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[RFC/WIP PATCH 04/11] upload-pack-2: Implement the version 2 of upload-pack

From
Stefan Beller <sbeller@google.com>
Date
May 26, 2015, 22:01 UTC
Message-ID
<1432677675-5118-5-git-send-email-sbeller@google.com>
In-Reply-To
<1432677675-5118-1-git-send-email-sbeller@google.com>

In upload-pack-2 we send each capability in its own packet. By reusing the advertise_capabilities and eventually setting it to NULL we will be able to reuse the methods for refs advertisement.

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 .gitignore      |  1 +
 Makefile        |  2 ++
 upload-pack-2.c |  1 +
 upload-pack.c   | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++++++---
 4 files changed, 78 insertions(+), 3 deletions(-)
 create mode 120000 upload-pack-2.c
diff --git a/.gitignore b/.gitignore
index a052419..a3c8ab9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -165,6 +165,7 @@
 /git-update-server-info
 /git-upload-archive
 /git-upload-pack
+/git-upload-pack-2
 /git-var
 /git-verify-commit
 /git-verify-pack
diff --git a/Makefile b/Makefile
index 25a453b..0f3ee41 100644
--- a/Makefile
+++ b/Makefile
@@ -560,6 +560,7 @@ PROGRAM_OBJS += sh-i18n--envsubst.o
 PROGRAM_OBJS += shell.o
 PROGRAM_OBJS += show-index.o
 PROGRAM_OBJS += upload-pack.o
+PROGRAM_OBJS += upload-pack-2.o
 PROGRAM_OBJS += remote-testsvn.o
 
 # Binary suffix, set to .exe for Windows builds
@@ -625,6 +626,7 @@ OTHER_PROGRAMS = git$X
 # what test wrappers are needed and 'install' will install, in bindir
 BINDIR_PROGRAMS_NEED_X += git
 BINDIR_PROGRAMS_NEED_X += git-upload-pack
+BINDIR_PROGRAMS_NEED_X += git-upload-pack-2
 BINDIR_PROGRAMS_NEED_X += git-receive-pack
 BINDIR_PROGRAMS_NEED_X += git-upload-archive
 BINDIR_PROGRAMS_NEED_X += git-shell
diff --git a/upload-pack-2.c b/upload-pack-2.c
new file mode 120000
index 0000000..e30a871
--- /dev/null
+++ b/upload-pack-2.c
@@ -0,0 +1 @@
+upload-pack.c
\ No newline at end of file
diff --git a/upload-pack.c b/upload-pack.c
index a5f75b7..84f9ee3 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -716,10 +716,47 @@ static void format_symref_info(struct strbuf *buf, struct string_list *symref)
 		strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util);
 }
 
-static const char *advertise_capabilities = "multi_ack thin-pack side-band"
+static char *advertise_capabilities = "multi_ack thin-pack side-band"
 		" side-band-64k ofs-delta shallow no-progress"
 		" include-tag multi_ack_detailed";
 
+/*
+ * Reads the next capability and puts it into dst as a null terminated string.
+ * Returns true if more capabilities can be read.
+ * */
+static int next_capability(char *dst)
+{
+	int len = 0;
+	if (!*advertise_capabilities) {
+		/* make sure to not advertise capabilities afterwards */
+		advertise_capabilities = NULL;
+		return 0;
+	}
+
+	while (advertise_capabilities[len] != '\0' &&
+	       advertise_capabilities[len] != ' ')
+		len ++;
+	strncpy(dst, advertise_capabilities, len);
+	dst[len] = '\0';
+
+	advertise_capabilities += len;
+	if (*advertise_capabilities == ' ')
+		advertise_capabilities++;
+
+	return 1;
+}
+
+static void send_capabilities(void)
+{
+	char buf[100];
+
+	while (next_capability(buf))
+		packet_write(1, "capability:%s\n", buf);
+
+	packet_write(1, "agent:%s\n", git_user_agent_sanitized());
+	packet_flush(1);
+}
+
 static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 {
 
@@ -794,6 +831,28 @@ static void upload_pack(void)
 	}
 }
 
+static void receive_capabilities(void)
+{
+	int done = 0;
+	while (1) {
+		char *line = packet_read_line(0, NULL);
+		if (!line)
+			break;
+		if (starts_with(line, "capability:"))
+			parse_features(line + strlen("capability:"));
+	}
+}
+
+static void upload_pack_version_2(void)
+{
+	send_capabilities();
+	receive_capabilities();
+
+	/* The rest of the protocol stays the same, capabilities advertising
+	   is disabled though. */
+	upload_pack();
+}
+
 static int upload_pack_config(const char *var, const char *value, void *unused)
 {
 	if (!strcmp("uploadpack.allowtipsha1inwant", var))
@@ -806,16 +865,24 @@ static int upload_pack_config(const char *var, const char *value, void *unused)
 	return parse_hide_refs_config(var, value, "uploadpack");
 }
 
