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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 17:06:04 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 17:06:04 +0000
commit2f0649f6fe411d7e07c8d56cf8ea56db53536da8 (patch)
tree778611fb52176dce1ad06c68e87b2cb348ca0f7b /usr/dash/trap.c
parentInitial commit. (diff)
downloadklibc-2f0649f6fe411d7e07c8d56cf8ea56db53536da8.tar.xz
klibc-2f0649f6fe411d7e07c8d56cf8ea56db53536da8.zip
Adding upstream version 2.0.13.upstream/2.0.13upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'usr/dash/trap.c')
-rw-r--r--usr/dash/trap.c467
1 files changed, 467 insertions, 0 deletions
diff --git a/usr/dash/trap.c b/usr/dash/trap.c
new file mode 100644
index 0000000..1e2a867
--- /dev/null
+++ b/usr/dash/trap.c
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+/*-
+ * Copyright (c) 1991, 1993
+ * The Regents of the University of California. All rights reserved.
+ * Copyright (c) 1997-2005
+ * Herbert Xu <herbert@gondor.apana.org.au>. 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 <signal.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.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"
+
+#ifdef HETIO
+#include "hetio.h"
+#endif
+
+/*
+ * 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 */
+
+
+/* trap handler commands */
+static char *trap[NSIG];
+/* number of non-null traps */
+int trapcnt;
+/* current value of signal */
+char sigmode[NSIG - 1];
+/* indicates specified signal received */
+static char gotsig[NSIG - 1];
+/* last pending signal */
+volatile sig_atomic_t pendingsigs;
+/* received SIGCHLD */
+int gotsigchld;
+
+#ifdef mkinit
+INCLUDE "trap.h"
+INIT {
+ sigmode[SIGCHLD - 1] = S_DFL;
+ setsignal(SIGCHLD);
+}
+#endif
+
+/*
+ * The trap builtin.
+ */
+
+int
+trapcmd(int argc, char **argv)
+{
+ char *action;
+ char **ap;
+ int signo;
+
+ nextopt(nullstr);
+ ap = argptr;
+ if (!*ap) {
+ for (signo = 0 ; signo < NSIG ; signo++) {
+ if (trap[signo] != NULL) {
+ out1fmt(
+ "trap -- %s %s\n",
+ single_quote(trap[signo]),
+ signal_name(signo)
+ );
+ }
+ }
+ return 0;
+ }
+ if (!ap[1])
+ action = NULL;
+ else
+ action = *ap++;
+ while (*ap) {
+ if ((signo = decode_signal(*ap, 0)) < 0) {
+ outfmt(out2, "trap: %s: bad trap\n", *ap);
+ return 1;
+ }
+ INTOFF;
+ if (action) {
+ if (action[0] == '-' && action[1] == '\0')
+ action = NULL;
+ else {
+ if (*action)
+ trapcnt++;
+ action = savestr(action);
+ }
+ }
+ if (trap[signo]) {
+ if (*trap[signo])
+ trapcnt--;
+ ckfree(trap[signo]);
+ }
+ trap[signo] = action;
+ if (signo != 0)
+ setsignal(signo);
+ INTON;
+ ap++;
+ }
+ return 0;
+}
+
+
+
+/*
+ * Clear traps on a fork.
+ */
+
+void
+clear_traps(void)
+{
+ char **tp;
+
+ INTOFF;
+ for (tp = trap ; tp < &trap[NSIG] ; tp++) {
+ if (*tp && **tp) { /* trap not NULL or SIG_IGN */
+ ckfree(*tp);
+ *tp = NULL;
+ if (tp != &trap[0])
+ setsignal(tp - trap);
+ }
+ }
+ trapcnt = 0;
+ INTON;
+}
+
+
+
+/*
+ * Set the signal handler for the specified signal. The routine figures
+ * out what it should be set to.
+ */
+
+void
+setsignal(int signo)
+{
+ int action;
+ char *t, tsig;
+ struct sigaction act;
+
+ if ((t = trap[signo]) == NULL)
+ action = S_DFL;
+ else if (*t != '\0')
+ action = S_CATCH;
+ else
+ action = S_IGN;
+ if (rootshell && 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 (iflag)
+ action = S_IGN;
+ break;
+#if JOBS
+ case SIGTSTP:
+ case SIGTTOU:
+ if (mflag)
+ action = S_IGN;
+ break;
+#endif
+ }
+ }
+
+ if (signo == SIGCHLD)
+ action = S_CATCH;
+
+ t = &sigmode[signo - 1];
+ tsig = *t;
+ if (tsig == 0) {
+ /*
+ * current setting unknown
+ */
+ if (sigaction(signo, 0, &act) == -1) {
+ /*
+ * 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 (act.sa_handler == SIG_IGN) {
+ if (mflag && (signo == SIGTSTP ||
+ signo == SIGTTIN || signo == SIGTTOU)) {
+ tsig = S_IGN; /* don't hard ignore these */
+ } else
+ tsig = S_HARD_IGN;
+ } else {
+ tsig = S_RESET; /* force to be set */
+ }
+ }
+ if (tsig == S_HARD_IGN || tsig == action)
+ return;
+ switch (action) {
+ case S_CATCH:
+ act.sa_handler = onsig;
+ break;
+ case S_IGN:
+ act.sa_handler = SIG_IGN;
+ break;
+ default:
+ act.sa_handler = SIG_DFL;
+ }
+ *t = action;
+ act.sa_flags = 0;
+ sigfillset(&act.sa_mask);
+ sigaction(signo, &act, 0);
+}
+
+/*
+ * Ignore a signal.
