1/* vi: set sw=4 ts=4: */ 2/* 3 * Mini kill/killall[5] implementation for busybox 4 * 5 * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>. 6 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org> 7 * 8 * Licensed under GPLv2 or later, see file LICENSE in this source tree. 9 */ 10//config:config KILL 11//config: bool "kill (3.1 kb)" 12//config: default y 13//config: help 14//config: The command kill sends the specified signal to the specified 15//config: process or process group. If no signal is specified, the TERM 16//config: signal is sent. 17//config: 18//config:config KILLALL 19//config: bool "killall (5.6 kb)" 20//config: default y 21//config: help 22//config: killall sends a signal to all processes running any of the 23//config: specified commands. If no signal name is specified, SIGTERM is 24//config: sent. 25//config: 26//config:config KILLALL5 27//config: bool "killall5 (5.3 kb)" 28//config: default y 29//config: help 30//config: The SystemV killall command. killall5 sends a signal 31//config: to all processes except kernel threads and the processes 32//config: in its own session, so it won't kill the shell that is running 33//config: the script it was called from. 34 35//applet:IF_KILL( APPLET_NOFORK(kill, kill, BB_DIR_BIN, BB_SUID_DROP, kill)) 36// APPLET_NOFORK:name main location suid_type help 37//applet:IF_KILLALL( APPLET_NOFORK(killall, kill, BB_DIR_USR_BIN, BB_SUID_DROP, killall)) 38//applet:IF_KILLALL5(APPLET_NOFORK(killall5, kill, BB_DIR_USR_SBIN, BB_SUID_DROP, killall5)) 39 40//kbuild:lib-$(CONFIG_KILL) += kill.o 41//kbuild:lib-$(CONFIG_KILLALL) += kill.o 42//kbuild:lib-$(CONFIG_KILLALL5) += kill.o 43 44//usage:#define kill_trivial_usage 45//usage: "[-l] [-SIG] PID..." 46//usage:#define kill_full_usage "\n\n" 47//usage: "Send a signal (default: TERM) to given PIDs\n" 48//usage: "\n -l List all signal names and numbers" 49/* //usage: "\n -s SIG Yet another way of specifying SIG" */ 50//usage: 51//usage:#define kill_example_usage 52//usage: "$ ps | grep apache\n" 53//usage: "252 root root S [apache]\n" 54//usage: "263 www-data www-data S [apache]\n" 55//usage: "264 www-data www-data S [apache]\n" 56//usage: "265 www-data www-data S [apache]\n" 57//usage: "266 www-data www-data S [apache]\n" 58//usage: "267 www-data www-data S [apache]\n" 59//usage: "$ kill 252\n" 60//usage: 61//usage:#define killall_trivial_usage 62//usage: "[-l] [-q] [-SIG] PROCESS_NAME..." 63//usage:#define killall_full_usage "\n\n" 64//usage: "Send a signal (default: TERM) to given processes\n" 65//usage: "\n -l List all signal names and numbers" 66/* //usage: "\n -s SIG Yet another way of specifying SIG" */ 67//usage: "\n -q Don't complain if no processes were killed" 68//usage: 69//usage:#define killall_example_usage 70//usage: "$ killall apache\n" 71//usage: 72//usage:#define killall5_trivial_usage 73//usage: "[-l] [-SIG] [-o PID]..." 74//usage:#define killall5_full_usage "\n\n" 75//usage: "Send a signal (default: TERM) to all processes outside current session\n" 76//usage: "\n -l List all signal names and numbers" 77//usage: "\n -o PID Don't signal this PID" 78/* //usage: "\n -s SIG Yet another way of specifying SIG" */ 79 80#include "libbb.h" 81 82/* Note: kill_main is directly called from shell in order to implement 83 * kill built-in. Shell substitutes job ids with process groups first. 