lib/users/loadpri.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*    All Rights Reserved   */

#pragma ident   "%Z%%M% %I% %E% SMI"

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

# include   "lp.h"
# include   "users.h"

static long pri;

/*
  Input:  Path name of the user priority file.  It has the following
        format:
    1 line with a number representing the default priority level.
        This must be the first line of the file, and no extra
        white space is allowed between the priority value and
        the newline.
    1 line anywhere in the file with a number representing
        the default priority limit.  This number is followed
        by a ':', and no extra white space is allowed.
    any number of lines with a number followed by a ':', followed
        by a white space (blank, tab or newline) separated
        list of user names.  No white space is allowed
        between the priority value and the colon (:), but any
        amount is ok in the UID list.

  Note:  If the default priority level is missing, a value of 20 will
    be used.  If the default limit is missing, zero will be used.
    Also, the st_priority_file writes out the priority file in the
    same order as the fields occur in the user_priority structure,
    but the only order restriction is that the default level is
    the first this.  A priority level may occur more than once, and
    this function will group them together (but the defaults may
    only occur once, however the defaults may occur only once each.

  Output:  This function returns a pointer to a statically stored
    structure containing the priority information.

   Effect:  The user priority file is read and parsed.  Storage for
    the priorities are allocated and loaded.  In case of an error,
    it prints out an error message, and returns 0 (NULL).
*/

struct user_priority * ld_priority_file ( char * path )
{
    char                line[BUFSIZ],
                    *p,
                    *user,
                    *next_user();
    static struct user_priority     pri_tbl;
    int                 line_no = 1,
                        opri;
    int fd;

    if ((fd = open_locked(path, "r", 0)) < 0) {
    if (errno == ENOENT) {
empty:
        pri_tbl.deflt = LEVEL_DFLT;
        pri_tbl.deflt_limit = LIMIT_DFLT;
        memset ((char *)pri_tbl.users, 0, sizeof(pri_tbl.users));
        return (&pri_tbl);
    }
    return(0);
    }

    /* initialize table to empty */
    pri_tbl.deflt = -1;
    pri_tbl.deflt_limit = -1;
    memset ((char *)pri_tbl.users, 0, sizeof(pri_tbl.users));

    /* this loop reads the line containing the default priority,
       if any, and the first priority limit.  p is left pointing
       to the colon (:) in the line with the first limit. */

    while (1)
    {
    if (!(p = fdgets(line, BUFSIZ, fd)))
        goto empty;
    p = line;
    pri = strtol(line, &p, 10);
    if (p == line)
        goto Error;
    if (pri < PRI_MIN || pri > PRI_MAX)
        goto Error;
    if (line_no == 1 && *p == '\n' && !p[1])
        pri_tbl.deflt = pri;
    else
        if (*p == ':')
        {
        p++;
        break;
        }
        else
        goto Error;
    line_no++;
    }

    do
    {
    /* search list for this priority */
    opri = pri;
    if (!(user = next_user(fd, line, &p)))
    {
        if (pri_tbl.deflt_limit == -1)
        {
        pri_tbl.deflt_limit = opri;
        if (pri == -1) break;
        if (!(user = next_user(fd, line, &p))) goto Error;
        }
        else
        {
Error:
            errno = EBADF;
        close(fd);
        return(0);
        }
    }

    do
    {
        add_user (&pri_tbl, user, pri);
    }
    while ((user = next_user(fd, line, &p)));
    }
    while (pri != -1);

    if (pri_tbl.deflt == -1)
    pri_tbl.deflt = LEVEL_DFLT;

    if (pri_tbl.deflt_limit == -1)
    pri_tbl.deflt_limit = LIMIT_DFLT;

    close(fd);
    return (&pri_tbl);
}

/*
Inputs:  A pointer to a limit structure, and a user.
Ouputs:  The limit structure is modified.
Effects: Adds <user> to the list of users, if it is not already
     there.
*/

int add_user ( struct user_priority * ppri_tbl, char * user, int limit )
{
    if (limit < PRI_MIN || PRI_MAX < limit)
    return 1;
    addlist (&(ppri_tbl->users[limit - PRI_MIN]), user);
    return 0;
}

/*
Inputs:   The input file to read additional lines, a pointer to
      a buffer containing the current line, and to read additional
      lines into, and a pointer to the location pointer (a pointer
      into buf).
Outputs:  The routine returns the next user-id read or 0 if all the
      users for this priority are read.  The buffer, the location
      pointer, and the variable pri are modified as a side effect.
Effects:  The input buffer is scanned starting at *pp for the next
      user-id, if the end of the line is reached, the next line is
      read from the file.  If it scans the next priority value, the
      variable pri (static to this file), is set to that priority.
      EOF is indicated by setting this variable to -1, and also
      returning 0.
*/
char * next_user (int fd, char * buf, char ** pp )
{
    long    temp;
    char    *p;
    static  int beg_line = 0; /* assumes a partial line is in buf to start */

    do
    {
    while (**pp == ' ' || **pp == '\n' || **pp == '\t')
        (*pp)++;
    p = *pp;
    if (*p)
    {
        if (*p >= '0' && *p <= '9')
        {
        temp = strtol(p, pp, 10);
        if (beg_line && **pp == ':')
        {
            (*pp)++;
            pri = temp;
            beg_line = 0;
            return (0);
        }
        }

        for (; **pp && **pp != ' ' && **pp != '\n' && **pp != '\t'; (*pp)++)
        ;
        if (**pp)
        *(*pp)++ = 0;
        beg_line = 0;
        return (p);
    }
    beg_line = 1;
    }
    while (*pp = fdgets(buf, BUFSIZ, fd));

    pri = -1;
    return (0);
}

/*
Inputs:  A pointer to a priority table and a user.
Outputs: Zero if user found, else 1, and priority table is modified.
Effects: All occurences of <user> in the priority table will be removed.
     (There should only be one at most.)
*/
int del_user ( struct user_priority * ppri_tbl, char * user )
{
    int     limit;

    for (limit = PRI_MIN; limit <= PRI_MAX; limit++)
    if (searchlist(user, ppri_tbl->users[limit - PRI_MIN]))
    {
        dellist (&(ppri_tbl->users[limit - PRI_MIN]), user);
        return (0);
    }
    return (1);
}