gen/common/mntent.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 1990 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

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

#include <stdio.h>
#include <ctype.h>
#include <mntent.h>
#include <sys/file.h>
#include <malloc.h>

static int  mntprtent(FILE *, struct mntent *);

static  struct mntent *mntp;

struct mntent *
_mnt(void)
{

    if (mntp == 0)
        mntp = (struct mntent *)calloc(1, sizeof (struct mntent));
    return (mntp);
}

static char *
mntstr(char **p)
{
    unsigned char *cp = (unsigned char *) *p;
    unsigned char *retstr;

    while (*cp && isspace(*cp))
        cp++;
    retstr = cp;
    while (*cp && !isspace(*cp))
        cp++;
    if (*cp) {
        *cp = '\0';
        cp++;
    }
    *p = (char *) cp;
    return ((char *)retstr);
}

static int
mntdigit(char **p)
{
    int value = 0;
    unsigned char *cp = (unsigned char *) *p;

    while (*cp && isspace(*cp))
        cp++;
    for (; *cp && isdigit(*cp); cp++) {
        value *= 10;
        value += *cp - '0';
    }
    while (*cp && !isspace(*cp))
        cp++;
    if (*cp) {
        *cp = '\0';
        cp++;
    }
    *p =  (char *) cp;
    return (value);
}

static int
mnttabscan(FILE *mnttabp, struct mntent *mnt)
{
    static  char *line = NULL;
    char *cp;

    if (line == NULL)
        line = (char *)malloc(BUFSIZ+1);
    do {
        cp = fgets(line, BUFSIZ, mnttabp);
        if (cp == NULL) {
            return (EOF);
        }
    } while (*cp == '#');
    mnt->mnt_fsname = mntstr(&cp);
    if (*cp == '\0')
        return (1);
    mnt->mnt_dir = mntstr(&cp);
    if (*cp == '\0')
        return (2);
    mnt->mnt_type = mntstr(&cp);
    if (*cp == '\0')
        return (3);
    mnt->mnt_opts = mntstr(&cp);
    if (*cp == '\0')
        return (4);
    mnt->mnt_freq = mntdigit(&cp);
    if (*cp == '\0')
        return (5);
    mnt->mnt_passno = mntdigit(&cp);
    return (6);
}

FILE *
setmntent(char *fname, char *flag)
{
    FILE *mnttabp;

    if ((mnttabp = fopen(fname, flag)) == NULL) {
        return (NULL);
    }
    for (; *flag ; flag++) {
        if (*flag == 'w' || *flag == 'a' || *flag == '+') {
            if (flock(fileno(mnttabp), LOCK_EX) < 0) {
                fclose(mnttabp);
                return (NULL);
            }
            break;
        }
    }
    return (mnttabp);
}

int
endmntent(FILE *mnttabp)
{

    if (mnttabp) {
        fclose(mnttabp);
    }
    return (1);
}

struct mntent *
getmntent(FILE *mnttabp)
{
    int nfields;

    if (mnttabp == 0)
        return ((struct mntent *)0);
    if (_mnt() == 0)
        return ((struct mntent *)0);
    nfields = mnttabscan(mnttabp, mntp);
    if (nfields == EOF || nfields != 6)
        return ((struct mntent *)0);
    return (mntp);
}

int
addmntent(FILE *mnttabp, struct mntent *mnt)
{
    if (fseek(mnttabp, 0L, 2) < 0)
        return (1);
    if (mnt == (struct mntent *)0)
        return (1);
    if (mnt->mnt_fsname == NULL || mnt->mnt_dir  == NULL ||
        mnt->mnt_type   == NULL || mnt->mnt_opts == NULL)
        return (1);

    mntprtent(mnttabp, mnt);
    return (0);
}

static char *
mntopt(char **p)
{
    unsigned char *cp = (unsigned char *) *p;
    unsigned char *retstr;

    while (*cp && isspace(*cp))
        cp++;
    retstr = cp;
    while (*cp && *cp != ',')
        cp++;
    if (*cp) {
        *cp = '\0';
        cp++;
    }
    *p =  (char *) cp;
    return ((char *)retstr);
}

char *
hasmntopt(struct mntent *mnt, char *opt)
{
    char *f, *opts;
    static char *tmpopts;

    if (tmpopts == 0) {
        tmpopts = (char *)calloc(256, sizeof (char));
        if (tmpopts == 0)
            return (0);
    }
    strcpy(tmpopts, mnt->mnt_opts);
    opts = tmpopts;
    f = mntopt(&opts);
    for (; *f; f = mntopt(&opts)) {
        if (strncmp(opt, f, strlen(opt)) == 0)
            return (f - tmpopts + mnt->mnt_opts);
    }
    return (NULL);
}

static int
mntprtent(FILE *mnttabp, struct mntent *mnt)
{
    fprintf(mnttabp, "%s %s %s %s %d %d\n",
        mnt->mnt_fsname,
        mnt->mnt_dir,
        mnt->mnt_type,
        mnt->mnt_opts,
        mnt->mnt_freq,
        mnt->mnt_passno);
    return (0);
}