From 6e229d7655b00065cfdb0e79059f6bb014530ee7 Mon Sep 17 00:00:00 2001
From: Martin Mares <mj@ucw.cz>
Date: Wed, 18 Jul 2012 14:23:52 +0200
Subject: [PATCH] Daemon: Added DAEMON_FLAG_SIMULATE

---
 ucw/daemon.c | 12 ++++++++++++
 ucw/daemon.h |  4 ++++
 2 files changed, 16 insertions(+)

diff --git a/ucw/daemon.c b/ucw/daemon.c
index 00313b94..ec9a2187 100644
--- a/ucw/daemon.c
+++ b/ucw/daemon.c
@@ -82,6 +82,9 @@ daemon_init(struct daemon_params *dp)
 {
   daemon_resolve_ugid(dp);
 
+  if (dp->flags & DAEMON_FLAG_SIMULATE)
+    return;
+
   if (dp->pid_file)
     {
       // Check that PID file path is absolute
@@ -115,6 +118,12 @@ daemon_init(struct daemon_params *dp)
 void
 daemon_run(struct daemon_params *dp, void (*body)(struct daemon_params *dp))
 {
+  if (dp->flags & DAEMON_FLAG_SIMULATE)
+    {
+      body(dp);
+      return;
+    }
+
   // Switch GID and UID
   if (dp->want_setgid && setresgid(dp->run_as_gid, dp->run_as_gid, dp->run_as_gid) < 0)
     die("Cannot set GID to %d: %m", (int) dp->run_as_gid);
@@ -168,6 +177,9 @@ daemon_run(struct daemon_params *dp, void (*body)(struct daemon_params *dp))
 void
 daemon_exit(struct daemon_params *dp)
 {
+  if (dp->flags & DAEMON_FLAG_SIMULATE)
+    return;
+
   if (dp->pid_file)
     {
       if (unlink(dp->pid_file) < 0)
diff --git a/ucw/daemon.h b/ucw/daemon.h
index 9cdfe050..c5beacc0 100644
--- a/ucw/daemon.h
+++ b/ucw/daemon.h
@@ -30,6 +30,7 @@ struct daemon_params {
 /** Flags passed to the daemon helper. **/
 enum daemon_flags {
   DAEMON_FLAG_PRESERVE_CWD = 1,		// Skip chdir("/")
+  DAEMON_FLAG_SIMULATE = 2,		// Simulate daemonization (avoid fork etc.)
 };
 
 /**
@@ -44,6 +45,9 @@ void daemon_init(struct daemon_params *dp);
  * a new process and does all necessary setup. Inside the new process, it calls
  * @body (and when it returns, it exits the process). In the original process, it writes
  * the PID file and returns.
+ *
+ * When `DAEMON_FLAG_SIMULATE` is set, it justs calls @body. This is useful
+ * for running of daemons in a debugger.
  **/
 void daemon_run(struct daemon_params *dp, void (*body)(struct daemon_params *dp));
 
-- 
2.39.5