[V3,3/4] libgpiod: Add rust examples

diff --git a/bindings/rust/examples/gpiodetect.rs b/bindings/rust/examples/gpiodetect.rs
new file mode 100644
index 000000000000..505ad1e3420d
--- /dev/null
+++ b/bindings/rust/examples/gpiodetect.rs
@@ -0,0 +1,37 @@ 
+// SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
+//
+// Copyright 2021 Linaro Ltd. All Rights Reserved.
+//     Viresh Kumar <viresh.kumar@linaro.org>
+//
+// Simplified Rust implementation of gpiodetect tool.
+
+use std::env;
+use std::fs;
+use std::path::Path;
+
+use libgpiod::{gpiod_is_gpiochip_device, Chip};
+
+fn main() {
+    let args: Vec<String> = env::args().collect();
+    if args.len() > 1 {
+        println!("Usage: {}", args[0]);
+        return;
+    }
+
+    for entry in fs::read_dir(Path::new("/dev")).unwrap() {
+        let pathbuf = entry.unwrap().path();
+        let path = pathbuf.to_str().unwrap();
+
+        if gpiod_is_gpiochip_device(path) {
+            let chip = Chip::open(path).unwrap();
+            let ngpio = chip.get_num_lines();
+
+            println!(
+                "{} [{}] ({})",
+                chip.get_name().unwrap(),
+                chip.get_label().unwrap(),
+                ngpio
+            );
+        }
+    }
+}
diff --git a/bindings/rust/examples/gpiofind.rs b/bindings/rust/examples/gpiofind.rs
new file mode 100644
index 000000000000..7c20d71acb9f
--- /dev/null
+++ b/bindings/rust/examples/gpiofind.rs
@@ -0,0 +1,42 @@ 
+// SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
+//
+// Copyright 2021 Linaro Ltd. All Rights Reserved.
+//     Viresh Kumar <viresh.kumar@linaro.org>
+//
+// Simplified Rust implementation of gpiofind tool.
+
+use std::env;
+use std::fs;
+use std::path::Path;
+
+use libgpiod::{gpiod_is_gpiochip_device, Chip};
+
+fn main() {
+    let args: Vec<String> = env::args().collect();
+    if args.len() != 2 {
+        println!("Usage: {} <line-name>", args[0]);
+        return;
+    }
+
+    for entry in fs::read_dir(Path::new("/dev")).unwrap() {
+        let pathbuf = entry.unwrap().path();
+        let path = pathbuf.to_str().unwrap();
+
+        if gpiod_is_gpiochip_device(path) {
+            let chip = Chip::open(path).unwrap();
+
+            let offset = chip.find_line(&args[1]);
+            if offset.is_ok() {
+                println!(
+                    "Line {} found: Chip: {}, offset: {}",
+                    args[1],
+                    chip.get_name().unwrap(),
+                    offset.unwrap()
+                );
+                return;
+            }
+        }
+    }
+
+    println!("Failed to find line: {}", args[1]);
+}
diff --git a/bindings/rust/examples/gpioget.rs b/bindings/rust/examples/gpioget.rs
new file mode 100644
index 000000000000..0105cefdc119
--- /dev/null
+++ b/bindings/rust/examples/gpioget.rs
@@ -0,0 +1,42 @@ 
+// SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
+//
+// Copyright 2021 Linaro Ltd. All Rights Reserved.
+//     Viresh Kumar <viresh.kumar@linaro.org>
+//
+// Simplified Rust implementation of gpioget tool.
