zstd/lib/compress/zstdmt_compress.c
Yann Collet 2bd6440be0 pinned down error code enum values
Note : all error codes are changed by this new version,
but it's expected to be the last change for existing codes.

Codes are now grouped by category, and receive a manually attributed value.
The objective is to guarantee that
error code values will not change in the future
when introducing new codes.
Intentionnal empty spaces and ranges are defined
in order to keep room for potential new codes.
2017-07-13 17:12:16 -07:00

1011 lines
42 KiB
C

/**
* Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/
/* ====== Tuning parameters ====== */
#define ZSTDMT_NBTHREADS_MAX 256
#define ZSTDMT_OVERLAPLOG_DEFAULT 6
/* ====== Compiler specifics ====== */
#if defined(_MSC_VER)
# pragma warning(disable : 4204) /* disable: C4204: non-constant aggregate initializer */
#endif
/* ====== Dependencies ====== */
#include <string.h> /* memcpy, memset */
#include "pool.h" /* threadpool */
#include "threading.h" /* mutex */
#include "zstd_internal.h" /* MIN, ERROR, ZSTD_*, ZSTD_highbit32 */
#include "zstdmt_compress.h"
/* ====== Debug ====== */
#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=2)
# include <stdio.h>
# include <unistd.h>
# include <sys/times.h>
# define DEBUGLOGRAW(l, ...) if (l<=ZSTD_DEBUG) { fprintf(stderr, __VA_ARGS__); }
# define DEBUG_PRINTHEX(l,p,n) { \
unsigned debug_u; \
for (debug_u=0; debug_u<(n); debug_u++) \
DEBUGLOGRAW(l, "%02X ", ((const unsigned char*)(p))[debug_u]); \
DEBUGLOGRAW(l, " \n"); \
}
static unsigned long long GetCurrentClockTimeMicroseconds(void)
{
static clock_t _ticksPerSecond = 0;
if (_ticksPerSecond <= 0) _ticksPerSecond = sysconf(_SC_CLK_TCK);
{ struct tms junk; clock_t newTicks = (clock_t) times(&junk);
return ((((unsigned long long)newTicks)*(1000000))/_ticksPerSecond); }
}
#define MUTEX_WAIT_TIME_DLEVEL 6
#define PTHREAD_MUTEX_LOCK(mutex) { \
if (ZSTD_DEBUG>=MUTEX_WAIT_TIME_DLEVEL) { \
unsigned long long const beforeTime = GetCurrentClockTimeMicroseconds(); \
pthread_mutex_lock(mutex); \
{ unsigned long long const afterTime = GetCurrentClockTimeMicroseconds(); \
unsigned long long const elapsedTime = (afterTime-beforeTime); \
if (elapsedTime > 1000) { /* or whatever threshold you like; I'm using 1 millisecond here */ \
DEBUGLOG(MUTEX_WAIT_TIME_DLEVEL, "Thread took %llu microseconds to acquire mutex %s \n", \
elapsedTime, #mutex); \
} } \
} else pthread_mutex_lock(mutex); \
}
#else
# define PTHREAD_MUTEX_LOCK(m) pthread_mutex_lock(m)
# define DEBUG_PRINTHEX(l,p,n) {}
#endif
/* ===== Buffer Pool ===== */
/* a single Buffer Pool can be invoked from multiple threads in parallel */
typedef struct buffer_s {
void* start;
size_t size;
} buffer_t;
static const buffer_t g_nullBuffer = { NULL, 0 };
typedef struct ZSTDMT_bufferPool_s {
pthread_mutex_t poolMutex;
size_t bufferSize;
unsigned totalBuffers;
unsigned nbBuffers;
ZSTD_customMem cMem;
buffer_t bTable[1]; /* variable size */
} ZSTDMT_bufferPool;
static ZSTDMT_bufferPool* ZSTDMT_createBufferPool(unsigned nbThreads, ZSTD_customMem cMem)
{
unsigned const maxNbBuffers = 2*nbThreads + 3;
ZSTDMT_bufferPool* const bufPool = (ZSTDMT_bufferPool*)ZSTD_calloc(
sizeof(ZSTDMT_bufferPool) + (maxNbBuffers-1) * sizeof(buffer_t), cMem);
if (bufPool==NULL) return NULL;
pthread_mutex_init(&bufPool->poolMutex, NULL);
bufPool->bufferSize = 64 KB;
bufPool->totalBuffers = maxNbBuffers;
bufPool->nbBuffers = 0;
bufPool->cMem = cMem;
return bufPool;
}
static void ZSTDMT_freeBufferPool(ZSTDMT_bufferPool* bufPool)
{
unsigned u;
if (!bufPool) return; /* compatibility with free on NULL */
for (u=0; u<bufPool->totalBuffers; u++)
ZSTD_free(bufPool->bTable[u].start, bufPool->cMem);
pthread_mutex_destroy(&bufPool->poolMutex);
ZSTD_free(bufPool, bufPool->cMem);
}
/* only works at initialization, not during compression */
static size_t ZSTDMT_sizeof_bufferPool(ZSTDMT_bufferPool* bufPool)
{
size_t const poolSize = sizeof(*bufPool)
+ (bufPool->totalBuffers - 1) * sizeof(buffer_t);
unsigned u;
size_t totalBufferSize = 0;
pthread_mutex_lock(&bufPool->poolMutex);
for (u=0; u<bufPool->totalBuffers; u++)
totalBufferSize += bufPool->bTable[u].size;
pthread_mutex_unlock(&bufPool->poolMutex);
return poolSize + totalBufferSize;
}
static void ZSTDMT_setBufferSize(ZSTDMT_bufferPool* bufPool, size_t bSize)
{
bufPool->bufferSize = bSize;
}
/** ZSTDMT_getBuffer() :
* assumption : bufPool must be valid */
static buffer_t ZSTDMT_getBuffer(ZSTDMT_bufferPool* bufPool)
{
size_t const bSize = bufPool->bufferSize;
DEBUGLOG(5, "ZSTDMT_getBuffer");
pthread_mutex_lock(&bufPool->poolMutex);
