[thirdparty/git.git] / pkt-line.c

#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 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 (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 ",
		    get_trace_prefix(), write ? '>' : '<');

	/* 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_packet, &out);
	strbuf_release(&out);
}

/*
 * 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);
	if (write_in_full(fd, "0000", 4) < 0)
		die_errno(_("unable to write flush packet"));
}

void packet_delim(int fd)
{
	packet_trace("0001", 4, 1);
	if (write_in_full(fd, "0001", 4) < 0)
		die_errno(_("unable to write delim packet"));
}

void packet_response_end(int fd)
{
	packet_trace("0002", 4, 1);
	if (write_in_full(fd, "0002", 4) < 0)
		die_errno(_("unable to write stateless separator packet"));
}

int packet_flush_gently(int fd)
{
	packet_trace("0000", 4, 1);
	if (write_in_full(fd, "0000", 4) < 0)
		return error(_("flush packet write failed"));
	return 0;
}

void packet_buf_flush(struct strbuf *buf)
{
	packet_trace("0000", 4, 1);
	strbuf_add(buf, "0000", 4);
}

void packet_buf_delim(struct strbuf *buf)
{
	packet_trace("0001", 4, 1);
	strbuf_add(buf, "0001", 4);
}

void set_packet_header(char *buf, int size)
{
	static char hexchar[] = "0123456789abcdef";

	#define hex(a) (hexchar[(a) & 15])
	buf[0] = hex(size >> 12);
	buf[1] = hex(size >> 8);
	buf[2] = hex(size >> 4);
	buf[3] = hex(size);
	#undef hex
}

static void format_packet(struct strbuf *out, const char *prefix,
			  const char *fmt, va_list args)
{
	size_t orig_len, n;

	orig_len = out->len;
	strbuf_addstr(out, "0000");
	strbuf_addstr(out, prefix);
	strbuf_vaddf(out, fmt, args);
	n = out->len - orig_len;

	if (n > LARGE_PACKET_MAX)
		die(_("protocol error: impossibly long line"));

	set_packet_header(&out->buf[orig_len], n);
	packet_trace(out->buf + orig_len + 4, n - 4, 1);
}

static int packet_write_fmt_1(int fd, int gently, const char *prefix,
			      const char *fmt, va_list args)
{
	static struct strbuf buf = STRBUF_INIT;

	strbuf_reset(&buf);
	format_packet(&buf, prefix, fmt, args);
	if (write_in_full(fd, buf.buf, buf.len) < 0) {
		if (!gently) {
			check_pipe(errno);
			die_errno(_("packet write with format failed"));
		}
		return error(_("packet write with format failed"));
	}

	return 0;
}

void packet_write_fmt(int fd, const char *fmt, ...)
{
	va_list args;

	va_start(args, fmt);
	packet_write_fmt_1(fd, 0, "", fmt, args);
	va_end(args);
}

int packet_write_fmt_gently(int fd, const char *fmt, ...)
{
	int status;
	va_list args;

	va_start(args, fmt);
	status = packet_write_fmt_1(fd, 1, "", fmt, args);
	va_end(args);
	return status;
}

static int packet_write_gently(const int fd_out, const char *buf, size_t size)
{
	char header[4];
	size_t packet_size;

	if (size > LARGE_PACKET_DATA_MAX)
		return error(_("packet write failed - data exceeds max packet size"));

	packet_trace(buf, size, 1);
	packet_size = size + 4;

	set_packet_header(header, packet_size);

	/*
	 * Write the header and the buffer in 2 parts so that we do
	 * not need to allocate a buffer or rely on a static buffer.
	 * This also avoids putting a large buffer on the stack which
	 * might have multi-threading issues.
	 */

	if (write_in_full(fd_out, header, 4) < 0 ||
	    write_in_full(fd_out, buf, size) < 0)
		return error(_("packet write failed"));
	return 0;
}

void packet_write(int fd_out, const char *buf, size_t size)
{
	if (packet_write_gently(fd_out, buf, size))
		die_errno(_("packet write failed"));
}

void packet_buf_write(struct strbuf *buf, const char *fmt, ...)
{
	va_list args;

	va_start(args, fmt);
	format_packet(buf, "", fmt, args);
	va_end(args);
}

void packet_buf_write_len(struct strbuf *buf, const char *data, size_t len)
{
	size_t orig_len, n;

	orig_len = buf->len;
	strbuf_addstr(buf, "0000");
	strbuf_add(buf, data, len);
	n = buf->len - orig_len;

	if (n > LARGE_PACKET_MAX)
		die(_("protocol error: impossibly long line"));

	set_packet_header(&buf->buf[orig_len], n);
	packet_trace(data, len, 1);
}

int write_packetized_from_fd_no_flush(int fd_in, int fd_out)
{
	char *buf = xmalloc(LARGE_PACKET_DATA_MAX);
	int err = 0;
	ssize_t bytes_to_write;

