tclWinSerial.c
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上传日期:2015-12-11
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- /*
- * tclWinSerial.c --
- *
- * This file implements the Windows-specific serial port functions,
- * and the "serial" channel driver.
- *
- * Copyright (c) 1999 by Scriptics Corp.
- *
- * See the file "license.terms" for information on usage and redistribution
- * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
- *
- * Serial functionality implemented by Rolf.Schroedter@dlr.de
- *
- * RCS: @(#) $Id: tclWinSerial.c,v 1.25.2.4 2008/01/14 00:11:22 hobbs Exp $
- */
- #include "tclWinInt.h"
- #include <fcntl.h>
- #include <io.h>
- #include <sys/stat.h>
- /*
- * The following variable is used to tell whether this module has been
- * initialized.
- */
- static int initialized = 0;
- /*
- * The serialMutex locks around access to the initialized variable, and it is
- * used to protect background threads from being terminated while they are
- * using APIs that hold locks.
- */
- TCL_DECLARE_MUTEX(serialMutex)
- /*
- * Bit masks used in the flags field of the SerialInfo structure below.
- */
- #define SERIAL_PENDING (1<<0) /* Message is pending in the queue. */
- #define SERIAL_ASYNC (1<<1) /* Channel is non-blocking. */
- /*
- * Bit masks used in the sharedFlags field of the SerialInfo structure below.
- */
- #define SERIAL_EOF (1<<2) /* Serial has reached EOF. */
- #define SERIAL_ERROR (1<<4)
- /*
- * Default time to block between checking status on the serial port.
- */
- #define SERIAL_DEFAULT_BLOCKTIME 10 /* 10 msec */
- /*
- * Define Win32 read/write error masks returned by ClearCommError()
- */
- #define SERIAL_READ_ERRORS ( CE_RXOVER | CE_OVERRUN | CE_RXPARITY
- | CE_FRAME | CE_BREAK )
- #define SERIAL_WRITE_ERRORS ( CE_TXFULL | CE_PTO )
- /*
- * This structure describes per-instance data for a serial based channel.
- */
- typedef struct SerialInfo {
- HANDLE handle;
- struct SerialInfo *nextPtr; /* Pointer to next registered serial. */
- Tcl_Channel channel; /* Pointer to channel structure. */
- int validMask; /* OR'ed combination of TCL_READABLE,
- * TCL_WRITABLE, or TCL_EXCEPTION: indicates
- * which operations are valid on the file. */
- int watchMask; /* OR'ed combination of TCL_READABLE,
- * TCL_WRITABLE, or TCL_EXCEPTION: indicates
- * which events should be reported. */
- int flags; /* State flags, see above for a list. */
- int readable; /* flag that the channel is readable */
- int writable; /* flag that the channel is writable */
- int blockTime; /* max. blocktime in msec */
- unsigned int lastEventTime; /* Time in milliseconds since last readable event */
- /* Next readable event only after blockTime */
- DWORD error; /* pending error code returned by
- * ClearCommError() */
- DWORD lastError; /* last error code, can be fetched with
- * fconfigure chan -lasterror */
- DWORD sysBufRead; /* Win32 system buffer size for read ops,
- * default=4096 */
- DWORD sysBufWrite; /* Win32 system buffer size for write ops,
- * default=4096 */
- Tcl_ThreadId threadId; /* Thread to which events should be reported.
- * This value is used by the reader/writer
- * threads. */
- OVERLAPPED osRead; /* OVERLAPPED structure for read operations */
- OVERLAPPED osWrite; /* OVERLAPPED structure for write operations */
- HANDLE writeThread; /* Handle to writer thread. */
- CRITICAL_SECTION csWrite; /* Writer thread synchronisation */
- HANDLE evWritable; /* Manual-reset event to signal when the
- * writer thread has finished waiting for
- * the current buffer to be written. */
- HANDLE evStartWriter; /* Auto-reset event used by the main thread to
- * signal when the writer thread should attempt
- * to write to the serial. */
- HANDLE evStopWriter; /* Auto-reset event used by the main thread to
- * signal when the writer thread should close.
- */
- DWORD writeError; /* An error caused by the last background
- * write. Set to 0 if no error has been
- * detected. This word is shared with the
- * writer thread so access must be
- * synchronized with the evWritable object.
- */
- char *writeBuf; /* Current background output buffer.
- * Access is synchronized with the evWritable
- * object. */
- int writeBufLen; /* Size of write buffer. Access is
- * synchronized with the evWritable
- * object. */
- int toWrite; /* Current amount to be written. Access is
- * synchronized with the evWritable object. */
- int writeQueue; /* Number of bytes pending in output queue.
- * Offset to DCB.cbInQue.
- * Used to query [fconfigure -queue] */
- } SerialInfo;
- typedef struct ThreadSpecificData {
- /*
- * The following pointer refers to the head of the list of serials
- * that are being watched for file events.
- */
- SerialInfo *firstSerialPtr;
- } ThreadSpecificData;
- static Tcl_ThreadDataKey dataKey;
- /*
- * The following structure is what is added to the Tcl event queue when
- * serial events are generated.
- */
- typedef struct SerialEvent {
- Tcl_Event header; /* Information that is standard for
- * all events. */
- SerialInfo *infoPtr; /* Pointer to serial info structure. Note
- * that we still have to verify that the
- * serial exists before dereferencing this
- * pointer. */
- } SerialEvent;
- /*
- * We don't use timeouts.
