I very rarely use fortune and I'm not familiar with the codebase, but
from some quick testing and code-scanning I found the following:
is_fortfile appends .dat to the input file and sees if it's accessible.
Adding a symlink to the corresponding .dat file make the thing work
perfectly well for me. Your diff seems to work, because you resolve
the path, which in turn gives back the correct location for the .dat,
not because symlinks are not suported.
Personally I don't see good reason to add the additional logic which
can be solved with a second simple symlink, but if others think it's
worth it, comments inline.
martijn@
On Tue, 2020-12-15 at 01:09 +0300, Vadim Zhukov wrote:
> Hello, all.
>
> This allows fortune(6) to open fortune files via symlinks.
> Maybe this is a stupid idea, I dunno, but it seems inconsistent
> that I can't put a symlink to my fortunes collection in
> /usr/share/games/fortune and then simply call "fortune foo"
> instead of "fortune /usr/local/share/games/fortune/ru/foo".
>
> I decided to call readlink(2) explicitly rather than adding
> check of file type being open, since that resulted in less code.
>
> Ah, and yes, I have a port of Russian fortune files pending,
> but that's for another list and another day.
>
> So... okay/notokay anyone? :)
>
> --
> WBR,
> Vadim Zhukov
>
>
> Index: fortune.c
> ===================================================================
> RCS file: /cvs/src/games/fortune/fortune/fortune.c,v
> retrieving revision 1.60
> diff -u -p -r1.60 fortune.c
> --- fortune.c 10 Aug 2017 17:00:08 -0000 1.60
> +++ fortune.c 14 Dec 2020 22:05:33 -0000
> @@ -39,6 +39,7 @@
> #include <ctype.h>
> #include <dirent.h>
> #include <err.h>
> +#include <errno.h>
> #include <fcntl.h>
> #include <limits.h>
> #include <locale.h>
> @@ -388,8 +389,9 @@ add_file(int percent, char *file, char *
> FILEDESC *parent)
> {
> FILEDESC *fp;
> + ssize_t lnklen;
> int fd;
> - char *path, *offensive;
> + char *path, *offensive, lnkpath[PATH_MAX];
> bool was_malloc;
> bool isdir;
>
> @@ -420,8 +422,22 @@ add_file(int percent, char *file, char *
> }
>
> DPRINTF(1, (stderr, "adding file \"%s\"\n", path));
> +
> over:
> + lnklen = readlink(path, lnkpath, PATH_MAX);
I'd prefer sizeof(lnkpath) instead of PATH_MAX, just to be a little more
robust.
> + if (lnklen == -1) {
> + if (errno != EINVAL)
> + goto openfailed;
> + } else {
> + lnkpath[lnklen] = '\0';
> + if (was_malloc)
> + free(path);
> + path = strdup(lnkpath);
This needs a NULL-check.
> + was_malloc = 1;
> + }
> +
> if ((fd = open(path, O_RDONLY)) < 0) {
> +openfailed:
> /*
> * This is a sneak. If the user said -a, and if the
> * file we're given isn't a file, we check to see if
>
