Merge branch 'ds/reachable'
authorJunio C Hamano <gitster@pobox.com>
Mon, 17 Sep 2018 20:53:52 +0000 (13:53 -0700)
committerJunio C Hamano <gitster@pobox.com>
Mon, 17 Sep 2018 20:53:52 +0000 (13:53 -0700)
The code for computing history reachability has been shuffled,
obtained a bunch of new tests to cover them, and then being
improved.

* ds/reachable:
commit-reach: correct accidental #include of C file
commit-reach: use can_all_from_reach
commit-reach: make can_all_from_reach... linear
commit-reach: replace ref_newer logic
test-reach: test commit_contains
test-reach: test can_all_from_reach_with_flags
test-reach: test reduce_heads
test-reach: test get_merge_bases_many
test-reach: test is_descendant_of
test-reach: test in_merge_bases
test-reach: create new test tool for ref_newer
commit-reach: move can_all_from_reach_with_flags
upload-pack: generalize commit date cutoff
upload-pack: refactor ok_to_give_up()
upload-pack: make reachable() more generic
commit-reach: move commit_contains from ref-filter
commit-reach: move ref_newer from remote.c
commit.h: remove method declarations
commit-reach: move walk methods from commit.c

38 files changed:
Makefile
bisect.c
builtin/branch.c
builtin/commit.c
builtin/fetch.c
builtin/fmt-merge-msg.c
builtin/log.c
builtin/merge-base.c
builtin/merge.c
builtin/pull.c
builtin/receive-pack.c
builtin/remote.c
builtin/rev-parse.c
commit-graph.c
commit-graph.h
commit-reach.c [new file with mode: 0644]
commit-reach.h [new file with mode: 0644]
commit.c
commit.h
fast-import.c
http-push.c
merge-recursive.c
notes-merge.c
object.h
pack-bitmap-write.c
ref-filter.c
remote.c
remote.h
revision.c
sequencer.c
sha1-name.c
shallow.c
submodule.c
t/helper/test-reach.c [new file with mode: 0644]
t/helper/test-tool.c
t/helper/test-tool.h
t/t6600-test-reach.sh [new file with mode: 0755]
upload-pack.c
index bd83683a87aa9797d4519bf7c20591df9d5c8de8..d6cd9a53552b1914de9077c8628f09fe892156de 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -722,6 +722,7 @@ TEST_BUILTINS_OBJS += test-mktemp.o
 TEST_BUILTINS_OBJS += test-online-cpus.o
 TEST_BUILTINS_OBJS += test-path-utils.o
 TEST_BUILTINS_OBJS += test-prio-queue.o
+TEST_BUILTINS_OBJS += test-reach.o
 TEST_BUILTINS_OBJS += test-read-cache.o
 TEST_BUILTINS_OBJS += test-read-midx.o
 TEST_BUILTINS_OBJS += test-ref-store.o
@@ -836,6 +837,7 @@ LIB_OBJS += column.o
 LIB_OBJS += combine-diff.o
 LIB_OBJS += commit.o
 LIB_OBJS += commit-graph.o
+LIB_OBJS += commit-reach.o
 LIB_OBJS += compat/obstack.o
 LIB_OBJS += compat/terminal.o
 LIB_OBJS += config.o
index e1275ba79e8e7368f5448043e321db2b9376aa71..d023543c911d040b651f343a05b818b053def808 100644 (file)
--- a/bisect.c
+++ b/bisect.c
@@ -13,6 +13,7 @@
 #include "sha1-array.h"
 #include "argv-array.h"
 #include "commit-slab.h"
+#include "commit-reach.h"
 
 static struct oid_array good_revs;
 static struct oid_array skipped_revs;
index 5b4d883e1f6f432ce07aed6ac86532c6d877a969..c396c41533c38630378db370f1db30e99aad849b 100644 (file)
@@ -23,6 +23,7 @@
 #include "ref-filter.h"
 #include "worktree.h"
 #include "help.h"
+#include "commit-reach.h"
 
 static const char * const builtin_branch_usage[] = {
        N_("git branch [<options>] [-r | -a] [--merged | --no-merged]"),
index 0d9828e29ebe89f037e68761d5cd5b407339cd48..fa3e53232d2d24564a2de6370b3bdef72a153735 100644 (file)
@@ -33,6 +33,7 @@
 #include "sequencer.h"
 #include "mailmap.h"
 #include "help.h"
+#include "commit-reach.h"
 
 static const char * const builtin_commit_usage[] = {
        N_("git commit [<options>] [--] <pathspec>..."),
index 61bec5d213d47141d14162bd1a2ca88861c22ef7..eed15c78137a7e86be3ad7600b0001e33b1f7aa7 100644 (file)
@@ -22,6 +22,7 @@
 #include "utf8.h"
 #include "packfile.h"
 #include "list-objects-filter-options.h"
+#include "commit-reach.h"
 
 static const char * const builtin_fetch_usage[] = {
        N_("git fetch [<options>] [<repository> [<refspec>...]]"),
index f35ff1612bb563c819b611e82f8e3a7730d32461..e5668f27d8df7deee8705587e3c9eddb0be61818 100644 (file)
@@ -12,6 +12,7 @@
 #include "fmt-merge-msg.h"
 #include "gpg-interface.h"
 #include "repository.h"
+#include "commit-reach.h"
 
 static const char * const fmt_merge_msg_usage[] = {
        N_("git fmt-merge-msg [-m <message>] [--log[=<n>] | --no-log] [--file <file>]"),
index e094560d9abca6e819c24b845dc7c04d384850c3..517c5e67890d421fd1f15fb454221eb1fa0634f4 100644 (file)
@@ -31,6 +31,7 @@
 #include "progress.h"
 #include "commit-slab.h"
 #include "repository.h"
+#include "commit-reach.h"
 
 #define MAIL_DEFAULT_WRAP 72
 
index 08d91b1f0c0172fef93f1a87bf0843a85f57ca37..1c920990701381452da910e4cee66be5e6fde5a0 100644 (file)
@@ -7,6 +7,7 @@
 #include "revision.h"
 #include "parse-options.h"
 #include "repository.h"
+#include "commit-reach.h"
 
 static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
 {
index 8f4a5065c209b5b50e02271b48277fff90306338..7a8e3e274f43c6b184defe24d9d4c09a76d63a3e 100644 (file)
@@ -36,6 +36,7 @@
 #include "packfile.h"
 #include "tag.h"
 #include "alias.h"
+#include "commit-reach.h"
 
