libstdc++: __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits > Class Template Reference (original) (raw)

#include <[stdio_sync_filebuf.h](a01226%5Fsource.html)>

Public Types
typedef _CharT	char_type

typedef traits_type::int_type	int_type

typedef traits_type::off_type	off_type

typedef traits_type::pos_type	pos_type

typedef _Traits	traits_type

Public Member Functions
	stdio_sync_filebuf (std::__c_file *__f)

	stdio_sync_filebuf (stdio_sync_filebuf &&__fb) noexcept

std::__c_file *	file ()

locale	getloc () const

streamsize	in_avail ()

stdio_sync_filebuf &	operator= (stdio_sync_filebuf &&__fb) noexcept

locale	pubimbue (const locale &__loc)

int_type	sbumpc ()

int_type	sgetc ()

streamsize	sgetn (char_type *__s, streamsize __n)

int_type	snextc ()

int_type	sputbackc (char_type __c)

int_type	sputc (char_type __c)

streamsize	sputn (const char_type *__s, streamsize __n)

int_type	sungetc ()

void	swap (stdio_sync_filebuf &__fb)

basic_streambuf *	pubsetbuf (char_type *__s, streamsize __n)

pos_type	pubseekoff (off_type __off, ios_base::seekdir __way, ios_base::openmode __mode=ios_base::in\|ios_base::out)

pos_type	pubseekpos (pos_type __sp, ios_base::openmode __mode=ios_base::in\|ios_base::out)

int	pubsync ()

Protected Member Functions
void	__safe_gbump (streamsize __n)

void	__safe_pbump (streamsize __n)

void	gbump (int __n)

virtual void	imbue (const locale &__loc)

virtual int_type	overflow (int_type __c=traits_type::eof())

virtual int_type	pbackfail (int_type __c=traits_type::eof())

void	pbump (int __n)

virtual pos_type	seekoff (off_type, ios_base::seekdir, ios_base::openmode=ios_base::in\|ios_base::out)

virtual std::streampos	seekoff (std::streamoff __off, std::ios_base::seekdir __dir, std::ios_base::openmode=std::ios_base::in\|std::ios_base::out)

virtual pos_type	seekpos (pos_type, ios_base::openmode=ios_base::in\|ios_base::out)

virtual std::streampos	seekpos (std::streampos __pos, std::ios_base::openmode __mode=std::ios_base::in\|std::ios_base::out)

virtual basic_streambuf< char_type, _Traits > *	setbuf (char_type *, streamsize)

void	setg (char_type __gbeg, char_type __gnext, char_type *__gend)

void	setp (char_type __pbeg, char_type __pend)

virtual streamsize	showmanyc ()

void	swap (basic_streambuf &__sb)

virtual int	sync ()

int_type	syncgetc ()

stdio_sync_filebuf< char >::int_type	syncgetc ()

stdio_sync_filebuf< wchar_t >::int_type	syncgetc ()

int_type	syncputc (int_type __c)

stdio_sync_filebuf< char >::int_type	syncputc (int_type __c)

stdio_sync_filebuf< wchar_t >::int_type	syncputc (int_type __c)

int_type	syncungetc (int_type __c)

stdio_sync_filebuf< char >::int_type	syncungetc (int_type __c)

stdio_sync_filebuf< wchar_t >::int_type	syncungetc (int_type __c)

virtual int_type	uflow ()

virtual int_type	underflow ()

std::streamsize	xsgetn (char *__s, std::streamsize __n)

virtual std::streamsize	xsgetn (char_type *__s, std::streamsize __n)

virtual streamsize	xsgetn (char_type *__s, streamsize __n)

std::streamsize	xsgetn (wchar_t *__s, std::streamsize __n)

std::streamsize	xsputn (const char *__s, std::streamsize __n)

virtual std::streamsize	xsputn (const char_type *__s, std::streamsize __n)

virtual streamsize	xsputn (const char_type *__s, streamsize __n)

std::streamsize	xsputn (const wchar_t *__s, std::streamsize __n)

char_type *	eback () const

char_type *	gptr () const

char_type *	egptr () const

char_type *	pbase () const

char_type *	pptr () const

char_type *	epptr () const

Protected Attributes
locale	_M_buf_locale

char_type *	_M_in_beg

char_type *	_M_in_cur

char_type *	_M_in_end

char_type *	_M_out_beg

char_type *	_M_out_cur

char_type *	_M_out_end

template<typename _CharT, typename _Traits = std::char_traits<_CharT>>
class __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >

Provides a layer of compatibility for C.

This GNU extension provides extensions for working with standard C FILE*'s. It must be instantiated by the user with the type of character used in the file stream, e.g., stdio_filebuf.

Definition at line 58 of file stdio_sync_filebuf.h.

