From: Junio C Hamano <gitster@pobox.com>
Date: Wed, 1 Feb 2012 06:01:14 +0000 (-0800)
Subject: Merge branch 'rr/sequencer'
X-Git-Tag: v1.7.10-rc0~132
X-Git-Url: https://git.tokkee.org/?a=commitdiff_plain;h=7010146f90abf0e4954690f6cd38a8463786fec7;p=git.git

Merge branch 'rr/sequencer'

* rr/sequencer:
  sequencer: factor code out of revert builtin
  revert: prepare to move replay_action to header

Conflicts:
	builtin/revert.c
---

7010146f90abf0e4954690f6cd38a8463786fec7
diff --cc sequencer.c
index d1f28a694,54771196c..5fcbcb887
--- a/sequencer.c
+++ b/sequencer.c
@@@ -11,3 -24,906 +24,905 @@@ void remove_sequencer_state(void
  	remove_dir_recursively(&seq_dir, 0);
  	strbuf_release(&seq_dir);
  }
+ 
+ static const char *action_name(const struct replay_opts *opts)
+ {
+ 	return opts->action == REPLAY_REVERT ? "revert" : "cherry-pick";
+ }
+ 
+ static char *get_encoding(const char *message);
+ 
+ struct commit_message {
+ 	char *parent_label;
+ 	const char *label;
+ 	const char *subject;
+ 	char *reencoded_message;
+ 	const char *message;
+ };
+ 
+ static int get_message(struct commit *commit, struct commit_message *out)
+ {
+ 	const char *encoding;
+ 	const char *abbrev, *subject;
+ 	int abbrev_len, subject_len;
+ 	char *q;
+ 
+ 	if (!commit->buffer)
+ 		return -1;
+ 	encoding = get_encoding(commit->buffer);
+ 	if (!encoding)
+ 		encoding = "UTF-8";
+ 	if (!git_commit_encoding)
+ 		git_commit_encoding = "UTF-8";
+ 
+ 	out->reencoded_message = NULL;
+ 	out->message = commit->buffer;
+ 	if (strcmp(encoding, git_commit_encoding))
+ 		out->reencoded_message = reencode_string(commit->buffer,
+ 					git_commit_encoding, encoding);
+ 	if (out->reencoded_message)
+ 		out->message = out->reencoded_message;
+ 
+ 	abbrev = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
+ 	abbrev_len = strlen(abbrev);
+ 
+ 	subject_len = find_commit_subject(out->message, &subject);
+ 
+ 	out->parent_label = xmalloc(strlen("parent of ") + abbrev_len +
+ 			      strlen("... ") + subject_len + 1);
+ 	q = out->parent_label;
+ 	q = mempcpy(q, "parent of ", strlen("parent of "));
+ 	out->label = q;
+ 	q = mempcpy(q, abbrev, abbrev_len);
+ 	q = mempcpy(q, "... ", strlen("... "));
+ 	out->subject = q;
+ 	q = mempcpy(q, subject, subject_len);
+ 	*q = '\0';
+ 	return 0;
+ }
+ 
+ static void free_message(struct commit_message *msg)
+ {
+ 	free(msg->parent_label);
+ 	free(msg->reencoded_message);
+ }
+ 
+ static char *get_encoding(const char *message)
+ {
+ 	const char *p = message, *eol;
+ 
+ 	while (*p && *p != '\n') {
+ 		for (eol = p + 1; *eol && *eol != '\n'; eol++)
+ 			; /* do nothing */
+ 		if (!prefixcmp(p, "encoding ")) {
+ 			char *result = xmalloc(eol - 8 - p);
+ 			strlcpy(result, p + 9, eol - 8 - p);
+ 			return result;
+ 		}
+ 		p = eol;
+ 		if (*p == '\n')
+ 			p++;
+ 	}
+ 	return NULL;
+ }
+ 
+ static void write_cherry_pick_head(struct commit *commit, const char *pseudoref)
+ {
+ 	const char *filename;
+ 	int fd;
+ 	struct strbuf buf = STRBUF_INIT;
+ 
+ 	strbuf_addf(&buf, "%s\n", sha1_to_hex(commit->object.sha1));
+ 
+ 	filename = git_path("%s", pseudoref);
+ 	fd = open(filename, O_WRONLY | O_CREAT, 0666);
+ 	if (fd < 0)
+ 		die_errno(_("Could not open '%s' for writing"), filename);
+ 	if (write_in_full(fd, buf.buf, buf.len) != buf.len || close(fd))
+ 		die_errno(_("Could not write to '%s'"), filename);
+ 	strbuf_release(&buf);
+ }
+ 
+ static void print_advice(int show_hint)
+ {
+ 	char *msg = getenv("GIT_CHERRY_PICK_HELP");
+ 
+ 	if (msg) {
+ 		fprintf(stderr, "%s\n", msg);
+ 		/*
+ 		 * A conflict has occured but the porcelain
+ 		 * (typically rebase --interactive) wants to take care
+ 		 * of the commit itself so remove CHERRY_PICK_HEAD
+ 		 */
+ 		unlink(git_path("CHERRY_PICK_HEAD"));