if (bufPool->nbBuffers) { /* try to use an existing buffer */
buffer_t const buf = bufPool->bTable[--(bufPool->nbBuffers)];
size_t const availBufferSize = buf.size;
if ((availBufferSize >= bSize) & (availBufferSize <= 10*bSize)) {
/* large enough, but not too much */
pthread_mutex_unlock(&bufPool->poolMutex);
return buf;
}
/* size conditions not respected : scratch this buffer, create new one */
DEBUGLOG(5, "existing buffer does not meet size conditions => freeing");
ZSTD_free(buf.start, bufPool->cMem);
}
pthread_mutex_unlock(&bufPool->poolMutex);
/* create new buffer */
DEBUGLOG(5, "create a new buffer");
{ buffer_t buffer;
void* const start = ZSTD_malloc(bSize, bufPool->cMem);
buffer.start = start; /* note : start can be NULL if malloc fails ! */
buffer.size = (start==NULL) ? 0 : bSize;
return buffer;
}
}
/* store buffer for later re-use, up to pool capacity */
static void ZSTDMT_releaseBuffer(ZSTDMT_bufferPool* bufPool, buffer_t buf)
{
if (buf.start == NULL) return; /* compatible with release on NULL */
DEBUGLOG(5, "ZSTDMT_releaseBuffer");
pthread_mutex_lock(&bufPool->poolMutex);
if (bufPool->nbBuffers < bufPool->totalBuffers) {
bufPool->bTable[bufPool->nbBuffers++] = buf; /* stored for later use */
pthread_mutex_unlock(&bufPool->poolMutex);
return;
}
pthread_mutex_unlock(&bufPool->poolMutex);
/* Reached bufferPool capacity (should not happen) */
DEBUGLOG(5, "buffer pool capacity reached => freeing ");
ZSTD_free(buf.start, bufPool->cMem);
}
/* ===== CCtx Pool ===== */
/* a single CCtx Pool can be invoked from multiple threads in parallel */
typedef struct {
pthread_mutex_t poolMutex;
unsigned totalCCtx;
unsigned availCCtx;
ZSTD_customMem cMem;
ZSTD_CCtx* cctx[1]; /* variable size */
} ZSTDMT_CCtxPool;
/* note : all CCtx borrowed from the pool should be released back to the pool _before_ freeing the pool */
static void ZSTDMT_freeCCtxPool(ZSTDMT_CCtxPool* pool)
{
unsigned u;
for (u=0; u<pool->totalCCtx; u++)
ZSTD_freeCCtx(pool->cctx[u]); /* note : compatible with free on NULL */
pthread_mutex_destroy(&pool->poolMutex);
ZSTD_free(pool, pool->cMem);
}
/* ZSTDMT_createCCtxPool() :
* implies nbThreads >= 1 , checked by caller ZSTDMT_createCCtx() */
static ZSTDMT_CCtxPool* ZSTDMT_createCCtxPool(unsigned nbThreads,
ZSTD_customMem cMem)
{
ZSTDMT_CCtxPool* const cctxPool = (ZSTDMT_CCtxPool*) ZSTD_calloc(
sizeof(ZSTDMT_CCtxPool) + (nbThreads-1)*sizeof(ZSTD_CCtx*), cMem);
if (!cctxPool) return NULL;
pthread_mutex_init(&cctxPool->poolMutex, NULL);
cctxPool->cMem = cMem;
cctxPool->totalCCtx = nbThreads;
cctxPool->availCCtx = 1; /* at least one cctx for single-thread mode */
cctxPool->cctx[0] = ZSTD_createCCtx_advanced(cMem);
if (!cctxPool->cctx[0]) { ZSTDMT_freeCCtxPool(cctxPool); return NULL; }
DEBUGLOG(3, "cctxPool created, with %u threads", nbThreads);
return cctxPool;
}
/* only works during initialization phase, not during compression */
static size_t ZSTDMT_sizeof_CCtxPool(ZSTDMT_CCtxPool* cctxPool)
{
pthread_mutex_lock(&cctxPool->poolMutex);
{ unsigned const nbThreads = cctxPool->totalCCtx;
size_t const poolSize = sizeof(*cctxPool)
+ (nbThreads-1)*sizeof(ZSTD_CCtx*);
unsigned u;
size_t totalCCtxSize = 0;
for (u=0; u<nbThreads; u++) {
totalCCtxSize += ZSTD_sizeof_CCtx(cctxPool->cctx[u]);
}
pthread_mutex_unlock(&cctxPool->poolMutex);
return poolSize + totalCCtxSize;
}
}
static ZSTD_CCtx* ZSTDMT_getCCtx(ZSTDMT_CCtxPool* cctxPool)
{
DEBUGLOG(5, "ZSTDMT_getCCtx");
pthread_mutex_lock(&cctxPool->poolMutex);
if (cctxPool->availCCtx) {
cctxPool->availCCtx--;
{ ZSTD_CCtx* const cctx = cctxPool->cctx[cctxPool->availCCtx];
pthread_mutex_unlock(&cctxPool->poolMutex);
return cctx;
} }
pthread_mutex_unlock(&cctxPool->poolMutex);
DEBUGLOG(5, "create one more CCtx");
return ZSTD_createCCtx_advanced(cctxPool->cMem); /* note : can be NULL, when creation fails ! */
}
static void ZSTDMT_releaseCCtx(ZSTDMT_CCtxPool* pool, ZSTD_CCtx* cctx)
{
if (cctx==NULL) return; /* compatibility with release on NULL */
pthread_mutex_lock(&pool->poolMutex);
if (pool->availCCtx < pool->totalCCtx)
pool->cctx[pool->availCCtx++] = cctx;
else {
/* pool overflow : should not happen, since totalCCtx==nbThreads */
DEBUGLOG(5, "CCtx pool overflow : free cctx");
ZSTD_freeCCtx(cctx);
}
pthread_mutex_unlock(&pool->poolMutex);
}
/* ===== Thread worker ===== */
typedef struct {
buffer_t src;
const void* srcStart;
size_t dictSize;
size_t srcSize;
buffer_t dstBuff;
size_t cSize;
size_t dstFlushed;
unsigned firstChunk;
unsigned lastChunk;
unsigned jobCompleted;
unsigned jobScanned;
pthread_mutex_t* jobCompleted_mutex;
pthread_cond_t* jobCompleted_cond;
ZSTD_parameters params;
const ZSTD_CDict* cdict;
ZSTDMT_CCtxPool* cctxPool;
