diff options
| -rw-r--r-- | src/cam/options.cpp | 217 | ||||
| -rw-r--r-- | src/cam/options.h | 14 |
2 files changed, 199 insertions, 32 deletions
diff --git a/src/cam/options.cpp b/src/cam/options.cpp index 379b68c3..59b26be4 100644 --- a/src/cam/options.cpp +++ b/src/cam/options.cpp @@ -79,6 +79,12 @@ * \var Option::isArray * \brief Whether the option can appear once or multiple times * + * \var Option::parent + * \brief The parent option + * + * \var Option::children + * \brief List of child options, storing all options whose parent is this option + * * \fn Option::hasShortOption() * \brief Tell if the option has a short option specifier (e.g. `-f`) * \return True if the option has a short option specifier, false otherwise @@ -96,6 +102,8 @@ struct Option { const char *help; KeyValueParser *keyValueParser; bool isArray; + Option *parent; + std::list<Option> children; bool hasShortOption() const { return isalnum(opt); } bool hasLongOption() const { return name != nullptr; } @@ -335,7 +343,7 @@ bool KeyValueParser::addOption(const char *name, OptionType type, return false; optionsMap_[name] = Option({ 0, type, name, argument, nullptr, - help, nullptr, false }); + help, nullptr, false, nullptr, {} }); return true; } @@ -472,6 +480,11 @@ void KeyValueParser::usage(int indent) * option. It supports empty values, integers, strings, key-value lists, as well * as arrays of those types. For array values, all array elements shall have the * same type. + * + * OptionValue instances are organized in a tree-based structure that matches + * the parent-child relationship of the options added to the parser. Children + * are retrieved with the children() function, and are stored as an + * OptionsBase<int>. */ /** @@ -662,6 +675,15 @@ std::vector<OptionValue> OptionValue::toArray() const return array_; } +/** + * \brief Retrieve the list of child values + * \return The list of child values + */ +const OptionsParser::Options &OptionValue::children() const +{ + return children_; +} + /* ----------------------------------------------------------------------------- * OptionsParser */ @@ -724,6 +746,32 @@ std::vector<OptionValue> OptionValue::toArray() const * accept an argument, the option value can be access by Options::operator[]() * using the option identifier as the key. The order in which different options * are specified on the command line isn't preserved. + * + * Options can be created with parent-child relationships to organize them as a + * tree instead of a flat list. When parsing a command line, the child options + * are considered related to the parent option that precedes them. This is + * useful when the parent is an array option. The Options values list generated + * by the parser then turns into a tree, which each parent value storing the + * values of child options that follow that instance of the parent option. + * For instance, with a `capture` option specified as a child of a `camera` + * array option, parsing the command line + * + * `--camera 1 --capture=10 --camera 2 --capture=20` + * + * will return an Options instance containing a single OptionValue instance of + * array type, for the `camera` option. The OptionValue will contain two + * entries, with the first entry containing the integer value 1 and the second + * entry the integer value 2. Each of those entries will in turn store an + * Options instance that contains the respective children. The first entry will + * store in its children a `capture` option of value 10, and the second entry a + * `capture` option of value 20. + * + * The command line + * + * `--capture=10 --camera 1` + * + * would result in a parsing error, as the `capture` option has no preceding + * `camera` option on the command line. */ /** @@ -747,13 +795,14 @@ OptionsParser::~OptionsParser() = default; * mandatory argument, or no argument at all * \param[in] argumentName The argument name used in the help text * \param[in] array Whether the option can appear once or multiple times + * \param[in] parent The identifier of the parent option (optional) * * \return True if the option was added successfully, false if an error * occurred. */ bool OptionsParser::addOption(int opt, OptionType type, const char *help, const char *name, OptionArgument argument, - const char *argumentName, bool array) + const char *argumentName, bool