Move result.h from init to libbase
The Result, Error, ErrnoError are quite generic. Moving them from init
to libbase so that they can be used from other places.
Bug: 132145659
Test: libbase_test
Change-Id: Id774a587f74380fadd7a0fc88c0aa892c3d9a489
diff --git a/init/Android.bp b/init/Android.bp
index eaa7fd7..fa0a35c 100644
--- a/init/Android.bp
+++ b/init/Android.bp
@@ -190,7 +190,6 @@
"persistent_properties_test.cpp",
"property_service_test.cpp",
"property_type_test.cpp",
- "result_test.cpp",
"rlimit_parser_test.cpp",
"service_test.cpp",
"subcontext_test.cpp",
diff --git a/init/action.cpp b/init/action.cpp
index a4f6936..a40172e 100644
--- a/init/action.cpp
+++ b/init/action.cpp
@@ -127,7 +127,7 @@
// report such failures unless we're running at the DEBUG log level.
bool report_failure = !result.has_value();
if (report_failure && android::base::GetMinimumLogSeverity() > android::base::DEBUG &&
- result.error().as_errno == ENOENT) {
+ result.error().code() == ENOENT) {
report_failure = false;
}
@@ -139,7 +139,7 @@
LOG(INFO) << "Command '" << cmd_str << "' action=" << trigger_name << " (" << filename_
<< ":" << command.line() << ") took " << duration.count() << "ms and "
- << (result ? "succeeded" : "failed: " + result.error().as_string);
+ << (result ? "succeeded" : "failed: " + result.error().message());
}
}
diff --git a/init/result.h b/init/result.h
index baa680d..984b257 100644
--- a/init/result.h
+++ b/init/result.h
@@ -29,8 +29,8 @@
// string value.
//
// Success is a typedef that aids in creating Result<T> that do not contain a return value.
-// Result<Success> is the correct return type for a function that either returns successfully or
-// returns an error value. Returning Success() from a function that returns Result<Success> is the
+// Result<Nothing> is the correct return type for a function that either returns successfully or
+// returns an error value. Returning Nothing() from a function that returns Result<Nothing> is the
// correct way to indicate that a function without a return type has completed successfully.
//
// A successful Result<T> is constructed implicitly from any type that can be implicitly converted
@@ -70,101 +70,10 @@
#pragma once
-#include <errno.h>
+#include <android-base/result.h>
-#include <sstream>
-#include <string>
-
-#include <android-base/expected.h>
-
-namespace android {
-namespace init {
-
-struct ResultError {
- template <typename T>
- ResultError(T&& error_string, int error_errno)
- : as_string(std::forward<T>(error_string)), as_errno(error_errno) {}
-
- template <typename T>
- operator android::base::expected<T, ResultError>() {
- return android::base::unexpected(ResultError(as_string, as_errno));
- }
-
- std::string as_string;
- int as_errno;
-};
-
-inline std::ostream& operator<<(std::ostream& os, const ResultError& t) {
- os << t.as_string;
- return os;
-}
-
-inline std::ostream& operator<<(std::ostream& os, ResultError&& t) {
- os << std::move(t.as_string);
- return os;
-}
-
-class Error {
- public:
- Error() : errno_(0), append_errno_(false) {}
- Error(int errno_to_append) : errno_(errno_to_append), append_errno_(true) {}
-
- template <typename T>
- operator android::base::expected<T, ResultError>() {
- return android::base::unexpected(ResultError(str(), errno_));
- }
-
- template <typename T>
- Error&& operator<<(T&& t) {
- ss_ << std::forward<T>(t);
- return std::move(*this);
- }
-
- Error&& operator<<(const ResultError& result_error) {
