Code

Avoid segfault with 'git branch' when the HEAD is detached
[git.git] / builtin-commit.c
index b0fe69ecad6523dd40f8f5f777a7b81e31eefa3d..46e649cd7ca0a2ede8f010a6d3bf294f81b85d55 100644 (file)
 #include "strbuf.h"
 #include "utf8.h"
 #include "parse-options.h"
-#include "path-list.h"
+#include "string-list.h"
+#include "rerere.h"
 #include "unpack-trees.h"
 
 static const char * const builtin_commit_usage[] = {
-       "git-commit [options] [--] <filepattern>...",
+       "git commit [options] [--] <filepattern>...",
        NULL
 };
 
 static const char * const builtin_status_usage[] = {
-       "git-status [options] [--] <filepattern>...",
+       "git status [options] [--] <filepattern>...",
        NULL
 };
 
@@ -45,10 +46,13 @@ static enum {
        COMMIT_PARTIAL,
 } commit_style;
 
-static char *logfile, *force_author, *template_file;
+static const char *logfile, *force_author;
+static const char *template_file;
 static char *edit_message, *use_message;
+static char *author_name, *author_email, *author_date;
 static int all, edit_flag, also, interactive, only, amend, signoff;
-static int quiet, verbose, untracked_files, no_verify, allow_empty;
+static int quiet, verbose, no_verify, allow_empty;
+static char *untracked_files_arg;
 /*
  * The default commit message cleanup mode will remove the lines
  * beginning with # (shell comments) and leading and trailing
@@ -64,8 +68,8 @@ static enum {
 static char *cleanup_arg;
 
 static int use_editor = 1, initial_commit, in_merge;
-const char *only_include_assumed;
-struct strbuf message;
+static const char *only_include_assumed;
+static struct strbuf message;
 
 static int opt_parse_m(const struct option *opt, const char *arg, int unset)
 {
@@ -74,8 +78,7 @@ static int opt_parse_m(const struct option *opt, const char *arg, int unset)
                strbuf_setlen(buf, 0);
        else {
                strbuf_addstr(buf, arg);
-               strbuf_addch(buf, '\n');
-               strbuf_addch(buf, '\n');
+               strbuf_addstr(buf, "\n\n");
        }
        return 0;
 }
@@ -101,7 +104,7 @@ static struct option builtin_commit_options[] = {
        OPT_BOOLEAN('o', "only", &only, "commit only specified files"),
        OPT_BOOLEAN('n', "no-verify", &no_verify, "bypass pre-commit hook"),
        OPT_BOOLEAN(0, "amend", &amend, "amend previous commit"),
-       OPT_BOOLEAN('u', "untracked-files", &untracked_files, "show all untracked files"),
+       { OPTION_STRING, 'u', "untracked-files", &untracked_files_arg, "mode", "show untracked files, optional modes: all, normal, no. (Default: all)", PARSE_OPT_OPTARG, NULL, (intptr_t)"all" },
        OPT_BOOLEAN(0, "allow-empty", &allow_empty, "ok to record an empty change"),
        OPT_STRING(0, "cleanup", &cleanup_arg, "default", "how to strip spaces and #comments from message"),
 
@@ -146,7 +149,7 @@ static int commit_index_files(void)
  * Take a union of paths in the index and the named tree (typically, "HEAD"),
  * and return the paths that match the given pattern in list.
  */
-static int list_paths(struct path_list *list, const char *with_tree,
+static int list_paths(struct string_list *list, const char *with_tree,
                      const char *prefix, const char **pattern)
 {
        int i;
@@ -163,23 +166,26 @@ static int list_paths(struct path_list *list, const char *with_tree,
                struct cache_entry *ce = active_cache[i];
                if (ce->ce_flags & CE_UPDATE)
                        continue;
-               if (!pathspec_match(pattern, m, ce->name, 0))
+               if (!match_pathspec(pattern, ce->name, ce_namelen(ce), 0, m))
                        continue;
-               path_list_insert(ce->name, list);
+               string_list_insert(ce->name, list);
        }
 
        return report_path_error(m, pattern, prefix ? strlen(prefix) : 0);
 }
 
-static void add_remove_files(struct path_list *list)
+static void add_remove_files(struct string_list *list)
 {
        int i;
        for (i = 0; i < list->nr; i++) {
-               struct path_list_item *p = &(list->items[i]);
-               if (file_exists(p->path))
-                       add_file_to_cache(p->path, 0);
-               else
-                       remove_file_from_cache(p->path);
+               struct stat st;
+               struct string_list_item *p = &(list->items[i]);
+
+               if (!lstat(p->string, &st)) {
+                       if (add_to_cache(p->string, &st, 0))
+                               die("updating files failed");
+               } else
+                       remove_file_from_cache(p->string);
        }
 }
 
