/*
 * lsvfs - list loaded VFSes
 * Garrett A. Wollman, September 1994
 * This file is in the public domain.
 *
 */

#include <sys/capsicum.h>
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/sysctl.h>

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

#define FMT     "%-32.32s 0x%08x %5d  %s\n"
#define HDRFMT  "%-32.32s %10s %5.5s  %s\n"
#define DASHES  "-------------------------------- "     \
                "---------- -----  ---------------\n"

static struct flaglist {
        int             flag;
        const char      str[32]; /* must be longer than the longest one. */
} fl[] = {
        { .flag = VFCF_STATIC, .str = "static", },
        { .flag = VFCF_NETWORK, .str = "network", },
        { .flag = VFCF_READONLY, .str = "read-only", },
        { .flag = VFCF_SYNTHETIC, .str = "synthetic", },
        { .flag = VFCF_LOOPBACK, .str = "loopback", },
        { .flag = VFCF_UNICODE, .str = "unicode", },
        { .flag = VFCF_JAIL, .str = "jail", },
        { .flag = VFCF_DELEGADMIN, .str = "delegated-administration", },
};

static const char *fmt_flags(int);

int
main(int argc, char **argv)
{
        struct xvfsconf *xvfsp;
        size_t cnt, buflen;
        int rv = 0;

        argc--, argv++;

        if (sysctlbyname("vfs.conflist", NULL, &buflen, NULL, 0) < 0)
                err(EXIT_FAILURE, "sysctl(vfs.conflist)");
        if ((xvfsp = malloc(buflen)) == NULL)
                errx(EXIT_FAILURE, "malloc failed");
        if (sysctlbyname("vfs.conflist", xvfsp, &buflen, NULL, 0) < 0)
                err(EXIT_FAILURE, "sysctl(vfs.conflist)");
        cnt = buflen / sizeof(struct xvfsconf);

        caph_cache_catpages();
        if (caph_enter() != 0)
                err(EXIT_FAILURE, "failed to enter capability mode");

        printf(HDRFMT, "Filesystem", "Num", "Refs", "Flags");
        fputs(DASHES, stdout);

        for (size_t i = 0; i < cnt; i++) {
                if (argc > 0) {
                        int j;
                        for (j = 0; j < argc; j++) {
                                if (strcmp(argv[j], xvfsp[i].vfc_name) == 0)
                                        break;
                        }
                        if (j == argc)
                                continue;
                }

                printf(FMT, xvfsp[i].vfc_name, xvfsp[i].vfc_typenum,
                    xvfsp[i].vfc_refcount, fmt_flags(xvfsp[i].vfc_flags));
        }
        free(xvfsp);

        return (rv);
}

static const char *
fmt_flags(int flags)
{
        static char buf[sizeof(struct flaglist) * sizeof(fl)];

        buf[0] = '\0';
        for (size_t i = 0; i < (int)nitems(fl); i++) {
                if ((flags & fl[i].flag) != 0) {
                        strlcat(buf, fl[i].str, sizeof(buf));
                        strlcat(buf, ", ", sizeof(buf));
                }
        }

        /* Zap the trailing comma + space. */
        if (buf[0] != '\0')
                buf[strlen(buf) - 2] = '\0';
        return (buf);
}