- */
- static COMMTIMEOUTS no_timeout = {
- 0, /* ReadIntervalTimeout */
- 0, /* ReadTotalTimeoutMultiplier */
- 0, /* ReadTotalTimeoutConstant */
- 0, /* WriteTotalTimeoutMultiplier */
- 0, /* WriteTotalTimeoutConstant */
- };
- /*
- * Declarations for functions used only in this file.
- */
- static int SerialBlockProc(ClientData instanceData, int mode);
- static void SerialCheckProc(ClientData clientData, int flags);
- static int SerialCloseProc(ClientData instanceData,
- Tcl_Interp *interp);
- static int SerialEventProc(Tcl_Event *evPtr, int flags);
- static void SerialExitHandler(ClientData clientData);
- static int SerialGetHandleProc(ClientData instanceData,
- int direction, ClientData *handlePtr);
- static ThreadSpecificData *SerialInit(void);
- static int SerialInputProc(ClientData instanceData, char *buf,
- int toRead, int *errorCode);
- static int SerialOutputProc(ClientData instanceData, CONST char *buf,
- int toWrite, int *errorCode);
- static void SerialSetupProc(ClientData clientData, int flags);
- static void SerialWatchProc(ClientData instanceData, int mask);
- static void ProcExitHandler(ClientData clientData);
- static int SerialGetOptionProc _ANSI_ARGS_((ClientData instanceData,
- Tcl_Interp *interp, CONST char *optionName,
- Tcl_DString *dsPtr));
- static int SerialSetOptionProc _ANSI_ARGS_((ClientData instanceData,
- Tcl_Interp *interp, CONST char *optionName,
- CONST char *value));
- static DWORD WINAPI SerialWriterThread(LPVOID arg);
- static void SerialThreadActionProc _ANSI_ARGS_ ((
- ClientData instanceData, int action));
- /*
- * This structure describes the channel type structure for command serial
- * based IO.
- */
- static Tcl_ChannelType serialChannelType = {
- "serial", /* Type name. */
- TCL_CHANNEL_VERSION_4, /* v4 channel */
- SerialCloseProc, /* Close proc. */
- SerialInputProc, /* Input proc. */
- SerialOutputProc, /* Output proc. */
- NULL, /* Seek proc. */
- SerialSetOptionProc, /* Set option proc. */
- SerialGetOptionProc, /* Get option proc. */
- SerialWatchProc, /* Set up notifier to watch the channel. */
- SerialGetHandleProc, /* Get an OS handle from channel. */
- NULL, /* close2proc. */
- SerialBlockProc, /* Set blocking or non-blocking mode.*/
- NULL, /* flush proc. */
- NULL, /* handler proc. */
- NULL, /* wide seek proc */
- SerialThreadActionProc, /* thread action proc */
- };
- /*
- *----------------------------------------------------------------------
- *
- * SerialInit --
- *
- * This function initializes the static variables for this file.
- *
- * Results:
- * None.
- *
- * Side effects:
- * Creates a new event source.
- *
- *----------------------------------------------------------------------
- */
- static ThreadSpecificData *
- SerialInit()
- {
- ThreadSpecificData *tsdPtr;
- /*
- * Check the initialized flag first, then check it again in the mutex.
- * This is a speed enhancement.
- */
- if (!initialized) {
- Tcl_MutexLock(&serialMutex);
- if (!initialized) {
- initialized = 1;
- Tcl_CreateExitHandler(ProcExitHandler, NULL);
- }
- Tcl_MutexUnlock(&serialMutex);
- }
- tsdPtr = (ThreadSpecificData *)TclThreadDataKeyGet(&dataKey);
- if (tsdPtr == NULL) {
- tsdPtr = TCL_TSD_INIT(&dataKey);
- tsdPtr->firstSerialPtr = NULL;
- Tcl_CreateEventSource(SerialSetupProc, SerialCheckProc, NULL);
- Tcl_CreateThreadExitHandler(SerialExitHandler, NULL);
- }
- return tsdPtr;
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialExitHandler --
- *
- * This function is called to cleanup the serial module before
- * Tcl is unloaded.
- *
- * Results:
- * None.
- *
- * Side effects:
- * Removes the serial event source.
- *
- *----------------------------------------------------------------------
- */
- static void
- SerialExitHandler(
- ClientData clientData) /* Old window proc */
- {
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
- SerialInfo *infoPtr;
- /*
- * Clear all eventually pending output.
- * Otherwise Tcl's exit could totally block,
- * because it performs a blocking flush on all open channels.
- * Note that serial write operations may be blocked due to handshake.
- */
- for (infoPtr = tsdPtr->firstSerialPtr; infoPtr != NULL;
- infoPtr = infoPtr->nextPtr) {
- PurgeComm(infoPtr->handle, PURGE_TXABORT | PURGE_RXABORT | PURGE_TXCLEAR
- | PURGE_RXCLEAR);
- }
- Tcl_DeleteEventSource(SerialSetupProc, SerialCheckProc, NULL);
- }
- /*
- *----------------------------------------------------------------------
- *
- * ProcExitHandler --
- *
- * This function is called to cleanup the process list before
- * Tcl is unloaded.
- *
- * Results:
- * None.
- *
- * Side effects:
- * Resets the process list.
- *
- *----------------------------------------------------------------------
- */
- static void
- ProcExitHandler(
- ClientData clientData) /* Old window proc */
- {
- Tcl_MutexLock(&serialMutex);
- initialized = 0;
- Tcl_MutexUnlock(&serialMutex);
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialBlockTime --
- *
- * Wrapper to set Tcl's block time in msec
- *
- * Results:
- * None.
