include/llvm/Option/OptTable.h

   1 //===- OptTable.h - Option Table --------------------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef LLVM_OPTION_OPTTABLE_H
  10 #define LLVM_OPTION_OPTTABLE_H
  11
  12 #include "llvm/ADT/ArrayRef.h"
  13 #include "llvm/ADT/StringRef.h"
  14 #include "llvm/ADT/StringSet.h"
  15 #include "llvm/Option/OptSpecifier.h"
  16 #include <cassert>
  17 #include <string>
  18 #include <vector>
  19
  20 namespace llvm {
  21
  22 class raw_ostream;
  23
  24 namespace opt {
  25
  26 class Arg;
  27 class ArgList;
  28 class InputArgList;
  29 class Option;
  30
  31 /// Provide access to the Option info table.
  32 ///
  33 /// The OptTable class provides a layer of indirection which allows Option
  34 /// instance to be created lazily. In the common case, only a few options will
  35 /// be needed at runtime; the OptTable class maintains enough information to
  36 /// parse command lines without instantiating Options, while letting other
  37 /// parts of the driver still use Option instances where convenient.
  38 class OptTable {
  39 public:
  40   /// Entry for a single option instance in the option data table.
  41   struct Info {
  42     /// A null terminated array of prefix strings to apply to name while
  43     /// matching.
  44     const char *const *Prefixes;
  45     const char *Name;
  46     const char *HelpText;
  47     const char *MetaVar;
  48     unsigned ID;
  49     unsigned char Kind;
  50     unsigned char Param;
  51     unsigned short Flags;
  52     unsigned short GroupID;
  53     unsigned short AliasID;
  54     const char *AliasArgs;
  55     const char *Values;
  56   };
  57
  58 private:
  59   /// The option information table.
  60   std::vector<Info> OptionInfos;
  61   bool IgnoreCase;
  62
  63   unsigned TheInputOptionID = 0;
  64   unsigned TheUnknownOptionID = 0;
  65
  66   /// The index of the first option which can be parsed (i.e., is not a
  67   /// special option like 'input' or 'unknown', and is not an option group).
  68   unsigned FirstSearchableIndex = 0;
  69
  70   /// The union of all option prefixes. If an argument does not begin with
  71   /// one of these, it is an input.
  72   StringSet<> PrefixesUnion;
  73   std::string PrefixChars;
  74
  75 private:
  76   const Info &getInfo(OptSpecifier Opt) const {
  77     unsigned id = Opt.getID();
  78     assert(id > 0 && id - 1 < getNumOptions() && "Invalid Option ID.");
  79     return OptionInfos[id - 1];
  80   }
  81
  82 protected:
  83   OptTable(ArrayRef<Info> OptionInfos, bool IgnoreCase = false);
  84
  85 public:
  86   ~OptTable();
  87
  88   /// Return the total number of option classes.
  89   unsigned getNumOptions() const { return OptionInfos.size(); }
  90
  91   /// Get the given Opt's Option instance, lazily creating it
  92   /// if necessary.
  93   ///
  94   /// \return The option, or null for the INVALID option id.
  95   const Option getOption(OptSpecifier Opt) const;
  96
  97   /// Lookup the name of the given option.
  98   const char *getOptionName(OptSpecifier id) const {
  99     return getInfo(id).Name;
 100   }
 101
 102   /// Get the kind of the given option.
 103   unsigned getOptionKind(OptSpecifier id) const {
 104     return getInfo(id).Kind;
 105   }
 106
 107   /// Get the group id for the given option.
 108   unsigned getOptionGroupID(OptSpecifier id) const {
 109     return getInfo(id).GroupID;
 110   }
 111
 112   /// Get the help text to use to describe this option.
 113   const char *getOptionHelpText(OptSpecifier id) const {
 114     return getInfo(id).HelpText;
 115   }
 116
 117   /// Get the meta-variable name to use when describing
 118   /// this options values in the help text.
 119   const char *getOptionMetaVar(OptSpecifier id) const {
 120     return getInfo(id).MetaVar;
 121   }
 122
 123   /// Find possible value for given flags. This is used for shell
 124   /// autocompletion.
 125   ///
 126   /// \param [in] Option - Key flag like "-stdlib=" when "-stdlib=l"
 127   /// was passed to clang.
 128   ///
 129   /// \param [in] Arg - Value which we want to autocomplete like "l"
 130   /// when "-stdlib=l" was passed to clang.
 131   ///
 132   /// \return The vector of possible values.
 133   std::vector<std::string> suggestValueCompletions(StringRef Option,
 134                                                    StringRef Arg) const;
 135
 136   /// Find flags from OptTable which starts with Cur.
 137   ///
 138   /// \param [in] Cur - String prefix that all returned flags need
 139   //  to start with.
 140   ///
 141   /// \return The vector of flags which start with Cur.
