[become] / src / name.c

/* -*-c-*-
 *
 * $Id: name.c,v 1.2 1997/08/04 10:24:24 mdw Exp $
 *
 * Looking up of names in symbol tables
 *
 * (c) 1997 EBI
 */

/*----- Licensing notice --------------------------------------------------*
 *
 * This file is part of `become'
 *
 * `Become' 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 of the License, or
 * (at your option) any later version.
 *
 * `Become' 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 `become'; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*----- Revision history --------------------------------------------------*
 *
 * $Log: name.c,v $
 * Revision 1.2  1997/08/04 10:24:24  mdw
 * Sources placed under CVS control.
 *
 * Revision 1.1  1997/07/21  13:47:46  mdw
 * Initial revision
 *
 */

/*----- Header files ------------------------------------------------------*/

/* --- ANSI headers --- */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/* --- Unix headers --- */

#include "config.h"

#ifdef HAVE_YP
#  include <rpcsvc/ypclnt.h>
#  include <rpcsvc/yp_prot.h>
#endif

#include <grp.h>
#include <pwd.h>

/* --- Local headers --- */

#include "become.h"
#include "class.h"
#include "name.h"
#include "sym.h"
#include "userdb.h"
#include "utils.h"

/*----- Static variables --------------------------------------------------*/

static sym_table name__table;           /* Symbol table for everything */

/*----- Main code ---------------------------------------------------------*/

/* --- @name__users@ --- *
 *
 * Arguments:   ---
 *
 * Returns:     ---
 *
 * Use:         Adds all of the users registered with the user database to
 *              the name table.  Also adds the users' primary groups.
 */

static void name__users(void)
{
  struct passwd *pw;
  struct group *gr;

  userdb_iterateUsers();
  while ((pw = userdb_nextUser()) != 0) {
    unsigned f;
    name *n;
    int u;

    /* --- First, add the user to the table --- */

    n = sym_find(&name__table, pw->pw_name, -1, sizeof(name), &f);
    if (!f) {
      sym_table *t = xmalloc(sizeof(*t));
      sym_createTable(t);
      n->c = class_create(clType_user, t);
    }
    u = pw->pw_uid;
    sym_find(n->c->t, (char *)&u, sizeof(u), sizeof(sym_base), 0);

    /* --- Now handle the user's default group --- */

    if ((gr = userdb_groupById(pw->pw_gid)) != 0) {
      n = sym_find(&name__table, gr->gr_name, -1, sizeof(name), &f);
      if (!f) {
        sym_table *t = xmalloc(sizeof(*t));
        sym_createTable(t);
        n->c = class_create(clType_user, t);
      }
      sym_find(n->c->t, (char *)&u, sizeof(u), sizeof(sym_base), 0);
    }
  }
}

/* --- @name__groups@ --- *
 *
 * Arguments:   ---
 *
 * Returns:     ---
 *
 * Use:         Adds users into all of their supplementary groups.
 */

static void name__groups(void)
{
  struct group *gr;
  struct passwd *pw;
  char **p;

  userdb_iterateGroups();
  while ((gr = userdb_nextGroup()) != 0) {
    unsigned f;
    name *n;
    int u;

    /* --- Add the group name to the table --- */

    n = sym_find(&name__table, gr->gr_name, -1, sizeof(name), &f);
    if (!f) {
      sym_table *t = xmalloc(sizeof(*t));
      sym_createTable(t);
      n->c = class_create(clType_user, t);
    }

    /* --- Now add all of the members --- */

    for (p = gr->gr_mem; *p; p++) {
      if ((pw = userdb_userByName(*p)) != 0) {
        u = pw->pw_uid;
        sym_find(n->c->t, (char *)&u, sizeof(u), sizeof(sym_base), 0);
      }
    }
  }
}

/* --- @name_init@ --- *
 *
 * Arguments:   ---
 *
 * Returns:     ---
 *
 * Use:         Initialises the name table.  Requires the user database to
 *              be populated (see @userdb_local@ and @userdb_yp@).
 */

void name_init(void)
{
  /* --- Initialise the name table --- */

  sym_createTable(&name__table);

  /* --- Add everyone into the table --- */

  name__users();
  name__groups();

  /* --- Finally add in the `all' class --- *
   *
   * Do that now, to prevent it being overwritten by the above.
   */

  {
    name *n;
    unsigned f;

    n = sym_find(&name__table, "all", -1, sizeof(name), &f);
    if (f)
      class_dec(n->c);
    n->c = class_all;
  }
}

/* --- @name_reinit@ --- *
 *
 * Arguments:   ---
 *
 * Returns:     ---
 *
 * Use:         Reinitialises the names table.  It's cleared and then
 *              initialised with the current user and group ids as for
 *              @name_init@ above.
 */

void name_reinit(void)
{
  /* --- Empty the symbol table --- */

  {
    sym_iter i;
    name *n;

    for (sym_createIter(&i, &name__table); (n = sym_next(&i)) != 0; ) {
      if (n->c)
        class_dec(n->c);
    }
  }

  /* --- Destroy and recreate the table --- */

  sym_destroyTable(&name__table);
  name_init();
}

/* --- @name_find@ --- *
 *
 * Arguments:   @const char *p@ = pointer to name to look up
 *              @unsigned create@ = whether to create the item
 *              @unsigned *f@ = whether the item was created
 *
 * Returns:     Pointer to a @name@ block containing the symbol, or
 *              zero if it wasn't found and we didn't want to create a
 *              new one.
 *
 * Use:         Looks up a name in the symbol table and returns the
 *              item so located.
 */

name *name_find(const char *p, unsigned create, unsigned *f)
{
  /* --- This is a trivial veneer onto @sym_find@ --- */

  return (sym_find(&name__table, p, -1, create ? sizeof(name) : 0, f));
}

/* --- @name_dump@ --- *
 *
 * Arguments:   ---
 *
 * Returns:     ---
 *
 * Use:         Dumps a complete listing of the symbol table.
 */

void name_dump(void)
{
  sym_iter i;
  name *n;

  trace(TRACE_DEBUG, "name: dumping names");
  for (sym_createIter(&i, &name__table); (n = sym_next(&i)) != 0; ) {
    trace(TRACE_DEBUG, "name: dumping `%s'", n->base.name);
    class_dump(n->c);
  }
}  

/*----- Test driver -------------------------------------------------------*/

#ifdef TEST_RIG

int main(void)
{
  userdb_init();
  userdb_local();
  userdb_yp();
  ego("name-test");
  traceon(stdout, TRACE_DEBUG);
  name_init();
  name_dump();
  return (0);
}

#endif