Implement susped, resume and cancel for the Postinstall action.
This patch sends SIGSTOP/SIGCONT to the running postinstall program to
suspend/resume the child process, and SIGKILL when cancelling it.
Bug: 27272144
TEST=Added unittest to check the signal being sent.
Change-Id: Iebe9bd34448ad1d0a5340c82e1fd839ff8c69dd2
diff --git a/payload_consumer/postinstall_runner_action.cc b/payload_consumer/postinstall_runner_action.cc
index 9ebef53..7fa7009 100644
--- a/payload_consumer/postinstall_runner_action.cc
+++ b/payload_consumer/postinstall_runner_action.cc
@@ -16,13 +16,15 @@
#include "update_engine/payload_consumer/postinstall_runner_action.h"
+#include <signal.h>
#include <stdlib.h>
#include <sys/mount.h>
+#include <sys/types.h>
#include <vector>
-#include <base/bind.h>
#include <base/files/file_path.h>
#include <base/files/file_util.h>
+#include <base/logging.h>
#include <base/strings/string_util.h>
#include "update_engine/common/action_processor.h"
@@ -126,25 +128,31 @@
// Runs the postinstall script asynchronously to free up the main loop while
// it's running.
vector<string> command = {abs_path, partition.target_path};
- if (!Subprocess::Get().Exec(
- command,
- base::Bind(
- &PostinstallRunnerAction::CompletePartitionPostinstall,
- base::Unretained(this)))) {
+ current_command_ = Subprocess::Get().Exec(
+ command,
+ base::Bind(&PostinstallRunnerAction::CompletePartitionPostinstall,
+ base::Unretained(this)));
+ // Subprocess::Exec should never return a negative process id.
+ CHECK_GE(current_command_, 0);
+
+ if (!current_command_)
CompletePartitionPostinstall(1, "Postinstall didn't launch");
- }
}
-void PostinstallRunnerAction::CompletePartitionPostinstall(
- int return_code,
- const string& output) {
+void PostinstallRunnerAction::CleanupMount() {
utils::UnmountFilesystem(fs_mount_dir_);
-#ifndef ANDROID
+#ifndef __ANDROID__
if (!base::DeleteFile(base::FilePath(fs_mount_dir_), false)) {
PLOG(WARNING) << "Not removing temporary mountpoint " << fs_mount_dir_;
}
-#endif // !ANDROID
+#endif // !__ANDROID__
fs_mount_dir_.clear();
+}
+
+void PostinstallRunnerAction::CompletePartitionPostinstall(
+ int return_code, const string& output) {
+ current_command_ = 0;
+ CleanupMount();
if (return_code != 0) {
LOG(ERROR) << "Postinst command failed with code: " << return_code;
@@ -196,4 +204,30 @@
}
}
+void PostinstallRunnerAction::SuspendAction() {
+ if (!current_command_)
+ return;
+ if (kill(current_command_, SIGSTOP) != 0) {
+ PLOG(ERROR) << "Couldn't pause child process " << current_command_;
+ }
+}
+
+void PostinstallRunnerAction::ResumeAction() {
+ if (!current_command_)
+ return;
+ if (kill(current_command_, SIGCONT) != 0) {
+ PLOG(ERROR) << "Couldn't resume child process " << current_command_;
+ }
+}
+
+void PostinstallRunnerAction::TerminateProcessing() {
+ if (!current_command_)
+ return;
+ // Calling KillExec() will discard the callback we registered and therefore
+ // the unretained reference to this object.
+ Subprocess::Get().KillExec(current_command_);
+ current_command_ = 0;
+ CleanupMount();
+}
+
} // namespace chromeos_update_engine