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      1 /*
      2   LZ4io.c - LZ4 File/Stream Interface
      3   Copyright (C) Yann Collet 2011-2014
      4   GPL v2 License
      5 
      6   This program is free software; you can redistribute it and/or modify
      7   it under the terms of the GNU General Public License as published by
      8   the Free Software Foundation; either version 2 of the License, or
      9   (at your option) any later version.
     10 
     11   This program is distributed in the hope that it will be useful,
     12   but WITHOUT ANY WARRANTY; without even the implied warranty of
     13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     14   GNU General Public License for more details.
     15 
     16   You should have received a copy of the GNU General Public License along
     17   with this program; if not, write to the Free Software Foundation, Inc.,
     18   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
     19 
     20   You can contact the author at :
     21   - LZ4 source repository : http://code.google.com/p/lz4/
     22   - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
     23 */
     24 /*
     25   Note : this is stand-alone program.
     26   It is not part of LZ4 compression library, it is a user code of the LZ4 library.
     27   - The license of LZ4 library is BSD.
     28   - The license of xxHash library is BSD.
     29   - The license of this source file is GPLv2.
     30 */
     31 
     32 /**************************************
     33 *  Compiler Options
     34 ***************************************/
     35 #ifdef _MSC_VER    /* Visual Studio */
     36 #  define _CRT_SECURE_NO_WARNINGS
     37 #  define _CRT_SECURE_NO_DEPRECATE     /* VS2005 */
     38 #  pragma warning(disable : 4127)      /* disable: C4127: conditional expression is constant */
     39 #endif
     40 
     41 #define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
     42 #ifdef __GNUC__
     43 #  pragma GCC diagnostic ignored "-Wmissing-braces"   /* GCC bug 53119 : doesn't accept { 0 } as initializer (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53119) */
     44 #  pragma GCC diagnostic ignored "-Wmissing-field-initializers"   /* GCC bug 53119 : doesn't accept { 0 } as initializer (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53119) */
     45 #endif
     46 
     47 #define _LARGE_FILES           /* Large file support on 32-bits AIX */
     48 #define _FILE_OFFSET_BITS 64   /* Large file support on 32-bits unix */
     49 #define _POSIX_SOURCE 1        /* for fileno() within <stdio.h> on unix */
     50 
     51 
     52 /****************************
     53 *  Includes
     54 *****************************/
     55 #include <stdio.h>    /* fprintf, fopen, fread, _fileno, stdin, stdout */
     56 #include <stdlib.h>   /* malloc, free */
     57 #include <string.h>   /* strcmp, strlen */
     58 #include <time.h>     /* clock */
     59 #include "lz4io.h"
     60 #include "lz4.h"      /* still required for legacy format */
     61 #include "lz4hc.h"    /* still required for legacy format */
     62 #include "lz4frame.h"
     63 
     64 
     65 /****************************
     66 *  OS-specific Includes
     67 *****************************/
     68 #if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(_WIN32) || defined(__CYGWIN__)
     69 #  include <fcntl.h>   /* _O_BINARY */
     70 #  include <io.h>      /* _setmode, _isatty */
     71 #  ifdef __MINGW32__
     72    int _fileno(FILE *stream);   /* MINGW somehow forgets to include this windows declaration into <stdio.h> */
     73 #  endif
