source: branches/samba-3.3.x/source/printing/pcap.c

/* 
   Unix SMB/CIFS implementation.
   printcap parsing
   Copyright (C) Karl Auer 1993-1998

   Re-working by Martin Kiff, 1994
   
   Re-written again by Andrew Tridgell

   Modified for SVID support by Norm Jacobs, 1997

   Modified for CUPS support by Michael Sweet, 1999
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

/*
 *  This module contains code to parse and cache printcap data, possibly
 *  in concert with the CUPS/SYSV/AIX-specific code found elsewhere.
 *
 *  The way this module looks at the printcap file is very simplistic.
 *  Only the local printcap file is inspected (no searching of NIS
 *  databases etc).
 *
 *  There are assumed to be one or more printer names per record, held
 *  as a set of sub-fields separated by vertical bar symbols ('|') in the
 *  first field of the record. The field separator is assumed to be a colon
 *  ':' and the record separator a newline.
 * 
 *  Lines ending with a backspace '\' are assumed to flag that the following
 *  line is a continuation line so that a set of lines can be read as one
 *  printcap entry.
 *
 *  A line stating with a hash '#' is assumed to be a comment and is ignored
 *  Comments are discarded before the record is strung together from the
 *  set of continuation lines.
 *
 *  Opening a pipe for "lpc status" and reading that would probably 
 *  be pretty effective. Code to do this already exists in the freely
 *  distributable PCNFS server code.
 *
 *  Modified to call SVID/XPG4 support if printcap name is set to "lpstat"
 *  in smb.conf under Solaris.
 *
 *  Modified to call CUPS support if printcap name is set to "cups"
 *  in smb.conf.
 *
 *  Modified to call iPrint support if printcap name is set to "iprint"
 *  in smb.conf.
 */

#include "includes.h"


struct pcap_cache {
        char *name;
        char *comment;
        struct pcap_cache *next;
};

/* The systemwide printcap cache. */
static struct pcap_cache *pcap_cache = NULL;

bool pcap_cache_add_specific(struct pcap_cache **ppcache, const char *name, const char *comment)
{
        struct pcap_cache *p;

        if (name == NULL || ((p = SMB_MALLOC_P(struct pcap_cache)) == NULL))
                return false;

        p->name = SMB_STRDUP(name);
        p->comment = (comment && *comment) ? SMB_STRDUP(comment) : NULL;

        DEBUG(11,("pcap_cache_add_specific: Adding name %s info %s\n",
                p->name, p->comment ? p->comment : ""));

        p->next = *ppcache;
        *ppcache = p;

        return true;
}

void pcap_cache_destroy_specific(struct pcap_cache **pp_cache)
{
        struct pcap_cache *p, *next;

        for (p = *pp_cache; p != NULL; p = next) {
                next = p->next;

                SAFE_FREE(p->name);
                SAFE_FREE(p->comment);
                SAFE_FREE(p);
        }
        *pp_cache = NULL;
}

bool pcap_cache_add(const char *name, const char *comment)
{
        return pcap_cache_add_specific(&pcap_cache, name, comment);
}

bool pcap_cache_loaded(void)
{
        return (pcap_cache != NULL);
}

void pcap_cache_replace(const struct pcap_cache *pcache)
{
        const struct pcap_cache *p;

        pcap_cache_destroy_specific(&pcap_cache);
        for (p = pcache; p; p = p->next) {
                pcap_cache_add(p->name, p->comment);
        }
}

void pcap_cache_reload(void)
{
        const char *pcap_name = lp_printcapname();
        bool pcap_reloaded = False;
        struct pcap_cache *tmp_cache = NULL;
        XFILE *pcap_file;
        char *pcap_line;

        DEBUG(3, ("reloading printcap cache\n"));

        /* only go looking if no printcap name supplied */
        if (pcap_name == NULL || *pcap_name == 0) {
                DEBUG(0, ("No printcap file name configured!\n"));
                return;
        }

        tmp_cache = pcap_cache;
        pcap_cache = NULL;

