merge-recursive: remove final remaining caller of merge_file_one()
[gitweb.git] / commit.c
index 23db654d64b8d3c10c21988f12b449d1d5bcbec5..d0f199e12286983c3f9f23b6567dc78a2ceeaf79 100644 (file)
--- a/commit.c
+++ b/commit.c
@@ -2,17 +2,21 @@
 #include "tag.h"
 #include "commit.h"
 #include "commit-graph.h"
+#include "repository.h"
+#include "object-store.h"
 #include "pkt-line.h"
 #include "utf8.h"
 #include "diff.h"
 #include "revision.h"
 #include "notes.h"
+#include "alloc.h"
 #include "gpg-interface.h"
 #include "mergesort.h"
 #include "commit-slab.h"
 #include "prio-queue.h"
 #include "sha1-lookup.h"
 #include "wt-status.h"
+#include "advice.h"
 
 static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
 
@@ -20,39 +24,42 @@ int save_commit_buffer = 1;
 
 const char *commit_type = "commit";
 
-struct commit *lookup_commit_reference_gently(const struct object_id *oid,
-                                             int quiet)
+struct commit *lookup_commit_reference_gently(struct repository *r,
+               const struct object_id *oid, int quiet)
 {
-       struct object *obj = deref_tag(parse_object(oid), NULL, 0);
+       struct object *obj = deref_tag(r,
+                                      parse_object(r, oid),
+                                      NULL, 0);
 
        if (!obj)
                return NULL;
-       return object_as_type(obj, OBJ_COMMIT, quiet);
+       return object_as_type(r, obj, OBJ_COMMIT, quiet);
 }
 
-struct commit *lookup_commit_reference(const struct object_id *oid)
+struct commit *lookup_commit_reference(struct repository *r, const struct object_id *oid)
 {
-       return lookup_commit_reference_gently(oid, 0);
+       return lookup_commit_reference_gently(r, oid, 0);
 }
 
 struct commit *lookup_commit_or_die(const struct object_id *oid, const char *ref_name)
 {
-       struct commit *c = lookup_commit_reference(oid);
+       struct commit *c = lookup_commit_reference(the_repository, oid);
        if (!c)
                die(_("could not parse %s"), ref_name);
-       if (oidcmp(oid, &c->object.oid)) {
+       if (!oideq(oid, &c->object.oid)) {
                warning(_("%s %s is not a commit!"),
                        ref_name, oid_to_hex(oid));
        }
        return c;
 }
 
-struct commit *lookup_commit(const struct object_id *oid)
+struct commit *lookup_commit(struct repository *r, const struct object_id *oid)
 {
-       struct object *obj = lookup_object(oid->hash);
+       struct object *obj = lookup_object(r, oid->hash);
        if (!obj)
-               return create_object(oid->hash, alloc_commit_node());
-       return object_as_type(obj, OBJ_COMMIT, 0);
+               return create_object(r, oid->hash,
+                                    alloc_commit_node(r));
+       return object_as_type(r, obj, OBJ_COMMIT, 0);
 }
 
 struct commit *lookup_commit_reference_by_name(const char *name)
@@ -62,7 +69,7 @@ struct commit *lookup_commit_reference_by_name(const char *name)
 
        if (get_oid_committish(name, &oid))
                return NULL;
-       commit = lookup_commit_reference(&oid);
+       commit = lookup_commit_reference(the_repository, &oid);
        if (parse_commit(commit))
                return NULL;
        return commit;
@@ -95,41 +102,44 @@ static timestamp_t parse_commit_date(const char *buf, const char *tail)
        return parse_timestamp(dateptr, NULL, 10);
 }
 
-static struct commit_graft **commit_graft;
-static int commit_graft_alloc, commit_graft_nr;
-
 static const unsigned char *commit_graft_sha1_access(size_t index, void *table)
 {
        struct commit_graft **commit_graft_table = table;
        return commit_graft_table[index]->oid.hash;
 }
 
-static int commit_graft_pos(const unsigned char *sha1)
+static int commit_graft_pos(struct repository *r, const unsigned char *sha1)
 {
-       return sha1_pos(sha1, commit_graft, commit_graft_nr,
+       return sha1_pos(sha1, r->parsed_objects->grafts,
+                       r->parsed_objects->grafts_nr,
                        commit_graft_sha1_access);
 }
 
