1 files changed, 133 insertions, 105 deletions

diff --git a/pkt-line.c b/pkt-line.c
index 5a04984ea3..62fdb37079 100644
--- a/pkt-line.c
+++ b/pkt-line.c
@@ -1,91 +1,94 @@
 #include "cache.h"
 #include "pkt-line.h"
+#include "run-command.h"
 
+char packet_buffer[LARGE_PACKET_MAX];
 static const char *packet_trace_prefix = "git";
-static const char trace_key[] = "GIT_TRACE_PACKET";
+static struct trace_key trace_packet = TRACE_KEY_INIT(PACKET);
+static struct trace_key trace_pack = TRACE_KEY_INIT(PACKFILE);
 
 void packet_trace_identity(const char *prog)
 {
 	packet_trace_prefix = xstrdup(prog);
 }
 
+static const char *get_trace_prefix(void)
+{
+	return in_async() ? "sideband" : packet_trace_prefix;
+}
+
+static int packet_trace_pack(const char *buf, unsigned int len, int sideband)
+{
+	if (!sideband) {
+		trace_verbatim(&trace_pack, buf, len);
+		return 1;
+	} else if (len && *buf == '\1') {
+		trace_verbatim(&trace_pack, buf + 1, len - 1);
+		return 1;
+	} else {
+		/* it's another non-pack sideband */
+		return 0;
+	}
+}
+
 static void packet_trace(const char *buf, unsigned int len, int write)
 {
 	int i;
 	struct strbuf out;
+	static int in_pack, sideband;
+
+	if (!trace_want(&trace_packet) && !trace_want(&trace_pack))
+		return;
 
-	if (!trace_want(trace_key))
+	if (in_pack) {
+		if (packet_trace_pack(buf, len, sideband))
+			return;
+	} else if (starts_with(buf, "PACK") || starts_with(buf, "\1PACK")) {
+		in_pack = 1;
+		sideband = *buf == '\1';
+		packet_trace_pack(buf, len, sideband);
+
+		/*
+		 * Make a note in the human-readable trace that the pack data
+		 * started.
+		 */
+		buf = "PACK ...";
+		len = strlen(buf);
+	}
+
+	if (!trace_want(&trace_packet))
 		return;
 
 	/* +32 is just a guess for header + quoting */
 	strbuf_init(&out, len+32);
 
 	strbuf_addf(&out, "packet: %12s%c ",
-		    packet_trace_prefix, write ? '>' : '<');
+		    get_trace_prefix(), write ? '>' : '<');
 
-	if ((len >= 4 && !prefixcmp(buf, "PACK")) ||
-	    (len >= 5 && !prefixcmp(buf+1, "PACK"))) {
-		strbuf_addstr(&out, "PACK ...");
-		unsetenv(trace_key);
-	}
-	else {
-		/* XXX we should really handle printable utf8 */
-		for (i = 0; i < len; i++) {
-			/* suppress newlines */
-			if (buf[i] == '\n')
-				continue;
-			if (buf[i] >= 0x20 && buf[i] <= 0x7e)
-				strbuf_addch(&out, buf[i]);
-			else
-				strbuf_addf(&out, "\\%o", buf[i]);
-		}
+	/* XXX we should really handle printable utf8 */
+	for (i = 0; i < len; i++) {
+		/* suppress newlines */
+		if (buf[i] == '\n')
+			continue;
+		if (buf[i] >= 0x20 && buf[i] <= 0x7e)
+			strbuf_addch(&out, buf[i]);
+		else
+			strbuf_addf(&out, "\\%o", buf[i]);
 	}
 
 	strbuf_addch(&out, '\n');
-	trace_strbuf(trace_key, &out);
+	trace_strbuf(&trace_packet, &out);
 	strbuf_release(&out);
 }
 
 /*
- * Write a packetized stream, where each line is preceded by
- * its length (including the header) as a 4-byte hex number.
- * A length of 'zero' means end of stream (and a length of 1-3
- * would be an error).
- *
- * This is all pretty stupid, but we use this packetized line
- * format to make a streaming format possible without ever
- * over-running the read buffers. That way we'll never read
- * into what might be the pack data (which should go to another
- * process entirely).
- *
- * The writing side could use stdio, but since the reading
- * side can't, we stay with pure read/write interfaces.
- */
-ssize_t safe_write(int fd, const void *buf, ssize_t n)
-{
-	ssize_t nn = n;
-	while (n) {
-		int ret = xwrite(fd, buf, n);
-		if (ret > 0) {
-			buf = (char *) buf + ret;
-			n -= ret;
-			continue;
-		}
-		if (!ret)
-			die("write error (disk full?)");
-		die_errno("write error");
-	}
-	return nn;
-}
-
-/*
  * If we buffered things up above (we don't, but we should),
  * we'd flush it here
  */
 void packet_flush(int fd)
 {
 	packet_trace("0000", 4, 1);
-	safe_write(fd, "0000", 4);
+	write_or_die(fd, "0000", 4);
 }
 
 void packet_buf_flush(struct strbuf *buf)
@@ -95,53 +98,76 @@ void packet_buf_flush(struct strbuf *buf)
 }
 
 #define hex(a) (hexchar[(a) & 15])
-static char buffer[1000];
-static unsigned format_packet(const char *fmt, va_list args)
+static void format_packet(struct strbuf *out, const char *fmt, va_list args)
 {
 	static char hexchar[] = "0123456789abcdef";
-	unsigned n;
+	size_t orig_len, n;
+
+	orig_len = out->len;
+	strbuf_addstr(out, "0000");
+	strbuf_vaddf(out, fmt, args);
+	n = out->len - orig_len;
 
