non-busybox dhcp clients (was: PATCH: ifupdown.c, udhcpc, and standalone shell)

[Denis Vlasenko]

On Tuesday 10 October 2006 17:52, Gabriel L. Somlo wrote:
> Denis,
> 
> I just realized that my 'execable' patch was done before the migration
> to kbuild, so here it goes again.
> 
> First three diffs add execable to libbb (execable.c, libbb.h, and
> libbb/Kbuild)

+       char *path = xstrdup(getenv("PATH"));

What if getenv returns NULL?

+       char *p, *n, *r, *ret = NULL;
+
+       p = path;
+       while (p) {
+               n = strchr(p, ':');
+               if (n)
+                       *n++ = '\0';
+               if (*p != '\0') { /* handle PATH=":foo::bar:" situation */
+                       r = concat_path_file(p, filename);
+                       if (execable_file(r)) {
+                               ret = r;
+                               break;
+                       }
+                       free(r);
+               }
+               p = n;
+       }
+       if (path)
+               free(path);

path is always !NULL.

+       return ret;

> 
> Next diff modifies ifupdown.c to use udhcpc if built-in or find an
> external client by searching the $PATH using execable.

+       bb_error_msg("No dhcp clients found.");

bb_error_msg("no dhcp clients found") because it really prints:

<applet>: no dhcp clients found

> Last diff is against debianutils/which.c and makes it much simpler and
> more readable by calling execable to find things in $PATH.

+                       if ((p = find_execable(*argv)))

Obfuscated C contest again.

> Please apply.

Applied. Please test svn version.
--
vda