	while (!err) {
		bytes_to_write = xread(fd_in, buf, LARGE_PACKET_DATA_MAX);
		if (bytes_to_write < 0) {
			free(buf);
			return COPY_READ_ERROR;
		}
		if (bytes_to_write == 0)
			break;
		err = packet_write_gently(fd_out, buf, bytes_to_write);
	}
	free(buf);
	return err;
}

int write_packetized_from_buf_no_flush(const char *src_in, size_t len, int fd_out)
{
	int err = 0;
	size_t bytes_written = 0;
	size_t bytes_to_write;

	while (!err) {
		if ((len - bytes_written) > LARGE_PACKET_DATA_MAX)
			bytes_to_write = LARGE_PACKET_DATA_MAX;
		else
			bytes_to_write = len - bytes_written;
		if (bytes_to_write == 0)
			break;
		err = packet_write_gently(fd_out, src_in + bytes_written, bytes_to_write);
		bytes_written += bytes_to_write;
	}
	return err;
}

static int get_packet_data(int fd, char **src_buf, size_t *src_size,
			   void *dst, unsigned size, int options)
{
	ssize_t ret;

	if (fd >= 0 && src_buf && *src_buf)
		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) {
			if (options & PACKET_READ_GENTLE_ON_READ_ERROR)
				return error_errno(_("read error"));
			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;

		if (options & PACKET_READ_GENTLE_ON_READ_ERROR)
			return error(_("the remote end hung up unexpectedly"));
		die(_("the remote end hung up unexpectedly"));
	}

	return ret;
}

int packet_length(const char lenbuf_hex[4])
{
	int val = hex2chr(lenbuf_hex);
	return (val < 0) ? val : (val << 8) | hex2chr(lenbuf_hex + 2);
}

enum packet_read_status packet_read_with_status(int fd, char **src_buffer,
						size_t *src_len, char *buffer,
						unsigned size, int *pktlen,
						int options)
{
	int len;
	char linelen[4];

	if (get_packet_data(fd, src_buffer, src_len, linelen, 4, options) < 0) {
		*pktlen = -1;
		return PACKET_READ_EOF;
	}

	len = packet_length(linelen);

	if (len < 0) {
		if (options & PACKET_READ_GENTLE_ON_READ_ERROR)
			return error(_("protocol error: bad line length "
				       "character: %.4s"), linelen);
		die(_("protocol error: bad line length character: %.4s"), linelen);
	} else if (!len) {
		packet_trace("0000", 4, 0);
		*pktlen = 0;
		return PACKET_READ_FLUSH;
	} else if (len == 1) {
		packet_trace("0001", 4, 0);
		*pktlen = 0;
		return PACKET_READ_DELIM;
	} else if (len == 2) {
		packet_trace("0002", 4, 0);
		*pktlen = 0;
		return PACKET_READ_RESPONSE_END;
	} else if (len < 4) {
		if (options & PACKET_READ_GENTLE_ON_READ_ERROR)
			return error(_("protocol error: bad line length %d"),
				     len);
		die(_("protocol error: bad line length %d"), len);
	}

	len -= 4;
	if ((unsigned)len >= size) {
		if (options & PACKET_READ_GENTLE_ON_READ_ERROR)
			return error(_("protocol error: bad line length %d"),
				     len);
		die(_("protocol error: bad line length %d"), len);
	}

	if (get_packet_data(fd, src_buffer, src_len, buffer, len, options) < 0) {
		*pktlen = -1;
		return PACKET_READ_EOF;
	}

	if ((options & PACKET_READ_CHOMP_NEWLINE) &&
	    len && buffer[len-1] == '\n')
		len--;

	buffer[len] = 0;
	packet_trace(buffer, len, 0);

	if ((options & PACKET_READ_DIE_ON_ERR_PACKET) &&
	    starts_with(buffer, "ERR "))
		die(_("remote error: %s"), buffer + 4);

	*pktlen = len;
	return PACKET_READ_NORMAL;
}

int packet_read(int fd, char **src_buffer, size_t *src_len,
		char *buffer, unsigned size, int options)
{
	int pktlen = -1;

	packet_read_with_status(fd, src_buffer, src_len, buffer, size,
				&pktlen, options);

	return pktlen;
}

static char *packet_read_line_generic(int fd,
				      char **src, size_t *src_len,
				      int *dst_len)
{
	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 > 0) ? packet_buffer : NULL;
}

char *packet_read_line(int fd, int *len_p)
{
	return packet_read_line_generic(fd, NULL, NULL, len_p);
}

int packet_read_line_gently(int fd, int *dst_len, char **dst_line)
{
	int len = packet_read(fd, NULL, NULL,
			      packet_buffer, sizeof(packet_buffer),
			      PACKET_READ_CHOMP_NEWLINE|PACKET_READ_GENTLE_ON_EOF);
	if (dst_len)
		*dst_len = len;
	if (dst_line)
		*dst_line = (len > 0) ? packet_buffer : NULL;
	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);
}

ssize_t read_packetized_to_strbuf(int fd_in, struct strbuf *sb_out, int options)
{
	int packet_len;

	size_t orig_len = sb_out->len;
	size_t orig_alloc = sb_out->alloc;

