merge-recursive: don't segfault while handling rename clashes
[gitweb.git] / revision.c
index ffbed3fbf22c22b8862c49bdddd10cab201f86a2..34ee490ea0181091c375765141bd83e71ab2defe 100644 (file)
@@ -6,9 +6,12 @@
 #include "diff.h"
 #include "refs.h"
 #include "revision.h"
+#include "graph.h"
 #include "grep.h"
 #include "reflog-walk.h"
 #include "patch-ids.h"
+#include "decorate.h"
+#include "log-tree.h"
 
 volatile show_early_output_fn_t show_early_output;
 
@@ -180,8 +183,11 @@ static struct commit *handle_commit(struct rev_info *revs, struct object *object
                if (!tag->tagged)
                        die("bad tag");
                object = parse_object(tag->tagged->sha1);
-               if (!object)
+               if (!object) {
+                       if (flags & UNINTERESTING)
+                               return NULL;
                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
+               }
        }
 
        /*
@@ -197,6 +203,8 @@ static struct commit *handle_commit(struct rev_info *revs, struct object *object
                        mark_parents_uninteresting(commit);
                        revs->limited = 1;
                }
+               if (revs->show_source && !commit->util)
+                       commit->util = (void *) name;
                return commit;
        }
 
@@ -258,7 +266,7 @@ static int tree_difference = REV_TREE_SAME;
 static void file_add_remove(struct diff_options *options,
                    int addremove, unsigned mode,
                    const unsigned char *sha1,
-                   const char *base, const char *path)
+                   const char *fullpath)
 {
        int diff = REV_TREE_DIFFERENT;
 
@@ -284,16 +292,37 @@ static void file_change(struct diff_options *options,
                 unsigned old_mode, unsigned new_mode,
                 const unsigned char *old_sha1,
                 const unsigned char *new_sha1,
-                const char *base, const char *path)
+                const char *fullpath)
 {
        tree_difference = REV_TREE_DIFFERENT;
        DIFF_OPT_SET(options, HAS_CHANGES);
 }
 
-static int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
+static int rev_compare_tree(struct rev_info *revs, struct commit *parent, struct commit *commit)
 {
+       struct tree *t1 = parent->tree;
+       struct tree *t2 = commit->tree;
+
        if (!t1)
                return REV_TREE_NEW;
+
+       if (revs->simplify_by_decoration) {
+               /*
+                * If we are simplifying by decoration, then the commit
+                * is worth showing if it has a tag pointing at it.
+                */
+               if (lookup_decoration(&name_decoration, &commit->object))
+                       return REV_TREE_DIFFERENT;
+               /*
+                * A commit that is not pointed by a tag is uninteresting
+                * if we are not limited by path.  This means that you will
+                * see the usual "commits that touch the paths" plus any
+                * tagged commit by specifying both --simplify-by-decoration
+                * and pathspec.
+                */
+               if (!revs->prune_data)
+                       return REV_TREE_SAME;
+       }
        if (!t2)
                return REV_TREE_DIFFERENT;
        tree_difference = REV_TREE_SAME;
@@ -304,12 +333,13 @@ static int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree
        return tree_difference;
 }
 
-static int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
+static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
 {
        int retval;
        void *tree;
        unsigned long size;
        struct tree_desc empty, real;
+       struct tree *t1 = commit->tree;
 
        if (!t1)
                return 0;
@@ -343,7 +373,7 @@ static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
                return;
 
        if (!commit->parents) {
-               if (rev_same_tree_as_empty(revs, commit->tree))
+               if (rev_same_tree_as_empty(revs, commit))
                        commit->object.flags |= TREESAME;
                return;
        }
@@ -363,7 +393,7 @@ static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
                        die("cannot simplify commit %s (because of %s)",
                            sha1_to_hex(commit->object.sha1),
                            sha1_to_hex(p->object.sha1));
-               switch (rev_compare_tree(revs, p->tree, commit->tree)) {
+               switch (rev_compare_tree(revs, p, commit)) {
                case REV_TREE_SAME:
                        tree_same = 1;
                        if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
@@ -383,7 +413,7 @@ static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 
                case REV_TREE_NEW:
                        if (revs->remove_empty_trees &&
-                           rev_same_tree_as_empty(revs, p->tree)) {
+                           rev_same_tree_as_empty(revs, p)) {
                                /* We are adding all the specified
                                 * paths from this parent, so the
                                 * history beyond this parent is not
@@ -411,11 +441,26 @@ static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
        commit->object.flags |= TREESAME;
 }
 
-static int add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
+static void insert_by_date_cached(struct commit *p, struct commit_list **head,
+                   struct commit_list *cached_base, struct commit_list **cache)
+{
+       struct commit_list *new_entry;
+
+       if (cached_base && p->date < cached_base->item->date)
+               new_entry = insert_by_date(p, &cached_base->next);
+       else
+               new_entry = insert_by_date(p, head);
+
+       if (cache && (!*cache || p->date < (*cache)->item->date))
+               *cache = new_entry;
+}
+
+static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
+                   struct commit_list **list, struct commit_list **cache_ptr)
 {
        struct commit_list *parent = commit->parents;
        unsigned left_flag;
-       int add, rest;
+       struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;
 
        if (commit->object.flags & ADDED)
                return 0;
@@ -437,15 +482,16 @@ static int add_parents_to_list(struct rev_info *revs, struct commit *commit, str
                while (parent) {
                        struct commit *p = parent->item;
                        parent = parent->next;
+                       if (p)
+                               p->object.flags |= UNINTERESTING;
                        if (parse_commit(p) < 0)
-                               return -1;
-                       p->object.flags |= UNINTERESTING;
+                               continue;
                        if (p->parents)
                                mark_parents_uninteresting(p);
                        if (p->object.flags & SEEN)
                                continue;
                        p->object.flags |= SEEN;
-                       insert_by_date(p, list);
+                       insert_by_date_cached(p, list, cached_base, cache_ptr);
                }
                return 0;
        }
@@ -462,19 +508,20 @@ static int add_parents_to_list(struct rev_info *revs, struct commit *commit, str
 
