prev_func_start = stop_func_start; /* Ok, since if DECR_PC_AFTER BREAK is defined, the original pc would not have been at the start of a function. */ prev_func_name = stop_func_name; prev_sp = stop_sp; /* If we did not do break;, it means we should keep running the inferior and not return to debugger. */ if (trap_expected && stop_signal != SIGTRAP) { /* We took a signal (which we are supposed to pass through to the inferior, else we'd have done a break above) and we haven't yet gotten our trap. Simply continue. */ resume ((step_range_end && !step_resume_break_address) || (trap_expected && !step_resume_break_address) || bpstat_should_step (), stop_signal); } else { /* Either the trap was not expected, but we are continuing anyway (the user asked that this signal be passed to the child) -- or -- The signal was SIGTRAP, e.g. it was our signal, but we decided we should resume from it. We're going to run this baby now! Insert breakpoints now, unless we are trying to one-proceed past a breakpoint. */ /* If we've just finished a special step resume and we don't want to hit a breakpoint, pull em out. */ if (!step_resume_break_address && remove_breakpoints_on_following_step) { remove_breakpoints_on_following_step = 0; remove_breakpoints (); breakpoints_inserted = 0; } else if (!breakpoints_inserted && (step_resume_break_address != 0 || !another_trap)) { insert_step_breakpoint (); breakpoints_failed = insert_breakpoints (); if (breakpoints_failed) break; breakpoints_inserted = 1; } trap_expected = another_trap; if (stop_signal == SIGTRAP) stop_signal = 0; #ifdef SHIFT_INST_REGS /* I'm not sure when this following segment applies. I do know, now, that we shouldn't rewrite the regs when we were stopped by a random signal from the inferior process. */ if (!bpstat_explains_signal (stop_bpstat) && (stop_signal != SIGCLD) && !stopped_by_random_signal) { CORE_ADDR pc_contents = read_register (PC_REGNUM); CORE_ADDR npc_contents = read_register (NPC_REGNUM); if (pc_contents != npc_contents) { write_register (NNPC_REGNUM, npc_contents); write_register (NPC_REGNUM, pc_contents); } } #endif /* SHIFT_INST_REGS */ resume ((!step_resume_break_address && !handling_longjmp && (step_range_end || trap_expected)) || bpstat_should_step (), stop_signal); } } stop_stepping: if (target_has_execution) { /* Assuming the inferior still exists, set these up for next time, just like we did above if we didn't break out of the loop. */ prev_pc = read_pc (); prev_func_start = stop_func_start; prev_func_name = stop_func_name; prev_sp = stop_sp; } } /* Here to return control to GDB when the inferior stops for real. Print appropriate messages, remove breakpoints, give terminal our modes. STOP_PRINT_FRAME nonzero means print the executing frame (pc, function, args, file, line number and line text). BREAKPOINTS_FAILED nonzero means stop was due to error attempting to insert breakpoints. */ void normal_stop () { /* Make sure that the current_frame's pc is correct. This is a correction for setting up the frame info before doing DECR_PC_AFTER_BREAK */ if (target_has_execution) (get_current_frame ())->pc = read_pc (); if (breakpoints_failed) { target_terminal_ours_for_output (); print_sys_errmsg ("ptrace", breakpoints_failed); printf ("Stopped; cannot insert breakpoints.\n\ The same program may be running in another process.\n"); } if (target_has_execution) remove_step_breakpoint (); if (target_has_execution && breakpoints_inserted) if (remove_breakpoints ()) { target_terminal_ours_for_output (); printf ("Cannot remove breakpoints because program is no longer writable.\n\ It might be running in another process.\n\ Further execution is probably impossible.