1/*
2 * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
3 * All rights reserved.
4 *
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).
8 * You may select, at your option, one of the above-listed licenses.
9 */
10
11
12
13/* **************************************
14*  Compiler Warnings
15****************************************/
16#ifdef _MSC_VER
17#  pragma warning(disable : 4127)    /* disable: C4127: conditional expression is constant */
18#endif
19
20
21/*-*************************************
22*  Includes
23***************************************/
24#include "platform.h"       /* Large Files support */
25#include "util.h"           /* UTIL_getFileSize, UTIL_getTotalFileSize */
26#include <stdlib.h>         /* malloc, free */
27#include <string.h>         /* memset */
28#include <stdio.h>          /* fprintf, fopen, ftello64 */
29#include <errno.h>          /* errno */
30
31#include "mem.h"            /* read */
32#include "error_private.h"
33#include "dibio.h"
34
35
36/*-*************************************
37*  Constants
38***************************************/
39#define KB *(1 <<10)
40#define MB *(1 <<20)
41#define GB *(1U<<30)
42
43#define SAMPLESIZE_MAX (128 KB)
44#define MEMMULT 11    /* rough estimation : memory cost to analyze 1 byte of sample */
45#define COVER_MEMMULT 9    /* rough estimation : memory cost to analyze 1 byte of sample */
46static const size_t g_maxMemory = (sizeof(size_t) == 4) ? (2 GB - 64 MB) : ((size_t)(512 MB) << sizeof(size_t));
47
48#define NOISELENGTH 32
49
50
51/*-*************************************
52*  Console display
53***************************************/
54#define DISPLAY(...)         fprintf(stderr, __VA_ARGS__)
55#define DISPLAYLEVEL(l, ...) if (displayLevel>=l) { DISPLAY(__VA_ARGS__); }
56
57static const U64 g_refreshRate = SEC_TO_MICRO / 6;
58static UTIL_time_t g_displayClock = UTIL_TIME_INITIALIZER;
59
60#define DISPLAYUPDATE(l, ...) { if (displayLevel>=l) { \
61            if ((UTIL_clockSpanMicro(g_displayClock) > g_refreshRate) || (displayLevel>=4)) \
62            { g_displayClock = UTIL_getTime(); DISPLAY(__VA_ARGS__); \
63            if (displayLevel>=4) fflush(stderr); } } }
64
65/*-*************************************
66*  Exceptions
67***************************************/
68#ifndef DEBUG
69#  define DEBUG 0
70#endif
71#define DEBUGOUTPUT(...) if (DEBUG) DISPLAY(__VA_ARGS__);
72#define EXM_THROW(error, ...)                                             \
73{                                                                         \
74    DEBUGOUTPUT("Error defined at %s, line %i : \n", __FILE__, __LINE__); \
75    DISPLAY("Error %i : ", error);                                        \
76    DISPLAY(__VA_ARGS__);                                                 \
77    DISPLAY("\n");                                                        \
78    exit(error);                                                          \
79}
80
81
82/* ********************************************************
83*  Helper functions
84**********************************************************/
85unsigned DiB_isError(size_t errorCode) { return ERR_isError(errorCode); }
86
87const char* DiB_getErrorName(size_t errorCode) { return ERR_getErrorName(errorCode); }
88
89#undef MIN
90#define MIN(a,b)    ((a) < (b) ? (a) : (b))
91
92
93/* ********************************************************
94*  File related operations
95**********************************************************/
96/** DiB_loadFiles() :
97 *  load samples from files listed in fileNamesTable into buffer.
98 *  works even if buffer is too small to load all samples.
99 *  Also provides the size of each sample into sampleSizes table
100 *  which must be sized correctly, using DiB_fileStats().
101 * @return : nb of samples effectively loaded into `buffer`
102 * *bufferSizePtr is modified, it provides the amount data loaded within buffer.
103 *  sampleSizes is filled with the size of each sample.
