diff options
Diffstat (limited to 'absl/flags/internal/usage.cc')
| -rw-r--r-- | absl/flags/internal/usage.cc | 273 |
1 files changed, 200 insertions, 73 deletions
diff --git a/absl/flags/internal/usage.cc b/absl/flags/internal/usage.cc index 0805df31..a588c7f7 100644 --- a/absl/flags/internal/usage.cc +++ b/absl/flags/internal/usage.cc @@ -37,26 +37,26 @@ #include "absl/strings/str_split.h" #include "absl/strings/string_view.h" -ABSL_FLAG(bool, help, false, - "show help on important flags for this binary [tip: all flags can " - "have two dashes]"); -ABSL_FLAG(bool, helpfull, false, "show help on all flags"); -ABSL_FLAG(bool, helpshort, false, - "show help on only the main module for this program"); -ABSL_FLAG(bool, helppackage, false, - "show help on all modules in the main package"); -ABSL_FLAG(bool, version, false, "show version and build info and exit"); -ABSL_FLAG(bool, only_check_args, false, "exit after checking all flags"); -ABSL_FLAG(std::string, helpon, "", - "show help on the modules named by this flag value"); -ABSL_FLAG(std::string, helpmatch, "", - "show help on modules whose name contains the specified substr"); +// Dummy global variables to prevent anyone else defining these. +bool FLAGS_help = false; +bool FLAGS_helpfull = false; +bool FLAGS_helpshort = false; +bool FLAGS_helppackage = false; +bool FLAGS_version = false; +bool FLAGS_only_check_args = false; +bool FLAGS_helpon = false; +bool FLAGS_helpmatch = false; namespace absl { ABSL_NAMESPACE_BEGIN namespace flags_internal { namespace { +using PerFlagFilter = std::function<bool(const absl::CommandLineFlag&)>; + +// Maximum length size in a human readable format. +constexpr size_t kHrfMaxLineLength = 80; + // This class is used to emit an XML element with `tag` and `text`. // It adds opening and closing tags and escapes special characters in the text. // For example: @@ -109,9 +109,12 @@ class FlagHelpPrettyPrinter { public: // Pretty printer holds on to the std::ostream& reference to direct an output // to that stream. - FlagHelpPrettyPrinter(int max_line_len, std::ostream& out) + FlagHelpPrettyPrinter(size_t max_line_len, size_t min_line_len, + size_t wrapped_line_indent, std::ostream& out) : out_(out), max_line_len_(max_line_len), + min_line_len_(min_line_len), + wrapped_line_indent_(wrapped_line_indent), line_len_(0), first_line_(true) {} @@ -145,7 +148,8 @@ class FlagHelpPrettyPrinter { } // Write the token, ending the string first if necessary/possible. - if (!new_line && (line_len_ + token.size() >= max_line_len_)) { + if (!new_line && + (line_len_ + static_cast<int>(token.size()) >= max_line_len_)) { EndLine(); new_line = true; } @@ -164,13 +168,12 @@ class FlagHelpPrettyPrinter { void StartLine() { if (first_line_) { - out_ << " "; - line_len_ = 4; + line_len_ = min_line_len_; first_line_ = false; } else { - out_ << " "; - line_len_ = 6; + line_len_ = min_line_len_ + wrapped_line_indent_; } + out_ << std::string(line_len_, ' '); } void EndLine() { out_ << '\n'; @@ -179,13 +182,15 @@ class FlagHelpPrettyPrinter { private: std::ostream& out_; - const int max_line_len_; - int line_len_; + const size_t max_line_len_; + const size_t min_line_len_; + const size_t wrapped_line_indent_; + size_t line_len_; bool first_line_; }; void FlagHelpHumanReadable(const CommandLineFlag& flag, std::ostream& out) { - FlagHelpPrettyPrinter printer(80, out); // Max line length is 80. + FlagHelpPrettyPrinter printer(kHrfMaxLineLength, 4, 2, out); // Flag name. printer.Write(absl::StrCat("--", flag.Name())); @@ -221,7 +226,7 @@ void FlagHelpHumanReadable(const CommandLineFlag& flag, std::ostream& out) { // If a flag's help message has been stripped (e.g. by adding '#define // STRIP_FLAG_HELP 1' then this flag will not be displayed by '--help' // and its variants. -void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb, +void FlagsHelpImpl(std::ostream& out, PerFlagFilter filter_cb, HelpFormat format, absl::string_view program_usage_message) { if (format == HelpFormat::kHumanReadable) { out << flags_internal::ShortProgramInvocationName() << ": " @@ -256,10 +261,10 @@ void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb, // If the flag has been stripped, pretend that it doesn't exist. if (flag.Help() == flags_internal::kStrippedFlagHelp) return; - std::string flag_filename = flag.Filename(); - // Make sure flag satisfies the filter - if (!filter_cb || !filter_cb(flag_filename)) return; + if (!filter_cb(flag)) return; + + std::string flag_filename = flag.Filename(); matching_flags[std::string(flags_internal::Package(flag_filename))] [flag_filename] @@ -289,15 +294,34 @@ void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb, } if (format == HelpFormat::kHumanReadable) { + FlagHelpPrettyPrinter printer(kHrfMaxLineLength, 0, 0, out); + if (filter_cb && matching_flags.empty()) { - out << " No modules matched: use -helpfull\n"; + printer.Write("No flags matched.\n", true); } + printer.EndLine(); + printer.Write( + "Try --helpfull to get a list of all flags or --help=substring " + "shows help for flags which include specified substring in either " + "in the name, or description or path.\n", + true); } else { // The end of the document. out << "</AllFlags>\n"; } } +void FlagsHelpImpl(std::ostream& out, + flags_internal::FlagKindFilter filename_filter_cb, + HelpFormat format, absl::string_view program_usage_message) { + FlagsHelpImpl( + out, + [&](const absl::CommandLineFlag& flag) { + return filename_filter_cb && filename_filter_cb(flag.Filename()); + }, + format, program_usage_message); +} + } // namespace // -------------------------------------------------------------------- @@ -309,7 +333,7 @@ void FlagHelp(std::ostream& out, const CommandLineFlag& flag, } // -------------------------------------------------------------------- -// Produces the help messages for all flags matching the filter. +// Produces the help messages for all flags matching the filename filter. // If filter is empty produces help messages for all flags. void FlagsHelp(std::ostream& out, absl::string_view filter, HelpFormat format, absl::string_view program_usage_message) { @@ -324,66 +348,169 @@ void FlagsHelp(std::ostream& out, absl::string_view filter, HelpFormat format, // If so, handles them appropriately. int HandleUsageFlags(std::ostream& out, absl::string_view program_usage_message) { - if (absl::GetFlag(FLAGS_helpshort)) { - flags_internal::FlagsHelpImpl( - out, flags_internal::GetUsageConfig().contains_helpshort_flags, - HelpFormat::kHumanReadable, program_usage_message); - return 1; - } + switch (GetFlagsHelpMode()) { + case HelpMode::kNone: + break; + case HelpMode::kImportant: + flags_internal::FlagsHelpImpl( + out, flags_internal::GetUsageConfig().contains_help_flags, + GetFlagsHelpFormat(), program_usage_message); + return 1; + + case HelpMode::kShort: + flags_internal::FlagsHelpImpl( + out, flags_internal::GetUsageConfig().contains_helpshort_flags, + GetFlagsHelpFormat(), program_usage_message); + return 1; + + case HelpMode::kFull: + flags_internal::FlagsHelp(out, "", GetFlagsHelpFormat(), + program_usage_message); + return 1; + + case HelpMode::kPackage: + flags_internal::FlagsHelpImpl( + out, flags_internal::GetUsageConfig().contains_helppackage_flags, + GetFlagsHelpFormat(), program_usage_message); + + return 1; + + case HelpMode::kMatch: { + std::string substr = GetFlagsHelpMatchSubstr(); + if (substr.empty()) { + // show all options + flags_internal::FlagsHelp(out, substr, GetFlagsHelpFormat(), + program_usage_message); + } else { + auto filter_cb = [&substr](const absl::CommandLineFlag& flag) { + if (absl::StrContains(flag.Name(), substr)) return true; + if (absl::StrContains(flag.Filename(), substr)) return true; + if (absl::StrContains(flag.Help(), substr)) return true; + + return false; + }; + flags_internal::FlagsHelpImpl( + out, filter_cb, HelpFormat::kHumanReadable, program_usage_message); + } - if (absl::GetFlag(FLAGS_helpfull)) { - // show all options - flags_internal::FlagsHelp(out, "", HelpFormat::kHumanReadable, - program_usage_message); - return 1; + return 1; + } + case HelpMode::kVersion: + if (flags_internal::GetUsageConfig().version_string) + out << flags_internal::GetUsageConfig().version_string(); + // Unlike help, we may be asking for version in a script, so return 0 + return 0; + + case HelpMode::kOnlyCheckArgs: + return 0; } - if (!absl::GetFlag(FLAGS_helpon).empty()) { - flags_internal::FlagsHelp( - out, absl::StrCat("/", absl::GetFlag(FLAGS_helpon), "."), - HelpFormat::kHumanReadable, program_usage_message); - return 1; - } + return -1; +} - if (!absl::GetFlag(FLAGS_helpmatch).empty()) { - flags_internal::FlagsHelp(out, absl::GetFlag(FLAGS_helpmatch), - HelpFormat::kHumanReadable, - program_usage_message); - return 1; - } +// -------------------------------------------------------------------- +// Globals representing usage reporting flags - if (absl::GetFlag(FLAGS_help)) { - flags_internal::FlagsHelpImpl( - out, flags_internal::GetUsageConfig().contains_help_flags, - HelpFormat::kHumanReadable, program_usage_message); +namespace { - out << "\nTry --helpfull to get a list of all flags.\n"; +ABSL_CONST_INIT absl::Mutex help_attributes_guard(absl::kConstInit); +ABSL_CONST_INIT std::string* match_substr + ABSL_GUARDED_BY(help_attributes_guard) = nullptr; +ABSL_CONST_INIT HelpMode help_mode ABSL_GUARDED_BY(help_attributes_guard) = + HelpMode::kNone; +ABSL_CONST_INIT HelpFormat help_format ABSL_GUARDED_BY(help_attributes_guard) = + HelpFormat::kHumanReadable; - return 1; - } +} // namespace - if (absl::GetFlag(FLAGS_helppackage)) { - flags_internal::FlagsHelpImpl( - out, flags_internal::GetUsageConfig().contains_helppackage_flags, - HelpFormat::kHumanReadable, program_usage_message); +std::string GetFlagsHelpMatchSubstr() { + absl::MutexLock l(&help_attributes_guard); + if (match_substr == nullptr) return ""; + return *match_substr; +} - out << "\nTry --helpfull to get a list of all flags.\n"; +void SetFlagsHelpMatchSubstr(absl::string_view substr) { + absl::MutexLock l(&help_attributes_guard); + if (match_substr == nullptr) match_substr = new std::string; + match_substr->assign(substr.data(), substr.size()); +} - return 1; +HelpMode GetFlagsHelpMode() { + absl::MutexLock l(&help_attributes_guard); + return help_mode; +} + +void SetFlagsHelpMode(HelpMode mode) { + absl::MutexLock l(&help_attributes_guard); + help_mode = mode; +} + +HelpFormat GetFlagsHelpFormat() { + absl::MutexLock l(&help_attributes_guard); + return help_format; +} + +void SetFlagsHelpFormat(HelpFormat format) { + absl::MutexLock l(&help_attributes_guard); + help_format = format; +} + +// Deduces usage flags from the input argument in a form --name=value or +// --name. argument is already split into name and value before we call this +// function. +bool DeduceUsageFlags(absl::string_view name, absl::string_view value) { + if (absl::ConsumePrefix(&name, "help")) { + if (name == "") { + if (value.empty()) { + SetFlagsHelpMode(HelpMode::kImportant); + } else { + SetFlagsHelpMode(HelpMode::kMatch); + SetFlagsHelpMatchSubstr(value); + } + return true; + } + + if (name == "match") { + SetFlagsHelpMode(HelpMode::kMatch); + SetFlagsHelpMatchSubstr(value); + return true; + } + + if (name == "on") { + SetFlagsHelpMode(HelpMode::kMatch); + SetFlagsHelpMatchSubstr(absl::StrCat("/", value, ".")); + return true; + } + + if (name == "full") { + SetFlagsHelpMode(HelpMode::kFull); + return true; + } + + if (name == "short") { + SetFlagsHelpMode(HelpMode::kShort); + return true; + } + + if (name == "package") { + SetFlagsHelpMode(HelpMode::kPackage); + return true; + } + + return false; } - if (absl::GetFlag(FLAGS_version)) { - if (flags_internal::GetUsageConfig().version_string) - out << flags_internal::GetUsageConfig().version_string(); - // Unlike help, we may be asking for version in a script, so return 0 - return 0; + if (name == "version") { + SetFlagsHelpMode(HelpMode::kVersion); + return true; } - if (absl::GetFlag(FLAGS_only_check_args)) { - return 0; + if (name == "only_check_args") { + SetFlagsHelpMode(HelpMode::kOnlyCheckArgs); + return true; } - return -1; + return false; } } // namespace flags_internal |