From 92ec05ab67c461a0aaa189292166e094eb37ce41 Mon Sep 17 00:00:00 2001
From: Laurence Withers <lwithers@amethyst.lwithers.me.uk>
Date: Sat, 26 Jul 2008 20:47:49 +0000
Subject: [PATCH] Save and restore errno before using %m specifier

---
 src/daemonitor/200_log.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/daemonitor/200_log.c b/src/daemonitor/200_log.c
index cfcf5a0..2a5c545 100644
--- a/src/daemonitor/200_log.c
+++ b/src/daemonitor/200_log.c
@@ -111,11 +111,14 @@ int log_func_fd;
 void log_func_file(int level, const char* fmt, ...)
 {
     va_list va;
-    int ret;
+    int ret, saved_errno;
     const char* level_str;
     char timebuf[40];
     time_t t;
 
+    /* save errno, because dprintf will clobber it */
+    saved_errno = errno;
+
     /* choose appropriate line description */
     switch(level) {
     case LOG_EMERG:     level_str = "EMERG"; break;
@@ -136,6 +139,7 @@ void log_func_file(int level, const char* fmt, ...)
     /* print to file descriptor */
     va_start(va, fmt);
     ret = dprintf(log_func_fd, "%s %s ", timebuf, level_str);
+    errno = saved_errno;
     if(ret != -1) ret = vdprintf(log_func_fd, fmt, va);
     if(ret != -1 && safe_write_fixed(log_func_fd, "\n", 1) != 1) ret = -1;
     va_end(va);