ZSTDMT_bufferPool* bufPool;
unsigned long long fullFrameSize;
} ZSTDMT_jobDescription;
/* ZSTDMT_compressChunk() : POOL_function type */
void ZSTDMT_compressChunk(void* jobDescription)
{
ZSTDMT_jobDescription* const job = (ZSTDMT_jobDescription*)jobDescription;
ZSTD_CCtx* cctx = ZSTDMT_getCCtx(job->cctxPool);
const void* const src = (const char*)job->srcStart + job->dictSize;
buffer_t dstBuff = job->dstBuff;
DEBUGLOG(5, "job (first:%u) (last:%u) : dictSize %u, srcSize %u",
job->firstChunk, job->lastChunk, (U32)job->dictSize, (U32)job->srcSize);
if (cctx==NULL) {
job->cSize = ERROR(memory_allocation);
goto _endJob;
}
if (dstBuff.start == NULL) {
dstBuff = ZSTDMT_getBuffer(job->bufPool);
if (dstBuff.start==NULL) {
job->cSize = ERROR(memory_allocation);
goto _endJob;
}
job->dstBuff = dstBuff;
}
if (job->cdict) { /* should only happen for first segment */
size_t const initError = ZSTD_compressBegin_usingCDict_advanced(cctx, job->cdict, job->params.fParams, job->fullFrameSize);
DEBUGLOG(5, "using CDict");
if (ZSTD_isError(initError)) { job->cSize = initError; goto _endJob; }
} else { /* srcStart points at reloaded section */
if (!job->firstChunk) job->params.fParams.contentSizeFlag = 0; /* ensure no srcSize control */
{ size_t const dictModeError = ZSTD_setCCtxParameter(cctx, ZSTD_p_forceRawDict, 1); /* Force loading dictionary in "content-only" mode (no header analysis) */
size_t const initError = ZSTD_compressBegin_advanced(cctx, job->srcStart, job->dictSize, job->params, job->fullFrameSize);
if (ZSTD_isError(initError) || ZSTD_isError(dictModeError)) { job->cSize = initError; goto _endJob; }
ZSTD_setCCtxParameter(cctx, ZSTD_p_forceWindow, 1);
} }
if (!job->firstChunk) { /* flush and overwrite frame header when it's not first segment */
size_t const hSize = ZSTD_compressContinue(cctx, dstBuff.start, dstBuff.size, src, 0);
if (ZSTD_isError(hSize)) { job->cSize = hSize; goto _endJob; }
ZSTD_invalidateRepCodes(cctx);
}
DEBUGLOG(5, "Compressing : ");
DEBUG_PRINTHEX(4, job->srcStart, 12);
job->cSize = (job->lastChunk) ?
ZSTD_compressEnd (cctx, dstBuff.start, dstBuff.size, src, job->srcSize) :
ZSTD_compressContinue(cctx, dstBuff.start, dstBuff.size, src, job->srcSize);
DEBUGLOG(5, "compressed %u bytes into %u bytes (first:%u) (last:%u)",
(unsigned)job->srcSize, (unsigned)job->cSize, job->firstChunk, job->lastChunk);
DEBUGLOG(5, "dstBuff.size : %u ; => %s", (U32)dstBuff.size, ZSTD_getErrorName(job->cSize));
_endJob:
ZSTDMT_releaseCCtx(job->cctxPool, cctx);
ZSTDMT_releaseBuffer(job->bufPool, job->src);
job->src = g_nullBuffer; job->srcStart = NULL;
PTHREAD_MUTEX_LOCK(job->jobCompleted_mutex);
job->jobCompleted = 1;
job->jobScanned = 0;
pthread_cond_signal(job->jobCompleted_cond);
pthread_mutex_unlock(job->jobCompleted_mutex);
}
/* ------------------------------------------ */
/* ===== Multi-threaded compression ===== */
/* ------------------------------------------ */
typedef struct {
buffer_t buffer;
size_t filled;
} inBuff_t;
struct ZSTDMT_CCtx_s {
POOL_ctx* factory;
ZSTDMT_jobDescription* jobs;
ZSTDMT_bufferPool* bufPool;
ZSTDMT_CCtxPool* cctxPool;
pthread_mutex_t jobCompleted_mutex;
pthread_cond_t jobCompleted_cond;
size_t targetSectionSize;
size_t inBuffSize;
size_t dictSize;
size_t targetDictSize;
inBuff_t inBuff;
ZSTD_parameters params;
XXH64_state_t xxhState;
unsigned nbThreads;
unsigned jobIDMask;
unsigned doneJobID;
unsigned nextJobID;
unsigned frameEnded;
unsigned allJobsCompleted;
unsigned overlapLog;
unsigned long long frameContentSize;
size_t sectionSize;
ZSTD_customMem cMem;
ZSTD_CDict* cdictLocal;
const ZSTD_CDict* cdict;
};
static ZSTDMT_jobDescription* ZSTDMT_allocJobsTable(U32* nbJobsPtr, ZSTD_customMem cMem)
{
U32 const nbJobsLog2 = ZSTD_highbit32(*nbJobsPtr) + 1;
U32 const nbJobs = 1 << nbJobsLog2;
*nbJobsPtr = nbJobs;
return (ZSTDMT_jobDescription*) ZSTD_calloc(
nbJobs * sizeof(ZSTDMT_jobDescription), cMem);
}
ZSTDMT_CCtx* ZSTDMT_createCCtx_advanced(unsigned nbThreads, ZSTD_customMem cMem)
{
ZSTDMT_CCtx* mtctx;
U32 nbJobs = nbThreads + 2;
DEBUGLOG(3, "ZSTDMT_createCCtx_advanced");
if (nbThreads < 1) return NULL;
nbThreads = MIN(nbThreads , ZSTDMT_NBTHREADS_MAX);
if ((cMem.customAlloc!=NULL) ^ (cMem.customFree!=NULL))
/* invalid custom allocator */
return NULL;
mtctx = (ZSTDMT_CCtx*) ZSTD_calloc(sizeof(ZSTDMT_CCtx), cMem);
if (!mtctx) return NULL;
mtctx->cMem = cMem;
mtctx->nbThreads = nbThreads;
mtctx->allJobsCompleted = 1;
mtctx->sectionSize = 0;
mtctx->overlapLog = ZSTDMT_OVERLAPLOG_DEFAULT;
mtctx->factory = POOL_create(nbThreads, 1);
mtctx->jobs = ZSTDMT_allocJobsTable(&nbJobs, cMem);
mtctx->jobIDMask = nbJobs - 1;
