//===- OptTable.h - Option Table --------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_OPTION_OPTTABLE_H
#define LLVM_OPTION_OPTTABLE_H
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Option/OptSpecifier.h"
#include "llvm/Support/StringSaver.h"
#include <cassert>
#include <string>
#include <vector>
namespace llvm {
class raw_ostream;
template <typename Fn> class function_ref;
namespace opt {
class Arg;
class ArgList;
class InputArgList;
class Option;
/// Provide access to the Option info table.
///
/// The OptTable class provides a layer of indirection which allows Option
/// instance to be created lazily. In the common case, only a few options will
/// be needed at runtime; the OptTable class maintains enough information to
/// parse command lines without instantiating Options, while letting other
/// parts of the driver still use Option instances where convenient.
class OptTable {
public:
/// Entry for a single option instance in the option data table.
struct Info {
/// A null terminated array of prefix strings to apply to name while
/// matching.
ArrayRef<StringLiteral> Prefixes;
StringRef Name;
const char *HelpText;
const char *MetaVar;
unsigned ID;
unsigned char Kind;
unsigned char Param;
unsigned int Flags;
unsigned short GroupID;
unsigned short AliasID;
const char *AliasArgs;
const char *Values;
};
private:
/// The option information table.
ArrayRef<Info> OptionInfos;
bool IgnoreCase;
bool GroupedShortOptions = false;
const char *EnvVar = nullptr;
unsigned InputOptionID = 0;
unsigned UnknownOptionID = 0;
protected:
/// The index of the first option which can be parsed (i.e., is not a
/// special option like 'input' or 'unknown', and is not an option group).
unsigned FirstSearchableIndex = 0;
/// The union of the first element of all option prefixes.
SmallString<8> PrefixChars;
/// The union of all option prefixes. If an argument does not begin with
/// one of these, it is an input.
virtual ArrayRef<StringLiteral> getPrefixesUnion() const = 0;
private:
const Info &getInfo(OptSpecifier Opt) const {
unsigned id = Opt.getID();
assert(id > 0 && id - 1 < getNumOptions() && "Invalid Option ID.");
return OptionInfos[id - 1];
}
std::unique_ptr<Arg> parseOneArgGrouped(InputArgList &Args,
unsigned &Index) const;
protected:
/// Initialize OptTable using Tablegen'ed OptionInfos. Child class must
/// manually call \c buildPrefixChars once they are fully constructed.
OptTable(ArrayRef<Info> OptionInfos, bool IgnoreCase = false);
/// Build (or rebuild) the PrefixChars member.
void buildPrefixChars();
public:
virtual ~OptTable();
/// Return the total number of option classes.
unsigned getNumOptions() const { return OptionInfos.size(); }
/// Get the given Opt's Option instance, lazily creating it
/// if necessary.
///
/// \return The option, or null for the INVALID option id.
const Option getOption(OptSpecifier Opt) const;
/// Lookup the name of the given option.
StringRef getOptionName(OptSpecifier id) const { return getInfo(id).Name; }
/// Get the kind of the given option.
unsigned getOptionKind(OptSpecifier id) const {
return getInfo(id).Kind;
}
/// Get the group id for the given option.
unsigned getOptionGroupID(OptSpecifier id) const {
return getInfo(id).GroupID;
}
/// Get the help text to use to describe this option.
const char *getOptionHelpText(OptSpecifier id) const {
return getInfo(id).HelpText;
}
/// Get the meta-variable name to use when describing
/// this options values in the help text.
const char *getOptionMetaVar(OptSpecifier id) const {
return getInfo(id).MetaVar;
}
/// Specify the environment variable where initial options should be read.
void setInitialOptionsFromEnvironment(const char *E) { EnvVar = E; }
/// Support grouped short options. e.g. -ab represents -a -b.
void setGroupedShortOptions(bool Value) { GroupedShortOptions = Value; }
/// Find possible value for given flags. This is used for shell
/// autocompletion.
///
/// \param [in] Option - Key flag like "-stdlib=" when "-stdlib=l"
/// was passed to clang.
///
/// \param [in] Arg - Value which we want to autocomplete like "l"
/// when "-stdlib=l" was passed to clang.
///
/// \return The vector of possible values.
std::vector<std::string> suggestValueCompletions(StringRef Option,
StringRef Arg) const;
/// Find flags from OptTable which starts with Cur.
///
/// \param [in] Cur - String prefix that all returned flags need
// to start with.
///
/// \return The vector of flags which start with Cur.
std::vector<std::string> findByPrefix(StringRef Cur,
unsigned int DisableFlags) const;
/// Find the OptTable option that most closely matches the given string.
///
/// \param [in] Option - A string, such as "-stdlibs=l", that represents user
/// input of an option that may not exist in the OptTable. Note that the
/// string includes prefix dashes "-" as well as values "=l".
/// \param [out] NearestString - The nearest option string found in the
/// OptTable.
/// \param [in] FlagsToInclude - Only find options with any of these flags.
