1 files changed, 444 insertions, 44 deletions

diff --git a/ref-filter.c b/ref-filter.c
index 4991cd4f7a..fae9f4b8ed 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -1,14 +1,15 @@
 #include "git-compat-util.h"
-#include "alloc.h"
 #include "environment.h"
 #include "gettext.h"
+#include "config.h"
 #include "gpg-interface.h"
 #include "hex.h"
 #include "parse-options.h"
+#include "run-command.h"
 #include "refs.h"
 #include "wildmatch.h"
 #include "object-name.h"
-#include "object-store.h"
+#include "object-store-ll.h"
 #include "oid-array.h"
 #include "repository.h"
 #include "commit.h"
@@ -146,10 +147,12 @@ enum atom_type {
 	ATOM_TAGGERDATE,
 	ATOM_CREATOR,
 	ATOM_CREATORDATE,
+	ATOM_DESCRIBE,
 	ATOM_SUBJECT,
 	ATOM_BODY,
 	ATOM_TRAILERS,
 	ATOM_CONTENTS,
+	ATOM_SIGNATURE,
 	ATOM_RAW,
 	ATOM_UPSTREAM,
 	ATOM_PUSH,
@@ -215,6 +218,11 @@ static struct used_atom {
 		struct email_option {
 			enum { EO_RAW, EO_TRIM, EO_LOCALPART } option;
 		} email_option;
+		struct {
+			enum { S_BARE, S_GRADE, S_SIGNER, S_KEY,
+			       S_FINGERPRINT, S_PRI_KEY_FP, S_TRUST_LEVEL } option;
+		} signature;
+		const char **describe_args;
 		struct refname_atom refname;
 		char *head;
 	} u;
@@ -251,6 +259,110 @@ static int err_bad_arg(struct strbuf *sb, const char *name, const char *arg)
 	return -1;
 }
 
+/*
+ * Parse option of name "candidate" in the option string "to_parse" of
+ * the form
+ *
+ *	"candidate1[=val1],candidate2[=val2],candidate3[=val3],..."
+ *
+ * The remaining part of "to_parse" is stored in "end" (if we are
+ * parsing the last candidate, then this is NULL) and the value of
+ * the candidate is stored in "valuestart" and its length in "valuelen",
+ * that is the portion after "=". Since it is possible for a "candidate"
+ * to not have a value, in such cases, "valuestart" is set to point to
+ * NULL and "valuelen" to 0.
+ *
+ * The function returns 1 on success. It returns 0 if we don't find
+ * "candidate" in "to_parse" or we find "candidate" but it is followed
+ * by more chars (for example, "candidatefoo"), that is, we don't find
+ * an exact match.
+ *
+ * This function only does the above for one "candidate" at a time. So
+ * it has to be called each time trying to parse a "candidate" in the
+ * option string "to_parse".
+ */
+static int match_atom_arg_value(const char *to_parse, const char *candidate,
+				const char **end, const char **valuestart,
+				size_t *valuelen)
+{
+	const char *atom;
+
+	if (!skip_prefix(to_parse, candidate, &atom))
+		return 0; /* definitely not "candidate" */
+
+	if (*atom == '=') {
+		/* we just saw "candidate=" */
+		*valuestart = atom + 1;
+		atom = strchrnul(*valuestart, ',');
+		*valuelen = atom - *valuestart;
+	} else if (*atom != ',' && *atom != '\0') {
+		/* key begins with "candidate" but has more chars */
+		return 0;
+	} else {
+		/* just "candidate" without "=val" */
+		*valuestart = NULL;
+		*valuelen = 0;
+	}
+
+	/* atom points at either the ',' or NUL after this key[=val] */
+	if (*atom == ',')
+		atom++;
+	else if (*atom)
+		BUG("Why is *atom not NULL yet?");
+
+	*end = atom;
+	return 1;
+}
+
+/*
+ * Parse boolean option of name "candidate" in the option list "to_parse"
+ * of the form
+ *
+ *	"candidate1[=bool1],candidate2[=bool2],candidate3[=bool3],..."
+ *
+ * The remaining part of "to_parse" is stored in "end" (if we are parsing
+ * the last candidate, then this is NULL) and the value (if given) is
+ * parsed and stored in "val", so "val" always points to either 0 or 1.
+ * If the value is not given, then "val" is set to point to 1.
+ *
+ * The boolean value is parsed using "git_parse_maybe_bool()", so the
+ * accepted values are
+ *
+ *	to set true  - "1", "yes", "true"
+ *	to set false - "0", "no", "false"
+ *
+ * This function returns 1 on success. It returns 0 when we don't find
+ * an exact match for "candidate" or when the boolean value given is
+ * not valid.
+ */
+static int match_atom_bool_arg(const char *to_parse, const char *candidate,
+				const char **end, int *val)
+{
+	const char *argval;
+	char *strval;
+	size_t arglen;
+	int v;
+
+	if (!match_atom_arg_value(to_parse, candidate, end, &argval, &arglen))
+		return 0;
+
+	if (!argval) {
+		*val = 1;
+		return 1;
+	}
+
+	strval = xstrndup(argval, arglen);
+	v = git_parse_maybe_bool(strval);
+	free(strval);
+
+	if (v == -1)
+		return 0;
+
+	*val = v;
+
+	return 1;
+}
+
 static int color_atom_parser(struct ref_format *format, struct used_atom *atom,
 			     const char *color_value, struct strbuf *err)
 {
@@ -407,6 +519,36 @@ static int subject_atom_parser(struct ref_format *format UNUSED,
 	return 0;
 }
 
