Cleaned up old Windows file rename workaround by using Win API native functions; see issue #430

rtengine/imageio.cc

@@ -2,6 +2,7 @@
  *  This file is part of RawTherapee.
  *
  *  Copyright (c) 2004-2010 Gabor Horvath <hgabor@rawtherapee.com>
+ *  Copyright (c) 2010 Oliver Duis <www.oliverduis.de>
  *
  *  RawTherapee is free software: you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -501,11 +502,7 @@ int ImageIO::loadPPMFromMemory(const char* buffer, int width, int height, bool s
 
 int ImageIO::savePNG  (Glib::ustring fname, int compression, int bps) {
 
-	// create a temporary file name that is opened in parallel by e.g. image viewers whilte RT is still writing
+	FILE *file = safe_g_fopen_WriteBinLock (fname);
-	Glib::ustring tmpFname=fname;
-	tmpFname.append(".tmp");
-
-	FILE *file = safe_g_fopen (tmpFname, "wb");
 
     if (!file) 
       return IMIO_CANNOTREADFILE;
@@ -572,9 +569,6 @@ int ImageIO::savePNG  (Glib::ustring fname, int compression, int bps) {
     delete [] row;
 	fclose (file);
 
-	// Rename temporary filename, practically atomic
-	safe_g_rename(tmpFname,fname);
-
     if (pl) {
         pl->setProgressStr ("Ready.");
         pl->setProgress (1.0);
@@ -592,11 +586,7 @@ int ImageIO::saveJPEG (Glib::ustring fname, int quality) {
 	cinfo.err = jpeg_std_error (&jerr);
 	jpeg_create_compress (&cinfo);
 
-	// create a temporary file name that is opened in parallel by e.g. image viewers whilte RT is still writing
+	FILE *file = safe_g_fopen_WriteBinLock (fname);
-	Glib::ustring tmpFname=fname;
-	tmpFname.append(".tmp");
-
-	FILE *file = safe_g_fopen (tmpFname, "wb");
 
 	if (!file)
           return IMIO_CANNOTREADFILE;
@@ -686,9 +676,6 @@ int ImageIO::saveJPEG (Glib::ustring fname, int quality) {
     delete [] row;
 	fclose (file);
 
-	// Rename temporary filename, practically atomic
-	safe_g_rename(tmpFname,fname);
-
     if (pl) {
         pl->setProgressStr ("Ready.");
         pl->setProgress (1.0);
@@ -709,7 +696,7 @@ int ImageIO::saveTIFF (Glib::ustring fname, int bps, bool uncompressed) {
     unsigned char* linebuffer = new unsigned char[lineWidth];
 // TODO the following needs to be looked into - do we really need two ways to write a Tiff file ?
     if (exifRoot && uncompressed) {
-        FILE *file = safe_g_fopen (fname, "wb");
+        FILE *file = safe_g_fopen_WriteBinLock (fname);
 
         if (!file)
             return IMIO_CANNOTREADFILE;           

rtengine/safegtk.cc

@@ -22,6 +22,10 @@
 #include <safegtk.h>
 #include <guiutils.h>
 #include <glib/gstdio.h>
+#ifdef WIN32
+#include <windows.h>
+#include <fcntl.h>
+#endif
 
 
 Glib::RefPtr<Gdk::Pixbuf> safe_create_from_file(const std::string& filename)
@@ -169,7 +173,7 @@ bool safe_spawn_command_line_async (const Glib::ustring& cmd_utf8)
 #ifdef GLIBMM_EXCEPTIONS_ENABLED        
 		try {
 				cmd = Glib::filename_from_utf8(cmd_utf8);
-				printf ("command line: |%s|\n", cmd.c_str());
+				printf ("command line: %s\n", cmd.c_str());
 				Glib::spawn_command_line_async (cmd.c_str());
 				success = true;
 		} catch (Glib::Exception& ex) {
@@ -179,7 +183,7 @@ bool safe_spawn_command_line_async (const Glib::ustring& cmd_utf8)
 		std::auto_ptr<Glib::Error> error;
 		cmd = Glib::filename_from_utf8(cmd_utf8, error);
 		if (!error.get())	{
-				printf ("command line: |%s|\n", cmd.c_str());
+				printf ("command line: %s\n", cmd.c_str());
 				Glib::spawn_command_line_async (cmd, error);
 			}
 		if (error.get())
@@ -201,7 +205,7 @@ bool safe_spawn_command_line_sync (const Glib::ustring& cmd_utf8)
 		int exitStatus=-1;
         try {
 		    //cmd = Glib::filename_from_utf8(cmd_utf8);
-		    printf ("command line: |%s|\n", cmd_utf8.c_str());
+		    printf ("command line: %s\n", cmd_utf8.c_str());
 
             // if it crashes here on windows, make sure you have the GTK runtime files gspawn-win32-helper*.exe files in RT directory 
 		    Glib::spawn_command_line_sync (cmd_utf8, NULL, NULL, &exitStatus);
@@ -211,6 +215,29 @@ bool safe_spawn_command_line_sync (const Glib::ustring& cmd_utf8)
         return (exitStatus==0);
 }
 
+// Opens a file for binary writing and request exclusive lock (cases were you need "wb" mode plus locking)
+// (Important on Windows to prevent Explorer to crash RT when parallel scanning e.g. a currently written image file)
+FILE * safe_g_fopen_WriteBinLock(const Glib::ustring& fname) {
+    FILE* f=NULL;
+
+#ifdef WIN32
+    // g_fopen just uses _wfopen internally on Windows, does not lock access and has no options to set this
+    // so use a native function to work around this problem
+    wchar_t *wFname = (wchar_t*)g_utf8_to_utf16 (fname.c_str(), -1, NULL, NULL, NULL);
+    HANDLE hFile = CreateFileW(wFname, GENERIC_READ | GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
+    g_free(wFname);
+
+    if (hFile==INVALID_HANDLE_VALUE)
+        f=NULL;
+    else
+        f=_fdopen( _open_osfhandle((intptr_t)hFile, 0) , "wb");
+#else
+    f = safe_g_fopen(fname, "wb");
+#endif
+
+    return f;
+}
+
 FILE * safe_g_fopen(const Glib::ustring& src,const gchar *mode)
 { 
     return g_fopen(src.c_str(),mode); 

rtengine/safegtk.h

@@ -31,6 +31,7 @@ std::string safe_locale_from_utf8 (const Glib::ustring& utf8_str);
 std::string safe_filename_from_utf8 (const Glib::ustring& utf8_str);
 
 FILE * safe_g_fopen(const Glib::ustring& src,const gchar *mode);
+FILE * safe_g_fopen_WriteBinLock(const Glib::ustring& fname);
 bool safe_file_test (const Glib::ustring& filename, Glib::FileTest test);
 int safe_g_remove(const Glib::ustring& filename);
 int safe_g_rename(const Glib::ustring& oldFilename, const Glib::ustring& newFilename);