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diff --git a/utils/rbutilqt/mspack/qtm.h b/utils/rbutilqt/mspack/qtm.h
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+/* This file is part of libmspack.
+ * (C) 2003-2004 Stuart Caie.
+ *
+ * The Quantum method was created by David Stafford, adapted by Microsoft
+ * Corporation.
+ *
+ * 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_QTM_H
+#define MSPACK_QTM_H 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Quantum compression / decompression definitions */
+
+#define QTM_FRAME_SIZE (32768)
+
+struct qtmd_modelsym {
+ unsigned short sym, cumfreq;
+};
+
+struct qtmd_model {
+ int shiftsleft, entries;
+ struct qtmd_modelsym *syms;
+};
+
+struct qtmd_stream {
+ struct mspack_system *sys; /* I/O routines */
+ struct mspack_file *input; /* input file handle */
+ struct mspack_file *output; /* output file handle */
+
+ unsigned char *window; /* decoding window */
+ unsigned int window_size; /* window size */
+ unsigned int window_posn; /* decompression offset within window */
+ unsigned int frame_todo; /* bytes remaining for current frame */
+
+ unsigned short H, L, C; /* high/low/current: arith coding state */
+ unsigned char header_read; /* have we started decoding a new frame? */
+
+ int error;
+
+ /* I/O buffers */
+ unsigned char *inbuf, *i_ptr, *i_end, *o_ptr, *o_end;
+ unsigned int bit_buffer, inbuf_size;
+ unsigned char bits_left, input_end;
+
+ /* four literal models, each representing 64 symbols
+ * model0 for literals from 0 to 63 (selector = 0)
+ * model1 for literals from 64 to 127 (selector = 1)
+ * model2 for literals from 128 to 191 (selector = 2)
+ * model3 for literals from 129 to 255 (selector = 3) */
+ struct qtmd_model model0, model1, model2, model3;
+
+ /* three match models.
+ * model4 for match with fixed length of 3 bytes
+ * model5 for match with fixed length of 4 bytes
+ * model6 for variable length match, encoded with model6len model */
+ struct qtmd_model model4, model5, model6, model6len;
+
+ /* selector model. 0-6 to say literal (0,1,2,3) or match (4,5,6) */
+ struct qtmd_model model7;
+
+ /* symbol arrays for all models */
+ struct qtmd_modelsym m0sym[64 + 1];
+ struct qtmd_modelsym m1sym[64 + 1];
+ struct qtmd_modelsym m2sym[64 + 1];
+ struct qtmd_modelsym m3sym[64 + 1];
+ struct qtmd_modelsym m4sym[24 + 1];
+ struct qtmd_modelsym m5sym[36 + 1];
+ struct qtmd_modelsym m6sym[42 + 1], m6lsym[27 + 1];
+ struct qtmd_modelsym m7sym[7 + 1];
+};
+
+/* allocates Quantum decompression state for decoding the given stream.
+ *
+ * - returns NULL if window_bits is outwith the range 10 to 21 (inclusive).
+ *
+ * - uses system->alloc() to allocate memory
+ *
+ * - returns NULL if not enough memory
+ *
+ * - window_bits is the size of the Quantum window, from 1Kb (10) to 2Mb (21).
+ *
+ * - input_buffer_size is the number of bytes to use to store bitstream data.
+ */
+extern struct qtmd_stream *qtmd_init(struct mspack_system *system,
+ struct mspack_file *input,
+ struct mspack_file *output,
+ int window_bits,
+ int input_buffer_size);
+
+/* decompresses, or decompresses more of, a Quantum stream.
+ *
+ * - out_bytes of data will be decompressed and the function will return
+ * with an MSPACK_ERR_OK return code.
+ *
+ * - decompressing will stop as soon as out_bytes is reached. if the true
+ * amount of bytes decoded spills over that amount, they will be kept for
+ * a later invocation of qtmd_decompress().
+ *
+ * - the output bytes will be passed to the system->write() function given in
+ * qtmd_init(), using the output file handle given in qtmd_init(). More
+ * than one call may be made to system->write()
+ *
+ * - Quantum will read input bytes as necessary using the system->read()
+ * function given in qtmd_init(), using the input file handle given in
+ * qtmd_init(). This will continue until system->read() returns 0 bytes,
+ * or an error.
+ */
+extern int qtmd_decompress(struct qtmd_stream *qtm, off_t out_bytes);
+
+/* frees all state associated with a Quantum data stream
+ *
+ * - calls system->free() using the system pointer given in qtmd_init()
+ */
+void qtmd_free(struct qtmd_stream *qtm);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif