Merge lp:~cbehrens/agent-smith/signals into lp:agent-smith

[Chris Behrens]

Added signal handler.

=== modified file 'src/agent.c'
--- src/agent.c	2010-08-20 15:19:08 +0000
+++ src/agent.c	2010-08-25 03:57:43 +0000
@@ -19,6 +19,7 @@
 #include <malloc.h>
 #include <stdio.h>
 #include <string.h>
+#include <signal.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <sys/types.h>
@@ -27,8 +28,39 @@
 #include "spool.h"
 #include "xen.h"
 
+/*
+ * Global variables
+ */
+
 char *dispatcher = NULL;
-
+int agent_got_sigterm = 0;
+
+/*
+ * Private function prototypes
+ */
+static void _agent_signal_handler(int signum);
+
+/*
+ * Private functions
+ */
+static void _agent_signal_handler(int signum)
+{
+    switch(signum) {
+        case SIGCHLD:
+        case SIGPIPE:
+        case SIGHUP:
+            break;
+        case SIGTERM:
+            agent_got_sigterm = 1;
+            break;
+        default:
+            break;
+    }
+}
+
+/*
+ * Public functions
+ */
 void read_from_spool_and_send_to_xen(const char *msg) {
     char *buf = NULL, xs_path[255];
     const char *msgid;
@@ -68,8 +100,30 @@
     return 0;
 }
 
+
+int agent_setup_signals(void)
+{
+    struct sigaction sa;
+
+    memset(&sa, 0, sizeof(sa));
+    sa.sa_handler = _agent_signal_handler;
+
+    sigaction(SIGCHLD, &sa, NULL);
+    sigaction(SIGPIPE, &sa, NULL);
+    sigaction(SIGHUP, &sa, NULL);
+    sigaction(SIGTERM, &sa, NULL);
+
+    return 0;
+}
+
 int agent_init(const char *dispatcher_cmd) {
     AGENT_LOG0("Starting Agent Smith");
+
+    if (agent_setup_signals() < 0) {
+        AGENT_LOG0("Failed to initialise signal handlers");
+        return -1;
+    }
+
     if (xen_init() < 0) {
         AGENT_LOG0("Failed to initialise Xen connection");
         return -1;
@@ -104,5 +158,8 @@
 {
     spool_process_pending_events();
     xen_process_pending_events();
-    return 1;
+    if (agent_got_sigterm)
+        return 1;
+    return 0;
 }
+

=== modified file 'src/main.c'
--- src/main.c	2010-08-20 15:18:41 +0000
+++ src/main.c	2010-08-25 03:57:43 +0000
@@ -86,6 +86,7 @@
         return -1;
     }
 
-    while (agent_loop());
+    while (!agent_loop());
+
     return 0;
 }

=== modified file 'src/spool.h'
--- src/spool.h	2010-07-07 09:26:52 +0000
+++ src/spool.h	2010-08-25 03:57:43 +0000
@@ -21,6 +21,8 @@
 int spool_init(void);
 char *spool_incoming_dir(void);
 char *spool_outgoing_dir(void);
+int agent_setup_signals(void);
+
 /**
  * Store an incoming message in the spool
  *

=== modified file 'tests/check_agent.c'
--- tests/check_agent.c	2010-08-24 17:30:29 +0000
+++ tests/check_agent.c	2010-08-25 03:57:43 +0000
@@ -15,10 +15,11 @@
  */
 #include <stdio.h>
 #include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
 #include <check.h>
 #include <unistd.h>
-#include <sys/stat.h>
-#include <sys/wait.h>
 #include "../src/agent.h"
 #include "../src/xen.h"
 #include "../src/spool.h"
@@ -88,6 +89,19 @@
 }
 END_TEST
 
+START_TEST(test_agent_signals)
+{
+    fail_unless(agent_init("/bin/true") == 0, "agent_init() failed");
+
+    fail_unless(kill(getpid(), SIGCHLD) == 0);
+    fail_unless(kill(getpid(), SIGCHLD) == 0);
+    fail_unless(kill(getpid(), SIGPIPE) == 0);
+    fail_unless(kill(getpid(), SIGTERM) == 0);
+    /* agent_loop() should return != 0 for receiving SIGTERM */
+    fail_unless(agent_loop() != 0);
+}
+END_TEST
+
 Suite *agent_suite(void)
 {
     Suite *s = suite_create("Agent");
@@ -96,6 +110,7 @@
     tcase_add_checked_fixture(tc_agent, test_spool_to_xen_setup, test_spool_to_xen_teardown);
     tcase_add_test(tc_agent, test_spool_to_xen);
     tcase_add_test(tc_agent, test_xen_to_spool);
+    tcase_add_test(tc_agent, test_agent_signals);
     suite_add_tcase(s, tc_agent);
 
     return s;