[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);
	write_or_die(fd, "0000", 4);
}

void packet_delim(int fd)
{
	packet_trace("0001", 4, 1);
	write_or_die(fd, "0001", 4);
}

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);
}

static void set_packet_header(char *buf, const 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 *fmt, va_list args)
{
	size_t orig_len, n;

	orig_len = out->len;
	strbuf_addstr(out, "0000");
	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 *fmt, va_list args)
{
	static struct strbuf buf = STRBUF_INIT;

	strbuf_reset(&buf);
	format_packet(&buf, 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)
{
	static char packet_write_buffer[LARGE_PACKET_MAX];
	size_t packet_size;

	if (size > sizeof(packet_write_buffer) - 4)
		return error("packet write failed - data exceeds max packet size");

	packet_trace(buf, size, 1);
	packet_size = size + 4;
	set_packet_header(packet_write_buffer, packet_size);
	memcpy(packet_write_buffer + 4, buf, size);
	if (write_in_full(fd_out, packet_write_buffer, packet_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(int fd_in, int fd_out)
{
	static char buf[LARGE_PACKET_DATA_MAX];
	int err = 0;
	ssize_t bytes_to_write;

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

int write_packetized_from_buf(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;
	}
	if (!err)
		err = packet_flush_gently(fd_out);
	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)
			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)
{
	int val = hex2chr(linelen);
	return (val < 0) ? val : (val << 8) | hex2chr(linelen + 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) {
		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 < 4) {
		die("protocol error: bad line length %d", len);
	}

	len -= 4;
	if ((unsigned)len >= size)
		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);
	*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 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,
			PACKET_READ_GENTLE_ON_EOF);
		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;
}

/* 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;
}

enum packet_read_status packet_reader_read(struct packet_reader *reader)
{
	if (reader->line_peeked) {
		reader->line_peeked = 0;
		return reader->status;
	}