- *----------------------------------------------------------------------
- */
- static void
- SerialBlockTime(
- int msec) /* milli-seconds */
- {
- Tcl_Time blockTime;
- blockTime.sec = msec / 1000;
- blockTime.usec = (msec % 1000) * 1000;
- Tcl_SetMaxBlockTime(&blockTime);
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialGetMilliseconds --
- *
- * Get current time in milliseconds,
- * Don't care about integer overruns
- *
- * Results:
- * None.
- *----------------------------------------------------------------------
- */
- static unsigned int
- SerialGetMilliseconds(
- void)
- {
- Tcl_Time time;
- TclpGetTime(&time);
- return (time.sec * 1000 + time.usec / 1000);
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialSetupProc --
- *
- * This procedure is invoked before Tcl_DoOneEvent blocks waiting
- * for an event.
- *
- * Results:
- * None.
- *
- * Side effects:
- * Adjusts the block time if needed.
- *
- *----------------------------------------------------------------------
- */
- void
- SerialSetupProc(
- ClientData data, /* Not used. */
- int flags) /* Event flags as passed to Tcl_DoOneEvent. */
- {
- SerialInfo *infoPtr;
- int block = 1;
- int msec = INT_MAX; /* min. found block time */
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
- if (!(flags & TCL_FILE_EVENTS)) {
- return;
- }
- /*
- * Look to see if any events handlers installed. If they are, do not block.
- */
- for (infoPtr = tsdPtr->firstSerialPtr; infoPtr != NULL;
- infoPtr = infoPtr->nextPtr) {
- if (infoPtr->watchMask & TCL_WRITABLE) {
- if (WaitForSingleObject(infoPtr->evWritable, 0) != WAIT_TIMEOUT) {
- block = 0;
- msec = min( msec, infoPtr->blockTime );
- }
- }
- if( infoPtr->watchMask & TCL_READABLE ) {
- block = 0;
- msec = min( msec, infoPtr->blockTime );
- }
- }
- if (!block) {
- SerialBlockTime(msec);
- }
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialCheckProc --
- *
- * This procedure is called by Tcl_DoOneEvent to check the serial
- * event source for events.
- *
- * Results:
- * None.
- *
- * Side effects:
- * May queue an event.
- *
- *----------------------------------------------------------------------
- */
- static void
- SerialCheckProc(
- ClientData data, /* Not used. */
- int flags) /* Event flags as passed to Tcl_DoOneEvent. */
- {
- SerialInfo *infoPtr;
- SerialEvent *evPtr;
- int needEvent;
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
- COMSTAT cStat;
- unsigned int time;
- if (!(flags & TCL_FILE_EVENTS)) {
- return;
- }
- /*
- * Queue events for any ready serials that don't already have events
- * queued.
- */
- for (infoPtr = tsdPtr->firstSerialPtr; infoPtr != NULL;
- infoPtr = infoPtr->nextPtr) {
- if (infoPtr->flags & SERIAL_PENDING) {
- continue;
- }
- needEvent = 0;
- /*
- * If WRITABLE watch mask is set
- * look for infoPtr->evWritable object
- */
- if (infoPtr->watchMask & TCL_WRITABLE) {
- if (WaitForSingleObject(infoPtr->evWritable, 0) != WAIT_TIMEOUT) {
- infoPtr->writable = 1;
- needEvent = 1;
- }
- }
-
- /*
- * If READABLE watch mask is set
- * call ClearCommError to poll cbInQue
- * Window errors are ignored here
- */
- if( infoPtr->watchMask & TCL_READABLE ) {
- if( ClearCommError( infoPtr->handle, &infoPtr->error, &cStat ) ) {
- /*
- * Look for characters already pending in windows queue.
- * If they are, poll.
- */
- if( infoPtr->watchMask & TCL_READABLE ) {
- /*
- * force fileevent after serial read error
- */
- if( (cStat.cbInQue > 0) ||
- (infoPtr->error & SERIAL_READ_ERRORS) ) {
- infoPtr->readable = 1;
- time = SerialGetMilliseconds();
- if ((unsigned int) (time - infoPtr->lastEventTime)
- >= (unsigned int) infoPtr->blockTime) {
- needEvent = 1;
- infoPtr->lastEventTime = time;
- }
- }
- }
- }
- }
- /*
- * Queue an event if the serial is signaled for reading or writing.
- */
- if (needEvent) {
- infoPtr->flags |= SERIAL_PENDING;
- evPtr = (SerialEvent *) ckalloc(sizeof(SerialEvent));
- evPtr->header.proc = SerialEventProc;
- evPtr->infoPtr = infoPtr;
- Tcl_QueueEvent((Tcl_Event *) evPtr, TCL_QUEUE_TAIL);
- }
- }
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialBlockProc --
- *
- * Set blocking or non-blocking mode on channel.
- *
- * Results:
- * 0 if successful, errno when failed.
- *
- * Side effects:
- * Sets the device into blocking or non-blocking mode.
- *
- *----------------------------------------------------------------------
- */
- static int
- SerialBlockProc(
- ClientData instanceData, /* Instance data for channel. */
- int mode) /* TCL_MODE_BLOCKING or
- * TCL_MODE_NONBLOCKING. */
- {
- int errorCode = 0;
- SerialInfo *infoPtr = (SerialInfo *) instanceData;
- /*
- * Only serial READ can be switched between blocking & nonblocking
- * using COMMTIMEOUTS.