-int register_commit_graft(struct commit_graft *graft, int ignore_dups)
+int register_commit_graft(struct repository *r, struct commit_graft *graft,
+                         int ignore_dups)
 {
-       int pos = commit_graft_pos(graft->oid.hash);
+       int pos = commit_graft_pos(r, graft->oid.hash);
 
        if (0 <= pos) {
                if (ignore_dups)
                        free(graft);
                else {
-                       free(commit_graft[pos]);
-                       commit_graft[pos] = graft;
+                       free(r->parsed_objects->grafts[pos]);
+                       r->parsed_objects->grafts[pos] = graft;
                }
                return 1;
        }
        pos = -pos - 1;
-       ALLOC_GROW(commit_graft, commit_graft_nr + 1, commit_graft_alloc);
-       commit_graft_nr++;
-       if (pos < commit_graft_nr)
-               MOVE_ARRAY(commit_graft + pos + 1, commit_graft + pos,
-                          commit_graft_nr - pos - 1);
-       commit_graft[pos] = graft;
+       ALLOC_GROW(r->parsed_objects->grafts,
+                  r->parsed_objects->grafts_nr + 1,
+                  r->parsed_objects->grafts_alloc);
+       r->parsed_objects->grafts_nr++;
+       if (pos < r->parsed_objects->grafts_nr)
+               memmove(r->parsed_objects->grafts + pos + 1,
+                       r->parsed_objects->grafts + pos,
+                       (r->parsed_objects->grafts_nr - pos - 1) *
+                       sizeof(*r->parsed_objects->grafts));
+       r->parsed_objects->grafts[pos] = graft;
        return 0;
 }
 
@@ -171,18 +181,27 @@ struct commit_graft *read_graft_line(struct strbuf *line)
        return NULL;
 }
 
-static int read_graft_file(const char *graft_file)
+static int read_graft_file(struct repository *r, const char *graft_file)
 {
        FILE *fp = fopen_or_warn(graft_file, "r");
        struct strbuf buf = STRBUF_INIT;
        if (!fp)
                return -1;
+       if (advice_graft_file_deprecated)
+               advise(_("Support for <GIT_DIR>/info/grafts is deprecated\n"
+                        "and will be removed in a future Git version.\n"
+                        "\n"
+                        "Please use \"git replace --convert-graft-file\"\n"
+                        "to convert the grafts into replace refs.\n"
+                        "\n"
+                        "Turn this message off by running\n"
+                        "\"git config advice.graftFileDeprecated false\""));
        while (!strbuf_getwholeline(&buf, fp, '\n')) {
                /* The format is just "Commit Parent1 Parent2 ...\n" */
                struct commit_graft *graft = read_graft_line(&buf);
                if (!graft)
                        continue;
-               if (register_commit_graft(graft, 1))
+               if (register_commit_graft(r, graft, 1))
                        error("duplicate graft data: %s", buf.buf);
        }
        fclose(fp);
@@ -190,47 +209,50 @@ static int read_graft_file(const char *graft_file)
        return 0;
 }
 
-static void prepare_commit_graft(void)
+static void prepare_commit_graft(struct repository *r)
 {
-       static int commit_graft_prepared;
        char *graft_file;
 
-       if (commit_graft_prepared)
+       if (r->parsed_objects->commit_graft_prepared)
+               return;
+       if (!startup_info->have_repository)
                return;
-       graft_file = get_graft_file();
-       read_graft_file(graft_file);
+
+       graft_file = get_graft_file(r);
+       read_graft_file(r, graft_file);
        /* make sure shallows are read */
-       is_repository_shallow();
-       commit_graft_prepared = 1;
+       is_repository_shallow(r);
+       r->parsed_objects->commit_graft_prepared = 1;
 }
 
