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diff --git a/utils/rbutilqt/mspack/readbits.h b/utils/rbutilqt/mspack/readbits.h
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+/* This file is part of libmspack.
+ * (C) 2003-2010 Stuart Caie.
+ *
+ * libmspack is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU Lesser General Public License (LGPL) version 2.1
+ *
+ * For further details, see the file COPYING.LIB distributed with libmspack
+ */
+
+#ifndef MSPACK_READBITS_H
+#define MSPACK_READBITS_H 1
+
+/* this header defines macros that read data streams by
+ * the individual bits
+ *
+ * INIT_BITS initialises bitstream state in state structure
+ * STORE_BITS stores bitstream state in state structure
+ * RESTORE_BITS restores bitstream state from state structure
+ * ENSURE_BITS(n) ensure there are at least N bits in the bit buffer
+ * READ_BITS(var,n) takes N bits from the buffer and puts them in var
+ * PEEK_BITS(n) extracts without removing N bits from the bit buffer
+ * REMOVE_BITS(n) removes N bits from the bit buffer
+ *
+ * READ_BITS simply calls ENSURE_BITS, PEEK_BITS and REMOVE_BITS,
+ * which means it's limited to reading the number of bits you can
+ * ensure at any one time. It also fails if asked to read zero bits.
+ * If you need to read zero bits, or more bits than can be ensured in
+ * one go, use READ_MANY_BITS instead.
+ *
+ * These macros have variable names baked into them, so to use them
+ * you have to define some macros:
+ * - BITS_TYPE: the type name of your state structure
+ * - BITS_VAR: the variable that points to your state structure
+ * - define BITS_ORDER_MSB if bits are read from the MSB, or
+ * define BITS_ORDER_LSB if bits are read from the LSB
+ * - READ_BYTES: some code that reads more data into the bit buffer,
+ * it should use READ_IF_NEEDED (calls read_input if the byte buffer
+ * is empty), then INJECT_BITS(data,n) to put data from the byte
+ * buffer into the bit buffer.
+ *
+ * You also need to define some variables and structure members:
+ * - unsigned char *i_ptr; // current position in the byte buffer
+ * - unsigned char *i_end; // end of the byte buffer
+ * - unsigned int bit_buffer; // the bit buffer itself
+ * - unsigned int bits_left; // number of bits remaining
+ *
+ * If you use read_input() and READ_IF_NEEDED, they also expect these
+ * structure members:
+ * - struct mspack_system *sys; // to access sys->read()
+ * - unsigned int error; // to record/return read errors
+ * - unsigned char input_end; // to mark reaching the EOF
+ * - unsigned char *inbuf; // the input byte buffer
+ * - unsigned int inbuf_size; // the size of the input byte buffer
+ *
+ * Your READ_BYTES implementation should read data from *i_ptr and
+ * put them in the bit buffer. READ_IF_NEEDED will call read_input()
+ * if i_ptr reaches i_end, and will fill up inbuf and set i_ptr to
+ * the start of inbuf and i_end to the end of inbuf.
+ *
+ * If you're reading in MSB order, the routines work by using the area
+ * beyond the MSB and the LSB of the bit buffer as a free source of
+ * zeroes when shifting. This avoids having to mask any bits. So we
+ * have to know the bit width of the bit buffer variable. We use
+ * <limits.h> and CHAR_BIT to find the size of the bit buffer in bits.
+ *
+ * If you are reading in LSB order, bits need to be masked. Normally
+ * this is done by computing the mask: N bits are masked by the value
+ * (1<<N)-1). However, you can define BITS_LSB_TABLE to use a lookup
+ * table instead of computing this. This adds two new macros,
+ * PEEK_BITS_T and READ_BITS_T which work the same way as PEEK_BITS
+ * and READ_BITS, except they use this lookup table. This is useful if
+ * you need to look up a number of bits that are only known at
+ * runtime, so the bit mask can't be turned into a constant by the
+ * compiler.
+
+ * The bit buffer datatype should be at least 32 bits wide: it must be
+ * possible to ENSURE_BITS(17), so it must be possible to add 16 new bits
+ * to the bit buffer when the bit buffer already has 1 to 15 bits left.