+static int parse_signature_option(const char *arg)
+{
+	if (!arg)
+		return S_BARE;
+	else if (!strcmp(arg, "signer"))
+		return S_SIGNER;
+	else if (!strcmp(arg, "grade"))
+		return S_GRADE;
+	else if (!strcmp(arg, "key"))
+		return S_KEY;
+	else if (!strcmp(arg, "fingerprint"))
+		return S_FINGERPRINT;
+	else if (!strcmp(arg, "primarykeyfingerprint"))
+		return S_PRI_KEY_FP;
+	else if (!strcmp(arg, "trustlevel"))
+		return S_TRUST_LEVEL;
+	return -1;
+}
+
+static int signature_atom_parser(struct ref_format *format UNUSED,
+				 struct used_atom *atom,
+				 const char *arg, struct strbuf *err)
+{
+	int opt = parse_signature_option(arg);
+	if (opt < 0)
+		return err_bad_arg(err, "signature", arg);
+	atom->u.signature.option = opt;
+	return 0;
+}
+
 static int trailers_atom_parser(struct ref_format *format UNUSED,
 				struct used_atom *atom,
 				const char *arg, struct strbuf *err)
@@ -441,9 +583,10 @@ static int contents_atom_parser(struct ref_format *format, struct used_atom *ato
 		atom->u.contents.option = C_BARE;
 	else if (!strcmp(arg, "body"))
 		atom->u.contents.option = C_BODY;
-	else if (!strcmp(arg, "size"))
+	else if (!strcmp(arg, "size")) {
+		atom->type = FIELD_ULONG;
 		atom->u.contents.option = C_LENGTH;
-	else if (!strcmp(arg, "signature"))
+	} else if (!strcmp(arg, "signature"))
 		atom->u.contents.option = C_SIG;
 	else if (!strcmp(arg, "subject"))
 		atom->u.contents.option = C_SUB;
@@ -462,15 +605,97 @@ static int contents_atom_parser(struct ref_format *format, struct used_atom *ato
 	return 0;
 }
 
