server/: Make initialization errors be non-fatal and restartable.

[tripe] / server / admin.c

diff --git a/server/admin.c b/server/admin.c
index 78188f54ca16cfa65b50e3947df4779c67c87abf..ad44132f0e6a6a500e5d1e82ca9965d6dba64ac6 100644 (file)
--- a/server/admin.c
+++ b/server/admin.c
@@ -2470,12 +2470,12 @@ void a_daemon(void) { flags |= F_DAEMON; }
  *             @gid_t g@ = group to own the socket
  *             @mode_t m@ = permissions to set on the socket
  *
- * Returns:    ---
+ * Returns:    Zero on success, @-1@ on failure.
  *
  * Use:                Creates the admin listening socket.
  */
 
-void a_listen(const char *name, uid_t u, gid_t g, mode_t m)
+int a_listen(const char *name, uid_t u, gid_t g, mode_t m)
 {
   int fd;
   int n = 5;
@@ -2488,7 +2488,7 @@ void a_listen(const char *name, uid_t u, gid_t g, mode_t m)
   sz = strlen(name) + 1;
   if (sz > sizeof(sun.sun_path)) {
     a_warn("ADMIN", "admin-socket", "%s", name, "name-too-long", A_END);
-    exit(EXIT_FAILURE);
+    goto fail_0;
   }
   BURN(sun);
   sun.sun_family = AF_UNIX;
@@ -2502,7 +2502,7 @@ again:
   if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
     a_warn("ADMIN", "admin-socket", "%s", sun.sun_path,
           "create-failed", "?ERRNO", A_END);
-    exit(EXIT_FAILURE);
+    goto fail_1;
   }
   if (bind(fd, (struct sockaddr *)&sun, sz) < 0) {
     struct stat st;
@@ -2510,34 +2510,34 @@ again:
     if (errno != EADDRINUSE) {
       a_warn("ADMIN", "admin-socket", "%s", sun.sun_path,
             "bind-failed", "?ERRNO", A_END);
-      exit(EXIT_FAILURE);
+      goto fail_2;
     }
     if (!n) {
       a_warn("ADMIN", "admin-socket", "%s", sun.sun_path,
             "too-many-retries", A_END);
-      exit(EXIT_FAILURE);
+      goto fail_2;
     }
     n--;
     if (!connect(fd, (struct sockaddr *)&sun, sz)) {
       a_warn("ADMIN", "admin-socket", "%s", sun.sun_path,
             "already-in-use", A_END);
-      exit(EXIT_FAILURE);
+      goto fail_2;
     }
     if (errno != ECONNREFUSED) {
       a_warn("ADMIN", "admin-socket", "%s", sun.sun_path,
             "bind-failed", "?ERR", e, A_END);
-      exit(EXIT_FAILURE);
+      goto fail_2;
     }
     if (stat(sun.sun_path, &st)) {
       if (errno == ENOENT) { close(fd); goto again; }
       a_warn("ADMIN", "admin-socket", "%s", sun.sun_path,
             "stat-failed", "?ERRNO", A_END);
-      exit(EXIT_FAILURE);
+      goto fail_2;
     }
     if (!S_ISSOCK(st.st_mode)) {
       a_warn("ADMIN", "admin-socket", "%s", sun.sun_path,
             "not-a-socket", A_END);
-      exit(EXIT_FAILURE);
+      goto fail_2;
     }
     T( trace(T_ADMIN, "admin: stale socket found; removing it"); )
     unlink(sun.sun_path);
@@ -2547,26 +2547,39 @@ again:
   if (chown(sun.sun_path, u, g)) {
     a_warn("ADMIN", "admin-socket", "%s", sun.sun_path,
           "chown-failed", "?ERRNO", A_END);
-    exit(EXIT_FAILURE);
+    goto fail_3;
   }
   if (chmod(sun.sun_path, m)) {
     a_warn("ADMIN", "admin-socket", "%s", sun.sun_path,
           "chmod-failed", "?ERRNO", A_END);
-    exit(EXIT_FAILURE);
+    goto fail_3;
   }
-  umask(omask);
   fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
   if (listen(fd, 5)) {
     a_warn("ADMIN", "admin-socket", "%s", sun.sun_path,
           "listen-failed", "?ERRNO", A_END);
-    exit(EXIT_FAILURE);
+    goto fail_3;
   }
+  umask(omask);
 
   /* --- Listen to the socket --- */
 
   sel_initfile(&sel, &sock, fd, SEL_READ, a_accept, 0);
   sel_addfile(&sock);
   sockname = name;
+
+  return (0);
+
+  /* --- Clean up if things go sideways --- */
+
+fail_3:
+  unlink(sun.sun_path);
+fail_2:
+  close(fd);
+fail_1:
+  umask(omask);
+fail_0:
+  return (-1);
 }
 
 /* --- @a_unlisten@ --- *
@@ -2633,21 +2646,17 @@ void a_signals(void)
  *
  * Arguments:  ---
  *
- * Returns:    ---
+ * Returns:    Zero on success, @-1@ on failure.
  *
  * Use:                Creates the admin listening socket.
  */
 
-void a_init(void)
+int a_init(void)
 {
 #ifdef HAVE_LIBADNS
   int err;
 #endif
 
-  /* --- Create services table --- */
-
-  sym_create(&a_svcs);
-
   /* --- Prepare the background name resolver --- */
 
 #ifdef HAVE_LIBADNS
@@ -2657,12 +2666,20 @@ void a_init(void)
                        adns_if_noautosys),
                       0)) != 0) {
     a_warn("ADMIN", "adns-init-failed", "?ERRNO", A_END);
-    exit(EXIT_FAILURE);
+    return (-1);
   }
   sel_addhook(&sel, &hook, before_select, after_select, 0);
 #else
   bres_init(&sel);
 #endif
+
+  /* --- Create services table --- */
+
+  sym_create(&a_svcs);
+
+  /* --- All done --- */
+
+  return (0);
 }
 
 /*----- That's all, folks -------------------------------------------------*/