| 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" |
| 21 | #include "lib/zlib.h" |
| 22 | |
| 23 | extern int do_compression; |
| 24 | |
| 25 | |
| 26 | /* non-compressing recv token */ |
| 27 | static int simple_recv_token(int f,char **data) |
| 28 | { |
| 29 | static int residue = 0; |
| 30 | static char *buf = NULL; |
| 31 | int n; |
| 32 | |
| 33 | if (!buf) { |
| 34 | buf = (char *)malloc(CHUNK_SIZE); |
| 35 | if (!buf) out_of_memory("simple_recv_token"); |
| 36 | } |
| 37 | |
| 38 | |
| 39 | if (residue == 0) { |
| 40 | int i = read_int(f); |
| 41 | if (i <= 0) return i; |
| 42 | residue = i; |
| 43 | } |
| 44 | |
| 45 | *data = buf; |
| 46 | n = MIN(CHUNK_SIZE,residue); |
| 47 | residue -= n; |
| 48 | read_buf(f,buf,n); |
| 49 | return n; |
| 50 | } |
| 51 | |
| 52 | |
| 53 | /* non-compressing send token */ |
| 54 | static void simple_send_token(int f,int token, |
| 55 | struct map_struct *buf,int offset,int n) |
| 56 | { |
| 57 | if (n > 0) { |
| 58 | int l = 0; |
| 59 | while (l < n) { |
| 60 | int n1 = MIN(CHUNK_SIZE,n-l); |
| 61 | write_int(f,n1); |
| 62 | write_buf(f,map_ptr(buf,offset+l,n1),n1); |
| 63 | l += n1; |
| 64 | } |
| 65 | } |
| 66 | write_int(f,-(token+1)); |
| 67 | } |
| 68 | |
| 69 | |
| 70 | /* Memory allocation/freeing routines, called by zlib stuff. */ |
| 71 | static void * |
| 72 | z_alloc(void *opaque, uInt items, uInt size) |
| 73 | { |
| 74 | return malloc(items * size); |
| 75 | } |
| 76 | |
| 77 | static void |
| 78 | z_free(void *opaque, void *adrs, uInt nbytes) |
| 79 | { |
| 80 | free(adrs); |
| 81 | } |
| 82 | |
| 83 | /* Flag bytes in compressed stream are encoded as follows: */ |
| 84 | #define END_FLAG 0 /* that's all folks */ |
| 85 | #define TOKEN_LONG 0x20 /* followed by 32-bit token number */ |
| 86 | #define TOKENRUN_LONG 0x21 /* ditto with 16-bit run count */ |
| 87 | #define DEFLATED_DATA 0x40 /* + 6-bit high len, then low len byte */ |
| 88 | #define TOKEN_REL 0x80 /* + 6-bit relative token number */ |
| 89 | #define TOKENRUN_REL 0xc0 /* ditto with 16-bit run count */ |
| 90 | |
| 91 | #define MAX_DATA_COUNT 16383 /* fit 14 bit count into 2 bytes with flags */ |
| 92 | |
| 93 | /* For coding runs of tokens */ |
| 94 | static int last_token = -1; |
| 95 | static int run_start; |
| 96 | static int last_run_end; |
| 97 | |
| 98 | /* Deflation state */ |
| 99 | static z_stream tx_strm; |
| 100 | |
| 101 | /* Output buffer */ |
| 102 | static char *obuf = NULL; |
| 103 | |
| 104 | /* Send a deflated token */ |
| 105 | static void |
| 106 | send_deflated_token(int f, int token, |
| 107 | struct map_struct *buf, int offset, int nb, int toklen) |
| 108 | { |
| 109 | int n, r; |
| 110 | static int init_done; |
| 111 | |
| 112 | if (last_token == -1) { |
| 113 | /* initialization */ |
| 114 | if (!init_done) { |
| 115 | tx_strm.next_in = NULL; |
| 116 | tx_strm.zalloc = z_alloc; |
