add help text
[oweals/busybox.git] / procps / kill.c
index 58dc8a98632dd3475dfc4f4272bc3171af159b78..6776d954641a516d2ce84dcaa1580a1696727acd 100644 (file)
-#include "internal.h"
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <signal.h>
-
-const char kill_usage[] = "kill [-signal] process-id [process-id ...]\n";
-
-struct signal_name {
-    const char *name;
-    int number;
-};
-
-const struct signal_name signames[] = {
-    {"HUP", SIGHUP},
-    {"INT", SIGINT},
-    {"QUIT", SIGQUIT},
-    {"ILL", SIGILL},
-    {"TRAP", SIGTRAP},
-    {"ABRT", SIGABRT},
-#ifndef __alpha__
-    {"IOT", SIGIOT},
-#endif
-#if defined(sparc) || defined(__alpha__)
-    {"EMT", SIGEMT},
-#else
-    {"BUS", SIGBUS},
-#endif
-    {"FPE", SIGFPE},
-    {"KILL", SIGKILL},
-#if defined(sparc) || defined(__alpha__)
-    {"BUS", SIGBUS},
-#else
-    {"USR1", SIGUSR1},
-#endif
-    {"SEGV", SIGSEGV},
-#if defined(sparc) || defined(__alpha__)
-    {"SYS", SIGSYS},
-#else
-    {"USR2", SIGUSR2},
-#endif
-    {"PIPE", SIGPIPE},
-    {"ALRM", SIGALRM},
-    {"TERM", SIGTERM},
-#if defined(sparc) || defined(__alpha__)
-    {"URG", SIGURG},
-    {"STOP", SIGSTOP},
-    {"TSTP", SIGTSTP},
-    {"CONT", SIGCONT},
-    {"CHLD", SIGCHLD},
-    {"TTIN", SIGTTIN},
-    {"TTOU", SIGTTOU},
-    {"IO", SIGIO},
-# ifndef __alpha__
-    {"POLL", SIGIO},
-# endif
-    {"XCPU", SIGXCPU},
-    {"XFSZ", SIGXFSZ},
-    {"VTALRM", SIGVTALRM},
-    {"PROF", SIGPROF},
-    {"WINCH", SIGWINCH},
-# ifdef __alpha__
-    {"INFO", SIGINFO},
-# else
-    {"LOST", SIGLOST},
-# endif
-    {"USR1", SIGUSR1},
-    {"USR2", SIGUSR2},
+/* vi: set sw=4 ts=4: */
+/*
+ * Mini kill/killall[5] implementation for busybox
+ *
+ * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+
+//usage:#define kill_trivial_usage
+//usage:       "[-l] [-SIG] PID..."
+//usage:#define kill_full_usage "\n\n"
+//usage:       "Send a signal (default: TERM) to given PIDs\n"
+//usage:     "\nOptions:"
+//usage:     "\n       -l      List all signal names and numbers"
+/* //usage:  "\n       -s SIG  Yet another way of specifying SIG" */
+//usage:
+//usage:#define kill_example_usage
+//usage:       "$ ps | grep apache\n"
+//usage:       "252 root     root     S [apache]\n"
+//usage:       "263 www-data www-data S [apache]\n"
+//usage:       "264 www-data www-data S [apache]\n"
+//usage:       "265 www-data www-data S [apache]\n"
+//usage:       "266 www-data www-data S [apache]\n"
+//usage:       "267 www-data www-data S [apache]\n"
+//usage:       "$ kill 252\n"
+//usage:
+//usage:#define killall_trivial_usage
+//usage:       "[-l] [-q] [-SIG] PROCESS_NAME..."
+//usage:#define killall_full_usage "\n\n"
+//usage:       "Send a signal (default: TERM) to given processes\n"
+//usage:     "\nOptions:"
+//usage:     "\n       -l      List all signal names and numbers"
+/* //usage:  "\n       -s SIG  Yet another way of specifying SIG" */
+//usage:     "\n       -q      Don't complain if no processes were killed"
+//usage:
+//usage:#define killall_example_usage
+//usage:       "$ killall apache\n"
+//usage:
+//usage:#define killall5_trivial_usage
+//usage:       "[-l] [-SIG] [-o PID]..."
+//usage:#define killall5_full_usage "\n\n"
+//usage:       "Send a signal (default: TERM) to all processes outside current session\n"
+//usage:     "\nOptions:"
+//usage:     "\n       -l      List all signal names and numbers"
+//usage:     "\n       -o PID  Don't signal this PID"
+/* //usage:  "\n       -s SIG  Yet another way of specifying SIG" */
+
+#include "libbb.h"
+
+/* Note: kill_main is directly called from shell in order to implement
+ * kill built-in. Shell substitutes job ids with process groups first.
