Squashed 'third_party/git/' content from commit cb71568594

git-subtree-dir: third_party/git
git-subtree-split: cb715685942260375e1eb8153b0768a376e4ece7

1 files changed, 505 insertions, 0 deletions

diff --git a/bundle.c b/bundle.c
new file mode 100644
index 0000000000..b5d21cd80f
--- /dev/null
+++ b/bundle.c
@@ -0,0 +1,505 @@
+#include "cache.h"
+#include "lockfile.h"
+#include "bundle.h"
+#include "object-store.h"
+#include "repository.h"
+#include "object.h"
+#include "commit.h"
+#include "diff.h"
+#include "revision.h"
+#include "list-objects.h"
+#include "run-command.h"
+#include "refs.h"
+#include "argv-array.h"
+
+static const char bundle_signature[] = "# v2 git bundle\n";
+
+static void add_to_ref_list(const struct object_id *oid, const char *name,
+		struct ref_list *list)
+{
+	ALLOC_GROW(list->list, list->nr + 1, list->alloc);
+	oidcpy(&list->list[list->nr].oid, oid);
+	list->list[list->nr].name = xstrdup(name);
+	list->nr++;
+}
+
+static int parse_bundle_header(int fd, struct bundle_header *header,
+			       const char *report_path)
+{
+	struct strbuf buf = STRBUF_INIT;
+	int status = 0;
+
+	/* The bundle header begins with the signature */
+	if (strbuf_getwholeline_fd(&buf, fd, '\n') ||
+	    strcmp(buf.buf, bundle_signature)) {
+		if (report_path)
+			error(_("'%s' does not look like a v2 bundle file"),
+			      report_path);
+		status = -1;
+		goto abort;
+	}
+
+	/* The bundle header ends with an empty line */
+	while (!strbuf_getwholeline_fd(&buf, fd, '\n') &&
+	       buf.len && buf.buf[0] != '\n') {
+		struct object_id oid;
+		int is_prereq = 0;
+		const char *p;
+
+		if (*buf.buf == '-') {
+			is_prereq = 1;
+			strbuf_remove(&buf, 0, 1);
+		}
+		strbuf_rtrim(&buf);
+
+		/*
+		 * Tip lines have object name, SP, and refname.
+		 * Prerequisites have object name that is optionally
+		 * followed by SP and subject line.
+		 */
+		if (parse_oid_hex(buf.buf, &oid, &p) ||
+		    (*p && !isspace(*p)) ||
+		    (!is_prereq && !*p)) {
+			if (report_path)
+				error(_("unrecognized header: %s%s (%d)"),
+				      (is_prereq ? "-" : ""), buf.buf, (int)buf.len);
+			status = -1;
+			break;
+		} else {
+			if (is_prereq)
+				add_to_ref_list(&oid, "", &header->prerequisites);
+			else
+				add_to_ref_list(&oid, p + 1, &header->references);
+		}
+	}
+
+ abort:
+	if (status) {
+		close(fd);
+		fd = -1;
+	}
+	strbuf_release(&buf);
+	return fd;
+}
+
+int read_bundle_header(const char *path, struct bundle_header *header)
+{
+	int fd = open(path, O_RDONLY);
+
+	if (fd < 0)
+		return error(_("could not open '%s'"), path);
+	return parse_bundle_header(fd, header, path);
+}
+
+int is_bundle(const char *path, int quiet)
+{
+	struct bundle_header header;
+	int fd = open(path, O_RDONLY);
+
+	if (fd < 0)
+		return 0;
+	memset(&header, 0, sizeof(header));
+	fd = parse_bundle_header(fd, &header, quiet ? NULL : path);
+	if (fd >= 0)
+		close(fd);
+	return (fd >= 0);
+}
+
+static int list_refs(struct ref_list *r, int argc, const char **argv)
+{
+	int i;
+
+	for (i = 0; i < r->nr; i++) {
+		if (argc > 1) {
+			int j;
+			for (j = 1; j < argc; j++)
+				if (!strcmp(r->list[i].name, argv[j]))
+					break;
+			if (j == argc)
+				continue;
+		}
+		printf("%s %s\n", oid_to_hex(&r->list[i].oid),
+				r->list[i].name);
+	}
+	return 0;
+}
+
+/* Remember to update object flag allocation in object.h */
+#define PREREQ_MARK (1u<<16)
+
+int verify_bundle(struct repository *r,
+		  struct bundle_header *header,
+		  int verbose)
+{
+	/*
+	 * Do fast check, then if any prereqs are missing then go line by line
+	 * to be verbose about the errors
