* Add fuzzy hashes implementation (with adler-32 roll hash and FNV-32 hash)

* Add test case for fuzzy hashing check

1 files changed, 40 insertions, 0 deletions

diff --git a/src/fuzzy.h b/src/fuzzy.h
new file mode 100644
index 000000000..91e6512c6
--- /dev/null
+++ b/src/fuzzy.h
@@ -0,0 +1,40 @@
+/**
+ * @file fuzzy.h
+ * Fuzzy hashes API
+ */
+
+#ifndef RSPAMD_FUZZY_H
+#define RSPAMD_FUZZY_H
+
+#include "config.h"
+#include "mem_pool.h"
+#include "fstring.h"
+
+#define FUZZY_HASHLEN 64
+
+typedef struct fuzzy_hash_s {
+	char hash_pipe[FUZZY_HASHLEN];			/**< result hash					*/
+	uint32_t block_size;					/**< current blocksize				*/
+	uint32_t rh;							/**< roll hash value				*/
+	uint32_t h;								/**< hash of block					*/
+	uint32_t hi;							/**< current index in hash pipe		*/
+} fuzzy_hash_t;
+
+/**
+ * Calculate fuzzy hash for specified string
+ * @param in input string
+ * @param pool pool object
+ * @return fuzzy_hash object allocated in pool
+ */
+fuzzy_hash_t * fuzzy_init (f_str_t *in, memory_pool_t *pool);
+
+/**
+ * Compare score of difference between two hashes 
+ * @param h1 first hash
+ * @param h2 second hash
+ * @return result in percents 0 - different hashes, 100 - identical hashes 
+ */
+int fuzzy_compare_hashes (fuzzy_hash_t *h1, fuzzy_hash_t *h2);
+
+
+#endif