Don't let check_disk hang on hanging file systems

configure.ac

@@ -560,6 +560,18 @@ else
 	with_gnutls="no"
 fi
 
+dnl Check for POSIX thread libraries
+AC_CHECK_HEADERS(pthread.h)
+case $host in
+	*sun* | *solaris*)
+		AC_CHECK_LIB(pthread,pthread_create,THRLIBS="-lpthread -lrt")
+	;;
+	*)
+		AC_CHECK_LIB(pthread,pthread_create,THRLIBS="-lpthread")
+	;;
+esac
+AC_SUBST(THRLIBS)
+
 dnl
 dnl Checks for header files.
 dnl

plugins/Makefile.am

@@ -71,7 +71,7 @@ check_apt_LDADD = $(BASEOBJS)
 check_cluster_LDADD = $(BASEOBJS)
 check_dbi_LDADD = $(NETLIBS) $(DBILIBS)
 check_dig_LDADD = $(NETLIBS) $(MATHLIBS)
-check_disk_LDADD = $(BASEOBJS)
+check_disk_LDADD = $(BASEOBJS) $(THRLIBS)
 check_dns_LDADD = $(NETLIBS)
 check_dummy_LDADD = $(BASEOBJS)
 check_fping_LDADD = $(NETLIBS)

plugins/check_disk.c

@@ -51,6 +51,9 @@ const char *email = "devel@nagios-plugins.org";
 # include <limits.h>
 #endif
 #include "regex.h"
+#if HAVE_PTHREAD_H
+# include <pthread.h>
+#endif
 
 #ifdef __CYGWIN__
 # include <windows.h>
@@ -130,6 +133,7 @@ void print_help (void);
 void print_usage (void);
 double calculate_percent(uintmax_t, uintmax_t);
 void stat_path (struct parameter_list *p);
+void do_stat_path (struct parameter_list *p);
 void get_stats (struct parameter_list *p, struct fs_usage *fsp);
 void get_path_stats (struct parameter_list *p, struct fs_usage *fsp);
 
@@ -989,6 +993,42 @@ print_usage (void)
 
 void
 stat_path (struct parameter_list *p)
+{
+#ifdef HAVE_PTHREAD_H
+  pthread_t stat_thread;
+  int status;
+  int statdone = 0;
+  int timer = timeout_interval;
+  struct timespec req, rem;
+  req.tv_sec = 0;
+  pthread_create(&stat_thread, NULL, do_stat_path, p);
+  while (timer-- > 0) {
+    req.tv_nsec = 10000000;
+    nanosleep(&req, &rem);
+    if (pthread_kill(stat_thread, 0)) {
+      statdone = 1;
+      break;
+    } else {
+      req.tv_nsec = 990000000;
+      nanosleep(&req, &rem);
+    }
+  }
+  if (statdone == 1) {
+    pthread_join(stat_thread, (void *)&status);
+  } else {
+    pthread_detach(stat_thread);
+    if (verbose >= 3)
+      printf("stat did not return within %ds on %s\n", timeout_interval, p->name);
+    printf("DISK %s - ", _("CRITICAL"));
+    die (STATE_CRITICAL, _("%s %s: %s\n"), p->name, _("hangs"), _("Timeout"));
+  }
+#else
+  do_stat_path(p);
+#endif
+}
+
+void
+do_stat_path (struct parameter_list *p)
 {
   /* Stat entry to check that dir exists and is accessible */
   if (verbose >= 3)