+	 */
+	struct ref_list *p = &header->prerequisites;
+	struct rev_info revs;
+	const char *argv[] = {NULL, "--all", NULL};
+	struct commit *commit;
+	int i, ret = 0, req_nr;
+	const char *message = _("Repository lacks these prerequisite commits:");
+
+	if (!r || !r->objects || !r->objects->odb)
+		return error(_("need a repository to verify a bundle"));
+
+	repo_init_revisions(r, &revs, NULL);
+	for (i = 0; i < p->nr; i++) {
+		struct ref_list_entry *e = p->list + i;
+		struct object *o = parse_object(r, &e->oid);
+		if (o) {
+			o->flags |= PREREQ_MARK;
+			add_pending_object(&revs, o, e->name);
+			continue;
+		}
+		if (++ret == 1)
+			error("%s", message);
+		error("%s %s", oid_to_hex(&e->oid), e->name);
+	}
+	if (revs.pending.nr != p->nr)
+		return ret;
+	req_nr = revs.pending.nr;
+	setup_revisions(2, argv, &revs, NULL);
+
+	if (prepare_revision_walk(&revs))
+		die(_("revision walk setup failed"));
+
+	i = req_nr;
+	while (i && (commit = get_revision(&revs)))
+		if (commit->object.flags & PREREQ_MARK)
+			i--;
+
+	for (i = 0; i < p->nr; i++) {
+		struct ref_list_entry *e = p->list + i;
+		struct object *o = parse_object(r, &e->oid);
+		assert(o); /* otherwise we'd have returned early */
+		if (o->flags & SHOWN)
+			continue;
+		if (++ret == 1)
+			error("%s", message);
+		error("%s %s", oid_to_hex(&e->oid), e->name);
+	}
+
+	/* Clean up objects used, as they will be reused. */
+	for (i = 0; i < p->nr; i++) {
+		struct ref_list_entry *e = p->list + i;
+		commit = lookup_commit_reference_gently(r, &e->oid, 1);
+		if (commit)
+			clear_commit_marks(commit, ALL_REV_FLAGS);
+	}
+
+	if (verbose) {
+		struct ref_list *r;
+
+		r = &header->references;
+		printf_ln(Q_("The bundle contains this ref:",
+			     "The bundle contains these %d refs:",
+			     r->nr),
+			  r->nr);
+		list_refs(r, 0, NULL);
+		r = &header->prerequisites;
+		if (!r->nr) {
+			printf_ln(_("The bundle records a complete history."));
+		} else {
+			printf_ln(Q_("The bundle requires this ref:",
+				     "The bundle requires these %d refs:",
+				     r->nr),
+				  r->nr);
+			list_refs(r, 0, NULL);
+		}
+	}
+	return ret;
+}
+
+int list_bundle_refs(struct bundle_header *header, int argc, const char **argv)
+{
+	return list_refs(&header->references, argc, argv);
+}
+
+static int is_tag_in_date_range(struct object *tag, struct rev_info *revs)
+{
+	unsigned long size;
+	enum object_type type;
+	char *buf = NULL, *line, *lineend;
+	timestamp_t date;
+	int result = 1;
+
+	if (revs->max_age == -1 && revs->min_age == -1)
+		goto out;
+
+	buf = read_object_file(&tag->oid, &type, &size);
+	if (!buf)
+		goto out;
+	line = memmem(buf, size, "\ntagger ", 8);
+	if (!line++)
+		goto out;
+	lineend = memchr(line, '\n', buf + size - line);
+	line = memchr(line, '>', lineend ? lineend - line : buf + size - line);
+	if (!line++)
+		goto out;
+	date = parse_timestamp(line, NULL, 10);
+	result = (revs->max_age == -1 || revs->max_age < date) &&
+		(revs->min_age == -1 || revs->min_age > date);
+out:
+	free(buf);
+	return result;
+}
+
+
+/* Write the pack data to bundle_fd */
+static int write_pack_data(int bundle_fd, struct rev_info *revs)
+{
+	struct child_process pack_objects = CHILD_PROCESS_INIT;
+	int i;
+
+	argv_array_pushl(&pack_objects.args,
+			 "pack-objects", "--all-progress-implied",
+			 "--stdout", "--thin", "--delta-base-offset",
+			 NULL);
+	pack_objects.in = -1;
+	pack_objects.out = bundle_fd;
+	pack_objects.git_cmd = 1;
+
+	/*
+	 * start_command() will close our descriptor if it's >1. Duplicate it
+	 * to avoid surprising the caller.
