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, per_file_default_level;
29 /* determine the compression level based on a wildcard filename list */
30 void set_compression(char *fname)
32 static char *match_list;
39 char *t, *f = lp_dont_compress(module_id);
41 if (!(match_list = t = new_array(char, len + 2)))
42 out_of_memory("set_compression");
49 if (isupper(*(unsigned char *)f))
50 *t++ = tolower(*(unsigned char *)f);
53 } while (*++f != ' ' && *f);
56 /* Optimize a match-string of "*". */
57 if (t - match_list == 2 && match_list[0] == '*') {
59 per_file_default_level = 0;
61 per_file_default_level = def_compress_level;
65 compression_level = per_file_default_level;
70 if ((s = strrchr(fname, '/')) != NULL)
73 for (s = match_list; *s; s += strlen(s) + 1) {
74 if (iwildmatch(s, fname)) {
75 compression_level = 0;
81 /* non-compressing recv token */
82 static int32 simple_recv_token(int f, char **data)
89 buf = new_array(char, CHUNK_SIZE);
91 out_of_memory("simple_recv_token");
95 int32 i = read_int(f);
102 n = MIN(CHUNK_SIZE,residue);
109 /* non-compressing send token */
110 static void simple_send_token(int f, int32 token, struct map_struct *buf,
111 OFF_T offset, int32 n)
116 int32 n1 = MIN(CHUNK_SIZE, n-len);
118 write_buf(f, map_ptr(buf, offset+len, n1), n1);
122 /* a -2 token means to send data only and no token */
124 write_int(f, -(token+1));
128 /* Flag bytes in compressed stream are encoded as follows: */
129 #define END_FLAG 0 /* that's all folks */
130 #define TOKEN_LONG 0x20 /* followed by 32-bit token number */
131 #define TOKENRUN_LONG 0x21 /* ditto with 16-bit run count */
132 #define DEFLATED_DATA 0x40 /* + 6-bit high len, then low len byte */
133 #define TOKEN_REL 0x80 /* + 6-bit relative token number */
134 #define TOKENRUN_REL 0xc0 /* ditto with 16-bit run count */
136 #define MAX_DATA_COUNT 16383 /* fit 14 bit count into 2 bytes with flags */
138 /* zlib.h says that if we want to be able to compress something in a single
139 * call, avail_out must be at least 0.1% larger than avail_in plus 12 bytes.
140 * We'll add in 0.1%+16, just to be safe (and we'll avoid floating point,
141 * to ensure that this is a compile-time value). */
142 #define AVAIL_OUT_SIZE(avail_in_size) ((avail_in_size)*1001/1000+16)
144 /* For coding runs of tokens */
145 static int32 last_token = -1;
146 static int32 run_start;
147 static int32 last_run_end;
149 /* Deflation state */
150 static z_stream tx_strm;
155 /* We want obuf to be able to hold both MAX_DATA_COUNT+2 bytes as well as
156 * AVAIL_OUT_SIZE(CHUNK_SIZE) bytes, so make sure that it's large enough. */
157 #if MAX_DATA_COUNT+2 > AVAIL_OUT_SIZE(CHUNK_SIZE)
158 #define OBUF_SIZE (MAX_DATA_COUNT+2)
160 #define OBUF_SIZE AVAIL_OUT_SIZE(CHUNK_SIZE)
163 /* Send a deflated token */
165 send_deflated_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
166 int32 nb, int32 toklen)
169 static int init_done, flush_pending;
171 if (last_token == -1) {
174 tx_strm.next_in = NULL;
175 tx_strm.zalloc = NULL;
176 tx_strm.zfree = NULL;
177 if (deflateInit2(&tx_strm, compression_level,
179 Z_DEFAULT_STRATEGY) != Z_OK) {
180 rprintf(FERROR, "compression init failed\n");
181 exit_cleanup(RERR_STREAMIO);
183 if ((obuf = new_array(char, OBUF_SIZE)) == NULL)
184 out_of_memory("send_deflated_token");
187 deflateReset(&tx_strm);
192 } else if (last_token == -2) {
195 } else if (nb != 0 || token != last_token + 1
196 || token >= run_start + 65536) {
197 /* output previous run */
198 r = run_start - last_run_end;
199 n = last_token - run_start;
200 if (r >= 0 && r <= 63) {
201 write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
203 write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
204 write_int(f, run_start);
208 write_byte(f, n >> 8);
210 last_run_end = last_token;
216 if (nb != 0 || flush_pending) {
217 /* deflate the data starting at offset */
218 int flush = Z_NO_FLUSH;
219 tx_strm.avail_in = 0;
220 tx_strm.avail_out = 0;
222 if (tx_strm.avail_in == 0 && nb != 0) {
223 /* give it some more input */
224 n = MIN(nb, CHUNK_SIZE);
225 tx_strm.next_in = (Bytef *)
226 map_ptr(buf, offset, n);
227 tx_strm.avail_in = n;
231 if (tx_strm.avail_out == 0) {
232 tx_strm.next_out = (Bytef *)(obuf + 2);
233 tx_strm.avail_out = MAX_DATA_COUNT;
234 if (flush != Z_NO_FLUSH) {
236 * We left the last 4 bytes in the
237 * buffer, in case they are the
238 * last 4. Move them to the front.
