[ITP] libfakesu 1.0

Christian Franke Christian.Franke@t-online.de
Wed Sep 10 12:46:00 GMT 2014

D. Boland wrote:
> Christian Franke wrote:
>> D. Boland wrote:
>>> http://cygwin.boland.nl/x86/release/libfakesu/
>> A few notes regarding cygfakesu.c:
>>> uid_t root_uid = 18;
>>> gid_t root_gid = 544;
>>> uid_t my_uid = -1;
>>> gid_t my_gid = -1;
>>> struct passwd my_pw;
>>> struct group my_grp;
>>> char str255[255];
>>> ...
>>> uid_t uid_get(uid_t uid){
>>> ...
>>> gid_t gid_get(gid_t gid){
>>> ...
>>> etc...
>> Variables and functions not exported by the fakesu.h file should be
>> declared as static. Note that the cygfakesu.def file has no effect when
>> generating a static lib.
> I added 'static' for un-exported symbols. Removed cygfakesu.def.


BTW: All these variables except root_uid/gid are not needed as static 

my_uid is only used to pass the uid from uid_get/set() to get/set(e)uid().

my_pw and str255 are only needed because su_getpwnam() calls 
getpwnam_r() instead of getpwnam().


>>> int su_setgroups(int size, const gid_t *list){
>>> ...
>>>      gid_t l[s];
>>> ...
>>>      return setgroups(size, &l);
>> setgroups() 2nd parameter expects a type compatible to 'pointer to const
>> git_t'
>> The type of '&l' is 'pointer to array of git_t' :-)
>> (cosmetic in C, compilation would fail in C++):
> I added typecasting, like this:
> 	return setgroups(size, (gid_t *) &l);

No cast is needed, simply remove the '&' operator:

   return setgroups(size, l);

Remember that a C array is implicitly converted to 'pointer to first 
element' in many cases, including the above.

Another unrelated suggestion:

Add defines to fakesu.h for other uid/gid related functions which are 
not implemented by fakesu:

#define setreuid(a,b)  getruid_MISSING(a,b)
#define getpwnam_r(a,b,c,d,e)  getpwnam_r_MISSING(a,b,c,d,e)


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