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//! SocketCAN 硬件时间戳验证程序
//!
//! 此程序用于验证 Linux SocketCAN 是否支持硬件时间戳（SO_TIMESTAMPING）。
//! 在集成到 SocketCanAdapter 之前，先使用此程序验证环境。
//!
//! 使用方法：
//! ```bash
//! # 在另一个终端发送帧
//! cansend vcan0 123#DEADBEEF
//!
//! # 运行验证程序
//! cargo run --example timestamp_verification --target x86_64-unknown-linux-gnu
//! ```
#[cfg(not(target_os = "linux"))]
fn main() {
// 初始化日志
piper_sdk::init_logger!();
eprintln!("该示例仅支持 Linux（SocketCAN）。");
}
#[cfg(target_os = "linux")]
use nix::sys::socket::{ControlMessageOwned, MsgFlags, SockaddrStorage, recvmsg};
#[cfg(target_os = "linux")]
use socketcan::{CanSocket, Socket};
#[cfg(target_os = "linux")]
use std::io::IoSliceMut;
#[cfg(target_os = "linux")]
use std::mem;
#[cfg(target_os = "linux")]
use std::os::unix::io::AsRawFd;
#[cfg(target_os = "linux")]
fn main() -> std::result::Result<(), Box<dyn std::error::Error>> {
// 初始化日志
piper_sdk::init_logger!();
println!("SocketCAN 硬件时间戳验证程序");
println!("正在打开 vcan0 接口...");
// 1. 打开 CAN Socket
let socket = CanSocket::open("vcan0").map_err(|e| format!("Failed to open vcan0: {}", e))?;
let fd = socket.as_raw_fd();
println!("✓ vcan0 已打开 (fd: {})", fd);
// 2. 启用 SO_TIMESTAMPING
let flags = libc::SOF_TIMESTAMPING_RX_HARDWARE
| libc::SOF_TIMESTAMPING_RAW_HARDWARE
| libc::SOF_TIMESTAMPING_RX_SOFTWARE
| libc::SOF_TIMESTAMPING_SOFTWARE;
let result = unsafe {
libc::setsockopt(
fd,
libc::SOL_SOCKET,
libc::SO_TIMESTAMPING,
&flags as *const _ as *const libc::c_void,
mem::size_of::<u32>() as libc::socklen_t,
)
};
if result < 0 {
return Err(format!(
"Failed to set SO_TIMESTAMPING: {}",
std::io::Error::last_os_error()
)
.into());
}
println!("✓ SO_TIMESTAMPING 已启用");
// 3. 准备缓冲区
// CAN 2.0 帧最大 16 字节（使用 size_of 确保跨平台正确性）
const CAN_FRAME_LEN: usize = std::mem::size_of::<libc::can_frame>();
let mut frame_buf = [0u8; CAN_FRAME_LEN];
let mut cmsg_buf = [0u8; 1024]; // CMSG 缓冲区
println!("\n等待接收 CAN 帧（按 Ctrl+C 退出）...");
println!("提示：在另一个终端运行: cansend vcan0 123#DEADBEEF\n");
// 4. 接收帧（阻塞）
loop {
// 构建 IO 向量（必须在循环内，因为需要可变引用）
let mut iov = [IoSliceMut::new(&mut frame_buf)];
let msg = recvmsg::<SockaddrStorage>(fd, &mut iov, Some(&mut cmsg_buf), MsgFlags::empty())
.map_err(|e| format!("recvmsg failed: {}", e))?;
println!("=== 接收到 CAN 帧 ===");
println!("数据长度: {} 字节", msg.bytes);
// 5. 打印时间戳（验证是否能正确提取）
// 注意：nix 0.30 中使用 ScmTimestampsns，Timestamps 结构体有 system/hw_trans/hw_raw 字段
// msg.cmsgs() 返回 Result<CmsgIterator>，需要先处理错误
let mut found_timestamp = false;
match msg.cmsgs() {
Ok(cmsgs) => {
for cmsg in cmsgs {
if let ControlMessageOwned::ScmTimestampsns(timestamps) = cmsg {
found_timestamp = true;
println!("\n时间戳信息 (SCM_TIMESTAMPING):");
println!(" Timestamps 结构体字段: system, hw_trans, hw_raw");
// timestamps.system - Software (System Time) - 对应 timestamps[0]
let sw_ts = timestamps.system;
let sw_us =
sw_ts.tv_sec() as u64 * 1_000_000 + sw_ts.tv_nsec() as u64 / 1000;
println!(
" system (Software): sec={}, nsec={} ({} us)",
sw_ts.tv_sec(),
sw_ts.tv_nsec(),
sw_us
);
// timestamps.hw_trans - Hardware-Transformed (System Time) - 对应 timestamps[1]
let hw_trans_ts = timestamps.hw_trans;
let hw_trans_us = if hw_trans_ts.tv_sec() != 0 || hw_trans_ts.tv_nsec() != 0
{
hw_trans_ts.tv_sec() as u64 * 1_000_000
+ hw_trans_ts.tv_nsec() as u64 / 1000
} else {
0
};
println!(
" hw_trans (HW-Trans): sec={}, nsec={} ({} us)",
hw_trans_ts.tv_sec(),
hw_trans_ts.tv_nsec(),
hw_trans_us
);
// timestamps.hw_raw - Hardware-Raw (Device Clock) - 对应 timestamps[2]
let hw_raw_ts = timestamps.hw_raw;
let hw_raw_us = if hw_raw_ts.tv_sec() != 0 || hw_raw_ts.tv_nsec() != 0 {
hw_raw_ts.tv_sec() as u64 * 1_000_000
+ hw_raw_ts.tv_nsec() as u64 / 1000
} else {
0
};
println!(
" hw_raw (HW-Raw): sec={}, nsec={} ({} us)",
hw_raw_ts.tv_sec(),
hw_raw_ts.tv_nsec(),
hw_raw_us
);
// 验证结果
if sw_us > 0 {
println!("\n✓ 软件时间戳可用 (system)");
}
if hw_trans_us > 0 {
println!("✓ 硬件时间戳可用 (hw_trans - Transformed)");
} else {
println!(" (硬件时间戳不可用，这是正常的，因为 vcan0 是虚拟接口)");
}
if hw_raw_us > 0 {
println!("✓ 原始硬件时间戳可用 (hw_raw - Raw)");
}
}
}
},
Err(e) => {
println!("⚠ 警告：CMSG 迭代失败: {}", e);
},
}
if !found_timestamp {
println!("⚠ 警告：未找到 SCM_TIMESTAMPING 控制消息");
}
println!("====================\n");
}
}