bitmap: implement bitmap_set_range, bitmap_get and bitmap_destroy

kernel-src/lib/bitmap.c

@@ -4,22 +4,58 @@
 #include <util.h>
 #include <logging.h>
 
+#define BYTE_INDEX(idx) ((idx) / (sizeof(long) * 8))
+#define BIT_INDEX(idx) ((idx) % (sizeof(long) * 8))
+
 int bitmap_init(bitmap_t *bitmap, size_t size) {
 	bitmap->data = alloc(size);
 	bitmap->size = size;
 
+	if (bitmap->data != NULL)
+		memset(bitmap->data, 0, size);
+
 	return bitmap->data ? 0 : ENOMEM;
 }
 
-void bitmap_set(bitmap_t *bitmap, long idx, int v) {
-	__assert(bitmap->size > idx);
+void bitmap_destroy(bitmap_t *bitmap) {
+	free(bitmap->data);
+	bitmap->data = NULL;
+	bitmap->size = 0;
+}
 
-	long bit = 1llu << (idx % sizeof(*bitmap->data));
+void bitmap_set(bitmap_t *bitmap, long idx, int v) {
+	__assert(idx < bitmap->size);
+
+	long *ptr = &bitmap->data[BYTE_INDEX(idx)];
+	long bit = 1lu << BIT_INDEX(idx);
 
 	if (v)
-		bitmap->data[idx / sizeof(*bitmap->data)] |= bit;
+		*ptr |= bit;
 	else
-		bitmap->data[idx / sizeof(*bitmap->data)] &= ~bit;
+		*ptr &= ~bit;
+}
+
+void bitmap_set_range(bitmap_t *bitmap, long start, long count, int v) {
+	__assert(start + count <= bitmap->size);
+
+	for (long i = 0; i < count; ++i) {
+		long idx = start + i;
+
+		long *ptr = &bitmap->data[BYTE_INDEX(idx)];
+		long bit = 1lu << BIT_INDEX(idx);
+
+		if (v)
+			*ptr |= bit;
+		else
+			*ptr &= ~bit;
+	}
+}
+
+bool bitmap_get(bitmap_t *bitmap, long idx) {
+	__assert(idx < bitmap->size);
+
+	long bit = 1lu << BIT_INDEX(idx);
+	return bitmap->data[BYTE_INDEX(idx)] & bit;
 }
 
 long bitmap_find_first_set(bitmap_t *bitmap) {