Add Rosetta check for Mac (#355)

* Add Rosetta check for Mac

* Use a different, better method

* Setup sysctl error

Cargo.lock

@@ -385,6 +385,18 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "enum-as-inner"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c9720bba047d567ffc8a3cba48bf19126600e249ab7f128e9233e6376976a116"
+dependencies = [
+ "heck",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "erased-serde"
 version = "0.3.25"
@@ -985,6 +997,7 @@ dependencies = [
  "serde_json",
  "serde_with",
  "strum",
+ "sysctl",
  "tar",
  "target-lexicon",
  "tempfile",
@@ -1411,6 +1424,15 @@ version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ef703b7cb59335eae2eb93ceb664c0eb7ea6bf567079d843e09420219668e072"
 
+[[package]]
+name = "same-file"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "93fc1dc3aaa9bfed95e02e6eadabb4baf7e3078b0bd1b4d7b6b0b68378900502"
+dependencies = [
+ "winapi-util",
+]
+
 [[package]]
 name = "schannel"
 version = "0.1.21"
@@ -1649,6 +1671,20 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "sysctl"
+version = "0.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ed66d6a2ccbd656659289bc90767895b7abbdec897a0fc6031aca3ed1cb51d3e"
+dependencies = [
+ "bitflags",
+ "byteorder",
+ "enum-as-inner",
+ "libc",
+ "thiserror",
+ "walkdir",
+]
+
 [[package]]
 name = "tar"
 version = "0.4.38"
@@ -2025,6 +2061,16 @@ version = "0.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "49874b5167b65d7193b8aba1567f5c7d93d001cafc34600cee003eda787e483f"
 
+[[package]]
+name = "walkdir"
+version = "2.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "36df944cda56c7d8d8b7496af378e6b16de9284591917d307c9b4d313c44e698"
+dependencies = [
+ "same-file",
+ "winapi-util",
+]
+
 [[package]]
 name = "want"
 version = "0.3.0"

Cargo.toml

@@ -59,6 +59,7 @@ is_ci = { version = "1.1.1", default-features = false, optional = true }
 strum = { version = "0.24.1", features = ["derive"] }
 nix-config-parser = { version = "0.1.2", features = ["serde"] }
 which = "4.4.0"
+sysctl = "0.5.4"
 
 [dev-dependencies]
 eyre = { version = "0.6.8", default-features = false, features = [ "track-caller" ] }

src/planner/macos.rs

@@ -87,6 +87,8 @@ impl Planner for Macos {
     }
 
     async fn plan(&self) -> Result<Vec<StatefulAction<Box<dyn Action>>>, PlannerError> {
+        ensure_not_running_in_rosetta().await?;
+
         let root_disk = match &self.root_disk {
             root_disk @ Some(_) => root_disk.clone(),
             None => {
@@ -214,3 +216,23 @@ impl Into<BuiltinPlanner> for Macos {
         BuiltinPlanner::Macos(self)
     }
 }
+
+async fn ensure_not_running_in_rosetta() -> Result<(), PlannerError> {
+    use sysctl::{Ctl, Sysctl};
+    const CTLNAME: &str = "sysctl.proc_translated";
+
+    match Ctl::new(CTLNAME) {
+        // This Mac doesn't have Rosetta!
+        Err(sysctl::SysctlError::NotFound(_)) => (),
+        Err(e) => Err(e)?,
+        Ok(ctl) => {
+            let str_val = ctl.value_string()?;
+
+            if str_val == "1" {
+                return Err(PlannerError::RosettaDetected);
+            }
+        },
+    }
+
+    Ok(())
+}

src/planner/mod.rs

@@ -298,6 +298,10 @@ pub enum PlannerError {
     /// A MacOS (Darwin) plist related error
     #[error(transparent)]
     Plist(#[from] plist::Error),
+    #[error(transparent)]
+    Sysctl(#[from] sysctl::SysctlError),
+    #[error("Detected that this process is running under Rosetta, using Nix in Rosetta is not supported (Please open an issue with your use case)")]
+    RosettaDetected,
     /// A Linux SELinux related error
     #[error("This installer doesn't yet support SELinux in `Enforcing` mode. If SELinux is important to you, please see https://github.com/DeterminateSystems/nix-installer/issues/124. You can also try again after setting SELinux to `Permissive` mode with `setenforce Permissive`")]
     SelinuxEnforcing,
@@ -322,6 +326,8 @@ impl HasExpectedErrors for PlannerError {
             PlannerError::Action(_) => None,
             PlannerError::InstallSettings(_) => None,
             PlannerError::Plist(_) => None,
+            PlannerError::Sysctl(_) => None,
+            this @ PlannerError::RosettaDetected => Some(Box::new(this)),
             PlannerError::Utf8(_) => None,
             PlannerError::SelinuxEnforcing => Some(Box::new(self)),
             PlannerError::Custom(_) => None,