[thirdparty/git.git] / builtin-reflog.c

#include "cache.h"
#include "builtin.h"
#include "commit.h"
#include "refs.h"
#include "dir.h"
#include "tree-walk.h"
#include "diff.h"
#include "revision.h"
#include "reachable.h"

/*
 * reflog expire
 */

static const char reflog_expire_usage[] =
"git reflog (show|expire) [--verbose] [--dry-run] [--stale-fix] [--expire=<time>] [--expire-unreachable=<time>] [--all] <refs>...";
static const char reflog_delete_usage[] =
"git reflog delete [--verbose] [--dry-run] [--rewrite] [--updateref] <refs>...";

static unsigned long default_reflog_expire;
static unsigned long default_reflog_expire_unreachable;

struct cmd_reflog_expire_cb {
	struct rev_info revs;
	int dry_run;
	int stalefix;
	int rewrite;
	int updateref;
	int verbose;
	unsigned long expire_total;
	unsigned long expire_unreachable;
	int recno;
};

struct expire_reflog_cb {
	FILE *newlog;
	const char *ref;
	struct commit *ref_commit;
	struct cmd_reflog_expire_cb *cmd;
	unsigned char last_kept_sha1[20];
};

struct collected_reflog {
	unsigned char sha1[20];
	char reflog[FLEX_ARRAY];
};
struct collect_reflog_cb {
	struct collected_reflog **e;
	int alloc;
	int nr;
};

#define INCOMPLETE	(1u<<10)
#define STUDYING	(1u<<11)

static int tree_is_complete(const unsigned char *sha1)
{
	struct tree_desc desc;
	struct name_entry entry;
	int complete;
	struct tree *tree;

	tree = lookup_tree(sha1);
	if (!tree)
		return 0;
	if (tree->object.flags & SEEN)
		return 1;
	if (tree->object.flags & INCOMPLETE)
		return 0;

	if (!tree->buffer) {
		enum object_type type;
		unsigned long size;
		void *data = read_sha1_file(sha1, &type, &size);
		if (!data) {
			tree->object.flags |= INCOMPLETE;
			return 0;
		}
		tree->buffer = data;
		tree->size = size;
	}
	init_tree_desc(&desc, tree->buffer, tree->size);
	complete = 1;
	while (tree_entry(&desc, &entry)) {
		if (!has_sha1_file(entry.sha1) ||
		    (S_ISDIR(entry.mode) && !tree_is_complete(entry.sha1))) {
			tree->object.flags |= INCOMPLETE;
			complete = 0;
		}
	}
	free(tree->buffer);
	tree->buffer = NULL;

	if (complete)
		tree->object.flags |= SEEN;
	return complete;
}

static int commit_is_complete(struct commit *commit)
{
	struct object_array study;
	struct object_array found;
	int is_incomplete = 0;
	int i;

	/* early return */
	if (commit->object.flags & SEEN)
		return 1;
	if (commit->object.flags & INCOMPLETE)
		return 0;
	/*
	 * Find all commits that are reachable and are not marked as
	 * SEEN.  Then make sure the trees and blobs contained are
	 * complete.  After that, mark these commits also as SEEN.
	 * If some of the objects that are needed to complete this
	 * commit are missing, mark this commit as INCOMPLETE.
	 */
	memset(&study, 0, sizeof(study));
	memset(&found, 0, sizeof(found));
	add_object_array(&commit->object, NULL, &study);
	add_object_array(&commit->object, NULL, &found);
	commit->object.flags |= STUDYING;
	while (study.nr) {
		struct commit *c;
		struct commit_list *parent;

		c = (struct commit *)study.objects[--study.nr].item;
		if (!c->object.parsed && !parse_object(c->object.sha1))
			c->object.flags |= INCOMPLETE;

		if (c->object.flags & INCOMPLETE) {
			is_incomplete = 1;
			break;
		}
		else if (c->object.flags & SEEN)
			continue;
		for (parent = c->parents; parent; parent = parent->next) {
			struct commit *p = parent->item;
			if (p->object.flags & STUDYING)
				continue;
			p->object.flags |= STUDYING;
			add_object_array(&p->object, NULL, &study);
			add_object_array(&p->object, NULL, &found);
		}
	}
	if (!is_incomplete) {
		/*
		 * make sure all commits in "found" array have all the
		 * necessary objects.
		 */
		for (i = 0; i < found.nr; i++) {
			struct commit *c =
				(struct commit *)found.objects[i].item;
			if (!tree_is_complete(c->tree->object.sha1)) {
				is_incomplete = 1;
				c->object.flags |= INCOMPLETE;
			}
		}
		if (!is_incomplete) {
			/* mark all found commits as complete, iow SEEN */
			for (i = 0; i < found.nr; i++)
				found.objects[i].item->flags |= SEEN;
		}
	}
	/* clear flags from the objects we traversed */
	for (i = 0; i < found.nr; i++)
		found.objects[i].item->flags &= ~STUDYING;
	if (is_incomplete)
		commit->object.flags |= INCOMPLETE;
	else {
		/*
		 * If we come here, we have (1) traversed the ancestry chain
		 * from the "commit" until we reach SEEN commits (which are
		 * known to be complete), and (2) made sure that the commits
		 * encountered during the above traversal refer to trees that
		 * are complete.  Which means that we know *all* the commits
		 * we have seen during this process are complete.
		 */
		for (i = 0; i < found.nr; i++)
			found.objects[i].item->flags |= SEEN;
	}
	/* free object arrays */
	free(study.objects);
	free(found.objects);
	return !is_incomplete;
}

static int keep_entry(struct commit **it, unsigned char *sha1)
{
	struct commit *commit;

	if (is_null_sha1(sha1))
		return 1;
	commit = lookup_commit_reference_gently(sha1, 1);
	if (!commit)
		return 0;

