| 1 | /* gzread.c contains minimal changes required to be compiled with zlibWrapper: |
| 2 | * - gz_statep was converted to union to work with -Wstrict-aliasing=1 */ |
| 3 | |
| 4 | /* gzread.c -- zlib functions for reading gzip files |
| 5 | * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013, 2016 Mark Adler |
| 6 | * For conditions of distribution and use, see https://www.zlib.net/zlib_license.html |
| 7 | */ |
| 8 | |
| 9 | #include "gzguts.h" |
| 10 | |
| 11 | /* fix for Visual Studio, which doesn't support ssize_t type. |
| 12 | * see https://github.com/facebook/zstd/issues/1800#issuecomment-545945050 */ |
| 13 | #if defined(_MSC_VER) && !defined(ssize_t) |
| 14 | # include <BaseTsd.h> |
| 15 | typedef SSIZE_T ssize_t; |
| 16 | #endif |
| 17 | |
| 18 | |
| 19 | /* Local functions */ |
| 20 | local int gz_load _Z_OF((gz_statep, unsigned char *, unsigned, unsigned *)); |
| 21 | local int gz_avail _Z_OF((gz_statep)); |
| 22 | local int gz_look _Z_OF((gz_statep)); |
| 23 | local int gz_decomp _Z_OF((gz_statep)); |
| 24 | local int gz_fetch _Z_OF((gz_statep)); |
| 25 | local int gz_skip _Z_OF((gz_statep, z_off64_t)); |
| 26 | local z_size_t gz_read _Z_OF((gz_statep, voidp, z_size_t)); |
| 27 | |
| 28 | /* Use read() to load a buffer -- return -1 on error, otherwise 0. Read from |
| 29 | state.state->fd, and update state.state->eof, state.state->err, and state.state->msg as appropriate. |
| 30 | This function needs to loop on read(), since read() is not guaranteed to |
| 31 | read the number of bytes requested, depending on the type of descriptor. */ |
| 32 | local int gz_load(state, buf, len, have) |
| 33 | gz_statep state; |
| 34 | unsigned char *buf; |
| 35 | unsigned len; |
| 36 | unsigned *have; |
| 37 | { |
| 38 | ssize_t ret; |
| 39 | unsigned get, max = ((unsigned)-1 >> 2) + 1; |
| 40 | |
| 41 | *have = 0; |
| 42 | do { |
| 43 | get = len - *have; |
| 44 | if (get > max) |
| 45 | get = max; |
| 46 | ret = read(state.state->fd, buf + *have, get); |
| 47 | if (ret <= 0) |
| 48 | break; |
| 49 | *have += (unsigned)ret; |
| 50 | } while (*have < len); |
| 51 | if (ret < 0) { |
| 52 | gz_error(state, Z_ERRNO, zstrerror()); |
| 53 | return -1; |
| 54 | } |
| 55 | if (ret == 0) |
| 56 | state.state->eof = 1; |
| 57 | return 0; |
| 58 | } |
| 59 | |
| 60 | /* Load up input buffer and set eof flag if last data loaded -- return -1 on |
| 61 | error, 0 otherwise. Note that the eof flag is set when the end of the input |
| 62 | file is reached, even though there may be unused data in the buffer. Once |
| 63 | that data has been used, no more attempts will be made to read the file. |
| 64 | If strm->avail_in != 0, then the current data is moved to the beginning of |
| 65 | the input buffer, and then the remainder of the buffer is loaded with the |
| 66 | available data from the input file. */ |
| 67 | local int gz_avail(state) |
| 68 | gz_statep state; |
| 69 | { |
| 70 | unsigned got; |
| 71 | z_streamp strm = &(state.state->strm); |
| 72 | |
| 73 | if (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR) |
| 74 | return -1; |
| 75 | if (state.state->eof == 0) { |
| 76 | if (strm->avail_in) { /* copy what's there to the start */ |
| 77 | unsigned char *p = state.state->in; |
| 78 | unsigned const char *q = strm->next_in; |
| 79 | unsigned n = strm->avail_in; |
| 80 | do { |
| 81 | *p++ = *q++; |
| 82 | } while (--n); |
| 83 | } |
| 84 | if (gz_load(state, state.state->in + strm->avail_in, |
| 85 | state.state->size - strm->avail_in, &got) == -1) |
| 86 | return -1; |
| 87 | strm->avail_in += got; |
| 88 | strm->next_in = state.state->in; |
