Category : C Source Code
Archive   : V_RB_SB.ZIP
Filename : VVMODEM.C

/*
* VMODEM
* VMS support for UMODEM and vvrb/vvsb programs
*
* Defined herein are some utility routines to make the UNIX
* program UMODEM run under VAX/VMS C:
*
* assign_channel Calls the VMS System Service $ASSIGN
* to assign a channel to a device.
* The routine currently has the device
* "TT" hardwired into it.
* gtty Gets terminal characteristics, almost
* like the UNIX GTTY system call.
* filestat Returns the length of the file.
* raw_read Reads characters from the terminal
* without any echoing or interpretation
* and with an optional timeout period.
* raw_write Writes a character to the terminal
* without any interpretation.
* raw_wbuf Writes a buffer to the terminal
* without any interpretation.
* stty Sets terminal characteristics, almost
* like the UNIX STTY system call.
*
* Some of the ideas used here were obtained from code written
* by Max Benson and Robert Bruccoleri.
*
* Walter Reiher
* Harvard University
* Department of Chemistry
* 12 Oxford Street
* Cambridge, MA 02138
* March 11, 1983
*
* Modified 12-18-85 Chuck Forsberg, Omen Technology Inc
* 17505-V NW Sauvie IS RD Portland OR 97231 omen!caf
*/
#include descrip
#include iodef
#include rms
#include ssdef
#include stdio
#include "vmodem.h"

#define TRUE 1
#define FALSE 0

static char tt_name[] = "TT";
static short tt_chan = -1; /* Terminal channel number */

struct tt_io_iosb /* Terminal I/O IOSB */
{
short status;
short byte_count;
short terminator;
short terminator_size;
};

/*
* Terminator mask for PASSALL reads.
* Permits reads of all possible 8-bit characters.
*/
int t_mask[32] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0 };

struct terminator_mask {
short size ;
short unused ;
int *mask ;
}

termin_mask = { 32, 0, t_mask };

/*
* ASSIGN a channel to the logical name TT, which is usually
* the terminal.
*/
assign_channel()
{
int status;
$DESCRIPTOR(tt_descriptor, tt_name);

if (tt_chan == -1)
status = sys$assign(&tt_descriptor, &tt_chan, 0, 0);
else
status = SS$_NORMAL;

if (status != SS$_NORMAL || tt_chan == -1)
error("ASSIGN_CHANNEL: error in SYS$ASSIGN\n", FALSE);

return;
}

/*
* Gets terminal information from VMS.
*/
gtty(tt_characteristics)
struct tt_info *tt_characteristics;
{
int status;

if (tt_chan == -1)
assign_channel();

status = sys$qiow(0, tt_chan, IO$_SENSEMODE,
&(tt_characteristics->dev_modes), NULL, 0,
&(tt_characteristics->dev_characteristics), 12,
0, 0, 0, 0);
if (status != SS$_NORMAL ||
tt_characteristics->dev_modes.status != SS$_NORMAL)
error("GTTY: sense mode QIO error return.\n", FALSE);

return(status);
}

/*
* FILESTAT
* Provide FILE STATistics under VMS
*
* Opens the file and counts the bytes (GROSS!!)
* This appears to be the only to get the exact number, given
* all of RMS's permutations of file structure.
* Returns the number of bytes in the file, returns -1 on error.
*/
long filestat(name)
char *name;
{
FILE *fin;
long bytes = -1;

if (fin = fopen(name, "r")) {
while (++bytes, getc(fin) != EOF)
;
fclose(fin);
}
return bytes;
}



/*
* Read NCHAR characters from the terminal without echoing or
* interpretation.
* If the argument SECONDS is non-zero, use that as the
* timeout period in seconds for the read.
*
* NOTE THAT THIS FUNCTION RETURNS AN INT, NOT A CHAR!
* That is because of the possibility of a SS$_TIMEOUT return.
* Returns SS$_TIMEOUT in case of timeout or other error.
*/
int raw_read(nchar, charbuf, seconds)
char *charbuf;
int nchar;
unsigned seconds;
{
short function;
int status;
struct tt_io_iosb iosb;

if (tt_chan == -1)
assign_channel();

function = IO$_READVBLK | IO$M_NOECHO | IO$M_NOFILTR;

if (seconds)
status = sys$qiow(0, tt_chan, function | IO$M_TIMED,
&iosb, NULL, 0,
charbuf, nchar, seconds,
&termin_mask, NULL, 0);
else
status = sys$qiow(0, tt_chan, function,
&iosb, NULL, 0,
charbuf, nchar, 0,
&termin_mask, NULL, 0);

if (status == SS$_TIMEOUT || iosb.status == SS$_TIMEOUT)
return(SS$_TIMEOUT);
else if (status != SS$_NORMAL || iosb.status != SS$_NORMAL)
return(SS$_TIMEOUT);

return((int)*charbuf);
}

/*
* Writes a character to the terminal without echoing or
* interpretation.
*/
raw_write(c)
char c;
{
int status;
struct tt_io_iosb iosb;

if (tt_chan == -1)
assign_channel();

status = sys$qiow(0, tt_chan,
IO$_WRITEVBLK | IO$M_CANCTRLO | IO$M_NOFORMAT,
&iosb, NULL, 0,
&c, 1, 0, 0, 0, 0);

if (status != SS$_NORMAL || iosb.status != SS$_NORMAL)
error("RAW_WRITE: write QIO error return.\n", TRUE);

return;
}

/*
* Writes a buffer to the terminal without echoing or
* interpretation.
*/
raw_wbuf(nchar, charbuf)
char *charbuf;
int nchar;
{
int status;
struct tt_io_iosb iosb;

if (tt_chan == -1)
assign_channel();

status = sys$qiow(0, tt_chan,
IO$_WRITEVBLK | IO$M_CANCTRLO | IO$M_NOFORMAT,
&iosb, NULL, 0,
charbuf, nchar, 0, 0, 0, 0);

if (status != SS$_NORMAL || iosb.status != SS$_NORMAL)
error("RAW_WRITE: write QIO error return.\n", TRUE);

return;
}

/*
* Sets terminal information from VMS.
* Modified 12-85 Larry Farr/Chuck Forsberg to not use
* bad parity returned by VMS 4.
*/
stty(tt_characteristics)
struct tt_info *tt_characteristics;
{
short *f_ptr, /* *p_ptr, */ *s_ptr;
int status;
struct tt_mode_iosb iosb;

if (tt_chan == -1)
assign_channel();

/*
* We do the following in order to get a full short, concatenating
* two adjacent chars:
*/
s_ptr = &(tt_characteristics->dev_modes.t_speed); /* Speeds */
f_ptr = &(tt_characteristics->dev_modes.CR_fill); /* Fills */
/* p_ptr = &(tt_characteristics->dev_modes.parity_flags); */

status = sys$qiow(0, tt_chan, IO$_SETMODE,
&iosb, NULL, 0,
&(tt_characteristics->dev_characteristics), 12,
/* *s_ptr, *f_ptr, *p_ptr, 0); */
*s_ptr, *f_ptr, 0, 0);
if (status != SS$_NORMAL || iosb.status != SS$_NORMAL)
printf("STTY: set mode QIO returned %d\n", status);

return(status);
}