	/*
	 * Make sure everything in this commit exists.
	 *
	 * We have walked all the objects reachable from the refs
	 * and cache earlier.  The commits reachable by this commit
	 * must meet SEEN commits -- and then we should mark them as
	 * SEEN as well.
	 */
	if (!commit_is_complete(commit))
		return 0;
	*it = commit;
	return 1;
}

static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
		const char *email, unsigned long timestamp, int tz,
		const char *message, void *cb_data)
{
	struct expire_reflog_cb *cb = cb_data;
	struct commit *old, *new;

	if (timestamp < cb->cmd->expire_total)
		goto prune;

	if (cb->cmd->rewrite)
		osha1 = cb->last_kept_sha1;

	old = new = NULL;
	if (cb->cmd->stalefix &&
	    (!keep_entry(&old, osha1) || !keep_entry(&new, nsha1)))
		goto prune;

	if (timestamp < cb->cmd->expire_unreachable) {
		if (!cb->ref_commit)
			goto prune;
		if (!old && !is_null_sha1(osha1))
			old = lookup_commit_reference_gently(osha1, 1);
		if (!new && !is_null_sha1(nsha1))
			new = lookup_commit_reference_gently(nsha1, 1);
		if ((old && !in_merge_bases(old, &cb->ref_commit, 1)) ||
		    (new && !in_merge_bases(new, &cb->ref_commit, 1)))
			goto prune;
	}

	if (cb->cmd->recno && --(cb->cmd->recno) == 0)
		goto prune;

	if (cb->newlog) {
		char sign = (tz < 0) ? '-' : '+';
		int zone = (tz < 0) ? (-tz) : tz;
		fprintf(cb->newlog, "%s %s %s %lu %c%04d\t%s",
			sha1_to_hex(osha1), sha1_to_hex(nsha1),
			email, timestamp, sign, zone,
			message);
		hashcpy(cb->last_kept_sha1, nsha1);
	}
	if (cb->cmd->verbose)
		printf("keep %s", message);
	return 0;
 prune:
	if (!cb->newlog || cb->cmd->verbose)
		printf("%sprune %s", cb->newlog ? "" : "would ", message);
	return 0;
}

static int expire_reflog(const char *ref, const unsigned char *sha1, int unused, void *cb_data)
{
	struct cmd_reflog_expire_cb *cmd = cb_data;
	struct expire_reflog_cb cb;
	struct ref_lock *lock;
	char *log_file, *newlog_path = NULL;
	int status = 0;

	memset(&cb, 0, sizeof(cb));

	/*
	 * we take the lock for the ref itself to prevent it from
	 * getting updated.
	 */
	lock = lock_any_ref_for_update(ref, sha1, 0);
	if (!lock)
		return error("cannot lock ref '%s'", ref);
	log_file = xstrdup(git_path("logs/%s", ref));
	if (!file_exists(log_file))
		goto finish;
	if (!cmd->dry_run) {
		newlog_path = xstrdup(git_path("logs/%s.lock", ref));
		cb.newlog = fopen(newlog_path, "w");
	}

	cb.ref_commit = lookup_commit_reference_gently(sha1, 1);
	cb.ref = ref;
	cb.cmd = cmd;
	for_each_reflog_ent(ref, expire_reflog_ent, &cb);
 finish:
	if (cb.newlog) {
		if (fclose(cb.newlog)) {
			status |= error("%s: %s", strerror(errno),
					newlog_path);
			unlink(newlog_path);
		} else if (cmd->updateref &&
			(write_in_full(lock->lock_fd,
				sha1_to_hex(cb.last_kept_sha1), 40) != 40 ||
			 write_in_full(lock->lock_fd, "\n", 1) != 1 ||
			 close_ref(lock) < 0)) {
			status |= error("Couldn't write %s",
				lock->lk->filename);
			unlink(newlog_path);
		} else if (rename(newlog_path, log_file)) {
			status |= error("cannot rename %s to %s",
					newlog_path, log_file);
			unlink(newlog_path);
		} else if (cmd->updateref && commit_ref(lock)) {
			status |= error("Couldn't set %s", lock->ref_name);
		} else {
			adjust_shared_perm(log_file);
		}
	}
	free(newlog_path);
	free(log_file);
	unlock_ref(lock);
	return status;
}

static int collect_reflog(const char *ref, const unsigned char *sha1, int unused, void *cb_data)
{
	struct collected_reflog *e;
	struct collect_reflog_cb *cb = cb_data;
	size_t namelen = strlen(ref);

	e = xmalloc(sizeof(*e) + namelen + 1);
	hashcpy(e->sha1, sha1);
	memcpy(e->reflog, ref, namelen + 1);
	ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
	cb->e[cb->nr++] = e;
	return 0;
}

static struct reflog_expire_cfg {
	struct reflog_expire_cfg *next;
	unsigned long expire_total;
	unsigned long expire_unreachable;
	size_t len;
	char pattern[FLEX_ARRAY];
} *reflog_expire_cfg, **reflog_expire_cfg_tail;

static struct reflog_expire_cfg *find_cfg_ent(const char *pattern, size_t len)
{
	struct reflog_expire_cfg *ent;

	if (!reflog_expire_cfg_tail)
		reflog_expire_cfg_tail = &reflog_expire_cfg;

	for (ent = reflog_expire_cfg; ent; ent = ent->next)
		if (ent->len == len &&
		    !memcmp(ent->pattern, pattern, len))
			return ent;

	ent = xcalloc(1, (sizeof(*ent) + len));
	memcpy(ent->pattern, pattern, len);
	ent->len = len;
	*reflog_expire_cfg_tail = ent;
	reflog_expire_cfg_tail = &(ent->next);
	return ent;
}

static int parse_expire_cfg_value(const char *var, const char *value, unsigned long *expire)
{
	if (!value)
		return config_error_nonbool(var);
	if (!strcmp(value, "never") || !strcmp(value, "false")) {
		*expire = 0;
		return 0;
	}
	*expire = approxidate(value);
	return 0;
}

