Changes corresponding to patch #841324 from Ian Brown:

[wxWidgets.git] / src / common / hashmap.cpp

diff --git a/src/common/hashmap.cpp b/src/common/hashmap.cpp
index 04cbd63111d81ad523d6d9b97532cfd64d141493..098d789ac776ba88a65af76ba12e995d73cacfad 100644 (file)
--- a/src/common/hashmap.cpp
+++ b/src/common/hashmap.cpp
@@ -2,14 +2,14 @@
 // Name:        hashmap.cpp
 // Purpose:     wxHashMap implementation
 // Author:      Mattia Barbon
-// Modified by: 
+// Modified by:
 // Created:     29/01/2002
 // RCS-ID:      $Id$
 // Copyright:   (c) Mattia Barbon
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
-#ifdef __GNUG__
+#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
 #pragma implementation "hashmap.h"
 #endif
 
@@ -22,8 +22,6 @@
 
 #include "wx/hashmap.h"
 
-#include <assert.h>
-
 /* FYI: This is the "One-at-a-Time" algorithm by Bob Jenkins */
 /* from requirements by Colin Plumb. */
 /* (http://burtleburtle.net/bob/hash/doobs.html) */
@@ -63,7 +61,7 @@ unsigned long wxStringHash::charStringHash( const char* k )
 #endif
 
 /* from SGI STL */
-const unsigned long _wxHashTableBase2::s_primes[prime_count] =
+const unsigned long _wxHashTableBase2::ms_primes[prime_count] =
 {
     7ul,          13ul,         29ul,
     53ul,         97ul,         193ul,       389ul,       769ul,
@@ -76,7 +74,7 @@ const unsigned long _wxHashTableBase2::s_primes[prime_count] =
 
 unsigned long _wxHashTableBase2::GetNextPrime( unsigned long n )
 {
-    const unsigned long* ptr = &s_primes[0];
+    const unsigned long* ptr = &ms_primes[0];
     for( size_t i = 0; i < prime_count; ++i, ++ptr )
     {
         if( n < *ptr )
@@ -84,14 +82,15 @@ unsigned long _wxHashTableBase2::GetNextPrime( unsigned long n )
     }
 
     /* someone might try to alloc a 2^32-element hash table */
-    assert(0);
+    wxFAIL_MSG( _T("hash table too big?") );
+
     /* quiet warning */
     return 0;
 }
 
 unsigned long _wxHashTableBase2::GetPreviousPrime( unsigned long n )
 {
-    const unsigned long* ptr = &s_primes[prime_count - 1];
+    const unsigned long* ptr = &ms_primes[prime_count - 1];
 
     for( size_t i = 0; i < prime_count; ++i, --ptr )
     {
@@ -129,9 +128,20 @@ void _wxHashTableBase2::CopyHashTable( _wxHashTable_NodeBase** srcTable,
                                        size_t srcBuckets,
                                        _wxHashTableBase2* dst,
                                        _wxHashTable_NodeBase** dstTable,
+                                       size_t dstBuckets,
                                        BucketFromNode func, ProcessNode proc )
 {
-    for( size_t i = 0; i < srcBuckets; ++i )
+    // for compatibility with wxHashTable (to avoid reimplementig it
+    // from scratch), we need to preserve the order of nodes in a
+    // source bucket when copying the table, hence, to avoid
+    // allocating an auxiliary table we use a circular list for each
+    // bucket, and we keep the *tail* of each list in dstTable[i], to
+    // be able to append nodes in O(1) time. Wen we're done copying,
+    // we adjust dstTable[i] to point at the head of the list and we
+    // break the circular list into a linear one.
+    size_t i;
+
+    for( i = 0; i < srcBuckets; ++i )
     {
         _wxHashTable_NodeBase* nextnode;
 
@@ -141,8 +151,24 @@ void _wxHashTableBase2::CopyHashTable( _wxHashTable_NodeBase** srcTable,
 
             nextnode = node->m_nxt;
             _wxHashTable_NodeBase* newnode = proc( node );
-            newnode->m_nxt = dstTable[bucket];
-            dstTable[bucket] = newnode;
+            if( dstTable[bucket] )
+            {
+                newnode->m_nxt = dstTable[bucket]->m_nxt; // head of the list
+                dstTable[bucket]->m_nxt = newnode;
+                dstTable[bucket] = newnode;
+            }
+            else
+                dstTable[bucket] = newnode->m_nxt = newnode;
+        }
+    }
+
+    for( i = 0; i < dstBuckets; ++i )
+    {
+        if( dstTable[i] )
+        {
+            _wxHashTable_NodeBase* tmp = dstTable[i];
+            dstTable[i] = dstTable[i]->m_nxt;
+            tmp->m_nxt = NULL;
         }
     }
 }