direwolf/kiss.c

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Version 1.0 - Initial commit Changes to be committed: new file: .gitattributes new file: .gitignore new file: APRStt-Implementation-Notes.pdf new file: CHANGES.txt new file: LICENSE-dire-wolf.txt new file: LICENSE-other.txt new file: Makefile.linux new file: Makefile.win new file: Quick-Start-Guide-Windows.pdf new file: Raspberry-Pi-APRS.pdf new file: User-Guide.pdf new file: aclients.c new file: aprs_tt.c new file: aprs_tt.h new file: atest.c new file: audio.c new file: audio.h new file: audio_win.c new file: ax25_pad.c new file: ax25_pad.h new file: beacon.c new file: beacon.h new file: config.c new file: config.h new file: decode_aprs.c new file: decode_aprs.h new file: dedupe.c new file: dedupe.h new file: demod.c new file: demod.h new file: demod_9600.c new file: demod_9600.h new file: demod_afsk.c new file: demod_afsk.h new file: digipeater.c new file: digipeater.h new file: direwolf.c new file: direwolf.conf new file: direwolf.desktop new file: direwolf.h new file: dsp.c new file: dsp.h new file: dtmf.c new file: dtmf.h new file: dw-icon.ico new file: dw-icon.png new file: dw-icon.rc new file: dw-start.sh new file: dwgps.c new file: dwgps.h new file: encode_aprs.c new file: encode_aprs.h new file: fcs_calc.c new file: fcs_calc.h new file: fsk_demod_agc.h new file: fsk_demod_state.h new file: fsk_filters.h new file: fsk_gen_filter.h new file: gen_packets.c new file: gen_tone.c new file: gen_tone.h new file: hdlc_rec.c new file: hdlc_rec.h new file: hdlc_rec2.c new file: hdlc_rec2.h new file: hdlc_send.c new file: hdlc_send.h new file: igate.c new file: igate.h new file: kiss.c new file: kiss.h new file: kiss_frame.c new file: kiss_frame.h new file: kissnet.c new file: kissnet.h new file: latlong.c new file: latlong.h new file: ll2utm.c new file: misc/README-dire-wolf.txt new file: misc/strcasestr.c new file: misc/strsep.c new file: misc/strtok_r.c new file: morse.c new file: multi_modem.c new file: multi_modem.h new file: ptt.c new file: ptt.h new file: pttest.c new file: rdq.c new file: rdq.h new file: redecode.c new file: redecode.h new file: regex/COPYING new file: regex/INSTALL new file: regex/LICENSES new file: regex/NEWS new file: regex/README new file: regex/README-dire-wolf.txt new file: regex/re_comp.h new file: regex/regcomp.c new file: regex/regex.c new file: regex/regex.h new file: regex/regex_internal.c new file: regex/regex_internal.h new file: regex/regexec.c new file: rrbb.c new file: rrbb.h new file: server.c new file: server.h new file: symbols-new.txt new file: symbols.c new file: symbols.h new file: symbolsX.txt new file: textcolor.c new file: textcolor.h new file: tocalls.txt new file: tq.c new file: tq.h new file: tt_text.c new file: tt_text.h new file: tt_user.c new file: tt_user.h new file: tune.h new file: udp_test.c new file: utm/LatLong-UTMconversion.c new file: utm/LatLong-UTMconversion.h new file: utm/README.txt new file: utm/SwissGrid.cpp new file: utm/UTMConversions.cpp new file: utm/constants.h new file: utm2ll.c new file: version.h new file: xmit.c new file: xmit.h
2015-07-27 00:35:07 +00:00
//
// This file is part of Dire Wolf, an amateur radio packet TNC.
//
// Copyright (C) 2011,2013 John Langner, WB2OSZ
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 2 of the License, or
// (at your option) any later version.
//
// 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
//
/*------------------------------------------------------------------
*
* Module: kiss.c
*
* Purpose: Act as a virtual KISS TNC for use by other packet radio applications.
*
* Input:
*
* Outputs:
*
* Description: This provides a pseudo terminal for communication with a client application.
