changed g_str_hash() to a 31 bit version based on a submission by Karl

Mon Feb 14 22:32:49 2000  Tim Janik  <timj@gtk.org>

        * gstring.c: changed g_str_hash() to a 31 bit version based on
        a submission by Karl Nelson and hand optimized ad absurdum by
        various people ;)

10 files changed, 68 insertions, 32 deletions

diff --git a/ChangeLog b/ChangeLog
index be4aa2601..0fce89cc4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Mon Feb 14 22:32:49 2000  Tim Janik  <timj@gtk.org>
+
+	* gstring.c: changed g_str_hash() to a 31 bit version based on
+	a submission by Karl Nelson and hand optimized ad absurdum by
+	various people ;)
+
 Fri Feb  4 19:39:38 2000  Tim Janik  <timj@gtk.org>
 
 	* configure.in: up version number to 1.2.7, interface age 7 and
diff --git a/ChangeLog.pre-2-0 b/ChangeLog.pre-2-0
index be4aa2601..0fce89cc4 100644
--- a/ChangeLog.pre-2-0
+++ b/ChangeLog.pre-2-0
@@ -1,3 +1,9 @@
+Mon Feb 14 22:32:49 2000  Tim Janik  <timj@gtk.org>
+
+	* gstring.c: changed g_str_hash() to a 31 bit version based on
+	a submission by Karl Nelson and hand optimized ad absurdum by
+	various people ;)
+
 Fri Feb  4 19:39:38 2000  Tim Janik  <timj@gtk.org>
 
 	* configure.in: up version number to 1.2.7, interface age 7 and
diff --git a/ChangeLog.pre-2-10 b/ChangeLog.pre-2-10
index be4aa2601..0fce89cc4 100644
--- a/ChangeLog.pre-2-10
+++ b/ChangeLog.pre-2-10
@@ -1,3 +1,9 @@
+Mon Feb 14 22:32:49 2000  Tim Janik  <timj@gtk.org>
+
+	* gstring.c: changed g_str_hash() to a 31 bit version based on
+	a submission by Karl Nelson and hand optimized ad absurdum by
+	various people ;)
+
 Fri Feb  4 19:39:38 2000  Tim Janik  <timj@gtk.org>
 
 	* configure.in: up version number to 1.2.7, interface age 7 and
diff --git a/ChangeLog.pre-2-12 b/ChangeLog.pre-2-12
index be4aa2601..0fce89cc4 100644
--- a/ChangeLog.pre-2-12
+++ b/ChangeLog.pre-2-12
@@ -1,3 +1,9 @@
+Mon Feb 14 22:32:49 2000  Tim Janik  <timj@gtk.org>
+
+	* gstring.c: changed g_str_hash() to a 31 bit version based on
+	a submission by Karl Nelson and hand optimized ad absurdum by
+	various people ;)
+
 Fri Feb  4 19:39:38 2000  Tim Janik  <timj@gtk.org>
 
 	* configure.in: up version number to 1.2.7, interface age 7 and
diff --git a/ChangeLog.pre-2-2 b/ChangeLog.pre-2-2
index be4aa2601..0fce89cc4 100644
--- a/ChangeLog.pre-2-2
+++ b/ChangeLog.pre-2-2
@@ -1,3 +1,9 @@
+Mon Feb 14 22:32:49 2000  Tim Janik  <timj@gtk.org>
+
+	* gstring.c: changed g_str_hash() to a 31 bit version based on
+	a submission by Karl Nelson and hand optimized ad absurdum by
+	various people ;)
+
 Fri Feb  4 19:39:38 2000  Tim Janik  <timj@gtk.org>
 
 	* configure.in: up version number to 1.2.7, interface age 7 and
diff --git a/ChangeLog.pre-2-4 b/ChangeLog.pre-2-4
index be4aa2601..0fce89cc4 100644
--- a/ChangeLog.pre-2-4
+++ b/ChangeLog.pre-2-4
@@ -1,3 +1,9 @@
+Mon Feb 14 22:32:49 2000  Tim Janik  <timj@gtk.org>
+
+	* gstring.c: changed g_str_hash() to a 31 bit version based on
+	a submission by Karl Nelson and hand optimized ad absurdum by
+	various people ;)
+
 Fri Feb  4 19:39:38 2000  Tim Janik  <timj@gtk.org>
 
