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1/*2 * Copyright (c) Yann Collet, Facebook, Inc.3 * All rights reserved.4 *5 * This source code is licensed under both the BSD-style license (found in the6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found7 * 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#ifndef ZSTD_CWKSP_H12#define ZSTD_CWKSP_H13 14/*-*************************************15*  Dependencies16***************************************/17#include "../common/zstd_internal.h"18 19 20/*-*************************************21*  Constants22***************************************/23 24/* Since the workspace is effectively its own little malloc implementation /25 * arena, when we run under ASAN, we should similarly insert redzones between26 * each internal element of the workspace, so ASAN will catch overruns that27 * reach outside an object but that stay inside the workspace.28 *29 * This defines the size of that redzone.30 */31#ifndef ZSTD_CWKSP_ASAN_REDZONE_SIZE32#define ZSTD_CWKSP_ASAN_REDZONE_SIZE 12833#endif34 35 36/* Set our tables and aligneds to align by 64 bytes */37#define ZSTD_CWKSP_ALIGNMENT_BYTES 6438 39/*-*************************************40*  Structures41***************************************/42typedef enum {43    ZSTD_cwksp_alloc_objects,44    ZSTD_cwksp_alloc_buffers,45    ZSTD_cwksp_alloc_aligned46} ZSTD_cwksp_alloc_phase_e;47 48/*49 * Used to describe whether the workspace is statically allocated (and will not50 * necessarily ever be freed), or if it's dynamically allocated and we can51 * expect a well-formed caller to free this.52 */53typedef enum {54    ZSTD_cwksp_dynamic_alloc,55    ZSTD_cwksp_static_alloc56} ZSTD_cwksp_static_alloc_e;57 58/*59 * Zstd fits all its internal datastructures into a single continuous buffer,60 * so that it only needs to perform a single OS allocation (or so that a buffer61 * can be provided to it and it can perform no allocations at all). This buffer62 * is called the workspace.63 *64 * Several optimizations complicate that process of allocating memory ranges65 * from this workspace for each internal datastructure:66 *67 * - These different internal datastructures have different setup requirements:68 *69 *   - The static objects need to be cleared once and can then be trivially70 *     reused for each compression.71 *72 *   - Various buffers don't need to be initialized at all--they are always73 *     written into before they're read.74 *75 *   - The matchstate tables have a unique requirement that they don't need76 *     their memory to be totally cleared, but they do need the memory to have77 *     some bound, i.e., a guarantee that all values in the memory they've been78 *     allocated is less than some maximum value (which is the starting value79 *     for the indices that they will then use for compression). When this80 *     guarantee is provided to them, they can use the memory without any setup81 *     work. When it can't, they have to clear the area.82 *83 * - These buffers also have different alignment requirements.84 *85 * - We would like to reuse the objects in the workspace for multiple86 *   compressions without having to perform any expensive reallocation or87 *   reinitialization work.88 *89 * - We would like to be able to efficiently reuse the workspace across90 *   multiple compressions **even when the compression parameters change** and91 *   we need to resize some of the objects (where possible).92 *93 * To attempt to manage this buffer, given these constraints, the ZSTD_cwksp94 * abstraction was created. It works as follows:95 *96 * Workspace Layout:97 *98 * [                        ... workspace ...                         ]99 * [objects][tables ... ->] free space [<- ... aligned][<- ... buffers]100 *101 * The various objects that live in the workspace are divided into the102 * following categories, and are allocated separately:103 *104 * - Static objects: this is optionally the enclosing ZSTD_CCtx or ZSTD_CDict,105 *   so that literally everything fits in a single buffer. Note: if present,106 *   this must be the first object in the workspace, since ZSTD_customFree{CCtx,107 *   CDict}() rely on a pointer comparison to see whether one or two frees are108 *   required.109 *110 * - Fixed size objects: these are fixed-size, fixed-count objects that are111 *   nonetheless "dynamically" allocated in the workspace so that we can112 *   control how they're initialized separately from the broader ZSTD_CCtx.113 *   Examples:114 *   - Entropy Workspace115 *   - 2 x ZSTD_compressedBlockState_t116 *   - CDict dictionary contents117 *118 * - Tables: these are any of several different datastructures (hash tables,119 *   chain tables, binary trees) that all respect a common format: they are120 *   uint32_t arrays, all of whose values are between 0 and (nextSrc - base).121 *   Their sizes depend on the cparams. These tables are 64-byte aligned.122 *123 * - Aligned: these buffers are used for various purposes that require 4 byte124 *   alignment, but don't require any initialization before they're used. These125 *   buffers are each aligned to 64 bytes.126 *127 * - Buffers: these buffers are used for various purposes that don't require128 *   any alignment or initialization before they're used. This means they can129 *   be moved around at no cost for a new compression.130 *131 * Allocating Memory:132 *133 * The various types of objects must be allocated in order, so they can be134 * correctly packed into the workspace buffer. That order is:135 *136 * 1. Objects137 * 2. Buffers138 * 3. Aligned/Tables139 *140 * Attempts to reserve objects of different types out of order will fail.141 */142typedef struct {143    void* workspace;144    void* workspaceEnd;145 146    void* objectEnd;147    void* tableEnd;148    void* tableValidEnd;149    void* allocStart;150 151    BYTE allocFailed;152    int workspaceOversizedDuration;153    ZSTD_cwksp_alloc_phase_e phase;154    ZSTD_cwksp_static_alloc_e isStatic;155} ZSTD_cwksp;156 157/*-*************************************158*  Functions159***************************************/160 161MEM_STATIC size_t ZSTD_cwksp_available_space(ZSTD_cwksp* ws);162 163MEM_STATIC void ZSTD_cwksp_assert_internal_consistency(ZSTD_cwksp* ws) {164    (void)ws;165    assert(ws->workspace <= ws->objectEnd);166    assert(ws->objectEnd <= ws->tableEnd);167    assert(ws->objectEnd <= ws->tableValidEnd);168    assert(ws->tableEnd <= ws->allocStart);169    assert(ws->tableValidEnd <= ws->allocStart);170    assert(ws->allocStart <= ws->workspaceEnd);171}172 173/*174 * Align must be a power of 2.175 */176MEM_STATIC size_t ZSTD_cwksp_align(size_t size, size_t const align) {177    size_t const mask = align - 1;178    assert((align & mask) == 0);179    return (size + mask) & ~mask;180}181 182/*183 * Use this to determine how much space in the workspace we will consume to184 * allocate this object. (Normally it should be exactly the size of the object,185 * but under special conditions, like ASAN, where we pad each object, it might186 * be larger.)187 *188 * Since tables aren't currently redzoned, you don't need to call through this189 * to figure out how much space you need for the matchState tables. Everything190 * else is though.191 *192 * Do not use for sizing aligned buffers. Instead, use ZSTD_cwksp_aligned_alloc_size().193 */194MEM_STATIC size_t ZSTD_cwksp_alloc_size(size_t size) {195    if (size == 0)196        return 0;197    return size;198}199 200/*201 * Returns an adjusted alloc size