LXR busybox/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
  43enum {
  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
  64static void act(unsigned pid, char *cmd, int signo)
  65{
  66        if (pgrep) {
  67                if (option_mask32 & (1 << OPTBIT_L)) /* OPT_LIST */
  68                        printf("%d %s\n", pid, cmd);
  69                else
  70                        printf("%d\n", pid);
  71        } else
  72                kill(pid, signo);
  73}
  74
  75int pgrep_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  76int 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], 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}
 183