initial commit, 4.5 stable

thirdparty/libtheora/bitpack.h

@@ -0,0 +1,76 @@
+/********************************************************************
+ *                                                                  *
+ * THIS FILE IS PART OF THE OggTheora SOFTWARE CODEC SOURCE CODE.   *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
+ *                                                                  *
+ * THE OggTheora SOURCE CODE IS (C) COPYRIGHT 1994-2009             *
+ * by the Xiph.Org Foundation and contributors                      *
+ * https://www.xiph.org/                                            *
+ *                                                                  *
+ ********************************************************************
+
+  function: packing variable sized words into an octet stream
+
+ ********************************************************************/
+#if !defined(_bitpack_H)
+# define _bitpack_H (1)
+# include <stddef.h>
+# include <limits.h>
+# include "internal.h"
+
+
+
+typedef size_t             oc_pb_window;
+typedef struct oc_pack_buf oc_pack_buf;
+
+
+
+/*Custom bitpacker implementations.*/
+# if defined(OC_ARM_ASM)
+#  include "arm/armbits.h"
+# endif
+
+# if !defined(oc_pack_read)
+#  define oc_pack_read oc_pack_read_c
+# endif
+# if !defined(oc_pack_read1)
+#  define oc_pack_read1 oc_pack_read1_c
+# endif
+# if !defined(oc_huff_token_decode)
+#  define oc_huff_token_decode oc_huff_token_decode_c
+# endif
+
+# define OC_PB_WINDOW_SIZE ((int)sizeof(oc_pb_window)*CHAR_BIT)
+/*This is meant to be a large, positive constant that can still be efficiently
+   loaded as an immediate (on platforms like ARM, for example).
+  Even relatively modest values like 100 would work fine.*/
+# define OC_LOTS_OF_BITS (0x40000000)
+
+
+
+struct oc_pack_buf{
+  const unsigned char *stop;
+  const unsigned char *ptr;
+  oc_pb_window         window;
+  int                  bits;
+  int                  eof;
+};
+
+void oc_pack_readinit(oc_pack_buf *_b,unsigned char *_buf,long _bytes);
+int oc_pack_look1(oc_pack_buf *_b);
+void oc_pack_adv1(oc_pack_buf *_b);
+/*Here we assume 0<=_bits&&_bits<=32.*/
+long oc_pack_read_c(oc_pack_buf *_b,int _bits);
+int oc_pack_read1_c(oc_pack_buf *_b);
+/* returns -1 for read beyond EOF, or the number of whole bytes available */
+long oc_pack_bytes_left(oc_pack_buf *_b);
+
+/*These two functions are implemented locally in huffdec.c*/
+/*Read in bits without advancing the bitptr.
+  Here we assume 0<=_bits&&_bits<=32.*/
+/*static int oc_pack_look(oc_pack_buf *_b,int _bits);*/
+/*static void oc_pack_adv(oc_pack_buf *_b,int _bits);*/
+
+#endif