| 117 | tx_strm.zfree = z_free; |
| 118 | if (deflateInit2(&tx_strm, Z_DEFAULT_COMPRESSION, 8, |
| 119 | -15, 8, Z_DEFAULT_STRATEGY) != Z_OK) { |
| 120 | fprintf(FERROR, "compression init failed\n"); |
| 121 | exit_cleanup(1); |
| 122 | } |
| 123 | if ((obuf = malloc(MAX_DATA_COUNT+2)) == NULL) |
| 124 | out_of_memory("send_deflated_token"); |
| 125 | init_done = 1; |
| 126 | } else |
| 127 | deflateReset(&tx_strm); |
| 128 | run_start = token; |
| 129 | last_run_end = 0; |
| 130 | |
| 131 | } else if (nb != 0 || token != last_token + 1 |
| 132 | || token >= run_start + 65536) { |
| 133 | /* output previous run */ |
| 134 | r = run_start - last_run_end; |
| 135 | n = last_token - run_start; |
| 136 | if (r >= 0 && r <= 63) { |
| 137 | write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r); |
| 138 | } else { |
| 139 | write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG)); |
| 140 | write_int(f, run_start); |
| 141 | } |
| 142 | if (n != 0) { |
| 143 | write_byte(f, n); |
| 144 | write_byte(f, n >> 8); |
| 145 | } |
| 146 | last_run_end = last_token; |
| 147 | run_start = token; |
| 148 | } |
| 149 | |
| 150 | last_token = token; |
| 151 | |
| 152 | if (nb != 0) { |
| 153 | /* deflate the data starting at offset */ |
| 154 | tx_strm.avail_in = 0; |
| 155 | tx_strm.avail_out = 0; |
| 156 | do { |
| 157 | if (tx_strm.avail_in == 0 && nb != 0) { |
| 158 | /* give it some more input */ |
| 159 | n = MIN(nb, CHUNK_SIZE); |
| 160 | tx_strm.next_in = (Bytef *)map_ptr(buf, offset, n); |
| 161 | tx_strm.avail_in = n; |
| 162 | nb -= n; |
| 163 | offset += n; |
| 164 | } |
| 165 | if (tx_strm.avail_out == 0) { |
| 166 | tx_strm.next_out = (Bytef *)(obuf + 2); |
| 167 | tx_strm.avail_out = MAX_DATA_COUNT; |
| 168 | } |
| 169 | r = deflate(&tx_strm, nb? Z_NO_FLUSH: Z_PACKET_FLUSH); |
| 170 | if (r != Z_OK) { |
| 171 | fprintf(FERROR, "deflate returned %d\n", r); |
| 172 | exit_cleanup(1); |
| 173 | } |
| 174 | if (nb == 0 || tx_strm.avail_out == 0) { |
| 175 | n = MAX_DATA_COUNT - tx_strm.avail_out; |
| 176 | if (n > 0) { |
| 177 | obuf[0] = DEFLATED_DATA + (n >> 8); |
| 178 | obuf[1] = n; |
| 179 | write_buf(f, obuf, n+2); |
| 180 | } |
| 181 | } |
| 182 | } while (nb != 0 || tx_strm.avail_out == 0); |
| 183 | } |
| 184 | |
| 185 | if (token != -1) { |
| 186 | /* add the data in the current block to the compressor's |
| 187 | history and hash table */ |
| 188 | tx_strm.next_in = (Bytef *)map_ptr(buf, offset, toklen); |
| 189 | tx_strm.avail_in = toklen; |
| 190 | tx_strm.next_out = NULL; |
| 191 | tx_strm.avail_out = 2 * toklen; |
| 192 | r = deflate(&tx_strm, Z_INSERT_ONLY); |
| 193 | if (r != Z_OK || tx_strm.avail_in != 0) { |
| 194 | fprintf(FERROR, "deflate on token returned %d (%d bytes left)\n", |
| 195 | r, tx_strm.avail_in); |
| 196 | exit_cleanup(1); |
| 197 | } |
| 198 | |
| 199 | } else { |
| 200 | /* end of file - clean up */ |
