You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
56 lines
1.4 KiB
56 lines
1.4 KiB
/* Distributed under the OSI-approved BSD 3-Clause License. See accompanying
|
|
file Copyright.txt or https://cmake.org/licensing#kwsys for details. */
|
|
#include "kwsysPrivate.h"
|
|
#include KWSYS_HEADER(FStream.hxx)
|
|
|
|
// Work-around CMake dependency scanning limitation. This must
|
|
// duplicate the above list of headers.
|
|
#if 0
|
|
# include "FStream.hxx.in"
|
|
#endif
|
|
|
|
namespace KWSYS_NAMESPACE {
|
|
namespace FStream {
|
|
|
|
BOM ReadBOM(std::istream& in)
|
|
{
|
|
if (!in.good()) {
|
|
return BOM_None;
|
|
}
|
|
unsigned long orig = in.tellg();
|
|
unsigned char bom[4];
|
|
in.read(reinterpret_cast<char*>(bom), 2);
|
|
if (!in.good()) {
|
|
in.clear();
|
|
in.seekg(orig);
|
|
return BOM_None;
|
|
}
|
|
if (bom[0] == 0xEF && bom[1] == 0xBB) {
|
|
in.read(reinterpret_cast<char*>(bom + 2), 1);
|
|
if (in.good() && bom[2] == 0xBF) {
|
|
return BOM_UTF8;
|
|
}
|
|
} else if (bom[0] == 0xFE && bom[1] == 0xFF) {
|
|
return BOM_UTF16BE;
|
|
} else if (bom[0] == 0x00 && bom[1] == 0x00) {
|
|
in.read(reinterpret_cast<char*>(bom + 2), 2);
|
|
if (in.good() && bom[2] == 0xFE && bom[3] == 0xFF) {
|
|
return BOM_UTF32BE;
|
|
}
|
|
} else if (bom[0] == 0xFF && bom[1] == 0xFE) {
|
|
unsigned long p = in.tellg();
|
|
in.read(reinterpret_cast<char*>(bom + 2), 2);
|
|
if (in.good() && bom[2] == 0x00 && bom[3] == 0x00) {
|
|
return BOM_UTF32LE;
|
|
}
|
|
in.seekg(p);
|
|
return BOM_UTF16LE;
|
|
}
|
|
in.clear();
|
|
in.seekg(orig);
|
|
return BOM_None;
|
|
}
|
|
|
|
} // FStream namespace
|
|
} // KWSYS_NAMESPACE
|