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-rw-r--r--Utilities/cmzstd/lib/compress/zstd_cwksp.h271
1 files changed, 204 insertions, 67 deletions
diff --git a/Utilities/cmzstd/lib/compress/zstd_cwksp.h b/Utilities/cmzstd/lib/compress/zstd_cwksp.h
index a25c9263b7..2656d26ca2 100644
--- a/Utilities/cmzstd/lib/compress/zstd_cwksp.h
+++ b/Utilities/cmzstd/lib/compress/zstd_cwksp.h
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc.
+ * Copyright (c) Yann Collet, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under both the BSD-style license (found in the
@@ -35,6 +35,10 @@ extern "C" {
#define ZSTD_CWKSP_ASAN_REDZONE_SIZE 128
#endif
+
+/* Set our tables and aligneds to align by 64 bytes */
+#define ZSTD_CWKSP_ALIGNMENT_BYTES 64
+
/*-*************************************
* Structures
***************************************/
@@ -45,6 +49,16 @@ typedef enum {
} ZSTD_cwksp_alloc_phase_e;
/**
+ * Used to describe whether the workspace is statically allocated (and will not
+ * necessarily ever be freed), or if it's dynamically allocated and we can
+ * expect a well-formed caller to free this.
+ */
+typedef enum {
+ ZSTD_cwksp_dynamic_alloc,
+ ZSTD_cwksp_static_alloc
+} ZSTD_cwksp_static_alloc_e;
+
+/**
* Zstd fits all its internal datastructures into a single continuous buffer,
* so that it only needs to perform a single OS allocation (or so that a buffer
* can be provided to it and it can perform no allocations at all). This buffer
@@ -92,7 +106,7 @@ typedef enum {
*
* - Static objects: this is optionally the enclosing ZSTD_CCtx or ZSTD_CDict,
* so that literally everything fits in a single buffer. Note: if present,
- * this must be the first object in the workspace, since ZSTD_free{CCtx,
+ * this must be the first object in the workspace, since ZSTD_customFree{CCtx,
* CDict}() rely on a pointer comparison to see whether one or two frees are
* required.
*
@@ -107,10 +121,11 @@ typedef enum {
* - Tables: these are any of several different datastructures (hash tables,
* chain tables, binary trees) that all respect a common format: they are
* uint32_t arrays, all of whose values are between 0 and (nextSrc - base).
- * Their sizes depend on the cparams.
+ * Their sizes depend on the cparams. These tables are 64-byte aligned.
*
* - Aligned: these buffers are used for various purposes that require 4 byte
- * alignment, but don't require any initialization before they're used.
+ * alignment, but don't require any initialization before they're used. These
+ * buffers are each aligned to 64 bytes.
*
* - Buffers: these buffers are used for various purposes that don't require
* any alignment or initialization before they're used. This means they can
@@ -123,8 +138,7 @@ typedef enum {
*
* 1. Objects
* 2. Buffers
- * 3. Aligned
- * 4. Tables
+ * 3. Aligned/Tables
*
* Attempts to reserve objects of different types out of order will fail.
*/
@@ -137,9 +151,10 @@ typedef struct {
void* tableValidEnd;
void* allocStart;
- int allocFailed;
+ BYTE allocFailed;
int workspaceOversizedDuration;
ZSTD_cwksp_alloc_phase_e phase;
+ ZSTD_cwksp_static_alloc_e isStatic;
} ZSTD_cwksp;
/*-*************************************
@@ -176,39 +191,123 @@ MEM_STATIC size_t ZSTD_cwksp_align(size_t size, size_t const align) {
* Since tables aren't currently redzoned, you don't need to call through this
* to figure out how much space you need for the matchState tables. Everything
* else is though.
+ *
+ * Do not use for sizing aligned buffers. Instead, use ZSTD_cwksp_aligned_alloc_size().
*/
MEM_STATIC size_t ZSTD_cwksp_alloc_size(size_t size) {
-#if defined (ADDRESS_SANITIZER) && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
+ if (size == 0)
+ return 0;
+#if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
return size + 2 * ZSTD_CWKSP_ASAN_REDZONE_SIZE;
#else
return size;
#endif
}
-MEM_STATIC void ZSTD_cwksp_internal_advance_phase(
+/**
+ * Returns an adjusted alloc size that is the nearest larger multiple of 64 bytes.
