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Diffstat (limited to 'bin/1sh/trap.c')
| -rw-r--r-- | bin/1sh/trap.c | 553 |
1 files changed, 0 insertions, 553 deletions
diff --git a/bin/1sh/trap.c b/bin/1sh/trap.c deleted file mode 100644 index fed13fcf..00000000 --- a/bin/1sh/trap.c +++ /dev/null @@ -1,553 +0,0 @@ -/*- - * SPDX-License-Identifier: BSD-3-Clause - * - * Copyright (c) 1991, 1993 - * The Regents of the University of California. All rights reserved. - * - * This code is derived from software contributed to Berkeley by - * Kenneth Almquist. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#ifndef lint -#if 0 -static char sccsid[] = "@(#)trap.c 8.5 (Berkeley) 6/5/95"; -#endif -#endif /* not lint */ -#include <sys/cdefs.h> -/* $FreeBSD: releng/12.1/bin/sh/trap.c 326025 2017-11-20 19:49:47Z pfg $ */ - -#include <signal.h> -#include <unistd.h> -#include <stdlib.h> - -#include "shell.h" -#include "main.h" -#include "nodes.h" /* for other headers */ -#include "eval.h" -#include "jobs.h" -#include "show.h" -#include "options.h" -#include "syntax.h" -#include "output.h" -#include "memalloc.h" -#include "error.h" -#include "trap.h" -#include "mystring.h" -#include "builtins.h" -#include "myhistedit.h" - - -/* - * Sigmode records the current value of the signal handlers for the various - * modes. A value of zero means that the current handler is not known. - * S_HARD_IGN indicates that the signal was ignored on entry to the shell, - */ - -#define S_DFL 1 /* default signal handling (SIG_DFL) */ -#define S_CATCH 2 /* signal is caught */ -#define S_IGN 3 /* signal is ignored (SIG_IGN) */ -#define S_HARD_IGN 4 /* signal is ignored permanently */ -#define S_RESET 5 /* temporary - to reset a hard ignored sig */ - - -static char sigmode[NSIG]; /* current value of signal */ -volatile sig_atomic_t pendingsig; /* indicates some signal received */ -volatile sig_atomic_t pendingsig_waitcmd; /* indicates wait builtin should be interrupted */ -static int in_dotrap; /* do we execute in a trap handler? */ -static char *volatile trap[NSIG]; /* trap handler commands */ -static volatile sig_atomic_t gotsig[NSIG]; - /* indicates specified signal received */ -static int ignore_sigchld; /* Used while handling SIGCHLD traps. */ -static int last_trapsig; - -static int exiting; /* exitshell() has been called */ -static int exiting_exitstatus; /* value passed to exitshell() */ - -static int getsigaction(int, sig_t *); - - -/* - * Map a string to a signal number. - * - * Note: the signal number may exceed NSIG. - */ -static int -sigstring_to_signum(char *sig) -{ - - if (is_number(sig)) { - int signo; - - signo = atoi(sig); - return ((signo >= 0 && signo < NSIG) ? signo : (-1)); - } else if (strcasecmp(sig, "EXIT") == 0) { - return (0); - } else { - int n; - - if (strncasecmp(sig, "SIG", 3) == 0) - sig += 3; - for (n = 1; n < NSIG; n++) - if (sys_signame[n] && - strcasecmp(sys_signame[n], sig) == 0) - return (n); - } - return (-1); -} - - -/* - * Print a list of valid signal names. - */ -static void -printsignals(void) -{ - int n, outlen; - - outlen = 0; - for (n = 1; n < NSIG; n++) { - if (sys_signame[n]) { - out1fmt("%s", sys_signame[n]); - outlen += strlen(sys_signame[n]); - } else { - out1fmt("%d", n); - outlen += 3; /* good enough */ - } - ++outlen; - if (outlen > 71 || n == NSIG - 1) { - out1str("\n"); - outlen = 0; - } else { - out1c(' '); - } - } -} - - -/* - * The trap builtin. - */ -int -trapcmd(int argc __unused, char **argv) -{ - char *action; - int signo; - int errors = 0; - int i; - - while ((i = nextopt("l")) != '\0') { - switch (i) { - case 'l': - printsignals(); - return (0); - } - } - argv = argptr; - - if (*argv == NULL) { - for (signo = 0 ; signo < NSIG ; signo++) { - if (signo < NSIG && trap[signo] != NULL) { - out1str("trap -- "); - out1qstr(trap[signo]); - if (signo == 0) { - out1str(" EXIT\n"); - } else if (sys_signame[signo]) { - out1fmt(" %s\n", sys_signame[signo]); - } else { - out1fmt(" %d\n", signo); - } - } - } - return 0; - } - action = NULL; - if (*argv && !is_number(*argv)) { - if (strcmp(*argv, "-") == 0) - argv++; - else { - action = *argv; - argv++; - } - } - for (; *argv; argv++) { - if ((signo = sigstring_to_signum(*argv)) == -1) { - warning("bad signal %s", *argv); - errors = 1; - continue; - } - INTOFF; - if (action) - action = savestr(action); - if (trap[signo]) - ckfree(trap[signo]); - trap[signo] = action; - if (signo != 0) - setsignal(signo); - INTON; - } - return errors; -} - - -/* - * Clear traps on a fork. - */ -void -clear_traps(void) -{ - char *volatile *tp; - - for (tp = trap ; tp <= &trap[NSIG - 1] ; tp++) { - if (*tp && **tp) { /* trap not NULL or SIG_IGN */ - INTOFF; - ckfree(*tp); - *tp = NULL; - if (tp != &trap[0]) - setsignal(tp - trap); - INTON; - } - } -} - - -/* - * Check if we have any traps enabled. - */ -int -have_traps(void) -{ - char *volatile *tp; - - for (tp = trap ; tp <= &trap[NSIG - 1] ; tp++) { - if (*tp && **tp) /* trap not NULL or SIG_IGN */ - return 1; - } - return 0; -} - -/* - * Set the signal handler for the specified signal. The routine figures - * out what it should be set to. - */ -void -setsignal(int signo) -{ - int action; - sig_t sigact = SIG_DFL; - struct sigaction sa; - char *t; - - if ((t = trap[signo]) == NULL) - action = S_DFL; - else if (*t != '\0') - action = S_CATCH; - else - action = S_IGN; - if (action == S_DFL) { - switch (signo) { - case SIGINT: - action = S_CATCH; - break; - case SIGQUIT: -#ifdef DEBUG - { - extern int debug; - - if (debug) - break; - } -#endif - action = S_CATCH; - break; - case SIGTERM: - if (rootshell && iflag) - action = S_IGN; - break; -#if JOBS - case SIGTSTP: - case SIGTTOU: - if (rootshell && mflag) - action = S_IGN; - break; -#endif - } - } - - t = &sigmode[signo]; - if (*t == 0) { - /* - * current setting unknown - */ - if (!getsigaction(signo, &sigact)) { - /* - * Pretend it worked; maybe we should give a warning - * here, but other shells don't. We don't alter - * sigmode, so that we retry every time. - */ - return; - } - if (sigact == SIG_IGN) { - if (mflag && (signo == SIGTSTP || - signo == SIGTTIN || signo == SIGTTOU)) { - *t = S_IGN; /* don't hard ignore these */ - } else - *t = S_HARD_IGN; - } else { - *t = S_RESET; /* force to be set */ - } - } - if (*t == S_HARD_IGN || *t == action) - return; - switch (action) { - case S_DFL: sigact = SIG_DFL; break; - case S_CATCH: sigact = onsig; break; - case S_IGN: sigact = SIG_IGN; break; - } - *t = action; - sa.sa_handler = sigact; - sa.sa_flags = 0; - sigemptyset(&sa.sa_mask); - sigaction(signo, &sa, NULL); -} - - -/* - * Return the current setting for sig w/o changing it. - */ -static int -getsigaction(int signo, sig_t *sigact) -{ - struct sigaction sa; - - if (sigaction(signo, (struct sigaction *)0, &sa) == -1) - return 0; - *sigact = (sig_t) sa.sa_handler; - return 1; -} - - -/* - * Ignore a signal. - */ -void -ignoresig(int signo) -{ - - if (sigmode[signo] == 0) - setsignal(signo); - if (sigmode[signo] != S_IGN && sigmode[signo] != S_HARD_IGN) { - signal(signo, SIG_IGN); - sigmode[signo] = S_IGN; - } -} - - -int -issigchldtrapped(void) -{ - - return (trap[SIGCHLD] != NULL && *trap[SIGCHLD] != '\0'); -} - - -/* - * Signal handler. - */ -void -onsig(int signo) -{ - - if (signo == SIGINT && trap[SIGINT] == NULL) { - /* - * The !in_dotrap here is safe. The only way we can arrive - * here with in_dotrap set is that a trap handler set SIGINT to - * SIG_DFL and killed itself. - */ - if (suppressint && !in_dotrap) - SET_PENDING_INT; - else - onint(); - return; - } - - /* If we are currently in a wait builtin, prepare to break it */ - if (signo == SIGINT || signo == SIGQUIT) - pendingsig_waitcmd = signo; - - if (trap[signo] != NULL && trap[signo][0] != '\0' && - (signo != SIGCHLD || !ignore_sigchld)) { - gotsig[signo] = 1; - pendingsig = signo; - pendingsig_waitcmd = signo; - } -} - - -/* - * Called to execute a trap. Perhaps we should avoid entering new trap - * handlers while we are executing a trap handler. - */ -void -dotrap(void) -{ - struct stackmark smark; - int i; - int savestatus, prev_evalskip, prev_skipcount; - - in_dotrap++; - for (;;) { - pendingsig = 0; - pendingsig_waitcmd = 0; - for (i = 1; i < NSIG; i++) { - if (gotsig[i]) { - gotsig[i] = 0; - if (trap[i]) { - /* - * Ignore SIGCHLD to avoid infinite - * recursion if the trap action does - * a fork. - */ - if (i == SIGCHLD) - ignore_sigchld++; - - /* - * Backup current evalskip - * state and reset it before - * executing a trap, so that the - * trap is not disturbed by an - * ongoing break/continue/return - * statement. - */ - prev_evalskip = evalskip; - prev_skipcount = skipcount; - evalskip = 0; - - last_trapsig = i; - savestatus = exitstatus; - setstackmark(&smark); - evalstring(stsavestr(trap[i]), 0); - popstackmark(&smark); - - /* - * If such a command was not - * already in progress, allow a - * break/continue/return in the - * trap action to have an effect - * outside of it. - */ - if (evalskip == 0 || - prev_evalskip != 0) { - evalskip = prev_evalskip; - skipcount = prev_skipcount; - exitstatus = savestatus; - } - - if (i == SIGCHLD) - ignore_sigchld--; - } - break; - } - } - if (i >= NSIG) - break; - } - in_dotrap--; -} - - -/* - * Controls whether the shell is interactive or not based on iflag. - */ -void -setinteractive(void) -{ - setsignal(SIGINT); - setsignal(SIGQUIT); - setsignal(SIGTERM); -} - - -/* - * Called to exit the shell. - */ -void -exitshell(int status) -{ - TRACE(("exitshell(%d) pid=%d\n", status, getpid())); - exiting = 1; - exiting_exitstatus = status; - exitshell_savedstatus(); -} - -void -exitshell_savedstatus(void) -{ - struct jmploc loc1, loc2; - char *p; - int sig = 0; - sigset_t sigs; - - if (!exiting) { - if (in_dotrap && last_trapsig) { - sig = last_trapsig; - exiting_exitstatus = sig + 128; - } else - exiting_exitstatus = oexitstatus; - } - exitstatus = oexitstatus = exiting_exitstatus; - if (!setjmp(loc1.loc)) { - handler = &loc1; - if ((p = trap[0]) != NULL && *p != '\0') { - /* - * Reset evalskip, or the trap on EXIT could be - * interrupted if the last command was a "return". - */ - evalskip = 0; - trap[0] = NULL; - FORCEINTON; - evalstring(p, 0); - } - } - if (!setjmp(loc2.loc)) { - handler = &loc2; /* probably unnecessary */ - FORCEINTON; - flushall(); -#if JOBS - setjobctl(0); -#endif - } - if (sig != 0 && sig != SIGSTOP && sig != SIGTSTP && sig != SIGTTIN && - sig != SIGTTOU) { - signal(sig, SIG_DFL); - sigemptyset(&sigs); - sigaddset(&sigs, sig); - sigprocmask(SIG_UNBLOCK, &sigs, NULL); - kill(getpid(), sig); - /* If the default action is to ignore, fall back to _exit(). */ - } - _exit(exiting_exitstatus); -} |