     74 #  define SET_BINARY_MODE(file) _setmode(_fileno(file), _O_BINARY)
     75 #  define IS_CONSOLE(stdStream) _isatty(_fileno(stdStream))
     76 #else
     77 #  include <unistd.h>  /* isatty */
     78 #  define SET_BINARY_MODE(file)
     79 #  define IS_CONSOLE(stdStream) isatty(fileno(stdStream))
     80 #endif
     81 
     82 
     83 /****************************
     84 *  Constants
     85 *****************************/
     86 #define KB *(1 <<10)
     87 #define MB *(1 <<20)
     88 #define GB *(1U<<30)
     89 
     90 #define _1BIT  0x01
     91 #define _2BITS 0x03
     92 #define _3BITS 0x07
     93 #define _4BITS 0x0F
     94 #define _8BITS 0xFF
     95 
     96 #define MAGICNUMBER_SIZE   4
     97 #define LZ4S_MAGICNUMBER   0x184D2204
     98 #define LZ4S_SKIPPABLE0    0x184D2A50
     99 #define LZ4S_SKIPPABLEMASK 0xFFFFFFF0
    100 #define LEGACY_MAGICNUMBER 0x184C2102
    101 
    102 #define CACHELINE 64
    103 #define LEGACY_BLOCKSIZE   (8 MB)
    104 #define MIN_STREAM_BUFSIZE (192 KB)
    105 #define LZ4S_BLOCKSIZEID_DEFAULT 7
    106 #define LZ4S_CHECKSUM_SEED 0
    107 #define LZ4S_EOS 0
    108 #define LZ4S_MAXHEADERSIZE (MAGICNUMBER_SIZE+2+8+4+1)
    109 
    110 
    111 /**************************************
    112 *  Macros
    113 ***************************************/
    114 #define DISPLAY(...)         fprintf(stderr, __VA_ARGS__)
    115 #define DISPLAYLEVEL(l, ...) if (displayLevel>=l) { DISPLAY(__VA_ARGS__); }
    116 #define DISPLAYUPDATE(l, ...) if (displayLevel>=l) { \
    117             if ((LZ4IO_GetMilliSpan(g_time) > refreshRate) || (displayLevel>=4)) \
    118             { g_time = clock(); DISPLAY(__VA_ARGS__); \
    119             if (displayLevel>=4) fflush(stdout); } }
    120 static const unsigned refreshRate = 150;
    121 static clock_t g_time = 0;
    122 
    123 
    124 /**************************************
    125 *  Local Parameters
    126 ***************************************/
    127 static int displayLevel = 0;   /* 0 : no display  ; 1: errors  ; 2 : + result + interaction + warnings ; 3 : + progression; 4 : + information */
    128 static int overwrite = 1;
    129 static int globalBlockSizeId = LZ4S_BLOCKSIZEID_DEFAULT;
    130 static int blockChecksum = 0;
    131 static int streamChecksum = 1;
    132 static int blockIndependence = 1;
    133 
    134 static const int minBlockSizeID = 4;
    135 static const int maxBlockSizeID = 7;
    136 
    137 
    138 /**************************************
    139 *  Exceptions
    140 ***************************************/
    141 #define DEBUG 0
    142 #define DEBUGOUTPUT(...) if (DEBUG) DISPLAY(__VA_ARGS__);
    143 #define EXM_THROW(error, ...)                                             \
    144 {                                                                         \
    145     DEBUGOUTPUT("Error defined at %s, line %i : \n", __FILE__, __LINE__); \
    146     DISPLAYLEVEL(1, "Error %i : ", error);                                \
    147     DISPLAYLEVEL(1, __VA_ARGS__);                                         \
    148     DISPLAYLEVEL(1, "\n");                                                \
    149     exit(error);                                                          \
    150 }
    151 
    152 
    153 /**************************************
    154 *  Version modifiers
    155 ***************************************/
    156 #define EXTENDED_ARGUMENTS
    157 #define EXTENDED_HELP
    158 #define EXTENDED_FORMAT
    159 #define DEFAULT_COMPRESSOR   compress_file
    160 #define DEFAULT_DECOMPRESSOR decodeLZ4S
    161 
    162 
    163 /* ************************************************** */
