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/*
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 = 0;
static char *buf = NULL;
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 = NULL;
/* 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) {
fprintf(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) {
fprintf(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) {
fprintf(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 = 0;
static int saved_flag = 0;
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) {
fprintf(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) {
fprintf(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) {
fprintf(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) {
fprintf(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);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.