[rsync/rsync.git] / token.c

/* 
   Copyright (C) Andrew Tridgell 1996
   Copyright (C) Paul Mackerras 1996
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "rsync.h"
#include "lib/zlib.h"

extern int do_compression;


/* non-compressing recv token */
static int simple_recv_token(int f,char **data)
{
	static int residue;
	static char *buf;
	int n;

	if (!buf) {
		buf = (char *)malloc(CHUNK_SIZE);
		if (!buf) out_of_memory("simple_recv_token");
	}

	if (residue == 0) {
		int i = read_int(f);
		if (i <= 0) return i;
		residue = i;
	}

	*data = buf;
	n = MIN(CHUNK_SIZE,residue);
	residue -= n;
	read_buf(f,buf,n);
	return n;
}


/* non-compressing send token */
static void simple_send_token(int f,int token,
			      struct map_struct *buf,int offset,int n)
{
	if (n > 0) {
		int l = 0;
		while (l < n) {
			int n1 = MIN(CHUNK_SIZE,n-l);
			write_int(f,n1);
			write_buf(f,map_ptr(buf,offset+l,n1),n1);
			l += n1;
		}
	}
	write_int(f,-(token+1));
}


/* Memory allocation/freeing routines, called by zlib stuff. */
static void *
z_alloc(void *opaque, uInt items, uInt size)
{
    return malloc(items * size);
}

static void
z_free(void *opaque, void *adrs, uInt nbytes)
{
    free(adrs);
}

/* Flag bytes in compressed stream are encoded as follows: */
#define END_FLAG	0	/* that's all folks */
#define TOKEN_LONG	0x20	/* followed by 32-bit token number */
#define TOKENRUN_LONG	0x21	/* ditto with 16-bit run count */
#define DEFLATED_DATA	0x40	/* + 6-bit high len, then low len byte */
#define TOKEN_REL	0x80	/* + 6-bit relative token number */
#define TOKENRUN_REL	0xc0	/* ditto with 16-bit run count */

#define MAX_DATA_COUNT	16383	/* fit 14 bit count into 2 bytes with flags */

/* For coding runs of tokens */
static int last_token = -1;
static int run_start;
static int last_run_end;

/* Deflation state */
static z_stream tx_strm;

/* Output buffer */
static char *obuf;

/* Send a deflated token */
static void
send_deflated_token(int f, int token,
		    struct map_struct *buf, int offset, int nb, int toklen)
{
    int n, r;
    static int init_done;

    if (last_token == -1) {
	/* initialization */
	if (!init_done) {
	    tx_strm.next_in = NULL;
	    tx_strm.zalloc = z_alloc;
	    tx_strm.zfree = z_free;
	    if (deflateInit2(&tx_strm, Z_DEFAULT_COMPRESSION, 8,
			     -15, 8, Z_DEFAULT_STRATEGY) != Z_OK) {
		rprintf(FERROR, "compression init failed\n");
		exit_cleanup(1);
	    }
	    if ((obuf = malloc(MAX_DATA_COUNT+2)) == NULL)
		out_of_memory("send_deflated_token");
	    init_done = 1;
	} else
	    deflateReset(&tx_strm);
	run_start = token;
	last_run_end = 0;

    } else if (nb != 0 || token != last_token + 1
	       || token >= run_start + 65536) {
	/* output previous run */
	r = run_start - last_run_end;
	n = last_token - run_start;
	if (r >= 0 && r <= 63) {
	    write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
	} else {
	    write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
	    write_int(f, run_start);
	}
	if (n != 0) {
	    write_byte(f, n);
	    write_byte(f, n >> 8);
	}
	last_run_end = last_token;
	run_start = token;
    }

    last_token = token;