 #define DEFAULT_TWOHEAD (1<<0)
 #define DEFAULT_OCTOPUS (1<<1)
index 681c127a07071c98641972227a28dbe7f77eaf70..2514bfb9cd6b4288bcda5e1676e3d4e20f10f281 100644 (file)
@@ -22,6 +22,7 @@
 #include "tempfile.h"
 #include "lockfile.h"
 #include "wt-status.h"
+#include "commit-reach.h"
 
 enum rebase_type {
        REBASE_INVALID = -1,
index c17ce94e12ee34c5b822b0e09fcd6d7264e759ad..35a3fcfbd96bbc18a777be5a70e21edb35decffb 100644 (file)
@@ -27,6 +27,7 @@
 #include "packfile.h"
 #include "object-store.h"
 #include "protocol.h"
+#include "commit-reach.h"
 
 static const char * const receive_pack_usage[] = {
        N_("git receive-pack <git-dir>"),
index 7876db1c20d317e28e4a84880197c6a690bf9ef6..61479bc428c80ef0b976cd46aa8cb60c1d1550f8 100644 (file)
@@ -10,6 +10,7 @@
 #include "refspec.h"
 #include "object-store.h"
 #include "argv-array.h"
+#include "commit-reach.h"
 
 static const char * const builtin_remote_usage[] = {
        N_("git remote [-v | --verbose]"),
index 0f09bbbf65a4bc8d6d064a985181ac547d9ee411..455f62246d69ad0468ffde58e568732bd3339c63 100644 (file)
@@ -14,6 +14,7 @@
 #include "revision.h"
 #include "split-index.h"
 #include "submodule.h"
+#include "commit-reach.h"
 
 #define DO_REVS                1
 #define DO_NOREV       2
index 8a1bec7b8aa420dd3d4ecadc95dee31029533c07..0cad55eec2d5603ccd375e093206f0c971c3524a 100644 (file)
@@ -233,6 +233,24 @@ static int prepare_commit_graph(struct repository *r)
        return !!r->objects->commit_graph;
 }
 
+int generation_numbers_enabled(struct repository *r)
+{
+       uint32_t first_generation;
+       struct commit_graph *g;
+       if (!prepare_commit_graph(r))
+              return 0;
+
+       g = r->objects->commit_graph;
+
+       if (!g->num_commits)
+               return 0;
+
+       first_generation = get_be32(g->chunk_commit_data +
+                                   g->hash_len + 8) >> 2;
+
+       return !!first_generation;
+}
+
 static void close_commit_graph(void)
 {
        free_commit_graph(the_repository->objects->commit_graph);
index eea62f8c0ee53b56630a1a2b0c2c716b4cd63670..698f09e2bc876cf9ccfed04022827dc1fdd9bfbd 100644 (file)
@@ -52,6 +52,12 @@ struct commit_graph {
 
 struct commit_graph *load_commit_graph_one(const char *graph_file);
 
