Merge branch 'jc/ignore-sigpipe-while-running-hooks'

pre- and post-receive hooks are no longer required to read all
their inputs.

* jc/ignore-sigpipe-while-running-hooks:
  receive-pack: allow hooks to ignore its standard input stream

builtin/receive-pack.c

@@ -15,6 +15,7 @@
 #include "connected.h"
 #include "argv-array.h"
 #include "version.h"
+#include "sigchain.h"
 
 static const char receive_pack_usage[] = "git receive-pack <git-dir>";
 
@@ -287,6 +288,8 @@ static int run_and_feed_hook(const char *hook_name, feed_fn feed, void *feed_sta
 		return code;
 	}
 
+	sigchain_push(SIGPIPE, SIG_IGN);
+
 	while (1) {
 		const char *buf;
 		size_t n;
@@ -298,6 +301,9 @@ static int run_and_feed_hook(const char *hook_name, feed_fn feed, void *feed_sta
 	close(proc.in);
 	if (use_sideband)
 		finish_async(&muxer);
+
+	sigchain_pop(SIGPIPE);
+
 	return finish_command(&proc);
 }
 

t/t5401-update-hooks.sh

@@ -135,4 +135,17 @@ test_expect_success 'send-pack stderr contains hook messages' '
 	test_cmp expect actual
 '
 
+test_expect_success 'pre-receive hook that forgets to read its input' '
+	write_script victim.git/hooks/pre-receive <<-\EOF &&
+	exit 0
+	EOF
+	rm -f victim.git/hooks/update victim.git/hooks/post-update &&
+
+	for v in $(test_seq 100 999)
+	do
+		git branch branch_$v master || return
+	done &&
+	git push ./victim.git "+refs/heads/*:refs/heads/*"
+'
+
 test_done