+	 */
+	if (pack_objects.out > 1) {
+		pack_objects.out = dup(pack_objects.out);
+		if (pack_objects.out < 0) {
+			error_errno(_("unable to dup bundle descriptor"));
+			child_process_clear(&pack_objects);
+			return -1;
+		}
+	}
+
+	if (start_command(&pack_objects))
+		return error(_("Could not spawn pack-objects"));
+
+	for (i = 0; i < revs->pending.nr; i++) {
+		struct object *object = revs->pending.objects[i].item;
+		if (object->flags & UNINTERESTING)
+			write_or_die(pack_objects.in, "^", 1);
+		write_or_die(pack_objects.in, oid_to_hex(&object->oid), GIT_SHA1_HEXSZ);
+		write_or_die(pack_objects.in, "\n", 1);
+	}
+	close(pack_objects.in);
+	if (finish_command(&pack_objects))
+		return error(_("pack-objects died"));
+	return 0;
+}
+
+static int compute_and_write_prerequisites(int bundle_fd,
+					   struct rev_info *revs,
+					   int argc, const char **argv)
+{
+	struct child_process rls = CHILD_PROCESS_INIT;
+	struct strbuf buf = STRBUF_INIT;
+	FILE *rls_fout;
+	int i;
+
+	argv_array_pushl(&rls.args,
+			 "rev-list", "--boundary", "--pretty=oneline",
+			 NULL);
+	for (i = 1; i < argc; i++)
+		argv_array_push(&rls.args, argv[i]);
+	rls.out = -1;
+	rls.git_cmd = 1;
+	if (start_command(&rls))
+		return -1;
+	rls_fout = xfdopen(rls.out, "r");
+	while (strbuf_getwholeline(&buf, rls_fout, '\n') != EOF) {
+		struct object_id oid;
+		if (buf.len > 0 && buf.buf[0] == '-') {
+			write_or_die(bundle_fd, buf.buf, buf.len);
+			if (!get_oid_hex(buf.buf + 1, &oid)) {
+				struct object *object = parse_object_or_die(&oid,
+									    buf.buf);
+				object->flags |= UNINTERESTING;
+				add_pending_object(revs, object, buf.buf);
+			}
+		} else if (!get_oid_hex(buf.buf, &oid)) {
+			struct object *object = parse_object_or_die(&oid,
+								    buf.buf);
+			object->flags |= SHOWN;
+		}
+	}
+	strbuf_release(&buf);
+	fclose(rls_fout);
+	if (finish_command(&rls))
+		return error(_("rev-list died"));
+	return 0;
+}
+
+/*
+ * Write out bundle refs based on the tips already
+ * parsed into revs.pending. As a side effect, may
+ * manipulate revs.pending to include additional
+ * necessary objects (like tags).
+ *
+ * Returns the number of refs written, or negative
+ * on error.
+ */
+static int write_bundle_refs(int bundle_fd, struct rev_info *revs)
+{
+	int i;
+	int ref_count = 0;
+
+	for (i = 0; i < revs->pending.nr; i++) {
+		struct object_array_entry *e = revs->pending.objects + i;
+		struct object_id oid;
+		char *ref;
+		const char *display_ref;
+		int flag;
+
+		if (e->item->flags & UNINTERESTING)
+			continue;
+		if (dwim_ref(e->name, strlen(e->name), &oid, &ref) != 1)
+			goto skip_write_ref;
+		if (read_ref_full(e->name, RESOLVE_REF_READING, &oid, &flag))
+			flag = 0;
+		display_ref = (flag & REF_ISSYMREF) ? e->name : ref;
+
+		if (e->item->type == OBJ_TAG &&
+				!is_tag_in_date_range(e->item, revs)) {
+			e->item->flags |= UNINTERESTING;
+			goto skip_write_ref;
+		}
+
+		/*
+		 * Make sure the refs we wrote out is correct; --max-count and
+		 * other limiting options could have prevented all the tips
+		 * from getting output.
