Fix squid build with glibc 2.17

Building squid failed with a git snapshot of glibc 2.17 on openSUSE
with the following:

pinger.cc: In function 'int main(int, char**)':
pinger.cc:183:21: error: ignoring return value of 'int setgid(__gid_t)', declared with attribute warn_unused_result [-Werror=unused-result]
pinger.cc:184:21: error: ignoring return value of 'int setuid(__uid_t)', declared with attribute warn_unused_result [-Werror=unused-result]
cc1plus: all warnings being treated as errors

And similar with tools.cc.

I've fixed this with the patch below and suggest to apply it,
Andreas

Index: squid-3.2.3/src/icmp/pinger.cc
===================================================================
--- squid-3.2.3.orig/src/icmp/pinger.cc
+++ squid-3.2.3/src/icmp/pinger.cc
@@ -180,8 +180,18 @@ main(int argc, char *argv[])
     }
     max_fd = max(max_fd, squid_link);
 
- setgid(getgid());
- setuid(getuid());
+ if (setgid(getgid()) < 0) {
+ debugs(42, 0, "FATAL: pinger: setgid failed.");
+ icmp4.Close();
+ icmp6.Close();
+ exit (1);
+ }
+ if (setuid(getuid()) < 0) {
+ debugs(42, 0, "FATAL: pinger: setuid failed.");
+ icmp4.Close();
+ icmp6.Close();
+ exit (1);
+ }
 
     last_check_time = squid_curtime;
 
Index: squid-3.2.3/src/tools.cc
===================================================================
--- squid-3.2.3.orig/src/tools.cc
+++ squid-3.2.3/src/tools.cc
@@ -757,7 +757,8 @@ enter_suid(void)
     debugs(21, 3, "enter_suid: PID " << getpid() << " taking root priveleges");
 #if HAVE_SETRESUID
 
- setresuid((uid_t)-1, 0, (uid_t)-1);
+ if (setresuid((uid_t)-1, 0, (uid_t)-1) < 0)
+ debugs (21, 3, "enter_suid: setresuid failed" << xstrerror ());
 #else
 
     setuid(0);
@@ -782,7 +783,8 @@ no_suid(void)
     uid = geteuid();
     debugs(21, 3, "no_suid: PID " << getpid() << " giving up root priveleges forever");
 
- setuid(0);
+ if (setuid(0) < 0)
+ debugs(50, 1, "no_suid: setuid (0): " << xstrerror());
 
     if (setuid(uid) < 0)
         debugs(50, 1, "no_suid: setuid: " << xstrerror());

-- 
 Andreas Jaeger aj@{suse.com,opensuse.org} Twitter/Identica: jaegerandi
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