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- /*--------------------------------------------------------------------*/
- /* u l i b . c */
- /* */
- /* Serial port interface to COMMFIFO.ASM for MS-DOS */
- /*--------------------------------------------------------------------*/
-
- /*--------------------------------------------------------------------*/
- /* Changes Copyright (c) 1989 by Andrew H. Derbyshire. Changes */
- /* Copyright (c) 1990-1992 by Kendra Electronic Wonderworks; */
- /* all rights reserved except those explicitly granted by the */
- /* UUPC/extended license. */
- /*--------------------------------------------------------------------*/
-
- /*
- * $Id: ULIB.C 1.5 1992/12/12 16:12:13 ahd Exp $
- *
- * $Log: ULIB.C $
- * Revision 1.5 1992/12/12 16:12:13 ahd
- * Include header file for definition for memory avail routines
- *
- * Revision 1.4 1992/12/07 02:43:20 ahd
- * Improve error message when low memory prevents COMM port install
- *
- * Revision 1.3 1992/11/29 22:09:10 ahd
- * Use sopen() rather than FOPEN() to avoid retries on comm port
- *
- * Revision 1.2 1992/11/21 06:17:42 ahd
- * Delete old (pre-COMMFIFO) autobaud function
- *
- */
-
- /*--------------------------------------------------------------------*/
- /* System include files */
- /*--------------------------------------------------------------------*/
-
- #include <fcntl.h>
- #include <io.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <time.h>
- #include <share.h>
-
- #ifdef __TURBOC__
- #include <alloc.h>
- #endif
-
- /*--------------------------------------------------------------------*/
- /* UUPC/extended include files */
- /*--------------------------------------------------------------------*/
-
- #include "lib.h"
- #include "hlib.h"
- #include "ulib.h"
- #include "comm.h"
- #include "ssleep.h"
- #include "catcher.h"
-
- /*--------------------------------------------------------------------*/
- /* Internal prototypes */
- /*--------------------------------------------------------------------*/
-
- static void ShowModem( void );
-
- /*--------------------------------------------------------------------*/
- /* Global variables */
- /*--------------------------------------------------------------------*/
-
- boolean port_active = FALSE; /* TRUE = port handler handler active */
-
- static BPS current_bps;
- static char current_direct;
- static boolean carrierdetect;
-
- currentfile();
-
- /* IBM-PC I/O routines */
-
- /* "DCP" a uucp clone. Copyright Richard H. Lamb 1985,1986,1987 */
-
- /*************** BASIC I/O ***************************/
- /* Saltzers serial package (aka Info-IBMPC COM_PKG2):
- * Some notes: When packets are flying in both directions, there seems to
- * be some interrupt handling problems as far as receiving. Checksum errors
- * may therefore occur often even though we recover from them. This is
- * especially true with sliding windows. Errors are very few in the VMS
- * version. RH Lamb
- */
-
-
- #define STOPBIT 1
- #define LINELOG "LineData.Log" /* log serial line data here */
-
- static int log_handle;
- static int logmode = 0; /* Not yet logging */
- #define WRITING 1
- #define READING 2
- static FILE *log_stream;
- static int com_handle;
- static boolean hangup_needed = TRUE;
-
- /*--------------------------------------------------------------------*/
- /* o p e n l i n e */
- /* */
- /* Open the serial port for I/O */
- /*--------------------------------------------------------------------*/
-
- int openline(char *name, BPS bps, const boolean direct)
- {
- int value;
-
- if (port_active) /* Was the port already active? ahd */
- closeline(); /* Yes --> Shutdown it before open ahd */
-
- printmsg(15, "openline: %s, %d", name, bps);
-
- logmode = 0;
-
- current_direct = (char) (direct ? 'D' : 'M') ;
-
- if (sscanf(name, "COM%d", &value) != 1)
- {
- printmsg(0,"Communications port must be format COMx, was %s",
- name);
- panic();
- }
-
- norecovery = FALSE;
-
- com_handle = sopen( name, O_BINARY | O_RDWR, SH_DENYRW );
- /* Used soly for lock abilities */
- if ( com_handle == -1 )
- {
- printerr( name );