@@ -214,23 +220,23 @@ static void create_base_index(void)
 static char *prepare_index(int argc, const char **argv, const char *prefix)
 {
        int fd;
-       struct path_list partial;
+       struct string_list partial;
        const char **pathspec = NULL;
 
        if (interactive) {
                interactive_add(argc, argv, prefix);
-               if (read_cache() < 0)
+               if (read_cache_preload(NULL) < 0)
                        die("index file corrupt");
                commit_style = COMMIT_AS_IS;
                return get_index_file();
        }
 
-       if (read_cache() < 0)
-               die("index file corrupt");
-
        if (*argv)
                pathspec = get_pathspec(prefix, argv);
 
+       if (read_cache_preload(pathspec) < 0)
+               die("index file corrupt");
+
        /*
         * Non partial, non as-is commit.
         *
@@ -245,7 +251,7 @@ static char *prepare_index(int argc, const char **argv, const char *prefix)
         */
        if (all || (also && pathspec && *pathspec)) {
                int fd = hold_locked_index(&index_lock, 1);
-               add_files_to_cache(0, also ? prefix : NULL, pathspec);
+               add_files_to_cache(also ? prefix : NULL, pathspec, 0);
                refresh_cache(REFRESH_QUIET);
                if (write_cache(fd, active_cache, active_nr) ||
                    close_lock_file(&index_lock))
@@ -298,7 +304,7 @@ static char *prepare_index(int argc, const char **argv, const char *prefix)
                die("cannot do a partial commit during a merge.");
 
        memset(&partial, 0, sizeof(partial));
-       partial.strdup_paths = 1;
+       partial.strdup_strings = 1;
        if (list_paths(&partial, initial_commit ? NULL : "HEAD", prefix, pathspec))
                exit(1);
 
@@ -314,7 +320,9 @@ static char *prepare_index(int argc, const char **argv, const char *prefix)
                die("unable to write new_index file");
 
        fd = hold_lock_file_for_update(&false_lock,
-                                      git_path("next-index-%d", getpid()), 1);
+                                      git_path("next-index-%"PRIuMAX,
+                                               (uintmax_t) getpid()),
+                                      LOCK_DIE_ON_ERROR);
 
        create_base_index();
        add_remove_files(&partial);
@@ -343,7 +351,7 @@ static int run_status(FILE *fp, const char *index_file, const char *prefix, int
                s.reference = "HEAD^1";
        }
        s.verbose = verbose;
-       s.untracked = untracked_files;
+       s.untracked = (show_untracked_files == SHOW_ALL_UNTRACKED_FILES);
        s.index_file = index_file;
        s.fp = fp;
        s.nowarn = nowarn;
@@ -353,40 +361,6 @@ static int run_status(FILE *fp, const char *index_file, const char *prefix, int
        return s.commitable;
 }
 
-static int run_hook(const char *index_file, const char *name, ...)
-{
-       struct child_process hook;
-       const char *argv[10], *env[2];
-       char index[PATH_MAX];
-       va_list args;
-       int i;
-
-       va_start(args, name);
-       argv[0] = git_path("hooks/%s", name);
-       i = 0;
-       do {
-               if (++i >= ARRAY_SIZE(argv))
-                       die ("run_hook(): too many arguments");
-               argv[i] = va_arg(args, const char *);
-       } while (argv[i]);
-       va_end(args);
-
-       snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
-       env[0] = index;
-       env[1] = NULL;
-
-       if (access(argv[0], X_OK) < 0)
-               return 0;
-
-       memset(&hook, 0, sizeof(hook));
-       hook.argv = argv;
-       hook.no_stdin = 1;
-       hook.stdout_to_stderr = 1;
-       hook.env = env;
-
-       return run_command(&hook);
-}
-
 static int is_a_merge(const unsigned char *sha1)
 {
        struct commit *commit = lookup_commit(sha1);
@@ -397,20 +371,61 @@ static int is_a_merge(const unsigned char *sha1)
 
 static const char sign_off_header[] = "Signed-off-by: ";
 
