Allow --pid-file to be used with --foreground

The PID file is now always written whether or not ACMEd is running in
the foreground. Previously, it was written only when running in the
background.
Fix #7

CHANGELOG.md

@@ -18,6 +18,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 - Wildcard certificates are now supported. In the file name, the `*` is replaced by `_`.
 
+### Changed
+- The PID file is now always written whether or not ACMEd is running in the foreground. Previously, it was written only when running in the background.
+
 ### Fixed
 - In the directory, the `externalAccountRequired` field is now a boolean instead of a string.
 

acme_common/src/lib.rs

@@ -1,9 +1,24 @@
 use daemonize::Daemonize;
+use std::fs::File;
+use std::io::prelude::*;
+use std::process;
 
 pub mod crypto;
 pub mod error;
 pub mod logs;
 
+macro_rules! exit_match {
+    ($e: expr) => {
+        match $e {
+            Ok(_) => {}
+            Err(e) => {
+                eprintln!("Error: {}", e);
+                std::process::exit(3);
+            }
+        }
+    };
+}
+
 pub fn b64_encode<T: ?Sized + AsRef<[u8]>>(input: &T) -> String {
     base64::encode_config(input, base64::URL_SAFE_NO_PAD)
 }
@@ -11,12 +26,16 @@ pub fn b64_encode<T: ?Sized + AsRef<[u8]>>(input: &T) -> String {
 pub fn init_server(foreground: bool, pid_file: &str) {
     if !foreground {
         let daemonize = Daemonize::new().pid_file(pid_file);
-        match daemonize.start() {
-            Ok(_) => {}
-            Err(e) => {
-                eprintln!("Error: {}", e);
-                std::process::exit(3);
-            }
-        }
+        exit_match!(daemonize.start());
+    } else {
+        exit_match!(write_pid_file(pid_file));
     }
 }
+
+fn write_pid_file(pid_file: &str) -> Result<(), error::Error> {
+    let data = format!("{}\n", process::id()).into_bytes();
+    let mut file = File::create(pid_file)?;
+    file.write_all(&data)?;
+    file.sync_all()?;
+    Ok(())
+}

acmed/src/main.rs

@@ -86,8 +86,7 @@ fn main() {
                 .long("pid-file")
                 .help("Specifies the location of the PID file")
                 .takes_value(true)
-                .value_name("FILE")
-                .conflicts_with("foreground"),
+                .value_name("FILE"),
         )
         .arg(
             Arg::with_name("root-cert")

tacd/src/main.rs

@@ -128,8 +128,7 @@ fn main() {
                 .long("pid-file")
                 .help("Specifies the location of the PID file")
                 .takes_value(true)
-                .value_name("FILE")
-                .conflicts_with("foreground"),
+                .value_name("FILE"),
         )
         .get_matches();