+ 		return;
+ 	}
+ 
 -	if (show_hint) {
 -		advise("after resolving the conflicts, mark the corrected paths");
 -		advise("with 'git add <paths>' or 'git rm <paths>'");
 -		advise("and commit the result with 'git commit'");
 -	}
++	if (show_hint)
++		advise(_("after resolving the conflicts, mark the corrected paths\n"
++			 "with 'git add <paths>' or 'git rm <paths>'\n"
++			 "and commit the result with 'git commit'"));
+ }
+ 
+ static void write_message(struct strbuf *msgbuf, const char *filename)
+ {
+ 	static struct lock_file msg_file;
+ 
+ 	int msg_fd = hold_lock_file_for_update(&msg_file, filename,
+ 					       LOCK_DIE_ON_ERROR);
+ 	if (write_in_full(msg_fd, msgbuf->buf, msgbuf->len) < 0)
+ 		die_errno(_("Could not write to %s"), filename);
+ 	strbuf_release(msgbuf);
+ 	if (commit_lock_file(&msg_file) < 0)
+ 		die(_("Error wrapping up %s"), filename);
+ }
+ 
+ static struct tree *empty_tree(void)
+ {
+ 	return lookup_tree((const unsigned char *)EMPTY_TREE_SHA1_BIN);
+ }
+ 
+ static int error_dirty_index(struct replay_opts *opts)
+ {
+ 	if (read_cache_unmerged())
+ 		return error_resolve_conflict(action_name(opts));
+ 
+ 	/* Different translation strings for cherry-pick and revert */
+ 	if (opts->action == REPLAY_PICK)
+ 		error(_("Your local changes would be overwritten by cherry-pick."));
+ 	else
+ 		error(_("Your local changes would be overwritten by revert."));
+ 
+ 	if (advice_commit_before_merge)
+ 		advise(_("Commit your changes or stash them to proceed."));
+ 	return -1;
+ }
+ 
+ static int fast_forward_to(const unsigned char *to, const unsigned char *from)
+ {
+ 	struct ref_lock *ref_lock;
+ 
+ 	read_cache();
+ 	if (checkout_fast_forward(from, to))
+ 		exit(1); /* the callee should have complained already */
+ 	ref_lock = lock_any_ref_for_update("HEAD", from, 0);
+ 	return write_ref_sha1(ref_lock, to, "cherry-pick");
+ }
+ 
+ static int do_recursive_merge(struct commit *base, struct commit *next,
+ 			      const char *base_label, const char *next_label,
+ 			      unsigned char *head, struct strbuf *msgbuf,
+ 			      struct replay_opts *opts)
+ {
+ 	struct merge_options o;
+ 	struct tree *result, *next_tree, *base_tree, *head_tree;
+ 	int clean, index_fd;
+ 	const char **xopt;
+ 	static struct lock_file index_lock;
+ 
+ 	index_fd = hold_locked_index(&index_lock, 1);
+ 
+ 	read_cache();
+ 
+ 	init_merge_options(&o);
+ 	o.ancestor = base ? base_label : "(empty tree)";
+ 	o.branch1 = "HEAD";
+ 	o.branch2 = next ? next_label : "(empty tree)";
+ 
+ 	head_tree = parse_tree_indirect(head);
+ 	next_tree = next ? next->tree : empty_tree();
+ 	base_tree = base ? base->tree : empty_tree();
+ 
+ 	for (xopt = opts->xopts; xopt != opts->xopts + opts->xopts_nr; xopt++)
+ 		parse_merge_opt(&o, *xopt);
+ 
+ 	clean = merge_trees(&o,
+ 			    head_tree,
+ 			    next_tree, base_tree, &result);
+ 
+ 	if (active_cache_changed &&
+ 	    (write_cache(index_fd, active_cache, active_nr) ||
+ 	     commit_locked_index(&index_lock)))
+ 		/* TRANSLATORS: %s will be "revert" or "cherry-pick" */
+ 		die(_("%s: Unable to write new index file"), action_name(opts));
+ 	rollback_lock_file(&index_lock);
+ 
+ 	if (!clean) {
+ 		int i;
+ 		strbuf_addstr(msgbuf, "\nConflicts:\n\n");
+ 		for (i = 0; i < active_nr;) {
+ 			struct cache_entry *ce = active_cache[i++];
+ 			if (ce_stage(ce)) {
+ 				strbuf_addch(msgbuf, '\t');
+ 				strbuf_addstr(msgbuf, ce->name);
+ 				strbuf_addch(msgbuf, '\n');
+ 				while (i < active_nr && !strcmp(ce->name,
+ 						active_cache[i]->name))
+ 					i++;
+ 			}
+ 		}
+ 	}
+ 
+ 	return !clean;
+ }
+ 
+ /*
+  * If we are cherry-pick, and if the merge did not result in
+  * hand-editing, we will hit this commit and inherit the original
+  * author date and name.
