// // 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/flags/usage_config.h" #include <iostream> #include <string> #include "absl/base/attributes.h" #include "absl/base/config.h" #include "absl/base/const_init.h" #include "absl/base/thread_annotations.h" #include "absl/flags/internal/path_util.h" #include "absl/flags/internal/program_name.h" #include "absl/strings/match.h" #include "absl/strings/string_view.h" #include "absl/strings/strip.h" #include "absl/synchronization/mutex.h" extern "C" { // Additional report of fatal usage error message before we std::exit. Error is // fatal if is_fatal argument to ReportUsageError is true. ABSL_ATTRIBUTE_WEAK void AbslInternalReportFatalUsageError(absl::string_view) {} } // extern "C" namespace absl { ABSL_NAMESPACE_BEGIN namespace flags_internal { namespace { // -------------------------------------------------------------------- // Returns true if flags defined in the filename should be reported with // -helpshort flag. bool ContainsHelpshortFlags(absl::string_view filename) { // By default we only want flags in binary's main. We expect the main // routine to reside in <program>.cc or <program>-main.cc or // <program>_main.cc, where the <program> is the name of the binary // (without .exe on Windows). auto suffix = flags_internal::Basename(filename); auto program_name = flags_internal::ShortProgramInvocationName(); absl::string_view program_name_ref = program_name; #if defined(_WIN32) absl::ConsumeSuffix(&program_name_ref, ".exe"); #endif if (!absl::ConsumePrefix(&suffix, program_name_ref)) return false; return absl::StartsWith(suffix, ".") || absl::StartsWith(suffix, "-main.") || absl::StartsWith(suffix, "_main."); } // -------------------------------------------------------------------- // Returns true if flags defined in the filename should be reported with // -helppackage flag. bool ContainsHelppackageFlags(absl::string_view filename) { // TODO(rogeeff): implement properly when registry is available. return ContainsHelpshortFlags(filename); } // -------------------------------------------------------------------- // Generates program version information into supplied output. std::string VersionString() { std::string version_str(flags_internal::ShortProgramInvocationName()); version_str += "\n"; #if !defined(NDEBUG) version_str += "Debug build (NDEBUG not #defined)\n"; #endif return version_str; } // -------------------------------------------------------------------- // Normalizes the filename specific to the build system/filesystem used. std::string NormalizeFilename(absl::string_view filename) { // Skip any leading slashes auto pos = filename.find_first_not_of("\\/"); if (pos == absl::string_view::npos) return ""; filename.remove_prefix(pos); return std::string(filename); } // -------------------------------------------------------------------- ABSL_CONST_INIT absl::Mutex custom_usage_config_guard(absl::kConstInit); ABSL_CONST_INIT FlagsUsageConfig* custom_usage_config ABSL_GUARDED_BY(custom_usage_config_guard) = nullptr; } // namespace FlagsUsageConfig GetUsageConfig() { absl::MutexLock l(&custom_usage_config_guard); if (custom_usage_config) return *custom_usage_config; FlagsUsageConfig default_config; default_config.contains_helpshort_flags = &ContainsHelpshortFlags; default_config.contains_help_flags = &ContainsHelppackageFlags; default_config.contains_helppackage_flags = &ContainsHelppackageFlags; default_config.version_string = &VersionString; default_config.normalize_filename = &NormalizeFilename; return default_config; } void ReportUsageError(absl::string_view msg, bool is_fatal) { std::cerr << "ERROR: " << msg << std::endl; if (is_fatal) { AbslInternalReportFatalUsageError(msg); } } } // namespace flags_internal void SetFlagsUsageConfig(FlagsUsageConfig usage_config) { absl::MutexLock l(&flags_internal::custom_usage_config_guard); if (!usage_config.contains_helpshort_flags) usage_config.contains_helpshort_flags = flags_internal::ContainsHelpshortFlags; if (!usage_config.contains_help_flags) usage_config.contains_help_flags = flags_internal::ContainsHelppackageFlags; if (!usage_config.contains_helppackage_flags) usage_config.contains_helppackage_flags = flags_internal::ContainsHelppackageFlags; if (!usage_config.version_string) usage_config.version_string = flags_internal::VersionString; if (!usage_config.normalize_filename) usage_config.normalize_filename = flags_internal::NormalizeFilename; if (flags_internal::custom_usage_config) *flags_internal::custom_usage_config = usage_config; else flags_internal::custom_usage_config = new FlagsUsageConfig(usage_config); } ABSL_NAMESPACE_END } // namespace absl