mtctx->bufPool = ZSTDMT_createBufferPool(nbThreads, cMem);
mtctx->cctxPool = ZSTDMT_createCCtxPool(nbThreads, cMem);
if (!mtctx->factory | !mtctx->jobs | !mtctx->bufPool | !mtctx->cctxPool) {
ZSTDMT_freeCCtx(mtctx);
return NULL;
}
pthread_mutex_init(&mtctx->jobCompleted_mutex, NULL); /* Todo : check init function return */
pthread_cond_init(&mtctx->jobCompleted_cond, NULL);
DEBUGLOG(3, "mt_cctx created, for %u threads", nbThreads);
return mtctx;
}
ZSTDMT_CCtx* ZSTDMT_createCCtx(unsigned nbThreads)
{
return ZSTDMT_createCCtx_advanced(nbThreads, ZSTD_defaultCMem);
}
/* ZSTDMT_releaseAllJobResources() :
* note : ensure all workers are killed first ! */
static void ZSTDMT_releaseAllJobResources(ZSTDMT_CCtx* mtctx)
{
unsigned jobID;
DEBUGLOG(3, "ZSTDMT_releaseAllJobResources");
for (jobID=0; jobID <= mtctx->jobIDMask; jobID++) {
ZSTDMT_releaseBuffer(mtctx->bufPool, mtctx->jobs[jobID].dstBuff);
mtctx->jobs[jobID].dstBuff = g_nullBuffer;
ZSTDMT_releaseBuffer(mtctx->bufPool, mtctx->jobs[jobID].src);
mtctx->jobs[jobID].src = g_nullBuffer;
}
memset(mtctx->jobs, 0, (mtctx->jobIDMask+1)*sizeof(ZSTDMT_jobDescription));
ZSTDMT_releaseBuffer(mtctx->bufPool, mtctx->inBuff.buffer);
mtctx->inBuff.buffer = g_nullBuffer;
mtctx->allJobsCompleted = 1;
}
size_t ZSTDMT_freeCCtx(ZSTDMT_CCtx* mtctx)
{
if (mtctx==NULL) return 0; /* compatible with free on NULL */
POOL_free(mtctx->factory);
if (!mtctx->allJobsCompleted) ZSTDMT_releaseAllJobResources(mtctx); /* stop workers first */
ZSTDMT_freeBufferPool(mtctx->bufPool); /* release job resources into pools first */
ZSTD_free(mtctx->jobs, mtctx->cMem);
ZSTDMT_freeCCtxPool(mtctx->cctxPool);
ZSTD_freeCDict(mtctx->cdictLocal);
pthread_mutex_destroy(&mtctx->jobCompleted_mutex);
pthread_cond_destroy(&mtctx->jobCompleted_cond);
ZSTD_free(mtctx, mtctx->cMem);
return 0;
}
size_t ZSTDMT_sizeof_CCtx(ZSTDMT_CCtx* mtctx)
{
if (mtctx == NULL) return 0; /* supports sizeof NULL */
return sizeof(*mtctx)
+ POOL_sizeof(mtctx->factory)
+ ZSTDMT_sizeof_bufferPool(mtctx->bufPool)
+ (mtctx->jobIDMask+1) * sizeof(ZSTDMT_jobDescription)
+ ZSTDMT_sizeof_CCtxPool(mtctx->cctxPool)
+ ZSTD_sizeof_CDict(mtctx->cdictLocal);
}
size_t ZSTDMT_setMTCtxParameter(ZSTDMT_CCtx* mtctx, ZSDTMT_parameter parameter, unsigned value)
{
switch(parameter)
{
case ZSTDMT_p_sectionSize :
mtctx->sectionSize = value;
return 0;
case ZSTDMT_p_overlapSectionLog :
DEBUGLOG(5, "ZSTDMT_p_overlapSectionLog : %u", value);
mtctx->overlapLog = (value >= 9) ? 9 : value;
return 0;
default :
return ERROR(parameter_unsupported);
}
}
/* ------------------------------------------ */
/* ===== Multi-threaded compression ===== */
/* ------------------------------------------ */
static unsigned computeNbChunks(size_t srcSize, unsigned windowLog, unsigned nbThreads) {
size_t const chunkSizeTarget = (size_t)1 << (windowLog + 2);
size_t const chunkMaxSize = chunkSizeTarget << 2;
size_t const passSizeMax = chunkMaxSize * nbThreads;
unsigned const multiplier = (unsigned)(srcSize / passSizeMax) + 1;
unsigned const nbChunksLarge = multiplier * nbThreads;
unsigned const nbChunksMax = (unsigned)(srcSize / chunkSizeTarget) + 1;
unsigned const nbChunksSmall = MIN(nbChunksMax, nbThreads);
return (multiplier>1) ? nbChunksLarge : nbChunksSmall;
}
size_t ZSTDMT_compress_advanced(ZSTDMT_CCtx* mtctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
const ZSTD_CDict* cdict,
ZSTD_parameters const params,
unsigned overlapLog)
{
unsigned const overlapRLog = (overlapLog>9) ? 0 : 9-overlapLog;
size_t const overlapSize = (overlapRLog>=9) ? 0 : (size_t)1 << (params.cParams.windowLog - overlapRLog);
unsigned nbChunks = computeNbChunks(srcSize, params.cParams.windowLog, mtctx->nbThreads);
size_t const proposedChunkSize = (srcSize + (nbChunks-1)) / nbChunks;
size_t const avgChunkSize = ((proposedChunkSize & 0x1FFFF) < 0x7FFF) ? proposedChunkSize + 0xFFFF : proposedChunkSize; /* avoid too small last block */
const char* const srcStart = (const char*)src;
size_t remainingSrcSize = srcSize;
unsigned const compressWithinDst = (dstCapacity >= ZSTD_compressBound(srcSize)) ? nbChunks : (unsigned)(dstCapacity / ZSTD_compressBound(avgChunkSize)); /* presumes avgChunkSize >= 256 KB, which should be the case */
size_t frameStartPos = 0, dstBufferPos = 0;
XXH64_state_t xxh64;
DEBUGLOG(4, "nbChunks : %2u (chunkSize : %u bytes) ", nbChunks, (U32)avgChunkSize);
if (nbChunks==1) { /* fallback to single-thread mode */
ZSTD_CCtx* const cctx = mtctx->cctxPool->cctx[0];
if (cdict) return ZSTD_compress_usingCDict_advanced(cctx, dst, dstCapacity, src, srcSize, cdict, params.fParams);
return ZSTD_compress_advanced(cctx, dst, dstCapacity, src, srcSize, NULL, 0, params);
