From 16cccf1261bc916f951de5819160b3d4b724f314 Mon Sep 17 00:00:00 2001
From: HuijingHei <hhei@redhat.com>
Date: Thu, 11 Jul 2024 18:55:59 +0800
Subject: [PATCH] filetree: add failpoint when doing exchange

Inspired by https://github.com/coreos/bootupd/pull/669#issuecomment-2220760948
---
 Cargo.lock                           | 53 ++++++++++++++++++++++++++++
 src/bootupd.rs                       | 15 ++++++++
 src/failpoints.rs                    | 21 +++++++++++
 src/filetree.rs                      |  2 +-
 src/main.rs                          |  2 ++
 tests/e2e-update/e2e-update-in-vm.sh |  7 +++-
 tests/e2e-update/e2e-update.sh       |  8 +++--
 7 files changed, 104 insertions(+), 4 deletions(-)
 create mode 100644 src/failpoints.rs

diff --git a/Cargo.lock b/Cargo.lock
index 2cbaafb9..6498eb3b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -82,6 +82,7 @@ dependencies = [
  "bincode",
  "cap-std-ext",
  "camino",
+ "cap-std-ext",
  "chrono",
  "clap",
  "env_logger",
@@ -167,6 +168,58 @@ version = "1.1.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e0ec6b951b160caa93cc0c7b209e5a3bff7aae9062213451ac99493cd844c239"
 
+[[package]]
+name = "cap-primitives"
+version = "3.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6d00bd8d26c4270d950eaaa837387964a2089a1c3c349a690a1fa03221d29531"
+dependencies = [
+ "ambient-authority",
+ "fs-set-times",
+ "io-extras",
+ "io-lifetimes",
+ "ipnet",
+ "maybe-owned",
+ "rustix",
+ "windows-sys 0.52.0",
+ "winx",
+]
+
+[[package]]
+name = "cap-std"
+version = "3.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "19eb8e3d71996828751c1ed3908a439639752ac6bdc874e41469ef7fc15fbd7f"
+dependencies = [
+ "cap-primitives",
+ "io-extras",
+ "io-lifetimes",
+ "rustix",
+]
+
+[[package]]
+name = "cap-std-ext"
+version = "4.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d0279cf1f7b6cbeeb98e6946e8fea58136f691d4d0aa8c775f4439a05030a481"
+dependencies = [
+ "cap-primitives",
+ "cap-tempfile",
+ "rustix",
+]
+
+[[package]]
+name = "cap-tempfile"
+version = "3.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "53880047c3f37cd64947775f0526795498d614182603a718c792616b762ce777"
+dependencies = [
+ "cap-std",
+ "rand",
+ "rustix",
+ "uuid",
+]
+
 [[package]]
 name = "cc"
 version = "1.0.83"
diff --git a/src/bootupd.rs b/src/bootupd.rs
index 72d025d0..4f029e83 100644
--- a/src/bootupd.rs
+++ b/src/bootupd.rs
@@ -396,6 +396,7 @@ pub(crate) fn print_status(status: &Status) -> Result<()> {
 }
 
