- getline(ifs, str);
- string const stamp = str.substr(0, 2);
- if (firstLine && str.size() >= 2) {
- // at first we check for a zipped file, because this
- // information is saved in the first bytes of the file!
- // also some graphic formats which save the information
- // in the first line, too.
- if (prefixIs(str, gzipStamp)) {
- format = "gzip";
-
- } else if (stamp == zipStamp) {
- format = "zip";
-
- } else if (stamp == compressStamp) {
- format = "compress";
-
- // the graphics part
- } else if (stamp == "BM") {
- format = "bmp";
-
- } else if (stamp == "\001\332") {
- format = "sgi";
-
- // PBM family
- // Don't need to use str.at(0), str.at(1) because
- // we already know that str.size() >= 2
- } else if (str[0] == 'P') {
- switch (str[1]) {
- case '1':
- case '4':
- format = "pbm";
- break;
- case '2':
- case '5':
- format = "pgm";
- break;
- case '3':
- case '6':
- format = "ppm";
- }
- break;
-
- } else if ((stamp == "II") || (stamp == "MM")) {
- format = "tiff";
-
- } else if (prefixIs(str,"%TGIF")) {
- format = "tgif";
-
- } else if (prefixIs(str,"#FIG")) {
- format = "fig";
-
- } else if (prefixIs(str,"GIF")) {
- format = "gif";
-
- } else if (str.size() > 3) {
- int const c = ((str[0] << 24) & (str[1] << 16) &
- (str[2] << 8) & str[3]);
- if (c == 105) {
- format = "xwd";
- }
- }
-
- firstLine = false;
- }
+ istreambuf_iterator<char> beg(ifs);
+ istreambuf_iterator<char> end;
+ boost::crc_32_type crc;
+ crc = for_each(beg, end, crc);
+ result = crc.checksum();
+ return result;
+}
+
+unsigned long FileName::checksum() const
+{
+ unsigned long result = 0;
+
+ if (!exists()) {
+ //LYXERR0("File \"" << absFileName() << "\" does not exist!");
+ return result;
+ }
+ // a directory may be passed here so we need to test it. (bug 3622)
+ if (isDirectory()) {
+ LYXERR0('"' << absFileName() << "\" is a directory!");
+ return result;
+ }
+
+ // This is used in the debug output at the end of the method.
+ static QTime t;
+ if (lyxerr.debugging(Debug::FILES))
+ t.restart();
+
+#if QT_VERSION >= 0x999999
+ // First version of checksum uses Qt4.4 mmap support.
+ // FIXME: This code is not ready with Qt4.4.2,
+ // see http://www.lyx.org/trac/ticket/5293
+ // 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 result;
+ qint64 size = fi.size();
+ uchar * ubeg = qf.map(0, size);
+ uchar * uend = ubeg + size;
+ boost::crc_32_type ucrc;
+ ucrc.process_block(ubeg, uend);
+ qf.unmap(ubeg);
+ qf.close();
+ result = ucrc.checksum();
+
+#else // QT_VERSION
+
+ string const encoded = toSafeFilesystemEncoding();
+ char const * file = encoded.c_str();
+
+ #ifdef SUM_WITH_MMAP
+ //LYXERR(Debug::FILES, "using mmap (lightning fast)");
+
+ int fd = open(file, O_RDONLY);
+ if (!fd)
+ return result;
+
+ struct stat info;
+ if (fstat(fd, &info)){
+ // fstat fails on samba shares (bug 5891)
+ close(fd);
+ return checksum_ifstream_fallback(file);
+ }
+
+ void * mm = mmap(0, info.st_size, PROT_READ,
+ MAP_PRIVATE, fd, 0);
+ // Some platforms have the wrong type for MAP_FAILED (compaq cxx).
+ if (mm == reinterpret_cast<void*>(MAP_FAILED)) {
+ close(fd);
+ return result;
+ }
+
+ char * beg = static_cast<char*>(mm);
+ char * end = beg + info.st_size;