pe.old/WINDOWS/WINSER.C
/*
* Serial back end (Windows-specific).
*/
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include "putty.h"
#define SERIAL_MAX_BACKLOG 4096
typedef struct serial_backend_data {
HANDLE port;
struct handle *out, *in;
void *frontend;
int bufsize;
long clearbreak_time;
int break_in_progress;
} *Serial;
static void serial_terminate(Serial serial)
{
if (serial->out) {
handle_free(serial->out);
serial->out = NULL;
}
if (serial->in) {
handle_free(serial->in);
serial->in = NULL;
}
if (serial->port != INVALID_HANDLE_VALUE) {
if (serial->break_in_progress)
ClearCommBreak(serial->port);
CloseHandle(serial->port);
serial->port = INVALID_HANDLE_VALUE;
}
}
static int serial_gotdata(struct handle *h, void *data, int len)
{
Serial serial = (Serial)handle_get_privdata(h);
if (len <= 0) {
const char *error_msg;
/*
* Currently, len==0 should never happen because we're
* ignoring EOFs. However, it seems not totally impossible
* that this same back end might be usable to talk to named
* pipes or some other non-serial device, in which case EOF
* may become meaningful here.
*/
if (len == 0)
error_msg = "End of file reading from serial device";
else
error_msg = "Error reading from serial device";
serial_terminate(serial);
notify_remote_exit(serial->frontend);
logevent(serial->frontend, error_msg);
connection_fatal(serial->frontend, "%s", error_msg);
return 0; /* placate optimiser */
} else {
return from_backend(serial->frontend, 0, data, len);
}
}
static void serial_sentdata(struct handle *h, int new_backlog)
{
Serial serial = (Serial)handle_get_privdata(h);
if (new_backlog < 0) {
const char *error_msg = "Error writing to serial device";
serial_terminate(serial);
notify_remote_exit(serial->frontend);
logevent(serial->frontend, error_msg);
connection_fatal(serial->frontend, "%s", error_msg);
} else {
serial->bufsize = new_backlog;
}
}
static const char *serial_configure(Serial serial, HANDLE serport, Config *cfg)
{
DCB dcb;
COMMTIMEOUTS timeouts;
/*
* Set up the serial port parameters. If we can't even
* GetCommState, we ignore the problem on the grounds that the
* user might have pointed us at some other type of two-way
* device instead of a serial port.
*/
if (GetCommState(serport, &dcb)) {
char *msg;
const char *str;
/*
* Boilerplate.
*/
dcb.fBinary = TRUE;
dcb.fDtrControl = DTR_CONTROL_ENABLE;
dcb.fDsrSensitivity = FALSE;
dcb.fTXContinueOnXoff = FALSE;
dcb.fOutX = FALSE;
dcb.fInX = FALSE;
dcb.fErrorChar = FALSE;
dcb.fNull = FALSE;
dcb.fRtsControl = RTS_CONTROL_ENABLE;
dcb.fAbortOnError = FALSE;
dcb.fOutxCtsFlow = FALSE;
dcb.fOutxDsrFlow = FALSE;
/*
* Configurable parameters.
