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#pragma once
/* Copyright © 2010 Christoph Sünderhauf
*
* This file is part of Xelix.
*
* Xelix is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Xelix is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Xelix. If not, see <http://www.gnu.org/licenses/>.
*/
#include "generic.h"
typedef struct {
uint32_t numbits;
/* an array large enough for numbits to fit in. Might
* (if numbits%8!=0) have some spare bits at the end
*/
uint32_t* bits;
} bitmap_t;
// creates a new bitmap.
// CONTENT IS RANDOM! - use bitmap_clearall() to clear the bitmap.
bitmap_t bitmap_init(uint32_t numbits);
// returns 1 or 0
uint8_t bitmap_get(bitmap_t bitmap, uint32_t bitnum);
// sets a bit (to 1)
void bitmap_set(bitmap_t bitmap, uint32_t bitnum);
// clears a bit (to 0)
void bitmap_clear(bitmap_t bitmap, uint32_t bitnum);
// clears every bit to 0
void bitmap_clearAll(bitmap_t bitmap);
// finds the first bit set to 0 returns 0 if no cleared bit found (0 is also returned if the first bit is cleared)
uint32_t bitmap_findFirstClear(bitmap_t bitmap);