Sort more misplaced applets into coreutils or util-linux
[oweals/busybox.git] / debianutils / start_stop_daemon.c
index 568f32eec15a3468ac6a07f5abb3a3ce1d13ca2e..4a9e0653e29a8da9a5a9c519fccab74e654490ae 100644 (file)
@@ -5,7 +5,7 @@
  * Written by Marek Michalkiewicz <marekm@i17linuxb.ists.pwr.wroc.pl>,
  * Adapted for busybox David Kimdon <dwhedon@gordian.com>
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
 /*
@@ -31,7 +31,8 @@ Options controlling process matching
 [TODO: can PROCESS_NAME be a full pathname? Should we require full match then
 with /proc/$PID/exe or argv[0] (comm can't be matched, it never contains path)]
         -x,--exec EXECUTABLE    Look for processes that were started with this
-                                command in /proc/$PID/cmdline.
+                                command in /proc/$PID/exe and /proc/$PID/cmdline
+                                (/proc/$PID/cmdline is a bbox extension)
                                 Unlike -n, we match against the full path:
                                 "ntpd" != "./ntpd" != "/path/to/ntpd"
         -p,--pidfile PID_FILE   Look for processes with PID from this file
@@ -55,12 +56,101 @@ Misc options:
         -q,--quiet              Quiet
         -v,--verbose            Verbose
 */
+//config:config START_STOP_DAEMON
+//config:      bool "start-stop-daemon"
+//config:      default y
+//config:      help
+//config:        start-stop-daemon is used to control the creation and
+//config:        termination of system-level processes, usually the ones
+//config:        started during the startup of the system.
+//config:
+//config:config FEATURE_START_STOP_DAEMON_LONG_OPTIONS
+//config:      bool "Enable long options"
+//config:      default y
+//config:      depends on START_STOP_DAEMON && LONG_OPTS
+//config:
+//config:config FEATURE_START_STOP_DAEMON_FANCY
+//config:      bool "Support additional arguments"
+//config:      default y
+//config:      depends on START_STOP_DAEMON
+//config:      help
+//config:        -o|--oknodo ignored since we exit with 0 anyway
+//config:        -v|--verbose
+//config:        -N|--nicelevel N
+
+//applet:IF_START_STOP_DAEMON(APPLET_ODDNAME(start-stop-daemon, start_stop_daemon, BB_DIR_SBIN, BB_SUID_DROP, start_stop_daemon))
+
+//kbuild:lib-$(CONFIG_START_STOP_DAEMON) += start_stop_daemon.o
+
+//usage:#define start_stop_daemon_trivial_usage
+//usage:       "[OPTIONS] [-S|-K] ... [-- ARGS...]"
+//usage:#define start_stop_daemon_full_usage "\n\n"
+//usage:       "Search for matching processes, and then\n"
+//usage:       "-K: stop all matching processes.\n"
+//usage:       "-S: start a process unless a matching process is found.\n"
+//usage:       IF_FEATURE_START_STOP_DAEMON_LONG_OPTIONS(
+//usage:     "\nProcess matching:"
+//usage:     "\n       -u,--user USERNAME|UID  Match only this user's processes"
+//usage:     "\n       -n,--name NAME          Match processes with NAME"
+//usage:     "\n                               in comm field in /proc/PID/stat"
+//usage:     "\n       -x,--exec EXECUTABLE    Match processes with this command"
+//usage:     "\n                               in /proc/PID/{exe,cmdline}"
+//usage:     "\n       -p,--pidfile FILE       Match a process with PID from the file"
+//usage:     "\n       All specified conditions must match"
+//usage:     "\n-S only:"
+//usage:     "\n       -x,--exec EXECUTABLE    Program to run"
+//usage:     "\n       -a,--startas NAME       Zeroth argument"
+//usage:     "\n       -b,--background         Background"
+//usage:       IF_FEATURE_START_STOP_DAEMON_FANCY(
+//usage:     "\n       -N,--nicelevel N        Change nice level"
+//usage:       )
+//usage:     "\n       -c,--chuid USER[:[GRP]] Change to user/group"
+//usage:     "\n       -m,--make-pidfile       Write PID to the pidfile specified by -p"
+//usage:     "\n-K only:"
+//usage:     "\n       -s,--signal SIG         Signal to send"
+//usage:     "\n       -t,--test               Match only, exit with 0 if a process is found"
+//usage:     "\nOther:"
+//usage:       IF_FEATURE_START_STOP_DAEMON_FANCY(
+//usage:     "\n       -o,--oknodo             Exit with status 0 if nothing is done"
+//usage:     "\n       -v,--verbose            Verbose"
+//usage:       )
+//usage:     "\n       -q,--quiet              Quiet"
+//usage:       )
+//usage:       IF_NOT_FEATURE_START_STOP_DAEMON_LONG_OPTIONS(
+//usage:     "\nProcess matching:"
+//usage:     "\n       -u USERNAME|UID Match only this user's processes"
+//usage:     "\n       -n NAME         Match processes with NAME"
+//usage:     "\n                       in comm field in /proc/PID/stat"
+//usage:     "\n       -x EXECUTABLE   Match processes with this command"
+//usage:     "\n                       command in /proc/PID/cmdline"
+//usage:     "\n       -p FILE         Match a process with PID from the file"
+//usage:     "\n       All specified conditions must match"
+//usage:     "\n-S only:"
+//usage:     "\n       -x EXECUTABLE   Program to run"
+//usage:     "\n       -a NAME         Zeroth argument"
+//usage:     "\n       -b              Background"
+//usage:       IF_FEATURE_START_STOP_DAEMON_FANCY(
+//usage:     "\n       -N N            Change nice level"
+//usage:       )
+//usage:     "\n       -c USER[:[GRP]] Change to user/group"
+//usage:     "\n       -m              Write PID to the pidfile specified by -p"
+//usage:     "\n-K only:"
+//usage:     "\n       -s SIG          Signal to send"
+//usage:     "\n       -t              Match only, exit with 0 if a process is found"
+//usage:     "\nOther:"
+//usage:       IF_FEATURE_START_STOP_DAEMON_FANCY(
+//usage:     "\n       -o              Exit with status 0 if nothing is done"
+//usage:     "\n       -v              Verbose"
+//usage:       )
+//usage:     "\n       -q              Quiet"
+//usage:       )
 