| 201 | write_byte(f, END_FLAG); |
| 202 | } |
| 203 | } |
| 204 | |
| 205 | |
| 206 | /* tells us what the receiver is in the middle of doing */ |
| 207 | static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state; |
| 208 | |
| 209 | /* for inflating stuff */ |
| 210 | static z_stream rx_strm; |
| 211 | static char *cbuf; |
| 212 | static char *dbuf; |
| 213 | |
| 214 | /* for decoding runs of tokens */ |
| 215 | static int rx_token; |
| 216 | static int rx_run; |
| 217 | |
| 218 | /* Receive a deflated token and inflate it */ |
| 219 | static int |
| 220 | recv_deflated_token(int f, char **data) |
| 221 | { |
| 222 | int n, r, flag; |
| 223 | static int init_done = 0; |
| 224 | static int saved_flag = 0; |
| 225 | |
| 226 | for (;;) { |
| 227 | switch (recv_state) { |
| 228 | case r_init: |
| 229 | if (!init_done) { |
| 230 | rx_strm.next_out = NULL; |
| 231 | rx_strm.zalloc = z_alloc; |
| 232 | rx_strm.zfree = z_free; |
| 233 | if (inflateInit2(&rx_strm, -15) != Z_OK) { |
| 234 | fprintf(FERROR, "inflate init failed\n"); |
| 235 | exit_cleanup(1); |
| 236 | } |
| 237 | if ((cbuf = malloc(MAX_DATA_COUNT)) == NULL |
| 238 | || (dbuf = malloc(CHUNK_SIZE)) == NULL) |
| 239 | out_of_memory("recv_deflated_token"); |
| 240 | init_done = 1; |
| 241 | } else { |
| 242 | inflateReset(&rx_strm); |
| 243 | } |
| 244 | recv_state = r_idle; |
| 245 | rx_token = 0; |
| 246 | break; |
| 247 | |
| 248 | case r_idle: |
| 249 | case r_inflated: |
| 250 | if (saved_flag) { |
| 251 | flag = saved_flag & 0xff; |
| 252 | saved_flag = 0; |
| 253 | } else |
| 254 | flag = read_byte(f); |
| 255 | if ((flag & 0xC0) == DEFLATED_DATA) { |
| 256 | n = ((flag & 0x3f) << 8) + read_byte(f); |
| 257 | read_buf(f, cbuf, n); |
| 258 | rx_strm.next_in = (Bytef *)cbuf; |
| 259 | rx_strm.avail_in = n; |
| 260 | recv_state = r_inflating; |
| 261 | break; |
| 262 | } |
| 263 | if (recv_state == r_inflated) { |
| 264 | /* check previous inflated stuff ended correctly */ |
| 265 | rx_strm.avail_in = 0; |
| 266 | rx_strm.next_out = (Bytef *)dbuf; |
| 267 | rx_strm.avail_out = CHUNK_SIZE; |
| 268 | r = inflate(&rx_strm, Z_PACKET_FLUSH); |
| 269 | n = CHUNK_SIZE - rx_strm.avail_out; |
| 270 | if (r != Z_OK) { |
| 271 | fprintf(FERROR, "inflate flush returned %d (%d bytes)\n", |
| 272 | r, n); |
| 273 | exit_cleanup(1); |
| 274 | } |
| 275 | if (n != 0) { |
| 276 | /* have to return some more data and |
| 277 | save the flag for later. */ |
| 278 | saved_flag = flag + 0x10000; |
| 279 | if (rx_strm.avail_out != 0) |
| 280 | recv_state = r_idle; |
| 281 | *data = dbuf; |
| 282 | return n; |
| 283 | } |
| 284 | recv_state = r_idle; |
| 285 | } |
| 286 | if (flag == END_FLAG) { |
| 287 | /* that's all folks */ |
| 288 | recv_state = r_init; |
| 289 | return 0; |
| 290 | } |
| 291 | |
| 292 | /* here we have a token of some kind */ |
| 293 | if (flag & TOKEN_REL) { |
| 294 | rx_token += flag & 0x3f; |
