sequencer: improve config handling
[gitweb.git] / sequencer.c
index 04c9512f57cd9a67aabafbc878b7e856c28f1366..7051b20b76292e3b539875f0dc38108a734d2164 100644 (file)
@@ -1,10 +1,10 @@
 #include "cache.h"
 #include "config.h"
 #include "lockfile.h"
-#include "sequencer.h"
 #include "dir.h"
 #include "object.h"
 #include "commit.h"
+#include "sequencer.h"
 #include "tag.h"
 #include "run-command.h"
 #include "exec_cmd.h"
@@ -21,6 +21,8 @@
 #include "log-tree.h"
 #include "wt-status.h"
 #include "hashmap.h"
+#include "notes-utils.h"
+#include "sigchain.h"
 
 #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
 
@@ -128,6 +130,52 @@ static GIT_PATH_FUNC(rebase_path_onto, "rebase-merge/onto")
 static GIT_PATH_FUNC(rebase_path_autostash, "rebase-merge/autostash")
 static GIT_PATH_FUNC(rebase_path_strategy, "rebase-merge/strategy")
 static GIT_PATH_FUNC(rebase_path_strategy_opts, "rebase-merge/strategy_opts")
+static GIT_PATH_FUNC(rebase_path_allow_rerere_autoupdate, "rebase-merge/allow_rerere_autoupdate")
+
+static int git_sequencer_config(const char *k, const char *v, void *cb)
+{
+       struct replay_opts *opts = cb;
+       int status;
+
+       if (!strcmp(k, "commit.cleanup")) {
+               const char *s;
+
+               status = git_config_string(&s, k, v);
+               if (status)
+                       return status;
+
+               if (!strcmp(s, "verbatim"))
+                       opts->default_msg_cleanup = COMMIT_MSG_CLEANUP_NONE;
+               else if (!strcmp(s, "whitespace"))
+                       opts->default_msg_cleanup = COMMIT_MSG_CLEANUP_SPACE;
+               else if (!strcmp(s, "strip"))
+                       opts->default_msg_cleanup = COMMIT_MSG_CLEANUP_ALL;
+               else if (!strcmp(s, "scissors"))
+                       opts->default_msg_cleanup = COMMIT_MSG_CLEANUP_SPACE;
+               else
+                       warning(_("invalid commit message cleanup mode '%s'"),
+                                 s);
+
+               return status;
+       }
+
+       if (!strcmp(k, "commit.gpgsign")) {
+               opts->gpg_sign = git_config_bool(k, v) ? "" : NULL;
+               return 0;
+       }
+
+       status = git_gpg_config(k, v, NULL);
+       if (status)
+               return status;
+
+       return git_diff_basic_config(k, v, NULL);
+}
+
+void sequencer_init_config(struct replay_opts *opts)
+{
+       opts->default_msg_cleanup = COMMIT_MSG_CLEANUP_NONE;
+       git_config(git_sequencer_config, opts);
+}
 
 static inline int is_rebase_i(const struct replay_opts *opts)
 {
@@ -203,7 +251,7 @@ int sequencer_remove_state(struct replay_opts *opts)
                free(opts->xopts[i]);
        free(opts->xopts);
 
-       strbuf_addf(&dir, "%s", get_dir(opts));
+       strbuf_addstr(&dir, get_dir(opts));
        remove_dir_recursively(&dir, 0);
        strbuf_release(&dir);
 
@@ -392,7 +440,7 @@ static int fast_forward_to(const struct object_id *to, const struct object_id *f
        transaction = ref_transaction_begin(&err);
        if (!transaction ||
            ref_transaction_update(transaction, "HEAD",
-                                  to->hash, unborn ? null_sha1 : from->hash,
+                                  to, unborn ? &null_oid : from,
                                   0, sb.buf, &err) ||
            ref_transaction_commit(transaction, &err)) {
                ref_transaction_free(transaction);
@@ -474,9 +522,6 @@ static int do_recursive_merge(struct commit *base, struct commit *next,
                        _(action_name(opts)));
        rollback_lock_file(&index_lock);
 
-       if (opts->signoff)
-               append_signoff(msgbuf, 0, 0);
-
        if (!clean)
                append_conflicts_hint(msgbuf);
 
@@ -488,7 +533,7 @@ static int is_index_unchanged(void)
        struct object_id head_oid;
        struct commit *head_commit;
 
-       if (!resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, head_oid.hash, NULL))
+       if (!resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, &head_oid, NULL))
                return error(_("could not resolve HEAD commit\n"));
 
        head_commit = lookup_commit(&head_oid);
@@ -592,6 +637,18 @@ static int read_env_script(struct argv_array *env)
        return 0;
 }
 