	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->status == PACKET_READ_NORMAL)
		reader->line = 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;
}
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);
cdf4fb8e	91	write_or_die(fd, "0000", 4);
f3a3214e LT	92	}
f3a3214e LT	93
a4cfd41c BW	94	void packet_delim(int fd)
	95	{
	96	packet_trace("0001", 4, 1);
	97	write_or_die(fd, "0001", 4);
	98	}
	99
038ce90f LS	100	int packet_flush_gently(int fd)
	101	{
	102	packet_trace("0000", 4, 1);
4c95e3dd JK	103	if (write_in_full(fd, "0000", 4) < 0)
	104	return error("flush packet write failed");
	105	return 0;
038ce90f LS	106	}
038ce90f LS	107
f5615d24 SP	108	void packet_buf_flush(struct strbuf *buf)
f5615d24 SP	109	{
bbc30f99	110	packet_trace("0000", 4, 1);
f5615d24 SP	111	strbuf_add(buf, "0000", 4);
	112	}
	113
a4cfd41c BW	114	void packet_buf_delim(struct strbuf *buf)
	115	{
	116	packet_trace("0001", 4, 1);
	117	strbuf_add(buf, "0001", 4);
	118	}
	119
2f60bdd1	120	static void set_packet_header(char *buf, const int size)
f3a3214e	121	{
f3a3214e	122	static char hexchar[] = "0123456789abcdef";
2f60bdd1 LS	123
	124	#define hex(a) (hexchar[(a) & 15])
	125	buf[0] = hex(size >> 12);
	126	buf[1] = hex(size >> 8);
	127	buf[2] = hex(size >> 4);
	128	buf[3] = hex(size);
	129	#undef hex
	130	}
	131
	132	static void format_packet(struct strbuf out, const char fmt, va_list args)
	133	{
8e9faf27	134	size_t orig_len, n;
f3a3214e	135
8e9faf27 JK	136	orig_len = out->len;
	137	strbuf_addstr(out, "0000");
	138	strbuf_vaddf(out, fmt, args);
	139	n = out->len - orig_len;
	140
	141	if (n > LARGE_PACKET_MAX)
f3a3214e	142	die("protocol error: impossibly long line");
8e9faf27	143
2f60bdd1	144	set_packet_header(&out->buf[orig_len], n);
8e9faf27	145	packet_trace(out->buf + orig_len + 4, n - 4, 1);
f5615d24 SP	146	}
f5615d24 SP	147
70428d1a LS	148	static int packet_write_fmt_1(int fd, int gently,
	149	const char *fmt, va_list args)
	150	{
150efef1	151	static struct strbuf buf = STRBUF_INIT;
70428d1a	152
150efef1	153	strbuf_reset(&buf);
70428d1a	154	format_packet(&buf, fmt, args);
4c95e3dd JK	155	if (write_in_full(fd, buf.buf, buf.len) < 0) {
	156	if (!gently) {
	157	check_pipe(errno);
	158	die_errno("packet write with format failed");
	159	}
	160	return error("packet write with format failed");
70428d1a	161	}
4c95e3dd JK	162
4c95e3dd JK	163	return 0;
70428d1a LS	164	}
70428d1a LS	165
81c634e9	166	void packet_write_fmt(int fd, const char *fmt, ...)
f5615d24 SP	167	{
f5615d24 SP	168	va_list args;
f5615d24 SP	169
f5615d24 SP	170	va_start(args, fmt);
70428d1a LS	171	packet_write_fmt_1(fd, 0, fmt, args);
	172	va_end(args);
	173	}
	174
	175	int packet_write_fmt_gently(int fd, const char *fmt, ...)
	176	{
	177	int status;
	178	va_list args;
	179
	180	va_start(args, fmt);
	181	status = packet_write_fmt_1(fd, 1, fmt, args);
f5615d24	182	va_end(args);
70428d1a	183	return status;
f3a3214e LT	184	}
f3a3214e LT	185
edfb780c LS	186	static int packet_write_gently(const int fd_out, const char *buf, size_t size)
	187	{
	188	static char packet_write_buffer[LARGE_PACKET_MAX];
	189	size_t packet_size;
	190
	191	if (size > sizeof(packet_write_buffer) - 4)
	192	return error("packet write failed - data exceeds max packet size");
	193
	194	packet_trace(buf, size, 1);
	195	packet_size = size + 4;
	196	set_packet_header(packet_write_buffer, packet_size);
	197	memcpy(packet_write_buffer + 4, buf, size);
4c95e3dd JK	198	if (write_in_full(fd_out, packet_write_buffer, packet_size) < 0)
	199	return error("packet write failed");
	200	return 0;
edfb780c LS	201	}
edfb780c LS	202
5d2124b3 BW	203	void packet_write(int fd_out, const char *buf, size_t size)
	204	{
	205	if (packet_write_gently(fd_out, buf, size))
	206	die_errno("packet write failed");
	207	}
	208
f5615d24 SP	209	void packet_buf_write(struct strbuf buf, const char fmt, ...)
	210	{
	211	va_list args;
f5615d24 SP	212
f5615d24 SP	213	va_start(args, fmt);
8e9faf27	214	format_packet(buf, fmt, args);
f5615d24	215	va_end(args);
