3.9

1 files changed, 195 insertions, 0 deletions

diff --git a/shared/file_io.cpp b/shared/file_io.cpp
new file mode 100644
index 00000000..345234fd
--- /dev/null
+++ b/shared/file_io.cpp
@@ -0,0 +1,195 @@
+// **************************************************************************
+// * This file is part of the FreeFileSync project. It is distributed under *
+// * GNU General Public License: http://www.gnu.org/licenses/gpl.html       *
+// * Copyright (C) 2008-2010 ZenJu (zhnmju123 AT gmx.de)                    *
+// **************************************************************************
+//
+#include "file_io.h"
+#include <wx/intl.h>
+#include "string_conv.h"
+#include "system_func.h"
+
+#ifdef FFS_WIN
+#include "long_path_prefix.h"
+#elif defined FFS_LINUX
+#include <errno.h>
+#endif
+
+using namespace ffs3;
+
+
+FileInput::FileInput(const Zstring& filename)  : //throw FileError()
+#ifdef FFS_WIN
+    eofReached(false),
+#endif
+    filename_(filename)
+{
+#ifdef FFS_WIN
+    fileHandle = ::CreateFile(ffs3::applyLongPathPrefix(filename).c_str(),
+                              GENERIC_READ,
+                              FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, //all shared modes are required to read files that are open in other applications
+                              NULL,
+                              OPEN_EXISTING,
+                              FILE_FLAG_SEQUENTIAL_SCAN,
+                              /* possible values: (Reference http://msdn.microsoft.com/en-us/library/aa363858(VS.85).aspx#caching_behavior)
+                                FILE_FLAG_NO_BUFFERING
+                                FILE_FLAG_RANDOM_ACCESS
+                                FILE_FLAG_SEQUENTIAL_SCAN
+
+                                tests on Win7 x64 show that FILE_FLAG_SEQUENTIAL_SCAN provides best performance for binary comparison in all cases:
+                                - comparing different physical disks (DVD <-> HDD and HDD <-> HDD)
+                                - even on same physical disk! (HDD <-> HDD)
+                                - independent from client buffer size!
+
+                                tests on XP show that FILE_FLAG_SEQUENTIAL_SCAN provides best performance for binary comparison when
+                                - comparing different physical disks (DVD <-> HDD)
+
+                                while FILE_FLAG_RANDOM_ACCESS offers best performance for
+                                - same physical disk (HDD <-> HDD)
+
+                              Problem: bad XP implementation of prefetch makes flag FILE_FLAG_SEQUENTIAL_SCAN effectively load two files at once from one drive
+                              swapping every 64 kB (or similar). File access times explode!
+                              => For XP it is critical to use FILE_FLAG_RANDOM_ACCESS (to disable prefetch) if reading two files on same disk and
+                              FILE_FLAG_SEQUENTIAL_SCAN when reading from different disk (e.g. massive performance improvement compared to random access for DVD <-> HDD!)
+                              => there is no compromise that satisfies all cases! (on XP)
+
+                              for FFS most comparisons are probably between different disks => let's use FILE_FLAG_SEQUENTIAL_SCAN
+                               */
+                              NULL);
+    if (fileHandle == INVALID_HANDLE_VALUE)
+    {
+        const DWORD lastError = ::GetLastError();
+        const wxString& errorMessage = wxString(_("Error opening file:")) + wxT("\n\"") + zToWx(filename_) + wxT("\"") + wxT("\n\n") + ffs3::getLastErrorFormatted(lastError);
+        if (lastError == ERROR_FILE_NOT_FOUND)
+            throw ErrorNotExisting(errorMessage);
+        else
+            throw FileError(errorMessage);
+    }
+#elif defined FFS_LINUX
+    fileHandle = ::fopen(filename.c_str(), "rb,type=record,noseek"); //utilize UTF-8 filename
+    if (fileHandle == NULL)
+    {
+        const int lastError = errno;
+        const wxString& errorMessage = wxString(_("Error opening file:")) + wxT("\n\"") + zToWx(filename_) + wxT("\"") + wxT("\n\n") + ffs3::getLastErrorFormatted(lastError);
+        if (lastError == ENOENT)
+            throw ErrorNotExisting(errorMessage);
+        else
+            throw FileError(errorMessage);
+    }
+#endif
+}
+
+
+FileInput::~FileInput()
+{
+#ifdef FFS_WIN
+    ::CloseHandle(fileHandle);
+#elif defined FFS_LINUX
+    ::fclose(fileHandle); //NEVER allow passing NULL to fclose! -> crash!; fileHandle != NULL in this context!