    if (nb != 0) {
	/* deflate the data starting at offset */
	tx_strm.avail_in = 0;
	tx_strm.avail_out = 0;
	do {
	    if (tx_strm.avail_in == 0 && nb != 0) {
		/* give it some more input */
		n = MIN(nb, CHUNK_SIZE);
		tx_strm.next_in = (Bytef *)map_ptr(buf, offset, n);
		tx_strm.avail_in = n;
		nb -= n;
		offset += n;
	    }
	    if (tx_strm.avail_out == 0) {
		tx_strm.next_out = (Bytef *)(obuf + 2);
		tx_strm.avail_out = MAX_DATA_COUNT;
	    }
	    r = deflate(&tx_strm, nb? Z_NO_FLUSH: Z_PACKET_FLUSH);
	    if (r != Z_OK) {
		rprintf(FERROR, "deflate returned %d\n", r);
		exit_cleanup(1);
	    }
	    if (nb == 0 || tx_strm.avail_out == 0) {
		n = MAX_DATA_COUNT - tx_strm.avail_out;
		if (n > 0) {
		    obuf[0] = DEFLATED_DATA + (n >> 8);
		    obuf[1] = n;
		    write_buf(f, obuf, n+2);
		}
	    }
	} while (nb != 0 || tx_strm.avail_out == 0);
    }

    if (token != -1) {
	/* add the data in the current block to the compressor's
	   history and hash table */
	tx_strm.next_in = (Bytef *)map_ptr(buf, offset, toklen);
	tx_strm.avail_in = toklen;
	tx_strm.next_out = NULL;
	tx_strm.avail_out = 2 * toklen;
	r = deflate(&tx_strm, Z_INSERT_ONLY);
	if (r != Z_OK || tx_strm.avail_in != 0) {
	    rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
		    r, tx_strm.avail_in);
	    exit_cleanup(1);
	}

    } else {
	/* end of file - clean up */
	write_byte(f, END_FLAG);
    }
}


/* tells us what the receiver is in the middle of doing */
static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state;

/* for inflating stuff */
static z_stream rx_strm;
static char *cbuf;
static char *dbuf;

/* for decoding runs of tokens */
static int rx_token;
static int rx_run;

/* Receive a deflated token and inflate it */
static int
recv_deflated_token(int f, char **data)
{
    int n, r, flag;
    static int init_done;
    static int saved_flag;

    for (;;) {
	switch (recv_state) {
	case r_init:
	    if (!init_done) {
		rx_strm.next_out = NULL;
		rx_strm.zalloc = z_alloc;
		rx_strm.zfree = z_free;
		if (inflateInit2(&rx_strm, -15) != Z_OK) {
		    rprintf(FERROR, "inflate init failed\n");
		    exit_cleanup(1);
		}
		if ((cbuf = malloc(MAX_DATA_COUNT)) == NULL
		    || (dbuf = malloc(CHUNK_SIZE)) == NULL)
		    out_of_memory("recv_deflated_token");
		init_done = 1;
	    } else {
		inflateReset(&rx_strm);
	    }
	    recv_state = r_idle;
	    rx_token = 0;
	    break;
	    
	case r_idle:
	case r_inflated:
	    if (saved_flag) {
		flag = saved_flag & 0xff;
		saved_flag = 0;
	    } else
		flag = read_byte(f);
	    if ((flag & 0xC0) == DEFLATED_DATA) {
		n = ((flag & 0x3f) << 8) + read_byte(f);
		read_buf(f, cbuf, n);
		rx_strm.next_in = (Bytef *)cbuf;
		rx_strm.avail_in = n;
		recv_state = r_inflating;
		break;
	    }
	    if (recv_state == r_inflated) {
		/* check previous inflated stuff ended correctly */
		rx_strm.avail_in = 0;
		rx_strm.next_out = (Bytef *)dbuf;
		rx_strm.avail_out = CHUNK_SIZE;
		r = inflate(&rx_strm, Z_PACKET_FLUSH);
		n = CHUNK_SIZE - rx_strm.avail_out;
		if (r != Z_OK) {
		    rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
			    r, n);
		    exit_cleanup(1);
		}
		if (n != 0) {
		    /* have to return some more data and
		       save the flag for later. */
		    saved_flag = flag + 0x10000;
		    if (rx_strm.avail_out != 0)
			recv_state = r_idle;
		    *data = dbuf;
		    return n;
		}
		recv_state = r_idle;
	    }
	    if (flag == END_FLAG) {
		/* that's all folks */
		recv_state = r_init;
		return 0;
	    }

