[Kst] branches/work/kst/portto4/kst/src/datasources/ascii

[Peter Kümmel]

SVN commit 1319739 by kuemmel:

QVarLenghArray simply asserts when not enough memory is available

so we have to check it by our self.

 M  +10 -0     asciisource.cpp  
 M  +21 -7     asciisource.h  


--- branches/work/kst/portto4/kst/src/datasources/ascii/asciisource.cpp #1319738:1319739
@@ -479,6 +479,16 @@
   return -1;
 }
 
+//-------------------------------------------------------------------------------------------
+bool AsciiSource::couldAllocate(int bytes) const
+{
+  void* ptr = qMalloc(bytes);
+  if (ptr) {
+    qFree(ptr);
+    return true;
+  }
+  return false;
+}
 
 //-------------------------------------------------------------------------------------------
 void AsciiSource::clearFileBuffer()
--- branches/work/kst/portto4/kst/src/datasources/ascii/asciisource.h #1319738:1319739
@@ -85,14 +85,18 @@
 #else
 #define KST_PREALLOC 1 * 1024 * 1024
 #endif
+    QVarLengthArray<int, KST_PREALLOC> _rowIndex;
     typedef QVarLengthArray<char, KST_PREALLOC> FileBuffer;
     FileBuffer* _fileBuffer;
     void clearFileBuffer();
+    bool couldAllocate(int bytes) const;
     int _bufferedS;
     int _bufferedN;
     
-    QVarLengthArray<int, KST_PREALLOC> _rowIndex;
+    template<class T>
+    bool resizeBuffer(T& buffer, int bytes);
 
+
     friend class ConfigWidgetAscii;
     mutable AsciiSourceConfig _config;
        
@@ -251,27 +255,37 @@
     friend class DataInterfaceAsciiVector;
 };
 
+template<class T>
+bool AsciiSource::resizeBuffer(T& buffer, int bytes)
+{ 
+  if (!couldAllocate(bytes))
+    return false;
 
+  const int oldSize = buffer.size();
+  buffer.resize(bytes);
+  if (buffer.size() == oldSize)
+      return false;
+  return true;
+}
+
 template<class T>
 int AsciiSource::readFromFile(QFile& file, T& buffer, int start, int bytesToRead, int maximalBytes)
 {    
-  const int oldSize = buffer.size();
   if (maximalBytes == -1) {
-    buffer.resize(bytesToRead + 1);
-    if (buffer.size() == oldSize)
+    if (!resizeBuffer(buffer, bytesToRead + 1))
       return 0;
   } else {
     bytesToRead = qMin(bytesToRead, maximalBytes);
     if (buffer.size() <= bytesToRead) {
-      buffer.resize(bytesToRead + 1);
-      if (buffer.size() == oldSize)
+      if (!resizeBuffer(buffer, bytesToRead + 1))
         return 0;
     }
   }
   file.seek(start); // expensive?
   int bytesRead = file.read(buffer.data(), bytesToRead);
   if (buffer.size() <= bytesRead) {
-    buffer.resize(bytesRead + 1);
+    if (!resizeBuffer(buffer, bytesToRead + 1))
+      return 0;
   }
   buffer.data()[bytesRead] = '\0';  
   return bytesRead;