+static void determine_author_info(void)
+{
+       char *name, *email, *date;
+
+       name = getenv("GIT_AUTHOR_NAME");
+       email = getenv("GIT_AUTHOR_EMAIL");
+       date = getenv("GIT_AUTHOR_DATE");
+
+       if (use_message) {
+               const char *a, *lb, *rb, *eol;
+
+               a = strstr(use_message_buffer, "\nauthor ");
+               if (!a)
+                       die("invalid commit: %s", use_message);
+
+               lb = strstr(a + 8, " <");
+               rb = strstr(a + 8, "> ");
+               eol = strchr(a + 8, '\n');
+               if (!lb || !rb || !eol)
+                       die("invalid commit: %s", use_message);
+
+               name = xstrndup(a + 8, lb - (a + 8));
+               email = xstrndup(lb + 2, rb - (lb + 2));
+               date = xstrndup(rb + 2, eol - (rb + 2));
+       }
+
+       if (force_author) {
+               const char *lb = strstr(force_author, " <");
+               const char *rb = strchr(force_author, '>');
+
+               if (!lb || !rb)
+                       die("malformed --author parameter");
+               name = xstrndup(force_author, lb - force_author);
+               email = xstrndup(lb + 2, rb - (lb + 2));
+       }
+
+       author_name = name;
+       author_email = email;
+       author_date = date;
+}
+
 static int prepare_to_commit(const char *index_file, const char *prefix)
 {
        struct stat statbuf;
        int commitable, saved_color_setting;
-       struct strbuf sb;
+       struct strbuf sb = STRBUF_INIT;
        char *buffer;
        FILE *fp;
        const char *hook_arg1 = NULL;
        const char *hook_arg2 = NULL;
+       int ident_shown = 0;
 
        if (!no_verify && run_hook(index_file, "pre-commit", NULL))
                return 0;
 
-       strbuf_init(&sb, 0);
        if (message.len) {
                strbuf_addbuf(&sb, &message);
                hook_arg1 = "message";
@@ -456,16 +471,16 @@ static int prepare_to_commit(const char *index_file, const char *prefix)
 
        fp = fopen(git_path(commit_editmsg), "w");
        if (fp == NULL)
-               die("could not open %s", git_path(commit_editmsg));
+               die("could not open %s: %s",
+                   git_path(commit_editmsg), strerror(errno));
 
        if (cleanup_mode != CLEANUP_NONE)
                stripspace(&sb, 0);
 
        if (signoff) {
-               struct strbuf sob;
+               struct strbuf sob = STRBUF_INIT;
                int i;
 
-               strbuf_init(&sob, 0);
                strbuf_addstr(&sob, sign_off_header);
                strbuf_addstr(&sob, fmt_name(getenv("GIT_COMMITTER_NAME"),
                                             getenv("GIT_COMMITTER_EMAIL")));
@@ -485,7 +500,14 @@ static int prepare_to_commit(const char *index_file, const char *prefix)
 
        strbuf_release(&sb);
 
+       determine_author_info();
+
+       /* This checks if committer ident is explicitly given */
+       git_committer_info(0);
        if (use_editor) {
+               char *author_ident;
+               const char *committer_ident;
+
                if (in_merge)
                        fprintf(fp,
                                "#\n"
@@ -498,22 +520,47 @@ static int prepare_to_commit(const char *index_file, const char *prefix)
 
                fprintf(fp,
                        "\n"
-                       "# Please enter the commit message for your changes.\n"
-                       "# (Comment lines starting with '#' will ");
+                       "# Please enter the commit message for your changes.");
                if (cleanup_mode == CLEANUP_ALL)
-                       fprintf(fp, "not be included)\n");
+                       fprintf(fp,
+                               " Lines starting\n"
+                               "# with '#' will be ignored, and an empty"
+                               " message aborts the commit.\n");
                else /* CLEANUP_SPACE, that is. */
-                       fprintf(fp, "be kept.\n"
-                               "# You can remove them yourself if you want to)\n");
+                       fprintf(fp,
+                               " Lines starting\n"
+                               "# with '#' will be kept; you may remove them"
+                               " yourself if you want to.\n"
+                               "# An empty message aborts the commit.\n");
                if (only_include_assumed)
                        fprintf(fp, "# %s\n", only_include_assumed);
 
