xref: /llvm-project/llvm/tools/llvm-rc/ResourceScriptParser.h (revision 514b7105b52fb98939f2b982651ec876582250f4)
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(const 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(std::vector<RCToken> TokenList);
55 
56   // Reads and returns a single resource definition, or error message if any
57   // occurred.
58   ParseType parseSingleResource();
59 
60   bool isEof() const;
61 
62 private:
63   using Kind = RCToken::Kind;
64 
65   // Checks if the current parser state points to the token of type TokenKind.
66   bool isNextTokenKind(Kind TokenKind) const;
67 
68   // These methods assume that the parser is not in EOF state.
69 
70   // Take a look at the current token. Do not fetch it.
71   const RCToken &look() const;
72   // Read the current token and advance the state by one token.
73   const RCToken &read();
74   // Advance the state by one token, discarding the current token.
75   void consume();
76 
77   // The following methods try to read a single token, check if it has the
78   // correct type and then parse it.
79   // Each integer can be written as an arithmetic expression producing an
80   // unsigned 32-bit integer.
81   Expected<RCInt> readInt();               // Parse an integer.
82   Expected<StringRef> readString();        // Parse a string.
83   Expected<StringRef> readIdentifier();    // Parse an identifier.
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<RCInt> parseIntExpr1();
89   Expected<RCInt> 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   Expected<OptionalStmtList>
129   parseOptionalStatements(OptStmtType StmtsType = OptStmtType::BasicStmt);
130 
131   // Read a single optional statement.
132   Expected<std::unique_ptr<OptionalStmt>>
133   parseSingleOptionalStatement(OptStmtType StmtsType = OptStmtType::BasicStmt);
134 
135   // Top-level resource parsers.
136   ParseType parseLanguageResource();
137   ParseType parseAcceleratorsResource();
138   ParseType parseCursorResource();
139   ParseType parseDialogResource(bool IsExtended);
140   ParseType parseIconResource();
141   ParseType parseHTMLResource();
142   ParseType parseMenuResource();
143   ParseType parseStringTableResource();
144   ParseType parseUserDefinedResource(IntOrString Type);
145   ParseType parseVersionInfoResource();
146 
147   // Helper DIALOG parser - a single control.
148   Expected<Control> parseControl();
149 
150   // Helper MENU parser.
151   Expected<MenuDefinitionList> parseMenuItemsList();
152 
153   // Helper VERSIONINFO parser - read the contents of a single BLOCK statement,
154   // from BEGIN to END.
155   Expected<std::unique_ptr<VersionInfoBlock>>
156   parseVersionInfoBlockContents(StringRef BlockName);
157   // Helper VERSIONINFO parser - read either VALUE or BLOCK statement.
158   Expected<std::unique_ptr<VersionInfoStmt>> parseVersionInfoStmt();
159   // Helper VERSIONINFO parser - read fixed VERSIONINFO statements.
160   Expected<VersionInfoResource::VersionInfoFixed> parseVersionInfoFixed();
161 
162   // Optional statement parsers.
163   ParseOptionType parseLanguageStmt();
164   ParseOptionType parseCharacteristicsStmt();
165   ParseOptionType parseVersionStmt();
166   ParseOptionType parseCaptionStmt();
167   ParseOptionType parseFontStmt(OptStmtType DialogType);
168   ParseOptionType parseStyleStmt();
169 
170   // Raises an error. If IsAlreadyRead = false (default), this complains about
171   // the token that couldn't be parsed. If the flag is on, this complains about
172   // the correctly read token that makes no sense (that is, the current parser
173   // state is beyond the erroneous token.)
174   Error getExpectedError(const Twine &Message, bool IsAlreadyRead = false);
175 
176   std::vector<RCToken> Tokens;
177   LocIter CurLoc;
178   const LocIter End;
179 };
180 
181 } // namespace rc
182 } // namespace llvm
183 
184 #endif
185