ntthread.c

Netscape NSPR库源码

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 
 * The contents of this file are subject to the Mozilla Public
 * License Version 1.1 (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.mozilla.org/MPL/
 * 
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 * 
 * The Original Code is the Netscape Portable Runtime (NSPR).
 * 
 * The Initial Developer of the Original Code is Netscape
 * Communications Corporation.  Portions created by Netscape are 
 * Copyright (C) 1998-2000 Netscape Communications Corporation.  All
 * Rights Reserved.
 * 
 * Contributor(s):
 * 
 * Alternatively, the contents of this file may be used under the
 * terms of the GNU General Public License Version 2 or later (the
 * "GPL"), in which case the provisions of the GPL are applicable 
 * instead of those above.  If you wish to allow use of your 
 * version of this file only under the terms of the GPL and not to
 * allow others to use your version of this file under the MPL,
 * indicate your decision by deleting the provisions above and
 * replace them with the notice and other provisions required by
 * the GPL.  If you do not delete the provisions above, a recipient
 * may use your version of this file under either the MPL or the
 * GPL.
 */

#include "primpl.h"
#include <process.h>  /* for _beginthreadex() */

extern void _PR_Win32InitTimeZone(void);  /* defined in ntmisc.c */

/* --- globals ------------------------------------------------ */
PRLock                       *_pr_schedLock = NULL;
_PRInterruptTable             _pr_interruptTable[] = { { 0 } };

BOOL _pr_use_static_tls = TRUE;
__declspec(thread) PRThread  *_pr_current_fiber;
__declspec(thread) PRThread  *_pr_fiber_last_run;
__declspec(thread) _PRCPU    *_pr_current_cpu;
__declspec(thread) PRUintn    _pr_ints_off;
DWORD _pr_currentFiberIndex;
DWORD _pr_lastFiberIndex;
DWORD _pr_currentCPUIndex;
DWORD _pr_intsOffIndex;

_MDLock                       _nt_idleLock;
PRCList                       _nt_idleList;
PRUint32                        _nt_idleCount;

extern __declspec(thread) PRThread *_pr_io_restarted_io;
extern DWORD _pr_io_restartedIOIndex;

/* Must check the restarted_io *before* decrementing no_sched to 0 */
#define POST_SWITCH_WORK() \
    PR_BEGIN_MACRO \
        PRThread *restarted_io = \
            (_pr_use_static_tls ? _pr_io_restarted_io \
            : (PRThread *) TlsGetValue(_pr_io_restartedIOIndex)); \
        if (restarted_io) { \
            _nt_handle_restarted_io(restarted_io); \
        } \
        _PR_MD_LAST_THREAD()->no_sched = 0; \
    PR_END_MACRO

void
_nt_handle_restarted_io(PRThread *restarted_io)
{
    /* After the switch we can resume an IO if needed.
     * XXXMB - this needs to be done in create thread, since that could
     * be the result for a context switch too..
     */
    PR_ASSERT(restarted_io->io_suspended == PR_TRUE);
    PR_ASSERT(restarted_io->md.thr_bound_cpu == restarted_io->cpu);

    _PR_THREAD_LOCK(restarted_io);
    if (restarted_io->io_pending == PR_FALSE) {

        /* The IO already completed, put us back on the runq. */
        int pri = restarted_io->priority;

        restarted_io->state = _PR_RUNNABLE;
        _PR_RUNQ_LOCK(restarted_io->cpu);
        _PR_ADD_RUNQ(restarted_io, restarted_io->cpu, pri);
        _PR_RUNQ_UNLOCK(restarted_io->cpu);
    } else {
        _PR_SLEEPQ_LOCK(restarted_io->cpu);
        _PR_ADD_SLEEPQ(restarted_io, restarted_io->sleep);
        _PR_SLEEPQ_UNLOCK(restarted_io->cpu);
    }
    restarted_io->io_suspended = PR_FALSE;
    restarted_io->md.thr_bound_cpu = NULL;

    _PR_THREAD_UNLOCK(restarted_io);

    if (_pr_use_static_tls) {
        _pr_io_restarted_io = NULL;
    } else {
        TlsSetValue(_pr_io_restartedIOIndex, NULL);
    }
}

void
_PR_MD_EARLY_INIT()
{
    _MD_NEW_LOCK( &_nt_idleLock );
    _nt_idleCount = 0;
    PR_INIT_CLIST(&_nt_idleList);
    _PR_Win32InitTimeZone();

#if 0
    /* Make the clock tick at least once per millisecond */
    if ( timeBeginPeriod(1) == TIMERR_NOCANDO) {
        /* deep yoghurt; clock doesn't tick fast enough! */
        PR_ASSERT(0);
    }
#endif

    if (!_pr_use_static_tls) {
        _pr_currentFiberIndex = TlsAlloc();
        _pr_lastFiberIndex = TlsAlloc();
        _pr_currentCPUIndex = TlsAlloc();
        _pr_intsOffIndex = TlsAlloc();
        _pr_io_restartedIOIndex = TlsAlloc();
    }
}

void _PR_MD_CLEANUP_BEFORE_EXIT(void)
{
    _PR_NT_FreeSids();

