https://yyu-nim.github.io/rust/nvmf/chatgpt/2023/03/18/nvmf-1-intro.html

[utterances-bot]

nvmf <1> - introduction (feat. ChatGPT) | Production-ready Rust Libraries (PRL)

ChatGPT를 사용하면 블로그를 편하게 찍어낼 수 있다는 이야기를 들어, 아침에 일어나 “폰”으로 ChatGPT 에게 물어보았다, 아니 여쭤보았다:

https://yyu-nim.github.io/rust/nvmf/chatgpt/2023/03/18/nvmf-1-intro.html

[yyu-nim]

use std::io::{Read, Write};
use std::net::{TcpListener, TcpStream};

fn main() -> std::io::Result<()> {
    let listener = TcpListener::bind("127.0.0.1:1234")?;

    // Wait for a connection
    let (mut socket, _) = listener.accept()?;

    loop {
        // Read the NVMe-oF command header
        let mut buf = [0u8; 128];
        let len = socket.read(&mut buf)?;

        // If we've reached the end of the stream, break out of the loop
        if len == 0 {
            break;
        }

        // Pattern match on the command code in the NVMe-oF header
        match buf[0] {
            // NVMe-oF Connect command
            0x00 => {
                // Send a simple response
                let response = b"Hello from the NVMe-oF target!";
                socket.write_all(response)?;
            },
            // NVMe-oF Command Capsule command
            0x01 => {
                // TODO: Implement command capsule handling
            },
            // NVMe-oF Fabrics Discovery command
            0x02 => {
                // TODO: Implement fabrics discovery handling
            },
            // NVMe-oF Fabrics Get Log Page command
            0x03 => {
                // TODO: Implement fabrics get log page handling
            },
            // NVMe-oF Fabrics Set Features command
            0x04 => {
                // TODO: Implement fabrics set features handling
            },
            // NVMe-oF Fabrics Get Features command
            0x05 => {
                // TODO: Implement fabrics get features handling
            },
            // NVMe-oF Fabrics Asynchronous Event Request command
            0x06 => {
                // TODO: Implement fabrics asynchronous event request handling
            },
            // NVMe-oF Fabrics Asynchronous Event Completion command
            0x07 => {
                // TODO: Implement fabrics asynchronous event completion handling
            },
            // NVMe-oF Fabrics Firmware Activate command
            0x08 => {
                // TODO: Implement fabrics firmware activate handling
            },
            // NVMe-oF Fabrics Firmware Image Download command
            0x09 => {
                // TODO: Implement fabrics firmware image download handling
            },
            // Other NVMe-oF commands...
            _ => {
                // TODO: Handle unknown commands
            }
        }
    }

    Ok(())
}

이런식으로 스펙을 줄줄 외워서 skeleton 을 만들어 주기도 함

use std::io::{Read, Write};
use std::net::{TcpListener, TcpStream};

fn main() -> std::io::Result<()> {
    let listener = TcpListener::bind("127.0.0.1:1234")?;

    // Wait for a connection
    let (mut socket, _) = listener.accept()?;

    loop {
        // Read the NVMe-oF command header
        let mut buf = [0u8; 128];
        let len = socket.read(&mut buf)?;

        // If we've reached the end of the stream, break out of the loop
        if len == 0 {
            break;
        }

        // Pattern match on the command code in the NVMe-oF header
        match buf[0] {
            // NVMe-oF Connect command
            0x00 => {
                // Send a simple response
                let response = b"Hello from the NVMe-oF target!";
                socket.write_all(response)?;
            },
            // NVMe-oF Command Capsule command
            0x01 => {
                // Get the buffer offset and length from the NVMe-oF header
                let data_offset = ((buf[16] as u32) << 24) | ((buf[17] as u32) << 16) | ((buf[18] as u32) << 8) | buf[19] as u32;
                let data_len = ((buf[20] as u32) << 24) | ((buf[21] as u32) << 16) | ((buf[22] as u32) << 8) | buf[23] as u32;

                // Read the command capsule from the stream
                let mut cmd_buf = vec![0u8; data_len as usize];
                socket.read_exact(&mut cmd_buf)?;

                // Parse the command capsule
                let opcode = ((cmd_buf[0] as u32) << 24) | ((cmd_buf[1] as u32) << 16) | ((cmd_buf[2] as u32) << 8) | cmd_buf[3] as u32;
                let nsid = ((cmd_buf[4] as u32) << 24) | ((cmd_buf[5] as u32) << 16) | ((cmd_buf[6] as u32) << 8) | cmd_buf[7] as u32;
                let data = &cmd_buf[8..];

                // Parse the opcode into a string term
                let opcode_str = match opcode {
                    0x00 => "Delete I/O Submission Queue",
                    0x01 => "Create I/O Submission Queue",
                    0x02 => "Get Log Page",
                    0x04 => "Delete I/O Completion Queue",
                    0x05 => "Create I/O Completion Queue",
                    0x06 => "Identify Controller",
                    0x07 => "Abort Command",
                    0x09 => "Get Features",
                    0x0a => "Set Features",
                    0x0b => "Asynchronous Event Request",
                    0x0c => "Namespace Management",
                    0x0d => "Firmware Commit",
                    0x0e => "Firmware Image Download",
                    _ => "Unknown Opcode"
                };

                println!("Received command capsule with opcode '{}'", opcode_str);

                // TODO: Implement command handling based on the opcode and data
            },

이런식으로 opcode 별 주석이나 human readable string map을 주기도 함.