llvm/tools/llvm-rc/ResourceScriptParser.h

   1 //===-- ResourceScriptParser.h ----------------------------------*- 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 // This defines the RC scripts parser. It takes a sequence of RC tokens
  10 // and then provides the method to parse the resources one by one.
  11 //
  12 //===---------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_TOOLS_LLVMRC_RESOURCESCRIPTPARSER_H
  15 #define LLVM_TOOLS_LLVMRC_RESOURCESCRIPTPARSER_H
  16
  17 #include "ResourceScriptStmt.h"
  18 #include "ResourceScriptToken.h"
  19
  20 #include "llvm/Support/Compiler.h"
  21 #include "llvm/Support/raw_ostream.h"
  22
  23 #include <system_error>
  24 #include <vector>
  25
  26 namespace llvm {
  27 namespace rc {
  28
  29 class RCParser {
  30 public:
  31   using LocIter = std::vector<RCToken>::iterator;
  32   using ParseType = Expected<std::unique_ptr<RCResource>>;
  33   using ParseOptionType = Expected<std::unique_ptr<OptionalStmt>>;
  34
  35   // Class describing a single failure of parser.
  36   class ParserError : public ErrorInfo<ParserError> {
  37   public:
  38     ParserError(const Twine &Expected, const LocIter CurLoc, const LocIter End);
  39
  40     void log(raw_ostream &OS) const override { OS << CurMessage; }
  41     std::error_code convertToErrorCode() const override {
  42       return std::make_error_code(std::errc::invalid_argument);
  43     }
  44     const std::string &getMessage() const { return CurMessage; }
  45
  46     static char ID; // Keep llvm::Error happy.
  47
  48   private:
  49     std::string CurMessage;
  50     LocIter ErrorLoc, FileEnd;
  51   };
  52
  53   explicit RCParser(std::vector<RCToken> TokenList);
  54
  55   // Reads and returns a single resource definition, or error message if any
  56   // occurred.
  57   ParseType parseSingleResource();
  58
  59   bool isEof() const;
  60
  61 private:
  62   using Kind = RCToken::Kind;
  63
  64   // Checks if the current parser state points to the token of type TokenKind.
  65   bool isNextTokenKind(Kind TokenKind) const;
  66
  67   // These methods assume that the parser is not in EOF state.
  68
  69   // Take a look at the current token. Do not fetch it.
  70   const RCToken &look() const;
  71   // Read the current token and advance the state by one token.
  72   const RCToken &read();
  73   // Advance the state by one token, discarding the current token.
  74   void consume();
  75
  76   // The following methods try to read a single token, check if it has the
  77   // correct type and then parse it.
  78   // Each integer can be written as an arithmetic expression producing an
  79   // unsigned 32-bit integer.
  80   Expected<RCInt> readInt();               // Parse an integer.
  81   Expected<StringRef> readString();        // Parse a string.
  82   Expected<StringRef> readIdentifier();    // Parse an identifier.
  83   Expected<StringRef> readFilename();      // Parse a filename.
  84   Expected<IntOrString> readIntOrString(); // Parse an integer or a string.
  85   Expected<IntOrString> readTypeOrName();  // Parse an integer or an identifier.
  86
  87   // Helper integer expression parsing methods.
  88   Expected<IntWithNotMask> parseIntExpr1();
  89   Expected<IntWithNotMask> parseIntExpr2();
  90
  91   // Advance the state by one, discarding the current token.
  92   // If the discarded token had an incorrect type, fail.
  93   Error consumeType(Kind TokenKind);
  94
  95   // Check the current token type. If it's TokenKind, discard it.
  96   // Return true if the parser consumed this token successfully.
  97   bool consumeOptionalType(Kind TokenKind);
  98
  99   // Read at least MinCount, and at most MaxCount integers separated by
 100   // commas. The parser stops reading after fetching MaxCount integers
 101   // or after an error occurs. Whenever the parser reads a comma, it
 102   // expects an integer to follow.
 103   Expected<SmallVector<RCInt, 8>> readIntsWithCommas(size_t MinCount,
 104                                                      size_t MaxCount);
 105
 106   // Read an unknown number of flags preceded by commas. Each correct flag
 107   // has an entry in FlagDesc array of length NumFlags. In case i-th
 108   // flag (0-based) has been read, the result is OR-ed with FlagValues[i].
 109   // As long as parser has a comma to read, it expects to be fed with
 110   // a correct flag afterwards.
 111   Expected<uint32_t> parseFlags(ArrayRef<StringRef> FlagDesc,
 112                                 ArrayRef<uint32_t> FlagValues);
 113
 114   // Reads a set of optional statements. These can change the behavior of
 115   // a number of resource types (e.g. STRINGTABLE, MENU or DIALOG) if provided
 116   // before the main block with the contents of the resource.
 117   // Usually, resources use a basic set of optional statements:
 118   //    CHARACTERISTICS, LANGUAGE, VERSION
 119   // However, DIALOG and DIALOGEX extend this list by the following items:
 120   //    CAPTION, CLASS, EXSTYLE, FONT, MENU, STYLE
 121   // UseExtendedStatements flag (off by default) allows the parser to read
 122   // the additional types of statements.
 123   //
 124   // Ref (to the list of all optional statements):
 125   //    msdn.microsoft.com/en-us/library/windows/desktop/aa381002(v=vs.85).aspx
 126   enum class OptStmtType { BasicStmt, DialogStmt, DialogExStmt };
 127
 128   uint16_t parseMemoryFlags(uint16_t DefaultFlags);
 129
 130   Expected<OptionalStmtList>
 131   parseOptionalStatements(OptStmtType StmtsType = OptStmtType::BasicStmt);
 132
 133   // Read a single optional statement.
 134   Expected<std::unique_ptr<OptionalStmt>>
 135   parseSingleOptionalStatement(OptStmtType StmtsType = OptStmtType::BasicStmt);
 136
 137   // Top-level resource parsers.
 138   ParseType parseLanguageResource();
 139   ParseType parseAcceleratorsResource();
 140   ParseType parseBitmapResource();
 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 parseClassStmt();
 171   ParseOptionType parseExStyleStmt();
 172   ParseOptionType parseFontStmt(OptStmtType DialogType);
 173   ParseOptionType parseStyleStmt();
 174
 175   // Raises an error. If IsAlreadyRead = false (default), this complains about
 176   // the token that couldn't be parsed. If the flag is on, this complains about
 177   // the correctly read token that makes no sense (that is, the current parser
 178   // state is beyond the erroneous token.)
 179   Error getExpectedError(const Twine &Message, bool IsAlreadyRead = false);
 180
 181   std::vector<RCToken> Tokens;
 182   LocIter CurLoc;
 183   const LocIter End;
 184 };
 185
 186 } // namespace rc
 187 } // namespace llvm
 188
 189 #endif