- return 1;
- }
-
- select_port(value);
- save_com();
-
- if (!install_com())
- {
- printmsg(0,"Commuications handler install failed; "
- "probable cause ... memory shortage.");
-
- #ifdef __TURBOC__
- printmsg(0,"FAR DOS Memory free = %ld bytes",
- farcoreleft() );
- #endif
-
- return 1;
- }
-
- open_com(bps, current_direct, 'N', STOPBIT, 'D');
- current_bps = bps;
- dtr_on();
- ssleep(2); /* Wait two seconds as required by V.24 */
- carrierdetect = FALSE; /* No modem connected yet */
-
- /*--------------------------------------------------------------------*/
- /* Log serial line data only if log file already exists */
- /*--------------------------------------------------------------------*/
-
- log_handle = open(LINELOG, O_WRONLY | O_TRUNC | O_BINARY);
- if (log_handle != -1) {
- printmsg(15, "openline: logging serial line data to %s", LINELOG);
- log_stream = fdopen(log_handle, "wb");
- }
-
- port_active = TRUE; /* record status for error handler */
-
- return 0;
-
- } /*openline*/
-
-
- /*--------------------------------------------------------------------*/
- /* s r e a d */
- /* */
- /* Read from the serial port */
- /* */
- /* Non-blocking read essential to "g" protocol. See */
- /* "dcpgpkt.c" for description. This all changes in a */
- /* multi-tasking system. Requests for I/O should get queued */
- /* and an event flag given. Then the requesting process (e.g. */
- /* gmachine()) waits for the event flag to fire processing */
- /* either a read or a write. Could be implemented on VAX/VMS */
- /* or DG but not MS-DOS. */
- /*--------------------------------------------------------------------*/
-
- unsigned int sread(char *buffer, unsigned int wanted, unsigned int timeout)
- {
- time_t start;
-
- hangup_needed = TRUE;
-
- start = time(nil(time_t)); /* Remember when we started processing */
-
- /*--------------------------------------------------------------------*/
- /* Report the current modem status */
- /*--------------------------------------------------------------------*/
-
- ShowModem();
-
- /*--------------------------------------------------------------------*/
- /* Now actually try to read a buffer of data */
- /*--------------------------------------------------------------------*/
-
- for ( ; ; )
- {
- unsigned int pending;
- pending = r_count_pending();
-
- if ( terminate_processing )
- {
- static boolean recurse = FALSE;
- if ( ! recurse )
- {
- printmsg(2,"sread: User aborted processing");
- recurse = TRUE;
- }
- return 0;
- }
-
- printmsg(20, "sread: pending=%d, wanted=%d", pending, wanted);
-
- if (pending >= wanted) { /* got enough in the buffer? */
- unsigned int i;
- for (i = 0; i < wanted; i++)
- *buffer++ = (char) receive_com();
-
- if (log_handle != -1)
- {
- #ifdef VERBOSE
- char s[18];
- #endif
- buffer -= wanted;
- if (logmode != READING)
- {
- fputs("\nRead: ", log_stream);
- logmode = READING;
- } /* if */
- #ifdef VERBOSE
- for (i = 0; i < wanted; i++) {
- itoa(0x100 | (unsigned) *buffer++, s, 16);
- /* Make it printable hex */
- fwrite(s, 1, 2, log_stream); /* Write hex to the log */
- } /* for */
- #else
- fwrite(buffer, 1, wanted, log_stream);
- /* Write data to the log */
- #endif
- } /* if (log_handle != -1) */
-
- return pending;
- } else {
- time_t now = time(nil(time_t));
- time_t elapsed = now - start;
-
- if (elapsed >= (long) timeout)
- return pending;
-
- ddelay(0); /* Surrender our time slice */
-
- } /* else */
- } /* for ( ; ; ) */
-
- } /*sread*/
-
- /*--------------------------------------------------------------------*/
- /* s w r i t e */
- /* */
- /* Write to the serial port */
- /*--------------------------------------------------------------------*/
-
- int swrite(char *data, unsigned int len)
- {
- unsigned int i;
-
- hangup_needed = TRUE;
-
- /*--------------------------------------------------------------------*/
- /* Report our modem status */
- /*--------------------------------------------------------------------*/
-
- ShowModem();
-
- /*--------------------------------------------------------------------*/
- /* Introduce a little flow control - Actual line pacing is */
