add stdio redirection example

.github/workflows/rust.yml

@@ -18,6 +18,7 @@ jobs:
           - ping
           - dev_random
           - ping_queue
+          - redirect_stdio
     env:
       DURATION: 10s
       RUST_LOG: trace

.gitignore

@@ -1,4 +1,9 @@
 /target
 .direnv/
 .vscode/
-result
+result
+
+# For the redirect_stdio example
+stdin
+stdout
+stderr

Cargo.toml

@@ -15,10 +15,12 @@ members = [
     "examples/ping/client",
     "examples/ping/server",
 
-    "examples/dev_random",
-
     "examples/ping_queue/client",
     "examples/ping_queue/server",
+
+    "examples/dev_random",
+
+    "examples/redirect_stdio"
 ]
 
 [workspace.package]
@@ -38,6 +40,7 @@ repository = "https://github.com/DLR-FT/a653rs-linux/"
 a653rs = "0.6"
 a653rs-linux = { version = "0.2", path = "partition" }
 a653rs-linux-core = { version = "0.2", path = "core" }
+anyhow = "1.0"
 log = "0"
 nix = { version = "0.29", features = ["socket", "process", "fs", "uio", "signal", "user", "mount", "event", "sched"] }
 memmap2 = "0.9"

core/Cargo.toml

@@ -19,8 +19,8 @@ memmap2.workspace = true
 procfs.workspace = true
 polling.workspace = true
 itertools.workspace = true
+anyhow.workspace = true
 
-anyhow = "1.0"
 log = "0"
 walkdir = "2.3"
 serde = { version = "1.0", features = ["derive"] }

examples/hello_part/Cargo.toml

@@ -11,10 +11,6 @@ license = "MIT OR Apache-2.0"
 a653rs = { workspace = true, features = ["macros"] }
 a653rs-postcard = { version = "0.4", features = ["alloc"] }
 a653rs-linux.workspace = true
-nix.workspace = true
-memmap2.workspace = true
-procfs.workspace = true
-once_cell.workspace = true
 serde = "1.0"
 log = "0"
 humantime = "2.1"

examples/redirect_stdio/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "redirect_stdio"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+a653rs = { workspace = true, features = ["macros"] }
+a653rs-linux.workspace = true
+log.workspace = true
+nix.workspace = true
+anyhow.workspace = true

examples/redirect_stdio/redirect_stdio.yaml

@@ -0,0 +1,12 @@
+major_frame: 1s
+partitions:
+  - id: 0
+    name: partition_0
+    duration: 1s
+    offset: 0ms
+    period: 1s
+    image: ./target/x86_64-unknown-linux-musl/release/redirect_stdio
+    mounts:
+      - [ ./stdin, /stdin ]
+      - [ ./stdout, /stdout ]
+      - [ ./stderr, /stderr ]

examples/redirect_stdio/src/main.rs

@@ -0,0 +1,74 @@
+use std::fs::OpenOptions;
+use std::os::fd::AsRawFd;
+use std::path::Path;
+
+use a653rs::partition;
+use a653rs::prelude::PartitionExt;
+use a653rs_linux::partition::ApexLogger;
+use anyhow::Result;
+use log::LevelFilter;
+
+fn replace_stdio<T: AsRawFd, U: AsRef<Path>>(stdio: T, new: U, write: bool) -> Result<()> {
+    let new = OpenOptions::new()
+        .write(write)
+        .read(!write)
+        .truncate(write)
+        .open(new)?;
+    nix::unistd::dup2(new.as_raw_fd(), stdio.as_raw_fd())?;
+    Ok(())
+}
+
+fn main() {
+    replace_stdio(std::io::stdin(), "/stdin", false).unwrap();
+    replace_stdio(std::io::stdout(), "/stdout", true).unwrap();
+    replace_stdio(std::io::stderr(), "/stderr", true).unwrap();
+
+    ApexLogger::install_panic_hook();
+    ApexLogger::install_logger(LevelFilter::Trace).unwrap();
+
+    redirect_stdio::Partition.run()
+}
+
+#[partition(a653rs_linux::partition::ApexLinuxPartition)]
+mod redirect_stdio {
+    use log::info;
+    use std::io::BufRead;
+
+    #[start(cold)]
+    fn cold_start(mut ctx: start::Context) {
+        // create and start an aperiodic process
+        ctx.create_process_0().unwrap().start().unwrap();
+    }
+
+    // do the same as a cold_start
+    #[start(warm)]
+    fn warm_start(ctx: start::Context) {
+        cold_start(ctx);
+    }
+
+    // this aperiodic process opens /dev/random and reads some random bytes from it
+    #[aperiodic(
+        time_capacity = "Infinite",
+        stack_size = "8KB",
+        base_priority = 1,
+        deadline = "Soft"
+    )]
+    fn process_0(ctx: process_0::Context) {
+        info!("started process with redirected stdio/stdout/stderr");
+
+        info!("Reading stdin to stdout");
+        println!("Start reading stdin to stdout");
+        let stdin = std::io::stdin();
+        for line in stdin.lock().lines() {
+            println!("{}", line.unwrap())
+        }
+        println!("Finished reading stdin to stdout");
+
+        info!("Writing messages to stderr");
+        eprintln!("Error was encountered: None");
+        eprintln!("But it was printed to stderr");
+
+        info!("Terminating partition");
+        ctx.set_partition_mode(OperatingMode::Idle).unwrap();
+    }
+}