◆ char_type

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

◆ int_type

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

◆ off_type

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

◆ pos_type

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

◆ traits_type

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

◆ stdio_sync_filebuf() [2/2]

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

◆ __safe_gbump()

template<typename _CharT , typename _Traits >

◆ __safe_pbump()

template<typename _CharT , typename _Traits >

◆ eback()

template<typename _CharT , typename _Traits >

◆ egptr()

template<typename _CharT , typename _Traits >

Access to the get area.

These functions are only available to other protected functions, including derived classes.

eback() returns the beginning pointer for the input sequence
gptr() returns the next pointer for the input sequence
egptr() returns the end pointer for the input sequence

Definition at line 495 of file streambuf.

References std::basic_streambuf< _CharT, _Traits >::_M_in_end.

◆ epptr()

template<typename _CharT , typename _Traits >

◆ file()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

Returns

The underlying FILE*.

This function can be used to access the underlying C file pointer. Note that there is no way for the library to track what you do with the file, so be careful.

Definition at line 119 of file stdio_sync_filebuf.h.

◆ gbump()

template<typename _CharT , typename _Traits >

◆ getloc()

template<typename _CharT , typename _Traits >

◆ gptr()

template<typename _CharT , typename _Traits >

Access to the get area.

These functions are only available to other protected functions, including derived classes.

eback() returns the beginning pointer for the input sequence
gptr() returns the next pointer for the input sequence
egptr() returns the end pointer for the input sequence

Definition at line 492 of file streambuf.

References std::basic_streambuf< _CharT, _Traits >::_M_in_cur.

Referenced by std::basic_streambuf< _CharT, _Traits >::in_avail(), std::basic_streambuf< _CharT, _Traits >::sbumpc(), std::basic_streambuf< _CharT, _Traits >::sgetc(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::showmanyc(), std::basic_streambuf< _CharT, _Traits >::sputbackc(), std::basic_streambuf< _CharT, _Traits >::sungetc(), and std::basic_streambuf< _CharT, _Traits >::uflow().

◆ imbue()

template<typename _CharT , typename _Traits >

◆ in_avail()

template<typename _CharT , typename _Traits >

◆ operator=()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

◆ overflow()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

Consumes data from the buffer; writes to the controlled sequence.

Parameters

__c	An additional character to consume.

Returns

eof() to indicate failure, something else (usually __c, or not_eof())

Informally, this function is called when the output buffer is full (or does not exist, as buffering need not actually be done). If a buffer exists, it is consumed, with some effect on the controlled sequence. (Typically, the buffer is written out to the sequence verbatim.) In either case, the character c is also written out, if __c is not eof().

For a formal definition of this function, see a good text such as Langer & Kreft, or [27.5.2.4.5]/3-7.

A functioning output streambuf can be created by overriding only this function (no buffer area will be used).

Note

Base class version does nothing, returns eof().

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

Definition at line 172 of file stdio_sync_filebuf.h.

◆ pbackfail()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

Tries to back up the input sequence.

Parameters

__c	The character to be inserted back into the sequence.

Returns

eof() on failure, some other value on success

Postcondition

The constraints of gptr(), eback(), and pptr() are the same as for underflow().

Note

Base class version does nothing, returns eof().

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

Definition at line 147 of file stdio_sync_filebuf.h.

◆ pbase()

template<typename _CharT , typename _Traits >

◆ pbump()

template<typename _CharT , typename _Traits >

◆ pptr()

template<typename _CharT , typename _Traits >

◆ pubimbue()

template<typename _CharT , typename _Traits >

◆ pubseekoff()

template<typename _CharT , typename _Traits >

◆ pubseekpos()

template<typename _CharT , typename _Traits >

◆ pubsetbuf()

template<typename _CharT , typename _Traits >

◆ pubsync()

template<typename _CharT , typename _Traits >

◆ sbumpc()

template<typename _CharT , typename _Traits >

Getting the next character.

Returns

The next character, or eof.

If the input read position is available, returns that character and increments the read pointer, otherwise calls and returns uflow().

Definition at line 323 of file streambuf.

References std::basic_streambuf< _CharT, _Traits >::egptr(), std::basic_streambuf< _CharT, _Traits >::gbump(), std::basic_streambuf< _CharT, _Traits >::gptr(), and std::basic_streambuf< _CharT, _Traits >::uflow().

Referenced by std::basic_istream< char >::get(), std::basic_istream< _CharT, _Traits >::ignore(), std::istreambuf_iterator< _CharT, _Traits >::operator++(), std::istreambuf_iterator< _CharT, _Traits >::operator++(), std::basic_streambuf< _CharT, _Traits >::snextc(), and std::basic_istream< char >::sync().

◆ seekoff() [1/2]

template<typename _CharT , typename _Traits >

Alters the stream positions.

Each derived class provides its own appropriate behavior.

