hush: move msh/lash config into hush.c, no code changes
[oweals/busybox.git] / runit / runsvdir.c
index d37eaf548e37400ff2560ad04a991f18e03a655f..71fde757e0b0f61c7a783e78cea4f2924bd093f0 100644 (file)
@@ -58,9 +58,7 @@ struct globals {
        struct pollfd pfd[1];
        unsigned stamplog;
 #endif
-       smallint need_rescan; /* = 1; */
-       smallint set_pgrp;
-};
+} FIX_ALIASING;
 #define G (*(struct globals*)&bb_common_bufsiz1)
 #define sv          (G.sv          )
 #define svdir       (G.svdir       )
@@ -70,15 +68,12 @@ struct globals {
 #define logpipe     (G.logpipe     )
 #define pfd         (G.pfd         )
 #define stamplog    (G.stamplog    )
-#define need_rescan (G.need_rescan )
-#define set_pgrp    (G.set_pgrp    )
 #define INIT_G() do { \
-       need_rescan = 1; \
 } while (0)
 
 static void fatal2_cannot(const char *m1, const char *m2)
 {
-       bb_perror_msg_and_die("%s: fatal: cannot %s%s", svdir, m1, m2);
+       bb_perror_msg_and_die("%s: fatal: can't %s%s", svdir, m1, m2);
        /* was exiting 100 */
 }
 static void warn3x(const char *m1, const char *m2, const char *m3)
@@ -87,7 +82,7 @@ static void warn3x(const char *m1, const char *m2, const char *m3)
 }
 static void warn2_cannot(const char *m1, const char *m2)
 {
-       warn3x("cannot ", m1, m2);
+       warn3x("can't ", m1, m2);
 }
 #if ENABLE_FEATURE_RUNSVDIR_LOG
 static void warnx(const char *m1)
@@ -96,28 +91,27 @@ static void warnx(const char *m1)
 }
 #endif
 
-static void runsv(int no, const char *name)
+/* inlining + vfork -> bigger code */
+static NOINLINE pid_t runsv(const char *name)
 {
        pid_t pid;
-       char *prog[3];
 
-       prog[0] = (char*)"runsv";
-       prog[1] = (char*)name;
-       prog[2] = NULL;
+       /* If we got signaled, stop spawning children at once! */
+       if (bb_got_signal)
+               return 0;
 
        pid = vfork();
-
        if (pid == -1) {
                warn2_cannot("vfork", "");
-               return;
+               return 0;
        }
        if (pid == 0) {
                /* child */
-               if (set_pgrp)
+               if (option_mask32 & 1) /* -P option? */
                        setsid();
 /* man execv:
- * Signals set to be caught by the calling process image
- * shall be set to the default action in the new process image.
+ * "Signals set to be caught by the calling process image
+ *  shall be set to the default action in the new process image."
  * Therefore, we do not need this: */
 #if 0
                bb_signals(0
@@ -125,23 +119,25 @@ static void runsv(int no, const char *name)
                        | (1 << SIGTERM)
                        , SIG_DFL);
 #endif
-               execvp(prog[0], prog);
+               execlp("runsv", "runsv", name, (char *) NULL);
                fatal2_cannot("start runsv ", name);
        }
-       sv[no].pid = pid;
+       return pid;
 }
 
-static void do_rescan(void)
+/* gcc 4.3.0 does better with NOINLINE */
+static NOINLINE int do_rescan(void)
 {
        DIR *dir;
-       direntry *d;
+       struct dirent *d;
        int i;
        struct stat s;
+       int need_rescan = 0;
 
        dir = opendir(".");
        if (!dir) {
                warn2_cannot("open directory ", svdir);
-               return;
+               return 1; /* need to rescan again soon */
        }
        for (i = 0; i < svnum; i++)
                sv[i].isgone = 1;
@@ -159,47 +155,47 @@ static void do_rescan(void)
                }
                if (!S_ISDIR(s.st_mode))
                        continue;
+               /* Do we have this service listed already? */
                for (i = 0; i < svnum; i++) {
                        if ((sv[i].ino == s.st_ino)
 #if CHECK_DEVNO_TOO
                         && (sv[i].dev == s.st_dev)
 #endif
                        ) {
-                               sv[i].isgone = 0;
-                               if (!sv[i].pid)
-                                       runsv(i, d->d_name);
-                               break;
+                               if (sv[i].pid == 0) /* restart if it has died */
+                                       goto run_ith_sv;
+                               sv[i].isgone = 0; /* "we still see you" */
+                               goto next_dentry;
                        }
                }
-               if (i == svnum) {
-                       /* new service */
+               { /* Not found, make new service */
                        struct service *svnew = realloc(sv, (i+1) * sizeof(*sv));
                        if (!svnew) {
                                warn2_cannot("start runsv ", d->d_name);
+                               need_rescan = 1;
                                continue;
                        }
                        sv = svnew;
                        svnum++;
-                       memset(&sv[i], 0, sizeof(sv[i]));
-                       sv[i].ino = s.st_ino;
 #if CHECK_DEVNO_TOO
                        sv[i].dev = s.st_dev;
 #endif
-                       /*sv[i].pid = 0;*/
-                       /*sv[i].isgone = 0;*/
-                       runsv(i, d->d_name);
-                       need_rescan = 1;
+                       sv[i].ino = s.st_ino;
+ run_ith_sv:
+                       sv[i].pid = runsv(d->d_name);
+                       sv[i].isgone = 0;
                }
+ next_dentry: ;
        }
        i = errno;
        closedir(dir);
-       if (i) {
+       if (i) { /* readdir failed */
                warn2_cannot("read directory ", svdir);
-               need_rescan = 1;
-               return;
+               return 1; /* need to rescan again soon */
        }
 