        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 
-       rest = !revs->first_parent_only;
-       for (parent = commit->parents, add = 1; parent; add = rest) {
+       for (parent = commit->parents; parent; parent = parent->next) {
                struct commit *p = parent->item;
 
-               parent = parent->next;
                if (parse_commit(p) < 0)
                        return -1;
+               if (revs->show_source && !p->util)
+                       p->util = commit->util;
                p->object.flags |= left_flag;
-               if (p->object.flags & SEEN)
-                       continue;
-               p->object.flags |= SEEN;
-               if (add)
-                       insert_by_date(p, list);
+               if (!(p->object.flags & SEEN)) {
+                       p->object.flags |= SEEN;
+                       insert_by_date_cached(p, list, cached_base, cache_ptr);
+               }
+               if (revs->first_parent_only)
+                       break;
        }
        return 0;
 }
@@ -612,7 +659,7 @@ static int limit_list(struct rev_info *revs)
 
                if (revs->max_age != -1 && (commit->date < revs->max_age))
                        obj->flags |= UNINTERESTING;
-               if (add_parents_to_list(revs, commit, &list) < 0)
+               if (add_parents_to_list(revs, commit, &list, NULL) < 0)
                        return -1;
                if (obj->flags & UNINTERESTING) {
                        mark_parents_uninteresting(commit);
@@ -766,6 +813,10 @@ void init_revisions(struct rev_info *revs, const char *prefix)
 
        revs->commit_format = CMIT_FMT_DEFAULT;
 
+       revs->grep_filter.status_only = 1;
+       revs->grep_filter.pattern_tail = &(revs->grep_filter.pattern_list);
+       revs->grep_filter.regflags = REG_NEWLINE;
+
        diff_setup(&revs->diffopt);
        if (prefix && !revs->diffopt.prefix) {
                revs->diffopt.prefix = prefix;
@@ -911,35 +962,31 @@ int handle_revision_arg(const char *arg, struct rev_info *revs,
        return 0;
 }
 
+void read_revisions_from_stdin(struct rev_info *revs)
+{
+       char line[1000];
+
+       while (fgets(line, sizeof(line), stdin) != NULL) {
+               int len = strlen(line);
+               if (len && line[len - 1] == '\n')
+                       line[--len] = '\0';
+               if (!len)
+                       break;
+               if (line[0] == '-')
+                       die("options not supported in --stdin mode");
+               if (handle_revision_arg(line, revs, 0, 1))
+                       die("bad revision '%s'", line);
+       }
+}
+
 static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
 {
-       if (!revs->grep_filter) {
-               struct grep_opt *opt = xcalloc(1, sizeof(*opt));
-               opt->status_only = 1;
-               opt->pattern_tail = &(opt->pattern_list);
-               opt->regflags = REG_NEWLINE;
-               revs->grep_filter = opt;
-       }
-       append_grep_pattern(revs->grep_filter, ptn,
-                           "command line", 0, what);
+       append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
 }
 
-static void add_header_grep(struct rev_info *revs, const char *field, const char *pattern)
+static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
 {
-       char *pat;
-       const char *prefix;
-       int patlen, fldlen;
-
-       fldlen = strlen(field);
-       patlen = strlen(pattern);
-       pat = xmalloc(patlen + fldlen + 10);
-       prefix = ".*";
-       if (*pattern == '^') {
-               prefix = "";
-               pattern++;
-       }
-       sprintf(pat, "^%s %s%s", field, prefix, pattern);
-       add_grep(revs, pat, GREP_PATTERN_HEAD);
+       append_header_grep_pattern(&revs->grep_filter, field, pattern);
 }
 
 static void add_message_grep(struct rev_info *revs, const char *pattern)
@@ -947,14 +994,229 @@ static void add_message_grep(struct rev_info *revs, const char *pattern)
        add_grep(revs, pattern, GREP_PATTERN_BODY);
 }
 
-static void add_ignore_packed(struct rev_info *revs, const char *name)
+static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
+                              int *unkc, const char **unkv)
 {
-       int num = ++revs->num_ignore_packed;
+       const char *arg = argv[0];
+
+       /* pseudo revision arguments */
+       if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
+           !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
+           !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
+           !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk"))
+       {
+               unkv[(*unkc)++] = arg;
+               return 1;
+       }
 
