move sum() to FileName::private::checksum() and add a new method using Qt4.4 mmap...

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@26590 a592a061-630c-0410-9148-cb99ea01b6c8

diff --git a/src/support/FileName.cpp b/src/support/FileName.cpp
index 4234a840e563a68c98f1b95110f9d029bd3c5565..21e66b0fb2082637b82ee862142368e3fd650c52 100644 (file)
--- a/src/support/FileName.cpp
+++ b/src/support/FileName.cpp
@@ -73,8 +73,7 @@ extern "C" int mkstemp(char *);
 # endif
 #endif
 
-// Various implementations of sum(), depending on what methods
-// are available. Order is faster to slowest.
+// Three implementations of checksum(), depending on having mmap support or not.
 #if defined(HAVE_MMAP) && defined(HAVE_MUNMAP)
 #define SUM_WITH_MMAP
 #include <sys/mman.h>
@@ -94,10 +93,65 @@ template struct boost::detail::crc_table_t<32, 0x04C11DB7, true>;
 namespace lyx {
 namespace support {
 
-static unsigned long sum(char const * file)
+/////////////////////////////////////////////////////////////////////
+//
+// FileName::Private
+//
+/////////////////////////////////////////////////////////////////////
+
+struct FileName::Private
 {
+       Private() {}
+
+       Private(string const & abs_filename) : fi(toqstr(abs_filename))
+       {
+               fi.setCaching(fi.exists() ? true : false);
+       }
+       ///
+       inline void refresh() 
+       {
+// There seems to be a bug in Qt >= 4.2.0, at least, that causes problems with
+// QFileInfo::refresh() on *nix. So we recreate the object in that case.
+// FIXME: When Trolltech fixes the bug, we will have to replace 0x999999 below
+// with the actual working minimum version.
+#if defined(_WIN32) || (QT_VERSION >= 0x999999)
+               fi.refresh();
+#else
+               fi = QFileInfo(fi.absoluteFilePath());
+#endif
+       }
+
+       unsigned long checksum();
+
+       ///
+       QFileInfo fi;
+};
+
+unsigned long FileName::Private::checksum()
+{
+#if QT_VERSION >= 0x040400
+       // First version of checksum uses Qt4.4 mmap support.
+       // FIXME: should we check if the MapExtension extension is supported?
+       // see QAbstractFileEngine::supportsExtension() and 
+       // QAbstractFileEngine::MapExtension)
+       QFile qf(fi.filePath());
+       if (!qf.open(QIODevice::ReadOnly))
+               return 0;
+       qint64 size = fi.size();
+       uchar * ubeg = qf.map(0, size);
+       uchar * uend = ubeg + size;
+       boost::crc_32_type ucrc;
+       ucrc.process_block(ubeg, uend);
+       return ucrc.checksum();
+#endif
+
+       //FIXME: This doesn't work on Windows for non ascii file names. Provided that
+       // Windows package uses Qt4.4, this isn't a problem.
+       QByteArray const encoded = QFile::encodeName(fi.absoluteFilePath());
+       char const * file = encoded.constData();
+
 #ifdef SUM_WITH_MMAP
-       //LYXERR(Debug::FILES, "lyx::sum() using mmap (lightning fast)");
+       //LYXERR(Debug::FILES, "using mmap (lightning fast)");
 
        int fd = open(file, O_RDONLY);
        if (!fd)
@@ -142,38 +196,6 @@ static unsigned long sum(char const * file)
 #endif // SUM_WITH_MMAP
 }
 
-
-/////////////////////////////////////////////////////////////////////
-//
-// FileName::Private
-//
-/////////////////////////////////////////////////////////////////////
-
-struct FileName::Private
-{
-       Private() {}
-
-       Private(string const & abs_filename) : fi(toqstr(abs_filename))
-       {
-               fi.setCaching(fi.exists() ? true : false);
-       }
-       ///
-       inline void refresh() 
-       {
-// There seems to be a bug in Qt >= 4.2.0, at least, that causes problems with
-// QFileInfo::refresh() on *nix. So we recreate the object in that case.
-// FIXME: When Trolltech fixes the bug, we will have to replace 0x999999 below
-// with the actual working minimum version.
-#if defined(_WIN32) || (QT_VERSION >= 0x999999)
-               fi.refresh();
-#else
-               fi = QFileInfo(fi.absoluteFilePath());
-#endif
-       }
-       ///
-       QFileInfo fi;
-};
-
 /////////////////////////////////////////////////////////////////////
 //
 // FileName
@@ -505,13 +527,13 @@ unsigned long FileName::checksum() const
                return 0;
        }
        if (!lyxerr.debugging(Debug::FILES))
-               return sum(absFilename().c_str());
+               return d->checksum();
 
        QTime t;
        t.start();
-       unsigned long r = sum(absFilename().c_str());
-       lyxerr << "Checksumming \"" << absFilename() << "\" lasted "
-               << t.elapsed() << " ms." << endl;
+       unsigned long r = d->checksum();
+       lyxerr << "Checksumming \"" << absFilename() << "\" "
+               << r << " lasted " << t.elapsed() << " ms." << endl;
        return r;
 }