\n"); } breakpoints_inserted = 0; /* Delete the breakpoint we stopped at, if it wants to be deleted. Delete any breakpoint that is to be deleted at the next stop. */ breakpoint_auto_delete (stop_bpstat); /* If an auto-display called a function and that got a signal, delete that auto-display to avoid an infinite recursion. */ if (stopped_by_random_signal) disable_current_display (); if (step_multi && stop_step) return; target_terminal_ours (); if (!target_has_stack) return; /* Select innermost stack frame except on return from a stack dummy routine, or if the program has exited. Print it without a level number if we have changed functions or hit a breakpoint. Print source line if we have one. */ if (!stop_stack_dummy) { select_frame (get_current_frame (), 0); if (stop_print_frame) { int source_only; source_only = bpstat_print (stop_bpstat); source_only = source_only || ( stop_step && step_frame_address == stop_frame_address && step_start_function == find_pc_function (stop_pc)); print_stack_frame (selected_frame, -1, source_only? -1: 1); /* Display the auto-display expressions. */ do_displays (); } } /* Save the function value return registers, if we care. We might be about to restore their previous contents. */ if (proceed_to_finish) read_register_bytes (0, stop_registers, REGISTER_BYTES); if (stop_stack_dummy) { /* Pop the empty frame that contains the stack dummy. POP_FRAME ends with a setting of the current frame, so we can use that next. */ POP_FRAME; select_frame (get_current_frame (), 0); } } static void insert_step_breakpoint () { if (step_resume_break_address && !step_resume_break_duplicate) target_insert_breakpoint (step_resume_break_address, step_resume_break_shadow); } static void remove_step_breakpoint () { if (step_resume_break_address && !step_resume_break_duplicate) target_remove_breakpoint (step_resume_break_address, step_resume_break_shadow); } int signal_stop_state (signo) int signo; { return ((signo >= 0 && signo < NSIG) ? signal_stop[signo] : 0); } int signal_print_state (signo) int signo; { return ((signo >= 0 && signo < NSIG) ? signal_print[signo] : 0); } int signal_pass_state (signo) int signo; { return ((signo >= 0 && signo < NSIG) ? signal_program[signo] : 0); } static void sig_print_header () { printf_filtered ("Signal\t\tStop\tPrint\tPass to program\tDescription\n"); } static void sig_print_info (number) int number; { char *abbrev = sig_abbrev(number); if (abbrev == NULL) printf_filtered ("%d\t\t", number); else printf_filtered ("SIG%s (%d)\t", abbrev, number); printf_filtered ("%s\t", signal_stop[number] ? "Yes" : "No"); printf_filtered ("%s\t", signal_print[number] ? "Yes" : "No"); printf_filtered ("%s\t\t", signal_program[number] ? "Yes" : "No"); printf_filtered ("%s\n", sys_siglist[number]); } /* Specify how various signals in the inferior should be handled. */ static void handle_command (args, from_tty) char *args; int from_tty; { register char *p = args; int signum = 0; register int digits, wordlen; char *nextarg; if (!args) error_no_arg ("signal to handle"); while (*p) { /* Find the end of the next word in the args. */ for (wordlen = 0; p[wordlen] && p[wordlen] != ' ' && p[wordlen] != '\t'; wordlen++); /* Set nextarg to the start of the word after the one we just found, and null-terminate this one. */ if (p[wordlen] == '\0') nextarg = p + wordlen; else { p[wordlen] = '\0'; nextarg = p + wordlen + 1; } for (digits = 0; p[digits] >= '0' && p[digits] <= '9'; digits++); if (signum == 0) { /* It is the first argument--must be the signal to operate on. */ if (digits == wordlen) { /* Numeric. */ signum = atoi (p); if (signum <= 0 || signum >= NSIG) { p[wordlen] = '\0'; error ("Invalid signal %s given as argument to \"handle\".", p); } } else { /* Symbolic. */ signum = sig_number (p); if (signum == -1) error ("No such signal \"%s\"", p); } if (signum == SIGTRAP || signum == SIGINT) { if (!query ("SIG%s is used by the debugger.