+static char *get_author(const char *message)
+{
+       size_t len;
+       const char *a;
+
+       a = find_commit_header(message, "author", &len);
+       if (a)
+               return xmemdupz(a, len);
+
+       return NULL;
+}
+
 static const char staged_changes_advice[] =
 N_("you have staged changes in your working tree\n"
 "If these changes are meant to be squashed into the previous commit, run:\n"
@@ -654,8 +711,6 @@ static int run_git_commit(const char *defmsg, struct replay_opts *opts,
                argv_array_push(&cmd.args, "--amend");
        if (opts->gpg_sign)
                argv_array_pushf(&cmd.args, "-S%s", opts->gpg_sign);
-       if (opts->signoff)
-               argv_array_push(&cmd.args, "-s");
        if (defmsg)
                argv_array_pushl(&cmd.args, "-F", defmsg, NULL);
        if ((flags & CLEANUP_MSG))
@@ -690,9 +745,423 @@ static int run_git_commit(const char *defmsg, struct replay_opts *opts,
        return run_command(&cmd);
 }
 
+static int rest_is_empty(const struct strbuf *sb, int start)
+{
+       int i, eol;
+       const char *nl;
+
+       /* Check if the rest is just whitespace and Signed-off-by's. */
+       for (i = start; i < sb->len; i++) {
+               nl = memchr(sb->buf + i, '\n', sb->len - i);
+               if (nl)
+                       eol = nl - sb->buf;
+               else
+                       eol = sb->len;
+
+               if (strlen(sign_off_header) <= eol - i &&
+                   starts_with(sb->buf + i, sign_off_header)) {
+                       i = eol;
+                       continue;
+               }
+               while (i < eol)
+                       if (!isspace(sb->buf[i++]))
+                               return 0;
+       }
+
+       return 1;
+}
+
+/*
+ * Find out if the message in the strbuf contains only whitespace and
+ * Signed-off-by lines.
+ */
+int message_is_empty(const struct strbuf *sb,
+                    enum commit_msg_cleanup_mode cleanup_mode)
+{
+       if (cleanup_mode == COMMIT_MSG_CLEANUP_NONE && sb->len)
+               return 0;
+       return rest_is_empty(sb, 0);
+}
+
+/*
+ * See if the user edited the message in the editor or left what
+ * was in the template intact
+ */
+int template_untouched(const struct strbuf *sb, const char *template_file,
+                      enum commit_msg_cleanup_mode cleanup_mode)
+{
+       struct strbuf tmpl = STRBUF_INIT;
+       const char *start;
+
+       if (cleanup_mode == COMMIT_MSG_CLEANUP_NONE && sb->len)
+               return 0;
+
+       if (!template_file || strbuf_read_file(&tmpl, template_file, 0) <= 0)
+               return 0;
+
+       strbuf_stripspace(&tmpl, cleanup_mode == COMMIT_MSG_CLEANUP_ALL);
+       if (!skip_prefix(sb->buf, tmpl.buf, &start))
+               start = sb->buf;
+       strbuf_release(&tmpl);
+       return rest_is_empty(sb, start - sb->buf);
+}
+
+int update_head_with_reflog(const struct commit *old_head,
+                           const struct object_id *new_head,
+                           const char *action, const struct strbuf *msg,
+                           struct strbuf *err)
+{
+       struct ref_transaction *transaction;
+       struct strbuf sb = STRBUF_INIT;
+       const char *nl;
+       int ret = 0;
+
+       if (action) {
+               strbuf_addstr(&sb, action);
+               strbuf_addstr(&sb, ": ");
+       }
+
+       nl = strchr(msg->buf, '\n');
+       if (nl) {
+               strbuf_add(&sb, msg->buf, nl + 1 - msg->buf);
+       } else {
+               strbuf_addbuf(&sb, msg);
+               strbuf_addch(&sb, '\n');
+       }
+
+       transaction = ref_transaction_begin(err);
+       if (!transaction ||
+           ref_transaction_update(transaction, "HEAD", new_head,
+                                  old_head ? &old_head->object.oid : &null_oid,
+                                  0, sb.buf, err) ||
+           ref_transaction_commit(transaction, err)) {
+               ret = -1;
+       }
+       ref_transaction_free(transaction);
+       strbuf_release(&sb);
+
+       return ret;
+}
+
+static int run_rewrite_hook(const struct object_id *oldoid,
+                           const struct object_id *newoid)
+{
+       struct child_process proc = CHILD_PROCESS_INIT;
+       const char *argv[3];
+       int code;
+       struct strbuf sb = STRBUF_INIT;
+
+       argv[0] = find_hook("post-rewrite");
+       if (!argv[0])
+               return 0;
+
+       argv[1] = "amend";
+       argv[2] = NULL;
+
+       proc.argv = argv;
+       proc.in = -1;
+       proc.stdout_to_stderr = 1;
+
+       code = start_command(&proc);
+       if (code)
+               return code;
+       strbuf_addf(&sb, "%s %s\n", oid_to_hex(oldoid), oid_to_hex(newoid));
+       sigchain_push(SIGPIPE, SIG_IGN);
+       write_in_full(proc.in, sb.buf, sb.len);
+       close(proc.in);
+       strbuf_release(&sb);
+       sigchain_pop(SIGPIPE);
+       return finish_command(&proc);
+}
+
+void commit_post_rewrite(const struct commit *old_head,
+                        const struct object_id *new_head)
+{
+       struct notes_rewrite_cfg *cfg;
+
+       cfg = init_copy_notes_for_rewrite("amend");
+       if (cfg) {
+               /* we are amending, so old_head is not NULL */