+/*
+ * Return 1 if and only if the repository has a commit-graph
+ * file and generation numbers are computed in that file.
+ */
+int generation_numbers_enabled(struct repository *r);
+
 void write_commit_graph_reachable(const char *obj_dir, int append);
 void write_commit_graph(const char *obj_dir,
                        struct string_list *pack_indexes,
diff --git a/commit-reach.c b/commit-reach.c
new file mode 100644 (file)
index 0000000..622eeb3
--- /dev/null
@@ -0,0 +1,665 @@
+#include "cache.h"
+#include "commit.h"
+#include "commit-graph.h"
+#include "decorate.h"
+#include "prio-queue.h"
+#include "tree.h"
+#include "ref-filter.h"
+#include "revision.h"
+#include "tag.h"
+#include "commit-reach.h"
+
+/* Remember to update object flag allocation in object.h */
+#define REACHABLE       (1u<<15)
+#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;
+
+       if (generation_numbers_enabled(the_repository)) {
+               struct commit_list *from_list = NULL;
+               int result;
+               commit_list_insert(commit, &from_list);
+               result = can_all_from_reach(from_list, with_commit, 0);
+               free_commit_list(from_list);
+               return result;
+       } else {
+               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;
+}
+
+int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid)
+{
+       struct object *o;
+       struct commit *old_commit, *new_commit;
+       struct commit_list *old_commit_list = NULL;
+
+       /*
+        * Both new_commit and old_commit must be commit-ish and new_commit is descendant of
+        * old_commit.  Otherwise we require --force.
+        */
+       o = deref_tag(the_repository, parse_object(the_repository, old_oid),
+                     NULL, 0);
+       if (!o || o->type != OBJ_COMMIT)
+               return 0;
+       old_commit = (struct commit *) o;
+
+       o = deref_tag(the_repository, parse_object(the_repository, new_oid),
+                     NULL, 0);
+       if (!o || o->type != OBJ_COMMIT)
+               return 0;
+       new_commit = (struct commit *) o;
+
+       if (parse_commit(new_commit) < 0)
+               return 0;
+
+       commit_list_insert(old_commit, &old_commit_list);
+       return is_descendant_of(new_commit, old_commit_list);
+}
+
+/*
+ * Mimicking the real stack, this stack lives on the heap, avoiding stack
+ * overflows.
+ *
+ * At each recursion step, the stack items points to the commits whose
+ * ancestors are to be inspected.
+ */
+struct contains_stack {
+       int nr, alloc;
+       struct contains_stack_entry {
+               struct commit *commit;
+               struct commit_list *parents;
+       } *contains_stack;
+};
+
+static int in_commit_list(const struct commit_list *want, struct commit *c)
+{
+       for (; want; want = want->next)
+               if (!oidcmp(&want->item->object.oid, &c->object.oid))
+                       return 1;
+       return 0;
+}
+
+/*
+ * Test whether the candidate is contained in the list.
+ * Do not recurse to find out, though, but return -1 if inconclusive.
+ */
+static enum contains_result contains_test(struct commit *candidate,
+                                         const struct commit_list *want,
+                                         struct contains_cache *cache,
+                                         uint32_t cutoff)
+{
+       enum contains_result *cached = contains_cache_at(cache, candidate);
+
+       /* If we already have the answer cached, return that. */
+       if (*cached)
+               return *cached;
+
+       /* or are we it? */
+       if (in_commit_list(want, candidate)) {
+               *cached = CONTAINS_YES;
+               return CONTAINS_YES;
+       }
+
+       /* Otherwise, we don't know; prepare to recurse */
+       parse_commit_or_die(candidate);
+
+       if (candidate->generation < cutoff)
+               return CONTAINS_NO;
+
+       return CONTAINS_UNKNOWN;
+}
+
+static void push_to_contains_stack(struct commit *candidate, struct contains_stack *contains_stack)
+{
+       ALLOC_GROW(contains_stack->contains_stack, contains_stack->nr + 1, contains_stack->alloc);
+       contains_stack->contains_stack[contains_stack->nr].commit = candidate;
+       contains_stack->contains_stack[contains_stack->nr++].parents = candidate->parents;
+}
+
+static enum contains_result contains_tag_algo(struct commit *candidate,
+                                             const struct commit_list *want,
+                                             struct contains_cache *cache)
+{
+       struct contains_stack contains_stack = { 0, 0, NULL };
+       enum contains_result result;
+       uint32_t cutoff = GENERATION_NUMBER_INFINITY;
+       const struct commit_list *p;
+
+       for (p = want; p; p = p->next) {
+               struct commit *c = p->item;
+               load_commit_graph_info(the_repository, c);
+               if (c->generation < cutoff)
+                       cutoff = c->generation;
+       }
+
+       result = contains_test(candidate, want, cache, cutoff);
+       if (result != CONTAINS_UNKNOWN)
+               return result;
+
+       push_to_contains_stack(candidate, &contains_stack);
+       while (contains_stack.nr) {
+               struct contains_stack_entry *entry = &contains_stack.contains_stack[contains_stack.nr - 1];
+               struct commit *commit = entry->commit;
+               struct commit_list *parents = entry->parents;
+
+               if (!parents) {
+                       *contains_cache_at(cache, commit) = CONTAINS_NO;
+                       contains_stack.nr--;
+               }
+               /*
+                * If we just popped the stack, parents->item has been marked,
+                * therefore contains_test will return a meaningful yes/no.
+                */
+               else switch (contains_test(parents->item, want, cache, cutoff)) {
+               case CONTAINS_YES:
+                       *contains_cache_at(cache, commit) = CONTAINS_YES;
+                       contains_stack.nr--;
+                       break;
+               case CONTAINS_NO:
+                       entry->parents = parents->next;
+                       break;
+               case CONTAINS_UNKNOWN:
+                       push_to_contains_stack(parents->item, &contains_stack);
+                       break;
+               }
+       }
+       free(contains_stack.contains_stack);
+       return contains_test(candidate, want, cache, cutoff);
+}
+
+int commit_contains(struct ref_filter *filter, struct commit *commit,
+                   struct commit_list *list, struct contains_cache *cache)
+{
+       if (filter->with_commit_tag_algo)
+               return contains_tag_algo(commit, list, cache) == CONTAINS_YES;
+       return is_descendant_of(commit, list);
+}
+
+static int compare_commits_by_gen(const void *_a, const void *_b)
+{
+       const struct commit *a = (const struct commit *)_a;
+       const struct commit *b = (const struct commit *)_b;
+
+       if (a->generation < b->generation)
+               return -1;
+       if (a->generation > b->generation)
+               return 1;
+       return 0;
+}
+
+int can_all_from_reach_with_flag(struct object_array *from,
+                                unsigned int with_flag,
+                                unsigned int assign_flag,
+                                time_t min_commit_date,
+                                uint32_t min_generation)
+{
+       struct commit **list = NULL;
+       int i;
+       int result = 1;
+
+       ALLOC_ARRAY(list, from->nr);
+       for (i = 0; i < from->nr; i++) {
+               list[i] = (struct commit *)from->objects[i].item;
+
+               if (parse_commit(list[i]) ||
+                   list[i]->generation < min_generation)
+                       return 0;
+       }
+
+       QSORT(list, from->nr, compare_commits_by_gen);
+
+       for (i = 0; i < from->nr; i++) {
+               /* DFS from list[i] */
+               struct commit_list *stack = NULL;
+
+               list[i]->object.flags |= assign_flag;
+               commit_list_insert(list[i], &stack);
+
+               while (stack) {
+                       struct commit_list *parent;
+
+                       if (stack->item->object.flags & with_flag) {
+                               pop_commit(&stack);
+                               continue;
+                       }
+
+                       for (parent = stack->item->parents; parent; parent = parent->next) {
+                               if (parent->item->object.flags & (with_flag | RESULT))
+                                       stack->item->object.flags |= RESULT;
+
+                               if (!(parent->item->object.flags & assign_flag)) {
+                                       parent->item->object.flags |= assign_flag;
+
+                                       if (parse_commit(parent->item) ||
+                                           parent->item->date < min_commit_date ||
+                                           parent->item->generation < min_generation)
+                                               continue;
+
+                                       commit_list_insert(parent->item, &stack);
+                                       break;
+                               }
+                       }
+
+                       if (!parent)
+                               pop_commit(&stack);
+               }
+
+               if (!(list[i]->object.flags & (with_flag | RESULT))) {
+                       result = 0;
+                       goto cleanup;
+               }
+       }
+
+cleanup:
+       for (i = 0; i < from->nr; i++) {
+               clear_commit_marks(list[i], RESULT);
+               clear_commit_marks(list[i], assign_flag);
+       }
+       return result;
+}
+
+int can_all_from_reach(struct commit_list *from, struct commit_list *to,
+                      int cutoff_by_min_date)
+{
+       struct object_array from_objs = OBJECT_ARRAY_INIT;
+       time_t min_commit_date = cutoff_by_min_date ? from->item->date : 0;
+       struct commit_list *from_iter = from, *to_iter = to;
+       int result;
+       uint32_t min_generation = GENERATION_NUMBER_INFINITY;
+
+       while (from_iter) {
+               add_object_array(&from_iter->item->object, NULL, &from_objs);
+
+               if (!parse_commit(from_iter->item)) {
+                       if (from_iter->item->date < min_commit_date)
+                               min_commit_date = from_iter->item->date;
+
+                       if (from_iter->item->generation < min_generation)
+                               min_generation = from_iter->item->generation;
+               }
+
+               from_iter = from_iter->next;
+       }
+
+       while (to_iter) {
+               if (!parse_commit(to_iter->item)) {
+                       if (to_iter->item->date < min_commit_date)
+                               min_commit_date = to_iter->item->date;
+
+                       if (to_iter->item->generation < min_generation)
+                               min_generation = to_iter->item->generation;
+               }
+
+               to_iter->item->object.flags |= PARENT2;
+
+               to_iter = to_iter->next;
+       }
+
+       result = can_all_from_reach_with_flag(&from_objs, PARENT2, PARENT1,
+                                             min_commit_date, min_generation);
+
+       while (from) {
+               clear_commit_marks(from->item, PARENT1);
+               from = from->next;
+       }
+
+       while (to) {
+               clear_commit_marks(to->item, PARENT2);
+               to = to->next;
+       }
+
+       object_array_clear(&from_objs);
+       return result;
+}
diff --git a/commit-reach.h b/commit-reach.h
new file mode 100644 (file)
index 0000000..7d313e2
--- /dev/null
@@ -0,0 +1,77 @@
+#ifndef __COMMIT_REACH_H__
+#define __COMMIT_REACH_H__
+
+#include "commit-slab.h"
+
+struct commit;
+struct commit_list;
+struct contains_cache;
+struct ref_filter;
+
+struct commit_list *get_merge_bases_many(struct commit *one,
+                                        int n,
+                                        struct commit **twos);
+struct commit_list *get_merge_bases_many_dirty(struct commit *one,
+                                              int n,
+                                              struct commit **twos);
+struct commit_list *get_merge_bases(struct commit *one, struct commit *two);
+struct commit_list *get_octopus_merge_bases(struct commit_list *in);
+
+/* To be used only when object flags after this call no longer matter */
+struct commit_list *get_merge_bases_many_dirty(struct commit *one, int n, struct commit **twos);
+
+int is_descendant_of(struct commit *commit, struct commit_list *with_commit);
+int in_merge_bases_many(struct commit *commit, int nr_reference, struct commit **reference);
+int in_merge_bases(struct commit *commit, struct commit *reference);
+
+/*
+ * Takes a list of commits and returns a new list where those
+ * have been removed that can be reached from other commits in
+ * the list. It is useful for, e.g., reducing the commits
+ * randomly thrown at the git-merge command and removing
+ * redundant commits that the user shouldn't have given to it.
+ *
+ * This function destroys the STALE bit of the commit objects'
+ * flags.
+ */
+struct commit_list *reduce_heads(struct commit_list *heads);
+
+/*
+ * Like `reduce_heads()`, except it replaces the list. Use this
+ * instead of `foo = reduce_heads(foo);` to avoid memory leaks.
+ */
+void reduce_heads_replace(struct commit_list **heads);
+
+int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid);
+
+/*
+ * Unknown has to be "0" here, because that's the default value for
+ * contains_cache slab entries that have not yet been assigned.
+ */
+enum contains_result {
+       CONTAINS_UNKNOWN = 0,
+       CONTAINS_NO,
+       CONTAINS_YES
+};
+
+define_commit_slab(contains_cache, enum contains_result);
+
+int commit_contains(struct ref_filter *filter, struct commit *commit,
+                   struct commit_list *list, struct contains_cache *cache);
+
+/*
+ * Determine if every commit in 'from' can reach at least one commit
+ * that is marked with 'with_flag'. As we traverse, use 'assign_flag'
+ * as a marker for commits that are already visited. Do not walk
+ * commits with date below 'min_commit_date' or generation below
+ * 'min_generation'.
+ */
+int can_all_from_reach_with_flag(struct object_array *from,
+                                unsigned int with_flag,
+                                unsigned int assign_flag,
+                                time_t min_commit_date,
+                                uint32_t min_generation);
+int can_all_from_reach(struct commit_list *from, struct commit_list *to,
+                      int commit_date_cutoff);
+
+#endif
index 449c1f4920cff631f5cf2479772c350c9b8b7325..5781f9bc675722041b9ffb0471f4c959fba48924 100644 (file)
--- a/commit.c
+++ b/commit.c
@@ -843,367 +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;
 