*
* It implements the KISS TNC protocol as described in:
* http://www.ka9q.net/papers/kiss.html
*
* Briefly, a frame is composed of
*
* * FEND (0xC0)
* * Contents - with special escape sequences so a 0xc0
* byte in the data is not taken as end of frame.
* as part of the data.
* * FEND
*
* The first byte of the frame contains:
*
* * port number in upper nybble.
* * command in lower nybble.
*
*
* Commands from application recognized:
*
* 0 Data Frame AX.25 frame in raw format.
*
* 1 TXDELAY See explanation in xmit.c.
*
* 2 Persistence " "
*
* 3 SlotTime " "
*
* 4 TXtail " "
* Spec says it is obsolete but Xastir
* sends it and we respect it.
*
* 5 FullDuplex Ignored. Always full duplex.
*
* 6 SetHardware TNC specific. Ignored.
*
* FF Return Exit KISS mode. Ignored.
*
*
* Messages sent to client application:
*
* 0 Data Frame Received AX.25 frame in raw format.
*
*
*
* Platform differences:
*
* We can use a pseudo terminal for Linux or Cygwin applications.
* However, Microsoft Windows doesn't seem to have similar functionality.
* Native Windows applications expect to see a device named COM1,
* COM2, COM3, or COM4. Some might offer more flexibility but others
* might be limited to these four choices.
*
* The documentation instucts the user to install the com0com
* <EFBFBD>Null-modem emulator<EFBFBD> from http://sourceforge.net/projects/com0com/
* and configure it for COM3 & COM4.
*
* By default Dire Wolf will use COM3 (/dev/ttyS2 or /dev/com3 - lower case!)
* and the client application will use COM4 (available as /dev/ttyS or
* /dev/com4 for Cygwin applications).
*
*
* This can get confusing.
*
* If __WIN32__ is defined,
* We use the Windows interface to the specfied serial port.
* This could be a real serial port or the nullmodem driver
* connected to another application.
*
* If __CYGWIN__ is defined,
* We connect to a serial port as in the previous case but
* use the Linux I/O interface.
* We also supply a pseudo terminal for any Cygwin applications
* such as Xastir so the null modem is not needed.
*
* For the Linux case,
* We supply a pseudo terminal for use by other applications.
*
*
* Reference: http://www.robbayer.com/files/serial-win.pdf
*
*---------------------------------------------------------------*/
#include <stdio.h>
#include <unistd.h>
#if __WIN32__
#include <stdlib.h>
#include <windows.h>
#else
#define __USE_XOPEN2KXSI 1
#define __USE_XOPEN 1
//#define __USE_POSIX 1
#include <stdlib.h>
#include <ctype.h>
#include <fcntl.h>
#include <termios.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#endif
#include <assert.h>
#include <string.h>
#include "direwolf.h"
#include "tq.h"
#include "ax25_pad.h"
#include "textcolor.h"
#include "kiss.h"
#include "kiss_frame.h"
#include "xmit.h"
#if __WIN32__
typedef HANDLE MYFDTYPE;
#define MYFDERROR INVALID_HANDLE_VALUE
#else
typedef int MYFDTYPE;
#define MYFDERROR (-1)
#endif
static kiss_frame_t kf; /* Accumulated KISS frame and state of decoder. */
/*
* These are for a Linux/Cygwin pseudo terminal.
*/
#if ! __WIN32__
static MYFDTYPE pt_master_fd = MYFDERROR; /* File descriptor for my end. */
static MYFDTYPE pt_slave_fd = MYFDERROR; /* File descriptor for pseudo terminal */
/* for use by application. */
/*
* Symlink to pseudo terminal name which changes.
*/
#define DEV_KISS_TNC "/tmp/kisstnc"
#endif
/*
* This is for native Windows applications and a virtual null modem.
