5 files changed, 290 insertions, 36 deletions

diff --git a/src/libgit2/transports/local.c b/src/libgit2/transports/local.c
index 4d86f1713..64c21afbd 100644
--- a/src/libgit2/transports/local.c
+++ b/src/libgit2/transports/local.c
@@ -295,15 +295,13 @@ static int local_ls(const git_remote_head ***out, size_t *size, git_transport *t
 static int local_negotiate_fetch(
 	git_transport *transport,
 	git_repository *repo,
-	const git_remote_head * const *refs,
-	size_t count)
+	const git_fetch_negotiation *wants)
 {
 	transport_local *t = (transport_local*)transport;
 	git_remote_head *rhead;
 	unsigned int i;
 
-	GIT_UNUSED(refs);
-	GIT_UNUSED(count);
+	GIT_UNUSED(wants);
 
 	/* Fill in the loids */
 	git_vector_foreach(&t->refs, i, rhead) {
@@ -322,6 +320,16 @@ static int local_negotiate_fetch(
 	return 0;
 }
 
+static int local_shallow_roots(
+	git_oidarray *out,
+	git_transport *transport)
+{
+	GIT_UNUSED(out);
+	GIT_UNUSED(transport);
+
+	return 0;
+}
+
 static int local_push_update_remote_ref(
 	git_repository *remote_repo,
 	const char *lref,
@@ -747,6 +755,7 @@ int git_transport_local(git_transport **out, git_remote *owner, void *param)
 	t->parent.oid_type = local_oid_type;
 #endif
 	t->parent.negotiate_fetch = local_negotiate_fetch;
+	t->parent.shallow_roots = local_shallow_roots;
 	t->parent.download_pack = local_download_pack;
 	t->parent.push = local_push;
 	t->parent.close = local_close;
diff --git a/src/libgit2/transports/smart.c b/src/libgit2/transports/smart.c
index c3a764bd3..a56524bff 100644
--- a/src/libgit2/transports/smart.c
+++ b/src/libgit2/transports/smart.c
@@ -416,6 +416,8 @@ static void git_smart__free(git_transport *transport)
 
 	git_remote_connect_options_dispose(&t->connect_opts);
 
+	git_array_dispose(t->shallow_roots);
+
 	git__free(t->caps.object_format);
 	git__free(t->caps.agent);
 	git__free(t);
@@ -490,6 +492,7 @@ int git_transport_smart(git_transport **out, git_remote *owner, void *param)
 	t->parent.close = git_smart__close;
 	t->parent.free = git_smart__free;
 	t->parent.negotiate_fetch = git_smart__negotiate_fetch;
+	t->parent.shallow_roots = git_smart__shallow_roots;
 	t->parent.download_pack = git_smart__download_pack;
 	t->parent.push = git_smart__push;
 	t->parent.ls = git_smart__ls;
diff --git a/src/libgit2/transports/smart.h b/src/libgit2/transports/smart.h
index d71160d8e..34e27ea8e 100644
--- a/src/libgit2/transports/smart.h
+++ b/src/libgit2/transports/smart.h
@@ -14,6 +14,7 @@
 #include "netops.h"
 #include "push.h"
 #include "str.h"
+#include "oidarray.h"
 #include "git2/sys/transport.h"
 
 #define GIT_SIDE_BAND_DATA     1
@@ -32,6 +33,7 @@
 #define GIT_CAP_SYMREF "symref"
 #define GIT_CAP_WANT_TIP_SHA1 "allow-tip-sha1-in-want"
 #define GIT_CAP_WANT_REACHABLE_SHA1 "allow-reachable-sha1-in-want"
+#define GIT_CAP_SHALLOW "shallow"
 #define GIT_CAP_OBJECT_FORMAT "object-format="
 #define GIT_CAP_AGENT "agent="
 
@@ -50,7 +52,9 @@ typedef enum {
 	GIT_PKT_PROGRESS,
 	GIT_PKT_OK,
 	GIT_PKT_NG,
-	GIT_PKT_UNPACK
+	GIT_PKT_UNPACK,
+	GIT_PKT_SHALLOW,
+	GIT_PKT_UNSHALLOW
 } git_pkt_type;
 