- * Serial write emulates blocking & nonblocking by the SerialWriterThread.
- */
- if (mode == TCL_MODE_NONBLOCKING) {
- infoPtr->flags |= SERIAL_ASYNC;
- } else {
- infoPtr->flags &= ~(SERIAL_ASYNC);
- }
- return errorCode;
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialCloseProc --
- *
- * Closes a serial based IO channel.
- *
- * Results:
- * 0 on success, errno otherwise.
- *
- * Side effects:
- * Closes the physical channel.
- *
- *----------------------------------------------------------------------
- */
- static int
- SerialCloseProc(
- ClientData instanceData, /* Pointer to SerialInfo structure. */
- Tcl_Interp *interp) /* For error reporting. */
- {
- SerialInfo *serialPtr = (SerialInfo *) instanceData;
- int errorCode, result = 0;
- SerialInfo *infoPtr, **nextPtrPtr;
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
- DWORD exitCode;
- errorCode = 0;
- if (serialPtr->validMask & TCL_READABLE) {
- PurgeComm(serialPtr->handle, PURGE_RXABORT | PURGE_RXCLEAR);
- CloseHandle(serialPtr->osRead.hEvent);
- }
- serialPtr->validMask &= ~TCL_READABLE;
-
- if (serialPtr->validMask & TCL_WRITABLE) {
- /*
- * Generally we cannot wait for a pending write operation
- * because it may hang due to handshake
- * WaitForSingleObject(serialPtr->evWritable, INFINITE);
- */
- /*
- * The thread may have already closed on it's own. Check it's
- * exit code.
- */
- GetExitCodeThread(serialPtr->writeThread, &exitCode);
- if (exitCode == STILL_ACTIVE) {
- /*
- * Set the stop event so that if the writer thread is
- * blocked in SerialWriterThread on WaitForMultipleEvents, it
- * will exit cleanly.
- */
- SetEvent(serialPtr->evStopWriter);
- /*
- * Wait at most 20 milliseconds for the writer thread to
- * close.
- */
- if (WaitForSingleObject(serialPtr->writeThread, 20)
- == WAIT_TIMEOUT) {
- /*
- * Forcibly terminate the background thread as a last
- * resort. Note that we need to guard against
- * terminating the thread while it is in the middle of
- * Tcl_ThreadAlert because it won't be able to release
- * the notifier lock.
- */
- Tcl_MutexLock(&serialMutex);
- /* BUG: this leaks memory */
- TerminateThread(serialPtr->writeThread, 0);
- Tcl_MutexUnlock(&serialMutex);
- }
- }
- CloseHandle(serialPtr->writeThread);
- CloseHandle(serialPtr->osWrite.hEvent);
- CloseHandle(serialPtr->evWritable);
- CloseHandle(serialPtr->evStartWriter);
- CloseHandle(serialPtr->evStopWriter);
- serialPtr->writeThread = NULL;
- PurgeComm(serialPtr->handle, PURGE_TXABORT | PURGE_TXCLEAR);
- }
- serialPtr->validMask &= ~TCL_WRITABLE;
- DeleteCriticalSection(&serialPtr->csWrite);
- /*
- * Don't close the Win32 handle if the handle is a standard channel
- * during the thread exit process. Otherwise, one thread may kill
- * the stdio of another.
- */
- if (!TclInThreadExit()
- || ((GetStdHandle(STD_INPUT_HANDLE) != serialPtr->handle)
- && (GetStdHandle(STD_OUTPUT_HANDLE) != serialPtr->handle)
- && (GetStdHandle(STD_ERROR_HANDLE) != serialPtr->handle))) {
- if (CloseHandle(serialPtr->handle) == FALSE) {
- TclWinConvertError(GetLastError());
- errorCode = errno;
- }
- }
- serialPtr->watchMask &= serialPtr->validMask;
- /*
- * Remove the file from the list of watched files.
- */
- for (nextPtrPtr = &(tsdPtr->firstSerialPtr), infoPtr = *nextPtrPtr;
- infoPtr != NULL;
- nextPtrPtr = &infoPtr->nextPtr, infoPtr = *nextPtrPtr) {
- if (infoPtr == (SerialInfo *)serialPtr) {
- *nextPtrPtr = infoPtr->nextPtr;
- break;
- }
- }
- /*
- * Wrap the error file into a channel and give it to the cleanup
- * routine.
- */
- if (serialPtr->writeBuf != NULL) {
- ckfree(serialPtr->writeBuf);
- serialPtr->writeBuf = NULL;
- }
- ckfree((char*) serialPtr);
- if (errorCode == 0) {
- return result;
- }
- return errorCode;
- }
- /*
- *----------------------------------------------------------------------
- *
- * blockingRead --
- *
- * Perform a blocking read into the buffer given. Returns
- * count of how many bytes were actually read, and an error indication.
- *
- * Results:
- * A count of how many bytes were read is returned and an error
- * indication is returned.
- *
- * Side effects:
- * Reads input from the actual channel.
- *
- *----------------------------------------------------------------------
- */
- static int
- blockingRead(
- SerialInfo *infoPtr, /* Serial info structure */
- LPVOID buf, /* The input buffer pointer */
- DWORD bufSize, /* The number of bytes to read */
- LPDWORD lpRead, /* Returns number of bytes read */
- LPOVERLAPPED osPtr ) /* OVERLAPPED structure */
- {
- /*
- * Perform overlapped blocking read.
