Save and restore errno from within signal handlers.

This is recommended by the POSIX standard, as well as by the sigaction(2) manpage
for various platforms that we support (e.g. Mac OS X).

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.8@324955 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/main/asterisk.c b/main/asterisk.c
index beba0679c5515b2efc90ec11002ef0546daa2768..5609fb99f9df09c65789bef8a5565d286add1da6 100644 (file)
--- a/main/asterisk.c
+++ b/main/asterisk.c
@@ -1479,7 +1479,7 @@ static struct sigaction urg_handler = {
 
 static void _hup_handler(int num)
 {
-       int a = 0;
+       int a = 0, save_errno = errno;
        if (option_verbose > 1) 
                printf("Received HUP signal -- Reloading configs\n");
        if (restartnow)
@@ -1490,6 +1490,7 @@ static void _hup_handler(int num)
                        fprintf(stderr, "hup_handler: write() failed: %s\n", strerror(errno));
                }
        }
+       errno = save_errno;
 }
 
 static struct sigaction hup_handler = {
@@ -1500,7 +1501,7 @@ static struct sigaction hup_handler = {
 static void _child_handler(int sig)
 {
        /* Must not ever ast_log or ast_verbose within signal handler */
-       int n, status;
+       int n, status, save_errno = errno;
 
        /*
         * Reap all dead children -- not just one
@@ -1509,6 +1510,7 @@ static void _child_handler(int sig)
                ;
        if (n == 0 && option_debug)     
                printf("Huh?  Child handler, but nobody there?\n");
+       errno = save_errno;
 }
 
 static struct sigaction child_handler = {