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Diffstat (limited to 'win/tclWinSerial.c')
| -rw-r--r-- | win/tclWinSerial.c | 1401 |
1 files changed, 1401 insertions, 0 deletions
diff --git a/win/tclWinSerial.c b/win/tclWinSerial.c new file mode 100644 index 0000000..733da67 --- /dev/null +++ b/win/tclWinSerial.c @@ -0,0 +1,1401 @@ +/* + * 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. + * + * RCS: @(#) $Id: tclWinSerial.c,v 1.2 1999/04/16 00:48:09 stanton Exp $ + */ + +#include "tclWinInt.h" + +#include <dos.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_EXTRABYTE (1<<3) /* Extra byte consumed while waiting for data */ +/* + * 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. */ + Tcl_ThreadId threadId; /* Thread to which events should be reported. + * This value is used by the reader/writer + * threads. */ + HANDLE writeThread; /* Handle to writer thread. */ + HANDLE readThread; /* Handle to reader thread. */ + HANDLE writable; /* Manual-reset event to signal when the + * writer thread has finished waiting for + * the current buffer to be written. */ + HANDLE readable; /* Manual-reset event to signal when the + * reader thread has finished waiting for + * input. */ + HANDLE startWriter; /* Auto-reset event used by the main thread to + * signal when the writer thread should attempt + * to write to the serial. */ + HANDLE startReader; /* Auto-reset event used by the main thread to + * signal when the reader thread should attempt + * to read from the serial. */ + 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 writable object. + */ + char *writeBuf; /* Current background output buffer. + * Access is synchronized with the writable + * object. */ + int writeBufLen; /* Size of write buffer. Access is + * synchronized with the writable + * object. */ + int toWrite; /* Current amount to be written. Access is + * synchronized with the writable object. */ + int readFlags; /* Flags that are shared with the reader + * thread. Access is synchronized with the + * readable object. */ + int writeFlags; /* Flags that are shared with the writer + * thread. Access is synchronized with the + * readable object. */ + int readyMask; /* Events that need to be checked on. */ + char extraByte; + +} 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; + +/* + * 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, char *buf, + int toWrite, int *errorCode); +static DWORD WINAPI SerialReaderThread(LPVOID arg); +static void SerialSetupProc(ClientData clientData, int flags); +static void SerialWatchProc(ClientData instanceData, int mask); +static DWORD WINAPI SerialWriterThread(LPVOID arg); +static void ProcExitHandler(ClientData clientData); +static int WaitForRead(SerialInfo *infoPtr, int blocking); +static int SerialGetOptionProc _ANSI_ARGS_((ClientData instanceData, + Tcl_Interp *interp, char *optionName, + Tcl_DString *dsPtr)); +static int SerialSetOptionProc _ANSI_ARGS_((ClientData instanceData, + Tcl_Interp *interp, char *optionName, + char *value)); + +/* + * This structure describes the channel type structure for command serial + * based IO. + */ + +static Tcl_ChannelType serialChannelType = { + "serial", /* Type name. */ + SerialBlockProc, /* Set blocking or non-blocking mode.*/ + 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. */ +}; + +/* + *---------------------------------------------------------------------- + * + * 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 */ +{ + 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); +} + +/* + *---------------------------------------------------------------------- + * + * 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; + Tcl_Time blockTime = { 0, 0 }; + int block = 1; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + if (!