# HG changeset patch
# User Jens Alfke <jens@mooseyard.com>
# Date 1213917725 25200
# Node ID 3be241de163028d5f4718ffac9a8d584c4322dd7
# Parent  70590cc555aa1d50bede59b37f7146008e30a849
Implemented new close protocol with 'bye' meta-message.

diff -r 70590cc555aa -r 3be241de1630 BLIP/BLIPConnection.h
--- a/BLIP/BLIPConnection.h	Thu Jun 19 10:22:19 2008 -0700
+++ b/BLIP/BLIPConnection.h	Thu Jun 19 16:22:05 2008 -0700
@@ -20,6 +20,7 @@
 @interface BLIPConnection : TCPConnection
 {
     BLIPDispatcher *_dispatcher;
+    BOOL _blipClosing;
 }
 
 /** The delegate object that will be called when the connection opens, closes or receives messages. */
@@ -73,6 +74,13 @@
 /** Called when a BLIPResponse (to one of your requests) is received from the peer.
     This is called <i>after</i> the response object's onComplete target, if any, is invoked.*/
 - (void) connection: (BLIPConnection*)connection receivedResponse: (BLIPResponse*)response;
+
+/** Called when the peer wants to close the connection. Return YES to allow, NO to prevent. */
+- (BOOL) connectionReceivedCloseRequest: (BLIPConnection*)connection;
+
+/** Called if the peer refuses a close request. 
+    The typical error is BLIP error kBLIPError_Forbidden. */
+- (void) connection: (BLIPConnection*)connection closeRequestFailedWithError: (NSError*)error;
 @end
 
 
diff -r 70590cc555aa -r 3be241de1630 BLIP/BLIPConnection.m
--- a/BLIP/BLIPConnection.m	Thu Jun 19 10:22:19 2008 -0700
+++ b/BLIP/BLIPConnection.m	Thu Jun 19 16:22:05 2008 -0700
@@ -15,6 +15,7 @@
 #import "Logging.h"
 #import "Test.h"
 #import "ExceptionUtils.h"
+#import "Target.h"
 
 
 NSString* const BLIPErrorDomain = @"BLIP";
@@ -33,10 +34,14 @@
 }
 
 
+@interface BLIPConnection ()
+- (void) _handleCloseRequest: (BLIPRequest*)request;
+@end
 
 
 @implementation BLIPConnection
 
+
 - (void) dealloc
 {
     [_dispatcher release];
@@ -48,6 +53,11 @@
 - (id<BLIPConnectionDelegate>) delegate                     {return (id)_delegate;}
 - (void) setDelegate: (id<BLIPConnectionDelegate>)delegate  {_delegate = delegate;}
 
+
+#pragma mark -
+#pragma mark RECEIVING:
+
+
 - (BLIPDispatcher*) dispatcher
 {
     if( ! _dispatcher ) {
@@ -58,11 +68,23 @@
 }
 
 
+- (void) _dispatchMetaRequest: (BLIPRequest*)request
+{
+    NSString* profile = request.profile;
+    if( [profile isEqualToString: kBLIPProfile_Bye] )
+        [self _handleCloseRequest: request];
+    else
+        [request respondWithErrorCode: kBLIPError_NotFound message: @"Unknown meta profile"];
+}
+
+
 - (void) _dispatchRequest: (BLIPRequest*)request
 {
     LogTo(BLIP,@"Received all of %@",request.descriptionWithProperties);
     @try{
-        if( ! [self.dispatcher dispatchMessage: request] )
+        if( request._flags & kBLIP_Meta )
+            [self _dispatchMetaRequest: request];
+        else if( ! [self.dispatcher dispatchMessage: request] )
             [self tellDelegate: @selector(connection:receivedRequest:) withObject: request];
         if( ! request.noReply && ! request.repliedTo ) {
             LogTo(BLIP,@"Returning default empty response to %@",request);
@@ -81,6 +103,10 @@
 }
 
