[PATCH 2/5] launch_editor: ignore SIGINT while the editor has control

[Jeff King <peff@peff.net>]

From: Paul Fox <pgf@foxharp.boston.ma.us>

The user's editor likely catches SIGINT (ctrl-C).  but if
the user spawns a command from the editor and uses ctrl-C to
kill that command, the SIGINT will likely also kill git
itself (depending on the editor, this can leave the terminal
in an unusable state).

Signed-off-by: Paul Fox <pgf@foxharp.boston.ma.us>
Signed-off-by: Jeff King <peff@peff.net>
---
Whoops, my original sending of this actually had Paul in the email's
From field, not in the pseudo-header of the commit. Apologies if you
receive an extra forged copy.

 editor.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/editor.c b/editor.c
index 842f782..28aae85 100644
--- a/editor.c
+++ b/editor.c
@@ -1,6 +1,7 @@
 #include "cache.h"
 #include "strbuf.h"
 #include "run-command.h"
+#include "sigchain.h"
 
 #ifndef DEFAULT_EDITOR
 #define DEFAULT_EDITOR "vi"
@@ -38,6 +39,7 @@ int launch_editor(const char *path, struct strbuf *buffer, const char *const *en
 	if (strcmp(editor, ":")) {
 		const char *args[] = { editor, path, NULL };
 		struct child_process p;
+		int ret;
 
 		memset(&p, 0, sizeof(p));
 		p.argv = args;
@@ -46,7 +48,10 @@ int launch_editor(const char *path, struct strbuf *buffer, const char *const *en
 		if (start_command(&p) < 0)
 			return error("unable to start editor '%s'", editor);
 
-		if (finish_command(&p))
+		sigchain_push(SIGINT, SIG_IGN);
+		ret = finish_command(&p);
+		sigchain_pop(SIGINT);
+		if (ret)
 			return error("There was a problem with the editor '%s'.",
 					editor);
 	}
-- 
1.8.0.207.gdf2154c