thodg/libgit2

diff --git a/include/git2/refspec.h b/include/git2/refspec.h
index 9e84aad..1100e90 100644
--- a/include/git2/refspec.h
+++ b/include/git2/refspec.h
@@ -20,14 +20,6 @@
 GIT_BEGIN_DECL
 
 /**
- * Parse a refspec string and create a refspec object
- *
- * @param refspec pointer to the refspec structure to be used
- * @param str the refspec as a string
- */
-GIT_EXTERN(int) git_refspec_parse(git_refspec *refspec, const char *str);
-
-/**
  * Get the source specifier
  *
  * @param refspec the refspec
diff --git a/include/git2/remote.h b/include/git2/remote.h
index a3913af..c015289 100644
--- a/include/git2/remote.h
+++ b/include/git2/remote.h
@@ -304,6 +304,30 @@ struct git_remote_callbacks {
  */
 GIT_EXTERN(void) git_remote_set_callbacks(git_remote *remote, git_remote_callbacks *callbacks);
 
+enum {
+	GIT_REMOTE_DOWNLOAD_TAGS_UNSET,
+	GIT_REMOTE_DOWNLOAD_TAGS_NONE,
+	GIT_REMOTE_DOWNLOAD_TAGS_AUTO,
+	GIT_REMOTE_DOWNLOAD_TAGS_ALL
+};
+
+/**
+ * Retrieve the tag auto-follow setting
+ *
+ * @param remote the remote to query
+ * @return the auto-follow setting
+ */
+GIT_EXTERN(int) git_remote_autotag(git_remote *remote);
+
+/**
+ * Set the tag auto-follow setting
+ *
+ * @param remote the remote to configure
+ * @param value a GIT_REMOTE_DOWNLOAD_TAGS value
+ */
+GIT_EXTERN(void) git_remote_set_autotag(git_remote *remote, int value);
+
+
 /** @} */
 GIT_END_DECL
 #endif
diff --git a/src/fetch.c b/src/fetch.c
index 98e1f0b..f9cc8aa 100644
--- a/src/fetch.c
+++ b/src/fetch.c
@@ -21,7 +21,7 @@
 
 struct filter_payload {
 	git_remote *remote;
-	const git_refspec *spec;
+	const git_refspec *spec, *tagspec;
 	git_odb *odb;
 	int found_head;
 };
@@ -29,18 +29,21 @@ struct filter_payload {
 static int filter_ref__cb(git_remote_head *head, void *payload)
 {
 	struct filter_payload *p = payload;
+	int match = 0;
 
-	if (!p->found_head && strcmp(head->name, GIT_HEAD_FILE) == 0) {
+	if (!git_reference_is_valid_name(head->name))
+		return 0;
+
+	if (!p->found_head && strcmp(head->name, GIT_HEAD_FILE) == 0)
 		p->found_head = 1;
-	} else {
-		/* If it doesn't match the refpec, we don't want it */
-		if (!git_refspec_src_matches(p->spec, head->name))
-			return 0;
+	else if (git_refspec_src_matches(p->spec, head->name))
+			match = 1;
+	else if (p->remote->download_tags == GIT_REMOTE_DOWNLOAD_TAGS_ALL &&
+		 git_refspec_src_matches(p->tagspec, head->name))
+			match = 1;
 
-		/* Don't even try to ask for the annotation target */
-		if (!git__suffixcmp(head->name, "^{}"))
-			return 0;
-	}
+	if (!match)
+		return 0;
 
 	/* If we have the object, mark it so we don't ask for it */
 	if (git_odb_exists(p->odb, &head->oid))
@@ -54,8 +57,11 @@ static int filter_ref__cb(git_remote_head *head, void *payload)
 static int filter_wants(git_remote *remote)
 {
 	struct filter_payload p;
+	git_refspec tagspec;
 
 	git_vector_clear(&remote->refs);
+	if (git_refspec__parse(&tagspec, GIT_REFSPEC_TAGS, true) < 0)
+		return -1;
 
 	/*
 	 * The fetch refspec can be NULL, and what this means is that the
@@ -64,6 +70,7 @@ static int filter_wants(git_remote *remote)
 	 * HEAD, which will be stored in FETCH_HEAD after the fetch.
 	 */
 	p.spec = git_remote_fetchspec(remote);
+	p.tagspec = &tagspec;
 	p.found_head = 0;
 	p.remote = remote;
 
diff --git a/src/pkt.c b/src/pkt.c
index ad0149d..91f9b65 100644
--- a/src/pkt.c
+++ b/src/pkt.c
@@ -354,6 +354,9 @@ static int buffer_want_with_caps(git_remote_head *head, git_transport_caps *caps
 	if (caps->multi_ack)
 		git_buf_puts(&str, GIT_CAP_MULTI_ACK " ");
 
