[aravis] gc_port: avoid warning when trying to access invalid chunk data

[Emmanuel Pacaud <emmanuel src gnome org>]

commit 2d1f015b086bd6fa360047603c65dfccadb2f1ef
Author: Emmanuel Pacaud <emmanuel gnome org>
Date:   Wed Aug 20 22:57:13 2014 +0200

    gc_port: avoid warning when trying to access invalid chunk data
    
    The warning happened when the chunk data name was one of the device
    feature name.

 src/arvgcport.c |   59 ++++++++++++++++++++++++++++++++----------------------
 1 files changed, 35 insertions(+), 24 deletions(-)
---
diff --git a/src/arvgcport.c b/src/arvgcport.c
index 9010874..bebac26 100644
--- a/src/arvgcport.c
+++ b/src/arvgcport.c
@@ -103,20 +103,25 @@ arv_gc_port_read (ArvGcPort *port, void *buffer, guint64 address, guint64 length
                ArvDevice *device;
 
                device = arv_gc_get_device (genicam);
-
-               /* For schema < 1.1.0 and length == 4, register read must be used instead of memory read.
-                * See Appendix 3 of Genicam 2.0 specification. */
-               if (_register_workaround_check (port, length)) {
-                       guint32 value;
-
-                       /* For schema < 1.1.0, all registers are big endian. */
-                       value = *((guint32 *) buffer);
-                       value = GUINT32_FROM_BE (value);
-
-                       arv_device_read_register (device, address, &value, error);
-                       *((guint32 *) buffer) = GUINT32_TO_BE (value);
-               } else
-                       arv_device_read_memory (device, address, length, buffer, error);
+               if (ARV_IS_DEVICE (device)) {
+                       /* For schema < 1.1.0 and length == 4, register read must be used instead of memory 
read.
+                        * See Appendix 3 of Genicam 2.0 specification. */
+                       if (_register_workaround_check (port, length)) {
+                               guint32 value;
+
+                               /* For schema < 1.1.0, all registers are big endian. */
+                               value = *((guint32 *) buffer);
+                               value = GUINT32_FROM_BE (value);
+
+                               arv_device_read_register (device, address, &value, error);
+                               *((guint32 *) buffer) = GUINT32_TO_BE (value);
+                       } else
+                               arv_device_read_memory (device, address, length, buffer, error);
+               } else {
+                       if (error != NULL && *error == NULL)
+                               *error = g_error_new (ARV_CHUNK_PARSER_ERROR, 
ARV_CHUNK_PARSER_STATUS_INVALID_FEATURE_NAME,
+                                                     "[ArvGcPort::read] Invalid feature name");
+               }
        } else {
                ArvBuffer *chunk_data_buffer;
 
@@ -160,18 +165,24 @@ arv_gc_port_write (ArvGcPort *port, void *buffer, guint64 address, guint64 lengt
        if (port->priv->chunk_id == NULL) {
                device = arv_gc_get_device (genicam);
 
-               /* For schema < 1.1.0 and length == 4, register write must be used instead of memory write.
-                * See Appendix 3 of Genicam 2.0 specification. */
-               if (_register_workaround_check (port, length)) {
-                       guint32 value;
+               if (ARV_IS_DEVICE (device)) {
+                       /* For schema < 1.1.0 and length == 4, register write must be used instead of memory 
write.
+                        * See Appendix 3 of Genicam 2.0 specification. */
+                       if (_register_workaround_check (port, length)) {
+                               guint32 value;
 
-                       /* For schema < 1.1.0, all registers are big endian. */
-                       value = *((guint32 *) buffer);
-                       value = GUINT32_FROM_BE (value);
+                               /* For schema < 1.1.0, all registers are big endian. */
+                               value = *((guint32 *) buffer);
+                               value = GUINT32_FROM_BE (value);
 
-                       arv_device_write_register (device, address, value, error);
-               } else
-                       arv_device_write_memory (device, address, length, buffer, error);
+                               arv_device_write_register (device, address, value, error);
+                       } else
+                               arv_device_write_memory (device, address, length, buffer, error);
+               } else {
+                       if (error != NULL && *error == NULL)
+                               *error = g_error_new (ARV_CHUNK_PARSER_ERROR, 
ARV_CHUNK_PARSER_STATUS_INVALID_FEATURE_NAME,
+                                                     "[ArvGcPort::write] Invalid feature name");
+               }
        } else {
                ArvBuffer *chunk_data_buffer;