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authorLaurent Bercot <ska-skaware@skarnet.org>2014-09-18 18:55:44 +0000
committerLaurent Bercot <ska-skaware@skarnet.org>2014-09-18 18:55:44 +0000
commit3534b428629be185e096be99e3bd5fdfe32d5544 (patch)
tree210ef3198ed66bc7f7b7bf6a85e4579f455e5a36 /src/libstddjb/bitarray_not.c
downloadskalibs-3534b428629be185e096be99e3bd5fdfe32d5544.tar.xz
initial commit with rc for skalibs-2.0.0.0
Diffstat (limited to 'src/libstddjb/bitarray_not.c')
-rw-r--r--src/libstddjb/bitarray_not.c18
1 files changed, 18 insertions, 0 deletions
diff --git a/src/libstddjb/bitarray_not.c b/src/libstddjb/bitarray_not.c
new file mode 100644
index 0000000..4bd95ad
--- /dev/null
+++ b/src/libstddjb/bitarray_not.c
@@ -0,0 +1,18 @@
+/* ISC license. */
+
+#include <skalibs/bitarray.h>
+
+void bitarray_not (register unsigned char *s, register unsigned int a, register unsigned int b)
+{
+ if (!b) return ;
+ b += a ;
+ if ((a >> 3) == ((b-1) >> 3))
+ s[a>>3] ^= ((1 << (a & 7)) - 1) ^ ((a << (b & 7)) - 1) ;
+ else
+ {
+ register unsigned int i = (a>>3) + 1 ;
+ s[a>>3] ^= ~((1 << (a & 7)) - 1) ;
+ for (; i < (b>>3) - 1 ; i++) s[i] = ~s[i] ;
+ s[b>>3] ^= (1 << (b & 7)) - 1 ;
+ }
+}