+	if (caps->include_tag)
+		git_buf_puts(&str, GIT_CAP_INCLUDE_TAG " ");
+
 	if (git_buf_oom(&str))
 		return -1;
 
diff --git a/src/protocol.c b/src/protocol.c
index 4526c85..8f673cd 100644
--- a/src/protocol.c
+++ b/src/protocol.c
@@ -80,6 +80,12 @@ int git_protocol_detect_caps(git_pkt_ref *pkt, git_transport_caps *caps)
 			continue;
 		}
 
+		if(!git__prefixcmp(ptr, GIT_CAP_INCLUDE_TAG)) {
+			caps->common = caps->include_tag = 1;
+			ptr += strlen(GIT_CAP_INCLUDE_TAG);
+			continue;
+		}
+
 		/* Keep side-band check after side-band-64k */
 		if(!git__prefixcmp(ptr, GIT_CAP_SIDE_BAND_64K)) {
 			caps->common = caps->side_band_64k = 1;
diff --git a/src/refs.c b/src/refs.c
index 693870a..903accc 100644
--- a/src/refs.c
+++ b/src/refs.c
@@ -1199,6 +1199,7 @@ int git_reference_create_symbolic(
 {
 	char normalized[GIT_REFNAME_MAX];
 	git_reference *ref = NULL;
+	int error;
 
 	if (git_reference__normalize_name_lax(
 		normalized,
@@ -1206,8 +1207,8 @@ int git_reference_create_symbolic(
 		name) < 0)
 			return -1;
 
-	if (reference_can_write(repo, normalized, NULL, force) < 0)
-		return -1;
+	if ((error = reference_can_write(repo, normalized, NULL, force)) < 0)
+		return error;
 
 	if (reference_alloc(&ref, repo, normalized) < 0)
 		return -1;
@@ -1236,6 +1237,7 @@ int git_reference_create_oid(
 	const git_oid *id,
 	int force)
 {
+	int error;
 	git_reference *ref = NULL;
 	char normalized[GIT_REFNAME_MAX];
 
@@ -1245,8 +1247,8 @@ int git_reference_create_oid(
 		name) < 0)
 			return -1;
 
-	if (reference_can_write(repo, normalized, NULL, force) < 0)
-		return -1;
+	if ((error = reference_can_write(repo, normalized, NULL, force)) < 0)
+		return error;
 
 	if (reference_alloc(&ref, repo, name) < 0)
 		return -1;
diff --git a/src/refspec.c b/src/refspec.c
index 1265c56..cd3a528 100644
--- a/src/refspec.c
+++ b/src/refspec.c
@@ -125,35 +125,10 @@ int git_refspec__parse(git_refspec *refspec, const char *input, bool is_fetch)
 	return -1;
 }
 
-int git_refspec_parse(git_refspec *refspec, const char *str)
+void git_refspec__free(git_refspec *refspec)
 {
-	char *delim;
-
-	memset(refspec, 0x0, sizeof(git_refspec));
-
-	if (*str == '+') {
-		refspec->force = 1;
-		str++;
-	}
-
-	delim = strchr(str, ':');
-	if (delim == NULL) {
-		refspec->src = git__strdup(str);
-		GITERR_CHECK_ALLOC(refspec->src);
-		return 0;
-	}
-
-	refspec->src = git__strndup(str, delim - str);
-	GITERR_CHECK_ALLOC(refspec->src);
-
-	refspec->dst = git__strdup(delim + 1);
-	if (refspec->dst == NULL) {
-		git__free(refspec->src);
-		refspec->src = NULL;
-		return -1;
-	}
-
-	return 0;
+	git__free(refspec->src);
+	git__free(refspec->dst);
 }
 
 const char *git_refspec_src(const git_refspec *refspec)
diff --git a/src/refspec.h b/src/refspec.h
index 2f46b3e..a5df458 100644
--- a/src/refspec.h
+++ b/src/refspec.h
@@ -19,12 +19,16 @@ struct git_refspec {
 		matching :1;
 };
 