Note

Base class version does nothing, returns a pos_type that represents an invalid stream position.

Reimplemented in std::basic_filebuf< _CharT, _Traits >, std::basic_filebuf< _CharT, encoding_char_traits< _CharT > >, std::basic_filebuf< _CharT, std::char_traits< _CharT > >, std::basic_filebuf< char_type, traits_type >, and std::basic_stringbuf< _CharT, _Traits, _Alloc >.

Definition at line 609 of file streambuf.

Referenced by std::basic_streambuf< _CharT, _Traits >::pubseekoff().

◆ seekoff() [2/2]

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

◆ seekpos() [1/2]

template<typename _CharT , typename _Traits >

Alters the stream positions.

Each derived class provides its own appropriate behavior.

Note

Base class version does nothing, returns a pos_type that represents an invalid stream position.

Definition at line 621 of file streambuf.

Referenced by std::basic_streambuf< _CharT, _Traits >::pubseekpos().

◆ seekpos() [2/2]

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

◆ setbuf()

template<typename _CharT , typename _Traits >

Manipulates the buffer.

Each derived class provides its own appropriate behavior. See the next-to-last paragraph of https://gcc.gnu.org/onlinedocs/libstdc++/manual/streambufs.html#io.streambuf.buffering for more on this function.

Note

Base class version does nothing, returns this.

Definition at line 598 of file streambuf.

Referenced by std::basic_streambuf< _CharT, _Traits >::pubsetbuf().

◆ setg()

template<typename _CharT , typename _Traits >

◆ setp()

template<typename _CharT , typename _Traits >

◆ sgetc()

template<typename _CharT , typename _Traits >

Getting the next character.

Returns

The next character, or eof.

If the input read position is available, returns that character, otherwise calls and returns underflow(). Does not move the read position after fetching the character.

Definition at line 345 of file streambuf.

References std::basic_streambuf< _CharT, _Traits >::egptr(), std::basic_streambuf< _CharT, _Traits >::gptr(), and std::basic_streambuf< _CharT, _Traits >::underflow().

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry(), std::basic_istream< char >::get(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::ignore(), std::istreambuf_iterator< _CharT, _Traits >::operator++(), std::istreambuf_iterator< _CharT, _Traits >::operator++(), std::basic_istream< char >::readsome(), and std::basic_streambuf< _CharT, _Traits >::snextc().

◆ sgetn()

template<typename _CharT , typename _Traits >

◆ showmanyc()

template<typename _CharT , typename _Traits >

virtual streamsize std::basic_streambuf< _CharT, _Traits >::showmanyc ( )	inlineprotectedvirtualinherited

Investigating the data available.

Returns

An estimate of the number of characters available in the input sequence, or -1.

If it returns a positive value, then successive calls to underflow() will not return traits::eof() until at least that number of characters have been supplied. If showmanyc() returns -1, then calls to underflow() or uflow() will fail. [27.5.2.4.3]/1

Note

Base class version does nothing, returns zero.

The standard adds that the intention is not only that the calls [to underflow or uflow] will not return eof() but that they will return immediately.

The standard adds that the morphemes of showmanyc are es-how-many-see, not show-manic.

Definition at line 656 of file streambuf.

Referenced by std::basic_streambuf< _CharT, _Traits >::in_avail().

◆ snextc()

template<typename _CharT , typename _Traits >

Getting the next character.

Returns

The next character, or eof.

Calls sbumpc(), and if that function returns traits::eof(), so does this function. Otherwise, sgetc().

Definition at line 305 of file streambuf.

References std::basic_streambuf< _CharT, _Traits >::sbumpc(), and std::basic_streambuf< _CharT, _Traits >::sgetc().

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry(), std::basic_istream< char >::get(), std::basic_istream< char >::ignore(), std::basic_istream< char >::operator>>(), and std::basic_istream< char >::putback().

◆ sputbackc()

template<typename _CharT , typename _Traits >

Pushing characters back into the input stream.

Parameters

__c	The character to push back.

Returns

The previous character, if possible.

Similar to sungetc(), but __c is pushed onto the stream instead of the previous character. If successful, the next character fetched from the input stream will be __c.

Definition at line 379 of file streambuf.

References std::basic_streambuf< _CharT, _Traits >::eback(), std::basic_streambuf< _CharT, _Traits >::gbump(), std::basic_streambuf< _CharT, _Traits >::gptr(), and std::basic_streambuf< _CharT, _Traits >::pbackfail().

Referenced by std::basic_istream< _CharT, _Traits >::putback().

◆ sputc()

template<typename _CharT , typename _Traits >

Entry point for all single-character output functions.

Parameters

__c	A character to output.

Returns

__c, if possible.

One of two public output functions.