    164 /* ****************** Parameters ******************** */
    165 /* ************************************************** */
    166 
    167 /* Default setting : overwrite = 1; return : overwrite mode (0/1) */
    168 int LZ4IO_setOverwrite(int yes)
    169 {
    170    overwrite = (yes!=0);
    171    return overwrite;
    172 }
    173 
    174 /* blockSizeID : valid values : 4-5-6-7 */
    175 int LZ4IO_setBlockSizeID(int bsid)
    176 {
    177     static const int blockSizeTable[] = { 64 KB, 256 KB, 1 MB, 4 MB };
    178     if ((bsid < minBlockSizeID) || (bsid > maxBlockSizeID)) return -1;
    179     globalBlockSizeId = bsid;
    180     return blockSizeTable[globalBlockSizeId-minBlockSizeID];
    181 }
    182 
    183 int LZ4IO_setBlockMode(LZ4IO_blockMode_t blockMode)
    184 {
    185     blockIndependence = (blockMode == LZ4IO_blockIndependent);
    186     return blockIndependence;
    187 }
    188 
    189 /* Default setting : no checksum */
    190 int LZ4IO_setBlockChecksumMode(int xxhash)
    191 {
    192     blockChecksum = (xxhash != 0);
    193     return blockChecksum;
    194 }
    195 
    196 /* Default setting : checksum enabled */
    197 int LZ4IO_setStreamChecksumMode(int xxhash)
    198 {
    199     streamChecksum = (xxhash != 0);
    200     return streamChecksum;
    201 }
    202 
    203 /* Default setting : 0 (no notification) */
    204 int LZ4IO_setNotificationLevel(int level)
    205 {
    206     displayLevel = level;
    207     return displayLevel;
    208 }
    209 
    210 static unsigned LZ4IO_GetMilliSpan(clock_t nPrevious)
    211 {
    212     clock_t nCurrent = clock();
    213     unsigned nSpan = (unsigned)(((nCurrent - nPrevious) * 1000) / CLOCKS_PER_SEC);
    214     return nSpan;
    215 }
    216 
    217 
    218 /* ************************************************************************ */
    219 /* ********************** LZ4 File / Pipe compression ********************* */
    220 /* ************************************************************************ */
    221 
    222 static int          LZ4S_GetBlockSize_FromBlockId (int id) { return (1 << (8 + (2 * id))); }
    223 static int          LZ4S_isSkippableMagicNumber(unsigned int magic) { return (magic & LZ4S_SKIPPABLEMASK) == LZ4S_SKIPPABLE0; }
    224 
    225 
    226 static int get_fileHandle(char* input_filename, char* output_filename, FILE** pfinput, FILE** pfoutput)
    227 {
    228 
    229     if (!strcmp (input_filename, stdinmark))
    230     {
    231         DISPLAYLEVEL(4,"Using stdin for input\n");
    232         *pfinput = stdin;
    233         SET_BINARY_MODE(stdin);
    234     }
    235     else
    236     {
    237         *pfinput = fopen(input_filename, "rb");
    238     }
    239 
    240     if (!strcmp (output_filename, stdoutmark))
    241     {
    242         DISPLAYLEVEL(4,"Using stdout for output\n");
    243         *pfoutput = stdout;
    244         SET_BINARY_MODE(stdout);
    245     }
    246     else
    247     {
    248         /* Check if destination file already exists */
    249         *pfoutput=0;
    250         if (output_filename != nulmark) *pfoutput = fopen( output_filename, "rb" );
    251         if (*pfoutput!=0)
    252         {
    253             fclose(*pfoutput);
    254             if (!overwrite)
    255             {
    256                 char ch;
    257                 DISPLAYLEVEL(2, "Warning : %s already exists\n", output_filename);
    258                 DISPLAYLEVEL(2, "Overwrite ? (Y/N) : ");
    259                 if (displayLevel <= 1) EXM_THROW(11, "Operation aborted : %s already exists", output_filename);   /* No interaction possible */
