[RFC PATCH 01/13] commit-reach: move walk methods from commit.c
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
---
Makefile | 1 +
commit-reach.c | 359 +++++++++++++++++++++++++++++++++++++++++++++++++
commit-reach.h | 41 ++++++
commit.c | 358 ------------------------------------------------
4 files changed, 401 insertions(+), 358 deletions(-)
create mode 100644 commit-reach.c
create mode 100644 commit-reach.h
diff --git a/Makefile b/Makefile
index 0cb6590f24..89ad873ce0 100644
--- a/Makefile
+++ b/Makefile
@@ -828,6 +828,7 @@ 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
diff --git a/commit-reach.c b/commit-reach.c
new file mode 100644
index 0000000000..1438393165
--- /dev/null
+++ b/commit-reach.c
@@ -0,0 +1,359 @@
+#include "cache.h"
+#include "prio-queue.h"
+#include "commit-reach.h"
+
+/* 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;
+
+ 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 (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;
+}
diff --git a/commit-reach.h b/commit-reach.h
new file mode 100644
index 0000000000..244f48c5f2
--- /dev/null
+++ b/commit-reach.h
@@ -0,0 +1,41 @@
+#ifndef __COMMIT_REACH_H__
+#define __COMMIT_REACH_H__
+
+#include "commit.h"
+
+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);
+
+#endif
diff --git a/commit.c b/commit.c
index 598cf21cee..d4ddaf4879 100644
--- a/commit.c
+++ b/commit.c
@@ -818,364 +818,6 @@ 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;
-
- 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 (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;
--
2.18.0.118.gd4f65b8d14
Derrick Stolee <dstolee@microsoft.com>