+ */
+
+#ifndef BITS_VAR
+# error "define BITS_VAR as the state structure poiner variable name"
+#endif
+#ifndef BITS_TYPE
+# error "define BITS_TYPE as the state structure type"
+#endif
+#if defined(BITS_ORDER_MSB) && defined(BITS_ORDER_LSB)
+# error "you must define either BITS_ORDER_MSB or BITS_ORDER_LSB"
+#else
+# if !(defined(BITS_ORDER_MSB) || defined(BITS_ORDER_LSB))
+# error "you must define BITS_ORDER_MSB or BITS_ORDER_LSB"
+# endif
+#endif
+
+#if HAVE_LIMITS_H
+# include <limits.h>
+#endif
+#ifndef CHAR_BIT
+# define CHAR_BIT (8)
+#endif
+#define BITBUF_WIDTH (sizeof(bit_buffer) * CHAR_BIT)
+
+#define INIT_BITS do { \
+ BITS_VAR->i_ptr = &BITS_VAR->inbuf[0]; \
+ BITS_VAR->i_end = &BITS_VAR->inbuf[0]; \
+ BITS_VAR->bit_buffer = 0; \
+ BITS_VAR->bits_left = 0; \
+ BITS_VAR->input_end = 0; \
+} while (0)
+
+#define STORE_BITS do { \
+ BITS_VAR->i_ptr = i_ptr; \
+ BITS_VAR->i_end = i_end; \
+ BITS_VAR->bit_buffer = bit_buffer; \
+ BITS_VAR->bits_left = bits_left; \
+} while (0)
+
+#define RESTORE_BITS do { \
+ i_ptr = BITS_VAR->i_ptr; \
+ i_end = BITS_VAR->i_end; \
+ bit_buffer = BITS_VAR->bit_buffer; \
+ bits_left = BITS_VAR->bits_left; \
+} while (0)
+
+#define ENSURE_BITS(nbits) do { \
+ while (bits_left < (nbits)) READ_BYTES; \
+} while (0)
+
+#define READ_BITS(val, nbits) do { \
+ ENSURE_BITS(nbits); \
+ (val) = PEEK_BITS(nbits); \
+ REMOVE_BITS(nbits); \
+} while (0)
+
+#define READ_MANY_BITS(val, bits) do { \
+ unsigned char needed = (bits), bitrun; \
+ (val) = 0; \
+ while (needed > 0) { \
+ if (bits_left <= (BITBUF_WIDTH - 16)) READ_BYTES; \
+ bitrun = (bits_left < needed) ? bits_left : needed; \
+ (val) = ((val) << bitrun) | PEEK_BITS(bitrun); \
+ REMOVE_BITS(bitrun); \
+ needed -= bitrun; \
+ } \
+} while (0)
+
+#ifdef BITS_ORDER_MSB
+# define PEEK_BITS(nbits) (bit_buffer >> (BITBUF_WIDTH - (nbits)))
+# define REMOVE_BITS(nbits) ((bit_buffer <<= (nbits)), (bits_left -= (nbits)))
+# define INJECT_BITS(bitdata,nbits) ((bit_buffer |= \
+ (bitdata) << (BITBUF_WIDTH - (nbits) - bits_left)), (bits_left += (nbits)))
+#else /* BITS_ORDER_LSB */
+# define PEEK_BITS(nbits) (bit_buffer & ((1 << (nbits))-1))
+# define REMOVE_BITS(nbits) ((bit_buffer >>= (nbits)), (bits_left -= (nbits)))
+# define INJECT_BITS(bitdata,nbits) ((bit_buffer |= \
+ (bitdata) << bits_left), (bits_left += (nbits)))
+#endif
+
+#ifdef BITS_LSB_TABLE
+/* lsb_bit_mask[n] = (1 << n) - 1 */
+static const unsigned short lsb_bit_mask[17] = {
+ 0x0000, 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
+ 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
+};
+# define PEEK_BITS_T(nbits) (bit_buffer & lsb_bit_mask[(nbits)])
+# define READ_BITS_T(val, nbits) do { \
+ ENSURE_BITS(nbits); \
+ (val) = PEEK_BITS_T(nbits); \
+ REMOVE_BITS(nbits); \
+} while (0)
+#endif
+
+#ifndef BITS_NO_READ_INPUT
+# define READ_IF_NEEDED do { \
+ if (i_ptr >= i_end) { \
+ if (read_input(BITS_VAR)) \
+ return BITS_VAR->error; \
+ i_ptr = BITS_VAR->i_ptr; \
+ i_end = BITS_VAR->i_end; \
+ } \
+} while (0)
+
+static int read_input(BITS_TYPE *p) {
+ int read = p->sys->read(p->input, &p->inbuf[0], (int)p->inbuf_size);
+ if (read < 0) return p->error = MSPACK_ERR_READ;
+
+ /* we might overrun the input stream by asking for bits we don't use,
+ * so fake 2 more bytes at the end of input */
+ if (read == 0) {
+ if (p->input_end) {
+ D(("out of input bytes"))
+ return p->error = MSPACK_ERR_READ;
+ }
+ else {
+ read = 2;
+ p->inbuf[0] = p->inbuf[1] = 0;
+ p->input_end = 1;
+ }
+ }
+
+ /* update i_ptr and i_end */
+ p->i_ptr = &p->inbuf[0];
+ p->i_end = &p->inbuf[read];
+ return MSPACK_ERR_OK;
+}
+#endif
+#endif