tools/llvm-rc/ResourceScriptParser.h

   1 //===-- ResourceScriptParser.h ----------------------------------*- C++-*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===---------------------------------------------------------------------===//
   9 //
  10 // This defines the RC scripts parser. It takes a sequence of RC tokens
  11 // and then provides the method to parse the resources one by one.
  12 //
  13 //===---------------------------------------------------------------------===//
  14
  15 #ifndef LLVM_TOOLS_LLVMRC_RESOURCESCRIPTPARSER_H
  16 #define LLVM_TOOLS_LLVMRC_RESOURCESCRIPTPARSER_H
  17
  18 #include "ResourceScriptStmt.h"
  19 #include "ResourceScriptToken.h"
  20
  21 #include "llvm/Support/Compiler.h"
  22 #include "llvm/Support/raw_ostream.h"
  23
  24 #include <system_error>
  25 #include <vector>
  26
  27 namespace llvm {
  28 namespace opt {
  29 class InputArgList;
  30 }
  31 namespace rc {
  32
  33 class RCParser {
  34 public:
  35   using LocIter = std::vector<RCToken>::iterator;
  36   using ParseType = Expected<std::unique_ptr<RCResource>>;
  37   using ParseOptionType = Expected<std::unique_ptr<OptionalStmt>>;
  38
  39   // Class describing a single failure of parser.
  40   class ParserError : public ErrorInfo<ParserError> {
  41   public:
  42     ParserError(const Twine &Expected, const LocIter CurLoc, const LocIter End);
  43
  44     void log(raw_ostream &OS) const override { OS << CurMessage; }
  45     std::error_code convertToErrorCode() const override {
  46       return std::make_error_code(std::errc::invalid_argument);
  47     }
  48     const std::string &getMessage() const { return CurMessage; }
  49
  50     static char ID; // Keep llvm::Error happy.
  51
  52   private:
  53     std::string CurMessage;
  54     LocIter ErrorLoc, FileEnd;
  55   };
  56
  57   explicit RCParser(std::vector<RCToken> TokenList);
  58
  59   // Reads and returns a single resource definition, or error message if any
  60   // occurred.
  61   ParseType parseSingleResource();
  62
  63   bool isEof() const;
  64
  65 private:
  66   using Kind = RCToken::Kind;
  67
  68   // Checks if the current parser state points to the token of type TokenKind.
  69   bool isNextTokenKind(Kind TokenKind) const;
  70
  71   // These methods assume that the parser is not in EOF state.
  72
  73   // Take a look at the current token. Do not fetch it.
  74   const RCToken &look() const;
  75   // Read the current token and advance the state by one token.
  76   const RCToken &read();
  77   // Advance the state by one token, discarding the current token.
  78   void consume();
  79
  80   // The following methods try to read a single token, check if it has the
  81   // correct type and then parse it.
  82   // Each integer can be written as an arithmetic expression producing an
  83   // unsigned 32-bit integer.
  84   Expected<RCInt> readInt();               // Parse an integer.
  85   Expected<StringRef> readString();        // Parse a string.
  86   Expected<StringRef> readIdentifier();    // Parse an identifier.
  87   Expected<IntOrString> readIntOrString(); // Parse an integer or a string.
  88   Expected<IntOrString> readTypeOrName();  // Parse an integer or an identifier.
  89
  90   // Helper integer expression parsing methods.
  91   Expected<RCInt> parseIntExpr1();
  92   Expected<RCInt> parseIntExpr2();
  93
  94   // Advance the state by one, discarding the current token.
  95   // If the discarded token had an incorrect type, fail.
  96   Error consumeType(Kind TokenKind);
  97
  98   // Check the current token type. If it's TokenKind, discard it.
  99   // Return true if the parser consumed this token successfully.
 100   bool consumeOptionalType(Kind TokenKind);
 101
 102   // Read at least MinCount, and at most MaxCount integers separated by
 103   // commas. The parser stops reading after fetching MaxCount integers
 104   // or after an error occurs. Whenever the parser reads a comma, it
 105   // expects an integer to follow.