+static int describe_atom_option_parser(struct strvec *args, const char **arg,
+				       struct strbuf *err)
+{
+	const char *argval;
+	size_t arglen = 0;
+	int optval = 0;
+
+	if (match_atom_bool_arg(*arg, "tags", arg, &optval)) {
+		if (!optval)
+			strvec_push(args, "--no-tags");
+		else
+			strvec_push(args, "--tags");
+		return 1;
+	}
+
+	if (match_atom_arg_value(*arg, "abbrev", arg, &argval, &arglen)) {
+		char *endptr;
+
+		if (!arglen)
+			return strbuf_addf_ret(err, -1,
+					       _("argument expected for %s"),
+					       "describe:abbrev");
+		if (strtol(argval, &endptr, 10) < 0)
+			return strbuf_addf_ret(err, -1,
+					       _("positive value expected %s=%s"),
+					       "describe:abbrev", argval);
+		if (endptr - argval != arglen)
+			return strbuf_addf_ret(err, -1,
+					       _("cannot fully parse %s=%s"),
+					       "describe:abbrev", argval);
+
+		strvec_pushf(args, "--abbrev=%.*s", (int)arglen, argval);
+		return 1;
+	}
+
+	if (match_atom_arg_value(*arg, "match", arg, &argval, &arglen)) {
+		if (!arglen)
+			return strbuf_addf_ret(err, -1,
+					       _("value expected %s="),
+					       "describe:match");
+
+		strvec_pushf(args, "--match=%.*s", (int)arglen, argval);
+		return 1;
+	}
+
+	if (match_atom_arg_value(*arg, "exclude", arg, &argval, &arglen)) {
+		if (!arglen)
+			return strbuf_addf_ret(err, -1,
+					       _("value expected %s="),
+					       "describe:exclude");
+
+		strvec_pushf(args, "--exclude=%.*s", (int)arglen, argval);
+		return 1;
+	}
+
+	return 0;
+}
+
+static int describe_atom_parser(struct ref_format *format UNUSED,
+				struct used_atom *atom,
+				const char *arg, struct strbuf *err)
+{
+	struct strvec args = STRVEC_INIT;
+
+	for (;;) {
+		int found = 0;
+		const char *bad_arg = arg;
+
+		if (!arg || !*arg)
+			break;
+
+		found = describe_atom_option_parser(&args, &arg, err);
+		if (found < 0)
+			return found;
+		if (!found)
+			return err_bad_arg(err, "describe", bad_arg);
+	}
+	atom->u.describe_args = strvec_detach(&args);
+	return 0;
+}
+
 static int raw_atom_parser(struct ref_format *format UNUSED,
 			   struct used_atom *atom,
 			   const char *arg, struct strbuf *err)
 {
 	if (!arg)
 		atom->u.raw_data.option = RAW_BARE;
-	else if (!strcmp(arg, "size"))
+	else if (!strcmp(arg, "size")) {
+		atom->type = FIELD_ULONG;
 		atom->u.raw_data.option = RAW_LENGTH;
-	else
+	} else
 		return err_bad_arg(err, "raw", arg);
 	return 0;
 }
@@ -597,7 +822,7 @@ static int if_atom_parser(struct ref_format *format UNUSED,
 	return 0;
 }
 
-static int rest_atom_parser(struct ref_format *format,
+static int rest_atom_parser(struct ref_format *format UNUSED,
 			    struct used_atom *atom UNUSED,
 			    const char *arg, struct strbuf *err)
 {
@@ -606,7 +831,8 @@ static int rest_atom_parser(struct ref_format *format,
 	return 0;
 }
 