*/
dcb.BaudRate = cfg->serspeed;
msg = dupprintf("Configuring baud rate %d", cfg->serspeed);
logevent(serial->frontend, msg);
sfree(msg);
dcb.ByteSize = cfg->serdatabits;
msg = dupprintf("Configuring %d data bits", cfg->serdatabits);
logevent(serial->frontend, msg);
sfree(msg);
switch (cfg->serstopbits) {
case 2: dcb.StopBits = ONESTOPBIT; str = "1"; break;
case 3: dcb.StopBits = ONE5STOPBITS; str = "1.5"; break;
case 4: dcb.StopBits = TWOSTOPBITS; str = "2"; break;
default: return "Invalid number of stop bits (need 1, 1.5 or 2)";
}
msg = dupprintf("Configuring %s data bits", str);
logevent(serial->frontend, msg);
sfree(msg);
switch (cfg->serparity) {
case SER_PAR_NONE: dcb.Parity = NOPARITY; str = "no"; break;
case SER_PAR_ODD: dcb.Parity = ODDPARITY; str = "odd"; break;
case SER_PAR_EVEN: dcb.Parity = EVENPARITY; str = "even"; break;
case SER_PAR_MARK: dcb.Parity = MARKPARITY; str = "mark"; break;
case SER_PAR_SPACE: dcb.Parity = SPACEPARITY; str = "space"; break;
}
msg = dupprintf("Configuring %s parity", str);
logevent(serial->frontend, msg);
sfree(msg);
switch (cfg->serflow) {
case SER_FLOW_NONE:
str = "no";
break;
case SER_FLOW_XONXOFF:
dcb.fOutX = dcb.fInX = TRUE;
str = "XON/XOFF";
break;
case SER_FLOW_RTSCTS:
dcb.fRtsControl = RTS_CONTROL_HANDSHAKE;
dcb.fOutxCtsFlow = TRUE;
str = "RTS/CTS";
break;
case SER_FLOW_DSRDTR:
dcb.fDtrControl = DTR_CONTROL_HANDSHAKE;
dcb.fOutxDsrFlow = TRUE;
str = "DSR/DTR";
break;
}
msg = dupprintf("Configuring %s flow control", str);
logevent(serial->frontend, msg);
sfree(msg);
if (!SetCommState(serport, &dcb))
return "Unable to configure serial port";
timeouts.ReadIntervalTimeout = 1;
timeouts.ReadTotalTimeoutMultiplier = 0;
timeouts.ReadTotalTimeoutConstant = 0;
timeouts.WriteTotalTimeoutMultiplier = 0;
timeouts.WriteTotalTimeoutConstant = 0;
if (!SetCommTimeouts(serport, &timeouts))
return "Unable to configure serial timeouts";
}
return NULL;
}
/*
* Called to set up the serial connection.
*
* Returns an error message, or NULL on success.
*
* Also places the canonical host name into `realhost'. It must be
* freed by the caller.
*/
static const char *serial_init(void *frontend_handle, void **backend_handle,
Config *cfg,
char *host, int port, char **realhost, int nodelay,
int keepalive)
{
Serial serial;
HANDLE serport;
const char *err;
serial = snew(struct serial_backend_data);
serial->port = INVALID_HANDLE_VALUE;
serial->out = serial->in = NULL;
serial->bufsize = 0;
serial->break_in_progress = FALSE;
*backend_handle = serial;
serial->frontend = frontend_handle;
{
char *msg = dupprintf("Opening serial device %s", cfg->serline);
logevent(serial->frontend, msg);
}
{
/*
* Munge the string supplied by the user into a Windows filename.
*
* Windows supports opening a few "legacy" devices (including
* COM1-9) by specifying their names verbatim as a filename to
* open. (Thus, no files can ever have these names. See
* <http://msdn2.microsoft.com/en-us/library/aa365247.aspx>
* ("Naming a File") for the complete list of reserved names.)
*
* However, this doesn't let you get at devices COM10 and above.
* For that, you need to specify a filename like "\\.\COM10".
* This is also necessary for special serial and serial-like
* devices such as \\.\WCEUSBSH001. It also works for the "legacy"
* names, so you can do \\.\COM1 (verified as far back as Win95).
* See <http://msdn2.microsoft.com/en-us/library/aa363858.aspx>
* (CreateFile() docs).
*
* So, we believe that prepending "\\.\" should always be the
* Right Thing. However, just in case someone finds something to
* talk to that doesn't exist under there, if the serial line
* contains a backslash, we use it verbatim. (This also lets
* existing configurations using \\.\ continue working.)
*/
char *serfilename =
dupprintf("%s%s",
strchr(cfg->serline, '\\') ? "" : "\\\\.\\",
cfg->serline);
serport = CreateFile(serfilename, GENERIC_READ | GENERIC_WRITE, 0, NULL,
OPEN_EXISTING, FILE_FLAG_OVERLAPPED, NULL);
sfree(serfilename);
}
if (serport == INVALID_HANDLE_VALUE)
return "Unable to open serial port";
err = serial_configure(serial, serport, cfg);
if (err)
return err;
serial->port = serport;
serial->out = handle_output_new(serport, serial_sentdata, serial,
HANDLE_FLAG_OVERLAPPED);
serial->in = handle_input_new(serport, serial_gotdata, serial,
HANDLE_FLAG_OVERLAPPED |
HANDLE_FLAG_IGNOREEOF |
HANDLE_FLAG_UNITBUFFER);
*realhost = dupstr(cfg->serline);
/*
* Specials are always available.
