1 files changed, 24 insertions, 0 deletions
diff --git a/src/libstddjb/bitarray_clearsetn.c b/src/libstddjb/bitarray_clearsetn.c
new file mode 100644
index 0000000..b3f46f1
--- /dev/null
+++ b/src/libstddjb/bitarray_clearsetn.c
@@ -0,0 +1,24 @@
+/* ISC license. */
+
+#include <skalibs/bitarray.h>
+
+void bitarray_clearsetn (register unsigned char *s, register unsigned int a, register unsigned int b, register int h)
+{
+  if (!b) return ;
+  b += a ;
+  if ((a >> 3) == ((b-1) >> 3))
+  {
+    register unsigned char mask = ((1 << (a & 7)) - 1) ^ ((1 << (b & 7)) - 1) ;
+    if (h) s[a>>3] |= mask ; else s[a>>3] &= ~mask ;
+  }
+  else
+  {
+    register unsigned char mask = ~((1 << (a & 7)) - 1) ;
+    register unsigned int i = (a>>3) + 1 ;
+    if (h) s[a>>3] |= mask ; else s[a>>3] &= ~mask ;
+    mask = h ? 0xff : 0x00 ;
+    for (; i < b>>3 ; i++) s[i] = mask ;
+    mask = (1 << (b & 7)) - 1 ;
+    if (h) s[b>>3] |= mask ; else s[b>>3] &= ~mask ;
+  }
+}