flake.nix

@@ -71,6 +71,14 @@
             name = "hello_part_no_macros";
             partitions = [ "hello_part_no_macros" ];
           }
+          {
+            name = "redirect_stdio";
+            partitions = [ "redirect_stdio" ];
+            preRun = ''
+              touch $PRJ_ROOT/std{out,err}
+              echo $'hello\nworld!\n' > $PRJ_ROOT/stdin
+            '';
+          }
           {
             name = "fuel_tank";
             partitions = [ "fuel_tank_simulation" "fuel_tank_controller" ];
@@ -103,7 +111,7 @@
               cargoTestOptions = x: x ++ [ "--package" pname ];
             } // env;
         } // (builtins.listToAttrs (builtins.map
-          ({ name, partitions }: {
+          ({ name, partitions, ... }: {
             name = "example-${name}";
             value = naersk-lib.buildPackage
               rec {
@@ -181,7 +189,7 @@
               inherit (nixpkgs.lib) flatten;
             in
             flatten (map
-              ({ name, partitions }: [
+              ({ name, partitions, preRun ? "" }: [
                 {
                   name = "run-example-${name}";
                   command = ''
@@ -192,8 +200,10 @@
                     # prepend PATH so that partition images can be found
                     PATH="target/${rust-target}/release:$PATH"
 
+                    ${preRun}
+
                     # (build &) run hypervisor
-                    RUST_LOG=''${RUST_LOG:=trace} cargo run --package a653rs-linux-hypervisor --release -- examples/${name}/${name}.yaml $@
+                    RUST_LOG=''${RUST_LOG:=trace} cargo run --package a653rs-linux-hypervisor --release -- "examples/${name}/${name}.yaml" $@
                   '';
                   help = "Run the ${name} example, consisting of the partitions: ${concatStringsSep "," partitions}";
                   category = "example";

hypervisor/Cargo.toml

@@ -21,7 +21,8 @@ polling.workspace = true
 itertools.workspace = true
 once_cell.workspace = true
 bytesize.workspace = true
-anyhow = "1.0"
+anyhow.workspace = true
+
 tempfile = "3.3"
 clone3 = "0.2"
 serde = { version = "1.0", features = ["derive"] }

hypervisor/src/hypervisor/scheduler.rs

@@ -72,6 +72,12 @@ impl<'a> PartitionTimeframeScheduler<'a> {
             return Ok(());
         }
 
+        if let OperatingMode::Idle = self.partition.get_base_run().1.mode() {
+            trace!("Partition is IDLE, waiting till the end of the partition time window");
+            std::thread::sleep(self.timeout.remaining_time());
+            return Ok(());
+        }
+
         // If we are in the normal mode at the beginning of the time frame,
         // only then we may schedule the periodic process inside a partition
         if let OperatingMode::Normal = self.partition.get_base_run().1.mode() {

partition/Cargo.toml

@@ -24,9 +24,9 @@ memmap2.workspace = true
 procfs.workspace = true
 polling.workspace = true
 once_cell.workspace = true
+anyhow.workspace = true
 
 lazy_static = "1.4"
-anyhow = "1.0"
 log.workspace = true
 tinyvec = "1.6"
 oneshot = "0.1.6"