+  * If we are revert, or if our cherry-pick results in a hand merge,
+  * we had better say that the current user is responsible for that.
+  */
+ static int run_git_commit(const char *defmsg, struct replay_opts *opts)
+ {
+ 	/* 6 is max possible length of our args array including NULL */
+ 	const char *args[6];
+ 	int i = 0;
+ 
+ 	args[i++] = "commit";
+ 	args[i++] = "-n";
+ 	if (opts->signoff)
+ 		args[i++] = "-s";
+ 	if (!opts->edit) {
+ 		args[i++] = "-F";
+ 		args[i++] = defmsg;
+ 	}
+ 	args[i] = NULL;
+ 
+ 	return run_command_v_opt(args, RUN_GIT_CMD);
+ }
+ 
+ static int do_pick_commit(struct commit *commit, struct replay_opts *opts)
+ {
+ 	unsigned char head[20];
+ 	struct commit *base, *next, *parent;
+ 	const char *base_label, *next_label;
+ 	struct commit_message msg = { NULL, NULL, NULL, NULL, NULL };
+ 	char *defmsg = NULL;
+ 	struct strbuf msgbuf = STRBUF_INIT;
+ 	int res;
+ 
+ 	if (opts->no_commit) {
+ 		/*
+ 		 * We do not intend to commit immediately.  We just want to
+ 		 * merge the differences in, so let's compute the tree
+ 		 * that represents the "current" state for merge-recursive
+ 		 * to work on.
+ 		 */
+ 		if (write_cache_as_tree(head, 0, NULL))
+ 			die (_("Your index file is unmerged."));
+ 	} else {
+ 		if (get_sha1("HEAD", head))
+ 			return error(_("You do not have a valid HEAD"));
+ 		if (index_differs_from("HEAD", 0))
+ 			return error_dirty_index(opts);
+ 	}
+ 	discard_cache();
+ 
+ 	if (!commit->parents) {
+ 		parent = NULL;
+ 	}
+ 	else if (commit->parents->next) {
+ 		/* Reverting or cherry-picking a merge commit */
+ 		int cnt;
+ 		struct commit_list *p;
+ 
+ 		if (!opts->mainline)
+ 			return error(_("Commit %s is a merge but no -m option was given."),
+ 				sha1_to_hex(commit->object.sha1));
+ 
+ 		for (cnt = 1, p = commit->parents;
+ 		     cnt != opts->mainline && p;
+ 		     cnt++)
+ 			p = p->next;
+ 		if (cnt != opts->mainline || !p)
+ 			return error(_("Commit %s does not have parent %d"),
+ 				sha1_to_hex(commit->object.sha1), opts->mainline);
+ 		parent = p->item;
+ 	} else if (0 < opts->mainline)
+ 		return error(_("Mainline was specified but commit %s is not a merge."),
+ 			sha1_to_hex(commit->object.sha1));
+ 	else
+ 		parent = commit->parents->item;
+ 
+ 	if (opts->allow_ff && parent && !hashcmp(parent->object.sha1, head))
+ 		return fast_forward_to(commit->object.sha1, head);
+ 
+ 	if (parent && parse_commit(parent) < 0)
+ 		/* TRANSLATORS: The first %s will be "revert" or
+ 		   "cherry-pick", the second %s a SHA1 */
+ 		return error(_("%s: cannot parse parent commit %s"),
+ 			action_name(opts), sha1_to_hex(parent->object.sha1));
+ 
+ 	if (get_message(commit, &msg) != 0)
+ 		return error(_("Cannot get commit message for %s"),
+ 			sha1_to_hex(commit->object.sha1));
+ 
+ 	/*
+ 	 * "commit" is an existing commit.  We would want to apply
+ 	 * the difference it introduces since its first parent "prev"
+ 	 * on top of the current HEAD if we are cherry-pick.  Or the
+ 	 * reverse of it if we are revert.
