BusyBox 1.11.0 man patch for "cat"

[Denys Vlasenko]

On Saturday 05 July 2008 11:02, Jason Curl wrote:
> I've checked your fix Denys and it also works (I don't get segfaults 
> anymore). I've taken the code from my second patch, checked it against 
> the latest snapshot and found I can reduce the size of man a bit more by 
> removing the two instances of the format string when generating the man 
> filename. I think the code is much more cryptic, but it's a small piece.

+                                       int mode = 0;
 -                                      /* Search for cat page first */
-                                       man_filename = xasprintf("%.*s/%s%.*s/%s.%.*s" ".bz2",

Interesting patch format.

                                        char *man_filename;
-                                       int found_here;
+                                       int mode = 0;
-                                       /* Search for cat page first */
-                                       man_filename = xasprintf("%.*s/%s%.*s/%s.%.*s" ".bz2",
-                                                       path_len, cur_path,
-                                                       "cat",
-                                                       sect_len, cur_sect,
-                                                       *argv,
-                                                       sect_len, cur_sect);
-                                       found_here = show_manpage(pager, man_filename, 1);
-                                       free(man_filename);
-                                       if (!found_here) {
+                                       /* We search first for a cat page, then for a man page */
+                                       while (mode < 2) {
                                                man_filename = xasprintf("%.*s/%s%.*s/%s.%.*s" ".bz2",
-                                                       path_len, cur_path,
-                                                       "man",
-                                                       sect_len, cur_sect,
-                                                       *argv,
-                                                       sect_len, cur_sect);
-                                               found_here = show_manpage(pager, man_filename, 0);
+                                                               path_len, cur_path,
+                                                               mode?"man":"cat",
+                                                               sect_len, cur_sect,
+                                                               *argv,
+                                                               sect_len, cur_sect);
+                                               found = show_manpage(pager, man_filename, 1-mode);
                                                free(man_filename);
+                                               mode += found + 1;
                                        }
-                                       found |= found_here;
                                        if (found && !(opt & OPT_a))
                                                goto next_arg;


"found |= found_here;" was there for a reason:

If no man page is found, we need to report that.
With "man -a", we are getting false negative (found == 0) -
man thinks that page is not found, whereas it's "page is not found
_in last man directory_".

But overall idea is good and I incorporated it in man.c now.
Thanks.
--
vda