 	* configure.in: up version number to 1.2.7, interface age 7 and
diff --git a/ChangeLog.pre-2-6 b/ChangeLog.pre-2-6
index be4aa2601..0fce89cc4 100644
--- a/ChangeLog.pre-2-6
+++ b/ChangeLog.pre-2-6
@@ -1,3 +1,9 @@
+Mon Feb 14 22:32:49 2000  Tim Janik  <timj@gtk.org>
+
+	* gstring.c: changed g_str_hash() to a 31 bit version based on
+	a submission by Karl Nelson and hand optimized ad absurdum by
+	various people ;)
+
 Fri Feb  4 19:39:38 2000  Tim Janik  <timj@gtk.org>
 
 	* configure.in: up version number to 1.2.7, interface age 7 and
diff --git a/ChangeLog.pre-2-8 b/ChangeLog.pre-2-8
index be4aa2601..0fce89cc4 100644
--- a/ChangeLog.pre-2-8
+++ b/ChangeLog.pre-2-8
@@ -1,3 +1,9 @@
+Mon Feb 14 22:32:49 2000  Tim Janik  <timj@gtk.org>
+
+	* gstring.c: changed g_str_hash() to a 31 bit version based on
+	a submission by Karl Nelson and hand optimized ad absurdum by
+	various people ;)
+
 Fri Feb  4 19:39:38 2000  Tim Janik  <timj@gtk.org>
 
 	* configure.in: up version number to 1.2.7, interface age 7 and
diff --git a/glib/gstring.c b/glib/gstring.c
index 0ae4fabd4..2274a6a23 100644
--- a/glib/gstring.c
+++ b/glib/gstring.c
@@ -67,26 +67,20 @@ g_str_equal (gconstpointer v, gconstpointer v2)
   return strcmp ((const gchar*) v, (const gchar*)v2) == 0;
 }
 
-/* a char* hash function from ASU */
+/* 31 bit hash function */
 guint
-g_str_hash (gconstpointer v)
+g_str_hash (gconstpointer key)
 {
-  const char *s = (char*)v;
-  const char *p;
-  guint h=0, g;
-
-  for(p = s; *p != '\0'; p += 1) {
-    h = ( h << 4 ) + *p;
-    if ( ( g = h & 0xf0000000 ) ) {
-      h = h ^ (g >> 24);
-      h = h ^ g;
-    }
-  }
-
-  return h /* % M */;
+  const char *p = key;
+  guint h = *p;
+  
+  if (h)
+    for (p += 1; *p != '\0'; p++)
+      h = (h << 5) - h + *p;
+  
+  return h;
 }
 
-
 /* String Chunks.
  */
 
diff --git a/gstring.c b/gstring.c
index 0ae4fabd4..2274a6a23 100644
--- a/gstring.c
+++ b/gstring.c
@@ -67,26 +67,20 @@ g_str_equal (gconstpointer v, gconstpointer v2)
   return strcmp ((const gchar*) v, (const gchar*)v2) == 0;
 }
 
-/* a char* hash function from ASU */
+/* 31 bit hash function */
 guint
-g_str_hash (gconstpointer v)
+g_str_hash (gconstpointer key)
 {
-  const char *s = (char*)v;
-  const char *p;
-  guint h=0, g;
-
-  for(p = s; *p != '\0'; p += 1) {
-    h = ( h << 4 ) + *p;
-    if ( ( g = h & 0xf0000000 ) ) {
-      h = h ^ (g >> 24);
-      h = h ^ g;
-    }
-  }
-
-  return h /* % M */;
+  const char *p = key;
+  guint h = *p;
+  
+  if (h)
+    for (p += 1; *p != '\0'; p++)
+      h = (h << 5) - h + *p;
+  
+  return h;
 }
 
-
 /* String Chunks.
  */