 142   std::vector<std::string> findByPrefix(StringRef Cur,
 143                                         unsigned short DisableFlags) const;
 144
 145   /// Find the OptTable option that most closely matches the given string.
 146   ///
 147   /// \param [in] Option - A string, such as "-stdlibs=l", that represents user
 148   /// input of an option that may not exist in the OptTable. Note that the
 149   /// string includes prefix dashes "-" as well as values "=l".
 150   /// \param [out] NearestString - The nearest option string found in the
 151   /// OptTable.
 152   /// \param [in] FlagsToInclude - Only find options with any of these flags.
 153   /// Zero is the default, which includes all flags.
 154   /// \param [in] FlagsToExclude - Don't find options with this flag. Zero
 155   /// is the default, and means exclude nothing.
 156   /// \param [in] MinimumLength - Don't find options shorter than this length.
 157   /// For example, a minimum length of 3 prevents "-x" from being considered
 158   /// near to "-S".
 159   ///
 160   /// \return The edit distance of the nearest string found.
 161   unsigned findNearest(StringRef Option, std::string &NearestString,
 162                        unsigned FlagsToInclude = 0, unsigned FlagsToExclude = 0,
 163                        unsigned MinimumLength = 4) const;
 164
 165   /// Add Values to Option's Values class
 166   ///
 167   /// \param [in] Option - Prefix + Name of the flag which Values will be
 168   ///  changed. For example, "-analyzer-checker".
 169   /// \param [in] Values - String of Values seperated by ",", such as
 170   ///  "foo, bar..", where foo and bar is the argument which the Option flag
 171   ///  takes
 172   ///
 173   /// \return true in success, and false in fail.
 174   bool addValues(const char *Option, const char *Values);
 175
 176   /// Parse a single argument; returning the new argument and
 177   /// updating Index.
 178   ///
 179   /// \param [in,out] Index - The current parsing position in the argument
 180   /// string list; on return this will be the index of the next argument
 181   /// string to parse.
 182   /// \param [in] FlagsToInclude - Only parse options with any of these flags.
 183   /// Zero is the default which includes all flags.
 184   /// \param [in] FlagsToExclude - Don't parse options with this flag.  Zero
 185   /// is the default and means exclude nothing.
 186   ///
 187   /// \return The parsed argument, or 0 if the argument is missing values
 188   /// (in which case Index still points at the conceptual next argument string
 189   /// to parse).
 190   Arg *ParseOneArg(const ArgList &Args, unsigned &Index,
 191                    unsigned FlagsToInclude = 0,
 192                    unsigned FlagsToExclude = 0) const;
 193
 194   /// Parse an list of arguments into an InputArgList.
 195   ///
 196   /// The resulting InputArgList will reference the strings in [\p ArgBegin,
 197   /// \p ArgEnd), and their lifetime should extend past that of the returned
 198   /// InputArgList.
 199   ///
 200   /// The only error that can occur in this routine is if an argument is
 201   /// missing values; in this case \p MissingArgCount will be non-zero.
 202   ///
 203   /// \param MissingArgIndex - On error, the index of the option which could
 204   /// not be parsed.
 205   /// \param MissingArgCount - On error, the number of missing options.
 206   /// \param FlagsToInclude - Only parse options with any of these flags.
 207   /// Zero is the default which includes all flags.
 208   /// \param FlagsToExclude - Don't parse options with this flag.  Zero
 209   /// is the default and means exclude nothing.
 210   /// \return An InputArgList; on error this will contain all the options
 211   /// which could be parsed.
 212   InputArgList ParseArgs(ArrayRef<const char *> Args, unsigned &MissingArgIndex,
 213                          unsigned &MissingArgCount, unsigned FlagsToInclude = 0,
 214                          unsigned FlagsToExclude = 0) const;
 215
 216   /// Render the help text for an option table.
 217   ///
 218   /// \param OS - The stream to write the help text to.
 219   /// \param Usage - USAGE: Usage
 220   /// \param Title - OVERVIEW: Title
 221   /// \param FlagsToInclude - If non-zero, only include options with any
 222   ///                         of these flags set.
 223   /// \param FlagsToExclude - Exclude options with any of these flags set.
 224   /// \param ShowAllAliases - If true, display all options including aliases
 225   ///                         that don't have help texts. By default, we display
 226   ///                         only options that are not hidden and have help
 227   ///                         texts.
 228   void PrintHelp(raw_ostream &OS, const char *Usage, const char *Title,
 229                  unsigned FlagsToInclude, unsigned FlagsToExclude,
 230                  bool ShowAllAliases) const;
 231
 232   void PrintHelp(raw_ostream &OS, const char *Usage, const char *Title,
 233                  bool ShowHidden = false, bool ShowAllAliases = false) const;
 234 };
 235
 236 } // end namespace opt
 237
 238 } // end namespace llvm
 239
 240 #endif // LLVM_OPTION_OPTTABLE_H