 /* Used for multi_ack and multi_ack_detailed */
@@ -122,6 +126,11 @@ typedef struct {
 	int unpack_ok;
 } git_pkt_unpack;
 
+typedef struct {
+	git_pkt_type type;
+	git_oid oid;
+} git_pkt_shallow;
+
 typedef struct transport_smart_caps {
 	unsigned int common:1,
 	             ofs_delta:1,
@@ -134,7 +143,8 @@ typedef struct transport_smart_caps {
 	             report_status:1,
 	             thin_pack:1,
 	             want_tip_sha1:1,
-	             want_reachable_sha1:1;
+	             want_reachable_sha1:1,
+	             shallow:1;
 	char *object_format;
 	char *agent;
 } transport_smart_caps;
@@ -153,6 +163,7 @@ typedef struct {
 	git_vector refs;
 	git_vector heads;
 	git_vector common;
+	git_array_oid_t shallow_roots;
 	git_atomic32 cancelled;
 	packetsize_cb packetsize_cb;
 	void *packetsize_payload;
@@ -171,8 +182,9 @@ int git_smart__push(git_transport *transport, git_push *push);
 int git_smart__negotiate_fetch(
 	git_transport *transport,
 	git_repository *repo,
-	const git_remote_head * const *refs,
-	size_t count);
+	const git_fetch_negotiation *wants);
+
+int git_smart__shallow_roots(git_oidarray *out, git_transport *transport);
 
 int git_smart__download_pack(
 	git_transport *transport,
@@ -195,7 +207,7 @@ int git_pkt_parse_line(git_pkt **head, const char **endptr, const char *line, si
 int git_pkt_buffer_flush(git_str *buf);
 int git_pkt_send_flush(GIT_SOCKET s);
 int git_pkt_buffer_done(git_str *buf);
-int git_pkt_buffer_wants(const git_remote_head * const *refs, size_t count, transport_smart_caps *caps, git_str *buf);
+int git_pkt_buffer_wants(const git_fetch_negotiation *wants, transport_smart_caps *caps, git_str *buf);
 int git_pkt_buffer_have(git_oid *oid, git_str *buf);
 void git_pkt_free(git_pkt *pkt);
 
diff --git a/src/libgit2/transports/smart_pkt.c b/src/libgit2/transports/smart_pkt.c
index 5fce42175..9127ad5fe 100644
--- a/src/libgit2/transports/smart_pkt.c
+++ b/src/libgit2/transports/smart_pkt.c
@@ -44,9 +44,16 @@ static int flush_pkt(git_pkt **out)
 }
 
 /* the rest of the line will be useful for multi_ack and multi_ack_detailed */
-static int ack_pkt(git_pkt **out, const char *line, size_t len)
+static int ack_pkt(
+	git_pkt **out,
+	const char *line,
+	size_t len,
+	git_pkt_parse_data *data)
 {
 	git_pkt_ack *pkt;
+	size_t oid_hexsize = git_oid_hexsize(data->oid_type);
+
+	GIT_ASSERT(data && data->oid_type);
 
 	pkt = git__calloc(1, sizeof(git_pkt_ack));
 	GIT_ERROR_CHECK_ALLOC(pkt);
@@ -57,11 +64,11 @@ static int ack_pkt(git_pkt **out, const char *line, size_t len)
 	line += 4;
 	len -= 4;
 
-	if (len < GIT_OID_SHA1_HEXSIZE ||
-	    git_oid__fromstr(&pkt->oid, line, GIT_OID_SHA1) < 0)
+	if (len < oid_hexsize ||
+	    git_oid__fromstr(&pkt->oid, line, data->oid_type) < 0)
 		goto out_err;
-	line += GIT_OID_SHA1_HEXSIZE;
-	len -= GIT_OID_SHA1_HEXSIZE;
+	line += oid_hexsize;
+	len -= oid_hexsize;
 
 	if (len && line[0] == ' ') {
 		line++;
@@ -436,6 +443,84 @@ static int unpack_pkt(git_pkt **out, const char *line, size_t len)
 	return 0;
 }
 
