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Comand CMD_HDLC_FRAMING_IDLE will poll if encoder is idle (has finnished typ.)

This commit is contained in:
Morten Rolland 1999-07-01 14:24:48 +00:00
parent 780d309b3d
commit 1b6a12cab6
2 changed files with 28 additions and 4 deletions
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3
include/ifax/modules/hdlc-framing.h
View File

@ -26,6 +26,7 @@
******************************************************************************
*/
#define CMD_FRAMING_HDLC_TXFRAME 0x01
#define CMD_HDLC_FRAMING_TXFRAME 0x01
#define CMD_HDLC_FRAMING_IDLE 0x02
int encoder_hdlc_construct(ifax_modp self, va_list args);

29
modules/hdlc-framing.c
View File

@ -2,7 +2,7 @@
******************************************************************************
Fax program for ISDN.
Encoder and decoder for HDLC-framing.
Encoder for HDLC-framing.
Copyright (C) 1999 Morten Rolland [Morten.Rolland@asker.mail.telia.com]
@ -62,6 +62,7 @@ typedef struct {
int new_frame;
int current_frame;
int idle, idlebits;
struct {
size_t size;
@ -455,12 +456,20 @@ void produce_bits(encoder_hdlc_private *priv)
if ( priv->phase == IDLE ) {
/* Send idle-FLAGS, and possibly initiate a new transfer */
if ( !priv->idle ) {
/* We may go idle in a few bits time, prepare for this */
priv->idle = 1;
priv->idlebits = -8 - priv->bitslide_size;
}
if ( priv->current_frame != priv->new_frame ) {
/* There is a frame queued up, prepare for its transmission */
priv->phase = ADDRESS;
priv->fcs = 0xffff;
priv->src = &priv->framequeue[priv->current_frame].address;
priv->remaining_bytes = 1;
priv->idle = 0;
}
/* Transmit a FLAG-sequence, no bit-stuffing applied. This flag is
* either an idle-channel pattern, or the initial flag of a frame.
@ -479,25 +488,28 @@ void produce_bits(encoder_hdlc_private *priv)
/* Advance to next phase if current phase exhausted */
if ( priv->remaining_bytes == 0 ) {
switch ( priv->phase ) {
case ADDRESS:
priv->phase = PAYLOAD;
priv->src = priv->framequeue[priv->current_frame].start;
priv->remaining_bytes = priv->framequeue[priv->current_frame].size;
break;
case PAYLOAD:
priv->phase = FCS;
priv->src = &priv->fcs_tx[0];
priv->remaining_bytes = 2;
priv->fcs_tx[0] = ~(priv->fcs & 0xff);
priv->fcs_tx[1] = ~((priv->fcs>>8) & 0xff);
break;
case FCS:
priv->phase = IDLE;
priv->current_frame++;
if ( priv->current_frame >= QUEUESIZE )
priv->current_frame = 0;
break;
case IDLE:
/* Should never get here, but these lines removes a compile warning */
break;
@ -585,6 +597,7 @@ void encoder_hdlc_demand(ifax_modp self, size_t demand)
*dst++ = priv->bitslide & 0xff;
priv->bitslide >>= 8;
priv->bitslide_size -= 8;
priv->idlebits += 8;
}
}
@ -598,6 +611,7 @@ void encoder_hdlc_demand(ifax_modp self, size_t demand)
*dst++ = priv->bitslide & 0xff;
priv->bitslide >>= do_bits;
priv->bitslide_size -= do_bits;
priv->idlebits += do_bits;
chunk_bits += do_bits;
remaining_bits -= do_bits;
}
@ -623,6 +637,7 @@ static void tx_frame(encoder_hdlc_private *priv, ifax_uint8 *start,
priv->framequeue[priv->new_frame].start = start;
priv->framequeue[priv->new_frame].address = address;
priv->new_frame++;
priv->idle = 0;
if ( priv->new_frame >= QUEUESIZE )
priv->new_frame = 0;
}
@ -635,12 +650,18 @@ int encoder_hdlc_command(ifax_modp self, int cmd, va_list cmds)
switch ( cmd ) {
case CMD_FRAMING_HDLC_TXFRAME:
case CMD_HDLC_FRAMING_TXFRAME:
frame_start = va_arg(cmds,ifax_uint8 *);
frame_size = va_arg(cmds,int);
address = va_arg(cmds,ifax_uint8);
tx_frame(priv,frame_start,frame_size,address);
break;
case CMD_HDLC_FRAMING_IDLE:
if ( priv->idle && priv->idlebits > 0 )
return priv->idlebits;
return 0;
break;
}
return 0;
@ -668,6 +689,8 @@ int encoder_hdlc_construct(ifax_modp self,va_list args)
priv->phase = IDLE;
priv->new_frame = 0;
priv->current_frame = 0;
priv->idle = 1;
priv->idlebits = 1;
return 0;
}