+               copy_note_for_rewrite(cfg, &old_head->object.oid, new_head);
+               finish_copy_notes_for_rewrite(cfg, "Notes added by 'git commit --amend'");
+       }
+       run_rewrite_hook(&old_head->object.oid, new_head);
+}
+
+static const char implicit_ident_advice_noconfig[] =
+N_("Your name and email address were configured automatically based\n"
+"on your username and hostname. Please check that they are accurate.\n"
+"You can suppress this message by setting them explicitly. Run the\n"
+"following command and follow the instructions in your editor to edit\n"
+"your configuration file:\n"
+"\n"
+"    git config --global --edit\n"
+"\n"
+"After doing this, you may fix the identity used for this commit with:\n"
+"\n"
+"    git commit --amend --reset-author\n");
+
+static const char implicit_ident_advice_config[] =
+N_("Your name and email address were configured automatically based\n"
+"on your username and hostname. Please check that they are accurate.\n"
+"You can suppress this message by setting them explicitly:\n"
+"\n"
+"    git config --global user.name \"Your Name\"\n"
+"    git config --global user.email you@example.com\n"
+"\n"
+"After doing this, you may fix the identity used for this commit with:\n"
+"\n"
+"    git commit --amend --reset-author\n");
+
+static const char *implicit_ident_advice(void)
+{
+       char *user_config = expand_user_path("~/.gitconfig", 0);
+       char *xdg_config = xdg_config_home("config");
+       int config_exists = file_exists(user_config) || file_exists(xdg_config);
+
+       free(user_config);
+       free(xdg_config);
+
+       if (config_exists)
+               return _(implicit_ident_advice_config);
+       else
+               return _(implicit_ident_advice_noconfig);
+
+}
+
+void print_commit_summary(const char *prefix, const struct object_id *oid,
+                         unsigned int flags)
+{
+       struct rev_info rev;
+       struct commit *commit;
+       struct strbuf format = STRBUF_INIT;
+       const char *head;
+       struct pretty_print_context pctx = {0};
+       struct strbuf author_ident = STRBUF_INIT;
+       struct strbuf committer_ident = STRBUF_INIT;
+
+       commit = lookup_commit(oid);
+       if (!commit)
+               die(_("couldn't look up newly created commit"));
+       if (parse_commit(commit))
+               die(_("could not parse newly created commit"));
+
+       strbuf_addstr(&format, "format:%h] %s");
+
+       format_commit_message(commit, "%an <%ae>", &author_ident, &pctx);
+       format_commit_message(commit, "%cn <%ce>", &committer_ident, &pctx);
+       if (strbuf_cmp(&author_ident, &committer_ident)) {
+               strbuf_addstr(&format, "\n Author: ");
+               strbuf_addbuf_percentquote(&format, &author_ident);
+       }
+       if (flags & SUMMARY_SHOW_AUTHOR_DATE) {
+               struct strbuf date = STRBUF_INIT;
+
+               format_commit_message(commit, "%ad", &date, &pctx);
+               strbuf_addstr(&format, "\n Date: ");
+               strbuf_addbuf_percentquote(&format, &date);
+               strbuf_release(&date);
+       }
+       if (!committer_ident_sufficiently_given()) {
+               strbuf_addstr(&format, "\n Committer: ");
+               strbuf_addbuf_percentquote(&format, &committer_ident);
+               if (advice_implicit_identity) {
+                       strbuf_addch(&format, '\n');
+                       strbuf_addstr(&format, implicit_ident_advice());
+               }
+       }
+       strbuf_release(&author_ident);
+       strbuf_release(&committer_ident);
+
+       init_revisions(&rev, prefix);
+       setup_revisions(0, NULL, &rev, NULL);
+
+       rev.diff = 1;
+       rev.diffopt.output_format =
+               DIFF_FORMAT_SHORTSTAT | DIFF_FORMAT_SUMMARY;
+
+       rev.verbose_header = 1;
+       rev.show_root_diff = 1;
+       get_commit_format(format.buf, &rev);
+       rev.always_show_header = 0;
+       rev.diffopt.detect_rename = 1;
+       rev.diffopt.break_opt = 0;
+       diff_setup_done(&rev.diffopt);
+
+       head = resolve_ref_unsafe("HEAD", 0, NULL, NULL);
+       if (!head)
+               die_errno(_("unable to resolve HEAD after creating commit"));
+       if (!strcmp(head, "HEAD"))
+               head = _("detached HEAD");
+       else
+               skip_prefix(head, "refs/heads/", &head);
+       printf("[%s%s ", head, (flags & SUMMARY_INITIAL_COMMIT) ?
+                                               _(" (root-commit)") : "");
+
+       if (!log_tree_commit(&rev, commit)) {
+               rev.always_show_header = 1;
+               rev.use_terminator = 1;
+               log_tree_commit(&rev, commit);
+       }
+
+       strbuf_release(&format);
+}
+
+static int parse_head(struct commit **head)
+{
+       struct commit *current_head;
+       struct object_id oid;
+
+       if (get_oid("HEAD", &oid)) {
+               current_head = NULL;
+       } else {
+               current_head = lookup_commit_reference(&oid);
+               if (!current_head)
+                       return error(_("could not parse HEAD"));
+               if (oidcmp(&oid, &current_head->object.oid)) {
+                       warning(_("HEAD %s is not a commit!"),
