Method query

euralios_std/src/fs.rs:246–273

Query a file handle EuraliOS only

(&self)

    ///
    /// EuraliOS only
    pub fn query(&self) -> Result<FileQuery, SyscallError> {
        match rcall(&self.0,
                    message::QUERY,
                    0.into(), 0.into(), None) {
            Ok((message::JSON,
                MessageData::Value(length),
                MessageData::MemoryHandle(handle))) => {

                let u8_slice = handle.as_slice::<u8>(length as usize);
                if let Ok(s) = str::from_utf8(u8_slice) {
                    match serde_json::from_str::<Value>(s) {
                        Ok(v) => Ok(FileQuery(v)),
                        Err(err) => {
                            println!("File::query error {:?} parsing {}",
                                     err, s);
                            Err(syscalls::SYSCALL_ERROR_PARAM)
                        }
                    }
                } else {
                    Err(syscalls::SYSCALL_ERROR_PARAM)
                }
            },
            message => {
                println!("[query] received {:?}", message);
                Err(syscalls::SYSCALL_ERROR_PARAM)
            }
        }
    }

    /// Remote call. Send a message and wait for a reply
    ///