+
+use std::env;
+
+use libgpiod::{Chip, Direction, LineConfig, RequestConfig};
+
+fn main() {
+    let args: Vec<String> = env::args().collect();
+    if args.len() < 3 {
+        println!("Usage: {} <chip> <line_offset0> ...", args[0]);
+        return;
+    }
+
+    let mut config = LineConfig::new().unwrap();
+    let mut offsets = Vec::<u32>::new();
+
+    for arg in &args[2..] {
+        let offset = arg.parse::<u32>().unwrap();
+
+        offsets.push(offset);
+        config.set_direction_offset(Direction::Input, offset);
+    }
+
+    let path = format!("/dev/gpiochip{}", args[1]);
+    let chip = Chip::open(&path).unwrap();
+
+    let rconfig = RequestConfig::new().unwrap();
+    rconfig.set_consumer(&args[0]);
+    rconfig.set_offsets(&offsets);
+
+    let request = chip.request_lines(&rconfig, &config).unwrap();
+
+    let mut values: Vec<i32> = vec![0; offsets.len()];
+    request.get_values(&mut values).unwrap();
+
+    println!("{:?}", values);
+}
diff --git a/bindings/rust/examples/gpioinfo.rs b/bindings/rust/examples/gpioinfo.rs
new file mode 100644
index 000000000000..1d74a17e3c90
--- /dev/null
+++ b/bindings/rust/examples/gpioinfo.rs
@@ -0,0 +1,89 @@ 
+// SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
+//
+// Copyright 2021 Linaro Ltd. All Rights Reserved.
+//     Viresh Kumar <viresh.kumar@linaro.org>
+//
+// Simplified Rust implementation of gpioinfo tool.
+
+use std::env;
+use std::fs;
+use std::path::Path;
+
+use libgpiod::{gpiod_is_gpiochip_device, Chip, Direction};
+
+fn line_info(chip: &Chip, offset: u32) {
+    let info = chip.line_info(offset).unwrap();
+    let off = info.get_offset();
+
+    let name = match info.get_name() {
+        Ok(name) => name,
+        _ => "unused",
+    };
+
+    let consumer = match info.get_consumer() {
+        Ok(name) => name,
+        _ => "unnamed",
+    };
+
+    let low = if info.is_active_low() {
+        "active-low"
+    } else {
+        "active-high"
+    };
+
+    let dir = match info.get_direction().unwrap() {
+        Direction::AsIs => "None",
+        Direction::Input => "Input",
+        Direction::Output => "Output",
+    };
+
+    println!(
+        "\tline {:>3}\
+              \t{:>10}\
+              \t{:>10}\
+              \t{:>6}\
+              \t{:>14}",
+        off, name, consumer, dir, low
+    );
+}
+
+fn chip_info(path: &str) {
+    if gpiod_is_gpiochip_device(path) {
+        let chip = Chip::open(path).unwrap();
+        let ngpio = chip.get_num_lines();
+
+        println!("GPIO Chip name: {}", chip.get_name().unwrap());
+        println!("\tlabel: {}", chip.get_label().unwrap());
+        println!("\tpath: {}", chip.get_path().unwrap());
+        println!("\tngpio: {}\n", ngpio);
+
+        println!("\tLine information:");
+
+        for offset in 0..ngpio {
+            line_info(&chip, offset);
+        }
+        println!("\n");
+    }
+}
+
+fn main() {
+    let args: Vec<String> = env::args().collect();
+    if args.len() > 2 {
+        println!("Usage: {}", args[0]);
+        return;
+    }
+
+    if args.len() == 1 {
+        for entry in fs::read_dir(Path::new("/dev")).unwrap() {
+            let pathbuf = entry.unwrap().path();
+            let path = pathbuf.to_str().unwrap();
+
+            chip_info(path);
+        }
+    } else {
+        let index = args[1].parse::<u32>().unwrap();
+        let path = format!("/dev/gpiochip{}", index);
+
+        chip_info(&path);
+    }
+}
diff --git a/bindings/rust/examples/gpiomon.rs b/bindings/rust/examples/gpiomon.rs
new file mode 100644
index 000000000000..cf6700c5a960
--- /dev/null
+++ b/bindings/rust/examples/gpiomon.rs
@@ -0,0 +1,68 @@ 
+// SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
+//
+// Copyright 2021 Linaro Ltd. All Rights Reserved.