    260                 ch = (char)getchar();
    261                 if ((ch!='Y') && (ch!='y')) EXM_THROW(11, "Operation aborted : %s already exists", output_filename);
    262             }
    263         }
    264         *pfoutput = fopen( output_filename, "wb" );
    265     }
    266 
    267     if ( *pfinput==0 ) EXM_THROW(12, "Pb opening %s", input_filename);
    268     if ( *pfoutput==0) EXM_THROW(13, "Pb opening %s", output_filename);
    269 
    270     return 0;
    271 }
    272 
    273 
    274 
    275 
    276 /***************************************
    277  *   Legacy Compression
    278  * *************************************/
    279 
    280 /* unoptimized version; solves endianess & alignment issues */
    281 static void LZ4IO_writeLE32 (void* p, unsigned value32)
    282 {
    283     unsigned char* dstPtr = p;
    284     dstPtr[0] = (unsigned char)value32;
    285     dstPtr[1] = (unsigned char)(value32 >> 8);
    286     dstPtr[2] = (unsigned char)(value32 >> 16);
    287     dstPtr[3] = (unsigned char)(value32 >> 24);
    288 }
    289 
    290 /* LZ4IO_compressFilename_Legacy :
    291  * This function is intentionally "hidden" (not published in .h)
    292  * It generates compressed streams using the old 'legacy' format */
    293 int LZ4IO_compressFilename_Legacy(char* input_filename, char* output_filename, int compressionlevel)
    294 {
    295     int (*compressionFunction)(const char*, char*, int);
    296     unsigned long long filesize = 0;
    297     unsigned long long compressedfilesize = MAGICNUMBER_SIZE;
    298     char* in_buff;
    299     char* out_buff;
    300     FILE* finput;
    301     FILE* foutput;
    302     clock_t start, end;
    303     size_t sizeCheck;
    304 
    305 
    306     /* Init */
    307     start = clock();
    308     if (compressionlevel < 3) compressionFunction = LZ4_compress; else compressionFunction = LZ4_compressHC;
    309 
    310     get_fileHandle(input_filename, output_filename, &finput, &foutput);
    311     if ((displayLevel==2) && (compressionlevel==1)) displayLevel=3;
    312 
    313     /* Allocate Memory */
    314     in_buff = (char*)malloc(LEGACY_BLOCKSIZE);
    315     out_buff = (char*)malloc(LZ4_compressBound(LEGACY_BLOCKSIZE));
    316     if (!in_buff || !out_buff) EXM_THROW(21, "Allocation error : not enough memory");
    317 
    318     /* Write Archive Header */
    319     LZ4IO_writeLE32(out_buff, LEGACY_MAGICNUMBER);
    320     sizeCheck = fwrite(out_buff, 1, MAGICNUMBER_SIZE, foutput);
    321     if (sizeCheck!=MAGICNUMBER_SIZE) EXM_THROW(22, "Write error : cannot write header");
    322 
    323     /* Main Loop */
    324     while (1)
    325     {
    326         unsigned int outSize;
    327         /* Read Block */
    328         int inSize = (int) fread(in_buff, (size_t)1, (size_t)LEGACY_BLOCKSIZE, finput);
    329         if( inSize<=0 ) break;
    330         filesize += inSize;
    331 
    332         /* Compress Block */
    333         outSize = compressionFunction(in_buff, out_buff+4, inSize);
    334         compressedfilesize += outSize+4;
    335         DISPLAYUPDATE(3, "\rRead : %i MB  ==> %.2f%%   ", (int)(filesize>>20), (double)compressedfilesize/filesize*100);
    336 
    337         /* Write Block */
    338         LZ4IO_writeLE32(out_buff, outSize);
    339         sizeCheck = fwrite(out_buff, 1, outSize+4, foutput);
    340         if (sizeCheck!=(size_t)(outSize+4)) EXM_THROW(23, "Write error : cannot write compressed block");
    341     }
    342 
    343     /* Status */
    344     end = clock();
    345     DISPLAYLEVEL(2, "\r%79s\r", "");
