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[RFC PATCH v4 02/26] pkt-line: Add strbuf based functions

From
Shawn O. Pearce <spearce@spearce.org>
Date
Oct 29, 2009, 00:00 UTC
Message-ID
<1256774448-7625-3-git-send-email-spearce@spearce.org>
In-Reply-To
<1256774448-7625-1-git-send-email-spearce@spearce.org>

These routines help to work with pkt-line values inside of a strbuf, permitting simple formatting of buffered network messages.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
---
 pkt-line.c |   84 +++++++++++++++++++++++++++++++++++++++++++++++++++--------
 pkt-line.h |    4 +++
 2 files changed, 76 insertions(+), 12 deletions(-)
diff --git a/pkt-line.c b/pkt-line.c
index b691abe..bd603f8 100644
--- a/pkt-line.c
+++ b/pkt-line.c
@@ -42,17 +42,19 @@ void packet_flush(int fd)
 	safe_write(fd, "0000", 4);
 }
 
+void packet_buf_flush(struct strbuf *buf)
+{
+	strbuf_add(buf, "0000", 4);
+}
+
 #define hex(a) (hexchar[(a) & 15])
-void packet_write(int fd, const char *fmt, ...)
+static char buffer[1000];
+static unsigned format_packet(const char *fmt, va_list args)
 {
-	static char buffer[1000];
 	static char hexchar[] = "0123456789abcdef";
-	va_list args;
 	unsigned n;
 
-	va_start(args, fmt);
 	n = vsnprintf(buffer + 4, sizeof(buffer) - 4, fmt, args);
-	va_end(args);
 	if (n >= sizeof(buffer)-4)
 		die("protocol error: impossibly long line");
 	n += 4;
@@ -60,9 +62,31 @@ void packet_write(int fd, const char *fmt, ...)
 	buffer[1] = hex(n >> 8);
 	buffer[2] = hex(n >> 4);
 	buffer[3] = hex(n);
+	return n;
+}
+
+void packet_write(int fd, const char *fmt, ...)
+{
+	va_list args;
+	unsigned n;
+
+	va_start(args, fmt);
+	n = format_packet(fmt, args);
+	va_end(args);
 	safe_write(fd, buffer, n);
 }
 
+void packet_buf_write(struct strbuf *buf, const char *fmt, ...)
+{
+	va_list args;
+	unsigned n;
+
+	va_start(args, fmt);
+	n = format_packet(fmt, args);
+	va_end(args);
+	strbuf_add(buf, buffer, n);
+}
+
 static void safe_read(int fd, void *buffer, unsigned size)
 {
 	ssize_t ret = read_in_full(fd, buffer, size);
@@ -72,15 +96,11 @@ static void safe_read(int fd, void *buffer, unsigned size)
 		die("The remote end hung up unexpectedly");
 }
 
-int packet_read_line(int fd, char *buffer, unsigned size)
+static int packet_length(const char *linelen)
 {
 	int n;
-	unsigned len;
-	char linelen[4];
-
-	safe_read(fd, linelen, 4);
+	int len = 0;
 
-	len = 0;
 	for (n = 0; n < 4; n++) {
 		unsigned char c = linelen[n];
 		len <<= 4;
@@ -96,8 +116,20 @@ int packet_read_line(int fd, char *buffer, unsigned size)
 			len += c - 'A' + 10;
 			continue;
 		}
-		die("protocol error: bad line length character");
+		return -1;
 	}
+	return len;
+}
+
+int packet_read_line(int fd, char *buffer, unsigned size)
+{
+	int len;
+	char linelen[4];
+
+	safe_read(fd, linelen, 4);
+	len = packet_length(linelen);
+	if (len < 0)
+		die("protocol error: bad line length character");
 	if (!len)
 		return 0;
 	len -= 4;
@@ -107,3 +139,31 @@ int packet_read_line(int fd, char *buffer, unsigned size)
 	buffer[len] = 0;
 	return len;
 }
+
+int packet_get_line(struct strbuf *out,
+	char **src_buf, size_t *src_len)
+{
+	int len;
+
+	if (*src_len < 4)
+		return -1;
+	len = packet_length(*src_buf);
+	if (len < 0)
+		return -1;
+	if (!len) {
+		*src_buf += 4;
+		*src_len -= 4;
+		return 0;
+	}
+	if (*src_len < len)
+		return -2;
+
+	*src_buf += 4;
+	*src_len -= 4;
+	len -= 4;
+
+	strbuf_add(out, *src_buf, len);
+	*src_buf += len;
+	*src_len -= len;
+	return len;
+}
diff --git a/pkt-line.h b/pkt-line.h
index 9df653f..1e5dcfe 100644
--- a/pkt-line.h
+++ b/pkt-line.h
@@ -2,14 +2,18 @@
 #define PKTLINE_H
 
 #include "git-compat-util.h"
+#include "strbuf.h"
 
 /*
  * Silly packetized line writing interface
  */
 void packet_flush(int fd);
 void packet_write(int fd, const char *fmt, ...) __attribute__((format (printf, 2, 3)));
+void packet_buf_flush(struct strbuf *buf);
+void packet_buf_write(struct strbuf *buf, const char *fmt, ...) __attribute__((format (printf, 2, 3)));
 
 int packet_read_line(int fd, char *buffer, unsigned size);
+int packet_get_line(struct strbuf *out, char **src_buf, size_t *src_len);
 ssize_t safe_write(int, const void *, ssize_t);
 
 #endif
-- 
1.6.5.2.181.gd6f41
Previous: Shawn O. PearceNext: Shawn O. Pearce
Message 3 of 60 in “Return of smart HTTP”
  1. 00/26 Return of smart HTTPShawn O. Pearce, Oct 29, 2009
  2. 01/26 http-push: fix check condition on http.c::finish_http_pack_request()Shawn O. Pearce, Oct 29, 2009
  3. 02/26 pkt-line: Add strbuf based functionsShawn O. Pearce, Oct 29, 2009
  4. 03/26 pkt-line: Make packet_read_line easier to debugShawn O. Pearce, Oct 29, 2009
  5. Junio C HamanoOct 29, 2009
  6. Shawn O. PearceOct 29, 2009
  7. Junio C HamanoOct 29, 2009
  8. Shawn O. PearceOct 29, 2009
  9. Jeff KingOct 30, 2009
  10. Shawn O. PearceOct 30, 2009
  11. Jeff KingOct 30, 2009
  12. David BrownOct 30, 2009
  13. Junio C HamanoOct 30, 2009
  14. 04/26 fetch-pack: Use a strbuf to compose the want listShawn O. Pearce, Oct 29, 2009
  15. 05/26 Move "get_ack()" back to fetch-packShawn O. Pearce, Oct 29, 2009
  16. Junio C HamanoOct 29, 2009
  17. Shawn O. PearceOct 29, 2009
  18. 06/26 Add multi_ack_detailed capability to fetch-pack/upload-packShawn O. Pearce, Oct 29, 2009
  19. Junio C HamanoOct 29, 2009
  20. Shawn O. PearceOct 29, 2009
  21. 07/26 remote-curl: Refactor walker initializationShawn O. Pearce, Oct 29, 2009
  22. 08/26 fetch: Allow transport -v -v -v to set verbosity to 3Shawn O. Pearce, Oct 29, 2009
  23. 09/26 remote-helpers: Fetch more than one ref in a batchShawn O. Pearce, Oct 29, 2009
  24. 10/26 remote-helpers: Support custom transport optionsShawn O. Pearce, Oct 29, 2009
  25. 11/26 Move WebDAV HTTP push under remote-curlShawn O. Pearce, Oct 29, 2009
  26. Tay Ray ChuanOct 30, 2009
  27. Shawn O. PearceOct 31, 2009
  28. Tay Ray ChuanOct 30, 2009
  29. Clemens BuchacherOct 30, 2009
  30. Tay Ray ChuanOct 30, 2009
  31. 12/26 remote-helpers: return successfully if everything up-to-dateShawn O. Pearce, Oct 29, 2009
  32. 13/26 Git-aware CGI to provide dumb HTTP transportShawn O. Pearce, Oct 29, 2009
  33. 14/26 Add stateless RPC options to upload-pack, receive-packShawn O. Pearce, Oct 29, 2009
  34. Junio C HamanoOct 29, 2009
  35. Shawn O. PearceOct 29, 2009
  36. Junio C HamanoOct 29, 2009
  37. Shawn O. PearceOct 30, 2009
  38. 15/26 Smart fetch and push over HTTP: server sideShawn O. Pearce, Oct 29, 2009
  39. 16/26 http-backend: add GIT_PROJECT_ROOT environment varShawn O. Pearce, Oct 29, 2009
  40. 17/26 http-backend: reword some documentationShawn O. Pearce, Oct 29, 2009
  41. 18/26 http-backend: use mod_alias instead of mod_rewriteShawn O. Pearce, Oct 29, 2009
  42. 19/26 http-backend: add example for gitweb on same URLShawn O. Pearce, Oct 29, 2009
  43. 20/26 http-backend: more explict LocationMatchShawn O. Pearce, Oct 29, 2009
  44. 21/26 Discover refs via smart HTTP server when availableShawn O. Pearce, Oct 29, 2009
  45. 22/26 Smart push over HTTP: client sideShawn O. Pearce, Oct 29, 2009
  46. 23/26 Smart fetch over HTTP: client sideShawn O. Pearce, Oct 29, 2009
  47. 24/26 Smart HTTP fetch: gzip requestsShawn O. Pearce, Oct 29, 2009
  48. 25/26 t5540-http-push: remove redundant fetchesShawn O. Pearce, Oct 29, 2009
  49. 26/26 test smart http fetch and pushShawn O. Pearce, Oct 29, 2009
  50. Clemens BuchacherOct 29, 2009
  51. Shawn O. PearceOct 29, 2009
  52. Junio C HamanoOct 29, 2009
  53. Shawn O. PearceOct 29, 2009
  54. Shawn O. PearceOct 29, 2009
  55. Junio C HamanoOct 30, 2009
  56. Shawn O. PearceOct 30, 2009
  57. Tay Ray ChuanOct 30, 2009
  58. Shawn O. PearceOct 31, 2009
  59. Jakub NarebskiOct 29, 2009
  60. Shawn O. PearceOct 29, 2009

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