+#define GIT_REFSPEC_TAGS "refs/tags/*:refs/tags/*"
+
 int git_refspec_parse(struct git_refspec *refspec, const char *str);
 int git_refspec__parse(
 	struct git_refspec *refspec,
 	const char *str,
 	bool is_fetch);
 
+void git_refspec__free(git_refspec *refspec);
+
 /**
  * Transform a reference to its target following the refspec's rules,
  * and writes the results into a git_buf.
diff --git a/src/remote.c b/src/remote.c
index 7bc631d..fd78164 100644
--- a/src/remote.c
+++ b/src/remote.c
@@ -18,41 +18,42 @@
 
 #include <regex.h>
 
-static int refspec_parse(git_refspec *refspec, const char *str)
+static int parse_remote_refspec(git_config *cfg, git_refspec *refspec, const char *var, bool is_fetch)
 {
-	char *delim;
-
-	memset(refspec, 0x0, sizeof(git_refspec));
-
-	if (*str == '+') {
-		refspec->force = 1;
-		str++;
-	}
-
-	delim = strchr(str, ':');
-	if (delim == NULL) {
-		giterr_set(GITERR_NET, "Invalid refspec, missing ':'");
-		return -1;
-	}
-
-	refspec->src = git__strndup(str, delim - str);
-	GITERR_CHECK_ALLOC(refspec->src);
+	int error;
+	const char *val;
 
-	refspec->dst = git__strdup(delim + 1);
-	GITERR_CHECK_ALLOC(refspec->dst);
+	if ((error = git_config_get_string(&val, cfg, var)) < 0)
+		return error;
 
-	return 0;
+	return git_refspec__parse(refspec, val, is_fetch);
 }
 
-static int parse_remote_refspec(git_config *cfg, git_refspec *refspec, const char *var)
+static int download_tags_value(git_remote *remote, git_config *cfg)
 {
-	int error;
 	const char *val;
+	git_buf buf = GIT_BUF_INIT;
+	int error;
 
-	if ((error = git_config_get_string(&val, cfg, var)) < 0)
-		return error;
+	if (remote->download_tags != GIT_REMOTE_DOWNLOAD_TAGS_UNSET)
+		return 0;
 
-	return refspec_parse(refspec, val);
+	/* This is the default, let's see if we need to change it */
+	remote->download_tags = GIT_REMOTE_DOWNLOAD_TAGS_AUTO;
+	if (git_buf_printf(&buf, "remote.%s.tagopt", remote->name) < 0)
+		return -1;
+
+	error = git_config_get_string(&val, cfg, git_buf_cstr(&buf));
+	git_buf_free(&buf);
+	if (!error && !strcmp(val, "--no-tags"))
+		remote->download_tags = GIT_REMOTE_DOWNLOAD_TAGS_NONE;
+	else if (!error && !strcmp(val, "--tags"))
+		remote->download_tags = GIT_REMOTE_DOWNLOAD_TAGS_ALL;
+
+	if (error == GIT_ENOTFOUND)
+		error = 0;
+
+	return error;
 }
 
 int git_remote_new(git_remote **out, git_repository *repo, const char *name, const char *url, const char *fetch)
@@ -81,7 +82,7 @@ int git_remote_new(git_remote **out, git_repository *repo, const char *name, con
 	}
 
 	if (fetch != NULL) {
-		if (refspec_parse(&remote->fetch, fetch) < 0)
+		if (git_refspec__parse(&remote->fetch, fetch, true) < 0)
 			goto on_error;
 	}
 
@@ -157,7 +158,7 @@ int git_remote_load(git_remote **out, git_repository *repo, const char *name)
 		goto cleanup;
 	}
 
-	error = parse_remote_refspec(config, &remote->fetch, git_buf_cstr(&buf));
+	error = parse_remote_refspec(config, &remote->fetch, git_buf_cstr(&buf), true);
 	if (error == GIT_ENOTFOUND)
 		error = 0;
 
@@ -172,7 +173,7 @@ int git_remote_load(git_remote **out, git_repository *repo, const char *name)
 		goto cleanup;
 	}
 
-	error = parse_remote_refspec(config, &remote->push, git_buf_cstr(&buf));
+	error = parse_remote_refspec(config, &remote->push, git_buf_cstr(&buf), false);
 	if (error == GIT_ENOTFOUND)
 		error = 0;
 
@@ -181,6 +182,9 @@ int git_remote_load(git_remote **out, git_repository *repo, const char *name)
 		goto cleanup;
 	}
 