    WSACleanup();

    if (!_pr_use_static_tls) {
        TlsFree(_pr_currentFiberIndex);
        TlsFree(_pr_lastFiberIndex);
        TlsFree(_pr_currentCPUIndex);
        TlsFree(_pr_intsOffIndex);
        TlsFree(_pr_io_restartedIOIndex);
    }
}

PRStatus
_PR_MD_INIT_THREAD(PRThread *thread)
{
    thread->md.overlapped.ioModel = _MD_BlockingIO;
    thread->md.overlapped.data.mdThread = &thread->md;

    if (thread->flags & _PR_GLOBAL_SCOPE) {
        if (thread->flags & (_PR_PRIMORDIAL | _PR_ATTACHED)) {
            /*
            ** Warning:
            ** --------
            ** NSPR requires a real handle to every thread.
            ** GetCurrentThread() returns a pseudo-handle which
            ** is not suitable for some thread operations (e.g.,
            ** suspending).  Therefore, get a real handle from
            ** the pseudo handle via DuplicateHandle(...)
            */
            DuplicateHandle(
                    GetCurrentProcess(),     /* Process of source handle */
                    GetCurrentThread(),      /* Pseudo Handle to dup */
                    GetCurrentProcess(),     /* Process of handle */
                    &(thread->md.handle),    /* resulting handle */
                    0L,                      /* access flags */
                    FALSE,                   /* Inheritable */
                    DUPLICATE_SAME_ACCESS);  /* Options */
        }

        /* Create the blocking IO semaphore */
        thread->md.blocked_sema = CreateSemaphore(NULL, 0, 1, NULL);
        if (thread->md.blocked_sema == NULL) {
            return PR_FAILURE;
        }
		if (_native_threads_only) {
			/* Create the blocking IO semaphore */
			thread->md.thr_event = CreateEvent(NULL, TRUE, FALSE, NULL);
			if (thread->md.thr_event == NULL) {
				return PR_FAILURE;
			}
		}
    }

    return PR_SUCCESS;
}

PRStatus 
_PR_MD_CREATE_THREAD(PRThread *thread, 
                  void (*start)(void *), 
                  PRThreadPriority priority, 
                  PRThreadScope scope, 
                  PRThreadState state, 
                  PRUint32 stackSize)
{

#if 0
    thread->md.handle = CreateThread(
                    NULL,                             /* security attrib */
                    thread->stack->stackSize,         /* stack size      */
                    (LPTHREAD_START_ROUTINE)start,    /* startup routine */
                    (void *)thread,                   /* thread param    */
                    CREATE_SUSPENDED,                 /* create flags    */
                    &(thread->id) );                  /* thread id       */
#else
    thread->md.handle = (HANDLE) _beginthreadex(
                    NULL,
                    thread->stack->stackSize,
                    (unsigned (__stdcall *)(void *))start,
                    (void *)thread,
                    CREATE_SUSPENDED,
                    &(thread->id));
#endif
    if(!thread->md.handle) {
        PRErrorCode prerror;
        thread->md.fiber_last_error = GetLastError();
        switch (errno) {
            case ENOMEM:
                prerror = PR_OUT_OF_MEMORY_ERROR;
                break;
            case EAGAIN:
                prerror = PR_INSUFFICIENT_RESOURCES_ERROR;
                break;
            case EINVAL:
                prerror = PR_INVALID_ARGUMENT_ERROR;
                break;
            default:
                prerror = PR_UNKNOWN_ERROR;
        }
        PR_SetError(prerror, errno);
        return PR_FAILURE;
    }

    thread->md.id = thread->id;
    /*
     * On windows, a thread is created with a thread priority of
     * THREAD_PRIORITY_NORMAL.
     */
    if (priority != PR_PRIORITY_NORMAL) {
        _PR_MD_SET_PRIORITY(&(thread->md), priority);
    }

    /* Activate the thread */
    if ( ResumeThread( thread->md.handle ) != -1)
        return PR_SUCCESS;

    PR_SetError(PR_UNKNOWN_ERROR, GetLastError());
    return PR_FAILURE;
}

void
_PR_MD_JOIN_THREAD(_MDThread *md)
{
    DWORD rv;

    rv = WaitForSingleObject(md->handle, INFINITE);
    PR_ASSERT(WAIT_OBJECT_0 == rv);
}

void
_PR_MD_END_THREAD(void)
{
    _endthreadex(0);
}

void    
_PR_MD_YIELD(void)
{
    /* Can NT really yield at all? */
    Sleep(0);
}

void     
_PR_MD_SET_PRIORITY(_MDThread *thread, PRThreadPriority newPri)
{