X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=lib%2Fdaemon.c;h=a2eff07c038c0c3c53ccbbce57de9d2086ae2a85;hb=8aee05ccf4818ea3a070163f7d3dc43126d8443e;hp=c4a82647f8ace909101e36d89409a024cce9b70d;hpb=e0edde6fee279cdbbf3c179f5f50adaf0c7c7f1e;p=openvswitch

diff --git a/lib/daemon.c b/lib/daemon.c
index c4a82647..a2eff07c 100644
--- a/lib/daemon.c
+++ b/lib/daemon.c
@@ -245,6 +245,43 @@ daemonize(void)
     daemonize_complete();
 }
 
+/* Calls fork() and on success returns its return value.  On failure, logs an
+ * error and exits unsuccessfully.
+ *
+ * Post-fork, but before returning, this function calls a few other functions
+ * that are generally useful if the child isn't planning to exec a new
+ * process. */
+pid_t
+fork_and_clean_up(void)
+{
+    pid_t pid;
+
+    pid = fork();
+    if (pid > 0) {
+        /* Running in parent process. */
+        fatal_signal_fork();
+    } else if (!pid) {
+        /* Running in child process. */
+        time_postfork();
+        lockfile_postfork();
+    } else {
+        VLOG_FATAL("fork failed (%s)", strerror(errno));
+    }
+
+    return pid;
+}
+
+/* Forks, then:
+ *
+ *   - In the parent, waits for the child to signal that it has completed its
+ *     startup sequence.  Then stores -1 in '*fdp' and returns the child's pid.
+ *
+ *   - In the child, stores a fd in '*fdp' and returns 0.  The caller should
+ *     pass the fd to fork_notify_startup() after it finishes its startup
+ *     sequence.
+ *
+ * If something goes wrong with the fork, logs a critical error and aborts the
+ * process. */
 static pid_t
 fork_and_wait_for_startup(int *fdp)
 {
@@ -253,14 +290,13 @@ fork_and_wait_for_startup(int *fdp)
 
     xpipe(fds);
 
-    pid = fork();
+    pid = fork_and_clean_up();
     if (pid > 0) {
         /* Running in parent process. */
         size_t bytes_read;
         char c;
 
         close(fds[1]);
-        fatal_signal_fork();
         if (read_fully(fds[0], &c, 1, &bytes_read) != 0) {
             int retval;
             int status;
@@ -290,11 +326,7 @@ fork_and_wait_for_startup(int *fdp)
     } else if (!pid) {
         /* Running in child process. */
         close(fds[0]);
-        time_postfork();
-        lockfile_postfork();
         *fdp = fds[1];
-    } else {
-        VLOG_FATAL("fork failed (%s)", strerror(errno));
     }
 
     return pid;
@@ -340,13 +372,11 @@ static void
 monitor_daemon(pid_t daemon_pid)
 {
     /* XXX Should log daemon's stderr output at startup time. */
-    const char *saved_program_name;
     time_t last_restart;
     char *status_msg;
     int crashes;
 
-    saved_program_name = program_name;
-    program_name = xasprintf("monitor(%s)", program_name);
+    subprogram_name = "monitor";
     status_msg = xstrdup("healthy");
     last_restart = TIME_MIN;
     crashes = 0;
@@ -355,7 +385,7 @@ monitor_daemon(pid_t daemon_pid)
         int status;
 
         proctitle_set("%s: monitoring pid %lu (%s)",
-                      saved_program_name, (unsigned long int) daemon_pid,
+                      program_name, (unsigned long int) daemon_pid,
                       status_msg);
 
         do {
@@ -417,8 +447,7 @@ monitor_daemon(pid_t daemon_pid)
 
     /* Running in new daemon process. */
     proctitle_restore();
-    free((char *) program_name);
-    program_name = saved_program_name;
+    subprogram_name = "";
 }
 
 /* Close standard file descriptors (except any that the client has requested we