that is the nearest larger multiple of 64 bytes.202 * Used to determine the number of bytes required for a given "aligned".203 */204MEM_STATIC size_t ZSTD_cwksp_aligned_alloc_size(size_t size) {205    return ZSTD_cwksp_alloc_size(ZSTD_cwksp_align(size, ZSTD_CWKSP_ALIGNMENT_BYTES));206}207 208/*209 * Returns the amount of additional space the cwksp must allocate210 * for internal purposes (currently only alignment).211 */212MEM_STATIC size_t ZSTD_cwksp_slack_space_required(void) {213    /* For alignment, the wksp will always allocate an additional n_1=[1, 64] bytes214     * to align the beginning of tables section, as well as another n_2=[0, 63] bytes215     * to align the beginning of the aligned section.216     *217     * n_1 + n_2 == 64 bytes if the cwksp is freshly allocated, due to tables and218     * aligneds being sized in multiples of 64 bytes.219     */220    size_t const slackSpace = ZSTD_CWKSP_ALIGNMENT_BYTES;221    return slackSpace;222}223 224 225/*226 * Return the number of additional bytes required to align a pointer to the given number of bytes.227 * alignBytes must be a power of two.228 */229MEM_STATIC size_t ZSTD_cwksp_bytes_to_align_ptr(void* ptr, const size_t alignBytes) {230    size_t const alignBytesMask = alignBytes - 1;231    size_t const bytes = (alignBytes - ((size_t)ptr & (alignBytesMask))) & alignBytesMask;232    assert((alignBytes & alignBytesMask) == 0);233    assert(bytes != ZSTD_CWKSP_ALIGNMENT_BYTES);234    return bytes;235}236 237/*238 * Internal function. Do not use directly.239 * Reserves the given number of bytes within the aligned/buffer segment of the wksp,240 * which counts from the end of the wksp (as opposed to the object/table segment).241 *242 * Returns a pointer to the beginning of that space.243 */244MEM_STATIC void*245ZSTD_cwksp_reserve_internal_buffer_space(ZSTD_cwksp* ws, size_t const bytes)246{247    void* const alloc = (BYTE*)ws->allocStart - bytes;248    void* const bottom = ws->tableEnd;249    DEBUGLOG(5, "cwksp: reserving %p %zd bytes, %zd bytes remaining",250        alloc, bytes, ZSTD_cwksp_available_space(ws) - bytes);251    ZSTD_cwksp_assert_internal_consistency(ws);252    assert(alloc >= bottom);253    if (alloc < bottom) {254        DEBUGLOG(4, "cwksp: alloc failed!");255        ws->allocFailed = 1;256        return NULL;257    }258    /* the area is reserved from the end of wksp.259     * If it overlaps with tableValidEnd, it voids guarantees on values' range */260    if (alloc < ws->tableValidEnd) {261        ws->tableValidEnd = alloc;262    }263    ws->allocStart = alloc;264    return alloc;265}266 267/*268 * Moves the cwksp to the next phase, and does any necessary allocations.269 * cwksp initialization must necessarily go through each phase in order.270 * Returns a 0 on success, or zstd error271 */272MEM_STATIC size_t273ZSTD_cwksp_internal_advance_phase(ZSTD_cwksp* ws, ZSTD_cwksp_alloc_phase_e phase)274{275    assert(phase >= ws->phase);276    if (phase > ws->phase) {277        /* Going from allocating objects to allocating buffers */278        if (ws->phase < ZSTD_cwksp_alloc_buffers &&279                phase >= ZSTD_cwksp_alloc_buffers) {280            ws->tableValidEnd = ws->objectEnd;281        }282 283        /* Going from allocating buffers to allocating aligneds/tables */284        if (ws->phase < ZSTD_cwksp_alloc_aligned &&285                phase >= ZSTD_cwksp_alloc_aligned) {286            {   /* Align the start of the "aligned" to 64 bytes. Use [1, 64] bytes. */287                size_t const bytesToAlign =288                    ZSTD_CWKSP_ALIGNMENT_BYTES - ZSTD_cwksp_bytes_to_align_ptr(ws->allocStart, ZSTD_CWKSP_ALIGNMENT_BYTES);289                DEBUGLOG(5, "reserving aligned alignment addtl space: %zu", bytesToAlign);290                ZSTD_STATIC_ASSERT((ZSTD_CWKSP_ALIGNMENT_BYTES & (ZSTD_CWKSP_ALIGNMENT_BYTES - 1)) == 0); /* power of 2 */291                RETURN_ERROR_IF(!ZSTD_cwksp_reserve_internal_buffer_space(ws, bytesToAlign),292                                memory_allocation, "aligned phase - alignment initial allocation failed!");293            }294            {   /* Align the start of the tables to 64 bytes. Use [0, 63] bytes */295                void* const alloc = ws->objectEnd;296                size_t const bytesToAlign = ZSTD_cwksp_bytes_to_align_ptr(alloc, ZSTD_CWKSP_ALIGNMENT_BYTES);297                void* const objectEnd = (BYTE*)alloc + bytesToAlign;298                DEBUGLOG(5, "reserving table alignment addtl space: %zu", bytesToAlign);299                RETURN_ERROR_IF(objectEnd > ws->workspaceEnd, memory_allocation,300                                "table phase - alignment initial allocation failed!");301                ws->objectEnd = objectEnd;302                ws->tableEnd = objectEnd;  /* table area starts being empty */303                if (ws->tableValidEnd < ws->tableEnd) {304                    ws->tableValidEnd = ws->tableEnd;305        }   }   }306        ws->phase = phase;307        ZSTD_cwksp_assert_internal_consistency(ws);308    }309    return 0;310}311 312/*313 * Returns whether this object/buffer/etc was allocated in this workspace.314 */315MEM_STATIC int ZSTD_cwksp_owns_buffer(const ZSTD_cwksp* ws, const void* ptr)316{317    return (ptr != NULL) && (ws->workspace <= ptr) && (ptr <= ws->workspaceEnd);318}319 320/*321 * Internal function. Do not use directly.322 */323MEM_STATIC void*324ZSTD_cwksp_reserve_internal(ZSTD_cwksp* ws, size_t bytes, ZSTD_cwksp_alloc_phase_e phase)325{326    void* alloc;327    if (ZSTD_isError(ZSTD_cwksp_internal_advance_phase(ws, phase)) || bytes == 0) {328        return NULL;329    }330 331 332    alloc = ZSTD_cwksp_reserve_internal_buffer_space(ws, bytes);333 334 335    return alloc;336}337 338/*339 * Reserves and returns unaligned memory.340 */341MEM_STATIC BYTE* ZSTD_cwksp_reserve_buffer(ZSTD_cwksp* ws, size_t bytes)342{343    return (BYTE*)ZSTD_cwksp_reserve_internal(ws, bytes, ZSTD_cwksp_alloc_buffers);344}345 346/*347 * Reserves and returns memory sized on and aligned on ZSTD_CWKSP_ALIGNMENT_BYTES (64 bytes).348 */349MEM_STATIC void* ZSTD_cwksp_reserve_aligned(ZSTD_cwksp* ws, size_t bytes)350{351    void* ptr = ZSTD_cwksp_reserve_internal(ws, ZSTD_cwksp_align(bytes, ZSTD_CWKSP_ALIGNMENT_BYTES),352                                            ZSTD_cwksp_alloc_aligned);353    assert(((size_t)ptr & (ZSTD_CWKSP_ALIGNMENT_BYTES-1))== 0);354    return ptr;355}356 357/*358 * Aligned on 64 bytes. These buffers have the special property that359 * their values remain constrained, allowing us to re-use them without360 * memset()-ing them.361 */362MEM_STATIC void* ZSTD_cwksp_reserve_table(ZSTD_cwksp* ws, size_t bytes)363{364    const ZSTD_cwksp_alloc_phase_e phase = ZSTD_cwksp_alloc_aligned;365    void* alloc;366    void* end;367    void* top;368 369    if (ZSTD_isError(ZSTD_cwksp_internal_advance_phase(ws, phase))) {370        return NULL;371    }372    alloc = ws->tableEnd;373    end = (BYTE *)alloc + bytes;374    top = ws->allocStart;375 376    DEBUGLOG(5, "cwksp: reserving %p table %zd bytes, %zd bytes remaining",377        alloc, bytes, ZSTD_cwksp_available_space(ws) - bytes);378    assert((bytes & (sizeof(U32)-1)) == 0);379    ZSTD_cwksp_assert_internal_consistency(ws);380    assert(end <= top);381    if (end > top) {382        DEBUGLOG(4, "cwksp: table alloc failed!");383        ws->allocFailed = 1;384        return NULL;385    }386    ws->tableEnd = end;387 388 389    assert((bytes & (ZSTD_CWKSP_ALIGNMENT_BYTES-1)) == 0);390    