From 9d75a88d3f275d10f0c17be4484db6a5ba6e1c9b Mon Sep 17 00:00:00 2001
From: Kevin McCarthy <kevin@8t8.us>
Date: Tue, 5 Jun 2018 17:38:44 -0700
Subject: [PATCH] Quick fix for ncurses buffering issue with inotify polling.

Ncurses does its own buffering for some character sequences, notable
Esc-prefixed input.  Add a non-blocking check for getch() before
performing the mutt_monitor_poll() call.

This is a quick fix, which I'll clean up more later.
---
 curs_lib.c | 28 +++++++++++++++++++++++-----
 monitor.c  |  5 +++++
 monitor.h  |  1 +
 3 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/curs_lib.c b/curs_lib.c
index 63ab60f38..f1c0943e7 100644
--- a/curs_lib.c
+++ b/curs_lib.c
@@ -132,6 +132,25 @@ void mutt_getch_timeout(int delay)
 #endif
 }
 
+#ifdef USE_INOTIFY
+static int mutt_monitor_getch(void)
+{
+  /* ncurses has its own internal buffer, so before we perform a poll,
+   * we need to make sure there isn't a character waiting */
+  timeout(0);
+  int ch = getch();
+  timeout(mutt_monitor_get_poll_timeout());
+  if (ch == ERR)
+  {
+    if (mutt_monitor_poll() != 0)
+      ch = ERR;
+    else
+      ch = getch();
+  }
+  return ch;
+}
+#endif /* USE_INOTIFY */
+
 /**
  * mutt_getch - Read a character from the input buffer
  * @retval obj Event to process
@@ -166,11 +185,10 @@ struct Event mutt_getch(void)
   while (ch == KEY_RESIZE)
 #endif /* KEY_RESIZE */
 #ifdef USE_INOTIFY
-    if (mutt_monitor_poll() != 0)
-      ch = ERR;
-    else
-#endif
-      ch = getch();
+    ch = mutt_monitor_getch();
+#else
+  ch = getch();
+#endif /* USE_INOTIFY */
   mutt_sig_allow_interrupt(0);
 
   if (SigInt)
diff --git a/monitor.c b/monitor.c
index 30019cd6b..2e9d3c67b 100644
--- a/monitor.c
+++ b/monitor.c
@@ -219,6 +219,11 @@ void mutt_monitor_set_poll_timeout(int timeout)
   PollTimeout = timeout;
 }
 
+int mutt_monitor_get_poll_timeout(void)
+{
+  return PollTimeout;
+}
+
 #define EVENT_BUFLEN MAX(4096, sizeof(struct inotify_event) + NAME_MAX + 1)
 
 /* mutt_monitor_poll: Waits for I/O ready file descriptors or signals.
diff --git a/monitor.h b/monitor.h
index d61550b05..4d76ca001 100644
--- a/monitor.h
+++ b/monitor.h
@@ -30,6 +30,7 @@ struct Mailbox;
 int mutt_monitor_add(struct Mailbox *b);
 int mutt_monitor_remove(struct Mailbox *b);
 void mutt_monitor_set_poll_timeout(int timeout);
+int mutt_monitor_get_poll_timeout(void);
 int mutt_monitor_poll(void);
 
 #endif /* _MUTT_MONITOR_H */
-- 
2.50.1