bitmap: Rework types and sizing macros

Go with "words" rather than explicitly referencing longs in the macros

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

diff --git a/ccan/bitmap/bitmap.h b/ccan/bitmap/bitmap.h
index a9f47abef2aa0cbadf3a45e5e1b832edbd5a4879..4189fbd4392a922fccf34062fb21bf1e261a1d13 100644 (file)
--- a/ccan/bitmap/bitmap.h
+++ b/ccan/bitmap/bitmap.h
@@ -5,20 +5,33 @@
 #include <stdbool.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdbool.h>
 #include <stdlib.h>
 #include <string.h>

+#include <limits.h>

 
 

-#define BITS_PER_LONG  (sizeof(unsigned long) * 8)
+typedef unsigned long bitmap_word;
+
+#define BITMAP_WORD_BITS       (sizeof(bitmap_word) * CHAR_BIT)
+#define BITMAP_NWORDS(_n)      (((_n) + BITMAP_WORD_BITS - 1) / BITMAP_WORD_BITS)

 
 /*
 
 /*

- * We use an unsigned long to get alignment, but wrap it in a
- * structure for type checking
+ * We wrap each word in a structure for type checking.

  */
 typedef struct {
  */
 typedef struct {

-       unsigned long l;
+       bitmap_word w;

 } bitmap;
 
 } bitmap;
 

-#define BYTE(_bm, _n)  (((unsigned char *)(_bm))[(_n) / 8])
-#define LONG(_bm, _n)  (((unsigned long *)(_bm))[(_n) / BITS_PER_LONG])
+static inline size_t bitmap_sizeof(int nbits)
+{
+       return BITMAP_NWORDS(nbits) * sizeof(bitmap_word);
+}
+
+static inline bitmap *bitmap_alloc(int nbits)
+{
+       return malloc(bitmap_sizeof(nbits));
+}
+
+#define BYTE(_bm, _n)  (((unsigned char *)(_bm))[(_n) / CHAR_BIT])

 #define BIT(_n)                (0x80 >> ((_n) % 8))
 #define BIT(_n)                (0x80 >> ((_n) % 8))

+#define WORD(_bm, _n)  ((_bm)[(_n) / BITMAP_WORD_BITS].w)

 
 #define BYTES(_nbits)  ((_nbits) / 8)
 #define BITS(_nbits)   ((~(0xff >> ((_nbits) % 8))) & 0xff)
 
 #define BYTES(_nbits)  ((_nbits) / 8)
 #define BITS(_nbits)   ((~(0xff >> ((_nbits) % 8))) & 0xff)


@@ -72,9 +85,9 @@ static inline void bitmap_copy(bitmap *dst, bitmap *src, int nbits)
                                         int nbits) \
        { \
                int n = 0; \
                                         int nbits) \
        { \
                int n = 0; \

-               while ((nbits - n) >= BITS_PER_LONG) { \
-                       LONG(dst, n) = LONG(src1, n) _op LONG(src2, n); \
-                       n += BITS_PER_LONG; \
+               while ((nbits - n) >= BITMAP_WORD_BITS) { \
+                       WORD(dst, n) = WORD(src1, n) _op WORD(src2, n); \
+                       n += BITMAP_WORD_BITS; \

                } \
                while ((nbits - n) >= 8) { \
                        BYTE(dst, n) = BYTE(src1, n) _op BYTE(src2, n); \
                } \
                while ((nbits - n) >= 8) { \
                        BYTE(dst, n) = BYTE(src1, n) _op BYTE(src2, n); \


@@ -98,9 +111,9 @@ static inline void bitmap_complement(bitmap *dst, bitmap *src, int nbits)
 {
        int n = 0;
 
 {
        int n = 0;
 

-       while ((nbits - n) >= BITS_PER_LONG) {
-               LONG(dst, n) = ~LONG(src, n);
-               n += BITS_PER_LONG;
+       while ((nbits - n) >= BITMAP_WORD_BITS) {
+               WORD(dst, n) = ~WORD(src, n);
+               n += BITMAP_WORD_BITS;