/* expiry timer slot */
#define EXPIRE_TOTAL   01
#define EXPIRE_UNREACH 02

static int reflog_expire_config(const char *var, const char *value, void *cb)
{
	const char *lastdot = strrchr(var, '.');
	unsigned long expire;
	int slot;
	struct reflog_expire_cfg *ent;

	if (!lastdot || prefixcmp(var, "gc."))
		return git_default_config(var, value, cb);

	if (!strcmp(lastdot, ".reflogexpire")) {
		slot = EXPIRE_TOTAL;
		if (parse_expire_cfg_value(var, value, &expire))
			return -1;
	} else if (!strcmp(lastdot, ".reflogexpireunreachable")) {
		slot = EXPIRE_UNREACH;
		if (parse_expire_cfg_value(var, value, &expire))
			return -1;
	} else
		return git_default_config(var, value, cb);

	if (lastdot == var + 2) {
		switch (slot) {
		case EXPIRE_TOTAL:
			default_reflog_expire = expire;
			break;
		case EXPIRE_UNREACH:
			default_reflog_expire_unreachable = expire;
			break;
		}
		return 0;
	}

	ent = find_cfg_ent(var + 3, lastdot - (var+3));
	if (!ent)
		return -1;
	switch (slot) {
	case EXPIRE_TOTAL:
		ent->expire_total = expire;
		break;
	case EXPIRE_UNREACH:
		ent->expire_unreachable = expire;
		break;
	}
	return 0;
}

static void set_reflog_expiry_param(struct cmd_reflog_expire_cb *cb, int slot, const char *ref)
{
	struct reflog_expire_cfg *ent;

	if (slot == (EXPIRE_TOTAL|EXPIRE_UNREACH))
		return; /* both given explicitly -- nothing to tweak */

	for (ent = reflog_expire_cfg; ent; ent = ent->next) {
		if (!fnmatch(ent->pattern, ref, 0)) {
			if (!(slot & EXPIRE_TOTAL))
				cb->expire_total = ent->expire_total;
			if (!(slot & EXPIRE_UNREACH))
				cb->expire_unreachable = ent->expire_unreachable;
			return;
		}
	}

	/*
	 * If unconfigured, make stash never expire
	 */
	if (!strcmp(ref, "refs/stash")) {
		if (!(slot & EXPIRE_TOTAL))
			cb->expire_total = 0;
		if (!(slot & EXPIRE_UNREACH))
			cb->expire_unreachable = 0;
		return;
	}

	/* Nothing matched -- use the default value */
	if (!(slot & EXPIRE_TOTAL))
		cb->expire_total = default_reflog_expire;
	if (!(slot & EXPIRE_UNREACH))
		cb->expire_unreachable = default_reflog_expire_unreachable;
}

static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
{
	struct cmd_reflog_expire_cb cb;
	unsigned long now = time(NULL);
	int i, status, do_all;
	int explicit_expiry = 0;

	git_config(reflog_expire_config, NULL);

	save_commit_buffer = 0;
	do_all = status = 0;
	memset(&cb, 0, sizeof(cb));

	if (!default_reflog_expire_unreachable)
		default_reflog_expire_unreachable = now - 30 * 24 * 3600;
	if (!default_reflog_expire)
		default_reflog_expire = now - 90 * 24 * 3600;
	cb.expire_total = default_reflog_expire;
	cb.expire_unreachable = default_reflog_expire_unreachable;

	for (i = 1; i < argc; i++) {
		const char *arg = argv[i];
		if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
			cb.dry_run = 1;
		else if (!prefixcmp(arg, "--expire=")) {
			cb.expire_total = approxidate(arg + 9);
			explicit_expiry |= EXPIRE_TOTAL;
		}
		else if (!prefixcmp(arg, "--expire-unreachable=")) {
			cb.expire_unreachable = approxidate(arg + 21);
			explicit_expiry |= EXPIRE_UNREACH;
		}
		else if (!strcmp(arg, "--stale-fix"))
			cb.stalefix = 1;
		else if (!strcmp(arg, "--rewrite"))
			cb.rewrite = 1;
		else if (!strcmp(arg, "--updateref"))
			cb.updateref = 1;
		else if (!strcmp(arg, "--all"))
			do_all = 1;
		else if (!strcmp(arg, "--verbose"))
			cb.verbose = 1;
		else if (!strcmp(arg, "--")) {
			i++;
			break;
		}
		else if (arg[0] == '-')
			usage(reflog_expire_usage);
		else
			break;
	}

	/*
	 * We can trust the commits and objects reachable from refs
	 * even in older repository.  We cannot trust what's reachable
	 * from reflog if the repository was pruned with older git.
	 */
	if (cb.stalefix) {
		init_revisions(&cb.revs, prefix);
		if (cb.verbose)
			printf("Marking reachable objects...");
		mark_reachable_objects(&cb.revs, 0);
		if (cb.verbose)
			putchar('\n');
	}

	if (do_all) {
		struct collect_reflog_cb collected;
		int i;

		memset(&collected, 0, sizeof(collected));
		for_each_reflog(collect_reflog, &collected);
		for (i = 0; i < collected.nr; i++) {
			struct collected_reflog *e = collected.e[i];
			set_reflog_expiry_param(&cb, explicit_expiry, e->reflog);
			status |= expire_reflog(e->reflog, e->sha1, 0, &cb);
			free(e);
		}
		free(collected.e);
	}

	while (i < argc) {
		const char *ref = argv[i++];
		unsigned char sha1[20];
		if (!resolve_ref(ref, sha1, 1, NULL)) {
			status |= error("%s points nowhere!", ref);
			continue;
		}
		set_reflog_expiry_param(&cb, explicit_expiry, ref);
		status |= expire_reflog(ref, sha1, 0, &cb);
	}
	return status;
}

static int count_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
		const char *email, unsigned long timestamp, int tz,
		const char *message, void *cb_data)
{
	struct cmd_reflog_expire_cb *cb = cb_data;
	if (!cb->expire_total || timestamp < cb->expire_total)
		cb->recno++;
	return 0;
}

static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
{
	struct cmd_reflog_expire_cb cb;
	int i, status = 0;

	memset(&cb, 0, sizeof(cb));