-static int ahead_behind_atom_parser(struct ref_format *format, struct used_atom *atom,
+static int ahead_behind_atom_parser(struct ref_format *format,
+				    struct used_atom *atom UNUSED,
 				    const char *arg, struct strbuf *err)
 {
 	struct string_list_item *item;
@@ -664,10 +890,12 @@ static struct {
 	[ATOM_TAGGERDATE] = { "taggerdate", SOURCE_OBJ, FIELD_TIME },
 	[ATOM_CREATOR] = { "creator", SOURCE_OBJ },
 	[ATOM_CREATORDATE] = { "creatordate", SOURCE_OBJ, FIELD_TIME },
+	[ATOM_DESCRIBE] = { "describe", SOURCE_OBJ, FIELD_STR, describe_atom_parser },
 	[ATOM_SUBJECT] = { "subject", SOURCE_OBJ, FIELD_STR, subject_atom_parser },
 	[ATOM_BODY] = { "body", SOURCE_OBJ, FIELD_STR, body_atom_parser },
 	[ATOM_TRAILERS] = { "trailers", SOURCE_OBJ, FIELD_STR, trailers_atom_parser },
 	[ATOM_CONTENTS] = { "contents", SOURCE_OBJ, FIELD_STR, contents_atom_parser },
+	[ATOM_SIGNATURE] = { "signature", SOURCE_OBJ, FIELD_STR, signature_atom_parser },
 	[ATOM_RAW] = { "raw", SOURCE_OBJ, FIELD_STR, raw_atom_parser },
 	[ATOM_UPSTREAM] = { "upstream", SOURCE_NONE, FIELD_STR, remote_ref_atom_parser },
 	[ATOM_PUSH] = { "push", SOURCE_NONE, FIELD_STR, remote_ref_atom_parser },
@@ -1405,6 +1633,92 @@ static void grab_person(const char *who, struct atom_value *val, int deref, void
 	}
 }
 
+static void grab_signature(struct atom_value *val, int deref, struct object *obj)
+{
+	int i;
+	struct commit *commit = (struct commit *) obj;
+	struct signature_check sigc = { 0 };
+	int signature_checked = 0;
+
+	for (i = 0; i < used_atom_cnt; i++) {
+		struct used_atom *atom = &used_atom[i];
+		const char *name = atom->name;
+		struct atom_value *v = &val[i];
+		int opt;
+
+		if (!!deref != (*name == '*'))
+			continue;
+		if (deref)
+			name++;
+
+		if (!skip_prefix(name, "signature", &name) ||
+		    (*name && *name != ':'))
+			continue;
+		if (!*name)
+			name = NULL;
+		else
+			name++;
+
+		opt = parse_signature_option(name);
+		if (opt < 0)
+			continue;
+
+		if (!signature_checked) {
+			check_commit_signature(commit, &sigc);
+			signature_checked = 1;
+		}
+
+		switch (opt) {
+		case S_BARE:
+			v->s = xstrdup(sigc.output ? sigc.output: "");
+			break;
+		case S_SIGNER:
+			v->s = xstrdup(sigc.signer ? sigc.signer : "");
+			break;
+		case S_GRADE:
+			switch (sigc.result) {
+			case 'G':
+				switch (sigc.trust_level) {
+				case TRUST_UNDEFINED:
+				case TRUST_NEVER:
+					v->s = xstrfmt("%c", (char)'U');
+					break;
+				default:
+					v->s = xstrfmt("%c", (char)'G');
+					break;
+				}
+				break;
+			case 'B':
+			case 'E':
+			case 'N':
+			case 'X':
+			case 'Y':
+			case 'R':
+				v->s = xstrfmt("%c", (char)sigc.result);
+				break;
+			}
+			break;
+		case S_KEY:
+			v->s = xstrdup(sigc.key ? sigc.key : "");
+			break;
+		case S_FINGERPRINT:
+			v->s = xstrdup(sigc.fingerprint ?
+				       sigc.fingerprint : "");
+			break;
+		case S_PRI_KEY_FP:
+			v->s = xstrdup(sigc.primary_key_fingerprint ?
+				       sigc.primary_key_fingerprint : "");
+			break;
+		case S_TRUST_LEVEL:
+			v->s = xstrdup(gpg_trust_level_to_str(sigc.trust_level));
+			break;
+		}
+	}
+
+	if (signature_checked)
+		signature_check_clear(&sigc);
+}
+
 static void find_subpos(const char *buf,
 			const char **sub, size_t *sublen,
 			const char **body, size_t *bodylen,
@@ -1483,6 +1797,44 @@ static void append_lines(struct strbuf *out, const char *buf, unsigned long size
 	}
 }
 
