From: Mikko Rasa <tdb@tdb.fi>
Date: Wed, 30 May 2012 19:00:56 +0000 (+0000)
Subject: Add functions to support console redirection
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=5b541316a8c7bbf8b812c0f1e2dbebaa6563b0ee;p=libs%2Fcore.git

Add functions to support console redirection
---

diff --git a/source/io/base.cpp b/source/io/base.cpp
index bf4c820..052d464 100644
--- a/source/io/base.cpp
+++ b/source/io/base.cpp
@@ -57,5 +57,10 @@ void Base::set_eof()
 	}
 }
 
+const Handle &Base::get_handle(Mode)
+{
+	throw logic_error("Base::get_handle");
+}
+
 } // namespace IO
 } // namespace Msp
diff --git a/source/io/base.h b/source/io/base.h
index 61819cf..3d86216 100644
--- a/source/io/base.h
+++ b/source/io/base.h
@@ -2,6 +2,7 @@
 #define MSP_IO_BASE_H_
 
 #include <sigc++/sigc++.h>
+#include "handle.h"
 #include "mode.h"
 #include "poll.h"
 
@@ -88,6 +89,10 @@ protected:
 public:
 	/** Returns the end-of-file flag. */
 	bool eof() const { return eof_flag; }
+
+	/** Returns the system-level handle for the object.  Used by Console to
+	perform redirections. */
+	virtual const Handle &get_handle(Mode);
 };
 
 } // namespace IO
diff --git a/source/io/console.cpp b/source/io/console.cpp
index d06b894..259f80f 100644
--- a/source/io/console.cpp
+++ b/source/io/console.cpp
@@ -1,5 +1,6 @@
 #ifndef WIN32
 #include <errno.h>
+#include <unistd.h>
 #include <fcntl.h>
 #include <termios.h>
 #include <sys/ioctl.h>
@@ -125,6 +126,16 @@ void Console::get_size(unsigned &rows, unsigned &cols)
 #endif
 }
 
+void Console::redirect(Base &other)
+{
+	Handle other_handle = other.get_handle(mode&M_RDWR);
+#ifdef WIN32
+	SetStdHandle(stream_to_sys(stream), *other_handle);
+#else
+	dup2(*other_handle, *handle);
+#endif
+}
+
 unsigned Console::do_write(const char *buf, unsigned len)
 {
 	check_access(M_WRITE);
diff --git a/source/io/console.h b/source/io/console.h
index 5b4158f..d29ef00 100644
--- a/source/io/console.h
+++ b/source/io/console.h
@@ -46,6 +46,11 @@ public:
 	Console. */
 	void get_size(unsigned &rows, unsigned &cols);
 
+	/** Redirects input from or output to another I/O object.  This performs a
+	system-level redirect.  Closing the other object won't affect the
+	redirection. */
+	void redirect(Base &);
+
 protected:
 	virtual unsigned do_write(const char *, unsigned);
 	virtual unsigned do_read(char *, unsigned);