1 /* 2 * Copyright 2011, 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 MEM_CHUNK_H 18 #define MEM_CHUNK_H 19 20 #include <stddef.h> 21 #include <stdint.h> 22 #include <stdlib.h> 23 24 typedef void *(*AllocFunc) (size_t, uint32_t); 25 typedef void (*FreeFunc) (void *); 26 27 class MemChunk { 28 private: 29 unsigned char *buf; 30 size_t buf_size; 31 bool bVendorBuf; 32 33 static AllocFunc VendorAlloc; 34 static FreeFunc VendorFree; 35 36 bool invalidBuf() const; 37 38 public: 39 MemChunk(); 40 41 ~MemChunk(); 42 43 bool allocate(size_t size); 44 45 void print() const; 46 47 bool protect(int prot); 48 getBuffer()49 unsigned char const *getBuffer() const { 50 return buf; 51 } 52 getBuffer()53 unsigned char *getBuffer() { 54 return buf; 55 } 56 57 unsigned char &operator[](size_t index) { 58 return buf[index]; 59 } 60 61 unsigned char const &operator[](size_t index) const { 62 return buf[index]; 63 } 64 size()65 size_t size() const { 66 return buf_size; 67 } 68 69 // The allocation function must return page-aligned memory or we will be 70 // unable to mprotect the region appropriately. registerAllocFreeCallbacks(AllocFunc a,FreeFunc f)71 static void registerAllocFreeCallbacks(AllocFunc a, FreeFunc f) { 72 VendorAlloc = a; 73 VendorFree = f; 74 } 75 }; 76 77 #endif // MEM_CHUNK_H 78