-       /* Send SIGTERM to runsv whose directories were not found (removed) */
+       /* Send SIGTERM to runsv whose directories
+        * were no longer found (-> must have been removed) */
        for (i = 0; i < svnum; i++) {
                if (!sv[i].isgone)
                        continue;
@@ -208,8 +204,8 @@ static void do_rescan(void)
                svnum--;
                sv[i] = sv[svnum];
                i--; /* so that we don't skip new sv[i] (bug was here!) */
-               need_rescan = 1;
        }
+       return need_rescan;
 }
 
 int runsvdir_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
@@ -221,16 +217,20 @@ int runsvdir_main(int argc UNUSED_PARAM, char **argv)
        time_t last_mtime = 0;
        int wstat;
        int curdir;
-       int pid;
+       pid_t pid;
        unsigned deadline;
        unsigned now;
        unsigned stampcheck;
        int i;
+       int need_rescan = 1;
+       char *opt_s_argv[3];
 
        INIT_G();
 
        opt_complementary = "-1";
-       set_pgrp = getopt32(argv, "P");
+       opt_s_argv[0] = NULL;
+       opt_s_argv[2] = NULL;
+       getopt32(argv, "Ps:", &opt_s_argv[0]);
        argv += optind;
 
        bb_signals(0
@@ -256,14 +256,14 @@ int runsvdir_main(int argc UNUSED_PARAM, char **argv)
                if (rploglen < 7) {
                        warnx("log must have at least seven characters");
                } else if (piped_pair(logpipe)) {
-                       warnx("cannot create pipe for log");
+                       warnx("can't create pipe for log");
                } else {
                        close_on_exec_on(logpipe.rd);
                        close_on_exec_on(logpipe.wr);
                        ndelay_on(logpipe.rd);
                        ndelay_on(logpipe.wr);
                        if (dup2(logpipe.wr, 2) == -1) {
-                               warnx("cannot set filedescriptor for log");
+                               warnx("can't set filedescriptor for log");
                        } else {
                                pfd[0].fd = logpipe.rd;
                                pfd[0].events = POLLIN;
@@ -291,10 +291,9 @@ int runsvdir_main(int argc UNUSED_PARAM, char **argv)
                                break;
                        for (i = 0; i < svnum; i++) {
                                if (pid == sv[i].pid) {
-                                       /* runsv has gone */
+                                       /* runsv has died */
                                        sv[i].pid = 0;
                                        need_rescan = 1;
-                                       break;
                                }
                        }
                }
@@ -313,19 +312,20 @@ int runsvdir_main(int argc UNUSED_PARAM, char **argv)
                                                last_mtime = s.st_mtime;
                                                last_dev = s.st_dev;
                                                last_ino = s.st_ino;
-                                               need_rescan = 0;
                                                //if (now <= mtime)
                                                //      sleep(1);
-                                               do_rescan();
+                                               need_rescan = do_rescan();
                                                while (fchdir(curdir) == -1) {
                                                        warn2_cannot("change directory, pausing", "");
                                                        sleep(5);
                                                }
-                                       } else
+                                       } else {
                                                warn2_cannot("change directory to ", svdir);
+                                       }
                                }
-                       } else
+                       } else {
                                warn2_cannot("stat ", svdir);
+                       }
                }
 
 #if ENABLE_FEATURE_RUNSVDIR_LOG
@@ -338,7 +338,6 @@ int runsvdir_main(int argc UNUSED_PARAM, char **argv)
                pfd[0].revents = 0;
 #endif
                deadline = (need_rescan ? 1 : 5);
- do_sleep:
                sig_block(SIGCHLD);
 #if ENABLE_FEATURE_RUNSVDIR_LOG
                if (rplog)
@@ -360,24 +359,35 @@ int runsvdir_main(int argc UNUSED_PARAM, char **argv)
                        }
                }
 #endif
-               switch (bb_got_signal) {
-               case SIGHUP:
+               if (!bb_got_signal)
+                       continue;
+
+               /* -s SCRIPT: useful if we are init.
+                * In this case typically script never returns,
+                * it halts/powers off/reboots the system. */
+               if (opt_s_argv[0]) {
+                       /* Single parameter: signal# */
+                       opt_s_argv[1] = utoa(bb_got_signal);
+                       pid = spawn(opt_s_argv);
+                       if (pid > 0) {
+                               /* Remembering to wait for _any_ children,
+                                * not just pid */
+                               while (wait(NULL) != pid)
+                                       continue;
+                       }
+               }
+
+               if (bb_got_signal == SIGHUP) {
                        for (i = 0; i < svnum; i++)
                                if (sv[i].pid)
                                        kill(sv[i].pid, SIGTERM);
-                       /* fall through */
-               case SIGTERM:
-                       /* exit, unless we are init */
-                       if (getpid() != 1)
-                               goto ret;
-               default:
-                       /* so we are init. do not exit,
-                        * and pause respawning - we may be rebooting... */
-                       bb_got_signal = 0;
-                       deadline = 60;
-                       goto do_sleep;
                }
-       }
- ret:
-       return (SIGHUP == bb_got_signal) ? 111 : EXIT_SUCCESS;
+               /* SIGHUP or SIGTERM (or SIGUSRn if we are init) */
+               /* Exit unless we are init */
+               if (getpid() != 1)
+                       return (SIGHUP == bb_got_signal) ? 111 : EXIT_SUCCESS;
+
+               /* init continues to monitor services forever */
+               bb_got_signal = 0;
+       } /* for (;;) */
 }