2 Copyright (C) Andrew Tridgell 1996
3 Copyright (C) Paul Mackerras 1996
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.
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.
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.
21 #include "zlib/zlib.h"
23 extern int do_compression;
25 extern int def_compress_level;
27 static int compression_level;
29 /* determine the compression level based on a wildcard filename list */
30 void set_compression(char *fname)
38 compression_level = def_compress_level;
39 dont = lp_dont_compress(module_id);
44 if (dont[0] == '*' && !dont[1]) {
45 /* an optimization to skip the rest of this routine */
46 compression_level = 0;
51 fname = strdup(fname);
58 for (tok = strtok(dont, " "); tok; tok = strtok(NULL, " ")) {
59 if (wildmatch(tok, fname)) {
60 compression_level = 0;
68 /* non-compressing recv token */
69 static int32 simple_recv_token(int f, char **data)
76 buf = new_array(char, CHUNK_SIZE);
78 out_of_memory("simple_recv_token");
82 int32 i = read_int(f);
89 n = MIN(CHUNK_SIZE,residue);
96 /* non-compressing send token */
97 static void simple_send_token(int f, int32 token, struct map_struct *buf,
98 OFF_T offset, int32 n)
103 int32 n1 = MIN(CHUNK_SIZE, n-len);
105 write_buf(f, map_ptr(buf, offset+len, n1), n1);
109 /* a -2 token means to send data only and no token */
111 write_int(f, -(token+1));
115 /* Flag bytes in compressed stream are encoded as follows: */
116 #define END_FLAG 0 /* that's all folks */
117 #define TOKEN_LONG 0x20 /* followed by 32-bit token number */
118 #define TOKENRUN_LONG 0x21 /* ditto with 16-bit run count */
119 #define DEFLATED_DATA 0x40 /* + 6-bit high len, then low len byte */
120 #define TOKEN_REL 0x80 /* + 6-bit relative token number */
121 #define TOKENRUN_REL 0xc0 /* ditto with 16-bit run count */
123 #define MAX_DATA_COUNT 16383 /* fit 14 bit count into 2 bytes with flags */
125 /* zlib.h says that if we want to be able to compress something in a single
126 * call, avail_out must be at least 0.1% larger than avail_in plus 12 bytes.
127 * We'll add in 0.1%+16, just to be safe (and we'll avoid floating point,
128 * to ensure that this is a compile-time value). */
129 #define AVAIL_OUT_SIZE(avail_in_size) ((avail_in_size)*1001/1000+16)
131 /* For coding runs of tokens */
132 static int32 last_token = -1;
133 static int32 run_start;
134 static int32 last_run_end;
136 /* Deflation state */
137 static z_stream tx_strm;
142 /* We want obuf to be able to hold both MAX_DATA_COUNT+2 bytes as well as
143 * AVAIL_OUT_SIZE(CHUNK_SIZE) bytes, so make sure that it's large enough. */
144 #if MAX_DATA_COUNT+2 > AVAIL_OUT_SIZE(CHUNK_SIZE)
145 #define OBUF_SIZE (MAX_DATA_COUNT+2)
147 #define OBUF_SIZE AVAIL_OUT_SIZE(CHUNK_SIZE)
150 /* Send a deflated token */
152 send_deflated_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
153 int32 nb, int32 toklen)
156 static int init_done, flush_pending;
158 if (last_token == -1) {
161 tx_strm.next_in = NULL;
162 tx_strm.zalloc = NULL;
163 tx_strm.zfree = NULL;
164 if (deflateInit2(&tx_strm, compression_level,
166 Z_DEFAULT_STRATEGY) != Z_OK) {
167 rprintf(FERROR, "compression init failed\n");
168 exit_cleanup(RERR_STREAMIO);
170 if ((obuf = new_array(char, OBUF_SIZE)) == NULL)
171 out_of_memory("send_deflated_token");
174 deflateReset(&tx_strm);
179 } else if (last_token == -2) {
182 } else if (nb != 0 || token != last_token + 1
183 || token >= run_start + 65536) {
184 /* output previous run */
185 r = run_start - last_run_end;
186 n = last_token - run_start;
187 if (r >= 0 && r <= 63) {
188 write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
190 write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
191 write_int(f, run_start);
195 write_byte(f, n >> 8);
197 last_run_end = last_token;
203 if (nb != 0 || flush_pending) {
204 /* deflate the data starting at offset */
205 int flush = Z_NO_FLUSH;
206 tx_strm.avail_in = 0;
207 tx_strm.avail_out = 0;
209 if (tx_strm.avail_in == 0 && nb != 0) {
210 /* give it some more input */
211 n = MIN(nb, CHUNK_SIZE);
212 tx_strm.next_in = (Bytef *)
213 map_ptr(buf, offset, n);
214 tx_strm.avail_in = n;
218 if (tx_strm.avail_out == 0) {
219 tx_strm.next_out = (Bytef *)(obuf + 2);
220 tx_strm.avail_out = MAX_DATA_COUNT;
221 if (flush != Z_NO_FLUSH) {
223 * We left the last 4 bytes in the
224 * buffer, in case they are the
225 * last 4. Move them to the front.