- * 1. Reset the overlapped event
- * 2. Start overlapped read operation
- * 3. Wait for completion
- */
- /*
- * Set Offset to ZERO, otherwise NT4.0 may report an error.
- */
- osPtr->Offset = osPtr->OffsetHigh = 0;
- ResetEvent(osPtr->hEvent);
- if (! ReadFile(infoPtr->handle, buf, bufSize, lpRead, osPtr) ) {
- if (GetLastError() != ERROR_IO_PENDING) {
- /* ReadFile failed, but it isn't delayed. Report error. */
- return FALSE;
- } else {
- /* Read is pending, wait for completion, timeout ? */
- if (! GetOverlappedResult(infoPtr->handle, osPtr, lpRead, TRUE) ) {
- return FALSE;
- }
- }
- } else {
- /* ReadFile completed immediately. */
- }
- return TRUE;
- }
- /*
- *----------------------------------------------------------------------
- *
- * blockingWrite --
- *
- * Perform a blocking write from the buffer given. Returns
- * count of how many bytes were actually written, and an error indication.
- *
- * Results:
- * A count of how many bytes were written is returned and an error
- * indication is returned.
- *
- * Side effects:
- * Writes output to the actual channel.
- *
- *----------------------------------------------------------------------
- */
- static int
- blockingWrite(
- SerialInfo *infoPtr, /* Serial info structure */
- LPVOID buf, /* The output buffer pointer */
- DWORD bufSize, /* The number of bytes to write */
- LPDWORD lpWritten, /* Returns number of bytes written */
- LPOVERLAPPED osPtr ) /* OVERLAPPED structure */
- {
- int result;
- /*
- * Perform overlapped blocking write.
- * 1. Reset the overlapped event
- * 2. Remove these bytes from the output queue counter
- * 3. Start overlapped write operation
- * 3. Remove these bytes from the output queue counter
- * 4. Wait for completion
- * 5. Adjust the output queue counter
- */
- ResetEvent(osPtr->hEvent);
- EnterCriticalSection(&infoPtr->csWrite);
- infoPtr->writeQueue -= bufSize;
- /*
- * Set Offset to ZERO, otherwise NT4.0 may report an error
- */
- osPtr->Offset = osPtr->OffsetHigh = 0;
- result = WriteFile(infoPtr->handle, buf, bufSize, lpWritten, osPtr);
- LeaveCriticalSection(&infoPtr->csWrite);
- if (result == FALSE ) {
- int err = GetLastError();
- switch (err) {
- case ERROR_IO_PENDING:
- /* Write is pending, wait for completion */
- if (! GetOverlappedResult(infoPtr->handle, osPtr, lpWritten, TRUE) ) {
- return FALSE;
- }
- break;
- case ERROR_COUNTER_TIMEOUT:
- /* Write timeout handled in SerialOutputProc */
- break;
- default:
- /* WriteFile failed, but it isn't delayed. Report error */
- return FALSE;
- }
- } else {
- /* WriteFile completed immediately. */
- }
- EnterCriticalSection(&infoPtr->csWrite);
- infoPtr->writeQueue += (*lpWritten - bufSize);
- LeaveCriticalSection(&infoPtr->csWrite);
- return TRUE;
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialInputProc --
- *
- * Reads input from the IO channel into the buffer given. Returns
- * count of how many bytes were actually read, and an error indication.
- *
- * Results:
- * A count of how many bytes were read is returned and an error
- * indication is returned in an output argument.
- *
- * Side effects:
- * Reads input from the actual channel.
- *
- *----------------------------------------------------------------------
- */
- static int
- SerialInputProc(
- ClientData instanceData, /* Serial state. */
- char *buf, /* Where to store data read. */
- int bufSize, /* How much space is available
- * in the buffer? */
- int *errorCode) /* Where to store error code. */
- {
- SerialInfo *infoPtr = (SerialInfo *) instanceData;
- DWORD bytesRead = 0;
- COMSTAT cStat;
- *errorCode = 0;
- /*
- * Check if there is a CommError pending from SerialCheckProc
- */
- if( infoPtr->error & SERIAL_READ_ERRORS ){
- goto commError;
- }
- /*
- * Look for characters already pending in windows queue.
- * This is the mainly restored good old code from Tcl8.0
- */
- if( ClearCommError( infoPtr->handle, &infoPtr->error, &cStat ) ) {
- /*
- * Check for errors here, but not in the evSetup/Check procedures
- */
- if( infoPtr->error & SERIAL_READ_ERRORS ) {
- goto commError;
- }
- if( infoPtr->flags & SERIAL_ASYNC ) {
- /*
- * NON_BLOCKING mode:
- * Avoid blocking by reading more bytes than available
- * in input buffer
- */
- if( cStat.cbInQue > 0 ) {
- if( (DWORD) bufSize > cStat.cbInQue ) {
- bufSize = cStat.cbInQue;
- }
- } else {
- errno = *errorCode = EAGAIN;
- return -1;
- }
- } else {
- /*
- * BLOCKING mode:
- * Tcl trys to read a full buffer of 4 kBytes here
- */
- if( cStat.cbInQue > 0 ) {
- if( (DWORD) bufSize > cStat.cbInQue ) {
- bufSize = cStat.cbInQue;
- }
- } else {
- bufSize = 1;
- }
- }
- }
- if( bufSize == 0 ) {
- return bytesRead = 0;
- }
- /*
- * Perform blocking read. Doesn't block in non-blocking mode,
- * because we checked the number of available bytes.