*/
update_specials_menu(serial->frontend);
return NULL;
}
static void serial_free(void *handle)
{
Serial serial = (Serial) handle;
serial_terminate(serial);
expire_timer_context(serial);
sfree(serial);
}
static void serial_reconfig(void *handle, Config *cfg)
{
Serial serial = (Serial) handle;
const char *err;
err = serial_configure(serial, serial->port, cfg);
/*
* FIXME: what should we do if err returns something?
*/
}
/*
* Called to send data down the serial connection.
*/
static int serial_send(void *handle, char *buf, int len)
{
Serial serial = (Serial) handle;
if (serial->out == NULL)
return 0;
serial->bufsize = handle_write(serial->out, buf, len);
return serial->bufsize;
}
/*
* Called to query the current sendability status.
*/
static int serial_sendbuffer(void *handle)
{
Serial serial = (Serial) handle;
return serial->bufsize;
}
/*
* Called to set the size of the window
*/
static void serial_size(void *handle, int width, int height)
{
/* Do nothing! */
return;
}
static void serbreak_timer(void *ctx, long now)
{
Serial serial = (Serial)ctx;
if (now >= serial->clearbreak_time && serial->port) {
ClearCommBreak(serial->port);
serial->break_in_progress = FALSE;
logevent(serial->frontend, "Finished serial break");
}
}
/*
* Send serial special codes.
*/
static void serial_special(void *handle, Telnet_Special code)
{
Serial serial = (Serial) handle;
if (serial->port && code == TS_BRK) {
logevent(serial->frontend, "Starting serial break at user request");
SetCommBreak(serial->port);
/*
* To send a serial break on Windows, we call SetCommBreak
* to begin the break, then wait a bit, and then call
* ClearCommBreak to finish it. Hence, I must use timing.c
* to arrange a callback when it's time to do the latter.
*
* SUS says that a default break length must be between 1/4
* and 1/2 second. FreeBSD apparently goes with 2/5 second,
* and so will I.
*/
serial->clearbreak_time =
schedule_timer(TICKSPERSEC * 2 / 5, serbreak_timer, serial);
serial->break_in_progress = TRUE;
}
return;
}
/*
* Return a list of the special codes that make sense in this
* protocol.
*/
static const struct telnet_special *serial_get_specials(void *handle)
{
static const struct telnet_special specials[] = {
{"Break", TS_BRK},
{NULL, TS_EXITMENU}
};
return specials;
}
static int serial_connected(void *handle)
{
return 1; /* always connected */
}
static int serial_sendok(void *handle)
{
return 1;
}
static void serial_unthrottle(void *handle, int backlog)
{
Serial serial = (Serial) handle;
if (serial->in)
handle_unthrottle(serial->in, backlog);
}
static int serial_ldisc(void *handle, int option)
{
/*
* Local editing and local echo are off by default.
*/
return 0;
}
static void serial_provide_ldisc(void *handle, void *ldisc)
{
/* This is a stub. */
}
static void serial_provide_logctx(void *handle, void *logctx)
{
/* This is a stub. */
}
static int serial_exitcode(void *handle)
{
Serial serial = (Serial) handle;
if (serial->port != INVALID_HANDLE_VALUE)
return -1; /* still connected */
else
/* Exit codes are a meaningless concept with serial ports */
return INT_MAX;
}
/*
* cfg_info for Serial does nothing at all.
*/
static int serial_cfg_info(void *handle)
{
return 0;
}
Backend serial_backend = {
serial_init,
serial_free,
serial_reconfig,
serial_send,
serial_sendbuffer,
serial_size,
serial_special,
serial_get_specials,
serial_connected,
serial_exitcode,
serial_sendok,
serial_ldisc,
serial_provide_ldisc,
serial_provide_logctx,
serial_unthrottle,
serial_cfg_info,
"serial",
PROT_SERIAL,
0
};