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