(flags & TCL_FILE_EVENTS)) { + return; + } + + /* + * Look to see if any events are already pending. If they are, poll. + */ + + for (infoPtr = tsdPtr->firstSerialPtr; infoPtr != NULL; + infoPtr = infoPtr->nextPtr) { + if (infoPtr->watchMask & TCL_WRITABLE) { + if (WaitForSingleObject(infoPtr->writable, 0) != WAIT_TIMEOUT) { + block = 0; + } + } + if (infoPtr->watchMask & TCL_READABLE) { + if (WaitForRead(infoPtr, 0) >= 0) { + block = 0; + } + } + } + if (!block) { + Tcl_SetMaxBlockTime(&blockTime); + } +} + +/* + *---------------------------------------------------------------------- + * + * 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); + + 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; + } + + /* + * Queue an event if the serial is signaled for reading or writing. + */ + + needEvent = 0; + if (infoPtr->watchMask & TCL_WRITABLE) { + if (WaitForSingleObject(infoPtr->writable, 0) != WAIT_TIMEOUT) { + needEvent = 1; + } + } + + if (infoPtr->watchMask & TCL_READABLE) { + if (WaitForRead(infoPtr, 0) >= 0) { + needEvent = 1; + } + } + + 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. */ +{ + SerialInfo *infoPtr = (SerialInfo *) instanceData; + + /* + * Serial IO on Windows can not be switched between blocking & nonblocking, + * hence we have to emulate the behavior. This is done in the input + * function by checking against a bit in the state. We set or unset the + * bit here to cause the input function to emulate the correct behavior. + */ + + if (mode == TCL_MODE_NONBLOCKING) { + infoPtr->flags |= SERIAL_ASYNC; + } else { + infoPtr->flags &= ~(SERIAL_ASYNC); + } + return 0; +} + +/* + *---------------------------------------------------------------------- + * + * 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); + + errorCode = 0; + if (serialPtr->readThread) { + /* + * Forcibly terminate the background thread. We cannot rely on the + * thread to cleanly terminate itself because we have no way of + * closing the handle without blocking in the case where the + * thread is in the middle of an I/O operation. 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); + TerminateThread(serialPtr->readThread, 0); + Tcl_MutexUnlock(&serialMutex); + + /* + * Wait for the thread to terminate. This ensures that we are + * completely cleaned up before we leave this function. + */ + + WaitForSingleObject(serialPtr->readThread, INFINITE); + CloseHandle(serialPtr->readThread); + CloseHandle(serialPtr->readable); + CloseHandle(serialPtr->startReader); + serialPtr->readThread = NULL; + } + serialPtr->validMask &= ~TCL_READABLE; + + if (serialPtr->writeThread) { + WaitForSingleObject(serialPtr->writable, INFINITE); + + /* + * Forcibly terminate the background thread. We cannot rely on the + * thread to cleanly terminate itself because we have no way of + * closing the handle without blocking in the case where the + * thread is in the middle of an I/O operation. 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); + TerminateThread(serialPtr->writeThread, 0); + Tcl_MutexUnlock(&serialMutex); + + /* + * Wait for the thread to terminate. This ensures that we are + * completely cleaned up before we leave this function. + */ + + WaitForSingleObject(serialPtr->writeThread, INFINITE); + CloseHandle(serialPtr->writeThread); + CloseHandle(serialPtr->writable); + CloseHandle(serialPtr->startWriter); + serialPtr->writeThread = NULL; + } + serialPtr->validMask &= ~TCL_WRITABLE; + + /* + * Don't close the Win32 handle if the handle is a standard channel + * during the exit process. Otherwise, one thread may kill the stdio + * of another. + */ + + if (!TclInExit() + || ((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; +} + +/* + *---------------------------------------------------------------------- + * + * 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; + int result; + DWORD err; + + *errorCode = 0; + + /* + * Synchronize with the reader thread. + */ + + result = WaitForRead(infoPtr, (infoPtr->flags & SERIAL_ASYNC) ? 