check_by_ssh: fix child process leak on timeoutsrefs/pull/1583/head

When check_by_ssh runs into a timeout it simply exits keeping all child processes running.
Simply adopting the kill loop from runcmd_timeout_alarm_handler() fixes this.

Signed-off-by: Sven Nierlein <sven@nierlein.de>

4 files changed, 54 insertions, 25 deletions

diff --git a/lib/utils_base.c b/lib/utils_base.c
index 19a531f..fd7058d 100644
--- a/lib/utils_base.c
+++ b/lib/utils_base.c
@@ -37,6 +37,9 @@
 
 monitoring_plugin *this_monitoring_plugin=NULL;
 
+unsigned int timeout_state = STATE_CRITICAL;
+unsigned int timeout_interval = DEFAULT_SOCKET_TIMEOUT;
+
 int _np_state_read_file(FILE *);
 
 void np_init( char *plugin_name, int argc, char **argv ) {
@@ -359,6 +362,22 @@ char *np_extract_value(const char *varlist, const char *name, char sep) {
         return value;
 }
 
+const char *
+state_text (int result)
+{
+        switch (result) {
+        case STATE_OK:
+                return "OK";
+        case STATE_WARNING:
+                return "WARNING";
+        case STATE_CRITICAL:
+                return "CRITICAL";
+        case STATE_DEPENDENT:
+                return "DEPENDENT";
+        default:
+                return "UNKNOWN";
+        }
+}
 
 /*
  * Read a string representing a state (ok, warning... or numeric: 0, 1) and
diff --git a/lib/utils_base.h b/lib/utils_base.h
index 42ae0c0..d7e7dff 100644
--- a/lib/utils_base.h
+++ b/lib/utils_base.h
@@ -61,6 +61,10 @@ void print_thresholds(const char *, thresholds *);
 int check_range(double, range *);
 int get_status(double, thresholds *);
 
+/* Handle timeouts */
+extern unsigned int timeout_state;
+extern unsigned int timeout_interval;
+
 /* All possible characters in a threshold range */
 #define NP_THRESHOLDS_CHARS "-0123456789.:@~"
 
@@ -107,5 +111,6 @@ void np_state_write_string(time_t, char *);
 void np_init(char *, int argc, char **argv);
 void np_set_args(int argc, char **argv);
 void np_cleanup();
+const char *state_text (int);
 
 #endif /* _UTILS_BASE_ */
diff --git a/lib/utils_cmd.c b/lib/utils_cmd.c
index 7eb9a3a..795840d 100644
--- a/lib/utils_cmd.c
+++ b/lib/utils_cmd.c
@@ -40,6 +40,7 @@
 
 /** includes **/
 #include "common.h"
+#include "utils.h"
 #include "utils_cmd.h"
 #include "utils_base.h"
 #include <fcntl.h>
@@ -65,31 +66,6 @@ extern char **environ;
 # define SIG_ERR ((Sigfunc *)-1)
 #endif
 
-/* This variable must be global, since there's no way the caller
- * can forcibly slay a dead or ungainly running program otherwise.
- * Multithreading apps and plugins can initialize it (via CMD_INIT)
- * in an async safe manner PRIOR to calling cmd_run() or cmd_run_array()
- * for the first time.
- *
- * The check for initialized values is atomic and can
- * occur in any number of threads simultaneously. */
-static pid_t *_cmd_pids = NULL;
-
-/* Try sysconf(_SC_OPEN_MAX) first, as it can be higher than OPEN_MAX.
- * If that fails and the macro isn't defined, we fall back to an educated
- * guess. There's no guarantee that our guess is adequate and the program
- * will die with SIGSEGV if it isn't and the upper boundary is breached. */
-#define DEFAULT_MAXFD  256   /* fallback value if no max open files value is set */
-#define MAXFD_LIMIT   8192   /* upper limit of open files */
-#ifdef _SC_OPEN_MAX
-static long maxfd = 0;
-#elif defined(OPEN_MAX)
-# define maxfd OPEN_MAX
-#else   /* sysconf macro unavailable, so guess (may be wildly inaccurate) */
-# define maxfd DEFAULT_MAXFD
-#endif
-
-
 /** prototypes **/
 static int _cmd_open (char *const *, int *, int *)
         __attribute__ ((__nonnull__ (1, 2, 3)));
@@ -406,3 +382,19 @@ cmd_file_read ( char *filename, output *out, int flags)
 
         return 0;
 }
+
+void
+timeout_alarm_handler (int signo)
+{
+        size_t i;
+        if (signo == SIGALRM) {
+                printf (_("%s - Plugin timed out after %d seconds\n"),
+                                                state_text(timeout_state), timeout_interval);
+
+                if(_cmd_pids) for(i = 0; i < maxfd; i++) {
+                        if(_cmd_pids[i] != 0) kill(_cmd_pids[i], SIGKILL);
+                }
+
+                exit (timeout_state);
+        }
+}
diff --git a/lib/utils_cmd.h b/lib/utils_cmd.h
index ebaf15b..6f3aeb8 100644
--- a/lib/utils_cmd.h
+++ b/lib/utils_cmd.h
@@ -32,4 +32,17 @@ void cmd_init (void);
 #define CMD_NO_ARRAYS 0x01   /* don't populate arrays at all */
 #define CMD_NO_ASSOC 0x02    /* output.line won't point to buf */
 
+/* This variable must be global, since there's no way the caller
+ * can forcibly slay a dead or ungainly running program otherwise.
+ * Multithreading apps and plugins can initialize it (via CMD_INIT)
+ * in an async safe manner PRIOR to calling cmd_run() or cmd_run_array()
+ * for the first time.
+ *
+ * The check for initialized values is atomic and can
+ * occur in any number of threads simultaneously. */
+static pid_t *_cmd_pids = NULL;
+
+RETSIGTYPE timeout_alarm_handler (int);
+
+
 #endif /* _UTILS_CMD_ */