    346     DISPLAYLEVEL(2,"Compressed %llu bytes into %llu bytes ==> %.2f%%\n",
    347         (unsigned long long) filesize, (unsigned long long) compressedfilesize, (double)compressedfilesize/filesize*100);
    348     {
    349         double seconds = (double)(end - start)/CLOCKS_PER_SEC;
    350         DISPLAYLEVEL(4,"Done in %.2f s ==> %.2f MB/s\n", seconds, (double)filesize / seconds / 1024 / 1024);
    351     }
    352 
    353     /* Close & Free */
    354     free(in_buff);
    355     free(out_buff);
    356     fclose(finput);
    357     fclose(foutput);
    358 
    359     return 0;
    360 }
    361 
    362 
    363 /***********************************************
    364  *   Compression using Frame format
    365  * ********************************************/
    366 
    367 int LZ4IO_compressFilename(char* input_filename, char* output_filename, int compressionLevel)
    368 {
    369     unsigned long long filesize = 0;
    370     unsigned long long compressedfilesize = 0;
    371     char* in_buff;
    372     char* out_buff;
    373     FILE* finput;
    374     FILE* foutput;
    375     clock_t start, end;
    376     int blockSize;
    377     size_t sizeCheck, headerSize, readSize, outBuffSize;
    378     LZ4F_compressionContext_t ctx;
    379     LZ4F_errorCode_t errorCode;
    380     LZ4F_preferences_t prefs = {0};
    381 
    382 
    383     /* Init */
    384     start = clock();
    385     if ((displayLevel==2) && (compressionLevel>=3)) displayLevel=3;
    386     errorCode = LZ4F_createCompressionContext(&ctx, LZ4F_VERSION);
    387     if (LZ4F_isError(errorCode)) EXM_THROW(30, "Allocation error : can't create LZ4F context : %s", LZ4F_getErrorName(errorCode));
    388     get_fileHandle(input_filename, output_filename, &finput, &foutput);
    389     blockSize = LZ4S_GetBlockSize_FromBlockId (globalBlockSizeId);
    390 
    391     /* Set compression parameters */
    392     prefs.autoFlush = 1;
    393     prefs.compressionLevel = compressionLevel;
    394     prefs.frameInfo.blockMode = blockIndependence;
    395     prefs.frameInfo.blockSizeID = globalBlockSizeId;
    396     prefs.frameInfo.contentChecksumFlag = streamChecksum;
    397 
    398     /* Allocate Memory */
    399     in_buff  = (char*)malloc(blockSize);
    400     outBuffSize = LZ4F_compressBound(blockSize, &prefs);
    401     out_buff = (char*)malloc(outBuffSize);
    402     if (!in_buff || !out_buff) EXM_THROW(31, "Allocation error : not enough memory");
    403 
    404     /* Write Archive Header */
    405     headerSize = LZ4F_compressBegin(ctx, out_buff, outBuffSize, &prefs);
    406     if (LZ4F_isError(headerSize)) EXM_THROW(32, "File header generation failed : %s", LZ4F_getErrorName(headerSize));
    407     sizeCheck = fwrite(out_buff, 1, headerSize, foutput);
    408     if (sizeCheck!=headerSize) EXM_THROW(33, "Write error : cannot write header");
    409     compressedfilesize += headerSize;
    410 
    411     /* read first block */
    412     readSize = fread(in_buff, (size_t)1, (size_t)blockSize, finput);
    413     filesize += readSize;
    414 
    415     /* Main Loop */
    416     while (readSize>0)
    417     {
    418         size_t outSize;
    419 
    420         /* Compress Block */
    421         outSize = LZ4F_compressUpdate(ctx, out_buff, outBuffSize, in_buff, readSize, NULL);
    422         if (LZ4F_isError(outSize)) EXM_THROW(34, "Compression failed : %s", LZ4F_getErrorName(outSize));
    423         compressedfilesize += outSize;
    424         DISPLAYUPDATE(3, "\rRead : %i MB   ==> %.2f%%   ", (int)(filesize>>20), (double)compressedfilesize/filesize*100);