/// Zero is the default, which includes all flags.
/// \param [in] FlagsToExclude - Don't find options with this flag. Zero
/// is the default, and means exclude nothing.
/// \param [in] MinimumLength - Don't find options shorter than this length.
/// For example, a minimum length of 3 prevents "-x" from being considered
/// near to "-S".
/// \param [in] MaximumDistance - Don't find options whose distance is greater
/// than this value.
///
/// \return The edit distance of the nearest string found.
unsigned findNearest(StringRef Option, std::string &NearestString,
unsigned FlagsToInclude = 0, unsigned FlagsToExclude = 0,
unsigned MinimumLength = 4,
unsigned MaximumDistance = UINT_MAX) const;
bool findExact(StringRef Option, std::string &ExactString,
unsigned FlagsToInclude = 0,
unsigned FlagsToExclude = 0) const {
return findNearest(Option, ExactString, FlagsToInclude, FlagsToExclude, 4,
0) == 0;
}
/// Parse a single argument; returning the new argument and
/// updating Index.
///
/// \param [in,out] Index - The current parsing position in the argument
/// string list; on return this will be the index of the next argument
/// string to parse.
/// \param [in] FlagsToInclude - Only parse options with any of these flags.
/// Zero is the default which includes all flags.
/// \param [in] FlagsToExclude - Don't parse options with this flag. Zero
/// is the default and means exclude nothing.
///
/// \return The parsed argument, or 0 if the argument is missing values
/// (in which case Index still points at the conceptual next argument string
/// to parse).
std::unique_ptr<Arg> ParseOneArg(const ArgList &Args, unsigned &Index,
unsigned FlagsToInclude = 0,
unsigned FlagsToExclude = 0) const;
/// Parse an list of arguments into an InputArgList.
///
/// The resulting InputArgList will reference the strings in [\p ArgBegin,
/// \p ArgEnd), and their lifetime should extend past that of the returned
/// InputArgList.
///
/// The only error that can occur in this routine is if an argument is
/// missing values; in this case \p MissingArgCount will be non-zero.
///
/// \param MissingArgIndex - On error, the index of the option which could
/// not be parsed.
/// \param MissingArgCount - On error, the number of missing options.
/// \param FlagsToInclude - Only parse options with any of these flags.
/// Zero is the default which includes all flags.
/// \param FlagsToExclude - Don't parse options with this flag. Zero
/// is the default and means exclude nothing.
/// \return An InputArgList; on error this will contain all the options
/// which could be parsed.
InputArgList ParseArgs(ArrayRef<const char *> Args, unsigned &MissingArgIndex,
unsigned &MissingArgCount, unsigned FlagsToInclude = 0,
unsigned FlagsToExclude = 0) const;
/// A convenience helper which handles optional initial options populated from
/// an environment variable, expands response files recursively and parses
/// options.
///
/// \param ErrorFn - Called on a formatted error message for missing arguments
/// or unknown options.
/// \return An InputArgList; on error this will contain all the options which
/// could be parsed.
InputArgList parseArgs(int Argc, char *const *Argv, OptSpecifier Unknown,
StringSaver &Saver,
function_ref<void(StringRef)> ErrorFn) const;
/// Render the help text for an option table.
///
/// \param OS - The stream to write the help text to.
/// \param Usage - USAGE: Usage
/// \param Title - OVERVIEW: Title
/// \param FlagsToInclude - If non-zero, only include options with any
/// of these flags set.
/// \param FlagsToExclude - Exclude options with any of these flags set.
/// \param ShowAllAliases - If true, display all options including aliases
/// that don't have help texts. By default, we display
/// only options that are not hidden and have help
/// texts.
void printHelp(raw_ostream &OS, const char *Usage, const char *Title,
unsigned FlagsToInclude, unsigned FlagsToExclude,
bool ShowAllAliases) const;
void printHelp(raw_ostream &OS, const char *Usage, const char *Title,
bool ShowHidden = false, bool ShowAllAliases = false) const;
};
/// Specialization of OptTable
class GenericOptTable : public OptTable {
SmallVector<StringLiteral> PrefixesUnionBuffer;
protected:
GenericOptTable(ArrayRef<Info> OptionInfos, bool IgnoreCase = false);
ArrayRef<StringLiteral> getPrefixesUnion() const final {
return PrefixesUnionBuffer;
}
};
class PrecomputedOptTable : public OptTable {
ArrayRef<StringLiteral> PrefixesUnion;
protected:
PrecomputedOptTable(ArrayRef<Info> OptionInfos,
ArrayRef<StringLiteral> PrefixesTable,
bool IgnoreCase = false)
: OptTable(OptionInfos, IgnoreCase), PrefixesUnion(PrefixesTable) {
buildPrefixChars();
}
ArrayRef<StringLiteral> getPrefixesUnion() const final {
return PrefixesUnion;
}
};
} // end namespace opt
} // end namespace llvm
#endif // LLVM_OPTION_OPTTABLE_H