	for (;;) {
		strbuf_grow(sb_out, LARGE_PACKET_DATA_MAX);
		packet_len = packet_read(fd_in, NULL, NULL,
			/* strbuf_grow() above always allocates one extra byte to
			 * store a '\0' at the end of the string. packet_read()
			 * writes a '\0' extra byte at the end, too. Let it know
			 * that there is already room for the extra byte.
			 */
			sb_out->buf + sb_out->len, LARGE_PACKET_DATA_MAX+1,
			options);
		if (packet_len <= 0)
			break;
		sb_out->len += packet_len;
	}

	if (packet_len < 0) {
		if (orig_alloc == 0)
			strbuf_release(sb_out);
		else
			strbuf_setlen(sb_out, orig_len);
		return packet_len;
	}
	return sb_out->len - orig_len;
}

int recv_sideband(const char *me, int in_stream, int out)
{
	char buf[LARGE_PACKET_MAX + 1];
	int len;
	struct strbuf scratch = STRBUF_INIT;
	enum sideband_type sideband_type;

	while (1) {
		int status = packet_read_with_status(in_stream, NULL, NULL,
						     buf, LARGE_PACKET_MAX,
						     &len,
						     PACKET_READ_GENTLE_ON_EOF);
		if (!demultiplex_sideband(me, status, buf, len, 0, &scratch,
					  &sideband_type))
			continue;
		switch (sideband_type) {
		case SIDEBAND_PRIMARY:
			write_or_die(out, buf + 1, len - 1);
			break;
		default: /* errors: message already written */
			if (scratch.len > 0)
				BUG("unhandled incomplete sideband: '%s'",
				    scratch.buf);
			return sideband_type;
		}
	}
}

/* Packet Reader Functions */
void packet_reader_init(struct packet_reader *reader, int fd,
			char *src_buffer, size_t src_len,
			int options)
{
	memset(reader, 0, sizeof(*reader));

	reader->fd = fd;
	reader->src_buffer = src_buffer;
	reader->src_len = src_len;
	reader->buffer = packet_buffer;
	reader->buffer_size = sizeof(packet_buffer);
	reader->options = options;
	reader->me = "git";
	reader->hash_algo = &hash_algos[GIT_HASH_SHA1];
}

enum packet_read_status packet_reader_read(struct packet_reader *reader)
{
	struct strbuf scratch = STRBUF_INIT;

	if (reader->line_peeked) {
		reader->line_peeked = 0;
		return reader->status;
	}

	/*
	 * Consume all progress packets until a primary payload packet is
	 * received
	 */
	while (1) {
		enum sideband_type sideband_type;
		reader->status = packet_read_with_status(reader->fd,
							 &reader->src_buffer,
							 &reader->src_len,
							 reader->buffer,
							 reader->buffer_size,
							 &reader->pktlen,
							 reader->options);
		if (!reader->use_sideband)
			break;
		if (demultiplex_sideband(reader->me, reader->status,
					 reader->buffer, reader->pktlen, 1,
					 &scratch, &sideband_type))
			break;
	}

	if (reader->status == PACKET_READ_NORMAL)
		/* Skip the sideband designator if sideband is used */
		reader->line = reader->use_sideband ?
			reader->buffer + 1 : reader->buffer;
	else
		reader->line = NULL;

	return reader->status;
}

enum packet_read_status packet_reader_peek(struct packet_reader *reader)
{
	/* Only allow peeking a single line */
	if (reader->line_peeked)
		return reader->status;

	/* Peek a line by reading it and setting peeked flag */
	packet_reader_read(reader);
	reader->line_peeked = 1;
	return reader->status;
}

void packet_writer_init(struct packet_writer *writer, int dest_fd)
{
	writer->dest_fd = dest_fd;
	writer->use_sideband = 0;
}

void packet_writer_write(struct packet_writer *writer, const char *fmt, ...)
{
	va_list args;

	va_start(args, fmt);
	packet_write_fmt_1(writer->dest_fd, 0,
			   writer->use_sideband ? "\001" : "", fmt, args);
	va_end(args);
}

void packet_writer_error(struct packet_writer *writer, const char *fmt, ...)
{
	va_list args;

	va_start(args, fmt);
	packet_write_fmt_1(writer->dest_fd, 0,
			   writer->use_sideband ? "\003" : "ERR ", fmt, args);
	va_end(args);
}

void packet_writer_delim(struct packet_writer *writer)
{
	packet_delim(writer->dest_fd);
}