+                               oid_to_hex(&oid));
+               }
+               if (parse_commit(current_head))
+                       return error(_("could not parse HEAD commit"));
+       }
+       *head = current_head;
+
+       return 0;
+}
+
+/*
+ * Try to commit without forking 'git commit'. In some cases we need
+ * to run 'git commit' to display an error message
+ *
+ * Returns:
+ *  -1 - error unable to commit
+ *   0 - success
+ *   1 - run 'git commit'
+ */
+static int try_to_commit(struct strbuf *msg, const char *author,
+                        struct replay_opts *opts, unsigned int flags,
+                        struct object_id *oid)
+{
+       struct object_id tree;
+       struct commit *current_head;
+       struct commit_list *parents = NULL;
+       struct commit_extra_header *extra = NULL;
+       struct strbuf err = STRBUF_INIT;
+       struct strbuf amend_msg = STRBUF_INIT;
+       char *amend_author = NULL;
+       enum commit_msg_cleanup_mode cleanup;
+       int res = 0;
+
+       if (parse_head(&current_head))
+               return -1;
+
+       if (flags & AMEND_MSG) {
+               const char *exclude_gpgsig[] = { "gpgsig", NULL };
+               const char *out_enc = get_commit_output_encoding();
+               const char *message = logmsg_reencode(current_head, NULL,
+                                                     out_enc);
+
+               if (!msg) {
+                       const char *orig_message = NULL;
+
+                       find_commit_subject(message, &orig_message);
+                       msg = &amend_msg;
+                       strbuf_addstr(msg, orig_message);
+               }
+               author = amend_author = get_author(message);
+               unuse_commit_buffer(current_head, message);
+               if (!author) {
+                       res = error(_("unable to parse commit author"));
+                       goto out;
+               }
+               parents = copy_commit_list(current_head->parents);
+               extra = read_commit_extra_headers(current_head, exclude_gpgsig);
+       } else if (current_head) {
+               commit_list_insert(current_head, &parents);
+       }
+
+       cleanup = (flags & CLEANUP_MSG) ? COMMIT_MSG_CLEANUP_ALL :
+                                         opts->default_msg_cleanup;
+
+       if (cleanup != COMMIT_MSG_CLEANUP_NONE)
+               strbuf_stripspace(msg, cleanup == COMMIT_MSG_CLEANUP_ALL);
+       if (!opts->allow_empty_message && message_is_empty(msg, cleanup)) {
+               res = 1; /* run 'git commit' to display error message */
+               goto out;
+       }
+
+       if (write_cache_as_tree(tree.hash, 0, NULL)) {
+               res = error(_("git write-tree failed to write a tree"));
+               goto out;
+       }
+
+       if (!(flags & ALLOW_EMPTY) && !oidcmp(current_head ?
+                                             &current_head->tree->object.oid :
+                                             &empty_tree_oid, &tree)) {
+               res = 1; /* run 'git commit' to display error message */
+               goto out;
+       }
+
+       if (commit_tree_extended(msg->buf, msg->len, tree.hash, parents,
+                                oid->hash, author, opts->gpg_sign, extra)) {
+               res = error(_("failed to write commit object"));
+               goto out;
+       }
+
+       if (update_head_with_reflog(current_head, oid,
+                                   getenv("GIT_REFLOG_ACTION"), msg, &err)) {
+               res = error("%s", err.buf);
+               goto out;
+       }
+
+       if (flags & AMEND_MSG)
+               commit_post_rewrite(current_head, oid);
+
+out:
+       free_commit_extra_headers(extra);
+       strbuf_release(&err);
+       strbuf_release(&amend_msg);
+       free(amend_author);
+
+       return res;
+}
+
+static int do_commit(const char *msg_file, const char *author,
+                    struct replay_opts *opts, unsigned int flags)
+{
+       int res = 1;
+
+       if (!(flags & EDIT_MSG) && !(flags & VERIFY_MSG)) {
+               struct object_id oid;
+               struct strbuf sb = STRBUF_INIT;
+
+               if (msg_file && strbuf_read_file(&sb, msg_file, 2048) < 0)
+                       return error_errno(_("unable to read commit message "
+                                            "from '%s'"),
+                                          msg_file);
+
+               res = try_to_commit(msg_file ? &sb : NULL, author, opts, flags,
+                                   &oid);
+               strbuf_release(&sb);
+               if (!res) {
+                       unlink(git_path_cherry_pick_head());
+                       unlink(git_path_merge_msg());
+                       if (!is_rebase_i(opts))
+                               print_commit_summary(NULL, &oid,
+                                               SUMMARY_SHOW_AUTHOR_DATE);
+                       return res;
+               }
+       }
+       if (res == 1)
+               return run_git_commit(msg_file, opts, flags);
+
+       return res;
+}
+
 static int is_original_commit_empty(struct commit *commit)
 {
-       const unsigned char *ptree_sha1;
+       const struct object_id *ptree_oid;
 
