adam/Alepha
1
0
Fork 0
forked from Alepha/Alepha
Code Pull Requests Activity

Make the underlying streambuf private in stacks.

Browse Source
This commit is contained in:
ADAM David Alan Martin
2024-04-03 15:01:52 -04:00
parent 8250680e6c
commit d8689b85e8
5 changed files with 55 additions and 24 deletions
Download Patch File Download Diff File Expand all files Collapse all files

30
IOStreams/StackableStreambuf.cc
View File

@ -4,6 +4,9 @@ static_assert( __cplusplus > 2020'99 );
#include <cassert>
#include <istream>
#include <ostream>
namespace Alepha::Hydrogen::IOStreams::detail::StackableStreambuf_m
{
namespace
@ -47,13 +50,26 @@ namespace Alepha::Hydrogen::IOStreams::detail::StackableStreambuf_m
const auto *const current= dynamic_cast< StackableStreambuf * >( os.rdbuf() );
if( not current ) return false;
os.rdbuf( current->underlying );
current->unhook( os );
releaseTop( os, token );
return true;
}
inline bool
releaseTop( std::istream &is )
{
const auto *const current= dynamic_cast< StackableStreambuf * >( is.rdbuf() );
if( not current ) return false;
current->unhook( is );
releaseTop( is, token );
return true;
}
inline void
releaseStack( std::ios_base &ios )
{
@ -84,6 +100,13 @@ namespace Alepha::Hydrogen::IOStreams::detail::StackableStreambuf_m
return os;
}
std::istream &
impl::operator >> ( std::istream &is, PopStack )
{
if( not releaseTop( is ) ) throw std::logic_error( "IStream has no stacked streambufs!" );
return is;
}
StackableStreambuf::~StackableStreambuf() {}
StackableStreambuf::StackableStreambuf( std::ios &host )
@ -111,4 +134,9 @@ namespace Alepha::Hydrogen::IOStreams::detail::StackableStreambuf_m
for( std::streamsize i= 0; i< amt; ++i ) overflow( data[ i ] );
return amt;
}
void StackableStreambuf::unhook( std::ostream &os ) const { os.rdbuf( underlying ); }
void StackableStreambuf::unhook( std::istream &is ) const { is.rdbuf( underlying ); }
std::ostream &StackableStreambuf::out( std::ostream &&res ) const { res.rdbuf( underlying ); return *&res; }
}

11
IOStreams/StackableStreambuf.h
View File

@ -24,19 +24,24 @@ namespace Alepha::Hydrogen::IOStreams ::detail:: StackableStreambuf_m
struct exports::StackableStreambuf
: virtual public std::streambuf
{
public:
private:
std::streambuf *underlying;
public:
~StackableStreambuf() override;
// Children must be created by `new`.
explicit StackableStreambuf( std::ios &host );
auto out() const { return std::ostream{ underlying }; }
virtual void writeChar( char ch )= 0;
virtual void drain()= 0;
void unhook( std::ostream &os ) const;
void unhook( std::istream &is ) const;
protected:
std::ostream &out( std::ostream &&res= std::ostream{nullptr} ) const;
int overflow( const int ch ) override;
// Underflow is not overridden. A read-oriented