index da0db36eba2bf16277dbb7aadcb3384e29191ecc..e2c99d9b04f6b2b841c94524e4c56c34d89b282c 100644 (file)
--- a/commit.h
+++ b/commit.h
@@ -204,13 +204,6 @@ struct commit_graft *read_graft_line(struct strbuf *line);
 int register_commit_graft(struct repository *r, struct commit_graft *, int);
 struct commit_graft *lookup_commit_graft(struct repository *r, const struct object_id *oid);
 
-extern struct commit_list *get_merge_bases(struct commit *rev1, struct commit *rev2);
-extern struct commit_list *get_merge_bases_many(struct commit *one, int n, struct commit **twos);
-extern struct commit_list *get_octopus_merge_bases(struct commit_list *in);
-
-/* To be used only when object flags after this call no longer matter */
-extern struct commit_list *get_merge_bases_many_dirty(struct commit *one, int n, struct commit **twos);
-
 /* largest positive number a signed 32-bit integer can contain */
 #define INFINITE_DEPTH 0x7fffffff
 
@@ -258,32 +251,10 @@ extern int delayed_reachability_test(struct shallow_info *si, int c);
 extern void prune_shallow(int show_only);
 extern struct trace_key trace_shallow;
 
-int is_descendant_of(struct commit *, struct commit_list *);
-int in_merge_bases(struct commit *, struct commit *);
-int in_merge_bases_many(struct commit *, int, struct commit **);
-
 extern int interactive_add(int argc, const char **argv, const char *prefix, int patch);
 extern int run_add_interactive(const char *revision, const char *patch_mode,
                               const struct pathspec *pathspec);
 
-/*
- * Takes a list of commits and returns a new list where those
- * have been removed that can be reached from other commits in
- * the list. It is useful for, e.g., reducing the commits
- * randomly thrown at the git-merge command and removing
- * redundant commits that the user shouldn't have given to it.
- *
- * This function destroys the STALE bit of the commit objects'
- * flags.
- */
-extern struct commit_list *reduce_heads(struct commit_list *heads);
-
-/*
- * Like `reduce_heads()`, except it replaces the list. Use this
- * instead of `foo = reduce_heads(foo);` to avoid memory leaks.
- */
-extern void reduce_heads_replace(struct commit_list **heads);
-
 struct commit_extra_header {
        struct commit_extra_header *next;
        char *key;
index f8c3acd3b5577caa24c13402ea2b6f733e41aec5..af6514fdea9959b26355b328221ceb67eaf1432f 100644 (file)
@@ -171,6 +171,7 @@ Format of STDIN stream:
 #include "packfile.h"
 #include "object-store.h"
 #include "mem-pool.h"
+#include "commit-reach.h"
 
 #define PACK_ID_BITS 16
 #define MAX_PACK_ID ((1<<PACK_ID_BITS)-1)
index 5eaf551b51e7aaf87219d4af0ca19873484c90ca..91fdc7e1d5d987203d9df3a6c6a86b917f27b939 100644 (file)
@@ -14,7 +14,7 @@
 #include "argv-array.h"
 #include "packfile.h"
 #include "object-store.h"
-
+#include "commit-reach.h"
 
 #ifdef EXPAT_NEEDS_XMLPARSE_H
 #include <xmlparse.h>
index e5243dbc542d786a645a9c038c855a6ca30acaba..d9d78ec3832c54cae373e9fb688d5153e66830e2 100644 (file)
@@ -27,6 +27,7 @@
 #include "dir.h"
 #include "submodule.h"
 #include "revision.h"
+#include "commit-reach.h"
 
 struct path_hashmap_entry {
        struct hashmap_entry e;
index 76ab19e702423aeb511bfc1e939a7998c61fab61..12dfdf6c17015442d51577a0b621ec20d344ca20 100644 (file)
@@ -12,6 +12,7 @@
 #include "notes-merge.h"
 #include "strbuf.h"
 #include "notes-utils.h"
+#include "commit-reach.h"
 
 struct notes_merge_pair {
        struct object_id obj, base, local, remote;
index 6e28fdd0b426a3e276001e674675cf386f7d86c1..0feb90ae613be04d56ac091307c9b2be88724e42 100644 (file)
--- a/object.h
+++ b/object.h
@@ -63,12 +63,12 @@ struct object_array {
  * fetch-pack.c:             01
  * negotiator/default.c:       2--5
  * walker.c:                 0-2
- * upload-pack.c:                4       11----------------19
+ * upload-pack.c:                4       11-----14  16-----19
  * builtin/blame.c:                        12-13
  * bisect.c:                                        16
  * bundle.c:                                        16
  * http-push.c:                                     16-----19
- * commit.c:                                        16-----19
+ * commit-reach.c:                                15-------19
  * sha1-name.c:                                              20
  * list-objects-filter.c:                                      21
  * builtin/fsck.c:           0--3
index d977e9bacb19ed766dd0a501b6fbcae800bb4ae0..fc82f37a02772244ee93aee41bef9238075c07ba 100644 (file)
@@ -11,6 +11,7 @@
 #include "pack-bitmap.h"
 #include "sha1-lookup.h"
 #include "pack-objects.h"
+#include "commit-reach.h"
 