	    /* here we have a token of some kind */
	    if (flag & TOKEN_REL) {
		rx_token += flag & 0x3f;
		flag >>= 6;
	    } else
		rx_token = read_int(f);
	    if (flag & 1) {
		rx_run = read_byte(f);
		rx_run += read_byte(f) << 8;
		recv_state = r_running;
	    }
	    return -1 - rx_token;

	case r_inflating:
	    rx_strm.next_out = (Bytef *)dbuf;
	    rx_strm.avail_out = CHUNK_SIZE;
	    r = inflate(&rx_strm, Z_NO_FLUSH);
	    n = CHUNK_SIZE - rx_strm.avail_out;
	    if (r != Z_OK) {
		rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
		exit_cleanup(1);
	    }
	    if (rx_strm.avail_in == 0)
		recv_state = r_inflated;
	    if (n != 0) {
		*data = dbuf;
		return n;
	    }
	    break;

	case r_running:
	    ++rx_token;
	    if (--rx_run == 0)
		recv_state = r_idle;
	    return -1 - rx_token;
	}
    }
}

/*
 * put the data corresponding to a token that we've just returned
 * from recv_deflated_token into the decompressor's history buffer.
 */
void
see_deflate_token(char *buf, int len)
{
    int r;

    rx_strm.next_in = (Bytef *)buf;
    rx_strm.avail_in = len;
    r = inflateIncomp(&rx_strm);
    if (r != Z_OK) {
	rprintf(FERROR, "inflateIncomp returned %d\n", r);
	exit_cleanup(1);
    }
}

/*
 * transmit a verbatim buffer of length n followed by a token 
 * If token == -1 then we have reached EOF 
 * If n == 0 then don't send a buffer
 */
void send_token(int f,int token,struct map_struct *buf,int offset,
		int n,int toklen)
{
  if (!do_compression) {
    simple_send_token(f,token,buf,offset,n);
  } else {
    send_deflated_token(f, token, buf, offset, n, toklen);
  }
}


/*
 * receive a token or buffer from the other end. If the reurn value is >0 then
 * it is a data buffer of that length, and *data will point at the data.
 * if the return value is -i then it represents token i-1
 * if the return value is 0 then the end has been reached
 */
int recv_token(int f,char **data)
{
  int tok;

  if (!do_compression) {
    tok = simple_recv_token(f,data);
  } else {
    tok = recv_deflated_token(f, data);
  }
  return tok;
}

