Create initial mock executable

Simply creates a special file in the current working directory, prints
its command line arguments into it and waits for it to be removed so it
finishes.

3 files changed, 62 insertions, 0 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 6dc877d08f..10e0145904 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -834,6 +834,9 @@ dependencies = [
 [[package]]
 name = "mullvad-tests"
 version = "0.1.0"
+dependencies = [
+ "notify 4.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "mullvad-types"
diff --git a/mullvad-tests/Cargo.toml b/mullvad-tests/Cargo.toml
index 0c9dec8780..5b3df950df 100644
--- a/mullvad-tests/Cargo.toml
+++ b/mullvad-tests/Cargo.toml
@@ -6,3 +6,4 @@ description = "Mullvad test specific modules and binaries"
 license = "GPL-3.0"
 
 [dependencies]
+notify = "4.0"
diff --git a/mullvad-tests/src/bin/mock_openvpn.rs b/mullvad-tests/src/bin/mock_openvpn.rs
new file mode 100644
index 0000000000..b5c1ff8be4
--- /dev/null
+++ b/mullvad-tests/src/bin/mock_openvpn.rs
@@ -0,0 +1,58 @@
+extern crate notify;
+
+use std::env;
+use std::fs::File;
+use std::io::Write;
+use std::path::{Path, PathBuf};
+use std::sync::mpsc;
+
+use notify::{raw_watcher, RawEvent, RecursiveMode, Watcher};
+
+fn main() {
+    let (file, path) = create_args_file();
+
+    write_command_line(file);
+    wait_for_file_to_be_deleted(path);
+}
+
+fn create_args_file() -> (File, PathBuf) {
+    let path = PathBuf::from(
+        env::var_os("MOCK_OPENVPN_ARGS_FILE").expect("Missing mock OpenVPN arguments file path"),
+    );
+    let file = File::create(&path).expect("Failed to create mock OpenVPN arguments file");
+
+    (file, path)
+}
+
+fn write_command_line(mut file: File) {
+    for argument in env::args() {
+        let escaped_argument = argument
+            .replace("\\", "\\\\")
+            .replace("\n", "\\n")
+            .replace("\r", "\\r");
+
+        writeln!(file, "{}", escaped_argument).expect("Failed to write argument to file");
+    }
+}
+
+fn wait_for_file_to_be_deleted<P: AsRef<Path>>(file: P) {
+    let file = file.as_ref();
+    let (tx, rx) = mpsc::channel();
+
+    let mut watcher = raw_watcher(tx).expect(&format!(
+        "Failed to create file watcher for \"{}\"",
+        file.display()
+    ));
+
+    watcher
+        .watch(&file, RecursiveMode::NonRecursive)
+        .expect(&format!("Failed to watch file: {}", file.display()));
+
+    for event in rx {
+        if let RawEvent { op: Ok(op), .. } = event {
+            if op.contains(notify::op::REMOVE) {
+                break;
+            }
+        }
+    }
+}