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 (6.8 kb)"
  11 //config:       default y
  12 //config:       help
  13 //config:         Look for processes by name.
  14 //config:
  15 //config:config PKILL
  16 //config:       bool "pkill (7.6 kb)"
  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:       "[-flanovx] [-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        -a      Show command line too"
  34 //usage:     "\n        -f      Match against entire command line"
  35 //usage:     "\n        -n      Show the newest process only"
  36 //usage:     "\n        -o      Show the oldest process only"
  37 //usage:     "\n        -v      Negate the match"
  38 //usage:     "\n        -x      Match whole name (not substring)"
  39 //usage:     "\n        -s      Match session ID (0 for current)"
  40 //usage:     "\n        -P      Match parent process ID"
  41 //usage:
  42 //usage:#define pkill_trivial_usage
  43 //usage:       "[-l|-SIGNAL] [-fnovx] [-s SID|-P PPID|PATTERN]"
  44 //usage:#define pkill_full_usage "\n\n"
  45 //usage:       "Send a signal to process(es) selected by regex PATTERN\n"
  46 //usage:     "\n        -l      List all signals"
  47 //usage:     "\n        -f      Match against entire command line"
  48 //usage:     "\n        -n      Signal the newest process only"
  49 //usage:     "\n        -o      Signal the oldest process only"
  50 //usage:     "\n        -v      Negate the match"
  51 //usage:     "\n        -x      Match whole name (not substring)"
  52 //usage:     "\n        -s      Match session ID (0 for current)"
  53 //usage:     "\n        -P      Match parent process ID"
  54
  55 #include "libbb.h"
  56 #include "xregex.h"
  57
  58 /* Idea taken from kill.c */
  59 #define pgrep (ENABLE_PGREP && (!ENABLE_PKILL || applet_name[1] == 'g'))
  60 #define pkill (ENABLE_PKILL && (!ENABLE_PGREP || applet_name[1] == 'k'))
  61
  62 enum {
  63         /* "vlafxons:+P:+" */
  64         OPTBIT_V = 0, /* must be first, we need OPT_INVERT = 0/1 */
  65         OPTBIT_L,
  66         OPTBIT_A,
  67         OPTBIT_F,
  68         OPTBIT_X,
  69         OPTBIT_O,
  70         OPTBIT_N,
  71         OPTBIT_S,
  72         OPTBIT_P,
  73 };
  74
  75 #define OPT_INVERT      (opt & (1 << OPTBIT_V))
  76 #define OPT_LIST        (opt & (1 << OPTBIT_L))
  77 #define OPT_LISTFULL    (opt & (1 << OPTBIT_A))
  78 #define OPT_FULL        (opt & (1 << OPTBIT_F))
  79 #define OPT_ANCHOR      (opt & (1 << OPTBIT_X))
  80 #define OPT_FIRST       (opt & (1 << OPTBIT_O))
  81 #define OPT_LAST        (opt & (1 << OPTBIT_N))
  82 #define OPT_SID         (opt & (1 << OPTBIT_S))
  83 #define OPT_PPID        (opt & (1 << OPTBIT_P))
  84
  85 static void act(unsigned pid, char *cmd, int signo)
  86 {
  87         if (pgrep) {
  88                 if (option_mask32 & ((1 << OPTBIT_L)|(1 << OPTBIT_A))) /* -l or -a */
  89                         printf("%u %s\n", pid, cmd);
  90                 else
  91                         printf("%u\n", pid);
  92         } else
  93                 kill(pid, signo);
  94 }
  95
  96 int pgrep_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  97 int pgrep_main(int argc UNUSED_PARAM, char **argv)
  98 {
  99         unsigned pid;
 100         int signo;
 101         unsigned opt;
 102         int scan_mask;
 103         int matched_pid;
 104         int sid2match, ppid2match;
 105         char *cmd_last;
 106         procps_status_t *proc;
 107         /* These are initialized to 0 */
 108         struct {
 109                 regex_t re_buffer;
 110                 regmatch_t re_match[1];
 111         } Z;
 112 #define re_buffer (Z.re_buffer)
 113 #define re_match  (Z.re_match )
 114
 115         memset(&Z, 0, sizeof(Z));
 116
 117         /* Parse -SIGNAL for pkill. Must be first option, if present */
 118         signo = SIGTERM;