240 memcpy(tx_strm.next_out,
241 obuf+MAX_DATA_COUNT-2, 4);
242 tx_strm.next_out += 4;
243 tx_strm.avail_out -= 4;
246 if (nb == 0 && token != -2)
247 flush = Z_SYNC_FLUSH;
248 r = deflate(&tx_strm, flush);
250 rprintf(FERROR, "deflate returned %d\n", r);
251 exit_cleanup(RERR_STREAMIO);
253 if (nb == 0 || tx_strm.avail_out == 0) {
254 n = MAX_DATA_COUNT - tx_strm.avail_out;
255 if (flush != Z_NO_FLUSH) {
257 * We have to trim off the last 4
258 * bytes of output when flushing
259 * (they are just 0, 0, ff, ff).
264 obuf[0] = DEFLATED_DATA + (n >> 8);
266 write_buf(f, obuf, n+2);
269 } while (nb != 0 || tx_strm.avail_out == 0);
270 flush_pending = token == -2;
274 /* end of file - clean up */
275 write_byte(f, END_FLAG);
276 } else if (token != -2) {
277 /* Add the data in the current block to the compressor's
278 * history and hash table. */
280 /* Break up long sections in the same way that
281 * see_deflate_token() does. */
282 int32 n1 = toklen > 0xffff ? 0xffff : toklen;
284 tx_strm.next_in = (Bytef *)map_ptr(buf, offset, n1);
285 tx_strm.avail_in = n1;
286 tx_strm.next_out = (Bytef *) obuf;
287 tx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
288 r = deflate(&tx_strm, Z_INSERT_ONLY);
289 if (r != Z_OK || tx_strm.avail_in != 0) {
290 rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
291 r, tx_strm.avail_in);
292 exit_cleanup(RERR_STREAMIO);
294 } while (toklen > 0);
299 /* tells us what the receiver is in the middle of doing */
300 static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state;
302 /* for inflating stuff */
303 static z_stream rx_strm;
307 /* for decoding runs of tokens */
308 static int32 rx_token;
311 /* Receive a deflated token and inflate it */
312 static int32 recv_deflated_token(int f, char **data)
314 static int init_done;
315 static int32 saved_flag;
320 switch (recv_state) {
323 rx_strm.next_out = NULL;
324 rx_strm.zalloc = NULL;
325 rx_strm.zfree = NULL;
326 if (inflateInit2(&rx_strm, -15) != Z_OK) {
327 rprintf(FERROR, "inflate init failed\n");
328 exit_cleanup(RERR_STREAMIO);
330 if (!(cbuf = new_array(char, MAX_DATA_COUNT))
331 || !(dbuf = new_array(char, AVAIL_OUT_SIZE(CHUNK_SIZE))))
332 out_of_memory("recv_deflated_token");
335 inflateReset(&rx_strm);
344 flag = saved_flag & 0xff;
348 if ((flag & 0xC0) == DEFLATED_DATA) {
349 n = ((flag & 0x3f) << 8) + read_byte(f);
350 read_buf(f, cbuf, n);
351 rx_strm.next_in = (Bytef *)cbuf;
352 rx_strm.avail_in = n;
353 recv_state = r_inflating;
356 if (recv_state == r_inflated) {
357 /* check previous inflated stuff ended correctly */
358 rx_strm.avail_in = 0;
359 rx_strm.next_out = (Bytef *)dbuf;
360 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
361 r = inflate(&rx_strm, Z_SYNC_FLUSH);
362 n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
364 * Z_BUF_ERROR just means no progress was
365 * made, i.e. the decompressor didn't have
366 * any pending output for us.
