--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nspr/pr/src/io/prpolevt.c	Mon Jul 28 10:47:06 2014 +0200
@@ -0,0 +1,230 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ *********************************************************************
+ *
+ * Pollable events
+ *
+ * Pollable events are implemented using layered I/O.  The only
+ * I/O methods that are implemented for pollable events are poll
+ * and close.  No other methods can be invoked on a pollable
+ * event.
+ *
+ * A pipe or socket pair is created and the pollable event layer
+ * is pushed onto the read end.  A pointer to the write end is
+ * saved in the PRFilePrivate structure of the pollable event.
+ *
+ *********************************************************************
+ */
+
+#include "prinit.h"
+#include "prio.h"
+#include "prmem.h"
+#include "prerror.h"
+#include "prlog.h"
+
+/*
+ * These internal functions are declared in primpl.h,
+ * but we can't include primpl.h because the definition
+ * of struct PRFilePrivate in this file (for the pollable
+ * event layer) will conflict with the definition of
+ * struct PRFilePrivate in primpl.h (for the NSPR layer).
+ */
+extern PRIntn _PR_InvalidInt(void);
+extern PRInt64 _PR_InvalidInt64(void);
+extern PRStatus _PR_InvalidStatus(void);
+extern PRFileDesc *_PR_InvalidDesc(void);
+
+/*
+ * PRFilePrivate structure for the NSPR pollable events layer
+ */
+struct PRFilePrivate {
+    PRFileDesc *writeEnd;  /* the write end of the pipe/socketpair */
+};
+
+static PRStatus PR_CALLBACK _pr_PolEvtClose(PRFileDesc *fd);
+
+static PRInt16 PR_CALLBACK _pr_PolEvtPoll(
+    PRFileDesc *fd, PRInt16 in_flags, PRInt16 *out_flags);
+
+static PRIOMethods _pr_polevt_methods = {
+    PR_DESC_LAYERED,
+    _pr_PolEvtClose,
+    (PRReadFN)_PR_InvalidInt,
+    (PRWriteFN)_PR_InvalidInt,
+    (PRAvailableFN)_PR_InvalidInt,
+    (PRAvailable64FN)_PR_InvalidInt64,
+    (PRFsyncFN)_PR_InvalidStatus,
+    (PRSeekFN)_PR_InvalidInt,
+    (PRSeek64FN)_PR_InvalidInt64,
+    (PRFileInfoFN)_PR_InvalidStatus,
+    (PRFileInfo64FN)_PR_InvalidStatus,
+    (PRWritevFN)_PR_InvalidInt,        
+    (PRConnectFN)_PR_InvalidStatus,        
+    (PRAcceptFN)_PR_InvalidDesc,        
+    (PRBindFN)_PR_InvalidStatus,        
+    (PRListenFN)_PR_InvalidStatus,        
+    (PRShutdownFN)_PR_InvalidStatus,    
+    (PRRecvFN)_PR_InvalidInt,        
+    (PRSendFN)_PR_InvalidInt,        
+    (PRRecvfromFN)_PR_InvalidInt,    
+    (PRSendtoFN)_PR_InvalidInt,        
+    _pr_PolEvtPoll,
+    (PRAcceptreadFN)_PR_InvalidInt,   
+    (PRTransmitfileFN)_PR_InvalidInt, 
+    (PRGetsocknameFN)_PR_InvalidStatus,    
+    (PRGetpeernameFN)_PR_InvalidStatus,    
+    (PRReservedFN)_PR_InvalidInt,    
+    (PRReservedFN)_PR_InvalidInt,    
+    (PRGetsocketoptionFN)_PR_InvalidStatus,
+    (PRSetsocketoptionFN)_PR_InvalidStatus,
+    (PRSendfileFN)_PR_InvalidInt, 
+    (PRConnectcontinueFN)_PR_InvalidStatus, 
+    (PRReservedFN)_PR_InvalidInt, 
+    (PRReservedFN)_PR_InvalidInt, 
+    (PRReservedFN)_PR_InvalidInt, 
+    (PRReservedFN)_PR_InvalidInt
+};
+
+static PRDescIdentity _pr_polevt_id;
+static PRCallOnceType _pr_polevt_once_control;
+static PRStatus PR_CALLBACK _pr_PolEvtInit(void);
+
