Preserve swap files after crash

Before terminating gracefully, send a TerminateNowMsgID to every Vim process so
that they can determine whether MacVim quit or crashed.  If MacVim quits, call
getout() to exit Vim (this removes swap files), otherwise call
getout_preserve_modified() (this preserves swap files).

src/MacVim/MMAppController.m

@@ -198,7 +198,7 @@ static NSTimeInterval MMReplyTimeout = 5;
     // 'documentEdited' flag of the window correspondingly.)
     NSEnumerator *e = [[NSApp windows] objectEnumerator];
     id window;
-    while (window = [e nextObject]) {
+    while ((window = [e nextObject])) {
         if ([window isDocumentEdited]) {
             modifiedBuffers = YES;
             break;
@@ -220,6 +220,15 @@ static NSTimeInterval MMReplyTimeout = 5;
         [alert release];
     }
 
+    // Tell all Vim processes to terminate now (otherwise they'll leave swap
+    // files behind).
+    if (NSTerminateNow == reply) {
+        e = [vimControllers objectEnumerator];
+        id vc;
+        while ((vc = [e nextObject]))
+            [vc sendMessage:TerminateNowMsgID data:nil];
+    }
+
     return reply;
 }
 

src/MacVim/MMBackend.h

@@ -44,6 +44,7 @@
     NSString            *alternateServerName;
     ATSFontContainerRef fontContainerRef;
     NSFont              *oldWideFont;
+    BOOL                isTerminating;
 }
 
 + (MMBackend *)sharedInstance;

src/MacVim/MMBackend.m

@@ -1133,6 +1133,8 @@ enum {
             [self addInput:string];
             [string release];
         }
+    } else if (TerminateNowMsgID == msgid) {
+        isTerminating = YES;
     } else {
         // Not keyboard or mouse event, queue it and handle later.
         //NSLog(@"Add event %s to input event queue", MessageStrings[msgid]);
@@ -1776,11 +1778,15 @@ enum {
 {
     // If the main connection to MacVim is lost this means that MacVim was
     // either quit (by the user chosing Quit on the MacVim menu), or it has
-    // crashed.  In either case our only option is to quit now.
-    // TODO: Write backup file?
+    // crashed.  In the former case the flag 'isTerminating' is set and we then
+    // quit cleanly; in the latter case we make sure the swap files are left
+    // for recovery.
 
-    //NSLog(@"A Vim process lost its connection to MacVim; quitting.");
-    getout(0);
+    NSLog(@"%s isTerminating=%d", _cmd, isTerminating);
+    if (isTerminating)
+        getout(0);
+    else
+        getout_preserve_modified(1);
 }
 
 - (void)blinkTimerFired:(NSTimer *)timer

src/MacVim/MacVim.h

@@ -156,6 +156,7 @@ enum {
     BuffersModifiedMsgID,
     AddInputMsgID,
     SetPreEditPositionMsgID,
+    TerminateNowMsgID,
 };
 
 

src/MacVim/MacVim.m

@@ -69,6 +69,7 @@ char *MessageStrings[] =
     "BuffersModifiedMsgID",
     "AddInputMsgID",
     "SetPreEditPositionMsgID",
+    "TerminateNowMsgID",
 };
 
 

src/main.c

@@ -1226,7 +1226,8 @@ main_loop(cmdwin, noexmode)
 }
 
 
-#if defined(USE_XSMP) || defined(FEAT_GUI_MSWIN) || defined(PROTO)
+#if defined(USE_XSMP) || defined(FEAT_GUI_MSWIN) || defined(PROTO) \
+	|| defined(FEAT_GUI_MACVIM)
 /*
  * Exit, but leave behind swap files for modified buffers.
  */