+ * Used to determine the number of bytes required for a given "aligned".
+ */
+MEM_STATIC size_t ZSTD_cwksp_aligned_alloc_size(size_t size) {
+ return ZSTD_cwksp_alloc_size(ZSTD_cwksp_align(size, ZSTD_CWKSP_ALIGNMENT_BYTES));
+}
+
+/**
+ * Returns the amount of additional space the cwksp must allocate
+ * for internal purposes (currently only alignment).
+ */
+MEM_STATIC size_t ZSTD_cwksp_slack_space_required(void) {
+ /* For alignment, the wksp will always allocate an additional n_1=[1, 64] bytes
+ * to align the beginning of tables section, as well as another n_2=[0, 63] bytes
+ * to align the beginning of the aligned secion.
+ *
+ * n_1 + n_2 == 64 bytes if the cwksp is freshly allocated, due to tables and
+ * aligneds being sized in multiples of 64 bytes.
+ */
+ size_t const slackSpace = ZSTD_CWKSP_ALIGNMENT_BYTES;
+ return slackSpace;
+}
+
+
+/**
+ * Return the number of additional bytes required to align a pointer to the given number of bytes.
+ * alignBytes must be a power of two.
+ */
+MEM_STATIC size_t ZSTD_cwksp_bytes_to_align_ptr(void* ptr, const size_t alignBytes) {
+ size_t const alignBytesMask = alignBytes - 1;
+ size_t const bytes = (alignBytes - ((size_t)ptr & (alignBytesMask))) & alignBytesMask;
+ assert((alignBytes & alignBytesMask) == 0);
+ assert(bytes != ZSTD_CWKSP_ALIGNMENT_BYTES);
+ return bytes;
+}
+
+/**
+ * Internal function. Do not use directly.
+ * Reserves the given number of bytes within the aligned/buffer segment of the wksp, which
+ * counts from the end of the wksp. (as opposed to the object/table segment)
+ *
+ * Returns a pointer to the beginning of that space.
+ */
+MEM_STATIC void* ZSTD_cwksp_reserve_internal_buffer_space(ZSTD_cwksp* ws, size_t const bytes) {
+ void* const alloc = (BYTE*)ws->allocStart - bytes;
+ void* const bottom = ws->tableEnd;
+ DEBUGLOG(5, "cwksp: reserving %p %zd bytes, %zd bytes remaining",
+ alloc, bytes, ZSTD_cwksp_available_space(ws) - bytes);
+ ZSTD_cwksp_assert_internal_consistency(ws);
+ assert(alloc >= bottom);
+ if (alloc < bottom) {
+ DEBUGLOG(4, "cwksp: alloc failed!");
+ ws->allocFailed = 1;
+ return NULL;
+ }
+ if (alloc < ws->tableValidEnd) {
+ ws->tableValidEnd = alloc;
+ }
+ ws->allocStart = alloc;
+ return alloc;
+}
+
+/**
+ * Moves the cwksp to the next phase, and does any necessary allocations.