        if (parse_commit(commit))
                return error(_("could not parse commit %s\n"),
@@ -702,12 +1171,12 @@ static int is_original_commit_empty(struct commit *commit)
                if (parse_commit(parent))
                        return error(_("could not parse parent commit %s\n"),
                                oid_to_hex(&parent->object.oid));
-               ptree_sha1 = parent->tree->object.oid.hash;
+               ptree_oid = &parent->tree->object.oid;
        } else {
-               ptree_sha1 = EMPTY_TREE_SHA1_BIN; /* commit is root */
+               ptree_oid = &empty_tree_oid; /* commit is root */
        }
 
-       return !hashcmp(ptree_sha1, commit->tree->object.oid.hash);
+       return !oidcmp(ptree_oid, &commit->tree->object.oid);
 }
 
 /*
@@ -897,18 +1366,18 @@ static int update_squash_messages(enum todo_command command,
 
 static void flush_rewritten_pending(void) {
        struct strbuf buf = STRBUF_INIT;
-       unsigned char newsha1[20];
+       struct object_id newoid;
        FILE *out;
 
-       if (strbuf_read_file(&buf, rebase_path_rewritten_pending(), 82) > 0 &&
-           !get_sha1("HEAD", newsha1) &&
+       if (strbuf_read_file(&buf, rebase_path_rewritten_pending(), (GIT_MAX_HEXSZ + 1) * 2) > 0 &&
+           !get_oid("HEAD", &newoid) &&
            (out = fopen_or_warn(rebase_path_rewritten_list(), "a"))) {
                char *bol = buf.buf, *eol;
 
                while (*bol) {
                        eol = strchrnul(bol, '\n');
                        fprintf(out, "%.*s %s\n", (int)(eol - bol),
-                                       bol, sha1_to_hex(newsha1));
+                                       bol, oid_to_hex(&newoid));
                        if (!*eol)
                                break;
                        bol = eol + 1;
@@ -941,6 +1410,7 @@ static int do_pick_commit(enum todo_command command, struct commit *commit,
        struct object_id head;
        struct commit *base, *next, *parent;
        const char *base_label, *next_label;
+       char *author = NULL;
        struct commit_message msg = { NULL, NULL, NULL, NULL };
        struct strbuf msgbuf = STRBUF_INIT;
        int res, unborn = 0, allow;
@@ -958,7 +1428,8 @@ static int do_pick_commit(enum todo_command command, struct commit *commit,
                unborn = get_oid("HEAD", &head);
                if (unborn)
                        oidcpy(&head, &empty_tree_oid);
-               if (index_differs_from(unborn ? EMPTY_TREE_SHA1_HEX : "HEAD", 0, 0))
+               if (index_differs_from(unborn ? EMPTY_TREE_SHA1_HEX : "HEAD",
+                                      NULL, 0))
                        return error_dirty_index(opts);
        }
        discard_cache();
@@ -1056,6 +1527,8 @@ static int do_pick_commit(enum todo_command command, struct commit *commit,
                        strbuf_addstr(&msgbuf, oid_to_hex(&commit->object.oid));
                        strbuf_addstr(&msgbuf, ")\n");
                }
+               if (!is_fixup(command))
+                       author = get_author(msg.message);
        }
 