+static int endswith(const char *teststring, const char *ending)
+{
+	int slen = strlen(teststring);
+	int elen = strlen(ending);
+	return !strcmp(teststring + slen - elen, ending);
+}
+
 int main(int argc, char **argv)
 {
 	char *dir;
+	const char *cmd;
 	int i;
 	int strict = 0;
 
 	git_setup_gettext();
 
 	packet_trace_identity("upload-pack");
-	git_extract_argv0_path(argv[0]);
+	cmd = git_extract_argv0_path(argv[0]);
 	check_replace_refs = 0;
 
 	for (i = 1; i < argc; i++) {
@@ -857,6 +924,10 @@ int main(int argc, char **argv)
 		die("'%s' does not appear to be a git repository", dir);
 
 	git_config(upload_pack_config, NULL);
-	upload_pack();
+
+	if (endswith(cmd, "-2"))
+		upload_pack_version_2();
+	else
+		upload_pack();
 	return 0;
 }

-- 
2.4.1.345.gab207b6.dirty
Previous: Stefan BellerNext: Eric Sunshine
Message 7 of 61 in “Protocol version 2, again!”
  1. 00/11 Protocol version 2, again!Stefan Beller, May 26, 2015
  2. 01/11 upload-pack: make client capability parsing code a separate functionStefan Beller, May 26, 2015
  3. 02/11 upload-pack: only accept capabilities on the first "want" lineStefan Beller, May 26, 2015
  4. Junio C HamanoMay 26, 2015
  5. Stefan BellerMay 26, 2015
  6. 03/11 upload-pack: move capabilities out of send_refStefan Beller, May 26, 2015
  7. 04/11 upload-pack-2: Implement the version 2 of upload-packStefan Beller, May 26, 2015
  8. Eric SunshineMay 27, 2015
  9. Jeff KingMay 27, 2015
  10. Eric SunshineMay 27, 2015
  11. Jeff KingMay 27, 2015
  12. Stefan BellerMay 27, 2015
  13. Jeff KingMay 27, 2015
  14. Stefan BellerMay 27, 2015
  15. Jeff KingMay 27, 2015
  16. 05/11 transport: add infrastructure to support a protocol version numberStefan Beller, May 26, 2015
  17. Jeff KingMay 27, 2015
  18. Stefan BellerMay 27, 2015
  19. Jeff KingMay 27, 2015
  20. Junio C HamanoMay 27, 2015
  21. 06/11 remote.h: add get_remote_capabilities, request_capabilitiesStefan Beller, May 26, 2015
  22. Eric SunshineMay 27, 2015
  23. Jeff KingMay 27, 2015
  24. Eric SunshineMay 27, 2015
  25. Jeff KingMay 27, 2015
  26. Jeff KingMay 27, 2015
  27. Stefan BellerMay 29, 2015
  28. Jeff KingMay 29, 2015
  29. 07/11 fetch-pack: use the configured transport protocolStefan Beller, May 26, 2015
  30. Junio C HamanoMay 26, 2015
  31. Stefan BellerMay 26, 2015
  32. Jeff KingMay 27, 2015
  33. 08/11 transport: connect_setup appends protocol version numberStefan Beller, May 26, 2015
  34. Junio C HamanoMay 26, 2015
  35. Stefan BellerMay 26, 2015
  36. Junio C HamanoMay 27, 2015
  37. Jeff KingMay 27, 2015
  38. Eric SunshineMay 27, 2015
  39. Jeff KingMay 27, 2015
  40. 09/11 transport: get_refs_via_connect exchanges capabilities before refs.Stefan Beller, May 26, 2015
  41. Eric SunshineMay 27, 2015
  42. Jeff KingMay 27, 2015
  43. 10/11 t5544: add a test case for the new protocolStefan Beller, May 26, 2015
  44. Eric SunshineMay 27, 2015
  45. Jeff KingMay 27, 2015
  46. 11/11 Document protocol version 2Stefan Beller, May 26, 2015
  47. Junio C HamanoMay 29, 2015
  48. Stefan BellerMay 29, 2015
  49. Junio C HamanoMay 29, 2015
  50. Jeff KingMay 29, 2015
  51. Stefan BellerJun 1, 2015
  52. Stefan BellerJun 1, 2015
  53. Jeff KingJun 4, 2015
  54. Junio C HamanoJun 4, 2015
  55. Junio C HamanoJun 2, 2015
  56. Jeff KingMay 27, 2015
  57. Jeff KingMay 27, 2015
  58. Stefan BellerJun 1, 2015
  59. Duy NguyenJun 2, 2015
  60. Jeff KingJun 4, 2015
  61. Stefan BellerJun 4, 2015

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