+enum nss_status
+get_local_group(const char *name, struct group *grp, char *buffer, size_t buflen, int *errnop)
+{
+ static const char *fct_name = "getgrnam_r";
+ static service_user *startp = NULL;
+ static void *fct_start = NULL;
+ enum nss_status status;
+ service_user *nip;
+ union {
+ enum nss_status (*l)(const char *name, struct group *grp,
+ char *buffer, size_t buflen, int *errnop);
+ void *ptr;
+ } fct;
+ struct group gbuf;
+ int n;
+ int old_errno = errno;
+
+ int len = sysconf(_SC_GETGR_R_SIZE_MAX);
+ char *buf = malloc(len);
+ if (buf == NULL) {
+ *errnop = ENOMEM;
+ errno = old_errno;
+ return NSS_STATUS_TRYAGAIN;
+ }
+
+ if (fct_start == NULL &&
+ __nss_group_lookup(&startp, fct_name, &fct_start) != 0) {
+ free(buf);
+ return NSS_STATUS_UNAVAIL;
+ }
+ nip = startp;
+ fct.ptr = fct_start;
+ do {
+ if (fct.l == _nss_nonlocal_getgrnam_r)
+ status = NSS_STATUS_NOTFOUND;
+ else
+ status = DL_CALL_FCT(fct.l, (name, &gbuf, buf, buflen, errnop));
+ if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
+ break;
+ } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
+
+ if (status == NSS_STATUS_SUCCESS) {
+ n = snprintf(buffer, buflen, "%s", gbuf.gr_name);
+ if (n < 0 || n >= buflen) {
+ *errnop = ERANGE;
+ status = NSS_STATUS_TRYAGAIN;
+ goto get_local_group_done;
+ }
+ grp->gr_name = buffer;
+ buffer += n;
+ buflen -= n;
+
+ n = snprintf(buffer, buflen, "%s", gbuf.gr_passwd);
+ if (n < 0 || n >= buflen) {
+ *errnop = ERANGE;
+ status = NSS_STATUS_TRYAGAIN;
+ goto get_local_group_done;
+ }
+ grp->gr_passwd = buffer;
+ buffer += n;
+ buflen -= n;
+
+ grp->gr_gid = gbuf.gr_gid;
+
+ if (buflen < sizeof(void *)) {
+ *errnop = ERANGE;
+ status = NSS_STATUS_TRYAGAIN;
+ goto get_local_group_done;
+ }
+ *(void **)buffer = NULL;
+ buffer += sizeof(void *);
+ buflen -= sizeof(void *);
+ }
+
+ get_local_group_done:
+ free(buf);
+ return status;
+}