- ss_ << result_error.as_string;
- errno_ = result_error.as_errno;
- return std::move(*this);
- }
-
- Error&& operator<<(ResultError&& result_error) {
- ss_ << std::move(result_error.as_string);
- errno_ = result_error.as_errno;
- return std::move(*this);
- }
-
- const std::string str() const {
- std::string str = ss_.str();
- if (append_errno_) {
- if (str.empty()) {
- return strerror(errno_);
- }
- return str + ": " + strerror(errno_);
- }
- return str;
- }
-
- int get_errno() const { return errno_; }
-
- Error(const Error&) = delete;
- Error(Error&&) = delete;
- Error& operator=(const Error&) = delete;
- Error& operator=(Error&&) = delete;
-
- private:
- std::stringstream ss_;
- int errno_;
- bool append_errno_;
-};
-
-inline Error ErrnoError() {
- return Error(errno);
-}
-
-template <typename T>
-using Result = android::base::expected<T, ResultError>;
-
-using Success = std::monostate;
-
-} // namespace init
-} // namespace android
-
+using android::base::ErrnoError;
+using android::base::Error;
+using android::base::Result;
+using android::base::ResultError;
+using android::base::Success;
diff --git a/init/result_test.cpp b/init/result_test.cpp
deleted file mode 100644
index d3d04a0..0000000
--- a/init/result_test.cpp
+++ /dev/null
@@ -1,335 +0,0 @@
-/*
- * Copyright (C) 2017 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "result.h"
-
-#include "errno.h"
-
-#include <string>
-
-#include <gtest/gtest.h>
-
-using namespace std::string_literals;
-
-namespace android {
-namespace init {
-
-TEST(result, result_accessors) {
- Result<std::string> result = "success";
- ASSERT_TRUE(result);
- ASSERT_TRUE(result.has_value());
-
- EXPECT_EQ("success", *result);
- EXPECT_EQ("success", result.value());
-
- EXPECT_EQ('s', result->data()[0]);
-}
-
-TEST(result, result_accessors_rvalue) {
- ASSERT_TRUE(Result<std::string>("success"));
- ASSERT_TRUE(Result<std::string>("success").has_value());
-
- EXPECT_EQ("success", *Result<std::string>("success"));
- EXPECT_EQ("success", Result<std::string>("success").value());
-
- EXPECT_EQ('s', Result<std::string>("success")->data()[0]);
-}
-
-TEST(result, result_success) {
- Result<Success> result = Success();
- ASSERT_TRUE(result);
- ASSERT_TRUE(result.has_value());
-
- EXPECT_EQ(Success(), *result);
- EXPECT_EQ(Success(), result.value());
-}
-
-TEST(result, result_success_rvalue) {
- // Success() doesn't actually create a Result<Success> object, but rather an object that can be
- // implicitly constructed into a Result<Success> object.
-
- auto MakeRvalueSuccessResult = []() -> Result<Success> { return Success(); };
- ASSERT_TRUE(MakeRvalueSuccessResult());
- ASSERT_TRUE(MakeRvalueSuccessResult().has_value());
-
- EXPECT_EQ(Success(), *MakeRvalueSuccessResult());
- EXPECT_EQ(Success(), MakeRvalueSuccessResult().value());
-}
-
-TEST(result, result_error) {
- Result<Success> result = Error() << "failure" << 1;
- ASSERT_FALSE(result);
- ASSERT_FALSE(result.has_value());
-
- EXPECT_EQ(0, result.error().as_errno);
- EXPECT_EQ("failure1", result.error().as_string);
-}
-
-TEST(result, result_error_empty) {
- Result<Success> result = Error();
- ASSERT_FALSE(result);
- ASSERT_FALSE(result.has_value());
-
- EXPECT_EQ(0, result.error().as_errno);
- EXPECT_EQ("", result.error().as_string);
-}
-
-TEST(result, result_error_rvalue) {
- // Error() and ErrnoError() aren't actually used to create a Result<T> object.