f5615d24 SP	216	}
f5615d24 SP	217
f1f4d8ac BW	218	void packet_buf_write_len(struct strbuf buf, const char data, size_t len)
	219	{
	220	size_t orig_len, n;
	221
	222	orig_len = buf->len;
	223	strbuf_addstr(buf, "0000");
	224	strbuf_add(buf, data, len);
	225	n = buf->len - orig_len;
	226
	227	if (n > LARGE_PACKET_MAX)
	228	die("protocol error: impossibly long line");
	229
	230	set_packet_header(&buf->buf[orig_len], n);
	231	packet_trace(data, len, 1);
	232	}
	233
bb643d8b LS	234	int write_packetized_from_fd(int fd_in, int fd_out)
	235	{
	236	static char buf[LARGE_PACKET_DATA_MAX];
	237	int err = 0;
	238	ssize_t bytes_to_write;
	239
	240	while (!err) {
	241	bytes_to_write = xread(fd_in, buf, sizeof(buf));
	242	if (bytes_to_write < 0)
	243	return COPY_READ_ERROR;
	244	if (bytes_to_write == 0)
	245	break;
	246	err = packet_write_gently(fd_out, buf, bytes_to_write);
	247	}
	248	if (!err)
	249	err = packet_flush_gently(fd_out);
	250	return err;
	251	}
	252
	253	int write_packetized_from_buf(const char *src_in, size_t len, int fd_out)
	254	{
	255	int err = 0;
	256	size_t bytes_written = 0;
	257	size_t bytes_to_write;
	258
	259	while (!err) {
	260	if ((len - bytes_written) > LARGE_PACKET_DATA_MAX)
	261	bytes_to_write = LARGE_PACKET_DATA_MAX;
	262	else
	263	bytes_to_write = len - bytes_written;
	264	if (bytes_to_write == 0)
	265	break;
	266	err = packet_write_gently(fd_out, src_in + bytes_written, bytes_to_write);
	267	bytes_written += bytes_to_write;
	268	}
	269	if (!err)
	270	err = packet_flush_gently(fd_out);
	271	return err;
	272	}
	273
4981fe75 JK	274	static int get_packet_data(int fd, char *src_buf, size_t src_size,
4981fe75 JK	275	void *dst, unsigned size, int options)
f3a3214e	276	{
4981fe75 JK	277	ssize_t ret;
	278
	279	if (fd >= 0 && src_buf && *src_buf)
033abf97	280	BUG("multiple sources given to packet_read");
4981fe75 JK	281
	282	/* Read up to "size" bytes from our source, whatever it is. */
	283	if (src_buf && *src_buf) {
	284	ret = size < src_size ? size : src_size;
	285	memcpy(dst, *src_buf, ret);
	286	*src_buf += ret;
	287	*src_size -= ret;
	288	} else {
	289	ret = read_in_full(fd, dst, size);
	290	if (ret < 0)
	291	die_errno("read error");
	292	}
	293
	294	/* And complain if we didn't get enough bytes to satisfy the read. */
61d36330	295	if (ret != size) {
03809429	296	if (options & PACKET_READ_GENTLE_ON_EOF)
46284dd1 HV	297	return -1;
46284dd1 HV	298
c697ad14	299	die("The remote end hung up unexpectedly");
46284dd1 HV	300	}
	301
	302	return ret;
f3a3214e LT	303	}
f3a3214e LT	304
f5615d24	305	static int packet_length(const char *linelen)
f3a3214e	306	{
d2330973 RS	307	int val = hex2chr(linelen);
d2330973 RS	308	return (val < 0) ? val : (val << 8) \| hex2chr(linelen + 2);
f5615d24 SP	309	}
f5615d24 SP	310
2153d478 BW	311	enum packet_read_status packet_read_with_status(int fd, char **src_buffer,
	312	size_t src_len, char buffer,
	313	unsigned size, int *pktlen,
	314	int options)
f5615d24	315	{
2153d478	316	int len;
f5615d24 SP	317	char linelen[4];
f5615d24 SP	318
2153d478 BW	319	if (get_packet_data(fd, src_buffer, src_len, linelen, 4, options) < 0) {
	320	*pktlen = -1;
	321	return PACKET_READ_EOF;
	322	}
	323
f5615d24	324	len = packet_length(linelen);
2153d478 BW	325
2153d478 BW	326	if (len < 0) {
743c4b7b	327	die("protocol error: bad line length character: %.4s", linelen);
2153d478	328	} else if (!len) {
bbc30f99	329	packet_trace("0000", 4, 0);
2153d478 BW	330	*pktlen = 0;
2153d478 BW	331	return PACKET_READ_FLUSH;
a4cfd41c BW	332	} else if (len == 1) {
	333	packet_trace("0001", 4, 0);
	334	*pktlen = 0;
	335	return PACKET_READ_DELIM;
2153d478 BW	336	} else if (len < 4) {
2153d478 BW	337	die("protocol error: bad line length %d", len);
bbc30f99	338	}
2153d478	339
f3a3214e	340	len -= 4;
2153d478	341	if ((unsigned)len >= size)
f3a3214e	342	die("protocol error: bad line length %d", len);
2153d478 BW	343
	344	if (get_packet_data(fd, src_buffer, src_len, buffer, len, options) < 0) {
	345	*pktlen = -1;
	346	return PACKET_READ_EOF;
