Code cleanup

6 files changed, 27 insertions, 184 deletions

diff --git a/src/include/ndpi_api.h b/src/include/ndpi_api.h
index a1f4e387b..fa7f77f33 100644
--- a/src/include/ndpi_api.h
+++ b/src/include/ndpi_api.h
@@ -1799,7 +1799,8 @@ extern "C" {
 
   u_int32_t ndpi_crc32(const void* data, size_t n_bytes);
   u_int32_t ndpi_nearest_power_of_two(u_int32_t x);
-  
+  u_int32_t ndpi_hash_string(char *str);
+    
   /* ******************************* */
 
   int ndpi_des_init(struct ndpi_des_struct *des, double alpha, double beta, float significance);
@@ -2059,20 +2060,6 @@ extern "C" {
   u_int32_t    ndpi_filter_cardinality(ndpi_filter *f);
   
   /* ******************************* */
- 
-  /*
-    Efficient (space and speed) probabilitic datastructure
-    for exact string searching with a false positive rate
-    of 5 * 10 ^ -8
-  */
-  ndpi_string_search* ndpi_string_search_alloc();
-  void                ndpi_string_search_free(ndpi_string_search *s);
-  u_int32_t           ndpi_string_search_size(ndpi_string_search *s);
-  bool                ndpi_string_search_add(ndpi_string_search *s, char *string);
-  bool                ndpi_string_search_contains(ndpi_string_search *s, char *string);
-  u_int32_t           ndpi_string_search_cardinality(ndpi_string_search *f);
-
-  /* ******************************* */
 
   /*
     Efficient (space and speed) probabilitic datastructure
diff --git a/src/include/ndpi_typedefs.h b/src/include/ndpi_typedefs.h
index 75df402ef..bece570cc 100644
--- a/src/include/ndpi_typedefs.h
+++ b/src/include/ndpi_typedefs.h
@@ -2031,11 +2031,6 @@ typedef void ndpi_bitmap;
 typedef void ndpi_bitmap_iterator;
 typedef void ndpi_filter;
 
-typedef struct {
-  ndpi_filter *filter[2 /* direct and reverse */];
-} ndpi_string_search;
-
-
 #define MAX_NUM_NDPI_DOMAIN_CLASSIFICATIONS  16
 
 /* **************************************** */
diff --git a/src/lib/ndpi_domain_classify.c b/src/lib/ndpi_domain_classify.c
index 8b66c940e..df82cdabb 100644
--- a/src/lib/ndpi_domain_classify.c
+++ b/src/lib/ndpi_domain_classify.c
@@ -103,29 +103,6 @@ static u_int32_t ndpi_domain_search_size(ndpi_domain_search *search) {
 
 /* ********************************************************** */
 
-/*
-  https://en.wikipedia.org/wiki/Jenkins_hash_function
-
-  See also http://burtleburtle.net/bob/hash/spooky.html
-*/
-static inline u_int32_t ndpi_hash_string(char *domain) {
-  u_int32_t hash, i;
-
-  for(hash = i = 0; domain[i] != '\0'; ++i) {
-    hash += domain[i];
-    hash += (hash << 10);
-    hash ^= (hash >> 6);
-  }
-
-  hash += (hash << 3);
-  hash ^= (hash >> 11);
-  hash += (hash << 15);
-
-  return(hash);
-}
-
-/* ********************************************************** */
-
 /* NOTE: domain will be modified: copy it if necessary */
 static bool ndpi_domain_search_add(ndpi_domain_search *search, char *domain) {
   char *elem;
diff --git a/src/lib/ndpi_filter.c b/src/lib/ndpi_filter.c
index 5c4ff62bd..334d041b8 100644
--- a/src/lib/ndpi_filter.c
+++ b/src/lib/ndpi_filter.c
@@ -58,7 +58,7 @@ bool ndpi_filter_add(ndpi_filter *f, u_int32_t value) {
 /* ******************************************* */
 
 bool ndpi_filter_add_string(ndpi_filter *f, char *string) {
-  return(ndpi_filter_add(f, MurmurHash(string, strlen(string), 0xD6DFE7)));
+  return(ndpi_filter_add(f, ndpi_hash_string(string)));
 }
 
 /* ******************************************* */
@@ -76,7 +76,7 @@ bool ndpi_filter_contains(ndpi_filter *f, u_int32_t value) {
 /* ******************************************* */
 
 bool ndpi_filter_contains_string(ndpi_filter *f, char *string) {
-  return(ndpi_filter_contains(f, MurmurHash(string, strlen(string), 0xD6DFE7)));
+  return(ndpi_filter_contains(f, ndpi_hash_string(string)));
 }
 