- // Under the hood, they are an intermediate class that can be implicitly constructed into a
- // Result<T>. This is needed both to create the ostream and because Error() itself, by
- // definition will not know what the type, T, of the underlying Result<T> object that it would
- // create is.
-
- auto MakeRvalueErrorResult = []() -> Result<Success> { return Error() << "failure" << 1; };
- ASSERT_FALSE(MakeRvalueErrorResult());
- ASSERT_FALSE(MakeRvalueErrorResult().has_value());
-
- EXPECT_EQ(0, MakeRvalueErrorResult().error().as_errno);
- EXPECT_EQ("failure1", MakeRvalueErrorResult().error().as_string);
-}
-
-TEST(result, result_errno_error) {
- constexpr int test_errno = 6;
- errno = test_errno;
- Result<Success> result = ErrnoError() << "failure" << 1;
-
- ASSERT_FALSE(result);
- ASSERT_FALSE(result.has_value());
-
- EXPECT_EQ(test_errno, result.error().as_errno);
- EXPECT_EQ("failure1: "s + strerror(test_errno), result.error().as_string);
-}
-
-TEST(result, result_errno_error_no_text) {
- constexpr int test_errno = 6;
- errno = test_errno;
- Result<Success> result = ErrnoError();
-
- ASSERT_FALSE(result);
- ASSERT_FALSE(result.has_value());
-
- EXPECT_EQ(test_errno, result.error().as_errno);
- EXPECT_EQ(strerror(test_errno), result.error().as_string);
-}
-
-TEST(result, result_error_from_other_result) {
- auto error_text = "test error"s;
- Result<Success> result = Error() << error_text;
-
- ASSERT_FALSE(result);
- ASSERT_FALSE(result.has_value());
-
- Result<std::string> result2 = result.error();
-
- ASSERT_FALSE(result2);
- ASSERT_FALSE(result2.has_value());
-
- EXPECT_EQ(0, result.error().as_errno);
- EXPECT_EQ(error_text, result.error().as_string);
-}
-
-TEST(result, result_error_through_ostream) {
- auto error_text = "test error"s;
- Result<Success> result = Error() << error_text;
-
- ASSERT_FALSE(result);
- ASSERT_FALSE(result.has_value());
-
- Result<std::string> result2 = Error() << result.error();
-
- ASSERT_FALSE(result2);
- ASSERT_FALSE(result2.has_value());
-
- EXPECT_EQ(0, result.error().as_errno);
- EXPECT_EQ(error_text, result.error().as_string);
-}
-
-TEST(result, result_errno_error_through_ostream) {
- auto error_text = "test error"s;
- constexpr int test_errno = 6;
- errno = 6;
- Result<Success> result = ErrnoError() << error_text;
-
- errno = 0;
-
- ASSERT_FALSE(result);
- ASSERT_FALSE(result.has_value());
-
- Result<std::string> result2 = Error() << result.error();
-
- ASSERT_FALSE(result2);
- ASSERT_FALSE(result2.has_value());
-
- EXPECT_EQ(test_errno, result.error().as_errno);
- EXPECT_EQ(error_text + ": " + strerror(test_errno), result.error().as_string);
-}
-
-TEST(result, constructor_forwarding) {
- auto result = Result<std::string>(std::in_place, 5, 'a');
-
- ASSERT_TRUE(result);
- ASSERT_TRUE(result.has_value());
-
- EXPECT_EQ("aaaaa", *result);
-}
-
-struct ConstructorTracker {
- static size_t constructor_called;
- static size_t copy_constructor_called;
- static size_t move_constructor_called;
- static size_t copy_assignment_called;
- static size_t move_assignment_called;
-
- template <typename T>
- ConstructorTracker(T&& string) : string(string) {
- ++constructor_called;
- }
-
- ConstructorTracker(const ConstructorTracker& ct) {
- ++copy_constructor_called;
- string = ct.string;
- }
- ConstructorTracker(ConstructorTracker&& ct) noexcept {
- ++move_constructor_called;
- string = std::move(ct.string);
- }
- ConstructorTracker& operator=(const ConstructorTracker& ct) {
- ++copy_assignment_called;
- string = ct.string;
- return *this;
- }
- ConstructorTracker& operator=(ConstructorTracker&& ct) noexcept {
