From e706fca4d6e364aa520ca7bab06ca2ef0aa04447 Mon Sep 17 00:00:00 2001
From: Bjorn Winckler <bjorn.winckler@gmail.com>
Date: Sat, 10 Jan 2009 17:38:11 +0100
Subject: [PATCH] Cmd-. sends SIGINT

Ctrl-C does not always work to interrupt a stuck Vim process. By making
Cmd-. send SIGINT it is more likely to succeed where Ctrl-C has failed.
(E.g. Ctrl-C may fail if a DO message is dropped, or if the Vim process
is stuck in a loop and isn't checking for new input.)
---
 runtime/doc/gui_mac.txt       | 10 ++++++----
 src/MacVim/MMBackend.m        | 14 +++-----------
 src/MacVim/MMTextViewHelper.m |  8 ++++++--
 src/MacVim/MacVim.h           |  1 -
 src/MacVim/MacVim.m           |  1 -
 src/MacVim/gui_macvim.m       |  3 ++-
 6 files changed, 17 insertions(+), 20 deletions(-)

diff --git a/runtime/doc/gui_mac.txt b/runtime/doc/gui_mac.txt
index d7b3553598..00cf919e5d 100644
--- a/runtime/doc/gui_mac.txt
+++ b/runtime/doc/gui_mac.txt
@@ -1,4 +1,4 @@
-*gui_mac.txt*	For Vim version 7.2.  Last change: 2009 Jan 07
+*gui_mac.txt*	For Vim version 7.2.  Last change: 2009 Jan 08
 
 
 		  VIM REFERENCE MANUAL    by Bjorn Winckler
@@ -563,9 +563,11 @@ discovered by looking through the menus (see |macvim-menus| on how to create
 your own menu shortcuts).  The remaining shortcuts are listed here:
 
 							*Cmd-.* *<D-.>*
-Cmd-.			Interrupt Vim.  This is synonymous with CTRL-C and can
-			hence be used instead of Esc to exit insert mode (in
-			case you find Esc a bit hard to reach).
+Cmd-.			Interrupt Vim.  Unlike Ctrl-C which is sent as normal
+			keyboard input (and hence has to be received and then
+			interpreted) this sends a SIGINT signal to the Vim
+			process.  Use this shortcut if the Vim process appears
+			to have locked up and is not responding to key presses.
 
 							*Cmd-`* *<D-`>*
 Cmd-`			Cycle to the next window.  On an American keyboard the
diff --git a/src/MacVim/MMBackend.m b/src/MacVim/MMBackend.m
index 44d27ff78d..5316c9ad88 100644
--- a/src/MacVim/MMBackend.m
+++ b/src/MacVim/MMBackend.m
@@ -1037,11 +1037,7 @@ extern GuiFont gui_mch_retain_font(GuiFont font);
     // which waits on the run loop will fail to detect this message (e.g. in
     // waitForConnectionAcknowledgement).
 
-    BOOL shouldClearQueue = NO;
-    if (InterruptMsgID == msgid) {
-        shouldClearQueue = YES;
-        got_int = TRUE;
-    } else if (InsertTextMsgID == msgid && data != nil) {
+    if (InsertTextMsgID == msgid && data != nil) {
         const void *bytes = [data bytes];
         bytes += sizeof(int);
         int len = *((int*)bytes);  bytes += sizeof(int);
@@ -1049,8 +1045,9 @@ extern GuiFont gui_mch_retain_font(GuiFont font);
             char_u *str = (char_u*)bytes;
             if ((str[0] == Ctrl_C && ctrl_c_interrupts) ||
                     (str[0] == intr_char && intr_char != Ctrl_C)) {
-                shouldClearQueue = YES;
                 got_int = TRUE;
+                [inputQueue removeAllObjects];
+                return;
             }
         }
     } else if (TerminateNowMsgID == msgid) {
@@ -1061,11 +1058,6 @@ extern GuiFont gui_mch_retain_font(GuiFont font);
         return;
     }
 
-    if (shouldClearQueue) {
-        [inputQueue removeAllObjects];
-        return;
-    }
-
     // Remove all previous instances of this message from the input queue, else
     // the input queue may fill up as a result of Vim not being able to keep up
     // with the speed at which new messages are received.
diff --git a/src/MacVim/MMTextViewHelper.m b/src/MacVim/MMTextViewHelper.m
index 295304665b..8494575017 100644
--- a/src/MacVim/MMTextViewHelper.m
+++ b/src/MacVim/MMTextViewHelper.m
@@ -264,10 +264,14 @@ static float MMDragAreaSize = 73.0f;
     if ([unmodchars isEqual:@"?"])
         return NO;
 
-    // Cmd-. is hard-wired to send an interrupt (like Ctrl-C).
+    // Cmd-. is hard-wired to send SIGINT unlike Ctrl-C which is just another
+    // key press which Vim has to interpret.  This means that Cmd-. always
+    // works to interrupt a Vim process whereas Ctrl-C can suffer from problems
+    // such as dropped DO messages (or if Vim is stuck in a loop without
+    // checking for keyboard input).
     if ((flags & NSDeviceIndependentModifierFlagsMask) == NSCommandKeyMask &&
             [unmodchars isEqual:@"."]) {
-        [[self vimController] sendMessage:InterruptMsgID data:nil];
+        kill([[self vimController] pid], SIGINT);
         return YES;
     }
 
diff --git a/src/MacVim/MacVim.h b/src/MacVim/MacVim.h
index 88e5e3c0a5..2f52306061 100644
--- a/src/MacVim/MacVim.h
+++ b/src/MacVim/MacVim.h
@@ -174,7 +174,6 @@ enum {
     SetDocumentFilenameMsgID,
     OpenWithArgumentsMsgID,
     CloseWindowMsgID,
-    InterruptMsgID,
     SetFullscreenColorMsgID,
     ShowFindReplaceDialogMsgID,
     FindReplaceMsgID,
diff --git a/src/MacVim/MacVim.m b/src/MacVim/MacVim.m
index dd6d21ea5a..c361be302e 100644
--- a/src/MacVim/MacVim.m
+++ b/src/MacVim/MacVim.m
@@ -81,7 +81,6 @@ char *MessageStrings[] =
     "SetDocumentFilenameMsgID",
     "OpenWithArgumentsMsgID",
     "CloseWindowMsgID",
-    "InterruptMsgID",
     "SetFullscreenColorMsgID",
     "ShowFindReplaceDialogMsgID",
     "FindReplaceMsgID",
diff --git a/src/MacVim/gui_macvim.m b/src/MacVim/gui_macvim.m
index cea57bbdd0..25d5ade70a 100644
--- a/src/MacVim/gui_macvim.m
+++ b/src/MacVim/gui_macvim.m
@@ -189,7 +189,8 @@ gui_mch_update(void)
     // interrupt Vim by presssing Ctrl-C during lengthy operations (e.g. after
     // entering "10gs" it would not be possible to bring Vim out of the 10 s
     // sleep prematurely).  As a compromise we check for Ctrl-C only once per
-    // second.
+    // second.  Note that Cmd-. sends SIGINT so it has higher success rate at
+    // interrupting Vim.
     static CFAbsoluteTime lastTime = 0;
 
     CFAbsoluteTime nowTime = CFAbsoluteTimeGetCurrent();