#include "commit.h"
#include "tag.h"
#include "pkt-line.h"
+#include "remote.h"
+#include "refs.h"
+#include "sha1-array.h"
+#include "diff.h"
+#include "revision.h"
+#include "commit-slab.h"
+#include "sigchain.h"
static int is_shallow = -1;
-static struct stat shallow_stat;
+static struct stat_validity shallow_stat;
static char *alternate_shallow_file;
-void set_alternate_shallow_file(const char *path)
+void set_alternate_shallow_file(const char *path, int override)
{
if (is_shallow != -1)
die("BUG: is_repository_shallow must not be called before set_alternate_shallow_file");
+ if (alternate_shallow_file && !override)
+ return;
free(alternate_shallow_file);
alternate_shallow_file = path ? xstrdup(path) : NULL;
}
* shallow file should be used. We could just open it and it
* will likely fail. But let's do an explicit check instead.
*/
- if (!*path ||
- stat(path, &shallow_stat) ||
- (fp = fopen(path, "r")) == NULL) {
+ if (!*path || (fp = fopen(path, "r")) == NULL) {
+ stat_validity_clear(&shallow_stat);
is_shallow = 0;
return is_shallow;
}
+ stat_validity_update(&shallow_stat, fileno(fp));
is_shallow = 1;
while (fgets(buf, sizeof(buf), fp)) {
struct commit_list *result = NULL;
struct object_array stack = OBJECT_ARRAY_INIT;
struct commit *commit = NULL;
+ struct commit_graft *graft;
while (commit || i < heads->nr || stack.nr) {
struct commit_list *p;
cur_depth = *(int *)commit->util;
}
}
- if (parse_commit(commit))
- die("invalid commit");
+ parse_commit_or_die(commit);
cur_depth++;
- if (cur_depth >= depth) {
+ if ((depth != INFINITE_DEPTH && cur_depth >= depth) ||
+ (is_repository_shallow() && !commit->parents &&
+ (graft = lookup_commit_graft(commit->object.sha1)) != NULL &&
+ graft->nr_parent < 0)) {
commit_list_insert(commit, &result);
commit->object.flags |= shallow_flag;
commit = NULL;
void check_shallow_file_for_update(void)
{
- struct stat st;
-
- if (!is_shallow)
- return;
- else if (is_shallow == -1)
+ if (is_shallow == -1)
die("BUG: shallow must be initialized by now");
- if (stat(git_path("shallow"), &st))
- die("shallow file was removed during fetch");
- else if (st.st_mtime != shallow_stat.st_mtime
-#ifdef USE_NSEC
- || ST_MTIME_NSEC(st) != ST_MTIME_NSEC(shallow_stat)
-#endif
- )
- die("shallow file was changed during fetch");
+ if (!stat_validity_check(&shallow_stat, git_path("shallow")))
+ die("shallow file has changed since we read it");
}
+#define SEEN_ONLY 1
+#define VERBOSE 2
+
struct write_shallow_data {
struct strbuf *out;
int use_pack_protocol;
int count;
+ unsigned flags;
};
static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
const char *hex = sha1_to_hex(graft->sha1);
if (graft->nr_parent != -1)
return 0;
+ if (data->flags & SEEN_ONLY) {
+ struct commit *c = lookup_commit(graft->sha1);
+ if (!c || !(c->object.flags & SEEN)) {
+ if (data->flags & VERBOSE)
+ printf("Removing %s from .git/shallow\n",
+ sha1_to_hex(c->object.sha1));
+ return 0;
+ }
+ }
data->count++;
if (data->use_pack_protocol)
packet_buf_write(data->out, "shallow %s", hex);
return 0;
}
-int write_shallow_commits(struct strbuf *out, int use_pack_protocol)
+static int write_shallow_commits_1(struct strbuf *out, int use_pack_protocol,
