/*
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS 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.
 *
 * @(#) Copyright (c) 1983, 1993 The Regents of the University of California.  All rights reserved.
 * @(#)recvjob.c        8.2 (Berkeley) 4/27/95
 * $FreeBSD: src/usr.sbin/lpr/lpd/recvjob.c,v 1.14.2.13 2002/06/19 01:46:48 gad Exp $
 * $DragonFly: src/usr.sbin/lpr/lpd/recvjob.c,v 1.4 2004/12/18 22:48:03 swildner Exp $
 */

/*
 * Receive printer jobs from the network, queue them and
 * start the printer daemon.
 */
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/stat.h>

#include <unistd.h>
#include <signal.h>
#include <fcntl.h>
#include <dirent.h>
#include <errno.h>
#include <syslog.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "lp.h"
#include "lp.local.h"
#include "ctlinfo.h"
#include "extern.h"
#include "pathnames.h"

#define ack()   write(STDOUT_FILENO, sp, (size_t)1);

static char      dfname[NAME_MAX];      /* data files */
static int       minfree;       /* keep at least minfree blocks available */
static const char       *sp = "";
static char      tfname[NAME_MAX];      /* tmp copy of cf before linking */

static int       chksize(int _size);
static void      frecverr(const char *_msg, ...) __printf0like(1, 2);
static int       noresponse(void);
static void      rcleanup(int _signo);
static int       read_number(const char *_fn);
static int       readfile(struct printer *_pp, char *_file, size_t _size);
static int       readjob(struct printer *_pp);


void
recvjob(const char *printer)
{
        struct stat stb;
        int status;
        struct printer myprinter, *pp = &myprinter;

        /*
         * Perform lookup for printer name or abbreviation
         */
        init_printer(pp);
        status = getprintcap(printer, pp);
        switch (status) {
        case PCAPERR_OSERR:
                frecverr("cannot open printer description file");
                break;
        case PCAPERR_NOTFOUND:
                frecverr("unknown printer %s", printer);
                break;
        case PCAPERR_TCLOOP:
                fatal(pp, "potential reference loop detected in printcap file");
        default:
                break;
        }
        
        close(2);                       /* set up log file */
        if (open(pp->log_file, O_WRONLY|O_APPEND, 0664) < 0) {
                syslog(LOG_ERR, "%s: %m", pp->log_file);
                open(_PATH_DEVNULL, O_WRONLY);
        }

        if (chdir(pp->spool_dir) < 0)
                frecverr("%s: chdir(%s): %s", pp->printer, pp->spool_dir,
                    strerror(errno));
        if (stat(pp->lock_file, &stb) == 0) {
                if (stb.st_mode & 010) {
                        /* queue is disabled */
                        putchar('\1');          /* return error code */
                        exit(1);
                }
        } else if (stat(pp->spool_dir, &stb) < 0)
                frecverr("%s: stat(%s): %s", pp->printer, pp->spool_dir,
                    strerror(errno));
        minfree = 2 * read_number("minfree");   /* scale KB to 512 blocks */
        signal(SIGTERM, rcleanup);
        signal(SIGPIPE, rcleanup);

        if (readjob(pp))
                printjob(pp);
}

/*
 * Read printer jobs sent by lpd and copy them to the spooling directory.
 * Return the number of jobs successfully transfered.
 */
static int
readjob(struct printer *pp)
{
        int size;
        int cfcnt, dfcnt;
        char *cp, *clastp, *errmsg;
        char givenid[32], givenhost[MAXHOSTNAMELEN];

        ack();
        cfcnt = 0;
        dfcnt = 0;
        for (;;) {
                /*
                 * Read a command to tell us what to do
                 */
                cp = line;
                clastp = line + sizeof(line) - 1;
                do {
                        size = read(STDOUT_FILENO, cp, (size_t)1);
                        if (size != (ssize_t)1) {
                                if (size < (ssize_t)0) {
                                        frecverr("%s: lost connection",
                                            pp->printer);
                                        /*NOTREACHED*/
                                }
                                return (cfcnt);
                        }
                } while ((*cp++ != '\n') && (cp <= clastp));
                if (cp > clastp) {
                        frecverr("%s: readjob overflow", pp->printer);
                        /*NOTREACHED*/
                }
                *--cp = '\0';
                cp = line;
                switch (*cp++) {
                case '\1':      /* cleanup because data sent was bad */
                        rcleanup(0);
                        continue;

                case '\2':      /* read cf file */
                        size = 0;
                        dfcnt = 0;
                        while (*cp >= '0' && *cp <= '9')
                                size = size * 10 + (*cp++ - '0');
                        if (*cp++ != ' ')
                                break;
                        /*
                         * host name has been authenticated, we use our
                         * view of the host name since we may be passed
                         * something different than what gethostbyaddr()
                         * returns
                         */
                        strlcpy(cp + 6, from_host, sizeof(line)
                            + (size_t)(line - cp - 6));
                        if (strchr(cp, '/')) {
                                frecverr("readjob: %s: illegal path name", cp);
                                /*NOTREACHED*/
                        }
                        strlcpy(tfname, cp, sizeof(tfname));
                        tfname[sizeof (tfname) - 1] = '\0';
                        tfname[0] = 't';
                        if (!chksize(size)) {
                                write(STDOUT_FILENO, "\2", (size_t)1);
                                continue;
                        }
                        if (!readfile(pp, tfname, (size_t)size)) {
                                rcleanup(0);
                                continue;
                        }
                        errmsg = ctl_renametf(pp->printer, tfname);
                        tfname[0] = '\0';
                        if (errmsg != NULL) {
                                frecverr("%s: %s", pp->printer, errmsg);
                                /*NOTREACHED*/
                        }
                        cfcnt++;
                        continue;