-struct commit_graft *lookup_commit_graft(const struct object_id *oid)
+struct commit_graft *lookup_commit_graft(struct repository *r, const struct object_id *oid)
 {
        int pos;
-       prepare_commit_graft();
-       pos = commit_graft_pos(oid->hash);
+       prepare_commit_graft(r);
+       pos = commit_graft_pos(r, oid->hash);
        if (pos < 0)
                return NULL;
-       return commit_graft[pos];
+       return r->parsed_objects->grafts[pos];
 }
 
 int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
 {
        int i, ret;
-       for (i = ret = 0; i < commit_graft_nr && !ret; i++)
-               ret = fn(commit_graft[i], cb_data);
+       for (i = ret = 0; i < the_repository->parsed_objects->grafts_nr && !ret; i++)
+               ret = fn(the_repository->parsed_objects->grafts[i], cb_data);
        return ret;
 }
 
 int unregister_shallow(const struct object_id *oid)
 {
-       int pos = commit_graft_pos(oid->hash);
+       int pos = commit_graft_pos(the_repository, oid->hash);
        if (pos < 0)
                return -1;
-       if (pos + 1 < commit_graft_nr)
-               MOVE_ARRAY(commit_graft + pos, commit_graft + pos + 1,
-                          commit_graft_nr - pos - 1);
-       commit_graft_nr--;
+       if (pos + 1 < the_repository->parsed_objects->grafts_nr)
+               MOVE_ARRAY(the_repository->parsed_objects->grafts + pos,
+                          the_repository->parsed_objects->grafts + pos + 1,
+                          the_repository->parsed_objects->grafts_nr - pos - 1);
+       the_repository->parsed_objects->grafts_nr--;
        return 0;
 }
 
@@ -239,18 +261,32 @@ struct commit_buffer {
        unsigned long size;
 };
 define_commit_slab(buffer_slab, struct commit_buffer);
-static struct buffer_slab buffer_slab = COMMIT_SLAB_INIT(1, buffer_slab);
 
-void set_commit_buffer(struct commit *commit, void *buffer, unsigned long size)
+struct buffer_slab *allocate_commit_buffer_slab(void)
+{
+       struct buffer_slab *bs = xmalloc(sizeof(*bs));
+       init_buffer_slab(bs);
+       return bs;
+}
+
+void free_commit_buffer_slab(struct buffer_slab *bs)
 {
-       struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
+       clear_buffer_slab(bs);
+       free(bs);
+}
+
+void set_commit_buffer(struct repository *r, struct commit *commit, void *buffer, unsigned long size)
+{
+       struct commit_buffer *v = buffer_slab_at(
+               r->parsed_objects->buffer_slab, commit);
        v->buffer = buffer;
        v->size = size;
 }
 
-const void *get_cached_commit_buffer(const struct commit *commit, unsigned long *sizep)
+const void *get_cached_commit_buffer(struct repository *r, const struct commit *commit, unsigned long *sizep)
 {
-       struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
+       struct commit_buffer *v = buffer_slab_peek(
+               r->parsed_objects->buffer_slab, commit);
        if (!v) {
                if (sizep)
                        *sizep = 0;
@@ -263,11 +299,11 @@ const void *get_cached_commit_buffer(const struct commit *commit, unsigned long
 
 const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
 {
-       const void *ret = get_cached_commit_buffer(commit, sizep);
+       const void *ret = get_cached_commit_buffer(the_repository, commit, sizep);
        if (!ret) {
                enum object_type type;
                unsigned long size;
-               ret = read_sha1_file(commit->object.oid.hash, &type, &size);
+               ret = read_object_file(&commit->object.oid, &type, &size);
                if (!ret)
                        die("cannot read commit object %s",
                            oid_to_hex(&commit->object.oid));
@@ -282,14 +318,16 @@ const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
 
 void unuse_commit_buffer(const struct commit *commit, const void *buffer)
 {
-       struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
+       struct commit_buffer *v = buffer_slab_peek(
+               the_repository->parsed_objects->buffer_slab, commit);
        if (!(v && v->buffer == buffer))
                free((void *)buffer);
 }
 
 void free_commit_buffer(struct commit *commit)
 {
-       struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
+       struct commit_buffer *v = buffer_slab_peek(
+               the_repository->parsed_objects->buffer_slab, commit);
        if (v) {
                FREE_AND_NULL(v->buffer);
                v->size = 0;
@@ -304,7 +342,7 @@ struct tree *get_commit_tree(const struct commit *commit)
        if (commit->graph_pos == COMMIT_NOT_FROM_GRAPH)
                BUG("commit has NULL tree, but was not loaded from commit-graph");
 