+ 	 */
+ 
+ 	defmsg = git_pathdup("MERGE_MSG");
+ 
+ 	if (opts->action == REPLAY_REVERT) {
+ 		base = commit;
+ 		base_label = msg.label;
+ 		next = parent;
+ 		next_label = msg.parent_label;
+ 		strbuf_addstr(&msgbuf, "Revert \"");
+ 		strbuf_addstr(&msgbuf, msg.subject);
+ 		strbuf_addstr(&msgbuf, "\"\n\nThis reverts commit ");
+ 		strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
+ 
+ 		if (commit->parents && commit->parents->next) {
+ 			strbuf_addstr(&msgbuf, ", reversing\nchanges made to ");
+ 			strbuf_addstr(&msgbuf, sha1_to_hex(parent->object.sha1));
+ 		}
+ 		strbuf_addstr(&msgbuf, ".\n");
+ 	} else {
+ 		const char *p;
+ 
+ 		base = parent;
+ 		base_label = msg.parent_label;
+ 		next = commit;
+ 		next_label = msg.label;
+ 
+ 		/*
+ 		 * Append the commit log message to msgbuf; it starts
+ 		 * after the tree, parent, author, committer
+ 		 * information followed by "\n\n".
+ 		 */
+ 		p = strstr(msg.message, "\n\n");
+ 		if (p) {
+ 			p += 2;
+ 			strbuf_addstr(&msgbuf, p);
+ 		}
+ 
+ 		if (opts->record_origin) {
+ 			strbuf_addstr(&msgbuf, "(cherry picked from commit ");
+ 			strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
+ 			strbuf_addstr(&msgbuf, ")\n");
+ 		}
+ 	}
+ 
+ 	if (!opts->strategy || !strcmp(opts->strategy, "recursive") || opts->action == REPLAY_REVERT) {
+ 		res = do_recursive_merge(base, next, base_label, next_label,
+ 					 head, &msgbuf, opts);
+ 		write_message(&msgbuf, defmsg);
+ 	} else {
+ 		struct commit_list *common = NULL;
+ 		struct commit_list *remotes = NULL;
+ 
+ 		write_message(&msgbuf, defmsg);
+ 
+ 		commit_list_insert(base, &common);
+ 		commit_list_insert(next, &remotes);
+ 		res = try_merge_command(opts->strategy, opts->xopts_nr, opts->xopts,
+ 					common, sha1_to_hex(head), remotes);
+ 		free_commit_list(common);
+ 		free_commit_list(remotes);
+ 	}
+ 
+ 	/*
+ 	 * If the merge was clean or if it failed due to conflict, we write
+ 	 * CHERRY_PICK_HEAD for the subsequent invocation of commit to use.
+ 	 * However, if the merge did not even start, then we don't want to
+ 	 * write it at all.
+ 	 */
+ 	if (opts->action == REPLAY_PICK && !opts->no_commit && (res == 0 || res == 1))
+ 		write_cherry_pick_head(commit, "CHERRY_PICK_HEAD");
+ 	if (opts->action == REPLAY_REVERT && ((opts->no_commit && res == 0) || res == 1))
+ 		write_cherry_pick_head(commit, "REVERT_HEAD");
+ 
+ 	if (res) {
+ 		error(opts->action == REPLAY_REVERT
+ 		      ? _("could not revert %s... %s")
+ 		      : _("could not apply %s... %s"),
+ 		      find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV),
+ 		      msg.subject);
+ 		print_advice(res == 1);
+ 		rerere(opts->allow_rerere_auto);
+ 	} else {
+ 		if (!opts->no_commit)
+ 			res = run_git_commit(defmsg, opts);
+ 	}
+ 
+ 	free_message(&msg);
+ 	free(defmsg);
+ 
+ 	return res;
+ }
+ 
+ static void prepare_revs(struct replay_opts *opts)
+ {
+ 	if (opts->action != REPLAY_REVERT)
+ 		opts->revs->reverse ^= 1;
+ 
+ 	if (prepare_revision_walk(opts->revs))
+ 		die(_("revision walk setup failed"));
+ 
+ 	if (!opts->revs->commits)
+ 		die(_("empty commit set passed"));
+ }
+ 
+ static void read_and_refresh_cache(struct replay_opts *opts)
+ {
+ 	static struct lock_file index_lock;
+ 	int index_fd = hold_locked_index(&index_lock, 0);
+ 	if (read_index_preload(&the_index, NULL) < 0)
+ 		die(_("git %s: failed to read the index"), action_name(opts));
+ 	refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, NULL, NULL, NULL);
+ 	if (the_index.cache_changed) {
+ 		if (write_index(&the_index, index_fd) ||
+ 		    commit_locked_index(&index_lock))
+ 			die(_("git %s: failed to refresh the index"), action_name(opts));
+ 	}
+ 	rollback_lock_file(&index_lock);
+ }
+ 
+ /*
+  * Append a commit to the end of the commit_list.
