stream-device: Force proper packing of protocol structures

Assuming the packing of structure can be a portability issue.
Currently there are no real-world ABI that would break these structure
however to be safe force a 4 byte packing.

Signed-off-by: Frediano Ziglio <fziglio@redhat.com>

4 files changed, 99 insertions, 0 deletions

diff --git a/spice/end-packed4.h b/spice/end-packed4.h
new file mode 100644
index 0000000..79fd74c
--- /dev/null
+++ b/spice/end-packed4.h
@@ -0,0 +1,34 @@
+/* -*- Mode: C; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
+/*
+   Copyright (C) 2009-2018 Red Hat, Inc.
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are
+   met:
+
+       * Redistributions of source code must retain the above copyright
+         notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above copyright
+         notice, this list of conditions and the following disclaimer in
+         the documentation and/or other materials provided with the
+         distribution.
+       * Neither the name of the copyright holder nor the names of its
+         contributors may be used to endorse or promote products derived
+         from this software without specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS "AS
+   IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+   TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+   PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+/* See start-packed4.h for details */
+
+#pragma pack(pop)
diff --git a/spice/meson.build b/spice/meson.build
index 37268df..c871b86 100644
--- a/spice/meson.build
+++ b/spice/meson.build
@@ -1,6 +1,7 @@
 spice_protocol_headers = [
   'barrier.h',
   'end-packed.h',
+  'end-packed4.h',
   'enums.h',
   'ipc_ring.h',
   'macros.h',
@@ -8,6 +9,7 @@ spice_protocol_headers = [
   'qxl_dev.h',
   'qxl_windows.h',
   'start-packed.h',
+  'start-packed4.h',
   'stats.h',
   'types.h',
   'vd_agent.h',
diff --git a/spice/start-packed4.h b/spice/start-packed4.h
new file mode 100644
index 0000000..996f640
--- /dev/null
+++ b/spice/start-packed4.h
@@ -0,0 +1,59 @@
+/* -*- Mode: C; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
+/*
+   Copyright (C) 2009-2018 Red Hat, Inc.
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are
+   met:
+
+       * Redistributions of source code must retain the above copyright
+         notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above copyright
+         notice, this list of conditions and the following disclaimer in
+         the documentation and/or other materials provided with the
+         distribution.
+       * Neither the name of the copyright holder nor the names of its
+         contributors may be used to endorse or promote products derived
+         from this software without specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS "AS
+   IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+   TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+   PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+/* Ideally this should all have been macros in a common headers, but
+ * its not possible to put pragmas into header files, so we have
+ * to use include magic.
+ *
+ * Use it like this:
+ *
+ * #include <spice/start-packed4.h>
+ *
+ * typedef struct {
+ *    ...
+ * } Type;
+ *
+ * #include <spice/end-packed4.h>
+ *
+ */
+
+#ifdef __GNUC__
+
+#pragma pack(push,4)
+
+#else
+
+#pragma pack(push)
+#pragma pack(4)
+#pragma warning(disable:4200)
+#pragma warning(disable:4103)
+
+#endif
diff --git a/spice/stream-device.h b/spice/stream-device.h
index 15d839b..e559f16 100644
--- a/spice/stream-device.h
+++ b/spice/stream-device.h
@@ -42,6 +42,8 @@
 
 #include <spice/types.h>
 
+#include <spice/start-packed4.h>
+
 /*
  * Structures are all "naturally aligned"
  * containing integers up to 64 bit.
@@ -267,4 +269,6 @@ typedef struct StreamMsgCursorMove {
     int32_t y;
 } StreamMsgCursorMove;
 
+#include <spice/end-packed4.h>
+
 #endif /* SPICE_STREAM_DEVICE_H_ */