}
assert(avgChunkSize >= 256 KB); /* condition for ZSTD_compressBound(A) + ZSTD_compressBound(B) <= ZSTD_compressBound(A+B), which is required for compressWithinDst */
ZSTDMT_setBufferSize(mtctx->bufPool, ZSTD_compressBound(avgChunkSize) );
XXH64_reset(&xxh64, 0);
if (nbChunks > mtctx->jobIDMask+1) { /* enlarge job table */
U32 nbJobs = nbChunks;
ZSTD_free(mtctx->jobs, mtctx->cMem);
mtctx->jobIDMask = 0;
mtctx->jobs = ZSTDMT_allocJobsTable(&nbJobs, mtctx->cMem);
if (mtctx->jobs==NULL) return ERROR(memory_allocation);
mtctx->jobIDMask = nbJobs - 1;
}
{ unsigned u;
for (u=0; u<nbChunks; u++) {
size_t const chunkSize = MIN(remainingSrcSize, avgChunkSize);
size_t const dstBufferCapacity = ZSTD_compressBound(chunkSize);
buffer_t const dstAsBuffer = { (char*)dst + dstBufferPos, dstBufferCapacity };
buffer_t const dstBuffer = u < compressWithinDst ? dstAsBuffer : g_nullBuffer;
size_t dictSize = u ? overlapSize : 0;
mtctx->jobs[u].src = g_nullBuffer;
mtctx->jobs[u].srcStart = srcStart + frameStartPos - dictSize;
mtctx->jobs[u].dictSize = dictSize;
mtctx->jobs[u].srcSize = chunkSize;
mtctx->jobs[u].cdict = mtctx->nextJobID==0 ? cdict : NULL;
mtctx->jobs[u].fullFrameSize = srcSize;
mtctx->jobs[u].params = params;
/* do not calculate checksum within sections, but write it in header for first section */
if (u!=0) mtctx->jobs[u].params.fParams.checksumFlag = 0;
mtctx->jobs[u].dstBuff = dstBuffer;
mtctx->jobs[u].cctxPool = mtctx->cctxPool;
mtctx->jobs[u].bufPool = mtctx->bufPool;
mtctx->jobs[u].firstChunk = (u==0);
mtctx->jobs[u].lastChunk = (u==nbChunks-1);
mtctx->jobs[u].jobCompleted = 0;
mtctx->jobs[u].jobCompleted_mutex = &mtctx->jobCompleted_mutex;
mtctx->jobs[u].jobCompleted_cond = &mtctx->jobCompleted_cond;
if (params.fParams.checksumFlag) {
XXH64_update(&xxh64, srcStart + frameStartPos, chunkSize);
}
DEBUGLOG(5, "posting job %u (%u bytes)", u, (U32)chunkSize);
DEBUG_PRINTHEX(6, mtctx->jobs[u].srcStart, 12);
POOL_add(mtctx->factory, ZSTDMT_compressChunk, &mtctx->jobs[u]);
frameStartPos += chunkSize;
dstBufferPos += dstBufferCapacity;
remainingSrcSize -= chunkSize;
} }
/* collect result */
{ size_t error = 0, dstPos = 0;
unsigned chunkID;
for (chunkID=0; chunkID<nbChunks; chunkID++) {
DEBUGLOG(5, "waiting for chunk %u ", chunkID);
PTHREAD_MUTEX_LOCK(&mtctx->jobCompleted_mutex);
while (mtctx->jobs[chunkID].jobCompleted==0) {
DEBUGLOG(5, "waiting for jobCompleted signal from chunk %u", chunkID);
pthread_cond_wait(&mtctx->jobCompleted_cond, &mtctx->jobCompleted_mutex);
}
pthread_mutex_unlock(&mtctx->jobCompleted_mutex);
DEBUGLOG(5, "ready to write chunk %u ", chunkID);
mtctx->jobs[chunkID].srcStart = NULL;
{ size_t const cSize = mtctx->jobs[chunkID].cSize;
if (ZSTD_isError(cSize)) error = cSize;
if ((!error) && (dstPos + cSize > dstCapacity)) error = ERROR(dstSize_tooSmall);
if (chunkID) { /* note : chunk 0 is written directly at dst, which is correct position */
if (!error)
memmove((char*)dst + dstPos, mtctx->jobs[chunkID].dstBuff.start, cSize); /* may overlap when chunk compressed within dst */
if (chunkID >= compressWithinDst) { /* chunk compressed into its own buffer, which must be released */
DEBUGLOG(5, "releasing buffer %u>=%u", chunkID, compressWithinDst);
ZSTDMT_releaseBuffer(mtctx->bufPool, mtctx->jobs[chunkID].dstBuff);
}
mtctx->jobs[chunkID].dstBuff = g_nullBuffer;
}
dstPos += cSize ;
}
} /* for (chunkID=0; chunkID<nbChunks; chunkID++) */
DEBUGLOG(4, "checksumFlag : %u ", params.fParams.checksumFlag);
if (params.fParams.checksumFlag) {
U32 const checksum = (U32)XXH64_digest(&xxh64);
if (dstPos + 4 > dstCapacity) {
error = ERROR(dstSize_tooSmall);
} else {
DEBUGLOG(4, "writing checksum : %08X \n", checksum);
MEM_writeLE32((char*)dst + dstPos, checksum);
dstPos += 4;
} }
if (!error) DEBUGLOG(4, "compressed size : %u ", (U32)dstPos);
return error ? error : dstPos;
}
}
size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
int compressionLevel)
{
U32 const overlapLog = (compressionLevel >= ZSTD_maxCLevel()) ? 9 : ZSTDMT_OVERLAPLOG_DEFAULT;
ZSTD_parameters params = ZSTD_getParams(compressionLevel, srcSize, 0);
params.fParams.contentSizeFlag = 1;
return ZSTDMT_compress_advanced(mtctx, dst, dstCapacity, src, srcSize, NULL, params, overlapLog);
}
/* ====================================== */
/* ======= Streaming API ======= */
/* ====================================== */
static void ZSTDMT_waitForAllJobsCompleted(ZSTDMT_CCtx* zcs)
{
DEBUGLOG(4, "ZSTDMT_waitForAllJobsCompleted");
while (zcs->doneJobID < zcs->nextJobID) {
unsigned const jobID = zcs->doneJobID & zcs->jobIDMask;
