smart: support shallow capability in smart transport

libgit2 · tiennou · Oct 25, 2018 · Dec 15, 2017 · Aug 2, 2018 · Aug 2, 2018
commit a888aaa3e83f6c6d5dfcef9cd2df5aee2b49d99f
diff --git a/src/transports/smart.h b/src/transports/smart.h
@@ -30,6 +30,7 @@
 #define GIT_CAP_REPORT_STATUS "report-status"
 #define GIT_CAP_THIN_PACK "thin-pack"
 #define GIT_CAP_SYMREF "symref"
+#define GIT_CAP_SHALLOW "shallow"
 
 extern bool git_smart__ofs_delta_enabled;
 
@@ -47,6 +48,8 @@ typedef enum {
 	GIT_PKT_OK,
 	GIT_PKT_NG,
 	GIT_PKT_UNPACK,
+	GIT_PKT_SHALLOW,
+	GIT_PKT_UNSHALLOW,
 } git_pkt_type;
 
 /* Used for multi_ack and multi_ack_detailed */
@@ -118,6 +121,11 @@ 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 {
 	int common:1,
 		ofs_delta:1,
@@ -128,7 +136,8 @@ typedef struct transport_smart_caps {
 		include_tag:1,
 		delete_refs:1,
 		report_status:1,
-		thin_pack:1;
+		thin_pack:1,
+		shallow:1;
 } transp
8000
ort_smart_caps;
 
 typedef int (*packetsize_cb)(size_t received, void *payload);

diff --git a/src/transports/smart_pkt.c b/src/transports/smart_pkt.c
@@ -363,6 +363,50 @@ 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_shallow *pkt;
+
+	pkt = git__calloc(1, sizeof(git_pkt_shallow));
+	GIT_ERROR_CHECK_ALLOC(pkt);
+
+	pkt->type = GIT_PKT_SHALLOW;
+	line += 7;
+	len -= 7;
+
+	if (len >= GIT_OID_HEXSZ) {
+		git_oid_fromstr(&pkt->oid, line + 1);
+		line += GIT_OID_HEXSZ + 1;
+		len -= GIT_OID_HEXSZ + 1;
+	}
+
+	*out = (git_pkt *) pkt;
+
+	return 0;
+}
+
+static int unshallow_pkt(git_pkt **out, const char *line, size_t len)
+{
+	git_pkt_shallow *pkt;
+
+	pkt = git__calloc(1, sizeof(git_pkt_shallow));
+	GIT_ERROR_CHECK_ALLOC(pkt);
+
+	pkt->type = GIT_PKT_UNSHALLOW;
+	line += 9;
+	len -= 9;
+
+	if (len >= GIT_OID_HEXSZ) {
+		git_oid_fromstr(&pkt->oid, line + 1);
+		line += GIT_OID_HEXSZ + 1;
+		len -= GIT_OID_HEXSZ + 1;
+	}
+
+	*out = (git_pkt *) pkt;
+
+	return 0;
+}
+
 static int parse_len(size_t *out, const char *line, size_t linelen)
 {
 	char num[PKT_LEN_SIZE + 1];
@@ -489,6 +533,10 @@ 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);
+	else if (!git__prefixcmp(line, "unshallow"))
+		error = unshallow_pkt(pkt, line, len);
 	else
 		error = ref_pkt(pkt, line, len);
 
@@ -554,6 +602,9 @@ static int buffer_want_with_caps(const git_remote_head *head, transport_smart_ca
 	if (caps->ofs_delta)
 		git_buf_puts(&str, GIT_CAP_OFS_DELTA " ");
 
+	if (caps->shallow)
+		git_buf_puts(&str, GIT_CAP_SHALLOW " ");
+
 	if (git_buf_oom(&str))
 		return -1;
 

diff --git a/src/transports/smart_protocol.c b/src/transports/smart_protocol.c
@@ -202,6 +202,12 @@ int git_smart__detect_caps(git_pkt_ref *pkt, transport_smart_caps *caps, git_vec
 			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, ' ');
 	}