[aravis] buffer: change buffer.data type to char *, instead of void *.

[Emmanuel Pacaud <emmanuel src gnome org>]

commit 1385d2a4687f5da623181143bd9308d693819d4b
Author: Emmanuel Pacaud <emmanuel gnome org>
Date:   Sun Nov 3 21:32:29 2013 +0100

    buffer: change buffer.data type to char *, instead of void *.
    
    untyped pointers seem to be handled incorrectly by language bindings.
    It should fix https://bugzilla.gnome.org/show_bug.cgi?id=706531.

 src/arvbuffer.h                        |    2 +-
 tests/python/arv-camera-test.py        |    2 +-
 tests/python/arv-single-buffer-test.py |  103 ++++++++++++++++++++++++++++++++
 3 files changed, 105 insertions(+), 2 deletions(-)
---
diff --git a/src/arvbuffer.h b/src/arvbuffer.h
index 983ab15..4003e14 100644
--- a/src/arvbuffer.h
+++ b/src/arvbuffer.h
@@ -66,7 +66,7 @@ struct _ArvBuffer {
 
        size_t size;
        gboolean is_preallocated;
-       void *data;
+       char *data;
 
        void *user_data;
        GDestroyNotify user_data_destroy_func;
diff --git a/tests/python/arv-camera-test.py b/tests/python/arv-camera-test.py
index 76386c1..db4290f 100644
--- a/tests/python/arv-camera-test.py
+++ b/tests/python/arv-camera-test.py
@@ -73,7 +73,7 @@ print "Acquisition"
 
 for i in range(0,20):
        buffer = stream.pop_buffer ()
-       print buffer.data
+       print buffer
        if buffer:
                stream.push_buffer (buffer)
 
diff --git a/tests/python/arv-single-buffer-test.py b/tests/python/arv-single-buffer-test.py
new file mode 100644
index 0000000..615d188
--- /dev/null
+++ b/tests/python/arv-single-buffer-test.py
@@ -0,0 +1,103 @@
+#!/usr/bin/env python
+
+# Aravis - Digital camera library
+#
+# Copyright (c) 2011 Emmanuel Pacaud
+#
+# 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, write to the
+# Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+# Boston, MA 02111-1307, USA.
+#
+# Author: Emmanuel Pacaud <emmanuel gnome org>
+
+#  If you have installed aravis in a non standard location, you may need
+#   to make GI_TYPELIB_PATH point to the correct location. For example:
+#
+#   export GI_TYPELIB_PATH=$GI_TYPELIB_PATH:/opt/bin/lib/girepositry-1.0/
+#
+#  You may also have to give the path to libaravis.so, using LD_PRELOAD or
+#  LD_LIBRARY_PATH.
+
+import sys
+import time
+
+from gi.repository import Aravis
+
+def DumpBuffer (buf, length, caption="", dest=sys.stdout):
+       def GetPrintableChar(str):
+               if str.isalpha():
+                       return str
+               else:
+                       return '.'
+
+       dest.write('---------> %s <--------- (%d bytes)\n' % (caption, length))
+       dest.write('       +0          +4          +8          +c           0   4   8   c\n')
+       i = 0
+       while i < length:
+               if length - i > 16:
+                       l = 16
+               else:
+                       l = length - i
+
+               dest.write('+%04x  ' % i)
+               s = ' '.join(["%02x" % ord(c) for c in buf[i:i + l]])
+               dest.write(s)
+               sp = 49 - len(s)
+               dest.write(' ' * sp)
+               s = ''.join(["%c" % GetPrintableChar(c) for c in buf[i:i + l]])
+               dest.write(s)
+               dest.write('\n')
+
+               i = i + 16
+
+Aravis.enable_interface ("Fake")
+
+try:
+       if len(sys.argv) > 1:
+               camera = Aravis.Camera.new (sys.argv[1])
+       else:
+               camera = Aravis.Camera.new (None)
+except:
+       print ("No camera found")
+       exit ()
+
+payload = camera.get_payload ()
+
+[x,y,width,height] = camera.get_region ()
+
+print "Camera vendor : %s" %(camera.get_vendor_name ())
+print "Camera model  : %s" %(camera.get_model_name ())
+print "Camera id     : %s" %(camera.get_device_id ())
+print "ROI           : %dx%d at %d,%d" %(width, height, x, y)
+print "Payload       : %d" %(payload)
+print "Pixel format  : %s" %(camera.get_pixel_format_as_string ())
+
+stream = camera.create_stream (None, None)
+
+stream.push_buffer (Aravis.Buffer.new_allocate (payload))
+
+print "Start acquisition"
+
+camera.start_acquisition ()
+
+print "Acquisition"
+
+buffer = stream.pop_buffer ()
+
+DumpBuffer (buffer.data, buffer.size, "Image buffer")
+
+print "Stop acquisition"
+
+camera.stop_acquisition ()
+