xref: /llvm-project/llvm/tools/llvm-rc/ResourceScriptParser.h (revision 07bc04ff384b367d6e4bb318fbad8e9c6b0a304e)
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 rc {
29 
30 class RCParser {
31 public:
32   using LocIter = std::vector<RCToken>::iterator;
33   using ParseType = Expected<std::unique_ptr<RCResource>>;
34   using ParseOptionType = Expected<std::unique_ptr<OptionalStmt>>;
35 
36   // Class describing a single failure of parser.
37   class ParserError : public ErrorInfo<ParserError> {
38   public:
39     ParserError(Twine Expected, const LocIter CurLoc, const LocIter End);
40 
41     void log(raw_ostream &OS) const override { OS << CurMessage; }
42     std::error_code convertToErrorCode() const override {
43       return std::make_error_code(std::errc::invalid_argument);
44     }
45     const std::string &getMessage() const { return CurMessage; }
46 
47     static char ID; // Keep llvm::Error happy.
48 
49   private:
50     std::string CurMessage;
51     LocIter ErrorLoc, FileEnd;
52   };
53 
54   RCParser(const std::vector<RCToken> &TokenList);
55   RCParser(std::vector<RCToken> &&TokenList);
56 
57   // Reads and returns a single resource definition, or error message if any
58   // occurred.
59   ParseType parseSingleResource();
60 
61   bool isEof() const;
62 
63 private:
64   using Kind = RCToken::Kind;
65 
66   // Checks if the current parser state points to the token of type TokenKind.
67   bool isNextTokenKind(Kind TokenKind) const;
68 
69   // These methods assume that the parser is not in EOF state.
70 
71   // Take a look at the current token. Do not fetch it.
72   const RCToken &look() const;
73   // Read the current token and advance the state by one token.
74   const RCToken &read();
75   // Advance the state by one token, discarding the current token.
76   void consume();
77 
78   // The following methods try to read a single token, check if it has the
79   // correct type and then parse it.
80   // Each integer can be written as an arithmetic expression producing an
81   // unsigned 32-bit integer.
82   Expected<RCInt> readInt();               // Parse an integer.
83   Expected<StringRef> readString();        // Parse a string.
84   Expected<StringRef> readIdentifier();    // Parse an identifier.
85   Expected<IntOrString> readIntOrString(); // Parse an integer or a string.
86   Expected<IntOrString> readTypeOrName();  // Parse an integer or an identifier.
87 
88   // Helper integer expression parsing methods.
89   Expected<RCInt> parseIntExpr1();
90   Expected<RCInt> parseIntExpr2();
91 
92   // Advance the state by one, discarding the current token.
93   // If the discarded token had an incorrect type, fail.
94   Error consumeType(Kind TokenKind);
95 
96   // Check the current token type. If it's TokenKind, discard it.
97   // Return true if the parser consumed this token successfully.
98   bool consumeOptionalType(Kind TokenKind);
99 
100   // Read at least MinCount, and at most MaxCount integers separated by
101   // commas. The parser stops reading after fetching MaxCount integers
102   // or after an error occurs. Whenever the parser reads a comma, it
103   // expects an integer to follow.
104   Expected<SmallVector<RCInt, 8>> readIntsWithCommas(size_t MinCount,
105                                                      size_t MaxCount);
106 
107   // Read an unknown number of flags preceded by commas. Each correct flag
108   // has an entry in FlagDesc array of length NumFlags. In case i-th
109   // flag (0-based) has been read, the result is OR-ed with FlagValues[i].
110   // As long as parser has a comma to read, it expects to be fed with
111   // a correct flag afterwards.
112   Expected<uint32_t> parseFlags(ArrayRef<StringRef> FlagDesc,
113                                 ArrayRef<uint32_t> FlagValues);
114 
115   // Reads a set of optional statements. These can change the behavior of
116   // a number of resource types (e.g. STRINGTABLE, MENU or DIALOG) if provided
117   // before the main block with the contents of the resource.
118   // Usually, resources use a basic set of optional statements:
119   //    CHARACTERISTICS, LANGUAGE, VERSION
120   // However, DIALOG and DIALOGEX extend this list by the following items:
121   //    CAPTION, CLASS, EXSTYLE, FONT, MENU, STYLE
122   // UseExtendedStatements flag (off by default) allows the parser to read
123   // the additional types of statements.
124   //
125   // Ref (to the list of all optional statements):
126   //    msdn.microsoft.com/en-us/library/windows/desktop/aa381002(v=vs.85).aspx
127   enum class OptStmtType { BasicStmt, DialogStmt, DialogExStmt };
128 
129   Expected<OptionalStmtList>
130   parseOptionalStatements(OptStmtType StmtsType = OptStmtType::BasicStmt);
131 
132   // Read a single optional statement.
133   Expected<std::unique_ptr<OptionalStmt>>
134   parseSingleOptionalStatement(OptStmtType StmtsType = OptStmtType::BasicStmt);
135 
136   // Top-level resource parsers.
137   ParseType parseLanguageResource();
138   ParseType parseAcceleratorsResource();
139   ParseType parseCursorResource();
140   ParseType parseDialogResource(bool IsExtended);
141   ParseType parseIconResource();
142   ParseType parseHTMLResource();
143   ParseType parseMenuResource();
144   ParseType parseStringTableResource();
145   ParseType parseUserDefinedResource(IntOrString Type);
146   ParseType parseVersionInfoResource();
147 
148   // Helper DIALOG parser - a single control.
149   Expected<Control> parseControl();
150 
151   // Helper MENU parser.
152   Expected<MenuDefinitionList> parseMenuItemsList();
153 
154   // Helper VERSIONINFO parser - read the contents of a single BLOCK statement,
155   // from BEGIN to END.
156   Expected<std::unique_ptr<VersionInfoBlock>>
157   parseVersionInfoBlockContents(StringRef BlockName);
158   // Helper VERSIONINFO parser - read either VALUE or BLOCK statement.
159   Expected<std::unique_ptr<VersionInfoStmt>> parseVersionInfoStmt();
160   // Helper VERSIONINFO parser - read fixed VERSIONINFO statements.
161   Expected<VersionInfoResource::VersionInfoFixed> parseVersionInfoFixed();
162 
163   // Optional statement parsers.
164   ParseOptionType parseLanguageStmt();
165   ParseOptionType parseCharacteristicsStmt();
166   ParseOptionType parseVersionStmt();
167   ParseOptionType parseCaptionStmt();
168   ParseOptionType parseFontStmt(OptStmtType DialogType);
169   ParseOptionType parseStyleStmt();
170 
171   // Raises an error. If IsAlreadyRead = false (default), this complains about
172   // the token that couldn't be parsed. If the flag is on, this complains about
173   // the correctly read token that makes no sense (that is, the current parser
174   // state is beyond the erroneous token.)
175   Error getExpectedError(const Twine Message, bool IsAlreadyRead = false);
176 
177   std::vector<RCToken> Tokens;
178   LocIter CurLoc;
179   const LocIter End;
180 };
181 
182 } // namespace rc
183 } // namespace llvm
184 
185 #endif
186