| 89 | } |
| 90 | return 0; |
| 91 | } |
| 92 | |
| 93 | /* Look for gzip header, set up for inflate or copy. state.state->x.have must be 0. |
| 94 | If this is the first time in, allocate required memory. state.state->how will be |
| 95 | left unchanged if there is no more input data available, will be set to COPY |
| 96 | if there is no gzip header and direct copying will be performed, or it will |
| 97 | be set to GZIP for decompression. If direct copying, then leftover input |
| 98 | data from the input buffer will be copied to the output buffer. In that |
| 99 | case, all further file reads will be directly to either the output buffer or |
| 100 | a user buffer. If decompressing, the inflate state will be initialized. |
| 101 | gz_look() will return 0 on success or -1 on failure. */ |
| 102 | local int gz_look(state) |
| 103 | gz_statep state; |
| 104 | { |
| 105 | z_streamp strm = &(state.state->strm); |
| 106 | |
| 107 | /* allocate read buffers and inflate memory */ |
| 108 | if (state.state->size == 0) { |
| 109 | /* allocate buffers */ |
| 110 | state.state->in = (unsigned char *)malloc(state.state->want); |
| 111 | state.state->out = (unsigned char *)malloc(state.state->want << 1); |
| 112 | if (state.state->in == NULL || state.state->out == NULL) { |
| 113 | free(state.state->out); |
| 114 | free(state.state->in); |
| 115 | gz_error(state, Z_MEM_ERROR, "out of memory"); |
| 116 | return -1; |
| 117 | } |
| 118 | state.state->size = state.state->want; |
| 119 | |
| 120 | /* allocate inflate memory */ |
| 121 | state.state->strm.zalloc = Z_NULL; |
| 122 | state.state->strm.zfree = Z_NULL; |
| 123 | state.state->strm.opaque = Z_NULL; |
| 124 | state.state->strm.avail_in = 0; |
| 125 | state.state->strm.next_in = Z_NULL; |
| 126 | if (inflateInit2(&(state.state->strm), 15 + 16) != Z_OK) { /* gunzip */ |
| 127 | free(state.state->out); |
| 128 | free(state.state->in); |
| 129 | state.state->size = 0; |
| 130 | gz_error(state, Z_MEM_ERROR, "out of memory"); |
| 131 | return -1; |
| 132 | } |
| 133 | } |
| 134 | |
| 135 | /* get at least the magic bytes in the input buffer */ |
| 136 | if (strm->avail_in < 2) { |
| 137 | if (gz_avail(state) == -1) |
| 138 | return -1; |
| 139 | if (strm->avail_in == 0) |
| 140 | return 0; |
| 141 | } |
| 142 | |
| 143 | /* look for gzip magic bytes -- if there, do gzip decoding (note: there is |
| 144 | a logical dilemma here when considering the case of a partially written |
| 145 | gzip file, to wit, if a single 31 byte is written, then we cannot tell |
| 146 | whether this is a single-byte file, or just a partially written gzip |
| 147 | file -- for here we assume that if a gzip file is being written, then |
| 148 | the header will be written in a single operation, so that reading a |
| 149 | single byte is sufficient indication that it is not a gzip file) */ |
| 150 | if (strm->avail_in > 1 && |
| 151 | ((strm->next_in[0] == 31 && strm->next_in[1] == 139) /* gz header */ |
| 152 | || (strm->next_in[0] == 40 && strm->next_in[1] == 181))) { /* zstd header */ |
| 153 | inflateReset(strm); |
| 154 | state.state->how = GZIP; |
| 155 | state.state->direct = 0; |
| 156 | return 0; |
| 157 | } |
| 158 | |
| 159 | /* no gzip header -- if we were decoding gzip before, then this is trailing |
| 160 | garbage. Ignore the trailing garbage and finish. */ |
| 161 | if (state.state->direct == 0) { |
| 162 | strm->avail_in = 0; |
| 163 | state.state->eof = 1; |
| 164 | state.state->x.have = 0; |
| 165 | return 0; |
| 166 | } |
| 167 | |
| 168 | /* doing raw i/o, copy any leftover input to output -- this assumes that |