-       revs->ignore_packed = xrealloc(revs->ignore_packed,
-                                      sizeof(const char **) * (num + 1));
-       revs->ignore_packed[num-1] = name;
-       revs->ignore_packed[num] = NULL;
+       if (!prefixcmp(arg, "--max-count=")) {
+               revs->max_count = atoi(arg + 12);
+       } else if (!prefixcmp(arg, "--skip=")) {
+               revs->skip_count = atoi(arg + 7);
+       } else if ((*arg == '-') && isdigit(arg[1])) {
+       /* accept -<digit>, like traditional "head" */
+               revs->max_count = atoi(arg + 1);
+       } else if (!strcmp(arg, "-n")) {
+               if (argc <= 1)
+                       return error("-n requires an argument");
+               revs->max_count = atoi(argv[1]);
+               return 2;
+       } else if (!prefixcmp(arg, "-n")) {
+               revs->max_count = atoi(arg + 2);
+       } else if (!prefixcmp(arg, "--max-age=")) {
+               revs->max_age = atoi(arg + 10);
+       } else if (!prefixcmp(arg, "--since=")) {
+               revs->max_age = approxidate(arg + 8);
+       } else if (!prefixcmp(arg, "--after=")) {
+               revs->max_age = approxidate(arg + 8);
+       } else if (!prefixcmp(arg, "--min-age=")) {
+               revs->min_age = atoi(arg + 10);
+       } else if (!prefixcmp(arg, "--before=")) {
+               revs->min_age = approxidate(arg + 9);
+       } else if (!prefixcmp(arg, "--until=")) {
+               revs->min_age = approxidate(arg + 8);
+       } else if (!strcmp(arg, "--first-parent")) {
+               revs->first_parent_only = 1;
+       } else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
+               init_reflog_walk(&revs->reflog_info);
+       } else if (!strcmp(arg, "--default")) {
+               if (argc <= 1)
+                       return error("bad --default argument");
+               revs->def = argv[1];
+               return 2;
+       } else if (!strcmp(arg, "--merge")) {
+               revs->show_merge = 1;
+       } else if (!strcmp(arg, "--topo-order")) {
+               revs->lifo = 1;
+               revs->topo_order = 1;
+       } else if (!strcmp(arg, "--simplify-merges")) {
+               revs->simplify_merges = 1;
+               revs->rewrite_parents = 1;
+               revs->simplify_history = 0;
+               revs->limited = 1;
+       } else if (!strcmp(arg, "--simplify-by-decoration")) {
+               revs->simplify_merges = 1;
+               revs->rewrite_parents = 1;
+               revs->simplify_history = 0;
+               revs->simplify_by_decoration = 1;
+               revs->limited = 1;
+               revs->prune = 1;
+               load_ref_decorations();
+       } else if (!strcmp(arg, "--date-order")) {
+               revs->lifo = 0;
+               revs->topo_order = 1;
+       } else if (!prefixcmp(arg, "--early-output")) {
+               int count = 100;
+               switch (arg[14]) {
+               case '=':
+                       count = atoi(arg+15);
+                       /* Fallthrough */
+               case 0:
+                       revs->topo_order = 1;
+                      revs->early_output = count;
+               }
+       } else if (!strcmp(arg, "--parents")) {
+               revs->rewrite_parents = 1;
+               revs->print_parents = 1;
+       } else if (!strcmp(arg, "--dense")) {
+               revs->dense = 1;
+       } else if (!strcmp(arg, "--sparse")) {
+               revs->dense = 0;
+       } else if (!strcmp(arg, "--show-all")) {
+               revs->show_all = 1;
+       } else if (!strcmp(arg, "--remove-empty")) {
+               revs->remove_empty_trees = 1;
+       } else if (!strcmp(arg, "--no-merges")) {
+               revs->no_merges = 1;
+       } else if (!strcmp(arg, "--boundary")) {
+               revs->boundary = 1;
+       } else if (!strcmp(arg, "--left-right")) {
+               revs->left_right = 1;
+       } else if (!strcmp(arg, "--cherry-pick")) {
+               revs->cherry_pick = 1;
+               revs->limited = 1;
+       } else if (!strcmp(arg, "--objects")) {
+               revs->tag_objects = 1;
+               revs->tree_objects = 1;
+               revs->blob_objects = 1;
+       } else if (!strcmp(arg, "--objects-edge")) {
+               revs->tag_objects = 1;
+               revs->tree_objects = 1;
+               revs->blob_objects = 1;
+               revs->edge_hint = 1;
+       } else if (!strcmp(arg, "--unpacked")) {
+               revs->unpacked = 1;
+       } else if (!prefixcmp(arg, "--unpacked=")) {
+               die("--unpacked=<packfile> no longer supported.");
+       } else if (!strcmp(arg, "-r")) {