assert(((size_t)alloc & (ZSTD_CWKSP_ALIGNMENT_BYTES-1))== 0);391    return alloc;392}393 394/*395 * Aligned on sizeof(void*).396 * Note : should happen only once, at workspace first initialization397 */398MEM_STATIC void* ZSTD_cwksp_reserve_object(ZSTD_cwksp* ws, size_t bytes)399{400    size_t const roundedBytes = ZSTD_cwksp_align(bytes, sizeof(void*));401    void* alloc = ws->objectEnd;402    void* end = (BYTE*)alloc + roundedBytes;403 404 405    DEBUGLOG(4,406        "cwksp: reserving %p object %zd bytes (rounded to %zd), %zd bytes remaining",407        alloc, bytes, roundedBytes, ZSTD_cwksp_available_space(ws) - roundedBytes);408    assert((size_t)alloc % ZSTD_ALIGNOF(void*) == 0);409    assert(bytes % ZSTD_ALIGNOF(void*) == 0);410    ZSTD_cwksp_assert_internal_consistency(ws);411    /* we must be in the first phase, no advance is possible */412    if (ws->phase != ZSTD_cwksp_alloc_objects || end > ws->workspaceEnd) {413        DEBUGLOG(3, "cwksp: object alloc failed!");414        ws->allocFailed = 1;415        return NULL;416    }417    ws->objectEnd = end;418    ws->tableEnd = end;419    ws->tableValidEnd = end;420 421 422    return alloc;423}424 425MEM_STATIC void ZSTD_cwksp_mark_tables_dirty(ZSTD_cwksp* ws)426{427    DEBUGLOG(4, "cwksp: ZSTD_cwksp_mark_tables_dirty");428 429 430    assert(ws->tableValidEnd >= ws->objectEnd);431    assert(ws->tableValidEnd <= ws->allocStart);432    ws->tableValidEnd = ws->objectEnd;433    ZSTD_cwksp_assert_internal_consistency(ws);434}435 436MEM_STATIC void ZSTD_cwksp_mark_tables_clean(ZSTD_cwksp* ws) {437    DEBUGLOG(4, "cwksp: ZSTD_cwksp_mark_tables_clean");438    assert(ws->tableValidEnd >= ws->objectEnd);439    assert(ws->tableValidEnd <= ws->allocStart);440    if (ws->tableValidEnd < ws->tableEnd) {441        ws->tableValidEnd = ws->tableEnd;442    }443    ZSTD_cwksp_assert_internal_consistency(ws);444}445 446/*447 * Zero the part of the allocated tables not already marked clean.448 */449MEM_STATIC void ZSTD_cwksp_clean_tables(ZSTD_cwksp* ws) {450    DEBUGLOG(4, "cwksp: ZSTD_cwksp_clean_tables");451    assert(ws->tableValidEnd >= ws->objectEnd);452    assert(ws->tableValidEnd <= ws->allocStart);453    if (ws->tableValidEnd < ws->tableEnd) {454        ZSTD_memset(ws->tableValidEnd, 0, (BYTE*)ws->tableEnd - (BYTE*)ws->tableValidEnd);455    }456    ZSTD_cwksp_mark_tables_clean(ws);457}458 459/*460 * Invalidates table allocations.461 * All other allocations remain valid.462 */463MEM_STATIC void ZSTD_cwksp_clear_tables(ZSTD_cwksp* ws) {464    DEBUGLOG(4, "cwksp: clearing tables!");465 466 467    ws->tableEnd = ws->objectEnd;468    ZSTD_cwksp_assert_internal_consistency(ws);469}470 471/*472 * Invalidates all buffer, aligned, and table allocations.473 * Object allocations remain valid.474 */475MEM_STATIC void ZSTD_cwksp_clear(ZSTD_cwksp* ws) {476    DEBUGLOG(4, "cwksp: clearing!");477 478 479 480    ws->tableEnd = ws->objectEnd;481    ws->allocStart = ws->workspaceEnd;482    ws->allocFailed = 0;483    if (ws->phase > ZSTD_cwksp_alloc_buffers) {484        ws->phase = ZSTD_cwksp_alloc_buffers;485    }486    ZSTD_cwksp_assert_internal_consistency(ws);487}488 489/*490 * The provided workspace takes ownership of the buffer [start, start+size).491 * Any existing values in the workspace are ignored (the previously managed492 * buffer, if present, must be separately freed).493 */494MEM_STATIC void ZSTD_cwksp_init(ZSTD_cwksp* ws, void* start, size_t size, ZSTD_cwksp_static_alloc_e isStatic) {495    DEBUGLOG(4, "cwksp: init'ing workspace with %zd bytes", size);496    assert(((size_t)start & (sizeof(void*)-1)) == 0); /* ensure correct alignment */497    ws->workspace = start;498    ws->workspaceEnd = (BYTE*)start + size;499    ws->objectEnd = ws->workspace;500    