void packet_writer_flush(struct packet_writer *writer)
{
	packet_flush(writer->dest_fd);
}
Commit	Line	Data
f3a3214e LT	1	#include "cache.h"
f3a3214e LT	2	#include "pkt-line.h"
fd89433d	3	#include "run-command.h"
f3a3214e	4
74543a04	5	char packet_buffer[LARGE_PACKET_MAX];
1e4cd68c	6	static const char *packet_trace_prefix = "git";
6aa30857	7	static struct trace_key trace_packet = TRACE_KEY_INIT(PACKET);
32359838	8	static struct trace_key trace_pack = TRACE_KEY_INIT(PACKFILE);
bbc30f99 JK	9
	10	void packet_trace_identity(const char *prog)
	11	{
	12	packet_trace_prefix = xstrdup(prog);
	13	}
	14
fd89433d JK	15	static const char *get_trace_prefix(void)
	16	{
	17	return in_async() ? "sideband" : packet_trace_prefix;
	18	}
	19
32359838 JK	20	static int packet_trace_pack(const char *buf, unsigned int len, int sideband)
	21	{
	22	if (!sideband) {
	23	trace_verbatim(&trace_pack, buf, len);
	24	return 1;
	25	} else if (len && *buf == '\1') {
	26	trace_verbatim(&trace_pack, buf + 1, len - 1);
	27	return 1;
	28	} else {
	29	/* it's another non-pack sideband */
	30	return 0;
	31	}
	32	}
	33
bbc30f99 JK	34	static void packet_trace(const char *buf, unsigned int len, int write)
	35	{
	36	int i;
	37	struct strbuf out;
32359838 JK	38	static int in_pack, sideband;
	39
	40	if (!trace_want(&trace_packet) && !trace_want(&trace_pack))
	41	return;
	42
	43	if (in_pack) {
	44	if (packet_trace_pack(buf, len, sideband))
	45	return;
	46	} else if (starts_with(buf, "PACK") \|\| starts_with(buf, "\1PACK")) {
	47	in_pack = 1;
	48	sideband = *buf == '\1';
	49	packet_trace_pack(buf, len, sideband);
	50
	51	/*
	52	* Make a note in the human-readable trace that the pack data
	53	* started.
	54	*/
	55	buf = "PACK ...";
	56	len = strlen(buf);
	57	}
bbc30f99	58
6aa30857	59	if (!trace_want(&trace_packet))
bbc30f99 JK	60	return;
	61
	62	/* +32 is just a guess for header + quoting */
	63	strbuf_init(&out, len+32);
	64
	65	strbuf_addf(&out, "packet: %12s%c ",
fd89433d	66	get_trace_prefix(), write ? '>' : '<');
bbc30f99	67
32359838 JK	68	/* XXX we should really handle printable utf8 */
	69	for (i = 0; i < len; i++) {
	70	/* suppress newlines */
	71	if (buf[i] == '\n')
	72	continue;
	73	if (buf[i] >= 0x20 && buf[i] <= 0x7e)
	74	strbuf_addch(&out, buf[i]);
	75	else
	76	strbuf_addf(&out, "\\%o", buf[i]);
bbc30f99 JK	77	}
	78
	79	strbuf_addch(&out, '\n');
6aa30857	80	trace_strbuf(&trace_packet, &out);
bbc30f99 JK	81	strbuf_release(&out);
	82	}
	83
f3a3214e LT	84	/*
	85	* If we buffered things up above (we don't, but we should),
	86	* we'd flush it here
	87	*/
	88	void packet_flush(int fd)
	89	{
bbc30f99	90	packet_trace("0000", 4, 1);
37c80012 JK	91	if (write_in_full(fd, "0000", 4) < 0)
37c80012 JK	92	die_errno(_("unable to write flush packet"));
f3a3214e LT	93	}
f3a3214e LT	94
a4cfd41c BW	95	void packet_delim(int fd)
	96	{
	97	packet_trace("0001", 4, 1);
37c80012 JK	98	if (write_in_full(fd, "0001", 4) < 0)
37c80012 JK	99	die_errno(_("unable to write delim packet"));
a4cfd41c BW	100	}
a4cfd41c BW	101
0181b600 DL	102	void packet_response_end(int fd)
	103	{
	104	packet_trace("0002", 4, 1);
	105	if (write_in_full(fd, "0002", 4) < 0)
	106	die_errno(_("unable to write stateless separator packet"));
	107	}
	108
038ce90f LS	109	int packet_flush_gently(int fd)
	110	{
	111	packet_trace("0000", 4, 1);
4c95e3dd	112	if (write_in_full(fd, "0000", 4) < 0)
c60d7697	113	return error(_("flush packet write failed"));
4c95e3dd	114	return 0;
038ce90f LS	115	}
038ce90f LS	116
f5615d24 SP	117	void packet_buf_flush(struct strbuf *buf)
f5615d24 SP	118	{
bbc30f99	119	packet_trace("0000", 4, 1);
f5615d24 SP	120	strbuf_add(buf, "0000", 4);
	121	}
	122
a4cfd41c BW	123	void packet_buf_delim(struct strbuf *buf)
	124	{
	125	packet_trace("0001", 4, 1);
	126	strbuf_add(buf, "0001", 4);
	127	}
	128