+ const struct sha1_array *extra,
+ unsigned flags)
{
struct write_shallow_data data;
+ int i;
data.out = out;
data.use_pack_protocol = use_pack_protocol;
data.count = 0;
+ data.flags = flags;
for_each_commit_graft(write_one_shallow, &data);
+ if (!extra)
+ return data.count;
+ for (i = 0; i < extra->nr; i++) {
+ strbuf_addstr(out, sha1_to_hex(extra->sha1[i]));
+ strbuf_addch(out, '\n');
+ data.count++;
+ }
return data.count;
}
-char *setup_temporary_shallow(void)
+int write_shallow_commits(struct strbuf *out, int use_pack_protocol,
+ const struct sha1_array *extra)
{
+ return write_shallow_commits_1(out, use_pack_protocol, extra, 0);
+}
+
+static struct strbuf temporary_shallow = STRBUF_INIT;
+
+static void remove_temporary_shallow(void)
+{
+ if (temporary_shallow.len) {
+ unlink_or_warn(temporary_shallow.buf);
+ strbuf_reset(&temporary_shallow);
+ }
+}
+
+static void remove_temporary_shallow_on_signal(int signo)
+{
+ remove_temporary_shallow();
+ sigchain_pop(signo);
+ raise(signo);
+}
+
+const char *setup_temporary_shallow(const struct sha1_array *extra)
+{
+ static int installed_handler;
struct strbuf sb = STRBUF_INIT;
int fd;
- if (write_shallow_commits(&sb, 0)) {
- struct strbuf path = STRBUF_INIT;
- strbuf_addstr(&path, git_path("shallow_XXXXXX"));
- fd = xmkstemp(path.buf);
+ if (temporary_shallow.len)
+ die("BUG: attempt to create two temporary shallow files");
+
+ if (write_shallow_commits(&sb, 0, extra)) {
+ strbuf_addstr(&temporary_shallow, git_path("shallow_XXXXXX"));
+ fd = xmkstemp(temporary_shallow.buf);
+
+ if (!installed_handler) {
+ atexit(remove_temporary_shallow);
+ sigchain_push_common(remove_temporary_shallow_on_signal);
+ }
+
if (write_in_full(fd, sb.buf, sb.len) != sb.len)
die_errno("failed to write to %s",
- path.buf);
+ temporary_shallow.buf);
close(fd);
strbuf_release(&sb);
- return strbuf_detach(&path, NULL);
+ return temporary_shallow.buf;
}
/*
* is_repository_shallow() sees empty string as "no shallow
* file".
*/
- return xstrdup("");
+ return temporary_shallow.buf;
}
void setup_alternate_shallow(struct lock_file *shallow_lock,
- const char **alternate_shallow_file)
+ const char **alternate_shallow_file,
+ const struct sha1_array *extra)
{
struct strbuf sb = STRBUF_INIT;
int fd;
- check_shallow_file_for_update();
fd = hold_lock_file_for_update(shallow_lock, git_path("shallow"),
LOCK_DIE_ON_ERROR);
- if (write_shallow_commits(&sb, 0)) {
+ check_shallow_file_for_update();
+ if (write_shallow_commits(&sb, 0, extra)) {
if (write_in_full(fd, sb.buf, sb.len) != sb.len)
die_errno("failed to write to %s",
shallow_lock->filename);
*alternate_shallow_file = "";
strbuf_release(&sb);
}
+
+static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
+{
+ int fd = *(int *)cb;
+ if (graft->nr_parent == -1)
+ packet_write(fd, "shallow %s\n", sha1_to_hex(graft->sha1));
+ return 0;
+}
+
+void advertise_shallow_grafts(int fd)
+{
+ if (!is_repository_shallow())
+ return;
+ for_each_commit_graft(advertise_shallow_grafts_cb, &fd);
+}
+
+/*
+ * mark_reachable_objects() should have been run prior to this and all
+ * reachable commits marked as "SEEN".