 struct bitmapped_commit {
        struct commit *commit;
index 0bccfceff2ae31200019838d9f2b67e13e32ef6f..9bacd32f0a0a72854c81d0d114520efb554c04a8 100644 (file)
@@ -19,6 +19,7 @@
 #include "wt-status.h"
 #include "commit-slab.h"
 #include "commit-graph.h"
+#include "commit-reach.h"
 
 static struct ref_msg {
        const char *gone;
@@ -1673,144 +1674,6 @@ static int get_ref_atom_value(struct ref_array_item *ref, int atom,
        return 0;
 }
 
-/*
- * Unknown has to be "0" here, because that's the default value for
- * contains_cache slab entries that have not yet been assigned.
- */
-enum contains_result {
-       CONTAINS_UNKNOWN = 0,
-       CONTAINS_NO,
-       CONTAINS_YES
-};
-
-define_commit_slab(contains_cache, enum contains_result);
-
-struct ref_filter_cbdata {
-       struct ref_array *array;
-       struct ref_filter *filter;
-       struct contains_cache contains_cache;
-       struct contains_cache no_contains_cache;
-};
-
-/*
- * Mimicking the real stack, this stack lives on the heap, avoiding stack
- * overflows.
- *
- * At each recursion step, the stack items points to the commits whose
- * ancestors are to be inspected.
- */
-struct contains_stack {
-       int nr, alloc;
-       struct contains_stack_entry {
-               struct commit *commit;
-               struct commit_list *parents;
-       } *contains_stack;
-};
-
-static int in_commit_list(const struct commit_list *want, struct commit *c)
-{
-       for (; want; want = want->next)
-               if (!oidcmp(&want->item->object.oid, &c->object.oid))
-                       return 1;
-       return 0;
-}
-
-/*
- * Test whether the candidate is contained in the list.
- * Do not recurse to find out, though, but return -1 if inconclusive.
- */
-static enum contains_result contains_test(struct commit *candidate,
-                                         const struct commit_list *want,
-                                         struct contains_cache *cache,
-                                         uint32_t cutoff)
-{
-       enum contains_result *cached = contains_cache_at(cache, candidate);
-
-       /* If we already have the answer cached, return that. */
-       if (*cached)
-               return *cached;
-
-       /* or are we it? */
-       if (in_commit_list(want, candidate)) {
-               *cached = CONTAINS_YES;
-               return CONTAINS_YES;
-       }
-
-       /* Otherwise, we don't know; prepare to recurse */
-       parse_commit_or_die(candidate);
-
-       if (candidate->generation < cutoff)
-               return CONTAINS_NO;
-
-       return CONTAINS_UNKNOWN;
-}
-
-static void push_to_contains_stack(struct commit *candidate, struct contains_stack *contains_stack)
-{
-       ALLOC_GROW(contains_stack->contains_stack, contains_stack->nr + 1, contains_stack->alloc);
-       contains_stack->contains_stack[contains_stack->nr].commit = candidate;
-       contains_stack->contains_stack[contains_stack->nr++].parents = candidate->parents;
-}
-
-static enum contains_result contains_tag_algo(struct commit *candidate,
-                                             const struct commit_list *want,
-                                             struct contains_cache *cache)
-{
-       struct contains_stack contains_stack = { 0, 0, NULL };
-       enum contains_result result;
-       uint32_t cutoff = GENERATION_NUMBER_INFINITY;
-       const struct commit_list *p;
-
-       for (p = want; p; p = p->next) {
-               struct commit *c = p->item;
-               load_commit_graph_info(the_repository, c);
-               if (c->generation < cutoff)
-                       cutoff = c->generation;
-       }
-
-       result = contains_test(candidate, want, cache, cutoff);
-       if (result != CONTAINS_UNKNOWN)
-               return result;
-
-       push_to_contains_stack(candidate, &contains_stack);
-       while (contains_stack.nr) {
-               struct contains_stack_entry *entry = &contains_stack.contains_stack[contains_stack.nr - 1];
-               struct commit *commit = entry->commit;
-               struct commit_list *parents = entry->parents;
-
-               if (!parents) {
-                       *contains_cache_at(cache, commit) = CONTAINS_NO;
-                       contains_stack.nr--;
-               }
-               /*
-                * If we just popped the stack, parents->item has been marked,
-                * therefore contains_test will return a meaningful yes/no.
-                */
-               else switch (contains_test(parents->item, want, cache, cutoff)) {
-               case CONTAINS_YES:
-                       *contains_cache_at(cache, commit) = CONTAINS_YES;
-                       contains_stack.nr--;
-                       break;
-               case CONTAINS_NO:
-                       entry->parents = parents->next;
-                       break;
-               case CONTAINS_UNKNOWN:
-                       push_to_contains_stack(parents->item, &contains_stack);
-                       break;
-               }
-       }
-       free(contains_stack.contains_stack);
-       return contains_test(candidate, want, cache, cutoff);
-}
-
-static int commit_contains(struct ref_filter *filter, struct commit *commit,
-                          struct commit_list *list, struct contains_cache *cache)
-{
-       if (filter->with_commit_tag_algo)
-               return contains_tag_algo(commit, list, cache) == CONTAINS_YES;
-       return is_descendant_of(commit, list);
-}
-
 /*
  * Return 1 if the refname matches one of the patterns, otherwise 0.
  * A pattern can be a literal prefix (e.g. a refname "refs/heads/master"
@@ -2046,6 +1909,13 @@ static int filter_ref_kind(struct ref_filter *filter, const char *refname)
        return ref_kind_from_refname(refname);
 }
 
+struct ref_filter_cbdata {
+       struct ref_array *array;
+       struct ref_filter *filter;
+       struct contains_cache contains_cache;
+       struct contains_cache no_contains_cache;
+};
+
 /*
  * A call-back given to for_each_ref().  Filter refs and keep them for
  * later object processing.
index 7f6277a1451d147fc5af4ae2910e7c40dd330aec..9a079517691331fae9cfc46d796c2d296081a7cc 100644 (file)
--- a/remote.c
+++ b/remote.c
@@ -12,6 +12,7 @@
 #include "string-list.h"
 #include "mergesort.h"
 #include "argv-array.h"
+#include "commit-reach.h"
 
 enum map_direction { FROM_SRC, FROM_DST };
 
@@ -1791,55 +1792,6 @@ int resolve_remote_symref(struct ref *ref, struct ref *list)
        return 1;
 }
 