+static int shallow_pkt(
+	git_pkt **out,
+	const char *line,
+	size_t len,
+	git_pkt_parse_data *data)
+{
+	git_pkt_shallow *pkt;
+	size_t oid_hexsize = git_oid_hexsize(data->oid_type);
+
+	GIT_ASSERT(data && data->oid_type);
+
+	pkt = git__calloc(1, sizeof(git_pkt_shallow));
+	GIT_ERROR_CHECK_ALLOC(pkt);
+
+	pkt->type = GIT_PKT_SHALLOW;
+
+	if (git__prefixncmp(line, len, "shallow "))
+		goto out_err;
+
+	line += 8;
+	len -= 8;
+
+	if (len != oid_hexsize)
+		goto out_err;
+
+	git_oid__fromstr(&pkt->oid, line, data->oid_type);
+	line += oid_hexsize + 1;
+	len -= oid_hexsize + 1;
+
+	*out = (git_pkt *)pkt;
+
+	return 0;
+
+out_err:
+	git_error_set(GIT_ERROR_NET, "invalid packet line");
+	git__free(pkt);
+	return -1;
+}
+
+static int unshallow_pkt(
+	git_pkt **out,
+	const char *line,
+	size_t len,
+	git_pkt_parse_data *data)
+{
+	git_pkt_shallow *pkt;
+	size_t oid_hexsize = git_oid_hexsize(data->oid_type);
+
+	GIT_ASSERT(data && data->oid_type);
+
+	pkt = git__calloc(1, sizeof(git_pkt_shallow));
+	GIT_ERROR_CHECK_ALLOC(pkt);
+
+	pkt->type = GIT_PKT_UNSHALLOW;
+
+	if (git__prefixncmp(line, len, "unshallow "))
+		goto out_err;
+
+	line += 10;
+	len -= 10;
+
+	if (len != oid_hexsize)
+		goto out_err;
+
+	git_oid__fromstr(&pkt->oid, line, data->oid_type);
+	line += oid_hexsize + 1;
+	len -= oid_hexsize + 1;
+
+	*out = (git_pkt *) pkt;
+
+	return 0;
+
+out_err:
+	git_error_set(GIT_ERROR_NET, "invalid packet line");
+	git__free(pkt);
+	return -1;
+}
+
 static int parse_len(size_t *out, const char *line, size_t linelen)
 {
 	char num[PKT_LEN_SIZE + 1];
@@ -553,7 +638,7 @@ int git_pkt_parse_line(
 	else if (*line == GIT_SIDE_BAND_ERROR)
 		error = sideband_error_pkt(pkt, line, len);
 	else if (!git__prefixncmp(line, len, "ACK"))
-		error = ack_pkt(pkt, line, len);
+		error = ack_pkt(pkt, line, len, data);
 	else if (!git__prefixncmp(line, len, "NAK"))
 		error = nak_pkt(pkt);
 	else if (!git__prefixncmp(line, len, "ERR"))
@@ -566,6 +651,10 @@ int git_pkt_parse_line(
 		error = ng_pkt(pkt, line, len);
 	else if (!git__prefixncmp(line, len, "unpack"))
 		error = unpack_pkt(pkt, line, len);
+	else if (!git__prefixcmp(line, "shallow"))
+		error = shallow_pkt(pkt, line, len, data);
+	else if (!git__prefixcmp(line, "unshallow"))
+		error = unshallow_pkt(pkt, line, len, data);
 	else
 		error = ref_pkt(pkt, line, len, data);
 
@@ -638,6 +727,9 @@ static int buffer_want_with_caps(
 	if (caps->ofs_delta)
 		git_str_puts(&str, GIT_CAP_OFS_DELTA " ");
 
+	if (caps->shallow)
+		git_str_puts(&str, GIT_CAP_SHALLOW " ");
+
 	if (git_str_oom(&str))
 		return -1;
 
@@ -668,8 +760,7 @@ static int buffer_want_with_caps(
  */
 
 int git_pkt_buffer_wants(
-	const git_remote_head * const *refs,
-	size_t count,
+	const git_fetch_negotiation *wants,
 	transport_smart_caps *caps,
 	git_str *buf)
 {
@@ -679,7 +770,7 @@ int git_pkt_buffer_wants(
 	size_t oid_hexsize, want_len, i = 0;
 
