From 676885d7f6551ed0de7dc1a10670ef35c2aa0b17 Mon Sep 17 00:00:00 2001
From: Carter Jernigan <git@carterjernigan.com>
Date: Thu, 16 Jun 2022 07:39:45 -0400
Subject: [PATCH] [#493] Warn when running under Rosetta

---
 .../secant.rosetta-conventions.gradle.kts     | 47 +++++++++++++++++++
 build.gradle.kts                              |  1 +
 2 files changed, 48 insertions(+)
 create mode 100644 build-conventions-secant/src/main/kotlin/secant.rosetta-conventions.gradle.kts

diff --git a/build-conventions-secant/src/main/kotlin/secant.rosetta-conventions.gradle.kts b/build-conventions-secant/src/main/kotlin/secant.rosetta-conventions.gradle.kts
new file mode 100644
index 00000000..c5988b4f
--- /dev/null
+++ b/build-conventions-secant/src/main/kotlin/secant.rosetta-conventions.gradle.kts
@@ -0,0 +1,47 @@
+import java.util.concurrent.TimeUnit
+if (isRosetta()) {
+    logger.warn("This Gradle invocation is running under Rosetta. Use an ARM (aarch64) JDK to " +
+        "improve performance. One can be downloaded from https://adoptium.net/temurin/releases")
+}
+
+@Suppress("MagicNumber")
+private val maxTimeoutMillis = 5000L
+
+/**
+ * This method is safe to call from any operating system or CPU architecture.
+ *
+ * @return True if the application is running under Rosetta.
+ */
+fun isRosetta(): Boolean {
+    if (System.getProperty("os.name").toLowerCase(java.util.Locale.ROOT).startsWith("mac")) {
+        // Counterintuitive, but running under Rosetta is reported as Intel64 to the JVM
+        if (!System.getProperty("os.arch").toLowerCase(java.util.Locale.ROOT).contains("aarch64")) {
+            val outputValue = Runtime.getRuntime()
+                .exec("sysctl -in sysctl.proc_translated")
+                .scanOutputLine()
+                ?.toIntOrNull()
+
+            if (1 == outputValue) {
+                return true
+            }
+        }
+    }
+
+    return false
+}
+
+fun Process.scanOutputLine(): String? {
+    var outputString = ""
+
+    inputStream.use { inputStream ->
+        java.util.Scanner(inputStream).useDelimiter("\\A").use { scanner ->
+            while (scanner.hasNext()) {
+                outputString = scanner.next()
+            }
+        }
+    }
+
+    waitFor(maxTimeoutMillis, TimeUnit.MILLISECONDS)
+
+    return outputString.trim()
+}
diff --git a/build.gradle.kts b/build.gradle.kts
index e266d615..39dcdc18 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -11,6 +11,7 @@ plugins {
     id("io.gitlab.arturbosch.detekt")
     id("org.jetbrains.kotlinx.kover")
     id("secant.ktlint-conventions")
+    id("secant.rosetta-conventions")
 }
 
 tasks {