true built-in diff: run everything in-core.

diff --git a/sha1_name.c b/sha1_name.c
index bf8f0f0e1feef55ba6be764f60815d15036efa4e..d67de18ba5f5aa1f5b3dd1c5c81e75618d12e330 100644 (file)
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -143,7 +143,7 @@ static int find_unique_short_object(int len, char *canonical,
        }
        /* Both have unique ones -- do they match? */
        if (memcmp(packed_sha1, unpacked_sha1, 20))
-               return -2;
+               return SHORT_NAME_AMBIGUOUS;
        memcpy(sha1, packed_sha1, 20);
        return 0;
 }
@@ -155,7 +155,7 @@ static int get_short_sha1(const char *name, int len, unsigned char *sha1,
        char canonical[40];
        unsigned char res[20];
 
-       if (len < 4)
+       if (len < MINIMUM_ABBREV)
                return -1;
        memset(res, 0, 20);
        memset(canonical, 'x', 40);
@@ -186,13 +186,18 @@ static int get_short_sha1(const char *name, int len, unsigned char *sha1,
 
 const char *find_unique_abbrev(const unsigned char *sha1, int len)
 {
-       int status;
+       int status, is_null;
        static char hex[41];
+
+       is_null = !memcmp(sha1, null_sha1, 20);
        memcpy(hex, sha1_to_hex(sha1), 40);
+       if (len == 40)
+               return hex;
        while (len < 40) {
                unsigned char sha1_ret[20];
                status = get_short_sha1(hex, len, sha1_ret, 1);
-               if (!status) {
+               if (!status ||
+                   (is_null && status != SHORT_NAME_AMBIGUOUS)) {
                        hex[len] = 0;
                        return hex;
                }
@@ -223,7 +228,7 @@ static int ambiguous_path(const char *path, int len)
                        slash = 0;
                        continue;
                }
-               return slash;
+               break;
        }
        return slash;
 }
@@ -238,7 +243,6 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
                NULL
        };
        const char **p;
-       int found = 0;
 
        if (len == 40 && !get_sha1_hex(str, sha1))
                return 0;
@@ -249,36 +253,10 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
 
        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".
-                        */
-                       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);
-               }
-       }
-       switch (found) {
-       case 0:
-               return -1;
-       case 1:
-               return 0;
-       default:
-               return error("ambiguous refname '%.*s'", len, str);
+               if (!read_ref(pathname, sha1))
+                       return 0;
        }
+       return -1;
 }
 
 static int get_sha1_1(const char *name, int len, unsigned char *sha1);
@@ -412,43 +390,36 @@ static int peel_onion(const char *name, int len, unsigned char *sha1)
 
 static int get_sha1_1(const char *name, int len, unsigned char *sha1)
 {
-       int parent, ret;
+       int ret, has_suffix;
        const char *cp;
 
-       /* foo^[0-9] or foo^ (== foo^1); we do not do more than 9 parents. */
-       if (len > 2 && name[len-2] == '^' &&
-           name[len-1] >= '0' && name[len-1] <= '9') {
-               parent = name[len-1] - '0';
-               len -= 2;
-       }
-       else if (len > 1 && name[len-1] == '^') {
-               parent = 1;
-               len--;
-       } else
-               parent = -1;
-
-       if (parent >= 0)
-               return get_parent(name, len, sha1, parent);
-
        /* "name~3" is "name^^^",
-        * "name~12" is "name^^^^^^^^^^^^", and
         * "name~" and "name~0" are name -- not "name^0"!
+        * "name^" is not "name^0"; it is "name^1".
         */
-       parent = 0;
+       has_suffix = 0;
        for (cp = name + len - 1; name <= cp; cp--) {
                int ch = *cp;
                if ('0' <= ch && ch <= '9')
                        continue;
-               if (ch != '~')
-                       parent = -1;
+               if (ch == '~' || ch == '^')
+                       has_suffix = ch;
                break;
        }
-       if (!parent && *cp == '~') {
+
+       if (has_suffix) {
+               int num = 0;
                int len1 = cp - name;
                cp++;
                while (cp < name + len)
-                       parent = parent * 10 + *cp++ - '0';
-               return get_nth_ancestor(name, len1, sha1, parent);
+                       num = num * 10 + *cp++ - '0';
+               if (has_suffix == '^') {
+                       if (!num && len1 == len - 1)
+                               num = 1;
+                       return get_parent(name, len1, sha1, num);
+               }
+               /* else if (has_suffix == '~') -- goes without saying */
+               return get_nth_ancestor(name, len1, sha1, num);
        }
 
        ret = peel_onion(name, len, sha1);