+ *
+ * This brings some complications:
+ *
+ * + we can't use xfunc here
+ * + we can't use applet_name
+ * + we can't use bb_show_usage
+ * (Above doesn't apply for killall[5] cases)
+ *
+ * kill %n gets translated into kill ' -<process group>' by shell (note space!)
+ * This is needed to avoid collision with kill -9 ... syntax
+ */
+
+int kill_main(int argc, char **argv)
+{
+       char *arg;
+       pid_t pid;
+       int signo = SIGTERM, errors = 0, quiet = 0;
+#if !ENABLE_KILLALL && !ENABLE_KILLALL5
+#define killall 0
+#define killall5 0
 #else
-    {"STKFLT", SIGSTKFLT},
-    {"CHLD", SIGCHLD},
-    {"CONT", SIGCONT},
-    {"STOP", SIGSTOP},
-    {"TSTP", SIGTSTP},
-    {"TTIN", SIGTTIN},
-    {"TTOU", SIGTTOU},
-    {"URG", SIGURG},
-    {"XCPU", SIGXCPU},
-    {"XFSZ", SIGXFSZ},
-    {"VTALRM", SIGVTALRM},
-    {"PROF", SIGPROF},
-    {"WINCH", SIGWINCH},
-    {"IO", SIGIO},
-    {"POLL", SIGPOLL},
-    {"PWR", SIGPWR},
-    {"UNUSED", SIGUNUSED},
+/* How to determine who we are? find 3rd char from the end:
+ * kill, killall, killall5
+ *  ^i       ^a        ^l  - it's unique
+ * (checking from the start is complicated by /bin/kill... case) */
+       const char char3 = argv[0][strlen(argv[0]) - 3];
+#define killall (ENABLE_KILLALL && char3 == 'a')
+#define killall5 (ENABLE_KILLALL5 && char3 == 'l')
 #endif
-    {0, 0}
-};
 
-extern int kill_main (int argc, char **argv)
-{
-    int had_error = 0;
-    int sig = SIGTERM;
-
-
-
-    if (argv[1][0] == '-') {
-       if (argv[1][1] >= '0' && argv[1][1] <= '9') {
-           sig = atoi (&argv[1][1]);
-           if (sig < 0 || sig >= NSIG)
-               goto end;
-       } else {
-           const struct signal_name *s = signames;
-           for (;;) {
-               if (strcmp (s->name, &argv[1][1]) == 0) {
-                   sig = s->number;
-                   break;
+       /* Parse any options */
+       argc--;
+       arg = *++argv;
+
+       if (argc < 1 || arg[0] != '-') {
+               goto do_it_now;
+       }
+
+       /* The -l option, which prints out signal names.
+        * Intended usage in shell:
+        * echo "Died of SIG`kill -l $?`"
+        * We try to mimic what kill from coreutils-6.8 does */
+       if (arg[1] == 'l' && arg[2] == '\0') {
+               if (argc == 1) {
+                       /* Print the whole signal list */
+                       print_signames();
+                       return 0;
                }
-               s++;
-               if (s->name == 0)
-                   goto end;
-           }
+               /* -l <sig list> */
+               while ((arg = *++argv)) {
+                       if (isdigit(arg[0])) {
+                               signo = bb_strtou(arg, NULL, 10);
+                               if (errno) {
+                                       bb_error_msg("unknown signal '%s'", arg);
+                                       return EXIT_FAILURE;
+                               }
+                               /* Exitcodes >= 0x80 are to be treated
+                                * as "killed by signal (exitcode & 0x7f)" */
+                               puts(get_signame(signo & 0x7f));
+                               /* TODO: 'bad' signal# - coreutils says:
+                                * kill: 127: invalid signal
+                                * we just print "127" instead */
+                       } else {
+                               signo = get_signum(arg);
+                               if (signo < 0) {
+                                       bb_error_msg("unknown signal '%s'", arg);
+                                       return EXIT_FAILURE;
+                               }
+                               printf("%d\n", signo);
+                       }
+               }
+               /* If they specified -l, we are all done */
+               return EXIT_SUCCESS;
        }
-       argv++;
-       argc--;
 
-    }
-    while (argc > 1) {
-       int pid;
-       if (argv[1][0] < '0' || argv[1][0] > '9')
-           goto end;
-       pid = atoi (argv[1]);
-       if (kill (pid, sig) != 0) {
-           had_error = 1;
-           perror (argv[1]);
+       /* The -q quiet option */
+       if (killall && arg[1] == 'q' && arg[2] == '\0') {
+               quiet = 1;
+               arg = *++argv;
+               argc--;
+               if (argc < 1)
+                       bb_show_usage();
+               if (arg[0] != '-')
+                       goto do_it_now;
+       }
+
+       arg++; /* skip '-' */
+
+       /* -o PID? (if present, it always is at the end of command line) */
+       if (killall5 && arg[0] == 'o')
+               goto do_it_now;
+
+       if (argc > 1 && arg[0] == 's' && arg[1] == '\0') { /* -s SIG? */
+               argc--;
+               arg = *++argv;
+       } /* else it must be -SIG */
+       signo = get_signum(arg);
+       if (signo < 0) { /* || signo > MAX_SIGNUM ? */
+               bb_error_msg("bad signal name '%s'", arg);
+               return EXIT_FAILURE;
        }
-       argv++;
+       arg = *++argv;
        argc--;
-    }