ws->tableValidEnd = ws->objectEnd;501    ws->phase = ZSTD_cwksp_alloc_objects;502    ws->isStatic = isStatic;503    ZSTD_cwksp_clear(ws);504    ws->workspaceOversizedDuration = 0;505    ZSTD_cwksp_assert_internal_consistency(ws);506}507 508MEM_STATIC size_t ZSTD_cwksp_create(ZSTD_cwksp* ws, size_t size, ZSTD_customMem customMem) {509    void* workspace = ZSTD_customMalloc(size, customMem);510    DEBUGLOG(4, "cwksp: creating new workspace with %zd bytes", size);511    RETURN_ERROR_IF(workspace == NULL, memory_allocation, "NULL pointer!");512    ZSTD_cwksp_init(ws, workspace, size, ZSTD_cwksp_dynamic_alloc);513    return 0;514}515 516MEM_STATIC void ZSTD_cwksp_free(ZSTD_cwksp* ws, ZSTD_customMem customMem) {517    void *ptr = ws->workspace;518    DEBUGLOG(4, "cwksp: freeing workspace");519    ZSTD_memset(ws, 0, sizeof(ZSTD_cwksp));520    ZSTD_customFree(ptr, customMem);521}522 523/*524 * Moves the management of a workspace from one cwksp to another. The src cwksp525 * is left in an invalid state (src must be re-init()'ed before it's used again).526 */527MEM_STATIC void ZSTD_cwksp_move(ZSTD_cwksp* dst, ZSTD_cwksp* src) {528    *dst = *src;529    ZSTD_memset(src, 0, sizeof(ZSTD_cwksp));530}531 532MEM_STATIC size_t ZSTD_cwksp_sizeof(const ZSTD_cwksp* ws) {533    return (size_t)((BYTE*)ws->workspaceEnd - (BYTE*)ws->workspace);534}535 536MEM_STATIC size_t ZSTD_cwksp_used(const ZSTD_cwksp* ws) {537    return (size_t)((BYTE*)ws->tableEnd - (BYTE*)ws->workspace)538         + (size_t)((BYTE*)ws->workspaceEnd - (BYTE*)ws->allocStart);539}540 541MEM_STATIC int ZSTD_cwksp_reserve_failed(const ZSTD_cwksp* ws) {542    return ws->allocFailed;543}544 545/*-*************************************546*  Functions Checking Free Space547***************************************/548 549/* ZSTD_alignmentSpaceWithinBounds() :550 * Returns if the estimated space needed for a wksp is within an acceptable limit of the551 * actual amount of space used.552 */553MEM_STATIC int ZSTD_cwksp_estimated_space_within_bounds(const ZSTD_cwksp* const ws,554                                                        size_t const estimatedSpace, int resizedWorkspace) {555    if (resizedWorkspace) {556        /* Resized/newly allocated wksp should have exact bounds */557        return ZSTD_cwksp_used(ws) == estimatedSpace;558    } else {559        /* Due to alignment, when reusing a workspace, we can actually consume 63 fewer or more bytes560         * than estimatedSpace. See the comments in zstd_cwksp.h for details.561         */562        return (ZSTD_cwksp_used(ws) >= estimatedSpace - 63) && (ZSTD_cwksp_used(ws) <= estimatedSpace + 63);563    }564}565 566 567MEM_STATIC size_t ZSTD_cwksp_available_space(ZSTD_cwksp* ws) {568    return (size_t)((BYTE*)ws->allocStart - (BYTE*)ws->tableEnd);569}570 571MEM_STATIC int ZSTD_cwksp_check_available(ZSTD_cwksp* ws, size_t additionalNeededSpace) {572    return ZSTD_cwksp_available_space(ws) >= additionalNeededSpace;573}574 575MEM_STATIC int ZSTD_cwksp_check_too_large(ZSTD_cwksp* ws, size_t additionalNeededSpace) {576    return ZSTD_cwksp_check_available(577        ws, additionalNeededSpace * ZSTD_WORKSPACETOOLARGE_FACTOR);578}579 580MEM_STATIC int ZSTD_cwksp_check_wasteful(ZSTD_cwksp* ws, size_t additionalNeededSpace) {581    return ZSTD_cwksp_check_too_large(ws, additionalNeededSpace)582        && ws->workspaceOversizedDuration > ZSTD_WORKSPACETOOLARGE_MAXDURATION;583}584 585MEM_STATIC void ZSTD_cwksp_bump_oversized_duration(586        ZSTD_cwksp* ws, size_t additionalNeededSpace) {587    if (ZSTD_cwksp_check_too_large(ws, additionalNeededSpace)) {588        ws->workspaceOversizedDuration++;589    } else {590        ws->workspaceOversizedDuration = 0;591    }592}593 594 595#endif /* ZSTD_CWKSP_H */596