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 opt {
  28 class InputArgList;
  29 }
  30 namespace rc {
  31
  32 class RCParser {
  33 public:
  34   using LocIter = std::vector<RCToken>::iterator;
  35   using ParseType = Expected<std::unique_ptr<RCResource>>;
  36   using ParseOptionType = Expected<std::unique_ptr<OptionalStmt>>;
  37
  38   // Class describing a single failure of parser.
  39   class ParserError : public ErrorInfo<ParserError> {
  40   public:
  41     ParserError(const Twine &Expected, const LocIter CurLoc, const LocIter End);
  42
  43     void log(raw_ostream &OS) const override { OS << CurMessage; }
  44     std::error_code convertToErrorCode() const override {
  45       return std::make_error_code(std::errc::invalid_argument);
  46     }
  47     const std::string &getMessage() const { return CurMessage; }
  48
  49     static char ID; // Keep llvm::Error happy.
  50
  51   private:
  52     std::string CurMessage;
  53     LocIter ErrorLoc, FileEnd;
  54   };
  55
  56   explicit RCParser(std::vector<RCToken> TokenList);
  57
  58   // Reads and returns a single resource definition, or error message if any
  59   // occurred.
  60   ParseType parseSingleResource();
  61
  62   bool isEof() const;
  63
  64 private:
  65   using Kind = RCToken::Kind;
  66
  67   // Checks if the current parser state points to the token of type TokenKind.
  68   bool isNextTokenKind(Kind TokenKind) const;
  69
  70   // These methods assume that the parser is not in EOF state.
  71
  72   // Take a look at the current token. Do not fetch it.
  73   const RCToken &look() const;
  74   // Read the current token and advance the state by one token.
  75   const RCToken &read();
  76   // Advance the state by one token, discarding the current token.
  77   void consume();
  78
  79   // The following methods try to read a single token, check if it has the
  80   // correct type and then parse it.
  81   // Each integer can be written as an arithmetic expression producing an
  82   // unsigned 32-bit integer.
  83   Expected<RCInt> readInt();               // Parse an integer.
  84   Expected<StringRef> readString();        // Parse a string.
  85   Expected<StringRef> readIdentifier();    // Parse an identifier.
  86   Expected<StringRef> readFilename();      // Parse a filename.
  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<IntWithNotMask> parseIntExpr1();
  92   Expected<IntWithNotMask> 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   uint16_t parseMemoryFlags(uint16_t DefaultFlags);
 132
 133   Expected<OptionalStmtList>
 134   parseOptionalStatements(OptStmtType StmtsType = OptStmtType::BasicStmt);
 135
 136   // Read a single optional statement.
 137   Expected<std::unique_ptr<OptionalStmt>>
 138   parseSingleOptionalStatement(OptStmtType StmtsType = OptStmtType::BasicStmt);
 139
 140   // Top-level resource parsers.
 141   ParseType parseLanguageResource();
 142   ParseType parseAcceleratorsResource();
 143   ParseType parseBitmapResource();
 144   ParseType parseCursorResource();
 145   ParseType parseDialogResource(bool IsExtended);
 146   ParseType parseIconResource();
 147   ParseType parseHTMLResource();
 148   ParseType parseMenuResource();
 149   ParseType parseStringTableResource();
 150   ParseType parseUserDefinedResource(IntOrString Type);
 151   ParseType parseVersionInfoResource();
 152
 153   // Helper DIALOG parser - a single control.
 154   Expected<Control> parseControl();
 155
 156   // Helper MENU parser.
 157   Expected<MenuDefinitionList> parseMenuItemsList();
 158
 159   // Helper VERSIONINFO parser - read the contents of a single BLOCK statement,
 160   // from BEGIN to END.
 161   Expected<std::unique_ptr<VersionInfoBlock>>
 162   parseVersionInfoBlockContents(StringRef BlockName);
 163   // Helper VERSIONINFO parser - read either VALUE or BLOCK statement.
 164   Expected<std::unique_ptr<VersionInfoStmt>> parseVersionInfoStmt();
 165   // Helper VERSIONINFO parser - read fixed VERSIONINFO statements.
 166   Expected<VersionInfoResource::VersionInfoFixed> parseVersionInfoFixed();
 167
 168   // Optional statement parsers.
 169   ParseOptionType parseLanguageStmt();
 170   ParseOptionType parseCharacteristicsStmt();
 171   ParseOptionType parseVersionStmt();
 172   ParseOptionType parseCaptionStmt();
 173   ParseOptionType parseClassStmt();
 174   ParseOptionType parseExStyleStmt();
 175   ParseOptionType parseFontStmt(OptStmtType DialogType);
 176   ParseOptionType parseStyleStmt();
 177
 178   // Raises an error. If IsAlreadyRead = false (default), this complains about
 179   // the token that couldn't be parsed. If the flag is on, this complains about
 180   // the correctly read token that makes no sense (that is, the current parser
 181   // state is beyond the erroneous token.)
 182   Error getExpectedError(const Twine &Message, bool IsAlreadyRead = false);
 183
 184   std::vector<RCToken> Tokens;
 185   LocIter CurLoc;
 186   const LocIter End;
 187 };
 188
 189 } // namespace rc
 190 } // namespace llvm
 191
 192 #endif