227 memcpy(tx_strm.next_out,
228 obuf+MAX_DATA_COUNT-2, 4);
229 tx_strm.next_out += 4;
230 tx_strm.avail_out -= 4;
233 if (nb == 0 && token != -2)
234 flush = Z_SYNC_FLUSH;
235 r = deflate(&tx_strm, flush);
237 rprintf(FERROR, "deflate returned %d\n", r);
238 exit_cleanup(RERR_STREAMIO);
240 if (nb == 0 || tx_strm.avail_out == 0) {
241 n = MAX_DATA_COUNT - tx_strm.avail_out;
242 if (flush != Z_NO_FLUSH) {
244 * We have to trim off the last 4
245 * bytes of output when flushing
246 * (they are just 0, 0, ff, ff).
251 obuf[0] = DEFLATED_DATA + (n >> 8);
253 write_buf(f, obuf, n+2);
256 } while (nb != 0 || tx_strm.avail_out == 0);
257 flush_pending = token == -2;
261 /* end of file - clean up */
262 write_byte(f, END_FLAG);
263 } else if (token != -2) {
264 /* Add the data in the current block to the compressor's
265 * history and hash table. */
267 /* Break up long sections in the same way that
268 * see_deflate_token() does. */
269 int32 n1 = toklen > 0xffff ? 0xffff : toklen;
271 tx_strm.next_in = (Bytef *)map_ptr(buf, offset, n1);
272 tx_strm.avail_in = n1;
273 tx_strm.next_out = (Bytef *) obuf;
274 tx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
275 r = deflate(&tx_strm, Z_INSERT_ONLY);
276 if (r != Z_OK || tx_strm.avail_in != 0) {
277 rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
278 r, tx_strm.avail_in);
279 exit_cleanup(RERR_STREAMIO);
281 } while (toklen > 0);
286 /* tells us what the receiver is in the middle of doing */
287 static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state;
289 /* for inflating stuff */
290 static z_stream rx_strm;
294 /* for decoding runs of tokens */
295 static int32 rx_token;
298 /* Receive a deflated token and inflate it */
299 static int32 recv_deflated_token(int f, char **data)
301 static int init_done;
302 static int32 saved_flag;
307 switch (recv_state) {
310 rx_strm.next_out = NULL;
311 rx_strm.zalloc = NULL;
312 rx_strm.zfree = NULL;
313 if (inflateInit2(&rx_strm, -15) != Z_OK) {
314 rprintf(FERROR, "inflate init failed\n");
315 exit_cleanup(RERR_STREAMIO);
317 if (!(cbuf = new_array(char, MAX_DATA_COUNT))
318 || !(dbuf = new_array(char, AVAIL_OUT_SIZE(CHUNK_SIZE))))
319 out_of_memory("recv_deflated_token");
322 inflateReset(&rx_strm);
331 flag = saved_flag & 0xff;
335 if ((flag & 0xC0) == DEFLATED_DATA) {
336 n = ((flag & 0x3f) << 8) + read_byte(f);
337 read_buf(f, cbuf, n);
338 rx_strm.next_in = (Bytef *)cbuf;
339 rx_strm.avail_in = n;
340 recv_state = r_inflating;
343 if (recv_state == r_inflated) {
344 /* check previous inflated stuff ended correctly */
345 rx_strm.avail_in = 0;
346 rx_strm.next_out = (Bytef *)dbuf;
347 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
348 r = inflate(&rx_strm, Z_SYNC_FLUSH);
349 n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
351 * Z_BUF_ERROR just means no progress was
352 * made, i.e. the decompressor didn't have
353 * any pending output for us.