+               author_ident = xstrdup(fmt_name(author_name, author_email));
+               committer_ident = fmt_name(getenv("GIT_COMMITTER_NAME"),
+                                          getenv("GIT_COMMITTER_EMAIL"));
+               if (strcmp(author_ident, committer_ident))
+                       fprintf(fp,
+                               "%s"
+                               "# Author:    %s\n",
+                               ident_shown++ ? "" : "#\n",
+                               author_ident);
+               free(author_ident);
+
+               if (!user_ident_explicitly_given)
+                       fprintf(fp,
+                               "%s"
+                               "# Committer: %s\n",
+                               ident_shown++ ? "" : "#\n",
+                               committer_ident);
+
+               if (ident_shown)
+                       fprintf(fp, "#\n");
+
                saved_color_setting = wt_status_use_color;
                wt_status_use_color = 0;
                commitable = run_status(fp, index_file, prefix, 1);
                wt_status_use_color = saved_color_setting;
        } else {
-               struct rev_info rev;
                unsigned char sha1[20];
                const char *parent = "HEAD";
 
@@ -525,16 +572,8 @@ static int prepare_to_commit(const char *index_file, const char *prefix)
 
                if (get_sha1(parent, sha1))
                        commitable = !!active_nr;
-               else {
-                       init_revisions(&rev, "");
-                       rev.abbrev = 0;
-                       setup_revisions(0, NULL, &rev, parent);
-                       DIFF_OPT_SET(&rev.diffopt, QUIET);
-                       DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
-                       run_diff_index(&rev, 1 /* cached */);
-
-                       commitable = !!DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES);
-               }
+               else
+                       commitable = index_differs_from(parent, 0);
        }
 
        fclose(fp);
@@ -542,7 +581,6 @@ static int prepare_to_commit(const char *index_file, const char *prefix)
        if (!commitable && !in_merge && !allow_empty &&
            !(amend && is_a_merge(head_sha1))) {
                run_status(stdout, index_file, prefix, 0);
-               unlink(commit_editmsg);
                return 0;
        }
 
@@ -569,7 +607,11 @@ static int prepare_to_commit(const char *index_file, const char *prefix)
                char index[PATH_MAX];
                const char *env[2] = { index, NULL };
                snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
-               launch_editor(git_path(commit_editmsg), NULL, env);
+               if (launch_editor(git_path(commit_editmsg), NULL, env)) {
+                       fprintf(stderr,
+                       "Please supply the message using either -m or -F option.\n");
+                       exit(1);
+               }
        }
 
        if (!no_verify &&
@@ -581,20 +623,19 @@ static int prepare_to_commit(const char *index_file, const char *prefix)
 }
 
 /*
- * Find out if the message starting at position 'start' in the strbuf
- * contains only whitespace and Signed-off-by lines.
+ * Find out if the message in the strbuf contains only whitespace and
+ * Signed-off-by lines.
  */
-static int message_is_empty(struct strbuf *sb, int start)
+static int message_is_empty(struct strbuf *sb)
 {
-       struct strbuf tmpl;
+       struct strbuf tmpl = STRBUF_INIT;
        const char *nl;
-       int eol, i;
+       int eol, i, start = 0;
 
        if (cleanup_mode == CLEANUP_NONE && sb->len)
                return 0;
 
        /* See if the template is just a prefix of the message. */
-       strbuf_init(&tmpl, 0);
        if (template_file && strbuf_read_file(&tmpl, template_file, 0) > 0) {
                stripspace(&tmpl, cleanup_mode == CLEANUP_ALL);
                if (start + tmpl.len <= sb->len &&
@@ -624,51 +665,43 @@ static int message_is_empty(struct strbuf *sb, int start)
        return 1;
 }
 
