refs: change signatures of get_packed_refs() and get_loose_refs()
[gitweb.git] / builtin / revert.c
index 87df70edc33fcc71177b863e6ced870330e505d0..1ea525c10e4c00b66006bf46465ebd490823f25f 100644 (file)
@@ -40,7 +40,12 @@ static const char * const cherry_pick_usage[] = {
 };
 
 enum replay_action { REVERT, CHERRY_PICK };
-enum replay_subcommand { REPLAY_NONE, REPLAY_RESET, REPLAY_CONTINUE };
+enum replay_subcommand {
+       REPLAY_NONE,
+       REPLAY_REMOVE_STATE,
+       REPLAY_CONTINUE,
+       REPLAY_ROLLBACK
+};
 
 struct replay_opts {
        enum replay_action action;
@@ -133,11 +138,13 @@ static void parse_args(int argc, const char **argv, struct replay_opts *opts)
 {
        const char * const * usage_str = revert_or_cherry_pick_usage(opts);
        const char *me = action_name(opts);
-       int reset = 0;
+       int remove_state = 0;
        int contin = 0;
+       int rollback = 0;
        struct option options[] = {
-               OPT_BOOLEAN(0, "reset", &reset, "forget the current operation"),
-               OPT_BOOLEAN(0, "continue", &contin, "continue the current operation"),
+               OPT_BOOLEAN(0, "quit", &remove_state, "end revert or cherry-pick sequence"),
+               OPT_BOOLEAN(0, "continue", &contin, "resume revert or cherry-pick sequence"),
+               OPT_BOOLEAN(0, "abort", &rollback, "cancel revert or cherry-pick sequence"),
                OPT_BOOLEAN('n', "no-commit", &opts->no_commit, "don't automatically commit"),
                OPT_BOOLEAN('e', "edit", &opts->edit, "edit the commit message"),
                OPT_NOOP_NOARG('r', NULL),
@@ -168,25 +175,32 @@ static void parse_args(int argc, const char **argv, struct replay_opts *opts)
 
        /* Check for incompatible subcommands */
        verify_opt_mutually_compatible(me,
-                               "--reset", reset,
+                               "--quit", remove_state,
                                "--continue", contin,
+                               "--abort", rollback,
                                NULL);
 
        /* Set the subcommand */
-       if (reset)
-               opts->subcommand = REPLAY_RESET;
+       if (remove_state)
+               opts->subcommand = REPLAY_REMOVE_STATE;
        else if (contin)
                opts->subcommand = REPLAY_CONTINUE;
+       else if (rollback)
+               opts->subcommand = REPLAY_ROLLBACK;
        else
                opts->subcommand = REPLAY_NONE;
 
        /* Check for incompatible command line arguments */
        if (opts->subcommand != REPLAY_NONE) {
                char *this_operation;
-               if (opts->subcommand == REPLAY_RESET)
-                       this_operation = "--reset";
-               else
+               if (opts->subcommand == REPLAY_REMOVE_STATE)
+                       this_operation = "--quit";
+               else if (opts->subcommand == REPLAY_CONTINUE)
                        this_operation = "--continue";
+               else {
+                       assert(opts->subcommand == REPLAY_ROLLBACK);
+                       this_operation = "--abort";
+               }
 
                verify_opt_compatible(me, this_operation,
                                "--no-commit", opts->no_commit,
@@ -286,19 +300,20 @@ static char *get_encoding(const char *message)
        return NULL;
 }
 
-static void write_cherry_pick_head(struct commit *commit)
+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));
 
-       fd = open(git_path("CHERRY_PICK_HEAD"), O_WRONLY | O_CREAT, 0666);
+       filename = git_path("%s", pseudoref);
+       fd = open(filename, O_WRONLY | O_CREAT, 0666);
        if (fd < 0)
-               die_errno(_("Could not open '%s' for writing"),
-                         git_path("CHERRY_PICK_HEAD"));
+               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'"), git_path("CHERRY_PICK_HEAD"));
+               die_errno(_("Could not write to '%s'"), filename);
        strbuf_release(&buf);
 }
 
