- const char *argv[] = {
- "git-read-tree", NULL, "-m", NULL, NULL, NULL,
- NULL,
- };
- if (cache_dirty)
- flush_cache();
- argv[1] = update_arg;
- argv[3] = sha1_to_hex(common->object.sha1);
- argv[4] = sha1_to_hex(head->object.sha1);
- argv[5] = sha1_to_hex(merge->object.sha1);
- rc = run_command_v(6, argv);
- return rc < 0 ? -1: rc;
+ struct object_list *trees = NULL;
+ struct unpack_trees_options opts;
+
+ if (!cache_dirty) {
+ read_cache_from(getenv("GIT_INDEX_FILE"));
+ cache_dirty = 1;
+ }
+
+ memset(&opts, 0, sizeof(opts));
+ if (index_only)
+ opts.index_only = 1;
+ else
+ opts.update = 1;
+ opts.merge = 1;
+ opts.head_idx = 2;
+ opts.fn = threeway_merge;
+
+ object_list_append(&common->object, &trees);
+ object_list_append(&head->object, &trees);
+ object_list_append(&merge->object, &trees);
+
+ rc = unpack_trees(trees, &opts);
+ cache_tree_free(&active_cache_tree);
+
+ cache_dirty = 1;
+
+ return rc;