+static PRInt16 PR_CALLBACK _pr_PolEvtPoll(
+    PRFileDesc *fd, PRInt16 in_flags, PRInt16 *out_flags)
+{
+    return (fd->lower->methods->poll)(fd->lower, in_flags, out_flags);
+}
+
+static PRStatus PR_CALLBACK _pr_PolEvtInit(void)
+{
+    _pr_polevt_id = PR_GetUniqueIdentity("NSPR pollable events");
+    if (PR_INVALID_IO_LAYER == _pr_polevt_id) {
+        return PR_FAILURE;
+    }
+    return PR_SUCCESS;
+}
+
+#if !defined(XP_UNIX)
+#define USE_TCP_SOCKETPAIR
+#endif
+
+PR_IMPLEMENT(PRFileDesc *) PR_NewPollableEvent(void)
+{
+    PRFileDesc *event;
+    PRFileDesc *fd[2]; /* fd[0] is the read end; fd[1] is the write end */
+#ifdef USE_TCP_SOCKETPAIR
+    PRSocketOptionData socket_opt;
+    PRStatus rv;
+#endif
+
+    fd[0] = fd[1] = NULL;
+
+    if (PR_CallOnce(&_pr_polevt_once_control, _pr_PolEvtInit) == PR_FAILURE) {
+        return NULL;
+    }
+
+    event = PR_CreateIOLayerStub(_pr_polevt_id, &_pr_polevt_methods);
+    if (NULL == event) {
+        goto errorExit;
+    } 
+    event->secret = PR_NEW(PRFilePrivate);
+    if (event->secret == NULL) {
+        PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
+        goto errorExit;
+    }
+
+#ifndef USE_TCP_SOCKETPAIR
+    if (PR_CreatePipe(&fd[0], &fd[1]) == PR_FAILURE) {
+        fd[0] = fd[1] = NULL;
+        goto errorExit;
+    }
+#else
+    if (PR_NewTCPSocketPair(fd) == PR_FAILURE) {
+        fd[0] = fd[1] = NULL;
+        goto errorExit;
+    }
+	/*
+	 * set the TCP_NODELAY option to reduce notification latency
+	 */
+    socket_opt.option = PR_SockOpt_NoDelay;
+    socket_opt.value.no_delay = PR_TRUE;
+    rv = PR_SetSocketOption(fd[1], &socket_opt);
+    PR_ASSERT(PR_SUCCESS == rv);
+#endif
+
+    event->secret->writeEnd = fd[1];
+    if (PR_PushIOLayer(fd[0], PR_TOP_IO_LAYER, event) == PR_FAILURE) {
+        goto errorExit;
+    }
+
+    return fd[0];
+
+errorExit:
+    if (fd[0]) {
+        PR_Close(fd[0]);
+        PR_Close(fd[1]);
+    }
+    if (event) {
+        PR_DELETE(event->secret);
+        event->dtor(event);
+    }
+    return NULL;
+}
+
+static PRStatus PR_CALLBACK _pr_PolEvtClose(PRFileDesc *fd)
+{
+    PRFileDesc *event;
+
+    event = PR_PopIOLayer(fd, PR_TOP_IO_LAYER);
+    PR_ASSERT(NULL == event->higher && NULL == event->lower);
+    PR_Close(fd);
+    PR_Close(event->secret->writeEnd);
+    PR_DELETE(event->secret);
+    event->dtor(event);
+    return PR_SUCCESS;
+}
+
+PR_IMPLEMENT(PRStatus) PR_DestroyPollableEvent(PRFileDesc *event)
+{
+    return PR_Close(event);
+}
+
+static const char magicChar = '\x38';
+
+PR_IMPLEMENT(PRStatus) PR_SetPollableEvent(PRFileDesc *event)
+{
+    if (PR_Write(event->secret->writeEnd, &magicChar, 1) != 1) {
+        return PR_FAILURE;
+    }
+    return PR_SUCCESS;
+}
+
+PR_IMPLEMENT(PRStatus) PR_WaitForPollableEvent(PRFileDesc *event)
+{
+    char buf[1024];
+    PRInt32 nBytes;
+#ifdef DEBUG
+    PRIntn i;
+#endif
+
+    nBytes = PR_Read(event->lower, buf, sizeof(buf));
+    if (nBytes == -1) {
+        return PR_FAILURE;
+    }
+
+#ifdef DEBUG
+    /*
+     * Make sure people do not write to the pollable event fd
+     * directly.
+     */
+    for (i = 0; i < nBytes; i++) {
+        PR_ASSERT(buf[i] == magicChar);
+    }
+#endif
+
+    return PR_SUCCESS;
+}