	for (i = 1; i < argc; i++) {
		const char *arg = argv[i];
		if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
			cb.dry_run = 1;
		else if (!strcmp(arg, "--rewrite"))
			cb.rewrite = 1;
		else if (!strcmp(arg, "--updateref"))
			cb.updateref = 1;
		else if (!strcmp(arg, "--verbose"))
			cb.verbose = 1;
		else if (!strcmp(arg, "--")) {
			i++;
			break;
		}
		else if (arg[0] == '-')
			usage(reflog_delete_usage);
		else
			break;
	}

	if (argc - i < 1)
		return error("Nothing to delete?");

	for ( ; i < argc; i++) {
		const char *spec = strstr(argv[i], "@{");
		unsigned char sha1[20];
		char *ep, *ref;
		int recno;

		if (!spec) {
			status |= error("Not a reflog: %s", argv[i]);
			continue;
		}

		if (!dwim_log(argv[i], spec - argv[i], sha1, &ref)) {
			status |= error("no reflog for '%s'", argv[i]);
			continue;
		}

		recno = strtoul(spec + 2, &ep, 10);
		if (*ep == '}') {
			cb.recno = -recno;
			for_each_reflog_ent(ref, count_reflog_ent, &cb);
		} else {
			cb.expire_total = approxidate(spec + 2);
			for_each_reflog_ent(ref, count_reflog_ent, &cb);
			cb.expire_total = 0;
		}

		status |= expire_reflog(ref, sha1, 0, &cb);
		free(ref);
	}
	return status;
}

/*
 * main "reflog"
 */

static const char reflog_usage[] =
"git reflog (expire | ...)";

int cmd_reflog(int argc, const char **argv, const char *prefix)
{
	/* With no command, we default to showing it. */
	if (argc < 2 || *argv[1] == '-')
		return cmd_log_reflog(argc, argv, prefix);

	if (!strcmp(argv[1], "show"))
		return cmd_log_reflog(argc - 1, argv + 1, prefix);

	if (!strcmp(argv[1], "expire"))
		return cmd_reflog_expire(argc - 1, argv + 1, prefix);

	if (!strcmp(argv[1], "delete"))
		return cmd_reflog_delete(argc - 1, argv + 1, prefix);