\nAre you sure you want to change it? ", sig_abbrev (signum))) error ("Not confirmed."); } } /* Else, if already got a signal number, look for flag words saying what to do for it. */ else if (!strncmp (p, "stop", wordlen)) { signal_stop[signum] = 1; signal_print[signum] = 1; } else if (wordlen >= 2 && !strncmp (p, "print", wordlen)) signal_print[signum] = 1; else if (wordlen >= 2 && !strncmp (p, "pass", wordlen)) signal_program[signum] = 1; else if (!strncmp (p, "ignore", wordlen)) signal_program[signum] = 0; else if (wordlen >= 3 && !strncmp (p, "nostop", wordlen)) signal_stop[signum] = 0; else if (wordlen >= 4 && !strncmp (p, "noprint", wordlen)) { signal_print[signum] = 0; signal_stop[signum] = 0; } else if (wordlen >= 4 && !strncmp (p, "nopass", wordlen)) signal_program[signum] = 0; else if (wordlen >= 3 && !strncmp (p, "noignore", wordlen)) signal_program[signum] = 1; /* Not a number and not a recognized flag word => complain. */ else { error ("Unrecognized or ambiguous flag word: \"%s\".", p); } /* Find start of next word. */ p = nextarg; while (*p == ' ' || *p == '\t') p++; } NOTICE_SIGNAL_HANDLING_CHANGE; if (from_tty) { /* Show the results. */ sig_print_header (); sig_print_info (signum); } } /* Print current contents of the tables set by the handle command. */ static void signals_info (signum_exp, from_tty) char *signum_exp; int from_tty; { register int i; sig_print_header (); if (signum_exp) { /* First see if this is a symbol name. */ i = sig_number (signum_exp); if (i == -1) { /* Nope, maybe it's an address which evaluates to a signal number. */ i = parse_and_eval_address (signum_exp); if (i >= NSIG || i < 0) error ("Signal number out of bounds."); } sig_print_info (i); return; } printf_filtered ("\n"); for (i = 0; i < NSIG; i++) { QUIT; sig_print_info (i); } printf_filtered ("\nUse the \"handle\" command to change these tables.\n"); } /* Save all of the information associated with the inferior<==>gdb connection. INF_STATUS is a pointer to a "struct inferior_status" (defined in inferior.h). */ void save_inferior_status (inf_status, restore_stack_info) struct inferior_status *inf_status; int restore_stack_info; { inf_status->pc_changed = pc_changed; inf_status->stop_signal = stop_signal; inf_status->stop_pc = stop_pc; inf_status->stop_frame_address = stop_frame_address; inf_status->stop_step = stop_step; inf_status->stop_stack_dummy = stop_stack_dummy; inf_status->stopped_by_random_signal = stopped_by_random_signal; inf_status->trap_expected = trap_expected; inf_status->step_range_start = step_range_start; inf_status->step_range_end = step_range_end; inf_status->step_frame_address = step_frame_address; inf_status->step_over_calls = step_over_calls; inf_status->step_resume_break_address = step_resume_break_address; inf_status->stop_after_trap = stop_after_trap; inf_status->stop_soon_quietly = stop_soon_quietly; /* Save original bpstat chain here; replace it with copy of chain. If caller's caller is walking the chain, they'll be happier if we hand them back the original chain when restore_i_s is called. */ inf_status->stop_bpstat = stop_bpstat; stop_bpstat = bpstat_copy (stop_bpstat); inf_status->breakpoint_proceeded = breakpoint_proceeded; inf_status->restore_stack_info = restore_stack_info; inf_status->proceed_to_finish = proceed_to_finish; bcopy (stop_registers, inf_status->stop_registers, REGISTER_BYTES); record_selected_frame (&(inf_status->selected_frame_address), &(inf_status->selected_level)); return; } void restore_inferior_status (inf_status) struct inferior_status *inf_status; { FRAME fid; int level = inf_status->selected_level; pc_changed = inf_status->pc_changed; stop_signal = inf_status->stop_signal; stop_pc = inf_status->stop_pc; stop_frame_address = inf_status->stop_frame_address; stop_step = inf_status->stop_step; stop_stack_dummy = inf_status->stop_stack_dummy; stopped_by_random_signal = inf_status->stopped_by_random_signal; trap_expected = inf_status->trap_expected; step_range_start = inf_status->step_range_start; step_range_end = inf_status->step_range_end; step_frame_address = inf_status->step_frame_address; step_over_calls = inf_status->step_over_calls; step_resume_break_address = inf_status->step_resume_break_address; stop_after_trap = inf_status->stop_after_trap; stop_soon_quietly = inf_status->stop_soon_quietly; bpstat_clear (&stop_bpstat); stop_bpstat = inf_status->stop_bpstat; breakpoint_proceeded = inf_status->breakpoint_proceeded; proceed_to_finish = inf_status->proceed_to_finish; bcopy (inf_status->stop_registers, stop_registers, REGISTER_BYTES); /* The inferior can be gone if the user types "print exit(0)" (and perhaps other times). */ if (target_has_stack && inf_status->restore_stack_info) { fid = find_relative_frame (get_current_frame (), &level); /* If inf_status->selected_frame_address is NULL, there was no previously selected frame. */ if (fid == 0 || FRAME_FP (fid) != inf_status->selected_frame_address || level != 0) { #if 1 /* I'm not sure this error message is a good idea. I have only seen it occur after "Can't continue previously requested operation" (we get called from do_cleanups), in which case it just adds insult to injury (one confusing error message after another. Besides which, does the user really care if we can't restore the previously selected frame? */ fprintf (stderr, "Unable to restore previously selected frame.\n"); #endif select_frame (get_current_frame (), 0); return; } select_frame (fid, inf_status->selected_level); } } void _initialize_infrun () { register int i; add_info ("signals", signals_info, "What debugger does when program gets various signals.\n\ Specify a signal number as argument to print info on that signal only."); add_com ("handle", class_run, handle_command, "Specify how to handle a signal.\n\ Args are signal number followed by flags.\n\ Flags allowed are \"stop\", \"print\", \"pass\",\n\ \"nostop\", \"noprint\" or \"nopass\".\n\ Print means print a message if this signal happens.\n\ Stop means reenter debugger if this signal happens (implies print).\n\ Pass means let program see this signal; otherwise program doesn't know.\n\ Pass and Stop may be combined."); for (i = 0; i < NSIG; i++) { signal_stop[i] = 1; signal_print[i] = 1; signal_program[i] = 1; } /* Signals caused by debugger's own actions should not be given to the program afterwards. */ signal_program[SIGTRAP] = 0; signal_program[SIGINT] = 0; /* Signals that are not errors should not normally enter the debugger. */ #ifdef SIGALRM signal_stop[SIGALRM] = 0; signal_print[SIGALRM] = 0; #endif /* SIGALRM */ #ifdef SIGVTALRM signal_stop[SIGVTALRM] = 0; signal_print[SIGVTALRM] = 0; #endif /* SIGVTALRM */ #ifdef SIGPROF signal_stop[SIGPROF] = 0; signal_print[SIGPROF] = 0; #endif /* SIGPROF */ #ifdef SIGCHLD signal_stop[SIGCHLD] = 0; signal_print[SIGCHLD] = 0; #endif /* SIGCHLD */ #ifdef SIGCLD signal_stop[SIGCLD] = 0; signal_print[SIGCLD] = 0; #endif /* SIGCLD */ #ifdef SIGIO signal_stop[SIGIO] = 0; signal_print[SIGIO] = 0; #endif /* SIGIO */ #ifdef SIGURG signal_stop[SIGURG] = 0; signal_print[SIGURG] = 0; #endif /* SIGURG */ } @