Fixes for I/O operations which complete synchronously even though we wanted

them to be asynchronous.


git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@21988 72102866-910b-0410-8b05-ffd578937521

Source/win32/GSRunLoopCtxt.m

@@ -429,6 +429,7 @@ static const NSMapTableValueCallBacks WatcherMapValueCallBacks =
        * The watcher is still valid - so call its receivers
        * event handling method.
        */
+      NSDebugMLLog(@"NSRunLoop", @"Event callback found");
       (*watcher->handleEvent)(watcher->receiver,
           eventSel, watcher->data, watcher->type,
           (void*)(gsaddr)handle, mode);

Source/win32/NSMessagePortWin32.m

@@ -96,6 +96,13 @@ typedef struct {
   unsigned char	port[16];
 } GSPortMsgHeader;
 
+typedef enum {
+  RS_NONE,	// Not started yet
+  RS_MESG,	// Waiting to be notified of a message arriving
+  RS_SIZE,	// Need to determine message size
+  RS_DATA	// Need to read message data
+} ReadState;
+
 typedef	struct {
   NSString              *name;
   NSRecursiveLock       *lock;
@@ -103,6 +110,7 @@ typedef	struct {
   HANDLE                wHandle;
   HANDLE                rEvent;
   HANDLE                wEvent;
+  ReadState		rState;
   OVERLAPPED		rOv;
   OVERLAPPED		wOv;
   DWORD			rSize;
@@ -309,6 +317,7 @@ static unsigned	wordAlign;
   this->wHandle = INVALID_HANDLE_VALUE;
   this->wEvent = INVALID_HANDLE_VALUE;
 
+  this->rState = RS_NONE;
   this->rEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
   this->rData = [NSMutableData new];
   this->rMsgs = [NSMutableArray new];
@@ -367,6 +376,8 @@ static unsigned	wordAlign;
 
       this->lock = [GSLazyRecursiveLock new];
 
+      this->rState = RS_NONE;
+
       this->rHandle = INVALID_HANDLE_VALUE;
       this->rEvent = INVALID_HANDLE_VALUE;
       this->wHandle = INVALID_HANDLE_VALUE;
@@ -476,7 +487,9 @@ static unsigned	wordAlign;
 
   M_LOCK(this->lock);
 
-  if (this->rWant > 0)
+  NSDebugMLLog(@"NSMessagePort", @"entered with rWant=%d", this->rWant);
+
+  if (this->rState == RS_MESG)
     {
       /*
        * Have we read something?
@@ -488,6 +501,7 @@ static unsigned	wordAlign;
 	TRUE) == 0)
 	{
 	  errno = GetLastError();
+	  NSDebugMLLog(@"NSMessagePort", @"overlapped result=%d", errno);
 	  /*
 	   * Our overlapped read attempt should fail ... because mailslots
 	   * insist we read an entire message in one go, and we asked it
@@ -497,6 +511,25 @@ static unsigned	wordAlign;
 	   * synchronously.
 	   */
 	  if (errno == ERROR_INSUFFICIENT_BUFFER)
+	    {
+	      this->rState = RS_SIZE;
+	    }
+	  else
+	    {
+	      NSLog(@"GetOverlappedResult failed ...%s", GSLastErrorStr(errno));
+	      this->rState = RS_NONE;
+	      this->rLength = 0;
+	    }
+	}
+      else
+	{
+	  NSLog(@"GetOverlappedResult success ...%u", this->rSize);
+	  this->rState = RS_NONE;
+	  this->rLength = 0;
+	}
+    }
+
+  if (this->rState == RS_SIZE)
     {
       if (GetMailslotInfo(
 	this->rHandle,
@@ -512,6 +545,9 @@ static unsigned	wordAlign;
 	}
       else
 	{
+	  this->rState = RS_DATA;
+	  NSDebugMLLog(@"NSMessagePort", @"mailslot size=%d",
+	    this->rWant);
 	  [this->rData setLength: this->rWant];
 	  if (ReadFile(this->rHandle,
 	    [this->rData mutableBytes],	// Store results here
@@ -539,26 +575,14 @@ static unsigned	wordAlign;
 	    }
 	  this->rLength = this->rSize;
 	  this->rSize = 0;
+	  this->rState = RS_NONE;
 	}
     }
-	  else
-	    {
-	      NSLog(@"GetOverlappedResult failed ...%s", GSLastErrorStr(errno));
-	      this->rLength = 0;
-	      this->rWant = 1;
-	    }
-	}
-      else
-	{
-	  NSLog(@"GetOverlappedResult succes ...%u", this->rSize);
-	  this->rLength += this->rSize;
-	  this->rSize = 0;
-	}
 