        }
        while ((nbits - n) >= 8) {
                BYTE(dst, n) = ~BYTE(src, n);
        }
        while ((nbits - n) >= 8) {
                BYTE(dst, n) = ~BYTE(src, n);


@@ -126,10 +139,10 @@ static inline bool bitmap_intersects(bitmap *src1, bitmap *src2, int nbits)
 {
        int n = 0;
 
 {
        int n = 0;
 

-       while ((nbits - n) >= BITS_PER_LONG) {
-               if (LONG(src1, n) & LONG(src2, n))
+       while ((nbits - n) >= BITMAP_WORD_BITS) {
+               if (WORD(src1, n) & WORD(src2, n))

                        return true;
                        return true;

-               n += BITS_PER_LONG;
+               n += BITMAP_WORD_BITS;

        }
        while ((nbits - n) >= 8) {
                if (BYTE(src1, n) & BYTE(src2, n))
        }
        while ((nbits - n) >= 8) {
                if (BYTE(src1, n) & BYTE(src2, n))


@@ -146,10 +159,10 @@ static inline bool bitmap_subset(bitmap *src1, bitmap *src2, int nbits)
 {
        int n = 0;
 
 {
        int n = 0;
 

-       while ((nbits - n) >= BITS_PER_LONG) {
-               if (LONG(src1, n) & ~LONG(src2, n))
+       while ((nbits - n) >= BITMAP_WORD_BITS) {
+               if (WORD(src1, n) & ~WORD(src2, n))

                        return false;
                        return false;

-               n += BITS_PER_LONG;
+               n += BITMAP_WORD_BITS;

        }
        while ((nbits - n) >= 8) {
                if (BYTE(src1, n) & ~BYTE(src2, n))
        }
        while ((nbits - n) >= 8) {
                if (BYTE(src1, n) & ~BYTE(src2, n))


@@ -166,10 +179,10 @@ static inline bool bitmap_full(bitmap *bitmap, int nbits)
 {
        int n = 0;
 
 {
        int n = 0;
 

-       while ((nbits - n) >= BITS_PER_LONG) {
-               if (LONG(bitmap, n) != -1UL)
+       while ((nbits - n) >= BITMAP_WORD_BITS) {
+               if (WORD(bitmap, n) != -1UL)

                        return false;
                        return false;

-               n += BITS_PER_LONG;
+               n += BITMAP_WORD_BITS;

        }
        while ((nbits - n) >= 8) {
                if (BYTE(bitmap, n) != 0xff)
        }
        while ((nbits - n) >= 8) {
                if (BYTE(bitmap, n) != 0xff)


@@ -187,10 +200,10 @@ static inline bool bitmap_empty(bitmap *bitmap, int nbits)
 {
        int n = 0;
 
 {
        int n = 0;
 

-       while ((nbits - n) >= BITS_PER_LONG) {
-               if (LONG(bitmap, n))
+       while ((nbits - n) >= BITMAP_WORD_BITS) {
+               if (WORD(bitmap, n))

                        return false;
                        return false;

-               n += BITS_PER_LONG;
+               n += BITMAP_WORD_BITS;

        }
        while ((nbits - n) >= 8) {
                if (BYTE(bitmap, n))
        }
        while ((nbits - n) >= 8) {
                if (BYTE(bitmap, n))


@@ -204,13 +217,8 @@ static inline bool bitmap_empty(bitmap *bitmap, int nbits)
 }
 
 
 }
 
 

-static inline bitmap *bitmap_alloc(int nbits)
-{
-       return malloc((nbits + 7) / 8);
-}
-

 #undef BYTE
 #undef BYTE

-#undef LONG
+#undef WORD

 #undef BIT
 #undef BYTES
 #undef BITS
 #undef BIT
 #undef BYTES
 #undef BITS