On Thu, 2011-07-21 at 18:51 +0200, Karel Zak wrote:
> On Wed, Jul 20, 2011 at 12:46:25AM -0400, Davidlohr Bueso wrote:
> > From: Davidlohr Bueso <dave@xxxxxxx>
> > Date: Wed, 20 Jul 2011 00:39:10 -0400
> >
> > Currently this tool only uses the hardcoded paths for looking up
> > strings for binaries, man pages and source code, adding those
> > directories found in $PATH makes a nice little enhancement.
>
> Finally someone who is not lazy to implement it correctly :-)
...
> man getenv, you should not modify the result from getenv().
ouch, sorry!
>
> > + if (!tok)
> > + break;
> > + if (inpath(tok)) /* make sure we don't repeat the search path */
> > + continue;
> > +
> > + pathdir = xrealloc(pathdir, (i + 1) * sizeof(char *));
> > + pathdir[i++] = tok;
> > + }
>
> here is bug, see below to gdb backtrace...
>
> > +
> > void
> > getlist(int *argcp, char ***argvp, char ***flagp, int *cntp)
> > {
> > @@ -356,6 +407,8 @@ find(char **dirs, char *cp)
> > {
> > while (*dirs)
> > findin(*dirs++, cp);
> > + while(*dirp)
> ^^^^^^
> > + findin(*dirp++, cp);
>
> ... this code expects that the array is terminated by zero.
>
> Note that find() is called always for all dir lists.
>
> Maybe it would be better to add lookpathenv() and call it from
> print_again(). You can also add -p options to control this behavior.
> See how {s,b,m}flags work.
That was my initial design, however since src, bin and man are _types_
of files, it seems that adding a similar behavior for search _paths_ is
like mixing apples and pears.
Something I am thinking of, but won't do it quite yet, is to simply
rewrite whereis and, instead of hardcoding paths, recursively search
from / and use stat + heuristics to differentiate the different files.
>
> BTW, the whole whereis code is horrible,
Like most BSD '80s code is. I was hoping you weren't going to ask for
cleanups :)
> for example find() is completely
> unnecessary if there is also findv() and all lists of the directories are
> static. It should be possible to use
>
> findv(ary, ARRAY_SIZE(ary), str);
>
> everywhere instead of find(ary, str);
>
> Karel
>
> Starting program: /home/projects/util-linux/util-linux/misc-utils/whereis lsblk
>
> Program received signal SIGSEGV, Segmentation fault.
That'll teach me not to code half asleep. I'm sending you some cleanup
patches and then I'll add these fixes to the program.
> 0x0000003cbae7edfa in __strchr_sse2 () from /lib64/libc.so.6
> Missing separate debuginfos, use: debuginfo-install glibc-2.14-4.x86_64
> (gdb) bt
> #0 0x0000003cbae7edfa in __strchr_sse2 () from /lib64/libc.so.6
> #1 0x00000000004013c8 in findin (dir=0x1ff41 <Address 0x1ff41 out of bounds>,
> cp=0x7fffffffe477 "lsblk") at whereis.c:434
> #2 0x0000000000401623 in find (dirs=<optimized out>,
> cp=0x7fffffffe477 "lsblk") at whereis.c:421
> #3 0x00000000004017a8 in print_again (cp=0x7fffffffe477 "lsblk")
> at whereis.c:327
> #4 0x0000000000401870 in lookup (cp=0x7fffffffe477 "lsblk") at whereis.c:374
> #5 0x0000000000400c9b in main (argc=1, argv=0x7fffffffe148) at whereis.c:242
- Davidlohr
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