	347	}
819b929d JK	348
	349	if ((options & PACKET_READ_CHOMP_NEWLINE) &&
	350	len && buffer[len-1] == '\n')
	351	len--;
	352
f3a3214e	353	buffer[len] = 0;
bbc30f99	354	packet_trace(buffer, len, 0);
2153d478 BW	355	*pktlen = len;
	356	return PACKET_READ_NORMAL;
	357	}
	358
	359	int packet_read(int fd, char *src_buffer, size_t src_len,
	360	char *buffer, unsigned size, int options)
	361	{
	362	int pktlen = -1;
	363
	364	packet_read_with_status(fd, src_buffer, src_len, buffer, size,
	365	&pktlen, options);
	366
	367	return pktlen;
f3a3214e	368	}
f5615d24	369
4981fe75 JK	370	static char *packet_read_line_generic(int fd,
	371	char *src, size_t src_len,
	372	int *dst_len)
46284dd1	373	{
4981fe75 JK	374	int len = packet_read(fd, src, src_len,
4981fe75 JK	375	packet_buffer, sizeof(packet_buffer),
74543a04	376	PACKET_READ_CHOMP_NEWLINE);
4981fe75 JK	377	if (dst_len)
4981fe75 JK	378	*dst_len = len;
974b50c5	379	return (len > 0) ? packet_buffer : NULL;
46284dd1 HV	380	}
46284dd1 HV	381
4981fe75	382	char packet_read_line(int fd, int len_p)
f5615d24	383	{
4981fe75 JK	384	return packet_read_line_generic(fd, NULL, NULL, len_p);
4981fe75 JK	385	}
f5615d24	386
825b9226 BP	387	int packet_read_line_gently(int fd, int dst_len, char *dst_line)
	388	{
	389	int len = packet_read(fd, NULL, NULL,
	390	packet_buffer, sizeof(packet_buffer),
	391	PACKET_READ_CHOMP_NEWLINE\|PACKET_READ_GENTLE_ON_EOF);
	392	if (dst_len)
	393	*dst_len = len;
	394	if (dst_line)
	395	*dst_line = (len > 0) ? packet_buffer : NULL;
	396	return len;
	397	}
	398
4981fe75 JK	399	char packet_read_line_buf(char src, size_t src_len, int *dst_len)
	400	{
	401	return packet_read_line_generic(-1, src, src_len, dst_len);
f5615d24	402	}
bb643d8b LS	403
	404	ssize_t read_packetized_to_strbuf(int fd_in, struct strbuf *sb_out)
	405	{
	406	int packet_len;
	407
	408	size_t orig_len = sb_out->len;
	409	size_t orig_alloc = sb_out->alloc;
	410
	411	for (;;) {
	412	strbuf_grow(sb_out, LARGE_PACKET_DATA_MAX);
	413	packet_len = packet_read(fd_in, NULL, NULL,
	414	/* strbuf_grow() above always allocates one extra byte to
	415	* store a '\0' at the end of the string. packet_read()
	416	* writes a '\0' extra byte at the end, too. Let it know
	417	* that there is already room for the extra byte.
	418	*/
	419	sb_out->buf + sb_out->len, LARGE_PACKET_DATA_MAX+1,
	420	PACKET_READ_GENTLE_ON_EOF);
	421	if (packet_len <= 0)
	422	break;
	423	sb_out->len += packet_len;
	424	}
	425
	426	if (packet_len < 0) {
	427	if (orig_alloc == 0)
	428	strbuf_release(sb_out);
	429	else
	430	strbuf_setlen(sb_out, orig_len);
	431	return packet_len;
	432	}
	433	return sb_out->len - orig_len;
	434	}
77dabc14 BW	435
	436	/* Packet Reader Functions */
	437	void packet_reader_init(struct packet_reader *reader, int fd,
	438	char *src_buffer, size_t src_len,
	439	int options)
	440	{
	441	memset(reader, 0, sizeof(*reader));
	442
	443	reader->fd = fd;
	444	reader->src_buffer = src_buffer;
	445	reader->src_len = src_len;
	446	reader->buffer = packet_buffer;
	447	reader->buffer_size = sizeof(packet_buffer);
	448	reader->options = options;
	449	}
	450
	451	enum packet_read_status packet_reader_read(struct packet_reader *reader)
	452	{
	453	if (reader->line_peeked) {
	454	reader->line_peeked = 0;
	455	return reader->status;
	456	}
	457
	458	reader->status = packet_read_with_status(reader->fd,
	459	&reader->src_buffer,
	460	&reader->src_len,
	461	reader->buffer,
	462	reader->buffer_size,
	463	&reader->pktlen,
	464	reader->options);
	465
	466	if (reader->status == PACKET_READ_NORMAL)
	467	reader->line = reader->buffer;
	468	else
	469	reader->line = NULL;
	470
	471	return reader->status;
	472	}
	473
	474	enum packet_read_status packet_reader_peek(struct packet_reader *reader)
	475	{
	476	/* Only allow peeking a single line */
	477	if (reader->line_peeked)
	478	return reader->status;
	479
	480	/* Peek a line by reading it and setting peeked flag */
	481	packet_reader_read(reader);
	482	reader->line_peeked = 1;
	483	return reader->status;
	484	}