    425 
    426         /* Write Block */
    427         sizeCheck = fwrite(out_buff, 1, outSize, foutput);
    428         if (sizeCheck!=outSize) EXM_THROW(35, "Write error : cannot write compressed block");
    429 
    430         /* Read next block */
    431         readSize = fread(in_buff, (size_t)1, (size_t)blockSize, finput);
    432         filesize += readSize;
    433     }
    434 
    435     /* End of Stream mark */
    436     headerSize = LZ4F_compressEnd(ctx, out_buff, outBuffSize, NULL);
    437     if (LZ4F_isError(headerSize)) EXM_THROW(36, "End of file generation failed : %s", LZ4F_getErrorName(headerSize));
    438 
    439     sizeCheck = fwrite(out_buff, 1, headerSize, foutput);
    440     if (sizeCheck!=headerSize) EXM_THROW(37, "Write error : cannot write end of stream");
    441     compressedfilesize += headerSize;
    442 
    443     /* Close & Free */
    444     free(in_buff);
    445     free(out_buff);
    446     fclose(finput);
    447     fclose(foutput);
    448     errorCode = LZ4F_freeCompressionContext(ctx);
    449     if (LZ4F_isError(errorCode)) EXM_THROW(38, "Error : can't free LZ4F context resource : %s", LZ4F_getErrorName(errorCode));
    450 
    451     /* Final Status */
    452     end = clock();
    453     DISPLAYLEVEL(2, "\r%79s\r", "");
    454     DISPLAYLEVEL(2, "Compressed %llu bytes into %llu bytes ==> %.2f%%\n",
    455         (unsigned long long) filesize, (unsigned long long) compressedfilesize, (double)compressedfilesize/filesize*100);
    456     {
    457         double seconds = (double)(end - start)/CLOCKS_PER_SEC;
    458         DISPLAYLEVEL(4, "Done in %.2f s ==> %.2f MB/s\n", seconds, (double)filesize / seconds / 1024 / 1024);
    459     }
    460 
    461     return 0;
    462 }
    463 
    464 
    465 /* ********************************************************************* */
    466 /* ********************** LZ4 File / Stream decoding ******************* */
    467 /* ********************************************************************* */
    468 
    469 static unsigned LZ4IO_readLE32 (const void* s)
    470 {
    471     const unsigned char* srcPtr = s;
    472     unsigned value32 = srcPtr[0];
    473     value32 += (srcPtr[1]<<8);
    474     value32 += (srcPtr[2]<<16);
    475     value32 += (srcPtr[3]<<24);
    476     return value32;
    477 }
    478 
    479 static unsigned long long decodeLegacyStream(FILE* finput, FILE* foutput)
    480 {
    481     unsigned long long filesize = 0;
    482     char* in_buff;
    483     char* out_buff;
    484 
    485     /* Allocate Memory */
    486     in_buff = (char*)malloc(LZ4_compressBound(LEGACY_BLOCKSIZE));
    487     out_buff = (char*)malloc(LEGACY_BLOCKSIZE);
    488     if (!in_buff || !out_buff) EXM_THROW(51, "Allocation error : not enough memory");
    489 
    490     /* Main Loop */
    491     while (1)
    492     {
    493         int decodeSize;
    494         size_t sizeCheck;
    495         unsigned int blockSize;
    496 
    497         /* Block Size */
    498         sizeCheck = fread(in_buff, 1, 4, finput);
    499         if (sizeCheck==0) break;                   /* Nothing to read : file read is completed */
    500         blockSize = LZ4IO_readLE32(in_buff);       /* Convert to Little Endian */
    501         if (blockSize > LZ4_COMPRESSBOUND(LEGACY_BLOCKSIZE))
    502         {   /* Cannot read next block : maybe new stream ? */
    503             fseek(finput, -4, SEEK_CUR);
    504             break;
    505         }
    506 
    507         /* Read Block */
    508         sizeCheck = fread(in_buff, 1, blockSize, finput);
    509 
