--- src/iroffer_misc.c.orig	2011-08-14 22:08:43.000000000 +0200
+++ src/iroffer_misc.c	2011-08-14 22:11:44.000000000 +0200
@@ -22,6 +22,47 @@
 #include "dinoex_utilities.h"
 #include "dinoex_misc.h"
 
+int getgrouplist(const char *uname, gid_t agroup, gid_t *groups, int *grpcnt) {
+        const struct group *grp;
+        int i, maxgroups, ngroups, ret;
+
+        ret = 0;
+        ngroups = 0;
+        maxgroups = *grpcnt;
+        /*
+         * When installing primary group, duplicate it;
+         * the first element of groups is the effective gid
+         * and will be overwritten when a setgid file is executed.
+         */
+        groups[ngroups++] = agroup;
+        if (maxgroups > 1)
+                groups[ngroups++] = agroup;
+        /*
+         * Scan the group file to find additional groups.
+         */
+        setgrent();
+        while ((grp = getgrent()) != NULL) {
+                for (i = 0; i < ngroups; i++) {
+                        if (grp->gr_gid == groups[i])
+                                goto skip;
+                }
+                for (i = 0; grp->gr_mem[i]; i++) {
+                        if (!strcmp(grp->gr_mem[i], uname)) {
+                                if (ngroups >= maxgroups) {
+                                        ret = -1;
+                                        break;
+                                }
+                                groups[ngroups++] = grp->gr_gid;
+                                break;
+                        }
+                }
+skip:
+                ;
+        }
+        endgrent();
+        *grpcnt = ngroups;
+        return (ret);
+}
 
 void getconfig (void) {
    char *templine = mycalloc(maxtextlength);