-static void unmark_and_free(struct commit_list *list, unsigned int mark)
-{
-       while (list) {
-               struct commit *commit = pop_commit(&list);
-               commit->object.flags &= ~mark;
-       }
-}
-
-int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid)
-{
-       struct object *o;
-       struct commit *old_commit, *new_commit;
-       struct commit_list *list, *used;
-       int found = 0;
-
-       /*
-        * Both new_commit and old_commit must be commit-ish and new_commit is descendant of
-        * old_commit.  Otherwise we require --force.
-        */
-       o = deref_tag(the_repository, parse_object(the_repository, old_oid),
-                     NULL, 0);
-       if (!o || o->type != OBJ_COMMIT)
-               return 0;
-       old_commit = (struct commit *) o;
-
-       o = deref_tag(the_repository, parse_object(the_repository, new_oid),
-                     NULL, 0);
-       if (!o || o->type != OBJ_COMMIT)
-               return 0;
-       new_commit = (struct commit *) o;
-
-       if (parse_commit(new_commit) < 0)
-               return 0;
-
-       used = list = NULL;
-       commit_list_insert(new_commit, &list);
-       while (list) {
-               new_commit = pop_most_recent_commit(&list, TMP_MARK);
-               commit_list_insert(new_commit, &used);
-               if (new_commit == old_commit) {
-                       found = 1;
-                       break;
-               }
-       }
-       unmark_and_free(list, TMP_MARK);
-       unmark_and_free(used, TMP_MARK);
-       return found;
-}
-
 /*
  * Lookup the upstream branch for the given branch and if present, optionally
  * compute the commit ahead/behind values for the pair.
index 88f8480c71a2e5ac494ef65532619a4322c1d32a..da53ad570b91dbd4a820ffc79541fb0a4915ff6b 100644 (file)
--- a/remote.h
+++ b/remote.h
@@ -151,7 +151,6 @@ extern struct ref **get_remote_refs(int fd_out, struct packet_reader *reader,
                                    const struct string_list *server_options);
 
 int resolve_remote_symref(struct ref *ref, struct ref *list);
-int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid);
 
 /*
  * Remove and free all but the first of any entries in the input list
index 46228f82ee50166fb135d457f808b52629f48394..494cc041faba7921781cfa7b35c3bd56e877ec6f 100644 (file)
@@ -24,6 +24,7 @@
 #include "packfile.h"
 #include "worktree.h"
 #include "argv-array.h"
+#include "commit-reach.h"
 
 volatile show_early_output_fn_t show_early_output;
 
index dc2c58d464c14be033f4bcba2ab4332886ead327..bd159991e9ca1ad85fe831d84031f6d889e3c090 100644 (file)
@@ -30,6 +30,7 @@
 #include "oidset.h"
 #include "commit-slab.h"
 #include "alias.h"
+#include "commit-reach.h"
 
 #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
 
index 6cccfbbfbff396fb17ac9f3f357dcead802ecf94..fbcd2f78eb3fafc84748063d46e14f5153ffe4bc 100644 (file)
@@ -13,6 +13,7 @@
 #include "object-store.h"
 #include "repository.h"
 #include "midx.h"
+#include "commit-reach.h"
 
 static int get_oid_oneline(const char *, struct object_id *, struct commit_list *);
 
index dbe8a2a2906abf9b393eeca1cdad8c9425c3e4bb..99fd2d1ba0f70aaf238f55aae006a12e38090342 100644 (file)
--- a/shallow.c
+++ b/shallow.c
@@ -16,6 +16,7 @@
 #include "list-objects.h"
 #include "commit-slab.h"
 #include "repository.h"
+#include "commit-reach.h"
 
 void set_alternate_shallow_file(struct repository *r, const char *path, int override)
 {
index a2b266fbfae2cd89b00a11008fbcd28bf09777e2..058fc9f8855d7719cbc9bb17d646b63d99772c87 100644 (file)
@@ -22,6 +22,7 @@
 #include "worktree.h"
 #include "parse-options.h"
 #include "object-store.h"
+#include "commit-reach.h"
 