 
+#pragma mark -
+#pragma mark SENDING:
+
+
 - (BLIPRequest*) request
 {
     return [[[BLIPRequest alloc] _initWithConnection: self body: nil properties: nil] autorelease];
@@ -103,11 +129,61 @@
 }
 
 
+#pragma mark -
+#pragma mark CLOSING:
+
+
+- (void) _beginClose
+{
+    // Override of TCPConnection method. Instead of closing the socket, send a 'bye' request:
+    if( ! _blipClosing ) {
+        LogTo(BLIPVerbose,@"Sending close request...");
+        BLIPRequest *r = [self request];
+        [r _setFlag: kBLIP_Meta value: YES];
+        r.profile = kBLIPProfile_Bye;
+        BLIPResponse *response = [r send];
+        response.onComplete = $target(self,_receivedCloseResponse:);
+    }
+    // Put the writer in close mode, to prevent client from sending any more requests:
+    [self.writer close];
+}
+
+- (void) _receivedCloseResponse: (BLIPResponse*)response
+{
+    NSError *error = response.error;
+    LogTo(BLIPVerbose,@"Received close response: error=%@",error);
+    if( error ) {
+        if( [_delegate respondsToSelector: @selector(connection:closeRequestFailedWithError:)] )
+            [_delegate connection: self closeRequestFailedWithError: error];
+    } else {
+        // Now finally close the socket:
+        [super _beginClose];
+    }
+}
+
+
+- (void) _handleCloseRequest: (BLIPRequest*)request
+{
+    LogTo(BLIPVerbose,@"Received a close request");
+    if( [_delegate respondsToSelector: @selector(connectionReceivedCloseRequest:)] )
+        if( ! [_delegate connectionReceivedCloseRequest: self] ) {
+            LogTo(BLIPVerbose,@"Responding with denial of close request");
+            [request respondWithErrorCode: kBLIPError_Forbidden message: @"Close request denied"];
+            return;
+        }
+    
+    LogTo(BLIPVerbose,@"Close request accepted");
+    _blipClosing = YES; // this prevents _beginClose from sending a close request back
+    [self close];
+}
+
+
 @end
 
 
 
 
+#pragma mark -
 @implementation BLIPListener
 
 - (id) initWithPort: (UInt16)port
diff -r 70590cc555aa -r 3be241de1630 BLIP/BLIPMessage.m
--- a/BLIP/BLIPMessage.m	Thu Jun 19 10:22:19 2008 -0700
+++ b/BLIP/BLIPMessage.m	Thu Jun 19 16:22:05 2008 -0700
@@ -74,6 +74,8 @@
         [desc appendString: @", urgent"];
     if( _flags & kBLIP_NoReply )
         [desc appendString: @", noreply"];
+    if( _flags & kBLIP_Meta )
+        [desc appendString: @", META"];
     [desc appendString: @"]"];
     return desc;
 }
@@ -103,6 +105,8 @@
         _flags &= ~flag;
 }
 
+- (BLIPMessageFlags) _flags                 {return _flags;}
+
 - (BOOL) compressed                         {return (_flags & kBLIP_Compressed) != 0;}
 - (BOOL) urgent                             {return (_flags & kBLIP_Urgent) != 0;}
 - (void) setCompressed: (BOOL)compressed    {[self _setFlag: kBLIP_Compressed value: compressed];}
diff -r 70590cc555aa -r 3be241de1630 BLIP/BLIPReader.m
--- a/BLIP/BLIPReader.m	Thu Jun 19 10:22:19 2008 -0700
+++ b/BLIP/BLIPReader.m	Thu Jun 19 16:22:05 2008 -0700
@@ -93,7 +93,7 @@
 
 - (BOOL) isBusy
 {
-    return _curBytesRead > 0;
+    return _curBytesRead > 0 || _pendingRequests.count > 0 || _pendingResponses.count > 0;
 }
 
 
diff -r 70590cc555aa -r 3be241de1630 BLIP/BLIPRequest.m
--- a/BLIP/BLIPRequest.m	Thu Jun 19 10:22:19 2008 -0700
+++ b/BLIP/BLIPRequest.m	Thu Jun 19 16:22:05 2008 -0700
@@ -199,6 +199,8 @@
         setObj(&_mutableBody,nil);
         
