WIP

src/lib/include/bitmap.h

@@ -0,0 +1,49 @@
+#pragma once
+
+#include <stddef.h>
+#include <stdint.h>
+#include <limits.h>
+#include "macros.h"
+
+struct bitmap {
+    size_t bit_count;
+    uint32_t* data;
+};
+
+/* buf:      buffer to use for bitmap
+ * buf_size: size of buffer in bytes */
+#define BITMAP_ATTACH(buf, buf_size) (struct bitmap){.bit_count = buf_size * CHAR_BIT, .data = buf}
+
+static inline int bitmap_set(struct bitmap* bitmap, size_t index)
+{
+    constexpr size_t bits_per_index = sizeof (bitmap->data[0]) * CHAR_BIT;
+    _Static_assert(bits_per_index == 32);
+    if (unlikely(index > bitmap->bit_count)) {
+        return -1;
+    }
+    bitmap->data[index / bits_per_index] |= (1 << (index % bits_per_index));
+    return 0;
+}
+
+static inline int bitmap_unset(struct bitmap* bitmap, size_t index)
+{
+    constexpr size_t bits_per_index = sizeof (bitmap->data[0]) * CHAR_BIT;
+    if (unlikely(index > bitmap->bit_count)) {
+        return -1;
+    }
+    bitmap->data[index / bits_per_index] &= ~(1 << (index % bits_per_index));
+    return 0;
+}
+
+static inline int bitmap_get(struct bitmap* bitmap, size_t index)
+{
+    constexpr size_t bits_per_index = sizeof (bitmap->data[0]) * CHAR_BIT;
+    if (unlikely(index > bitmap->bit_count)) {
+        return -1; 
+    }
+    return !!(bitmap->data[index / bits_per_index] & (1ULL << (index % bits_per_index)));
+}
+
+int bitmap_set_range(struct bitmap* bitmap, size_t begin, size_t end);
+int bitmap_clear_range(struct bitmap* bitmap, size_t begin, size_t end);
+int bitmap_range_empty(struct bitmap* bitmap, size_t begin, size_t end);