If a write position is available for the output sequence (i.e., the buffer is not full), stores __c in that position, increments the position, and returns traits::to_int_type(__c). If a write position is not available, returns overflow(__c).

Definition at line 431 of file streambuf.

References std::basic_streambuf< _CharT, _Traits >::epptr(), std::basic_streambuf< _CharT, _Traits >::overflow(), std::basic_streambuf< _CharT, _Traits >::pbump(), and std::basic_streambuf< _CharT, _Traits >::pptr().

Referenced by std::ostreambuf_iterator< _CharT, _Traits >::operator=().

◆ sputn()

template<typename _CharT , typename _Traits >

Entry point for all single-character output functions.

Parameters

__s	A buffer read area.
__n	A count.

One of two public output functions.

Returns xsputn(__s,__n). The effect is to write ___s_[0] through ___s_[__n-1] to the output sequence, if possible.

Definition at line 457 of file streambuf.

References std::basic_streambuf< _CharT, _Traits >::xsputn().

◆ sungetc()

template<typename _CharT , typename _Traits >

Moving backwards in the input stream.

Returns

The previous character, if possible.

If a putback position is available, this function decrements the input pointer and returns that character. Otherwise, calls and returns pbackfail(). The effect is to unget the last character gotten.

Definition at line 404 of file streambuf.

◆ swap() [1/2]

template<typename _CharT , typename _Traits >

◆ swap() [2/2]

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

◆ sync()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

Synchronizes the buffer arrays with the controlled sequences.

Returns

-1 on failure.

Each derived class provides its own appropriate behavior, including the definition of failure.

Note

Base class version does nothing, returns zero.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

Definition at line 191 of file stdio_sync_filebuf.h.

◆ syncgetc() [1/2]

◆ syncgetc() [2/2]

◆ syncputc() [1/2]

◆ syncputc() [2/2]

◆ syncungetc() [1/2]

◆ syncungetc() [2/2]

◆ uflow()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

Fetches more data from the controlled sequence.

Returns

The first character from the pending sequence.

Informally, this function does the same thing as underflow(), and in fact is required to call that function. It also returns the new character, like underflow() does. However, this function also moves the read position forward by one.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

Definition at line 139 of file stdio_sync_filebuf.h.

◆ underflow()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>

Fetches more data from the controlled sequence.

Returns

The first character from the pending sequence.

Informally, this function is called when the input buffer is exhausted (or does not exist, as buffering need not actually be done). If a buffer exists, it is refilled. In either case, the next available character is returned, or traits::eof() to indicate a null pending sequence.

For a formal definition of the pending sequence, see a good text such as Langer & Kreft, or [27.5.2.4.3]/7-14.

A functioning input streambuf can be created by overriding only this function (no buffer area will be used). For an example, see https://gcc.gnu.org/onlinedocs/libstdc++/manual/streambufs.html

Note

Base class version does nothing, returns eof().

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

Definition at line 132 of file stdio_sync_filebuf.h.

◆ xsgetn() [1/3]

◆ xsgetn() [2/3]

template<typename _CharT , typename _Traits >

Multiple character extraction.

Parameters

__s	A buffer area.
__n	Maximum number of characters to assign.

Returns

The number of characters assigned.

Fills ___s_[0] through ___s_[__n-1] with characters from the input sequence, as if by sbumpc(). Stops when either __n characters have been copied, or when traits::eof() would be copied.

It is expected that derived classes provide a more efficient implementation by overriding this definition.

Definition at line 45 of file streambuf.tcc.

References std::min().

Referenced by std::basic_streambuf< _CharT, _Traits >::sgetn().

◆ xsgetn() [3/3]

◆ xsputn() [1/3]

◆ xsputn() [2/3]

template<typename _CharT , typename _Traits >

Multiple character insertion.

Parameters

__s	A buffer area.
__n	Maximum number of characters to write.

Returns

The number of characters written.

Writes ___s_[0] through ___s_[__n-1] to the output sequence, as if by sputc(). Stops when either n characters have been copied, or when sputc() would return traits::eof().

It is expected that derived classes provide a more efficient implementation by overriding this definition.

Definition at line 79 of file streambuf.tcc.

References std::min().

Referenced by std::basic_streambuf< _CharT, _Traits >::sputn().

◆ xsputn() [3/3]

◆ _M_buf_locale

template<typename _CharT , typename _Traits >

◆ _M_in_beg

template<typename _CharT , typename _Traits >

◆ _M_in_cur

template<typename _CharT , typename _Traits >

◆ _M_in_end

template<typename _CharT , typename _Traits >

◆ _M_out_beg

template<typename _CharT , typename _Traits >

◆ _M_out_cur

template<typename _CharT , typename _Traits >

◆ _M_out_end

template<typename _CharT , typename _Traits >

The documentation for this class was generated from the following file:

stdio_sync_filebuf.h