/*
 * Copyright 1997 Massachusetts Institute of Technology
 *
 * Permission to use, copy, modify, and distribute this software and
 * its documentation for any purpose and without fee is hereby
 * granted, provided that both the above copyright notice and this
 * permission notice appear in all copies, that both the above
 * copyright notice and this permission notice appear in all
 * supporting documentation, and that the name of M.I.T. not be used
 * in advertising or publicity pertaining to distribution of the
 * software without specific, written prior permission.  M.I.T. makes
 * no representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied
 * warranty.
 * 
 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

static const char copyright[] =
        "Copyright (C) 1997, Massachusetts Institute of Technology\r\n";

#include "lp.cdefs.h"           /* A cross-platform version of <sys/cdefs.h> */
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/stat.h>

#include <err.h>
#include <errno.h>
#include <grp.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>

#include <sys/param.h>          /* needed for lp.h but not used here */
#include <dirent.h>             /* ditto */
#include "lp.h"
#include "lp.local.h"
#include "pathnames.h"
#include "skimprintcap.h"

static  void check_spool_dirs(void);
static  int interpret_error(const struct printer *pp, int error);
static  void make_spool_dir(const struct printer *pp);
static  void note_spool_dir(const struct printer *pp, const struct stat *st);
static  void usage(void) __dead2;

static  int problems;           /* number of problems encountered */

/*
 * chkprintcap - check the printcap file for syntactic and semantic errors
 * Returns the number of problems found.
 */
int
main(int argc, char **argv)
{
        struct skiminfo *skres;
        char *pcap_fname;
        int c, error, makedirs, more, queuecnt, verbosity;
        struct printer myprinter, *pp;

        makedirs = 0;
        queuecnt = 0;
        verbosity = 0;
        pcap_fname = NULL;
        pp = &myprinter;

        while ((c = getopt(argc, argv, "df:v")) != -1) {
                switch (c) {
                case 'd':
                        makedirs = 1;
                        break;

                case 'f':
                        pcap_fname = strdup(optarg);
                        setprintcap(pcap_fname);
                        break;

                case 'v':
                        verbosity++;
                        break;

                default:
                        usage();
                }
        }

        if (optind != argc)
                usage();

        if (pcap_fname == NULL)
                pcap_fname = strdup(_PATH_PRINTCAP);

        /*
         * Skim through the printcap file looking for simple user-mistakes
         * which will produce the wrong result for the user, but which may
         * be pretty hard for the user to notice.  Such user-mistakes will
         * only generate warning messages.  The (fatal-) problem count will
         * only be incremented if there is a system problem trying to read
         * the printcap file.
        */
        skres = skim_printcap(pcap_fname, verbosity);
        if (skres == NULL) {
                problems = 1;
                goto main_ret;
        } else if (skres->fatalerr) {
                problems = skres->fatalerr;
                goto main_ret;
        }

        /*
         * Now use the standard capability-db routines to check the values
         * in each of the queues defined in the printcap file.
        */
        more = firstprinter(pp, &error);
        if (interpret_error(pp, error) && more)
                goto next;

        while (more) {
                struct stat stab;

                queuecnt++;
                errno = 0;
                if (stat(pp->spool_dir, &stab) < 0) {
                        if (errno == ENOENT && makedirs) {
                                make_spool_dir(pp);
                        } else {
                                problems++;
                                warn("%s: %s", pp->printer, pp->spool_dir);
                        }
                } else {
                        note_spool_dir(pp, &stab);
                }

                /* Make other queue-specific validity checks here... */

next:
                more = nextprinter(pp, &error);
                if (interpret_error(pp, error) && more)
                        goto next;
        }

        check_spool_dirs();

        if (queuecnt != skres->entries) {
                warnx("WARNING: found %d entries when skimming %s,",
                    skres->entries, pcap_fname);
                warnx("WARNING:  but only found %d queues to process!",
                    queuecnt);
        }

main_ret:
        free(pcap_fname);
        return (problems);
}

/*
 * Interpret the error code.  Returns 1 if we should skip to the next
 * record (as this record is unlikely to make sense).  If the problem
 * is very severe, exit.  Otherwise, return zero.
 */
static int
interpret_error(const struct printer *pp, int error)
{
        switch(error) {
        case PCAPERR_OSERR:
                err(++problems, "reading printer database");
        case PCAPERR_TCLOOP:
                ++problems;
                warnx("%s: loop detected in tc= expansion", pp->printer);
                return 1;
        case PCAPERR_TCOPEN:
                warnx("%s: unresolved tc= expansion", pp->printer);
                return 1;
        case PCAPERR_SUCCESS:
                break;
        default:
                errx(++problems, "unknown printcap library error %d", error);
        }
        return 0;
}