*/
#if __CYGWIN__ || __WIN32__
static MYFDTYPE nullmodem_fd = MYFDERROR;
#endif
static void * kiss_listen_thread (void *arg);
#if DEBUG9
static FILE *log_fp;
#endif
static int kiss_debug = 0; /* Print information flowing from and to client. */
void kiss_serial_set_debug (int n)
{
kiss_debug = n;
}
/* In server.c. Should probably move to some misc. function file. */
void hex_dump (unsigned char *p, int len);
/*-------------------------------------------------------------------
*
* Name: kiss_init
*
* Purpose: Set up a pseudo terminal acting as a virtual KISS TNC.
*
*
* Inputs: mc->nullmodem - name of device for our end of nullmodem.
*
* Outputs:
*
* Description: (1) Create a pseudo terminal for the client to use.
* (2) Start a new thread to listen for commands from client app
* so the main application doesn't block while we wait.
*
*
*--------------------------------------------------------------------*/
static MYFDTYPE kiss_open_pt (void);
static MYFDTYPE kiss_open_nullmodem (char *device);
void kiss_init (struct misc_config_s *mc)
{
int e;
#if __WIN32__
HANDLE kiss_nullmodem_listen_th;
#else
pthread_t kiss_pterm_listen_tid;
pthread_t kiss_nullmodem_listen_tid;
#endif
memset (&kf, 0, sizeof(kf));
/*
* This reads messages from client.
*/
#if ! __WIN32__
/*
* Pseudo terminal for Cygwin and Linux versions.
*/
pt_master_fd = MYFDERROR;
if (mc->enable_kiss_pt) {
pt_master_fd = kiss_open_pt ();
if (pt_master_fd != MYFDERROR) {
e = pthread_create (&kiss_pterm_listen_tid, (pthread_attr_t*)NULL, kiss_listen_thread, (void*)(long)pt_master_fd);
if (e != 0) {
text_color_set(DW_COLOR_ERROR);
perror("Could not create kiss listening thread for Linux pseudo terminal");
}
}
}
else {
text_color_set(DW_COLOR_INFO);
dw_printf ("Use -p command line option to enable KISS pseudo terminal.\n");
}
#endif
#if __CYGWIN__ || __WIN32
/*
* Cygwin and native Windows versions have serial port connection.
*/
if (strlen(mc->nullmodem) > 0) {
#if ! __WIN32__
/* Translate Windows device name into Linux name. */
/* COM1 -> /dev/ttyS0, etc. */
if (strncasecmp(mc->nullmodem, "COM", 3) == 0) {
int n = atoi (mc->nullmodem + 3);
text_color_set(DW_COLOR_INFO);
dw_printf ("Converted nullmodem device '%s'", mc->nullmodem);
if (n < 1) n = 1;
sprintf (mc->nullmodem, "/dev/ttyS%d", n-1);
dw_printf (" to Linux equivalent '%s'\n", mc->nullmodem);
}
#endif
nullmodem_fd = kiss_open_nullmodem (mc->nullmodem);
if (nullmodem_fd != MYFDERROR) {
#if __WIN32__
kiss_nullmodem_listen_th = _beginthreadex (NULL, 0, kiss_listen_thread, (void*)(long)nullmodem_fd, 0, NULL);
if (kiss_nullmodem_listen_th == NULL) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("Could not create kiss nullmodem thread\n");
return;
}
#else
e = pthread_create (&kiss_nullmodem_listen_tid, NULL, kiss_listen_thread, (void*)(long)nullmodem_fd);
if (e != 0) {
text_color_set(DW_COLOR_ERROR);
perror("Could not create kiss listening thread for Windows virtual COM port.");
}
#endif
}
}
#endif
#if DEBUG
text_color_set (DW_COLOR_DEBUG);
#if ! __WIN32__
dw_printf ("end of kiss_init: pt_master_fd = %d\n", pt_master_fd);
#endif
#if __CYGWIN__ || __WIN32__
dw_printf ("end of kiss_init: nullmodem_fd = %d\n", nullmodem_fd);
#endif
#endif
}
/*
* Returns fd for master side of pseudo terminal or MYFDERROR for error.