	/* Not a recognized reflog command..*/
	usage(reflog_usage);
}
Commit	Line	Data
4264dc15 JH	1	#include "cache.h"
	2	#include "builtin.h"
	3	#include "commit.h"
	4	#include "refs.h"
	5	#include "dir.h"
8d8b9f62	6	#include "tree-walk.h"
1389d9dd JH	7	#include "diff.h"
	8	#include "revision.h"
	9	#include "reachable.h"
	10
	11	/*
	12	* reflog expire
	13	*/
	14
	15	static const char reflog_expire_usage[] =
1b1dd23f	16	"git reflog (show\|expire) [--verbose] [--dry-run] [--stale-fix] [--expire=<time>] [--expire-unreachable=<time>] [--all] <refs>...";
3c386aa3	17	static const char reflog_delete_usage[] =
1b1dd23f	18	"git reflog delete [--verbose] [--dry-run] [--rewrite] [--updateref] <refs>...";
4264dc15	19
4aec56d1 JH	20	static unsigned long default_reflog_expire;
	21	static unsigned long default_reflog_expire_unreachable;
	22
1389d9dd JH	23	struct cmd_reflog_expire_cb {
	24	struct rev_info revs;
	25	int dry_run;
	26	int stalefix;
2b81fab2	27	int rewrite;
55f10565	28	int updateref;
1389d9dd JH	29	int verbose;
	30	unsigned long expire_total;
	31	unsigned long expire_unreachable;
552cecc2	32	int recno;
1389d9dd JH	33	};
1389d9dd JH	34
4264dc15 JH	35	struct expire_reflog_cb {
	36	FILE *newlog;
	37	const char *ref;
	38	struct commit *ref_commit;
1389d9dd	39	struct cmd_reflog_expire_cb *cmd;
2b81fab2	40	unsigned char last_kept_sha1[20];
4264dc15 JH	41	};
4264dc15 JH	42
bda3a31c JH	43	struct collected_reflog {
	44	unsigned char sha1[20];
	45	char reflog[FLEX_ARRAY];
	46	};
	47	struct collect_reflog_cb {
	48	struct collected_reflog **e;
	49	int alloc;
	50	int nr;
	51	};
	52
cd1f9c36 JH	53	#define INCOMPLETE (1u<<10)
	54	#define STUDYING (1u<<11)
	55
8d8b9f62 JH	56	static int tree_is_complete(const unsigned char *sha1)
	57	{
	58	struct tree_desc desc;
cd1f9c36 JH	59	struct name_entry entry;
	60	int complete;
	61	struct tree *tree;
8d8b9f62	62
cd1f9c36 JH	63	tree = lookup_tree(sha1);
cd1f9c36 JH	64	if (!tree)
8d8b9f62	65	return 0;
cd1f9c36 JH	66	if (tree->object.flags & SEEN)
	67	return 1;
	68	if (tree->object.flags & INCOMPLETE)
	69	return 0;
	70
6fda5e51	71	if (!tree->buffer) {
21666f1a	72	enum object_type type;
6fda5e51 LT	73	unsigned long size;
6fda5e51 LT	74	void *data = read_sha1_file(sha1, &type, &size);
cd1f9c36 JH	75	if (!data) {
cd1f9c36 JH	76	tree->object.flags \|= INCOMPLETE;
8d8b9f62 JH	77	return 0;
8d8b9f62 JH	78	}
cd1f9c36	79	tree->buffer = data;
6fda5e51	80	tree->size = size;
8d8b9f62	81	}
6fda5e51	82	init_tree_desc(&desc, tree->buffer, tree->size);
cd1f9c36 JH	83	complete = 1;
	84	while (tree_entry(&desc, &entry)) {
	85	if (!has_sha1_file(entry.sha1) \|\|
	86	(S_ISDIR(entry.mode) && !tree_is_complete(entry.sha1))) {
	87	tree->object.flags \|= INCOMPLETE;
	88	complete = 0;
	89	}
	90	}
	91	free(tree->buffer);
	92	tree->buffer = NULL;
8d8b9f62	93
cd1f9c36 JH	94	if (complete)
	95	tree->object.flags \|= SEEN;
	96	return complete;
	97	}
1389d9dd JH	98
	99	static int commit_is_complete(struct commit *commit)
	100	{
	101	struct object_array study;
	102	struct object_array found;
	103	int is_incomplete = 0;
	104	int i;
	105
	106	/* early return */
	107	if (commit->object.flags & SEEN)
	108	return 1;
	109	if (commit->object.flags & INCOMPLETE)
	110	return 0;
	111	/*
	112	* Find all commits that are reachable and are not marked as
	113	* SEEN. Then make sure the trees and blobs contained are
	114	* complete. After that, mark these commits also as SEEN.
	115	* If some of the objects that are needed to complete this
	116	* commit are missing, mark this commit as INCOMPLETE.
	117	*/
	118	memset(&study, 0, sizeof(study));
	119	memset(&found, 0, sizeof(found));
	120	add_object_array(&commit->object, NULL, &study);
	121	add_object_array(&commit->object, NULL, &found);
	122	commit->object.flags \|= STUDYING;
	123	while (study.nr) {
	124	struct commit *c;
	125	struct commit_list *parent;
	126
	127	c = (struct commit *)study.objects[--study.nr].item;
	128	if (!c->object.parsed && !parse_object(c->object.sha1))
	129	c->object.flags \|= INCOMPLETE;
	130
	131	if (c->object.flags & INCOMPLETE) {
	132	is_incomplete = 1;
	133	break;
	134	}
	135	else if (c->object.flags & SEEN)
	136	continue;
	137	for (parent = c->parents; parent; parent = parent->next) {
	138	struct commit *p = parent->item;
	139	if (p->object.flags & STUDYING)
	140	continue;
	141	p->object.flags \|= STUDYING;
	142	add_object_array(&p->object, NULL, &study);
	143	add_object_array(&p->object, NULL, &found);
	144	}
	145	}
	146	if (!is_incomplete) {
cd1f9c36 JH	147	/*
cd1f9c36 JH	148	* make sure all commits in "found" array have all the
1389d9dd JH	149	* necessary objects.
1389d9dd JH	150	*/
cd1f9c36	151	for (i = 0; i < found.nr; i++) {
1389d9dd JH	152	struct commit *c =
1389d9dd JH	153	(struct commit *)found.objects[i].item;
cd1f9c36	154	if (!tree_is_complete(c->tree->object.sha1)) {
1389d9dd	155	is_incomplete = 1;
cd1f9c36 JH	156	c->object.flags \|= INCOMPLETE;
cd1f9c36 JH	157	}
1389d9dd JH	158	}
	159	if (!is_incomplete) {
	160	/* mark all found commits as complete, iow SEEN */
	161	for (i = 0; i < found.nr; i++)
	162	found.objects[i].item->flags \|= SEEN;
	163	}
	164	}
	165	/* clear flags from the objects we traversed */
	166	for (i = 0; i < found.nr; i++)
