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 (6.5 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 (7.5 kb)"
17 //config: default y
18 //config: help
19 //config: Send signals to processes by name.
20
21 //applet:IF_PGREP(APPLET_ODDNAME(pgrep, pgrep, BB_DIR_USR_BIN, BB_SUID_DROP, pgrep))
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 /* can't be noexec: can find _itself_ under wrong name, since after fork only,
25 * /proc/PID/cmdline and comm are wrong! Can fix comm (prctl(PR_SET_NAME)),
26 * but cmdline?
27 */
28
29 //kbuild:lib-$(CONFIG_PGREP) += pgrep.o
30 //kbuild:lib-$(CONFIG_PKILL) += pgrep.o
31
32 //usage:#define pgrep_trivial_usage
33 //usage: "[-flanovx] [-s SID|-P PPID|PATTERN]"
34 //usage:#define pgrep_full_usage "\n\n"
35 //usage: "Display process(es) selected by regex PATTERN\n"
36 //usage: "\n -l Show command name too"
37 //usage: "\n -a Show command line too"
38 //usage: "\n -f Match against entire command line"
39 //usage: "\n -n Show the newest process only"
40 //usage: "\n -o Show the oldest process only"
41 //usage: "\n -v Negate the match"
42 //usage: "\n -x Match whole name (not substring)"
43 //usage: "\n -s Match session ID (0 for current)"
44 //usage: "\n -P Match parent process ID"
45 //usage:
46 //usage:#define pkill_trivial_usage
47 //usage: "[-l|-SIGNAL] [-xfvno] [-s SID|-P PPID|PATTERN]"
48 //usage:#define pkill_full_usage "\n\n"
49 //usage: "Send signal to processes selected by regex PATTERN\n"
50 //usage: "\n -l List all signals"
51 //usage: "\n -x Match whole name (not substring)"
52 //usage: "\n -f Match against entire command line"
53 //usage: "\n -s SID Match session ID (0 for current)"
54 //usage: "\n -P PPID Match parent process ID"
55 //usage: "\n -v Negate the match"
56 //usage: "\n -n Signal the newest process only"
57 //usage: "\n -o Signal the oldest process only"
58
59 #include "libbb.h"
60 #include "xregex.h"
61
62 /* Idea taken from kill.c */
63 #define pgrep (ENABLE_PGREP && (!ENABLE_PKILL || applet_name[1] == 'g'))
64 #define pkill (ENABLE_PKILL && (!ENABLE_PGREP || applet_name[1] == 'k'))
65
66 enum {
67 /* "vlafxons:+P:+" */
68 OPTBIT_V = 0, /* must be first, we need OPT_INVERT = 0/1 */
69 OPTBIT_L,
70 OPTBIT_A,
71 OPTBIT_F,
72 OPTBIT_X,
73 OPTBIT_O,
74 OPTBIT_N,
75 OPTBIT_S,
76 OPTBIT_P,
77 };
78
79 #define OPT_INVERT (opt & (1 << OPTBIT_V))
80 #define OPT_LIST (opt & (1 << OPTBIT_L))
81 #define OPT_LISTFULL (opt & (1 << OPTBIT_A))
82 #define OPT_FULL (opt & (1 << OPTBIT_F))
83 #define OPT_ANCHOR (opt & (1 << OPTBIT_X))
84 #define OPT_FIRST (opt & (1 << OPTBIT_O))
85 #define OPT_LAST (opt & (1 << OPTBIT_N))
86 #define OPT_SID (opt & (1 << OPTBIT_S))
87 #define OPT_PPID (opt & (1 << OPTBIT_P))
88
act(unsigned pid,char * cmd,int signo)89 static void act(unsigned pid, char *cmd, int signo)
90 {
91 if (pgrep) {
92 if (option_mask32 & ((1 << OPTBIT_L)|(1 << OPTBIT_A))) /* -l or -a */
93 printf("%u %s\n", pid, cmd);
94 else
95 printf("%u\n", pid);
96 } else
97 kill(pid, signo);
98 }
99
100 int pgrep_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
pgrep_main(int argc UNUSED_PARAM,char ** argv)101 int pgrep_main(int argc UNUSED_PARAM, char **argv)
102 {
103 unsigned pid;
104 int signo;
105 unsigned opt;
106 int scan_mask;
107 int matched_pid;
108 int sid2match, ppid2match;
109 char *cmd_last;
110 procps_status_t *proc;
111 /* These are initialized to 0 */