84 * 85 * This brings some complications: 86 * 87 * + we can't use xfunc here 88 * + we can't use applet_name 89 * + we can't use bb_show_usage 90 * (doesn't apply for killall[5], still should be careful b/c NOFORK) 91 * 92 * kill %n gets translated into kill ' -<process group>' by shell (note space!) 93 * This is needed to avoid collision with kill -9 ... syntax 94 */ 95 96//kbuild:lib-$(CONFIG_ASH_JOB_CONTROL) += kill.o 97//kbuild:lib-$(CONFIG_HUSH_KILL) += kill.o 98 99#define SH_KILL (ENABLE_ASH_JOB_CONTROL || ENABLE_HUSH_KILL) 100/* If shells want to have "kill", for ifdefs it's like ENABLE_KILL=1 */ 101#if SH_KILL 102# undef ENABLE_KILL 103# define ENABLE_KILL 1 104#endif 105#define KILL_APPLET_CNT (ENABLE_KILL + ENABLE_KILLALL + ENABLE_KILLALL5) 106 107int kill_main(int argc UNUSED_PARAM, char **argv) 108{ 109 char *arg; 110 pid_t pid; 111 int signo = SIGTERM, errors = 0; 112#if ENABLE_KILL || ENABLE_KILLALL 113 int quiet = 0; 114#endif 115 116#if KILL_APPLET_CNT == 1 117# define is_killall ENABLE_KILLALL 118# define is_killall5 ENABLE_KILLALL5 119#else 120/* How to determine who we are? find 3rd char from the end: 121 * kill, killall, killall5 122 * ^i ^a ^l - it's unique 123 * (checking from the start is complicated by /bin/kill... case) */ 124 const char char3 = argv[0][strlen(argv[0]) - 3]; 125# define is_killall (ENABLE_KILLALL && char3 == 'a') 126# define is_killall5 (ENABLE_KILLALL5 && char3 == 'l') 127#endif 128 129 /* Parse any options */ 130 arg = *++argv; 131 132 if (!arg || arg[0] != '-') { 133 goto do_it_now; 134 } 135 136 /* The -l option, which prints out signal names. 137 * Intended usage in shell: 138 * echo "Died of SIG`kill -l $?`" 139 * We try to mimic what kill from coreutils-6.8 does */ 140 if (arg[1] == 'l' && arg[2] == '\0') { 141 arg = *++argv; 142 if (!arg) { 143 /* Print the whole signal list */ 144 print_signames(); 145 return 0; 146 } 147 /* -l <sig list> */ 148 do { 149 if (isdigit(arg[0])) { 150 signo = bb_strtou(arg, NULL, 10); 151 if (errno) { 152 bb_error_msg("unknown signal '%s'", arg); 153 return EXIT_FAILURE; 154 } 155 /* Exitcodes >= 0x80 are to be treated 156 * as "killed by signal (exitcode & 0x7f)" */ 157 puts(get_signame(signo & 0x7f)); 158 /* TODO: 'bad' signal# - coreutils says: 159 * kill: 127: invalid signal 160 * we just print "127" instead */ 161 } else { 162 signo = get_signum(arg); 163 if (signo < 0) { 164 bb_error_msg("unknown signal '%s'", arg); 165 return EXIT_FAILURE; 166 } 167 printf("%d\n", signo); 168 } 169 arg = *++argv; 170 } while (arg); 171 return EXIT_SUCCESS; 172 } 173 174 /* The -q quiet option */ 175 if (is_killall && arg[1] == 'q' && arg[2] == '\0') { 176#if ENABLE_KILL || ENABLE_KILLALL 177 quiet = 1; 178#endif 179 arg = *++argv; 180 if (!arg) 181 bb_show_usage(); 182 if (arg[0] != '-') 183 goto do_it_now; 184 } 185 186 arg++; /* skip '-' */ 187 188 /* -o PID? (if present, it always is at the end of command line) */ 189 if (is_killall5 && arg[0] == 'o') 190 goto do_it_now; 191 192 /* "--" separates options from args. Testcase: "kill -- -123" */ 193 if (!is_killall5 && arg[0] == '-' && arg[1] == '\0') 194 goto do_it_sooner; 195 196 if (argv[1] && arg[0] == 's' && arg[1] == '\0') { /* -s SIG? */ 197 arg = *++argv; 198 } /* else it must be -SIG */ 199 signo = get_signum(arg); 200 if (signo < 0) { 201 bb_error_msg("bad signal name '%s'", arg); 202 return EXIT_FAILURE; 203 } 204 do_it_sooner: 205 arg = *++argv; 206 207 do_it_now: 208 pid = getpid(); 209 210 if (is_killall5) { 211 pid_t sid; 212 procps_status_t* p = NULL; 213 /* compat: exitcode 2 is "no one was signaled" */ 214 errors = 2; 215 216 /* Find out our session id */ 217 sid = getsid(pid); 218 /* Stop all processes */ 219 if (signo != SIGSTOP && signo != SIGCONT) 220 kill(-1, SIGSTOP); 221 /* Signal all processes except those in our session */ 222 while ((p = procps_scan(p, PSSCAN_PID|PSSCAN_SID)) != NULL) { 223 char **args; 224 225 if (p->sid == (unsigned)sid 226 || p->sid == 0 /* compat: kernel thread, don't signal it */ 227 || p->pid == (unsigned)pid 228 || p->pid == 1 229 ) { 230 continue; 231 } 232 233 /* All remaining args must be -o PID options. 234 * Check p->pid against them. */ 235 args = argv; 236 while (*args) { 237 pid_t omit; 238 239 arg = *args++; 240 if (arg[0] != '-' || arg[1] != 'o') { 241 bb_error_msg("bad option '%s'", arg); 242 errors = 1; 243 goto resume; 244 } 245 arg += 2; 246 if (!arg[0] && *args) 247 arg = *args++; 248 omit = bb_strtoi(arg, NULL, 10); 249 if (errno) { 250 bb_error_msg("invalid number '%s'", arg); 251 errors = 1; 252 goto resume; 253 } 254 if (p->pid == omit) 255 goto dont_kill; 256 } 257 kill(p->pid, signo); 258 errors = 0; 259 dont_kill: ; 260 } 261 resume: 262 /* And let them continue */ 263 if (signo != SIGSTOP && signo != SIGCONT) 264 kill(-1, SIGCONT); 265 return errors; 266 } 267 268#if ENABLE_KILL || ENABLE_KILLALL 269 /* Pid or name is required for kill/killall */ 270 if (!arg) { 271 bb_error_msg("you need to specify whom to kill"); 272 return EXIT_FAILURE; 273 } 274 275 if (!ENABLE_KILL || is_killall) { 276 /* Looks like they want to do a killall. Do that */ 277 do { 278 pid_t* pidList; 279 280 pidList = find_pid_by_name(arg); 281 if (*pidList == 0) { 282 errors++; 283 if (!quiet) 284 bb_error_msg("%s: no process killed", arg); 285 } else { 286 pid_t *pl; 287 288 for (pl = pidList; *pl; pl++) { 289 if (*pl == pid) 290 continue; 291 if (kill(*pl, signo) == 0) 292 continue; 293 errors++; 294 if (!quiet) 295 bb_perror_msg("can't kill pid %d", (int)*pl); 296 } 297 } 298 free(pidList); 299 arg = *++argv; 300 } while (arg); 301 return errors; 302 } 303#endif 304 305#if ENABLE_KILL 306 /* Looks like they want to do a kill. Do that */ 307 while (arg) { 308# if SH_KILL 309 /* 310 * We need to support shell's "hack formats" of 311 * " -PRGP_ID" (yes, with a leading space) 312 * and " PID1 PID2 PID3" (with degenerate case "") 313 */ 314 while (*arg != '\0') { 315 char *end; 316 if (*arg == ' ') 317 arg++; 318 pid = bb_strtoi(arg, &end, 10); 319 if (errno && (errno != EINVAL || *end != ' ')) { 320 bb_error_msg("invalid number '%s'", arg); 321 errors++; 322 break; 323 } 324 if (kill(pid, signo) != 0) { 325 bb_perror_msg("can't kill pid %d", (int)pid); 326 errors++; 327 } 328 arg = end; /* can only point to ' ' or '\0' now */ 329 } 330# else /* ENABLE_KILL but !SH_KILL */ 331 pid = bb_strtoi(arg, NULL, 10); 332 if (errno) { 333 bb_error_msg("invalid number '%s'", arg); 334 errors++; 335 } else if (kill(pid, signo) != 0) { 336 bb_perror_msg("can't kill pid %d", (int)pid); 337 errors++; 338 } 339# endif 340 arg = *++argv; 341 } 342 return errors; 343#endif 344} 345