         BLIPMutableProperties *errorProps = [self.properties mutableCopy];
+        if( ! errorProps )
+            errorProps = [[BLIPMutableProperties alloc] init];
         NSDictionary *userInfo = error.userInfo;
         for( NSString *key in userInfo ) {
             id value = $castIf(NSString,[userInfo objectForKey: key]);
@@ -227,8 +229,12 @@
 {
     Assert(_connection,@"%@ has no connection to send over",self);
     Assert(!_sent,@"%@ was already sent",self);
+    BLIPWriter *writer = (BLIPWriter*)_connection.writer;
+    Assert(writer,@"%@'s connection has no writer (already closed?)",self);
     [self _encode];
-    return (self.sent = [(BLIPWriter*)_connection.writer sendMessage: self]);
+    BOOL sent = self.sent = [writer sendMessage: self];
+    Assert(sent);
+    return sent;
 }
 
 
diff -r 70590cc555aa -r 3be241de1630 BLIP/BLIPTest.m
--- a/BLIP/BLIPTest.m	Thu Jun 19 10:22:19 2008 -0700
+++ b/BLIP/BLIPTest.m	Thu Jun 19 16:22:05 2008 -0700
@@ -35,6 +35,7 @@
 #define kClientUsesSSLCert          NO
 #define kListenerRequiresSSL        NO
 #define kListenerRequiresClientCert NO
+#define kListenerCloseAfter         50
 
 
 static SecIdentityRef GetClientIdentity(void) {
@@ -100,36 +101,38 @@
 
 - (void) sendAMessage
 {
-    if(_pending.count<100) {
-        Log(@"** Sending another %i messages...", kNBatchedMessages);
-        for( int i=0; i<kNBatchedMessages; i++ ) {
-            size_t size = random() % 32768;
-            NSMutableData *body = [NSMutableData dataWithLength: size];
-            UInt8 *bytes = body.mutableBytes;
-            for( size_t i=0; i<size; i++ )
-                bytes[i] = i % 256;
-            
-            BLIPRequest *q = [_conn requestWithBody: body
-                                         properties: $dict({@"Content-Type", @"application/octet-stream"},
-                                                           {@"User-Agent", @"BLIPConnectionTester"},
-                                                           {@"Date", [[NSDate date] description]},
-                                                           {@"Size",$sprintf(@"%u",size)})];
-            Assert(q);
-            if( kUseCompression && (random()%2==1) )
-                q.compressed = YES;
-            if( random()%16 > 12 )
-                q.urgent = YES;
-            BLIPResponse *response = [q send];
-            Assert(response);
-            Assert(q.number>0);
-            Assert(response.number==q.number);
-            [_pending setObject: $object(size) forKey: $object(q.number)];
-            response.onComplete = $target(self,responseArrived:);
+    if( _conn.status==kTCP_Open || _conn.status==kTCP_Opening ) {
+        if(_pending.count<100) {
+            Log(@"** Sending another %i messages...", kNBatchedMessages);
+            for( int i=0; i<kNBatchedMessages; i++ ) {
+                size_t size = random() % 32768;
+                NSMutableData *body = [NSMutableData dataWithLength: size];
+                UInt8 *bytes = body.mutableBytes;
+                for( size_t i=0; i<size; i++ )
+                    bytes[i] = i % 256;
+                
+                BLIPRequest *q = [_conn requestWithBody: body
+                                             properties: $dict({@"Content-Type", @"application/octet-stream"},
+                                                               {@"User-Agent", @"BLIPConnectionTester"},
+                                                               {@"Date", [[NSDate date] description]},
+                                                               {@"Size",$sprintf(@"%u",size)})];
+                Assert(q);
+                if( kUseCompression && (random()%2==1) )
+                    q.compressed = YES;
+                if( random()%16 > 12 )
+                    q.urgent = YES;
+                BLIPResponse *response = [q send];
+                Assert(response);
+                Assert(q.number>0);
+                Assert(response.number==q.number);
+                [_pending setObject: $object(size) forKey: $object(q.number)];
+                response.onComplete = $target(self,responseArrived:);
+            }
+        } else {
+            Warn(@"There are %u pending messages; waiting for the listener to catch up...",_pending.count);
         }
-    } else {
-        Warn(@"There are %u pending messages; waiting for the listener to catch up...",_pending.count);
+        [self performSelector: @selector(sendAMessage) withObject: nil afterDelay: kSendInterval];
     }
-    [self performSelector: @selector(sendAMessage) withObject: nil afterDelay: kSendInterval];
 }
 