 #ifdef GIT_EXPERIMENTAL_SHA256
-	oid_type = count > 0 ? refs[0]->oid.type : GIT_OID_SHA1;
+	oid_type = wants->refs_len > 0 ? wants->refs[0]->oid.type : GIT_OID_SHA1;
 #else
 	oid_type = GIT_OID_SHA1;
 #endif
@@ -690,20 +781,20 @@ int git_pkt_buffer_wants(
 	      oid_hexsize + 1 /* LF */;
 
 	if (caps->common) {
-		for (; i < count; ++i) {
-			head = refs[i];
+		for (; i < wants->refs_len; ++i) {
+			head = wants->refs[i];
 			if (!head->local)
 				break;
 		}
 
-		if (buffer_want_with_caps(refs[i], caps, oid_type, buf) < 0)
+		if (buffer_want_with_caps(wants->refs[i], caps, oid_type, buf) < 0)
 			return -1;
 
 		i++;
 	}
 
-	for (; i < count; ++i) {
-		head = refs[i];
+	for (; i < wants->refs_len; ++i) {
+		head = wants->refs[i];
 
 		if (head->local)
 			continue;
@@ -718,6 +809,36 @@ int git_pkt_buffer_wants(
 			return -1;
 	}
 
+	/* Tell the server about our shallow objects */
+	for (i = 0; i < wants->shallow_roots_len; i++) {
+		char oid[GIT_OID_MAX_HEXSIZE + 1];
+		git_str shallow_buf = GIT_STR_INIT;
+
+		git_oid_tostr(oid, GIT_OID_MAX_HEXSIZE + 1, &wants->shallow_roots[i]);
+		git_str_puts(&shallow_buf, "shallow ");
+		git_str_puts(&shallow_buf, oid);
+		git_str_putc(&shallow_buf, '\n');
+
+		git_str_printf(buf, "%04x%s", (unsigned int)git_str_len(&shallow_buf) + 4, git_str_cstr(&shallow_buf));
+
+		git_str_dispose(&shallow_buf);
+
+		if (git_str_oom(buf))
+			return -1;
+	}
+
+	if (wants->depth > 0) {
+		git_str deepen_buf = GIT_STR_INIT;
+
+		git_str_printf(&deepen_buf, "deepen %d\n", wants->depth);
+		git_str_printf(buf,"%04x%s", (unsigned int)git_str_len(&deepen_buf) + 4, git_str_cstr(&deepen_buf));
+
+		git_str_dispose(&deepen_buf);
+
+		if (git_str_oom(buf))
+			return -1;
+	}
+
 	return git_pkt_buffer_flush(buf);
 }
 
diff --git a/src/libgit2/transports/smart_protocol.c b/src/libgit2/transports/smart_protocol.c
index 0d47acafe..488ef07c0 100644
--- a/src/libgit2/transports/smart_protocol.c
+++ b/src/libgit2/transports/smart_protocol.c
@@ -243,6 +243,12 @@ int git_smart__detect_caps(
 			continue;
 		}
 
+		if (!git__prefixcmp(ptr, GIT_CAP_SHALLOW)) {
+			caps->common = caps->shallow = 1;
+			ptr += strlen(GIT_CAP_SHALLOW);
+			continue;
+		}
+
 		/* We don't know this capability, so skip it */
 		ptr = strchr(ptr, ' ');
 	}
@@ -250,13 +256,20 @@ int git_smart__detect_caps(
 	return 0;
 }
 
-static int recv_pkt(git_pkt **out_pkt, git_pkt_type *out_type, gitno_buffer *buf)
+static int recv_pkt(
+	git_pkt **out_pkt,
+	git_pkt_type *out_type,
+	transport_smart *t,
+	gitno_buffer *buf)
 {
 	const char *ptr = buf->data, *line_end = ptr;
 	git_pkt *pkt = NULL;
 	git_pkt_parse_data pkt_parse_data = { 0 };
 	int error = 0, ret;
 
