Function convertPathnameToDirName

freebsd/contrib/zstd/programs/util.c:714–742

this function requires a mutable input string */

/* this function requires a mutable input string */
static void convertPathnameToDirName(char *pathname)
{
    size_t len = 0;
    char* pos = NULL;
    /* get dir name from pathname similar to 'dirname()' */
    assert(pathname != NULL);

    /* remove trailing '/' chars */
    len = strlen(pathname);
    assert(len > 0);
    while (pathname[len] == PATH_SEP) {
        pathname[len] = '\0';
        len--;
    }
    if (len == 0) return;

    /* if input is a single file, return '.' instead. i.e.
     * "xyz/abc/file.txt" => "xyz/abc"
       "./file.txt"       => "."
       "file.txt"         => "."
     */
    pos = strrchr(pathname, PATH_SEP);
    if (pos == NULL) {
        pathname[0] = '.';
        pathname[1] = '\0';
    } else {
        *pos = '\0';
    }
}

/* pathname must be valid */
static const char* trimLeadingRootChar(const char *pathname)