+//     Viresh Kumar <viresh.kumar@linaro.org>
+//
+// Simplified Rust implementation of the gpiomon tool.
+
+use std::env;
+use std::time::Duration;
+
+use libgpiod::{Chip, Edge, EdgeEventBuffer, Error, LineConfig, LineEdgeEvent, RequestConfig};
+
+fn usage(name: &str) {
+    println!("Usage: {} <chip> <offset0> ...", name);
+}
+
+fn main() {
+    let args: Vec<String> = env::args().collect();
+    if args.len() < 3 {
+        usage(&args[0]);
+        return;
+    }
+
+    let mut config = LineConfig::new().unwrap();
+    let mut offsets = Vec::<u32>::new();
+
+    for arg in &args[2..] {
+        let offset = arg.parse::<u32>().unwrap();
+
+        offsets.push(offset);
+    }
+
+    config.set_edge_detection(Edge::Both);
+
+    let path = format!("/dev/gpiochip{}", args[1]);
+    let chip = Chip::open(&path).unwrap();
+
+    let rconfig = RequestConfig::new().unwrap();
+    rconfig.set_offsets(&offsets);
+
+    let buffer = EdgeEventBuffer::new(1).unwrap();
+    let request = chip.request_lines(&rconfig, &config).unwrap();
+
+    loop {
+        match request.edge_event_wait(Duration::new(1, 0)) {
+            Err(Error::OperationTimedOut) => continue,
+            Err(x) => {
+                println!("{:?}", x);
+                return;
+            }
+            Ok(()) => (),
+        }
+
+        let count = request.edge_event_read(&buffer, 1).unwrap();
+        if count == 1 {
+            let event = buffer.get_event(0).unwrap();
+            println!(
+                "line: {} type: {}, time: {:?}",
+                event.get_line_offset(),
+                match event.get_event_type().unwrap() {
+                    LineEdgeEvent::Rising => "Rising",
+                    LineEdgeEvent::Falling => "Falling",
+                },
+                event.get_timestamp()
+            );
+        }
+    }
+}
diff --git a/bindings/rust/examples/gpioset.rs b/bindings/rust/examples/gpioset.rs
new file mode 100644
index 000000000000..3b8f9d227181
--- /dev/null
+++ b/bindings/rust/examples/gpioset.rs
@@ -0,0 +1,52 @@ 
+// SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
+//
+// Copyright 2021 Linaro Ltd. All Rights Reserved.
+//     Viresh Kumar <viresh.kumar@linaro.org>
+//
+// Simplified Rust implementation of the gpioset tool.
+
+use std::env;
+
+use libgpiod::{Chip, Direction, LineConfig, RequestConfig};
+
+fn usage(name: &str) {
+    println!("Usage: {} <chip> <line_offset0>=<value0> ...", name);
+}
+
+fn main() {
+    let args: Vec<String> = env::args().collect();
+    if args.len() < 3 {
+        usage(&args[0]);
+        return;
+    }
+
+    let mut config = LineConfig::new().unwrap();
+    let mut offsets = Vec::<u32>::new();
+    let mut values = Vec::<i32>::new();
+
+    for arg in &args[2..] {
+        let pair: Vec<&str> = arg.split('=').collect();
+        if pair.len() != 2 {
+            usage(&args[0]);
+            return;
+        }
+
+        let offset = pair[0].parse::<u32>().unwrap();
+        let value = pair[1].parse::<u32>().unwrap();
+
+        offsets.push(offset);
+        values.push(value as i32);
+    }
+
+    config.set_direction(Direction::Output);
+    config.set_output_values(&offsets, &values);
+
+    let path = format!("/dev/gpiochip{}", args[1]);
+    let chip = Chip::open(&path).unwrap();
+
+    let rconfig = RequestConfig::new().unwrap();
+    rconfig.set_consumer(&args[0]);
+    rconfig.set_offsets(&offsets);
+
+    chip.request_lines(&rconfig, &config).unwrap();
+}