   /*
    * Do next part only if we have completed a read.
    */
-      if (this->rLength == this->rWant)
+  if (this->rLength > 0 && this->rLength == this->rWant)
     {
       unsigned char	*buf = [this->rData mutableBytes];
       GSPortItemType	rType;
@@ -678,30 +702,24 @@ static unsigned	wordAlign;
 	}
       DESTROY(rPort);
       DESTROY(rItems);
-	  this->rWant = 1;		// Queue a read
-	  this->rLength = 0;
-	}
-      else
-	{
-	  NSLog(@"Unexpected STATE");
-	}
-    }
-  else
-    {
-      this->rWant = 1;		// Queue a read
-      this->rLength = 0;
     }
 
   /*
    * Got something ... is it all we want? If not, ask to read more.
    */
-  if ([self isValid] == YES && this->rLength < this->rWant)
+  if ([self isValid] == YES
+    && (this->rState == RS_NONE || this->rLength < this->rWant))
     {
       int	rc;
 
       this->rOv.Offset = 0;
       this->rOv.OffsetHigh = 0;
       this->rOv.hEvent = this->rEvent;
+      if (this->rState == RS_NONE)
+	{
+	  this->rLength = 0;
+	  this->rWant = 1;
+	}
       if ([this->rData length] < (this->rWant - this->rLength))
 	{
 	  [this->rData setLength: this->rWant - this->rLength];
@@ -715,15 +733,27 @@ static unsigned	wordAlign;
       if (rc > 0)
 	{
 	  NSDebugMLLog(@"NSMessagePort", @"Read immediate on %@", self);
+	  if (this->rState == RS_NONE)
+	    {
+	      this->rState = RS_SIZE;
+	    }
 	  SetEvent(this->rEvent);
 	}
       else if ((errno = GetLastError()) == ERROR_IO_PENDING)
 	{
 	  NSDebugMLLog(@"NSMessagePort", @"Read queued on %@", self);
+	  if (this->rState == RS_NONE)
+	    {
+	      this->rState = RS_MESG;
+	    }
 	}
       else if (errno == ERROR_INSUFFICIENT_BUFFER)
 	{
 	  NSDebugMLLog(@"NSMessagePort", @"Read retry on %@", self);
+	  if (this->rState == RS_NONE)
+	    {
+	      this->rState = RS_SIZE;
+	    }
 	  SetEvent(this->rEvent);
 	}
       else
@@ -792,6 +822,8 @@ static unsigned	wordAlign;
 	}
     }
 
+again:
+
   /*
    * Handle start of next data item if we have completed one,
    * or if we are called without a write in progress.
@@ -828,7 +860,8 @@ static unsigned	wordAlign;
 	{
 	  NSDebugMLLog(@"NSMessagePort", @"Write of %d performs %d",
 	    [this->wData length] - this->wLength, this->wSize);
-	  SetEvent(this->wEvent);
+	  this->wLength += this->wSize;
+	  goto again;
 	}
       else if ((errno = GetLastError()) != ERROR_IO_PENDING)
 	{
@@ -855,6 +888,7 @@ static unsigned	wordAlign;
     {
       internal	*this = PORT(self);
 
+      NSDebugMLLog(@"NSMessagePort", @"got event on %@ in mode %@", self, mode);
       if (this->rEvent == (HANDLE)data)
 	{
 	  [self receivedEventRead];
@@ -866,7 +900,8 @@ static unsigned	wordAlign;
     }
   else
     {
-      // Event on invalid port ... remove port from run loop
+      NSDebugMLLog(@"NSMessagePort",
+	@"got event on invalidated port 0x%x in mode %@", self, mode);
       [[NSRunLoop currentRunLoop] removeEvent: data
 					 type: type
 				      forMode: mode