    510         /* Decode Block */
    511         decodeSize = LZ4_decompress_safe(in_buff, out_buff, blockSize, LEGACY_BLOCKSIZE);
    512         if (decodeSize < 0) EXM_THROW(52, "Decoding Failed ! Corrupted input detected !");
    513         filesize += decodeSize;
    514 
    515         /* Write Block */
    516         sizeCheck = fwrite(out_buff, 1, decodeSize, foutput);
    517         if (sizeCheck != (size_t)decodeSize) EXM_THROW(53, "Write error : cannot write decoded block into output\n");
    518     }
    519 
    520     /* Free */
    521     free(in_buff);
    522     free(out_buff);
    523 
    524     return filesize;
    525 }
    526 
    527 
    528 static unsigned long long decodeLZ4S(FILE* finput, FILE* foutput)
    529 {
    530     unsigned long long filesize = 0;
    531     char* inBuff;
    532     char* outBuff;
    533 #   define HEADERMAX 20
    534     char  headerBuff[HEADERMAX];
    535     size_t sizeCheck, nextToRead, outBuffSize, inBuffSize;
    536     LZ4F_decompressionContext_t ctx;
    537     LZ4F_errorCode_t errorCode;
    538     LZ4F_frameInfo_t frameInfo;
    539 
    540     /* init */
    541     errorCode = LZ4F_createDecompressionContext(&ctx, LZ4F_VERSION);
    542     if (LZ4F_isError(errorCode)) EXM_THROW(60, "Allocation error : can't create context : %s", LZ4F_getErrorName(errorCode));
    543     LZ4IO_writeLE32(headerBuff, LZ4S_MAGICNUMBER);   /* regenerated here, as it was already read from finput */
    544 
    545     /* Decode stream descriptor */
    546     outBuffSize = 0; inBuffSize = 0; sizeCheck = MAGICNUMBER_SIZE;
    547     nextToRead = LZ4F_decompress(ctx, NULL, &outBuffSize, headerBuff, &sizeCheck, NULL);
    548     if (LZ4F_isError(nextToRead)) EXM_THROW(61, "Decompression error : %s", LZ4F_getErrorName(nextToRead));
    549     if (nextToRead > HEADERMAX) EXM_THROW(62, "Header too large (%i>%i)", (int)nextToRead, HEADERMAX);
    550     sizeCheck = fread(headerBuff, 1, nextToRead, finput);
    551     if (sizeCheck!=nextToRead) EXM_THROW(63, "Read error ");
    552     nextToRead = LZ4F_decompress(ctx, NULL, &outBuffSize, headerBuff, &sizeCheck, NULL);
    553     errorCode = LZ4F_getFrameInfo(ctx, &frameInfo, NULL, &inBuffSize);
    554     if (LZ4F_isError(errorCode)) EXM_THROW(64, "can't decode frame header : %s", LZ4F_getErrorName(errorCode));
    555 
    556     /* Allocate Memory */
    557     outBuffSize = LZ4IO_setBlockSizeID(frameInfo.blockSizeID);
    558     inBuffSize = outBuffSize + 4;
    559     inBuff = (char*)malloc(inBuffSize);
    560     outBuff = (char*)malloc(outBuffSize);
    561     if (!inBuff || !outBuff) EXM_THROW(65, "Allocation error : not enough memory");
    562 
    563     /* Main Loop */
    564     while (nextToRead != 0)
    565     {
    566         size_t decodedBytes = outBuffSize;
    567 
    568         /* Read Block */
    569         sizeCheck = fread(inBuff, 1, nextToRead, finput);
    570         if (sizeCheck!=nextToRead) EXM_THROW(66, "Read error ");
    571 
    572         /* Decode Block */
    573         errorCode = LZ4F_decompress(ctx, outBuff, &decodedBytes, inBuff, &sizeCheck, NULL);
    574         if (LZ4F_isError(errorCode)) EXM_THROW(67, "Decompression error : %s", LZ4F_getErrorName(errorCode));
    575         if (sizeCheck!=nextToRead) EXM_THROW(67, "Synchronization error");
    576         nextToRead = errorCode;
    577         filesize += decodedBytes;
    578 
    579         /* Write Block */
    580         sizeCheck = fwrite(outBuff, 1, decodedBytes, foutput);
    581         if (sizeCheck != decodedBytes) EXM_THROW(68, "Write error : cannot write decoded block\n");