/*
 * look at the data corresponding to a token, if necessary
 */
void see_token(char *data, int toklen)
{
    if (do_compression)
	see_deflate_token(data, toklen);
}
Commit	Line	Data
70d794dc AT	1	/*
	2	Copyright (C) Andrew Tridgell 1996
	3	Copyright (C) Paul Mackerras 1996
	4
	5	This program is free software; you can redistribute it and/or modify
	6	it under the terms of the GNU General Public License as published by
	7	the Free Software Foundation; either version 2 of the License, or
	8	(at your option) any later version.
	9
	10	This program is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	GNU General Public License for more details.
	14
	15	You should have received a copy of the GNU General Public License
	16	along with this program; if not, write to the Free Software
	17	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	18	*/
	19
	20	#include "rsync.h"
861c20b4	21	#include "lib/zlib.h"
70d794dc AT	22
	23	extern int do_compression;
	24
	25
	26	/* non-compressing recv token */
	27	static int simple_recv_token(int f,char **data)
	28	{
c5eb3650 AT	29	static int residue;
	30	static char *buf;
	31	int n;
70d794dc	32
c5eb3650 AT	33	if (!buf) {
	34	buf = (char *)malloc(CHUNK_SIZE);
	35	if (!buf) out_of_memory("simple_recv_token");
	36	}
70d794dc	37
c5eb3650 AT	38	if (residue == 0) {
	39	int i = read_int(f);
	40	if (i <= 0) return i;
	41	residue = i;
	42	}
70d794dc	43
c5eb3650 AT	44	*data = buf;
	45	n = MIN(CHUNK_SIZE,residue);
	46	residue -= n;
	47	read_buf(f,buf,n);
	48	return n;
70d794dc AT	49	}
	50
	51
	52	/* non-compressing send token */
c6e7fcb4 AT	53	static void simple_send_token(int f,int token,
c6e7fcb4 AT	54	struct map_struct *buf,int offset,int n)
70d794dc	55	{
c5eb3650 AT	56	if (n > 0) {
	57	int l = 0;
	58	while (l < n) {
	59	int n1 = MIN(CHUNK_SIZE,n-l);
	60	write_int(f,n1);
	61	write_buf(f,map_ptr(buf,offset+l,n1),n1);
	62	l += n1;
	63	}
	64	}
	65	write_int(f,-(token+1));
70d794dc AT	66	}
	67
	68
861c20b4 PM	69	/* Memory allocation/freeing routines, called by zlib stuff. */
	70	static void *
	71	z_alloc(void *opaque, uInt items, uInt size)
	72	{
	73	return malloc(items * size);
	74	}
	75
	76	static void
	77	z_free(void opaque, void adrs, uInt nbytes)
	78	{
	79	free(adrs);
	80	}
	81
	82	/* Flag bytes in compressed stream are encoded as follows: */
	83	#define END_FLAG 0 /* that's all folks */
	84	#define TOKEN_LONG 0x20 /* followed by 32-bit token number */
	85	#define TOKENRUN_LONG 0x21 /* ditto with 16-bit run count */
	86	#define DEFLATED_DATA 0x40 /* + 6-bit high len, then low len byte */
	87	#define TOKEN_REL 0x80 /* + 6-bit relative token number */
	88	#define TOKENRUN_REL 0xc0 /* ditto with 16-bit run count */
	89
	90	#define MAX_DATA_COUNT 16383 /* fit 14 bit count into 2 bytes with flags */
	91
	92	/* For coding runs of tokens */
	93	static int last_token = -1;
	94	static int run_start;
	95	static int last_run_end;
	96
	97	/* Deflation state */
	98	static z_stream tx_strm;
	99
	100	/* Output buffer */
3a6a366f	101	static char *obuf;
861c20b4 PM	102
	103	/* Send a deflated token */
	104	static void
	105	send_deflated_token(int f, int token,
	106	struct map_struct *buf, int offset, int nb, int toklen)
	107	{
	108	int n, r;
	109	static int init_done;
	110
	111	if (last_token == -1) {
	112	/* initialization */
	113	if (!init_done) {
	114	tx_strm.next_in = NULL;
	115	tx_strm.zalloc = z_alloc;
	116	tx_strm.zfree = z_free;
	117	if (deflateInit2(&tx_strm, Z_DEFAULT_COMPRESSION, 8,
f8062104	118	-15, 8, Z_DEFAULT_STRATEGY) != Z_OK) {
9486289c	119	rprintf(FERROR, "compression init failed\n");
861c20b4 PM	120	exit_cleanup(1);
	121	}
	122	if ((obuf = malloc(MAX_DATA_COUNT+2)) == NULL)
	123	out_of_memory("send_deflated_token");
	124	init_done = 1;
	125	} else
	126	deflateReset(&tx_strm);