	167	found.objects[i].item->flags &= ~STUDYING;
	168	if (is_incomplete)
	169	commit->object.flags \|= INCOMPLETE;
cd1f9c36 JH	170	else {
	171	/*
	172	* If we come here, we have (1) traversed the ancestry chain
	173	* from the "commit" until we reach SEEN commits (which are
	174	* known to be complete), and (2) made sure that the commits
	175	* encountered during the above traversal refer to trees that
	176	* are complete. Which means that we know all the commits
	177	* we have seen during this process are complete.
	178	*/
	179	for (i = 0; i < found.nr; i++)
	180	found.objects[i].item->flags \|= SEEN;
	181	}
1389d9dd JH	182	/* free object arrays */
	183	free(study.objects);
	184	free(found.objects);
	185	return !is_incomplete;
	186	}
	187
4264dc15 JH	188	static int keep_entry(struct commit *it, unsigned char sha1)
4264dc15 JH	189	{
8d8b9f62 JH	190	struct commit *commit;
8d8b9f62 JH	191
4264dc15 JH	192	if (is_null_sha1(sha1))
4264dc15 JH	193	return 1;
8d8b9f62 JH	194	commit = lookup_commit_reference_gently(sha1, 1);
	195	if (!commit)
	196	return 0;
	197
1389d9dd JH	198	/*
	199	* Make sure everything in this commit exists.
	200	*
	201	* We have walked all the objects reachable from the refs
	202	* and cache earlier. The commits reachable by this commit
	203	* must meet SEEN commits -- and then we should mark them as
	204	* SEEN as well.
	205	*/
	206	if (!commit_is_complete(commit))
8d8b9f62 JH	207	return 0;
	208	*it = commit;
	209	return 1;
4264dc15 JH	210	}
	211
	212	static int expire_reflog_ent(unsigned char osha1, unsigned char nsha1,
883d60fa JS	213	const char *email, unsigned long timestamp, int tz,
883d60fa JS	214	const char message, void cb_data)
4264dc15 JH	215	{
4264dc15 JH	216	struct expire_reflog_cb *cb = cb_data;
4264dc15 JH	217	struct commit old, new;
4264dc15 JH	218
1389d9dd	219	if (timestamp < cb->cmd->expire_total)
4264dc15 JH	220	goto prune;
4264dc15 JH	221
2b81fab2 BC	222	if (cb->cmd->rewrite)
	223	osha1 = cb->last_kept_sha1;
	224
9bbaa6cc	225	old = new = NULL;
1389d9dd JH	226	if (cb->cmd->stalefix &&
1389d9dd JH	227	(!keep_entry(&old, osha1) \|\| !keep_entry(&new, nsha1)))
4264dc15 JH	228	goto prune;
4264dc15 JH	229
9bbaa6cc JH	230	if (timestamp < cb->cmd->expire_unreachable) {
	231	if (!cb->ref_commit)
	232	goto prune;
	233	if (!old && !is_null_sha1(osha1))
	234	old = lookup_commit_reference_gently(osha1, 1);
	235	if (!new && !is_null_sha1(nsha1))
	236	new = lookup_commit_reference_gently(nsha1, 1);
4a164d48 JH	237	if ((old && !in_merge_bases(old, &cb->ref_commit, 1)) \|\|
4a164d48 JH	238	(new && !in_merge_bases(new, &cb->ref_commit, 1)))
9bbaa6cc JH	239	goto prune;
9bbaa6cc JH	240	}
4264dc15	241
552cecc2 JS	242	if (cb->cmd->recno && --(cb->cmd->recno) == 0)
	243	goto prune;
	244
883d60fa JS	245	if (cb->newlog) {
	246	char sign = (tz < 0) ? '-' : '+';
	247	int zone = (tz < 0) ? (-tz) : tz;
	248	fprintf(cb->newlog, "%s %s %s %lu %c%04d\t%s",
	249	sha1_to_hex(osha1), sha1_to_hex(nsha1),
	250	email, timestamp, sign, zone,
	251	message);
2b81fab2	252	hashcpy(cb->last_kept_sha1, nsha1);
883d60fa	253	}
1389d9dd	254	if (cb->cmd->verbose)
883d60fa	255	printf("keep %s", message);
4264dc15 JH	256	return 0;
4264dc15 JH	257	prune:
1389d9dd	258	if (!cb->newlog \|\| cb->cmd->verbose)
883d60fa	259	printf("%sprune %s", cb->newlog ? "" : "would ", message);
4264dc15 JH	260	return 0;
	261	}
	262
4264dc15 JH	263	static int expire_reflog(const char ref, const unsigned char sha1, int unused, void *cb_data)
	264	{
	265	struct cmd_reflog_expire_cb *cmd = cb_data;
	266	struct expire_reflog_cb cb;
	267	struct ref_lock *lock;
9a13f0b7	268	char log_file, newlog_path = NULL;
4264dc15 JH	269	int status = 0;
4264dc15 JH	270
4264dc15	271	memset(&cb, 0, sizeof(cb));
3cb22b8e JH	272
	273	/*
	274	* we take the lock for the ref itself to prevent it from
4264dc15 JH	275	* getting updated.
4264dc15 JH	276	*/
68db31cc	277	lock = lock_any_ref_for_update(ref, sha1, 0);
4264dc15 JH	278	if (!lock)
4264dc15 JH	279	return error("cannot lock ref '%s'", ref);
9a13f0b7 NP	280	log_file = xstrdup(git_path("logs/%s", ref));
9a13f0b7 NP	281	if (!file_exists(log_file))
4264dc15 JH	282	goto finish;
	283	if (!cmd->dry_run) {
	284	newlog_path = xstrdup(git_path("logs/%s.lock", ref));
	285	cb.newlog = fopen(newlog_path, "w");
	286	}
	287
	288	cb.ref_commit = lookup_commit_reference_gently(sha1, 1);
4264dc15	289	cb.ref = ref;
1389d9dd	290	cb.cmd = cmd;
4264dc15 JH	291	for_each_reflog_ent(ref, expire_reflog_ent, &cb);
	292	finish:
	293	if (cb.newlog) {
4cd883d7	294	if (fclose(cb.newlog)) {
4264dc15 JH	295	status \|= error("%s: %s", strerror(errno),
4264dc15 JH	296	newlog_path);
4cd883d7	297	unlink(newlog_path);
55f10565 BC	298	} else if (cmd->updateref &&
	299	(write_in_full(lock->lock_fd,
	300	sha1_to_hex(cb.last_kept_sha1), 40) != 40 \|\|
	301	write_in_full(lock->lock_fd, "\n", 1) != 1 \|\|
	302	close_ref(lock) < 0)) {
	303	status \|= error("Couldn't write %s",
	304	lock->lk->filename);
	305	unlink(newlog_path);
4cd883d7	306	} else if (rename(newlog_path, log_file)) {
4264dc15	307	status \|= error("cannot rename %s to %s",
9a13f0b7	308	newlog_path, log_file);
4264dc15	309	unlink(newlog_path);
55f10565 BC	310	} else if (cmd->updateref && commit_ref(lock)) {