+	pkt_parse_data.oid_type = t->owner->repo->oid_type;
+	pkt_parse_data.seen_capabilities = 1;
+
 	do {
 		if (buf->offset > 0)
 			error = git_pkt_parse_line(&pkt, &line_end, ptr, buf->offset, &pkt_parse_data);
@@ -297,7 +310,7 @@ static int store_common(transport_smart *t)
 	int error;
 
 	do {
-		if ((error = recv_pkt(&pkt, NULL, buf)) < 0)
+		if ((error = recv_pkt(&pkt, NULL, t, buf)) < 0)
 			return error;
 
 		if (pkt->type != GIT_PKT_ACK) {
@@ -314,7 +327,7 @@ static int store_common(transport_smart *t)
 	return 0;
 }
 
-static int wait_while_ack(gitno_buffer *buf)
+static int wait_while_ack(transport_smart *t, gitno_buffer *buf)
 {
 	int error;
 	git_pkt *pkt = NULL;
@@ -323,7 +336,7 @@ static int wait_while_ack(gitno_buffer *buf)
 	while (1) {
 		git_pkt_free(pkt);
 
-		if ((error = recv_pkt(&pkt, NULL, buf)) < 0)
+		if ((error = recv_pkt(&pkt, NULL, t, buf)) < 0)
 			return error;
 
 		if (pkt->type == GIT_PKT_NAK)
@@ -344,7 +357,48 @@ static int wait_while_ack(gitno_buffer *buf)
 	return 0;
 }
 
-int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, const git_remote_head * const *wants, size_t count)
+static int cap_not_sup_err(const char *cap_name)
+{
+	git_error_set(GIT_ERROR_NET, "server doesn't support %s", cap_name);
+	return GIT_EINVALID;
+}
+
+/* Disables server capabilities we're not interested in */
+static int setup_caps(
+	transport_smart_caps *caps,
+	const git_fetch_negotiation *wants)
+{
+	if (wants->depth > 0) {
+		if (!caps->shallow)
+			return cap_not_sup_err(GIT_CAP_SHALLOW);
+	} else {
+		caps->shallow = 0;
+	}
+
+	return 0;
+}
+
+static int setup_shallow_roots(
+	git_array_oid_t *out,
+	const git_fetch_negotiation *wants)
+{
+	git_array_clear(*out);
+
+	if (wants->shallow_roots_len > 0) {
+		git_array_init_to_size(*out, wants->shallow_roots_len);
+		GIT_ERROR_CHECK_ALLOC(out->ptr);
+
+		memcpy(out->ptr, wants->shallow_roots,
+		       sizeof(git_oid) * wants->shallow_roots_len);
+	}
+
+	return 0;
+}
+
+int git_smart__negotiate_fetch(
+	git_transport *transport,
+	git_repository *repo,
+	const git_fetch_negotiation *wants)
 {
 	transport_smart *t = (transport_smart *)transport;
 	git_revwalk__push_options opts = GIT_REVWALK__PUSH_OPTIONS_INIT;
@@ -356,7 +410,11 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 	unsigned int i;
 	git_oid oid;
 
-	if ((error = git_pkt_buffer_wants(wants, count, &t->caps, &data)) < 0)
+	if ((error = setup_caps(&t->caps, wants)) < 0 ||
+	    (error = setup_shallow_roots(&t->shallow_roots, wants)) < 0)
+		return error;
+
+	if ((error = git_pkt_buffer_wants(wants, &t->caps, &data)) < 0)
 		return error;
 
 	if ((error = git_revwalk_new(&walk, repo)) < 0)
@@ -366,6 +424,37 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 	if ((error = git_revwalk__push_glob(walk, "refs/*", &opts)) < 0)
 		goto on_error;
 