*/
#if ! __WIN32__
static MYFDTYPE kiss_open_pt (void)
{
int fd;
char *slave_device;
struct termios ts;
int e;
//int flags;
#if DEBUG
text_color_set(DW_COLOR_DEBUG);
dw_printf ("kiss_open_pt ( )\n");
#endif
fd = posix_openpt(O_RDWR|O_NOCTTY);
if (fd == MYFDERROR
|| grantpt (fd) == MYFDERROR
|| unlockpt (fd) == MYFDERROR
|| (slave_device = ptsname (fd)) == NULL) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("ERROR - Could not create pseudo terminal for KISS TNC.\n");
return (MYFDERROR);
}
e = tcgetattr (fd, &ts);
if (e != 0) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("Can't get pseudo terminal attributes, err=%d\n", e);
perror ("pt tcgetattr");
}
cfmakeraw (&ts);
ts.c_cc[VMIN] = 1; /* wait for at least one character */
ts.c_cc[VTIME] = 0; /* no fancy timing. */
e = tcsetattr (fd, TCSANOW, &ts);
if (e != 0) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("Can't set pseudo terminal attributes, err=%d\n", e);
perror ("pt tcsetattr");
}
/*
* After running for a while on Linux, the write eventually
* blocks if no one is reading from the other side of
* the pseudo terminal. We get stuck on the kiss data
* write and reception stops.
*
* I tried using ioctl(,TIOCOUTQ,) to see how much was in
* the queue but that always returned zero. (Ubuntu)
*
* Let's try using non-blocking writes and see if we get
* the EWOULDBLOCK status instead of hanging.
*/
#if 0 // this is worse. all writes fail. errno = 0 bad file descriptor
flags = fcntl(fd, F_GETFL, 0);
e = fcntl (fd, F_SETFL, flags | O_NONBLOCK);
if (e != 0) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("Can't set pseudo terminal to nonblocking, fcntl returns %d, errno = %d\n", e, errno);
perror ("pt fcntl");
}
#endif
#if 0 // same
flags = 1;
e = ioctl (fd, FIONBIO, &flags);
if (e != 0) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("Can't set pseudo terminal to nonblocking, ioctl returns %d, errno = %d\n", e, errno);
perror ("pt ioctl");
}
#endif
text_color_set(DW_COLOR_INFO);
dw_printf("Virtual KISS TNC is available on %s\n", slave_device);
dw_printf("WARNING - Dire Wolf will hang eventually if nothing is reading from it.\n");
/*
* The device name is not the same every time.
* This is inconvenient for the application because it might
* be necessary to change the device name in the configuration.
* Create a symlink, /tmp/kisstnc, so the application configuration
* does not need to change when the pseudo terminal name changes.
*/
//TODO: remove symlink on exit.
unlink (DEV_KISS_TNC);
if (symlink (slave_device, DEV_KISS_TNC) == 0) {
dw_printf ("Created symlink %s -> %s\n", DEV_KISS_TNC, slave_device);
}
else {
text_color_set(DW_COLOR_ERROR);
dw_printf ("Failed to create symlink %s\n", DEV_KISS_TNC);
perror ("");
}
#if 1
// Sample code shows this. Why would we open it here?
// On Ubuntu, the slave side disappears after a few
// seconds if no one opens it.
pt_slave_fd = open(slave_device, O_RDWR|O_NOCTTY);
if (pt_slave_fd < 0)
return MYFDERROR;
#endif
return (fd);
}
#endif
/*
* Returns fd for our side of null modem or MYFDERROR for error.
*/
#if __CYGWIN__ || __WIN32__
static MYFDTYPE kiss_open_nullmodem (char *devicename)
{
#if __WIN32__
MYFDTYPE fd;
DCB dcb;
int ok;
#if DEBUG
text_color_set(DW_COLOR_DEBUG);
dw_printf ("kiss_open_nullmodem ( '%s' )\n", devicename);
#endif
#if DEBUG9
log_fp = fopen ("kiss-debug.txt", "w");
#endif
// Need to use FILE_FLAG_OVERLAPPED for full duplex operation.
// Without it, write blocks when waiting on read.