+ * Returns a 0 on success, or zstd error
+ */
+MEM_STATIC size_t ZSTD_cwksp_internal_advance_phase(
ZSTD_cwksp* ws, ZSTD_cwksp_alloc_phase_e phase) {
assert(phase >= ws->phase);
if (phase > ws->phase) {
+ /* Going from allocating objects to allocating buffers */
if (ws->phase < ZSTD_cwksp_alloc_buffers &&
phase >= ZSTD_cwksp_alloc_buffers) {
ws->tableValidEnd = ws->objectEnd;
}
+
+ /* Going from allocating buffers to allocating aligneds/tables */
if (ws->phase < ZSTD_cwksp_alloc_aligned &&
phase >= ZSTD_cwksp_alloc_aligned) {
- /* If unaligned allocations down from a too-large top have left us
- * unaligned, we need to realign our alloc ptr. Technically, this
- * can consume space that is unaccounted for in the neededSpace
- * calculation. However, I believe this can only happen when the
- * workspace is too large, and specifically when it is too large
- * by a larger margin than the space that will be consumed. */
- /* TODO: cleaner, compiler warning friendly way to do this??? */
- ws->allocStart = (BYTE*)ws->allocStart - ((size_t)ws->allocStart & (sizeof(U32)-1));
- if (ws->allocStart < ws->tableValidEnd) {
- ws->tableValidEnd = ws->allocStart;
+ { /* Align the start of the "aligned" to 64 bytes. Use [1, 64] bytes. */
+ size_t const bytesToAlign =
+ ZSTD_CWKSP_ALIGNMENT_BYTES - ZSTD_cwksp_bytes_to_align_ptr(ws->allocStart, ZSTD_CWKSP_ALIGNMENT_BYTES);
+ DEBUGLOG(5, "reserving aligned alignment addtl space: %zu", bytesToAlign);
+ ZSTD_STATIC_ASSERT((ZSTD_CWKSP_ALIGNMENT_BYTES & (ZSTD_CWKSP_ALIGNMENT_BYTES - 1)) == 0); /* power of 2 */
+ RETURN_ERROR_IF(!ZSTD_cwksp_reserve_internal_buffer_space(ws, bytesToAlign),
+ memory_allocation, "aligned phase - alignment initial allocation failed!");
+ }
+ { /* Align the start of the tables to 64 bytes. Use [0, 63] bytes */
+ void* const alloc = ws->objectEnd;
+ size_t const bytesToAlign = ZSTD_cwksp_bytes_to_align_ptr(alloc, ZSTD_CWKSP_ALIGNMENT_BYTES);
+ void* const end = (BYTE*)alloc + bytesToAlign;
+ DEBUGLOG(5, "reserving table alignment addtl space: %zu", bytesToAlign);
+ RETURN_ERROR_IF(end > ws->workspaceEnd, memory_allocation,
+ "table phase - alignment initial allocation failed!");
+ ws->objectEnd = end;
+ ws->tableEnd = end;
+ ws->tableValidEnd = end;
}
}
ws->phase = phase;
+ ZSTD_cwksp_assert_internal_consistency(ws);
}
+ return 0;
}
/**
@@ -224,34 +323,26 @@ MEM_STATIC int ZSTD_cwksp_owns_buffer(const ZSTD_cwksp* ws, const void* ptr) {
MEM_STATIC void* ZSTD_cwksp_reserve_internal(
ZSTD_cwksp* ws, size_t bytes, ZSTD_cwksp_alloc_phase_e phase) {
void* alloc;
- void* bottom = ws->tableEnd;
- ZSTD_cwksp_internal_advance_phase(ws, phase);
- alloc = (BYTE *)ws->allocStart - bytes;
+ if (ZSTD_isError(ZSTD_cwksp_internal_advance_phase(ws, phase)) || bytes == 0) {
+ return NULL;
+ }
-#if defined (ADDRESS_SANITIZER) && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
+#if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
/* over-reserve space */
- alloc = (BYTE *)alloc - 2 * ZSTD_CWKSP_ASAN_REDZONE_SIZE;
+ bytes += 2 * ZSTD_CWKSP_ASAN_REDZONE_SIZE;
#endif
- DEBUGLOG(5, "cwksp: reserving %p %zd bytes, %zd bytes remaining",
- alloc, bytes, ZSTD_cwksp_available_space(ws) - bytes);
- ZSTD_cwksp_assert_internal_consistency(ws);
- assert(alloc >= bottom);
- if (alloc < bottom) {
- DEBUGLOG(4, "cwksp: alloc failed!");
- ws->allocFailed = 1;
- return NULL;
- }
- if (alloc < ws->tableValidEnd) {
- ws->tableValidEnd = alloc;
- }
- ws->allocStart = alloc;
+ alloc = ZSTD_cwksp_reserve_internal_buffer_space(ws, bytes);
-#if defined (ADDRESS_SANITIZER) && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
+#if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
/* Move alloc so there's ZSTD_CWKSP_ASAN_REDZONE_SIZE unused space on
* either size. */
- alloc = (BYTE *)alloc + ZSTD_CWKSP_ASAN_REDZONE_SIZE;
- __asan_unpoison_memory_region(alloc, bytes);
+ if (alloc) {
+ alloc = (BYTE *)alloc + ZSTD_CWKSP_ASAN_REDZONE_SIZE;
+ if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) {
+ __asan_unpoison_memory_region(alloc, bytes);
+ }
+ }
#endif
return alloc;
@@ -265,28 +356,36 @@ MEM_STATIC BYTE* ZSTD_cwksp_reserve_buffer(ZSTD_cwksp* ws, size_t bytes) {
}
/**
- * Reserves and returns memory sized on and aligned on sizeof(unsigned).