array, int parent) { /* * Options must have at least a short or long name, and a text message. @@ -770,9 +819,31 @@ bool OptionsParser::addOption(int opt, OptionType type, const char *help, if (optionsMap_.find(opt) != optionsMap_.end()) return false; - options_.push_back(Option({ opt, type, name, argument, argumentName, - help, nullptr, array })); - optionsMap_[opt] = &options_.back(); + /* + * If a parent is specified, create the option as a child of its parent. + * Otherwise, create it in the parser's options list. + */ + Option *option; + + if (parent) { + auto iter = optionsMap_.find(parent); + if (iter == optionsMap_.end()) + return false; + + Option *parentOpt = iter->second; + parentOpt->children.push_back({ + opt, type, name, argument, argumentName, help, nullptr, + array, parentOpt, {} + }); + option = &parentOpt->children.back(); + } else { + options_.push_back({ opt, type, name, argument, argumentName, + help, nullptr, array, nullptr, {} }); + option = &options_.back(); + } + + optionsMap_[opt] = option; + return true; } @@ -790,13 +861,13 @@ bool OptionsParser::addOption(int opt, OptionType type, const char *help, * occurred. */ bool OptionsParser::addOption(int opt, KeyValueParser *parser, const char *help, - const char *name, bool array) + const char *name, bool array, int parent) { if (!addOption(opt, OptionKeyValue, help, name, ArgumentRequired, - "key=value[,key=value,...]", array)) + "key=value[,key=value,...]", array, parent)) return false; - options_.back().keyValueParser = parser; + optionsMap_[opt]->keyValueParser = parser; return true; } @@ -821,26 +892,26 @@ OptionsParser::Options OptionsParser::parse(int argc, char **argv) * Allocate short and long options arrays large enough to contain all * options. */ - char shortOptions[options_.size() * 3 + 2]; - struct option longOptions[options_.size() + 1]; + char shortOptions[optionsMap_.size() * 3 + 2]; + struct option longOptions[optionsMap_.size() + 1]; unsigned int ids = 0; unsigned int idl = 0; shortOptions[ids++] = ':'; - for (const Option &option : options_) { - if (option.hasShortOption()) { - shortOptions[ids++] = option.opt; - if (option.argument != ArgumentNone) + for (const auto [opt, option] : optionsMap_) { + if (option->hasShortOption()) { + shortOptions[ids++] = opt; + if (option->argument != ArgumentNone) shortOptions[ids++] = ':'; - if (option.argument == ArgumentOptional) + if (option->argument == ArgumentOptional) shortOptions[ids++] = ':'; } - if (option.hasLongOption()) { - longOptions[idl].name = option.name; + if (option->hasLongOption()) { + longOptions[idl].name = option->name; - switch (option.argument) { + switch (option->argument) { case ArgumentNone: longOptions[idl].has_arg = no_argument; break; @@ -853,7 +924,7 @@ OptionsParser::Options OptionsParser::parse(int argc, char **argv) } longOptions[idl].flag = 0; - longOptions[idl].val = option.opt; + longOptions[idl].val = option->opt; idl++; } } @@ -881,10 +952,7 @@ OptionsParser::Options OptionsParser::parse(int argc, char **argv) } const Option &option = *optionsMap_[c]; - if (!options.parseValue(c, option, optarg)) { - std::cerr << "Can't parse " << option.typeName() - << " argument for option " << option.optionName() - << std::endl; + if (!parseValue(option, optarg, &options)) { usage(); return options; } @@ -906,15 +974,16 @@ void OptionsParser::usage() { unsigned int indent = 0; - for (const Option &option : options_) { + for (const auto &opt : optionsMap_) { + const Option *option = opt.second; unsigned int length = 14; - if (option.hasLongOption()) - length += 2 + strlen(option.name); - if (option.argument != ArgumentNone) - length += 1 + strlen(option.argumentName); - if (option.argument == ArgumentOptional) + if (option->hasLongOption()) + length += 2 + strlen(option->name); + if (option->argument != ArgumentNone) + length += 1 + strlen(option->argumentName); + if (option->argument == ArgumentOptional) length += 2; - if (option.isArray) + if (option->isArray) length += 4; if (length > indent) @@ -937,6 +1006,8 @@ void OptionsParser::usage() void OptionsParser::usageOptions(const std::list<Option> &options, unsigned int indent) { + std::vector<const Option *> parentOptions; + for (const Option &option : options) { std::string argument; if (option.hasShortOption()) @@ -981,5 +1052,91 @@ void OptionsParser::usageOptions(const std::list<Option> &options, if (option.keyValueParser) option.keyValueParser->usage(indent); + + if (!option.children.empty()) + parentOptions.push_back(&option); + } + + if (parentOptions.empty()) + return; + + for (const Option *option : parentOptions) { + std::cerr << std::endl << "Options valid in the context of " + << option->optionName() << ":" << std::endl; + usageOptions(option->children, indent); + } +} + +std::tuple<OptionsParser::Options *, const Option *> +OptionsParser::childOption(const Option *parent, Options *options) +{ + /* + * The parent argument points to the parent of the leaf node Option, + * and the options argument to the root node of the Options tree. Use + * recursive calls to traverse the Option tree up to the root node while + * traversing the Options tree down to the leaf node: + */ + + /* + * - If we have no parent, we've reached the root node of the Option + * tree, the options argument is what we need. + */ + if (!parent) + return { options, nullptr }; + + /* + * - If the parent has a parent, use recursion to move one level up the + * Option tree. This returns the Options corresponding to parent, or + * nullptr if a suitable Options child isn't found. + */ + if (parent->parent) { + const Option *error; + std::tie(options, error) = childOption(parent->parent, options); + + /* Propagate the error all the way back up the call stack. */ + if (!error) + return { options, error }; + } + + /* + * - The parent has no parent, we're now one level down the root. + * Return the Options child corresponding to the parent. The child may + * not exist if options are specified in an incorrect order. + */ + if (!options->isSet(parent->opt)) + return { nullptr, parent }; + + /* + * If the child value is of array type, children are not stored in the + * value .children() list, but in the .children() of the value's array + * elements. Use the last array element in that case, as a child option + * relates to the last instance of its parent option. + */ + const OptionValue *value = &(*options)[parent->opt]; + if (value->type() == OptionValue::ValueArray) + value = &value->toArray().back(); + + return { const_cast<Options *>(&value->children()), nullptr }; +} + +bool OptionsParser::parseValue(const Option &option, const char *arg, + Options *options) +{ + const Option *error; + + std::tie(options, error) = childOption(option.parent, options); + if (error) { + std::cerr << "Option " << option.optionName() << " requires a " + << error->optionName() << " context" << std::endl; + return false; + } + + if (!options->parseValue(option.opt, option, arg)) { + std::cerr << "Can't parse " << option.typeName() + << " argument for option " << option.optionName() + << std::endl; + return false; } + + return true; } diff --git a/src/cam/options.h b/src/cam/options.h index 5c51a94c..e894822c 100644 --- a/src/cam/options.h +++ b/src/cam/options.h @@ -10,6 +10,7 @@ #include <ctype.h> #include <list> #include <map> +#include <tuple> #include <vector> class KeyValueParser; @@ -91,9 +92,11 @@ public: bool addOption(int opt, OptionType type, const char *help, const char *name = nullptr, OptionArgument argument = ArgumentNone, - const char *argumentName = nullptr, bool array = false); + const char *argumentName = nullptr, bool array = false, + int parent = 0); bool addOption(int opt, KeyValueParser *parser, const char *help, - const char *name = nullptr, bool array = false); + const char *name = nullptr, bool array = false, + int parent = 0); Options parse(int argc, char *argv[]); void usage(); @@ -104,6 +107,10 @@ private: void usageOptions(const std::list<Option> &options, unsigned int indent); + std::tuple<OptionsParser::Options *, const Option *> + childOption(const Option *parent, Options *options); + bool parseValue(const Option &option, const char *arg, Options *options); + std::list<Option> options_; std::map<unsigned int, Option *> optionsMap_; }; @@ -139,12 +146,15 @@ public: KeyValueParser::Options toKeyValues() const; std::vector<OptionValue> toArray() const; + const OptionsParser::Options &children() const; + private: ValueType type_; int integer_; std::string string_; KeyValueParser::Options keyValues_; std::vector<OptionValue> array_; + OptionsParser::Options children_; }; #endif /* __CAM_OPTIONS_H__ */ |