1 files changed, 39 insertions, 0 deletions
diff --git a/src/util/darray.c b/src/util/darray.c
new file mode 100644
index 0000000..f117ccf
--- /dev/null
+++ b/src/util/darray.c
@@ -0,0 +1,39 @@
+#include "assert.h"
+#include "darray.h"
+
+
+int darray_size(void *darray) {
+	return darray != NULL ? DARRAY_OCCUPIED(darray) : 0;
+}
+
+void darray_free(void *darray) {
+	if (darray != NULL) {
+		free(DARRAY_RAW_DATA(darray));
+	}
+}
+
+void *darray_hold(void *darray, int count, int itemsize) {
+	assert(count > 0 && itemsize > 0);
+	if (darray == NULL) {
+		int raw_size = sizeof(int) * 2 + itemsize * count;
+		int *base = (int*)malloc(raw_size);
+		base[0] = count;  /* capacity */
+		base[1] = count;  /* occupied */
+		return base + 2;
+	}
+	else if (DARRAY_OCCUPIED(darray) + count <= DARRAY_CAPACITY(darray)) {
+		DARRAY_OCCUPIED(darray) += count;
+		return darray;
+	}
+	else {
+		int needed_size = DARRAY_OCCUPIED(darray) + count;
+		int double_curr = DARRAY_CAPACITY(darray) * 2;
+		int capacity = needed_size > double_curr ? needed_size : double_curr;
+		int occupied = needed_size;
+		int raw_size = sizeof(int) * 2 + itemsize * capacity;
+		int *base = (int*)realloc(DARRAY_RAW_DATA(darray), raw_size);
+		base[0] = capacity;
+		base[1] = occupied;
+		return base + 2;
+	}
+}