Add how-to on using update-hook.

diff --git a/tag.c b/tag.c
index 406dba2aa5607332fe022fcba1beb045fa61c5f4..b1ab75ff0164b0090f43ba55d2a70239ca2fdb7a 100644 (file)
--- a/tag.c
+++ b/tag.c
@@ -3,7 +3,14 @@
 
 const char *tag_type = "tag";
 
-struct tag *lookup_tag(unsigned char *sha1)
+struct object *deref_tag(struct object *o)
+{
+       while (o && o->type == tag_type)
+               o = parse_object(((struct tag *)o)->tagged->sha1);
+       return o;
+}
+
+struct tag *lookup_tag(const unsigned char *sha1)
 {
         struct object *obj = lookup_object(sha1);
         if (!obj) {
@@ -13,6 +20,8 @@ struct tag *lookup_tag(unsigned char *sha1)
                 ret->object.type = tag_type;
                 return ret;
         }
+       if (!obj->type)
+               obj->type = tag_type;
         if (obj->type != tag_type) {
                 error("Object %s is a %s, not a tree", 
                       sha1_to_hex(sha1), obj->type);
@@ -21,33 +30,22 @@ struct tag *lookup_tag(unsigned char *sha1)
         return (struct tag *) obj;
 }
 
-int parse_tag(struct tag *item)
+int parse_tag_buffer(struct tag *item, void *data, unsigned long size)
 {
-        char type[20];
-        void *data, *bufptr;
-        unsigned long size;
        int typelen, taglen;
        unsigned char object[20];
        const char *type_line, *tag_line, *sig_line;
+       char type[20];
 
         if (item->object.parsed)
                 return 0;
         item->object.parsed = 1;
-        data = bufptr = read_sha1_file(item->object.sha1, type, &size);
-        if (!data)
-                return error("Could not read %s",
-                             sha1_to_hex(item->object.sha1));
-        if (strcmp(type, tag_type))
-                return error("Object %s not a tag",
-                             sha1_to_hex(item->object.sha1));
 
        if (size < 64)
                return -1;
        if (memcmp("object ", data, 7) || get_sha1_hex(data + 7, object))
                return -1;
 
-       item->tagged = parse_object(object);
-
        type_line = data + 48;
        if (memcmp("\ntype ", type_line-1, 6))
                return -1;
@@ -64,10 +62,39 @@ int parse_tag(struct tag *item)
        typelen = tag_line - type_line - strlen("type \n");
        if (typelen >= 20)
                return -1;
+       memcpy(type, type_line + 5, typelen);
+       type[typelen] = '\0';
        taglen = sig_line - tag_line - strlen("tag \n");
        item->tag = xmalloc(taglen + 1);
        memcpy(item->tag, tag_line + 4, taglen);
        item->tag[taglen] = '\0';
 
+       item->tagged = lookup_object_type(object, type);
+       if (item->tagged)
+               add_ref(&item->object, item->tagged);
+
        return 0;
 }
+
+int parse_tag(struct tag *item)
+{
+       char type[20];
+       void *data;
+       unsigned long size;
+       int ret;
+
+       if (item->object.parsed)
+               return 0;
+       data = read_sha1_file(item->object.sha1, type, &size);
+       if (!data)
+               return error("Could not read %s",
+                            sha1_to_hex(item->object.sha1));
+       if (strcmp(type, tag_type)) {
+               free(data);
+               return error("Object %s not a tag",
+                            sha1_to_hex(item->object.sha1));
+       }
+       ret = parse_tag_buffer(item, data, size);
+       free(data);
+       return ret;
+}