56bea280	129	void set_packet_header(char *buf, int size)
f3a3214e	130	{
f3a3214e	131	static char hexchar[] = "0123456789abcdef";
2f60bdd1 LS	132
	133	#define hex(a) (hexchar[(a) & 15])
	134	buf[0] = hex(size >> 12);
	135	buf[1] = hex(size >> 8);
	136	buf[2] = hex(size >> 4);
	137	buf[3] = hex(size);
	138	#undef hex
	139	}
	140
bc2e795c JT	141	static void format_packet(struct strbuf out, const char prefix,
bc2e795c JT	142	const char *fmt, va_list args)
2f60bdd1	143	{
8e9faf27	144	size_t orig_len, n;
f3a3214e	145
8e9faf27 JK	146	orig_len = out->len;
8e9faf27 JK	147	strbuf_addstr(out, "0000");
bc2e795c	148	strbuf_addstr(out, prefix);
8e9faf27 JK	149	strbuf_vaddf(out, fmt, args);
	150	n = out->len - orig_len;
	151
	152	if (n > LARGE_PACKET_MAX)
c60d7697	153	die(_("protocol error: impossibly long line"));
8e9faf27	154
2f60bdd1	155	set_packet_header(&out->buf[orig_len], n);
8e9faf27	156	packet_trace(out->buf + orig_len + 4, n - 4, 1);
f5615d24 SP	157	}
f5615d24 SP	158
bc2e795c	159	static int packet_write_fmt_1(int fd, int gently, const char *prefix,
70428d1a LS	160	const char *fmt, va_list args)
70428d1a LS	161	{
150efef1	162	static struct strbuf buf = STRBUF_INIT;
70428d1a	163
150efef1	164	strbuf_reset(&buf);
bc2e795c	165	format_packet(&buf, prefix, fmt, args);
4c95e3dd JK	166	if (write_in_full(fd, buf.buf, buf.len) < 0) {
	167	if (!gently) {
	168	check_pipe(errno);
c60d7697	169	die_errno(_("packet write with format failed"));
4c95e3dd	170	}
c60d7697	171	return error(_("packet write with format failed"));
70428d1a	172	}
4c95e3dd JK	173
4c95e3dd JK	174	return 0;
70428d1a LS	175	}
70428d1a LS	176
81c634e9	177	void packet_write_fmt(int fd, const char *fmt, ...)
f5615d24 SP	178	{
f5615d24 SP	179	va_list args;
f5615d24 SP	180
f5615d24 SP	181	va_start(args, fmt);
bc2e795c	182	packet_write_fmt_1(fd, 0, "", fmt, args);
70428d1a LS	183	va_end(args);
	184	}
	185
	186	int packet_write_fmt_gently(int fd, const char *fmt, ...)
	187	{
	188	int status;
	189	va_list args;
	190
	191	va_start(args, fmt);
bc2e795c	192	status = packet_write_fmt_1(fd, 1, "", fmt, args);
f5615d24	193	va_end(args);
70428d1a	194	return status;
f3a3214e LT	195	}
f3a3214e LT	196
edfb780c LS	197	static int packet_write_gently(const int fd_out, const char *buf, size_t size)
edfb780c LS	198	{
7455e05e	199	char header[4];
edfb780c LS	200	size_t packet_size;
edfb780c LS	201
7455e05e	202	if (size > LARGE_PACKET_DATA_MAX)
c60d7697	203	return error(_("packet write failed - data exceeds max packet size"));
edfb780c LS	204
	205	packet_trace(buf, size, 1);
	206	packet_size = size + 4;
7455e05e JH	207
	208	set_packet_header(header, packet_size);
	209
	210	/*
	211	* Write the header and the buffer in 2 parts so that we do
	212	* not need to allocate a buffer or rely on a static buffer.
	213	* This also avoids putting a large buffer on the stack which
	214	* might have multi-threading issues.
	215	*/
	216
	217	if (write_in_full(fd_out, header, 4) < 0 \|\|
	218	write_in_full(fd_out, buf, size) < 0)
c60d7697	219	return error(_("packet write failed"));
4c95e3dd	220	return 0;
edfb780c LS	221	}
edfb780c LS	222
5d2124b3 BW	223	void packet_write(int fd_out, const char *buf, size_t size)
	224	{
	225	if (packet_write_gently(fd_out, buf, size))
c60d7697	226	die_errno(_("packet write failed"));
5d2124b3 BW	227	}
5d2124b3 BW	228
f5615d24 SP	229	void packet_buf_write(struct strbuf buf, const char fmt, ...)
	230	{
	231	va_list args;
f5615d24 SP	232
f5615d24 SP	233	va_start(args, fmt);
bc2e795c	234	format_packet(buf, "", fmt, args);
f5615d24	235	va_end(args);
f5615d24 SP	236	}
f5615d24 SP	237
f1f4d8ac BW	238	void packet_buf_write_len(struct strbuf buf, const char data, size_t len)
	239	{
	240	size_t orig_len, n;
	241
	242	orig_len = buf->len;
	243	strbuf_addstr(buf, "0000");
	244	strbuf_add(buf, data, len);
	245	n = buf->len - orig_len;