PTHREAD_MUTEX_LOCK(&zcs->jobCompleted_mutex);
while (zcs->jobs[jobID].jobCompleted==0) {
DEBUGLOG(5, "waiting for jobCompleted signal from chunk %u", zcs->doneJobID); /* we want to block when waiting for data to flush */
pthread_cond_wait(&zcs->jobCompleted_cond, &zcs->jobCompleted_mutex);
}
pthread_mutex_unlock(&zcs->jobCompleted_mutex);
zcs->doneJobID++;
}
}
/** ZSTDMT_initCStream_internal() :
* internal usage only */
size_t ZSTDMT_initCStream_internal(ZSTDMT_CCtx* zcs,
const void* dict, size_t dictSize, const ZSTD_CDict* cdict,
ZSTD_parameters params, unsigned long long pledgedSrcSize)
{
DEBUGLOG(4, "ZSTDMT_initCStream_internal");
/* params are supposed to be fully validated at this point */
assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
assert(!((dict) && (cdict))); /* either dict or cdict, not both */
if (zcs->nbThreads==1) {
DEBUGLOG(4, "single thread mode");
return ZSTD_initCStream_internal(zcs->cctxPool->cctx[0],
dict, dictSize, cdict,
params, pledgedSrcSize);
}
if (zcs->allJobsCompleted == 0) { /* previous compression not correctly finished */
ZSTDMT_waitForAllJobsCompleted(zcs);
ZSTDMT_releaseAllJobResources(zcs);
zcs->allJobsCompleted = 1;
}
zcs->params = params;
zcs->frameContentSize = pledgedSrcSize;
if (dict) {
DEBUGLOG(4,"cdictLocal: %08X", (U32)(size_t)zcs->cdictLocal);
ZSTD_freeCDict(zcs->cdictLocal);
zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize,
0 /* byRef */, ZSTD_dm_auto, /* note : a loadPrefix becomes an internal CDict */
params.cParams, zcs->cMem);
zcs->cdict = zcs->cdictLocal;
if (zcs->cdictLocal == NULL) return ERROR(memory_allocation);
} else {
DEBUGLOG(4,"cdictLocal: %08X", (U32)(size_t)zcs->cdictLocal);
ZSTD_freeCDict(zcs->cdictLocal);
zcs->cdictLocal = NULL;
zcs->cdict = cdict;
}
zcs->targetDictSize = (zcs->overlapLog==0) ? 0 : (size_t)1 << (zcs->params.cParams.windowLog - (9 - zcs->overlapLog));
DEBUGLOG(4, "overlapLog : %u ", zcs->overlapLog);
DEBUGLOG(4, "overlap Size : %u KB", (U32)(zcs->targetDictSize>>10));
zcs->targetSectionSize = zcs->sectionSize ? zcs->sectionSize : (size_t)1 << (zcs->params.cParams.windowLog + 2);
zcs->targetSectionSize = MAX(ZSTDMT_SECTION_SIZE_MIN, zcs->targetSectionSize);
zcs->targetSectionSize = MAX(zcs->targetDictSize, zcs->targetSectionSize);
DEBUGLOG(4, "Section Size : %u KB", (U32)(zcs->targetSectionSize>>10));
zcs->inBuffSize = zcs->targetDictSize + zcs->targetSectionSize;
ZSTDMT_setBufferSize(zcs->bufPool, MAX(zcs->inBuffSize, ZSTD_compressBound(zcs->targetSectionSize)) );
zcs->inBuff.buffer = g_nullBuffer;
zcs->dictSize = 0;
zcs->doneJobID = 0;
zcs->nextJobID = 0;
zcs->frameEnded = 0;
zcs->allJobsCompleted = 0;
if (params.fParams.checksumFlag) XXH64_reset(&zcs->xxhState, 0);
return 0;
}
size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* mtctx,
const void* dict, size_t dictSize,
ZSTD_parameters params,
unsigned long long pledgedSrcSize)
{
DEBUGLOG(5, "ZSTDMT_initCStream_advanced");
return ZSTDMT_initCStream_internal(mtctx, dict, dictSize, NULL, params, pledgedSrcSize);
}
size_t ZSTDMT_initCStream_usingCDict(ZSTDMT_CCtx* mtctx,
const ZSTD_CDict* cdict,
ZSTD_frameParameters fParams,
unsigned long long pledgedSrcSize)
{
ZSTD_parameters params = ZSTD_getParamsFromCDict(cdict);
if (cdict==NULL) return ERROR(dictionary_wrong); /* method incompatible with NULL cdict */
params.fParams = fParams;
return ZSTDMT_initCStream_internal(mtctx, NULL, 0 /*dictSize*/, cdict,
params, pledgedSrcSize);
}
/* ZSTDMT_resetCStream() :
* pledgedSrcSize is optional and can be zero == unknown */
size_t ZSTDMT_resetCStream(ZSTDMT_CCtx* zcs, unsigned long long pledgedSrcSize)
{
if (zcs->nbThreads==1)
return ZSTD_resetCStream(zcs->cctxPool->cctx[0], pledgedSrcSize);
return ZSTDMT_initCStream_internal(zcs, NULL, 0, 0, zcs->params, pledgedSrcSize);
}
size_t ZSTDMT_initCStream(ZSTDMT_CCtx* zcs, int compressionLevel) {
ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, 0);
return ZSTDMT_initCStream_internal(zcs, NULL, 0, NULL, params, 0);
}
static size_t ZSTDMT_createCompressionJob(ZSTDMT_CCtx* zcs, size_t srcSize, unsigned endFrame)
{
unsigned const jobID = zcs->nextJobID & zcs->jobIDMask;
DEBUGLOG(4, "preparing job %u to compress %u bytes with %u preload ",
zcs->nextJobID, (U32)srcSize, (U32)zcs->dictSize);
zcs->jobs[jobID].src = zcs->inBuff.buffer;
zcs->jobs[jobID].srcStart = zcs->inBuff.buffer.start;
zcs->jobs[jobID].srcSize = srcSize;
zcs->jobs[jobID].dictSize = zcs->dictSize;
assert(zcs->inBuff.filled >= srcSize + zcs->dictSize);
zcs->jobs[jobID].params = zcs->params;
/* do not calculate checksum within sections, but write it in header for first section */
