/**
* WinPR: Windows Portable Runtime
* Serial Communication API
*
* Copyright 2014 Hewlett-Packard Development Company, L.P.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#if defined __linux__ && !defined ANDROID
#include <assert.h>
#include <errno.h>
#include <termios.h>
#include <unistd.h>
#include <winpr/io.h>
#include <winpr/wlog.h>
#include <winpr/wtypes.h>
#include "comm.h"
BOOL _comm_set_permissive(HANDLE hDevice, BOOL permissive)
{
WINPR_COMM* pComm = (WINPR_COMM*)hDevice;
if (hDevice == INVALID_HANDLE_VALUE)
{
SetLastError(ERROR_INVALID_HANDLE);
return FALSE;
}
if (!pComm || pComm->Type != HANDLE_TYPE_COMM)
{
SetLastError(ERROR_INVALID_HANDLE);
return FALSE;
}
pComm->permissive = permissive;
return TRUE;
}
/* Computes VTIME in deciseconds from Ti in milliseconds */
static UCHAR _vtime(ULONG Ti)
{
/* FIXME: look for an equivalent math function otherwise let
* do the compiler do the optimization */
if (Ti == 0)
return 0;
else if (Ti < 100)
return 1;
else if (Ti > 25500)
return 255; /* 0xFF */
else
return Ti / 100;
}
/**
* ERRORS:
* ERROR_INVALID_HANDLE
* ERROR_NOT_SUPPORTED
* ERROR_INVALID_PARAMETER
* ERROR_TIMEOUT
* ERROR_IO_DEVICE
* ERROR_BAD_DEVICE
*/
BOOL CommReadFile(HANDLE hDevice, LPVOID lpBuffer, DWORD nNumberOfBytesToRead,
LPDWORD lpNumberOfBytesRead, LPOVERLAPPED lpOverlapped)
{
WINPR_COMM* pComm = (WINPR_COMM*)hDevice;
int biggestFd = -1;
fd_set read_set;
int nbFds;
COMMTIMEOUTS* pTimeouts;
UCHAR vmin = 0;
UCHAR vtime = 0;
ULONGLONG Tmax = 0;
struct timeval tmaxTimeout, *pTmaxTimeout;
struct termios currentTermios;
EnterCriticalSection(&pComm->ReadLock); /* KISSer by the function's beginning */
if (hDevice == INVALID_HANDLE_VALUE)
{
SetLastError(ERROR_INVALID_HANDLE);
goto return_false;
}
if (!pComm || pComm->Type != HANDLE_TYPE_COMM)
{
SetLastError(ERROR_INVALID_HANDLE);
goto return_false;
}
if (lpOverlapped != NULL)
{
SetLastError(ERROR_NOT_SUPPORTED);
goto return_false;
}
if (lpNumberOfBytesRead == NULL)
{
SetLastError(ERROR_INVALID_PARAMETER); /* since we doesn't suppport lpOverlapped != NULL */
goto return_false;
}
*lpNumberOfBytesRead = 0; /* will be ajusted if required ... */
if (nNumberOfBytesToRead <= 0) /* N */
{
goto return_true; /* FIXME: or FALSE? */
}
if (tcgetattr(pComm->fd, ¤tTermios) < 0)
{
SetLastError(ERROR_IO_DEVICE);
goto return_false;
}
if (currentTermios.c_lflag & ICANON)
{
CommLog_Print(WLOG_WARN, "Canonical mode not supported"); /* the timeout could not be set */
SetLastError(ERROR_NOT_SUPPORTED);
goto return_false;
}
/* http://msdn.microsoft.com/en-us/library/hh439614%28v=vs.85%29.aspx
* http://msdn.microsoft.com/en-us/library/windows/hardware/hh439614%28v=vs.85%29.aspx
*
* ReadIntervalTimeout | ReadTotalTimeoutMultiplier | ReadTotalTimeoutConstant | VMIN | VTIME |
* TMAX | 0 | 0 | 0 | N | 0 |
* INDEF | Blocks for N bytes available. 0< Ti <MAXULONG | 0 | 0 |
* N | Ti | INDEF | Blocks on first byte, then use Ti between bytes. MAXULONG | 0 | 0
* | 0 | 0 | 0 | Returns immediately with bytes available (don't block) MAXULONG |
* MAXULONG | 0< Tc <MAXULONG | N | 0 | Tc | Blocks on first byte
* during Tc or returns immediately whith bytes available MAXULONG | m |
* MAXULONG | | Invalid 0 | m | 0< Tc
* <MAXULONG | N | 0 | Tmax | Blocks on first byte during Tmax or returns
* immediately whith bytes available 0< Ti <MAXULONG | m | 0<
* Tc <MAXULONG | N | Ti | Tmax | Blocks on first byte, then use Ti between bytes.