 pub(crate) fn client_run_update() -> Result<()> {
+    crate::try_fail_point!("update");
     let status: Status = status()?;
     if status.components.is_empty() && status.adoptable.is_empty() {
         println!("No components installed.");
@@ -489,3 +490,17 @@ pub(crate) fn client_run_validate() -> Result<()> {
     }
     Ok(())
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_failpoint_update() {
+        let guard = fail::FailScenario::setup();
+        fail::cfg("update", "return").unwrap();
+        let r = client_run_update();
+        assert_eq!(r.is_err(), true);
+        guard.teardown();
+    }
+}
diff --git a/src/failpoints.rs b/src/failpoints.rs
new file mode 100644
index 00000000..78dce44f
--- /dev/null
+++ b/src/failpoints.rs
@@ -0,0 +1,21 @@
+//! Wrappers and utilities on top of the `fail` crate.
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
+/// TODO: Use https://github.com/tikv/fail-rs/pull/68 once it merges
+/// copy from https://github.com/coreos/rpm-ostree/commit/aa8d7fb0ceaabfaf10252180e2ddee049d07aae3#diff-adcc419e139605fae34d17b31418dbaf515af2fe9fb766fcbdb2eaad862b3daa
+#[macro_export]
+macro_rules! try_fail_point {
+    ($name:expr) => {{
+        if let Some(e) = fail::eval($name, |msg| {
+            let msg = msg.unwrap_or_else(|| "synthetic failpoint".to_string());
+            anyhow::Error::msg(msg)
+        }) {
+            return Err(From::from(e));
+        }
+    }};
+    ($name:expr, $cond:expr) => {{
+        if $cond {
+            $crate::try_fail_point!($name);
+        }
+    }};
+}
diff --git a/src/filetree.rs b/src/filetree.rs
index 047ca384..8234dcba 100644
--- a/src/filetree.rs
+++ b/src/filetree.rs
@@ -395,6 +395,7 @@ pub(crate) fn apply_diff(
                 .local_rename(tmp, dst)
                 .with_context(|| format!("rename for {} and {:?}", tmp, dst))?;
         }
+        crate::try_fail_point!("update::exchange");
     }
     // Ensure all of the updates & changes are written persistently to disk
     if !opts.skip_sync {
@@ -705,7 +706,6 @@ mod tests {
             let b_btime_foo_new = fs::metadata(pb.join(foo))?.created()?;
             assert_eq!(b_btime_foo_new, b_btime_foo);
         }
-
         Ok(())
     }
 }
diff --git a/src/main.rs b/src/main.rs
index b075bde0..7c7cb40c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -24,6 +24,7 @@ mod component;
 mod coreos;
 #[cfg(any(target_arch = "x86_64", target_arch = "aarch64"))]
 mod efi;
+mod failpoints;
 mod filesystem;
 mod filetree;
 #[cfg(any(
@@ -43,6 +44,7 @@ use clap::crate_name;
 
 /// Binary entrypoint, for both daemon and client logic.
 fn main() {
+    let _scenario = fail::FailScenario::setup();
     let exit_code = run_cli();
     std::process::exit(exit_code);
 }
diff --git a/tests/e2e-update/e2e-update-in-vm.sh b/tests/e2e-update/e2e-update-in-vm.sh
index fd969cad..0956bdfa 100755
--- a/tests/e2e-update/e2e-update-in-vm.sh
+++ b/tests/e2e-update/e2e-update-in-vm.sh
@@ -67,7 +67,12 @@ tmpefimount=$(mount_tmp_efi)
 
 assert_not_has_file ${tmpefimount}/EFI/fedora/test-bootupd.efi
 
-bootupctl update | tee out.txt
+if env FAILPOINTS='update::exchange=return' bootupctl update -vvv 2>err.txt; then
+    fatal "should have errored"
+fi
+assert_file_has_content err.txt "error: .*synthetic failpoint"
+
+bootupctl update -vvv | tee out.txt
 assert_file_has_content out.txt "Previous EFI: .*"
 assert_file_has_content out.txt "Updated EFI: ${TARGET_GRUB_PKG}.*,test-bootupd-payload-1.0"
 
diff --git a/tests/e2e-update/e2e-update.sh b/tests/e2e-update/e2e-update.sh
index e45623f7..5fc19e87 100755
--- a/tests/e2e-update/e2e-update.sh
+++ b/tests/e2e-update/e2e-update.sh
@@ -24,10 +24,14 @@ export test_tmpdir=${testtmp}
 
 # This is new content for our update
 test_bootupd_payload_file=/boot/efi/EFI/fedora/test-bootupd.efi
+test_bootupd_payload_file1=/boot/efi/EFI/BOOT/test-bootupd1.efi
 build_rpm test-bootupd-payload \
-  files ${test_bootupd_payload_file} \
+  files "${test_bootupd_payload_file}
+         ${test_bootupd_payload_file1}" \
   install "mkdir -p %{buildroot}/$(dirname ${test_bootupd_payload_file})
-           echo test-payload > %{buildroot}/${test_bootupd_payload_file}"
+           echo test-payload > %{buildroot}/${test_bootupd_payload_file}
+           mkdir -p %{buildroot}/$(dirname ${test_bootupd_payload_file1})
+           echo test-payload1 > %{buildroot}/${test_bootupd_payload_file1}"
 
 # Start in cosa dir
 cd ${COSA_DIR}