- ++move_assignment_called;
- string = std::move(ct.string);
- return *this;
- }
-
- std::string string;
-};
-
-size_t ConstructorTracker::constructor_called = 0;
-size_t ConstructorTracker::copy_constructor_called = 0;
-size_t ConstructorTracker::move_constructor_called = 0;
-size_t ConstructorTracker::copy_assignment_called = 0;
-size_t ConstructorTracker::move_assignment_called = 0;
-
-Result<ConstructorTracker> ReturnConstructorTracker(const std::string& in) {
- if (in.empty()) {
- return "literal string";
- }
- if (in == "test2") {
- return ConstructorTracker(in + in + "2");
- }
- ConstructorTracker result(in + " " + in);
- return result;
-};
-
-TEST(result, no_copy_on_return) {
- // If returning parameters that may be used to implicitly construct the type T of Result<T>,
- // then those parameters are forwarded to the construction of Result<T>.
-
- // If returning an prvalue or xvalue, it will be move constructed during the construction of
- // Result<T>.
-
- // This check ensures that that is the case, and particularly that no copy constructors
- // are called.
-
- auto result1 = ReturnConstructorTracker("");
- ASSERT_TRUE(result1);
- EXPECT_EQ("literal string", result1->string);
- EXPECT_EQ(1U, ConstructorTracker::constructor_called);
- EXPECT_EQ(0U, ConstructorTracker::copy_constructor_called);
- EXPECT_EQ(0U, ConstructorTracker::move_constructor_called);
- EXPECT_EQ(0U, ConstructorTracker::copy_assignment_called);
- EXPECT_EQ(0U, ConstructorTracker::move_assignment_called);
-
- auto result2 = ReturnConstructorTracker("test2");
- ASSERT_TRUE(result2);
- EXPECT_EQ("test2test22", result2->string);
- EXPECT_EQ(2U, ConstructorTracker::constructor_called);
- EXPECT_EQ(0U, ConstructorTracker::copy_constructor_called);
- EXPECT_EQ(1U, ConstructorTracker::move_constructor_called);
- EXPECT_EQ(0U, ConstructorTracker::copy_assignment_called);
- EXPECT_EQ(0U, ConstructorTracker::move_assignment_called);
-
- auto result3 = ReturnConstructorTracker("test3");
- ASSERT_TRUE(result3);
- EXPECT_EQ("test3 test3", result3->string);
- EXPECT_EQ(3U, ConstructorTracker::constructor_called);
- EXPECT_EQ(0U, ConstructorTracker::copy_constructor_called);
- EXPECT_EQ(2U, ConstructorTracker::move_constructor_called);
- EXPECT_EQ(0U, ConstructorTracker::copy_assignment_called);
- EXPECT_EQ(0U, ConstructorTracker::move_assignment_called);
-}
-
-// Below two tests require that we do not hide the move constructor with our forwarding reference
-// constructor. This is done with by disabling the forwarding reference constructor if its first
-// and only type is Result<T>.
-TEST(result, result_result_with_success) {
- auto return_result_result_with_success = []() -> Result<Result<Success>> {
- return Result<Success>();
- };
- auto result = return_result_result_with_success();
- ASSERT_TRUE(result);
- ASSERT_TRUE(*result);
-
- auto inner_result = result.value();
- ASSERT_TRUE(inner_result);
-}
-
-TEST(result, result_result_with_failure) {
- auto return_result_result_with_error = []() -> Result<Result<Success>> {
- return Result<Success>(ResultError("failure string", 6));
- };
- auto result = return_result_result_with_error();
- ASSERT_TRUE(result);
- ASSERT_FALSE(*result);
- EXPECT_EQ("failure string", (*result).error().as_string);
- EXPECT_EQ(6, (*result).error().as_errno);
-}
-
-// This test requires that we disable the forwarding reference constructor if Result<T> is the
-// *only* type that we are forwarding. In otherwords, if we are forwarding Result<T>, int to
-// construct a Result<T>, then we still need the constructor.