+#endif
+}
+
+
+size_t FileInput::read(void* buffer, size_t bytesToRead) //returns actual number of bytes read; throw FileError()
+{
+#ifdef FFS_WIN
+    DWORD bytesRead = 0;
+
+    if (!::ReadFile(
+                fileHandle,    //__in         HANDLE hFile,
+                buffer,        //__out        LPVOID lpBuffer,
+                static_cast<DWORD>(bytesToRead), //__in         DWORD nNumberOfBytesToRead,
+                &bytesRead,    //__out_opt    LPDWORD lpNumberOfBytesRead,
+                NULL)          //__inout_opt  LPOVERLAPPED lpOverlapped
+            || bytesRead > bytesToRead) //must be fulfilled
+        throw FileError(wxString(_("Error reading file:")) + wxT("\n\"") + zToWx(filename_) + wxT("\"") +
+                        wxT("\n\n") + ffs3::getLastErrorFormatted());
+
+    if (bytesRead < bytesToRead)
+        eofReached = true;
+
+    return bytesRead;
+#elif defined FFS_LINUX
+    const size_t bytesRead = ::fread(buffer, 1, bytesToRead, fileHandle);
+    if (::ferror(fileHandle) != 0)
+        throw FileError(wxString(_("Error reading file:")) + wxT("\n\"") + zToWx(filename_) + wxT("\"") +
+                        wxT("\n\n") + ffs3::getLastErrorFormatted());
+    return bytesRead;
+#endif
+}
+
+
+bool FileInput::eof() //end of file reached
+{
+#ifdef FFS_WIN
+    return eofReached;
+#elif defined FFS_LINUX
+    return ::feof(fileHandle) != 0;
+#endif
+}
+
+
+FileOutput::FileOutput(const Zstring& filename) : //throw FileError()
+    filename_(filename)
+{
+#ifdef FFS_WIN
+    fileHandle = ::CreateFile(ffs3::applyLongPathPrefix(filename).c_str(),
+                              GENERIC_WRITE,
+                              FILE_SHARE_READ,
+                              NULL,
+                              CREATE_ALWAYS,
+                              FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN,
+                              NULL);
+    if (fileHandle == INVALID_HANDLE_VALUE)
+        throw FileError(wxString(_("Error writing file:")) + wxT("\n\"") + zToWx(filename_) + wxT("\"") +
+                        wxT("\n\n") + ffs3::getLastErrorFormatted());
+#elif defined FFS_LINUX
+    fileHandle = ::fopen(filename.c_str(), "wb,type=record,noseek"); //utilize UTF-8 filename
+    if (!fileHandle)
+        throw FileError(wxString(_("Error writing file:")) + wxT("\n\"") + zToWx(filename_) + wxT("\"") +
+                        wxT("\n\n") + ffs3::getLastErrorFormatted());
+#endif
+}
+
+
+FileOutput::~FileOutput()
+{
+    close(); //may be called more than once
+}
+
+
+void FileOutput::write(const void* buffer, size_t bytesToWrite) //throw FileError()
+{
+#ifdef FFS_WIN
+    DWORD bytesWritten = 0;
+
+    if (!::WriteFile(
+                fileHandle,    //__in         HANDLE hFile,
+                buffer,        //__out        LPVOID lpBuffer,
+                static_cast<DWORD>(bytesToWrite),  //__in         DWORD nNumberOfBytesToRead,
+                &bytesWritten, //__out_opt    LPDWORD lpNumberOfBytesWritten,
+                NULL)          //__inout_opt  LPOVERLAPPED lpOverlapped
+            || bytesWritten != bytesToWrite) //must be fulfilled for synchronous writes!
+        throw FileError(wxString(_("Error writing file:")) + wxT("\n\"") + zToWx(filename_) + wxT("\"") +
+                        wxT("\n\n") + ffs3::getLastErrorFormatted() + wxT(" (w)")); //w -> distinguish from fopen error message!
+#elif defined FFS_LINUX
+    const size_t bytesWritten = ::fwrite(buffer, 1, bytesToWrite, fileHandle);
+    if (::ferror(fileHandle) != 0 || bytesWritten != bytesToWrite)
+        throw FileError(wxString(_("Error writing file:")) + wxT("\n\"") + zToWx(filename_) + wxT("\"") +
+                        wxT("\n\n") + ffs3::getLastErrorFormatted() + wxT(" (w)")); //w -> distinguish from fopen error message!
+#endif
+}
+
+
+void FileOutput::close() //close file stream
+{
+    if (fileHandle != NULL) //NEVER allow passing NULL to fclose! -> crash!
+    {
+#ifdef FFS_WIN
+        ::CloseHandle(fileHandle);
+#elif defined FFS_LINUX
+        ::fclose(fileHandle);
+#endif
+        fileHandle = NULL;
+    }
+}