+               revs->diff = 1;
+               DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
+       } else if (!strcmp(arg, "-t")) {
+               revs->diff = 1;
+               DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
+               DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
+       } else if (!strcmp(arg, "-m")) {
+               revs->ignore_merges = 0;
+       } else if (!strcmp(arg, "-c")) {
+               revs->diff = 1;
+               revs->dense_combined_merges = 0;
+               revs->combine_merges = 1;
+       } else if (!strcmp(arg, "--cc")) {
+               revs->diff = 1;
+               revs->dense_combined_merges = 1;
+               revs->combine_merges = 1;
+       } else if (!strcmp(arg, "-v")) {
+               revs->verbose_header = 1;
+       } else if (!strcmp(arg, "--pretty")) {
+               revs->verbose_header = 1;
+               get_commit_format(arg+8, revs);
+       } else if (!prefixcmp(arg, "--pretty=")) {
+               revs->verbose_header = 1;
+               get_commit_format(arg+9, revs);
+       } else if (!strcmp(arg, "--graph")) {
+               revs->topo_order = 1;
+               revs->rewrite_parents = 1;
+               revs->graph = graph_init(revs);
+       } else if (!strcmp(arg, "--root")) {
+               revs->show_root_diff = 1;
+       } else if (!strcmp(arg, "--no-commit-id")) {
+               revs->no_commit_id = 1;
+       } else if (!strcmp(arg, "--always")) {
+               revs->always_show_header = 1;
+       } else if (!strcmp(arg, "--no-abbrev")) {
+               revs->abbrev = 0;
+       } else if (!strcmp(arg, "--abbrev")) {
+               revs->abbrev = DEFAULT_ABBREV;
+       } else if (!prefixcmp(arg, "--abbrev=")) {
+               revs->abbrev = strtoul(arg + 9, NULL, 10);
+               if (revs->abbrev < MINIMUM_ABBREV)
+                       revs->abbrev = MINIMUM_ABBREV;
+               else if (revs->abbrev > 40)
+                       revs->abbrev = 40;
+       } else if (!strcmp(arg, "--abbrev-commit")) {
+               revs->abbrev_commit = 1;
+       } else if (!strcmp(arg, "--full-diff")) {
+               revs->diff = 1;
+               revs->full_diff = 1;
+       } else if (!strcmp(arg, "--full-history")) {
+               revs->simplify_history = 0;
+       } else if (!strcmp(arg, "--relative-date")) {
+               revs->date_mode = DATE_RELATIVE;
+       } else if (!strncmp(arg, "--date=", 7)) {
+               revs->date_mode = parse_date_format(arg + 7);
+       } else if (!strcmp(arg, "--log-size")) {
+               revs->show_log_size = 1;
+       }
+       /*
+        * Grepping the commit log
+        */
+       else if (!prefixcmp(arg, "--author=")) {
+               add_header_grep(revs, GREP_HEADER_AUTHOR, arg+9);
+       } else if (!prefixcmp(arg, "--committer=")) {
+               add_header_grep(revs, GREP_HEADER_COMMITTER, arg+12);
+       } else if (!prefixcmp(arg, "--grep=")) {
+               add_message_grep(revs, arg+7);
+       } else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
+               revs->grep_filter.regflags |= REG_EXTENDED;
+       } else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
+               revs->grep_filter.regflags |= REG_ICASE;
+       } else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
+               revs->grep_filter.fixed = 1;
+       } else if (!strcmp(arg, "--all-match")) {
+               revs->grep_filter.all_match = 1;
+       } else if (!prefixcmp(arg, "--encoding=")) {
+               arg += 11;
+               if (strcmp(arg, "none"))
+                       git_log_output_encoding = xstrdup(arg);
+               else
+                       git_log_output_encoding = "";
+       } else if (!strcmp(arg, "--reverse")) {
+               revs->reverse ^= 1;
+       } else if (!strcmp(arg, "--children")) {
+               revs->children.name = "children";
+               revs->limited = 1;
+       } else {
+               int opts = diff_opt_parse(&revs->diffopt, argv, argc);
+               if (!opts)
+                       unkv[(*unkc)++] = arg;
+               return opts;
+       }
+
+       return 1;
+}
+
+void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
+                       const struct option *options,
+                       const char * const usagestr[])
+{
+       int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
+                                   &ctx->cpidx, ctx->out);
+       if (n <= 0) {
+               error("unknown option `%s'", ctx->argv[0]);
+               usage_with_options(usagestr, options);
+       }
+       ctx->argv += n;
+       ctx->argc -= n;
 }
 