 119         if (pkill && argv[1] && argv[1][0] == '-') {
 120                 int temp = get_signum(argv[1]+1);
 121                 if (temp != -1) {
 122                         signo = temp;
 123                         argv++;
 124                 }
 125         }
 126
 127         /* Parse remaining options */
 128         ppid2match = -1;
 129         sid2match = -1;
 130         opt = getopt32(argv, "vlafxons:+P:+", &sid2match, &ppid2match);
 131         argv += optind;
 132
 133         if (pkill && OPT_LIST) { /* -l: print the whole signal list */
 134                 print_signames();
 135                 return 0;
 136         }
 137
 138         pid = getpid();
 139         if (sid2match == 0)
 140                 sid2match = getsid(pid);
 141
 142         scan_mask = PSSCAN_COMM | PSSCAN_ARGV0;
 143         if (OPT_FULL)
 144                 scan_mask |= PSSCAN_ARGVN;
 145
 146         /* One pattern is required, if no -s and no -P */
 147         if ((sid2match & ppid2match) < 0 && (!argv[0] || argv[1]))
 148                 bb_show_usage();
 149
 150         if (argv[0])
 151                 xregcomp(&re_buffer, argv[0], OPT_ANCHOR ? REG_EXTENDED : (REG_EXTENDED|REG_NOSUB));
 152
 153         matched_pid = 0;
 154         cmd_last = NULL;
 155         proc = NULL;
 156         while ((proc = procps_scan(proc, scan_mask)) != NULL) {
 157                 char *cmd;
 158                 int cmdlen;
 159
 160                 if (proc->pid == pid)
 161                         continue;
 162
 163                 if (ppid2match >= 0 && ppid2match != proc->ppid)
 164                         continue;
 165                 if (sid2match >= 0 && sid2match != proc->sid)
 166                         continue;
 167
 168                 cmdlen = -1;
 169                 cmd = proc->argv0;
 170                 if (!cmd) {
 171                         cmd = proc->comm;
 172                 } else {
 173                         int i = proc->argv_len;
 174
 175                         if (!OPT_LISTFULL)
 176                                 cmdlen = strlen(cmd); /* not -a: find first NUL */
 177                         /*
 178                          * "sleep 11" looks like "sleep""\0""11""\0" in argv0.
 179                          * Make sure last "\0" does not get converted to " ":
 180                          */
 181                         if (i && cmd[i-1] == '\0')
 182                                 i--;
 183                         while (--i >= 0) {
 184                                 if ((unsigned char)cmd[i] < ' ')
 185                                         cmd[i] = ' ';
 186                         }
 187                 }
 188
 189                 /* NB: OPT_INVERT is always 0 or 1 */
 190                 if (!argv[0]
 191                  || (regexec(&re_buffer, cmd, 1, re_match, 0) == 0 /* match found */
 192                     && (!OPT_ANCHOR || (re_match[0].rm_so == 0 && re_match[0].rm_eo == (regoff_t)strlen(cmd)))
 193                     ) ^ OPT_INVERT
 194                 ) {
 195                         matched_pid = proc->pid;
 196                         if (OPT_LAST) {
 197                                 free(cmd_last);
 198                                 cmd_last = xstrdup(cmd);
 199                                 continue;
 200                         }
 201                         if (cmdlen >= 0)
 202                                 cmd[cmdlen] = '\0';
 203                         act(proc->pid, cmd, signo);
 204                         if (OPT_FIRST)
 205                                 break;
 206                 }
 207         }
 208
 209         if (cmd_last) {
 210                 act(matched_pid, cmd_last, signo);
 211                 if (ENABLE_FEATURE_CLEAN_UP)
 212                         free(cmd_last);
 213         }
 214         return matched_pid == 0; /* return 1 if no processes listed/signaled */
 215 }