+	if (download_tags_value(remote, config) < 0)
+		goto cleanup;
+
 	*out = remote;
 
 cleanup:
@@ -317,11 +321,10 @@ int git_remote_set_fetchspec(git_remote *remote, const char *spec)
 
 	assert(remote && spec);
 
-	if (refspec_parse(&refspec, spec) < 0)
+	if (git_refspec__parse(&refspec, spec, true) < 0)
 		return -1;
 
-	git__free(remote->fetch.src);
-	git__free(remote->fetch.dst);
+	git_refspec__free(&remote->fetch);
 	remote->fetch.src = refspec.src;
 	remote->fetch.dst = refspec.dst;
 
@@ -340,11 +343,10 @@ int git_remote_set_pushspec(git_remote *remote, const char *spec)
 
 	assert(remote && spec);
 
-	if (refspec_parse(&refspec, spec) < 0)
+	if (git_refspec__parse(&refspec, spec, false) < 0)
 		return -1;
 
-	git__free(remote->push.src);
-	git__free(remote->push.dst);
+	git_refspec__free(&remote->push);
 	remote->push.src = refspec.src;
 	remote->push.dst = refspec.dst;
 
@@ -445,25 +447,35 @@ int git_remote_download(git_remote *remote, git_off_t *bytes, git_indexer_stats 
 
 int git_remote_update_tips(git_remote *remote)
 {
-	int error = 0;
+	int error = 0, autotag;
 	unsigned int i = 0;
 	git_buf refname = GIT_BUF_INIT;
 	git_oid old;
+	git_pkt *pkt;
+	git_odb *odb;
 	git_vector *refs;
 	git_remote_head *head;
 	git_reference *ref;
 	struct git_refspec *spec;
+	git_refspec tagspec;
 
 	assert(remote);
 
-	refs = &remote->refs;
+	refs = &remote->transport->refs;
 	spec = &remote->fetch;
 
 	if (refs->length == 0)
 		return 0;
 
+	if (git_repository_odb(&odb, remote->repo) < 0)
+		return -1;
+
+	if (git_refspec__parse(&tagspec, GIT_REFSPEC_TAGS, true) < 0)
+		return -1;
+
 	/* HEAD is only allowed to be the first in the list */
-	head = refs->contents[0];
+	pkt = refs->contents[0];
+	head = &((git_pkt_ref *)pkt)->head;
 	if (!strcmp(head->name, GIT_HEAD_FILE)) {
 		if (git_reference_create_oid(&ref, remote->repo, GIT_FETCH_HEAD_FILE, &head->oid, 1) < 0)
 			return -1;
@@ -473,10 +485,38 @@ int git_remote_update_tips(git_remote *remote)
 	}
 
 	for (; i < refs->length; ++i) {
-		head = refs->contents[i];
+		autotag = 0;
+		git_pkt *pkt = refs->contents[i];
 
-		if (git_refspec_transform_r(&refname, spec, head->name) < 0)
-			goto on_error;
+		if (pkt->type == GIT_PKT_REF)
+			head = &((git_pkt_ref *)pkt)->head;
+		else
+			continue;
+
+		/* Ignore malformed ref names (which also saves us from tag^{} */
+		if (!git_reference_is_valid_name(head->name))
+			continue;
+
+		if (git_refspec_src_matches(spec, head->name)) {
+			if (git_refspec_transform_r(&refname, spec, head->name) < 0)
+				goto on_error;
+		} else if (remote->download_tags != GIT_REMOTE_DOWNLOAD_TAGS_NONE) {
+
+			if (remote->download_tags != GIT_REMOTE_DOWNLOAD_TAGS_ALL)
+				autotag = 1;
+
+			if (!git_refspec_src_matches(&tagspec, head->name))
+				continue;
+
+			git_buf_clear(&refname);
+			if (git_buf_puts(&refname, head->name) < 0)
+				goto on_error;
+		} else {
+			continue;
+		}
+
+		if (autotag && !git_odb_exists(odb, &head->oid))
+			continue;
 
 		error = git_reference_name_to_oid(&old, remote->repo, refname.ptr);
 		if (error < 0 && error != GIT_ENOTFOUND)
@@ -488,7 +528,9 @@ int git_remote_update_tips(git_remote *remote)
 		if (!git_oid_cmp(&old, &head->oid))
 			continue;
 
