X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=signal.c;h=acc87802b33a841f8f5d7f90b971ae97a3edc3b0;hp=78e788d19021111b2f8ec712eb1ff8f0fd176375;hb=002731cd3938f3be6b71651e56c062af1adcdec0;hpb=ebb0565e946770c5b83c4d28c1f674dffdeaf551

diff --git a/signal.c b/signal.c
index 78e788d1..acc87802 100644
--- a/signal.c
+++ b/signal.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2004-2008 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2004-2009 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -57,8 +57,15 @@ 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);
+	ssize_t ret = write(signal_pipe[1], &s, sizeof(int));
+
+	if (ret == sizeof(int))
+		return;
+	if (ret < 0)
+		PARA_EMERG_LOG("%s\n", strerror(errno));
+	else
+		PARA_EMERG_LOG("short write to signal pipe\n");
+	exit(EXIT_FAILURE);
 }
 
 /**
@@ -73,7 +80,7 @@ static void generic_signal_handler(int s)
  * one otherwise. If and only if the function returns one, the content of \a
  * pid is meaningful.
  *
- * \sa waitpid(2)
+ * \sa waitpid(2).
  */
 int para_reap_child(pid_t *pid)
 {
@@ -110,12 +117,15 @@ void para_reap_children(void)
 }
 
 /**
- * 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)
+ *
+ * \sa signal(2).
  */
 int para_install_sighandler(int sig)
 {
@@ -124,29 +134,35 @@ int para_install_sighandler(int sig)
 }
 
 /**
- * return number of next pending signal
+ * Return the 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 returned zero or was interrupted by another signal the function returns
+ * 0.  Otherwise, a negative error value is returned.
  */
 int para_next_signal(void)
 {
 	int s;
-	ssize_t r;
+	ssize_t r = read(signal_pipe[0], &s, sizeof(s));
 
-	r = read(signal_pipe[0], &s, sizeof(s));
-	if (r == sizeof(s)) {
-		PARA_DEBUG_LOG("next signal: %d\n", s);
-		return s;
+	if (!r) {
+		PARA_CRIT_LOG("read from signal pipe returned zero\n");
+		return 0;
+	}
+	if (r < 0) {
+		if (errno == EAGAIN || errno == EINTR)
+			return 0;
+		return -ERRNO_TO_PARA_ERROR(errno);
 	}
-	return r < 0 && (errno != EAGAIN)? 0 : -E_SIGNAL_READ;
+	assert(r == sizeof(s));
+	PARA_DEBUG_LOG("next signal: %d\n", s);
+	return s;
 }
 
 /**
- * Close the signal pipe.
+ * Close the write end of the signal pipe.
  */
 void para_signal_shutdown(void)
 {