+static void grab_describe_values(struct atom_value *val, int deref,
+				 struct object *obj)
+{
+	struct commit *commit = (struct commit *)obj;
+	int i;
+
+	for (i = 0; i < used_atom_cnt; i++) {
+		struct used_atom *atom = &used_atom[i];
+		enum atom_type type = atom->atom_type;
+		const char *name = atom->name;
+		struct atom_value *v = &val[i];
+
+		struct child_process cmd = CHILD_PROCESS_INIT;
+		struct strbuf out = STRBUF_INIT;
+		struct strbuf err = STRBUF_INIT;
+
+		if (type != ATOM_DESCRIBE)
+			continue;
+
+		if (!!deref != (*name == '*'))
+			continue;
+
+		cmd.git_cmd = 1;
+		strvec_push(&cmd.args, "describe");
+		strvec_pushv(&cmd.args, atom->u.describe_args);
+		strvec_push(&cmd.args, oid_to_hex(&commit->object.oid));
+		if (pipe_command(&cmd, NULL, 0, &out, 0, &err, 0) < 0) {
+			error(_("failed to run 'describe'"));
+			v->s = xstrdup("");
+			continue;
+		}
+		strbuf_rtrim(&out);
+		v->s = strbuf_detach(&out, NULL);
+
+		strbuf_release(&err);
+	}
+}
+
 /* See grab_values */
 static void grab_sub_body_contents(struct atom_value *val, int deref, struct expand_data *data)
 {
@@ -1509,7 +1861,8 @@ static void grab_sub_body_contents(struct atom_value *val, int deref, struct exp
 				v->s = xmemdupz(buf, buf_size);
 				v->s_size = buf_size;
 			} else if (atom->u.raw_data.option == RAW_LENGTH) {
-				v->s = xstrfmt("%"PRIuMAX, (uintmax_t)buf_size);
+				v->value = buf_size;
+				v->s = xstrfmt("%"PRIuMAX, v->value);
 			}
 			continue;
 		}
@@ -1535,9 +1888,10 @@ static void grab_sub_body_contents(struct atom_value *val, int deref, struct exp
 			v->s = strbuf_detach(&sb, NULL);
 		} else if (atom->u.contents.option == C_BODY_DEP)
 			v->s = xmemdupz(bodypos, bodylen);
-		else if (atom->u.contents.option == C_LENGTH)
-			v->s = xstrfmt("%"PRIuMAX, (uintmax_t)strlen(subpos));
-		else if (atom->u.contents.option == C_BODY)
+		else if (atom->u.contents.option == C_LENGTH) {
+			v->value = strlen(subpos);
+			v->s = xstrfmt("%"PRIuMAX, v->value);
+		} else if (atom->u.contents.option == C_BODY)
 			v->s = xmemdupz(bodypos, nonsiglen);
 		else if (atom->u.contents.option == C_SIG)
 			v->s = xmemdupz(sigpos, siglen);
@@ -1592,12 +1946,15 @@ static void grab_values(struct atom_value *val, int deref, struct object *obj, s
 		grab_tag_values(val, deref, obj);
 		grab_sub_body_contents(val, deref, data);
 		grab_person("tagger", val, deref, buf);
+		grab_describe_values(val, deref, obj);
 		break;
 	case OBJ_COMMIT:
 		grab_commit_values(val, deref, obj);
 		grab_sub_body_contents(val, deref, data);
 		grab_person("author", val, deref, buf);
 		grab_person("committer", val, deref, buf);
+		grab_signature(val, deref, obj);
+		grab_describe_values(val, deref, obj);
 		break;
 	case OBJ_TREE:
 		/* grab_tree_values(val, deref, obj, buf, sz); */
@@ -1914,6 +2271,7 @@ static int populate_value(struct ref_array_item *ref, struct strbuf *err)
 
 		v->s_size = ATOM_SIZE_UNSPECIFIED;
 		v->handler = append_atom;
+		v->value = 0;
 		v->atom = atom;
 
 		if (*name == '*') {
@@ -2104,12 +2462,12 @@ static int get_ref_atom_value(struct ref_array_item *ref, int atom,
  * matches a pattern "refs/heads/mas") or a wildcard (e.g. the same ref
  * matches "refs/heads/mas*", too).
  */
-static int match_pattern(const struct ref_filter *filter, const char *refname)
+static int match_pattern(const char **patterns, const char *refname,
+			 int ignore_case)
 {
-	const char **patterns = filter->name_patterns;
 	unsigned flags = 0;
 