-		if (git_reference_create_oid(&ref, remote->repo, refname.ptr, &head->oid, 1) < 0)
+		/* In autotag mode, don't overwrite any locally-existing tags */
+		error = git_reference_create_oid(&ref, remote->repo, refname.ptr, &head->oid, !autotag);
+		if (error < 0 && error != GIT_EEXISTS)
 			goto on_error;
 
 		git_reference_free(ref);
@@ -499,10 +541,12 @@ int git_remote_update_tips(git_remote *remote)
 		}
 	}
 
+	git_refspec__free(&tagspec);
 	git_buf_free(&refname);
 	return 0;
 
 on_error:
+	git_refspec__free(&tagspec);
 	git_buf_free(&refname);
 	return -1;
 
@@ -536,10 +580,8 @@ void git_remote_free(git_remote *remote)
 
 	git_vector_free(&remote->refs);
 
-	git__free(remote->fetch.src);
-	git__free(remote->fetch.dst);
-	git__free(remote->push.src);
-	git__free(remote->push.dst);
+	git_refspec__free(&remote->fetch);
+	git_refspec__free(&remote->push);
 	git__free(remote->url);
 	git__free(remote->pushurl);
 	git__free(remote->name);
@@ -655,3 +697,13 @@ void git_remote_set_callbacks(git_remote *remote, git_remote_callbacks *callback
 		remote->transport->cb_data = remote->callbacks.data;
 	}
 }
+
+int git_remote_autotag(git_remote *remote)
+{
+	return remote->download_tags;
+}
+
+void git_remote_set_autotag(git_remote *remote, int value)
+{
+	remote->download_tags = value;
+}
diff --git a/src/remote.h b/src/remote.h
index 67933a3..b8bb2c5 100644
--- a/src/remote.h
+++ b/src/remote.h
@@ -24,7 +24,8 @@ struct git_remote {
 	git_repository *repo;
 	git_remote_callbacks callbacks;
 	unsigned int need_pack:1,
-		check_cert;
+		download_tags:2, /* There are four possible values */
+		check_cert:1;
 };
 
 const char* git_remote__urlfordirection(struct git_remote *remote, int direction);
diff --git a/src/transport.h b/src/transport.h
index ff3a58d..9c91afd 100644
--- a/src/transport.h
+++ b/src/transport.h
@@ -23,13 +23,15 @@
 #define GIT_CAP_MULTI_ACK "multi_ack"
 #define GIT_CAP_SIDE_BAND "side-band"
 #define GIT_CAP_SIDE_BAND_64K "side-band-64k"
+#define GIT_CAP_INCLUDE_TAG "include-tag"
 
 typedef struct git_transport_caps {
 	int common:1,
 		ofs_delta:1,
 		multi_ack: 1,
 		side_band:1,
-		side_band_64k:1;
+		side_band_64k:1,
+		include_tag:1;
 } git_transport_caps;
 
 #ifdef GIT_SSL
diff --git a/tests-clar/network/refspecs.c b/tests-clar/network/refspecs.c
index bfe0af4..3b12817 100644
--- a/tests-clar/network/refspecs.c
+++ b/tests-clar/network/refspecs.c
@@ -8,6 +8,7 @@ static void assert_refspec(unsigned int direction, const char *input, bool is_ex
 	int error;
 
 	error = git_refspec__parse(&refspec, input, direction == GIT_DIR_FETCH);
+	git_refspec__free(&refspec);
 
 	if (is_expected_to_be_valid)
 		cl_assert_equal_i(0, error);
diff --git a/tests-clar/refs/create.c b/tests-clar/refs/create.c
index af5b203..bf234bc 100644
--- a/tests-clar/refs/create.c
+++ b/tests-clar/refs/create.c
@@ -147,3 +147,18 @@ void test_refs_create__oid_unknown(void)
 	/* Ensure the reference can't be looked-up... */
 	cl_git_fail(git_reference_lookup(&looked_up_ref, g_repo, new_head));
 }
+
+void test_refs_create__propagate_eexists(void)
+{
+	int error;
+	git_oid oid;
+	git_reference *ref;
+
+	/* Make sure it works for oid and for symbolic both */
+	git_oid_fromstr(&oid, current_master_tip);
+	error = git_reference_create_oid(&ref, g_repo, current_head_target, &oid, false);
+	cl_assert(error == GIT_EEXISTS);
+
+	error = git_reference_create_symbolic(&ref, g_repo, "HEAD", current_head_target, false);
+	cl_assert(error == GIT_EEXISTS);
+}