+  *
+  * next starts by pointing to the variable that holds the head of an
+  * empty commit_list, and is updated to point to the "next" field of
+  * the last item on the list as new commits are appended.
+  *
+  * Usage example:
+  *
+  *     struct commit_list *list;
+  *     struct commit_list **next = &list;
+  *
+  *     next = commit_list_append(c1, next);
+  *     next = commit_list_append(c2, next);
+  *     assert(commit_list_count(list) == 2);
+  *     return list;
+  */
+ static struct commit_list **commit_list_append(struct commit *commit,
+ 					       struct commit_list **next)
+ {
+ 	struct commit_list *new = xmalloc(sizeof(struct commit_list));
+ 	new->item = commit;
+ 	*next = new;
+ 	new->next = NULL;
+ 	return &new->next;
+ }
+ 
+ static int format_todo(struct strbuf *buf, struct commit_list *todo_list,
+ 		struct replay_opts *opts)
+ {
+ 	struct commit_list *cur = NULL;
+ 	const char *sha1_abbrev = NULL;
+ 	const char *action_str = opts->action == REPLAY_REVERT ? "revert" : "pick";
+ 	const char *subject;
+ 	int subject_len;
+ 
+ 	for (cur = todo_list; cur; cur = cur->next) {
+ 		sha1_abbrev = find_unique_abbrev(cur->item->object.sha1, DEFAULT_ABBREV);
+ 		subject_len = find_commit_subject(cur->item->buffer, &subject);
+ 		strbuf_addf(buf, "%s %s %.*s\n", action_str, sha1_abbrev,
+ 			subject_len, subject);
+ 	}
+ 	return 0;
+ }
+ 
+ static struct commit *parse_insn_line(char *bol, char *eol, struct replay_opts *opts)
+ {
+ 	unsigned char commit_sha1[20];
+ 	enum replay_action action;
+ 	char *end_of_object_name;
+ 	int saved, status, padding;
+ 
+ 	if (!prefixcmp(bol, "pick")) {
+ 		action = REPLAY_PICK;
+ 		bol += strlen("pick");
+ 	} else if (!prefixcmp(bol, "revert")) {
+ 		action = REPLAY_REVERT;
+ 		bol += strlen("revert");
+ 	} else
+ 		return NULL;
+ 
+ 	/* Eat up extra spaces/ tabs before object name */
+ 	padding = strspn(bol, " \t");
+ 	if (!padding)
+ 		return NULL;
+ 	bol += padding;
+ 
+ 	end_of_object_name = bol + strcspn(bol, " \t\n");
+ 	saved = *end_of_object_name;
+ 	*end_of_object_name = '\0';
+ 	status = get_sha1(bol, commit_sha1);
+ 	*end_of_object_name = saved;
+ 
+ 	/*
+ 	 * Verify that the action matches up with the one in
+ 	 * opts; we don't support arbitrary instructions
+ 	 */
+ 	if (action != opts->action) {
+ 		const char *action_str;
+ 		action_str = action == REPLAY_REVERT ? "revert" : "cherry-pick";
+ 		error(_("Cannot %s during a %s"), action_str, action_name(opts));
+ 		return NULL;
+ 	}
+ 
+ 	if (status < 0)
+ 		return NULL;
+ 
+ 	return lookup_commit_reference(commit_sha1);
+ }
+ 
+ static int parse_insn_buffer(char *buf, struct commit_list **todo_list,
+ 			struct replay_opts *opts)
+ {
+ 	struct commit_list **next = todo_list;
+ 	struct commit *commit;
+ 	char *p = buf;
+ 	int i;
+ 
+ 	for (i = 1; *p; i++) {
+ 		char *eol = strchrnul(p, '\n');
+ 		commit = parse_insn_line(p, eol, opts);
+ 		if (!commit)
+ 			return error(_("Could not parse line %d."), i);
+ 		next = commit_list_append(commit, next);
+ 		p = *eol ? eol + 1 : eol;
+ 	}
+ 	if (!*todo_list)
+ 		return error(_("No commits parsed."));
+ 	return 0;
+ }
+ 
+ static void read_populate_todo(struct commit_list **todo_list,
+ 			struct replay_opts *opts)
+ {
+ 	const char *todo_file = git_path(SEQ_TODO_FILE);
+ 	struct strbuf buf = STRBUF_INIT;
+ 	int fd, res;
+ 
+ 	fd = open(todo_file, O_RDONLY);
+ 	if (fd < 0)
+ 		die_errno(_("Could not open %s"), todo_file);
+ 	if (strbuf_read(&buf, fd, 0) < 0) {
+ 		close(fd);
+ 		strbuf_release(&buf);
+ 		die(_("Could not read %s."), todo_file);
+ 	}
+ 	close(fd);
+ 
+ 	res = parse_insn_buffer(buf.buf, todo_list, opts);
+ 	strbuf_release(&buf);
+ 	if (res)
+ 		die(_("Unusable instruction sheet: %s"), todo_file);
+ }
+ 
+ static int populate_opts_cb(const char *key, const char *value, void *data)