-       return get_commit_tree_in_graph(commit);
+       return get_commit_tree_in_graph(the_repository, commit);
 }
 
 struct object_id *get_commit_tree_oid(const struct commit *commit)
@@ -312,9 +350,21 @@ struct object_id *get_commit_tree_oid(const struct commit *commit)
        return &get_commit_tree(commit)->object.oid;
 }
 
+void release_commit_memory(struct commit *c)
+{
+       c->maybe_tree = NULL;
+       c->index = 0;
+       free_commit_buffer(c);
+       free_commit_list(c->parents);
+       /* TODO: what about commit->util? */
+
+       c->object.parsed = 0;
+}
+
 const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
 {
-       struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
+       struct commit_buffer *v = buffer_slab_peek(
+               the_repository->parsed_objects->buffer_slab, commit);
        void *ret;
 
        if (!v) {
@@ -331,15 +381,15 @@ const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
        return ret;
 }
 
-int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size, int check_graph)
+int parse_commit_buffer(struct repository *r, struct commit *item, const void *buffer, unsigned long size, int check_graph)
 {
        const char *tail = buffer;
        const char *bufptr = buffer;
        struct object_id parent;
        struct commit_list **pptr;
        struct commit_graft *graft;
-       const int tree_entry_len = GIT_SHA1_HEXSZ + 5;
-       const int parent_entry_len = GIT_SHA1_HEXSZ + 7;
+       const int tree_entry_len = the_hash_algo->hexsz + 5;
+       const int parent_entry_len = the_hash_algo->hexsz + 7;
 
        if (item->object.parsed)
                return 0;
@@ -348,19 +398,19 @@ int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long s
        if (tail <= bufptr + tree_entry_len + 1 || memcmp(bufptr, "tree ", 5) ||
                        bufptr[tree_entry_len] != '\n')
                return error("bogus commit object %s", oid_to_hex(&item->object.oid));
-       if (get_sha1_hex(bufptr + 5, parent.hash) < 0)
+       if (get_oid_hex(bufptr + 5, &parent) < 0)
                return error("bad tree pointer in commit %s",
                             oid_to_hex(&item->object.oid));
-       item->maybe_tree = lookup_tree(&parent);
+       item->maybe_tree = lookup_tree(r, &parent);
        bufptr += tree_entry_len + 1; /* "tree " + "hex sha1" + "\n" */
        pptr = &item->parents;
 
-       graft = lookup_commit_graft(&item->object.oid);
+       graft = lookup_commit_graft(r, &item->object.oid);
        while (bufptr + parent_entry_len < tail && !memcmp(bufptr, "parent ", 7)) {
                struct commit *new_parent;
 
                if (tail <= bufptr + parent_entry_len + 1 ||
-                   get_sha1_hex(bufptr + 7, parent.hash) ||
+                   get_oid_hex(bufptr + 7, &parent) ||
                    bufptr[parent_entry_len] != '\n')
                        return error("bad parents in commit %s", oid_to_hex(&item->object.oid));
                bufptr += parent_entry_len + 1;
@@ -370,7 +420,7 @@ int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long s
                 */
                if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
                        continue;
-               new_parent = lookup_commit(&parent);
+               new_parent = lookup_commit(r, &parent);
                if (new_parent)
                        pptr = &commit_list_insert(new_parent, pptr)->next;
        }
@@ -378,7 +428,8 @@ int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long s
                int i;
                struct commit *new_parent;
                for (i = 0; i < graft->nr_parent; i++) {
-                       new_parent = lookup_commit(&graft->parent[i]);
+                       new_parent = lookup_commit(r,
+                                                  &graft->parent[i]);
                        if (!new_parent)
                                continue;
                        pptr = &commit_list_insert(new_parent, pptr)->next;
@@ -387,12 +438,12 @@ int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long s
        item->date = parse_commit_date(bufptr, tail);
 
        if (check_graph)
-               load_commit_graph_info(item);
+               load_commit_graph_info(the_repository, item);
 