+	if (wants->depth > 0) {
+		git_pkt_shallow *pkt;
+
+		if ((error = git_smart__negotiation_step(&t->parent, data.ptr, data.size)) < 0)
+			goto on_error;
+
+		while ((error = recv_pkt((git_pkt **)&pkt, NULL, t, buf)) == 0) {
+			bool complete = false;
+
+			if (pkt->type == GIT_PKT_SHALLOW) {
+				error = git_oidarray__add(&t->shallow_roots, &pkt->oid);
+			} else if (pkt->type == GIT_PKT_UNSHALLOW) {
+				git_oidarray__remove(&t->shallow_roots, &pkt->oid);
+			} else if (pkt->type == GIT_PKT_FLUSH) {
+				/* Server is done, stop processing shallow oids */
+				complete = true;
+			} else {
+				git_error_set(GIT_ERROR_NET, "unexpected packet type");
+				error = -1;
+			}
+
+			git_pkt_free((git_pkt *) pkt);
+
+			if (complete || error < 0)
+				break;
+		}
+
+		if (error < 0)
+			goto on_error;
+	}
+
 	/*
 	 * Our support for ACK extensions is simply to parse them. On
 	 * the first ACK we will accept that as enough common
@@ -406,7 +495,7 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 				if ((error = store_common(t)) < 0)
 					goto on_error;
 			} else {
-				if ((error = recv_pkt(NULL, &pkt_type, buf)) < 0)
+				if ((error = recv_pkt(NULL, &pkt_type, t, buf)) < 0)
 					goto on_error;
 
 				if (pkt_type == GIT_PKT_ACK) {
@@ -428,7 +517,7 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 			git_pkt_ack *pkt;
 			unsigned int j;
 
-			if ((error = git_pkt_buffer_wants(wants, count, &t->caps, &data)) < 0)
+			if ((error = git_pkt_buffer_wants(wants, &t->caps, &data)) < 0)
 				goto on_error;
 
 			git_vector_foreach(&t->common, j, pkt) {
@@ -448,7 +537,7 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 		git_pkt_ack *pkt;
 		unsigned int j;
 
-		if ((error = git_pkt_buffer_wants(wants, count, &t->caps, &data)) < 0)
+		if ((error = git_pkt_buffer_wants(wants, &t->caps, &data)) < 0)
 			goto on_error;
 
 		git_vector_foreach(&t->common, j, pkt) {
@@ -466,10 +555,11 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 		goto on_error;
 
 	if (t->cancelled.val) {
-		git_error_set(GIT_ERROR_NET, "The fetch was cancelled by the user");
+		git_error_set(GIT_ERROR_NET, "the fetch was cancelled");
 		error = GIT_EUSER;
 		goto on_error;
 	}
+
 	if ((error = git_smart__negotiation_step(&t->parent, data.ptr, data.size)) < 0)
 		goto on_error;
 
@@ -478,7 +568,7 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 
 	/* Now let's eat up whatever the server gives us */
 	if (!t->caps.multi_ack && !t->caps.multi_ack_detailed) {
-		if ((error = recv_pkt(NULL, &pkt_type, buf)) < 0)
+		if ((error = recv_pkt(NULL, &pkt_type, t, buf)) < 0)
 			return error;
 
 		if (pkt_type != GIT_PKT_ACK && pkt_type != GIT_PKT_NAK) {
@@ -486,7 +576,7 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 			return -1;
 		}
 	} else {
-		error = wait_while_ack(buf);
+		error = wait_while_ack(t, buf);
 	}
 
 	return error;
@@ -497,6 +587,25 @@ on_error:
 	return error;
 }
 
+int git_smart__shallow_roots(git_oidarray *out, git_transport *transport)
+{
+	transport_smart *t = (transport_smart *)transport;
+	size_t len;
+
+	GIT_ERROR_CHECK_ALLOC_MULTIPLY(&len, t->shallow_roots.size, sizeof(git_oid));
+
+	out->count = t->shallow_roots.size;
+
+	if (len) {
+		out->ids = git__malloc(len);
+		memcpy(out->ids, t->shallow_roots.ptr, len);
+	} else {
+		out->ids = NULL;
+	}
+
+	return 0;
+}
+
 static int no_sideband(transport_smart *t, struct git_odb_writepack *writepack, gitno_buffer *buf, git_indexer_progress *stats)
 {
 	int recvd;
@@ -602,7 +711,7 @@ int git_smart__download_pack(
 			goto done;
 		}
 
-		if ((error = recv_pkt(&pkt, NULL, buf)) >= 0) {
+		if ((error = recv_pkt(&pkt, NULL, t, buf)) >= 0) {
 			/* Check cancellation after network call */
 			if (t->cancelled.val) {
 				git_error_clear();