libstdc++
__gnu_cxx::stdio_sync_filebuf< _CharT, _Traits > Class Template Reference
Inheritance diagram for __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >:
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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_filebufoperator= (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_streambufpubsetbuf (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 overflow (int_type __c=traits_type::eof())
 
virtual int_type pbackfail (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 std::streampos seekpos (std::streampos __pos, std::ios_base::openmode __mode=std::ios_base::in|std::ios_base::out)
 
virtual basic_streambuf< char_type, std::char_traits< _CharT > > * 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
 

Detailed Description

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<char>.

Definition at line 56 of file stdio_sync_filebuf.h.

Member Function Documentation

◆ eback()

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::eback ( ) const
inlineprotectedinherited

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 487 of file streambuf.

◆ egptr()

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::egptr ( ) const
inlineprotectedinherited

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 493 of file streambuf.

◆ epptr()

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::epptr ( ) const
inlineprotectedinherited

Access to the put area.

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

  • pbase() returns the beginning pointer for the output sequence
  • pptr() returns the next pointer for the output sequence
  • epptr() returns the end pointer for the output sequence

Definition at line 540 of file streambuf.

◆ file()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
std::__c_file* __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >::file ( )
inline
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 117 of file stdio_sync_filebuf.h.

◆ gbump()

void std::basic_streambuf< _CharT, std::char_traits< _CharT > >::gbump ( int  __n)
inlineprotectedinherited

Moving the read position.

Parameters
__nThe delta by which to move.

This just advances the read position without returning any data.

Definition at line 503 of file streambuf.

◆ getloc()

locale std::basic_streambuf< _CharT, std::char_traits< _CharT > >::getloc ( ) const
inlineinherited

Locale access.

Returns
The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 231 of file streambuf.

◆ gptr()

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::gptr ( ) const
inlineprotectedinherited

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 490 of file streambuf.

◆ imbue()

virtual void std::basic_streambuf< _CharT, std::char_traits< _CharT > >::imbue ( const locale __loc)
inlineprotectedvirtualinherited

Changes translations.

Parameters
__locA new locale.

Translations done during I/O which depend on the current locale are changed by this call. The standard adds, Between invocations of this function a class derived from streambuf can safely cache results of calls to locale functions and to members of facets so obtained.

Note
Base class version does nothing.

Reimplemented in std::basic_filebuf< _CharT, std::char_traits< _CharT > >.

Definition at line 581 of file streambuf.

◆ in_avail()

streamsize std::basic_streambuf< _CharT, std::char_traits< _CharT > >::in_avail ( )
inlineinherited

Looking ahead into the stream.

Returns
The number of characters available.

If a read position is available, returns the number of characters available for reading before the buffer must be refilled. Otherwise returns the derived showmanyc().

Definition at line 289 of file streambuf.

◆ overflow()

virtual int_type std::basic_streambuf< _CharT, std::char_traits< _CharT > >::overflow ( int_type  __c = traits_type::eof())
inlineprotectedvirtualinherited

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

Parameters
__cAn 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().

Definition at line 773 of file streambuf.

◆ pbackfail()

virtual int_type std::basic_streambuf< _CharT, std::char_traits< _CharT > >::pbackfail ( int_type  __c = traits_type::eof())
inlineprotectedvirtualinherited

Tries to back up the input sequence.

Parameters
__cThe 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().

Definition at line 729 of file streambuf.

◆ pbase()

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::pbase ( ) const
inlineprotectedinherited

Access to the put area.

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

  • pbase() returns the beginning pointer for the output sequence
  • pptr() returns the next pointer for the output sequence
  • epptr() returns the end pointer for the output sequence

Definition at line 534 of file streambuf.

◆ pbump()

void std::basic_streambuf< _CharT, std::char_traits< _CharT > >::pbump ( int  __n)
inlineprotectedinherited

Moving the write position.

Parameters
__nThe delta by which to move.

This just advances the write position without returning any data.

Definition at line 550 of file streambuf.

◆ pptr()

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::pptr ( ) const
inlineprotectedinherited

Access to the put area.

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

  • pbase() returns the beginning pointer for the output sequence
  • pptr() returns the next pointer for the output sequence
  • epptr() returns the end pointer for the output sequence

Definition at line 537 of file streambuf.

