procps/pidof.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * pidof implementation for busybox
   4  *
   5  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
   6  *
   7  * Licensed under GPLv2, see file LICENSE in this source tree.
   8  */
   9 //config:config PIDOF
  10 //config:       bool "pidof (6.6 kb)"
  11 //config:       default y
  12 //config:       help
  13 //config:       Pidof finds the process id's (pids) of the named programs. It prints
  14 //config:       those id's on the standard output.
  15 //config:
  16 //config:config FEATURE_PIDOF_SINGLE
  17 //config:       bool "Enable single shot (-s)"
  18 //config:       default y
  19 //config:       depends on PIDOF
  20 //config:       help
  21 //config:       Support '-s' for returning only the first pid found.
  22 //config:
  23 //config:config FEATURE_PIDOF_OMIT
  24 //config:       bool "Enable omitting pids (-o PID)"
  25 //config:       default y
  26 //config:       depends on PIDOF
  27 //config:       help
  28 //config:       Support '-o PID' for omitting the given pid(s) in output.
  29 //config:       The special pid %PPID can be used to name the parent process
  30 //config:       of the pidof, in other words the calling shell or shell script.
  31
  32 //applet:IF_PIDOF(APPLET(pidof, BB_DIR_BIN, BB_SUID_DROP))
  33 /* can't be noexec: can find _itself_ under wrong name, since after fork only,
  34  * /proc/PID/cmdline and comm are wrong! Can fix comm (prctl(PR_SET_NAME)),
  35  * but cmdline?
  36  */
  37
  38 //kbuild:lib-$(CONFIG_PIDOF) += pidof.o
  39
  40 //usage:#if (ENABLE_FEATURE_PIDOF_SINGLE || ENABLE_FEATURE_PIDOF_OMIT)
  41 //usage:#define pidof_trivial_usage
  42 //usage:       "[OPTIONS] [NAME]..."
  43 //usage:#define USAGE_PIDOF "\n"
  44 //usage:#else
  45 //usage:#define pidof_trivial_usage
  46 //usage:       "[NAME]..."
  47 //usage:#define USAGE_PIDOF /* none */
  48 //usage:#endif
  49 //usage:#define pidof_full_usage "\n\n"
  50 //usage:       "List PIDs of all processes with names that match NAMEs"
  51 //usage:        USAGE_PIDOF
  52 //usage:        IF_FEATURE_PIDOF_SINGLE(
  53 //usage:     "\n        -s      Show only one PID"
  54 //usage:        )
  55 //usage:        IF_FEATURE_PIDOF_OMIT(
  56 //usage:     "\n        -o PID  Omit given pid"
  57 //usage:     "\n                Use %PPID to omit pid of pidof's parent"
  58 //usage:        )
  59 //usage:
  60 //usage:#define pidof_example_usage
  61 //usage:       "$ pidof init\n"
  62 //usage:       "1\n"
  63 //usage:        IF_FEATURE_PIDOF_OMIT(
  64 //usage:       "$ pidof /bin/sh\n20351 5973 5950\n")
  65 //usage:        IF_FEATURE_PIDOF_OMIT(
  66 //usage:       "$ pidof /bin/sh -o %PPID\n20351 5950")
  67
  68 #include "libbb.h"
  69
  70 enum {
  71         IF_FEATURE_PIDOF_SINGLE(OPTBIT_SINGLE,)
  72         IF_FEATURE_PIDOF_OMIT(  OPTBIT_OMIT  ,)
  73         OPT_SINGLE = IF_FEATURE_PIDOF_SINGLE((1<<OPTBIT_SINGLE)) + 0,
  74         OPT_OMIT   = IF_FEATURE_PIDOF_OMIT(  (1<<OPTBIT_OMIT  )) + 0,
  75 };
  76
  77 int pidof_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  78 int pidof_main(int argc UNUSED_PARAM, char **argv)
  79 {
  80         unsigned first = 1;
  81         unsigned opt;
  82 #if ENABLE_FEATURE_PIDOF_OMIT
  83         llist_t *omits = NULL; /* list of pids to omit */
  84 #endif
  85
  86         /* do unconditional option parsing */
  87         opt = getopt32(argv, ""
  88                         IF_FEATURE_PIDOF_SINGLE ("s")
  89                         IF_FEATURE_PIDOF_OMIT("o:*", &omits));
  90
  91 #if ENABLE_FEATURE_PIDOF_OMIT
  92         /* fill omit list.  */
  93         {
  94                 llist_t *omits_p = omits;
  95                 while (1) {
  96                         omits_p = llist_find_str(omits_p, "%PPID");
  97                         if (!omits_p)
  98                                 break;
  99                         /* are we asked to exclude the parent's process ID?  */
 100                         omits_p->data = utoa((unsigned)getppid());
 101                 }
 102         }
 103 #endif
 104         /* Looks like everything is set to go.  */
 105         argv += optind;
 106         while (*argv) {
 107                 pid_t *pidList;
 108                 pid_t *pl;
 109
 110                 /* reverse the pidlist like GNU pidof does.  */
 111                 pidList = pidlist_reverse(find_pid_by_name(*argv));
 112                 for (pl = pidList; *pl; pl++) {
 113 #if ENABLE_FEATURE_PIDOF_OMIT
 114                         if (opt & OPT_OMIT) {
 115                                 llist_t *omits_p = omits;
 116                                 while (omits_p) {
 117                                         if (xatoul(omits_p->data) == (unsigned long)(*pl)) {
 118                                                 goto omitting;
 119                                         }
 120                                         omits_p = omits_p->link;
 121                                 }
 122                         }
 123 #endif
 124                         printf(" %u" + first, (unsigned)*pl);
 125                         first = 0;
 126                         if (ENABLE_FEATURE_PIDOF_SINGLE && (opt & OPT_SINGLE))
 127                                 break;
 128 #if ENABLE_FEATURE_PIDOF_OMIT
 129  omitting: ;
 130 #endif
 131                 }
 132                 free(pidList);
 133                 argv++;
 134         }
 135         if (!first)
 136                 bb_putchar('\n');
 137
 138 #if ENABLE_FEATURE_PIDOF_OMIT
 139         if (ENABLE_FEATURE_CLEAN_UP)
 140                 llist_free(omits, NULL);
 141 #endif
 142         return first; /* 1 (failure) - no processes found */
 143 }