        return 0;
 }
 
-int parse_commit_gently(struct commit *item, int quiet_on_missing)
+int parse_commit_internal(struct commit *item, int quiet_on_missing, int use_commit_graph)
 {
        enum object_type type;
        void *buffer;
@@ -403,9 +454,9 @@ int parse_commit_gently(struct commit *item, int quiet_on_missing)
                return -1;
        if (item->object.parsed)
                return 0;
-       if (parse_commit_in_graph(item))
+       if (use_commit_graph && parse_commit_in_graph(the_repository, item))
                return 0;
-       buffer = read_sha1_file(item->object.oid.hash, &type, &size);
+       buffer = read_object_file(&item->object.oid, &type, &size);
        if (!buffer)
                return quiet_on_missing ? -1 :
                        error("Could not read %s",
@@ -415,15 +466,21 @@ int parse_commit_gently(struct commit *item, int quiet_on_missing)
                return error("Object %s not a commit",
                             oid_to_hex(&item->object.oid));
        }
-       ret = parse_commit_buffer(item, buffer, size, 0);
+
+       ret = parse_commit_buffer(the_repository, item, buffer, size, 0);
        if (save_commit_buffer && !ret) {
-               set_commit_buffer(item, buffer, size);
+               set_commit_buffer(the_repository, item, buffer, size);
                return 0;
        }
        free(buffer);
        return ret;
 }
 
+int parse_commit_gently(struct commit *item, int quiet_on_missing)
+{
+       return parse_commit_internal(item, quiet_on_missing, 1);
+}
+
 void parse_commit_or_die(struct commit *item)
 {
        if (parse_commit(item))
@@ -599,7 +656,7 @@ struct commit *pop_commit(struct commit_list **stack)
 define_commit_slab(indegree_slab, int);
 
 /* record author-date for each commit object */
-define_commit_slab(author_date_slab, unsigned long);
+define_commit_slab(author_date_slab, timestamp_t);
 
 static void record_author_date(struct author_date_slab *author_date,
                               struct commit *commit)
@@ -786,367 +843,6 @@ void sort_in_topological_order(struct commit_list **list, enum rev_sort_order so
                clear_author_date_slab(&author_date);
 }
 
