diff options
Diffstat (limited to 'third_party/abseil_cpp/absl/base/internal/strerror.cc')
-rw-r--r-- | third_party/abseil_cpp/absl/base/internal/strerror.cc | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/third_party/abseil_cpp/absl/base/internal/strerror.cc b/third_party/abseil_cpp/absl/base/internal/strerror.cc new file mode 100644 index 000000000000..af181513cde9 --- /dev/null +++ b/third_party/abseil_cpp/absl/base/internal/strerror.cc @@ -0,0 +1,75 @@ +// Copyright 2020 The Abseil Authors. +// +// 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 +// +// https://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 "absl/base/internal/strerror.h" + +#include <cerrno> +#include <cstddef> +#include <cstdio> +#include <cstring> +#include <string> +#include <type_traits> + +#include "absl/base/attributes.h" +#include "absl/base/internal/errno_saver.h" + +namespace absl { +ABSL_NAMESPACE_BEGIN +namespace base_internal { +namespace { +const char* StrErrorAdaptor(int errnum, char* buf, size_t buflen) { +#if defined(_WIN32) + int rc = strerror_s(buf, buflen, errnum); + buf[buflen - 1] = '\0'; // guarantee NUL termination + if (rc == 0 && strncmp(buf, "Unknown error", buflen) == 0) *buf = '\0'; + return buf; +#else +#if defined(__GLIBC__) || defined(__APPLE__) + // Use the BSD sys_errlist API provided by GNU glibc and others to + // avoid any need to copy the message into the local buffer first. + if (0 <= errnum && errnum < sys_nerr) { + if (const char* p = sys_errlist[errnum]) { + return p; + } + } +#endif + // The type of `ret` is platform-specific; both of these branches must compile + // either way but only one will execute on any given platform: + auto ret = strerror_r(errnum, buf, buflen); + if (std::is_same<decltype(ret), int>::value) { + // XSI `strerror_r`; `ret` is `int`: + if (ret) *buf = '\0'; + return buf; + } else { + // GNU `strerror_r`; `ret` is `char *`: + return reinterpret_cast<const char*>(ret); + } +#endif +} +} // namespace + +std::string StrError(int errnum) { + absl::base_internal::ErrnoSaver errno_saver; + char buf[100]; + const char* str = StrErrorAdaptor(errnum, buf, sizeof buf); + if (*str == '\0') { + snprintf(buf, sizeof buf, "Unknown error %d", errnum); + str = buf; + } + return str; +} + +} // namespace base_internal +ABSL_NAMESPACE_END +} // namespace absl |