+ {
+ 	struct replay_opts *opts = data;
+ 	int error_flag = 1;
+ 
+ 	if (!value)
+ 		error_flag = 0;
+ 	else if (!strcmp(key, "options.no-commit"))
+ 		opts->no_commit = git_config_bool_or_int(key, value, &error_flag);
+ 	else if (!strcmp(key, "options.edit"))
+ 		opts->edit = git_config_bool_or_int(key, value, &error_flag);
+ 	else if (!strcmp(key, "options.signoff"))
+ 		opts->signoff = git_config_bool_or_int(key, value, &error_flag);
+ 	else if (!strcmp(key, "options.record-origin"))
+ 		opts->record_origin = git_config_bool_or_int(key, value, &error_flag);
+ 	else if (!strcmp(key, "options.allow-ff"))
+ 		opts->allow_ff = git_config_bool_or_int(key, value, &error_flag);
+ 	else if (!strcmp(key, "options.mainline"))
+ 		opts->mainline = git_config_int(key, value);
+ 	else if (!strcmp(key, "options.strategy"))
+ 		git_config_string(&opts->strategy, key, value);
+ 	else if (!strcmp(key, "options.strategy-option")) {
+ 		ALLOC_GROW(opts->xopts, opts->xopts_nr + 1, opts->xopts_alloc);
+ 		opts->xopts[opts->xopts_nr++] = xstrdup(value);
+ 	} else
+ 		return error(_("Invalid key: %s"), key);
+ 
+ 	if (!error_flag)
+ 		return error(_("Invalid value for %s: %s"), key, value);
+ 
+ 	return 0;
+ }
+ 
+ static void read_populate_opts(struct replay_opts **opts_ptr)
+ {
+ 	const char *opts_file = git_path(SEQ_OPTS_FILE);
+ 
+ 	if (!file_exists(opts_file))
+ 		return;
+ 	if (git_config_from_file(populate_opts_cb, opts_file, *opts_ptr) < 0)
+ 		die(_("Malformed options sheet: %s"), opts_file);
+ }
+ 
+ static void walk_revs_populate_todo(struct commit_list **todo_list,
+ 				struct replay_opts *opts)
+ {
+ 	struct commit *commit;
+ 	struct commit_list **next;
+ 
+ 	prepare_revs(opts);
+ 
+ 	next = todo_list;
+ 	while ((commit = get_revision(opts->revs)))
+ 		next = commit_list_append(commit, next);
+ }
+ 
+ static int create_seq_dir(void)
+ {
+ 	const char *seq_dir = git_path(SEQ_DIR);
+ 
+ 	if (file_exists(seq_dir)) {
+ 		error(_("a cherry-pick or revert is already in progress"));
+ 		advise(_("try \"git cherry-pick (--continue | --quit | --abort)\""));
+ 		return -1;
+ 	}
+ 	else if (mkdir(seq_dir, 0777) < 0)
+ 		die_errno(_("Could not create sequencer directory %s"), seq_dir);
+ 	return 0;
+ }
+ 
+ static void save_head(const char *head)
+ {
+ 	const char *head_file = git_path(SEQ_HEAD_FILE);
+ 	static struct lock_file head_lock;
+ 	struct strbuf buf = STRBUF_INIT;
+ 	int fd;
+ 
+ 	fd = hold_lock_file_for_update(&head_lock, head_file, LOCK_DIE_ON_ERROR);
+ 	strbuf_addf(&buf, "%s\n", head);
+ 	if (write_in_full(fd, buf.buf, buf.len) < 0)
+ 		die_errno(_("Could not write to %s"), head_file);
+ 	if (commit_lock_file(&head_lock) < 0)
+ 		die(_("Error wrapping up %s."), head_file);
+ }
+ 
+ static int reset_for_rollback(const unsigned char *sha1)
+ {
+ 	const char *argv[4];	/* reset --merge <arg> + NULL */
+ 	argv[0] = "reset";
+ 	argv[1] = "--merge";
+ 	argv[2] = sha1_to_hex(sha1);
+ 	argv[3] = NULL;
+ 	return run_command_v_opt(argv, RUN_GIT_CMD);
+ }
+ 
+ static int rollback_single_pick(void)
+ {
+ 	unsigned char head_sha1[20];
+ 
+ 	if (!file_exists(git_path("CHERRY_PICK_HEAD")) &&
+ 	    !file_exists(git_path("REVERT_HEAD")))
+ 		return error(_("no cherry-pick or revert in progress"));
+ 	if (read_ref_full("HEAD", head_sha1, 0, NULL))
+ 		return error(_("cannot resolve HEAD"));
+ 	if (is_null_sha1(head_sha1))
+ 		return error(_("cannot abort from a branch yet to be born"));
+ 	return reset_for_rollback(head_sha1);
+ }
+ 
+ static int sequencer_rollback(struct replay_opts *opts)
+ {
+ 	const char *filename;
+ 	FILE *f;
+ 	unsigned char sha1[20];
+ 	struct strbuf buf = STRBUF_INIT;
+ 
+ 	filename = git_path(SEQ_HEAD_FILE);
+ 	f = fopen(filename, "r");
+ 	if (!f && errno == ENOENT) {
+ 		/*
+ 		 * There is no multiple-cherry-pick in progress.