55f10565 BC	311	status \|= error("Couldn't set %s", lock->ref_name);
336d09da PH	312	} else {
336d09da PH	313	adjust_shared_perm(log_file);
4264dc15 JH	314	}
	315	}
	316	free(newlog_path);
9a13f0b7	317	free(log_file);
4264dc15 JH	318	unlock_ref(lock);
	319	return status;
	320	}
	321
bda3a31c JH	322	static int collect_reflog(const char ref, const unsigned char sha1, int unused, void *cb_data)
	323	{
	324	struct collected_reflog *e;
	325	struct collect_reflog_cb *cb = cb_data;
	326	size_t namelen = strlen(ref);
	327
	328	e = xmalloc(sizeof(*e) + namelen + 1);
	329	hashcpy(e->sha1, sha1);
	330	memcpy(e->reflog, ref, namelen + 1);
	331	ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
	332	cb->e[cb->nr++] = e;
	333	return 0;
	334	}
	335
3cb22b8e JH	336	static struct reflog_expire_cfg {
	337	struct reflog_expire_cfg *next;
	338	unsigned long expire_total;
	339	unsigned long expire_unreachable;
	340	size_t len;
	341	char pattern[FLEX_ARRAY];
	342	} reflog_expire_cfg, *reflog_expire_cfg_tail;
	343
	344	static struct reflog_expire_cfg find_cfg_ent(const char pattern, size_t len)
4aec56d1	345	{
3cb22b8e JH	346	struct reflog_expire_cfg *ent;
	347
	348	if (!reflog_expire_cfg_tail)
	349	reflog_expire_cfg_tail = &reflog_expire_cfg;
	350
	351	for (ent = reflog_expire_cfg; ent; ent = ent->next)
	352	if (ent->len == len &&
	353	!memcmp(ent->pattern, pattern, len))
	354	return ent;
	355
	356	ent = xcalloc(1, (sizeof(*ent) + len));
	357	memcpy(ent->pattern, pattern, len);
	358	ent->len = len;
	359	*reflog_expire_cfg_tail = ent;
	360	reflog_expire_cfg_tail = &(ent->next);
	361	return ent;
	362	}
	363
	364	static int parse_expire_cfg_value(const char var, const char value, unsigned long *expire)
	365	{
	366	if (!value)
	367	return config_error_nonbool(var);
	368	if (!strcmp(value, "never") \|\| !strcmp(value, "false")) {
	369	*expire = 0;
4f342b96 JH	370	return 0;
4f342b96 JH	371	}
3cb22b8e JH	372	*expire = approxidate(value);
	373	return 0;
	374	}
	375
	376	/* expiry timer slot */
	377	#define EXPIRE_TOTAL 01
	378	#define EXPIRE_UNREACH 02
	379
	380	static int reflog_expire_config(const char var, const char value, void *cb)
	381	{
	382	const char *lastdot = strrchr(var, '.');
	383	unsigned long expire;
	384	int slot;
	385	struct reflog_expire_cfg *ent;
	386
	387	if (!lastdot \|\| prefixcmp(var, "gc."))
	388	return git_default_config(var, value, cb);
	389
	390	if (!strcmp(lastdot, ".reflogexpire")) {
	391	slot = EXPIRE_TOTAL;
	392	if (parse_expire_cfg_value(var, value, &expire))
	393	return -1;
	394	} else if (!strcmp(lastdot, ".reflogexpireunreachable")) {
	395	slot = EXPIRE_UNREACH;
	396	if (parse_expire_cfg_value(var, value, &expire))
	397	return -1;
	398	} else
	399	return git_default_config(var, value, cb);
	400
	401	if (lastdot == var + 2) {
	402	switch (slot) {
	403	case EXPIRE_TOTAL:
	404	default_reflog_expire = expire;
	405	break;
	406	case EXPIRE_UNREACH:
	407	default_reflog_expire_unreachable = expire;
	408	break;
	409	}
4f342b96 JH	410	return 0;
4f342b96 JH	411	}
3cb22b8e JH	412
	413	ent = find_cfg_ent(var + 3, lastdot - (var+3));
	414	if (!ent)
	415	return -1;
	416	switch (slot) {
	417	case EXPIRE_TOTAL:
	418	ent->expire_total = expire;
	419	break;
	420	case EXPIRE_UNREACH:
	421	ent->expire_unreachable = expire;
	422	break;
	423	}
	424	return 0;
	425	}
	426
	427	static void set_reflog_expiry_param(struct cmd_reflog_expire_cb cb, int slot, const char ref)
	428	{
	429	struct reflog_expire_cfg *ent;
	430
	431	if (slot == (EXPIRE_TOTAL\|EXPIRE_UNREACH))
	432	return; /* both given explicitly -- nothing to tweak */
	433
	434	for (ent = reflog_expire_cfg; ent; ent = ent->next) {
	435	if (!fnmatch(ent->pattern, ref, 0)) {
	436	if (!(slot & EXPIRE_TOTAL))
	437	cb->expire_total = ent->expire_total;
	438	if (!(slot & EXPIRE_UNREACH))
	439	cb->expire_unreachable = ent->expire_unreachable;
	440	return;
	441	}
	442	}
	443
60bce2bb JH	444	/*
	445	* If unconfigured, make stash never expire
	446	*/
	447	if (!strcmp(ref, "refs/stash")) {
	448	if (!(slot & EXPIRE_TOTAL))
	449	cb->expire_total = 0;
	450	if (!(slot & EXPIRE_UNREACH))
	451	cb->expire_unreachable = 0;
	452	return;
	453	}
	454
3cb22b8e JH	455	/* Nothing matched -- use the default value */
	456	if (!(slot & EXPIRE_TOTAL))
	457	cb->expire_total = default_reflog_expire;
	458	if (!(slot & EXPIRE_UNREACH))
	459	cb->expire_unreachable = default_reflog_expire_unreachable;
4aec56d1 JH	460	}
4aec56d1 JH	461
4264dc15 JH	462	static int cmd_reflog_expire(int argc, const char *argv, const char prefix)
	463	{
	464	struct cmd_reflog_expire_cb cb;
	465	unsigned long now = time(NULL);
	466	int i, status, do_all;
3cb22b8e	467	int explicit_expiry = 0;
4264dc15	468
ef90d6d4	469	git_config(reflog_expire_config, NULL);
4aec56d1	470
4264dc15 JH	471	save_commit_buffer = 0;
	472	do_all = status = 0;
	473	memset(&cb, 0, sizeof(cb));
4aec56d1 JH	474
	475	if (!default_reflog_expire_unreachable)
	476	default_reflog_expire_unreachable = now - 30 * 24 * 3600;
	477	if (!default_reflog_expire)
	478	default_reflog_expire = now - 90 * 24 * 3600;
	479	cb.expire_total = default_reflog_expire;
	480	cb.expire_unreachable = default_reflog_expire_unreachable;
4264dc15 JH	481
	482	for (i = 1; i < argc; i++) {