/*
 * Keep the list of spool directories.  Note that we don't whine
 * until all spool directories are noted, so that all of the more serious
 * problems are noted first.  We keep the list sorted by st_dev and
 * st_ino, so that the problem spool directories can be noted in
 * a single loop.
 */
struct  dirlist {
        LIST_ENTRY(dirlist) link;
        struct stat stab;
        char *path;
        char *printer;
};

static  LIST_HEAD(, dirlist) dirlist;

static int
lessp(const struct dirlist *a, const struct dirlist *b)
{
        if (a->stab.st_dev == b->stab.st_dev)
                return a->stab.st_ino < b->stab.st_ino;
        return a->stab.st_dev < b->stab.st_dev;
}

static int
equal(const struct dirlist *a, const struct dirlist *b)
{
        return ((a->stab.st_dev == b->stab.st_dev)
                && (a->stab.st_ino == b->stab.st_ino));
}

static void
note_spool_dir(const struct printer *pp, const struct stat *st)
{
        struct dirlist *dp, *dp2, *last;

        dp = malloc(sizeof *dp);
        if (dp == NULL)
                err(++problems, "malloc(%lu)", (u_long)sizeof *dp);
        
        dp->stab = *st;
        dp->printer = strdup(pp->printer);
        if (dp->printer == 0)
                err(++problems, "malloc(%lu)", strlen(pp->printer) + 1UL);
        dp->path = strdup(pp->spool_dir);
        if (dp->path == 0)
                err(++problems, "malloc(%lu)", strlen(pp->spool_dir) + 1UL);
        
        last = NULL;
        LIST_FOREACH(dp2, &dirlist, link) {
                if(!lessp(dp, dp2))
                        break;
                last = dp2;
        }

        if (last) {
                LIST_INSERT_AFTER(last, dp, link);
        } else {
                LIST_INSERT_HEAD(&dirlist, dp, link);
        }
}

static void
check_spool_dirs(void)
{
        struct dirlist *dp, *dp2;

        for (dp = LIST_FIRST(&dirlist); dp; dp = dp2) {
                dp2 = LIST_NEXT(dp, link);

                if (dp2 != NULL && equal(dp, dp2)) {
                        ++problems;
                        if (strcmp(dp->path, dp2->path) == 0) {
                                warnx("%s and %s share the same spool, %s",
                                      dp->printer, dp2->printer, dp->path);
                        } else {
                                warnx("%s (%s) and %s (%s) are the same "
                                      "directory", dp->path, dp->printer,
                                      dp2->path, dp2->printer);
                        }
                        continue;
                }
                /* Should probably check owners and modes here. */
        }
}

#ifndef SPOOL_DIR_MODE
#define SPOOL_DIR_MODE  (S_IRUSR | S_IWUSR | S_IXUSR \
                         | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH)
#endif

static void
make_spool_dir(const struct printer *pp)
{
        char *sd = pp->spool_dir;
        struct group *gr;
        struct stat stab;

        if (mkdir(sd, S_IRUSR | S_IXUSR) < 0) {
                problems++;
                warn("%s: mkdir %s", pp->printer, sd);
                return;
        }
        gr = getgrnam("daemon");
        if (gr == NULL)
                errx(++problems, "cannot locate daemon group");

        if (chown(sd, pp->daemon_user, gr->gr_gid) < 0) {
                ++problems;
                warn("%s: cannot change ownership to %ld:%ld", sd,
                     (long)pp->daemon_user, (long)gr->gr_gid);
                return;
        }

        if (chmod(sd, SPOOL_DIR_MODE) < 0) {
                ++problems;
                warn("%s: cannot change mode to %lo", sd, (long)SPOOL_DIR_MODE);
                return;
        }
        if (stat(sd, &stab) < 0)
                err(++problems, "stat: %s", sd);

        note_spool_dir(pp, &stab);
}

static void
usage(void)
{
        fprintf(stderr, "usage:\n\tchkprintcap [-dv] [-f printcapfile]\n");
        exit(1);
}