0 : 1); + + /* + * If an error occurred, return immediately. + */ + + if (result == -1) { + *errorCode = errno; + return -1; + } + + if (infoPtr->readFlags & SERIAL_EXTRABYTE) { + + /* + * If a byte was consumed waiting, then put it in the buffer. + */ + + *buf = infoPtr->extraByte; + infoPtr->readFlags &= ~SERIAL_EXTRABYTE; + buf++; + bufSize--; + bytesRead = 1; + + if (result == 0) { + return bytesRead; + } + } + + if (ReadFile(infoPtr->handle, (LPVOID) buf, (DWORD) bufSize, &bytesRead, + NULL) == FALSE) { + err = GetLastError(); + if (err != ERROR_IO_PENDING) { + goto error; + } + } + + return bytesRead; + + error: + TclWinConvertError(GetLastError()); + *errorCode = errno; + 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. */ + 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, err; + + *errorCode = 0; + timeout = (infoPtr->flags & SERIAL_ASYNC) ? 0 : INFINITE; + if (WaitForSingleObject(infoPtr->writable, timeout) == WAIT_TIMEOUT) { + /* + * The writer thread is blocked waiting for a write to complete + * and the channel is in non-blocking mode. + */ + + errno = EAGAIN; + goto error; + } + + /* + * Check for a background error on the last write. + */ + + if (infoPtr->writeError) { + TclWinConvertError(infoPtr->writeError); + infoPtr->writeError = 0; + goto error; + } + + 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(toWrite); + } + memcpy(infoPtr->writeBuf, buf, toWrite); + infoPtr->toWrite = toWrite; + ResetEvent(infoPtr->writable); + SetEvent(infoPtr->startWriter); + bytesWritten = toWrite; + } else { + /* + * In the blocking case, just try to write the buffer directly. + * This avoids an unnecessary copy. + */ + if (WriteFile(infoPtr->handle, (LPVOID) buf, (DWORD) toWrite, + &bytesWritten, NULL) == FALSE) { + err = GetLastError(); + if (err != ERROR_IO_PENDING) { + TclWinConvertError(GetLastError()); + goto error; + } + } + } + return bytesWritten; + + error: + *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 (WaitForSingleObject(infoPtr->writable, 0) != WAIT_TIMEOUT) { + mask = TCL_WRITABLE; + } + } + + if (infoPtr->watchMask & TCL_READABLE) { + if (WaitForRead(infoPtr, 0) >= 0) { + if (infoPtr->readFlags & SERIAL_EOF) { + mask = TCL_READABLE; + } else { + mask |= TCL_READABLE; + } + } + } + + /* + * 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 + * to zero so we will poll. + */ + + infoPtr->watchMask = mask & infoPtr->validMask; + if (infoPtr->watchMask) { + Tcl_Time blockTime = { 0, 0 }; + if (!oldMask) { + infoPtr->nextPtr = tsdPtr->firstSerialPtr; + tsdPtr->firstSerialPtr = infoPtr; + } + Tcl_SetMaxBlockTime(&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; +} + +/* + *---------------------------------------------------------------------- + * + * WaitForRead -- + * + * Wait until some data is available, the serial is at + * EOF or the reader thread is blocked waiting for data (if the + * channel is in non-blocking mode). + * + * Results: + * Returns 1 if serial is readable. Returns 0 if there is no data + * on the serial, but there is buffered data. Returns -1 if an + * error occurred. If an error occurred, the threads may not + * be synchronized. + * + * Side effects: + * Updates the shared state flags and may consume 1 byte of data + * from the serial. If no error occurred, the reader thread is + * blocked waiting for a signal from the main thread. + * + *---------------------------------------------------------------------- + */ + +static int +WaitForRead( + SerialInfo *infoPtr, /* Serial state. */ + int blocking) /* Indicates whether call should be + * blocking or not. */ +{ + DWORD timeout, errors; + HANDLE *handle = infoPtr->handle; + COMSTAT stat; + + while (1) { + /* + * Synchronize with the reader thread. + */ + + timeout = blocking ? INFINITE : 0; + if (WaitForSingleObject(infoPtr->readable, timeout) == WAIT_TIMEOUT) { + /* + * The reader thread is blocked waiting for data and the channel + * is in non-blocking mode. + */ + + errno = EAGAIN; + return -1; + } + + /* + * At this point, the two threads are synchronized, so it is safe + * to access shared state. This code is not called in the ReaderThread + * in blocking mode, so it needs to be checked here. + */ + + /* + * If the serial has hit EOF, it is always readable. + */ + + if (infoPtr->readFlags & SERIAL_EOF) { + return 1; + } + + if (ClearCommError(infoPtr->handle, &errors, &stat)) { + /* + * If there are errors, then signal