 /*
@@ -966,12 +1228,7 @@ static void add_ignore_packed(struct rev_info *revs, const char *name)
  */
 int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
 {
-       int i, flags, seen_dashdash, show_merge;
-       const char **unrecognized = argv + 1;
-       int left = 1;
-       int all_match = 0;
-       int regflags = 0;
-       int fixed = 0;
+       int i, flags, left, seen_dashdash;
 
        /* First, search for "--" */
        seen_dashdash = 0;
@@ -987,60 +1244,16 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
                break;
        }
 
-       flags = show_merge = 0;
-       for (i = 1; i < argc; i++) {
+       /* Second, deal with arguments and options */
+       flags = 0;
+       for (left = i = 1; i < argc; i++) {
                const char *arg = argv[i];
                if (*arg == '-') {
                        int opts;
-                       if (!prefixcmp(arg, "--max-count=")) {
-                               revs->max_count = atoi(arg + 12);
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--skip=")) {
-                               revs->skip_count = atoi(arg + 7);
-                               continue;
-                       }
-                       /* accept -<digit>, like traditional "head" */
-                       if ((*arg == '-') && isdigit(arg[1])) {
-                               revs->max_count = atoi(arg + 1);
-                               continue;
-                       }
-                       if (!strcmp(arg, "-n")) {
-                               if (argc <= i + 1)
-                                       die("-n requires an argument");
-                               revs->max_count = atoi(argv[++i]);
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "-n")) {
-                               revs->max_count = atoi(arg + 2);
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--max-age=")) {
-                               revs->max_age = atoi(arg + 10);
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--since=")) {
-                               revs->max_age = approxidate(arg + 8);
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--after=")) {
-                               revs->max_age = approxidate(arg + 8);
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--min-age=")) {
-                               revs->min_age = atoi(arg + 10);
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--before=")) {
-                               revs->min_age = approxidate(arg + 9);
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--until=")) {
-                               revs->min_age = approxidate(arg + 8);
-                               continue;
-                       }
+
                        if (!strcmp(arg, "--all")) {
                                handle_refs(revs, flags, for_each_ref);
+                               handle_refs(revs, flags, head_ref);
                                continue;
                        }
                        if (!strcmp(arg, "--branches")) {
@@ -1055,253 +1268,14 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
                                handle_refs(revs, flags, for_each_remote_ref);
                                continue;
                        }
-                       if (!strcmp(arg, "--first-parent")) {
-                               revs->first_parent_only = 1;
-                               continue;
-                       }
                        if (!strcmp(arg, "--reflog")) {
                                handle_reflog(revs, flags);
                                continue;
                        }
-                       if (!strcmp(arg, "-g") ||
-                                       !strcmp(arg, "--walk-reflogs")) {
-                               init_reflog_walk(&revs->reflog_info);
-                               continue;
-                       }
                        if (!strcmp(arg, "--not")) {
                                flags ^= UNINTERESTING;
                                continue;
                        }
-                       if (!strcmp(arg, "--default")) {
-                               if (++i >= argc)
-                                       die("bad --default argument");
-                               def = argv[i];
-                               continue;
-                       }
-                       if (!strcmp(arg, "--merge")) {
-                               show_merge = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--topo-order")) {
-                               revs->lifo = 1;
-                               revs->topo_order = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--date-order")) {
-                               revs->lifo = 0;
-                               revs->topo_order = 1;
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--early-output")) {
-                               int count = 100;
-                               switch (arg[14]) {
-                               case '=':
-                                       count = atoi(arg+15);
-                                       /* Fallthrough */
-                               case 0:
-                                       revs->topo_order = 1;
-                                       revs->early_output = count;
-                                       continue;
-                               }
-                       }
-                       if (!strcmp(arg, "--parents")) {
-                               revs->parents = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--dense")) {
-                               revs->dense = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--sparse")) {
-                               revs->dense = 0;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--show-all")) {
-                               revs->show_all = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--remove-empty")) {
-                               revs->remove_empty_trees = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--no-merges")) {
-                               revs->no_merges = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--boundary")) {
-                               revs->boundary = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--left-right")) {
-                               revs->left_right = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--cherry-pick")) {
-                               revs->cherry_pick = 1;
-                               revs->limited = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--objects")) {
-                               revs->tag_objects = 1;
-                               revs->tree_objects = 1;
-                               revs->blob_objects = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--objects-edge")) {
-                               revs->tag_objects = 1;
-                               revs->tree_objects = 1;
-                               revs->blob_objects = 1;
-                               revs->edge_hint = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--unpacked")) {
-                               revs->unpacked = 1;
-                               free(revs->ignore_packed);
-                               revs->ignore_packed = NULL;
-                               revs->num_ignore_packed = 0;
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--unpacked=")) {
-                               revs->unpacked = 1;
-                               add_ignore_packed(revs, arg+11);
-                               continue;
-                       }
-                       if (!strcmp(arg, "-r")) {
-                               revs->diff = 1;
-                               DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
-                               continue;
-                       }
-                       if (!strcmp(arg, "-t")) {
-                               revs->diff = 1;
-                               DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
-                               DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
-                               continue;
-                       }
-                       if (!strcmp(arg, "-m")) {
-                               revs->ignore_merges = 0;
-                               continue;
-                       }
-                       if (!strcmp(arg, "-c")) {
-                               revs->diff = 1;
-                               revs->dense_combined_merges = 0;
-                               revs->combine_merges = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--cc")) {
-                               revs->diff = 1;
-                               revs->dense_combined_merges = 1;
-                               revs->combine_merges = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "-v")) {
-                               revs->verbose_header = 1;
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--pretty")) {
-                               revs->verbose_header = 1;
-                               revs->commit_format = get_commit_format(arg+8);
-                               continue;
-                       }
-                       if (!strcmp(arg, "--root")) {
-                               revs->show_root_diff = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--no-commit-id")) {
-                               revs->no_commit_id = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--always")) {
-                               revs->always_show_header = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--no-abbrev")) {
-                               revs->abbrev = 0;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--abbrev")) {
-                               revs->abbrev = DEFAULT_ABBREV;
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--abbrev=")) {
-                               revs->abbrev = strtoul(arg + 9, NULL, 10);
-                               if (revs->abbrev < MINIMUM_ABBREV)
-                                       revs->abbrev = MINIMUM_ABBREV;
-                               else if (revs->abbrev > 40)
-                                       revs->abbrev = 40;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--abbrev-commit")) {
-                               revs->abbrev_commit = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--full-diff")) {
-                               revs->diff = 1;
-                               revs->full_diff = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--full-history")) {
-                               revs->simplify_history = 0;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--relative-date")) {
-                               revs->date_mode = DATE_RELATIVE;
-                               continue;
-                       }
-                       if (!strncmp(arg, "--date=", 7)) {
-                               revs->date_mode = parse_date_format(arg + 7);
-                               continue;
-                       }
-                       if (!strcmp(arg, "--log-size")) {
-                               revs->show_log_size = 1;
-                               continue;
-                       }
-
-                       /*
-                        * Grepping the commit log
-                        */
-                       if (!prefixcmp(arg, "--author=")) {
-                               add_header_grep(revs, "author", arg+9);
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--committer=")) {
-                               add_header_grep(revs, "committer", arg+12);
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--grep=")) {
-                               add_message_grep(revs, arg+7);
-                               continue;
-                       }
-                       if (!strcmp(arg, "--extended-regexp") ||
-                           !strcmp(arg, "-E")) {
-                               regflags |= REG_EXTENDED;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--regexp-ignore-case") ||
-                           !strcmp(arg, "-i")) {
-                               regflags |= REG_ICASE;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--fixed-strings") ||
-                           !strcmp(arg, "-F")) {
-                               fixed = 1;
-                               continue;
-                       }
-                       if (!strcmp(arg, "--all-match")) {
-                               all_match = 1;
-                               continue;
-                       }
-                       if (!prefixcmp(arg, "--encoding=")) {
-                               arg += 11;
-                               if (strcmp(arg, "none"))
-                                       git_log_output_encoding = xstrdup(arg);
-                               else
-                                       git_log_output_encoding = "";
-                               continue;
-                       }
-                       if (!strcmp(arg, "--reverse")) {
-                               revs->reverse ^= 1;
-                               continue;
-                       }
                        if (!strcmp(arg, "--no-walk")) {
                                revs->no_walk = 1;
                                continue;
@@ -1311,13 +1285,13 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
                                continue;
                        }
 
