strtok_r for MinGW

问题:

strtok_r is the reentrant variant of strtok. It is POSIX-conformant. However, it is missing from MinGW, and I'm trying to compile a program that is using it.

Is there any way I could add a standard implementation of this function, perhaps to the project's own code, or to MinGW's standard library functions?

回答1:

Since there are some license questions about the code from another answer, here's one that's explicitly public domain:

/* 
 * public domain strtok_r() by Charlie Gordon
 *
 *   from comp.lang.c  9/14/2007
 *
 *      http://groups.google.com/group/comp.lang.c/msg/2ab1ecbb86646684
 *
 *     (Declaration that it's public domain):
 *      http://groups.google.com/group/comp.lang.c/msg/7c7b39328fefab9c
 */

char* strtok_r(
    char *str, 
    const char *delim, 
    char **nextp)
{
    char *ret;

    if (str == NULL)
    {
        str = *nextp;
    }

    str += strspn(str, delim);

    if (*str == '\0')
    {
        return NULL;
    }

    ret = str;

    str += strcspn(str, delim);

    if (*str)
    {
        *str++ = '\0';
    }

    *nextp = str;

    return ret;
}

回答2:

Here's the source code which you can simply add to your own library/function in your project:

char *strtok_r(char *str, const char *delim, char **save)
{
    char *res, *last;

    if( !save )
        return strtok(str, delim);
    if( !str && !(str = *save) )
        return NULL;
    last = str + strlen(str);
    if( (*save = res = strtok(str, delim)) )
    {
        *save += strlen(res);
        if( *save < last )
            (*save)++;
        else
            *save = NULL;
    }
    return res;
}

回答3:

Is the FreeBSD implementation any use to you?

Its liberally licensed but integrating it may have some requirements on your project documentation (adding an acknowledgement that the code has been included).

回答4:

MINGW has no implementation of strtok_r. However you can find a thread-safe implementation in the link below:

http://www.raspberryginger.com/jbailey/minix/html/strtok__r_8c-source.html