procps/pgrep.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini pgrep/pkill implementation for busybox
   4  *
   5  * Copyright (C) 2007 Loic Grenie <loic.grenie@gmail.com>
   6  *
   7  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8  */
   9 //config:config PGREP
  10 //config:       bool "pgrep"
  11 //config:       default y
  12 //config:       help
  13 //config:         Look for processes by name.
  14 //config:
  15 //config:config PKILL
  16 //config:       bool "pkill"
  17 //config:       default y
  18 //config:       help
  19 //config:         Send signals to processes by name.
  20
  21 //applet:IF_PGREP(APPLET(pgrep, BB_DIR_USR_BIN, BB_SUID_DROP))
  22 //                APPLET_ODDNAME:name   main   location        suid_type     help
  23 //applet:IF_PKILL(APPLET_ODDNAME(pkill, pgrep, BB_DIR_USR_BIN, BB_SUID_DROP, pkill))
  24
  25 //kbuild:lib-$(CONFIG_PGREP) += pgrep.o
  26 //kbuild:lib-$(CONFIG_PKILL) += pgrep.o
  27
  28 //usage:#define pgrep_trivial_usage
  29 //usage:       "[-flnovx] [-s SID|-P PPID|PATTERN]"
  30 //usage:#define pgrep_full_usage "\n\n"
  31 //usage:       "Display process(es) selected by regex PATTERN\n"
  32 //usage:     "\n        -l      Show command name too"
  33 //usage:     "\n        -f      Match against entire command line"
  34 //usage:     "\n        -n      Show the newest process only"
  35 //usage:     "\n        -o      Show the oldest process only"
  36 //usage:     "\n        -v      Negate the match"
  37 //usage:     "\n        -x      Match whole name (not substring)"
  38 //usage:     "\n        -s      Match session ID (0 for current)"
  39 //usage:     "\n        -P      Match parent process ID"
  40 //usage:
  41 //usage:#define pkill_trivial_usage
  42 //usage:       "[-l|-SIGNAL] [-fnovx] [-s SID|-P PPID|PATTERN]"
  43 //usage:#define pkill_full_usage "\n\n"
  44 //usage:       "Send a signal to process(es) selected by regex PATTERN\n"
  45 //usage:     "\n        -l      List all signals"
  46 //usage:     "\n        -f      Match against entire command line"
  47 //usage:     "\n        -n      Signal the newest process only"
  48 //usage:     "\n        -o      Signal the oldest process only"
  49 //usage:     "\n        -v      Negate the match"
  50 //usage:     "\n        -x      Match whole name (not substring)"
  51 //usage:     "\n        -s      Match session ID (0 for current)"
  52 //usage:     "\n        -P      Match parent process ID"
  53
  54 #include "libbb.h"
  55 #include "xregex.h"
  56
  57 /* Idea taken from kill.c */
  58 #define pgrep (ENABLE_PGREP && applet_name[1] == 'g')
  59 #define pkill (ENABLE_PKILL && applet_name[1] == 'k')
  60
  61 enum {
  62         /* "vlfxons:P:" */
  63         OPTBIT_V = 0, /* must be first, we need OPT_INVERT = 0/1 */
  64         OPTBIT_L,
  65         OPTBIT_F,
  66         OPTBIT_X,
  67         OPTBIT_O,
  68         OPTBIT_N,
  69         OPTBIT_S,
  70         OPTBIT_P,
  71 };
  72
  73 #define OPT_INVERT      (opt & (1 << OPTBIT_V))
  74 #define OPT_LIST        (opt & (1 << OPTBIT_L))
  75 #define OPT_FULL        (opt & (1 << OPTBIT_F))
  76 #define OPT_ANCHOR      (opt & (1 << OPTBIT_X))
  77 #define OPT_FIRST       (opt & (1 << OPTBIT_O))
  78 #define OPT_LAST        (opt & (1 << OPTBIT_N))
  79 #define OPT_SID         (opt & (1 << OPTBIT_S))
  80 #define OPT_PPID        (opt & (1 << OPTBIT_P))
  81
  82 static void act(unsigned pid, char *cmd, int signo)
  83 {
  84         if (pgrep) {
  85                 if (option_mask32 & (1 << OPTBIT_L)) /* OPT_LIST */
  86                         printf("%u %s\n", pid, cmd);
  87                 else
  88                         printf("%u\n", pid);
  89         } else
  90                 kill(pid, signo);
  91 }
  92
  93 int pgrep_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  94 int pgrep_main(int argc UNUSED_PARAM, char **argv)
  95 {
