Initial revision

1 files changed, 76 insertions, 0 deletions

diff --git a/Parser/bitset.c b/Parser/bitset.c
new file mode 100644
index 0000000..b43fb82
--- /dev/null
+++ b/Parser/bitset.c
@@ -0,0 +1,76 @@
+/* Bitset primitives */
+
+#include "PROTO.h"
+#include "malloc.h"
+#include "bitset.h"
+
+bitset
+newbitset(nbits)
+	int nbits;
+{
+	int nbytes = NBYTES(nbits);
+	bitset ss = NEW(BYTE, nbytes);
+	
+	if (ss == NULL)
+		fatal("no mem for bitset");
+	
+	ss += nbytes;
+	while (--nbytes >= 0)
+		*--ss = 0;
+	return ss;
+}
+
+void
+delbitset(ss)
+	bitset ss;
+{
+	DEL(ss);
+}
+
+int
+addbit(ss, ibit)
+	bitset ss;
+	int ibit;
+{
+	int ibyte = BIT2BYTE(ibit);
+	BYTE mask = BIT2MASK(ibit);
+	
+	if (ss[ibyte] & mask)
+		return 0; /* Bit already set */
+	ss[ibyte] |= mask;
+	return 1;
+}
+
+#if 0 /* Now a macro */
+int
+testbit(ss, ibit)
+	bitset ss;
+	int ibit;
+{
+	return (ss[BIT2BYTE(ibit)] & BIT2MASK(ibit)) != 0;
+}
+#endif
+
+int
+samebitset(ss1, ss2, nbits)
+	bitset ss1, ss2;
+	int nbits;
+{
+	int i;
+	
+	for (i = NBYTES(nbits); --i >= 0; )
+		if (*ss1++ != *ss2++)
+			return 0;
+	return 1;
+}
+
+void
+mergebitset(ss1, ss2, nbits)
+	bitset ss1, ss2;
+	int nbits;
+{
+	int i;
+	
+	for (i = NBYTES(nbits); --i >= 0; )
+		*ss1++ |= *ss2++;
+}