Fixed dlists.

Also added tests.

src/dlist.c

@@ -21,9 +21,9 @@ void dlist_destroy(DList* dlist) {
 
 void dlist_destroypsv(DList* dlist) { free(dlist); }
 
-// Check whether the buffer is overflowing and resize it if necessary.
-void dlist_check_resz(DList* dlist, size_t ln) {
-    while (dlist->ln + ln + 1 > dlist->sz) {
+// Check whether the buffer is about to overflow and resize it if necessary.
+void dlist_check_resz(DList* dlist) {
+    while ((dlist->ln + 1) * sizeof(void*) >= dlist->sz) {
         // Double the buffer size when overflown.
         dlist->sz *= 2;
         dlist->buf = realloc(dlist->buf, dlist->sz);
@@ -34,8 +34,8 @@ void dlist_check_resz(DList* dlist, size_t ln) {
 }
 
 void dlist_append(DList* dest, void* src) {
-    dlist_check_resz(dest, 1);
+    dlist_check_resz(dest);
 
     dest->buf[dest->ln] = src;
-    dest->ln += 1;
+    dest->ln++;
 }

src/include/dlist.h

@@ -3,7 +3,7 @@
 
 #include <stdlib.h>
 
-#define DLIST_INITSZ 128
+#define DLIST_INITSZ 128 * sizeof(void*)
 
 typedef struct {
     void** buf; // The buffer containing the list.

test/test_dlist.c

@@ -0,0 +1,41 @@
+#include "../src/include/dlist.h"
+#include "Unity/src/unity.h"
+
+void setUp() {};
+void tearDown() {};
+
+void test_dlist_init() {
+    DList* dlist = dlist_init();
+    TEST_ASSERT_EQUAL(0, dlist->ln);
+    TEST_ASSERT_EQUAL(DLIST_INITSZ, dlist->sz);
+}
+
+void test_dlist_append() {
+    DList* dlist;
+
+    // Test simple appending.
+    dlist = dlist_init();
+    int* n = malloc(sizeof(int));
+    *n = 1;
+    dlist_append(dlist, n);
+
+    TEST_ASSERT_EQUAL(n, dlist->buf[0]);
+    TEST_ASSERT_EQUAL(1, dlist->ln);
+
+    dlist_destroy(dlist);
+
+    // Test buffer doubling.
+    dlist = dlist_init();
+
+    for (int i = 0; i < 129; i++) dlist_append(dlist, &i);
+
+    TEST_ASSERT_EQUAL(129, dlist->ln);
+    TEST_ASSERT_EQUAL(DLIST_INITSZ*2, dlist->sz);
+}
+
+int main() {
+    UNITY_BEGIN();
+    RUN_TEST(test_dlist_init);
+    RUN_TEST(test_dlist_append);
+    return UNITY_END();
+}