-    if (had_error) {
-end:
-       fprintf(stderr, "Usage: %s\n", kill_usage);
-       exit ( FALSE);
-    }
-    exit (TRUE);
+
+ do_it_now:
+       pid = getpid();
+
+       if (killall5) {
+               pid_t sid;
+               procps_status_t* p = NULL;
+               int ret = 0;
+
+               /* Find out our session id */
+               sid = getsid(pid);
+               /* Stop all processes */
+               kill(-1, SIGSTOP);
+               /* Signal all processes except those in our session */
+               while ((p = procps_scan(p, PSSCAN_PID|PSSCAN_SID))) {
+                       int i;
+
+                       if (p->sid == (unsigned)sid
+                        || p->pid == (unsigned)pid
+                        || p->pid == 1)
+                               continue;
+
+                       /* All remaining args must be -o PID options.
+                        * Check p->pid against them. */
+                       for (i = 0; i < argc; i++) {
+                               pid_t omit;
+
+                               arg = argv[i];
+                               if (arg[0] != '-' || arg[1] != 'o') {
+                                       bb_error_msg("bad option '%s'", arg);
+                                       ret = 1;
+                                       goto resume;
+                               }
+                               arg += 2;
+                               if (!arg[0] && argv[++i])
+                                       arg = argv[i];
+                               omit = bb_strtoi(arg, NULL, 10);
+                               if (errno) {
+                                       bb_error_msg("invalid number '%s'", arg);
+                                       ret = 1;
+                                       goto resume;
+                               }
+                               if (p->pid == omit)
+                                       goto dont_kill;
+                       }
+                       kill(p->pid, signo);
+ dont_kill: ;
+               }
+ resume:
+               /* And let them continue */
+               kill(-1, SIGCONT);
+               return ret;
+       }
+
+       /* Pid or name is required for kill/killall */
+       if (argc < 1) {
+               bb_error_msg("you need to specify whom to kill");
+               return EXIT_FAILURE;
+       }
+
+       if (killall) {
+               /* Looks like they want to do a killall.  Do that */
+               while (arg) {
+                       pid_t* pidList;
+
+                       pidList = find_pid_by_name(arg);
+                       if (*pidList == 0) {
+                               errors++;
+                               if (!quiet)
+                                       bb_error_msg("%s: no process killed", arg);
+                       } else {
+                               pid_t *pl;
+
+                               for (pl = pidList; *pl; pl++) {
+                                       if (*pl == pid)
+                                               continue;
+                                       if (kill(*pl, signo) == 0)
+                                               continue;
+                                       errors++;
+                                       if (!quiet)
+                                               bb_perror_msg("can't kill pid %d", (int)*pl);
+                               }
+                       }
+                       free(pidList);
+                       arg = *++argv;
+               }
+               return errors;
+       }
+
+       /* Looks like they want to do a kill. Do that */
+       while (arg) {
+#if ENABLE_ASH || ENABLE_HUSH
+               /*
+                * We need to support shell's "hack formats" of
+                * " -PRGP_ID" (yes, with a leading space)
+                * and " PID1 PID2 PID3" (with degenerate case "")
+                */
+               while (*arg != '\0') {
+                       char *end;
+                       if (*arg == ' ')
+                               arg++;
+                       pid = bb_strtoi(arg, &end, 10);
+                       if (errno && (errno != EINVAL || *end != ' ')) {
+                               bb_error_msg("invalid number '%s'", arg);
+                               *end = '\0';
+                               errors++;
+                       } else if (kill(pid, signo) != 0) {
+                               bb_perror_msg("can't kill pid %d", (int)pid);
+                               errors++;
+                       }
+                       arg = end; /* can only point to ' ' or '\0' now */
+               }
+#else
+               pid = bb_strtoi(arg, NULL, 10);
+               if (errno) {
+                       bb_error_msg("invalid number '%s'", arg);
+                       errors++;
+               } else if (kill(pid, signo) != 0) {
+                       bb_perror_msg("can't kill pid %d", (int)pid);
+                       errors++;
+               }
+#endif
+               arg = *++argv;
+       }
+       return errors;
 }