-	n = vsnprintf(buffer + 4, sizeof(buffer) - 4, fmt, args);
-	if (n >= sizeof(buffer)-4)
+	if (n > LARGE_PACKET_MAX)
 		die("protocol error: impossibly long line");
-	n += 4;
-	buffer[0] = hex(n >> 12);
-	buffer[1] = hex(n >> 8);
-	buffer[2] = hex(n >> 4);
-	buffer[3] = hex(n);
-	packet_trace(buffer+4, n-4, 1);
-	return n;
+
+	out->buf[orig_len + 0] = hex(n >> 12);
+	out->buf[orig_len + 1] = hex(n >> 8);
+	out->buf[orig_len + 2] = hex(n >> 4);
+	out->buf[orig_len + 3] = hex(n);
+	packet_trace(out->buf + orig_len + 4, n - 4, 1);
 }
 
 void packet_write(int fd, const char *fmt, ...)
 {
+	static struct strbuf buf = STRBUF_INIT;
 	va_list args;
-	unsigned n;
 
+	strbuf_reset(&buf);
 	va_start(args, fmt);
-	n = format_packet(fmt, args);
+	format_packet(&buf, fmt, args);
 	va_end(args);
-	safe_write(fd, buffer, n);
+	write_or_die(fd, buf.buf, buf.len);
 }
 
 void packet_buf_write(struct strbuf *buf, const char *fmt, ...)
 {
 	va_list args;
-	unsigned n;
 
 	va_start(args, fmt);
-	n = format_packet(fmt, args);
+	format_packet(buf, fmt, args);
 	va_end(args);
-	strbuf_add(buf, buffer, n);
 }
 
-static void safe_read(int fd, void *buffer, unsigned size)
+static int get_packet_data(int fd, char **src_buf, size_t *src_size,
+			   void *dst, unsigned size, int options)
 {
-	ssize_t ret = read_in_full(fd, buffer, size);
-	if (ret < 0)
-		die_errno("read error");
-	else if (ret < size)
+	ssize_t ret;
+
+	if (fd >= 0 && src_buf && *src_buf)
+		die("BUG: multiple sources given to packet_read");
+
+	/* Read up to "size" bytes from our source, whatever it is. */
+	if (src_buf && *src_buf) {
+		ret = size < *src_size ? size : *src_size;
+		memcpy(dst, *src_buf, ret);
+		*src_buf += ret;
+		*src_size -= ret;
+	} else {
+		ret = read_in_full(fd, dst, size);
+		if (ret < 0)
+			die_errno("read error");
+	}
+
+	/* And complain if we didn't get enough bytes to satisfy the read. */
+	if (ret < size) {
+		if (options & PACKET_READ_GENTLE_ON_EOF)
+			return -1;
+
 		die("The remote end hung up unexpectedly");
+	}
+
+	return ret;
 }
 
 static int packet_length(const char *linelen)
@@ -169,12 +195,15 @@ static int packet_length(const char *linelen)
 	return len;
 }
 
-int packet_read_line(int fd, char *buffer, unsigned size)
+int packet_read(int fd, char **src_buf, size_t *src_len,
+		char *buffer, unsigned size, int options)
 {
-	int len;
+	int len, ret;
 	char linelen[4];
 
-	safe_read(fd, linelen, 4);
+	ret = get_packet_data(fd, src_buf, src_len, linelen, 4, options);
+	if (ret < 0)
+		return ret;
 	len = packet_length(linelen);
 	if (len < 0)
 		die("protocol error: bad line length character: %.4s", linelen);
@@ -185,38 +214,37 @@ int packet_read_line(int fd, char *buffer, unsigned size)
 	len -= 4;
 	if (len >= size)
 		die("protocol error: bad line length %d", len);
-	safe_read(fd, buffer, len);
+	ret = get_packet_data(fd, src_buf, src_len, buffer, len, options);
+	if (ret < 0)
+		return ret;
+
+	if ((options & PACKET_READ_CHOMP_NEWLINE) &&
+	    len && buffer[len-1] == '\n')
+		len--;
+
 	buffer[len] = 0;
 	packet_trace(buffer, len, 0);
 	return len;
 }
 
-int packet_get_line(struct strbuf *out,
-	char **src_buf, size_t *src_len)
+static char *packet_read_line_generic(int fd,
+				      char **src, size_t *src_len,
+				      int *dst_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;
-		packet_trace("0000", 4, 0);
-		return 0;
-	}
-	if (*src_len < len)
-		return -2;
+	int len = packet_read(fd, src, src_len,
+			      packet_buffer, sizeof(packet_buffer),
+			      PACKET_READ_CHOMP_NEWLINE);
+	if (dst_len)
+		*dst_len = len;
+	return len ? packet_buffer : NULL;
+}
 
-	*src_buf += 4;
-	*src_len -= 4;
-	len -= 4;
+char *packet_read_line(int fd, int *len_p)
+{
+	return packet_read_line_generic(fd, NULL, NULL, len_p);
+}
 
-	strbuf_add(out, *src_buf, len);
-	*src_buf += len;
-	*src_len -= len;
-	packet_trace(out->buf, out->len, 0);
-	return len;
+char *packet_read_line_buf(char **src, size_t *src_len, int *dst_len)
+{
+	return packet_read_line_generic(-1, src, src_len, dst_len);
 }