1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef bbs_DYN_MEM_MANAGER_EM_H 18 #define bbs_DYN_MEM_MANAGER_EM_H 19 20 /* ---- includes ----------------------------------------------------------- */ 21 22 #include "b_BasicEm/Basic.h" 23 24 /* ---- related objects --------------------------------------------------- */ 25 26 struct bbs_Context; 27 struct bbs_MemSeg; 28 29 /* ---- typedefs ----------------------------------------------------------- */ 30 31 /** 'malloc' function pointer. 32 * Allocated memory block must be 32-bit-aligned. 33 * sizeA refers to the size of a memory block in bytes 34 */ 35 typedef void* ( *bbs_mallocFPtr )( struct bbs_Context* cpA, 36 const struct bbs_MemSeg* memSegPtrA, 37 uint32 sizeA ); 38 39 /** free function pointer */ 40 typedef void ( *bbs_freeFPtr )( void* memPtrA ); 41 42 /* ---- constants ---------------------------------------------------------- */ 43 44 /* ---- object definition -------------------------------------------------- */ 45 46 /** Dynamic memory manager. 47 * Handles allocation and deallocation of memory blocks via function pointers 48 * to malloc and free. 49 * 50 * Each memory block is organized as follows: 51 * - The first 8 bytes are reserved for the pointer to the next 52 * memory block (8 to allow support of 64-bit platforms). 53 * - Next a 32-bit value stores the allocated memory size in 16-bit units. 54 * - Finally the actual allocated memory area. 55 * This means for each new memory block an additional 12 bytes are allocated. 56 */ 57 struct bbs_DynMemManager 58 { 59 60 /* ---- private data --------------------------------------------------- */ 61 62 /* ---- public data ---------------------------------------------------- */ 63 64 /** pointer to first memory block */ 65 uint16* memPtrE; 66 67 /** function pointer to external mem alloc function (s. comment of type declaration)*/ 68 bbs_mallocFPtr mallocFPtrE; 69 70 /** function pointer to external mem free function */ 71 bbs_freeFPtr freeFPtrE; 72 }; 73 74 /* ---- associated objects ------------------------------------------------- */ 75 76 /* ---- external functions ------------------------------------------------- */ 77 78 /* ---- \ghd{ constructor/destructor } ------------------------------------- */ 79 80 /** initializes bbs_DynMemManager */ 81 void bbs_DynMemManager_init( struct bbs_Context* cpA, struct bbs_DynMemManager* ptrA ); 82 83 /** frees bbs_DynMemManager */ 84 void bbs_DynMemManager_exit( struct bbs_Context* cpA, struct bbs_DynMemManager* ptrA ); 85 86 /* ---- \ghd{ operators } -------------------------------------------------- */ 87 88 /* ---- \ghd{ query functions } -------------------------------------------- */ 89 90 /** returns size of currently allocated memory in 16bit units */ 91 uint32 bbs_DynMemManager_allocatedSize( struct bbs_Context* cpA, const struct bbs_DynMemManager* ptrA ); 92 93 /* ---- \ghd{ modify functions } ------------------------------------------- */ 94 95 /* ---- \ghd{ memory I/O } ------------------------------------------------- */ 96 97 /* ---- \ghd{ exec functions } --------------------------------------------- */ 98 99 /** allocates sizeA words of memory */ 100 uint16* bbs_DynMemManager_alloc( struct bbs_Context* cpA, 101 struct bbs_DynMemManager* ptrA, 102 const struct bbs_MemSeg* memSegPtrA, 103 uint32 sizeA ); 104 105 /** frees previously allocated memory */ 106 void bbs_DynMemManager_free( struct bbs_Context* cpA, 107 struct bbs_DynMemManager* ptrA, 108 uint16* memPtrA ); 109 110 /** returns the next memory block of at least minSizeA length; allocates new block if neccessary */ 111 uint16* bbs_DynMemManager_nextBlock( struct bbs_Context* cpA, 112 struct bbs_DynMemManager* ptrA, 113 const struct bbs_MemSeg* memSegPtrA, 114 uint16* curBlockPtrA, 115 uint32 minSizeA, 116 uint32* actualSizePtrA ); 117 118 /** frees all allocated memory */ 119 void bbs_DynMemManager_freeAll( struct bbs_Context* cpA, 120 struct bbs_DynMemManager* ptrA ); 121 122 123 #endif /* bbs_DYN_MEM_MANAGER_EM_H */ 124 125