* Tmax is used for the whole system call.
*/
/* NB: timeouts are in milliseconds, VTIME are in deciseconds and is an unsigned char */
/* FIXME: double check whether open(pComm->fd_read_event, O_NONBLOCK) doesn't conflict with
* above use cases */
pTimeouts = &(pComm->timeouts);
if ((pTimeouts->ReadIntervalTimeout == MAXULONG) &&
(pTimeouts->ReadTotalTimeoutConstant == MAXULONG))
{
CommLog_Print(
WLOG_WARN,
"ReadIntervalTimeout and ReadTotalTimeoutConstant cannot be both set to MAXULONG");
SetLastError(ERROR_INVALID_PARAMETER);
goto return_false;
}
/* VMIN */
if ((pTimeouts->ReadIntervalTimeout == MAXULONG) &&
(pTimeouts->ReadTotalTimeoutMultiplier == 0) && (pTimeouts->ReadTotalTimeoutConstant == 0))
{
vmin = 0;
}
else
{
/* N */
/* vmin = nNumberOfBytesToRead < 256 ? nNumberOfBytesToRead : 255;*/ /* 0xFF */
/* NB: we might wait endlessly with vmin=N, prefer to
* force vmin=1 and return with bytes
* available. FIXME: is a feature disarded here? */
vmin = 1;
}
/* VTIME */
if ((pTimeouts->ReadIntervalTimeout > 0) && (pTimeouts->ReadIntervalTimeout < MAXULONG))
{
/* Ti */
vtime = _vtime(pTimeouts->ReadIntervalTimeout);
}
/* TMAX */
pTmaxTimeout = &tmaxTimeout;
if ((pTimeouts->ReadIntervalTimeout == MAXULONG) &&
(pTimeouts->ReadTotalTimeoutMultiplier == MAXULONG))
{
/* Tc */
Tmax = pTimeouts->ReadTotalTimeoutConstant;
}
else
{
/* Tmax */
Tmax = nNumberOfBytesToRead * pTimeouts->ReadTotalTimeoutMultiplier +
pTimeouts->ReadTotalTimeoutConstant;
/* INDEFinitely */
if ((Tmax == 0) && (pTimeouts->ReadIntervalTimeout < MAXULONG) &&
(pTimeouts->ReadTotalTimeoutMultiplier == 0))
pTmaxTimeout = NULL;
}
if ((currentTermios.c_cc[VMIN] != vmin) || (currentTermios.c_cc[VTIME] != vtime))
{
currentTermios.c_cc[VMIN] = vmin;
currentTermios.c_cc[VTIME] = vtime;
if (tcsetattr(pComm->fd, TCSANOW, ¤tTermios) < 0)
{
CommLog_Print(WLOG_WARN,
"CommReadFile failure, could not apply new timeout values: VMIN=%" PRIu8
", VTIME=%" PRIu8 "",
vmin, vtime);
SetLastError(ERROR_IO_DEVICE);
goto return_false;
}
}
/* wait indefinitely if pTmaxTimeout is NULL */
if (pTmaxTimeout != NULL)
{
ZeroMemory(pTmaxTimeout, sizeof(struct timeval));
if (Tmax > 0) /* return immdiately if Tmax == 0 */
{
pTmaxTimeout->tv_sec = Tmax / 1000; /* s */
pTmaxTimeout->tv_usec = (Tmax % 1000) * 1000; /* us */
}
}
/* FIXME: had expected eventfd_write() to return EAGAIN when
* there is no eventfd_read() but this not the case. */
/* discard a possible and no more relevant event */
eventfd_read(pComm->fd_read_event, NULL);
biggestFd = pComm->fd_read;
if (pComm->fd_read_event > biggestFd)
biggestFd = pComm->fd_read_event;
FD_ZERO(&read_set);
assert(pComm->fd_read_event < FD_SETSIZE);
assert(pComm->fd_read < FD_SETSIZE);
FD_SET(pComm->fd_read_event, &read_set);
FD_SET(pComm->fd_read, &read_set);
nbFds = select(biggestFd + 1, &read_set, NULL, NULL, pTmaxTimeout);
if (nbFds < 0)
{
CommLog_Print(WLOG_WARN, "select() failure, errno=[%d] %s\n", errno, strerror(errno));
SetLastError(ERROR_IO_DEVICE);
goto return_false;
}
if (nbFds == 0)
{
/* timeout */
SetLastError(ERROR_TIMEOUT);
goto return_false;
}
/* read_set */
if (FD_ISSET(pComm->fd_read_event, &read_set))
{
eventfd_t event = 0;
if (eventfd_read(pComm->fd_read_event, &event) < 0)