+ 		 * If CHERRY_PICK_HEAD or REVERT_HEAD indicates
+ 		 * a single-cherry-pick in progress, abort that.
+ 		 */
+ 		return rollback_single_pick();
+ 	}
+ 	if (!f)
+ 		return error(_("cannot open %s: %s"), filename,
+ 						strerror(errno));
+ 	if (strbuf_getline(&buf, f, '\n')) {
+ 		error(_("cannot read %s: %s"), filename, ferror(f) ?
+ 			strerror(errno) : _("unexpected end of file"));
+ 		fclose(f);
+ 		goto fail;
+ 	}
+ 	fclose(f);
+ 	if (get_sha1_hex(buf.buf, sha1) || buf.buf[40] != '\0') {
+ 		error(_("stored pre-cherry-pick HEAD file '%s' is corrupt"),
+ 			filename);
+ 		goto fail;
+ 	}
+ 	if (reset_for_rollback(sha1))
+ 		goto fail;
+ 	remove_sequencer_state();
+ 	strbuf_release(&buf);
+ 	return 0;
+ fail:
+ 	strbuf_release(&buf);
+ 	return -1;
+ }
+ 
+ static void save_todo(struct commit_list *todo_list, struct replay_opts *opts)
+ {
+ 	const char *todo_file = git_path(SEQ_TODO_FILE);
+ 	static struct lock_file todo_lock;
+ 	struct strbuf buf = STRBUF_INIT;
+ 	int fd;
+ 
+ 	fd = hold_lock_file_for_update(&todo_lock, todo_file, LOCK_DIE_ON_ERROR);
+ 	if (format_todo(&buf, todo_list, opts) < 0)
+ 		die(_("Could not format %s."), todo_file);
+ 	if (write_in_full(fd, buf.buf, buf.len) < 0) {
+ 		strbuf_release(&buf);
+ 		die_errno(_("Could not write to %s"), todo_file);
+ 	}
+ 	if (commit_lock_file(&todo_lock) < 0) {
+ 		strbuf_release(&buf);
+ 		die(_("Error wrapping up %s."), todo_file);
+ 	}
+ 	strbuf_release(&buf);
+ }
+ 
+ static void save_opts(struct replay_opts *opts)
+ {
+ 	const char *opts_file = git_path(SEQ_OPTS_FILE);
+ 
+ 	if (opts->no_commit)
+ 		git_config_set_in_file(opts_file, "options.no-commit", "true");
+ 	if (opts->edit)
+ 		git_config_set_in_file(opts_file, "options.edit", "true");
+ 	if (opts->signoff)
+ 		git_config_set_in_file(opts_file, "options.signoff", "true");
+ 	if (opts->record_origin)
+ 		git_config_set_in_file(opts_file, "options.record-origin", "true");
+ 	if (opts->allow_ff)
+ 		git_config_set_in_file(opts_file, "options.allow-ff", "true");
+ 	if (opts->mainline) {
+ 		struct strbuf buf = STRBUF_INIT;
+ 		strbuf_addf(&buf, "%d", opts->mainline);
+ 		git_config_set_in_file(opts_file, "options.mainline", buf.buf);
+ 		strbuf_release(&buf);
+ 	}
+ 	if (opts->strategy)
+ 		git_config_set_in_file(opts_file, "options.strategy", opts->strategy);
+ 	if (opts->xopts) {
+ 		int i;
+ 		for (i = 0; i < opts->xopts_nr; i++)
+ 			git_config_set_multivar_in_file(opts_file,
+ 							"options.strategy-option",
+ 							opts->xopts[i], "^$", 0);
+ 	}
+ }
+ 
+ static int pick_commits(struct commit_list *todo_list, struct replay_opts *opts)
+ {
+ 	struct commit_list *cur;
+ 	int res;
+ 
+ 	setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
+ 	if (opts->allow_ff)
+ 		assert(!(opts->signoff || opts->no_commit ||
+ 				opts->record_origin || opts->edit));
+ 	read_and_refresh_cache(opts);
+ 
+ 	for (cur = todo_list; cur; cur = cur->next) {
+ 		save_todo(cur, opts);
+ 		res = do_pick_commit(cur->item, opts);
+ 		if (res)
+ 			return res;
+ 	}
+ 
+ 	/*
+ 	 * Sequence of picks finished successfully; cleanup by
+ 	 * removing the .git/sequencer directory
