| 1 | /** |
| 2 | * @file Stack.c |
| 3 | */ |
| 4 | |
| 5 | #include "cgds/Stack.h" |
| 6 | |
| 7 | void _stack_init(Stack* stack, size_t dataSize) |
| 8 | { |
| 9 | stack->size = 0; |
| 10 | stack->dataSize = dataSize; |
| 11 | stack->top = NULL; |
| 12 | } |
| 13 | |
| 14 | Stack* _stack_new(size_t dataSize) |
| 15 | { |
| 16 | Stack* stack = (Stack*) safe_malloc(sizeof (Stack)); |
| 17 | _stack_init(stack, dataSize); |
| 18 | return stack; |
| 19 | } |
| 20 | |
| 21 | Stack* stack_copy(Stack* stack) |
| 22 | { |
| 23 | // since a stack is a single-linked list, an auxiliary storage is required |
| 24 | void** tmpStorage = (void**) malloc(stack->size * sizeof (void*)); |
| 25 | StackCell* stackCell = stack->top; |
| 26 | for (UInt i = 0; i < stack->size; i++) |
| 27 | { |
| 28 | tmpStorage[stack->size - 1 - i] = stackCell->data; |
| 29 | stackCell = stackCell->previous; |
| 30 | } |
| 31 | // now transfer tmpStorage contents (pushed in right order) in a new stack |
| 32 | Stack* stackCopy = _stack_new(stack->dataSize); |
| 33 | for (UInt i = 0; i < stack->size; i++) |
| 34 | _stack_push(stackCopy, tmpStorage[i]); |
| 35 | free(tmpStorage); |
| 36 | return stackCopy; |
| 37 | } |
| 38 | |
| 39 | Bool stack_empty(Stack* stack) |
| 40 | { |
| 41 | return (stack->size == 0); |
| 42 | } |
| 43 | |
| 44 | UInt stack_size(Stack* stack) |
| 45 | { |
| 46 | return stack->size; |
| 47 | } |
| 48 | |
| 49 | void _stack_push(Stack* stack, void* data) |
| 50 | { |
| 51 | StackCell* newStackTop = (StackCell*) safe_malloc(sizeof (StackCell)); |
| 52 | newStackTop->data = safe_malloc(stack->dataSize); |
| 53 | memcpy(newStackTop->data, data, stack->dataSize); |
| 54 | newStackTop->previous = stack->top; |
| 55 | stack->top = newStackTop; |
| 56 | stack->size++; |
| 57 | } |
| 58 | |
| 59 | void* _stack_top(Stack* stack) |
| 60 | { |
| 61 | return stack->top->data; |
| 62 | } |
| 63 | |
| 64 | void stack_pop(Stack* stack) |
| 65 | { |
| 66 | StackCell* toTrash = stack->top; |
| 67 | stack->top = stack->top->previous; |
| 68 | safe_free(toTrash->data); |
| 69 | safe_free(toTrash); |
| 70 | stack->size--; |
| 71 | } |
| 72 | |
| 73 | void stack_clear(Stack* stack) |
| 74 | { |
| 75 | while (stack->size > 0) |
| 76 | stack_pop(stack); |
| 77 | _stack_init(stack, stack->dataSize); |
| 78 | } |
| 79 | |
| 80 | void stack_destroy(Stack* stack) |
| 81 | { |
| 82 | stack_clear(stack); |
| 83 | safe_free(stack); |
| 84 | } |