	246
	247	if (n > LARGE_PACKET_MAX)
c60d7697	248	die(_("protocol error: impossibly long line"));
f1f4d8ac BW	249
	250	set_packet_header(&buf->buf[orig_len], n);
	251	packet_trace(data, len, 1);
	252	}
	253
3a63c6a4	254	int write_packetized_from_fd_no_flush(int fd_in, int fd_out)
bb643d8b	255	{
7455e05e	256	char *buf = xmalloc(LARGE_PACKET_DATA_MAX);
bb643d8b LS	257	int err = 0;
	258	ssize_t bytes_to_write;
	259
	260	while (!err) {
7455e05e JH	261	bytes_to_write = xread(fd_in, buf, LARGE_PACKET_DATA_MAX);
	262	if (bytes_to_write < 0) {
	263	free(buf);
bb643d8b	264	return COPY_READ_ERROR;
7455e05e	265	}
bb643d8b LS	266	if (bytes_to_write == 0)
	267	break;
	268	err = packet_write_gently(fd_out, buf, bytes_to_write);
	269	}
7455e05e	270	free(buf);
bb643d8b LS	271	return err;
	272	}
	273
3a63c6a4	274	int write_packetized_from_buf_no_flush(const char *src_in, size_t len, int fd_out)
bb643d8b LS	275	{
	276	int err = 0;
	277	size_t bytes_written = 0;
	278	size_t bytes_to_write;
	279
	280	while (!err) {
	281	if ((len - bytes_written) > LARGE_PACKET_DATA_MAX)
	282	bytes_to_write = LARGE_PACKET_DATA_MAX;
	283	else
	284	bytes_to_write = len - bytes_written;
	285	if (bytes_to_write == 0)
	286	break;
	287	err = packet_write_gently(fd_out, src_in + bytes_written, bytes_to_write);
	288	bytes_written += bytes_to_write;
	289	}
bb643d8b LS	290	return err;
	291	}
	292
4981fe75 JK	293	static int get_packet_data(int fd, char *src_buf, size_t src_size,
4981fe75 JK	294	void *dst, unsigned size, int options)
f3a3214e	295	{
4981fe75 JK	296	ssize_t ret;
	297
	298	if (fd >= 0 && src_buf && *src_buf)
033abf97	299	BUG("multiple sources given to packet_read");
4981fe75 JK	300
	301	/* Read up to "size" bytes from our source, whatever it is. */
	302	if (src_buf && *src_buf) {
	303	ret = size < src_size ? size : src_size;
	304	memcpy(dst, *src_buf, ret);
	305	*src_buf += ret;
	306	*src_size -= ret;
	307	} else {
	308	ret = read_in_full(fd, dst, size);
c4ba5793 JS	309	if (ret < 0) {
	310	if (options & PACKET_READ_GENTLE_ON_READ_ERROR)
	311	return error_errno(_("read error"));
c60d7697	312	die_errno(_("read error"));
c4ba5793	313	}
4981fe75 JK	314	}
	315
	316	/* And complain if we didn't get enough bytes to satisfy the read. */
61d36330	317	if (ret != size) {
03809429	318	if (options & PACKET_READ_GENTLE_ON_EOF)
46284dd1 HV	319	return -1;
46284dd1 HV	320
c4ba5793 JS	321	if (options & PACKET_READ_GENTLE_ON_READ_ERROR)
c4ba5793 JS	322	return error(_("the remote end hung up unexpectedly"));
c60d7697	323	die(_("the remote end hung up unexpectedly"));
46284dd1 HV	324	}
	325
	326	return ret;
f3a3214e LT	327	}
f3a3214e LT	328
101736a1	329	int packet_length(const char lenbuf_hex[4])
f3a3214e	330	{
101736a1 DL	331	int val = hex2chr(lenbuf_hex);
101736a1 DL	332	return (val < 0) ? val : (val << 8) \| hex2chr(lenbuf_hex + 2);
f5615d24 SP	333	}
f5615d24 SP	334
2153d478 BW	335	enum packet_read_status packet_read_with_status(int fd, char **src_buffer,
	336	size_t src_len, char buffer,
	337	unsigned size, int *pktlen,
	338	int options)
f5615d24	339	{
2153d478	340	int len;
f5615d24 SP	341	char linelen[4];
f5615d24 SP	342
2153d478 BW	343	if (get_packet_data(fd, src_buffer, src_len, linelen, 4, options) < 0) {
	344	*pktlen = -1;
	345	return PACKET_READ_EOF;
	346	}
	347
f5615d24	348	len = packet_length(linelen);
2153d478 BW	349
2153d478 BW	350	if (len < 0) {
c4ba5793 JS	351	if (options & PACKET_READ_GENTLE_ON_READ_ERROR)
	352	return error(_("protocol error: bad line length "
	353	"character: %.4s"), linelen);
c60d7697	354	die(_("protocol error: bad line length character: %.4s"), linelen);
2153d478	355	} else if (!len) {
bbc30f99	356	packet_trace("0000", 4, 0);
2153d478 BW	357	*pktlen = 0;
2153d478 BW	358	return PACKET_READ_FLUSH;
a4cfd41c BW	359	} else if (len == 1) {
	360	packet_trace("0001", 4, 0);
