X-Git-Url: http://git.indexdata.com/?a=blobdiff_plain;f=src%2Ftermlists.c;h=b40e5b026cf413e0edab895be20b731e282bebbb;hb=61027e68ea2f9c307a289b9cf8cc1be2cceb13d3;hp=027d057018c52cd962a9b9915d8a0fb625169387;hpb=bdf63c9b34f8a40edec11d50dc71454c0b8daf32;p=pazpar2-moved-to-github.git

diff --git a/src/termlists.c b/src/termlists.c
index 027d057..b40e5b0 100644
--- a/src/termlists.c
+++ b/src/termlists.c
@@ -1,16 +1,32 @@
-/*
- * $Id: termlists.c,v 1.4 2007-01-10 10:04:23 adam Exp $
- */
+/* This file is part of Pazpar2.
+   Copyright (C) 2006-2010 Index Data
 
-#include <stdlib.h>
-#include <string.h>
-#include <yaz/yaz-util.h>
+Pazpar2 is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+Pazpar2 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 General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
 
 #if HAVE_CONFIG_H
-#include <cconfig.h>
+#include <config.h>
 #endif
 
+#include <stdlib.h>
+#include <string.h>
+#include <yaz/yaz-util.h>
+
 #include "termlists.h"
+#include "jenkins_hash.h"
 
 // Discussion:
 // As terms are found in incoming records, they are added to (or updated in) a
@@ -26,8 +42,7 @@ struct termlist_bucket
 struct termlist
 {
     struct termlist_bucket **hashtable;
-    int hashtable_size;
-    int hashmask;
+    unsigned hash_size;
 
     struct termlist_score **highscore;
     int highscore_size;
@@ -37,42 +52,14 @@ struct termlist
     NMEM nmem;
 };
 
-
-// Jenkins one-at-a-time hash (from wikipedia)
-static unsigned int hash(const unsigned char *key)
-{
-    unsigned int hash = 0;
-
-    while (*key)
-    {
-        hash += *(key++);
-        hash += (hash << 10);
-        hash ^= (hash >> 6);
-    }
-    hash += (hash << 3);
-    hash ^= (hash >> 11);
-    hash += (hash << 15);
-    return hash;
-}
-
-struct termlist *termlist_create(NMEM nmem, int numterms, int highscore_size)
+struct termlist *termlist_create(NMEM nmem, int highscore_size)
 {
-    int hashsize = 1;
-    int halfnumterms;
-    struct termlist *res;
-
-    // Calculate a hash size smallest power of 2 larger than 50% of expected numterms
-    halfnumterms = numterms >> 1;
-    if (halfnumterms < 0)
-        halfnumterms = 1;
-    while (hashsize < halfnumterms)
-        hashsize <<= 1;
-    res = nmem_malloc(nmem, sizeof(struct termlist));
-    res->hashtable = nmem_malloc(nmem, hashsize * sizeof(struct termlist_bucket*));
-    memset(res->hashtable, 0, hashsize * sizeof(struct termlist_bucket*));
-    res->hashtable_size = hashsize;
+    struct termlist *res = nmem_malloc(nmem, sizeof(struct termlist));
+    res->hash_size = 399;
+    res->hashtable =
+        nmem_malloc(nmem, res->hash_size * sizeof(struct termlist_bucket*));
+    memset(res->hashtable, 0, res->hash_size * sizeof(struct termlist_bucket*));
     res->nmem = nmem;
-    res->hashmask = hashsize - 1; // Creates a bitmask
 
     res->highscore = nmem_malloc(nmem, highscore_size * sizeof(struct termlist_score *));
     res->highscore_size = highscore_size;
@@ -124,11 +111,19 @@ void termlist_insert(struct termlist *tl, const char *term)
 {
     unsigned int bucket;
     struct termlist_bucket **p;
+    char buf[256], *cp;
 
-    bucket = hash((unsigned char *)term) & tl->hashmask;
+    if (strlen(term) > 255)
+        return;
+    strcpy(buf, term);
+    /* chop right */
+    for (cp = buf + strlen(buf); cp != buf && strchr(",. -", cp[-1]); cp--)
+        cp[-1] = '\0';
+    
+    bucket = jenkins_hash((unsigned char *)buf) % tl->hash_size;
     for (p = &tl->hashtable[bucket]; *p; p = &(*p)->next)
     {
-        if (!strcmp(term, (*p)->term.term))
+        if (!strcmp(buf, (*p)->term.term))
         {
             (*p)->term.frequency++;
             update_highscore(tl, &((*p)->term));
@@ -139,7 +134,7 @@ void termlist_insert(struct termlist *tl, const char *term)
     {
         struct termlist_bucket *new = nmem_malloc(tl->nmem,
                 sizeof(struct termlist_bucket));
-        new->term.term = nmem_strdup(tl->nmem, term);
+        new->term.term = nmem_strdup(tl->nmem, buf);
         new->term.frequency = 1;
         new->next = 0;
         *p = new;
@@ -163,7 +158,9 @@ struct termlist_score **termlist_highscore(struct termlist *tl, int *len)
 /*
  * Local variables:
  * c-basic-offset: 4
+ * c-file-style: "Stroustrup"
  * indent-tabs-mode: nil
  * End:
  * vim: shiftwidth=4 tabstop=8 expandtab
  */
+