 /* ******************************************* */
diff --git a/src/lib/ndpi_string_search.c b/src/lib/ndpi_string_search.c
deleted file mode 100644
index 76c9bb0de..000000000
--- a/src/lib/ndpi_string_search.c
+++ /dev/null
@@ -1,139 +0,0 @@
-/*
- * ndpi_string_search.c
- *
- * Copyright (C) 2011-23 - ntop.org and contributors
- *
- * This file is part of nDPI, an open source deep packet inspection
- * library based on the OpenDPI and PACE technology by ipoque GmbH
- *
- * nDPI is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * nDPI is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public License
- * along with nDPI.  If not, see <http://www.gnu.org/licenses/>.
- *
- */
-
-
-#include <stdlib.h>
-#include <errno.h>
-#include <math.h>
-#include <sys/types.h>
-
-#include "ndpi_config.h"
-#include "ndpi_api.h"
-#include "ndpi_includes.h"
-#include "ndpi_encryption.h"
-
-/* ******************************************* */
-
-ndpi_string_search* ndpi_string_search_alloc() {
-  ndpi_string_search *s = (ndpi_string_search*)ndpi_malloc(sizeof(ndpi_string_search));
-  int i;
-
-  if(!s) return(NULL);
-
-  for(i=0; i<2; i++)
-    s->filter[i] = ndpi_filter_alloc();
-
-  return(s);
-}
-
-/* ******************************************* */
-
-void ndpi_string_search_free(ndpi_string_search *_s) {
-  if(_s != NULL) {
-    ndpi_string_search *s = (ndpi_string_search*)_s;
-    int i;
-
-    for(i=0; i<2; i++)
-      ndpi_string_search_free(s->filter[i]);
-
-    ndpi_free(s);
-  }
-}
-
-/* ******************************************* */
-
-u_int32_t ndpi_string_search_size(ndpi_string_search *s) {
-  if(s != NULL) {
-    int i;
-    u_int32_t total_len = 0;
-
-    for(i=0; i<2; i++)
-      total_len += ndpi_filter_size(s->filter[i]);
-
-    return(total_len);
-  } else
-    return(0);
-}
-
-/* ******************************************* */
-
-u_int32_t ndpi_string_search_cardinality(ndpi_string_search *s) {
-  return(s ? ndpi_filter_cardinality(s) : 0);
-}
-
-/* ********************************************************** */
-
-static u_int32_t hashval(char *domain, bool revert_string) {
-  u_int32_t ret = 0, shift_bit = 1;
-  int i;
-
-  if(revert_string) {
-    i = strlen(domain) - 1;
-
-    while(i >= 0) {
-      u_int32_t v = ((u_int32_t)domain[i]) << shift_bit;
-
-      i--, ret += v;
-      if(++shift_bit == 25) shift_bit = 0;
-    }
-  } else {
-    i = 0;
-
-    while(domain[i] != '\0') {
-      u_int32_t v = ((u_int32_t)domain[i]) << shift_bit;
-
-      i++, ret += v;
-      if(++shift_bit == 25) shift_bit = 0;
-    }
-  }
-
-  return(ret + i);
-}
-
-/* ******************************************* */
-
-bool ndpi_string_search_add(ndpi_string_search *s, char *string) {
-  if(s != NULL) {
-    u_int32_t h0 = hashval(string, false), h1 = hashval(string, true);
-
-    ndpi_filter_add(s->filter[0], h0), ndpi_filter_add(s->filter[1], h1);
-    return(true);
-  } else
-    return(false);
-}
-
-/* ******************************************* */
-
-bool ndpi_string_search_contains(ndpi_string_search *s, char *string) {
-  if(s != NULL) {
-    u_int32_t h0 = hashval(string, false), h1;
-
-    if(!ndpi_filter_contains(s->filter[0], h0)) return(false);
-
-    h1 = hashval(string, true);
-    if(!ndpi_filter_contains(s->filter[1], h1)) return(false);
-
-    return(true);
-  } else
-    return(false);
-}
diff --git a/src/lib/ndpi_utils.c b/src/lib/ndpi_utils.c
index 35c0410e2..c62d82edf 100644
--- a/src/lib/ndpi_utils.c
+++ b/src/lib/ndpi_utils.c
@@ -3006,3 +3006,26 @@ u_int32_t ndpi_nearest_power_of_two(u_int32_t x) {
   x++;
   return(x);
 }
+
+/* ********************************************************** */
+
+/*
+  https://en.wikipedia.org/wiki/Jenkins_hash_function
+
+  See also http://burtleburtle.net/bob/hash/spooky.html
+*/
+u_int32_t ndpi_hash_string(char *str) {
+  u_int32_t hash, i;
+
+  for(hash = i = 0; str[i] != '\0'; ++i) {
+    hash += str[i];
+    hash += (hash << 10);
+    hash ^= (hash >> 6);
+  }
+
+  hash += (hash << 3);
+  hash ^= (hash >> 11);
+  hash += (hash << 15);
+
+  return(hash);
+}