        if (command == TODO_REWORD)
@@ -1081,6 +1554,9 @@ static int do_pick_commit(enum todo_command command, struct commit *commit,
                }
        }
 
+       if (opts->signoff)
+               append_signoff(&msgbuf, 0, 0);
+
        if (is_rebase_i(opts) && write_author_script(msg.message) < 0)
                res = -1;
        else if (!opts->strategy || !strcmp(opts->strategy, "recursive") || command == TODO_REVERT) {
@@ -1114,11 +1590,11 @@ static int do_pick_commit(enum todo_command command, struct commit *commit,
         * write it at all.
         */
        if (command == TODO_PICK && !opts->no_commit && (res == 0 || res == 1) &&
-           update_ref(NULL, "CHERRY_PICK_HEAD", commit->object.oid.hash, NULL,
+           update_ref(NULL, "CHERRY_PICK_HEAD", &commit->object.oid, NULL,
                       REF_NODEREF, UPDATE_REFS_MSG_ON_ERR))
                res = -1;
        if (command == TODO_REVERT && ((opts->no_commit && res == 0) || res == 1) &&
-           update_ref(NULL, "REVERT_HEAD", commit->object.oid.hash, NULL,
+           update_ref(NULL, "REVERT_HEAD", &commit->object.oid, NULL,
                       REF_NODEREF, UPDATE_REFS_MSG_ON_ERR))
                res = -1;
 
@@ -1138,9 +1614,13 @@ static int do_pick_commit(enum todo_command command, struct commit *commit,
                goto leave;
        } else if (allow)
                flags |= ALLOW_EMPTY;
-       if (!opts->no_commit)
+       if (!opts->no_commit) {
 fast_forward_edit:
-               res = run_git_commit(msg_file, opts, flags);
+               if (author || command == TODO_REVERT || (flags & AMEND_MSG))
+                       res = do_commit(msg_file, author, opts, flags);
+               else
+                       res = error(_("unable to parse commit author"));
+       }
 
        if (!res && final_fixup) {
                unlink(rebase_path_fixup_msg());
@@ -1149,6 +1629,7 @@ static int do_pick_commit(enum todo_command command, struct commit *commit,
 
 leave:
        free_message(commit, &msg);
+       free(author);
        update_abort_safety_file();
 
        return res;
@@ -1183,7 +1664,6 @@ static int read_and_refresh_cache(struct replay_opts *opts)
        refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, NULL, NULL, NULL);
        if (the_index.cache_changed && index_fd >= 0) {
                if (write_locked_index(&the_index, &index_lock, COMMIT_LOCK)) {
-                       rollback_lock_file(&index_lock);
                        return error(_("git %s: failed to refresh the index"),
                                _(action_name(opts)));
                }
@@ -1439,7 +1919,11 @@ static int populate_opts_cb(const char *key, const char *value, void *data)
        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
+       } else if (!strcmp(key, "options.allow-rerere-auto"))
+               opts->allow_rerere_auto =
+                       git_config_bool_or_int(key, value, &error_flag) ?
+                               RERERE_AUTOUPDATE : RERERE_NOAUTOUPDATE;
+       else
                return error(_("invalid key: %s"), key);
 
        if (!error_flag)
@@ -1480,6 +1964,15 @@ static int read_populate_opts(struct replay_opts *opts)
                                free(opts->gpg_sign);
                                opts->gpg_sign = xstrdup(buf.buf + 2);
                        }
+                       strbuf_reset(&buf);
+               }
+
+               if (read_oneliner(&buf, rebase_path_allow_rerere_autoupdate(), 1)) {
+                       if (!strcmp(buf.buf, "--rerere-autoupdate"))
+                               opts->allow_rerere_auto = RERERE_AUTOUPDATE;
+                       else if (!strcmp(buf.buf, "--no-rerere-autoupdate"))
+                               opts->allow_rerere_auto = RERERE_NOAUTOUPDATE;
+                       strbuf_reset(&buf);
                }
 
