llvm-project/libcxx/include/__std_stream

363 lines
10 KiB
C++

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___STD_STREAM
#define _LIBCPP___STD_STREAM
#include <__config>
#include <ostream>
#include <istream>
#include <__locale>
#include <cstdio>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
_LIBCPP_BEGIN_NAMESPACE_STD
static const int __limit = 8;
// __stdinbuf
template <class _CharT>
class _LIBCPP_HIDDEN __stdinbuf
: public basic_streambuf<_CharT, char_traits<_CharT> >
{
public:
typedef _CharT char_type;
typedef char_traits<char_type> traits_type;
typedef typename traits_type::int_type int_type;
typedef typename traits_type::pos_type pos_type;
typedef typename traits_type::off_type off_type;
typedef typename traits_type::state_type state_type;
__stdinbuf(FILE* __fp, state_type* __st);
protected:
virtual int_type underflow();
virtual int_type uflow();
virtual int_type pbackfail(int_type __c = traits_type::eof());
virtual void imbue(const locale& __loc);
private:
FILE* __file_;
const codecvt<char_type, char, state_type>* __cv_;
state_type* __st_;
int __encoding_;
int_type __last_consumed_;
bool __last_consumed_is_next_;
bool __always_noconv_;
__stdinbuf(const __stdinbuf&);
__stdinbuf& operator=(const __stdinbuf&);
int_type __getchar(bool __consume);
};
template <class _CharT>
__stdinbuf<_CharT>::__stdinbuf(FILE* __fp, state_type* __st)
: __file_(__fp),
__st_(__st),
__last_consumed_(traits_type::eof()),
__last_consumed_is_next_(false)
{
imbue(this->getloc());
}
template <class _CharT>
void
__stdinbuf<_CharT>::imbue(const locale& __loc)
{
__cv_ = &use_facet<codecvt<char_type, char, state_type> >(__loc);
__encoding_ = __cv_->encoding();
__always_noconv_ = __cv_->always_noconv();
if (__encoding_ > __limit)
__throw_runtime_error("unsupported locale for standard input");
}
template <class _CharT>
typename __stdinbuf<_CharT>::int_type
__stdinbuf<_CharT>::underflow()
{
return __getchar(false);
}
template <class _CharT>
typename __stdinbuf<_CharT>::int_type
__stdinbuf<_CharT>::uflow()
{
return __getchar(true);
}
template <class _CharT>
typename __stdinbuf<_CharT>::int_type
__stdinbuf<_CharT>::__getchar(bool __consume)
{
if (__last_consumed_is_next_)
{
int_type __result = __last_consumed_;
if (__consume)
{
__last_consumed_ = traits_type::eof();
__last_consumed_is_next_ = false;
}
return __result;
}
char __extbuf[__limit];
int __nread = _VSTD::max(1, __encoding_);
for (int __i = 0; __i < __nread; ++__i)
{
int __c = getc(__file_);
if (__c == EOF)
return traits_type::eof();
__extbuf[__i] = static_cast<char>(__c);
}
char_type __1buf;
if (__always_noconv_)
__1buf = static_cast<char_type>(__extbuf[0]);
else
{
const char* __enxt;
char_type* __inxt;
codecvt_base::result __r;
do
{
state_type __sv_st = *__st_;
__r = __cv_->in(*__st_, __extbuf, __extbuf + __nread, __enxt,
&__1buf, &__1buf + 1, __inxt);
switch (__r)
{
case _VSTD::codecvt_base::ok:
break;
case codecvt_base::partial:
*__st_ = __sv_st;
if (__nread == sizeof(__extbuf))
return traits_type::eof();
{
int __c = getc(__file_);
if (__c == EOF)
return traits_type::eof();
__extbuf[__nread] = static_cast<char>(__c);
}
++__nread;
break;
case codecvt_base::error:
return traits_type::eof();
case _VSTD::codecvt_base::noconv:
__1buf = static_cast<char_type>(__extbuf[0]);
break;
}
} while (__r == _VSTD::codecvt_base::partial);
}
if (!__consume)
{
for (int __i = __nread; __i > 0;)
{
if (ungetc(traits_type::to_int_type(__extbuf[--__i]), __file_) == EOF)
return traits_type::eof();
}
}
else
__last_consumed_ = traits_type::to_int_type(__1buf);
return traits_type::to_int_type(__1buf);
}
template <class _CharT>
typename __stdinbuf<_CharT>::int_type
__stdinbuf<_CharT>::pbackfail(int_type __c)
{
if (traits_type::eq_int_type(__c, traits_type::eof()))
{
if (!__last_consumed_is_next_)
{
__c = __last_consumed_;
__last_consumed_is_next_ = !traits_type::eq_int_type(__last_consumed_,
traits_type::eof());
}
return __c;
}
