>From 9663d300d231242fc77f93a35219d56ba9c90601 Mon Sep 17 00:00:00 2001
From: Alan Third <address@hidden>
Date: Tue, 3 Jan 2017 14:16:37 +0000
Subject: [PATCH] Improve NS event handling (bug#25265)

* src/nsterm.h: Remove reference to timeout_handler.
* src/nsterm.m (ns_select): Monitor fd changes using NSFileHandler.
---
 src/nsterm.h |  1 -
 src/nsterm.m | 62 +++++++++++++++++++++++++++++++++++++++++++-----------------
 2 files changed, 45 insertions(+), 18 deletions(-)

diff --git a/src/nsterm.h b/src/nsterm.h
index dc222a7..8b5b691 100644
--- a/src/nsterm.h
+++ b/src/nsterm.h
@@ -392,7 +392,6 @@ char const * nstrace_fullscreen_type_name (int);
 - (void)sendEvent: (NSEvent *)theEvent;
 - (void)showPreferencesWindow: (id)sender;
 - (BOOL) openFile: (NSString *)fileName;
-- (void)timeout_handler: (NSTimer *)timedEntry;
 - (BOOL)fulfillService: (NSString *)name withArg: (NSString *)arg;
 #ifdef NS_IMPL_GNUSTEP
 - (void)sendFromMainThread:(id)unused;
diff --git a/src/nsterm.m b/src/nsterm.m
index 98fd8ab..51cccd0 100644
--- a/src/nsterm.m
+++ b/src/nsterm.m
@@ -4098,28 +4098,55 @@ overwriting cursor (usually when cursor on a tab) */
     return pselect(nfds, readfds, writefds,
                    exceptfds, timeout, sigmask);
 
-  result = pselect(nfds, readfds, writefds, exceptfds,
-                   &(struct timespec){.tv_sec = 0, .tv_nsec = 100},
-                   sigmask);
-
   [outerpool release];
   outerpool = [[NSAutoreleasePool alloc] init];
 
+  /* Set up one NSFileHandle for each fd we want to monitor. */
+  for (int i = 0 ; i < nfds ; i++)
+    {
+      if ((readfds != NULL && FD_ISSET(i, readfds))
+          || (writefds != NULL && FD_ISSET(i, writefds))
+          || (exceptfds != NULL &&FD_ISSET(i, exceptfds)))
+        {
+          NSFileHandle *fh = [[NSFileHandle alloc] initWithFileDescriptor: i
+                                                           closeOnDealloc: NO];
+          /* Send a notification to EmacsApp:fileHandleDataAvailable,
+             which will raise an appDefined event. */
+          /* NOTE: I don't think this will pick up writes and
+             exceptions, so ns_select may not always behave correctly.
+             I've yet to see a problem, though. */
+          [fh waitForDataInBackgroundAndNotify];
+          [fh autorelease];
+        }
+    }
+
   if (timeout)
     {
       double time = timespectod (*timeout);
-      timeout_date = [NSDate dateWithTimeIntervalSinceNow:time];
+      timeout_date = [NSDate dateWithTimeIntervalSinceNow: time];
     }
 
   /* Listen for a new NSEvent. */
-  ns_event = [NSApp nextEventMatchingMask:NSEventMaskAny
-                                untilDate:timeout_date
-                                   inMode:NSDefaultRunLoopMode
-                                  dequeue:NO];
+  ns_event = [NSApp nextEventMatchingMask: NSEventMaskAny
+                                untilDate: timeout_date
+                                   inMode: NSDefaultRunLoopMode
+                                  dequeue: NO];
 
   if (ns_event != nil)
     {
-      raise (SIGIO);
+      if ([ns_event type] == NSEventTypeApplicationDefined
+          && [ns_event data1] == -3)
+        {
+          result = pselect(nfds, readfds, writefds, exceptfds,
+                           &(struct timespec){.tv_sec = 0, .tv_nsec = 0},
+                           sigmask);
+        }
+      else
+        {
+          raise (SIGIO);
+          errno = EINTR;
+          return -1;
+        }
     }
 
   return result;
@@ -5132,6 +5159,12 @@ - (void)applicationDidFinishLaunching: (NSNotification *)notification
 	 object:nil];
 #endif
 
+  [[NSNotificationCenter defaultCenter]
+      addObserver: self
+         selector: @selector (fileHandleDataAvailable:)
+             name: NSFileHandleDataAvailableNotification
+           object: nil];
+
   ns_send_appdefined (-2);
 }
 
@@ -5315,14 +5348,9 @@ - (void)applicationDidResignActive: (NSNotification *)notification
 
    ========================================================================== */
 
-
-- (void)timeout_handler: (NSTimer *)timedEntry
-/* --------------------------------------------------------------------------
-     The timeout specified to ns_select has passed.
-   -------------------------------------------------------------------------- */
+- (void)fileHandleDataAvailable: (NSNotification *)notification
 {
-  /*NSTRACE ("timeout_handler"); */
-  ns_send_appdefined (-2);
+  ns_send_appdefined (-3);
 }
 
 - (void)sendFromMainThread:(id)unused
-- 
2.10.2