tests/getgroups.c

   1 /* this tests whether getgroups actually returns lists of integers
   2    rather than gid_t. The test only works if the user running
   3    the test is in at least 1 group
   4
   5    The test is designed to check for those broken OSes that define
   6    getgroups() as returning an array of gid_t but actually return a
   7    array of ints! Ultrix is one culprit
   8   */
   9
  10 #if defined(HAVE_UNISTD_H)
  11 #include <unistd.h>
  12 #endif
  13
  14 #include <sys/types.h>
  15 #include <stdio.h>
  16 #include <unistd.h>
  17 #include <grp.h>
  18
  19 int main(void)
  20 {
  21         int i;
  22         int *igroups;
  23         char *cgroups;
  24         int grp = 0;
  25         int  ngroups = getgroups(0,&grp);
  26
  27         if (sizeof(gid_t) == sizeof(int)) {
  28                 fprintf(stderr,"gid_t and int are the same size\n");
  29                 exit(1);
  30         }
  31
  32         if (ngroups <= 0)
  33                 ngroups = 32;
  34
  35         igroups = (int *)malloc(sizeof(int)*ngroups);
  36
  37         for (i=0;i<ngroups;i++)
  38                 igroups[i] = 0x42424242;
  39
  40         ngroups = getgroups(ngroups,(gid_t *)igroups);
  41
  42         if (igroups[0] == 0x42424242)
  43                 ngroups = 0;
  44
  45         if (ngroups == 0) {
  46                 printf("WARNING: can't determine getgroups return type\n");
  47                 exit(1);
  48         }
  49
  50         cgroups = (char *)igroups;
  51
  52         if (ngroups == 1 &&
  53             cgroups[2] == 0x42 && cgroups[3] == 0x42) {
  54                 fprintf(stderr,"getgroups returns gid_t\n");
  55                 exit(1);
  56         }
  57
  58         for (i=0;i<ngroups;i++) {
  59                 if (igroups[i] == 0x42424242) {
  60                         fprintf(stderr,"getgroups returns gid_t\n");
  61                         exit(1);
  62                 }
  63         }
  64
  65         exit(0);
  66 }