1 files changed, 29 insertions, 0 deletions
diff --git a/sha1_file.c b/sha1_file.c
index 29f48d56b1..d91e072f3e 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -45,6 +45,35 @@ int get_sha1_hex(const char *hex, unsigned char *sha1)
 	return 0;
 }
 
+int get_sha1_file(const char *path, unsigned char *result)
+{
+	char buffer[60];
+	int fd = open(path, O_RDONLY);
+	int len;
+
+	if (fd < 0)
+		return -1;
+	len = read(fd, buffer, sizeof(buffer));
+	close(fd);
+	if (len < 40)
+		return -1;
+	return get_sha1_hex(buffer, result);
+}
+
+int get_sha1(const char *str, unsigned char *sha1)
+{
+	static char pathname[PATH_MAX];
+
+	if (!get_sha1_hex(str, sha1))
+		return 0;
+	if (!get_sha1_file(str, sha1))
+		return 0;
+	snprintf(pathname, sizeof(pathname), ".git/%s", str);
+	if (!get_sha1_file(pathname, sha1))
+		return 0;
+	return -1;
+}
+
 char * sha1_to_hex(const unsigned char *sha1)
 {
 	static char buffer[50];