Ticket #8094: file_preallocation_v2.patch

src/engine/file.cpp

@@ -79 +79 @@
     return ret;
 }
 
+bool CFile::Truncate()
+{
+    return !!SetEndOfFile(hFile_);
+}
+
 ssize_t CFile::Read(void *buf, size_t count)
 {
     ssize_t ret = -1;
@@ -171 +176 @@
     return ret;
 }
 
+bool CFile::Truncate()
+{
+    bool ret = false;
+
+    auto length = lseek(fd_, 0, SEEK_CUR);
+    if (length != static_cast<off_t>(-1)) {
+        do {
+            ret = !ftruncate(fd_, length);
+        } while (!ret && (errno == EAGAIN || errno == EINTR));
+    }
+
+    return ret;
+}
+
 ssize_t CFile::Read(void *buf, size_t count)
 {
     ssize_t ret;

src/engine/file.h

@@ -48 +48 @@
     // On failure, the new position in the file is undefined.
     wxFileOffset Seek(wxFileOffset offset, seekMode m);
 
+    // Truncate the file to the current position of the file pointer.
+    bool Truncate();
+
     // Returns number of bytes read or -1 on error
     ssize_t Read(void *buf, size_t count);
 

src/engine/ftpcontrolsocket.cpp

@@ -2601 +2601 @@
                     pData->resumeOffset = 0;
 
                 InitTransferStatus(pData->remoteFileSize, startOffset, false);
+
+                // Try to preallocate the file in order to reduce fragmentation
+                wxFileOffset sizeToPreallocate = pData->remoteFileSize - startOffset;
+                if (sizeToPreallocate > 0)
+                {
+                    LogMessage(MessageType::Debug_Info, _T("Preallocating %") wxFileOffsetFmtSpec _T("d bytes for the file \"%s\""), sizeToPreallocate, pData->localFile);
+                    wxFileOffset oldPos = pFile->Seek(0, CFile::current);
+                    if (pFile->Seek(sizeToPreallocate, CFile::end) == pData->remoteFileSize)
+                    {
+                        if (!pFile->Truncate())
+                            LogMessage(MessageType::Debug_Warning, _T("Impossible to preallocate the file"));
+                    }
+                    pFile->Seek(oldPos, CFile::begin);
+                }
             }
             else {
                 if (!pFile->Open(pData->localFile, CFile::read)) {

src/engine/iothread.cpp

@@ -29 +29 @@
 
 CIOThread::~CIOThread()
 {
-    delete m_pFile;
+    if (m_pFile)
+    {
+        // The file might have been preallocated and the transfer stopped before being completed
+        // so always truncate the file to the actually written size before closing it.
+        if (!m_read)
+            m_pFile->Truncate();
 
+        delete m_pFile;
+    }
+
     for (unsigned int i = 0; i < BUFFERCOUNT; i++)
         delete [] m_buffers[i];
 
@@ -40 +48 @@
 bool CIOThread::Create(CFile* pFile, bool read, bool binary)
 {
     wxASSERT(pFile);
-    delete m_pFile;
+
+    if (m_pFile)
+    {
+        // The file might have been preallocated and the transfer stopped before being completed
+        // so always truncate the file to the actually written size before closing it.
+        if (!m_read)
+            m_pFile->Truncate();
+
+        delete m_pFile;
+    }
+
     m_pFile = pFile;
     m_read = read;
     m_binary = binary;