Yann Collet | 394bdd7 | 2017-08-29 09:24:11 -0700 | [diff] [blame] | 1 | /* |
Nick Terrell | ac58c8d | 2020-03-26 15:19:05 -0700 | [diff] [blame] | 2 | * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc. |
Yann Collet | 4ded9e5 | 2016-08-30 10:04:33 -0700 | [diff] [blame] | 3 | * All rights reserved. |
| 4 | * |
Yann Collet | 394bdd7 | 2017-08-29 09:24:11 -0700 | [diff] [blame] | 5 | * This source code is licensed under both the BSD-style license (found in the |
| 6 | * LICENSE file in the root directory of this source tree) and the GPLv2 (found |
| 7 | * in the COPYING file in the root directory of this source tree). |
Yann Collet | 3128e03 | 2017-09-08 00:09:23 -0700 | [diff] [blame] | 8 | * You may select, at your option, one of the above-listed licenses. |
Yann Collet | 4ded9e5 | 2016-08-30 10:04:33 -0700 | [diff] [blame] | 9 | */ |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 10 | |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 11 | |
Nick Terrell | 1d0c170 | 2019-04-05 18:11:17 -0700 | [diff] [blame] | 12 | #include <stdio.h> // fprintf |
| 13 | #include <stdlib.h> // free |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 14 | #include <zstd.h> // presumes zstd library is installed |
Nick Terrell | 1d0c170 | 2019-04-05 18:11:17 -0700 | [diff] [blame] | 15 | #include "common.h" // Helper functions, CHECK(), and CHECK_ZSTD() |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 16 | |
| 17 | static void decompressFile_orDie(const char* fname) |
| 18 | { |
| 19 | FILE* const fin = fopen_orDie(fname, "rb"); |
Yann Collet | 01c1992 | 2016-09-08 19:29:04 +0200 | [diff] [blame] | 20 | size_t const buffInSize = ZSTD_DStreamInSize(); |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 21 | void* const buffIn = malloc_orDie(buffInSize); |
Yann Collet | b94fcc8 | 2016-09-08 19:48:04 +0200 | [diff] [blame] | 22 | FILE* const fout = stdout; |
Yann Collet | 01c1992 | 2016-09-08 19:29:04 +0200 | [diff] [blame] | 23 | size_t const buffOutSize = ZSTD_DStreamOutSize(); /* Guarantee to successfully flush at least one complete compressed block in all circumstances. */ |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 24 | void* const buffOut = malloc_orDie(buffOutSize); |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 25 | |
Nick Terrell | de58910 | 2019-04-01 17:25:26 -0700 | [diff] [blame] | 26 | ZSTD_DCtx* const dctx = ZSTD_createDCtx(); |
| 27 | CHECK(dctx != NULL, "ZSTD_createDCtx() failed!"); |
Yann Collet | 22de81e | 2016-10-28 13:58:31 -0700 | [diff] [blame] | 28 | |
Nick Terrell | de58910 | 2019-04-01 17:25:26 -0700 | [diff] [blame] | 29 | /* This loop assumes that the input file is one or more concatenated zstd |
| 30 | * streams. This example won't work if there is trailing non-zstd data at |
| 31 | * the end, but streaming decompression in general handles this case. |
| 32 | * ZSTD_decompressStream() returns 0 exactly when the frame is completed, |
| 33 | * and doesn't consume input after the frame. |
| 34 | */ |
| 35 | size_t const toRead = buffInSize; |
| 36 | size_t read; |
Jan Kasiak | a821990 | 2019-09-01 15:35:53 -0400 | [diff] [blame] | 37 | size_t lastRet = 0; |
| 38 | int isEmpty = 1; |
Yann Collet | 01c1992 | 2016-09-08 19:29:04 +0200 | [diff] [blame] | 39 | while ( (read = fread_orDie(buffIn, toRead, fin)) ) { |
