source: trunk/third/ispell/xgets.c @ 10334

#ifndef lint
static char Rcs_Id[] =
    "$Id: xgets.c,v 1.1.1.1 1997-09-03 21:08:10 ghudson Exp $";
#endif

/*
 * Copyright 1987, 1988, 1989, 1992, 1993, Geoff Kuenning, Granada Hills, CA
 * 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. All modifications to the source code must be clearly marked as
 *    such.  Binary redistributions based on modified source code
 *    must be clearly marked as modified versions in the documentation
 *    and/or other materials provided with the distribution.
 * 4. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgment:
 *      This product includes software developed by Geoff Kuenning and
 *      other unpaid contributors.
 * 5. The name of Geoff Kuenning may not be used to endorse or promote
 *    products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY GEOFF KUENNING 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 GEOFF KUENNING 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.
 */

/*
 * $Log: not supported by cvs2svn $
 * Revision 1.22  1994/09/16  04:48:34  geoff
 * Be sure to deliver newlines to the caller, so that it can tell whether
 * or not a complete line was read.
 *
 * Revision 1.21  1994/01/25  07:12:22  geoff
 * Get rid of all old RCS log lines in preparation for the 3.1 release.
 *
 */

#include "config.h"
#include "ispell.h"
#include "proto.h"

char *          xgets P ((char * string, int size, FILE * stream));

#ifndef MAXINCLUDEFILES
#define MAXINCLUDEFILES 1       /* maximum number of new files in stack */
#endif

/*
 * xgets () acts just like gets () except that if a line matches
 * "&Include_File&<something>" xgets () will start reading from the
 * file <something>.
 *
 *  Andrew Vignaux -- andrew@vuwcomp  Fri May  8 16:40:23 NZST 1987
 * modified
 *  Mark Davies -- mark@vuwcomp  Mon May 11 22:38:10 NZST 1987
 */

char * xgets (str, size, stream)
    char                str[];
    int                 size;
    FILE *              stream;
    {
#if MAXINCLUDEFILES == 0
    return fgets (str, size, stream);
#else
    static char *       Include_File = DEFINCSTR;
    static int          Include_Len = 0;
    static FILE *       F[MAXINCLUDEFILES+1];
    static FILE **      current_F = F;
    char *              s = str;
    int                 c;

    /* read the environment variable if we havent already */
    if (Include_Len == 0)
        {
        char *          env_variable;

        if ((env_variable = getenv (INCSTRVAR)) != NULL)
            Include_File = env_variable;
        Include_Len = strlen (Include_File);

        /* initialise the file stack */
        *current_F = stream;
        }

    for (  ;  ;  )
        {
        c = '\0';
        if ((s - str) + 1 < size
          &&  (c = getc (*current_F)) != EOF)
            {
            *s++ = (char) c;
            if (c != '\n')
                continue;
            }
        *s = '\0';              /* end of line */
        if (c == EOF)
            {
            if (current_F == F) /* if end of standard input */
                {
                if (s == str)
                    return (NULL);
                }
            else
                {
                (void) fclose (*(current_F--));
                if (s == str) continue;
                }
            }

        if (incfileflag != 0
          &&  strncmp (str, Include_File, (unsigned int) Include_Len) == 0)
            {
            char *      file_name = str + Include_Len;

            if (current_F - F < MAXINCLUDEFILES  &&  strlen (file_name) != 0)
                {
                FILE *  f;

                if (f = fopen (file_name, "r"))
                    *(++current_F) = f;
                }
            s = str;
            continue;
            }
        break;
        }
    
    return (str);
#endif
    }