Patch: Playlistmanager

Hi,
the attached patch solves a bug in the playlist manager that getItem 
returns an invalid pointer.

It also cleans up the shuffle and does a common subexpression reduction.
The patch is tested and solves the problem without producing new ones.

have fun,
Ralf


diff -ur zinf-compiled/base/src/playlist.cpp zinf/base/src/playlist.cpp
--- zinf-compiled/base/src/playlist.cpp	2003-08-09 19:48:42.000000000 +0200
+++ zinf/base/src/playlist.cpp	2003-08-20 22:32:01.000000000 +0200
@@ -448,43 +448,21 @@
      if (!toBeShuffled)
          toBeShuffled = &m_shuffleList;

-    int max = toBeShuffled->size();
-    vector<PlaylistItem *> tempShuffled;
-
      srand((unsigned int)time(NULL));
+

-    int i;
-    vector<bool> usedList;
-    for (i = 0; i < max; i++)
-    {
-        usedList.push_back(false);
-    }
-
-    bool used = true;
-    int  index = 0;
-    int  lastindex = 0;
-
-    for (i = 0; i < max; i++)
-    {
-        while (used)
-        {
-            index = (int)((double)rand() / (RAND_MAX + 1.0) * max);
-            if (usedList[index] == false)
-                used = false;
-            if (max - i > 50 && abs(index - lastindex) < 10)
-                used = true;
-        }
-        usedList[index] = true;
-        PlaylistItem *dupe = (*toBeShuffled)[index];
-        tempShuffled.push_back(dupe);
-        used = true;
-        lastindex = index;
-    }
-
-    toBeShuffled->erase(toBeShuffled->begin(), toBeShuffled->end());
-    vector<PlaylistItem *>::iterator iter = tempShuffled.begin();
-    for (; iter != tempShuffled.end(); iter++)
-        toBeShuffled->push_back(*iter);
+    // --- shuffling is quite easy if you know how to do it :)
+
+    for( uint32_t i=0; i<toBeShuffled->size()-i; i++ ) {
+      int randIndex = i + (int)((double)rand() / (RAND_MAX + 1.0)
+                                * (toBeShuffled->size()-i) );
+
+      // exchange items
+      PlaylistItem* item = (*toBeShuffled)[i];
+      (*toBeShuffled)[i] = (*toBeShuffled)[randIndex];
+      (*toBeShuffled)[randIndex] = item;
+    }
+
  }

  Error PlaylistManager::SetCurrentItem(PlaylistItem* item)
@@ -494,7 +472,11 @@

  PlaylistItem*  PlaylistManager::GetCurrentItem()
  {
+    if( m_current == kInvalidIndex )
+      return NULL;
+
      PlaylistItem* result = NULL;
+
      m_mutex.Acquire();

      if(m_masterList.size())
@@ -1669,21 +1651,17 @@
          else
              stable_sort(m_activeList->begin(), m_activeList->end(), 
not2(PlaylistItemSort(key)));

-        m_sortKey = key;
-        m_sortType = type;
-
-        result = kError_NoErr;
      }
      else if(key == kPlaylistSortKey_Random)
      {
          ShuffleIt(m_activeList);
-
-        m_sortKey = key;
-        m_sortType = type;
-
-        result = kError_NoErr;
      }

+    m_sortKey = key;
+    m_sortType = type;
+
+    result = kError_NoErr;
+
      if(IsntError(result))
      {
          if(kPlaylistKey_MasterPlaylist == GetActivePlaylist() && 
currentItem)

diff -ur zinf-compiled/base/src/playlist.cpp zinf/base/src/playlist.cpp
--- zinf-compiled/base/src/playlist.cpp	2003-08-09 19:48:42.000000000 +0200
+++ zinf/base/src/playlist.cpp	2003-08-20 22:32:01.000000000 +0200
@@ -448,43 +448,21 @@
     if (!toBeShuffled)
         toBeShuffled = &m_shuffleList;
 
-    int max = toBeShuffled->size();
-    vector<PlaylistItem *> tempShuffled;
-
     srand((unsigned int)time(NULL));
+
     
-    int i;
-    vector<bool> usedList;
-    for (i = 0; i < max; i++)
-    {
-        usedList.push_back(false);
-    }
-
-    bool used = true;
-    int  index = 0;
-    int  lastindex = 0;
-
-    for (i = 0; i < max; i++) 
-    {
-        while (used)
-        {
-            index = (int)((double)rand() / (RAND_MAX + 1.0) * max);
-            if (usedList[index] == false)
-                used = false;
-            if (max - i > 50 && abs(index - lastindex) < 10)
-                used = true;
-        } 
-        usedList[index] = true;
-        PlaylistItem *dupe = (*toBeShuffled)[index];
-        tempShuffled.push_back(dupe);
-        used = true;
-        lastindex = index;
-    }
-
-    toBeShuffled->erase(toBeShuffled->begin(), toBeShuffled->end());
-    vector<PlaylistItem *>::iterator iter = tempShuffled.begin();
-    for (; iter != tempShuffled.end(); iter++) 
-        toBeShuffled->push_back(*iter);
+    // --- shuffling is quite easy if you know how to do it :)
+
+    for( uint32_t i=0; i<toBeShuffled->size()-i; i++ ) {
+      int randIndex = i + (int)((double)rand() / (RAND_MAX + 1.0) 
+                                * (toBeShuffled->size()-i) );
+
+      // exchange items
+      PlaylistItem* item = (*toBeShuffled)[i];
+      (*toBeShuffled)[i] = (*toBeShuffled)[randIndex];
+      (*toBeShuffled)[randIndex] = item;
+    }
+
 }
 
 Error PlaylistManager::SetCurrentItem(PlaylistItem* item)
@@ -494,7 +472,11 @@
 
 PlaylistItem*  PlaylistManager::GetCurrentItem()
 {
+    if( m_current == kInvalidIndex )
+      return NULL;
+
     PlaylistItem* result = NULL;
+
     m_mutex.Acquire();
     
     if(m_masterList.size())
@@ -1669,21 +1651,17 @@
         else
             stable_sort(m_activeList->begin(), m_activeList->end(), not2(PlaylistItemSort(key)));
     
-        m_sortKey = key;
-        m_sortType = type;
-
-        result = kError_NoErr;
     }
     else if(key == kPlaylistSortKey_Random)
     {
         ShuffleIt(m_activeList);
-        
-        m_sortKey = key;
-        m_sortType = type;
-
-        result = kError_NoErr;
     }
 
+    m_sortKey = key;
+    m_sortType = type;
+    
+    result = kError_NoErr;
+
     if(IsntError(result))
     {
         if(kPlaylistKey_MasterPlaylist == GetActivePlaylist() && currentItem)