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); } }
120static const unsigned refreshRate = 150;
121static clock_t g_time = 0;
122
123
124/**************************************
125*  Local Parameters
126***************************************/
127static int displayLevel = 0;   /* 0 : no display  ; 1: errors  ; 2 : + result + interaction + warnings ; 3 : + progression; 4 : + information */
128static int overwrite = 1;
129static int globalBlockSizeId = LZ4S_BLOCKSIZEID_DEFAULT;
130static int blockChecksum = 0;
131static int streamChecksum = 1;
132static int blockIndependence = 1;
133
134static const int minBlockSizeID = 4;
135static 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) */
168int LZ4IO_setOverwrite(int yes)
169{
170   overwrite = (yes!=0);
171   return overwrite;
172}
173
174/* blockSizeID : valid values : 4-5-6-7 */
175int 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
183int LZ4IO_setBlockMode(LZ4IO_blockMode_t blockMode)
184{
185    blockIndependence = (blockMode == LZ4IO_blockIndependent);
186    return blockIndependence;
187}
188
189/* Default setting : no checksum */
190int LZ4IO_setBlockChecksumMode(int xxhash)
191{
192    blockChecksum = (xxhash != 0);
193    return blockChecksum;
194}
195
196/* Default setting : checksum enabled */
197int LZ4IO_setStreamChecksumMode(int xxhash)
198{
199    streamChecksum = (xxhash != 0);
200    return streamChecksum;
201}
202
203/* Default setting : 0 (no notification) */
204int LZ4IO_setNotificationLevel(int level)
205{
206    displayLevel = level;
207    return displayLevel;
208}
209
210static 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
222static int          LZ4S_GetBlockSize_FromBlockId (int id) { return (1 << (8 + (2 * id))); }
223static int          LZ4S_isSkippableMagicNumber(unsigned int magic) { return (magic & LZ4S_SKIPPABLEMASK) == LZ4S_SKIPPABLE0; }
224
225
226static 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 */
281static 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 */
293int 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
367int 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
469static 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
479static 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
528static 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)
595static 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
633int 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