 - (void) responseArrived: (BLIPResponse*)response
@@ -217,6 +220,7 @@
 @interface BLIPTestListener : NSObject <TCPListenerDelegate, BLIPConnectionDelegate>
 {
     BLIPListener *_listener;
+    int _nReceived;
 }
 
 @end
@@ -277,6 +281,7 @@
 - (void) connectionDidOpen: (TCPConnection*)connection
 {
     Log(@"** %@ didOpen [SSL=%@]",connection,connection.actualSecurityLevel);
+    _nReceived = 0;
 }
 - (BOOL) connection: (TCPConnection*)connection authorizeSSLPeer: (SecCertificateRef)peerCert
 {
@@ -312,6 +317,11 @@
     AssertEq([[request valueOfProperty: @"Size"] intValue], size);
 
     [request respondWithData: body contentType: request.contentType];
+    
+    if( ++ _nReceived == kListenerCloseAfter ) {
+        Log(@"********** Closing BLIPTestListener after %i requests",_nReceived);
+        [connection close];
+    }
 }
 
 
diff -r 70590cc555aa -r 3be241de1630 BLIP/BLIPWriter.m
--- a/BLIP/BLIPWriter.m	Thu Jun 19 10:22:19 2008 -0700
+++ b/BLIP/BLIPWriter.m	Thu Jun 19 16:22:05 2008 -0700
@@ -79,10 +79,6 @@
 
 - (BOOL) sendMessage: (BLIPMessage*)message
 {
-    if( _shouldClose ) {
-        Warn(@"%@: Attempt to send a message after the connection has started closing",self);
-        return NO;
-    }
     Assert(!message.sent,@"message has already been sent");
     [self _queueMessage: message isNew: YES];
     return YES;
@@ -91,12 +87,14 @@
 
 - (BOOL) sendRequest: (BLIPRequest*)q response: (BLIPResponse*)response
 {
-    if( !_shouldClose ) {
-        [q _assignedNumber: ++_numRequestsSent];
-        if( response ) {
-            [response _assignedNumber: _numRequestsSent];
-            [(BLIPReader*)self.reader _addPendingResponse: response];
-        }
+    if( _shouldClose ) {
+        Warn(@"%@: Attempt to send a request after the connection has started closing: %@",self,q);
+        return NO;
+    }
+    [q _assignedNumber: ++_numRequestsSent];
+    if( response ) {
+        [response _assignedNumber: _numRequestsSent];
+        [(BLIPReader*)self.reader _addPendingResponse: response];
     }
     return [self sendMessage: q];
 }
diff -r 70590cc555aa -r 3be241de1630 BLIP/BLIP_Internal.h
--- a/BLIP/BLIP_Internal.h	Thu Jun 19 10:22:19 2008 -0700
+++ b/BLIP/BLIP_Internal.h	Thu Jun 19 16:22:05 2008 -0700
@@ -29,6 +29,7 @@
     kBLIP_Urgent    = 0x0020,       // please send sooner/faster
     kBLIP_NoReply   = 0x0040,       // no RPY needed
     kBLIP_MoreComing= 0x0080,       // More frames coming (Applies only to individual frame)
+    kBLIP_Meta      = 0x0100,       // Special message type, handled internally (hello, bye, ...)
 };
 typedef UInt16 BLIPMessageFlags;
 
