1 // Copyright 2020 The Abseil Authors.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include "absl/base/internal/strerror.h"
16
17 #include <atomic>
18 #include <cerrno>
19 #include <cstdio>
20 #include <cstring>
21 #include <string>
22 #include <thread> // NOLINT(build/c++11)
23 #include <vector>
24
25 #include "gmock/gmock.h"
26 #include "gtest/gtest.h"
27 #include "absl/strings/match.h"
28
29 namespace {
30 using ::testing::AnyOf;
31 using ::testing::Eq;
32
TEST(StrErrorTest,ValidErrorCode)33 TEST(StrErrorTest, ValidErrorCode) {
34 errno = ERANGE;
35 EXPECT_THAT(absl::base_internal::StrError(EDOM), Eq(strerror(EDOM)));
36 EXPECT_THAT(errno, Eq(ERANGE));
37 }
38
TEST(StrErrorTest,InvalidErrorCode)39 TEST(StrErrorTest, InvalidErrorCode) {
40 errno = ERANGE;
41 EXPECT_THAT(absl::base_internal::StrError(-1),
42 AnyOf(Eq("No error information"), Eq("Unknown error -1")));
43 EXPECT_THAT(errno, Eq(ERANGE));
44 }
45
TEST(StrErrorTest,MultipleThreads)46 TEST(StrErrorTest, MultipleThreads) {
47 // In this test, we will start up 2 threads and have each one call
48 // StrError 1000 times, each time with a different errnum. We
49 // expect that StrError(errnum) will return a string equal to the
50 // one returned by strerror(errnum), if the code is known. Since
51 // strerror is known to be thread-hostile, collect all the expected
52 // strings up front.
53 const int kNumCodes = 1000;
54 std::vector<std::string> expected_strings(kNumCodes);
55 for (int i = 0; i < kNumCodes; ++i) {
56 expected_strings[i] = strerror(i);
57 }
58
59 std::atomic_int counter(0);
60 auto thread_fun = [&]() {
61 for (int i = 0; i < kNumCodes; ++i) {
62 ++counter;
63 errno = ERANGE;
64 const std::string value = absl::base_internal::StrError(i);
65 // Only the GNU implementation is guaranteed to provide the
66 // string "Unknown error nnn". POSIX doesn't say anything.
67 if (!absl::StartsWith(value, "Unknown error ")) {
68 EXPECT_THAT(absl::base_internal::StrError(i), Eq(expected_strings[i]));
69 }
70 EXPECT_THAT(errno, Eq(ERANGE));
71 }
72 };
73
74 const int kNumThreads = 100;
75 std::vector<std::thread> threads;
76 for (int i = 0; i < kNumThreads; ++i) {
77 threads.push_back(std::thread(thread_fun));
78 }
79 for (auto& thread : threads) {
80 thread.join();
81 }
82
83 EXPECT_THAT(counter, Eq(kNumThreads * kNumCodes));
84 }
85
86 } // namespace
87