// Read http://support.microsoft.com/kb/156932
fd = CreateFile(devicename, GENERIC_READ | GENERIC_WRITE,
0, NULL, OPEN_EXISTING, FILE_FLAG_OVERLAPPED, NULL);
if (fd == MYFDERROR) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("ERROR - Could not connect to %s side of null modem for Windows KISS TNC.\n", devicename);
return (MYFDERROR);
}
/* Reference: http://msdn.microsoft.com/en-us/library/windows/desktop/aa363201(v=vs.85).aspx */
memset (&dcb, 0, sizeof(dcb));
dcb.DCBlength = sizeof(DCB);
ok = GetCommState (fd, &dcb);
if (! ok) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("kiss_open_nullmodem: GetCommState failed.\n");
}
/* http://msdn.microsoft.com/en-us/library/windows/desktop/aa363214(v=vs.85).aspx */
// dcb.BaudRate ? shouldn't matter
dcb.fBinary = 1;
dcb.fParity = 0;
dcb.fOutxCtsFlow = 0;
dcb.fOutxDsrFlow = 0;
dcb.fDtrControl = 0;
dcb.fDsrSensitivity = 0;
dcb.fOutX = 0;
dcb.fInX = 0;
dcb.fErrorChar = 0;
dcb.fNull = 0; /* Don't drop nul characters! */
dcb.fRtsControl = 0;
dcb.ByteSize = 8;
dcb.Parity = NOPARITY;
dcb.StopBits = ONESTOPBIT;
ok = SetCommState (fd, &dcb);
if (! ok) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("kiss_open_nullmodem: SetCommState failed.\n");
}
text_color_set(DW_COLOR_INFO);
dw_printf("Virtual KISS TNC is connected to %s side of null modem.\n", devicename);
#else
/* Cygwin version. */
int fd;
struct termios ts;
int e;
#if DEBUG
text_color_set(DW_COLOR_DEBUG);
dw_printf ("kiss_open_nullmodem ( '%s' )\n", devicename);
#endif
fd = open (devicename, O_RDWR);
if (fd == MYFDERROR) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("ERROR - Could not connect to %s side of null modem for Windows KISS TNC.\n", devicename);
return (MYFDERROR);
}
e = tcgetattr (fd, &ts);
if (e != 0) { perror ("nm tcgetattr"); }
cfmakeraw (&ts);
ts.c_cc[VMIN] = 1; /* wait for at least one character */
ts.c_cc[VTIME] = 0; /* no fancy timing. */
e = tcsetattr (fd, TCSANOW, &ts);
if (e != 0) { perror ("nm tcsetattr"); }
text_color_set(DW_COLOR_INFO);
dw_printf("Virtual KISS TNC is connected to %s side of null modem.\n", devicename);
#endif
return (fd);
}
#endif
/*-------------------------------------------------------------------
*
* Name: kiss_send_rec_packet
*
* Purpose: Send a received packet or text string to the client app.
*
* Inputs: chan - Channel number where packet was received.
* 0 = first, 1 = second if any.
*
* pp - Identifier for packet object.
*
* fbuf - Address of raw received frame buffer
* or a text string.
*
* flen - Length of raw received frame not including the FCS
* or -1 for a text string.
*
*
* Description: Send message to client.
* We really don't care if anyone is listening or not.
* I don't even know if we can find out.