368 if (r != Z_OK && r != Z_BUF_ERROR) {
369 rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
371 exit_cleanup(RERR_STREAMIO);
373 if (n != 0 && r != Z_BUF_ERROR) {
374 /* have to return some more data and
375 save the flag for later. */
376 saved_flag = flag + 0x10000;
381 * At this point the decompressor should
382 * be expecting to see the 0, 0, ff, ff bytes.
384 if (!inflateSyncPoint(&rx_strm)) {
385 rprintf(FERROR, "decompressor lost sync!\n");
386 exit_cleanup(RERR_STREAMIO);
388 rx_strm.avail_in = 4;
389 rx_strm.next_in = (Bytef *)cbuf;
390 cbuf[0] = cbuf[1] = 0;
391 cbuf[2] = cbuf[3] = 0xff;
392 inflate(&rx_strm, Z_SYNC_FLUSH);
395 if (flag == END_FLAG) {
396 /* that's all folks */
401 /* here we have a token of some kind */
402 if (flag & TOKEN_REL) {
403 rx_token += flag & 0x3f;
406 rx_token = read_int(f);
408 rx_run = read_byte(f);
409 rx_run += read_byte(f) << 8;
410 recv_state = r_running;
412 return -1 - rx_token;
415 rx_strm.next_out = (Bytef *)dbuf;
416 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
417 r = inflate(&rx_strm, Z_NO_FLUSH);
418 n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
420 rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
421 exit_cleanup(RERR_STREAMIO);
423 if (rx_strm.avail_in == 0)
424 recv_state = r_inflated;
435 return -1 - rx_token;
441 * put the data corresponding to a token that we've just returned
442 * from recv_deflated_token into the decompressor's history buffer.
444 static void see_deflate_token(char *buf, int32 len)
448 unsigned char hdr[5];
450 rx_strm.avail_in = 0;
454 if (rx_strm.avail_in == 0 && len != 0) {
456 /* Give it a fake stored-block header. */
457 rx_strm.next_in = (Bytef *)hdr;
458 rx_strm.avail_in = 5;
463 hdr[2] = blklen >> 8;
467 rx_strm.next_in = (Bytef *)buf;
468 rx_strm.avail_in = blklen;
473 rx_strm.next_out = (Bytef *)dbuf;
474 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
475 r = inflate(&rx_strm, Z_SYNC_FLUSH);
477 rprintf(FERROR, "inflate (token) returned %d\n", r);
478 exit_cleanup(RERR_STREAMIO);
480 } while (len || rx_strm.avail_out == 0);
484 * Transmit a verbatim buffer of length @p n followed by a token.
485 * If token == -1 then we have reached EOF
486 * If n == 0 then don't send a buffer
488 void send_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
489 int32 n, int32 toklen)
492 simple_send_token(f, token, buf, offset, n);
494 send_deflated_token(f, token, buf, offset, n, toklen);
499 * receive a token or buffer from the other end. If the reurn value is >0 then
500 * it is a data buffer of that length, and *data will point at the data.
501 * if the return value is -i then it represents token i-1
502 * if the return value is 0 then the end has been reached
504 int32 recv_token(int f, char **data)
508 if (!do_compression) {
509 tok = simple_recv_token(f,data);
511 tok = recv_deflated_token(f, data);
517 * look at the data corresponding to a token, if necessary
519 void see_token(char *data, int32 toklen)
522 see_deflate_token(data, toklen);