@@ -43,6 +44,9 @@
 
 #define kBLIPFrameHeaderMagicNumber 0x9B34F205
 
+#define kBLIPProfile_Hi  @"Hi"      // Used for Profile header in meta greeting message
+#define kBLIPProfile_Bye @"Bye"     // Used for Profile header in meta close-request message
+
 
 @interface BLIPConnection ()
 - (void) _dispatchRequest: (BLIPRequest*)request;
@@ -52,6 +56,7 @@
 
 @interface BLIPMessage ()
 @property BOOL sent, propertiesAvailable, complete;
+- (BLIPMessageFlags) _flags;
 - (void) _setFlag: (BLIPMessageFlags)flag value: (BOOL)value;
 - (void) _encode;
 @end
diff -r 70590cc555aa -r 3be241de1630 TCP/TCPConnection.h
--- a/TCP/TCPConnection.h	Thu Jun 19 10:22:19 2008 -0700
+++ b/TCP/TCPConnection.h	Thu Jun 19 16:22:05 2008 -0700
@@ -108,6 +108,7 @@
 // protected:
 - (Class) readerClass;
 - (Class) writerClass;
+- (void) _beginClose;
 
 @end
 
diff -r 70590cc555aa -r 3be241de1630 TCP/TCPConnection.m
--- a/TCP/TCPConnection.m	Thu Jun 19 10:22:19 2008 -0700
+++ b/TCP/TCPConnection.m	Thu Jun 19 16:22:05 2008 -0700
@@ -207,9 +207,7 @@
     if( _status > kTCP_Closed ) {
         LogTo(TCP,@"%@ disconnecting",self);
         [_writer disconnect];
-        setObj(&_writer,nil);
         [_reader disconnect];
-        setObj(&_reader,nil);
         self.status = kTCP_Disconnected;
     }
     [self _stopOpenTimer];
@@ -231,8 +229,7 @@
         LogTo(TCP,@"%@ closing",self);
         self.status = kTCP_Closing;
         [self retain];
-        [_reader close];
-        [_writer close];
+        [self _beginClose];
         if( ! [self _checkIfClosed] ) {
             if( timeout <= 0.0 )
                 [self disconnect];
@@ -251,6 +248,13 @@
 }
 
 
+- (void) _beginClose
+{
+    [_reader close];
+    [_writer close];
+}
+
+
 - (BOOL) _checkIfClosed
 {
     if( _status == kTCP_Closing && _writer==nil && _reader==nil ) {
@@ -356,27 +360,16 @@
     [[self retain] autorelease];
     setObj(&_error,error);
     [_reader disconnect];
-    setObj(&_reader,nil);
     [_writer disconnect];
-    setObj(&_writer,nil);
     [self _closed];
 }
 
 - (void) _streamGotEOF: (TCPStream*)stream
 {
     LogTo(TCP,@"%@ got EOF on %@",self,stream);
-    if( stream == _reader ) {
-        setObj(&_reader,nil);
-        // This is the expected way for he peer to initiate closing the connection.
-        if( _status==kTCP_Open ) {
-            [self closeWithTimeout: INFINITY];
-            return;
-        }
-    } else if( stream == _writer ) {
-        setObj(&_writer,nil);
-    }
-    
+    [stream disconnect];
     if( _status == kTCP_Closing ) {
+        [self _streamCanClose: stream];
         [self _checkIfClosed];
     } else {
         [self _stream: stream 
@@ -385,14 +378,27 @@
 }
 
