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#include "config.h"
#include "alfstream.h"
#include "strutils.h"
#ifdef _WIN32
namespace al {
auto filebuf::underflow() -> int_type
{
if(mFile != INVALID_HANDLE_VALUE && gptr() == egptr())
{
// Read in the next chunk of data, and set the pointers on success
DWORD got{};
if(ReadFile(mFile, mBuffer.data(), static_cast<DWORD>(mBuffer.size()), &got, nullptr))
setg(mBuffer.data(), mBuffer.data(), mBuffer.data()+got);
}
if(gptr() == egptr())
return traits_type::eof();
return traits_type::to_int_type(*gptr());
}
auto filebuf::seekoff(off_type offset, std::ios_base::seekdir whence, std::ios_base::openmode mode) -> pos_type
{
if(mFile == INVALID_HANDLE_VALUE || (mode&std::ios_base::out) || !(mode&std::ios_base::in))
return traits_type::eof();
LARGE_INTEGER fpos{};
switch(whence)
{
case std::ios_base::beg:
fpos.QuadPart = offset;
if(!SetFilePointerEx(mFile, fpos, &fpos, FILE_BEGIN))
return traits_type::eof();
break;
case std::ios_base::cur:
// If the offset remains in the current buffer range, just
// update the pointer.
if((offset >= 0 && offset < off_type(egptr()-gptr())) ||
(offset < 0 && -offset <= off_type(gptr()-eback())))
{
// Get the current file offset to report the correct read
// offset.
fpos.QuadPart = 0;
if(!SetFilePointerEx(mFile, fpos, &fpos, FILE_CURRENT))
return traits_type::eof();
setg(eback(), gptr()+offset, egptr());
return fpos.QuadPart - off_type(egptr()-gptr());
}
// Need to offset for the file offset being at egptr() while
// the requested offset is relative to gptr().
offset -= off_type(egptr()-gptr());
fpos.QuadPart = offset;
if(!SetFilePointerEx(mFile, fpos, &fpos, FILE_CURRENT))
return traits_type::eof();
break;
case std::ios_base::end:
fpos.QuadPart = offset;
if(!SetFilePointerEx(mFile, fpos, &fpos, FILE_END))
return traits_type::eof();
break;
default:
return traits_type::eof();
}
setg(nullptr, nullptr, nullptr);
return fpos.QuadPart;
}
auto filebuf::seekpos(pos_type pos, std::ios_base::openmode mode) -> pos_type
{
// Simplified version of seekoff
if(mFile == INVALID_HANDLE_VALUE || (mode&std::ios_base::out) || !(mode&std::ios_base::in))
return traits_type::eof();
LARGE_INTEGER fpos{};
fpos.QuadPart = pos;
if(!SetFilePointerEx(mFile, fpos, &fpos, FILE_BEGIN))
return traits_type::eof();
setg(nullptr, nullptr, nullptr);
return fpos.QuadPart;
}
filebuf::~filebuf()
{
if(mFile != INVALID_HANDLE_VALUE)
CloseHandle(mFile);
mFile = INVALID_HANDLE_VALUE;
}
bool filebuf::open(const wchar_t *filename, std::ios_base::openmode mode)
{
if((mode&std::ios_base::out) || !(mode&std::ios_base::in))
return false;
HANDLE f{CreateFileW(filename, GENERIC_READ, FILE_SHARE_READ, nullptr, OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL, nullptr)};
if(f == INVALID_HANDLE_VALUE) return false;
if(mFile != INVALID_HANDLE_VALUE)
CloseHandle(mFile);
mFile = f;
setg(nullptr, nullptr, nullptr);
return true;
}
bool filebuf::open(const char *filename, std::ios_base::openmode mode)
{
std::wstring wname{utf8_to_wstr(filename)};
return open(wname.c_str(), mode);
}
ifstream::ifstream(const wchar_t *filename, std::ios_base::openmode mode)
: std::istream{nullptr}
{
init(&mStreamBuf);
// Set the failbit if the file failed to open.
if((mode&std::ios_base::out) || !mStreamBuf.open(filename, mode|std::ios_base::in))
clear(failbit);
}
ifstream::ifstream(const char *filename, std::ios_base::openmode mode)
: std::istream{nullptr}
{
init(&mStreamBuf);
// Set the failbit if the file failed to open.
if((mode&std::ios_base::out) || !mStreamBuf.open(filename, mode|std::ios_base::in))
clear(failbit);
}
/* This is only here to ensure the compiler doesn't define an implicit
* destructor, which it tries to automatically inline and subsequently complain
* it can't inline without excessive code growth.
*/
ifstream::~ifstream() { }
} // namespace al
#endif
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