- */
- if (blockingRead(infoPtr, (LPVOID) buf, (DWORD) bufSize, &bytesRead,
- &infoPtr->osRead) == FALSE) {
- goto error;
- }
- return bytesRead;
- error:
- TclWinConvertError(GetLastError());
- *errorCode = errno;
- return -1;
- commError:
- infoPtr->lastError = infoPtr->error; /* save last error code */
- infoPtr->error = 0; /* reset error code */
- *errorCode = EIO; /* to return read-error only once */
- return -1;
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialOutputProc --
- *
- * Writes the given output on the IO channel. Returns count of how
- * many characters were actually written, and an error indication.
- *
- * Results:
- * A count of how many characters were written is returned and an
- * error indication is returned in an output argument.
- *
- * Side effects:
- * Writes output on the actual channel.
- *
- *----------------------------------------------------------------------
- */
- static int
- SerialOutputProc(
- ClientData instanceData, /* Serial state. */
- CONST char *buf, /* The data buffer. */
- int toWrite, /* How many bytes to write? */
- int *errorCode) /* Where to store error code. */
- {
- SerialInfo *infoPtr = (SerialInfo *) instanceData;
- DWORD bytesWritten, timeout;
- *errorCode = 0;
- /*
- * At EXIT Tcl trys to flush all open channels in blocking mode.
- * We avoid blocking output after ExitProc or CloseHandler(chan)
- * has been called by checking the corrresponding variables.
- */
- if( ! initialized || TclInExit() ) {
- return toWrite;
- }
- /*
- * Check if there is a CommError pending from SerialCheckProc
- */
- if( infoPtr->error & SERIAL_WRITE_ERRORS ){
- infoPtr->lastError = infoPtr->error; /* save last error code */
- infoPtr->error = 0; /* reset error code */
- errno = EIO;
- goto error;
- }
- timeout = (infoPtr->flags & SERIAL_ASYNC) ? 0 : INFINITE;
- if (WaitForSingleObject(infoPtr->evWritable, timeout) == WAIT_TIMEOUT) {
- /*
- * The writer thread is blocked waiting for a write to complete
- * and the channel is in non-blocking mode.
- */
- errno = EWOULDBLOCK;
- goto error1;
- }
- /*
- * Check for a background error on the last write.
- */
- if (infoPtr->writeError) {
- TclWinConvertError(infoPtr->writeError);
- infoPtr->writeError = 0;
- goto error1;
- }
- /*
- * Remember the number of bytes in output queue
- */
- EnterCriticalSection(&infoPtr->csWrite);
- infoPtr->writeQueue += toWrite;
- LeaveCriticalSection(&infoPtr->csWrite);
- if (infoPtr->flags & SERIAL_ASYNC) {
- /*
- * The serial is non-blocking, so copy the data into the output
- * buffer and restart the writer thread.
- */
- if (toWrite > infoPtr->writeBufLen) {
- /*
- * Reallocate the buffer to be large enough to hold the data.
- */
- if (infoPtr->writeBuf) {
- ckfree(infoPtr->writeBuf);
- }
- infoPtr->writeBufLen = toWrite;
- infoPtr->writeBuf = ckalloc((unsigned int) toWrite);
- }
- memcpy(infoPtr->writeBuf, buf, (size_t) toWrite);
- infoPtr->toWrite = toWrite;
- ResetEvent(infoPtr->evWritable);
- SetEvent(infoPtr->evStartWriter);
- bytesWritten = (DWORD) toWrite;
- } else {
- /*
- * In the blocking case, just try to write the buffer directly.
- * This avoids an unnecessary copy.
- */
- if (! blockingWrite(infoPtr, (LPVOID) buf, (DWORD) toWrite,
- &bytesWritten, &infoPtr->osWrite) ) {
- goto writeError;
- }
- if (bytesWritten != (DWORD) toWrite) {
- /* Write timeout */
- infoPtr->lastError |= CE_PTO;
- errno = EIO;
- goto error;
- }
- }
- return (int) bytesWritten;
- writeError:
- TclWinConvertError(GetLastError());
- error:
- /*
- * Reset the output queue counter on error during blocking output
- */
- /*
- EnterCriticalSection(&infoPtr->csWrite);
- infoPtr->writeQueue = 0;
- LeaveCriticalSection(&infoPtr->csWrite);
- */
- error1:
- *errorCode = errno;
- return -1;
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialEventProc --
- *
- * This function is invoked by Tcl_ServiceEvent when a file event
- * reaches the front of the event queue. This procedure invokes
- * Tcl_NotifyChannel on the serial.
- *
- * Results:
- * Returns 1 if the event was handled, meaning it should be removed
- * from the queue. Returns 0 if the event was not handled, meaning
- * it should stay on the queue. The only time the event isn't
- * handled is if the TCL_FILE_EVENTS flag bit isn't set.
- *
- * Side effects:
- * Whatever the notifier callback does.
- *
- *----------------------------------------------------------------------
- */
- static int
- SerialEventProc(
- Tcl_Event *evPtr, /* Event to service. */
- int flags) /* Flags that indicate what events to
- * handle, such as TCL_FILE_EVENTS. */
- {
- SerialEvent *serialEvPtr = (SerialEvent *)evPtr;
- SerialInfo *infoPtr;
- int mask;
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
- if (!(flags & TCL_FILE_EVENTS)) {
- return 0;
- }
- /*
- * Search through the list of watched serials for the one whose handle
- * matches the event. We do this rather than simply dereferencing
- * the handle in the event so that serials can be deleted while the
- * event is in the queue.
