[PATCH/RFC 2/2] receive-pack: hint that the user can stop "git push" at auto gc time

["Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>]

Housekeeping jobs like auto gc generally should not get in the way.
Users who are pushing may not want to wait until auto gc is done on
the server. Give a hint for those users that it's safe now to break
"git push" and stop waiting.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 This bandage patch may be a good compromise between running auto gc
 and not annoying users much.
 
 If I'm not mistaken, when ^C on "git push" this way, gc will still be
 running until it needs to print something out (which it should not
 normally because of --quiet). The user won't see gc errors, but the
 user generally can't do much anyway.

 builtin/gc.c           | 9 ++++++++-
 builtin/receive-pack.c | 2 +-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/builtin/gc.c b/builtin/gc.c
index c19545d..592271a 100644
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -253,6 +253,7 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 	int auto_gc = 0;
 	int quiet = 0;
 	int force = 0;
+	int break_ok = 0;
 	const char *name;
 	pid_t pid;
 
@@ -263,6 +264,8 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 			PARSE_OPT_OPTARG, NULL, (intptr_t)prune_expire },
 		OPT_BOOL(0, "aggressive", &aggressive, N_("be more thorough (increased runtime)")),
 		OPT_BOOL(0, "auto", &auto_gc, N_("enable auto-gc mode")),
+		OPT_HIDDEN_BOOL(0, "break-ok", &break_ok,
+				"hint that it is ok to stop the program"),
 		OPT_BOOL(0, "force", &force, N_("force running gc even if there may be another gc running")),
 		OPT_END()
 	};
@@ -301,7 +304,11 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 		 */
 		if (!need_to_gc())
 			return 0;
-		if (!quiet)
+		if (break_ok)
+			fprintf(stderr,
+				_("Auto packing the repository for optimum performance.\n"
+				  "It is safe to stop the program with Ctrl-C.\n"));
+		else if (!quiet)
 			fprintf(stderr,
 					_("Auto packing the repository for optimum performance. You may also\n"
 					"run \"git gc\" manually. See "
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index 82e2f76..68d16e0 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -1212,7 +1212,7 @@ int cmd_receive_pack(int argc, const char **argv, const char *prefix)
 			update_server_info(0);
 		if (auto_gc) {
 			const char *argv_gc_auto[] = {
-				"gc", "--auto", "--quiet", NULL,
+				"gc", "--auto", "--quiet", "--break-ok", NULL,
 			};
 			int opt = RUN_GIT_CMD | RUN_COMMAND_STDOUT_TO_STDERR;
 			run_command_v_opt(argv_gc_auto, opt);
-- 
1.8.5.2.240.g8478abd