[PATCH] Implement git-checkout-cache -u to update stat information in the cache.

With -u flag, git-checkout-cache picks up the stat information
from newly created file and updates the cache.  This removes the
need to run git-update-cache --refresh immediately after running
git-checkout-cache.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 53 insertions, 0 deletions

diff --git a/index.c b/index.c
new file mode 100644
index 0000000000..87fc7b0387
--- /dev/null
+++ b/index.c
@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2005, Junio C Hamano
+ */
+#include <signal.h>
+#include "cache.h"
+
+static struct cache_file *cache_file_list;
+
+static void remove_lock_file(void)
+{
+	while (cache_file_list) {
+		if (cache_file_list->lockfile[0])
+			unlink(cache_file_list->lockfile);
+		cache_file_list = cache_file_list->next;
+	}
+}
+
+static void remove_lock_file_on_signal(int signo)
+{
+	remove_lock_file();
+}
+
+int hold_index_file_for_update(struct cache_file *cf, const char *path)
+{
+	sprintf(cf->lockfile, "%s.lock", path);
+	cf->next = cache_file_list;
+	cache_file_list = cf;
+	if (!cf->next) {
+		signal(SIGINT, remove_lock_file_on_signal);
+		atexit(remove_lock_file);
+	}
+	return open(cf->lockfile, O_RDWR | O_CREAT | O_EXCL, 0600);
+}
+
+int commit_index_file(struct cache_file *cf)
+{
+	char indexfile[PATH_MAX];
+	int i;
+	strcpy(indexfile, cf->lockfile);
+	i = strlen(indexfile) - 5; /* .lock */
+	indexfile[i] = 0;
+	i = rename(cf->lockfile, indexfile);
+	cf->lockfile[0] = 0;
+	return i;
+}
+
+void rollback_index_file(struct cache_file *cf)
+{
+	if (cf->lockfile[0])
+		unlink(cf->lockfile);
+	cf->lockfile[0] = 0;
+}
+