-/* merge-base stuff */
-
-/* Remember to update object flag allocation in object.h */
-#define PARENT1                (1u<<16)
-#define PARENT2                (1u<<17)
-#define STALE          (1u<<18)
-#define RESULT         (1u<<19)
-
-static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
-
-static int queue_has_nonstale(struct prio_queue *queue)
-{
-       int i;
-       for (i = 0; i < queue->nr; i++) {
-               struct commit *commit = queue->array[i].data;
-               if (!(commit->object.flags & STALE))
-                       return 1;
-       }
-       return 0;
-}
-
-/* all input commits in one and twos[] must have been parsed! */
-static struct commit_list *paint_down_to_common(struct commit *one, int n,
-                                               struct commit **twos,
-                                               int min_generation)
-{
-       struct prio_queue queue = { compare_commits_by_gen_then_commit_date };
-       struct commit_list *result = NULL;
-       int i;
-       uint32_t last_gen = GENERATION_NUMBER_INFINITY;
-
-       if (!min_generation)
-               queue.compare = compare_commits_by_commit_date;
-
-       one->object.flags |= PARENT1;
-       if (!n) {
-               commit_list_append(one, &result);
-               return result;
-       }
-       prio_queue_put(&queue, one);
-
-       for (i = 0; i < n; i++) {
-               twos[i]->object.flags |= PARENT2;
-               prio_queue_put(&queue, twos[i]);
-       }
-
-       while (queue_has_nonstale(&queue)) {
-               struct commit *commit = prio_queue_get(&queue);
-               struct commit_list *parents;
-               int flags;
-
-               if (min_generation && commit->generation > last_gen)
-                       BUG("bad generation skip %8x > %8x at %s",
-                           commit->generation, last_gen,
-                           oid_to_hex(&commit->object.oid));
-               last_gen = commit->generation;
-
-               if (commit->generation < min_generation)
-                       break;
-
-               flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
-               if (flags == (PARENT1 | PARENT2)) {
-                       if (!(commit->object.flags & RESULT)) {
-                               commit->object.flags |= RESULT;
-                               commit_list_insert_by_date(commit, &result);
-                       }
-                       /* Mark parents of a found merge stale */
-                       flags |= STALE;
-               }
-               parents = commit->parents;
-               while (parents) {
-                       struct commit *p = parents->item;
-                       parents = parents->next;
-                       if ((p->object.flags & flags) == flags)
-                               continue;
-                       if (parse_commit(p))
-                               return NULL;
-                       p->object.flags |= flags;
-                       prio_queue_put(&queue, p);
-               }
-       }
-
-       clear_prio_queue(&queue);
-       return result;
-}
-
-static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
-{
-       struct commit_list *list = NULL;
-       struct commit_list *result = NULL;
-       int i;
-
-       for (i = 0; i < n; i++) {
-               if (one == twos[i])
-                       /*
-                        * We do not mark this even with RESULT so we do not
-                        * have to clean it up.
-                        */
-                       return commit_list_insert(one, &result);
-       }
-
-       if (parse_commit(one))
-               return NULL;
-       for (i = 0; i < n; i++) {
-               if (parse_commit(twos[i]))
-                       return NULL;
-       }
-
-       list = paint_down_to_common(one, n, twos, 0);
-
-       while (list) {
-               struct commit *commit = pop_commit(&list);
-               if (!(commit->object.flags & STALE))
-                       commit_list_insert_by_date(commit, &result);
-       }
-       return result;
-}
-
-struct commit_list *get_octopus_merge_bases(struct commit_list *in)
-{
-       struct commit_list *i, *j, *k, *ret = NULL;
-
-       if (!in)
-               return ret;
-
-       commit_list_insert(in->item, &ret);
-
-       for (i = in->next; i; i = i->next) {
-               struct commit_list *new_commits = NULL, *end = NULL;
-
-               for (j = ret; j; j = j->next) {
-                       struct commit_list *bases;
-                       bases = get_merge_bases(i->item, j->item);
-                       if (!new_commits)
-                               new_commits = bases;
-                       else
-                               end->next = bases;
-                       for (k = bases; k; k = k->next)
-                               end = k;
-               }
-               ret = new_commits;
-       }
-       return ret;
-}
-
-static int remove_redundant(struct commit **array, int cnt)
-{
-       /*
-        * Some commit in the array may be an ancestor of
-        * another commit.  Move such commit to the end of
-        * the array, and return the number of commits that
-        * are independent from each other.
-        */
-       struct commit **work;
-       unsigned char *redundant;
-       int *filled_index;
-       int i, j, filled;
-
-       work = xcalloc(cnt, sizeof(*work));
-       redundant = xcalloc(cnt, 1);
-       ALLOC_ARRAY(filled_index, cnt - 1);
-
-       for (i = 0; i < cnt; i++)
-               parse_commit(array[i]);
-       for (i = 0; i < cnt; i++) {
-               struct commit_list *common;
-               uint32_t min_generation = array[i]->generation;
-
-               if (redundant[i])
-                       continue;
-               for (j = filled = 0; j < cnt; j++) {
-                       if (i == j || redundant[j])
-                               continue;
-                       filled_index[filled] = j;
-                       work[filled++] = array[j];
-
-                       if (array[j]->generation < min_generation)
-                               min_generation = array[j]->generation;