*
*
*--------------------------------------------------------------------*/
void kiss_send_rec_packet (int chan, unsigned char *fbuf, int flen)
{
unsigned char kiss_buff[2 * AX25_MAX_PACKET_LEN];
int kiss_len;
int j;
int err;
#if ! __WIN32__
if (pt_master_fd == MYFDERROR) {
return;
}
#endif
#if __CYGWIN__ || __WIN32__
if (nullmodem_fd == MYFDERROR) {
return;
}
#endif
if (flen < 0) {
flen = strlen((char*)fbuf);
if (kiss_debug) {
kiss_debug_print (TO_CLIENT, "Fake command prompt", fbuf, flen);
}
strcpy ((char *)kiss_buff, (char *)fbuf);
kiss_len = strlen((char *)kiss_buff);
}
else {
kiss_len = 0;
kiss_buff[kiss_len++] = FEND;
kiss_buff[kiss_len++] = chan << 4;
for (j=0; j<flen; j++) {
if (fbuf[j] == FEND) {
kiss_buff[kiss_len++] = FESC;
kiss_buff[kiss_len++] = TFEND;
}
else if (fbuf[j] == FESC) {
kiss_buff[kiss_len++] = FESC;
kiss_buff[kiss_len++] = TFESC;
}
else {
kiss_buff[kiss_len++] = fbuf[j];
}
assert (kiss_len < sizeof (kiss_buff));
}
kiss_buff[kiss_len++] = FEND;
/* This has the escapes but not the surrounding FENDs. */
if (kiss_debug) {
kiss_debug_print (TO_CLIENT, NULL, kiss_buff+1, kiss_len-2);
}
}
#if ! __WIN32__
/* Pseudo terminal for Cygwin and Linux. */
err = write (pt_master_fd, kiss_buff, (size_t)kiss_len);
if (err == -1 && errno == EWOULDBLOCK) {
#if DEBUG
text_color_set (DW_COLOR_INFO);
dw_printf ("KISS SEND - discarding message because write would block.\n");
#endif
}
else if (err != kiss_len)
{
text_color_set(DW_COLOR_ERROR);
dw_printf ("\nError sending KISS message to client application on pseudo terminal. fd=%d, len=%d, write returned %d, errno = %d\n\n",
pt_master_fd, kiss_len, err, errno);
perror ("pt write");
}
#endif
#if __CYGWIN__ || __WIN32__
/*
* This write can block if nothing is connected to the other end.
* The solution is found in the com0com ReadMe file:
*
* Q. My application hangs during its startup when it sends anything to one paired
* COM port. The only way to unhang it is to start HyperTerminal, which is connected
* to the other paired COM port. I didn't have this problem with physical serial
* ports.
* A. Your application can hang because receive buffer overrun is disabled by
* default. You can fix the problem by enabling receive buffer overrun for the
* receiving port. Also, to prevent some flow control issues you need to enable
* baud rate emulation for the sending port. So, if your application use port CNCA0
* and other paired port is CNCB0, then:
*
* 1. Launch the Setup Command Prompt shortcut.
* 2. Enter the change commands, for example:
*
* command> change CNCB0 EmuOverrun=yes
* command> change CNCA0 EmuBR=yes
*/
#if __WIN32__
DWORD nwritten;
/* Without this, write blocks while we are waiting on a read. */
static OVERLAPPED ov_wr;
memset (&ov_wr, 0, sizeof(ov_wr));
if ( ! WriteFile (nullmodem_fd, kiss_buff, kiss_len, &nwritten, &ov_wr))
{
err = GetLastError();
if (err != ERROR_IO_PENDING)
{
text_color_set(DW_COLOR_ERROR);
dw_printf ("\nError sending KISS message to client application thru null modem. Error %d.\n\n", (int)GetLastError());
//CloseHandle (nullmodem_fd);
//nullmodem_fd = MYFDERROR;
}
}
else if (nwritten != flen)
{
text_color_set(DW_COLOR_ERROR);
dw_printf ("\nError sending KISS message to client application thru null modem. Only %d of %d written.\n\n", (int)nwritten, kiss_len);
//CloseHandle (nullmodem_fd);
//nullmodem_fd = MYFDERROR;
}
#if DEBUG
/* Could wait with GetOverlappedResult but we never */
/* have an issues in this direction. */
//text_color_set(DW_COLOR_DEBUG);
//dw_printf ("KISS SEND completed. wrote %d / %d\n", nwritten, kiss_len);
#endif
#else
err = write (nullmodem_fd, kiss_buf, (size_t)kiss_len);
if (err != len)
{
text_color_set(DW_COLOR_ERROR);
dw_printf ("\nError sending KISS message to client application thru null modem. err=%d\n\n", err);
//close (nullmodem_fd);
//nullmodem_fd = MYFDERROR;
}
#endif
#endif
} /* kiss_send_rec_packet */
/*-------------------------------------------------------------------
*
* Name: kiss_listen_thread
*
* Purpose: Wait for messages from an application.
