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Diffstat (limited to 'src/lib/bitmap.c')
-rw-r--r--src/lib/bitmap.c61
1 files changed, 39 insertions, 22 deletions
diff --git a/src/lib/bitmap.c b/src/lib/bitmap.c
index 93ffda77..bf9bb99d 100644
--- a/src/lib/bitmap.c
+++ b/src/lib/bitmap.c
@@ -38,7 +38,8 @@
#define BITS_TO_LONGS(nr) \
DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(size_t))
-static size_t find_next_zero_bit(const size_t * addr, size_t nbits)
+static size_t find_next_zero_bit(const size_t * addr,
+ size_t nbits)
{
size_t tmp;
size_t start = 0;
@@ -65,13 +66,15 @@ static size_t find_next_zero_bit(const size_t * addr, size_t nbits)
return (start * BITS_PER_LONG) + pos;
}
-static void bitmap_zero(size_t * dst, size_t nbits)
+static void bitmap_zero(size_t * dst,
+ size_t nbits)
{
size_t len = BITS_TO_LONGS(nbits) * sizeof(size_t);
memset(dst, 0, len);
}
-static void bitmap_clear(size_t * map, size_t start)
+static void bitmap_clear(size_t * map,
+ size_t start)
{
size_t * p = map + BIT_WORD(start);
size_t mask = ~(1UL << (start % (BITS_PER_LONG)));
@@ -79,7 +82,8 @@ static void bitmap_clear(size_t * map, size_t start)
*p &= mask;
}
-static void bitmap_set(size_t * map, size_t start)
+static void bitmap_set(size_t * map,
+ size_t start)
{
size_t * p = map + BIT_WORD(start);
size_t mask = 1UL << (start % (BITS_PER_LONG));
@@ -94,7 +98,8 @@ struct bmp {
size_t * bitmap;
};
-struct bmp * bmp_create(size_t bits, ssize_t offset)
+struct bmp * bmp_create(size_t bits,
+ ssize_t offset)
{
struct bmp * tmp;
@@ -118,20 +123,15 @@ struct bmp * bmp_create(size_t bits, ssize_t offset)
return tmp;
}
-int bmp_destroy(struct bmp * b)
+void bmp_destroy(struct bmp * b)
{
if (b == NULL)
- return -1;
+ return;
- if (b->bitmap == NULL) {
- free(b);
- return -1;
- }
+ if (b->bitmap != NULL)
+ free(b->bitmap);
- free(b->bitmap);
free(b);
-
- return 0;
}
static ssize_t bad_id(struct bmp * b)
@@ -158,7 +158,8 @@ ssize_t bmp_allocate(struct bmp * b)
return id + b->offset;
}
-static bool is_id_valid(struct bmp * b, ssize_t id)
+static bool is_id_valid(struct bmp * b,
+ ssize_t id)
{
assert(b);
@@ -168,7 +169,17 @@ static bool is_id_valid(struct bmp * b, ssize_t id)
return true;
}
-bool bmp_is_id_valid(struct bmp * b, ssize_t id)
+static bool is_id_used(size_t * map,
+ size_t start)
+{
+ size_t * p = map + BIT_WORD(start);
+ size_t mask = 1UL << (start % (BITS_PER_LONG));
+
+ return (*p & mask) != 0;
+}
+
+bool bmp_is_id_valid(struct bmp * b,
+ ssize_t id)
{
if (b == NULL)
return false;
@@ -176,19 +187,25 @@ bool bmp_is_id_valid(struct bmp * b, ssize_t id)
return is_id_valid(b, id);
}
-int bmp_release(struct bmp * b, ssize_t id)
+int bmp_release(struct bmp * b,
+ ssize_t id)
{
- size_t rid;
-
if (b == NULL)
return -1;
if (!is_id_valid(b, id))
return -1;
- rid = id - b->offset;
-
- bitmap_clear(b->bitmap, rid);
+ bitmap_clear(b->bitmap, id - b->offset);
return 0;
}
+
+bool bmp_is_id_used(struct bmp * b,
+ ssize_t id)
+{
+ if (b == NULL)
+ return false;
+
+ return is_id_used(b->bitmap, id - b->offset);
+}