an I/O error. + */ + + if (errors != 0) { + errno = EIO; + return -1; + } + } + + /* + * If data is in the queue return 1 + */ + + if (stat.cbInQue != 0) { + return 1; + } + + /* + * if there is an extra byte that was consumed while + * waiting, but no data in the queue, return 0 + */ + + if (infoPtr->readFlags & SERIAL_EXTRABYTE) { + return 0; + } + + ResetEvent(infoPtr->readable); + SetEvent(infoPtr->startReader); + } +} + +/* + *---------------------------------------------------------------------- + * + * SerialReaderThread -- + * + * This function runs in a separate thread and waits for input + * to become available on a serial. + * + * Results: + * None. + * + * Side effects: + * Signals the main thread when input become available. May + * cause the main thread to wake up by posting a message. May + * consume one byte from the serial for each wait operation. + * + *---------------------------------------------------------------------- + */ + +static DWORD WINAPI +SerialReaderThread(LPVOID arg) +{ + SerialInfo *infoPtr = (SerialInfo *)arg; + HANDLE *handle = infoPtr->handle; + DWORD mask = EV_RXCHAR; + DWORD count; + + for (;;) { + /* + * Wait for the main thread to signal before attempting to wait. + */ + + WaitForSingleObject(infoPtr->startReader, INFINITE); + + /* + * Try waiting for a Comm event. + */ + + WaitCommEvent(handle, NULL, NULL); + + + /* + * try to read one byte + */ + + if (ReadFile(handle, &(infoPtr->extraByte), 1, &count, NULL) + != FALSE) { + + /* + * one byte was consumed while waiting to read, keep it + */ + + if (count != 0) { + infoPtr->readFlags |= SERIAL_EXTRABYTE; + } + + } else { + /* + * There is an error, signal an EOF. + */ + + infoPtr->readFlags |= SERIAL_EOF; + } + + /* + * Signal the main thread by signalling the readable event and + * then waking up the notifier thread. + */ + + SetEvent(infoPtr->readable); + + /* + * 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); + Tcl_ThreadAlert(infoPtr->threadId); + Tcl_MutexUnlock(&serialMutex); + } + return 0; /* NOT REACHED */ +} + +/* + *---------------------------------------------------------------------- + * + * 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; + HANDLE *handle = infoPtr->handle; + DWORD count, toWrite, err; + char *buf; + + for (;;) { + /* + * Wait for the main thread to signal before attempting to write. + */ + + WaitForSingleObject(infoPtr->startWriter, INFINITE); + + buf = infoPtr->writeBuf; + toWrite = infoPtr->toWrite; + + /* + * Loop until all of the bytes are written or an error occurs. + */ + + while (toWrite > 0) { + if (WriteFile(handle, (LPVOID) buf, (DWORD) toWrite, + &count, NULL) == FALSE) { + err = GetLastError(); + if (err != ERROR_IO_PENDING) { + TclWinConvertError(GetLastError()); + infoPtr->writeError = err; + break; + } + } else { + toWrite -= count; + buf += count; + } + } + + /* + * Signal the main thread by signalling the writable event and + * then waking up the notifier thread. + */ + + SetEvent(infoPtr->writable); + + /* + * 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); + Tcl_ThreadAlert(infoPtr->threadId); + Tcl_MutexUnlock(&serialMutex); + } + return 0; /* NOT REACHED */ +} + + + +/* + *---------------------------------------------------------------------- + * + * 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; + COMMTIMEOUTS cto; + ThreadSpecificData *tsdPtr; + DWORD id; + + tsdPtr = SerialInit(); + + SetCommMask(handle, EV_RXCHAR); + SetupComm(handle, 4096, 4096); + PurgeComm(handle, PURGE_TXABORT | PURGE_RXABORT | PURGE_TXCLEAR + | PURGE_RXCLEAR); + cto.ReadIntervalTimeout = MAXDWORD; + cto.ReadTotalTimeoutMultiplier = MAXDWORD; + cto.ReadTotalTimeoutConstant = 1; + cto.WriteTotalTimeoutMultiplier = 0; + cto.WriteTotalTimeoutConstant = 0; + SetCommTimeouts(handle, &cto); + + infoPtr = (SerialInfo *) ckalloc((unsigned) sizeof(SerialInfo)); + memset(infoPtr, 0, sizeof(SerialInfo)); + + infoPtr->validMask = permissions; + infoPtr->handle = handle; + + /* + * 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); + + + infoPtr->threadId = Tcl_GetCurrentThread(); + + if (permissions & TCL_READABLE) { + infoPtr->readable = CreateEvent(NULL, TRUE, TRUE, NULL); + infoPtr->startReader = CreateEvent(NULL, FALSE, FALSE, NULL); + infoPtr->readThread = CreateThread(NULL, 8000, SerialReaderThread, + infoPtr, 0, &id); + } + if (permissions & TCL_WRITABLE) { + infoPtr->writable = CreateEvent(NULL, TRUE, TRUE, NULL); + infoPtr->startWriter = CreateEvent(NULL, FALSE, FALSE, NULL); + infoPtr->writeThread = CreateThread(NULL, 8000, 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", "\032 {}"); + + return infoPtr->channel; +} + +/* + *---------------------------------------------------------------------- + * + * SerialSetOptionProc -- + * + * Sets an option on a channel. + * + * Results: + * A standard Tcl result. Also sets the interp's result on error if + * interp is not NULL. + * + * Side effects: + * May modify an option on a device. + * + *---------------------------------------------------------------------- + */ + +static int +SerialSetOptionProc(instanceData, interp, optionName, value) + ClientData instanceData; /* File state. */ + Tcl_Interp *interp; /* For error reporting - can be NULL. */ + char *optionName; /* Which option to set? */ + char *value; /* New value for option. */ +{ + SerialInfo *infoPtr; + DCB dcb; + int len; + BOOL result; + Tcl_DString ds; + TCHAR *native; + + infoPtr = (SerialInfo *) instanceData; + + len = strlen(optionName); + if ((len > 1) && (strncmp(optionName, "-mode", len) == 0)) { + if (GetCommState(infoPtr->handle, &dcb)) { + native = Tcl_WinUtfToTChar(value, -1, &ds); + result = (*tclWinProcs->buildCommDCBProc)(native, &dcb); + Tcl_DStringFree(&ds); + + if ((result == FALSE) || + (SetCommState(infoPtr->handle, &dcb) == FALSE)) { + /* + * one should separate the 2 errors... + */ + + if (interp) { + Tcl_AppendResult(interp, "bad value for -mode: should be ", + "baud,parity,data,stop", NULL); + } + return TCL_ERROR; + } else { + return TCL_OK; + } + } else { + if (interp) { + Tcl_AppendResult(interp, "can't get comm state", NULL); + } + return TCL_ERROR; + } + } else { + return Tcl_BadChannelOption(interp, optionName, "mode"); + } +} + +/* + *---------------------------------------------------------------------- + * + * SerialGetOptionProc -- + * + * Gets a mode associated with an IO channel. If the optionName arg + * is non NULL, retrieves the value of that option. If the optionName + * arg is NULL, retrieves a list of alternating option names and + * values for the given channel. + * + * Results: + * A standard Tcl result. Also sets the supplied DString to the + * string value of the option(s) returned. + * + * Side effects: + * The string returned by this function is in static storage and + * may be reused at any time subsequent to the call. + * + *---------------------------------------------------------------------- + */ +static int +SerialGetOptionProc(instanceData, interp, optionName, dsPtr) + ClientData instanceData; /* File state. */ + Tcl_Interp *interp; /* For error reporting - can be NULL. */ + char *optionName; /* Option to get. */ + Tcl_DString *dsPtr; /* Where to store value(s). */ +{ + SerialInfo *infoPtr; + DCB dcb; + int len; + + infoPtr = (SerialInfo *) instanceData; + + if (optionName == NULL) { + Tcl_DStringAppendElement(dsPtr, "-mode"); + len = 0; + } else { + len = strlen(optionName); + } + if ((len == 0) || + ((len > 1) && (strncmp(optionName, "-mode", len) == 0))) { + if (GetCommState(infoPtr->handle, &dcb) == 0) { + /* + * shouldn't we flag an error instead ? + */ + + Tcl_DStringAppendElement(dsPtr, ""); + + } else { + char parity; + char *stop; + char buf[2 * TCL_INTEGER_SPACE + 16]; + + parity = 'n'; + if (dcb.Parity < 4) { + parity = "noems"[dcb.Parity]; + } + + stop = (dcb.StopBits == ONESTOPBIT) ? "1" : + (dcb.StopBits == ONE5STOPBITS) ? "1.5" : "2"; + + wsprintfA(buf, "%d,%c,%d,%s", dcb.BaudRate, parity, dcb.ByteSize, + stop); + Tcl_DStringAppendElement(dsPtr, buf); + } + return TCL_OK; + } else { + return Tcl_BadChannelOption(interp, optionName, "mode"); + } +} |