Add random access interface to list.

src/basic/container/list.c

@@ -70,3 +70,17 @@ void* listPop(List *l) {
 
     return v;
 }
+
+void* listGet(List *l, int idx) {
+
+    int i = 0;
+
+    if (listEmpty(l))
+        return NULL;
+
+    Node *current = listHead(l);
+    while (current && ++i <= idx)
+        current = nodeNext(current);
+
+    return current->val;
+}

src/basic/container/list.h

@@ -44,6 +44,7 @@ List* createList(void);
 void  destroyList(List **l);
 void  listPush(List *l, void *val);
 void* listPop(List *l);
+void* listGet(List *l, int idx);
 
 
 

tests/listTestCases.c

@@ -81,3 +81,28 @@ CTEST2(LIST_TEST, POP_FROM_EMPTY_LIST) {
 
     LIST_EMPTY_STATUS_CHECK(data->l);
 }
+
+CTEST2(LIST_TEST, RANDOM_ACCESS) {
+    int *val = NULL;
+
+    for (int i = 0; i < 1000; ++i) {
+        val = (int*)malloc(sizeof(int));
+        *val = i;
+        listPush(data->l, val);
+    }
+
+
+    for (int i = 0; i < 1000; ++i) {
+        val = listGet(data->l, i);
+        printf("%d\n", *(int*)val);
+        ASSERT_EQUAL(*(int*)val, i);
+    }
+}
+
+CTEST2(LIST_TEST, RANDOM_ACCESS_EMPTY) {
+    int *val = NULL;
+    for (int i = 0; i < 256; ++i) {
+        val = listGet(data->l, i);
+        ASSERT_NULL(val);
+    }
+}