src/gallium/auxiliary/util/u_bitmask.h

   1 /**************************************************************************
   2  *
   3  * Copyright 2009 VMware, Inc.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28 /**
  29  * @file
  30  * Generic bitmask.
  31  *
  32  * @author Jose Fonseca <jfonseca@vmware.com>
  33  */
  34
  35 #ifndef U_HANDLE_BITMASK_H_
  36 #define U_HANDLE_BITMASK_H_
  37
  38
  39 #ifdef __cplusplus
  40 extern "C" {
  41 #endif
  42
  43
  44 #define UTIL_BITMASK_INVALID_INDEX (~0U)
  45
  46
  47 /**
  48  * Abstract data type to represent arbitrary set of bits.
  49  */
  50 struct util_bitmask;
  51
  52
  53 struct util_bitmask *
  54 util_bitmask_create(void);
  55
  56
  57 /**
  58  * Search a cleared bit and set it.
  59  *
  60  * It searches for the first cleared bit.
  61  *
  62  * Returns the bit index on success, or UTIL_BITMASK_INVALID_INDEX on out of
  63  * memory growing the bitmask.
  64  */
  65 unsigned
  66 util_bitmask_add(struct util_bitmask *bm);
  67
  68 /**
  69  * Set a bit.
  70  *
  71  * Returns the input index on success, or UTIL_BITMASK_INVALID_INDEX on out of
  72  * memory growing the bitmask.
  73  */
  74 unsigned
  75 util_bitmask_set(struct util_bitmask *bm,
  76                  unsigned index);
  77
  78 void
  79 util_bitmask_clear(struct util_bitmask *bm,
  80                    unsigned index);
  81
  82 boolean
  83 util_bitmask_get(struct util_bitmask *bm,
  84                  unsigned index);
  85
  86
  87 void
  88 util_bitmask_destroy(struct util_bitmask *bm);
  89
  90
  91 /**
  92  * Search for the first set bit.
  93  *
  94  * Returns UTIL_BITMASK_INVALID_INDEX if a set bit cannot be found.
  95  */
  96 unsigned
  97 util_bitmask_get_first_index(struct util_bitmask *bm);
  98
  99
 100 /**
 101  * Search for the first set bit, starting from the giving index.
 102  *
 103  * Returns UTIL_BITMASK_INVALID_INDEX if a set bit cannot be found.
 104  */
 105 unsigned
 106 util_bitmask_get_next_index(struct util_bitmask *bm,
 107                             unsigned index);
 108
 109
 110 #ifdef __cplusplus
 111 }
 112 #endif
 113
 114 #endif /* U_HANDLE_BITMASK_H_ */