io: add QIOChannelBuffer class

Add a QIOChannel subclass that is capable of performing I/O
to/from a memory buffer. This implementation does not attempt
to support concurrent readers & writers. It is designed for
serialized access where by a single thread at a time may write
data, seek and then read data back out.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

tests/test-io-channel-buffer.c

@@ -0,0 +1,50 @@
+/*
+ * QEMU I/O channel buffer test
+ *
+ * Copyright (c) 2015 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "io/channel-buffer.h"
+#include "io-channel-helpers.h"
+
+
+static void test_io_channel_buf(void)
+{
+    QIOChannelBuffer *buf;
+    QIOChannelTest *test;
+
+    buf = qio_channel_buffer_new(0);
+
+    test = qio_channel_test_new();
+    qio_channel_test_run_writer(test, QIO_CHANNEL(buf));
+    buf->offset = 0;
+    qio_channel_test_run_reader(test, QIO_CHANNEL(buf));
+    qio_channel_test_validate(test);
+
+    object_unref(OBJECT(buf));
+}
+
+
+int main(int argc, char **argv)
+{
+    module_call_init(MODULE_INIT_QOM);
+
+    g_test_init(&argc, &argv, NULL);
+
+    g_test_add_func("/io/channel/buf", test_io_channel_buf);
+    return g_test_run();
+}