- /* handled at a lower level */
- /*--------------------------------------------------------------------*/
-
- if ( s_count_free() < (int) len )
- {
- int spin = 0;
- static int const max_spin = 20;
-
- int queue_size = s_count_size();
- int queue_free = s_count_free();
-
- if ( len > queue_size )
- {
- printmsg(0,"swrite: Transmit buffer overflow; buffer size %d, "
- "needed %d",
- queue_size,len);
- panic();
- }
-
- while( (len > queue_free) && (spin < max_spin) )
- {
- int wait;
- int needed;
- int new_free;
-
- needed = max(queue_size/2, len-queue_free);
- /* Minimize thrashing by requiring
- big chunks */
-
- wait = (int) ((long) needed * 10000L / (long) current_bps);
- /* Compute time in milliseconds
- assuming 10 bits per byte */
-
- printmsg(4,"swrite: Waiting %d milliseconds for %d bytes in queue"
- ", pass %d",
- wait, needed, spin);
-
- ddelay( wait ); /* Actually perform the wait */
-
- new_free = s_count_free();
-
- if ( new_free == queue_free )
- spin++; /* No progress, consider timing out */
- else
- queue_free = new_free;
- /* Update our progress */
-
- } /* while( (len > queue_free) && spin ) */
-
- if ( queue_free < len )
- {
- printmsg(0,"swrite: Transmit buffer overflow, needed %d bytes",
- len);
- } /* if ( queue_free < len ) */
- return 0;
-
- } /* if ( s_count_free() < len ) */
-
- /*--------------------------------------------------------------------*/
- /* Send the data to the communications package */
- /*--------------------------------------------------------------------*/
-
- for (i = 0; i < len; i++)
- send_com(*data++);
-
- /*--------------------------------------------------------------------*/
- /* Log the transmitted data, if desired */
- /*--------------------------------------------------------------------*/
-
- if (log_handle != -1) {
- #ifdef VERBOSE
- char s[18];
- #endif
- if (logmode != WRITING)
- {
- fputs("\nWrite: ", log_stream);
- logmode = WRITING;
- } /* if */
- data -= len;
- #ifdef VERBOSE
- for (i = 0; i < len; i++) {
- itoa(0x100 | (unsigned) *data++, s, 16);
- /* Make it printable hex ahd */
- fwrite(s, 1, 2, log_stream);
- } /* for */
- #else
- fwrite(data, 1, len, log_stream); /* Write data to the log */
- #endif
- } /* if */
-
- /*--------------------------------------------------------------------*/
- /* Return byte count transmitted to caller */
- /*--------------------------------------------------------------------*/
-
- return len;
-
- } /*swrite*/
-
-
- /*--------------------------------------------------------------------*/
- /* s s e n d b r k */
- /* */
- /* Send a break signal out the serial port */
- /*--------------------------------------------------------------------*/
-
- void ssendbrk(unsigned int duration)
- {
-
- printmsg(12, "ssendbrk: %d", duration);
-
- break_com();
-
- } /*ssendbrk*/
-
-
- /*--------------------------------------------------------------------*/
- /* c l o s e l i n e */
- /* */
- /* Close the serial port down */
- /*--------------------------------------------------------------------*/
-
- void closeline(void)
- {
- int far *stats;
-
- if (!port_active)
- panic();
-
- port_active = FALSE; /* flag port closed for error handler */
-
- dtr_off();
- ddelay(500); /* Required for V.24 */
- close_com();
- restore_com();
- close( com_handle );
- norecovery = TRUE;
-
- if (log_handle != -1) { /* close serial line log file */
- fclose(log_stream);
- close(log_handle);
- };
-
- stats = com_errors();
- printmsg(3, "Buffer overflows: %-4d",stats[COM_EOVFLOW]);
- printmsg(3, "Receive overruns: %-4d", stats[COM_EOVRUN]);
- printmsg(3, "Break characters: %-4d", stats[COM_EBREAK]);
- printmsg(3, "Framing errors: %-4d", stats[COM_EFRAME]);
- printmsg(3, "Parity errors: %-4d", stats[COM_EPARITY]);
- printmsg(3, "Transmit errors: %-4d", stats[COM_EXMIT]);
- printmsg(3, "DSR errors: %-4d", stats[COM_EDSR]);
- printmsg(3, "CTS errors: %-4d", stats[COM_ECTS]);
-
- } /*closeline*/
-
-
- /*--------------------------------------------------------------------*/
- /* H a n g u p */
- /* */
- /* Hangup the telephone by dropping DTR. Works with HAYES and */