-static void determine_author_info(struct strbuf *sb)
+static const char *find_author_by_nickname(const char *name)
 {
-       char *name, *email, *date;
-
-       name = getenv("GIT_AUTHOR_NAME");
-       email = getenv("GIT_AUTHOR_EMAIL");
-       date = getenv("GIT_AUTHOR_DATE");
-
-       if (use_message) {
-               const char *a, *lb, *rb, *eol;
-
-               a = strstr(use_message_buffer, "\nauthor ");
-               if (!a)
-                       die("invalid commit: %s", use_message);
-
-               lb = strstr(a + 8, " <");
-               rb = strstr(a + 8, "> ");
-               eol = strchr(a + 8, '\n');
-               if (!lb || !rb || !eol)
-                       die("invalid commit: %s", use_message);
-
-               name = xstrndup(a + 8, lb - (a + 8));
-               email = xstrndup(lb + 2, rb - (lb + 2));
-               date = xstrndup(rb + 2, eol - (rb + 2));
-       }
-
-       if (force_author) {
-               const char *lb = strstr(force_author, " <");
-               const char *rb = strchr(force_author, '>');
-
-               if (!lb || !rb)
-                       die("malformed --author parameter");
-               name = xstrndup(force_author, lb - force_author);
-               email = xstrndup(lb + 2, rb - (lb + 2));
+       struct rev_info revs;
+       struct commit *commit;
+       struct strbuf buf = STRBUF_INIT;
+       const char *av[20];
+       int ac = 0;
+
+       init_revisions(&revs, NULL);
+       strbuf_addf(&buf, "--author=%s", name);
+       av[++ac] = "--all";
+       av[++ac] = "-i";
+       av[++ac] = buf.buf;
+       av[++ac] = NULL;
+       setup_revisions(ac, av, &revs, NULL);
+       prepare_revision_walk(&revs);
+       commit = get_revision(&revs);
+       if (commit) {
+               strbuf_release(&buf);
+               format_commit_message(commit, "%an <%ae>", &buf, DATE_NORMAL);
+               return strbuf_detach(&buf, NULL);
        }
-
-       strbuf_addf(sb, "author %s\n", fmt_ident(name, email, date, IDENT_ERROR_ON_NO_NAME));
+       die("No existing author found with '%s'", name);
 }
 
 static int parse_and_validate_options(int argc, const char *argv[],
-                                     const char * const usage[])
+                                     const char * const usage[],
+                                     const char *prefix)
 {
        int f = 0;
 
        argc = parse_options(argc, argv, builtin_commit_options, usage, 0);
+       logfile = parse_options_fix_filename(prefix, logfile);
+       template_file = parse_options_fix_filename(prefix, template_file);
+
+       if (force_author && !strchr(force_author, '>'))
+               force_author = find_author_by_nickname(force_author);
 
        if (logfile || message.len || use_message)
                use_editor = 0;
@@ -747,10 +780,8 @@ static int parse_and_validate_options(int argc, const char *argv[],
                die("No paths with --include/--only does not make sense.");
        if (argc == 0 && only && amend)
                only_include_assumed = "Clever... amending the last one with dirty index.";
-       if (argc > 0 && !also && !only) {
+       if (argc > 0 && !also && !only)
                only_include_assumed = "Explicit paths specified without -i nor -o; assuming --only paths...";
-               also = 0;
-       }
        if (!cleanup_arg || !strcmp(cleanup_arg, "default"))
                cleanup_mode = use_editor ? CLEANUP_ALL : CLEANUP_SPACE;
        else if (!strcmp(cleanup_arg, "verbatim"))
@@ -762,6 +793,17 @@ static int parse_and_validate_options(int argc, const char *argv[],
        else
                die("Invalid cleanup mode %s", cleanup_arg);
 
+       if (!untracked_files_arg)
+               ; /* default already initialized */
+       else if (!strcmp(untracked_files_arg, "no"))
+               show_untracked_files = SHOW_NO_UNTRACKED_FILES;
+       else if (!strcmp(untracked_files_arg, "normal"))
+               show_untracked_files = SHOW_NORMAL_UNTRACKED_FILES;
+       else if (!strcmp(untracked_files_arg, "all"))
+               show_untracked_files = SHOW_ALL_UNTRACKED_FILES;
+       else
+               die("Invalid untracked files mode '%s'", untracked_files_arg);
+
        if (all && argc > 0)
                die("Paths with -a does not make sense.");
        else if (interactive && argc > 0)
@@ -775,12 +817,15 @@ int cmd_status(int argc, const char **argv, const char *prefix)
        const char *index_file;
        int commitable;
 
-       git_config(git_status_config);
+       git_config(git_status_config, NULL);
 
        if (wt_status_use_color == -1)
                wt_status_use_color = git_use_color_default;
 
-       argc = parse_and_validate_options(argc, argv, builtin_status_usage);
+       if (diff_use_color_default == -1)
+               diff_use_color_default = git_use_color_default;
+
+       argc = parse_and_validate_options(argc, argv, builtin_status_usage, prefix);
 
        index_file = prepare_index(argc, argv, prefix);
 