	361	*pktlen = 0;
	362	return PACKET_READ_DELIM;
0181b600 DL	363	} else if (len == 2) {
	364	packet_trace("0002", 4, 0);
	365	*pktlen = 0;
	366	return PACKET_READ_RESPONSE_END;
2153d478	367	} else if (len < 4) {
c4ba5793 JS	368	if (options & PACKET_READ_GENTLE_ON_READ_ERROR)
	369	return error(_("protocol error: bad line length %d"),
	370	len);
c60d7697	371	die(_("protocol error: bad line length %d"), len);
bbc30f99	372	}
2153d478	373
f3a3214e	374	len -= 4;
c4ba5793 JS	375	if ((unsigned)len >= size) {
	376	if (options & PACKET_READ_GENTLE_ON_READ_ERROR)
	377	return error(_("protocol error: bad line length %d"),
	378	len);
c60d7697	379	die(_("protocol error: bad line length %d"), len);
c4ba5793	380	}
2153d478 BW	381
	382	if (get_packet_data(fd, src_buffer, src_len, buffer, len, options) < 0) {
	383	*pktlen = -1;
	384	return PACKET_READ_EOF;
	385	}
819b929d JK	386
	387	if ((options & PACKET_READ_CHOMP_NEWLINE) &&
	388	len && buffer[len-1] == '\n')
	389	len--;
	390
f3a3214e	391	buffer[len] = 0;
bbc30f99	392	packet_trace(buffer, len, 0);
533ddba4 JK	393
	394	if ((options & PACKET_READ_DIE_ON_ERR_PACKET) &&
	395	starts_with(buffer, "ERR "))
	396	die(_("remote error: %s"), buffer + 4);
	397
2153d478 BW	398	*pktlen = len;
	399	return PACKET_READ_NORMAL;
	400	}
	401
	402	int packet_read(int fd, char *src_buffer, size_t src_len,
	403	char *buffer, unsigned size, int options)
	404	{
	405	int pktlen = -1;
	406
	407	packet_read_with_status(fd, src_buffer, src_len, buffer, size,
	408	&pktlen, options);
	409
	410	return pktlen;
f3a3214e	411	}
f5615d24	412
4981fe75 JK	413	static char *packet_read_line_generic(int fd,
	414	char *src, size_t src_len,
	415	int *dst_len)
46284dd1	416	{
4981fe75 JK	417	int len = packet_read(fd, src, src_len,
4981fe75 JK	418	packet_buffer, sizeof(packet_buffer),
74543a04	419	PACKET_READ_CHOMP_NEWLINE);
4981fe75 JK	420	if (dst_len)
4981fe75 JK	421	*dst_len = len;
974b50c5	422	return (len > 0) ? packet_buffer : NULL;
46284dd1 HV	423	}
46284dd1 HV	424
4981fe75	425	char packet_read_line(int fd, int len_p)
f5615d24	426	{
4981fe75 JK	427	return packet_read_line_generic(fd, NULL, NULL, len_p);
4981fe75 JK	428	}
f5615d24	429
825b9226 BP	430	int packet_read_line_gently(int fd, int dst_len, char *dst_line)
	431	{
	432	int len = packet_read(fd, NULL, NULL,
	433	packet_buffer, sizeof(packet_buffer),
	434	PACKET_READ_CHOMP_NEWLINE\|PACKET_READ_GENTLE_ON_EOF);
	435	if (dst_len)
	436	*dst_len = len;
	437	if (dst_line)
	438	*dst_line = (len > 0) ? packet_buffer : NULL;
	439	return len;
	440	}
	441
4981fe75 JK	442	char packet_read_line_buf(char src, size_t src_len, int *dst_len)
	443	{
	444	return packet_read_line_generic(-1, src, src_len, dst_len);
f5615d24	445	}
bb643d8b	446
8c2efa5d	447	ssize_t read_packetized_to_strbuf(int fd_in, struct strbuf *sb_out, int options)
bb643d8b LS	448	{
	449	int packet_len;
	450
	451	size_t orig_len = sb_out->len;
	452	size_t orig_alloc = sb_out->alloc;
	453
	454	for (;;) {
	455	strbuf_grow(sb_out, LARGE_PACKET_DATA_MAX);
	456	packet_len = packet_read(fd_in, NULL, NULL,
	457	/* strbuf_grow() above always allocates one extra byte to
	458	* store a '\0' at the end of the string. packet_read()
	459	* writes a '\0' extra byte at the end, too. Let it know
	460	* that there is already room for the extra byte.
	461	*/
	462	sb_out->buf + sb_out->len, LARGE_PACKET_DATA_MAX+1,
8c2efa5d	463	options);
bb643d8b LS	464	if (packet_len <= 0)
	465	break;
	466	sb_out->len += packet_len;
	467	}
	468
	469	if (packet_len < 0) {
	470	if (orig_alloc == 0)
	471	strbuf_release(sb_out);
	472	else
	473	strbuf_setlen(sb_out, orig_len);
	474	return packet_len;
	475	}
	476	return sb_out->len - orig_len;
	477	}
77dabc14	478
fbd76cd4 JT	479	int recv_sideband(const char *me, int in_stream, int out)
	480	{
	481	char buf[LARGE_PACKET_MAX + 1];