                case '\3':      /* read df file */
                        *givenid = '\0';
                        *givenhost = '\0';
                        size = 0;
                        while (*cp >= '0' && *cp <= '9')
                                size = size * 10 + (*cp++ - '0');
                        if (*cp++ != ' ')
                                break;
                        if (strchr(cp, '/')) {
                                frecverr("readjob: %s: illegal path name", cp);
                                /*NOTREACHED*/
                        }
                        if (!chksize(size)) {
                                write(STDOUT_FILENO, "\2", (size_t)1);
                                continue;
                        }
                        strlcpy(dfname, cp, sizeof(dfname));
                        dfcnt++;
                        trstat_init(pp, dfname, dfcnt);
                        readfile(pp, dfname, (size_t)size);
                        trstat_write(pp, TR_RECVING, (size_t)size, givenid,
                            from_host, givenhost);
                        continue;
                }
                frecverr("protocol screwup: %s", line);
                /*NOTREACHED*/
        }
}

/*
 * Read files send by lpd and copy them to the spooling directory.
 */
static int
readfile(struct printer *pp, char *file, size_t size)
{
        char *cp;
        char buf[BUFSIZ];
        size_t amt, i;
        int err, fd, j;

        fd = open(file, O_CREAT|O_EXCL|O_WRONLY, FILMOD);
        if (fd < 0) {
                frecverr("%s: readfile: error on open(%s): %s",
                         pp->printer, file, strerror(errno));
                /*NOTREACHED*/
        }
        ack();
        err = 0;
        for (i = 0; i < size; i += BUFSIZ) {
                amt = BUFSIZ;
                cp = buf;
                if (i + amt > size)
                        amt = size - i;
                do {
                        j = read(STDOUT_FILENO, cp, amt);
                        if (j <= 0) {
                                frecverr("%s: lost connection", pp->printer);
                                /*NOTREACHED*/
                        }
                        amt -= j;
                        cp += j;
                } while (amt > 0);
                amt = BUFSIZ;
                if (i + amt > size)
                        amt = size - i;
                if (write(fd, buf, amt) != (ssize_t)amt) {
                        err++;
                        break;
                }
        }
        close(fd);
        if (err) {
                frecverr("%s: write error on close(%s)", pp->printer, file);
                /*NOTREACHED*/
        }
        if (noresponse()) {             /* file sent had bad data in it */
                if (strchr(file, '/') == NULL)
                        unlink(file);
                return (0);
        }
        ack();
        return (1);
}

static int
noresponse(void)
{
        char resp;

        if (read(STDOUT_FILENO, &resp, (size_t)1) != 1) {
                frecverr("lost connection in noresponse()");
                /*NOTREACHED*/
        }
        if (resp == '\0')
                return(0);
        return(1);
}

/*
 * Check to see if there is enough space on the disk for size bytes.
 * 1 == OK, 0 == Not OK.
 */
static int
chksize(int size)
{
        int spacefree;
        struct statfs sfb;

        if (statfs(".", &sfb) < 0) {
                syslog(LOG_ERR, "%s: %m", "statfs(\".\")");
                return (1);
        }
        spacefree = sfb.f_bavail * (sfb.f_bsize / 512);
        size = (size + 511) / 512;
        if (minfree + size > spacefree)
                return(0);
        return(1);
}

static int
read_number(const char *fn)
{
        char lin[80];
        FILE *fp;

        if ((fp = fopen(fn, "r")) == NULL)
                return (0);
        if (fgets(lin, 80, fp) == NULL) {
                fclose(fp);
                return (0);
        }
        fclose(fp);
        return (atoi(lin));
}

/*
 * Remove all the files associated with the current job being transfered.
 */
static void
rcleanup(int signo __unused)
{
        if (tfname[0] && strchr(tfname, '/') == NULL)
                unlink(tfname);
        if (dfname[0] && strchr(dfname, '/') == NULL) {
                do {
                        do
                                unlink(dfname);
                        while (dfname[2]-- != 'A');
                        dfname[2] = 'z';
                } while (dfname[0]-- != 'd');
        }
        dfname[0] = '\0';
}

#include <stdarg.h>

static void
frecverr(const char *msg, ...)
{
        va_list ap;
        va_start(ap, msg);
        syslog(LOG_ERR, "Error receiving job from %s:", from_host);
        vsyslog(LOG_ERR, msg, ap);
        va_end(ap);
        /*
         * rcleanup is not called until AFTER logging the error message,
         * because rcleanup will zap some variables which may have been
         * supplied as parameters for that msg...
         */
        rcleanup(0);
        /* 
         * Add a minimal delay before returning the final error code to
         * the sending host.  This just in case that machine responds
         * this error by INSTANTLY retrying (and instantly re-failing...).
         * It would be stupid of the sending host to do that, but if there
         * was a broken implementation which did it, the result might be
         * obscure performance problems and a flood of syslog messages on
         * the receiving host.
         */ 
        sleep(2);               /* a paranoid throttling measure */
        putchar('\1');          /* return error code */
        exit(1);
}