104 */
105static unsigned DiB_loadFiles(void* buffer, size_t* bufferSizePtr,
106                              size_t* sampleSizes, unsigned sstSize,
107                              const char** fileNamesTable, unsigned nbFiles, size_t targetChunkSize,
108                              unsigned displayLevel)
109{
110    char* const buff = (char*)buffer;
111    size_t pos = 0;
112    unsigned nbLoadedChunks = 0, fileIndex;
113
114    for (fileIndex=0; fileIndex<nbFiles; fileIndex++) {
115        const char* const fileName = fileNamesTable[fileIndex];
116        unsigned long long const fs64 = UTIL_getFileSize(fileName);
117        unsigned long long remainingToLoad = (fs64 == UTIL_FILESIZE_UNKNOWN) ? 0 : fs64;
118        U32 const nbChunks = targetChunkSize ? (U32)((fs64 + (targetChunkSize-1)) / targetChunkSize) : 1;
119        U64 const chunkSize = targetChunkSize ? MIN(targetChunkSize, fs64) : fs64;
120        size_t const maxChunkSize = (size_t)MIN(chunkSize, SAMPLESIZE_MAX);
121        U32 cnb;
122        FILE* const f = fopen(fileName, "rb");
123        if (f==NULL) EXM_THROW(10, "zstd: dictBuilder: %s %s ", fileName, strerror(errno));
124        DISPLAYUPDATE(2, "Loading %s...       \r", fileName);
125        for (cnb=0; cnb<nbChunks; cnb++) {
126            size_t const toLoad = (size_t)MIN(maxChunkSize, remainingToLoad);
127            if (toLoad > *bufferSizePtr-pos) break;
128            {   size_t const readSize = fread(buff+pos, 1, toLoad, f);
129                if (readSize != toLoad) EXM_THROW(11, "Pb reading %s", fileName);
130                pos += readSize;
131                sampleSizes[nbLoadedChunks++] = toLoad;
132                remainingToLoad -= targetChunkSize;
133                if (nbLoadedChunks == sstSize) { /* no more space left in sampleSizes table */
134                    fileIndex = nbFiles;  /* stop there */
135                    break;
136                }
137                if (toLoad < targetChunkSize) {
138                    fseek(f, (long)(targetChunkSize - toLoad), SEEK_CUR);
139        }   }   }
140        fclose(f);
141    }
142    DISPLAYLEVEL(2, "\r%79s\r", "");
143    *bufferSizePtr = pos;
144    DISPLAYLEVEL(4, "loaded : %u KB \n", (U32)(pos >> 10))
145    return nbLoadedChunks;
146}
147
148#define DiB_rotl32(x,r) ((x << r) | (x >> (32 - r)))
149static U32 DiB_rand(U32* src)
150{
151    static const U32 prime1 = 2654435761U;
152    static const U32 prime2 = 2246822519U;
153    U32 rand32 = *src;
154    rand32 *= prime1;
155    rand32 ^= prime2;
156    rand32  = DiB_rotl32(rand32, 13);
157    *src = rand32;
158    return rand32 >> 5;
159}
160
161/* DiB_shuffle() :
162 * shuffle a table of file names in a semi-random way
163 * It improves dictionary quality by reducing "locality" impact, so if sample set is very large,
164 * it will load random elements from it, instead of just the first ones. */
165static void DiB_shuffle(const char** fileNamesTable, unsigned nbFiles) {
166    U32 seed = 0xFD2FB528;
167    unsigned i;
168    for (i = nbFiles - 1; i > 0; --i) {
169        unsigned const j = DiB_rand(&seed) % (i + 1);
170        const char* const tmp = fileNamesTable[j];
171        fileNamesTable[j] = fileNamesTable[i];
172        fileNamesTable[i] = tmp;
