From: Martin Mares <mj@ucw.cz>
Date: Tue, 17 Jul 2012 20:50:50 +0000 (+0200)
Subject: Daemon: Reverted to one-level locking and added bits of docs
X-Git-Tag: v5.99~155
X-Git-Url: http://mj.ucw.cz/gitweb/?a=commitdiff_plain;h=7c6ad545b6423bab37bbb8658db9e35964cc9537;p=libucw.git

Daemon: Reverted to one-level locking and added bits of docs
---

diff --git a/ucw/daemon.c b/ucw/daemon.c
index 04060afd..0012db46 100644
--- a/ucw/daemon.c
+++ b/ucw/daemon.c
@@ -148,7 +148,7 @@ void daemon_run(struct daemon_params *dp, void (*body)(struct daemon_params *dp)
       exit(0);
     }
 
-  // Write PID and downgrade the lock to shared
+  // Write PID
   if (dp->pid_file)
     {
       char buf[32];
@@ -156,11 +156,9 @@ void daemon_run(struct daemon_params *dp, void (*body)(struct daemon_params *dp)
       ASSERT(c <= (int) sizeof(buf));
       if (lseek(dp->pid_fd, 0, SEEK_SET) < 0 ||
 	  write(dp->pid_fd, buf, c) != c ||
-	  ftruncate(dp->pid_fd, c))
+	  ftruncate(dp->pid_fd, c) ||
+	  close(dp->pid_fd) < 0)
 	die("Cannot write PID to `%s': %m", dp->pid_file);
-      if (flock(dp->pid_fd, LOCK_SH | LOCK_NB) < 0)
-	die("Cannot re-lock `%s': %m", dp->pid_file);
-      close(dp->pid_fd);
     }
 }
 
diff --git a/ucw/daemon.h b/ucw/daemon.h
index c00f00d1..0cf87086 100644
--- a/ucw/daemon.h
+++ b/ucw/daemon.h
@@ -12,6 +12,7 @@
 
 #include <sys/types.h>
 
+/** Parameters passed to the daemon helper. **/
 struct daemon_params {
   uns flags;				// DAEMON_FLAG_xxx
   const char *pid_file;			// A path to PID file (optional)
@@ -26,6 +27,7 @@ struct daemon_params {
   int pid_fd;
 };
 
+/** Flags passed to the daemon helper. **/
 enum daemon_flags {
   DAEMON_FLAG_PRESERVE_CWD = 1,		// Skip chdir("/")
 };