lib/zstd/zstd_common.c

   1 // SPDX-License-Identifier: (GPL-2.0 or BSD-3-Clause-Clear)
   2 /**
   3  * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
   4  * All rights reserved.
   5  */
   6
   7 /*-*************************************
   8 *  Dependencies
   9 ***************************************/
  10 #include "error_private.h"
  11 #include "zstd_internal.h" /* declaration of ZSTD_isError, ZSTD_getErrorName, ZSTD_getErrorCode, ZSTD_getErrorString, ZSTD_versionNumber */
  12 #include <malloc.h>
  13 #include <linux/kernel.h>
  14
  15 /*=**************************************************************
  16 *  Custom allocator
  17 ****************************************************************/
  18
  19 #define stack_push(stack, size)                                 \
  20         ({                                                      \
  21                 void *const ptr = ZSTD_PTR_ALIGN((stack)->ptr); \
  22                 (stack)->ptr = (char *)ptr + (size);            \
  23                 (stack)->ptr <= (stack)->end ? ptr : NULL;      \
  24         })
  25
  26 ZSTD_customMem ZSTD_initStack(void *workspace, size_t workspaceSize)
  27 {
  28         ZSTD_customMem stackMem = {ZSTD_stackAlloc, ZSTD_stackFree, workspace};
  29         ZSTD_stack *stack = (ZSTD_stack *)workspace;
  30         /* Verify preconditions */
  31         if (!workspace || workspaceSize < sizeof(ZSTD_stack) || workspace != ZSTD_PTR_ALIGN(workspace)) {
  32                 ZSTD_customMem error = {NULL, NULL, NULL};
  33                 return error;
  34         }
  35         /* Initialize the stack */
  36         stack->ptr = workspace;
  37         stack->end = (char *)workspace + workspaceSize;
  38         stack_push(stack, sizeof(ZSTD_stack));
  39         return stackMem;
  40 }
  41
  42 void *ZSTD_stackAllocAll(void *opaque, size_t *size)
  43 {
  44         ZSTD_stack *stack = (ZSTD_stack *)opaque;
  45         *size = (BYTE const *)stack->end - (BYTE *)ZSTD_PTR_ALIGN(stack->ptr);
  46         return stack_push(stack, *size);
  47 }
  48
  49 void *ZSTD_stackAlloc(void *opaque, size_t size)
  50 {
  51         ZSTD_stack *stack = (ZSTD_stack *)opaque;
  52         return stack_push(stack, size);
  53 }
  54 void ZSTD_stackFree(void *opaque, void *address)
  55 {
  56         (void)opaque;
  57         (void)address;
  58 }
  59
  60 void *ZSTD_malloc(size_t size, ZSTD_customMem customMem) { return customMem.customAlloc(customMem.opaque, size); }
  61
  62 void ZSTD_free(void *ptr, ZSTD_customMem customMem)
  63 {
  64         if (ptr != NULL)
  65                 customMem.customFree(customMem.opaque, ptr);
  66 }