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+/*
+ * Copyright (c) 1991 - 1993, Julianne Frances Haugh
+ * Copyright (c) 1996 - 2000, Marek Michałkiewicz
+ * Copyright (c) 2001 - 2006, Tomasz Kłoczko
+ * Copyright (c) 2007 - 2008, Nicolas François
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the copyright holders or contributors may not be used to
+ * endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <config.h>
+
+#ident "$Id$"
+
+#include <grp.h>
+#include <pwd.h>
+#include <stdio.h>
+#include "defines.h"
+#include "prototypes.h"
+/*
+ * Global variables
+ */
+const char *Prog;
+
+/* local function prototypes */
+static void print_groups (const char *member);
+
+/*
+ * print_groups - print the groups which the named user is a member of
+ *
+ * print_groups() scans the groups file for the list of groups which
+ * the user is listed as being a member of.
+ */
+static void print_groups (const char *member)
+{
+ int groups = 0;
+ struct group *grp;
+ struct passwd *pwd;
+ bool flag = false;
+
+ pwd = getpwnam (member); /* local, no need for xgetpwnam */
+ if (NULL == pwd) {
+ (void) fprintf (stderr, _("%s: unknown user %s\n"),
+ Prog, member);
+ exit (EXIT_FAILURE);
+ }
+
+ setgrent ();
+ while ((grp = getgrent ()) != NULL) {
+ if (is_on_list (grp->gr_mem, member)) {
+ if (0 != groups) {
+ (void) putchar (' ');
+ }
+ groups++;
+
+ (void) printf ("%s", grp->gr_name);
+ if (grp->gr_gid == pwd->pw_gid) {
+ flag = true;
+ }
+ }
+ }
+ endgrent ();
+
+ /* The user may not be in the list of members of its primary group */
+ if (!flag) {
+ grp = getgrgid (pwd->pw_gid); /* local, no need for xgetgrgid */
+ if (NULL != grp) {
+ if (0 != groups) {
+ (void) putchar (' ');
+ }
+ groups++;
+
+ (void) printf ("%s", grp->gr_name);
+ }
+ }
+
+ if (0 != groups) {
+ (void) putchar ('\n');
+ }
+}
+
+/*
+ * groups - print out the groups a process is a member of
+ */
+int main (int argc, char **argv)
+{
+#ifdef HAVE_GETGROUPS
+ long sys_ngroups;
+ GETGROUPS_T *groups;
+#else
+ char *logname;
+ char *getlogin ();
+#endif
+
+#ifdef HAVE_GETGROUPS
+ sys_ngroups = sysconf (_SC_NGROUPS_MAX);
+ groups = (GETGROUPS_T *) malloc (sizeof (GETGROUPS_T) * sys_ngroups);
+#endif
+ (void) setlocale (LC_ALL, "");
+ (void) bindtextdomain (PACKAGE, LOCALEDIR);
+ (void) textdomain (PACKAGE);
+
+ /*
+ * Get the program name so that error messages can use it.
+ */
+ Prog = Basename (argv[0]);
+
+ if (argc == 1) {
+
+ /*
+ * Called with no arguments - give the group set for the
+ * current user.
+ */
+
+#ifdef HAVE_GETGROUPS
+ int i;
+ int pri_grp; /* TODO: should be GETGROUPS_T */
+ /*
+ * This system supports concurrent group sets, so I can ask
+ * the system to tell me which groups are currently set for
+ * this process.
+ */
+ int ngroups = getgroups (sys_ngroups, groups);
+ if (ngroups < 0) {
+ perror ("getgroups");
+ exit (EXIT_FAILURE);
+ }
+
+ /*
+ * The groupset includes the primary group as well.
+ */
+ pri_grp = getegid ();
+ for (i = 0; i < ngroups; i++) {
+ if (pri_grp == (int) groups[i]) {
+ break;
+ }
+ }
+
+ if (i != ngroups) {
+ pri_grp = -1;
+ }
+
+ /*
+ * Print out the name of every group in the current group
+ * set. Unknown groups are printed as their decimal group ID
+ * values.
+ */
+ if (-1 != pri_grp) {
+ struct group *gr;
+ /* local, no need for xgetgrgid */
+ gr = getgrgid (pri_grp);
+ if (NULL != gr) {
+ (void) printf ("%s", gr->gr_name);
+ } else {
+ (void) printf ("%d", pri_grp);
+ }
+ }
+
+ for (i = 0; i < ngroups; i++) {
+ struct group *gr;
+ if ((0 != i) || (-1 != pri_grp)) {
+ (void) putchar (' ');
+ }
+
+ /* local, no need for xgetgrgid */
+ gr = getgrgid (groups[i]);
+ if (NULL != gr) {
+ (void) printf ("%s", gr->gr_name);
+ } else {
+ (void) printf ("%ld", (long) groups[i]);
+ }
+ }
+ (void) putchar ('\n');
+#else
+ /*
+ * This system does not have the getgroups() system call, so
+ * I must check the groups file directly.
+ */
+ logname = getlogin ();
+ if (NULL != logname) {
+ print_groups (logname);
+ } else {
+ exit (EXIT_FAILURE);
+ }
+#endif
+ } else {
+
+ /*
+ * The invoker wanted to know about some other user. Use
+ * that name to look up the groups instead.
+ */
+ print_groups (argv[1]);
+ }
+ return EXIT_SUCCESS;
+}
+