| 295 | flag >>= 6; |
| 296 | } else |
| 297 | rx_token = read_int(f); |
| 298 | if (flag & 1) { |
| 299 | rx_run = read_byte(f); |
| 300 | rx_run += read_byte(f) << 8; |
| 301 | recv_state = r_running; |
| 302 | } |
| 303 | return -1 - rx_token; |
| 304 | |
| 305 | case r_inflating: |
| 306 | rx_strm.next_out = (Bytef *)dbuf; |
| 307 | rx_strm.avail_out = CHUNK_SIZE; |
| 308 | r = inflate(&rx_strm, Z_NO_FLUSH); |
| 309 | n = CHUNK_SIZE - rx_strm.avail_out; |
| 310 | if (r != Z_OK) { |
| 311 | fprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n); |
| 312 | exit_cleanup(1); |
| 313 | } |
| 314 | if (rx_strm.avail_in == 0) |
| 315 | recv_state = r_inflated; |
| 316 | if (n != 0) { |
| 317 | *data = dbuf; |
| 318 | return n; |
| 319 | } |
| 320 | break; |
| 321 | |
| 322 | case r_running: |
| 323 | ++rx_token; |
| 324 | if (--rx_run == 0) |
| 325 | recv_state = r_idle; |
| 326 | return -1 - rx_token; |
| 327 | } |
| 328 | } |
| 329 | } |
| 330 | |
| 331 | /* |
| 332 | * put the data corresponding to a token that we've just returned |
| 333 | * from recv_deflated_token into the decompressor's history buffer. |
| 334 | */ |
| 335 | void |
| 336 | see_deflate_token(char *buf, int len) |
| 337 | { |
| 338 | int r; |
| 339 | |
| 340 | rx_strm.next_in = (Bytef *)buf; |
| 341 | rx_strm.avail_in = len; |
| 342 | r = inflateIncomp(&rx_strm); |
| 343 | if (r != Z_OK) { |
| 344 | fprintf(FERROR, "inflateIncomp returned %d\n", r); |
| 345 | exit_cleanup(1); |
| 346 | } |
| 347 | } |
| 348 | |
| 349 | /* |
| 350 | * transmit a verbatim buffer of length n followed by a token |
| 351 | * If token == -1 then we have reached EOF |
| 352 | * If n == 0 then don't send a buffer |
| 353 | */ |
| 354 | void send_token(int f,int token,struct map_struct *buf,int offset, |
| 355 | int n,int toklen) |
| 356 | { |
| 357 | if (!do_compression) { |
| 358 | simple_send_token(f,token,buf,offset,n); |
| 359 | } else { |
| 360 | send_deflated_token(f, token, buf, offset, n, toklen); |
| 361 | } |
| 362 | } |
| 363 | |
| 364 | |
| 365 | /* |
| 366 | * receive a token or buffer from the other end. If the reurn value is >0 then |
| 367 | * it is a data buffer of that length, and *data will point at the data. |
| 368 | * if the return value is -i then it represents token i-1 |
| 369 | * if the return value is 0 then the end has been reached |
| 370 | */ |
| 371 | int recv_token(int f,char **data) |
| 372 | { |
| 373 | int tok; |
| 374 | |
| 375 | if (!do_compression) { |
| 376 | tok = simple_recv_token(f,data); |
| 377 | } else { |
| 378 | tok = recv_deflated_token(f, data); |
| 379 | } |
| 380 | return tok; |
| 381 | } |
| 382 | |
| 383 | /* |
| 384 | * look at the data corresponding to a token, if necessary |
| 385 | */ |
| 386 | void see_token(char *data, int toklen) |
| 387 | { |
| 388 | if (do_compression) |
| 389 | see_deflate_token(data, toklen); |
| 390 | } |