-                       opts = diff_opt_parse(&revs->diffopt, argv+i, argc-i);
+                       opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
                        if (opts > 0) {
                                i += opts - 1;
                                continue;
                        }
-                       *unrecognized++ = arg;
-                       left++;
+                       if (opts < 0)
+                               exit(128);
                        continue;
                }
 
@@ -1341,21 +1315,18 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
                }
        }
 
-       if (revs->grep_filter) {
-               revs->grep_filter->regflags |= regflags;
-               revs->grep_filter->fixed = fixed;
-       }
-
-       if (show_merge)
+       if (revs->def == NULL)
+               revs->def = def;
+       if (revs->show_merge)
                prepare_show_merge(revs);
-       if (def && !revs->pending.nr) {
+       if (revs->def && !revs->pending.nr) {
                unsigned char sha1[20];
                struct object *object;
                unsigned mode;
-               if (get_sha1_with_mode(def, sha1, &mode))
-                       die("bad default revision '%s'", def);
-               object = get_reference(revs, def, sha1, 0);
-               add_pending_object_with_mode(revs, object, def, mode);
+               if (get_sha1_with_mode(revs->def, sha1, &mode))
+                       die("bad default revision '%s'", revs->def);
+               object = get_reference(revs, revs->def, sha1, 0);
+               add_pending_object_with_mode(revs, object, revs->def, mode);
        }
 
        /* Did the user ask for any diff output? Run the diff! */
@@ -1388,17 +1359,218 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
        if (diff_setup_done(&revs->diffopt) < 0)
                die("diff_setup_done failed");
 
-       if (revs->grep_filter) {
-               revs->grep_filter->all_match = all_match;
-               compile_grep_patterns(revs->grep_filter);
-       }
+       compile_grep_patterns(&revs->grep_filter);
 
        if (revs->reverse && revs->reflog_info)
                die("cannot combine --reverse with --walk-reflogs");
+       if (revs->rewrite_parents && revs->children.name)
+               die("cannot combine --parents and --children");
+
+       /*
+        * Limitations on the graph functionality
+        */
+       if (revs->reverse && revs->graph)
+               die("cannot combine --reverse with --graph");
+
+       if (revs->reflog_info && revs->graph)
+               die("cannot combine --walk-reflogs with --graph");
 