@@ -795,6 +840,9 @@ static void print_summary(const char *prefix, const unsigned char *sha1)
 {
        struct rev_info rev;
        struct commit *commit;
+       static const char *format = "format:%h] %s";
+       unsigned char junk_sha1[20];
+       const char *head = resolve_ref("HEAD", junk_sha1, 0, NULL);
 
        commit = lookup_commit(sha1);
        if (!commit)
@@ -812,63 +860,54 @@ static void print_summary(const char *prefix, const unsigned char *sha1)
 
        rev.verbose_header = 1;
        rev.show_root_diff = 1;
-       rev.commit_format = get_commit_format("format:%h: %s");
+       get_commit_format(format, &rev);
        rev.always_show_header = 0;
        rev.diffopt.detect_rename = 1;
        rev.diffopt.rename_limit = 100;
        rev.diffopt.break_opt = 0;
        diff_setup_done(&rev.diffopt);
 
-       printf("Created %scommit ", initial_commit ? "initial " : "");
+       printf("[%s%s ",
+               !prefixcmp(head, "refs/heads/") ?
+                       head + 11 :
+                       !strcmp(head, "HEAD") ?
+                               "detached HEAD" :
+                               head,
+               initial_commit ? " (root-commit)" : "");
 
        if (!log_tree_commit(&rev, commit)) {
                struct strbuf buf = STRBUF_INIT;
-               format_commit_message(commit, "%h: %s", &buf);
+               format_commit_message(commit, format + 7, &buf, DATE_NORMAL);
                printf("%s\n", buf.buf);
                strbuf_release(&buf);
        }
 }
 
-int git_commit_config(const char *k, const char *v)
+static int git_commit_config(const char *k, const char *v, void *cb)
 {
-       if (!strcmp(k, "commit.template")) {
-               if (!v)
-                       return config_error_nonbool(v);
-               template_file = xstrdup(v);
-               return 0;
-       }
+       if (!strcmp(k, "commit.template"))
+               return git_config_string(&template_file, k, v);
 
-       return git_status_config(k, v);
-}
-
-static const char commit_utf8_warn[] =
-"Warning: commit message does not conform to UTF-8.\n"
-"You may want to amend it after fixing the message, or set the config\n"
-"variable i18n.commitencoding to the encoding your project uses.\n";
-
-static void add_parent(struct strbuf *sb, const unsigned char *sha1)
-{
-       struct object *obj = parse_object(sha1);
-       const char *parent = sha1_to_hex(sha1);
-       if (!obj)
-               die("Unable to find commit parent %s", parent);
-       if (obj->type != OBJ_COMMIT)
-               die("Parent %s isn't a proper commit", parent);
-       strbuf_addf(sb, "parent %s\n", parent);
+       return git_status_config(k, v, cb);
 }
 
 int cmd_commit(int argc, const char **argv, const char *prefix)
 {
-       int header_len;
-       struct strbuf sb;
+       struct strbuf sb = STRBUF_INIT;
        const char *index_file, *reflog_msg;
        char *nl, *p;
        unsigned char commit_sha1[20];
        struct ref_lock *ref_lock;
+       struct commit_list *parents = NULL, **pptr = &parents;
+       struct stat statbuf;
+       int allow_fast_forward = 1;
+
+       git_config(git_commit_config, NULL);
 
-       git_config(git_commit_config);
+       if (wt_status_use_color == -1)
+               wt_status_use_color = git_use_color_default;
 
-       argc = parse_and_validate_options(argc, argv, builtin_commit_usage);
+       argc = parse_and_validate_options(argc, argv, builtin_commit_usage, prefix);
 
        index_file = prepare_index(argc, argv, prefix);
 
@@ -879,13 +918,6 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
                return 1;
        }
 
-       /*
-        * The commit object
-        */
-       strbuf_init(&sb, 0);
-       strbuf_addf(&sb, "tree %s\n",
-                   sha1_to_hex(active_cache_tree->sha1));
-
        /* Determine parents */
        if (initial_commit) {
                reflog_msg = "commit (initial)";
@@ -899,14 +931,13 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
                        die("could not parse HEAD commit");
 
                for (c = commit->parents; c; c = c->next)
-                       add_parent(&sb, c->item->object.sha1);
+                       pptr = &commit_list_insert(c->item, pptr)->next;
        } else if (in_merge) {
-               struct strbuf m;
+               struct strbuf m = STRBUF_INIT;
                FILE *fp;
 