	482	int len;
	483	struct strbuf scratch = STRBUF_INIT;
	484	enum sideband_type sideband_type;
	485
	486	while (1) {
af22a63c JK	487	int status = packet_read_with_status(in_stream, NULL, NULL,
	488	buf, LARGE_PACKET_MAX,
	489	&len,
	490	PACKET_READ_GENTLE_ON_EOF);
	491	if (!demultiplex_sideband(me, status, buf, len, 0, &scratch,
fbd76cd4 JT	492	&sideband_type))
	493	continue;
	494	switch (sideband_type) {
	495	case SIDEBAND_PRIMARY:
	496	write_or_die(out, buf + 1, len - 1);
	497	break;
	498	default: /* errors: message already written */
8e86cf65 JS	499	if (scratch.len > 0)
	500	BUG("unhandled incomplete sideband: '%s'",
	501	scratch.buf);
fbd76cd4 JT	502	return sideband_type;
	503	}
	504	}
	505	}
	506
77dabc14 BW	507	/* Packet Reader Functions */
	508	void packet_reader_init(struct packet_reader *reader, int fd,
	509	char *src_buffer, size_t src_len,
	510	int options)
	511	{
	512	memset(reader, 0, sizeof(*reader));
	513
	514	reader->fd = fd;
	515	reader->src_buffer = src_buffer;
	516	reader->src_len = src_len;
	517	reader->buffer = packet_buffer;
	518	reader->buffer_size = sizeof(packet_buffer);
	519	reader->options = options;
0bbc0bc5	520	reader->me = "git";
9a9f0d3f	521	reader->hash_algo = &hash_algos[GIT_HASH_SHA1];
77dabc14 BW	522	}
	523
	524	enum packet_read_status packet_reader_read(struct packet_reader *reader)
	525	{
0bbc0bc5 JT	526	struct strbuf scratch = STRBUF_INIT;
0bbc0bc5 JT	527
77dabc14 BW	528	if (reader->line_peeked) {
	529	reader->line_peeked = 0;
	530	return reader->status;
	531	}
	532
0bbc0bc5 JT	533	/*
	534	* Consume all progress packets until a primary payload packet is
	535	* received
	536	*/
	537	while (1) {
	538	enum sideband_type sideband_type;
	539	reader->status = packet_read_with_status(reader->fd,
	540	&reader->src_buffer,
	541	&reader->src_len,
	542	reader->buffer,
	543	reader->buffer_size,
	544	&reader->pktlen,
	545	reader->options);
	546	if (!reader->use_sideband)
	547	break;
af22a63c JK	548	if (demultiplex_sideband(reader->me, reader->status,
	549	reader->buffer, reader->pktlen, 1,
	550	&scratch, &sideband_type))
0bbc0bc5 JT	551	break;
0bbc0bc5 JT	552	}
77dabc14 BW	553
77dabc14 BW	554	if (reader->status == PACKET_READ_NORMAL)
0bbc0bc5 JT	555	/* Skip the sideband designator if sideband is used */
	556	reader->line = reader->use_sideband ?
	557	reader->buffer + 1 : reader->buffer;
77dabc14 BW	558	else
	559	reader->line = NULL;
	560
	561	return reader->status;
	562	}
	563
	564	enum packet_read_status packet_reader_peek(struct packet_reader *reader)
	565	{
	566	/* Only allow peeking a single line */
	567	if (reader->line_peeked)
	568	return reader->status;
	569
	570	/* Peek a line by reading it and setting peeked flag */
	571	packet_reader_read(reader);
	572	reader->line_peeked = 1;
	573	return reader->status;
	574	}
bc2e795c JT	575
	576	void packet_writer_init(struct packet_writer *writer, int dest_fd)
	577	{
	578	writer->dest_fd = dest_fd;
0bbc0bc5	579	writer->use_sideband = 0;
bc2e795c JT	580	}
	581
	582	void packet_writer_write(struct packet_writer writer, const char fmt, ...)
	583	{
	584	va_list args;
	585
	586	va_start(args, fmt);
0bbc0bc5 JT	587	packet_write_fmt_1(writer->dest_fd, 0,
0bbc0bc5 JT	588	writer->use_sideband ? "\001" : "", fmt, args);
bc2e795c JT	589	va_end(args);
	590	}
	591
	592	void packet_writer_error(struct packet_writer writer, const char fmt, ...)
	593	{
	594	va_list args;
	595
	596	va_start(args, fmt);
0bbc0bc5 JT	597	packet_write_fmt_1(writer->dest_fd, 0,
0bbc0bc5 JT	598	writer->use_sideband ? "\003" : "ERR ", fmt, args);
bc2e795c JT	599	va_end(args);
	600	}
	601
	602	void packet_writer_delim(struct packet_writer *writer)
	603	{
	604	packet_delim(writer->dest_fd);
	605	}
	606
	607	void packet_writer_flush(struct packet_writer *writer)
	608	{
	609	packet_flush(writer->dest_fd);
	610	}