if (zcs->nextJobID) zcs->jobs[jobID].params.fParams.checksumFlag = 0;
zcs->jobs[jobID].cdict = zcs->nextJobID==0 ? zcs->cdict : NULL;
zcs->jobs[jobID].fullFrameSize = zcs->frameContentSize;
zcs->jobs[jobID].dstBuff = g_nullBuffer;
zcs->jobs[jobID].cctxPool = zcs->cctxPool;
zcs->jobs[jobID].bufPool = zcs->bufPool;
zcs->jobs[jobID].firstChunk = (zcs->nextJobID==0);
zcs->jobs[jobID].lastChunk = endFrame;
zcs->jobs[jobID].jobCompleted = 0;
zcs->jobs[jobID].dstFlushed = 0;
zcs->jobs[jobID].jobCompleted_mutex = &zcs->jobCompleted_mutex;
zcs->jobs[jobID].jobCompleted_cond = &zcs->jobCompleted_cond;
if (zcs->params.fParams.checksumFlag)
XXH64_update(&zcs->xxhState, (const char*)zcs->inBuff.buffer.start + zcs->dictSize, srcSize);
/* get a new buffer for next input */
if (!endFrame) {
size_t const newDictSize = MIN(srcSize + zcs->dictSize, zcs->targetDictSize);
zcs->inBuff.buffer = ZSTDMT_getBuffer(zcs->bufPool);
if (zcs->inBuff.buffer.start == NULL) { /* not enough memory to allocate next input buffer */
zcs->jobs[jobID].jobCompleted = 1;
zcs->nextJobID++;
ZSTDMT_waitForAllJobsCompleted(zcs);
ZSTDMT_releaseAllJobResources(zcs);
return ERROR(memory_allocation);
}
zcs->inBuff.filled -= srcSize + zcs->dictSize - newDictSize;
memmove(zcs->inBuff.buffer.start,
(const char*)zcs->jobs[jobID].srcStart + zcs->dictSize + srcSize - newDictSize,
zcs->inBuff.filled);
zcs->dictSize = newDictSize;
} else { /* if (endFrame==1) */
zcs->inBuff.buffer = g_nullBuffer;
zcs->inBuff.filled = 0;
zcs->dictSize = 0;
zcs->frameEnded = 1;
if (zcs->nextJobID == 0) {
/* single chunk exception : checksum is calculated directly within worker thread */
zcs->params.fParams.checksumFlag = 0;
} }
DEBUGLOG(4, "posting job %u : %u bytes (end:%u) (note : doneJob = %u=>%u)",
zcs->nextJobID,
(U32)zcs->jobs[jobID].srcSize,
zcs->jobs[jobID].lastChunk,
zcs->doneJobID,
zcs->doneJobID & zcs->jobIDMask);
POOL_add(zcs->factory, ZSTDMT_compressChunk, &zcs->jobs[jobID]); /* this call is blocking when thread worker pool is exhausted */
zcs->nextJobID++;
return 0;
}
/* ZSTDMT_flushNextJob() :
* output : will be updated with amount of data flushed .
* blockToFlush : if >0, the function will block and wait if there is no data available to flush .
* @return : amount of data remaining within internal buffer, 1 if unknown but > 0, 0 if no more, or an error code */
static size_t ZSTDMT_flushNextJob(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, unsigned blockToFlush)
{
unsigned const wJobID = zcs->doneJobID & zcs->jobIDMask;
if (zcs->doneJobID == zcs->nextJobID) return 0; /* all flushed ! */
PTHREAD_MUTEX_LOCK(&zcs->jobCompleted_mutex);
while (zcs->jobs[wJobID].jobCompleted==0) {
DEBUGLOG(5, "waiting for jobCompleted signal from job %u", zcs->doneJobID);
if (!blockToFlush) { pthread_mutex_unlock(&zcs->jobCompleted_mutex); return 0; } /* nothing ready to be flushed => skip */
pthread_cond_wait(&zcs->jobCompleted_cond, &zcs->jobCompleted_mutex); /* block when nothing available to flush */
}
pthread_mutex_unlock(&zcs->jobCompleted_mutex);
/* compression job completed : output can be flushed */
{ ZSTDMT_jobDescription job = zcs->jobs[wJobID];
if (!job.jobScanned) {
if (ZSTD_isError(job.cSize)) {
DEBUGLOG(5, "compression error detected ");
ZSTDMT_waitForAllJobsCompleted(zcs);
ZSTDMT_releaseAllJobResources(zcs);
return job.cSize;
}
DEBUGLOG(5, "zcs->params.fParams.checksumFlag : %u ", zcs->params.fParams.checksumFlag);
if (zcs->params.fParams.checksumFlag) {
if (zcs->frameEnded && (zcs->doneJobID+1 == zcs->nextJobID)) { /* write checksum at end of last section */
U32 const checksum = (U32)XXH64_digest(&zcs->xxhState);
DEBUGLOG(5, "writing checksum : %08X \n", checksum);
MEM_writeLE32((char*)job.dstBuff.start + job.cSize, checksum);
job.cSize += 4;
zcs->jobs[wJobID].cSize += 4;
} }
zcs->jobs[wJobID].jobScanned = 1;
}
{ size_t const toWrite = MIN(job.cSize - job.dstFlushed, output->size - output->pos);
DEBUGLOG(5, "Flushing %u bytes from job %u ", (U32)toWrite, zcs->doneJobID);
memcpy((char*)output->dst + output->pos, (const char*)job.dstBuff.start + job.dstFlushed, toWrite);
output->pos += toWrite;
job.dstFlushed += toWrite;
}
if (job.dstFlushed == job.cSize) { /* output buffer fully flushed => move to next one */
ZSTDMT_releaseBuffer(zcs->bufPool, job.dstBuff);
zcs->jobs[wJobID].dstBuff = g_nullBuffer;
zcs->jobs[wJobID].jobCompleted = 0;
zcs->doneJobID++;
} else {
zcs->jobs[wJobID].dstFlushed = job.dstFlushed;
}
/* return value : how many bytes left in buffer ; fake it to 1 if unknown but >0 */
if (job.cSize > job.dstFlushed) return (job.cSize - job.dstFlushed);
if (zcs->doneJobID < zcs->nextJobID) return 1; /* still some buffer to flush */
