/*
 * 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 (c) 2000 by Sun Microsystems, Inc.
 * All rights reserved.
 */

#include <sys/types.h>
#include <sys/statvfs.h>
#include <sys/param.h>
#include <sys/stat.h>

#include <unistd.h>
#include <string.h>
#include <stdio.h>
#include <fcntl.h>

#include "utils.h"

static FILE *
minfree_open(const char *dir, int oflags, const char *fmode)
{
        char path[MAXPATHLEN];
        int fd;

        (void) snprintf(path, sizeof (path), "%s/minfree", dir);

        if ((fd = open(path, oflags, S_IRUSR | S_IWUSR)) >= 0)
                return (fdopen(fd, fmode));

        return (NULL);
}

int
minfree_read(const char *dir, unsigned long long *ullp)
{
        FILE *fp = minfree_open(dir, O_RDONLY, "r");

        if (fp != NULL) {
                char buf[BUFSIZ];
                int status = -1;

                if (fgets(buf, BUFSIZ, fp) != NULL) {
                        if (valid_str2ull(buf, ullp))
                                status = 0;
                        else
                                warn(gettext("\"%s/minfree\": invalid minfree "
                                    "value -- %s\n"), dir, buf);
                }

                (void) fclose(fp);
                return (status);
        }

        return (-1);
}

int
minfree_write(const char *dir, unsigned long long ull)
{
        FILE *fp = minfree_open(dir, O_WRONLY | O_CREAT | O_TRUNC, "w");

        if (fp != NULL) {
                int status = fprintf(fp, "%llu\n", ull);
                (void) fclose(fp);
                return (status);
        }

        return (-1);
}

int
minfree_compute(const char *dir, char *s, unsigned long long *ullp)
{
        size_t len = strlen(s);
        unsigned long long m = 1;

        struct statvfs64 fsb;
        int pct;

        switch (s[len - 1]) {
        case '%':
                s[len - 1] = '\0';

                if (!valid_str2int(s, &pct) || pct > 100) {
                        warn(gettext("invalid minfree %% -- %s\n"), s);
                        return (-1);
                }

                if (statvfs64(dir, &fsb) == -1) {
                        warn(gettext("failed to statvfs %s"), dir);
                        return (-1);
                }

                *ullp = fsb.f_blocks * fsb.f_frsize *
                    (u_longlong_t)pct / 100ULL / 1024ULL;

                return (0);

        case 'm':
        case 'M':
                m = 1024ULL;
                /*FALLTHRU*/

        case 'k':
        case 'K':
                s[len - 1] = '\0';

                if (valid_str2ull(s, ullp)) {
                        *ullp *= m;
                        return (0);
                }

                warn(gettext("invalid minfree value -- %s\n"), s);
                return (-1);

        default:
                warn(gettext("expected m, k, or %% unit after "
                    "minfree -- %s\n"), s);
                return (-1);
        }
}