+ */
+void prune_shallow(int show_only)
+{
+ static struct lock_file shallow_lock;
+ struct strbuf sb = STRBUF_INIT;
+ int fd;
+
+ if (show_only) {
+ write_shallow_commits_1(&sb, 0, NULL, SEEN_ONLY | VERBOSE);
+ strbuf_release(&sb);
+ return;
+ }
+ fd = hold_lock_file_for_update(&shallow_lock, git_path("shallow"),
+ LOCK_DIE_ON_ERROR);
+ check_shallow_file_for_update();
+ if (write_shallow_commits_1(&sb, 0, NULL, SEEN_ONLY)) {
+ if (write_in_full(fd, sb.buf, sb.len) != sb.len)
+ die_errno("failed to write to %s",
+ shallow_lock.filename);
+ commit_lock_file(&shallow_lock);
+ } else {
+ unlink(git_path("shallow"));
+ rollback_lock_file(&shallow_lock);
+ }
+ strbuf_release(&sb);
+}
+
+#define TRACE_KEY "GIT_TRACE_SHALLOW"
+
+/*
+ * Step 1, split sender shallow commits into "ours" and "theirs"
+ * Step 2, clean "ours" based on .git/shallow
+ */
+void prepare_shallow_info(struct shallow_info *info, struct sha1_array *sa)
+{
+ int i;
+ trace_printf_key(TRACE_KEY, "shallow: prepare_shallow_info\n");
+ memset(info, 0, sizeof(*info));
+ info->shallow = sa;
+ if (!sa)
+ return;
+ info->ours = xmalloc(sizeof(*info->ours) * sa->nr);
+ info->theirs = xmalloc(sizeof(*info->theirs) * sa->nr);
+ for (i = 0; i < sa->nr; i++) {
+ if (has_sha1_file(sa->sha1[i])) {
+ struct commit_graft *graft;
+ graft = lookup_commit_graft(sa->sha1[i]);
+ if (graft && graft->nr_parent < 0)
+ continue;
+ info->ours[info->nr_ours++] = i;
+ } else
+ info->theirs[info->nr_theirs++] = i;
+ }
+}
+
+void clear_shallow_info(struct shallow_info *info)
+{
+ free(info->ours);
+ free(info->theirs);
+}
+
+/* Step 4, remove non-existent ones in "theirs" after getting the pack */
+
+void remove_nonexistent_theirs_shallow(struct shallow_info *info)
+{
+ unsigned char (*sha1)[20] = info->shallow->sha1;
+ int i, dst;
+ trace_printf_key(TRACE_KEY, "shallow: remove_nonexistent_theirs_shallow\n");
+ for (i = dst = 0; i < info->nr_theirs; i++) {
+ if (i != dst)
+ info->theirs[dst] = info->theirs[i];
+ if (has_sha1_file(sha1[info->theirs[i]]))
+ dst++;
+ }
+ info->nr_theirs = dst;
+}
+
+define_commit_slab(ref_bitmap, uint32_t *);
+
+struct paint_info {
+ struct ref_bitmap ref_bitmap;
+ unsigned nr_bits;
+ char **slab;
+ char *free, *end;
+ unsigned slab_count;
+};
+
+static uint32_t *paint_alloc(struct paint_info *info)
+{
+ unsigned nr = (info->nr_bits + 31) / 32;
+ unsigned size = nr * sizeof(uint32_t);
+ void *p;
+ if (!info->slab_count || info->free + size > info->end) {
+ info->slab_count++;
+ info->slab = xrealloc(info->slab,
+ info->slab_count * sizeof(*info->slab));
+ info->free = xmalloc(COMMIT_SLAB_SIZE);
+ info->slab[info->slab_count - 1] = info->free;
+ info->end = info->free + COMMIT_SLAB_SIZE;
+ }
+ p = info->free;
+ info->free += size;
+ return p;
+}
+
+/*
+ * Given a commit SHA-1, walk down to parents until either SEEN,
+ * UNINTERESTING or BOTTOM is hit. Set the id-th bit in ref_bitmap for
+ * all walked commits.
+ */
+static void paint_down(struct paint_info *info, const unsigned char *sha1,
+ int id)
+{
+ unsigned int i, nr;
+ struct commit_list *head = NULL;
+ int bitmap_nr = (info->nr_bits + 31) / 32;
+ int bitmap_size = bitmap_nr * sizeof(uint32_t);
+ uint32_t *tmp = xmalloc(bitmap_size); /* to be freed before return */
+ uint32_t *bitmap = paint_alloc(info);
+ struct commit *c = lookup_commit_reference_gently(sha1, 1);
+ if (!c)
+ return;
+ memset(bitmap, 0, bitmap_size);
+ bitmap[id / 32] |= (1 << (id % 32));
+ commit_list_insert(c, &head);
+ while (head) {
+ struct commit_list *p;
+ struct commit *c = head->item;
+ uint32_t **refs = ref_bitmap_at(&info->ref_bitmap, c);
+
+ p = head;
+ head = head->next;
+ free(p);
+
+ /* XXX check "UNINTERESTING" from pack bitmaps if available */
+ if (c->object.flags & (SEEN | UNINTERESTING))
+ continue;
+ else
+ c->object.flags |= SEEN;
+
+ if (*refs == NULL)