| 169 | the output buffer is larger than the input buffer, which also assures |
| 170 | space for gzungetc() */ |
| 171 | state.state->x.next = state.state->out; |
| 172 | if (strm->avail_in) { |
| 173 | memcpy(state.state->x.next, strm->next_in, strm->avail_in); |
| 174 | state.state->x.have = strm->avail_in; |
| 175 | strm->avail_in = 0; |
| 176 | } |
| 177 | state.state->how = COPY; |
| 178 | state.state->direct = 1; |
| 179 | return 0; |
| 180 | } |
| 181 | |
| 182 | /* Decompress from input to the provided next_out and avail_out in the state. |
| 183 | On return, state.state->x.have and state.state->x.next point to the just decompressed |
| 184 | data. If the gzip stream completes, state.state->how is reset to LOOK to look for |
| 185 | the next gzip stream or raw data, once state.state->x.have is depleted. Returns 0 |
| 186 | on success, -1 on failure. */ |
| 187 | local int gz_decomp(state) |
| 188 | gz_statep state; |
| 189 | { |
| 190 | int ret = Z_OK; |
| 191 | unsigned had; |
| 192 | z_streamp strm = &(state.state->strm); |
| 193 | |
| 194 | /* fill output buffer up to end of deflate stream */ |
| 195 | had = strm->avail_out; |
| 196 | do { |
| 197 | /* get more input for inflate() */ |
| 198 | if (strm->avail_in == 0 && gz_avail(state) == -1) |
| 199 | return -1; |
| 200 | if (strm->avail_in == 0) { |
| 201 | gz_error(state, Z_BUF_ERROR, "unexpected end of file"); |
| 202 | break; |
| 203 | } |
| 204 | |
| 205 | /* decompress and handle errors */ |
| 206 | ret = inflate(strm, Z_NO_FLUSH); |
| 207 | if (ret == Z_STREAM_ERROR || ret == Z_NEED_DICT) { |
| 208 | gz_error(state, Z_STREAM_ERROR, |
| 209 | "internal error: inflate stream corrupt"); |
| 210 | return -1; |
| 211 | } |
| 212 | if (ret == Z_MEM_ERROR) { |
| 213 | gz_error(state, Z_MEM_ERROR, "out of memory"); |
| 214 | return -1; |
| 215 | } |
| 216 | if (ret == Z_DATA_ERROR) { /* deflate stream invalid */ |
| 217 | gz_error(state, Z_DATA_ERROR, |
| 218 | strm->msg == NULL ? "compressed data error" : strm->msg); |
| 219 | return -1; |
| 220 | } |
| 221 | } while (strm->avail_out && ret != Z_STREAM_END); |
| 222 | |
| 223 | /* update available output */ |
| 224 | state.state->x.have = had - strm->avail_out; |
| 225 | state.state->x.next = strm->next_out - state.state->x.have; |
| 226 | |
| 227 | /* if the gzip stream completed successfully, look for another */ |
| 228 | if (ret == Z_STREAM_END) |
| 229 | state.state->how = LOOK; |
| 230 | |
| 231 | /* good decompression */ |
| 232 | return 0; |
| 233 | } |
| 234 | |
| 235 | /* Fetch data and put it in the output buffer. Assumes state.state->x.have is 0. |
| 236 | Data is either copied from the input file or decompressed from the input |
| 237 | file depending on state.state->how. If state.state->how is LOOK, then a gzip header is |
| 238 | looked for to determine whether to copy or decompress. Returns -1 on error, |
| 239 | otherwise 0. gz_fetch() will leave state.state->how as COPY or GZIP unless the |
| 240 | end of the input file has been reached and all data has been processed. */ |
| 241 | local int gz_fetch(state) |
| 242 | gz_statep state; |
| 243 | { |
| 244 | z_streamp strm = &(state.state->strm); |
| 245 | |
| 246 | do { |
| 247 | switch(state.state->how) { |
| 248 | case LOOK: /* -> LOOK, COPY (only if never GZIP), or GZIP */ |
| 249 | if (gz_look(state) == -1) |
| 250 | return -1; |
| 251 | if (state.state->how == LOOK) |
| 252 | return 0; |
| 253 | break; |
| 254 | case COPY: /* -> COPY */ |
| 255 | if (gz_load(state, state.state->out, state.state->size << 1, &(state.state->x.have)) |
| 256 | == -1) |
