Tcl package Thread source code

    struct ThreadSendData *sendData;      /* See below */
    struct ThreadClbkData *clbkData;      /* See below */
    struct ThreadEventResult *resultPtr;  /* To communicate the result back.
                                           * NULL if we don't care about it */
} ThreadEvent;

typedef int  (ThreadSendProc) (Tcl_Interp*, ClientData);
typedef void (ThreadSendFree) (ClientData);

static ThreadSendProc ThreadSendEval;     /* Does a regular Tcl_Eval */
static ThreadSendProc ThreadClbkSetVar;   /* Sets the named variable */

/*
 * These structures are used to communicate commands between source and target
 * threads. The ThreadSendData is used for source->target command passing,
 * while the ThreadClbkData is used for doing asynchronous callbacks.
 *
 * Important: structures below must have first three elements identical!
 */

typedef struct ThreadSendData {
    ThreadSendProc *execProc;             /* Func to exec in remote thread */
    ClientData clientData;                /* Ptr to pass to send function */
    ThreadSendFree *freeProc;             /* Function to free client data */
     /* ---- */
    Tcl_Interp *interp;                   /* Interp to run the command */
} ThreadSendData;

typedef struct ThreadClbkData {
    ThreadSendProc *execProc;             /* The callback function */
    ClientData clientData;                /* Ptr to pass to clbk function */
    ThreadSendFree *freeProc;             /* Function to free client data */
    /* ---- */
    Tcl_Interp *interp;                   /* Interp to run the command */
    Tcl_ThreadId threadId;                /* Thread where to post callback */
    ThreadEventResult result;             /* Returns result asynchronously */
} ThreadClbkData;

/*

 *
 * Side effects:
 *  None.
 *
 *----------------------------------------------------------------------
 */

static void
threadSendFree(ClientData ptr)
{
    ckfree((char *)ptr);
}

static int
ThreadSendObjCmd(
    ClientData  dummy,         /* Not used. */
    Tcl_Interp *interp,        /* Current interpreter. */
    int         objc,          /* Number of arguments. */
    Tcl_Obj    *const objv[]   /* Argument objects. */
) {

         * Prepare record for the callback. This is asynchronously
         * posted back to us when the target thread finishes processing.
         * We should do a vwait on the "var" to get notified.
         */

        clbkPtr = (ThreadClbkData*)ckalloc(sizeof(ThreadClbkData));
        clbkPtr->execProc   = ThreadClbkSetVar;
        clbkPtr->freeProc   = threadSendFree;
        clbkPtr->interp     = interp;
        clbkPtr->threadId   = Tcl_GetCurrentThread();
        clbkPtr->clientData = memcpy(ckalloc(vsize), varName, vsize);
    }

    /*
     * Prepare job record for the target thread
     */

    sendPtr = (ThreadSendData*)ckalloc(sizeof(ThreadSendData));
    sendPtr->interp     = NULL; /* Signal to use thread main interp */
    sendPtr->execProc   = ThreadSendEval;
    sendPtr->freeProc   = threadSendFree;
    sendPtr->clientData = memcpy(ckalloc(size), script, size);

    ret = ThreadSend(interp, thrId, sendPtr, clbkPtr, flags);

    if (var && (flags & THREAD_SEND_WAIT)) {

        /*

    /*
     * Prepare the structure with the job description
     * to be sent asynchronously to each known thread.
     */

    job.interp     = NULL; /* Signal to use thread's main interp */
    job.execProc   = ThreadSendEval;
    job.freeProc   = threadSendFree;
    job.clientData = NULL;

    /*
     * Now, circle this list and send each thread the script.
     * This is sent asynchronously, since we do not care what
     * are they going to do with it. Also, the event is queued
     * to the head of the event queue (as out-of-band message).

        ThreadGetHandle(Tcl_GetCurrentThread(), buf);
        argv[0] = errorProcString;
        argv[1] = buf;
        argv[2] = errorInfo;

        sendPtr = (ThreadSendData*)ckalloc(sizeof(ThreadSendData));
        sendPtr->execProc   = ThreadSendEval;
        sendPtr->freeProc   = threadSendFree;
        sendPtr->clientData = Tcl_Merge(3, argv);
        sendPtr->interp     = NULL;

        ThreadSend(interp, errorThreadId, sendPtr, NULL, 0);
    }
}


     * This will free send and/or callback structures
     * since both are the same in the beginning.
     */

    ThreadSendData *anyPtr = (ThreadSendData*)clientData;

    if (anyPtr) {
        if (anyPtr->clientData) {
            (*anyPtr->freeProc)(anyPtr->clientData);
        }
        ckfree((char*)anyPtr);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * ThreadDeleteEvent --