+++ /dev/null
-/**************************************************************************
- *
- * Copyright 2009 Younes Manton.
- * 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.
- *
- **************************************************************************/
-
-#include "vl_bitstream_parser.h"
-#include <assert.h>
-#include <limits.h>
-#include <util/u_memory.h>
-#include <stdio.h>
-
-inline void endian_swap_ushort(unsigned short *x)
-{
- x[0] = (x[0]>>8) |
- (x[0]<<8);
-}
-
-inline void endian_swap_uint(unsigned int *x)
-{
- x[0] = (x[0]>>24) |
- ((x[0]<<8) & 0x00FF0000) |
- ((x[0]>>8) & 0x0000FF00) |
- (x[0]<<24);
-}
-
-inline void endian_swap_ulonglong(unsigned long long *x)
-{
- x[0] = (x[0]>>56) |
- ((x[0]<<40) & 0x00FF000000000000) |
- ((x[0]<<24) & 0x0000FF0000000000) |
- ((x[0]<<8) & 0x000000FF00000000) |
- ((x[0]>>8) & 0x00000000FF000000) |
- ((x[0]>>24) & 0x0000000000FF0000) |
- ((x[0]>>40) & 0x000000000000FF00) |
- (x[0]<<56);
-}
-
-static unsigned
-grab_bits(unsigned cursor, unsigned how_many_bits, unsigned bitstream_elt)
-{
- unsigned excess_bits = sizeof(unsigned) * CHAR_BIT - how_many_bits;
-
- assert(cursor < sizeof(unsigned) * CHAR_BIT);
- assert(how_many_bits > 0 && how_many_bits <= sizeof(unsigned) * CHAR_BIT);
- assert(cursor + how_many_bits <= sizeof(unsigned) * CHAR_BIT);
-
- #ifndef PIPE_ARCH_BIG_ENDIAN
- switch (sizeof(unsigned)) {
- case 2:
- endian_swap_ushort(&bitstream_elt);
- break;
- case 4:
- endian_swap_uint(&bitstream_elt);
- break;
- case 8:
- endian_swap_ulonglong(&bitstream_elt);
- break;
- }
- #endif // !PIPE_ARCH_BIG_ENDIAN
-
- return (bitstream_elt << cursor) >> (excess_bits);
-}
-
-static unsigned
-show_bits(unsigned cursor, unsigned how_many_bits, const unsigned *bitstream)
-{
- unsigned cur_int = cursor / (sizeof(unsigned) * CHAR_BIT);
- unsigned cur_bit = cursor % (sizeof(unsigned) * CHAR_BIT);
-
- assert(bitstream);
-
- if (cur_bit + how_many_bits > sizeof(unsigned) * CHAR_BIT) {
- unsigned lower = grab_bits(cur_bit, sizeof(unsigned) * CHAR_BIT - cur_bit,
- bitstream[cur_int]);
- unsigned upper = grab_bits(0, cur_bit + how_many_bits - sizeof(unsigned) * CHAR_BIT,
- bitstream[cur_int + 1]);
- return lower | upper << (sizeof(unsigned) * CHAR_BIT - cur_bit);
- }
- else
- return grab_bits(cur_bit, how_many_bits, bitstream[cur_int]);
-}
-
-bool vl_bitstream_parser_init(struct vl_bitstream_parser *parser,
- unsigned num_bitstreams,
- const void **bitstreams,
- const unsigned *sizes)
-{
- assert(parser);
- assert(num_bitstreams);
- assert(bitstreams);
- assert(sizes);
-
- parser->num_bitstreams = num_bitstreams;
- parser->bitstreams = (const unsigned**)bitstreams;
- parser->sizes = sizes;
- parser->cur_bitstream = 0;
- parser->cursor = 0;
-
- return true;
-}
-
-void vl_bitstream_parser_cleanup(struct vl_bitstream_parser *parser)
-{
- assert(parser);
-}
-
-unsigned
-vl_bitstream_parser_get_bits(struct vl_bitstream_parser *parser,
- unsigned how_many_bits)
-{
- unsigned bits;
-
- assert(parser);
-
