fdt_get_path

int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
{
    int pdepth = 0, p = 0;
    int offset, depth, namelen;
    const char *name;
 
    FDT_RO_PROBE(fdt);
 
    if (buflen < 2)
        return -FDT_ERR_NOSPACE;
 
    for (offset = 0, depth = 0;
         (offset >= 0) && (offset <= nodeoffset);
         offset = fdt_next_node(fdt, offset, &depth)) {
        while (pdepth > depth) {
            do {
                p--;
            } while (buf[p-1] != '/');
            pdepth--;
        }
 
        if (pdepth >= depth) {
            name = fdt_get_name(fdt, offset, &namelen);
            if (!name)
                return namelen;
            if ((p + namelen + 1) <= buflen) {
                memcpy(buf + p, name, namelen);
                p += namelen;
                buf[p++] = '/';
                pdepth++;
            }
        }
 
        if (offset == nodeoffset) {
            if (pdepth < (depth + 1))
                return -FDT_ERR_NOSPACE;
 
            if (p > 1) /* special case so that root path is "/", not "" */
                p--;
            buf[p] = '\0';
            return 0;
        }
    }
 
    if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
        return -FDT_ERR_BADOFFSET;
    else if (offset == -FDT_ERR_BADOFFSET)
        return -FDT_ERR_BADSTRUCTURE;
 
    return offset; /* error from fdt_next_node() */
}
函数源码
