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changed dictionary from using fixed amount of bytes for the header / entropy tables

dev
Paul Cruz 2017-06-14 17:23:56 -07:00
parent 664ed05ff6
commit d93207a79f
1 changed files with 14 additions and 9 deletions
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23
tests/decodecorpus.c
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@ -1316,25 +1316,30 @@ static int generateCorpusWithDict(U32 seed, unsigned numFiles, const char* const
const char* const origPath, const size_t dictSize)
{
char outPath[MAX_PATH];
BYTE* dictContent;
BYTE* fullDict;
U32 dictID;
unsigned fnum;
BYTE* decompressedPtr;
BYTE* dictContent;
const size_t headerSize = dictSize/4;
const size_t dictContentSize = dictSize - dictSize/4;
ZSTD_DCtx* dctx = ZSTD_createDCtx();
if(snprintf(outPath, MAX_PATH, "%s/dictionary", path) + 1 > MAX_PATH) {
DISPLAY("Error: path too long\n");
return 1;
}
if(dictSize < 400){
DISPLAY("Error: either no size given or given dictionary size is too small\n");
return 1;
{
/* use 3/4 of dictionary for content, save rest for header/entropy tables */
if(dictContentSize < 128 || dictSize < 256){
DISPLAY("Error: dictionary size is too small\n");
return 1;
}
}
/* Generate the dictionary randomly first */
dictContent = malloc(dictSize-400);
dictID = RAND(&seed);
fullDict = malloc(dictSize);
RAND_buffer(&seed, dictContent, dictSize-400);
dictContent = fullDict + headerSize;
RAND_buffer(&seed, (void*)dictContent, dictContentSize);
{
size_t dictWriteSize = 0;
@ -1347,7 +1352,7 @@ static int generateCorpusWithDict(U32 seed, unsigned numFiles, const char* const
size_t* curr = sampleSizes;
size_t totalSize = 0;
while(i++ < numSamples){
*curr = RAND(&seed) % (4 << 15);
*curr = RAND(&seed) % dictContentSize;
totalSize += *curr;
curr++;
}
@ -1360,7 +1365,7 @@ static int generateCorpusWithDict(U32 seed, unsigned numFiles, const char* const
{
/* take substring from dictionary content */
size_t pos = 0;
const BYTE* endDict = dictContent + dictSize - 400;
BYTE* endDict = dictContent + dictContentSize;
while(i++ < numSamples){
size_t currSize = *(curr++);
BYTE* startSubstring = endDict - currSize;
@ -1379,7 +1384,7 @@ static int generateCorpusWithDict(U32 seed, unsigned numFiles, const char* const
/* finalize dictionary with random samples */
dictWriteSize = ZDICT_finalizeDictionary(fullDict, dictSize,
dictContent, dictSize-400,
dictContent, dictContentSize,
samples, sampleSizes, numSamples,
zdictParams);
}