◆ pubimbue()

locale std::basic_streambuf< _CharT, std::char_traits< _CharT > >::pubimbue ( const locale __loc)
inlineinherited

Entry point for imbue().

Parameters
__locThe new locale.
Returns
The previous locale.

Calls the derived imbue(__loc).

Definition at line 214 of file streambuf.

◆ pubseekoff()

pos_type std::basic_streambuf< _CharT, std::char_traits< _CharT > >::pubseekoff ( off_type  __off,
ios_base::seekdir  __way,
ios_base::openmode  __mode = ios_base::in | ios_base::out 
)
inlineinherited

Alters the stream position.

Parameters
__offOffset.
__wayValue for ios_base::seekdir.
__modeValue for ios_base::openmode.

Calls virtual seekoff function.

Definition at line 256 of file streambuf.

◆ pubseekpos()

pos_type std::basic_streambuf< _CharT, std::char_traits< _CharT > >::pubseekpos ( pos_type  __sp,
ios_base::openmode  __mode = ios_base::in | ios_base::out 
)
inlineinherited

Alters the stream position.

Parameters
__spPosition
__modeValue for ios_base::openmode.

Calls virtual seekpos function.

Definition at line 268 of file streambuf.

◆ pubsetbuf()

basic_streambuf* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::pubsetbuf ( char_type __s,
streamsize  __n 
)
inlineinherited

Entry points for derived buffer functions.

The public versions of pubfoo dispatch to the protected derived foo member functions, passing the arguments (if any) and returning the result unchanged.

Definition at line 244 of file streambuf.

◆ pubsync()

int std::basic_streambuf< _CharT, std::char_traits< _CharT > >::pubsync ( )
inlineinherited

Calls virtual sync function.

Definition at line 276 of file streambuf.

◆ sbumpc()

int_type std::basic_streambuf< _CharT, std::char_traits< _CharT > >::sbumpc ( )
inlineinherited

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 321 of file streambuf.

◆ seekoff()

virtual pos_type std::basic_streambuf< _CharT, std::char_traits< _CharT > >::seekoff ( off_type  ,
ios_base::seekdir  ,
ios_base::openmode  = ios_base::in | ios_base::out 
)
inlineprotectedvirtualinherited

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 607 of file streambuf.

◆ seekpos()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
virtual std::streampos __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >::seekpos ( std::streampos  ,
std::ios_base::openmode  = std::ios_base::in | std::ios_base::out 
)
inlineprotectedvirtual

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 from std::basic_streambuf< _CharT, std::char_traits< _CharT > >.

Definition at line 215 of file stdio_sync_filebuf.h.

References std::ios_base::beg.

◆ setbuf()

virtual basic_streambuf<char_type,std::char_traits< _CharT > >* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::setbuf ( char_type ,
streamsize   
)
inlineprotectedvirtualinherited

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.

Reimplemented in std::basic_filebuf< _CharT, std::char_traits< _CharT > >.

Definition at line 596 of file streambuf.

◆ setg()

void std::basic_streambuf< _CharT, std::char_traits< _CharT > >::setg ( char_type __gbeg,
char_type __gnext,
char_type __gend 
)
inlineprotectedinherited

Setting the three read area pointers.

Parameters
__gbegA pointer.
__gnextA pointer.
__gendA pointer.
Postcondition
__gbeg == eback(), __gnext == gptr(), and __gend == egptr()

Definition at line 514 of file streambuf.

◆ setp()

void std::basic_streambuf< _CharT, std::char_traits< _CharT > >::setp ( char_type __pbeg,
char_type __pend 
)
inlineprotectedinherited

Setting the three write area pointers.

Parameters
__pbegA pointer.
__pendA pointer.
Postcondition
__pbeg == pbase(), __pbeg == pptr(), and __pend == epptr()

Definition at line 560 of file streambuf.

◆ sgetc()

int_type std::basic_streambuf< _CharT, std::char_traits< _CharT > >::sgetc ( )
inlineinherited

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 343 of file streambuf.

◆ sgetn()

streamsize std::basic_streambuf< _CharT, std::char_traits< _CharT > >::sgetn ( char_type __s,
streamsize  __n 
)
inlineinherited

Entry point for xsgetn.