+ * Reserves and returns memory sized on and aligned on ZSTD_CWKSP_ALIGNMENT_BYTES (64 bytes).
*/
MEM_STATIC void* ZSTD_cwksp_reserve_aligned(ZSTD_cwksp* ws, size_t bytes) {
- assert((bytes & (sizeof(U32)-1)) == 0);
- return ZSTD_cwksp_reserve_internal(ws, ZSTD_cwksp_align(bytes, sizeof(U32)), ZSTD_cwksp_alloc_aligned);
+ void* ptr = ZSTD_cwksp_reserve_internal(ws, ZSTD_cwksp_align(bytes, ZSTD_CWKSP_ALIGNMENT_BYTES),
+ ZSTD_cwksp_alloc_aligned);
+ assert(((size_t)ptr & (ZSTD_CWKSP_ALIGNMENT_BYTES-1))== 0);
+ return ptr;
}
/**
- * Aligned on sizeof(unsigned). These buffers have the special property that
+ * Aligned on 64 bytes. These buffers have the special property that
* their values remain constrained, allowing us to re-use them without
* memset()-ing them.
*/
MEM_STATIC void* ZSTD_cwksp_reserve_table(ZSTD_cwksp* ws, size_t bytes) {
const ZSTD_cwksp_alloc_phase_e phase = ZSTD_cwksp_alloc_aligned;
- void* alloc = ws->tableEnd;
- void* end = (BYTE *)alloc + bytes;
- void* top = ws->allocStart;
+ void* alloc;
+ void* end;
+ void* top;
+
+ if (ZSTD_isError(ZSTD_cwksp_internal_advance_phase(ws, phase))) {
+ return NULL;
+ }
+ alloc = ws->tableEnd;
+ end = (BYTE *)alloc + bytes;
+ top = ws->allocStart;
DEBUGLOG(5, "cwksp: reserving %p table %zd bytes, %zd bytes remaining",
alloc, bytes, ZSTD_cwksp_available_space(ws) - bytes);
assert((bytes & (sizeof(U32)-1)) == 0);
- ZSTD_cwksp_internal_advance_phase(ws, phase);
ZSTD_cwksp_assert_internal_consistency(ws);
assert(end <= top);
if (end > top) {
@@ -296,10 +395,14 @@ MEM_STATIC void* ZSTD_cwksp_reserve_table(ZSTD_cwksp* ws, size_t bytes) {
}
ws->tableEnd = end;
-#if defined (ADDRESS_SANITIZER) && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
- __asan_unpoison_memory_region(alloc, bytes);
+#if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
+ if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) {
+ __asan_unpoison_memory_region(alloc, bytes);
+ }
#endif
+ assert((bytes & (ZSTD_CWKSP_ALIGNMENT_BYTES-1)) == 0);
+ assert(((size_t)alloc & (ZSTD_CWKSP_ALIGNMENT_BYTES-1))== 0);
return alloc;
}
@@ -311,7 +414,7 @@ MEM_STATIC void* ZSTD_cwksp_reserve_object(ZSTD_cwksp* ws, size_t bytes) {
void* alloc = ws->objectEnd;
void* end = (BYTE*)alloc + roundedBytes;
-#if defined (ADDRESS_SANITIZER) && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
+#if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
/* over-reserve space */
end = (BYTE *)end + 2 * ZSTD_CWKSP_ASAN_REDZONE_SIZE;
#endif
@@ -332,11 +435,13 @@ MEM_STATIC void* ZSTD_cwksp_reserve_object(ZSTD_cwksp* ws, size_t bytes) {
ws->tableEnd = end;
ws->tableValidEnd = end;
-#if defined (ADDRESS_SANITIZER) && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
+#if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
/* Move alloc so there's ZSTD_CWKSP_ASAN_REDZONE_SIZE unused space on
* either size. */
alloc = (BYTE *)alloc + ZSTD_CWKSP_ASAN_REDZONE_SIZE;
- __asan_unpoison_memory_region(alloc, bytes);
+ if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) {
+ __asan_unpoison_memory_region(alloc, bytes);
