Added a method MemoryBlock::replaceWith(). Changed FileInputStream to avoid cacheing the length of the file.

modules/juce_core/files/juce_FileInputStream.cpp

@@ -30,7 +30,6 @@ FileInputStream::FileInputStream (const File& f)
     : file (f),
       fileHandle (nullptr),
       currentPosition (0),
-      totalSize (0),
       status (Result::ok()),
       needToSeek (true)
 {
@@ -45,7 +44,7 @@ FileInputStream::~FileInputStream()
 //==============================================================================
 int64 FileInputStream::getTotalLength()
 {
-    return totalSize;
+    return file.getSize();
 }
 
 int FileInputStream::read (void* buffer, int bytesToRead)
@@ -69,7 +68,7 @@ int FileInputStream::read (void* buffer, int bytesToRead)
 
 bool FileInputStream::isExhausted()
 {
-    return currentPosition >= totalSize;
+    return currentPosition >= getTotalLength();
 }
 
 int64 FileInputStream::getPosition()
@@ -80,10 +79,14 @@ int64 FileInputStream::getPosition()
 bool FileInputStream::setPosition (int64 pos)
 {
     jassert (openedOk());
-    pos = jlimit ((int64) 0, totalSize, pos);
 
-    needToSeek |= (currentPosition != pos);
-    currentPosition = pos;
+    if (pos != currentPosition)
+    {
+        pos = jlimit ((int64) 0, getTotalLength(), pos);
+
+        needToSeek |= (currentPosition != pos);
+        currentPosition = pos;
+    }
 
     return true;
 }

modules/juce_core/files/juce_FileInputStream.h

@@ -82,7 +82,7 @@ private:
     //==============================================================================
     File file;
     void* fileHandle;
-    int64 currentPosition, totalSize;
+    int64 currentPosition;
     Result status;
     bool needToSeek;
 

modules/juce_core/memory/juce_MemoryBlock.cpp

@@ -175,6 +175,16 @@ void MemoryBlock::append (const void* const srcData, const size_t numBytes)
     }
 }
 
+void MemoryBlock::replaceWith (const void* const srcData, const size_t numBytes)
+{
+    if (numBytes > 0)
+    {
+        jassert (srcData != nullptr); // this must not be null!
+        setSize (numBytes);
+        memcpy (data, srcData, numBytes);
+    }
+}
+
 void MemoryBlock::insert (const void* const srcData, const size_t numBytes, size_t insertPosition)
 {
     if (numBytes > 0)

modules/juce_core/memory/juce_MemoryBlock.h

@@ -150,6 +150,11 @@ public:
     */
     void append (const void* data, size_t numBytes);
 
+    /** Resizes this block to the given size and fills its contents from the supplied buffer.
+        The data pointer must not be null.
+    */
+    void replaceWith (const void* data, size_t numBytes);
+
     /** Inserts some data into the block.
         The dataToInsert pointer must not be null. This block's size will be increased accordingly.
         If the insert position lies outside the valid range of the block, it will be clipped to

modules/juce_core/native/juce_posix_SharedCode.h

@@ -413,8 +413,6 @@ int64 juce_fileSetPosition (void* handle, int64 pos)
 
 void FileInputStream::openHandle()
 {
-    totalSize = file.getSize();
-
     const int f = open (file.getFullPathName().toUTF8(), O_RDONLY, 00644);
 
     if (f != -1)

modules/juce_core/native/juce_win32_Files.cpp

@@ -222,8 +222,6 @@ int64 juce_fileSetPosition (void* handle, int64 pos)
 
 void FileInputStream::openHandle()
 {
-    totalSize = file.getSize();
-
     HANDLE h = CreateFile (file.getFullPathName().toWideCharPointer(), GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE, 0,
                            OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN, 0);
 

modules/juce_core/streams/juce_OutputStream.cpp

@@ -241,7 +241,7 @@ int OutputStream::writeFromInputStream (InputStream& source, int64 numBytesToWri
 
     int numWritten = 0;
 
-    while (numBytesToWrite > 0 && ! source.isExhausted())
+    while (numBytesToWrite > 0)
     {
         char buffer [8192];
         const int num = source.read (buffer, (int) jmin (numBytesToWrite, (int64) sizeof (buffer)));