+		 *
+		 * Non commit objects such as tags and blobs do not have
+		 * this issue as they are not affected by those extra
+		 * constraints.
+		 */
+		if (!(e->item->flags & SHOWN) && e->item->type == OBJ_COMMIT) {
+			warning(_("ref '%s' is excluded by the rev-list options"),
+				e->name);
+			goto skip_write_ref;
+		}
+		/*
+		 * If you run "git bundle create bndl v1.0..v2.0", the
+		 * name of the positive ref is "v2.0" but that is the
+		 * commit that is referenced by the tag, and not the tag
+		 * itself.
+		 */
+		if (!oideq(&oid, &e->item->oid)) {
+			/*
+			 * Is this the positive end of a range expressed
+			 * in terms of a tag (e.g. v2.0 from the range
+			 * "v1.0..v2.0")?
+			 */
+			struct commit *one = lookup_commit_reference(revs->repo, &oid);
+			struct object *obj;
+
+			if (e->item == &(one->object)) {
+				/*
+				 * Need to include e->name as an
+				 * independent ref to the pack-objects
+				 * input, so that the tag is included
+				 * in the output; otherwise we would
+				 * end up triggering "empty bundle"
+				 * error.
+				 */
+				obj = parse_object_or_die(&oid, e->name);
+				obj->flags |= SHOWN;
+				add_pending_object(revs, obj, e->name);
+			}
+			goto skip_write_ref;
+		}
+
+		ref_count++;
+		write_or_die(bundle_fd, oid_to_hex(&e->item->oid), 40);
+		write_or_die(bundle_fd, " ", 1);
+		write_or_die(bundle_fd, display_ref, strlen(display_ref));
+		write_or_die(bundle_fd, "\n", 1);
+ skip_write_ref:
+		free(ref);
+	}
+
+	/* end header */
+	write_or_die(bundle_fd, "\n", 1);
+	return ref_count;
+}
+
+int create_bundle(struct repository *r, const char *path,
+		  int argc, const char **argv)
+{
+	struct lock_file lock = LOCK_INIT;
+	int bundle_fd = -1;
+	int bundle_to_stdout;
+	int ref_count = 0;
+	struct rev_info revs;
+
+	bundle_to_stdout = !strcmp(path, "-");
+	if (bundle_to_stdout)
+		bundle_fd = 1;
+	else
+		bundle_fd = hold_lock_file_for_update(&lock, path,
+						      LOCK_DIE_ON_ERROR);
+
+	/* write signature */
+	write_or_die(bundle_fd, bundle_signature, strlen(bundle_signature));
+
+	/* init revs to list objects for pack-objects later */
+	save_commit_buffer = 0;
+	repo_init_revisions(r, &revs, NULL);
+
+	/* write prerequisites */
+	if (compute_and_write_prerequisites(bundle_fd, &revs, argc, argv))
+		goto err;
+
+	argc = setup_revisions(argc, argv, &revs, NULL);
+
+	if (argc > 1) {
+		error(_("unrecognized argument: %s"), argv[1]);
+		goto err;
+	}
+
+	object_array_remove_duplicates(&revs.pending);
+
+	ref_count = write_bundle_refs(bundle_fd, &revs);
+	if (!ref_count)
+		die(_("Refusing to create empty bundle."));
+	else if (ref_count < 0)
+		goto err;
+
+	/* write pack */
+	if (write_pack_data(bundle_fd, &revs))
+		goto err;
+
+	if (!bundle_to_stdout) {
+		if (commit_lock_file(&lock))
+			die_errno(_("cannot create '%s'"), path);
+	}
+	return 0;
+err:
+	rollback_lock_file(&lock);
+	return -1;
+}
+
+int unbundle(struct repository *r, struct bundle_header *header,
+	     int bundle_fd, int flags)
+{
+	const char *argv_index_pack[] = {"index-pack",
+					 "--fix-thin", "--stdin", NULL, NULL};
+	struct child_process ip = CHILD_PROCESS_INIT;
+
+	if (flags & BUNDLE_VERBOSE)
+		argv_index_pack[3] = "-v";
+
+	if (verify_bundle(r, header, 0))
+		return -1;
+	ip.argv = argv_index_pack;
+	ip.in = bundle_fd;
+	ip.no_stdout = 1;
+	ip.git_cmd = 1;
+	if (run_command(&ip))
+		return error(_("index-pack died"));
+	return 0;
+}