contrib/zkt/strlist.c

/*****************************************************************
**
**  @(#) strlist.c (c) Mar 2005  Holger Zuleger
**
**  TODO:   Maybe we should use a special type for the list:
**      typedef struct { char cnt; char list[0+1]; } strlist__t;
**      This results in better type control of the function parameters
**
**  Copyright (c) Mar 2005, Holger Zuleger HZnet. All rights reserved.
**
**  This software is open source.
**
**  Redistribution and use in source and binary forms, with or without
**  modification, are permitted provided that the following conditions
**  are met:
**
**  Redistributions of source code must retain the above copyright notice,
**  this list of conditions and the following disclaimer.
**
**  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.
**
**  Neither the name of Holger Zuleger HZnet 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 COPYRIGHT HOLDERS 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.
**
*****************************************************************/

#ifdef TEST
# include <stdio.h>
#endif
#include <string.h>
#include <stdlib.h>
#include "strlist.h"


/*****************************************************************
**  prepstrlist (str, delim)
**  prepare a string with delimiters to a so called strlist.
**  'str' is a list of substrings delimeted by 'delim'
**  The # of strings is stored at the first byte of the allocated
**  memory. Every substring is stored as a '\0' terminated C-String.
**  The function returns a pointer to dynamic allocated memory
*****************************************************************/
char    *prepstrlist (const char *str, const char *delim)
{
    char    *p;
    char    *new;
    int len;
    int cnt;

    if ( str == NULL )
        return NULL;

    len = strlen (str);
    if ( (new = malloc (len + 2)) == NULL )
        return new;

    cnt = 0;
    p = new;
    for ( *p++ = '\0'; *str; str++ )
    {
        if ( strchr (delim, *str) == NULL )
            *p++ = *str;
        else if ( p[-1] != '\0' )
        {
            *p++ = '\0';
            cnt++;
        }
    }
    *p = '\0';  /*terminate string */
    if ( p[-1] != '\0' )
        cnt++;
    *new = cnt & 0xFF;

    return new;
}

/*****************************************************************
**  isinlist (str, list)
**  check if 'list' contains 'str'
*****************************************************************/
int isinlist (const char *str, const char *list)
{
    int cnt;

    if ( list == NULL || *list == '\0' )
        return 1;
    if ( str == NULL || *str == '\0' )
        return 0;

    cnt = *list;
    while ( cnt-- > 0 )
    {
        list++;
        if ( strcmp (str, list) == 0 )
            return 1;
        list += strlen (list);
    }

    return 0;
}

/*****************************************************************
**  unprepstrlist (list, delimc)
*****************************************************************/
char    *unprepstrlist (char *list, char delimc)
{
    char    *p;
    int cnt;

    cnt = *list & 0xFF;
    p = list;
    for ( *p++ = delimc; cnt > 1; p++ )
        if ( *p == '\0' )
        {
            *p = delimc;
            cnt--;
        }

    return list;
}

#ifdef TEST
main (int argc, char *argv[])
{
    FILE    *fp;
    char    *p;
    char    *searchlist = NULL;
    char    group[255];

    if ( argc > 1 )
        searchlist = prepstrlist (argv[1], LISTDELIM);

    printf ("searchlist: %d entrys: \n", searchlist[0]);
    if ( (fp = fopen ("/etc/group", "r")) == NULL )
        exit (fprintf (stderr, "can't open file\n"));

    while ( fscanf (fp, "%[^:]:%*[^\n]\n", group) != EOF )
        if ( isinlist (group, searchlist) )
            printf ("%s\n", group);

    fclose (fp);

    printf ("searchlist: \"%s\"\n", unprepstrlist  (searchlist, *LISTDELIM));
    for ( p = searchlist; *p; p++ )
        if ( *p < 32 )
            printf ("<%d>", *p);
        else
            printf ("%c", *p);
    printf ("\n");
}
#endif