1 // Copyright 2014 PDFium 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 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6 
7 #ifndef CORE_INCLUDE_FXCRT_FX_MEMORY_H_
8 #define CORE_INCLUDE_FXCRT_FX_MEMORY_H_
9 
10 #include "fx_system.h"
11 
12 #ifdef __cplusplus
13 extern "C" {
14 #endif
15 // For external C libraries to malloc through PDFium. These may return NULL.
16 void*	FXMEM_DefaultAlloc(size_t byte_size, int flags);
17 void*	FXMEM_DefaultRealloc(void* pointer, size_t new_size, int flags);
18 void	FXMEM_DefaultFree(void* pointer, int flags);
19 #ifdef __cplusplus
20 }  // extern "C"
21 
22 #include <stdlib.h>
23 #include <limits>
24 #include <new>
25 
26 NEVER_INLINE void FX_OutOfMemoryTerminate();
27 
FX_SafeRealloc(void * ptr,size_t num_members,size_t member_size)28 inline void* FX_SafeRealloc(void* ptr, size_t num_members, size_t member_size) {
29     if (num_members < std::numeric_limits<size_t>::max() / member_size) {
30         return realloc(ptr, num_members * member_size);
31     }
32     return nullptr;
33 }
34 
FX_AllocOrDie(size_t num_members,size_t member_size)35 inline void* FX_AllocOrDie(size_t num_members, size_t member_size) {
36     // TODO(tsepez): See if we can avoid the implicit memset(0).
37     if (void* result = calloc(num_members, member_size)) {
38         return result;
39     }
40     FX_OutOfMemoryTerminate();  // Never returns.
41     return nullptr;  // Suppress compiler warning.
42 }
43 
FX_AllocOrDie2D(size_t w,size_t h,size_t member_size)44 inline void* FX_AllocOrDie2D(size_t w, size_t h, size_t member_size) {
45     if (w < std::numeric_limits<size_t>::max() / h) {
46         return FX_AllocOrDie(w * h, member_size);
47     }
48     FX_OutOfMemoryTerminate();  // Never returns.
49     return nullptr;  // Suppress compiler warning.
50 }
51 
FX_ReallocOrDie(void * ptr,size_t num_members,size_t member_size)52 inline void* FX_ReallocOrDie(void* ptr, size_t num_members, size_t member_size) {
53     if (void* result = FX_SafeRealloc(ptr, num_members, member_size)) {
54         return result;
55     }
56     FX_OutOfMemoryTerminate();  // Never returns.
57     return nullptr;  // Suppress compiler warning.
58 }
59 
60 // Never returns NULL.
61 #define FX_Alloc(type, size) (type*)FX_AllocOrDie(size, sizeof(type))
62 #define FX_Alloc2D(type, w, h) (type*)FX_AllocOrDie2D(w, h, sizeof(type))
63 #define FX_Realloc(type, ptr, size) \
64     (type*)FX_ReallocOrDie(ptr, size, sizeof(type))
65 
66 // May return NULL.
67 #define FX_TryAlloc(type, size) (type*)calloc(size, sizeof(type))
68 #define FX_TryRealloc(type, ptr, size) \
69     (type*)FX_SafeRealloc(ptr, size, sizeof(type))
70 
71 #define FX_Free(ptr) free(ptr)
72 
73 class CFX_DestructObject
74 {
75 public:
76 
~CFX_DestructObject()77     virtual ~CFX_DestructObject() {}
78 };
79 class CFX_GrowOnlyPool
80 {
81 public:
82 
83     CFX_GrowOnlyPool(size_t trunk_size = 16384);
84 
85     ~CFX_GrowOnlyPool();
86 
SetTrunkSize(size_t trunk_size)87     void	SetTrunkSize(size_t trunk_size)
88     {
89         m_TrunkSize = trunk_size;
90     }
91 
AllocDebug(size_t size,FX_LPCSTR file,int line)92     void*	AllocDebug(size_t size, FX_LPCSTR file, int line)
93     {
94         return Alloc(size);
95     }
96 
97     void*	Alloc(size_t size);
98 
ReallocDebug(void * p,size_t new_size,FX_LPCSTR file,int line)99     void*	ReallocDebug(void* p, size_t new_size, FX_LPCSTR file, int line)
100     {
101         return NULL;
102     }
103 
Realloc(void * p,size_t new_size)104     void*	Realloc(void* p, size_t new_size)
105     {
106         return NULL;
107     }
108 
Free(void *)109     void	Free(void*) {}
110 
111     void	FreeAll();
112 private:
113 
114     size_t	m_TrunkSize;
115 
116     void*	m_pFirstTrunk;
117 };
118 #endif  // __cplusplus
119 
120 #endif  // CORE_INCLUDE_FXCRT_FX_MEMORY_H_
121