- */
- for (infoPtr = tsdPtr->firstSerialPtr; infoPtr != NULL;
- infoPtr = infoPtr->nextPtr) {
- if (serialEvPtr->infoPtr == infoPtr) {
- infoPtr->flags &= ~(SERIAL_PENDING);
- break;
- }
- }
- /*
- * Remove stale events.
- */
- if (!infoPtr) {
- return 1;
- }
- /*
- * Check to see if the serial is readable. Note
- * that we can't tell if a serial is writable, so we always report it
- * as being writable unless we have detected EOF.
- */
- mask = 0;
- if( infoPtr->watchMask & TCL_WRITABLE ) {
- if( infoPtr->writable ) {
- mask |= TCL_WRITABLE;
- infoPtr->writable = 0;
- }
- }
- if( infoPtr->watchMask & TCL_READABLE ) {
- if( infoPtr->readable ) {
- mask |= TCL_READABLE;
- infoPtr->readable = 0;
- }
- }
- /*
- * Inform the channel of the events.
- */
- Tcl_NotifyChannel(infoPtr->channel, infoPtr->watchMask & mask);
- return 1;
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialWatchProc --
- *
- * Called by the notifier to set up to watch for events on this
- * channel.
- *
- * Results:
- * None.
- *
- * Side effects:
- * None.
- *
- *----------------------------------------------------------------------
- */
- static void
- SerialWatchProc(
- ClientData instanceData, /* Serial state. */
- int mask) /* What events to watch for, OR-ed
- * combination of TCL_READABLE,
- * TCL_WRITABLE and TCL_EXCEPTION. */
- {
- SerialInfo **nextPtrPtr, *ptr;
- SerialInfo *infoPtr = (SerialInfo *) instanceData;
- int oldMask = infoPtr->watchMask;
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
- /*
- * Since the file is always ready for events, we set the block time
- * so we will poll.
- */
- infoPtr->watchMask = mask & infoPtr->validMask;
- if (infoPtr->watchMask) {
- if (!oldMask) {
- infoPtr->nextPtr = tsdPtr->firstSerialPtr;
- tsdPtr->firstSerialPtr = infoPtr;
- }
- SerialBlockTime(infoPtr->blockTime);
- } else {
- if (oldMask) {
- /*
- * Remove the serial port from the list of watched serial ports.
- */
- for (nextPtrPtr = &(tsdPtr->firstSerialPtr), ptr = *nextPtrPtr;
- ptr != NULL;
- nextPtrPtr = &ptr->nextPtr, ptr = *nextPtrPtr) {
- if (infoPtr == ptr) {
- *nextPtrPtr = ptr->nextPtr;
- break;
- }
- }
- }
- }
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialGetHandleProc --
- *
- * Called from Tcl_GetChannelHandle to retrieve OS handles from
- * inside a command serial port based channel.
- *
- * Results:
- * Returns TCL_OK with the fd in handlePtr, or TCL_ERROR if
- * there is no handle for the specified direction.
- *
- * Side effects:
- * None.
- *
- *----------------------------------------------------------------------
- */
- static int
- SerialGetHandleProc(
- ClientData instanceData, /* The serial state. */
- int direction, /* TCL_READABLE or TCL_WRITABLE */
- ClientData *handlePtr) /* Where to store the handle. */
- {
- SerialInfo *infoPtr = (SerialInfo *) instanceData;
- *handlePtr = (ClientData) infoPtr->handle;
- return TCL_OK;
- }
- /*
- *----------------------------------------------------------------------
- *
- * SerialWriterThread --
- *
- * This function runs in a separate thread and writes data
- * onto a serial.
- *
- * Results:
- * Always returns 0.
- *
- * Side effects:
- * Signals the main thread when an output operation is completed.
- * May cause the main thread to wake up by posting a message.
- *
- *----------------------------------------------------------------------
- */
- static DWORD WINAPI
- SerialWriterThread(LPVOID arg)
- {
- SerialInfo *infoPtr = (SerialInfo *)arg;
- DWORD bytesWritten, toWrite, waitResult;
- char *buf;
- OVERLAPPED myWrite; /* have an own OVERLAPPED in this thread */
- HANDLE wEvents[2];
- /*
- * The stop event takes precedence by being first in the list.
- */
- wEvents[0] = infoPtr->evStopWriter;
- wEvents[1] = infoPtr->evStartWriter;
- for (;;) {
- /*
- * Wait for the main thread to signal before attempting to write.
- */
- waitResult = WaitForMultipleObjects(2, wEvents, FALSE, INFINITE);
- if (waitResult != (WAIT_OBJECT_0 + 1)) {
- /*
- * The start event was not signaled. It might be the stop event
- * or an error, so exit.
- */
- break;
- }
- buf = infoPtr->writeBuf;
- toWrite = infoPtr->toWrite;
- myWrite.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
- /*
- * Loop until all of the bytes are written or an error occurs.