173    }
174}
175
176
177/*-********************************************************
178*  Dictionary training functions
179**********************************************************/
180static size_t DiB_findMaxMem(unsigned long long requiredMem)
181{
182    size_t const step = 8 MB;
183    void* testmem = NULL;
184
185    requiredMem = (((requiredMem >> 23) + 1) << 23);
186    requiredMem += step;
187    if (requiredMem > g_maxMemory) requiredMem = g_maxMemory;
188
189    while (!testmem) {
190        testmem = malloc((size_t)requiredMem);
191        requiredMem -= step;
192    }
193
194    free(testmem);
195    return (size_t)requiredMem;
196}
197
198
199static void DiB_fillNoise(void* buffer, size_t length)
200{
201    unsigned const prime1 = 2654435761U;
202    unsigned const prime2 = 2246822519U;
203    unsigned acc = prime1;
204    size_t p=0;;
205
206    for (p=0; p<length; p++) {
207        acc *= prime2;
208        ((unsigned char*)buffer)[p] = (unsigned char)(acc >> 21);
209    }
210}
211
212
213static void DiB_saveDict(const char* dictFileName,
214                         const void* buff, size_t buffSize)
215{
216    FILE* const f = fopen(dictFileName, "wb");
217    if (f==NULL) EXM_THROW(3, "cannot open %s ", dictFileName);
218
219    { size_t const n = fwrite(buff, 1, buffSize, f);
220      if (n!=buffSize) EXM_THROW(4, "%s : write error", dictFileName) }
221
222    { size_t const n = (size_t)fclose(f);
223      if (n!=0) EXM_THROW(5, "%s : flush error", dictFileName) }
224}
225
226
227typedef struct {
228    U64 totalSizeToLoad;
229    unsigned oneSampleTooLarge;
230    unsigned nbSamples;
231} fileStats;
232
233/*! DiB_fileStats() :
234 *  Given a list of files, and a chunkSize (0 == no chunk, whole files)
235 *  provides the amount of data to be loaded and the resulting nb of samples.
236 *  This is useful primarily for allocation purpose => sample buffer, and sample sizes table.
237 */
238static fileStats DiB_fileStats(const char** fileNamesTable, unsigned nbFiles, size_t chunkSize, unsigned displayLevel)
239{
240    fileStats fs;
241    unsigned n;
242    memset(&fs, 0, sizeof(fs));
243    for (n=0; n<nbFiles; n++) {
244        U64 const fileSize = UTIL_getFileSize(fileNamesTable[n]);
245        U64 const srcSize = (fileSize == UTIL_FILESIZE_UNKNOWN) ? 0 : fileSize;
246        U32 const nbSamples = (U32)(chunkSize ? (srcSize + (chunkSize-1)) / chunkSize : 1);
247        U64 const chunkToLoad = chunkSize ? MIN(chunkSize, srcSize) : srcSize;
248        size_t const cappedChunkSize = (size_t)MIN(chunkToLoad, SAMPLESIZE_MAX);
249        fs.totalSizeToLoad += cappedChunkSize * nbSamples;
250        fs.oneSampleTooLarge |= (chunkSize > 2*SAMPLESIZE_MAX);
251        fs.nbSamples += nbSamples;
252    }
253    DISPLAYLEVEL(4, "Preparing to load : %u KB \n", (U32)(fs.totalSizeToLoad >> 10));
254    return fs;
255}
256
257
258/*! ZDICT_trainFromBuffer_unsafe_legacy() :
259    Strictly Internal use only !!
260    Same as ZDICT_trainFromBuffer_legacy(), but does not control `samplesBuffer`.
261    `samplesBuffer` must be followed by noisy guard band to avoid out-of-buffer reads.
262    @return : size of dictionary stored into `dictBuffer` (<= `dictBufferCapacity`)
263              or an error code.
