From 62b8b5889d167d02db929d65f71bd6050a696f6a Mon Sep 17 00:00:00 2001
From: Jianfeng Jiang <jiangjianfeng.jjf@antgroup.com>
Date: Tue, 27 Sep 2022 14:17:19 +0800
Subject: [PATCH] fix copy_bom error message if rsync is not installed

---
 tools/copy_bom/src/error.rs |  3 ++-
 tools/copy_bom/src/main.rs  |  2 ++
 tools/copy_bom/src/util.rs  | 22 ++++++++++++++++++++--
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/tools/copy_bom/src/error.rs b/tools/copy_bom/src/error.rs
index 2dec2e67..7d345c94 100644
--- a/tools/copy_bom/src/error.rs
+++ b/tools/copy_bom/src/error.rs
@@ -1,4 +1,4 @@
-/// This file defines error number to indicate different errors
+//! This file defines error number to indicate different errors
 pub static FILE_NOT_EXISTS_ERROR: i32 = -1;
 pub static COPY_FILE_ERROR: i32 = -2;
 pub static INVALID_BOM_FILE_ERROR: i32 = -3;
@@ -7,3 +7,4 @@ pub static CREATE_SYMLINK_ERROR: i32 = -5;
 pub static COPY_DIR_ERROR: i32 = -6;
 pub static INCORRECT_HASH_ERROR: i32 = -7;
 pub static MISSING_LIBRARY_ERROR: i32 = -8;
+pub static RSYNC_NOT_FOUND_ERROR: i32 = -9;
diff --git a/tools/copy_bom/src/main.rs b/tools/copy_bom/src/main.rs
index c3cf4de6..70fe6850 100644
--- a/tools/copy_bom/src/main.rs
+++ b/tools/copy_bom/src/main.rs
@@ -10,6 +10,7 @@ extern crate walkdir;
 use bom::Bom;
 use env_logger::Env;
 use structopt::StructOpt;
+use util::check_rsync;
 
 mod bom;
 mod error;
@@ -49,6 +50,7 @@ fn main() {
     // the copy_bom log environmental variable
     let env = Env::new().filter("OCCLUM_LOG_LEVEL");
     env_logger::init_from_env(env);
+    check_rsync();
 
     let copy_bom_option = CopyBomOption::from_args();
     copy_bom_option.copy_files();
diff --git a/tools/copy_bom/src/util.rs b/tools/copy_bom/src/util.rs
index d3c296ee..ca647edb 100644
--- a/tools/copy_bom/src/util.rs
+++ b/tools/copy_bom/src/util.rs
@@ -1,6 +1,6 @@
 use crate::error::{
     COPY_DIR_ERROR, COPY_FILE_ERROR, CREATE_DIR_ERROR, CREATE_SYMLINK_ERROR, FILE_NOT_EXISTS_ERROR,
-    INCORRECT_HASH_ERROR, MISSING_LIBRARY_ERROR,
+    INCORRECT_HASH_ERROR, MISSING_LIBRARY_ERROR, RSYNC_NOT_FOUND_ERROR,
 };
 use data_encoding::HEXUPPER;
 use elf::types::{Type, ET_DYN, ET_EXEC};
@@ -8,7 +8,7 @@ use regex::Regex;
 use sha2::{Digest, Sha256};
 use std::collections::{HashMap, HashSet};
 use std::path::PathBuf;
-use std::process::{Command, Output};
+use std::process::{Command, Output, Stdio};
 use std::sync::Mutex;
 use std::vec;
 
@@ -598,3 +598,21 @@ pub fn warn_on_nonempty_image_dir(image_dir: &str) {
         }
     }
 }
+
+/// Check rsync is installed by running command `rsync --version`.
+/// The exit code should be zero if rsync is installed.
+/// If rsync is not installed, copy_bom will abort.
+pub fn check_rsync() {
+    let mut command = Command::new("rsync");
+    command.arg("--version");
+    command.stdout(Stdio::null());
+    if let Ok(status) = command.status() {
+        if let Some(exit_code) = status.code() {
+            if exit_code == 0 {
+                return;
+            }
+        }
+    }
+    println!("rsync is not installed.");
+    std::process::exit(RSYNC_NOT_FOUND_ERROR);
+}