* generic hash functions
*/
-#ifndef SATSOLVER_HASH_H
-#define SATSOLVER_HASH_H
+#ifndef LIBSOLV_HASH_H
+#define LIBSOLV_HASH_H
#include "pooltypes.h"
+#ifdef __cplusplus
+extern "C" {
+#endif
+
/* value of a hash */
typedef unsigned int Hashval;
-/* mask for hash, used as modulo operator to ensure 'wrapping' of hash
- values -> hash table */
-typedef unsigned int Hashmask;
/* inside the hash table, Ids are stored. Hash maps: string -> hash -> Id */
typedef Id *Hashtable;
return r;
}
+static inline Hashval
+strnhash(const char *str, unsigned len)
+{
+ Hashval r = 0;
+ unsigned int c;
+ while (len-- && (c = *(const unsigned char *)str++) != 0)
+ r += (r << 3) + c;
+ return r;
+}
+
+static inline Hashval
+strhash_cont(const char *str, Hashval r)
+{
+ unsigned int c;
+ while ((c = *(const unsigned char *)str++) != 0)
+ r += (r << 3) + c;
+ return r;
+}
+
+
/* hash for rel
* rel -> hash
*/
/* compute bitmask for value
- * returns smallest (2^n-1) > num
- *
+ * returns smallest (2^n-1) > 2 * num + 3
+ *
* used for Hashtable 'modulo' operation
- */
-static inline Hashmask
+ */
+static inline Hashval
mkmask(unsigned int num)
{
- num *= 2;
+ num = num * 2 + 3;
while (num & (num - 1))
num &= num - 1;
return num * 2 - 1;
}
-#endif /* SATSOLVER_HASH_H */
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LIBSOLV_HASH_H */