We do not like "HEAD" as a new branch name

[git.git] / sha1_name.c

diff --git a/sha1_name.c b/sha1_name.c
index faac158..bf8f0f0 100644 (file)
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -203,11 +203,12 @@ const char *find_unique_abbrev(const unsigned char *sha1, int len)
        return NULL;
 }
 
-static int ambiguous_path(const char *path)
+static int ambiguous_path(const char *path, int len)
 {
        int slash = 1;
+       int cnt;
 
-       for (;;) {
+       for (cnt = 0; cnt < len; cnt++) {
                switch (*path++) {
                case '\0':
                        break;
@@ -224,6 +225,7 @@ static int ambiguous_path(const char *path)
                }
                return slash;
        }
+       return slash;
 }
 
 static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
@@ -242,26 +244,41 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
                return 0;
 
        /* Accept only unambiguous ref paths. */
-       if (ambiguous_path(str))
+       if (ambiguous_path(str, len))
                return -1;
 
        for (p = prefix; *p; p++) {
                char *pathname = git_path("%s/%.*s", *p, len, str);
+
                if (!read_ref(pathname, sha1)) {
                        /* Must be unique; i.e. when heads/foo and
                         * tags/foo are both present, reject "foo".
-                        * Note that read_ref() eventually calls
-                        * get_sha1_hex() which can smudge initial
-                        * part of the buffer even if what is read
-                        * is found to be invalid halfway.
                         */
                        if (1 < found++)
                                return -1;
                }
+
+               /* We want to allow .git/description file and
+                * "description" branch to exist at the same time.
+                * "git-rev-parse description" should silently skip
+                * .git/description file as a candidate for
+                * get_sha1().  However, having garbage file anywhere
+                * under refs/ is not OK, and we would not have caught
+                * ambiguous heads and tags with the above test.
+                */
+               else if (**p && !access(pathname, F_OK)) {
+                       /* Garbage exists under .git/refs */
+                       return error("garbage ref found '%s'", pathname);
+               }
        }
-       if (found == 1)
+       switch (found) {
+       case 0:
+               return -1;
+       case 1:
                return 0;
-       return -1;
+       default:
+               return error("ambiguous refname '%.*s'", len, str);
+       }
 }
 
 static int get_sha1_1(const char *name, int len, unsigned char *sha1);