update clang stack

Author: nange

c/stack/stack.c

@@ -0,0 +1,71 @@
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <stdbool.h>
+#include "stack.h"
+
+#define DEFAULT_STACK_SIZE 4
+
+/**
+ * create a new empty stack
+ */
+Stack *stackCreate() {
+  Stack *stack = malloc(sizeof(Stack));
+  assert(stack);
+  stack->top = 0;
+  stack->capacity = DEFAULT_STACK_SIZE;
+  stack->dataStore = malloc(sizeof(void *)*DEFAULT_STACK_SIZE);
+
+  stack->size = stackSize;
+  stack->isEmpty = stackIsEmpty;
+  stack->push = stackPush;
+  stack->pop = stackPop;
+  stack->peek = stackPeek;
+  stack->clear = stackClear;
+  stack->destory = stackDestory;
+}
+
+void stackShouldRealloc(Stack *s) {
+  if (s->top == s->capacity) {
+    s->capacity = s->capacity*2;
+    s->dataStore = realloc(s->dataStore, sizeof(void *)*s->capacity);
+  }
+}
+
+int stackSize(Stack *s) {
+  return s->top;
+}
+
+bool stackIsEmpty(Stack *s) {
+  return s->top == 0;
+}
+
+void stackPush(Stack *s, void *element) {
+  stackShouldRealloc(s);
+  s->dataStore[s->top++] = element;
+}
+
+void *stackPop(Stack *s) {
+  if (s->isEmpty(s)) {
+    return NULL;
+  }
+
+  return s->dataStore[--s->top];
+}
+
+void *stackPeek(Stack *s) {
+  if (s->isEmpty(s)) {
+    return NULL;
+  }
+
+  return s->dataStore[s->top-1];
+}
+
+void stackClear(Stack *s) {
+    s->top = 0;
+}
+
+void stackDestory(Stack *s) {
+  free(s->dataStore);
+  free(s);
+}

c/stack/stack.h

@@ -0,0 +1,28 @@
+#ifndef __STACK_H__
+#define __STACK_H__
+
+typedef struct Stack {
+  int top;
+  int capacity;
+  void **dataStore;
+
+  int (*size)();
+  bool (*isEmpty)();
+  void (*push)();
+  void *(*pop)();
+  void *(*peek)();
+  void (*clear)();
+  void (*destory)();
+} Stack;
+
+/* Prototypes */
+Stack *stackCreate();
+int stackSize(Stack *s);
+bool stackIsEmpty(Stack *s);
+void stackPush(Stack *s, void *);
+void *stackPop(Stack *s);
+void *stackPeek(Stack *s);
+void stackClear(Stack *s);
+void stackDestory(Stack *s);
+
+#endif /* __STACK_H__ */

c/stack/stack_test.c

@@ -0,0 +1,32 @@
+#include <assert.h>
+#include <stdio.h>
+#include "stack.c"
+
+int main() {
+  printf("\nRunning stack.c tests.\n\n");
+
+  Stack *s = stackCreate();
+  assert(s->isEmpty(s));
+  assert(s->size(s) == 0);
+
+  char *c1 = "12";
+  char *c2 = "23";
+  char *c3 = "34";
+  s->push(s, c1);
+  s->push(s, c2);
+  s->push(s, c3);
+  assert(s->size(s) == 3);
+
+  char *c4 = "34";
+  assert(strcmp(c4, (char *)s->pop(s)) == 0);
+  char *c5 = "23";
+  assert(strcmp(c5, (char *)s->peek(s)) == 0);
+
+  s->clear(s);
+  assert(s->isEmpty(s));
+
+  s->destory(s);
+
+  printf("All stack.c tests completed.\n\n");
+  return 0;
+}