+ }
#endif
return alloc;
@@ -345,7 +450,7 @@ MEM_STATIC void* ZSTD_cwksp_reserve_object(ZSTD_cwksp* ws, size_t bytes) {
MEM_STATIC void ZSTD_cwksp_mark_tables_dirty(ZSTD_cwksp* ws) {
DEBUGLOG(4, "cwksp: ZSTD_cwksp_mark_tables_dirty");
-#if defined (MEMORY_SANITIZER) && !defined (ZSTD_MSAN_DONT_POISON_WORKSPACE)
+#if ZSTD_MEMORY_SANITIZER && !defined (ZSTD_MSAN_DONT_POISON_WORKSPACE)
/* To validate that the table re-use logic is sound, and that we don't
* access table space that we haven't cleaned, we re-"poison" the table
* space every time we mark it dirty. */
@@ -380,7 +485,7 @@ MEM_STATIC void ZSTD_cwksp_clean_tables(ZSTD_cwksp* ws) {
assert(ws->tableValidEnd >= ws->objectEnd);
assert(ws->tableValidEnd <= ws->allocStart);
if (ws->tableValidEnd < ws->tableEnd) {
- memset(ws->tableValidEnd, 0, (BYTE*)ws->tableEnd - (BYTE*)ws->tableValidEnd);
+ ZSTD_memset(ws->tableValidEnd, 0, (BYTE*)ws->tableEnd - (BYTE*)ws->tableValidEnd);
}
ZSTD_cwksp_mark_tables_clean(ws);
}
@@ -392,8 +497,12 @@ MEM_STATIC void ZSTD_cwksp_clean_tables(ZSTD_cwksp* ws) {
MEM_STATIC void ZSTD_cwksp_clear_tables(ZSTD_cwksp* ws) {
DEBUGLOG(4, "cwksp: clearing tables!");
-#if defined (ADDRESS_SANITIZER) && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
- {
+#if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
+ /* We don't do this when the workspace is statically allocated, because
+ * when that is the case, we have no capability to hook into the end of the
+ * workspace's lifecycle to unpoison the memory.
+ */
+ if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) {
size_t size = (BYTE*)ws->tableValidEnd - (BYTE*)ws->objectEnd;
__asan_poison_memory_region(ws->objectEnd, size);
}
@@ -410,7 +519,7 @@ MEM_STATIC void ZSTD_cwksp_clear_tables(ZSTD_cwksp* ws) {
MEM_STATIC void ZSTD_cwksp_clear(ZSTD_cwksp* ws) {
DEBUGLOG(4, "cwksp: clearing!");
-#if defined (MEMORY_SANITIZER) && !defined (ZSTD_MSAN_DONT_POISON_WORKSPACE)
+#if ZSTD_MEMORY_SANITIZER && !defined (ZSTD_MSAN_DONT_POISON_WORKSPACE)
/* To validate that the context re-use logic is sound, and that we don't
* access stuff that this compression hasn't initialized, we re-"poison"
* the workspace (or at least the non-static, non-table parts of it)
@@ -421,8 +530,12 @@ MEM_STATIC void ZSTD_cwksp_clear(ZSTD_cwksp* ws) {
}
#endif
-#if defined (ADDRESS_SANITIZER) && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
- {
+#if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
+ /* We don't do this when the workspace is statically allocated, because
+ * when that is the case, we have no capability to hook into the end of the
+ * workspace's lifecycle to unpoison the memory.
+ */
+ if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) {
size_t size = (BYTE*)ws->workspaceEnd - (BYTE*)ws->objectEnd;
__asan_poison_memory_region(ws->objectEnd, size);
}
@@ -442,7 +555,7 @@ MEM_STATIC void ZSTD_cwksp_clear(ZSTD_cwksp* ws) {
* Any existing values in the workspace are ignored (the previously managed
* buffer, if present, must be separately freed).