	483	const char *arg = argv[i];
	484	if (!strcmp(arg, "--dry-run") \|\| !strcmp(arg, "-n"))
	485	cb.dry_run = 1;
3cb22b8e	486	else if (!prefixcmp(arg, "--expire=")) {
4264dc15	487	cb.expire_total = approxidate(arg + 9);
3cb22b8e JH	488	explicit_expiry \|= EXPIRE_TOTAL;
	489	}
	490	else if (!prefixcmp(arg, "--expire-unreachable=")) {
4264dc15	491	cb.expire_unreachable = approxidate(arg + 21);
3cb22b8e JH	492	explicit_expiry \|= EXPIRE_UNREACH;
3cb22b8e JH	493	}
1389d9dd JH	494	else if (!strcmp(arg, "--stale-fix"))
1389d9dd JH	495	cb.stalefix = 1;
2b81fab2 BC	496	else if (!strcmp(arg, "--rewrite"))
2b81fab2 BC	497	cb.rewrite = 1;
55f10565 BC	498	else if (!strcmp(arg, "--updateref"))
55f10565 BC	499	cb.updateref = 1;
4264dc15 JH	500	else if (!strcmp(arg, "--all"))
4264dc15 JH	501	do_all = 1;
1389d9dd JH	502	else if (!strcmp(arg, "--verbose"))
1389d9dd JH	503	cb.verbose = 1;
4264dc15 JH	504	else if (!strcmp(arg, "--")) {
	505	i++;
	506	break;
	507	}
	508	else if (arg[0] == '-')
	509	usage(reflog_expire_usage);
	510	else
	511	break;
	512	}
3cb22b8e JH	513
	514	/*
	515	* We can trust the commits and objects reachable from refs
	516	* even in older repository. We cannot trust what's reachable
	517	* from reflog if the repository was pruned with older git.
	518	*/
1389d9dd JH	519	if (cb.stalefix) {
	520	init_revisions(&cb.revs, prefix);
	521	if (cb.verbose)
	522	printf("Marking reachable objects...");
	523	mark_reachable_objects(&cb.revs, 0);
	524	if (cb.verbose)
	525	putchar('\n');
	526	}
	527
bda3a31c JH	528	if (do_all) {
	529	struct collect_reflog_cb collected;
	530	int i;
	531
	532	memset(&collected, 0, sizeof(collected));
	533	for_each_reflog(collect_reflog, &collected);
	534	for (i = 0; i < collected.nr; i++) {
	535	struct collected_reflog *e = collected.e[i];
3cb22b8e	536	set_reflog_expiry_param(&cb, explicit_expiry, e->reflog);
bda3a31c JH	537	status \|= expire_reflog(e->reflog, e->sha1, 0, &cb);
	538	free(e);
	539	}
	540	free(collected.e);
	541	}
	542
4264dc15 JH	543	while (i < argc) {
	544	const char *ref = argv[i++];
	545	unsigned char sha1[20];
	546	if (!resolve_ref(ref, sha1, 1, NULL)) {
	547	status \|= error("%s points nowhere!", ref);
	548	continue;
	549	}
3cb22b8e	550	set_reflog_expiry_param(&cb, explicit_expiry, ref);
4264dc15 JH	551	status \|= expire_reflog(ref, sha1, 0, &cb);
	552	}
	553	return status;
	554	}
	555
552cecc2 JS	556	static int count_reflog_ent(unsigned char osha1, unsigned char nsha1,
	557	const char *email, unsigned long timestamp, int tz,
	558	const char message, void cb_data)
	559	{
	560	struct cmd_reflog_expire_cb *cb = cb_data;
	561	if (!cb->expire_total \|\| timestamp < cb->expire_total)
	562	cb->recno++;
	563	return 0;
	564	}
	565
	566	static int cmd_reflog_delete(int argc, const char *argv, const char prefix)
	567	{
	568	struct cmd_reflog_expire_cb cb;
	569	int i, status = 0;
	570
552cecc2 JS	571	memset(&cb, 0, sizeof(cb));
	572
	573	for (i = 1; i < argc; i++) {
3c386aa3 BC	574	const char *arg = argv[i];
	575	if (!strcmp(arg, "--dry-run") \|\| !strcmp(arg, "-n"))
	576	cb.dry_run = 1;
2b81fab2 BC	577	else if (!strcmp(arg, "--rewrite"))
2b81fab2 BC	578	cb.rewrite = 1;
55f10565 BC	579	else if (!strcmp(arg, "--updateref"))
55f10565 BC	580	cb.updateref = 1;
3c386aa3 BC	581	else if (!strcmp(arg, "--verbose"))
	582	cb.verbose = 1;
	583	else if (!strcmp(arg, "--")) {
	584	i++;
	585	break;
	586	}
	587	else if (arg[0] == '-')
	588	usage(reflog_delete_usage);
	589	else
	590	break;
	591	}
	592
	593	if (argc - i < 1)
	594	return error("Nothing to delete?");
	595
	596	for ( ; i < argc; i++) {
552cecc2 JS	597	const char *spec = strstr(argv[i], "@{");
	598	unsigned char sha1[20];
	599	char ep, ref;
	600	int recno;
	601
	602	if (!spec) {
cb97cc9f	603	status \|= error("Not a reflog: %s", argv[i]);
552cecc2 JS	604	continue;
	605	}
	606
55beff4f JH	607	if (!dwim_log(argv[i], spec - argv[i], sha1, &ref)) {
55beff4f JH	608	status \|= error("no reflog for '%s'", argv[i]);
552cecc2 JS	609	continue;
	610	}
	611
	612	recno = strtoul(spec + 2, &ep, 10);
	613	if (*ep == '}') {
	614	cb.recno = -recno;
	615	for_each_reflog_ent(ref, count_reflog_ent, &cb);
	616	} else {
	617	cb.expire_total = approxidate(spec + 2);
	618	for_each_reflog_ent(ref, count_reflog_ent, &cb);
	619	cb.expire_total = 0;
	620	}
	621
	622	status \|= expire_reflog(ref, sha1, 0, &cb);
	623	free(ref);
	624	}
	625	return status;
	626	}
	627
1389d9dd JH	628	/*
	629	* main "reflog"
	630	*/
	631
4264dc15	632	static const char reflog_usage[] =
1b1dd23f	633	"git reflog (expire \| ...)";
4264dc15 JH	634
	635	int cmd_reflog(int argc, const char *argv, const char prefix)
	636	{
cf39f54e LT	637	/* With no command, we default to showing it. */
	638	if (argc < 2 \|\| *argv[1] == '-')
	639	return cmd_log_reflog(argc, argv, prefix);
	640
	641	if (!strcmp(argv[1], "show"))
	642	return cmd_log_reflog(argc - 1, argv + 1, prefix);
	643
	644	if (!strcmp(argv[1], "expire"))
4264dc15	645	return cmd_reflog_expire(argc - 1, argv + 1, prefix);
cf39f54e	646
552cecc2 JS	647	if (!strcmp(argv[1], "delete"))
	648	return cmd_reflog_delete(argc - 1, argv + 1, prefix);
	649
cf39f54e LT	650	/* Not a recognized reflog command..*/
cf39f54e LT	651	usage(reflog_usage);
4264dc15	652	}