From 9d6fbc71c9e4f235900e0bf0547fef9a98f689d9 Mon Sep 17 00:00:00 2001
From: Mark Wooding <mdw@distorted.org.uk>
Date: Mon, 28 Apr 2014 10:02:26 +0100
Subject: [PATCH] frontend.lisp: New `-D' option to generate stack backtrace on
 error.

This is a frequent debugging modification, so I might as well make it
official.

The fundamental problem is that tracking down errors in a zone
description file is a complete nightmare.  This needs fixing some time.
---
 frontend.lisp | 39 ++++++++++++++++++++++++---------------
 1 file changed, 24 insertions(+), 15 deletions(-)

diff --git a/frontend.lisp b/frontend.lisp
index f957601..5a3bb7a 100644
--- a/frontend.lisp
+++ b/frontend.lisp
@@ -32,6 +32,8 @@
   "Which zones to be emitted.")
 (defvar opt-format :bind
   "Which format to use on output.")
+(defvar opt-debug nil
+  "Whether to emit stack backtraces on error.")
 
 (defun directory-exists-p (name)
 
@@ -71,6 +73,8 @@
 		      (#\s "subnet" (:arg "NET")
 			   (list zone:*preferred-subnets*)
 			   "Designate NET as a preferred subnet.")
+		      (#\D "debug" (set opt-debug)
+			   "Produce stack backtrace on error.")
 		      "Output options"
 		      (#\d "directory" (:arg "DIRECTORY")
 			   (dir *zone-output-path*)
@@ -94,20 +98,25 @@
 
 (defun main ()
   (set-command-line-arguments)
-  (with-unix-error-reporting ()
-    (let ((files nil))
-      (unless (option-parse-try
-		(do-options ()
-		  (nil (rest)
-		    (when (zerop (length rest))
-		      (option-parse-error "no files to read"))
-		    (setf files rest))))
-	(die-usage))
-      (dolist (f files)
-	(let ((*package* (make-package "ZONE.SCRATCH"
-				       :use '(#:common-lisp #:net #:zone))))
-	  (load f :verbose nil :print nil :if-does-not-exist :error)
-	  (delete-package *package*)))
-      (zone-save opt-zones :format opt-format))))
+  (let ((files nil))
+    (flet ((run ()
+	     (dolist (f files)
+	       (let ((*package* (make-package "ZONE.SCRATCH"
+					      :use '(#:common-lisp
+						     #:net #:zone))))
+		 (load f :verbose nil :print nil :if-does-not-exist :error)
+		 (delete-package *package*)))
+	     (zone-save opt-zones :format opt-format)))
+      (with-unix-error-reporting ()
+	(unless (option-parse-try
+		  (do-options ()
+		    (nil (rest)
+			 (when (zerop (length rest))
+			   (option-parse-error "no files to read"))
+			 (setf files rest))))
+	  (die-usage)))
+      (if opt-debug
+	  (run)
+	  (with-unix-error-reporting () (run))))))
 
 ;;;----- That's all, folks --------------------------------------------------
-- 
2.11.0