-TEST(result, result_two_parameter_constructor_same_type) {
- struct TestStruct {
- TestStruct(int value) : value_(value) {}
- TestStruct(Result<TestStruct> result, int value) : value_(result->value_ * value) {}
- int value_;
- };
-
- auto return_test_struct = []() -> Result<TestStruct> {
- return Result<TestStruct>(std::in_place, Result<TestStruct>(std::in_place, 6), 6);
- };
-
- auto result = return_test_struct();
- ASSERT_TRUE(result);
- EXPECT_EQ(36, result->value_);
-}
-
-TEST(result, die_on_access_failed_result) {
- Result<std::string> result = Error();
- ASSERT_DEATH(*result, "");
-}
-
-TEST(result, die_on_get_error_succesful_result) {
- Result<std::string> result = "success";
- ASSERT_DEATH(result.error(), "");
-}
-
-} // namespace init
-} // namespace android
diff --git a/init/rlimit_parser_test.cpp b/init/rlimit_parser_test.cpp
index e690bf6..6a16d3b 100644
--- a/init/rlimit_parser_test.cpp
+++ b/init/rlimit_parser_test.cpp
@@ -43,8 +43,8 @@
auto result = ParseRlimit(input);
ASSERT_FALSE(result) << "input: " << input[1];
- EXPECT_EQ(expected_result, result.error().as_string);
- EXPECT_EQ(0, result.error().as_errno);
+ EXPECT_EQ(expected_result, result.error().message());
+ EXPECT_EQ(0, result.error().code());
}
TEST(rlimit, RlimitSuccess) {
diff --git a/init/service.cpp b/init/service.cpp
index 8fe5b30..a54cb6b 100644
--- a/init/service.cpp
+++ b/init/service.cpp
@@ -1196,7 +1196,7 @@
continue;
}
if (auto result = service->Start(); !result) {
- LOG(ERROR) << result.error().as_string;
+ LOG(ERROR) << result.error().message();
}
}
delayed_service_names_.clear();
diff --git a/init/subcontext.cpp b/init/subcontext.cpp
index f9eb83d..0ff479a 100644
--- a/init/subcontext.cpp
+++ b/init/subcontext.cpp
@@ -142,8 +142,8 @@
reply->set_success(true);
} else {
auto* failure = reply->mutable_failure();
- failure->set_error_string(result.error().as_string);
- failure->set_error_errno(result.error().as_errno);
+ failure->set_error_string(result.error().message());
+ failure->set_error_errno(result.error().code());
}
}
@@ -178,7 +178,7 @@
auto init_message = ReadMessage(init_fd_);
if (!init_message) {
- if (init_message.error().as_errno == 0) {
+ if (init_message.error().code() == 0) {
// If the init file descriptor was closed, let's exit quietly. If
// this was accidental, init will restart us. If init died, this
// avoids calling abort(3) unnecessarily.