Jan Kasiak | a821990 | 2019-09-01 15:35:53 -0400 | [diff] [blame] | 40 | isEmpty = 0; |
Yann Collet | 2065879 | 2016-08-17 01:48:43 +0200 | [diff] [blame] | 41 | ZSTD_inBuffer input = { buffIn, read, 0 }; |
Nick Terrell | de58910 | 2019-04-01 17:25:26 -0700 | [diff] [blame] | 42 | /* Given a valid frame, zstd won't consume the last byte of the frame |
| 43 | * until it has flushed all of the decompressed data of the frame. |
| 44 | * Therefore, instead of checking if the return code is 0, we can |
| 45 | * decompress just check if input.pos < input.size. |
| 46 | */ |
Yann Collet | 2065879 | 2016-08-17 01:48:43 +0200 | [diff] [blame] | 47 | while (input.pos < input.size) { |
| 48 | ZSTD_outBuffer output = { buffOut, buffOutSize, 0 }; |
Nick Terrell | de58910 | 2019-04-01 17:25:26 -0700 | [diff] [blame] | 49 | /* The return code is zero if the frame is complete, but there may |
| 50 | * be multiple frames concatenated together. Zstd will automatically |
| 51 | * reset the context when a frame is complete. Still, calling |
| 52 | * ZSTD_DCtx_reset() can be useful to reset the context to a clean |
| 53 | * state, for instance if the last decompression call returned an |
| 54 | * error. |
| 55 | */ |
| 56 | size_t const ret = ZSTD_decompressStream(dctx, &output , &input); |
| 57 | CHECK_ZSTD(ret); |
Yann Collet | 01c1992 | 2016-09-08 19:29:04 +0200 | [diff] [blame] | 58 | fwrite_orDie(buffOut, output.pos, fout); |
Jan Kasiak | a821990 | 2019-09-01 15:35:53 -0400 | [diff] [blame] | 59 | lastRet = ret; |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 60 | } |
| 61 | } |
| 62 | |
Jan Kasiak | a821990 | 2019-09-01 15:35:53 -0400 | [diff] [blame] | 63 | if (isEmpty) { |
| 64 | fprintf(stderr, "input is empty\n"); |
| 65 | exit(1); |
| 66 | } |
| 67 | |
| 68 | if (lastRet != 0) { |
| 69 | /* The last return value from ZSTD_decompressStream did not end on a |
| 70 | * frame, but we reached the end of the file! We assume this is an |
| 71 | * error, and the input was truncated. |
| 72 | */ |
| 73 | fprintf(stderr, "EOF before end of stream: %zu\n", lastRet); |
| 74 | exit(1); |
| 75 | } |
| 76 | |
Nick Terrell | de58910 | 2019-04-01 17:25:26 -0700 | [diff] [blame] | 77 | ZSTD_freeDCtx(dctx); |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 78 | fclose_orDie(fin); |
Yann Collet | 01c1992 | 2016-09-08 19:29:04 +0200 | [diff] [blame] | 79 | fclose_orDie(fout); |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 80 | free(buffIn); |
| 81 | free(buffOut); |
| 82 | } |
| 83 | |
| 84 | |
| 85 | int main(int argc, const char** argv) |
| 86 | { |
| 87 | const char* const exeName = argv[0]; |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 88 | |
| 89 | if (argc!=2) { |
Yann Collet | 264c733 | 2016-09-08 19:39:00 +0200 | [diff] [blame] | 90 | fprintf(stderr, "wrong arguments\n"); |
| 91 | fprintf(stderr, "usage:\n"); |
| 92 | fprintf(stderr, "%s FILE\n", exeName); |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 93 | return 1; |
| 94 | } |
| 95 | |
niXman | 65e2cda | 2017-04-26 13:04:04 +0300 | [diff] [blame] | 96 | const char* const inFilename = argv[1]; |
| 97 | |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 98 | decompressFile_orDie(inFilename); |
Yann Collet | 9f9f1fc | 2016-08-12 18:56:27 +0200 | [diff] [blame] | 99 | return 0; |
| 100 | } |