--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.6pre17/src/spandsp/private/v42bis.h	Fri Jun 25 15:50:58 2010 +0200
@@ -0,0 +1,151 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * private/v42bis.h
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2005 Steve Underwood
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: v42bis.h,v 1.1 2008/11/15 14:43:08 steveu Exp $
+ */
+
+#if !defined(_SPANDSP_PRIVATE_V42BIS_H_)
+#define _SPANDSP_PRIVATE_V42BIS_H_
+
+/*!
+    V.42bis dictionary node.
+*/
+typedef struct
+{
+    /*! \brief The prior code for each defined code. */
+    uint16_t parent_code;
+    /*! \brief The number of leaf nodes this node has */
+    int16_t leaves;
+    /*! \brief This leaf octet for each defined code. */
+    uint8_t node_octet;
+    /*! \brief Bit map of the children which exist */
+    uint32_t children[8];
+} v42bis_dict_node_t;
+
+/*!
+    V.42bis compression. This defines the working state for a single instance
+    of V.42bis compression.
+*/
+typedef struct
+{
+    /*! \brief Compression mode. */
+    int compression_mode;
+    /*! \brief Callback function to handle received frames. */
+    v42bis_frame_handler_t handler;
+    /*! \brief An opaque pointer passed in calls to frame_handler. */
+    void *user_data;
+    /*! \brief The maximum frame length allowed */
+    int max_len;
+
+    uint32_t string_code;
+    uint32_t latest_code;
+    int string_length;
+    uint32_t output_bit_buffer;
+    int output_bit_count;
+    int output_octet_count;
+    uint8_t output_buf[1024];
+    v42bis_dict_node_t dict[V42BIS_MAX_CODEWORDS];
+    /*! \brief TRUE if we are in transparent (i.e. uncompressable) mode */
+    int transparent;
+    int change_transparency;
+    /*! \brief IIR filter state, used in assessing compressibility. */
+    int compressibility_filter;
+    int compressibility_persistence;
+    
+    /*! \brief Next empty dictionary entry */
+    uint32_t v42bis_parm_c1;
+    /*! \brief Current codeword size */
+    int v42bis_parm_c2;
+    /*! \brief Threshold for codeword size change */
+    uint32_t v42bis_parm_c3;
+
+    /*! \brief Mark that this is the first octet/code to be processed */
+    int first;
+    uint8_t escape_code;
+} v42bis_compress_state_t;
+
+/*!
+    V.42bis decompression. This defines the working state for a single instance
+    of V.42bis decompression.
+*/
+typedef struct
+{
+    /*! \brief Callback function to handle decompressed data. */
+    v42bis_data_handler_t handler;
+    /*! \brief An opaque pointer passed in calls to data_handler. */
+    void *user_data;
+    /*! \brief The maximum decompressed data block length allowed */
+    int max_len;
+
+    uint32_t old_code;
+    uint32_t last_old_code;
+    uint32_t input_bit_buffer;
+    int input_bit_count;
+    int octet;
+    int last_length;
+    int output_octet_count;
+    uint8_t output_buf[1024];
+    v42bis_dict_node_t dict[V42BIS_MAX_CODEWORDS];
+    /*! \brief TRUE if we are in transparent (i.e. uncompressable) mode */
+    int transparent;
+
+    int last_extra_octet;
+
+    /*! \brief Next empty dictionary entry */
+    uint32_t v42bis_parm_c1;
+    /*! \brief Current codeword size */
+    int v42bis_parm_c2;
+    /*! \brief Threshold for codeword size change */
+    uint32_t v42bis_parm_c3;
+        
+    /*! \brief Mark that this is the first octet/code to be processed */
+    int first;
+    uint8_t escape_code;
+    int escaped;
+} v42bis_decompress_state_t;
+
+/*!
+    V.42bis compression/decompression descriptor. This defines the working state for a
+    single instance of V.42bis compress/decompression.
+*/
+struct v42bis_state_s
+{
+    /*! \brief V.42bis data compression directions. */
+    int v42bis_parm_p0;
+
+    /*! \brief Compression state. */
+    v42bis_compress_state_t compress;
+    /*! \brief Decompression state. */
+    v42bis_decompress_state_t decompress;
+    
+    /*! \brief Maximum codeword size (bits) */
+    int v42bis_parm_n1;
+    /*! \brief Total number of codewords */
+    uint32_t v42bis_parm_n2;
+    /*! \brief Maximum string length */
+    int v42bis_parm_n7;
+};
+
+#endif
+/*- End of file ------------------------------------------------------------*/