-	if (filter->ignore_case)
+	if (ignore_case)
 		flags |= WM_CASEFOLD;
 
 	/*
@@ -2134,13 +2492,13 @@ static int match_pattern(const struct ref_filter *filter, const char *refname)
  * matches a pattern "refs/heads/" but not "refs/heads/m") or a
  * wildcard (e.g. the same ref matches "refs/heads/m*", too).
  */
-static int match_name_as_path(const struct ref_filter *filter, const char *refname)
+static int match_name_as_path(const char **pattern, const char *refname,
+			      int ignore_case)
 {
-	const char **pattern = filter->name_patterns;
 	int namelen = strlen(refname);
 	unsigned flags = WM_PATHNAME;
 
-	if (filter->ignore_case)
+	if (ignore_case)
 		flags |= WM_CASEFOLD;
 
 	for (; *pattern; pattern++) {
@@ -2165,8 +2523,20 @@ static int filter_pattern_match(struct ref_filter *filter, const char *refname)
 	if (!*filter->name_patterns)
 		return 1; /* No pattern always matches */
 	if (filter->match_as_path)
-		return match_name_as_path(filter, refname);
-	return match_pattern(filter, refname);
+		return match_name_as_path(filter->name_patterns, refname,
+					  filter->ignore_case);
+	return match_pattern(filter->name_patterns, refname,
+			     filter->ignore_case);
+}
+
+static int filter_exclude_match(struct ref_filter *filter, const char *refname)
+{
+	if (!filter->exclude.nr)
+		return 0;
+	if (filter->match_as_path)
+		return match_name_as_path(filter->exclude.v, refname,
+					  filter->ignore_case);
+	return match_pattern(filter->exclude.v, refname, filter->ignore_case);
 }
 
 /*
@@ -2198,43 +2568,53 @@ static int for_each_fullref_in_pattern(struct ref_filter *filter,
 
 	if (!filter->name_patterns[0]) {
 		/* no patterns; we have to look at everything */
-		return for_each_fullref_in("", cb, cb_data);
+		return refs_for_each_fullref_in(get_main_ref_store(the_repository),
+						 "", filter->exclude.v, cb, cb_data);
 	}
 
 	return refs_for_each_fullref_in_prefixes(get_main_ref_store(the_repository),
 						 NULL, filter->name_patterns,
+						 filter->exclude.v,
 						 cb, cb_data);
 }
 
 /*
  * Given a ref (oid, refname), check if the ref belongs to the array
  * of oids. If the given ref is a tag, check if the given tag points
- * at one of the oids in the given oid array.
+ * at one of the oids in the given oid array. Returns non-zero if a
+ * match is found.
+ *
  * NEEDSWORK:
- * 1. Only a single level of indirection is obtained, we might want to
- * change this to account for multiple levels (e.g. annotated tags
- * pointing to annotated tags pointing to a commit.)
- * 2. As the refs are cached we might know what refname peels to without
+ * As the refs are cached we might know what refname peels to without
  * the need to parse the object via parse_object(). peel_ref() might be a
  * more efficient alternative to obtain the pointee.
  */
-static const struct object_id *match_points_at(struct oid_array *points_at,
-					       const struct object_id *oid,
-					       const char *refname)
+static int match_points_at(struct oid_array *points_at,
+			   const struct object_id *oid,
+			   const char *refname)
 {
-	const struct object_id *tagged_oid = NULL;
 	struct object *obj;
 
 	if (oid_array_lookup(points_at, oid) >= 0)
-		return oid;
-	obj = parse_object(the_repository, oid);
+		return 1;
+	obj = parse_object_with_flags(the_repository, oid,
+				      PARSE_OBJECT_SKIP_HASH_CHECK);
+	while (obj && obj->type == OBJ_TAG) {
+		struct tag *tag = (struct tag *)obj;
+
+		if (parse_tag(tag) < 0) {
+			obj = NULL;
+			break;
+		}
+
+		if (oid_array_lookup(points_at, get_tagged_oid(tag)) >= 0)
+			return 1;
+
+		obj = tag->tagged;
+	}
 	if (!obj)
 		die(_("malformed object at '%s'"), refname);
-	if (obj->type == OBJ_TAG)
-		tagged_oid = get_tagged_oid((struct tag *)obj);
-	if (tagged_oid && oid_array_lookup(points_at, tagged_oid) >= 0)
-		return tagged_oid;
-	return NULL;
+	return 0;
 }
 
 /*
@@ -2336,6 +2716,9 @@ static int ref_filter_handler(const char *refname, const struct object_id *oid,
 	if (!filter_pattern_match(filter, refname))
 		return 0;
 
+	if (filter_exclude_match(filter, refname))
+		return 0;
+
 	if (filter->points_at.nr && !match_points_at(&filter->points_at, oid, refname))
 		return 0;
 
@@ -2418,13 +2801,13 @@ void ref_array_clear(struct ref_array *array)
 #define EXCLUDE_REACHED 0
 #define INCLUDE_REACHED 1
 static void reach_filter(struct ref_array *array,
-			 struct commit_list *check_reachable,
+			 struct commit_list **check_reachable,
 			 int include_reached)
 {
 	int i, old_nr;
 	struct commit **to_clear;
 
-	if (!check_reachable)
+	if (!*check_reachable)
 		return;
 
 	CALLOC_ARRAY(to_clear, array->nr);
@@ -2434,7 +2817,7 @@ static void reach_filter(struct ref_array *array,
 	}
 
 	tips_reachable_from_bases(the_repository,
-				  check_reachable,
+				  *check_reachable,
 				  to_clear, array->nr,
 				  UNINTERESTING);
 
@@ -2455,8 +2838,8 @@ static void reach_filter(struct ref_array *array,
 
 	clear_commit_marks_many(old_nr, to_clear, ALL_REV_FLAGS);
 
-	while (check_reachable) {
-		struct commit *merge_commit = pop_commit(&check_reachable);
+	while (*check_reachable) {
+		struct commit *merge_commit = pop_commit(check_reachable);
 		clear_commit_marks(merge_commit, ALL_REV_FLAGS);
 	}
 
@@ -2553,8 +2936,8 @@ int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int
 	clear_contains_cache(&ref_cbdata.no_contains_cache);
 
 	/*  Filters that need revision walking */
-	reach_filter(array, filter->reachable_from, INCLUDE_REACHED);
-	reach_filter(array, filter->unreachable_from, EXCLUDE_REACHED);
+	reach_filter(array, &filter->reachable_from, INCLUDE_REACHED);
+	reach_filter(array, &filter->unreachable_from, EXCLUDE_REACHED);
 
 	save_commit_buffer = save_commit_buffer_orig;
 	return ret;
@@ -2866,3 +3249,20 @@ int parse_opt_merge_filter(const struct option *opt, const char *arg, int unset)
 
 	return 0;
 }
+
+void ref_filter_init(struct ref_filter *filter)
+{
+	struct ref_filter blank = REF_FILTER_INIT;
+	memcpy(filter, &blank, sizeof(blank));
+}
+
+void ref_filter_clear(struct ref_filter *filter)
+{
+	strvec_clear(&filter->exclude);
+	oid_array_clear(&filter->points_at);
+	free_commit_list(filter->with_commit);
+	free_commit_list(filter->no_commit);
+	free_commit_list(filter->reachable_from);
+	free_commit_list(filter->unreachable_from);
+	ref_filter_init(filter);
+}