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-rw-r--r--tools/libxc/xc_bitops.h63
1 files changed, 63 insertions, 0 deletions
diff --git a/tools/libxc/xc_bitops.h b/tools/libxc/xc_bitops.h
new file mode 100644
index 0000000000..d8e0c168d7
--- /dev/null
+++ b/tools/libxc/xc_bitops.h
@@ -0,0 +1,63 @@
+#ifndef XC_BITOPS_H
+#define XC_BITOPS_H 1
+
+/* bitmap operations for single threaded access */
+
+#include <stdlib.h>
+#include <string.h>
+
+#define BITS_PER_LONG (sizeof(unsigned long) * 8)
+#define ORDER_LONG (sizeof(unsigned long) == 4 ? 5 : 6)
+
+#define BITMAP_ENTRY(_nr,_bmap) ((_bmap))[(_nr)/BITS_PER_LONG]
+#define BITMAP_SHIFT(_nr) ((_nr) % BITS_PER_LONG)
+
+/* calculate required space for number of longs needed to hold nr_bits */
+static inline int bitmap_size(int nr_bits)
+{
+ int nr_long, nr_bytes;
+ nr_long = (nr_bits + BITS_PER_LONG - 1) >> ORDER_LONG;
+ nr_bytes = nr_long * sizeof(unsigned long);
+ return nr_bytes;
+}
+
+static inline unsigned long *bitmap_alloc(int nr_bits)
+{
+ return calloc(1, bitmap_size(nr_bits));
+}
+
+static inline void bitmap_clear(unsigned long *addr, int nr_bits)
+{
+ memset(addr, 0, bitmap_size(nr_bits));
+}
+
+static inline int test_bit(int nr, unsigned long *addr)
+{
+ return (BITMAP_ENTRY(nr, addr) >> BITMAP_SHIFT(nr)) & 1;
+}
+
+static inline void clear_bit(int nr, unsigned long *addr)
+{
+ BITMAP_ENTRY(nr, addr) &= ~(1UL << BITMAP_SHIFT(nr));
+}
+
+static inline void set_bit(int nr, unsigned long *addr)
+{
+ BITMAP_ENTRY(nr, addr) |= (1UL << BITMAP_SHIFT(nr));
+}
+
+static inline int test_and_clear_bit(int nr, unsigned long *addr)
+{
+ int oldbit = test_bit(nr, addr);
+ clear_bit(nr, addr);
+ return oldbit;
+}
+
+static inline int test_and_set_bit(int nr, unsigned long *addr)
+{
+ int oldbit = test_bit(nr, addr);
+ set_bit(nr, addr);
+ return oldbit;
+}
+
+#endif /* XC_BITOPS_H */