Re: lua5.1: Lua stack is too small for a script that takes over 2048 arguments

[Gé Weijers <ge@...>]

This is a bit of a problem.

Alternatively the arguments could be passed in as a single argument,  
i.e. an array, or a userdata object pretending to be a read-only  
array (implementing the length and index operations). The userdata  
object would not require the allocation of a potentially massive  
array to store a copy of the argument vector, but would copy the  
contents of 'argv' to the lua interpreter one string at a time.

The worst case argument vector would be about ARG/MAX zero-byte  
strings, which would require LUAI_MAXCSTACK to be equal to ARG_MAX,  
i.e. insanely large.

Gé

On Dec 19, 2007, at 4:03 PM, Norman Ramsey wrote:

> Package: lua5.1
> Version: 5.1.2-4
> Severity: normal
>
> I just got this rather unhappy result:
>
> : nr@homedog 10445 ; label-by-hand -udir /home/nr/tmp/tt2 *
> lua5.1: stack overflow (too many arguments to script)
>
>
> It seems to me that the Lua interpreter should accept as many
> arguments as the local operating system is willing to provide.  This
> number is fairly fuzzy (see http://tinyurl.com/nn8yd for a good
> discussion of the issues), but the current default of 2048 is
> unreasonably small for a stock Debian system.  ARG_MAX is 131072 on
> this system, so supposing we assume each argument is an 8.3 pathname
> with a trailing null, even leaving room for some environment this is
> space for about ten thousand arguments.  I suggest that when Lua is
> built for Debian that line 445 of luaconf.h be changed so that
> LUAI_MAXCSTACK is more in that range.
>
>
> Norman
>
>
> -- System Information:
> Debian Release: lenny/sid
>   APT prefers testing
>   APT policy: (500, 'testing'), (500, 'stable'), (50, 'unstable')
> Architecture: i386 (i686)
>
> Kernel: Linux 2.6.22-3-k7 (SMP w/2 CPU cores)
> Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968)
> Shell: /bin/sh linked to /bin/bash
>
> Versions of packages lua5.1 depends on:
> ii  libc6                         2.7-3      GNU C Library: Shared  
> libraries
> ii  libreadline5                  5.2-3      GNU readline and  
> history libraries
>
> lua5.1 recommends no packages.
>
> -- no debconf information

--
Gé Weijers
ge@weijers.org