 #include <sys/resource.h>
 
 /* Override ENABLE_FEATURE_PIDFILE */
 #define WANT_PIDFILE 1
 #include "libbb.h"
+#include "common_bufsiz.h"
 
 struct pid_list {
        struct pid_list *next;
@@ -99,7 +189,7 @@ struct globals {
        int user_id;
        smallint signal_nr;
 } FIX_ALIASING;
-#define G (*(struct globals*)&bb_common_bufsiz1)
+#define G (*(struct globals*)bb_common_bufsiz1)
 #define userspec          (G.userspec            )
 #define cmdname           (G.cmdname             )
 #define execname          (G.execname            )
@@ -107,6 +197,7 @@ struct globals {
 #define user_id           (G.user_id             )
 #define signal_nr         (G.signal_nr           )
 #define INIT_G() do { \
+       setup_common_bufsiz(); \
        user_id = -1; \
        signal_nr = 15; \
 } while (0)
@@ -135,8 +226,18 @@ static int pid_is_exec(pid_t pid)
 {
        ssize_t bytes;
        char buf[sizeof("/proc/%u/cmdline") + sizeof(int)*3];
+       char *procname, *exelink;
+       int match;
 
-       sprintf(buf, "/proc/%u/cmdline", (unsigned)pid);
+       procname = buf + sprintf(buf, "/proc/%u/exe", (unsigned)pid) - 3;
+
+       exelink = xmalloc_readlink(buf);
+       match = (exelink && strcmp(execname, exelink) == 0);
+       free(exelink);
+       if (match)
+               return match;
+
+       strcpy(procname, "cmdline");
        bytes = open_read_close(buf, G.execname_cmpbuf, G.execname_sizeof);
        if (bytes > 0) {
                G.execname_cmpbuf[bytes] = '\0';
@@ -274,11 +375,17 @@ static int do_stop(void)
                goto ret;
        }
        for (p = G.found_procs; p; p = p->next) {
-               if (TEST || kill(p->pid, signal_nr) == 0) {
+               if (kill(p->pid, TEST ? 0 : signal_nr) == 0) {
                        killed++;
                } else {
-                       p->pid = 0;
                        bb_perror_msg("warning: killing process %u", (unsigned)p->pid);
+                       p->pid = 0;
+                       if (TEST) {
+                               /* Example: -K --test --pidfile PIDFILE detected
+                                * that PIDFILE's pid doesn't exist */
+                               killed = -1;
+                               goto ret;
+                       }
                }
        }
        if (!QUIET && killed) {
@@ -405,7 +512,7 @@ int start_stop_daemon_main(int argc UNUSED_PARAM, char **argv)
        *--argv = startas;
        if (opt & OPT_BACKGROUND) {
 #if BB_MMU
-               bb_daemonize(DAEMON_DEVNULL_STDIO + DAEMON_CLOSE_EXTRA_FDS);
+               bb_daemonize(DAEMON_DEVNULL_STDIO + DAEMON_CLOSE_EXTRA_FDS + DAEMON_DOUBLE_FORK);
                /* DAEMON_DEVNULL_STDIO is superfluous -
                 * it's always done by bb_daemonize() */
 #else
@@ -431,10 +538,18 @@ int start_stop_daemon_main(int argc UNUSED_PARAM, char **argv)
                write_pidfile(pidfile);
        }
        if (opt & OPT_c) {
-               struct bb_uidgid_t ugid = { -1, -1 };
+               struct bb_uidgid_t ugid;
                parse_chown_usergroup_or_die(&ugid, chuid);
-               if (ugid.gid != (gid_t) -1) xsetgid(ugid.gid);
-               if (ugid.uid != (uid_t) -1) xsetuid(ugid.uid);
+               if (ugid.uid != (uid_t) -1L) {
+                       struct passwd *pw = xgetpwuid(ugid.uid);
+                       if (ugid.gid != (gid_t) -1L)
+                               pw->pw_gid = ugid.gid;
+                       /* initgroups, setgid, setuid: */
+                       change_identity(pw);
+               } else if (ugid.gid != (gid_t) -1L) {
+                       xsetgid(ugid.gid);
+                       setgroups(1, &ugid.gid);
+               }
        }
 #if ENABLE_FEATURE_START_STOP_DAEMON_FANCY
        if (opt & OPT_NICELEVEL) {