{
if (errno == EAGAIN)
{
assert(FALSE); /* not quite sure this should ever happen */
/* keep on */
}
else
{
CommLog_Print(WLOG_WARN,
"unexpected error on reading fd_read_event, errno=[%d] %s\n", errno,
strerror(errno));
/* FIXME: goto return_false ? */
}
assert(errno == EAGAIN);
}
if (event == FREERDP_PURGE_RXABORT)
{
SetLastError(ERROR_CANCELLED);
goto return_false;
}
assert(event == FREERDP_PURGE_RXABORT); /* no other expected event so far */
}
if (FD_ISSET(pComm->fd_read, &read_set))
{
ssize_t nbRead = 0;
nbRead = read(pComm->fd_read, lpBuffer, nNumberOfBytesToRead);
if (nbRead < 0)
{
CommLog_Print(WLOG_WARN,
"CommReadFile failed, ReadIntervalTimeout=%" PRIu32
", ReadTotalTimeoutMultiplier=%" PRIu32
", ReadTotalTimeoutConstant=%" PRIu32 " VMIN=%u, VTIME=%u",
pTimeouts->ReadIntervalTimeout, pTimeouts->ReadTotalTimeoutMultiplier,
pTimeouts->ReadTotalTimeoutConstant, currentTermios.c_cc[VMIN],
currentTermios.c_cc[VTIME]);
CommLog_Print(WLOG_WARN,
"CommReadFile failed, nNumberOfBytesToRead=%" PRIu32 ", errno=[%d] %s",
nNumberOfBytesToRead, errno, strerror(errno));
if (errno == EAGAIN)
{
/* keep on */
goto return_true; /* expect a read-loop to be implemented on the server side */
}
else if (errno == EBADF)
{
SetLastError(ERROR_BAD_DEVICE); /* STATUS_INVALID_DEVICE_REQUEST */
goto return_false;
}
else
{
assert(FALSE);
SetLastError(ERROR_IO_DEVICE);
goto return_false;
}
}
if (nbRead == 0)
{
/* termios timeout */
SetLastError(ERROR_TIMEOUT);
goto return_false;
}
*lpNumberOfBytesRead = nbRead;
EnterCriticalSection(&pComm->EventsLock);
if (pComm->PendingEvents & SERIAL_EV_FREERDP_WAITING)
{
if (pComm->eventChar != '\0' && memchr(lpBuffer, pComm->eventChar, nbRead))
pComm->PendingEvents |= SERIAL_EV_RXCHAR;
}
LeaveCriticalSection(&pComm->EventsLock);
goto return_true;
}
assert(FALSE);
*lpNumberOfBytesRead = 0;
return_false:
LeaveCriticalSection(&pComm->ReadLock);
return FALSE;
return_true:
LeaveCriticalSection(&pComm->ReadLock);
return TRUE;
}
/**
* ERRORS:
* ERROR_INVALID_HANDLE
* ERROR_NOT_SUPPORTED
* ERROR_INVALID_PARAMETER
* ERROR_BAD_DEVICE
*/
BOOL CommWriteFile(HANDLE hDevice, LPCVOID lpBuffer, DWORD nNumberOfBytesToWrite,
LPDWORD lpNumberOfBytesWritten, LPOVERLAPPED lpOverlapped)
{
WINPR_COMM* pComm = (WINPR_COMM*)hDevice;
struct timeval tmaxTimeout, *pTmaxTimeout;
EnterCriticalSection(&pComm->WriteLock); /* KISSer by the function's beginning */
if (hDevice == INVALID_HANDLE_VALUE)
{
SetLastError(ERROR_INVALID_HANDLE);
goto return_false;
}
if (!pComm || pComm->Type != HANDLE_TYPE_COMM)
{
SetLastError(ERROR_INVALID_HANDLE);
goto return_false;
}
if (lpOverlapped != NULL)
{
SetLastError(ERROR_NOT_SUPPORTED);
goto return_false;
}
if (lpNumberOfBytesWritten == NULL)
{
SetLastError(ERROR_INVALID_PARAMETER); /* since we doesn't suppport lpOverlapped != NULL */
goto return_false;
}
*lpNumberOfBytesWritten = 0; /* will be ajusted if required ... */
if (nNumberOfBytesToWrite <= 0)
{
goto return_true; /* FIXME: or FALSE? */
}
/* FIXME: had expected eventfd_write() to return EAGAIN when
* there is no eventfd_read() but this not the case. */
/* discard a possible and no more relevant event */
eventfd_read(pComm->fd_write_event, NULL);
/* ms */
