diff options
Diffstat (limited to 'bin/sh/trap.c')
| -rw-r--r-- | bin/sh/trap.c | 837 |
1 files changed, 0 insertions, 837 deletions
diff --git a/bin/sh/trap.c b/bin/sh/trap.c deleted file mode 100644 index cb641fd..0000000 --- a/bin/sh/trap.c +++ /dev/null @@ -1,837 +0,0 @@ -/* $NetBSD: trap.c,v 1.51 2019/01/18 06:28:09 kre Exp $ */ - -/*- - * 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. - */ - -#include <sys/cdefs.h> -#ifndef lint -#if 0 -static char sccsid[] = "@(#)trap.c 8.5 (Berkeley) 6/5/95"; -#else -__RCSID("$NetBSD: trap.c,v 1.51 2019/01/18 06:28:09 kre Exp $"); -#endif -#endif /* not lint */ - -#include <signal.h> -#include <unistd.h> -#include <stdlib.h> -#include <stdio.h> -#include <errno.h> -#include <termios.h> - -#undef CEOF /* from <termios.h> but concflicts with sh use */ - -#include <sys/ioctl.h> -#include <sys/resource.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 "builtins.h" -#include "syntax.h" -#include "output.h" -#include "memalloc.h" -#include "error.h" -#include "trap.h" -#include "mystring.h" -#include "var.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 permenantly */ -#define S_RESET 5 /* temporary - to reset a hard ignored sig */ - - -MKINIT char sigmode[NSIG]; /* current value of signal */ -static volatile sig_atomic_t gotsig[NSIG];/* indicates specified signal received */ -volatile sig_atomic_t pendingsigs; /* indicates some signal received */ - -int traps_invalid; /* in a subshell, but trap[] not yet cleared */ -static char * volatile trap[NSIG]; /* trap handler commands */ -static int in_dotrap; -static int last_trapsig; - -static int exiting; /* exitshell() has been done */ -static int exiting_status; /* the status to use for exit() */ - -static int getsigaction(int, sig_t *); -STATIC const char *trap_signame(int); -void printsignals(struct output *, int); - -/* - * return the signal number described by `p' (as a number or a name) - * or -1 if it isn't one - */ - -static int -signame_to_signum(const char *p) -{ - int i; - - if (is_number(p)) - return number(p); - - if (strcasecmp(p, "exit") == 0 ) - return 0; - - i = signalnumber(p); - if (i == 0) - i = -1; - return i; -} - -/* - * return the name of a signal used by the "trap" command - */ -STATIC const char * -trap_signame(int signo) -{ - static char nbuf[12]; - const char *p; - - if (signo == 0) - return "EXIT"; - p = signalname(signo); - if (p != NULL) - return p; - (void)snprintf(nbuf, sizeof nbuf, "%d", signo); - return nbuf; -} - -#ifdef SMALL -/* - * Print a list of valid signal names - */ -void -printsignals(struct output *out, int len) -{ - int n; - - if (len != 0) - outc(' ', out); - for (n = 1; n < NSIG; n++) { - outfmt(out, "%s", trap_signame(n)); - if ((n == NSIG/2) || n == (NSIG - 1)) - outstr("\n", out); - else - outc(' ', out); - } -} -#else /* !SMALL */ -/* - * Print the names of all the signals (neatly) to fp - * "len" gives the number of chars already printed to - * the current output line (in kill.c, always 0) - */ -void -printsignals(struct output *out, int len) -{ - int sig; - int nl, pad; - const char *name; - int termwidth = 80; - - if ((name = bltinlookup("COLUMNS", 1)) != NULL) - termwidth = (int)strtol(name, NULL, 10); - else if (isatty(1)) { - struct winsize win; - - if (ioctl(1, TIOCGWINSZ, &win) == 0 && win.ws_col > 0) - termwidth = win.ws_col; - } - - if (posix) - pad = 1; - else - pad = (len | 7) + 1 - len; - - for (sig = 0; (sig = signalnext(sig)) != 0; ) { - name = signalname(sig); - if (name == NULL) - continue; - - nl = strlen(name); - - if (len > 0 && nl + len + pad >= termwidth) { - outc('\n', out); - len = 0; - pad = 0; - } else if (pad > 0 && len != 0) - outfmt(out, "%*s", pad, ""); - else - pad = 0; - - len += nl + pad; - if (!posix) - pad = (nl | 7) + 1 - nl; - else - pad = 1; - - outstr(name, out); - } - if (len != 0) - outc('\n', out); -} -#endif /* SMALL */ - -/* - * The trap builtin. - */ - -int -trapcmd(int argc, char **argv) -{ - char *action; - char **ap; - int signo; - int errs = 0; - int printonly = 0; - - ap = argv + 1; - - CTRACE(DBG_TRAP, ("trapcmd: ")); - if (argc == 2 && strcmp(*ap, "-l") == 0) { - CTRACE(DBG_TRAP, ("-l\n")); - out1str("EXIT"); - printsignals(out1, 4); - return 0; - } - if (argc == 2 && strcmp(*ap, "-") == 0) { - CTRACE(DBG_TRAP, ("-\n")); - for (signo = 0; signo < NSIG; signo++) { - if (trap[signo] == NULL) - continue; - INTOFF; - ckfree(trap[signo]); - trap[signo] = NULL; - if (signo != 0) - setsignal(signo, 0); - INTON; - } - traps_invalid = 0; - return 0; - } - if (argc >= 2 && strcmp(*ap, "-p") == 0) { - CTRACE(DBG_TRAP, ("-p ")); - printonly = 1; - ap++; - argc--; - } - - if (argc > 1 && strcmp(*ap, "--") == 0) { - argc--; - ap++; - } - - if (argc <= 1) { - int count; - - CTRACE(DBG_TRAP, ("*all*\n")); - if (printonly) { - for (count = 0, signo = 0 ; signo < NSIG ; signo++) - if (trap[signo] == NULL) { - if (count == 0) - out1str("trap -- -"); - out1fmt(" %s", trap_signame(signo)); - /* oh! unlucky 13 */ - if (++count >= 13) { - out1str("\n"); - count = 0; - } - } - if (count) - out1str("\n"); - } - - for (count = 0, signo = 0 ; signo < NSIG ; signo++) - if (trap[signo] != NULL && trap[signo][0] == '\0') { - if (count == 0) - out1str("trap -- ''"); - out1fmt(" %s", trap_signame(signo)); - /* - * the prefix is 10 bytes, with 4 byte - * signal names (common) we have room in - * the 70 bytes left on a normal line for - * 70/(4+1) signals, that's 14, but to - * allow for the occasional longer sig name - * we output one less... - */ - if (++count >= 13) { - out1str("\n"); - count = 0; - } - } - if (count) - out1str("\n"); - - for (signo = 0 ; signo < NSIG ; signo++) - if (trap[signo] != NULL && trap[signo][0] != '\0') { - out1str("trap -- "); - print_quoted(trap[signo]); - out1fmt(" %s\n", trap_signame(signo)); - } - - return 0; - } - CTRACE(DBG_TRAP, ("\n")); - - action = NULL; - - if (!printonly && traps_invalid) - free_traps(); - - if (!printonly && !is_number(*ap)) { - if ((*ap)[0] == '-' && (*ap)[1] == '\0') - ap++; /* reset to default */ - else - action = *ap++; /* can be '' for "ignore" */ - argc--; - } - - if (argc < 2) { /* there must be at least 1 condition */ - out2str("Usage: trap [-l]\n" - " trap -p [condition ...]\n" - " trap action condition ...\n" - " trap N condition ...\n"); - return 2; - } - - - while (*ap) { - signo = signame_to_signum(*ap); - - if (signo < 0 || signo >= NSIG) { - /* This is not a fatal error, so sayeth posix */ - outfmt(out2, "trap: '%s' bad condition\n", *ap); - errs = 1; - ap++; - continue; - } - ap++; - - if (printonly) { - out1str("trap -- "); - if (trap[signo] == NULL) - out1str("-"); - else - print_quoted(trap[signo]); - out1fmt(" %s\n", trap_signame(signo)); - continue; - } - - INTOFF; - if (action) - action = savestr(action); - - VTRACE(DBG_TRAP, ("trap for %d from %s%s%s to %s%s%s\n", signo, - trap[signo] ? "'" : "", trap[signo] ? trap[signo] : "-", - trap[signo] ? "'" : "", action ? "'" : "", - action ? action : "-", action ? "'" : "")); - - if (trap[signo]) - ckfree(trap[signo]); - - trap[signo] = action; - - if (signo != 0) - setsignal(signo, 0); - INTON; - } - return errs; -} - - - -/* - * Clear traps on a fork or vfork. - * Takes one arg vfork, to tell it to not be destructive of - * the parents variables. - */ -void -clear_traps(int vforked) -{ - char * volatile *tp; - - VTRACE(DBG_TRAP, ("clear_traps(%d)\n", vforked)); - if (!vforked) - traps_invalid = 1; - - for (tp = &trap[1] ; tp < &trap[NSIG] ; tp++) { - if (*tp && **tp) { /* trap not NULL or SIG_IGN */ - INTOFF; - setsignal(tp - trap, vforked == 1); - INTON; - } - } - if (vforked == 2) - free_traps(); -} - -void -free_traps(void) -{ - char * volatile *tp; - - VTRACE(DBG_TRAP, ("free_traps%s\n", traps_invalid ? "(invalid)" : "")); - INTOFF; - for (tp = trap ; tp < &trap[NSIG] ; tp++) - if (*tp && **tp) { - ckfree(*tp); - *tp = NULL; - } - traps_invalid = 0; - INTON; -} - -/* - * See if there are any defined traps - */ -int -have_traps(void) -{ - char * volatile *tp; - - if (traps_invalid) - return 0; - - for (tp = trap ; tp < &trap[NSIG] ; 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 vforked) -{ - int action; - sig_t sigact = SIG_DFL, sig; - char *t, tsig; - - if (traps_invalid || (t = trap[signo]) == NULL) - action = S_DFL; - else if (*t != '\0') - action = S_CATCH; - else - action = S_IGN; - - VTRACE(DBG_TRAP, ("setsignal(%d%s) -> %d", signo, - vforked ? ", VF" : "", action)); - if (rootshell && !vforked && action == S_DFL) { - switch (signo) { - case SIGINT: - if (iflag || minusc || sflag == 0) - action = S_CATCH; - break; - case SIGQUIT: -#ifdef DEBUG - if (debug) - break; -#endif - /* FALLTHROUGH */ - case SIGTERM: - if (rootshell && iflag) - action = S_IGN; - break; -#if JOBS - case SIGTSTP: - case SIGTTOU: - if (rootshell && mflag) - action = S_IGN; - break; -#endif - } - } - - /* - * Never let users futz with SIGCHLD - * instead we will give them pseudo SIGCHLD's - * when background jobs complete. - */ - if (signo == SIGCHLD) - action = S_DFL; - - VTRACE(DBG_TRAP, (" -> %d", action)); - - t = &sigmode[signo]; - tsig = *t; - if (tsig == 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. - */ - VTRACE(DBG_TRAP, (" getsigaction (%d)\n", errno)); - return; - } - VTRACE(DBG_TRAP, (" [%s]%s%s", sigact==SIG_IGN ? "IGN" : - sigact==SIG_DFL ? "DFL" : "caught", - iflag ? "i" : "", mflag ? "m" : "")); - - if (sigact == SIG_IGN) { - /* - * POSIX 3.14.13 states that non-interactive shells - * should ignore trap commands for signals that were - * ignored upon entry, and leaves the behavior - * unspecified for interactive shells. On interactive - * shells, or if job control is on, and we have a job - * control related signal, we allow the trap to work. - * - * This change allows us to be POSIX compliant, and - * at the same time override the default behavior if - * we need to by setting the interactive flag. - */ - if ((mflag && (signo == SIGTSTP || - signo == SIGTTIN || signo == SIGTTOU)) || iflag) { - tsig = S_IGN; - } else - tsig = S_HARD_IGN; - } else { - tsig = S_RESET; /* force to be set */ - } - } - VTRACE(DBG_TRAP, (" tsig=%d\n", tsig)); - - if (tsig == S_HARD_IGN || tsig == action) - return; - - switch (action) { - case S_DFL: sigact = SIG_DFL; break; - case S_CATCH: sigact = onsig; break; - case S_IGN: sigact = SIG_IGN; break; - } - - sig = signal(signo, sigact); - - if (sig != SIG_ERR) { - sigset_t ss; - - if (!vforked) - *t = action; - - if (action == S_CATCH) - (void)siginterrupt(signo, 1); - /* - * If our parent accidentally blocked signals for - * us make sure we unblock them - */ - (void)sigemptyset(&ss); - (void)sigaddset(&ss, signo); - (void)sigprocmask(SIG_UNBLOCK, &ss, NULL); - } - return; -} - -/* - * 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, int vforked) -{ - if (sigmode[signo] == 0) - setsignal(signo, vforked); - - VTRACE(DBG_TRAP, ("ignoresig(%d%s)\n", signo, vforked ? ", VF" : "")); - if (sigmode[signo] != S_IGN && sigmode[signo] != S_HARD_IGN) { - signal(signo, SIG_IGN); - if (!vforked) - sigmode[signo] = S_IGN; - } -} - -char * -child_trap(void) -{ - char * p; - - p = trap[SIGCHLD]; - - if (traps_invalid || (p != NULL && *p == '\0')) - p = NULL; - - return p; -} - - -#ifdef mkinit -INCLUDE <signal.h> -INCLUDE "trap.h" -INCLUDE "shell.h" -INCLUDE "show.h" - -SHELLPROC { - char *sm; - - INTOFF; - clear_traps(2); - for (sm = sigmode ; sm < sigmode + NSIG ; sm++) { - if (*sm == S_IGN) { - *sm = S_HARD_IGN; - VTRACE(DBG_TRAP, ("SHELLPROC: %d -> hard_ign\n", - (sm - sigmode))); - } - } - INTON; -} -#endif - - - -/* - * Signal handler. - */ - -void -onsig(int signo) -{ - CTRACE(DBG_SIG, ("Signal %d, had: pending %d, gotsig[%d]=%d\n", - signo, pendingsigs, signo, gotsig[signo])); - - /* This should not be needed. - signal(signo, onsig); - */ - - if (signo == SIGINT && (traps_invalid || trap[SIGINT] == NULL)) { - onint(); - return; - } - - /* - * if the signal will do nothing, no point reporting it - */ - if (!traps_invalid && trap[signo] != NULL && trap[signo][0] != '\0' && - signo != SIGCHLD) { - gotsig[signo] = 1; - pendingsigs++; - } -} - - - -/* - * Called to execute a trap. Perhaps we should avoid entering new trap - * handlers while we are executing a trap handler. - */ - -void -dotrap(void) -{ - int i; - char *tr; - int savestatus; - struct skipsave saveskip; - - in_dotrap++; - - CTRACE(DBG_TRAP, ("dotrap[%d]: %d pending, traps %sinvalid\n", - in_dotrap, pendingsigs, traps_invalid ? "" : "not ")); - for (;;) { - pendingsigs = 0; - for (i = 1 ; ; i++) { - if (i >= NSIG) - return; - if (gotsig[i]) - break; - } - gotsig[i] = 0; - - if (traps_invalid) - continue; - - tr = trap[i]; - - CTRACE(DBG_TRAP|DBG_SIG, ("dotrap %d: %s%s%s\n", i, - tr ? "\"" : "", tr ? tr : "NULL", tr ? "\"" : "")); - - if (tr != NULL) { - last_trapsig = i; - save_skipstate(&saveskip); - savestatus = exitstatus; - - tr = savestr(tr); /* trap code may free trap[i] */ - evalstring(tr, 0); - ckfree(tr); - - if (current_skipstate() == SKIPNONE || - saveskip.state != SKIPNONE) { - restore_skipstate(&saveskip); - exitstatus = savestatus; - } - } - } - - in_dotrap--; -} - -int -lastsig(void) -{ - int i; - - for (i = NSIG; --i > 0; ) - if (gotsig[i]) - return i; - return SIGINT; /* XXX */ -} - -/* - * Controls whether the shell is interactive or not. - */ - - -void -setinteractive(int on) -{ - static int is_interactive; - - if (on == is_interactive) - return; - setsignal(SIGINT, 0); - setsignal(SIGQUIT, 0); - setsignal(SIGTERM, 0); - is_interactive = on; -} - - - -/* - * Called to exit the shell. - */ -void -exitshell(int status) -{ - CTRACE(DBG_ERRS|DBG_PROCS|DBG_CMDS|DBG_TRAP, - ("pid %d: exitshell(%d)\n", getpid(), status)); - - exiting = 1; - exiting_status = status; - exitshell_savedstatus(); -} - -void -exitshell_savedstatus(void) -{ - struct jmploc loc; - char *p; - volatile int sig = 0; - int s; - sigset_t sigs; - - CTRACE(DBG_ERRS|DBG_PROCS|DBG_CMDS|DBG_TRAP, - ("pid %d: exitshell_savedstatus()%s $?=%d xs=%d dt=%d ts=%d\n", - getpid(), exiting ? " exiting" : "", exitstatus, - exiting_status, in_dotrap, last_trapsig)); - - if (!exiting) { - if (in_dotrap && last_trapsig) { - sig = last_trapsig; - exiting_status = sig + 128; - } else - exiting_status = exitstatus; - } - exitstatus = exiting_status; - - if (!setjmp(loc.loc)) { - handler = &loc; - - if (!traps_invalid && (p = trap[0]) != NULL && *p != '\0') { - reset_eval(); - trap[0] = NULL; - VTRACE(DBG_TRAP, ("exit trap: \"%s\"\n", p)); - evalstring(p, 0); - } - } - - INTOFF; /* we're done, no more interrupts. */ - - if (!setjmp(loc.loc)) { - handler = &loc; /* probably unnecessary */ - flushall(); -#if JOBS - setjobctl(0); -#endif - } - - if ((s = sig) != 0 && s != SIGSTOP && s != SIGTSTP && s != SIGTTIN && - s != SIGTTOU) { - struct rlimit nocore; - - /* - * if the signal is of the core dump variety, don't... - */ - nocore.rlim_cur = nocore.rlim_max = 0; - (void) setrlimit(RLIMIT_CORE, &nocore); - - signal(s, SIG_DFL); - sigemptyset(&sigs); - sigaddset(&sigs, s); - sigprocmask(SIG_UNBLOCK, &sigs, NULL); - - kill(getpid(), s); - } - _exit(exiting_status); - /* NOTREACHED */ -} |