#ifdef HAVE_CUPS
        if (strequal(pcap_name, "cups")) {
                pcap_reloaded = cups_cache_reload();
                goto done;
        }
#endif

#ifdef HAVE_IPRINT
        if (strequal(pcap_name, "iprint")) {
                pcap_reloaded = iprint_cache_reload();
                goto done;
        }
#endif

#if defined(SYSV) || defined(HPUX)
        if (strequal(pcap_name, "lpstat")) {
                pcap_reloaded = sysv_cache_reload();
                goto done;
        }
#endif

#ifdef AIX
        if (strstr_m(pcap_name, "/qconfig") != NULL) {
                pcap_reloaded = aix_cache_reload();
                goto done;
        }
#endif

        /* handle standard printcap - moved from pcap_printer_fn() */

        if ((pcap_file = x_fopen(pcap_name, O_RDONLY, 0)) == NULL) {
                DEBUG(0, ("Unable to open printcap file %s for read!\n", pcap_name));
                goto done;
        }

        for (; (pcap_line = fgets_slash(NULL, 1024, pcap_file)) != NULL; safe_free(pcap_line)) {
                char name[MAXPRINTERLEN+1];
                char comment[62];
                char *p, *q;

                if (*pcap_line == '#' || *pcap_line == 0)
                        continue;

                /* now we have a real printer line - cut at the first : */      
                if ((p = strchr_m(pcap_line, ':')) != NULL)
                        *p = 0;
      
                /*
                 * now find the most likely printer name and comment 
                 * this is pure guesswork, but it's better than nothing
                 */
                for (*name = *comment = 0, p = pcap_line; p != NULL; p = q) {
                        bool has_punctuation;

                        if ((q = strchr_m(p, '|')) != NULL)
                                *q++ = 0;

                        has_punctuation = (strchr_m(p, ' ') ||
                                           strchr_m(p, '\t') ||
                                           strchr_m(p, '(') ||
                                           strchr_m(p, ')'));

                        if (strlen(p) > strlen(comment) && has_punctuation) {
                                strlcpy(comment, p, sizeof(comment));
                                continue;
                        }

                        if (strlen(p) <= MAXPRINTERLEN &&
                            strlen(p) > strlen(name) && !has_punctuation) {
                                if (!*comment) {
                                        strlcpy(comment, name, sizeof(comment));
                                }
                                strlcpy(name, p, sizeof(name));
                                continue;
                        }

                        if (!strchr_m(comment, ' ') &&
                            strlen(p) > strlen(comment)) {
                                strlcpy(comment, p, sizeof(comment));
                                continue;
                        }
                }

                comment[60] = 0;
                name[MAXPRINTERLEN] = 0;

                if (*name && !pcap_cache_add(name, comment)) {
                        x_fclose(pcap_file);
                        goto done;
                }
        }

        x_fclose(pcap_file);
        pcap_reloaded = True;

done:
        DEBUG(3, ("reload status: %s\n", (pcap_reloaded) ? "ok" : "error"));

        if (pcap_reloaded)
                pcap_cache_destroy_specific(&tmp_cache);
        else {
                pcap_cache_destroy_specific(&pcap_cache);
                pcap_cache = tmp_cache;
        }

        return;
}


bool pcap_printername_ok(const char *printername)
{
        struct pcap_cache *p;

        for (p = pcap_cache; p != NULL; p = p->next)
                if (strequal(p->name, printername))
                        return True;

        return False;
}

/***************************************************************************
run a function on each printer name in the printcap file.
***************************************************************************/

void pcap_printer_fn_specific(const struct pcap_cache *pc,
                        void (*fn)(const char *, const char *, void *),
                        void *pdata)
{
        const struct pcap_cache *p;

        for (p = pc; p != NULL; p = p->next)
                fn(p->name, p->comment, pdata);

        return;
}

void pcap_printer_fn(void (*fn)(const char *, const char *, void *), void *pdata)
{
        pcap_printer_fn_specific(pcap_cache, fn, pdata);
}