feat(process): use TryFrom to convert to Stdio

compio-rs · May 27, 2024 · 7a6a0e6 · 7a6a0e6
1 parent 34e3f19
commit 7a6a0e6
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Showing 3 changed files with 51 additions and 37 deletions.
diff --git a/compio-process/src/lib.rs b/compio-process/src/lib.rs
@@ -171,21 +171,21 @@ impl Command {
     }
 
     /// Configuration for the child process’s standard input (stdin) handle.
-    pub fn stdin(&mut self, cfg: impl Into<process::Stdio>) -> &mut Self {
-        self.0.stdin(cfg);
-        self
+    pub fn stdin<S: TryInto<process::Stdio>>(&mut self, cfg: S) -> Result<&mut Self, S::Error> {
+        self.0.stdin(cfg.try_into()?);
+        Ok(self)
     }
 
     /// Configuration for the child process’s standard output (stdout) handle.
-    pub fn stdout(&mut self, cfg: impl Into<process::Stdio>) -> &mut Self {
-        self.0.stdout(cfg);
-        self
+    pub fn stdout<S: TryInto<process::Stdio>>(&mut self, cfg: S) -> Result<&mut Self, S::Error> {
+        self.0.stdout(cfg.try_into()?);
+        Ok(self)
     }
 
     /// Configuration for the child process’s standard error (stderr) handle.
-    pub fn stderr(&mut self, cfg: impl Into<process::Stdio>) -> &mut Self {
-        self.0.stderr(cfg);
-        self
+    pub fn stderr<S: TryInto<process::Stdio>>(&mut self, cfg: S) -> Result<&mut Self, S::Error> {
+        self.0.stderr(cfg.try_into()?);
+        Ok(self)
     }
 
     /// Returns the path to the program.
@@ -409,15 +409,16 @@ impl ChildStdout {
     }
 }
 
-impl From<ChildStdout> for process::Stdio {
-    fn from(value: ChildStdout) -> Self {
-        Self::from(
-            value
-                .0
-                .into_inner()
-                .try_unwrap()
-                .expect("the handle is being used"),
-        )
+impl TryFrom<ChildStdout> for process::Stdio {
+    type Error = ChildStdout;
+
+    fn try_from(value: ChildStdout) -> Result<Self, ChildStdout> {
+        value
+            .0
+            .into_inner()
+            .try_unwrap()
+            .map(Self::from)
+            .map_err(|fd| ChildStdout(unsafe { Attacher::from_shared_fd_unchecked(fd) }))
     }
 }
 
@@ -430,15 +431,16 @@ impl ChildStderr {
     }
 }
 
-impl From<ChildStderr> for process::Stdio {
-    fn from(value: ChildStderr) -> Self {
-        Self::from(
-            value
-                .0
-                .into_inner()
-                .try_unwrap()
-                .expect("the handle is being used"),
-        )
+impl TryFrom<ChildStderr> for process::Stdio {
+    type Error = ChildStderr;
+
+    fn try_from(value: ChildStderr) -> Result<Self, ChildStderr> {
+        value
+            .0
+            .into_inner()
+            .try_unwrap()
+            .map(Self::from)
+            .map_err(|fd| ChildStderr(unsafe { Attacher::from_shared_fd_unchecked(fd) }))
     }
 }
 
@@ -452,14 +454,15 @@ impl ChildStdin {
     }
 }
 
-impl From<ChildStdin> for process::Stdio {
-    fn from(value: ChildStdin) -> Self {
-        Self::from(
-            value
-                .0
-                .into_inner()
-                .try_unwrap()
-                .expect("the handle is being used"),
-        )
+impl TryFrom<ChildStdin> for process::Stdio {
+    type Error = ChildStdin;
+
+    fn try_from(value: ChildStdin) -> Result<Self, ChildStdin> {
+        value
+            .0
+            .into_inner()
+            .try_unwrap()
+            .map(Self::from)
+            .map_err(|fd| ChildStdin(unsafe { Attacher::from_shared_fd_unchecked(fd) }))
     }
 }
diff --git a/compio-process/tests/process.rs b/compio-process/tests/process.rs
@@ -38,6 +38,7 @@ async fn echo() {
     let child = cmd
         .arg("echo hello world")
         .stdout(Stdio::piped())
+        .unwrap()
         .spawn()
         .unwrap();
 
@@ -58,7 +59,8 @@ async fn arg0() {
     cmd.arg0("test_string")
         .arg("-c")
         .arg("echo $0")
-        .stdout(Stdio::piped());
+        .stdout(Stdio::piped())
+        .unwrap();
 
     let output = cmd.output().await.unwrap();
     assert_eq!(output.stdout, b"test_string\n");

diff --git a/compio-runtime/src/attacher.rs b/compio-runtime/src/attacher.rs
@@ -30,6 +30,15 @@ impl<S> Attacher<S> {
             source: SharedFd::new(source),
         }
     }
+
+    /// Create [`Attacher`] without trying to attach the source.
+    ///
+    /// # Safety
+    ///
+    /// See [`Attacher::new_unchecked`].
+    pub unsafe fn from_shared_fd_unchecked(source: SharedFd<S>) -> Self {
+        Self { source }
+    }
 }
 
 impl<S: AsRawFd> Attacher<S> {