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