| 257 | return -1; |
| 258 | state.state->x.next = state.state->out; |
| 259 | return 0; |
| 260 | case GZIP: /* -> GZIP or LOOK (if end of gzip stream) */ |
| 261 | strm->avail_out = state.state->size << 1; |
| 262 | strm->next_out = state.state->out; |
| 263 | if (gz_decomp(state) == -1) |
| 264 | return -1; |
| 265 | } |
| 266 | } while (state.state->x.have == 0 && (!state.state->eof || strm->avail_in)); |
| 267 | return 0; |
| 268 | } |
| 269 | |
| 270 | /* Skip len uncompressed bytes of output. Return -1 on error, 0 on success. */ |
| 271 | local int gz_skip(state, len) |
| 272 | gz_statep state; |
| 273 | z_off64_t len; |
| 274 | { |
| 275 | unsigned n; |
| 276 | |
| 277 | /* skip over len bytes or reach end-of-file, whichever comes first */ |
| 278 | while (len) |
| 279 | /* skip over whatever is in output buffer */ |
| 280 | if (state.state->x.have) { |
| 281 | n = GT_OFF(state.state->x.have) || (z_off64_t)state.state->x.have > len ? |
| 282 | (unsigned)len : state.state->x.have; |
| 283 | state.state->x.have -= n; |
| 284 | state.state->x.next += n; |
| 285 | state.state->x.pos += n; |
| 286 | len -= n; |
| 287 | } |
| 288 | |
| 289 | /* output buffer empty -- return if we're at the end of the input */ |
| 290 | else if (state.state->eof && state.state->strm.avail_in == 0) |
| 291 | break; |
| 292 | |
| 293 | /* need more data to skip -- load up output buffer */ |
| 294 | else { |
| 295 | /* get more output, looking for header if required */ |
| 296 | if (gz_fetch(state) == -1) |
| 297 | return -1; |
| 298 | } |
| 299 | return 0; |
| 300 | } |
| 301 | |
| 302 | /* Read len bytes into buf from file, or less than len up to the end of the |
| 303 | input. Return the number of bytes read. If zero is returned, either the |
| 304 | end of file was reached, or there was an error. state.state->err must be |
| 305 | consulted in that case to determine which. */ |
| 306 | local z_size_t gz_read(state, buf, len) |
| 307 | gz_statep state; |
| 308 | voidp buf; |
| 309 | z_size_t len; |
| 310 | { |
| 311 | z_size_t got; |
| 312 | unsigned n; |
| 313 | |
| 314 | /* if len is zero, avoid unnecessary operations */ |
| 315 | if (len == 0) |
| 316 | return 0; |
| 317 | |
| 318 | /* process a skip request */ |
| 319 | if (state.state->seek) { |
| 320 | state.state->seek = 0; |
| 321 | if (gz_skip(state, state.state->skip) == -1) |
| 322 | return 0; |
| 323 | } |
| 324 | |
| 325 | /* get len bytes to buf, or less than len if at the end */ |
| 326 | got = 0; |
| 327 | do { |
| 328 | /* set n to the maximum amount of len that fits in an unsigned int */ |
| 329 | n = -1; |
| 330 | if (n > len) |
| 331 | n = (unsigned)len; |
| 332 | |
| 333 | /* first just try copying data from the output buffer */ |
| 334 | if (state.state->x.have) { |
| 335 | if (state.state->x.have < n) |
| 336 | n = state.state->x.have; |
| 337 | memcpy(buf, state.state->x.next, n); |
| 338 | state.state->x.next += n; |
| 339 | state.state->x.have -= n; |
| 340 | } |
| 341 | |
| 342 | /* output buffer empty -- return if we're at the end of the input */ |
| 343 | else if (state.state->eof && state.state->strm.avail_in == 0) { |
| 344 | state.state->past = 1; /* tried to read past end */ |
| 345 | break; |
| 346 | } |
| 347 | |
| 348 | /* need output data -- for small len or new stream load up our output |
| 349 | buffer */ |
| 350 | else if (state.state->how == LOOK || n < (state.state->size << 1)) { |
| 351 | /* get more output, looking for header if required */ |
| 352 | if (gz_fetch(state) == -1) |
| 353 | return 0; |
| 354 | continue; /* no progress yet -- go back to copy above */ |
