/**************************************************************************
- *
+ *
* Copyright 2009 VMware, Inc.
* All Rights Reserved.
- *
+ *
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
- *
+ *
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
- *
+ *
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- *
+ *
**************************************************************************/
/**
* @file
* Generic bitmask implementation.
- *
+ *
* @author Jose Fonseca <jfonseca@vmware.com>
*/
#include "util/u_bitmask.h"
-typedef uint32_t util_bitmask_word;
+typedef uint32_t util_bitmask_word;
#define UTIL_BITMASK_INITIAL_WORDS 16
struct util_bitmask
{
util_bitmask_word *words;
-
+
/** Number of bits we can currently hold */
unsigned size;
-
+
/** Number of consecutive bits set at the start of the bitmask */
unsigned filled;
};
util_bitmask_create(void)
{
struct util_bitmask *bm;
-
+
bm = MALLOC_STRUCT(util_bitmask);
- if(!bm)
+ if (!bm)
return NULL;
-
- bm->words = (util_bitmask_word *)CALLOC(UTIL_BITMASK_INITIAL_WORDS, sizeof(util_bitmask_word));
- if(!bm->words) {
+
+ bm->words = (util_bitmask_word *)
+ CALLOC(UTIL_BITMASK_INITIAL_WORDS, sizeof(util_bitmask_word));
+ if (!bm->words) {
FREE(bm);
return NULL;
}
-
+
bm->size = UTIL_BITMASK_INITIAL_WORDS * UTIL_BITMASK_BITS_PER_WORD;
bm->filled = 0;
-
+
return bm;
}
/**
- * Resize the bitmask if necessary
+ * Resize the bitmask if necessary
*/
-static INLINE boolean
+static inline boolean
util_bitmask_resize(struct util_bitmask *bm,
unsigned minimum_index)
{
- unsigned minimum_size = minimum_index + 1;
+ const unsigned minimum_size = minimum_index + 1;
unsigned new_size;
util_bitmask_word *new_words;
/* Check integer overflow */
- if(!minimum_size)
+ if (!minimum_size)
return FALSE;
-
- if(bm->size >= minimum_size)
+
+ if (bm->size >= minimum_size)
return TRUE;
assert(bm->size % UTIL_BITMASK_BITS_PER_WORD == 0);
new_size = bm->size;
- while(new_size < minimum_size) {
+ while (new_size < minimum_size) {
new_size *= 2;
/* Check integer overflow */
- if(new_size < bm->size)
+ if (new_size < bm->size)
return FALSE;
}
assert(new_size);
assert(new_size % UTIL_BITMASK_BITS_PER_WORD == 0);
-
- new_words = (util_bitmask_word *)REALLOC((void *)bm->words,
- bm->size / UTIL_BITMASK_BITS_PER_BYTE,
- new_size / UTIL_BITMASK_BITS_PER_BYTE);
- if(!new_words)
+
+ new_words = (util_bitmask_word *)
+ REALLOC((void *)bm->words,
+ bm->size / UTIL_BITMASK_BITS_PER_BYTE,
+ new_size / UTIL_BITMASK_BITS_PER_BYTE);
+ if (!new_words)
return FALSE;
-
- memset(new_words + bm->size/UTIL_BITMASK_BITS_PER_WORD,
- 0,
+
+ memset(new_words + bm->size/UTIL_BITMASK_BITS_PER_WORD,
+ 0,
(new_size - bm->size)/UTIL_BITMASK_BITS_PER_BYTE);
-
+
bm->size = new_size;
bm->words = new_words;
-
+
return TRUE;
}
/**
- * Lazily update the filled.
+ * Check if we can increment the filled counter.
*/
-static INLINE void
+static inline void
util_bitmask_filled_set(struct util_bitmask *bm,
unsigned index)
{
assert(bm->filled <= bm->size);
assert(index < bm->size);
-
- if(index == bm->filled) {
+
+ if (index == bm->filled) {
++bm->filled;
assert(bm->filled <= bm->size);
}
}
-static INLINE void
+
+/**
+ * Check if we need to decrement the filled counter.