- /* many compatibles. */
- /* 14 May 89 Drew Derbyshire */
- /*--------------------------------------------------------------------*/
-
- void hangup( void )
- {
- if (!hangup_needed)
- return;
- hangup_needed = FALSE;
- dtr_off(); /* Hang the phone up */
- ddelay(500); /* Really only need 250 milliseconds */
- dtr_on(); /* Bring the modem back on-line */
- ddelay(2000); /* Now wait for the poor thing to recover */
- /* two seconds is required by V.24 */
- printmsg(3,"hangup: complete.");
- carrierdetect = FALSE; /* No modem connected yet */
-
- } /* hangup */
-
- /*--------------------------------------------------------------------*/
- /* S I O S p e e d */
- /* */
- /* Re-specify the speed of an opened serial port */
- /* */
- /* Dropped the DTR off/on calls because this makes a Hayes drop */
- /* the line if configured properly, and we don't want the modem */
- /* to drop the phone on the floor if we are performing */
- /* autobaud. */
- /* */
- /* (Configured properly = standard method of making a Hayes */
- /* hang up the telephone, especially when you can't get it into */
- /* command state because it is at the wrong speed or whatever.) */
- /*--------------------------------------------------------------------*/
-
- void SIOSpeed(BPS bps)
- {
-
- printmsg(4,"SIOSspeed: Changing port speed from %ld BPS to %ld BPS",
- (long) current_bps, (long) bps);
- ioctl_com(0, bps);
-
- ShowModem();
- current_bps = bps;
-
- } /*SIOSpeed*/
-
- /*--------------------------------------------------------------------*/
- /* f l o w c o n t r o l */
- /* */
- /* Enable/Disable in band (XON/XOFF) flow control */
- /*--------------------------------------------------------------------*/
-
- void flowcontrol( boolean flow )
- {
- printmsg(4,"flowcontrol: Closing port");
- close_com();
- ShowModem();
- printmsg(4,"flowcontrol: Opening port to %sable flow control",
- flow ? "en" : "dis");
- open_com(current_bps, current_direct, 'N', STOPBIT, flow ? 'E' : 'D');
- ShowModem();
-
- } /*flowcontrol*/
-
- /*--------------------------------------------------------------------*/
- /* G e t S p e e d */
- /* */
- /* Report current speed of communications connection */
- /*--------------------------------------------------------------------*/
-
- BPS GetSpeed( void )
- {
- return current_bps;
- } /* GetSpeed */
-
- /*--------------------------------------------------------------------*/
- /* C D */
- /* */
- /* Report if we have carrier detect and lost it */
- /*--------------------------------------------------------------------*/
-
- boolean CD( void )
- {
- boolean online = carrierdetect;
-
- ShowModem();
- carrierdetect = is_cd_high();
-
- /*--------------------------------------------------------------------*/
- /* If we previously had carrier detect but have lost it, we */
- /* report it was lost. If we do not yet have carrier detect, */
- /* we return success because we may not have connected yet. */
- /*--------------------------------------------------------------------*/
-
- if (online)
- return carrierdetect && is_dsr_high();
- else
- return is_dsr_high();
-
- } /* CD */
-
- /*--------------------------------------------------------------------*/
- /* S h o w M o d e m */
- /* */
- /* Report current modem status */
- /*--------------------------------------------------------------------*/
-
- #define mannounce(flag, bits, text ) ((flag & bits) ? text : "" )
-
- static void ShowModem( void )
- {
- static int old_status = 0xDEAD;
- int status;
-
- if ( debuglevel < 4 )
- return;
-
- status = modem_status();
- if (status == old_status)
- return;
-
- printmsg(0, "ShowModem: %#02x%s%s%s%s%s%s%s%s",
- status,
- mannounce(MDM_CD, status, "\tCarrier Detect"),
- mannounce(MDM_RI, status, "\tRing Indicator"),
- mannounce(MDM_DSR, status, "\tData Set Ready"),
- mannounce(MDM_CTS, status, "\tClear to Send"),
- mannounce(MDM_CDC, status, "\tCD changed"),
- mannounce(MDM_TRI, status, "\tRI went OFF"),
- mannounce(MDM_DSRC, status, "\tDSR changed"),
- mannounce(MDM_CTSC, status, "\tCTS changed"));
- old_status = status;
-
- } /* ShowModem */
-