    582     }
    583 
    584     /* Free */
    585     free(inBuff);
    586     free(outBuff);
    587     errorCode = LZ4F_freeDecompressionContext(ctx);
    588     if (LZ4F_isError(errorCode)) EXM_THROW(69, "Error : can't free LZ4F context resource : %s", LZ4F_getErrorName(errorCode));
    589 
    590     return filesize;
    591 }
    592 
    593 
    594 #define ENDOFSTREAM ((unsigned long long)-1)
    595 static unsigned long long selectDecoder( FILE* finput,  FILE* foutput)
    596 {
    597     unsigned char U32store[MAGICNUMBER_SIZE];
    598     unsigned magicNumber, size;
    599     int errorNb;
    600     size_t nbReadBytes;
    601 
    602     /* Check Archive Header */
    603     nbReadBytes = fread(U32store, 1, MAGICNUMBER_SIZE, finput);
    604     if (nbReadBytes==0) return ENDOFSTREAM;                  /* EOF */
    605     if (nbReadBytes != MAGICNUMBER_SIZE) EXM_THROW(40, "Unrecognized header : Magic Number unreadable");
    606     magicNumber = LZ4IO_readLE32(U32store);   /* Little Endian format */
    607     if (LZ4S_isSkippableMagicNumber(magicNumber)) magicNumber = LZ4S_SKIPPABLE0;  /* fold skippable magic numbers */
    608 
    609     switch(magicNumber)
    610     {
    611     case LZ4S_MAGICNUMBER:
    612         return DEFAULT_DECOMPRESSOR(finput, foutput);
    613     case LEGACY_MAGICNUMBER:
    614         DISPLAYLEVEL(4, "Detected : Legacy format \n");
    615         return decodeLegacyStream(finput, foutput);
    616     case LZ4S_SKIPPABLE0:
    617         DISPLAYLEVEL(4, "Skipping detected skippable area \n");
    618         nbReadBytes = fread(U32store, 1, 4, finput);
    619         if (nbReadBytes != 4) EXM_THROW(42, "Stream error : skippable size unreadable");
    620         size = LZ4IO_readLE32(U32store);     /* Little Endian format */
    621         errorNb = fseek(finput, size, SEEK_CUR);
    622         if (errorNb != 0) EXM_THROW(43, "Stream error : cannot skip skippable area");
    623         return selectDecoder(finput, foutput);
    624     EXTENDED_FORMAT;
    625     default:
    626         if (ftell(finput) == MAGICNUMBER_SIZE) EXM_THROW(44,"Unrecognized header : file cannot be decoded");   /* Wrong magic number at the beginning of 1st stream */
    627         DISPLAYLEVEL(2, "Stream followed by unrecognized data\n");
    628         return ENDOFSTREAM;
    629     }
    630 }
    631 
    632 
    633 int LZ4IO_decompressFilename(char* input_filename, char* output_filename)
    634 {
    635     unsigned long long filesize = 0, decodedSize=0;
    636     FILE* finput;
    637     FILE* foutput;
    638     clock_t start, end;
    639 
    640 
    641     /* Init */
    642     start = clock();
    643     get_fileHandle(input_filename, output_filename, &finput, &foutput);
    644 
    645     /* Loop over multiple streams */
    646     do
    647     {
    648         decodedSize = selectDecoder(finput, foutput);
    649         if (decodedSize != ENDOFSTREAM)
    650             filesize += decodedSize;
    651     } while (decodedSize != ENDOFSTREAM);
    652 
    653     /* Final Status */
    654     end = clock();
    655     DISPLAYLEVEL(2, "\r%79s\r", "");
    656     DISPLAYLEVEL(2, "Successfully decoded %llu bytes \n", filesize);
    657     {
    658         double seconds = (double)(end - start)/CLOCKS_PER_SEC;
    659         DISPLAYLEVEL(4, "Done in %.2f s ==> %.2f MB/s\n", seconds, (double)filesize / seconds / 1024 / 1024);
    660     }
    661 
    662     /* Close */
    663     fclose(finput);
    664     fclose(foutput);
    665 
    666     /*  Error status = OK */
    667     return 0;
    668 }
    669 
    670