1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 // This is a simple allocator based on the windows heap. 6 7 extern "C" { 8 9 HANDLE win_heap; 10 11 bool win_heap_init(bool use_lfh) { 12 win_heap = HeapCreate(0, 0, 0); 13 if (win_heap == NULL) 14 return false; 15 16 if (use_lfh) { 17 ULONG enable_lfh = 2; 18 HeapSetInformation(win_heap, HeapCompatibilityInformation, 19 &enable_lfh, sizeof(enable_lfh)); 20 // NOTE: Setting LFH may fail. Vista already has it enabled. 21 // And under the debugger, it won't use LFH. So we 22 // ignore any errors. 23 } 24 25 return true; 26 } 27 28 void* win_heap_malloc(size_t size) { 29 return HeapAlloc(win_heap, 0, size); 30 } 31 32 void win_heap_free(void* size) { 33 HeapFree(win_heap, 0, size); 34 } 35 36 void* win_heap_realloc(void* ptr, size_t size) { 37 if (!ptr) 38 return win_heap_malloc(size); 39 if (!size) { 40 win_heap_free(ptr); 41 return NULL; 42 } 43 return HeapReAlloc(win_heap, 0, ptr, size); 44 } 45 46 size_t win_heap_msize(void* ptr) { 47 return HeapSize(win_heap, 0, ptr); 48 } 49 50 void* win_heap_memalign(size_t alignment, size_t size) { 51 // Reserve enough space to ensure we can align and set aligned_ptr[-1] to the 52 // original allocation for use with win_heap_memalign_free() later. 53 size_t allocation_size = size + (alignment - 1) + sizeof(void*); 54 55 // Check for overflow. Alignment and size are checked in allocator_shim. 56 DCHECK_LT(size, allocation_size); 57 DCHECK_LT(alignment, allocation_size); 58 59 // Since we're directly calling the allocator function, before OOM handling, 60 // we need to NULL check to ensure the allocation succeeded. 61 void* ptr = win_heap_malloc(allocation_size); 62 if (!ptr) 63 return ptr; 64 65 char* aligned_ptr = static_cast<char*>(ptr) + sizeof(void*); 66 aligned_ptr += 67 alignment - reinterpret_cast<uintptr_t>(aligned_ptr) & (alignment - 1); 68 69 reinterpret_cast<void**>(aligned_ptr)[-1] = ptr; 70 return aligned_ptr; 71 } 72 73 void win_heap_memalign_free(void* ptr) { 74 if (ptr) 75 win_heap_free(static_cast<void**>(ptr)[-1]); 76 } 77 78 } // extern "C" 79