zcs->allJobsCompleted = zcs->frameEnded; /* frame completed and entirely flushed */
return 0; /* everything flushed */
} }
/** ZSTDMT_compressStream_generic() :
* internal use only
* assumption : output and input are valid (pos <= size)
* @return : minimum amount of data remaining to flush, 0 if none */
size_t ZSTDMT_compressStream_generic(ZSTDMT_CCtx* mtctx,
ZSTD_outBuffer* output,
ZSTD_inBuffer* input,
ZSTD_EndDirective endOp)
{
size_t const newJobThreshold = mtctx->dictSize + mtctx->targetSectionSize;
assert(output->pos <= output->size);
assert(input->pos <= input->size);
if ((mtctx->frameEnded) && (endOp==ZSTD_e_continue)) {
/* current frame being ended. Only flush/end are allowed. Or start new frame with init */
return ERROR(stage_wrong);
}
if (mtctx->nbThreads==1) { /* delegate to single-thread (synchronous) */
return ZSTD_compressStream_generic(mtctx->cctxPool->cctx[0], output, input, endOp);
}
/* single-pass shortcut (note : this is synchronous-mode) */
if ( (mtctx->nextJobID==0) /* just started */
&& (mtctx->inBuff.filled==0) /* nothing buffered */
&& (endOp==ZSTD_e_end) /* end order */
&& (output->size - output->pos >= ZSTD_compressBound(input->size - input->pos)) ) { /* enough room */
size_t const cSize = ZSTDMT_compress_advanced(mtctx,
(char*)output->dst + output->pos, output->size - output->pos,
(const char*)input->src + input->pos, input->size - input->pos,
mtctx->cdict, mtctx->params, mtctx->overlapLog);
if (ZSTD_isError(cSize)) return cSize;
input->pos = input->size;
output->pos += cSize;
ZSTDMT_releaseBuffer(mtctx->bufPool, mtctx->inBuff.buffer); /* was allocated in initStream */
mtctx->allJobsCompleted = 1;
mtctx->frameEnded = 1;
return 0;
}
/* fill input buffer */
if (input->size > input->pos) { /* support NULL input */
if (mtctx->inBuff.buffer.start == NULL) {
mtctx->inBuff.buffer = ZSTDMT_getBuffer(mtctx->bufPool);
if (mtctx->inBuff.buffer.start == NULL) return ERROR(memory_allocation);
mtctx->inBuff.filled = 0;
}
{ size_t const toLoad = MIN(input->size - input->pos, mtctx->inBuffSize - mtctx->inBuff.filled);
DEBUGLOG(5, "inBuff:%08X; inBuffSize=%u; ToCopy=%u", (U32)(size_t)mtctx->inBuff.buffer.start, (U32)mtctx->inBuffSize, (U32)toLoad);
memcpy((char*)mtctx->inBuff.buffer.start + mtctx->inBuff.filled, (const char*)input->src + input->pos, toLoad);
input->pos += toLoad;
mtctx->inBuff.filled += toLoad;
} }
if ( (mtctx->inBuff.filled >= newJobThreshold) /* filled enough : let's compress */
&& (mtctx->nextJobID <= mtctx->doneJobID + mtctx->jobIDMask) ) { /* avoid overwriting job round buffer */
CHECK_F( ZSTDMT_createCompressionJob(mtctx, mtctx->targetSectionSize, 0 /* endFrame */) );
}
/* check for potential compressed data ready to be flushed */
CHECK_F( ZSTDMT_flushNextJob(mtctx, output, (mtctx->inBuff.filled == mtctx->inBuffSize) /* blockToFlush */) ); /* block if it wasn't possible to create new job due to saturation */
if (input->pos < input->size) /* input not consumed : do not flush yet */
endOp = ZSTD_e_continue;
switch(endOp)
{
case ZSTD_e_flush:
return ZSTDMT_flushStream(mtctx, output);
case ZSTD_e_end:
return ZSTDMT_endStream(mtctx, output);
case ZSTD_e_continue:
return 1;
default:
return ERROR(GENERIC); /* invalid endDirective */
}
}
size_t ZSTDMT_compressStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input)
{
CHECK_F( ZSTDMT_compressStream_generic(zcs, output, input, ZSTD_e_continue) );
/* recommended next input size : fill current input buffer */
return zcs->inBuffSize - zcs->inBuff.filled; /* note : could be zero when input buffer is fully filled and no more availability to create new job */
}
static size_t ZSTDMT_flushStream_internal(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, unsigned endFrame)
{
size_t const srcSize = zcs->inBuff.filled - zcs->dictSize;
if ( ((srcSize > 0) || (endFrame && !zcs->frameEnded))
&& (zcs->nextJobID <= zcs->doneJobID + zcs->jobIDMask) ) {
CHECK_F( ZSTDMT_createCompressionJob(zcs, srcSize, endFrame) );
}
/* check if there is any data available to flush */
return ZSTDMT_flushNextJob(zcs, output, 1 /* blockToFlush */);
}
size_t ZSTDMT_flushStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output)
{
DEBUGLOG(5, "ZSTDMT_flushStream");
if (zcs->nbThreads==1)
return ZSTD_flushStream(zcs->cctxPool->cctx[0], output);
return ZSTDMT_flushStream_internal(zcs, output, 0 /* endFrame */);
}
size_t ZSTDMT_endStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output)
{
DEBUGLOG(4, "ZSTDMT_endStream");
if (zcs->nbThreads==1)
return ZSTD_endStream(zcs->cctxPool->cctx[0], output);
return ZSTDMT_flushStream_internal(zcs, output, 1 /* endFrame */);
}