Initial revision

1 files changed, 346 insertions, 0 deletions

diff --git a/src/id.c b/src/id.c
new file mode 100644
index 000000000..beddc1356
--- /dev/null
+++ b/src/id.c
@@ -0,0 +1,346 @@
+/* id -- print real and effective UIDs and GIDs
+   Copyright (C) 1989, 1991 Free Software Foundation.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+/* Written by Arnold Robbins, arnold@audiofax.com.
+   Major rewrite by David MacKenzie, djm@gnu.ai.mit.edu. */
+
+#include <stdio.h>
+#include <getopt.h>
+#include <sys/types.h>
+#include <pwd.h>
+#include <grp.h>
+#include "system.h"
+
+#ifdef _POSIX_VERSION
+#include <limits.h>
+#if !defined(NGROUPS_MAX) || NGROUPS_MAX < 1
+#define NGROUPS_MAX sysconf (_SC_NGROUPS_MAX)
+#endif /* !NGROUPS_MAX */
+
+/* Even though SunOS 4, Ultrix 4, and 386BSD are mostly POSIX.1 compliant,
+   their getgroups system call (except in the `System V' environment, which
+   is troublesome in other ways) fills in an array of int, not gid_t
+   (which is `short' on those systems).  Kludge, kludge.  */
+
+#if !defined(sun) && !defined(ultrix) && !defined(__386BSD__)
+#define GETGROUPS_T gid_t
+#else /* sun or ultrix or 386BSD */
+#define GETGROUPS_T int
+#endif /* sun or ultrix or 386BSD */
+#else /* not _POSIX_VERSION */
+struct passwd *getpwuid ();
+struct group *getgrgid ();
+uid_t getuid ();
+gid_t getgid ();
+uid_t geteuid ();
+gid_t getegid ();
+#include <sys/param.h>
+#if !defined(NGROUPS_MAX) && defined(NGROUPS)
+#define NGROUPS_MAX NGROUPS
+#endif /* not NGROUPS_MAX and NGROUPS */
+#define GETGROUPS_T int
+#endif /* not _POSIX_VERSION */
+
+char *xmalloc ();
+int getugroups ();
+void error ();
+void print_user ();
+void print_group ();
+void print_group_list ();
+void print_full_info ();
+void usage ();
+
+/* The name this program was run with. */
+char *program_name;
+
+/* If nonzero, output only the group ID(s). -g */
+int just_group = 0;
+
+/* If nonzero, output user/group name instead of ID number. -n */
+int use_name = 0;
+
+/* If nonzero, output real UID/GID instead of default effective UID/GID. -r */
+int use_real = 0;
+
+/* If nonzero, output only the user ID(s). -u */
+int just_user = 0;
+
+/* If nonzero, output only the supplementary groups. -G */
+int just_group_list = 0;
+
+/* The real and effective IDs of the user to print. */
+uid_t ruid, euid;
+gid_t rgid, egid;
+
+/* The number of errors encountered so far. */
+int problems = 0;
+
+struct option longopts[] =
+{
+  {"group", 0, NULL, 'g'},
+  {"name", 0, NULL, 'n'},
+  {"real", 0, NULL, 'r'},
+  {"user", 0, NULL, 'u'},
+  {"groups", 0, NULL, 'G'},
+  {NULL, 0, NULL, 0}
+};
+
+void
+main (argc, argv)
+     int argc;
+     char **argv;
+{
+  int optc;
+
+  program_name = argv[0];
+
+  while ((optc = getopt_long (argc, argv, "gnruG", longopts, (int *) 0))
+	 != EOF)
+    {
+      switch (optc)
+	{
+	case 'g':
+	  just_group = 1;
+	  break;
+	case 'n':
+	  use_name = 1;
+	  break;
+	case 'r':
+	  use_real = 1;
+	  break;
+	case 'u':
+	  just_user = 1;
+	  break;
+	case 'G':
+	  just_group_list = 1;
+	  break;
+	default:
+	  usage ();
+	}
+    }
+
+  if (just_user + just_group + just_group_list > 1)
+    error (1, 0, "cannot print only user and only group");
+
+  if (just_user + just_group + just_group_list == 0 && (use_real || use_name))
+    error (1, 0, "cannot print only names or real IDs in default format");
+
+  if (argc - optind > 1)
+    usage ();
+
+  if (argc - optind == 1)
+    {
+      struct passwd *pwd = getpwnam (argv[optind]);
+      if (pwd == NULL)
+	error (1, 0, "%s: No such user", argv[optind]);
+      ruid = euid = pwd->pw_uid;
+      rgid = egid = pwd->pw_gid;
+    }
+  else
+    {
+      euid = geteuid ();