-               }
-               common = paint_down_to_common(array[i], filled, work,
-                                             min_generation);
-               if (array[i]->object.flags & PARENT2)
-                       redundant[i] = 1;
-               for (j = 0; j < filled; j++)
-                       if (work[j]->object.flags & PARENT1)
-                               redundant[filled_index[j]] = 1;
-               clear_commit_marks(array[i], all_flags);
-               clear_commit_marks_many(filled, work, all_flags);
-               free_commit_list(common);
-       }
-
-       /* Now collect the result */
-       COPY_ARRAY(work, array, cnt);
-       for (i = filled = 0; i < cnt; i++)
-               if (!redundant[i])
-                       array[filled++] = work[i];
-       for (j = filled, i = 0; i < cnt; i++)
-               if (redundant[i])
-                       array[j++] = work[i];
-       free(work);
-       free(redundant);
-       free(filled_index);
-       return filled;
-}
-
-static struct commit_list *get_merge_bases_many_0(struct commit *one,
-                                                 int n,
-                                                 struct commit **twos,
-                                                 int cleanup)
-{
-       struct commit_list *list;
-       struct commit **rslt;
-       struct commit_list *result;
-       int cnt, i;
-
-       result = merge_bases_many(one, n, twos);
-       for (i = 0; i < n; i++) {
-               if (one == twos[i])
-                       return result;
-       }
-       if (!result || !result->next) {
-               if (cleanup) {
-                       clear_commit_marks(one, all_flags);
-                       clear_commit_marks_many(n, twos, all_flags);
-               }
-               return result;
-       }
-
-       /* There are more than one */
-       cnt = commit_list_count(result);
-       rslt = xcalloc(cnt, sizeof(*rslt));
-       for (list = result, i = 0; list; list = list->next)
-               rslt[i++] = list->item;
-       free_commit_list(result);
-
-       clear_commit_marks(one, all_flags);
-       clear_commit_marks_many(n, twos, all_flags);
-
-       cnt = remove_redundant(rslt, cnt);
-       result = NULL;
-       for (i = 0; i < cnt; i++)
-               commit_list_insert_by_date(rslt[i], &result);
-       free(rslt);
-       return result;
-}
-
-struct commit_list *get_merge_bases_many(struct commit *one,
-                                        int n,
-                                        struct commit **twos)
-{
-       return get_merge_bases_many_0(one, n, twos, 1);
-}
-
-struct commit_list *get_merge_bases_many_dirty(struct commit *one,
-                                              int n,
-                                              struct commit **twos)
-{
-       return get_merge_bases_many_0(one, n, twos, 0);
-}
-
-struct commit_list *get_merge_bases(struct commit *one, struct commit *two)
-{
-       return get_merge_bases_many_0(one, 1, &two, 1);
-}
-
-/*
- * Is "commit" a descendant of one of the elements on the "with_commit" list?
- */
-int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
-{
-       if (!with_commit)
-               return 1;
-       while (with_commit) {
-               struct commit *other;
-
-               other = with_commit->item;
-               with_commit = with_commit->next;
-               if (in_merge_bases(other, commit))
-                       return 1;
-       }
-       return 0;
-}
-
-/*
- * Is "commit" an ancestor of one of the "references"?
- */
-int in_merge_bases_many(struct commit *commit, int nr_reference, struct commit **reference)
-{
-       struct commit_list *bases;
-       int ret = 0, i;
-       uint32_t min_generation = GENERATION_NUMBER_INFINITY;
-
-       if (parse_commit(commit))
-               return ret;
-       for (i = 0; i < nr_reference; i++) {
-               if (parse_commit(reference[i]))
-                       return ret;
-               if (reference[i]->generation < min_generation)
-                       min_generation = reference[i]->generation;
-       }
-
-       if (commit->generation > min_generation)
-               return ret;
-
-       bases = paint_down_to_common(commit, nr_reference, reference, commit->generation);
-       if (commit->object.flags & PARENT2)
-               ret = 1;
-       clear_commit_marks(commit, all_flags);
-       clear_commit_marks_many(nr_reference, reference, all_flags);
-       free_commit_list(bases);
-       return ret;
-}
-
-/*
- * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
- */
-int in_merge_bases(struct commit *commit, struct commit *reference)
-{
-       return in_merge_bases_many(commit, 1, &reference);
-}
-
-struct commit_list *reduce_heads(struct commit_list *heads)
-{
-       struct commit_list *p;
-       struct commit_list *result = NULL, **tail = &result;
-       struct commit **array;
-       int num_head, i;
-
-       if (!heads)
-               return NULL;
-
-       /* Uniquify */
-       for (p = heads; p; p = p->next)
-               p->item->object.flags &= ~STALE;
-       for (p = heads, num_head = 0; p; p = p->next) {
-               if (p->item->object.flags & STALE)
-                       continue;
-               p->item->object.flags |= STALE;
-               num_head++;
-       }
-       array = xcalloc(num_head, sizeof(*array));
-       for (p = heads, i = 0; p; p = p->next) {
-               if (p->item->object.flags & STALE) {
-                       array[i++] = p->item;
-                       p->item->object.flags &= ~STALE;
-               }
-       }
-       num_head = remove_redundant(array, num_head);
-       for (i = 0; i < num_head; i++)
-               tail = &commit_list_insert(array[i], tail)->next;
-       free(array);
-       return result;
-}
-
-void reduce_heads_replace(struct commit_list **heads)
-{
-       struct commit_list *result = reduce_heads(*heads);
-       free_commit_list(*heads);
-       *heads = result;
-}
-
 static const char gpg_sig_header[] = "gpgsig";
 static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1;
 
