diff options
Diffstat (limited to 'src/mesa/pipe/pipebuffer/pb_buffer_null.c')
-rw-r--r-- | src/mesa/pipe/pipebuffer/pb_buffer_null.c | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/src/mesa/pipe/pipebuffer/pb_buffer_null.c b/src/mesa/pipe/pipebuffer/pb_buffer_null.c new file mode 100644 index 0000000000..a356c6b2d5 --- /dev/null +++ b/src/mesa/pipe/pipebuffer/pb_buffer_null.c @@ -0,0 +1,98 @@ +/************************************************************************** + * + * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas. + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. + * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR + * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, + * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE + * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + **************************************************************************/ + +/** + * \file + * Null buffer implementation. + * + * We have a special null buffer object so that we can safely call buffer + * operations without having to check whether the buffer pointer is null or not. + * + * \author José Fonseca <jrfonseca@tungstengraphics.com> + */ + + +#include "pipe/p_winsys.h" +#include "pipe/p_defines.h" + +#include "pb_buffer.h" + + +static void +null_buffer_reference(struct pipe_buffer *buf) +{ + /* No-op */ +} + + +static void +null_buffer_release(struct pipe_buffer *buf) +{ + /* No-op */ +} + + +static void * +null_buffer_map(struct pipe_buffer *buf, + unsigned flags) +{ + assert(0); + return NULL; +} + + +static void +null_buffer_unmap(struct pipe_buffer *buf) +{ + assert(0); +} + + +static void +null_buffer_get_base_buffer(struct pipe_buffer *buf, + struct pipe_buffer **base_buf, + unsigned *offset) +{ + *base_buf = buf; + *offset = 0; +} + + +const struct pipe_buffer_vtbl +pipe_buffer_vtbl = { + null_buffer_reference, + null_buffer_release, + null_buffer_map, + null_buffer_unmap, + null_buffer_get_base_buffer +}; + + +struct pipe_buffer +null_buffer = { + &pipe_buffer_vtbl +}; |