On February 14, 2015 5:08:23 AM CST, Andrew Haley <[email protected]> wrote:
>On 13/02/15 22:40, Cyd Haselton wrote:
>> Somehow these calls are passed to libc by the wrapper including the
>dlopen() call...which fails because it should be passed to libdl on
>android.
>>
>> How the wrapper points to libc I have no idea. Why the wrapper
>around dlopen doesn't pick up 0n the linked libdl.so...again, I have no
>idea. Someone with better knowledge of fakechroot internals, symbols
>and linking will have to tackle this.
>
>Ah, I think I might know. When you call dlsym() you have the option
>of passing a handle to the library you want to search. Usually
>dlsym() searches all loaded libraries, but it's possible that
>libfakechroot specifies that only libc is searched.
>
>Andrew.
Given that info...and in spite of my aforementioned limited knowledge I went
back to take another look at the source and found this in libfakechroot.c
/bld/fakechrt/fakechroot-2.16 $ grep -C 4 dlsym src/libfakechroot.c
/* Lazily load function */
LOCAL fakechroot_wrapperfn_t fakechroot_loadfunc (struct fakechroot_wrapper * w)
{
char *msg;
if (!(w->nextfunc = dlsym(RTLD_NEXT, w->name))) {;
msg = dlerror();
fprintf(stderr, "%s: %s: %s\n", PACKAGE, w->name, msg != NULL ? msg :
"unresolved symbol");
exit(EXIT_FAILURE);
}
I'm fairly certain I remember reading something about Android and lazy function
loading....how it doesn't handle it well or does so differently from standard
Linux builds. At any rate, I believe the above code is responsible for those
annoying 'fakechroot: undefined reference to dlopen' errors, so I'll see if I
can fix that.
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