112 struct {
113 regex_t re_buffer;
114 regmatch_t re_match[1];
115 } Z;
116 #define re_buffer (Z.re_buffer)
117 #define re_match (Z.re_match )
118
119 memset(&Z, 0, sizeof(Z));
120
121 /* Parse -SIGNAL for pkill. Must be first option, if present */
122 signo = SIGTERM;
123 if (pkill && argv[1] && argv[1][0] == '-') {
124 int temp = get_signum(argv[1]+1);
125 if (temp != -1) {
126 signo = temp;
127 argv++;
128 }
129 }
130
131 /* Parse remaining options */
132 ppid2match = -1;
133 sid2match = -1;
134 opt = getopt32(argv, "vlafxons:+P:+", &sid2match, &ppid2match);
135 argv += optind;
136
137 if (pkill && OPT_LIST) { /* -l: print the whole signal list */
138 print_signames();
139 return 0;
140 }
141
142 pid = getpid();
143 if (sid2match == 0)
144 sid2match = getsid(pid);
145
146 scan_mask = PSSCAN_COMM | PSSCAN_ARGV0;
147 if (OPT_FULL)
148 scan_mask |= PSSCAN_ARGVN;
149
150 /* One pattern is required, if no -s and no -P */
151 if ((sid2match & ppid2match) < 0 && (!argv[0] || argv[1]))
152 bb_show_usage();
153
154 if (argv[0])
155 xregcomp(&re_buffer, argv[0], OPT_ANCHOR ? REG_EXTENDED : (REG_EXTENDED|REG_NOSUB));
156
157 matched_pid = 0;
158 cmd_last = NULL;
159 proc = NULL;
160 while ((proc = procps_scan(proc, scan_mask)) != NULL) {
161 char *cmd;
162 int cmdlen, match;
163
164 if (proc->pid == pid)
165 continue;
166
167 if (!OPT_INVERT) {
168 /* Quickly reject -sN -PN mismatches... unless -v */
169 if (ppid2match >= 0 && ppid2match != proc->ppid)
170 continue;
171 if (sid2match >= 0 && sid2match != proc->sid)
172 continue;
173 }
174
175 cmdlen = -1;
176 cmd = proc->argv0;
177 if (!cmd) {
178 cmd = proc->comm;
179 } else {
180 int i = proc->argv_len;
181
182 if (!OPT_LISTFULL)
183 cmdlen = strlen(cmd); /* not -a: find first NUL */
184 /*
185 * "sleep 11" looks like "sleep""\0""11""\0" in argv0.
186 * Make sure last "\0" does not get converted to " ":
187 */
188 if (i && cmd[i-1] == '\0')
189 i--;
190 while (--i >= 0) {
191 if ((unsigned char)cmd[i] < ' ')
192 cmd[i] = ' ';
193 }
194 }
195
196 if (OPT_INVERT) {
197 /* "pgrep -v -P1 firefox" means "not (ppid=1 AND name=firefox)"
198 * or equivalently "ppid!=1 OR name!=firefox".
199 * Check the first condition and if true, skip matching.
200 */
201 if (ppid2match >= 0 && ppid2match != proc->ppid)
202 goto got_it;
203 if (sid2match >= 0 && sid2match != proc->sid)
204 goto got_it;
205 }
206
207 match = !argv[0]; /* if no PATTERN, then it's a match, else... */
208 if (!match) {
209 again:
210 match = (regexec(&re_buffer, cmd, 1, re_match, 0) == 0);
211 if (!match && cmd != proc->comm) {
212 /* if argv[] did not match, try comm */
213 cmdlen = -1;
214 cmd = proc->comm;
215 goto again;
216 }
217 if (match && OPT_ANCHOR) {
218 /* -x requires full string match */
219 match = (re_match[0].rm_so == 0 && cmd[re_match[0].rm_eo] == '\0');
220 }
221 }
222
223 /* NB: OPT_INVERT is always 0 or 1 */
224 if (match ^ OPT_INVERT) {
225 got_it:
226 matched_pid = proc->pid;
227 if (OPT_LAST) {
228 free(cmd_last);
229 cmd_last = xstrdup(cmd);
230 continue;
231 }
232 if (cmdlen >= 0)
233 cmd[cmdlen] = '\0';
234 act(proc->pid, cmd, signo);
235 if (OPT_FIRST)
236 break;
237 }
238 }
239
240 if (cmd_last) {
241 act(matched_pid, cmd_last, signo);
242 if (ENABLE_FEATURE_CLEAN_UP)
243 free(cmd_last);
244 }
245 return matched_pid == 0; /* return 1 if no processes listed/signaled */
246 }
247