+ 	 */
+ 	remove_sequencer_state();
+ 	return 0;
+ }
+ 
+ static int continue_single_pick(void)
+ {
+ 	const char *argv[] = { "commit", NULL };
+ 
+ 	if (!file_exists(git_path("CHERRY_PICK_HEAD")) &&
+ 	    !file_exists(git_path("REVERT_HEAD")))
+ 		return error(_("no cherry-pick or revert in progress"));
+ 	return run_command_v_opt(argv, RUN_GIT_CMD);
+ }
+ 
+ static int sequencer_continue(struct replay_opts *opts)
+ {
+ 	struct commit_list *todo_list = NULL;
+ 
+ 	if (!file_exists(git_path(SEQ_TODO_FILE)))
+ 		return continue_single_pick();
+ 	read_populate_opts(&opts);
+ 	read_populate_todo(&todo_list, opts);
+ 
+ 	/* Verify that the conflict has been resolved */
+ 	if (file_exists(git_path("CHERRY_PICK_HEAD")) ||
+ 	    file_exists(git_path("REVERT_HEAD"))) {
+ 		int ret = continue_single_pick();
+ 		if (ret)
+ 			return ret;
+ 	}
+ 	if (index_differs_from("HEAD", 0))
+ 		return error_dirty_index(opts);
+ 	todo_list = todo_list->next;
+ 	return pick_commits(todo_list, opts);
+ }
+ 
+ static int single_pick(struct commit *cmit, struct replay_opts *opts)
+ {
+ 	setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
+ 	return do_pick_commit(cmit, opts);
+ }
+ 
+ int sequencer_pick_revisions(struct replay_opts *opts)
+ {
+ 	struct commit_list *todo_list = NULL;
+ 	unsigned char sha1[20];
+ 
+ 	if (opts->subcommand == REPLAY_NONE)
+ 		assert(opts->revs);
+ 
+ 	read_and_refresh_cache(opts);
+ 
+ 	/*
+ 	 * Decide what to do depending on the arguments; a fresh
+ 	 * cherry-pick should be handled differently from an existing
+ 	 * one that is being continued
+ 	 */
+ 	if (opts->subcommand == REPLAY_REMOVE_STATE) {
+ 		remove_sequencer_state();
+ 		return 0;
+ 	}
+ 	if (opts->subcommand == REPLAY_ROLLBACK)
+ 		return sequencer_rollback(opts);
+ 	if (opts->subcommand == REPLAY_CONTINUE)
+ 		return sequencer_continue(opts);
+ 
+ 	/*
+ 	 * If we were called as "git cherry-pick <commit>", just
+ 	 * cherry-pick/revert it, set CHERRY_PICK_HEAD /
+ 	 * REVERT_HEAD, and don't touch the sequencer state.
+ 	 * This means it is possible to cherry-pick in the middle
+ 	 * of a cherry-pick sequence.
+ 	 */
+ 	if (opts->revs->cmdline.nr == 1 &&
+ 	    opts->revs->cmdline.rev->whence == REV_CMD_REV &&
+ 	    opts->revs->no_walk &&
+ 	    !opts->revs->cmdline.rev->flags) {
+ 		struct commit *cmit;
+ 		if (prepare_revision_walk(opts->revs))
+ 			die(_("revision walk setup failed"));
+ 		cmit = get_revision(opts->revs);
+ 		if (!cmit || get_revision(opts->revs))
+ 			die("BUG: expected exactly one commit from walk");
+ 		return single_pick(cmit, opts);
+ 	}
+ 
+ 	/*
+ 	 * Start a new cherry-pick/ revert sequence; but
+ 	 * first, make sure that an existing one isn't in
+ 	 * progress
+ 	 */
+ 
+ 	walk_revs_populate_todo(&todo_list, opts);
+ 	if (create_seq_dir() < 0)
+ 		return -1;
+ 	if (get_sha1("HEAD", sha1)) {
+ 		if (opts->action == REPLAY_REVERT)
+ 			return error(_("Can't revert as initial commit"));
+ 		return error(_("Can't cherry-pick into empty head"));
+ 	}
+ 	save_head(sha1_to_hex(sha1));
+ 	save_opts(opts);
+ 	return pick_commits(todo_list, opts);
+ }