source/blender/blenlib/BLI_mmap.h

   1 /* SPDX-FileCopyrightText: 2020 Blender Authors
   2  *
   3  * SPDX-License-Identifier: GPL-2.0-or-later */
   4
   5 #pragma once
   6
   7 /** \file
   8  * \ingroup bli
   9  */
  10
  11 #include "BLI_compiler_attrs.h"
  12 #include "BLI_utildefines.h"
  13
  14 #ifdef __cplusplus
  15 extern "C" {
  16 #endif
  17
  18 /* Memory-mapped file IO that implements all the OS-specific details and error handling. */
  19
  20 struct BLI_mmap_file;
  21
  22 typedef struct BLI_mmap_file BLI_mmap_file;
  23
  24 /* Prepares an opened file for memory-mapped IO.
  25  * May return NULL if the operation fails.
  26  * Note that this seeks to the end of the file to determine its length. */
  27 BLI_mmap_file *BLI_mmap_open(int fd) ATTR_MALLOC ATTR_WARN_UNUSED_RESULT;
  28
  29 /* Reads length bytes from file at the given offset into dest.
  30  * Returns whether the operation was successful (may fail when reading beyond the file
  31  * end or when IO errors occur). */
  32 bool BLI_mmap_read(BLI_mmap_file *file, void *dest, size_t offset, size_t length)
  33     ATTR_WARN_UNUSED_RESULT ATTR_NONNULL(1);
  34
  35 void *BLI_mmap_get_pointer(BLI_mmap_file *file) ATTR_WARN_UNUSED_RESULT;
  36 size_t BLI_mmap_get_length(const BLI_mmap_file *file) ATTR_WARN_UNUSED_RESULT;
  37
  38 void BLI_mmap_free(BLI_mmap_file *file) ATTR_NONNULL(1);
  39
  40 #ifdef __cplusplus
  41 }
  42 #endif