@@ -331,7 +346,7 @@ static void write_message(struct strbuf *msgbuf, const char *filename)
        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);
+               die_errno(_("Could not write to %s"), filename);
        strbuf_release(msgbuf);
        if (commit_lock_file(&msg_file) < 0)
                die(_("Error wrapping up %s"), filename);
@@ -593,7 +608,9 @@ static int do_pick_commit(struct commit *commit, struct replay_opts *opts)
         * write it at all.
         */
        if (opts->action == CHERRY_PICK && !opts->no_commit && (res == 0 || res == 1))
-               write_cherry_pick_head(commit);
+               write_cherry_pick_head(commit, "CHERRY_PICK_HEAD");
+       if (opts->action == REVERT && ((opts->no_commit && res == 0) || res == 1))
+               write_cherry_pick_head(commit, "REVERT_HEAD");
 
        if (res) {
                error(opts->action == REVERT
@@ -767,7 +784,7 @@ static void read_populate_todo(struct commit_list **todo_list,
 
        fd = open(todo_file, O_RDONLY);
        if (fd < 0)
-               die_errno(_("Could not open %s."), todo_file);
+               die_errno(_("Could not open %s"), todo_file);
        if (strbuf_read(&buf, fd, 0) < 0) {
                close(fd);
                strbuf_release(&buf);
@@ -842,10 +859,13 @@ static int create_seq_dir(void)
 {
        const char *seq_dir = git_path(SEQ_DIR);
 
-       if (file_exists(seq_dir))
-               return error(_("%s already exists."), 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);
+               die_errno(_("Could not create sequencer directory %s"), seq_dir);
        return 0;
 }
 
@@ -859,11 +879,77 @@ static void save_head(const char *head)
        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);
+               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 (!resolve_ref("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(1);
+       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);
@@ -876,7 +962,7 @@ static void save_todo(struct commit_list *todo_list, struct replay_opts *opts)
                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);
+               die_errno(_("Could not write to %s"), todo_file);
        }
        if (commit_lock_file(&todo_lock) < 0) {
                strbuf_release(&buf);
@@ -964,43 +1050,41 @@ static int pick_revisions(struct replay_opts *opts)
         * cherry-pick should be handled differently from an existing
         * one that is being continued
         */
-       if (opts->subcommand == REPLAY_RESET) {
+       if (opts->subcommand == REPLAY_REMOVE_STATE) {
                remove_sequencer_state(1);
                return 0;
-       } else if (opts->subcommand == REPLAY_CONTINUE) {
+       }
+       if (opts->subcommand == REPLAY_ROLLBACK)
+               return sequencer_rollback(opts);
+       if (opts->subcommand == REPLAY_CONTINUE) {
                if (!file_exists(git_path(SEQ_TODO_FILE)))
-                       goto error;
+                       return error(_("No %s in progress"), action_name(opts));
                read_populate_opts(&opts);
                read_populate_todo(&todo_list, opts);
 
                /* Verify that the conflict has been resolved */
                if (!index_differs_from("HEAD", 0))
                        todo_list = todo_list->next;
-       } else {
-               /*
-                * Start a new cherry-pick/ revert sequence; but
-                * first, make sure that an existing one isn't in
-                * progress
-                */
+               return pick_commits(todo_list, opts);
+       }
 
-               walk_revs_populate_todo(&todo_list, opts);
-               if (create_seq_dir() < 0) {
-                       error(_("A cherry-pick or revert is in progress."));
-                       advise(_("Use --continue to continue the operation"));
-                       advise(_("or --reset to forget about it"));
-                       return -1;
-               }
-               if (get_sha1("HEAD", sha1)) {
-                       if (opts->action == 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);
+       /*
+        * 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 == 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);
-error:
-       return error(_("No %s in progress"), action_name(opts));
 }
 
 int cmd_revert(int argc, const char **argv, const char *prefix)