1 /* Debug allocators for the Expat test suite 2 __ __ _ 3 ___\ \/ /_ __ __ _| |_ 4 / _ \\ /| '_ \ / _` | __| 5 | __// \| |_) | (_| | |_ 6 \___/_/\_\ .__/ \__,_|\__| 7 |_| XML parser 8 9 Copyright (c) 1997-2000 Thai Open Source Software Center Ltd 10 Copyright (c) 2000-2017 Expat development team 11 Licensed under the MIT license: 12 13 Permission is hereby granted, free of charge, to any person obtaining 14 a copy of this software and associated documentation files (the 15 "Software"), to deal in the Software without restriction, including 16 without limitation the rights to use, copy, modify, merge, publish, 17 distribute, sublicense, and/or sell copies of the Software, and to permit 18 persons to whom the Software is furnished to do so, subject to the 19 following conditions: 20 21 The above copyright notice and this permission notice shall be included 22 in all copies or substantial portions of the Software. 23 24 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 25 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 26 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN 27 NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 28 DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 29 OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 30 USE OR OTHER DEALINGS IN THE SOFTWARE. 31 */ 32 33 #include <stdio.h> 34 #include <stdlib.h> 35 #include "memcheck.h" 36 37 38 /* Structures to keep track of what has been allocated. Speed isn't a 39 * big issue for the tests this is required for, so we will use a 40 * doubly-linked list to make deletion easier. 41 */ 42 43 typedef struct allocation_entry { 44 struct allocation_entry * next; 45 struct allocation_entry * prev; 46 void * allocation; 47 size_t num_bytes; 48 } AllocationEntry; 49 50 static AllocationEntry *alloc_head = NULL; 51 static AllocationEntry *alloc_tail = NULL; 52 53 static AllocationEntry *find_allocation(void *ptr); 54 55 56 /* Allocate some memory and keep track of it. */ 57 void * 58 tracking_malloc(size_t size) 59 { 60 AllocationEntry *entry = malloc(sizeof(AllocationEntry)); 61 62 if (entry == NULL) { 63 printf("Allocator failure\n"); 64 return NULL; 65 } 66 entry->num_bytes = size; 67 entry->allocation = malloc(size); 68 if (entry->allocation == NULL) { 69 free(entry); 70 return NULL; 71 } 72 entry->next = NULL; 73 74 /* Add to the list of allocations */ 75 if (alloc_head == NULL) { 76 entry->prev = NULL; 77 alloc_head = alloc_tail = entry; 78 } else { 79 entry->prev = alloc_tail; 80 alloc_tail->next = entry; 81 alloc_tail = entry; 82 } 83 84 return entry->allocation; 85 } 86 87 static AllocationEntry * 88 find_allocation(void *ptr) 89 { 90 AllocationEntry *entry; 91 92 for (entry = alloc_head; entry != NULL; entry = entry->next) { 93 if (entry->allocation == ptr) { 94 return entry; 95 } 96 } 97 return NULL; 98 } 99 100 /* Free some memory and remove the tracking for it */ 101 void 102 tracking_free(void *ptr) 103 { 104 AllocationEntry *entry; 105 106 if (ptr == NULL) { 107 /* There won't be an entry for this */ 108 return; 109 } 110 111 entry = find_allocation(ptr); 112 if (entry != NULL) { 113 /* This is the relevant allocation. Unlink it */ 114 if (entry->prev != NULL) 115 entry->prev->next = entry->next; 116 else 117 alloc_head = entry->next; 118 if (entry->next != NULL) 119 entry->next->prev = entry->prev; 120 else 121 alloc_tail = entry->next; 122 free(entry); 123 } else { 124 printf("Attempting to free unallocated memory at %p\n", ptr); 125 } 126 free(ptr); 127 } 128 129 /* Reallocate some memory and keep track of it */ 130 void * 131 tracking_realloc(void *ptr, size_t size) 132 { 133 AllocationEntry *entry; 134 135 if (ptr == NULL) { 136 /* By definition, this is equivalent to malloc(size) */ 137 return tracking_malloc(size); 138 } 139 if (size == 0) { 140 /* By definition, this is equivalent to free(ptr) */ 141 tracking_free(ptr); 142 return NULL; 143 } 144 145 /* Find the allocation entry for this memory */ 146 entry = find_allocation(ptr); 147 if (entry == NULL) { 148 printf("Attempting to realloc unallocated memory at %p\n", ptr); 149 entry = malloc(sizeof(AllocationEntry)); 150 if (entry == NULL) { 151 printf("Reallocator failure\n"); 152 return NULL; 153 } 154 entry->allocation = realloc(ptr, size); 155 if (entry->allocation == NULL) { 156 free(entry); 157 return NULL; 158 } 159 160 /* Add to the list of allocations */ 161 entry->next = NULL; 162 if (alloc_head == NULL) { 163 entry->prev = NULL; 164 alloc_head = alloc_tail = entry; 165 } else { 166 entry->prev = alloc_tail; 167 alloc_tail->next = entry; 168 alloc_tail = entry; 169 } 170 } else { 171 entry->allocation = realloc(ptr, size); 172 if (entry->allocation == NULL) { 173 /* Realloc semantics say the original is still allocated */ 174 entry->allocation = ptr; 175 return NULL; 176 } 177 } 178 179 entry->num_bytes = size; 180 return entry->allocation; 181 } 182 183 int 184 tracking_report(void) 185 { 186 AllocationEntry *entry; 187 188 if (alloc_head == NULL) 189 return 1; 190 191 /* Otherwise we have allocations that haven't been freed */ 192 for (entry = alloc_head; entry != NULL; entry = entry->next) 193 { 194 printf("Allocated %lu bytes at %p\n", 195 (long unsigned)entry->num_bytes, entry->allocation); 196 } 197 return 0; 198 } 199
