3 * This file is part of LyX, the document processor.
4 * Licence details can be found in the file COPYING.
6 * \author Lars Gullik Bjønnes
8 * Full author contact details are available in file CREDITS.
13 #include "support/lyxlib.h"
14 #include "support/debug.h"
15 #include "support/FileName.h"
17 #include <boost/crc.hpp>
25 // OK, this is ugly, but it is the only workaround I found to compile
26 // with gcc (any version) on a system which uses a non-GNU toolchain.
27 // The problem is that gcc uses a weak symbol for a particular
28 // instantiation and that the system linker usually does not
29 // understand those weak symbols (seen on HP-UX, tru64, AIX and
30 // others). Thus we force an explicit instanciation of this particular
32 template struct boost::detail::crc_table_t<32, 0x04C11DB7, true>;
34 // Various implementations of lyx::sum(), depending on what methods
35 // are available. Order is faster to slowest.
36 #if defined(HAVE_MMAP) && defined(HAVE_MUNMAP)
38 #ifdef HAVE_SYS_TYPES_H
39 # include <sys/types.h>
41 #ifdef HAVE_SYS_STAT_H
42 # include <sys/stat.h>
55 unsigned long sum(char const * file)
57 //LYXERR(Debug::FILES, "lyx::sum() using mmap (lightning fast)");
59 int fd = open(file, O_RDONLY);
66 void * mm = mmap(0, info.st_size, PROT_READ,
68 // Some platforms have the wrong type for MAP_FAILED (compaq cxx).
69 if (mm == reinterpret_cast<void*>(MAP_FAILED)) {
74 char * beg = static_cast<char*>(mm);
75 char * end = beg + info.st_size;
77 boost::crc_32_type crc;
78 crc.process_block(beg, end);
79 unsigned long result = crc.checksum();
81 munmap(mm, info.st_size);
87 } // namespace support
98 template<typename InputIterator>
100 unsigned long do_crc(InputIterator first, InputIterator last)
102 boost::crc_32_type crc;
103 crc = std::for_each(first, last, crc);
104 return crc.checksum();
114 using std::istreambuf_iterator;
115 using std::istream_iterator;
119 unsigned long sum(char const * file)
121 ifstream ifs(file, ios_base::in | ios_base::binary);
125 #if HAVE_DECL_ISTREAMBUF_ITERATOR
126 //LYXERR(Debug::FILES, "lyx::sum() using istreambuf_iterator (fast)");
127 istreambuf_iterator<char> beg(ifs);
128 istreambuf_iterator<char> end;
130 //LYXERR(Debug::FILES, "lyx::sum() using istream_iterator (slow as a snail)");
131 ifs.unsetf(ios::skipws);
132 istream_iterator<char> beg(ifs);
133 istream_iterator<char> end;
136 return do_crc(beg,end);
139 } // namespace support