                if (file_exists(rebase_path_verbose()))
@@ -1552,6 +2045,7 @@ static int save_head(const char *head)
        static struct lock_file head_lock;
        struct strbuf buf = STRBUF_INIT;
        int fd;
+       ssize_t written;
 
        fd = hold_lock_file_for_update(&head_lock, git_path_head_file(), 0);
        if (fd < 0) {
@@ -1559,7 +2053,9 @@ static int save_head(const char *head)
                return error_errno(_("could not lock HEAD"));
        }
        strbuf_addf(&buf, "%s\n", head);
-       if (write_in_full(fd, buf.buf, buf.len) < 0) {
+       written = write_in_full(fd, buf.buf, buf.len);
+       strbuf_release(&buf);
+       if (written < 0) {
                rollback_lock_file(&head_lock);
                return error_errno(_("could not write to '%s'"),
                                   git_path_head_file());
@@ -1595,36 +2091,37 @@ static int rollback_is_safe(void)
        return !oidcmp(&actual_head, &expected_head);
 }
 
-static int reset_for_rollback(const unsigned char *sha1)
+static int reset_for_rollback(const struct object_id *oid)
 {
        const char *argv[4];    /* reset --merge <arg> + NULL */
 
        argv[0] = "reset";
        argv[1] = "--merge";
-       argv[2] = sha1_to_hex(sha1);
+       argv[2] = oid_to_hex(oid);
        argv[3] = NULL;
        return run_command_v_opt(argv, RUN_GIT_CMD);
 }
 
 static int rollback_single_pick(void)
 {
-       unsigned char head_sha1[20];
+       struct object_id head_oid;
 
        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", 0, head_sha1, NULL))
+       if (read_ref_full("HEAD", 0, &head_oid, NULL))
                return error(_("cannot resolve HEAD"));
-       if (is_null_sha1(head_sha1))
+       if (is_null_oid(&head_oid))
                return error(_("cannot abort from a branch yet to be born"));
-       return reset_for_rollback(head_sha1);
+       return reset_for_rollback(&head_oid);
 }
 
 int sequencer_rollback(struct replay_opts *opts)
 {
        FILE *f;
-       unsigned char sha1[20];
+       struct object_id oid;
        struct strbuf buf = STRBUF_INIT;
+       const char *p;
 
        f = fopen(git_path_head_file(), "r");
        if (!f && errno == ENOENT) {
@@ -1644,12 +2141,12 @@ int sequencer_rollback(struct replay_opts *opts)
                goto fail;
        }
        fclose(f);
-       if (get_sha1_hex(buf.buf, sha1) || buf.buf[40] != '\0') {
+       if (parse_oid_hex(buf.buf, &oid, &p) || *p != '\0') {
                error(_("stored pre-cherry-pick HEAD file '%s' is corrupt"),
                        git_path_head_file());
                goto fail;
        }
-       if (is_null_sha1(sha1)) {
+       if (is_null_oid(&oid)) {
                error(_("cannot abort from a branch yet to be born"));
                goto fail;
        }
@@ -1659,7 +2156,7 @@ int sequencer_rollback(struct replay_opts *opts)
                warning(_("You seem to have moved HEAD. "
                          "Not rewinding, check your HEAD!"));
        } else
-       if (reset_for_rollback(sha1))
+       if (reset_for_rollback(&oid))
                goto fail;
        strbuf_release(&buf);
        return sequencer_remove_state(opts);
@@ -1743,6 +2240,10 @@ static int save_opts(struct replay_opts *opts)
                                                        "options.strategy-option",
                                                        opts->xopts[i], "^$", 0);
        }
+       if (opts->allow_rerere_auto)
+               res |= git_config_set_in_file_gently(opts_file, "options.allow-rerere-auto",
+                                                    opts->allow_rerere_auto == RERERE_AUTOUPDATE ?
+                                                    "true" : "false");
        return res;
 }
 
@@ -1789,13 +2290,13 @@ static int make_patch(struct commit *commit, struct replay_opts *opts)
 
 static int intend_to_amend(void)
 {
-       unsigned char head[20];
+       struct object_id head;
        char *p;
 
-       if (get_sha1("HEAD", head))
+       if (get_oid("HEAD", &head))
                return error(_("cannot read HEAD"));
 
-       p = sha1_to_hex(head);
+       p = oid_to_hex(&head);
        return write_message(p, strlen(p), rebase_path_amend(), 1);
 }
 