Parameters
__sA buffer area.
__nA count.

Returns xsgetn(__s,__n). The effect is to fill __s[0] through __s[__n-1] with characters from the input sequence, if possible.

Definition at line 362 of file streambuf.

◆ showmanyc()

virtual streamsize std::basic_streambuf< _CharT, std::char_traits< _CharT > >::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.

Reimplemented in std::basic_filebuf< _CharT, std::char_traits< _CharT > >.

Definition at line 654 of file streambuf.

◆ snextc()

int_type std::basic_streambuf< _CharT, std::char_traits< _CharT > >::snextc ( )
inlineinherited

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 303 of file streambuf.

◆ sputbackc()

int_type std::basic_streambuf< _CharT, std::char_traits< _CharT > >::sputbackc ( char_type  __c)
inlineinherited

Pushing characters back into the input stream.

Parameters
__cThe 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 377 of file streambuf.

◆ sputc()

int_type std::basic_streambuf< _CharT, std::char_traits< _CharT > >::sputc ( char_type  __c)
inlineinherited

Entry point for all single-character output functions.

Parameters
__cA 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 429 of file streambuf.

◆ sputn()

streamsize std::basic_streambuf< _CharT, std::char_traits< _CharT > >::sputn ( const char_type __s,
streamsize  __n 
)
inlineinherited

Entry point for all single-character output functions.

Parameters
__sA buffer read area.
__nA 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 455 of file streambuf.

◆ sungetc()

int_type std::basic_streambuf< _CharT, std::char_traits< _CharT > >::sungetc ( )
inlineinherited

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 402 of file streambuf.

◆ sync()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
virtual int __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >::sync ( void  )
inlineprotectedvirtual

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, std::char_traits< _CharT > >.

Definition at line 189 of file stdio_sync_filebuf.h.

◆ uflow()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
virtual int_type __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >::uflow ( )
inlineprotectedvirtual

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, std::char_traits< _CharT > >.

Definition at line 137 of file stdio_sync_filebuf.h.

◆ underflow()

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
virtual int_type __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >::underflow ( )
inlineprotectedvirtual

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, std::char_traits< _CharT > >.

Definition at line 130 of file stdio_sync_filebuf.h.

◆ xsgetn()

streamsize std::basic_streambuf< _CharT, std::char_traits< _CharT > >::xsgetn ( char_type __s,
streamsize  __n 
)
protectedvirtualinherited

Multiple character extraction.

Parameters
__sA buffer area.
__nMaximum 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.

Reimplemented in std::basic_filebuf< _CharT, std::char_traits< _CharT > >.

Definition at line 670 of file streambuf.tcc.

◆ xsputn()

streamsize std::basic_streambuf< _CharT, std::char_traits< _CharT > >::xsputn ( const char_type __s,
streamsize  __n 
)
protectedvirtualinherited

Multiple character insertion.

Parameters
__sA buffer area.
__nMaximum 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.

Reimplemented in std::basic_filebuf< _CharT, std::char_traits< _CharT > >.

Definition at line 747 of file streambuf.tcc.

Member Data Documentation

◆ _M_buf_locale

locale std::basic_streambuf< _CharT, std::char_traits< _CharT > >::_M_buf_locale
protectedinherited

Current locale setting.

Definition at line 197 of file streambuf.

◆ _M_in_beg

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::_M_in_beg
protectedinherited

Start of get area.

Definition at line 189 of file streambuf.

◆ _M_in_cur

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::_M_in_cur
protectedinherited

Current read area.

Definition at line 190 of file streambuf.

◆ _M_in_end

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::_M_in_end
protectedinherited

End of get area.

Definition at line 191 of file streambuf.

◆ _M_out_beg

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::_M_out_beg
protectedinherited

Start of put area.

Definition at line 192 of file streambuf.

◆ _M_out_cur

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::_M_out_cur
protectedinherited

Current put area.

Definition at line 193 of file streambuf.

◆ _M_out_end

char_type* std::basic_streambuf< _CharT, std::char_traits< _CharT > >::_M_out_end
protectedinherited

End of put area.

Definition at line 194 of file streambuf.


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