+ *refs = bitmap;
+ else {
+ memcpy(tmp, *refs, bitmap_size);
+ for (i = 0; i < bitmap_nr; i++)
+ tmp[i] |= bitmap[i];
+ if (memcmp(tmp, *refs, bitmap_size)) {
+ *refs = paint_alloc(info);
+ memcpy(*refs, tmp, bitmap_size);
+ }
+ }
+
+ if (c->object.flags & BOTTOM)
+ continue;
+
+ if (parse_commit(c))
+ die("unable to parse commit %s",
+ sha1_to_hex(c->object.sha1));
+
+ for (p = c->parents; p; p = p->next) {
+ uint32_t **p_refs = ref_bitmap_at(&info->ref_bitmap,
+ p->item);
+ if (p->item->object.flags & SEEN)
+ continue;
+ if (*p_refs == NULL || *p_refs == *refs)
+ *p_refs = *refs;
+ commit_list_insert(p->item, &head);
+ }
+ }
+
+ nr = get_max_object_index();
+ for (i = 0; i < nr; i++) {
+ struct object *o = get_indexed_object(i);
+ if (o && o->type == OBJ_COMMIT)
+ o->flags &= ~SEEN;
+ }
+
+ free(tmp);
+}
+
+static int mark_uninteresting(const char *refname,
+ const unsigned char *sha1,
+ int flags, void *cb_data)
+{
+ struct commit *commit = lookup_commit_reference_gently(sha1, 1);
+ if (!commit)
+ return 0;
+ commit->object.flags |= UNINTERESTING;
+ mark_parents_uninteresting(commit);
+ return 0;
+}
+
+static void post_assign_shallow(struct shallow_info *info,
+ struct ref_bitmap *ref_bitmap,
+ int *ref_status);
+/*
+ * Step 6(+7), associate shallow commits with new refs
+ *
+ * info->ref must be initialized before calling this function.
+ *
+ * If used is not NULL, it's an array of info->shallow->nr
+ * bitmaps. The n-th bit set in the m-th bitmap if ref[n] needs the
+ * m-th shallow commit from info->shallow.
+ *
+ * If used is NULL, "ours" and "theirs" are updated. And if ref_status
+ * is not NULL it's an array of ref->nr ints. ref_status[i] is true if
+ * the ref needs some shallow commits from either info->ours or
+ * info->theirs.
+ */
+void assign_shallow_commits_to_refs(struct shallow_info *info,
+ uint32_t **used, int *ref_status)
+{
+ unsigned char (*sha1)[20] = info->shallow->sha1;
+ struct sha1_array *ref = info->ref;
+ unsigned int i, nr;
+ int *shallow, nr_shallow = 0;
+ struct paint_info pi;
+
+ trace_printf_key(TRACE_KEY, "shallow: assign_shallow_commits_to_refs\n");
+ shallow = xmalloc(sizeof(*shallow) * (info->nr_ours + info->nr_theirs));
+ for (i = 0; i < info->nr_ours; i++)
+ shallow[nr_shallow++] = info->ours[i];
+ for (i = 0; i < info->nr_theirs; i++)
+ shallow[nr_shallow++] = info->theirs[i];
+
+ /*
+ * Prepare the commit graph to track what refs can reach what
+ * (new) shallow commits.
+ */
+ nr = get_max_object_index();
+ for (i = 0; i < nr; i++) {
+ struct object *o = get_indexed_object(i);
+ if (!o || o->type != OBJ_COMMIT)
+ continue;
+
+ o->flags &= ~(UNINTERESTING | BOTTOM | SEEN);
+ }
+
+ memset(&pi, 0, sizeof(pi));
+ init_ref_bitmap(&pi.ref_bitmap);
+ pi.nr_bits = ref->nr;
+
+ /*
+ * "--not --all" to cut short the traversal if new refs
+ * connect to old refs. If not (e.g. force ref updates) it'll
+ * have to go down to the current shallow commits.
+ */
+ head_ref(mark_uninteresting, NULL);
+ for_each_ref(mark_uninteresting, NULL);
+
+ /* Mark potential bottoms so we won't go out of bound */
+ for (i = 0; i < nr_shallow; i++) {
+ struct commit *c = lookup_commit(sha1[shallow[i]]);
+ c->object.flags |= BOTTOM;
+ }
+
+ for (i = 0; i < ref->nr; i++)
+ paint_down(&pi, ref->sha1[i], i);
+
+ if (used) {
+ int bitmap_size = ((pi.nr_bits + 31) / 32) * sizeof(uint32_t);
+ memset(used, 0, sizeof(*used) * info->shallow->nr);
+ for (i = 0; i < nr_shallow; i++) {
+ const struct commit *c = lookup_commit(sha1[shallow[i]]);
+ uint32_t **map = ref_bitmap_at(&pi.ref_bitmap, c);
+ if (*map)
+ used[shallow[i]] = xmemdupz(*map, bitmap_size);
+ }
+ /*
+ * unreachable shallow commits are not removed from
+ * "ours" and "theirs". The user is supposed to run
+ * step 7 on every ref separately and not trust "ours"
+ * and "theirs" any more.