diff --git a/init/subcontext_test.cpp b/init/subcontext_test.cpp
index c0662a4..2635683 100644
--- a/init/subcontext_test.cpp
+++ b/init/subcontext_test.cpp
@@ -69,7 +69,7 @@
auto result = subcontext.Execute(std::vector<std::string>{"return_pids_as_error"});
ASSERT_FALSE(result);
- auto pids = Split(result.error().as_string, " ");
+ auto pids = Split(result.error().message(), " ");
ASSERT_EQ(2U, pids.size());
auto our_pid = std::to_string(getpid());
EXPECT_NE(our_pid, pids[0]);
@@ -116,7 +116,7 @@
auto result = subcontext.Execute(std::vector<std::string>{"return_words_as_error"});
ASSERT_FALSE(result);
- EXPECT_EQ(Join(expected_words, " "), result.error().as_string);
+ EXPECT_EQ(Join(expected_words, " "), result.error().message());
EXPECT_EQ(first_pid, subcontext.pid());
});
}
@@ -130,7 +130,7 @@
auto result2 = subcontext.Execute(std::vector<std::string>{"generate_sane_error"});
ASSERT_FALSE(result2);
- EXPECT_EQ("Sane error!", result2.error().as_string);
+ EXPECT_EQ("Sane error!", result2.error().message());
EXPECT_NE(subcontext.pid(), first_pid);
});
}
@@ -139,7 +139,7 @@
RunTest([](auto& subcontext, auto& context_string) {
auto result = subcontext.Execute(std::vector<std::string>{"return_context_as_error"});
ASSERT_FALSE(result);
- ASSERT_EQ(context_string, result.error().as_string);
+ ASSERT_EQ(context_string, result.error().message());
});
}
@@ -167,7 +167,7 @@
};
auto result = subcontext.ExpandArgs(args);
ASSERT_FALSE(result);
- EXPECT_EQ("Failed to expand '" + args[1] + "'", result.error().as_string);
+ EXPECT_EQ("Failed to expand '" + args[1] + "'", result.error().message());
});
}
diff --git a/init/util_test.cpp b/init/util_test.cpp
index 8bf672c..8947256 100644
--- a/init/util_test.cpp
+++ b/init/util_test.cpp
@@ -34,7 +34,7 @@
auto file_contents = ReadFile("/proc/does-not-exist");
EXPECT_EQ(ENOENT, errno);
ASSERT_FALSE(file_contents);
- EXPECT_EQ("open() failed: No such file or directory", file_contents.error().as_string);
+ EXPECT_EQ("open() failed: No such file or directory", file_contents.error().message());
}
TEST(util, ReadFileGroupWriteable) {
@@ -45,7 +45,7 @@
EXPECT_NE(-1, fchmodat(AT_FDCWD, tf.path, 0620, AT_SYMLINK_NOFOLLOW)) << strerror(errno);
auto file_contents = ReadFile(tf.path);
ASSERT_FALSE(file_contents) << strerror(errno);
- EXPECT_EQ("Skipping insecure file", file_contents.error().as_string);
+ EXPECT_EQ("Skipping insecure file", file_contents.error().message());
}
TEST(util, ReadFileWorldWiteable) {
@@ -56,7 +56,7 @@
EXPECT_NE(-1, fchmodat(AT_FDCWD, tf.path, 0602, AT_SYMLINK_NOFOLLOW)) << strerror(errno);
auto file_contents = ReadFile(tf.path);
ASSERT_FALSE(file_contents) << strerror(errno);
- EXPECT_EQ("Skipping insecure file", file_contents.error().as_string);
+ EXPECT_EQ("Skipping insecure file", file_contents.error().message());
}
TEST(util, ReadFileSymbolicLink) {
@@ -66,7 +66,7 @@
EXPECT_EQ(ELOOP, errno);
ASSERT_FALSE(file_contents);
EXPECT_EQ("open() failed: Too many symbolic links encountered",
- file_contents.error().as_string);
+ file_contents.error().message());
}
TEST(util, ReadFileSuccess) {
@@ -131,7 +131,7 @@
decoded_uid = DecodeUid("toot");
EXPECT_FALSE(decoded_uid);
- EXPECT_EQ("getpwnam failed: No such file or directory", decoded_uid.error().as_string);
+ EXPECT_EQ("getpwnam failed: No such file or directory", decoded_uid.error().message());
decoded_uid = DecodeUid("123");
EXPECT_TRUE(decoded_uid);