264*/
265size_t ZDICT_trainFromBuffer_unsafe_legacy(void* dictBuffer, size_t dictBufferCapacity,
266                                           const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
267                                           ZDICT_legacy_params_t parameters);
268
269
270int DiB_trainFromFiles(const char* dictFileName, unsigned maxDictSize,
271                       const char** fileNamesTable, unsigned nbFiles, size_t chunkSize,
272                       ZDICT_legacy_params_t *params, ZDICT_cover_params_t *coverParams,
273                       int optimizeCover)
274{
275    unsigned const displayLevel = params ? params->zParams.notificationLevel :
276                        coverParams ? coverParams->zParams.notificationLevel :
277                        0;   /* should never happen */
278    void* const dictBuffer = malloc(maxDictSize);
279    fileStats const fs = DiB_fileStats(fileNamesTable, nbFiles, chunkSize, displayLevel);
280    size_t* const sampleSizes = (size_t*)malloc(fs.nbSamples * sizeof(size_t));
281    size_t const memMult = params ? MEMMULT : COVER_MEMMULT;
282    size_t const maxMem =  DiB_findMaxMem(fs.totalSizeToLoad * memMult) / memMult;
283    size_t loadedSize = (size_t) MIN ((unsigned long long)maxMem, fs.totalSizeToLoad);
284    void* const srcBuffer = malloc(loadedSize+NOISELENGTH);
285    int result = 0;
286
287    /* Checks */
288    if ((!sampleSizes) || (!srcBuffer) || (!dictBuffer))
289        EXM_THROW(12, "not enough memory for DiB_trainFiles");   /* should not happen */
290    if (fs.oneSampleTooLarge) {
291        DISPLAYLEVEL(2, "!  Warning : some sample(s) are very large \n");
292        DISPLAYLEVEL(2, "!  Note that dictionary is only useful for small samples. \n");
293        DISPLAYLEVEL(2, "!  As a consequence, only the first %u bytes of each sample are loaded \n", SAMPLESIZE_MAX);
294    }
295    if (fs.nbSamples < 5) {
296        DISPLAYLEVEL(2, "!  Warning : nb of samples too low for proper processing ! \n");
297        DISPLAYLEVEL(2, "!  Please provide _one file per sample_. \n");
298        DISPLAYLEVEL(2, "!  Alternatively, split files into fixed-size blocks representative of samples, with -B# \n");
299        EXM_THROW(14, "nb of samples too low");   /* we now clearly forbid this case */
300    }
301    if (fs.totalSizeToLoad < (unsigned long long)(8 * maxDictSize)) {
302        DISPLAYLEVEL(2, "!  Warning : data size of samples too small for target dictionary size \n");
303        DISPLAYLEVEL(2, "!  Samples should be about 100x larger than target dictionary size \n");
304    }
305
306    /* init */
307    if (loadedSize < fs.totalSizeToLoad)
308        DISPLAYLEVEL(1, "Not enough memory; training on %u MB only...\n", (unsigned)(loadedSize >> 20));
309
310    /* Load input buffer */
311    DISPLAYLEVEL(3, "Shuffling input files\n");
312    DiB_shuffle(fileNamesTable, nbFiles);
313    nbFiles = DiB_loadFiles(srcBuffer, &loadedSize, sampleSizes, fs.nbSamples, fileNamesTable, nbFiles, chunkSize, displayLevel);
314
315    {   size_t dictSize;
316        if (params) {
317            DiB_fillNoise((char*)srcBuffer + loadedSize, NOISELENGTH);   /* guard band, for end of buffer condition */
318            dictSize = ZDICT_trainFromBuffer_unsafe_legacy(dictBuffer, maxDictSize,
319                                                           srcBuffer, sampleSizes, fs.nbSamples,
320                                                           *params);
321        } else if (optimizeCover) {
322            dictSize = ZDICT_optimizeTrainFromBuffer_cover(dictBuffer, maxDictSize,
323                                                           srcBuffer, sampleSizes, fs.nbSamples,
324                                                           coverParams);
325            if (!ZDICT_isError(dictSize)) {
326                DISPLAYLEVEL(2, "k=%u\nd=%u\nsteps=%u\n", coverParams->k, coverParams->d, coverParams->steps);
327            }
328        } else {
329            dictSize = ZDICT_trainFromBuffer_cover(dictBuffer, maxDictSize, srcBuffer,
330                                                   sampleSizes, fs.nbSamples, *coverParams);
331        }
332        if (ZDICT_isError(dictSize)) {
333            DISPLAYLEVEL(1, "dictionary training failed : %s \n", ZDICT_getErrorName(dictSize));   /* should not happen */
334            result = 1;
335            goto _cleanup;
336        }
337        /* save dict */
338        DISPLAYLEVEL(2, "Save dictionary of size %u into file %s \n", (U32)dictSize, dictFileName);
339        DiB_saveDict(dictFileName, dictBuffer, dictSize);
340    }
341
342    /* clean up */
343_cleanup:
344    free(srcBuffer);
345    free(sampleSizes);
346    free(dictBuffer);
347    return result;
348}
349