+ */
+
+void
+ignoresig(int signo)
+{
+ if (sigmode[signo - 1] != S_IGN && sigmode[signo - 1] != S_HARD_IGN) {
+ signal(signo, SIG_IGN);
+ }
+ sigmode[signo - 1] = S_HARD_IGN;
+}
+
+
+
+/*
+ * Signal handler.
+ */
+
+void
+onsig(int signo)
+{
+ if (signo == SIGCHLD) {
+ gotsigchld = 1;
+ if (!trap[SIGCHLD])
+ return;
+ }
+
+ gotsig[signo - 1] = 1;
+ pendingsigs = signo;
+
+ if (signo == SIGINT && !trap[SIGINT]) {
+ if (!suppressint)
+ onint();
+ intpending = 1;
+ }
+}
+
+
+
+/*
+ * Called to execute a trap. Perhaps we should avoid entering new trap
+ * handlers while we are executing a trap handler.
+ */
+
+void dotrap(void)
+{
+ char *p;
+ char *q;
+ int i;
+ int savestatus;
+
+ savestatus = exitstatus;
+ pendingsigs = 0;
+ barrier();
+
+ for (i = 0, q = gotsig; i < NSIG - 1; i++, q++) {
+ if (!*q)
+ continue;
+ *q = 0;
+
+ p = trap[i + 1];
+ if (!p)
+ continue;
+ evalstring(p, 0);
+ exitstatus = savestatus;
+ if (evalskip)
+ break;
+ }
+}
+
+
+
+/*
+ * Controls whether the shell is interactive or not.
+ */
+
+
+void
+setinteractive(int on)
+{
+ static int is_interactive;
+
+ if (++on == is_interactive)
+ return;
+ is_interactive = on;
+ setsignal(SIGINT);
+ setsignal(SIGQUIT);
+ setsignal(SIGTERM);
+}
+
+
+
+/*
+ * Called to exit the shell.
+ */
+
+void
+exitshell(void)
+{
+ struct jmploc loc;
+ char *p;
+ volatile int status;
+
+#ifdef HETIO
+ hetio_reset_term();
+#endif
+ status = exitstatus;
+ TRACE(("pid %d, exitshell(%d)\n", getpid(), status));
+ if (setjmp(loc.loc)) {
+ if (exception == EXEXIT)
+ status = exitstatus;
+ goto out;
+ }
+ handler = &loc;
+ if ((p = trap[0])) {
+ trap[0] = NULL;
+ evalskip = 0;
+ evalstring(p, 0);
+ }
+out:
+ /*
+ * Disable job control so that whoever had the foreground before we
+ * started can get it back.
+ */
+ if (likely(!setjmp(loc.loc)))
+ setjobctl(0);
+ flushall();
+ _exit(status);
+ /* NOTREACHED */
+}
+
+/*
+ * Decode a signal name
+ */
+int decode_signal(const char *string, int minsig)
+{
+ int i;
+
+ if (is_number(string)) {
+ i = atoi(string);
+ if (i >= NSIG) {
+ return -1;
+ }
+ return i;
+ }
+
+ for ( i = minsig ; i < NSIG ; i++ ) {
+ if ( sys_sigabbrev[i] &&
+ !strcasecmp(string, sys_sigabbrev[i]) )
+ return i;
+ }
+
+#ifdef SIGRTMIN
+ if ( !strncasecmp(string, "RTMIN", 5) ) {
+ char *ep;
+
+ if ( string[5] && string[5] != '+' )
+ return -1;
+ i = SIGRTMIN + strtol(string+5, &ep, 10);
+ if ( *ep || i < SIGRTMIN || i > SIGRTMAX )
+ return -1;
+ return i;
+ }
+
+ if ( !strncasecmp(string, "RTMAX", 5) ) {
+ char *ep;
+
+ if ( string[5] && string[5] != '-' )
+ return -1;
+ i = SIGRTMAX + strtol(string+5, &ep, 10);
+ if ( *ep || i < SIGRTMIN || i > SIGRTMAX )
+ return -1;
+ return i;
+ }
+#endif
+
+ return -1;
+}
+
+/*
+ * Human-readable signal name
+ */
+const char *
+signal_name(int sig)
+{
+ static char buf[64];
+
+ if ( sig < 0 || sig >= NSIG ) {
+ return NULL;
+ } else if ( sys_sigabbrev[sig] ) {
+ return sys_sigabbrev[sig];
+#ifdef SIGRTMIN
+ } else if ( sig >= SIGRTMIN && sig <= SIGRTMAX ) {
+ snprintf(buf, sizeof buf, "RTMIN+%d", sig-SIGRTMIN);
+ return buf;
+#endif
+ } else {
+ snprintf(buf, sizeof buf, "%d", sig);
+ return buf;
+ }
+}