1 files changed, 60 insertions, 0 deletions
diff --git a/src/lib/base/NonBlockingStream.cpp b/src/lib/base/NonBlockingStream.cpp
new file mode 100644
index 0000000..d44add1
--- /dev/null
+++ b/src/lib/base/NonBlockingStream.cpp
@@ -0,0 +1,60 @@
+/*
+ * barrier -- mouse and keyboard sharing utility
+ * Copyright (C) 2008 Debauchee Open Source Group
+ *
+ * This package is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * found in the file LICENSE that should have accompanied this file.
+ *
+ * This package is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#if !defined(_WIN32)
+
+#include "base/NonBlockingStream.h"
+
+#include <unistd.h> // tcgetattr/tcsetattr, read
+#include <termios.h> // tcgetattr/tcsetattr
+#include <fcntl.h>
+#include <errno.h>
+#include <assert.h>
+
+NonBlockingStream::NonBlockingStream(int fd) :
+    _fd(fd)
+{
+    // disable ICANON & ECHO so we don't have to wait for a newline
+    // before we get data (and to keep it from being echoed back out)
+    termios ta;
+    tcgetattr(fd, &ta);
+    _p_ta_previous = new termios(ta);
+    ta.c_lflag &= ~(ICANON | ECHO);
+    tcsetattr(fd, TCSANOW, &ta);
+
+    // prevent IO from blocking so we can poll (read())
+    int _cntl_previous = fcntl(fd, F_GETFL);
+    fcntl(fd, F_SETFL, _cntl_previous | O_NONBLOCK);
+}
+
+NonBlockingStream::~NonBlockingStream()
+{
+    tcsetattr(_fd, TCSANOW, _p_ta_previous);
+    fcntl(_fd, F_SETFL, _cntl_previous);
+    delete _p_ta_previous;
+}
+
+bool NonBlockingStream::try_read_char(char &ch) const
+{
+    int result = read(_fd, &ch, 1);
+    if (result == 1)
+        return true;
+    assert(result == -1 && (errno == EAGAIN || errno == EWOULDBLOCK));
+    return false;
+}
+
+#endif // !defined(_WIN32)