/* This file is part of
* ======================================================
- *
+ *
* LyX, The Document Processor
* Copyright 2001 The LyX Team.
*
#include <config.h>
+#include "support/lyxlib.h"
+#include "debug.h"
+
#include <algorithm>
#include <boost/crc.hpp>
-#include "support/lyxlib.h"
-#include "debug.h"
+using std::endl;
// Various implementations of lyx::sum(), depending on what methods
// are available. Order is faster to slowest.
#include <unistd.h>
#include <sys/mman.h>
-using std::ifstream;
-using std::endl;
-using std::for_each;
-using std::istreambuf_iterator;
-using std::istream_iterator;
-using std::ios;
-
unsigned long lyx::sum(string const & file)
{
lyxerr[Debug::FILES] << "lyx::sum() using mmap (lightning fast)"
<< endl;
-
+
int fd = open(file.c_str(), O_RDONLY);
if (!fd)
return 0;
-
+
struct stat info;
fstat(fd, &info);
-
+
void * mm = mmap(0, info.st_size, PROT_READ,
MAP_PRIVATE, fd, 0);
// Some platforms have the wrong type for MAP_FAILED (compaq cxx).
close(fd);
return 0;
}
-
+
char * beg = static_cast<char*>(mm);
char * end = beg + info.st_size;
-
+
boost::crc_32_type crc;
crc.process_block(beg, end);
unsigned long result = crc.checksum();
-
+
munmap(mm, info.st_size);
close(fd);
-
+
return result;
}
#else // No mmap
#include <fstream>
#include <iterator>
+using std::for_each;
+
namespace {
template<typename InputIterator>
} // namespace
#if HAVE_DECL_ISTREAMBUF_ITERATOR
+using std::ifstream;
+using std::istreambuf_iterator;
+
unsigned long lyx::sum(string const & file)
{
lyxerr[Debug::FILES] << "lyx::sum() using istreambuf_iterator (fast)"
ifstream ifs(file.c_str());
if (!ifs) return 0;
-
+
istreambuf_iterator<char> beg(ifs);
istreambuf_iterator<char> end;
-
+
return do_crc(beg,end);
}
#else
+
+using std::istream_iterator;
+using std::ios;
+
unsigned long lyx::sum(string const & file)
{
lyxerr[Debug::FILES]
<< "lyx::sum() using istream_iterator (slow as a snail)"
<< endl;
-
+
ifstream ifs(file.c_str());
if (!ifs) return 0;
-
+
ifs.unsetf(ios::skipws);
istream_iterator<char> beg(ifs);
istream_iterator<char> end;
-
+
return do_crc(beg,end);
}
#endif