diff options
author | Abseil Team <absl-team@google.com> | 2019-03-08T22·06-0800 |
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committer | Derek Mauro <dmauro@google.com> | 2019-03-08T22·11-0500 |
commit | 88a152ae747c3c42dc9167d46c590929b048d436 (patch) | |
tree | e0858f1abd59c78a59b7d8449b7fb7c76904c88c /absl/base/internal/scoped_set_env.cc | |
parent | c1cecb25a94c075725e9d2640f6b978a8f61957b (diff) |
Export of internal Abseil changes.
-- 5dc8d7504b7c11710b19365a6582c288c8992366 by Derek Mauro <dmauro@google.com>: Fix constexpr Span::last under MSVC and add Span constexpr tests. PiperOrigin-RevId: 237515952 -- 5ea8c146e653bbc49ff7e698699478242df7de35 by Derek Mauro <dmauro@google.com>: Implement Span::first and Span::last from C++20. https://github.com/abseil/abseil-cpp/pull/274 PiperOrigin-RevId: 237494399 -- 08db3417f1d8fe4556255d57a2f0df51b09bdd9a by Derek Mauro <dmauro@google.com>: HTTPS in more URLs. PiperOrigin-RevId: 237486823 -- 83ec63a7f8e47b62af619546f9f7b3bf72e74e86 by Derek Mauro <dmauro@google.com>: Changed HTTP URLs to HTTPS where possible. https://github.com/abseil/abseil-cpp/pull/270 PiperOrigin-RevId: 237445310 -- 220bf279c14cb31efa239500d1a70e0ac0c32e3c by Abseil Team <absl-team@google.com>: Support parsing decltype(nullptr) as a type. PiperOrigin-RevId: 237336739 -- ced234bbe78f5d495c3f6f6a9c2e0a95f7c080a5 by Gennadiy Rozental <rogeeff@google.com>: Introduce internal interface for setting environment variable value in scope PiperOrigin-RevId: 237275806 -- 1f1acb4e294af24d9f7598e85163d5e1d9958ae9 by Samuel Benzaquen <sbenza@google.com>: Avoid using aliases in the SFINAE expressions to make it more compatible with MSVC. Turn on the tests in MSVC. PiperOrigin-RevId: 237261456 -- 06cf7de6250a0572ef90fa1176f742ca0451ce71 by Derek Mauro <dmauro@google.com>: Fix unused variable warning. PiperOrigin-RevId: 237108006 GitOrigin-RevId: 5dc8d7504b7c11710b19365a6582c288c8992366 Change-Id: Ife5182c80942945c4e8700844c8febb482d6ad82
Diffstat (limited to 'absl/base/internal/scoped_set_env.cc')
-rw-r--r-- | absl/base/internal/scoped_set_env.cc | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/absl/base/internal/scoped_set_env.cc b/absl/base/internal/scoped_set_env.cc new file mode 100644 index 000000000000..9b1641240cf8 --- /dev/null +++ b/absl/base/internal/scoped_set_env.cc @@ -0,0 +1,79 @@ +// Copyright 2019 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/scoped_set_env.h" + +#ifdef _WIN32 +#include <windows.h> +#endif + +#include <cstdlib> + +#include "absl/base/internal/raw_logging.h" + +namespace absl { +namespace base_internal { + +namespace { + +#ifdef _WIN32 +const int kMaxEnvVarValueSize = 1024; +#endif + +void SetEnvVar(const char* name, const char* value) { +#ifdef _WIN32 + SetEnvironmentVariable(name, value); +#else + if (value == nullptr) { + ::unsetenv(name); + } else { + ::setenv(name, value, 1); + } +#endif +} + +} // namespace + +ScopedSetEnv::ScopedSetEnv(const char* var_name, const char* new_value) + : var_name_(var_name), was_unset_(false) { +#ifdef _WIN32 + char buf[kMaxEnvVarValueSize]; + auto get_res = GetEnvironmentVariable(var_name_.c_str(), buf, sizeof(buf)); + ABSL_INTERNAL_CHECK(get_res < sizeof(buf), "value exceeds buffer size"); + + if (get_res == 0) { + was_unset_ = (GetLastError() == ERROR_ENVVAR_NOT_FOUND); + } else { + old_value_.assign(buf, get_res); + } + + SetEnvironmentVariable(var_name_.c_str(), new_value); +#else + const char* val = ::getenv(var_name_.c_str()); + if (val == nullptr) { + was_unset_ = true; + } else { + old_value_ = val; + } +#endif + + SetEnvVar(var_name_.c_str(), new_value); +} + +ScopedSetEnv::~ScopedSetEnv() { + SetEnvVar(var_name_.c_str(), was_unset_ ? nullptr : old_value_.c_str()); +} + +} // namespace base_internal +} // namespace absl |