| 355 | /* the copy above assures that we will leave with space in the |
| 356 | output buffer, allowing at least one gzungetc() to succeed */ |
| 357 | } |
| 358 | |
| 359 | /* large len -- read directly into user buffer */ |
| 360 | else if (state.state->how == COPY) { /* read directly */ |
| 361 | if (gz_load(state, (unsigned char *)buf, n, &n) == -1) |
| 362 | return 0; |
| 363 | } |
| 364 | |
| 365 | /* large len -- decompress directly into user buffer */ |
| 366 | else { /* state.state->how == GZIP */ |
| 367 | state.state->strm.avail_out = n; |
| 368 | state.state->strm.next_out = (unsigned char *)buf; |
| 369 | if (gz_decomp(state) == -1) |
| 370 | return 0; |
| 371 | n = state.state->x.have; |
| 372 | state.state->x.have = 0; |
| 373 | } |
| 374 | |
| 375 | /* update progress */ |
| 376 | len -= n; |
| 377 | buf = (char *)buf + n; |
| 378 | got += n; |
| 379 | state.state->x.pos += n; |
| 380 | } while (len); |
| 381 | |
| 382 | /* return number of bytes read into user buffer */ |
| 383 | return got; |
| 384 | } |
| 385 | |
| 386 | /* -- see zlib.h -- */ |
| 387 | int ZEXPORT gzread(file, buf, len) |
| 388 | gzFile file; |
| 389 | voidp buf; |
| 390 | unsigned len; |
| 391 | { |
| 392 | gz_statep state; |
| 393 | |
| 394 | /* get internal structure */ |
| 395 | if (file == NULL) |
| 396 | return -1; |
| 397 | state.file = file; |
| 398 | |
| 399 | /* check that we're reading and that there's no (serious) error */ |
| 400 | if (state.state->mode != GZ_READ || |
| 401 | (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR)) |
| 402 | return -1; |
| 403 | |
| 404 | /* since an int is returned, make sure len fits in one, otherwise return |
| 405 | with an error (this avoids a flaw in the interface) */ |
| 406 | if ((int)len < 0) { |
| 407 | gz_error(state, Z_STREAM_ERROR, "request does not fit in an int"); |
| 408 | return -1; |
| 409 | } |
| 410 | |
| 411 | /* read len or fewer bytes to buf */ |
| 412 | len = (unsigned)gz_read(state, buf, len); |
| 413 | |
| 414 | /* check for an error */ |
| 415 | if (len == 0 && state.state->err != Z_OK && state.state->err != Z_BUF_ERROR) |
| 416 | return -1; |
| 417 | |
| 418 | /* return the number of bytes read (this is assured to fit in an int) */ |
| 419 | return (int)len; |
| 420 | } |
| 421 | |
| 422 | /* -- see zlib.h -- */ |
| 423 | z_size_t ZEXPORT gzfread(buf, size, nitems, file) |
| 424 | voidp buf; |
| 425 | z_size_t size; |
| 426 | z_size_t nitems; |
| 427 | gzFile file; |
| 428 | { |
| 429 | z_size_t len; |
| 430 | gz_statep state; |
| 431 | |
| 432 | /* get internal structure */ |
| 433 | if (file == NULL) |
| 434 | return 0; |
| 435 | state.file = file; |
| 436 | |
| 437 | /* check that we're reading and that there's no (serious) error */ |
| 438 | if (state.state->mode != GZ_READ || |
| 439 | (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR)) |
| 440 | return 0; |
| 441 | |
| 442 | /* compute bytes to read -- error on overflow */ |
| 443 | len = nitems * size; |
| 444 | if (size && len / size != nitems) { |
| 445 | gz_error(state, Z_STREAM_ERROR, "request does not fit in a size_t"); |
| 446 | return 0; |
| 447 | } |
| 448 | |
| 449 | /* read len or fewer bytes to buf, return the number of full items read */ |
| 450 | return len ? gz_read(state, buf, len) / size : 0; |
| 451 | } |
| 452 | |
| 453 | /* -- see zlib.h -- */ |
| 454 | #if ZLIB_VERNUM >= 0x1261 |
| 455 | #ifdef Z_PREFIX_SET |
| 456 | # undef z_gzgetc |
| 457 | #else |
| 458 | # undef gzgetc |
| 459 | #endif |
| 460 | #endif |
| 461 | |
| 462 | #if ZLIB_VERNUM == 0x1260 |
| 463 | # undef gzgetc |
