--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.6pre17/src/spandsp/private/hdlc.h	Fri Jun 25 15:50:58 2010 +0200
@@ -0,0 +1,140 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * private/hdlc.h
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2003 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: hdlc.h,v 1.3 2009/02/12 12:38:39 steveu Exp $
+ */
+
+#if !defined(_SPANDSP_PRIVATE_HDLC_H_)
+#define _SPANDSP_PRIVATE_HDLC_H_
+
+/*!
+    HDLC receive descriptor. This contains all the state information for an HDLC receiver.
+ */
+struct hdlc_rx_state_s
+{
+    /*! 2 for CRC-16, 4 for CRC-32 */
+    int crc_bytes;
+    /*! \brief Maximum permitted frame length. */
+    size_t max_frame_len;
+    /*! \brief The callback routine called to process each good received frame. */
+    hdlc_frame_handler_t frame_handler;
+    /*! \brief An opaque parameter passed to the frame callback routine. */
+    void *frame_user_data;
+    /*! \brief The callback routine called to report status changes. */
+    modem_rx_status_func_t status_handler;
+    /*! \brief An opaque parameter passed to the status callback routine. */
+    void *status_user_data;
+    /*! \brief TRUE if bad frames are to be reported. */
+    int report_bad_frames;
+    /*! \brief The number of consecutive flags which must be seen before framing is
+        declared OK. */
+    int framing_ok_threshold;
+    /*! \brief TRUE if framing OK has been announced. */
+    int framing_ok_announced;
+    /*! \brief Number of consecutive flags seen so far. */
+    int flags_seen;
+
+    /*! \brief The raw (stuffed) bit stream buffer. */
+    unsigned int raw_bit_stream;
+    /*! \brief The destuffed bit stream buffer. */
+    unsigned int byte_in_progress;
+    /*! \brief The current number of bits in byte_in_progress. */
+    int num_bits;
+    /*! \brief TRUE if in octet counting mode (e.g. for MTP). */
+    int octet_counting_mode;
+    /*! \brief Octet count, to achieve the functionality needed for things
+               like MTP. */
+    int octet_count;
+    /*! \brief The number of octets to be allowed between octet count reports. */
+    int octet_count_report_interval;
+
+    /*! \brief Buffer for a frame in progress. */
+    uint8_t buffer[HDLC_MAXFRAME_LEN + 4];
+    /*! \brief Length of a frame in progress. */
+    size_t len;
+
+    /*! \brief The number of bytes of good frames received (CRC not included). */
+    unsigned long int rx_bytes;
+    /*! \brief The number of good frames received. */
+    unsigned long int rx_frames;
+    /*! \brief The number of frames with CRC errors received. */
+    unsigned long int rx_crc_errors;
+    /*! \brief The number of too short and too long frames received. */
+    unsigned long int rx_length_errors;
+    /*! \brief The number of HDLC aborts received. */
+    unsigned long int rx_aborts;
+};
+
+/*!
+    HDLC transmit descriptor. This contains all the state information for an
+    HDLC transmitter.
+ */
+struct hdlc_tx_state_s
+{
+    /*! 2 for CRC-16, 4 for CRC-32 */
+    int crc_bytes;
+    /*! \brief The callback routine called to indicate transmit underflow. */
+    hdlc_underflow_handler_t underflow_handler;
+    /*! \brief An opaque parameter passed to the callback routine. */
+    void *user_data;
+    /*! \brief The minimum flag octets to insert between frames. */
+    int inter_frame_flags;
+    /*! \brief TRUE if frame creation works in progressive mode. */
+    int progressive;
+    /*! \brief Maximum permitted frame length. */
+    size_t max_frame_len;
+
+    /*! \brief The stuffed bit stream being created. */
+    uint32_t octets_in_progress;
+    /*! \brief The number of bits currently in octets_in_progress. */
+    int num_bits;
+    /*! \brief The currently rotated state of the flag octet. */
+    int idle_octet;
+    /*! \brief The number of flag octets to send for a timed burst of flags. */
+    int flag_octets;
+    /*! \brief The number of abort octets to send for a timed burst of aborts. */
+    int abort_octets;
+    /*! \brief TRUE if the next underflow of timed flag octets should be reported */
+    int report_flag_underflow;
+
+    /*! \brief The current message being transmitted, with its CRC attached. */
+    uint8_t buffer[HDLC_MAXFRAME_LEN + 4];
+    /*! \brief The length of the message in the buffer. */
+    size_t len;
+    /*! \brief The current send position within the buffer. */
+    size_t pos;
+    /*! \brief The running CRC, as data fills the frame buffer. */
+    uint32_t crc;
+
+    /*! \brief The current byte being broken into bits for transmission. */
+    int byte;
+    /*! \brief The number of bits remaining in byte. */
+    int bits;
+    
+    /*! \brief TRUE if transmission should end on buffer underflow .*/
+    int tx_end;
+};
+
+#endif
+/*- End of file ------------------------------------------------------------*/