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[RFC PATCH v2 01/16] pkt-line: Add strbuf based functions

From
Shawn O. Pearce <spearce@spearce.org>
Date
Oct 13, 2009, 02:25 UTC
Message-ID
<1255400715-10508-2-git-send-email-spearce@spearce.org>
In-Reply-To
<1255400715-10508-1-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 |   81 +++++++++++++++++++++++++++++++++++++++++++++++++++---------
 pkt-line.h |    4 +++
 2 files changed, 73 insertions(+), 12 deletions(-)
diff --git a/pkt-line.c b/pkt-line.c
index b691abe..2333d96 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(unsigned *ret_len, const char *linelen)
 {
 	int n;
-	unsigned len;
-	char linelen[4];
-
-	safe_read(fd, linelen, 4);
+	unsigned 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;
 	}
+	*ret_len = len;
+	return 0;
+}
+
+int packet_read_line(int fd, char *buffer, unsigned size)
+{
+	unsigned len;
+	char linelen[4];
+
+	safe_read(fd, linelen, 4);
+	if (packet_length(&len, linelen))
+		die("protocol error: bad line length character");
 	if (!len)
 		return 0;
 	len -= 4;
@@ -107,3 +139,28 @@ 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)
+{
+	unsigned len;
+
+	if (*src_len < 4 || packet_length(&len, *src_buf))
+		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
-- 
1.6.5.52.g0ff2e
Previous: Shawn O. PearceNext: Johannes Sixt
Message 2 of 38 in “Return of smart HTTP”
  1. 00/16 Return of smart HTTPShawn O. Pearce, Oct 13, 2009
  2. 01/16 pkt-line: Add strbuf based functionsShawn O. Pearce, Oct 13, 2009
  3. Johannes SixtOct 13, 2009
  4. Shawn O. PearceOct 13, 2009
  5. 02/16 pkt-line: Make packet_read_line easier to debugShawn O. Pearce, Oct 13, 2009
  6. 03/16 fetch-pack: Use a strbuf to compose the want listShawn O. Pearce, Oct 13, 2009
  7. 04/16 Move "get_ack()" back to fetch-packShawn O. Pearce, Oct 13, 2009
  8. 05/16 Add multi_ack_2 capability to fetch-pack/upload-packShawn O. Pearce, Oct 13, 2009
  9. Jakub NarebskiOct 13, 2009
  10. Shawn O. PearceOct 13, 2009
  11. 06/16 remote-curl: Refactor walker initializationShawn O. Pearce, Oct 13, 2009
  12. 07/16 remote-helpers: Fetch more than one ref in a batchShawn O. Pearce, Oct 13, 2009
  13. Daniel BarkalowOct 13, 2009
  14. Shawn O. PearceOct 13, 2009
  15. 08/16 remote-helpers: Support custom transport optionsShawn O. Pearce, Oct 13, 2009
  16. Daniel BarkalowOct 13, 2009
  17. Shawn O. PearceOct 13, 2009
  18. Daniel BarkalowOct 13, 2009
  19. Shawn O. PearceOct 13, 2009
  20. Daniel BarkalowOct 13, 2009
  21. Shawn O. PearceOct 13, 2009
  22. 09/16 Move WebDAV HTTP push under remote-curlShawn O. Pearce, Oct 13, 2009
  23. Mike HommeyOct 13, 2009
  24. Johannes SchindelinOct 13, 2009
  25. 10/16 Git-aware CGI to provide dumb HTTP transportShawn O. Pearce, Oct 13, 2009
  26. Johannes SixtOct 13, 2009
  27. 11/16 Add one shot RPC options to upload-pack, receive-packShawn O. Pearce, Oct 13, 2009
  28. 12/16 Smart fetch and push over HTTP: server sideShawn O. Pearce, Oct 13, 2009
  29. Johannes SixtOct 13, 2009
  30. Shawn O. PearceOct 13, 2009
  31. 13/16 Discover refs via smart HTTP server when availableShawn O. Pearce, Oct 13, 2009
  32. 14/16 Smart push over HTTP: client sideShawn O. Pearce, Oct 13, 2009
  33. Felipe ContrerasOct 13, 2009
  34. 15/16 Smart fetch over HTTP: client sideShawn O. Pearce, Oct 13, 2009
  35. 16/16 Smart HTTP fetch: gzip requestsShawn O. Pearce, Oct 13, 2009
  36. Junio C HamanoOct 13, 2009
  37. eduard stefanOct 13, 2009
  38. Junio C HamanoOct 13, 2009

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