@@ -1840,12 +2341,15 @@ static int error_failed_squash(struct commit *commit,
 
 static int do_exec(const char *command_line)
 {
+       struct argv_array child_env = ARGV_ARRAY_INIT;
        const char *child_argv[] = { NULL, NULL };
        int dirty, status;
 
        fprintf(stderr, "Executing: %s\n", command_line);
        child_argv[0] = command_line;
-       status = run_command_v_opt(child_argv, RUN_USING_SHELL);
+       argv_array_pushf(&child_env, "GIT_DIR=%s", absolute_path(get_git_dir()));
+       status = run_command_v_opt_cd_env(child_argv, RUN_USING_SHELL, NULL,
+                                         child_env.argv);
 
        /* force re-reading of the cache */
        if (discard_cache() < 0 || read_cache() < 0)
@@ -1875,6 +2379,8 @@ static int do_exec(const char *command_line)
                status = 1;
        }
 
+       argv_array_clear(&child_env);
+
        return status;
 }
 
@@ -2080,10 +2586,10 @@ static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts)
                if (read_oneliner(&head_ref, rebase_path_head_name(), 0) &&
                                starts_with(head_ref.buf, "refs/")) {
                        const char *msg;
-                       unsigned char head[20], orig[20];
+                       struct object_id head, orig;
                        int res;
 
-                       if (get_sha1("HEAD", head)) {
+                       if (get_oid("HEAD", &head)) {
                                res = error(_("cannot read HEAD"));
 cleanup_head_ref:
                                strbuf_release(&head_ref);
@@ -2091,7 +2597,7 @@ static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts)
                                return res;
                        }
                        if (!read_oneliner(&buf, rebase_path_orig_head(), 0) ||
-                                       get_sha1_hex(buf.buf, orig)) {
+                                       get_oid_hex(buf.buf, &orig)) {
                                res = error(_("could not read orig-head"));
                                goto cleanup_head_ref;
                        }
@@ -2102,8 +2608,8 @@ static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts)
                        }
                        msg = reflog_message(opts, "finish", "%s onto %s",
                                head_ref.buf, buf.buf);
-                       if (update_ref(msg, head_ref.buf, head, orig,
-                                       REF_NODEREF, UPDATE_REFS_MSG_ON_ERR)) {
+                       if (update_ref(msg, head_ref.buf, &head, &orig,
+                                      REF_NODEREF, UPDATE_REFS_MSG_ON_ERR)) {
                                res = error(_("could not update %s"),
                                        head_ref.buf);
                                goto cleanup_head_ref;
@@ -2130,8 +2636,8 @@ static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts)
                        log_tree_opt.disable_stdin = 1;
 
                        if (read_oneliner(&buf, rebase_path_orig_head(), 0) &&
-                           !get_sha1(buf.buf, orig.hash) &&
-                           !get_sha1("HEAD", head.hash)) {
+                           !get_oid(buf.buf, &orig) &&
+                           !get_oid("HEAD", &head)) {
                                diff_tree_oid(&orig, &head, "",
                                              &log_tree_opt.diffopt);
                                log_tree_diff_flush(&log_tree_opt);
@@ -2206,16 +2712,16 @@ static int commit_staged_changes(struct replay_opts *opts)
 
        if (file_exists(rebase_path_amend())) {
                struct strbuf rev = STRBUF_INIT;
-               unsigned char head[20], to_amend[20];
+               struct object_id head, to_amend;
 
-               if (get_sha1("HEAD", head))
+               if (get_oid("HEAD", &head))
                        return error(_("cannot amend non-existing commit"));
                if (!read_oneliner(&rev, rebase_path_amend(), 0))
                        return error(_("invalid file: '%s'"), rebase_path_amend());
-               if (get_sha1_hex(rev.buf, to_amend))
+               if (get_oid_hex(rev.buf, &to_amend))
                        return error(_("invalid contents: '%s'"),
                                rebase_path_amend());
-               if (hashcmp(head, to_amend))
+               if (oidcmp(&head, &to_amend))
                        return error(_("\nYou have uncommitted changes in your "
                                       "working tree. Please, commit them\n"
                                       "first and then run 'git rebase "
@@ -2257,7 +2763,7 @@ int sequencer_continue(struct replay_opts *opts)
                        if (res)
                                goto release_todo_list;
                }
-               if (index_differs_from("HEAD", 0, 0)) {
+               if (index_differs_from("HEAD", NULL, 0)) {
                        res = error_dirty_index(opts);
                        goto release_todo_list;
                }
@@ -2267,7 +2773,7 @@ int sequencer_continue(struct replay_opts *opts)
                struct object_id oid;
 
                if (read_oneliner(&buf, rebase_path_stopped_sha(), 1) &&
-                   !get_sha1_committish(buf.buf, oid.hash))
+                   !get_oid_committish(buf.buf, &oid))
                        record_in_rewritten(&oid, peek_command(&todo_list, 0));
                strbuf_release(&buf);
        }