- */
- while (toWrite > 0) {
- /*
- * Check for pending writeError
- * Ignore all write operations until the user has been notified
- */
- if (infoPtr->writeError) {
- break;
- }
- if (blockingWrite(infoPtr, (LPVOID) buf, (DWORD) toWrite,
- &bytesWritten, &myWrite) == FALSE) {
- infoPtr->writeError = GetLastError();
- break;
- }
- if (bytesWritten != toWrite) {
- /* Write timeout */
- infoPtr->writeError = ERROR_WRITE_FAULT;
- break;
- }
- toWrite -= bytesWritten;
- buf += bytesWritten;
- }
- CloseHandle(myWrite.hEvent);
- /*
- * Signal the main thread by signalling the evWritable event and
- * then waking up the notifier thread.
- */
- SetEvent(infoPtr->evWritable);
- /*
- * Alert the foreground thread. Note that we need to treat this like
- * a critical section so the foreground thread does not terminate
- * this thread while we are holding a mutex in the notifier code.
- */
- Tcl_MutexLock(&serialMutex);
- if (infoPtr->threadId != NULL) {
- /* TIP #218. When in flight ignore the event, no one will receive it anyway */
- Tcl_ThreadAlert(infoPtr->threadId);
- }
- Tcl_MutexUnlock(&serialMutex);
- }
- return 0;
- }
- /*
- *----------------------------------------------------------------------
- *
- * TclWinSerialReopen --
- *
- * Reopens the serial port with the OVERLAPPED FLAG set
- *
- * Results:
- * Returns the new handle, or INVALID_HANDLE_VALUE
- * Normally there shouldn't be any error,
- * because the same channel has previously been succeesfully opened.
- *
- * Side effects:
- * May close the original handle
- *
- *----------------------------------------------------------------------
- */
- HANDLE
- TclWinSerialReopen(handle, name, access)
- HANDLE handle;
- CONST TCHAR *name;
- DWORD access;
- {
- ThreadSpecificData *tsdPtr;
- tsdPtr = SerialInit();
- /*
- * Multithreaded I/O needs the overlapped flag set
- * otherwise ClearCommError blocks under Windows NT/2000 until serial
- * output is finished
- */
- if (CloseHandle(handle) == FALSE) {
- return INVALID_HANDLE_VALUE;
- }
- handle = (*tclWinProcs->createFileProc)(name, access,
- 0, 0, OPEN_EXISTING, FILE_FLAG_OVERLAPPED, 0);
- return handle;
- }
- /*
- *----------------------------------------------------------------------
- *
- * TclWinOpenSerialChannel --
- *
- * Constructs a Serial port channel for the specified standard OS handle.
- * This is a helper function to break up the construction of
- * channels into File, Console, or Serial.
- *
- * Results:
- * Returns the new channel, or NULL.
- *
- * Side effects:
- * May open the channel
- *
- *----------------------------------------------------------------------
- */
- Tcl_Channel
- TclWinOpenSerialChannel(handle, channelName, permissions)
- HANDLE handle;
- char *channelName;
- int permissions;
- {
- SerialInfo *infoPtr;
- DWORD id;
- SerialInit();
- infoPtr = (SerialInfo *) ckalloc((unsigned) sizeof(SerialInfo));
- memset(infoPtr, 0, sizeof(SerialInfo));
- infoPtr->validMask = permissions;
- infoPtr->handle = handle;
- infoPtr->channel = (Tcl_Channel) NULL;
- infoPtr->readable = 0;
- infoPtr->writable = 1;
- infoPtr->toWrite = infoPtr->writeQueue = 0;
- infoPtr->blockTime = SERIAL_DEFAULT_BLOCKTIME;
- infoPtr->lastEventTime = 0;
- infoPtr->lastError = infoPtr->error = 0;
- infoPtr->threadId = Tcl_GetCurrentThread();
- infoPtr->sysBufRead = 4096;
- infoPtr->sysBufWrite = 4096;
- /*
- * Use the pointer to keep the channel names unique, in case
- * the handles are shared between multiple channels (stdin/stdout).
- */
- wsprintfA(channelName, "file%lx", (int) infoPtr);
- infoPtr->channel = Tcl_CreateChannel(&serialChannelType, channelName,
- (ClientData) infoPtr, permissions);
- SetupComm(handle, infoPtr->sysBufRead, infoPtr->sysBufWrite);
- PurgeComm(handle, PURGE_TXABORT | PURGE_RXABORT | PURGE_TXCLEAR
- | PURGE_RXCLEAR);
- /*
- * default is blocking
- */
- SetCommTimeouts(handle, &no_timeout);
- InitializeCriticalSection(&infoPtr->csWrite);
- if (permissions & TCL_READABLE) {
- infoPtr->osRead.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
- }
- if (permissions & TCL_WRITABLE) {
- /*
- * Initially the channel is writable
- * and the writeThread is idle.
- */
- infoPtr->osWrite.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
- infoPtr->evWritable = CreateEvent(NULL, TRUE, TRUE, NULL);
- infoPtr->evStartWriter = CreateEvent(NULL, FALSE, FALSE, NULL);
- infoPtr->evStopWriter = CreateEvent(NULL, FALSE, FALSE, NULL);
- infoPtr->writeThread = CreateThread(NULL, 256, SerialWriterThread,
- infoPtr, 0, &id);
- }
- /*
- * Files have default translation of AUTO and ^Z eof char, which
- * means that a ^Z will be accepted as EOF when reading.
- */
- Tcl_SetChannelOption(NULL, infoPtr->channel, "-translation", "auto");
- Tcl_SetChannelOption(NULL, infoPtr->channel, "-eofchar", "