| 464 | #endif |
| 465 | |
| 466 | #if ZLIB_VERNUM <= 0x1250 |
| 467 | ZEXTERN int ZEXPORT gzgetc _Z_OF((gzFile file)); |
| 468 | ZEXTERN int ZEXPORT gzgetc_ _Z_OF((gzFile file)); |
| 469 | #endif |
| 470 | |
| 471 | int ZEXPORT gzgetc(file) |
| 472 | gzFile file; |
| 473 | { |
| 474 | int ret; |
| 475 | unsigned char buf[1]; |
| 476 | gz_statep state; |
| 477 | |
| 478 | /* get internal structure */ |
| 479 | if (file == NULL) |
| 480 | return -1; |
| 481 | state.file = file; |
| 482 | |
| 483 | /* check that we're reading and that there's no (serious) error */ |
| 484 | if (state.state->mode != GZ_READ || |
| 485 | (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR)) |
| 486 | return -1; |
| 487 | |
| 488 | /* try output buffer (no need to check for skip request) */ |
| 489 | if (state.state->x.have) { |
| 490 | state.state->x.have--; |
| 491 | state.state->x.pos++; |
| 492 | return *(state.state->x.next)++; |
| 493 | } |
| 494 | |
| 495 | /* nothing there -- try gz_read() */ |
| 496 | ret = (int)gz_read(state, buf, 1); |
| 497 | return ret < 1 ? -1 : buf[0]; |
| 498 | } |
| 499 | |
| 500 | int ZEXPORT gzgetc_(file) |
| 501 | gzFile file; |
| 502 | { |
| 503 | return gzgetc(file); |
| 504 | } |
| 505 | |
| 506 | /* -- see zlib.h -- */ |
| 507 | int ZEXPORT gzungetc(c, file) |
| 508 | int c; |
| 509 | gzFile file; |
| 510 | { |
| 511 | gz_statep state; |
| 512 | |
| 513 | /* get internal structure */ |
| 514 | if (file == NULL) |
| 515 | return -1; |
| 516 | state.file = file; |
| 517 | |
| 518 | /* check that we're reading and that there's no (serious) error */ |
| 519 | if (state.state->mode != GZ_READ || |
| 520 | (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR)) |
| 521 | return -1; |
| 522 | |
| 523 | /* process a skip request */ |
| 524 | if (state.state->seek) { |
| 525 | state.state->seek = 0; |
| 526 | if (gz_skip(state, state.state->skip) == -1) |
| 527 | return -1; |
| 528 | } |
| 529 | |
| 530 | /* can't push EOF */ |
| 531 | if (c < 0) |
| 532 | return -1; |
| 533 | |
| 534 | /* if output buffer empty, put byte at end (allows more pushing) */ |
| 535 | if (state.state->x.have == 0) { |
| 536 | state.state->x.have = 1; |
| 537 | state.state->x.next = state.state->out + (state.state->size << 1) - 1; |
| 538 | state.state->x.next[0] = (unsigned char)c; |
| 539 | state.state->x.pos--; |
| 540 | state.state->past = 0; |
| 541 | return c; |
| 542 | } |
| 543 | |
| 544 | /* if no room, give up (must have already done a gzungetc()) */ |
| 545 | if (state.state->x.have == (state.state->size << 1)) { |
| 546 | gz_error(state, Z_DATA_ERROR, "out of room to push characters"); |
| 547 | return -1; |
| 548 | } |
| 549 | |
| 550 | /* slide output data if needed and insert byte before existing data */ |
| 551 | if (state.state->x.next == state.state->out) { |
| 552 | unsigned char *src = state.state->out + state.state->x.have; |
| 553 | unsigned char *dest = state.state->out + (state.state->size << 1); |
| 554 | while (src > state.state->out) |
| 555 | *--dest = *--src; |
| 556 | state.state->x.next = dest; |
| 557 | } |
| 558 | state.state->x.have++; |
| 559 | state.state->x.next--; |
| 560 | state.state->x.next[0] = (unsigned char)c; |
| 561 | state.state->x.pos--; |
| 562 | state.state->past = 0; |
| 563 | return c; |
| 564 | } |
| 565 | |
| 566 | /* -- see zlib.h -- */ |
| 567 | char * ZEXPORT gzgets(file, buf, len) |
| 568 | gzFile file; |
| 569 | char *buf; |
| 570 | int len; |
| 571 | { |
| 572 | unsigned left, n; |
| 573 | char *str; |
| 574 | unsigned char *eol; |
| 575 | gz_statep state; |
| 576 | |
