the most overcomplicated chdir implementation

chdir.c

void chdir(const char* path)
{
    if(*path == '/')
    {
        strncpy(root, path, 262);
    }
    else
    {
        int len = 262 - strnlen(root, 262);
        
        char* r = root + strnlen(root, 262);
        
        const char* ptr = path;
        const char* end = path;
        while(1)
        {
            if(!*end) break;
            
            ptr = end;
            
            while(*end && *end != '/') end++;
            while(*end == '/') end++;
            
            if(*ptr == '.')
            {
                if(!ptr[1]) break;
                if(ptr[1] == '/') continue;
                
                if(ptr[1] == '.')
                {
                    if(r != root)
                    do
                    {
                        *(--r) = '\0';
                        len++;
                        
                        while(r != root && *(--r) != '/')
                        {
                            *r = 0;
                            len++;
                        }
                    }
                    while(0);
                    
                    if(r == root) *(r++) = '/';
                    
                    continue;
                }
            }
            
            while(len && *ptr)
            {
                *(r++) = *ptr;
                len--;
                
                if(*(ptr++) == '/')
                {
                    ptr++;
                    break;
                }
                if(!*ptr)
                {
                    if(len)
                    {
                        *(r++) = '/';
                        len--;
                    }
                    break;
                }
            }
            if(len)
            {
                if(*(--r) != '/')
                {
                    *(++r) = '/';
                    *(++r) = '\0';
                    len--;
                }
            }
            else
            {
                *(r--) = 0;
                *(r++) = '/';
            }
        }
    }
}