+      ruid = getuid ();
+      egid = getegid ();
+      rgid = getgid ();
+    }
+
+  if (just_user)
+    print_user (use_real ? ruid : euid);
+  else if (just_group)
+    print_group (use_real ? rgid : egid);
+  else if (just_group_list)
+    print_group_list (argv[optind]);
+  else
+    print_full_info (argv[optind]);
+  putchar ('\n');
+
+  exit (problems != 0);
+}
+
+/* Print the name or value of user ID UID. */
+
+void
+print_user (uid)
+     int uid;
+{
+  struct passwd *pwd = NULL;
+
+  if (use_name)
+    {
+      pwd = getpwuid (uid);
+      if (pwd == NULL)
+	problems++;
+    }
+
+  if (pwd == NULL)
+    printf ("%u", (unsigned) uid);
+  else
+    printf ("%s", pwd->pw_name);
+}
+
+/* Print the name or value of group ID GID. */
+
+void
+print_group (gid)
+     int gid;
+{
+  struct group *grp = NULL;
+
+  if (use_name)
+    {
+      grp = getgrgid (gid);
+      if (grp == NULL)
+	problems++;
+    }
+
+  if (grp == NULL)
+    printf ("%u", (unsigned) gid);
+  else
+    printf ("%s", grp->gr_name);
+}
+
+/* Print all of the distinct groups the user is in . */
+
+void
+print_group_list (username)
+     char *username;
+{
+  print_group (rgid);
+  if (egid != rgid)
+    {
+      putchar (' ');
+      print_group (egid);
+    }
+
+#ifdef NGROUPS_MAX
+  {
+    int ngroups;
+    GETGROUPS_T *groups;
+    register int i;
+
+    groups = (GETGROUPS_T *) xmalloc (NGROUPS_MAX * sizeof (GETGROUPS_T));
+    if (username == 0)
+      ngroups = getgroups (NGROUPS_MAX, groups);
+    else
+      ngroups = getugroups (NGROUPS_MAX, groups, username);
+    if (ngroups < 0)
+      {
+	error (0, errno, "cannot get supplemental group list");
+	problems++;
+	free (groups);
+	return;
+      }
+
+    for (i = 0; i < ngroups; i++)
+      if (groups[i] != rgid && groups[i] != egid)
+	{
+	  putchar (' ');
+	  print_group (groups[i]);
+	}
+    free (groups);
+  }
+#endif
+}
+
+/* Print all of the info about the user's user and group IDs. */
+
+void
+print_full_info (username)
+     char *username;
+{
+  struct passwd *pwd;
+  struct group *grp;
+
+  printf ("uid=%u", (unsigned) ruid);
+  pwd = getpwuid (ruid);
+  if (pwd == NULL)
+    problems++;
+  else
+    printf ("(%s)", pwd->pw_name);
+  
+  printf (" gid=%u", (unsigned) rgid);
+  grp = getgrgid (rgid);
+  if (grp == NULL)
+    problems++;
+  else
+    printf ("(%s)", grp->gr_name);
+  
+  if (euid != ruid)
+    {
+      printf (" euid=%u", (unsigned) euid);
+      pwd = getpwuid (euid);
+      if (pwd == NULL)
+	problems++;
+      else
+	printf ("(%s)", pwd->pw_name);
+    }
+  
+  if (egid != rgid)
+    {
+      printf (" egid=%u", (unsigned) egid);
+      grp = getgrgid (egid);
+      if (grp == NULL)
+	problems++;
+      else
+	printf ("(%s)", grp->gr_name);
+    }
+
+#ifdef NGROUPS_MAX
+  {
+    int ngroups;
+    GETGROUPS_T *groups;
+    register int i;
+
+    groups = (GETGROUPS_T *) xmalloc (NGROUPS_MAX * sizeof (GETGROUPS_T));
+    if (username == 0)
+      ngroups = getgroups (NGROUPS_MAX, groups);
+    else
+      ngroups = getugroups (NGROUPS_MAX, groups, username);
+    if (ngroups < 0)
+      {
+	error (0, errno, "cannot get supplemental group list");
+	problems++;
+	free (groups);
+	return;
+      }
+
+    if (ngroups > 0)
+      fputs (" groups=", stdout);
+    for (i = 0; i < ngroups; i++)
+      {
+	if (i > 0)
+	  putchar (',');
+	printf ("%u", (unsigned) groups[i]);
+	grp = getgrgid (groups[i]);
+	if (grp == NULL)
+	  problems++;
+	else
+	  printf ("(%s)", grp->gr_name);
+      }
+    free (groups);
+  }
+#endif
+}
+
+void
+usage ()
+{
+  fprintf (stderr, "\
+Usage: %s [-gnruG] [--group] [--name] [--real] [--user] [--groups] [username]\n",
+	   program_name);
+  exit (1);
+}