  96         unsigned pid;
  97         int signo;
  98         unsigned opt;
  99         int scan_mask;
 100         int matched_pid;
 101         int sid2match, ppid2match;
 102         char *cmd_last;
 103         procps_status_t *proc;
 104         /* These are initialized to 0 */
 105         struct {
 106                 regex_t re_buffer;
 107                 regmatch_t re_match[1];
 108         } Z;
 109 #define re_buffer (Z.re_buffer)
 110 #define re_match  (Z.re_match )
 111
 112         memset(&Z, 0, sizeof(Z));
 113
 114         /* Parse -SIGNAL for pkill. Must be first option, if present */
 115         signo = SIGTERM;
 116         if (pkill && argv[1] && argv[1][0] == '-') {
 117                 int temp = get_signum(argv[1]+1);
 118                 if (temp != -1) {
 119                         signo = temp;
 120                         argv++;
 121                 }
 122         }
 123
 124         /* Parse remaining options */
 125         ppid2match = -1;
 126         sid2match = -1;
 127         opt = getopt32(argv, "vlfxons:+P:+", &sid2match, &ppid2match);
 128         argv += optind;
 129
 130         if (pkill && OPT_LIST) { /* -l: print the whole signal list */
 131                 print_signames();
 132                 return 0;
 133         }
 134
 135         pid = getpid();
 136         if (sid2match == 0)
 137                 sid2match = getsid(pid);
 138
 139         scan_mask = PSSCAN_COMM | PSSCAN_ARGV0;
 140         if (OPT_FULL)
 141                 scan_mask |= PSSCAN_ARGVN;
 142
 143         /* One pattern is required, if no -s and no -P */
 144         if ((sid2match & ppid2match) < 0 && (!argv[0] || argv[1]))
 145                 bb_show_usage();
 146
 147         if (argv[0])
 148                 xregcomp(&re_buffer, argv[0], OPT_ANCHOR ? REG_EXTENDED : (REG_EXTENDED|REG_NOSUB));
 149
 150         matched_pid = 0;
 151         cmd_last = NULL;
 152         proc = NULL;
 153         while ((proc = procps_scan(proc, scan_mask)) != NULL) {
 154                 char *cmd;
 155
 156                 if (proc->pid == pid)
 157                         continue;
 158
 159                 cmd = proc->argv0;
 160                 if (!cmd) {
 161                         cmd = proc->comm;
 162                 } else {
 163                         int i = proc->argv_len;
 164                         while (--i >= 0) {
 165                                 if ((unsigned char)cmd[i] < ' ')
 166                                         cmd[i] = ' ';
 167                         }
 168                 }
 169
 170                 if (ppid2match >= 0 && ppid2match != proc->ppid)
 171                         continue;
 172                 if (sid2match >= 0 && sid2match != proc->sid)
 173                         continue;
 174
 175                 /* NB: OPT_INVERT is always 0 or 1 */
 176                 if (!argv[0]
 177                  || (regexec(&re_buffer, cmd, 1, re_match, 0) == 0 /* match found */
 178                     && (!OPT_ANCHOR || (re_match[0].rm_so == 0 && re_match[0].rm_eo == (regoff_t)strlen(cmd)))
 179                     ) ^ OPT_INVERT
 180                 ) {
 181                         matched_pid = proc->pid;
 182                         if (OPT_LAST) {
 183                                 free(cmd_last);
 184                                 cmd_last = xstrdup(cmd);
 185                                 continue;
 186                         }
 187                         act(proc->pid, cmd, signo);
 188                         if (OPT_FIRST)
 189                                 break;
 190                 }
 191         }
 192
 193         if (cmd_last) {
 194                 act(matched_pid, cmd_last, signo);
 195                 if (ENABLE_FEATURE_CLEAN_UP)
 196                         free(cmd_last);
 197         }
 198         return matched_pid == 0; /* return 1 if no processes listed/signaled */
 199 }