popen: split up C++ stream part

common/include/villas/popen.hpp

@@ -56,19 +56,14 @@ public:
 	int close();
 	void kill(int signal = SIGINT);
 
-	std::istream &cin()
+	int getFdIn()
 	{
-		return *(input.stream);
+		return fd_in;
 	}
 
-	std::ostream &cout()
+	int getFdOut()
 	{
-		return *(output.stream);
-	}
-
-	int getFd()
-	{
-		return input.buffer->fd();
+		return fd_out;
 	}
 
 	pid_t getPid() const
@@ -84,6 +79,34 @@ protected:
 	bool shell;
 	pid_t pid;
 
+	int fd_in, fd_out;
+};
+
+class PopenStream : public Popen {
+
+public:
+	PopenStream(const std::string &cmd,
+	      const arg_list &args = arg_list(),
+	      const env_map &env = env_map(),
+	      const std::string &wd = std::string(),
+	      bool shell = false);
+	~PopenStream();
+
+	std::istream &cin()
+	{
+		return *(input.stream);
+	}
+
+	std::ostream &cout()
+	{
+		return *(output.stream);
+	}
+
+	void open();
+	int close();
+
+protected:
+
 	struct {
 		std::unique_ptr<std::istream> stream;
 		std::unique_ptr<stdio_buf> buffer;
@@ -99,7 +122,7 @@ protected:
 } /* namespace villas */
 
 template<typename T>
-std::istream &operator>>(villas::utils::Popen &po, T &value)
+std::istream &operator>>(villas::utils::PopenStream &po, T &value)
 {
 	return *(po.input.stream) >> value;
 }

common/lib/popen.cpp

@@ -87,11 +87,8 @@ void Popen::open()
 	if (ret)
 		goto clean_inpipe_out;
 
-	input.buffer = std::make_unique<stdio_buf>(outpipe[READ], std::ios_base::in);
-	output.buffer = std::make_unique<stdio_buf>(inpipe[WRITE], std::ios_base::out);
-
-	input.stream  = std::make_unique<std::istream>(input.buffer.get());
-	output.stream = std::make_unique<std::ostream>(output.buffer.get());
+	fd_in = outpipe[READ];
+	fd_out = inpipe[WRITE];
 
 	pid = fork();
 	if (pid == -1)
@@ -180,13 +177,47 @@ int Popen::close()
 		} while (pid == -1 && errno == EINTR);
 	}
 
+	return pid == -1 ? -1 : pstat;
+}
+
+
+PopenStream::PopenStream(const std::string &cmd,
+             const arg_list &args,
+             const env_map &env,
+             const std::string &wd,
+             bool sh) :
+	Popen(cmd, args, env, wd, sh)
+{
+	open();
+}
+
+PopenStream::~PopenStream()
+{
+	close();
+}
+
+void PopenStream::open()
+{
+	Popen::open();
+
+	input.buffer = std::make_unique<stdio_buf>(fd_in, std::ios_base::in);
+	output.buffer = std::make_unique<stdio_buf>(fd_out, std::ios_base::out);
+
+	input.stream  = std::make_unique<std::istream>(input.buffer.get());
+	output.stream = std::make_unique<std::ostream>(output.buffer.get());
+}
+
+int PopenStream::close()
+{
+	int ret = Popen::close();
+
 	input.stream.reset();
 	output.stream.reset();
 
 	input.buffer.reset();
 	output.buffer.reset();
 
-	return pid == -1 ? -1 : pstat;
+	return ret;
 }
 
 } /* namespace utils */