1 files changed, 85 insertions, 0 deletions
diff --git a/examples/monitor.rs b/examples/monitor.rs
new file mode 100644
index 0000000..7925907
--- /dev/null
+++ b/examples/monitor.rs
@@ -0,0 +1,85 @@
+// Copyright (c) 2018 The rust-gpio-cdev Project Developers.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use gpio_cdev::*;
+use nix::poll::*;
+use quicli::prelude::*;
+use std::os::unix::io::{AsRawFd, FromRawFd, OwnedFd};
+use structopt::StructOpt;
+
+type PollEventFlags = nix::poll::PollFlags;
+
+#[derive(Debug, StructOpt)]
+struct Cli {
+    /// The gpiochip device (e.g. /dev/gpiochip0)
+    chip: String,
+    /// The offset of the GPIO lines for the provided chip
+    lines: Vec<u32>,
+}
+
+fn do_main(args: Cli) -> anyhow::Result<()> {
+    let mut chip = Chip::new(args.chip)?;
+
+    // Get event handles for each line to monitor.
+    let mut evt_handles: Vec<LineEventHandle> = args
+        .lines
+        .into_iter()
+        .map(|off| {
+            let line = chip.get_line(off).unwrap();
+            line.events(
+                LineRequestFlags::INPUT,
+                EventRequestFlags::BOTH_EDGES,
+                "monitor",
+            )
+            .unwrap()
+        })
+        .collect();
+
+    // Create a vector of file descriptors for polling
+    let ownedfd: Vec<OwnedFd> = evt_handles
+        .iter()
+        .map(|h| unsafe { OwnedFd::from_raw_fd(h.as_raw_fd()) })
+        .collect();
+    let mut pollfds: Vec<PollFd> = ownedfd
+        .iter()
+        .map(|fd| PollFd::new(fd, PollEventFlags::POLLIN | PollEventFlags::POLLPRI))
+        .collect();
+
+    loop {
+        // poll for an event on any of the lines
+        if poll(&mut pollfds, -1)? == 0 {
+            println!("Timeout?!?");
+        } else {
+            for i in 0..pollfds.len() {
+                if let Some(revts) = pollfds[i].revents() {
+                    let h = &mut evt_handles[i];
+                    if revts.contains(PollEventFlags::POLLIN) {
+                        let event = h.get_event()?;
+                        println!("[{}] {:?}", h.line().offset(), event);
+
+                        // You can figure out the new level from the event,
+                        // but this shows that you can use the event handle
+                        // to read the value of the bit.
+                        let val = h.get_value()?;
+                        println!("    {}", val);
+                    } else if revts.contains(PollEventFlags::POLLPRI) {
+                        println!("[{}] Got a POLLPRI", h.line().offset());
+                    }
+                }
+            }
+        }
+    }
+}
+
+fn main() -> CliResult {
+    let args = Cli::from_args();
+    do_main(args).or_else(|e| {
+        error!("{:?}", e);
+        Ok(())
+    })
+}