- bits = vl_bitstream_parser_show_bits(parser, how_many_bits);
-
- vl_bitstream_parser_forward(parser, how_many_bits);
-
- return bits;
-}
-
-unsigned
-vl_bitstream_parser_show_bits(struct vl_bitstream_parser *parser,
- unsigned how_many_bits)
-{
- unsigned bits = 0;
- unsigned shift = 0;
- unsigned cursor;
- unsigned cur_bitstream;
-
- assert(parser);
-
- cursor = parser->cursor;
- cur_bitstream = parser->cur_bitstream;
-
- while (1) {
- unsigned bits_left = parser->sizes[cur_bitstream] * CHAR_BIT - cursor;
- unsigned bits_to_show = how_many_bits > bits_left ? bits_left : how_many_bits;
-
- bits |= show_bits(cursor, bits_to_show,
- parser->bitstreams[cur_bitstream]) << shift;
-
- if (how_many_bits > bits_to_show) {
- how_many_bits -= bits_to_show;
- cursor = 0;
- ++cur_bitstream;
- shift += bits_to_show;
- }
- else
- break;
- }
-
- return bits;
-}
-
-void vl_bitstream_parser_forward(struct vl_bitstream_parser *parser,
- unsigned how_many_bits)
-{
- assert(parser);
- assert(how_many_bits);
-
- parser->cursor += how_many_bits;
-
- while (parser->cursor > parser->sizes[parser->cur_bitstream] * CHAR_BIT) {
- parser->cursor -= parser->sizes[parser->cur_bitstream++] * CHAR_BIT;
- assert(parser->cur_bitstream < parser->num_bitstreams);
- }
-}
-
-void vl_bitstream_parser_rewind(struct vl_bitstream_parser *parser,
- unsigned how_many_bits)
-{
- signed c;
-
- assert(parser);
- assert(how_many_bits);
-
- c = parser->cursor - how_many_bits;
-
- while (c < 0) {
- c += parser->sizes[parser->cur_bitstream--] * CHAR_BIT;
- assert(parser->cur_bitstream < parser->num_bitstreams);
- }
-
- parser->cursor = (unsigned)c;
-}
+++ /dev/null
-/**************************************************************************
- *
- * Copyright 2009 Younes Manton.
- * 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.
- *
- **************************************************************************/
-
-#ifndef vl_bitstream_parser_h
-#define vl_bitstream_parser_h
-
-#include "pipe/p_compiler.h"
-
-struct vl_bitstream_parser
-{
- unsigned num_bitstreams;
- const unsigned **bitstreams;
- const unsigned *sizes;
- unsigned cur_bitstream;
- unsigned cursor;
-};
-
-inline void endian_swap_ushort(unsigned short *x);
-inline void endian_swap_uint(unsigned int *x);
-inline void endian_swap_ulonglong(unsigned long long *x);
-
-bool vl_bitstream_parser_init(struct vl_bitstream_parser *parser,
- unsigned num_bitstreams,
- const void **bitstreams,
- const unsigned *sizes);
-
-void vl_bitstream_parser_cleanup(struct vl_bitstream_parser *parser);
-
-unsigned
-vl_bitstream_parser_get_bits(struct vl_bitstream_parser *parser,
- unsigned how_many_bits);
-
-unsigned
-vl_bitstream_parser_show_bits(struct vl_bitstream_parser *parser,
- unsigned how_many_bits);
-
-void vl_bitstream_parser_forward(struct vl_bitstream_parser *parser,
- unsigned how_many_bits);
-
-void vl_bitstream_parser_rewind(struct vl_bitstream_parser *parser,
- unsigned how_many_bits);
-
-#endif /* vl_bitstream_parser_h */
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