[patch] let binfmt_misc optionally preserve argv[1]

From: David Mosberger (davidm@napali.hpl.hp.com)
Date: Wed Nov 06 2002 - 13:19:17 EST

Hi Linus,

Below is a patch which makes it possible for binfmt_misc to optionally
preserve the contents of argv[1]. This is needed for building
accurate simulators which are invoked via binfmt_misc. I had brought
up this patch a while ago (see URL below) and there was no negative
feedback (OK, there was no feedback at all... ;-).

The patch is trivial and the new behavior is triggered only if the
letter "P" (for "preserve") is appended to the binfmt_misc
registration string, so it shold be completely safe.

Thanks,

        --david

http://groups.google.com/groups?q=mosberger+binfmt_misc&hl=en&lr=&ie=UTF-8&oe=UTF-8&selm=200209092241.g89MfPS5001013%40napali.hpl.hp.com&rnum=1

diff -Nru a/fs/binfmt_misc.c b/fs/binfmt_misc.c
--- a/fs/binfmt_misc.c Tue Sep 24 22:09:20 2002
+++ b/fs/binfmt_misc.c Tue Sep 24 22:09:20 2002
@@ -36,6 +36,7 @@
 static int enabled = 1;
 
 enum {Enabled, Magic};
+#define MISC_FMT_PRESERVE_ARGV0 (1<<31)
 
 typedef struct {
         struct list_head list;
@@ -124,7 +125,9 @@
         bprm->file = NULL;
 
         /* Build args for interpreter */
- remove_arg_zero(bprm);
+ if (!(fmt->flags & MISC_FMT_PRESERVE_ARGV0)) {
+ remove_arg_zero(bprm);
+ }
         retval = copy_strings_kernel(1, &bprm->filename, bprm);
         if (retval < 0) goto _ret;
         bprm->argc++;
@@ -289,6 +292,11 @@
         *p++ = '\0';
         if (!e->interpreter[0])
                 goto Einval;
+
+ if (*p == 'P') {
+ p++;
+ e->flags |= MISC_FMT_PRESERVE_ARGV0;
+ }
 
         if (*p == '\n')
                 p++;
-
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This archive was generated by hypermail 2b29 : Thu Nov 07 2002 - 22:00:44 EST