| 577 | /* check parameters and get internal structure */ |
| 578 | if (file == NULL || buf == NULL || len < 1) |
| 579 | return NULL; |
| 580 | state.file = file; |
| 581 | |
| 582 | /* check that we're reading and that there's no (serious) error */ |
| 583 | if (state.state->mode != GZ_READ || |
| 584 | (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR)) |
| 585 | return NULL; |
| 586 | |
| 587 | /* process a skip request */ |
| 588 | if (state.state->seek) { |
| 589 | state.state->seek = 0; |
| 590 | if (gz_skip(state, state.state->skip) == -1) |
| 591 | return NULL; |
| 592 | } |
| 593 | |
| 594 | /* copy output bytes up to new line or len - 1, whichever comes first -- |
| 595 | append a terminating zero to the string (we don't check for a zero in |
| 596 | the contents, let the user worry about that) */ |
| 597 | str = buf; |
| 598 | left = (unsigned)len - 1; |
| 599 | if (left) do { |
| 600 | /* assure that something is in the output buffer */ |
| 601 | if (state.state->x.have == 0 && gz_fetch(state) == -1) |
| 602 | return NULL; /* error */ |
| 603 | if (state.state->x.have == 0) { /* end of file */ |
| 604 | state.state->past = 1; /* read past end */ |
| 605 | break; /* return what we have */ |
| 606 | } |
| 607 | |
| 608 | /* look for end-of-line in current output buffer */ |
| 609 | n = state.state->x.have > left ? left : state.state->x.have; |
| 610 | eol = (unsigned char *)memchr(state.state->x.next, '\n', n); |
| 611 | if (eol != NULL) |
| 612 | n = (unsigned)(eol - state.state->x.next) + 1; |
| 613 | |
| 614 | /* copy through end-of-line, or remainder if not found */ |
| 615 | memcpy(buf, state.state->x.next, n); |
| 616 | state.state->x.have -= n; |
| 617 | state.state->x.next += n; |
| 618 | state.state->x.pos += n; |
| 619 | left -= n; |
| 620 | buf += n; |
| 621 | } while (left && eol == NULL); |
| 622 | |
| 623 | /* return terminated string, or if nothing, end of file */ |
| 624 | if (buf == str) |
| 625 | return NULL; |
| 626 | buf[0] = 0; |
| 627 | return str; |
| 628 | } |
| 629 | |
| 630 | /* -- see zlib.h -- */ |
| 631 | int ZEXPORT gzdirect(file) |
| 632 | gzFile file; |
| 633 | { |
| 634 | gz_statep state; |
| 635 | |
| 636 | /* get internal structure */ |
| 637 | if (file == NULL) |
| 638 | return 0; |
| 639 | state.file = file; |
| 640 | |
| 641 | /* if the state is not known, but we can find out, then do so (this is |
| 642 | mainly for right after a gzopen() or gzdopen()) */ |
| 643 | if (state.state->mode == GZ_READ && state.state->how == LOOK && state.state->x.have == 0) |
| 644 | (void)gz_look(state); |
| 645 | |
| 646 | /* return 1 if transparent, 0 if processing a gzip stream */ |
| 647 | return state.state->direct; |
| 648 | } |
| 649 | |
| 650 | /* -- see zlib.h -- */ |
| 651 | int ZEXPORT gzclose_r(file) |
| 652 | gzFile file; |
| 653 | { |
| 654 | int ret, err; |
| 655 | gz_statep state; |
| 656 | |
| 657 | /* get internal structure */ |
| 658 | if (file == NULL) |
| 659 | return Z_STREAM_ERROR; |
| 660 | state.file = file; |
| 661 | |
| 662 | /* check that we're reading */ |
| 663 | if (state.state->mode != GZ_READ) |
| 664 | return Z_STREAM_ERROR; |
| 665 | |
| 666 | /* free memory and close file */ |
| 667 | if (state.state->size) { |
| 668 | inflateEnd(&(state.state->strm)); |
| 669 | free(state.state->out); |
| 670 | free(state.state->in); |
| 671 | } |
| 672 | err = state.state->err == Z_BUF_ERROR ? Z_BUF_ERROR : Z_OK; |
| 673 | gz_error(state, Z_OK, NULL); |
| 674 | free(state.state->path); |
| 675 | ret = close(state.state->fd); |
| 676 | free(state.state); |
| 677 | return ret ? Z_ERRNO : err; |
| 678 | } |