Re: [Chicken-hackers] [PATCH] Prevent running applications from crashing when reinstalling

[Peter Bex]

On Thu, Oct 04, 2012 at 08:27:43PM +0200, Felix wrote:
> Here a suggestion which ought to work better:
> 
> diff --git a/setup-api.scm b/setup-api.scm
> index 50ab484..0f54b9c 100644
> --- a/setup-api.scm
> +++ b/setup-api.scm
> @@ -509,6 +509,9 @@
>             (directory from)))
>           (else
>            (ensure-directory to)
> +          (when (and (file-exists? to)
> +                       (not (directory? to)))
> +            (remove-file* to))
>            (run (,*copy-command* 
>                  ,(shellpath from)
>                  ,(shellpath to))))))

This doesn't fix things like setup-api where "from" is a .so-file
and "to" is a directory.  This will still cause a crash for those eggs.
I'm not sure whether we can expect people to just pass a proper copy
command, or if we need to handle this case properly.

This is probably more thorough:

diff --git a/setup-api.scm b/setup-api.scm
index 50ab484..fed6b67 100644
--- a/setup-api.scm
+++ b/setup-api.scm
@@ -509,9 +509,13 @@
              (directory from)))
            (else
             (ensure-directory to)
-            (run (,*copy-command* 
-                  ,(shellpath from)
-                  ,(shellpath to))))))
+             (let ((to-file (if (directory? to)
+                                (make-pathname to (pathname-strip-directory 
from))
+                                to)))
+               (remove-file* to-file)
+               (run (,*copy-command* 
+                     ,(shellpath from)
+                     ,(shellpath to-file)))))))
     to))
 
 (define (path-prefix? pref path)


> Since all that file-handling mess in setup-api.scm confuses me, I
> can't say that I'm absolutely sure that this handles all cases (We
> need a new setup API - one that is so simple and straightforward that
> it just can not be used wrongly).

I agree, but this will take quite a while.  In the meanwhile, this might
be a nice fix.

Cheers,
Peter
-- 
http://sjamaan.ath.cx
--
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