+ report("add '%s'", path);
+}
+
+static void read_index_info(int line_termination)
+{
+ struct strbuf buf;
+ strbuf_init(&buf);
+ while (1) {
+ char *ptr, *tab;
+ char *path_name;
+ unsigned char sha1[20];
+ unsigned int mode;
+ int stage;
+
+ /* This reads lines formatted in one of three formats:
+ *
+ * (1) mode SP sha1 TAB path
+ * The first format is what "git-apply --index-info"
+ * reports, and used to reconstruct a partial tree
+ * that is used for phony merge base tree when falling
+ * back on 3-way merge.
+ *
+ * (2) mode SP type SP sha1 TAB path
+ * The second format is to stuff git-ls-tree output
+ * into the index file.
+ *
+ * (3) mode SP sha1 SP stage TAB path
+ * This format is to put higher order stages into the
+ * index file and matches git-ls-files --stage output.
+ */
+ read_line(&buf, stdin, line_termination);
+ if (buf.eof)
+ break;
+
+ mode = strtoul(buf.buf, &ptr, 8);
+ if (ptr == buf.buf || *ptr != ' ')
+ goto bad_line;
+
+ tab = strchr(ptr, '\t');
+ if (!tab || tab - ptr < 41)
+ goto bad_line;
+
+ if (tab[-2] == ' ' && '0' <= tab[-1] && tab[-1] <= '3') {
+ stage = tab[-1] - '0';
+ ptr = tab + 1; /* point at the head of path */
+ tab = tab - 2; /* point at tail of sha1 */
+ }
+ else {
+ stage = 0;
+ ptr = tab + 1; /* point at the head of path */
+ }
+
+ if (get_sha1_hex(tab - 40, sha1) || tab[-41] != ' ')
+ goto bad_line;
+
+ if (line_termination && ptr[0] == '"')
+ path_name = unquote_c_style(ptr, NULL);
+ else
+ path_name = ptr;
+
+ if (!verify_path(path_name)) {
+ fprintf(stderr, "Ignoring path %s\n", path_name);
+ if (path_name != ptr)
+ free(path_name);
+ continue;
+ }
+
+ if (!mode) {
+ /* mode == 0 means there is no such path -- remove */
+ if (remove_file_from_cache(path_name))
+ die("git-update-index: unable to remove %s",
+ ptr);
+ }
+ else {
+ /* mode ' ' sha1 '\t' name
+ * ptr[-1] points at tab,
+ * ptr[-41] is at the beginning of sha1
+ */
+ ptr[-42] = ptr[-1] = 0;
+ if (add_cacheinfo(mode, sha1, path_name, stage))
+ die("git-update-index: unable to update %s",
+ path_name);
+ }
+ if (path_name != ptr)
+ free(path_name);
+ continue;
+
+ bad_line:
+ die("malformed index info %s", buf.buf);
+ }
+}
+
+static const char update_index_usage[] =
+"git-update-index [-q] [--add] [--replace] [--remove] [--unmerged] [--refresh] [--cacheinfo] [--chmod=(+|-)x] [--info-only] [--force-remove] [--stdin] [--index-info] [--ignore-missing] [-z] [--verbose] [--] <file>...";
+
+static unsigned char head_sha1[20];
+static unsigned char merge_head_sha1[20];
+
+static struct cache_entry *read_one_ent(const char *which,
+ unsigned char *ent, const char *path,
+ int namelen, int stage)
+{
+ unsigned mode;
+ unsigned char sha1[20];
+ int size;
+ struct cache_entry *ce;
+
+ if (get_tree_entry(ent, path, sha1, &mode)) {
+ error("%s: not in %s branch.", path, which);
+ return NULL;
+ }
+ if (mode == S_IFDIR) {
+ error("%s: not a blob in %s branch.", path, which);
+ return NULL;
+ }
+ size = cache_entry_size(namelen);
+ ce = xcalloc(1, size);
+
+ memcpy(ce->sha1, sha1, 20);
+ memcpy(ce->name, path, namelen);
+ ce->ce_flags = create_ce_flags(namelen, stage);
+ ce->ce_mode = create_ce_mode(mode);
+ return ce;
+}
+
+static int unresolve_one(const char *path)
+{
+ int namelen = strlen(path);
+ int pos;
+ int ret = 0;
+ struct cache_entry *ce_2 = NULL, *ce_3 = NULL;
+
+ /* See if there is such entry in the index. */
+ pos = cache_name_pos(path, namelen);
+ if (pos < 0) {
+ /* If there isn't, either it is unmerged, or
+ * resolved as "removed" by mistake. We do not
+ * want to do anything in the former case.
+ */
+ pos = -pos-1;
+ if (pos < active_nr) {
+ struct cache_entry *ce = active_cache[pos];
+ if (ce_namelen(ce) == namelen &&
+ !memcmp(ce->name, path, namelen)) {
+ fprintf(stderr,
+ "%s: skipping still unmerged path.\n",
+ path);
+ goto free_return;
+ }
+ }
+ }
+
+ /* Grab blobs from given path from HEAD and MERGE_HEAD,
+ * stuff HEAD version in stage #2,
+ * stuff MERGE_HEAD version in stage #3.
+ */
+ ce_2 = read_one_ent("our", head_sha1, path, namelen, 2);
+ ce_3 = read_one_ent("their", merge_head_sha1, path, namelen, 3);
+
+ if (!ce_2 || !ce_3) {
+ ret = -1;
+ goto free_return;
+ }
+ if (!memcmp(ce_2->sha1, ce_3->sha1, 20) &&
+ ce_2->ce_mode == ce_3->ce_mode) {
+ fprintf(stderr, "%s: identical in both, skipping.\n",
+ path);
+ goto free_return;
+ }
+
+ remove_file_from_cache(path);
+ if (add_cache_entry(ce_2, ADD_CACHE_OK_TO_ADD)) {
+ error("%s: cannot add our version to the index.", path);
+ ret = -1;
+ goto free_return;
+ }
+ if (!add_cache_entry(ce_3, ADD_CACHE_OK_TO_ADD))
+ return 0;
+ error("%s: cannot add their version to the index.", path);
+ ret = -1;
+ free_return:
+ free(ce_2);
+ free(ce_3);
+ return ret;
+}
+
+static void read_head_pointers(void)
+{
+ if (read_ref(git_path("HEAD"), head_sha1))
+ die("No HEAD -- no initial commit yet?\n");
+ if (read_ref(git_path("MERGE_HEAD"), merge_head_sha1)) {
+ fprintf(stderr, "Not in the middle of a merge.\n");
+ exit(0);
+ }
+}
+
+static int do_unresolve(int ac, const char **av)
+{
+ int i;
+ int err = 0;
+
+ /* Read HEAD and MERGE_HEAD; if MERGE_HEAD does not exist, we
+ * are not doing a merge, so exit with success status.
+ */
+ read_head_pointers();
+
+ for (i = 1; i < ac; i++) {
+ const char *arg = av[i];
+ err |= unresolve_one(arg);
+ }
+ return err;