implemented fdstream, introduced iostream extension with new fdstreams

alib2std/src/extensions/fdstream.cpp

+/*
+ * Author: Radovan Cerveny
+ */
+
+#include "fdstream.hpp"
+
+namespace std {
+
+fdstreambuf::fdstreambuf ( int fd ) : fd ( fd ) {
+	setp ( buff.begin ( ), buff.end ( ) - 1 );
+}
+
+bool fdstreambuf::flush ( ) {
+	std::ptrdiff_t n = pptr ( ) - pbase ( );
+
+	ssize_t osz = write ( fd, buff.data ( ), n );
+
+	pbump ( -n );
+
+	return osz != -1;
+}
+
+fdstreambuf::int_type fdstreambuf::overflow ( fdstreambuf::int_type ch ) {
+	if ( ch == traits_type::eof ( ) ) return traits_type::eof ( );
+
+	buff.back ( ) = ch;
+
+	pbump ( 1 );
+
+	if ( !flush ( ) ) return traits_type::eof ( );
+
+	return ch;
+}
+
+int fdstreambuf::sync ( ) {
+	return flush ( ) ? 0 : -1;
+}
+
+fdaccessor::fdaccessor ( int new_fd ) {
+	int res = fcntl ( new_fd, F_GETFD );
+
+	fd = res == 0 ? new_fd : -1;
+}
+
+int fdaccessor::get_fd ( ) {
+	return fd;
+}
+
+ofdstream::ofdstream ( int fd ) : fda ( fd ), fdbuf ( fda.get_fd ( ) ) {
+	this->init ( & fdbuf );
+
+	if ( fda.get_fd ( ) == -1 )
+		setstate ( ios_base::failbit );
+}
+
+}

alib2std/src/extensions/fdstream.hpp

+/*
+ * Author: Radovan Cerveny
+ */
+
+/*
+ * ofdstream
+ * ofdstream takes a file descriptor (fd) by constructor to use for output
+ * if the file descriptor is not valid for any reason during construction of the ofdstream, ofdstream will set its state to ios::fail
+ * if the file descriptor is valid, it is used for successive buffered output
+ *
+ * supplied file descriptor has to be already open in order for ofdstream to work
+ * ofdstream does not close the file descriptor and does not change internal flags of the file descriptor during the lifetime of ofdstream and during destruction of ofdstream
+ */
+
+#ifndef FDSTREAM_HPP_
+#define FDSTREAM_HPP_
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <ostream>
+#include <array>
+
+namespace std {
+
+class fdstreambuf : public streambuf {
+	static const size_t buff_sz = 512;
+
+	int fd;
+	array < char_type, buff_sz > buff;
+
+	bool flush ( );
+
+protected:
+	int_type overflow ( int_type );
+	int sync ( );
+
+public:
+	explicit fdstreambuf ( int );
+	fdstreambuf ( const fdstreambuf & ) = delete;
+	fdstreambuf & operator =( const fdstreambuf & ) = delete;
+};
+
+class fdaccessor {
+	int fd;
+
+public:
+	explicit fdaccessor ( int );
+	int get_fd ( );
+};
+
+class ofdstream : public ostream {
+	fdaccessor fda;
+	fdstreambuf fdbuf;
+
+public:
+	explicit ofdstream ( int );
+	virtual ~ofdstream ( ) { }
+};
+
+}
+
+#endif /* FDSTREAM_HPP_ */

alib2std/src/extensions/iostream.cpp

+/*
+ * Author: Radovan Cerveny
+ */
+
+#include "iostream.hpp"
+
+namespace std {
+
+ // used for measurements output
+const int CMEASURE_FD = 5;
+ofdstream cmeasure ( CMEASURE_FD );
+}

alib2std/src/extensions/iostream.hpp

+/*
+ * Author: Radovan Cerveny
+ */
+
+#ifndef IOSTREAM_HPP_
+#define IOSTREAM_HPP_
+
+#include "fdstream.hpp"
+
+namespace std {
+
+ // used for measurements output
+extern const int CMEASURE_FD;
+extern ofdstream cmeasure;
+}
+
+#endif /* IOSTREAM_HPP_ */

alib2std/src/fdstream

+#ifndef __FDSTREAM_HEADER_WRAPPER_
+#define __FDSTREAM_HEADER_WRAPPER_
+
+#include "extensions/fdstream.hpp"
+
+#endif /* __FDSTREAM_HEADER_WRAPPER_ */

alib2std/src/iostream

+#ifndef __IOSTREAM_HEADER_WRAPPER_
+#define __IOSTREAM_HEADER_WRAPPER_
+
+#include <bits/../iostream>
+#include "extensions/iostream.hpp"
+
+#endif /* __IOSTREAM_HEADER_WRAPPER_ */