                reflog_msg = "commit (merge)";
-               add_parent(&sb, head_sha1);
-               strbuf_init(&m, 0);
+               pptr = &commit_list_insert(lookup_commit(head_sha1), pptr)->next;
                fp = fopen(git_path("MERGE_HEAD"), "r");
                if (fp == NULL)
                        die("could not open %s for reading: %s",
@@ -915,44 +946,49 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
                        unsigned char sha1[20];
                        if (get_sha1_hex(m.buf, sha1) < 0)
                                die("Corrupt MERGE_HEAD file (%s)", m.buf);
-                       add_parent(&sb, sha1);
+                       pptr = &commit_list_insert(lookup_commit(sha1), pptr)->next;
                }
                fclose(fp);
                strbuf_release(&m);
+               if (!stat(git_path("MERGE_MODE"), &statbuf)) {
+                       if (strbuf_read_file(&sb, git_path("MERGE_MODE"), 0) < 0)
+                               die("could not read MERGE_MODE: %s",
+                                               strerror(errno));
+                       if (!strcmp(sb.buf, "no-ff"))
+                               allow_fast_forward = 0;
+               }
+               if (allow_fast_forward)
+                       parents = reduce_heads(parents);
        } else {
                reflog_msg = "commit";
-               strbuf_addf(&sb, "parent %s\n", sha1_to_hex(head_sha1));
+               pptr = &commit_list_insert(lookup_commit(head_sha1), pptr)->next;
        }
 
-       determine_author_info(&sb);
-       strbuf_addf(&sb, "committer %s\n", git_committer_info(IDENT_ERROR_ON_NO_NAME));
-       if (!is_encoding_utf8(git_commit_encoding))
-               strbuf_addf(&sb, "encoding %s\n", git_commit_encoding);
-       strbuf_addch(&sb, '\n');
-
        /* Finally, get the commit message */
-       header_len = sb.len;
+       strbuf_reset(&sb);
        if (strbuf_read_file(&sb, git_path(commit_editmsg), 0) < 0) {
                rollback_index_files();
                die("could not read commit message");
        }
 
        /* Truncate the message just before the diff, if any. */
-       p = strstr(sb.buf, "\ndiff --git a/");
-       if (p != NULL)
-               strbuf_setlen(&sb, p - sb.buf + 1);
+       if (verbose) {
+               p = strstr(sb.buf, "\ndiff --git ");
+               if (p != NULL)
+                       strbuf_setlen(&sb, p - sb.buf + 1);
+       }
 
        if (cleanup_mode != CLEANUP_NONE)
                stripspace(&sb, cleanup_mode == CLEANUP_ALL);
-       if (sb.len < header_len || message_is_empty(&sb, header_len)) {
+       if (message_is_empty(&sb)) {
                rollback_index_files();
-               die("no commit message?  aborting commit.");
+               fprintf(stderr, "Aborting commit due to empty commit message.\n");
+               exit(1);
        }
-       strbuf_addch(&sb, '\0');
-       if (is_encoding_utf8(git_commit_encoding) && !is_utf8(sb.buf))
-               fprintf(stderr, commit_utf8_warn);
 
-       if (write_sha1_file(sb.buf, sb.len - 1, commit_type, commit_sha1)) {
+       if (commit_tree(sb.buf, active_cache_tree->sha1, parents, commit_sha1,
+                       fmt_ident(author_name, author_email, author_date,
+                               IDENT_ERROR_ON_NO_NAME))) {
                rollback_index_files();
                die("failed to write commit object");
        }
@@ -961,12 +997,11 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
                                           initial_commit ? NULL : head_sha1,
                                           0);
 
-       nl = strchr(sb.buf + header_len, '\n');
+       nl = strchr(sb.buf, '\n');
        if (nl)
                strbuf_setlen(&sb, nl + 1 - sb.buf);
        else
                strbuf_addch(&sb, '\n');
-       strbuf_remove(&sb, 0, header_len);
        strbuf_insert(&sb, 0, reflog_msg, strlen(reflog_msg));
        strbuf_insert(&sb, strlen(reflog_msg), ": ", 2);
 
@@ -981,6 +1016,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 
        unlink(git_path("MERGE_HEAD"));
        unlink(git_path("MERGE_MSG"));
+       unlink(git_path("MERGE_MODE"));
        unlink(git_path("SQUASH_MSG"));
 
        if (commit_index_files())