if (__last_consumed_is_next_)
{
char __extbuf[__limit];
char* __enxt;
const char_type __ci = traits_type::to_char_type(__last_consumed_);
const char_type* __inxt;
switch (__cv_->out(*__st_, &__ci, &__ci + 1, __inxt,
__extbuf, __extbuf + sizeof(__extbuf), __enxt))
{
case _VSTD::codecvt_base::ok:
break;
case _VSTD::codecvt_base::noconv:
__extbuf[0] = static_cast<char>(__last_consumed_);
__enxt = __extbuf + 1;
break;
case codecvt_base::partial:
case codecvt_base::error:
return traits_type::eof();
}
while (__enxt > __extbuf)
if (ungetc(*--__enxt, __file_) == EOF)
return traits_type::eof();
}
__last_consumed_ = __c;
__last_consumed_is_next_ = true;
return __c;
}
// __stdoutbuf
template <class _CharT>
class _LIBCPP_HIDDEN __stdoutbuf
: public basic_streambuf<_CharT, char_traits<_CharT> >
{
public:
typedef _CharT char_type;
typedef char_traits<char_type> traits_type;
typedef typename traits_type::int_type int_type;
typedef typename traits_type::pos_type pos_type;
typedef typename traits_type::off_type off_type;
typedef typename traits_type::state_type state_type;
__stdoutbuf(FILE* __fp, state_type* __st);
protected:
virtual int_type overflow (int_type __c = traits_type::eof());
virtual streamsize xsputn(const char_type* __s, streamsize __n);
virtual int sync();
virtual void imbue(const locale& __loc);
private:
FILE* __file_;
const codecvt<char_type, char, state_type>* __cv_;
state_type* __st_;
bool __always_noconv_;
__stdoutbuf(const __stdoutbuf&);
__stdoutbuf& operator=(const __stdoutbuf&);
};
template <class _CharT>
__stdoutbuf<_CharT>::__stdoutbuf(FILE* __fp, state_type* __st)
: __file_(__fp),
__cv_(&use_facet<codecvt<char_type, char, state_type> >(this->getloc())),
__st_(__st),
__always_noconv_(__cv_->always_noconv())
{
}
template <class _CharT>
typename __stdoutbuf<_CharT>::int_type
__stdoutbuf<_CharT>::overflow(int_type __c)
{
char __extbuf[__limit];
char_type __1buf;
if (!traits_type::eq_int_type(__c, traits_type::eof()))
{
__1buf = traits_type::to_char_type(__c);
if (__always_noconv_)
{
if (fwrite(&__1buf, sizeof(char_type), 1, __file_) != 1)
return traits_type::eof();
}
else
{
char* __extbe = __extbuf;
codecvt_base::result __r;
char_type* pbase = &__1buf;
char_type* pptr = pbase + 1;
do
{
const char_type* __e;
__r = __cv_->out(*__st_, pbase, pptr, __e,
__extbuf,
__extbuf + sizeof(__extbuf),
__extbe);
if (__e == pbase)
return traits_type::eof();
if (__r == codecvt_base::noconv)
{
if (fwrite(pbase, 1, 1, __file_) != 1)
return traits_type::eof();
}
else if (__r == codecvt_base::ok || __r == codecvt_base::partial)
{
size_t __nmemb = static_cast<size_t>(__extbe - __extbuf);
if (fwrite(__extbuf, 1, __nmemb, __file_) != __nmemb)
return traits_type::eof();
if (__r == codecvt_base::partial)
{
pbase = const_cast<char_type*>(__e);
}
}
else
return traits_type::eof();
} while (__r == codecvt_base::partial);
}
}
return traits_type::not_eof(__c);
}
template <class _CharT>
streamsize
__stdoutbuf<_CharT>::xsputn(const char_type* __s, streamsize __n)
{
if (__always_noconv_)
return fwrite(__s, sizeof(char_type), __n, __file_);
streamsize __i = 0;
for (; __i < __n; ++__i, ++__s)
if (overflow(traits_type::to_int_type(*__s)) == traits_type::eof())
break;
return __i;
}
template <class _CharT>
int
__stdoutbuf<_CharT>::sync()
{
char __extbuf[__limit];
codecvt_base::result __r;
do
{
char* __extbe;
__r = __cv_->unshift(*__st_, __extbuf,
__extbuf + sizeof(__extbuf),
__extbe);
size_t __nmemb = static_cast<size_t>(__extbe - __extbuf);
if (fwrite(__extbuf, 1, __nmemb, __file_) != __nmemb)
return -1;
} while (__r == codecvt_base::partial);
if (__r == codecvt_base::error)
return -1;
if (fflush(__file_))
return -1;
return 0;
}
template <class _CharT>
void
__stdoutbuf<_CharT>::imbue(const locale& __loc)
{
sync();
__cv_ = &use_facet<codecvt<char_type, char, state_type> >(__loc);
__always_noconv_ = __cv_->always_noconv();
}
_LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
#endif // _LIBCPP___STD_STREAM