+ */
+static inline void
util_bitmask_filled_unset(struct util_bitmask *bm,
unsigned index)
{
assert(bm->filled <= bm->size);
assert(index < bm->size);
-
- if(index < bm->filled)
+
+ if (index < bm->filled)
bm->filled = index;
}
unsigned word;
unsigned bit;
util_bitmask_word mask;
-
+
assert(bm);
- /* linear search for an empty index */
+ /* linear search for an empty index, starting at filled position */
word = bm->filled / UTIL_BITMASK_BITS_PER_WORD;
bit = bm->filled % UTIL_BITMASK_BITS_PER_WORD;
mask = 1 << bit;
- while(word < bm->size / UTIL_BITMASK_BITS_PER_WORD) {
- while(bit < UTIL_BITMASK_BITS_PER_WORD) {
- if(!(bm->words[word] & mask))
+ while (word < bm->size / UTIL_BITMASK_BITS_PER_WORD) {
+ while (bit < UTIL_BITMASK_BITS_PER_WORD) {
+ if (!(bm->words[word] & mask))
goto found;
++bm->filled;
++bit;
found:
/* grow the bitmask if necessary */
- if(!util_bitmask_resize(bm, bm->filled))
+ if (!util_bitmask_resize(bm, bm->filled))
return UTIL_BITMASK_INVALID_INDEX;
assert(!(bm->words[word] & mask));
unsigned
-util_bitmask_set(struct util_bitmask *bm,
+util_bitmask_set(struct util_bitmask *bm,
unsigned index)
{
unsigned word;
unsigned bit;
util_bitmask_word mask;
-
+
assert(bm);
-
+
/* grow the bitmask if necessary */
- if(!util_bitmask_resize(bm, index))
+ if (!util_bitmask_resize(bm, index))
return UTIL_BITMASK_INVALID_INDEX;
word = index / UTIL_BITMASK_BITS_PER_WORD;
bm->words[word] |= mask;
util_bitmask_filled_set(bm, index);
-
+
return index;
}
void
-util_bitmask_clear(struct util_bitmask *bm,
+util_bitmask_clear(struct util_bitmask *bm,
unsigned index)
{
unsigned word;
unsigned bit;
util_bitmask_word mask;
-
+
assert(bm);
-
- if(index >= bm->size)
+
+ if (index >= bm->size)
return;
word = index / UTIL_BITMASK_BITS_PER_WORD;
mask = 1 << bit;
bm->words[word] &= ~mask;
-
+
util_bitmask_filled_unset(bm, index);
}
boolean
-util_bitmask_get(struct util_bitmask *bm,
+util_bitmask_get(struct util_bitmask *bm,
unsigned index)
{
- unsigned word = index / UTIL_BITMASK_BITS_PER_WORD;
- unsigned bit = index % UTIL_BITMASK_BITS_PER_WORD;
- util_bitmask_word mask = 1 << bit;
-
+ const unsigned word = index / UTIL_BITMASK_BITS_PER_WORD;
+ const unsigned bit = index % UTIL_BITMASK_BITS_PER_WORD;
+ const util_bitmask_word mask = 1 << bit;
+
assert(bm);
-
- if(index < bm->filled) {
+
+ if (index < bm->filled) {
assert(bm->words[word] & mask);
return TRUE;
}
- if(index >= bm->size)
+ if (index >= bm->size)
return FALSE;
- if(bm->words[word] & mask) {
+ if (bm->words[word] & mask) {
util_bitmask_filled_set(bm, index);
return TRUE;
}
unsigned
-util_bitmask_get_next_index(struct util_bitmask *bm,
+util_bitmask_get_next_index(struct util_bitmask *bm,
unsigned index)
{
unsigned word = index / UTIL_BITMASK_BITS_PER_WORD;
unsigned bit = index % UTIL_BITMASK_BITS_PER_WORD;
util_bitmask_word mask = 1 << bit;
- if(index < bm->filled) {
+ if (index < bm->filled) {
assert(bm->words[word] & mask);
return index;
}
- if(index >= bm->size) {
+ if (index >= bm->size) {
return UTIL_BITMASK_INVALID_INDEX;
}
/* Do a linear search */
- while(word < bm->size / UTIL_BITMASK_BITS_PER_WORD) {
- while(bit < UTIL_BITMASK_BITS_PER_WORD) {
- if(bm->words[word] & mask) {
- if(index == bm->filled) {
+ while (word < bm->size / UTIL_BITMASK_BITS_PER_WORD) {
+ while (bit < UTIL_BITMASK_BITS_PER_WORD) {
+ if (bm->words[word] & mask) {
+ if (index == bm->filled) {
++bm->filled;
assert(bm->filled <= bm->size);
}
bit = 0;
mask = 1;
}
-
+
return UTIL_BITMASK_INVALID_INDEX;
}
void
util_bitmask_destroy(struct util_bitmask *bm)
{
- assert(bm);
-
- FREE(bm->words);
- FREE(bm);
+ if (bm) {
+ FREE(bm->words);
+ FREE(bm);
+ }
}
-
projects / mesa.git / blobdiff