355 if (r != Z_OK && r != Z_BUF_ERROR) {
356 rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
358 exit_cleanup(RERR_STREAMIO);
360 if (n != 0 && r != Z_BUF_ERROR) {
361 /* have to return some more data and
362 save the flag for later. */
363 saved_flag = flag + 0x10000;
368 * At this point the decompressor should
369 * be expecting to see the 0, 0, ff, ff bytes.
371 if (!inflateSyncPoint(&rx_strm)) {
372 rprintf(FERROR, "decompressor lost sync!\n");
373 exit_cleanup(RERR_STREAMIO);
375 rx_strm.avail_in = 4;
376 rx_strm.next_in = (Bytef *)cbuf;
377 cbuf[0] = cbuf[1] = 0;
378 cbuf[2] = cbuf[3] = 0xff;
379 inflate(&rx_strm, Z_SYNC_FLUSH);
382 if (flag == END_FLAG) {
383 /* that's all folks */
388 /* here we have a token of some kind */
389 if (flag & TOKEN_REL) {
390 rx_token += flag & 0x3f;
393 rx_token = read_int(f);
395 rx_run = read_byte(f);
396 rx_run += read_byte(f) << 8;
397 recv_state = r_running;
399 return -1 - rx_token;
402 rx_strm.next_out = (Bytef *)dbuf;
403 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
404 r = inflate(&rx_strm, Z_NO_FLUSH);
405 n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
407 rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
408 exit_cleanup(RERR_STREAMIO);
410 if (rx_strm.avail_in == 0)
411 recv_state = r_inflated;
422 return -1 - rx_token;
428 * put the data corresponding to a token that we've just returned
429 * from recv_deflated_token into the decompressor's history buffer.
431 static void see_deflate_token(char *buf, int32 len)
435 unsigned char hdr[5];
437 rx_strm.avail_in = 0;
441 if (rx_strm.avail_in == 0 && len != 0) {
443 /* Give it a fake stored-block header. */
444 rx_strm.next_in = (Bytef *)hdr;
445 rx_strm.avail_in = 5;
450 hdr[2] = blklen >> 8;
454 rx_strm.next_in = (Bytef *)buf;
455 rx_strm.avail_in = blklen;
460 rx_strm.next_out = (Bytef *)dbuf;
461 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
462 r = inflate(&rx_strm, Z_SYNC_FLUSH);
464 rprintf(FERROR, "inflate (token) returned %d\n", r);
465 exit_cleanup(RERR_STREAMIO);
467 } while (len || rx_strm.avail_out == 0);
471 * Transmit a verbatim buffer of length @p n followed by a token.
472 * If token == -1 then we have reached EOF
473 * If n == 0 then don't send a buffer
475 void send_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
476 int32 n, int32 toklen)
479 simple_send_token(f, token, buf, offset, n);
481 send_deflated_token(f, token, buf, offset, n, toklen);
486 * receive a token or buffer from the other end. If the reurn value is >0 then
487 * it is a data buffer of that length, and *data will point at the data.
488 * if the return value is -i then it represents token i-1
489 * if the return value is 0 then the end has been reached
491 int32 recv_token(int f, char **data)
495 if (!do_compression) {
496 tok = simple_recv_token(f,data);
498 tok = recv_deflated_token(f, data);
504 * look at the data corresponding to a token, if necessary
506 void see_token(char *data, int32 toklen)
509 see_deflate_token(data, toklen);