*
* Inputs: arg - File descriptor for reading.
*
* Outputs: pt_slave_fd - File descriptor for communicating with client app.
*
* Description: Process messages from the client application.
*
*--------------------------------------------------------------------*/
//TODO: should pass fd by reference so it can be zapped.
//BUG: If we close it here, that fact doesn't get back
// to the main receiving thread.
/* Return one byte (value 0 - 255) or terminate thread on error. */
static int kiss_get (MYFDTYPE fd)
{
unsigned char ch;
#if __WIN32__ /* Native Windows version. */
DWORD n;
static OVERLAPPED ov_rd;
memset (&ov_rd, 0, sizeof(ov_rd));
ov_rd.hEvent = CreateEvent (NULL, TRUE, FALSE, NULL);
/* Overlapped I/O makes reading rather complicated. */
/* See: http://msdn.microsoft.com/en-us/library/ms810467.aspx */
/* It seems that the read completes OK with a count */
/* of 0 every time we send a message to the serial port. */
n = 0; /* Number of characters read. */
while (n == 0) {
if ( ! ReadFile (fd, &ch, 1, &n, &ov_rd))
{
int err1 = GetLastError();
if (err1 == ERROR_IO_PENDING)
{
/* Wait for completion. */
if (WaitForSingleObject (ov_rd.hEvent, INFINITE) == WAIT_OBJECT_0)
{
if ( ! GetOverlappedResult (fd, &ov_rd, &n, 1))
{
int err3 = GetLastError();
text_color_set(DW_COLOR_ERROR);
dw_printf ("\nKISS GetOverlappedResult error %d.\n\n", err3);
}
else
{
/* Success! n should be 1 */
}
}
}
else
{
text_color_set(DW_COLOR_ERROR);
dw_printf ("\nKISS ReadFile error %d. Closing connection.\n\n", err1);
//CloseHandle (fd);
//fd = MYFDERROR;
//pthread_exit (NULL);
}
}
} /* end while n==0 */
CloseHandle(ov_rd.hEvent);
if (n != 1) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("\nKISS failed to get one byte. n=%d.\n\n", (int)n);
#if DEBUG9
fprintf (log_fp, "n=%d\n", n);
#endif
}
#else /* Linux/Cygwin version */
int n;
n = read(fd, &ch, (size_t)1);
if (n != 1) {
//text_color_set(DW_COLOR_ERROR);
//dw_printf ("\nError receiving kiss message from client application. Closing connection %d.\n\n", fd);
close (fd);
fd = MYFDERROR;
pthread_exit (NULL);
}
#endif
#if DEBUGx
text_color_set(DW_COLOR_DEBUG);
dw_printf ("kiss_get(%d) returns 0x%02x\n", fd, ch);
#endif
#if DEBUG9
fprintf (log_fp, "%02x %c %c", ch,
isprint(ch) ? ch : '.' ,
(isupper(ch>>1) || isdigit(ch>>1) || (ch>>1) == ' ') ? (ch>>1) : '.');
if (ch == FEND) fprintf (log_fp, " FEND");
if (ch == FESC) fprintf (log_fp, " FESC");
if (ch == TFEND) fprintf (log_fp, " TFEND");
if (ch == TFESC) fprintf (log_fp, " TFESC");
if (ch == '\r') fprintf (log_fp, " CR");
if (ch == '\n') fprintf (log_fp, " LF");
fprintf (log_fp, "\n");
if (ch == FEND) fflush (log_fp);
#endif
return (ch);
}
static void * kiss_listen_thread (void *arg)
{
MYFDTYPE fd = (MYFDTYPE)(long)arg;
unsigned char ch;
#if DEBUG
text_color_set(DW_COLOR_DEBUG);
dw_printf ("kiss_listen_thread ( %d )\n", fd);
#endif
while (1) {
ch = kiss_get(fd);
if (kiss_frame (&kf, ch, kiss_debug, kiss_send_rec_packet)) {
kiss_process_msg (&kf, kiss_debug);
}
} /* while (1) */
return (NULL); /* Unreachable but avoids compiler warning. */
}
/* end kiss.c */