 106   Expected<SmallVector<RCInt, 8>> readIntsWithCommas(size_t MinCount,
 107                                                      size_t MaxCount);
 108
 109   // Read an unknown number of flags preceded by commas. Each correct flag
 110   // has an entry in FlagDesc array of length NumFlags. In case i-th
 111   // flag (0-based) has been read, the result is OR-ed with FlagValues[i].
 112   // As long as parser has a comma to read, it expects to be fed with
 113   // a correct flag afterwards.
 114   Expected<uint32_t> parseFlags(ArrayRef<StringRef> FlagDesc,
 115                                 ArrayRef<uint32_t> FlagValues);
 116
 117   // Reads a set of optional statements. These can change the behavior of
 118   // a number of resource types (e.g. STRINGTABLE, MENU or DIALOG) if provided
 119   // before the main block with the contents of the resource.
 120   // Usually, resources use a basic set of optional statements:
 121   //    CHARACTERISTICS, LANGUAGE, VERSION
 122   // However, DIALOG and DIALOGEX extend this list by the following items:
 123   //    CAPTION, CLASS, EXSTYLE, FONT, MENU, STYLE
 124   // UseExtendedStatements flag (off by default) allows the parser to read
 125   // the additional types of statements.
 126   //
 127   // Ref (to the list of all optional statements):
 128   //    msdn.microsoft.com/en-us/library/windows/desktop/aa381002(v=vs.85).aspx
 129   enum class OptStmtType { BasicStmt, DialogStmt, DialogExStmt };
 130
 131   Expected<OptionalStmtList>
 132   parseOptionalStatements(OptStmtType StmtsType = OptStmtType::BasicStmt);
 133
 134   // Read a single optional statement.
 135   Expected<std::unique_ptr<OptionalStmt>>
 136   parseSingleOptionalStatement(OptStmtType StmtsType = OptStmtType::BasicStmt);
 137
 138   // Top-level resource parsers.
 139   ParseType parseLanguageResource();
 140   ParseType parseAcceleratorsResource();
 141   ParseType parseCursorResource();
 142   ParseType parseDialogResource(bool IsExtended);
 143   ParseType parseIconResource();
 144   ParseType parseHTMLResource();
 145   ParseType parseMenuResource();
 146   ParseType parseStringTableResource();
 147   ParseType parseUserDefinedResource(IntOrString Type);
 148   ParseType parseVersionInfoResource();
 149
 150   // Helper DIALOG parser - a single control.
 151   Expected<Control> parseControl();
 152
 153   // Helper MENU parser.
 154   Expected<MenuDefinitionList> parseMenuItemsList();
 155
 156   // Helper VERSIONINFO parser - read the contents of a single BLOCK statement,
 157   // from BEGIN to END.
 158   Expected<std::unique_ptr<VersionInfoBlock>>
 159   parseVersionInfoBlockContents(StringRef BlockName);
 160   // Helper VERSIONINFO parser - read either VALUE or BLOCK statement.
 161   Expected<std::unique_ptr<VersionInfoStmt>> parseVersionInfoStmt();
 162   // Helper VERSIONINFO parser - read fixed VERSIONINFO statements.
 163   Expected<VersionInfoResource::VersionInfoFixed> parseVersionInfoFixed();
 164
 165   // Optional statement parsers.
 166   ParseOptionType parseLanguageStmt();
 167   ParseOptionType parseCharacteristicsStmt();
 168   ParseOptionType parseVersionStmt();
 169   ParseOptionType parseCaptionStmt();
 170   ParseOptionType parseFontStmt(OptStmtType DialogType);
 171   ParseOptionType parseStyleStmt();
 172
 173   // Raises an error. If IsAlreadyRead = false (default), this complains about
 174   // the token that couldn't be parsed. If the flag is on, this complains about
 175   // the correctly read token that makes no sense (that is, the current parser
 176   // state is beyond the erroneous token.)
 177   Error getExpectedError(const Twine &Message, bool IsAlreadyRead = false);
 178
 179   std::vector<RCToken> Tokens;
 180   LocIter CurLoc;
 181   const LocIter End;
 182 };
 183
 184 } // namespace rc
 185 } // namespace llvm
 186
 187 #endif