[pacman-dev] [PATCH 2/6] dload: move (un)masking of signals to separate functions

[Dave Reisner]

Signed-off-by: Dave Reisner <dreisner at archlinux.org>
---
mask_signal doesn't get inlined here, but unmask does.

 lib/libalpm/dload.c |   43 +++++++++++++++++++++++++------------------
 1 files changed, 25 insertions(+), 18 deletions(-)

diff --git a/lib/libalpm/dload.c b/lib/libalpm/dload.c
index 16b2206..f8c10fa 100644
--- a/lib/libalpm/dload.c
+++ b/lib/libalpm/dload.c
@@ -67,7 +67,6 @@ static char *get_fullpath(const char *path, const char *filename,
 }
 
 #define check_stop() if(dload_interrupted) { ret = -1; goto cleanup; }
-enum sighandlers { OLD = 0, NEW = 1 };
 
 static int dload_interrupted;
 static void inthandler(int UNUSED signum)
@@ -234,6 +233,25 @@ static int curl_set_handle_opts(struct dload_payload *payload,
 	return 0;
 }
 
+/* set new sighandler, and return the original */
+static struct sigaction mask_signal(int signal, void (*handler)(int))
+{
+	struct sigaction newaction, origaction;
+
+	newaction.sa_handler = handler;
+	sigemptyset(&newaction.sa_mask);
+	newaction.sa_flags = 0;
+
+	sigaction(signal, NULL, &origaction);
+	sigaction(signal, &newaction, NULL);
+
+	return origaction;
+}
+
+static void unmask_signal(int signal, struct sigaction sa)
+{
+	sigaction(signal, &sa, NULL);
+}
 
 static int curl_download_internal(struct dload_payload *payload,
 		const char *localpath, char **final_file)
@@ -247,7 +265,7 @@ static int curl_download_internal(struct dload_payload *payload,
 	char error_buffer[CURL_ERROR_SIZE] = { 0 };
 	long timecond, remote_time = -1;
 	double remote_size, bytes_dl;
-	struct sigaction sig_pipe[2], sig_int[2];
+	struct sigaction sig_pipe, sig_int;
 	/* shortcut to our handle within the payload */
 	alpm_handle_t *handle = payload->handle;
 	handle->pm_errno = 0;
@@ -294,20 +312,9 @@ static int curl_download_internal(struct dload_payload *payload,
 		goto cleanup;
 	}
 
-	/* ignore any SIGPIPE signals- these may occur if our FTP socket dies or
-	 * something along those lines. Store the old signal handler first. */
-	sig_pipe[NEW].sa_handler = SIG_IGN;
-	sigemptyset(&sig_pipe[NEW].sa_mask);
-	sig_pipe[NEW].sa_flags = 0;
-	sigaction(SIGPIPE, NULL, &sig_pipe[OLD]);
-	sigaction(SIGPIPE, &sig_pipe[NEW], NULL);
-
-	dload_interrupted = 0;
-	sig_int[NEW].sa_handler = &inthandler;
-	sigemptyset(&sig_int[NEW].sa_mask);
-	sig_int[NEW].sa_flags = 0;
-	sigaction(SIGINT, NULL, &sig_int[OLD]);
-	sigaction(SIGINT, &sig_int[NEW], NULL);
+	/* ignore SIGPIPE and SIGINT signals while we're transferring */
+	sig_pipe = mask_signal(SIGPIPE, SIG_IGN);
+	sig_int = mask_signal(SIGINT, &inthandler);
 
 	/* Progress 0 - initialize */
 	prevprogress = 0;
@@ -414,8 +421,8 @@ cleanup:
 	FREE(destfile);
 
 	/* restore the old signal handlers */
-	sigaction(SIGINT, &sig_int[OLD], NULL);
-	sigaction(SIGPIPE, &sig_pipe[OLD], NULL);
+	unmask_signal(SIGINT, sig_int);
+	unmask_signal(SIGPIPE, sig_pipe);
 	/* if we were interrupted, trip the old handler */
 	if(dload_interrupted) {
 		raise(SIGINT);
-- 
1.7.6