 static int config_update_recurse_submodules = RECURSE_SUBMODULES_OFF;
 static struct string_list changed_submodule_names = STRING_LIST_INIT_DUP;
diff --git a/t/helper/test-reach.c b/t/helper/test-reach.c
new file mode 100644 (file)
index 0000000..eb21103
--- /dev/null
@@ -0,0 +1,130 @@
+#include "test-tool.h"
+#include "cache.h"
+#include "commit.h"
+#include "commit-reach.h"
+#include "config.h"
+#include "parse-options.h"
+#include "ref-filter.h"
+#include "string-list.h"
+#include "tag.h"
+
+static void print_sorted_commit_ids(struct commit_list *list)
+{
+       int i;
+       struct string_list s = STRING_LIST_INIT_DUP;
+
+       while (list) {
+               string_list_append(&s, oid_to_hex(&list->item->object.oid));
+               list = list->next;
+       }
+
+       string_list_sort(&s);
+
+       for (i = 0; i < s.nr; i++)
+               printf("%s\n", s.items[i].string);
+
+       string_list_clear(&s, 0);
+}
+
+int cmd__reach(int ac, const char **av)
+{
+       struct object_id oid_A, oid_B;
+       struct commit *A, *B;
+       struct commit_list *X, *Y;
+       struct commit **X_array;
+       int X_nr, X_alloc;
+       struct strbuf buf = STRBUF_INIT;
+       struct repository *r = the_repository;
+
+       setup_git_directory();
+
+       if (ac < 2)
+               exit(1);
+
+       A = B = NULL;
+       X = Y = NULL;
+       X_nr = 0;
+       X_alloc = 16;
+       ALLOC_ARRAY(X_array, X_alloc);
+
+       while (strbuf_getline(&buf, stdin) != EOF) {
+               struct object_id oid;
+               struct object *o;
+               struct commit *c;
+               if (buf.len < 3)
+                       continue;
+
+               if (get_oid_committish(buf.buf + 2, &oid))
+                       die("failed to resolve %s", buf.buf + 2);
+
+               o = parse_object(r, &oid);
+               o = deref_tag_noverify(o);
+
+               if (!o)
+                       die("failed to load commit for input %s resulting in oid %s\n",
+                           buf.buf, oid_to_hex(&oid));
+
+               c = object_as_type(r, o, OBJ_COMMIT, 0);
+
+               if (!c)
+                       die("failed to load commit for input %s resulting in oid %s\n",
+                           buf.buf, oid_to_hex(&oid));
+
+               switch (buf.buf[0]) {
+                       case 'A':
+                               oidcpy(&oid_A, &oid);
+                               A = c;
+                               break;
+
+                       case 'B':
+                               oidcpy(&oid_B, &oid);
+                               B = c;
+                               break;
+
+                       case 'X':
+                               commit_list_insert(c, &X);
+                               ALLOC_GROW(X_array, X_nr + 1, X_alloc);
+                               X_array[X_nr++] = c;
+                               break;
+
+                       case 'Y':
+                               commit_list_insert(c, &Y);
+                               break;
+
+                       default:
+                               die("unexpected start of line: %c", buf.buf[0]);
+               }
+       }
+       strbuf_release(&buf);
+
+       if (!strcmp(av[1], "ref_newer"))
+               printf("%s(A,B):%d\n", av[1], ref_newer(&oid_A, &oid_B));
+       else if (!strcmp(av[1], "in_merge_bases"))
+               printf("%s(A,B):%d\n", av[1], in_merge_bases(A, B));
+       else if (!strcmp(av[1], "is_descendant_of"))
+               printf("%s(A,X):%d\n", av[1], is_descendant_of(A, X));
+       else if (!strcmp(av[1], "get_merge_bases_many")) {
+               struct commit_list *list = get_merge_bases_many(A, X_nr, X_array);
+               printf("%s(A,X):\n", av[1]);
+               print_sorted_commit_ids(list);
+       } else if (!strcmp(av[1], "reduce_heads")) {
+               struct commit_list *list = reduce_heads(X);
+               printf("%s(X):\n", av[1]);
+               print_sorted_commit_ids(list);
+       } else if (!strcmp(av[1], "can_all_from_reach")) {
+               printf("%s(X,Y):%d\n", av[1], can_all_from_reach(X, Y, 1));
+       } else if (!strcmp(av[1], "commit_contains")) {
+               struct ref_filter filter;
+               struct contains_cache cache;
+               init_contains_cache(&cache);
+
+               if (ac > 2 && !strcmp(av[2], "--tag"))
+                       filter.with_commit_tag_algo = 1;
+               else
+                       filter.with_commit_tag_algo = 0;
+
+               printf("%s(_,A,X,_):%d\n", av[1], commit_contains(&filter, A, X, &cache));
+       }
+
+       exit(0);
+}
index 32767017102650db48115ffa69aea5c6b5636a4c..bef50c4dcc7c595c22074b3f5ceb62cf260a6393 100644 (file)
@@ -27,6 +27,7 @@ static struct test_cmd cmds[] = {
        { "online-cpus", cmd__online_cpus },
        { "path-utils", cmd__path_utils },
        { "prio-queue", cmd__prio_queue },
+       { "reach", cmd__reach },
        { "read-cache", cmd__read_cache },
        { "read-midx", cmd__read_midx },
        { "ref-store", cmd__ref_store },
index 710fb1b28625d26555f809844955b8785f5e2a4c..321982e4bc0366281af400f67ebd2ca3e68fffe7 100644 (file)
@@ -23,6 +23,7 @@ int cmd__mktemp(int argc, const char **argv);
 int cmd__online_cpus(int argc, const char **argv);
 int cmd__path_utils(int argc, const char **argv);
 int cmd__prio_queue(int argc, const char **argv);
+int cmd__reach(int argc, const char **argv);
 int cmd__read_cache(int argc, const char **argv);
 int cmd__read_midx(int argc, const char **argv);
 int cmd__ref_store(int argc, const char **argv);
diff --git a/t/t6600-test-reach.sh b/t/t6600-test-reach.sh
new file mode 100755 (executable)
index 0000000..d139a00
--- /dev/null
@@ -0,0 +1,242 @@
+#!/bin/sh
+
+test_description='basic commit reachability tests'
+
+. ./test-lib.sh
+
+# Construct a grid-like commit graph with points (x,y)
+# with 1 <= x <= 10, 1 <= y <= 10, where (x,y) has
+# parents (x-1, y) and (x, y-1), keeping in mind that
+# we drop a parent if a coordinate is nonpositive.
+#
+#             (10,10)
+#            /       \
+#         (10,9)    (9,10)
+#        /     \   /      \
+#    (10,8)    (9,9)      (8,10)
+#   /     \    /   \      /    \
+#         ( continued...)
+#   \     /    \   /      \    /
+#    (3,1)     (2,2)      (1,3)
+#        \     /    \     /
+#         (2,1)      (2,1)
+#              \    /
+#              (1,1)
+#
+# We use branch 'commit-x-y' to refer to (x,y).
+# This grid allows interesting reachability and
+# non-reachability queries: (x,y) can reach (x',y')
+# if and only if x' <= x and y' <= y.
+test_expect_success 'setup' '
+       for i in $(test_seq 1 10)
+       do
+               test_commit "1-$i" &&
+               git branch -f commit-1-$i
+       done &&
+       for j in $(test_seq 1 9)
+       do
+               git reset --hard commit-$j-1 &&
+               x=$(($j + 1)) &&
+               test_commit "$x-1" &&
+               git branch -f commit-$x-1 &&
+
+               for i in $(test_seq 2 10)
+               do
+                       git merge commit-$j-$i -m "$x-$i" &&
+                       git branch -f commit-$x-$i
+               done
+       done &&
+       git commit-graph write --reachable &&
+       mv .git/objects/info/commit-graph commit-graph-full &&
+       git show-ref -s commit-5-5 | git commit-graph write --stdin-commits &&
+       mv .git/objects/info/commit-graph commit-graph-half &&
+       git config core.commitGraph true
+'
+
+test_three_modes () {
+       test_when_finished rm -rf .git/objects/info/commit-graph &&
+       test-tool reach $1 <input >actual &&
+       test_cmp expect actual &&
+       cp commit-graph-full .git/objects/info/commit-graph &&
+       test-tool reach $1 <input >actual &&
+       test_cmp expect actual &&
+       cp commit-graph-half .git/objects/info/commit-graph &&
+       test-tool reach $1 <input >actual &&
+       test_cmp expect actual
+}
+
+test_expect_success 'ref_newer:miss' '
+       cat >input <<-\EOF &&
+       A:commit-5-7
+       B:commit-4-9
+       EOF
+       echo "ref_newer(A,B):0" >expect &&
+       test_three_modes ref_newer
+'
+
+test_expect_success 'ref_newer:hit' '
+       cat >input <<-\EOF &&
+       A:commit-5-7
+       B:commit-2-3
+       EOF
+       echo "ref_newer(A,B):1" >expect &&
+       test_three_modes ref_newer
+'
+
+test_expect_success 'in_merge_bases:hit' '
+       cat >input <<-\EOF &&
+       A:commit-5-7
+       B:commit-8-8
+       EOF
+       echo "in_merge_bases(A,B):1" >expect &&
+       test_three_modes in_merge_bases
+'
+
+test_expect_success 'in_merge_bases:miss' '
+       cat >input <<-\EOF &&
+       A:commit-6-8
+       B:commit-5-9
+       EOF
+       echo "in_merge_bases(A,B):0" >expect &&
+       test_three_modes in_merge_bases
+'
+
+test_expect_success 'is_descendant_of:hit' '
+       cat >input <<-\EOF &&
+       A:commit-5-7
+       X:commit-4-8
+       X:commit-6-6
+       X:commit-1-1
+       EOF
+       echo "is_descendant_of(A,X):1" >expect &&
+       test_three_modes is_descendant_of
+'
+
+test_expect_success 'is_descendant_of:miss' '
+       cat >input <<-\EOF &&
+       A:commit-6-8
+       X:commit-5-9
+       X:commit-4-10
+       X:commit-7-6
+       EOF
+       echo "is_descendant_of(A,X):0" >expect &&
+       test_three_modes is_descendant_of
+'
+
+test_expect_success 'get_merge_bases_many' '
+       cat >input <<-\EOF &&
+       A:commit-5-7
+       X:commit-4-8
+       X:commit-6-6
+       X:commit-8-3
+       EOF
+       {
+               echo "get_merge_bases_many(A,X):" &&
+               git rev-parse commit-5-6 \
+                             commit-4-7 | sort
+       } >expect &&
+       test_three_modes get_merge_bases_many
+'
+
+test_expect_success 'reduce_heads' '
+       cat >input <<-\EOF &&
+       X:commit-1-10
+       X:commit-2-8
+       X:commit-3-6
+       X:commit-4-4
+       X:commit-1-7
+       X:commit-2-5
+       X:commit-3-3
+       X:commit-5-1
+       EOF
+       {
+               echo "reduce_heads(X):" &&
+               git rev-parse commit-5-1 \
+                             commit-4-4 \
+                             commit-3-6 \
+                             commit-2-8 \
+                             commit-1-10 | sort
+       } >expect &&
+       test_three_modes reduce_heads
+'
+
+test_expect_success 'can_all_from_reach:hit' '
+       cat >input <<-\EOF &&
+       X:commit-2-10
+       X:commit-3-9
+       X:commit-4-8
+       X:commit-5-7
+       X:commit-6-6
+       X:commit-7-5
+       X:commit-8-4
+       X:commit-9-3
+       Y:commit-1-9
+       Y:commit-2-8
+       Y:commit-3-7
+       Y:commit-4-6
+       Y:commit-5-5
+       Y:commit-6-4
+       Y:commit-7-3
+       Y:commit-8-1
+       EOF
+       echo "can_all_from_reach(X,Y):1" >expect &&
+       test_three_modes can_all_from_reach
+'
+
+test_expect_success 'can_all_from_reach:miss' '
+       cat >input <<-\EOF &&
+       X:commit-2-10
+       X:commit-3-9
+       X:commit-4-8
+       X:commit-5-7
+       X:commit-6-6
+       X:commit-7-5
+       X:commit-8-4
+       X:commit-9-3
+       Y:commit-1-9
+       Y:commit-2-8
+       Y:commit-3-7
+       Y:commit-4-6
+       Y:commit-5-5
+       Y:commit-6-4
+       Y:commit-8-5
+       EOF
+       echo "can_all_from_reach(X,Y):0" >expect &&
+       test_three_modes can_all_from_reach
+'
+
+test_expect_success 'commit_contains:hit' '
+       cat >input <<-\EOF &&
+       A:commit-7-7
+       X:commit-2-10
+       X:commit-3-9
+       X:commit-4-8
+       X:commit-5-7
+       X:commit-6-6
+       X:commit-7-5
+       X:commit-8-4
+       X:commit-9-3
+       EOF
+       echo "commit_contains(_,A,X,_):1" >expect &&
+       test_three_modes commit_contains &&
+       test_three_modes commit_contains --tag
+'
+
+test_expect_success 'commit_contains:miss' '
+       cat >input <<-\EOF &&
+       A:commit-6-5
+       X:commit-2-10
+       X:commit-3-9
+       X:commit-4-8
+       X:commit-5-7
+       X:commit-6-6
+       X:commit-7-5
+       X:commit-8-4
+       X:commit-9-3
+       EOF
+       echo "commit_contains(_,A,X,_):0" >expect &&
+       test_three_modes commit_contains &&
+       test_three_modes commit_contains --tag
+'
+
+test_done
index 82b393ec31917c0c2bcd904668a60b5aaef00633..62a1000f4401f4314f072b61046d7a19d9d04bae 100644 (file)
 #include "quote.h"
 #include "upload-pack.h"
 #include "serve.h"
+#include "commit-reach.h"
 