 
+// Called as soon as a stream is ready to close, after its -close method has been called.
+- (void) _streamCanClose: (TCPStream*)stream
+{
+    if( ! _reader.isActive && !_writer.isActive ) {
+        LogTo(TCPVerbose,@"Both streams are ready to close now!");
+        [_reader disconnect];
+        [_writer disconnect];
+    }
+}
+
+
 // Called after I called -close on a stream and it finished closing:
-- (void) _streamClosed: (TCPStream*)stream
+- (void) _streamDisconnected: (TCPStream*)stream
 {
-    LogTo(TCP,@"%@ finished closing %@",self,stream);
+    LogTo(TCP,@"%@: disconnected %@",self,stream);
     if( stream == _reader )
         setObj(&_reader,nil);
     else if( stream == _writer )
         setObj(&_writer,nil);
+    else
+        return;
     if( !_reader.isOpen && !_writer.isOpen )
         [self _closed];
 }
diff -r 70590cc555aa -r 3be241de1630 TCP/TCPStream.h
--- a/TCP/TCPStream.h	Thu Jun 19 10:22:19 2008 -0700
+++ b/TCP/TCPStream.h	Thu Jun 19 16:22:05 2008 -0700
@@ -47,6 +47,9 @@
 /** Does the stream have pending data to read or write, that prevents it from closing? */
 @property (readonly) BOOL isBusy;
 
+/** Returns NO if the stream is ready to close (-close has been called and -isBusy is NO.) */
+@property (readonly) BOOL isActive;
+
 /** Generic accessor for CFStream/NSStream properties. */
 - (id) propertyForKey: (CFStringRef)cfStreamProperty;
 
diff -r 70590cc555aa -r 3be241de1630 TCP/TCPStream.m
--- a/TCP/TCPStream.m	Thu Jun 19 10:22:19 2008 -0700
+++ b/TCP/TCPStream.m	Thu Jun 19 16:22:05 2008 -0700
@@ -110,20 +110,24 @@
         [_stream close];
         setObj(&_stream,nil);
     }
-    setObj(&_conn,nil);
+    if( _conn ) {
+        [self retain];
+        [_conn _streamDisconnected: self];
+        setObj(&_conn,nil);
+        [self release];
+    }
 }
 
 
 - (BOOL) close
 {
+    _shouldClose = YES;
     if( self.isBusy ) {
-        _shouldClose = YES;
         return NO;
     } else {
-        LogTo(TCP,@"Closing %@",self);
-        [[self retain] autorelease];    // don't let myself be dealloced in the midst of this
-        [_conn _streamClosed: self];    // have to do this before disconnect
-        [self disconnect];
+        LogTo(TCP,@"Request to close %@",self);
+        [[self retain] autorelease];        // don't let myself be dealloced in the midst of this
+        [_conn _streamCanClose: self];
         return YES;
     }
 }
@@ -140,6 +144,11 @@
     return NO;  // abstract
 }
 
+- (BOOL) isActive
+{
+    return !_shouldClose || self.isBusy;
+}
+
 
 - (void) _opened
 {
@@ -158,14 +167,7 @@
 
 - (void) _gotEOF
 {
-    if( self.isBusy )
-        [self _gotError: [NSError errorWithDomain: NSPOSIXErrorDomain code: ECONNRESET userInfo: nil]];
-    else {
-        [self retain];
-        [_conn _streamGotEOF: self];
-        [self disconnect];
-        [self release];
-    }
+    [_conn _streamGotEOF: self];
 }
 
 - (BOOL) _gotError: (NSError*)error
diff -r 70590cc555aa -r 3be241de1630 TCP/TCP_Internal.h
--- a/TCP/TCP_Internal.h	Thu Jun 19 10:22:19 2008 -0700
+++ b/TCP/TCP_Internal.h	Thu Jun 19 16:22:05 2008 -0700
@@ -20,6 +20,7 @@
 - (void) _streamOpened: (TCPStream*)stream;
 - (BOOL) _streamPeerCertAvailable: (TCPStream*)stream;
 - (void) _stream: (TCPStream*)stream gotError: (NSError*)error;
+- (void) _streamCanClose: (TCPStream*)stream;
 - (void) _streamGotEOF: (TCPStream*)stream;
-- (void) _streamClosed: (TCPStream*)stream;
+- (void) _streamDisconnected: (TCPStream*)stream;
 @end