        return left;
 }
 
+static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
+{
+       struct commit_list *l = xcalloc(1, sizeof(*l));
+
+       l->item = child;
+       l->next = add_decoration(&revs->children, &parent->object, l);
+}
+
+static int remove_duplicate_parents(struct commit *commit)
+{
+       struct commit_list **pp, *p;
+       int surviving_parents;
+
+       /* Examine existing parents while marking ones we have seen... */
+       pp = &commit->parents;
+       while ((p = *pp) != NULL) {
+               struct commit *parent = p->item;
+               if (parent->object.flags & TMP_MARK) {
+                       *pp = p->next;
+                       continue;
+               }
+               parent->object.flags |= TMP_MARK;
+               pp = &p->next;
+       }
+       /* count them while clearing the temporary mark */
+       surviving_parents = 0;
+       for (p = commit->parents; p; p = p->next) {
+               p->item->object.flags &= ~TMP_MARK;
+               surviving_parents++;
+       }
+       return surviving_parents;
+}
+
+struct merge_simplify_state {
+       struct commit *simplified;
+};
+
+static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
+{
+       struct merge_simplify_state *st;
+
+       st = lookup_decoration(&revs->merge_simplification, &commit->object);
+       if (!st) {
+               st = xcalloc(1, sizeof(*st));
+               add_decoration(&revs->merge_simplification, &commit->object, st);
+       }
+       return st;
+}
+
+static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
+{
+       struct commit_list *p;
+       struct merge_simplify_state *st, *pst;
+       int cnt;
+
+       st = locate_simplify_state(revs, commit);
+
+       /*
+        * Have we handled this one?
+        */
+       if (st->simplified)
+               return tail;
+
+       /*
+        * An UNINTERESTING commit simplifies to itself, so does a
+        * root commit.  We do not rewrite parents of such commit
+        * anyway.
+        */
+       if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
+               st->simplified = commit;
+               return tail;
+       }
+
+       /*
+        * Do we know what commit all of our parents should be rewritten to?
+        * Otherwise we are not ready to rewrite this one yet.
+        */
+       for (cnt = 0, p = commit->parents; p; p = p->next) {
+               pst = locate_simplify_state(revs, p->item);
+               if (!pst->simplified) {
+                       tail = &commit_list_insert(p->item, tail)->next;
+                       cnt++;
+               }
+       }
+       if (cnt) {
+               tail = &commit_list_insert(commit, tail)->next;
+               return tail;
+       }
+
+       /*
+        * Rewrite our list of parents.
+        */
+       for (p = commit->parents; p; p = p->next) {
+               pst = locate_simplify_state(revs, p->item);
+               p->item = pst->simplified;
+       }
+       cnt = remove_duplicate_parents(commit);
+
+       /*
+        * It is possible that we are a merge and one side branch
+        * does not have any commit that touches the given paths;
+        * in such a case, the immediate parents will be rewritten
+        * to different commits.
+        *
+        *      o----X          X: the commit we are looking at;
+        *     /    /           o: a commit that touches the paths;
+        * ---o----'
+        *
+        * Further reduce the parents by removing redundant parents.
+        */
+       if (1 < cnt) {
+               struct commit_list *h = reduce_heads(commit->parents);
+               cnt = commit_list_count(h);
+               free_commit_list(commit->parents);
+               commit->parents = h;
+       }
+
+       /*
+        * A commit simplifies to itself if it is a root, if it is
+        * UNINTERESTING, if it touches the given paths, or if it is a
+        * merge and its parents simplifies to more than one commits
+        * (the first two cases are already handled at the beginning of
+        * this function).
+        *
+        * Otherwise, it simplifies to what its sole parent simplifies to.
+        */
+       if (!cnt ||
+           (commit->object.flags & UNINTERESTING) ||
+           !(commit->object.flags & TREESAME) ||
+           (1 < cnt))
+               st->simplified = commit;
+       else {
+               pst = locate_simplify_state(revs, commit->parents->item);
+               st->simplified = pst->simplified;
+       }
+       return tail;
+}
+
+static void simplify_merges(struct rev_info *revs)
+{
+       struct commit_list *list;
+       struct commit_list *yet_to_do, **tail;
+
+       if (!revs->topo_order)
+               sort_in_topological_order(&revs->commits, revs->lifo);
+       if (!revs->prune)
+               return;
+
+       /* feed the list reversed */
+       yet_to_do = NULL;
+       for (list = revs->commits; list; list = list->next)
+               commit_list_insert(list->item, &yet_to_do);
+       while (yet_to_do) {
+               list = yet_to_do;
+               yet_to_do = NULL;
+               tail = &yet_to_do;
+               while (list) {
+                       struct commit *commit = list->item;
+                       struct commit_list *next = list->next;
+                       free(list);
+                       list = next;
+                       tail = simplify_one(revs, commit, tail);
+               }
+       }
+
+       /* clean up the result, removing the simplified ones */
+       list = revs->commits;
+       revs->commits = NULL;
+       tail = &revs->commits;
+       while (list) {
+               struct commit *commit = list->item;
+               struct commit_list *next = list->next;
+               struct merge_simplify_state *st;
+               free(list);
+               list = next;
+               st = locate_simplify_state(revs, commit);
+               if (st->simplified == commit)
+                       tail = &commit_list_insert(commit, tail)->next;
+       }
+}
+
+static void set_children(struct rev_info *revs)
+{
+       struct commit_list *l;
+       for (l = revs->commits; l; l = l->next) {
+               struct commit *commit = l->item;
+               struct commit_list *p;
+
+               for (p = commit->parents; p; p = p->next)
+                       add_child(revs, p->item, commit);
+       }
+}
+
 int prepare_revision_walk(struct rev_info *revs)
 {
        int nr = revs->pending.nr;
@@ -1427,6 +1599,10 @@ int prepare_revision_walk(struct rev_info *revs)
                        return -1;
        if (revs->topo_order)
                sort_in_topological_order(&revs->commits, revs->lifo);
+       if (revs->simplify_merges)
+               simplify_merges(revs);
+       if (revs->children.name)
+               set_children(revs);
        return 0;
 }
 
@@ -1438,10 +1614,12 @@ enum rewrite_result {
 
 static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
 {
+       struct commit_list *cache = NULL;
+
        for (;;) {
                struct commit *p = *pp;
                if (!revs->limited)
-                       if (add_parents_to_list(revs, p, &revs->commits) < 0)
+                       if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
                                return rewrite_one_error;
                if (p->parents && p->parents->next)
                        return rewrite_one_ok;
@@ -1455,26 +1633,6 @@ static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp
        }
 }
 
-static void remove_duplicate_parents(struct commit *commit)
-{
-       struct commit_list **pp, *p;
-
-       /* Examine existing parents while marking ones we have seen... */
-       pp = &commit->parents;
-       while ((p = *pp) != NULL) {
-               struct commit *parent = p->item;
-               if (parent->object.flags & TMP_MARK) {
-                       *pp = p->next;
-                       continue;
-               }
-               parent->object.flags |= TMP_MARK;
-               pp = &p->next;
-       }
-       /* ... and clear the temporary mark */
-       for (p = commit->parents; p; p = p->next)
-               p->item->object.flags &= ~TMP_MARK;
-}
-
 static int rewrite_parents(struct rev_info *revs, struct commit *commit)
 {
        struct commit_list **pp = &commit->parents;
@@ -1497,18 +1655,23 @@ static int rewrite_parents(struct rev_info *revs, struct commit *commit)
 
 static int commit_match(struct commit *commit, struct rev_info *opt)
 {
-       if (!opt->grep_filter)
+       if (!opt->grep_filter.pattern_list)
                return 1;
-       return grep_buffer(opt->grep_filter,
+       return grep_buffer(&opt->grep_filter,
                           NULL, /* we say nothing, not even filename */
                           commit->buffer, strlen(commit->buffer));
 }
 