	127	run_start = token;
	128	last_run_end = 0;
	129
	130	} else if (nb != 0 \|\| token != last_token + 1
	131	\|\| token >= run_start + 65536) {
	132	/* output previous run */
	133	r = run_start - last_run_end;
	134	n = last_token - run_start;
	135	if (r >= 0 && r <= 63) {
	136	write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
	137	} else {
	138	write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
	139	write_int(f, run_start);
	140	}
	141	if (n != 0) {
	142	write_byte(f, n);
	143	write_byte(f, n >> 8);
	144	}
	145	last_run_end = last_token;
	146	run_start = token;
	147	}
	148
	149	last_token = token;
	150
	151	if (nb != 0) {
	152	/* deflate the data starting at offset */
	153	tx_strm.avail_in = 0;
	154	tx_strm.avail_out = 0;
	155	do {
	156	if (tx_strm.avail_in == 0 && nb != 0) {
	157	/* give it some more input */
	158	n = MIN(nb, CHUNK_SIZE);
1634f4c4	159	tx_strm.next_in = (Bytef *)map_ptr(buf, offset, n);
861c20b4 PM	160	tx_strm.avail_in = n;
	161	nb -= n;
	162	offset += n;
	163	}
	164	if (tx_strm.avail_out == 0) {
1634f4c4	165	tx_strm.next_out = (Bytef *)(obuf + 2);
861c20b4 PM	166	tx_strm.avail_out = MAX_DATA_COUNT;
	167	}
	168	r = deflate(&tx_strm, nb? Z_NO_FLUSH: Z_PACKET_FLUSH);
	169	if (r != Z_OK) {
9486289c	170	rprintf(FERROR, "deflate returned %d\n", r);
861c20b4 PM	171	exit_cleanup(1);
	172	}
	173	if (nb == 0 \|\| tx_strm.avail_out == 0) {
	174	n = MAX_DATA_COUNT - tx_strm.avail_out;
	175	if (n > 0) {
	176	obuf[0] = DEFLATED_DATA + (n >> 8);
	177	obuf[1] = n;
	178	write_buf(f, obuf, n+2);
	179	}
	180	}
	181	} while (nb != 0 \|\| tx_strm.avail_out == 0);
	182	}
	183
	184	if (token != -1) {
	185	/* add the data in the current block to the compressor's
	186	history and hash table */
1634f4c4	187	tx_strm.next_in = (Bytef *)map_ptr(buf, offset, toklen);
861c20b4 PM	188	tx_strm.avail_in = toklen;
	189	tx_strm.next_out = NULL;
	190	tx_strm.avail_out = 2 * toklen;
	191	r = deflate(&tx_strm, Z_INSERT_ONLY);
	192	if (r != Z_OK \|\| tx_strm.avail_in != 0) {
9486289c	193	rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
861c20b4 PM	194	r, tx_strm.avail_in);
	195	exit_cleanup(1);
	196	}
	197
	198	} else {
	199	/* end of file - clean up */
	200	write_byte(f, END_FLAG);
	201	}
	202	}
	203
	204
	205	/* tells us what the receiver is in the middle of doing */
	206	static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state;
70d794dc	207
861c20b4 PM	208	/* for inflating stuff */
	209	static z_stream rx_strm;
	210	static char *cbuf;
	211	static char *dbuf;
	212
	213	/* for decoding runs of tokens */
	214	static int rx_token;
	215	static int rx_run;
	216
	217	/* Receive a deflated token and inflate it */
	218	static int
	219	recv_deflated_token(int f, char **data)
	220	{
	221	int n, r, flag;
3a6a366f AT	222	static int init_done;
3a6a366f AT	223	static int saved_flag;
861c20b4 PM	224
	225	for (;;) {
	226	switch (recv_state) {
	227	case r_init:
	228	if (!init_done) {
	229	rx_strm.next_out = NULL;
	230	rx_strm.zalloc = z_alloc;
	231	rx_strm.zfree = z_free;
	232	if (inflateInit2(&rx_strm, -15) != Z_OK) {
9486289c	233	rprintf(FERROR, "inflate init failed\n");
861c20b4 PM	234	exit_cleanup(1);
	235	}
	236	if ((cbuf = malloc(MAX_DATA_COUNT)) == NULL
	237	\|\| (dbuf = malloc(CHUNK_SIZE)) == NULL)
	238	out_of_memory("recv_deflated_token");
	239	init_done = 1;
	240	} else {
	241	inflateReset(&rx_strm);
	242	}
	243	recv_state = r_idle;
5be59dc5	244	rx_token = 0;
861c20b4 PM	245	break;
	246
	247	case r_idle:
	248	case r_inflated:
b8d4524b PM	249	if (saved_flag) {
	250	flag = saved_flag & 0xff;
	251	saved_flag = 0;
	252	} else
	253	flag = read_byte(f);
861c20b4 PM	254	if ((flag & 0xC0) == DEFLATED_DATA) {
	255	n = ((flag & 0x3f) << 8) + read_byte(f);
	256	read_buf(f, cbuf, n);
1634f4c4	257	rx_strm.next_in = (Bytef *)cbuf;