+ */
+ } else
+ post_assign_shallow(info, &pi.ref_bitmap, ref_status);
+
+ clear_ref_bitmap(&pi.ref_bitmap);
+ for (i = 0; i < pi.slab_count; i++)
+ free(pi.slab[i]);
+ free(pi.slab);
+ free(shallow);
+}
+
+struct commit_array {
+ struct commit **commits;
+ int nr, alloc;
+};
+
+static int add_ref(const char *refname,
+ const unsigned char *sha1, int flags, void *cb_data)
+{
+ struct commit_array *ca = cb_data;
+ ALLOC_GROW(ca->commits, ca->nr + 1, ca->alloc);
+ ca->commits[ca->nr] = lookup_commit_reference_gently(sha1, 1);
+ if (ca->commits[ca->nr])
+ ca->nr++;
+ return 0;
+}
+
+static void update_refstatus(int *ref_status, int nr, uint32_t *bitmap)
+{
+ int i;
+ if (!ref_status)
+ return;
+ for (i = 0; i < nr; i++)
+ if (bitmap[i / 32] & (1 << (i % 32)))
+ ref_status[i]++;
+}
+
+/*
+ * Step 7, reachability test on "ours" at commit level
+ */
+static void post_assign_shallow(struct shallow_info *info,
+ struct ref_bitmap *ref_bitmap,
+ int *ref_status)
+{
+ unsigned char (*sha1)[20] = info->shallow->sha1;
+ struct commit *c;
+ uint32_t **bitmap;
+ int dst, i, j;
+ int bitmap_nr = (info->ref->nr + 31) / 32;
+ struct commit_array ca;
+
+ trace_printf_key(TRACE_KEY, "shallow: post_assign_shallow\n");
+ if (ref_status)
+ memset(ref_status, 0, sizeof(*ref_status) * info->ref->nr);
+
+ /* Remove unreachable shallow commits from "theirs" */
+ for (i = dst = 0; i < info->nr_theirs; i++) {
+ if (i != dst)
+ info->theirs[dst] = info->theirs[i];
+ c = lookup_commit(sha1[info->theirs[i]]);
+ bitmap = ref_bitmap_at(ref_bitmap, c);
+ if (!*bitmap)
+ continue;
+ for (j = 0; j < bitmap_nr; j++)
+ if (bitmap[0][j]) {
+ update_refstatus(ref_status, info->ref->nr, *bitmap);
+ dst++;
+ break;
+ }
+ }
+ info->nr_theirs = dst;
+
+ memset(&ca, 0, sizeof(ca));
+ head_ref(add_ref, &ca);
+ for_each_ref(add_ref, &ca);
+
+ /* Remove unreachable shallow commits from "ours" */
+ for (i = dst = 0; i < info->nr_ours; i++) {
+ if (i != dst)
+ info->ours[dst] = info->ours[i];
+ c = lookup_commit(sha1[info->ours[i]]);
+ bitmap = ref_bitmap_at(ref_bitmap, c);
+ if (!*bitmap)
+ continue;
+ for (j = 0; j < bitmap_nr; j++)
+ if (bitmap[0][j] &&
+ /* Step 7, reachability test at commit level */
+ !in_merge_bases_many(c, ca.nr, ca.commits)) {
+ update_refstatus(ref_status, info->ref->nr, *bitmap);
+ dst++;
+ break;
+ }
+ }
+ info->nr_ours = dst;
+
+ free(ca.commits);
+}
+
+/* (Delayed) step 7, reachability test at commit level */
+int delayed_reachability_test(struct shallow_info *si, int c)
+{
+ if (si->need_reachability_test[c]) {
+ struct commit *commit = lookup_commit(si->shallow->sha1[c]);
+
+ if (!si->commits) {
+ struct commit_array ca;
+ memset(&ca, 0, sizeof(ca));
+ head_ref(add_ref, &ca);
+ for_each_ref(add_ref, &ca);
+ si->commits = ca.commits;
+ si->nr_commits = ca.nr;
+ }
+
+ si->reachable[c] = in_merge_bases_many(commit,
+ si->nr_commits,
+ si->commits);
+ si->need_reachability_test[c] = 0;
+ }
+ return si->reachable[c];
+}