Implement SIGHUP handling.

[dss.git] / signal.c

diff --git a/signal.c b/signal.c
index 160730f5b6e737f1256bf5117df736efd7d8f970..03926a47f23e29e40a3a8bf6dccccd5b460b96c0 100644 (file)
--- a/signal.c
+++ b/signal.c
@@ -69,7 +69,7 @@ err_out:
 static void generic_signal_handler(int s)
 {
        write(signal_pipe[1], &s, sizeof(int));
-       //fprintf(stderr, "got sig %i, write returned %d\n", s, ret);
+       //fprintf(stderr, "got sig %i\n", s);
 }
 
 /**
@@ -86,52 +86,56 @@ static void generic_signal_handler(int s)
  *
  * \sa waitpid(2)
  */
-int reap_child(pid_t *pid)
+int reap_child(pid_t *pid, int *status)
 {
-       int status;
-       *pid = waitpid(-1, &status, WNOHANG);
+       *pid = waitpid(-1, status, WNOHANG);
 
        if (!*pid)
                return 0;
        if (*pid < 0)
                return -ERRNO_TO_DSS_ERROR(errno);
-       if (WIFEXITED(status))
+       if (WIFEXITED(*status))
                DSS_DEBUG_LOG("child %i exited. Exit status: %i\n", (int)*pid,
-                       WEXITSTATUS(status));
-       else if (WIFSIGNALED(status))
+                       WEXITSTATUS(*status));
+       else if (WIFSIGNALED(*status))
                DSS_DEBUG_LOG("child %i was killed by signal %i\n", (int)*pid,
-                       WTERMSIG(status));
+                       WTERMSIG(*status));
        else
                DSS_WARNING_LOG("child %i terminated abormally\n", (int)*pid);
        return 1;
 }
 
 /**
- * wrapper around signal(2)
- * \param sig the number of the signal to catch
+ * Wrapper around signal(2)
+ *
+ * \param sig The number of the signal to catch.
  *
  * This installs the generic signal handler for the given signal.
+ *
  * \return This function returns 1 on success and \p -E_SIGNAL_SIG_ERR on errors.
  * \sa signal(2)
  */
 int install_sighandler(int sig)
 {
        DSS_DEBUG_LOG("catching signal %d\n", sig);
-       return signal(sig, &generic_signal_handler) == SIG_ERR?  -E_SIGNAL_SIG_ERR : 1;
+       if (signal(sig, &generic_signal_handler) != SIG_ERR)
+               return 1;
+       make_err_msg("signal %d", sig);
+       return -E_SIGNAL_SIG_ERR;
 }
 
 /**
- * return number of next pending signal
+ * Return number of next pending signal.
  *
  * This should be called if the fd for the signal pipe is ready for reading.
  *
- * \return On success, the number of the received signal is returned. \p
- * -E_SIGNAL_READ is returned if a read error occurred while reading the signal
- * pipe.  If the read was interrupted by another signal the function returns 0.
+ * \return On success, the number of the received signal is returned.
+ * If the read was interrupted by another signal the function returns 0.
+ * Otherwise a negative error code is returned.
  */
 int next_signal(void)
 {
-       int s;
+       int s, err;
        ssize_t r;
 
        r = read(signal_pipe[0], &s, sizeof(s));
@@ -139,7 +143,12 @@ int next_signal(void)
                DSS_DEBUG_LOG("next signal: %d\n", s);
                return s;
        }
-       return r < 0 && (errno != EAGAIN)? 0 : -ERRNO_TO_DSS_ERROR(errno);
+       err = errno;
+       assert(r < 0);
+       if (err == EAGAIN)
+               return 0;
+       make_err_msg("failed to read from signal pipe");
+       return -ERRNO_TO_DSS_ERROR(err);
 }
 
 /**