*/
-MEM_STATIC void ZSTD_cwksp_init(ZSTD_cwksp* ws, void* start, size_t size) {
+MEM_STATIC void ZSTD_cwksp_init(ZSTD_cwksp* ws, void* start, size_t size, ZSTD_cwksp_static_alloc_e isStatic) {
DEBUGLOG(4, "cwksp: init'ing workspace with %zd bytes", size);
assert(((size_t)start & (sizeof(void*)-1)) == 0); /* ensure correct alignment */
ws->workspace = start;
@@ -450,39 +563,45 @@ MEM_STATIC void ZSTD_cwksp_init(ZSTD_cwksp* ws, void* start, size_t size) {
ws->objectEnd = ws->workspace;
ws->tableValidEnd = ws->objectEnd;
ws->phase = ZSTD_cwksp_alloc_objects;
+ ws->isStatic = isStatic;
ZSTD_cwksp_clear(ws);
ws->workspaceOversizedDuration = 0;
ZSTD_cwksp_assert_internal_consistency(ws);
}
MEM_STATIC size_t ZSTD_cwksp_create(ZSTD_cwksp* ws, size_t size, ZSTD_customMem customMem) {
- void* workspace = ZSTD_malloc(size, customMem);
+ void* workspace = ZSTD_customMalloc(size, customMem);
DEBUGLOG(4, "cwksp: creating new workspace with %zd bytes", size);
RETURN_ERROR_IF(workspace == NULL, memory_allocation, "NULL pointer!");
- ZSTD_cwksp_init(ws, workspace, size);
+ ZSTD_cwksp_init(ws, workspace, size, ZSTD_cwksp_dynamic_alloc);
return 0;
}
MEM_STATIC void ZSTD_cwksp_free(ZSTD_cwksp* ws, ZSTD_customMem customMem) {
void *ptr = ws->workspace;
DEBUGLOG(4, "cwksp: freeing workspace");
- memset(ws, 0, sizeof(ZSTD_cwksp));
- ZSTD_free(ptr, customMem);
+ ZSTD_memset(ws, 0, sizeof(ZSTD_cwksp));
+ ZSTD_customFree(ptr, customMem);
}
/**
* Moves the management of a workspace from one cwksp to another. The src cwksp
- * is left in an invalid state (src must be re-init()'ed before its used again).
+ * is left in an invalid state (src must be re-init()'ed before it's used again).
*/
MEM_STATIC void ZSTD_cwksp_move(ZSTD_cwksp* dst, ZSTD_cwksp* src) {
*dst = *src;
- memset(src, 0, sizeof(ZSTD_cwksp));
+ ZSTD_memset(src, 0, sizeof(ZSTD_cwksp));
}
MEM_STATIC size_t ZSTD_cwksp_sizeof(const ZSTD_cwksp* ws) {
return (size_t)((BYTE*)ws->workspaceEnd - (BYTE*)ws->workspace);
}
+MEM_STATIC size_t ZSTD_cwksp_used(const ZSTD_cwksp* ws) {
+ return (size_t)((BYTE*)ws->tableEnd - (BYTE*)ws->workspace)
+ + (size_t)((BYTE*)ws->workspaceEnd - (BYTE*)ws->allocStart);
+}
+
MEM_STATIC int ZSTD_cwksp_reserve_failed(const ZSTD_cwksp* ws) {
return ws->allocFailed;
}
@@ -491,6 +610,24 @@ MEM_STATIC int ZSTD_cwksp_reserve_failed(const ZSTD_cwksp* ws) {
* Functions Checking Free Space
***************************************/
+/* ZSTD_alignmentSpaceWithinBounds() :
+ * Returns if the estimated space needed for a wksp is within an acceptable limit of the
+ * actual amount of space used.
+ */
+MEM_STATIC int ZSTD_cwksp_estimated_space_within_bounds(const ZSTD_cwksp* const ws,
+ size_t const estimatedSpace, int resizedWorkspace) {
+ if (resizedWorkspace) {
+ /* Resized/newly allocated wksp should have exact bounds */
+ return ZSTD_cwksp_used(ws) == estimatedSpace;
+ } else {
+ /* Due to alignment, when reusing a workspace, we can actually consume 63 fewer or more bytes
+ * than estimatedSpace. See the comments in zstd_cwksp.h for details.
+ */
+ return (ZSTD_cwksp_used(ws) >= estimatedSpace - 63) && (ZSTD_cwksp_used(ws) <= estimatedSpace + 63);
+ }
+}
+
+
MEM_STATIC size_t ZSTD_cwksp_available_space(ZSTD_cwksp* ws) {
return (size_t)((BYTE*)ws->allocStart - (BYTE*)ws->tableEnd);
}