+static inline int want_ancestry(struct rev_info *revs)
+{
+       return (revs->rewrite_parents || revs->children.name);
+}
+
 enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
 {
        if (commit->object.flags & SHOWN)
                return commit_ignore;
-       if (revs->unpacked && has_sha1_pack(commit->object.sha1, revs->ignore_packed))
+       if (revs->unpacked && has_sha1_pack(commit->object.sha1))
                return commit_ignore;
        if (revs->show_all)
                return commit_show;
@@ -1524,13 +1687,13 @@ enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
                /* Commit without changes? */
                if (commit->object.flags & TREESAME) {
                        /* drop merges unless we want parenthood */
-                       if (!revs->parents)
+                       if (!want_ancestry(revs))
                                return commit_ignore;
                        /* non-merge - always ignore it */
                        if (!commit->parents || !commit->parents->next)
                                return commit_ignore;
                }
-               if (revs->parents && rewrite_parents(revs, commit) < 0)
+               if (want_ancestry(revs) && rewrite_parents(revs, commit) < 0)
                        return commit_error;
        }
        return commit_show;
@@ -1560,15 +1723,17 @@ static struct commit *get_revision_1(struct rev_info *revs)
                        if (revs->max_age != -1 &&
                            (commit->date < revs->max_age))
                                continue;
-                       if (add_parents_to_list(revs, commit, &revs->commits) < 0)
-                               return NULL;
+                       if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0)
+                               die("Failed to traverse parents of commit %s",
+                                   sha1_to_hex(commit->object.sha1));
                }
 
                switch (simplify_commit(revs, commit)) {
                case commit_ignore:
                        continue;
                case commit_error:
-                       return NULL;
+                       die("Failed to simplify parents of commit %s",
+                           sha1_to_hex(commit->object.sha1));
                default:
                        return commit;
                }
@@ -1597,49 +1762,63 @@ static void gc_boundary(struct object_array *array)
        }
 }
 
-struct commit *get_revision(struct rev_info *revs)
+static void create_boundary_commit_list(struct rev_info *revs)
 {
-       struct commit *c = NULL;
-       struct commit_list *l;
+       unsigned i;
+       struct commit *c;
+       struct object_array *array = &revs->boundary_commits;
+       struct object_array_entry *objects = array->objects;
 
-       if (revs->boundary == 2) {
-               unsigned i;
-               struct object_array *array = &revs->boundary_commits;
-               struct object_array_entry *objects = array->objects;
-               for (i = 0; i < array->nr; i++) {
-                       c = (struct commit *)(objects[i].item);
-                       if (!c)
-                               continue;
-                       if (!(c->object.flags & CHILD_SHOWN))
-                               continue;
-                       if (!(c->object.flags & SHOWN))
-                               break;
-               }
-               if (array->nr <= i)
-                       return NULL;
+       /*
+        * If revs->commits is non-NULL at this point, an error occurred in
+        * get_revision_1().  Ignore the error and continue printing the
+        * boundary commits anyway.  (This is what the code has always
+        * done.)
+        */
+       if (revs->commits) {
+               free_commit_list(revs->commits);
+               revs->commits = NULL;
+       }
 
-               c->object.flags |= SHOWN | BOUNDARY;
-               return c;
+       /*
+        * Put all of the actual boundary commits from revs->boundary_commits
+        * into revs->commits
+        */
+       for (i = 0; i < array->nr; i++) {
+               c = (struct commit *)(objects[i].item);
+               if (!c)
+                       continue;
+               if (!(c->object.flags & CHILD_SHOWN))
+                       continue;
+               if (c->object.flags & (SHOWN | BOUNDARY))
+                       continue;
+               c->object.flags |= BOUNDARY;
+               commit_list_insert(c, &revs->commits);
        }
 
-       if (revs->reverse) {
-               int limit = -1;
+       /*
+        * If revs->topo_order is set, sort the boundary commits
+        * in topological order
+        */
+       sort_in_topological_order(&revs->commits, revs->lifo);
+}
 
-               if (0 <= revs->max_count) {
-                       limit = revs->max_count;
-                       if (0 < revs->skip_count)
-                               limit += revs->skip_count;
-               }
-               l = NULL;
-               while ((c = get_revision_1(revs))) {
-                       commit_list_insert(c, &l);
-                       if ((0 < limit) && !--limit)
-                               break;
-               }
-               revs->commits = l;
-               revs->reverse = 0;
-               revs->max_count = -1;
-               c = NULL;
+static struct commit *get_revision_internal(struct rev_info *revs)
+{
+       struct commit *c = NULL;
+       struct commit_list *l;
+
+       if (revs->boundary == 2) {
+               /*
+                * All of the normal commits have already been returned,
+                * and we are now returning boundary commits.
+                * create_boundary_commit_list() has populated
+                * revs->commits with the remaining commits to return.
+                */
+               c = pop_commit(&revs->commits);
+               if (c)
+                       c->object.flags |= SHOWN;
+               return c;
        }
 
        /*
@@ -1682,7 +1861,14 @@ struct commit *get_revision(struct rev_info *revs)
                 * switch to boundary commits output mode.
                 */
                revs->boundary = 2;
-               return get_revision(revs);
+
+               /*
+                * Update revs->commits to contain the list of
+                * boundary commits.
+                */
+               create_boundary_commit_list(revs);
+
+               return get_revision_internal(revs);
        }
 
        /*
@@ -1704,3 +1890,27 @@ struct commit *get_revision(struct rev_info *revs)
 
        return c;
 }
+
+struct commit *get_revision(struct rev_info *revs)
+{
+       struct commit *c;
+       struct commit_list *reversed;
+
+       if (revs->reverse) {
+               reversed = NULL;
+               while ((c = get_revision_internal(revs))) {
+                       commit_list_insert(c, &reversed);
+               }
+               revs->commits = reversed;
+               revs->reverse = 0;
+               revs->reverse_output_stage = 1;
+       }
+
+       if (revs->reverse_output_stage)
+               return pop_commit(&revs->commits);
+
+       c = get_revision_internal(revs);
+       if (c && revs->graph)
+               graph_update(revs->graph, c);
+       return c;
+}