861c20b4 PM	258	rx_strm.avail_in = n;
	259	recv_state = r_inflating;
	260	break;
	261	}
	262	if (recv_state == r_inflated) {
	263	/* check previous inflated stuff ended correctly */
	264	rx_strm.avail_in = 0;
1634f4c4	265	rx_strm.next_out = (Bytef *)dbuf;
861c20b4 PM	266	rx_strm.avail_out = CHUNK_SIZE;
	267	r = inflate(&rx_strm, Z_PACKET_FLUSH);
	268	n = CHUNK_SIZE - rx_strm.avail_out;
b8d4524b	269	if (r != Z_OK) {
9486289c	270	rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
861c20b4 PM	271	r, n);
	272	exit_cleanup(1);
	273	}
b8d4524b PM	274	if (n != 0) {
	275	/* have to return some more data and
	276	save the flag for later. */
	277	saved_flag = flag + 0x10000;
	278	if (rx_strm.avail_out != 0)
	279	recv_state = r_idle;
	280	*data = dbuf;
	281	return n;
	282	}
861c20b4 PM	283	recv_state = r_idle;
	284	}
	285	if (flag == END_FLAG) {
	286	/* that's all folks */
	287	recv_state = r_init;
	288	return 0;
	289	}
	290
	291	/* here we have a token of some kind */
	292	if (flag & TOKEN_REL) {
	293	rx_token += flag & 0x3f;
	294	flag >>= 6;
	295	} else
	296	rx_token = read_int(f);
	297	if (flag & 1) {
	298	rx_run = read_byte(f);
	299	rx_run += read_byte(f) << 8;
	300	recv_state = r_running;
	301	}
	302	return -1 - rx_token;
	303
	304	case r_inflating:
1634f4c4	305	rx_strm.next_out = (Bytef *)dbuf;
861c20b4 PM	306	rx_strm.avail_out = CHUNK_SIZE;
	307	r = inflate(&rx_strm, Z_NO_FLUSH);
	308	n = CHUNK_SIZE - rx_strm.avail_out;
280cbb85	309	if (r != Z_OK) {
9486289c	310	rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
861c20b4 PM	311	exit_cleanup(1);
861c20b4 PM	312	}
b8d4524b	313	if (rx_strm.avail_in == 0)
861c20b4	314	recv_state = r_inflated;
280cbb85 PM	315	if (n != 0) {
	316	*data = dbuf;
	317	return n;
	318	}
	319	break;
861c20b4 PM	320
	321	case r_running:
	322	++rx_token;
	323	if (--rx_run == 0)
	324	recv_state = r_idle;
	325	return -1 - rx_token;
	326	}
	327	}
	328	}
	329
	330	/*
	331	* put the data corresponding to a token that we've just returned
	332	* from recv_deflated_token into the decompressor's history buffer.
	333	*/
	334	void
	335	see_deflate_token(char *buf, int len)
	336	{
	337	int r;
	338
1634f4c4	339	rx_strm.next_in = (Bytef *)buf;
861c20b4 PM	340	rx_strm.avail_in = len;
	341	r = inflateIncomp(&rx_strm);
	342	if (r != Z_OK) {
9486289c	343	rprintf(FERROR, "inflateIncomp returned %d\n", r);
861c20b4 PM	344	exit_cleanup(1);
	345	}
	346	}
70d794dc AT	347
	348	/*
	349	* transmit a verbatim buffer of length n followed by a token
	350	* If token == -1 then we have reached EOF
	351	* If n == 0 then don't send a buffer
70d794dc	352	*/
9e31c482 AT	353	void send_token(int f,int token,struct map_struct *buf,int offset,
9e31c482 AT	354	int n,int toklen)
70d794dc AT	355	{
	356	if (!do_compression) {
	357	simple_send_token(f,token,buf,offset,n);
861c20b4 PM	358	} else {
861c20b4 PM	359	send_deflated_token(f, token, buf, offset, n, toklen);
70d794dc	360	}
70d794dc AT	361	}
	362
	363
	364	/*
	365	* receive a token or buffer from the other end. If the reurn value is >0 then
	366	* it is a data buffer of that length, and *data will point at the data.
	367	* if the return value is -i then it represents token i-1
	368	* if the return value is 0 then the end has been reached
	369	*/
	370	int recv_token(int f,char **data)
	371	{
861c20b4 PM	372	int tok;
861c20b4 PM	373
70d794dc	374	if (!do_compression) {
861c20b4 PM	375	tok = simple_recv_token(f,data);
	376	} else {
	377	tok = recv_deflated_token(f, data);
70d794dc	378	}
861c20b4 PM	379	return tok;
	380	}
	381
	382	/*
	383	* look at the data corresponding to a token, if necessary
	384	*/
	385	void see_token(char *data, int toklen)
	386	{
861c20b4 PM	387	if (do_compression)
861c20b4 PM	388	see_deflate_token(data, toklen);
70d794dc	389	}