@@ -1273,7 +969,7 @@ static void handle_signed_tag(struct commit *parent, struct commit_extra_header
        desc = merge_remote_util(parent);
        if (!desc || !desc->obj)
                return;
-       buf = read_sha1_file(desc->obj->oid.hash, &type, &size);
+       buf = read_object_file(&desc->obj->oid, &type, &size);
        if (!buf || type != OBJ_TAG)
                goto free_return;
        len = parse_signature(buf, size);
@@ -1355,17 +1051,19 @@ struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
        return extra;
 }
 
-void for_each_mergetag(each_mergetag_fn fn, struct commit *commit, void *data)
+int for_each_mergetag(each_mergetag_fn fn, struct commit *commit, void *data)
 {
        struct commit_extra_header *extra, *to_free;
+       int res = 0;
 
        to_free = read_commit_extra_headers(commit, NULL);
-       for (extra = to_free; extra; extra = extra->next) {
+       for (extra = to_free; !res && extra; extra = extra->next) {
                if (strcmp(extra->key, "mergetag"))
                        continue; /* not a merge tag */
-               fn(commit, extra, data);
+               res = fn(commit, extra, data);
        }
        free_commit_extra_headers(to_free);
+       return res;
 }
 
 static inline int standard_header_field(const char *field, size_t len)
@@ -1584,7 +1282,7 @@ int commit_tree_extended(const char *msg, size_t msg_len,
        int encoding_is_utf8;
        struct strbuf buffer;
 
-       assert_sha1_type(tree->hash, OBJ_TREE);
+       assert_oid_type(tree, OBJ_TREE);
 
        if (memchr(msg, '\0', msg_len))
                return error("a NUL byte in commit log message not allowed.");
@@ -1638,13 +1336,21 @@ int commit_tree_extended(const char *msg, size_t msg_len,
        return result;
 }
 
+define_commit_slab(merge_desc_slab, struct merge_remote_desc *);
+static struct merge_desc_slab merge_desc_slab = COMMIT_SLAB_INIT(1, merge_desc_slab);
+
+struct merge_remote_desc *merge_remote_util(struct commit *commit)
+{
+       return *merge_desc_slab_at(&merge_desc_slab, commit);
+}
+
 void set_merge_remote_desc(struct commit *commit,
                           const char *name, struct object *obj)
 {
        struct merge_remote_desc *desc;
        FLEX_ALLOC_STR(desc, name, name);
        desc->obj = obj;
-       commit->util = desc;
+       *merge_desc_slab_at(&merge_desc_slab, commit) = desc;
 }
 
 struct commit *get_merge_parent(const char *name)
@@ -1654,9 +1360,9 @@ struct commit *get_merge_parent(const char *name)
        struct object_id oid;
        if (get_oid(name, &oid))
                return NULL;
-       obj = parse_object(&oid);
+       obj = parse_object(the_repository, &oid);
        commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
-       if (commit && !commit->util)
+       if (commit && !merge_remote_util(commit))
                set_merge_remote_desc(commit, name, obj);
        return commit;
 }
@@ -1720,10 +1426,10 @@ const char *find_commit_header(const char *msg, const char *key, size_t *out_len
  * Returns the number of bytes from the tail to ignore, to be fed as
  * the second parameter to append_signoff().
  */
-int ignore_non_trailer(const char *buf, size_t len)
+size_t ignore_non_trailer(const char *buf, size_t len)
 {
-       int boc = 0;
-       int bol = 0;
+       size_t boc = 0;
+       size_t bol = 0;
        int in_old_conflicts_block = 0;
        size_t cutoff = wt_status_locate_end(buf, len);