ULONGLONG Tmax = nNumberOfBytesToWrite * pComm->timeouts.WriteTotalTimeoutMultiplier +
pComm->timeouts.WriteTotalTimeoutConstant;
/* NB: select() may update the timeout argument to indicate
* how much time was left. Keep the timeout variable out of
* the while() */
pTmaxTimeout = &tmaxTimeout;
ZeroMemory(pTmaxTimeout, sizeof(struct timeval));
if (Tmax > 0)
{
pTmaxTimeout->tv_sec = Tmax / 1000; /* s */
pTmaxTimeout->tv_usec = (Tmax % 1000) * 1000; /* us */
}
else if ((pComm->timeouts.WriteTotalTimeoutMultiplier == 0) &&
(pComm->timeouts.WriteTotalTimeoutConstant == 0))
{
pTmaxTimeout = NULL;
}
/* else return immdiately */
while (*lpNumberOfBytesWritten < nNumberOfBytesToWrite)
{
int biggestFd = -1;
fd_set event_set, write_set;
int nbFds;
biggestFd = pComm->fd_write;
if (pComm->fd_write_event > biggestFd)
biggestFd = pComm->fd_write_event;
FD_ZERO(&event_set);
FD_ZERO(&write_set);
assert(pComm->fd_write_event < FD_SETSIZE);
assert(pComm->fd_write < FD_SETSIZE);
FD_SET(pComm->fd_write_event, &event_set);
FD_SET(pComm->fd_write, &write_set);
nbFds = select(biggestFd + 1, &event_set, &write_set, NULL, pTmaxTimeout);
if (nbFds < 0)
{
CommLog_Print(WLOG_WARN, "select() failure, errno=[%d] %s\n", errno, strerror(errno));
SetLastError(ERROR_IO_DEVICE);
goto return_false;
}
if (nbFds == 0)
{
/* timeout */
SetLastError(ERROR_TIMEOUT);
goto return_false;
}
/* event_set */
if (FD_ISSET(pComm->fd_write_event, &event_set))
{
eventfd_t event = 0;
if (eventfd_read(pComm->fd_write_event, &event) < 0)
{
if (errno == EAGAIN)
{
assert(FALSE); /* not quite sure this should ever happen */
/* keep on */
}
else
{
CommLog_Print(WLOG_WARN,
"unexpected error on reading fd_write_event, errno=[%d] %s\n",
errno, strerror(errno));
/* FIXME: goto return_false ? */
}
assert(errno == EAGAIN);
}
if (event == FREERDP_PURGE_TXABORT)
{
SetLastError(ERROR_CANCELLED);
goto return_false;
}
assert(event == FREERDP_PURGE_TXABORT); /* no other expected event so far */
}
/* write_set */
if (FD_ISSET(pComm->fd_write, &write_set))
{
ssize_t nbWritten;
nbWritten = write(pComm->fd_write, ((BYTE*)lpBuffer) + (*lpNumberOfBytesWritten),
nNumberOfBytesToWrite - (*lpNumberOfBytesWritten));
if (nbWritten < 0)
{
CommLog_Print(WLOG_WARN,
"CommWriteFile failed after %" PRIu32
" bytes written, errno=[%d] %s\n",
*lpNumberOfBytesWritten, errno, strerror(errno));
if (errno == EAGAIN)
{
/* keep on */
continue;
}
else if (errno == EBADF)
{
SetLastError(ERROR_BAD_DEVICE); /* STATUS_INVALID_DEVICE_REQUEST */
goto return_false;
}
else
{
assert(FALSE);
SetLastError(ERROR_IO_DEVICE);
goto return_false;
}
}
*lpNumberOfBytesWritten += nbWritten;
}
} /* while */
/* FIXME: this call to tcdrain() doesn't look correct and
* might hide a bug but was required while testing a serial
* printer. Its driver was expecting the modem line status
* SERIAL_MSR_DSR true after the sending which was never
* happenning otherwise. A purge was also done before each
* Write operation. The serial port was opened with:
* DesiredAccess=0x0012019F. The printer worked fine with
* mstsc. */
tcdrain(pComm->fd_write);
return_true:
LeaveCriticalSection(&pComm->WriteLock);
return TRUE;
return_false:
LeaveCriticalSection(&pComm->WriteLock);
return FALSE;
}
#endif /* __linux__ */