From dff54fd8533555c8db5ca71055160cad69ba31e2 Mon Sep 17 00:00:00 2001
From: "K.G. Wang" <wkgcass@hotmail.com>
Date: Sun, 21 Jul 2024 02:25:22 +0800
Subject: [PATCH] [os] detect shell charset

---
 .../src/main/java/io/vproxy/base/util/OS.java | 73 +++++++++++++++++++
 .../main/java/io/vproxy/base/util/Utils.java  | 11 ++-
 2 files changed, 80 insertions(+), 4 deletions(-)

diff --git a/base/src/main/java/io/vproxy/base/util/OS.java b/base/src/main/java/io/vproxy/base/util/OS.java
index d027a84d..e0a3398b 100644
--- a/base/src/main/java/io/vproxy/base/util/OS.java
+++ b/base/src/main/java/io/vproxy/base/util/OS.java
@@ -1,5 +1,10 @@
 package io.vproxy.base.util;
 
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
+import java.util.concurrent.TimeUnit;
+
 public class OS {
     private static final String osname;
     private static final String osversion;
@@ -79,4 +84,72 @@ public static boolean isLinux() {
     public static String arch() {
         return arch;
     }
+
+    private static Charset SHELL_CHARSET = null;
+
+    public static Charset shellCharset() {
+        if (SHELL_CHARSET != null) {
+            return SHELL_CHARSET;
+        }
+        var charsets = new ArrayList<Charset>();
+        charsets.add(StandardCharsets.UTF_8);
+        try {
+            charsets.add(Charset.forName("GBK"));
+        } catch (Throwable ignore) {
+        }
+        //noinspection UnnecessaryUnicodeEscape
+        var testStr = "\u4F60\u597D\uFF0C\u4E16\u754C"; // 你好，世界
+        String cmd;
+        if (isWindows()) {
+            cmd = "echo " + testStr;
+        } else {
+            cmd = "echo \"" + testStr + "\"";
+        }
+        for (var c : charsets) {
+            var s = new String(cmd.getBytes(c), c);
+            ProcessBuilder pb;
+            if (isWindows()) {
+                pb = new ProcessBuilder("cmd.exe", "/c", s);
+            } else {
+                pb = new ProcessBuilder("/bin/sh", "-c", s);
+            }
+            int exitCode;
+            String stdout;
+            String stderr;
+            try {
+                var p = pb.start();
+                var ok = p.waitFor(500, TimeUnit.MILLISECONDS);
+                if (!ok) {
+                    Logger.warn(LogType.SYS_ERROR, "failed executing cmd: " + cmd + ", command didn't finish in 500ms");
+                    try {
+                        p.destroyForcibly();
+                    } catch (Throwable ignore) {
+                    }
+                    continue;
+                }
+                exitCode = p.exitValue();
+                stdout = new String(p.getInputStream().readAllBytes(), c);
+                stderr = new String(p.getErrorStream().readAllBytes(), c);
+            } catch (Exception e) {
+                Logger.warn(LogType.SYS_ERROR, "failed executing cmd: " + cmd, e);
+                continue;
+            }
+            if (exitCode != 0) {
+                Logger.warn(LogType.SYS_ERROR, "failed executing cmd: " + cmd + ", exitCode = " + exitCode +
+                    ", stdout = " + stdout + ", stderr = " + stderr);
+                continue;
+            }
+            stdout = stdout.trim();
+            if (testStr.equals(stdout)) {
+                Logger.alert("shell charset is determined: " + c + ", getting result: " + stdout);
+                SHELL_CHARSET = c;
+                return c;
+            } else {
+                Logger.warn(LogType.ALERT, "shell charset is not " + c + ", getting result: `" + stdout + "`");
+            }
+        }
+        Logger.warn(LogType.ALERT, "shell charset cannot be determined, using UTF-8 by default");
+        SHELL_CHARSET = StandardCharsets.UTF_8;
+        return SHELL_CHARSET;
+    }
 }
diff --git a/base/src/main/java/io/vproxy/base/util/Utils.java b/base/src/main/java/io/vproxy/base/util/Utils.java
index 4d000d27..3c0084db 100644
--- a/base/src/main/java/io/vproxy/base/util/Utils.java
+++ b/base/src/main/java/io/vproxy/base/util/Utils.java
@@ -599,15 +599,18 @@ public static ExecuteResult execute(String script, int timeout, boolean getResul
         }
         File file = File.createTempFile("script", OS.isWindows() ? ".bat" : ".sh");
         try {
-            Files.writeString(file.toPath(), script);
+            script = "@echo off\r\n" + script;
+            Files.writeString(file.toPath(), script, OS.shellCharset());
             if (!file.setExecutable(true)) {
-                throw new Exception("setting executable to script " + file.getAbsolutePath() + " failed");
+                throw new Exception("chmod +x " + file.getAbsolutePath() + " failed");
             }
+            var filePath = file.getAbsolutePath();
+            filePath = new String(filePath.getBytes(OS.shellCharset()), OS.shellCharset());
             ProcessBuilder pb;
             if (OS.isWindows()) {
-                pb = new ProcessBuilder("cmd.exe", "/c", file.getAbsolutePath());
+                pb = new ProcessBuilder("cmd.exe", "/c", filePath);
             } else {
-                pb = new ProcessBuilder(file.getAbsolutePath());
+                pb = new ProcessBuilder(filePath);
             }
             return execute(pb, timeout, getResult);
         } finally {