 /* Remember to update object flag allocation in object.h */
 #define THEY_HAVE      (1u << 11)
 #define OUR_REF                (1u << 12)
 #define WANTED         (1u << 13)
 #define COMMON_KNOWN   (1u << 14)
-#define REACHABLE      (1u << 15)
 
 #define SHALLOW                (1u << 16)
 #define NOT_SHALLOW    (1u << 17)
@@ -337,64 +337,16 @@ static int got_oid(const char *hex, struct object_id *oid)
        return 0;
 }
 
-static int reachable(struct commit *want)
-{
-       struct prio_queue work = { compare_commits_by_commit_date };
-
-       prio_queue_put(&work, want);
-       while (work.nr) {
-               struct commit_list *list;
-               struct commit *commit = prio_queue_get(&work);
-
-               if (commit->object.flags & THEY_HAVE) {
-                       want->object.flags |= COMMON_KNOWN;
-                       break;
-               }
-               if (!commit->object.parsed)
-                       parse_object(the_repository, &commit->object.oid);
-               if (commit->object.flags & REACHABLE)
-                       continue;
-               commit->object.flags |= REACHABLE;
-               if (commit->date < oldest_have)
-                       continue;
-               for (list = commit->parents; list; list = list->next) {
-                       struct commit *parent = list->item;
-                       if (!(parent->object.flags & REACHABLE))
-                               prio_queue_put(&work, parent);
-               }
-       }
-       want->object.flags |= REACHABLE;
-       clear_commit_marks(want, REACHABLE);
-       clear_prio_queue(&work);
-       return (want->object.flags & COMMON_KNOWN);
-}
-
 static int ok_to_give_up(void)
 {
-       int i;
+       uint32_t min_generation = GENERATION_NUMBER_ZERO;
 
        if (!have_obj.nr)
                return 0;
 
-       for (i = 0; i < want_obj.nr; i++) {
-               struct object *want = want_obj.objects[i].item;
-
-               if (want->flags & COMMON_KNOWN)
-                       continue;
-               want = deref_tag(the_repository, want, "a want line", 0);
-               if (!want || want->type != OBJ_COMMIT) {
-                       /* no way to tell if this is reachable by
-                        * looking at the ancestry chain alone, so
-                        * leave a note to ourselves not to worry about
-                        * this object anymore.
-                        */
-                       want_obj.objects[i].item->flags |= COMMON_KNOWN;
-                       continue;
-               }
-               if (!reachable((struct commit *)want))
-                       return 0;
-       }
-       return 1;
+       return can_all_from_reach_with_flag(&want_obj, THEY_HAVE,
+                                           COMMON_KNOWN, oldest_have,
+                                           min_generation);
 }
 
 static int get_common_commits(void)