index: make the index file format extensible.

[git.git] / cache-tree.c

diff --git a/cache-tree.c b/cache-tree.c
index b34b0bc..2146723 100644 (file)
--- a/cache-tree.c
+++ b/cache-tree.c
@@ -11,16 +11,18 @@ struct cache_tree *cache_tree(void)
        return it;
 }
 
-void cache_tree_free(struct cache_tree *it)
+void cache_tree_free(struct cache_tree **it_p)
 {
        int i;
+       struct cache_tree *it = *it_p;
 
        if (!it)
                return;
        for (i = 0; i < it->subtree_nr; i++)
-               cache_tree_free(it->down[i]->cache_tree);
+               cache_tree_free(&it->down[i]->cache_tree);
        free(it->down);
        free(it);
+       *it_p = NULL;
 }
 
 static struct cache_tree_sub *find_subtree(struct cache_tree *it,
@@ -78,7 +80,7 @@ void cache_tree_invalidate_path(struct cache_tree *it, const char *path)
                                break;
                }
                if (i < it->subtree_nr) {
-                       cache_tree_free(it->down[i]->cache_tree);
+                       cache_tree_free(&it->down[i]->cache_tree);
                        free(it->down[i]);
                        /* 0 1 2 3 4 5
                         *       ^     ^subtree_nr = 6
@@ -159,13 +161,27 @@ static void discard_unused_subtrees(struct cache_tree *it)
                if (s->used)
                        down[dst++] = s;
                else {
-                       cache_tree_free(s->cache_tree);
+                       cache_tree_free(&s->cache_tree);
                        free(s);
                        it->subtree_nr--;
                }
        }
 }
 
+int cache_tree_fully_valid(struct cache_tree *it)
+{
+       int i;
+       if (!it)
+               return 0;
+       if (it->entry_count < 0 || !has_sha1_file(it->sha1))
+               return 0;
+       for (i = 0; i < it->subtree_nr; i++) {
+               if (!cache_tree_fully_valid(it->down[i]->cache_tree))
+                       return 0;
+       }
+       return 1;
+}
+
 static int update_one(struct cache_tree *it,
                      struct cache_entry **cache,
                      int entries,
@@ -354,19 +370,15 @@ static void *write_one(struct cache_tree *it,
        return buffer;
 }
 
-static void *cache_tree_write(const unsigned char *cache_sha1,
-                             struct cache_tree *root,
-                             unsigned long *offset_p)
+void *cache_tree_write(struct cache_tree *root, unsigned long *size_p)
 {
        char path[PATH_MAX];
        unsigned long size = 8192;
        char *buffer = xmalloc(size);
 
-       /* the cache checksum of the corresponding index file. */
-       memcpy(buffer, cache_sha1, 20);
-       *offset_p = 20;
+       *size_p = 0;
        path[0] = 0;
-       return write_one(root, path, 0, buffer, &size, offset_p);
+       return write_one(root, path, 0, buffer, &size, size_p);
 }
 
 static struct cache_tree *read_one(const char **buffer, unsigned long *size_p)
@@ -439,81 +451,13 @@ static struct cache_tree *read_one(const char **buffer, unsigned long *size_p)
        return it;
 
  free_return:
-       cache_tree_free(it);
+       cache_tree_free(&it);
        return NULL;
 }
 
-static struct cache_tree *cache_tree_read(unsigned char *sha1,
-                                         const char *buffer,
-                                         unsigned long size)
+struct cache_tree *cache_tree_read(const char *buffer, unsigned long size)
 {
-       /* check the cache-tree matches the index */
-       if (memcmp(buffer, sha1, 20))
-               return NULL; /* checksum mismatch */
-       if (buffer[20])
+       if (buffer[0])
                return NULL; /* not the whole tree */
-       buffer += 20;
-       size -= 20;
        return read_one(&buffer, &size);
 }
-
-struct cache_tree *read_cache_tree(unsigned char *sha1)
-{
-       int fd;
-       struct stat st;
-       char path[PATH_MAX];
-       unsigned long size = 0;
-       void *map;
-       struct cache_tree *it;
-
-       sprintf(path, "%s.aux", get_index_file());
-       fd = open(path, O_RDONLY);
-       if (fd < 0)
-               return cache_tree();
-
-       if (fstat(fd, &st))
-               return cache_tree();
-       size = st.st_size;
-       map = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
-       close(fd);
-       if (map == MAP_FAILED)
-               return cache_tree();
-       it = cache_tree_read(sha1, map, size);
-       munmap(map, size);
-       if (!it)
-               return cache_tree();
-       return it;
-}
-
-int write_cache_tree(const unsigned char *sha1, struct cache_tree *root)
-{
-       char path[PATH_MAX];
-       unsigned long size = 0;
-       void *buf, *buffer;
-       int fd, ret = -1;
-
-       sprintf(path, "%s.aux", get_index_file());
-       if (!root) {
-               unlink(path);
-               return -1;
-       }
-       fd = open(path, O_WRONLY|O_CREAT, 0666);
-       if (fd < 0)
-               return -1;
-       buffer = buf = cache_tree_write(sha1, root, &size);
-       while (size) {
-               int written = xwrite(fd, buf, size);
-               if (written <= 0)
-                       goto fail;
-               buf += written;
-               size -= written;
-       }
-       ret = 0;
-
- fail:
-       close(fd);
-       free(buffer);
-       if (ret)
-               unlink(path);
-       return ret;
-}