xref: /llvm-project/llvm/tools/llvm-rc/ResourceScriptParser.h (revision b5f39a05a329534979572781b10326c60b0bdc9e)
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<uint32_t> 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<uint32_t> parseIntExpr1();
90   Expected<uint32_t> 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<uint32_t, 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 i-th bit of the result is set.
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 
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   Expected<OptionalStmtList>
127   parseOptionalStatements(bool UseExtendedStatements = false);
128 
129   // Read a single optional statement.
130   Expected<std::unique_ptr<OptionalStmt>>
131   parseSingleOptionalStatement(bool UseExtendedStatements = false);
132 
133   // Top-level resource parsers.
134   ParseType parseLanguageResource();
135   ParseType parseAcceleratorsResource();
136   ParseType parseCursorResource();
137   ParseType parseDialogResource(bool IsExtended);
138   ParseType parseIconResource();
139   ParseType parseHTMLResource();
140   ParseType parseMenuResource();
141   ParseType parseStringTableResource();
142   ParseType parseUserDefinedResource(IntOrString Type);
143   ParseType parseVersionInfoResource();
144 
145   // Helper DIALOG parser - a single control.
146   Expected<Control> parseControl();
147 
148   // Helper MENU parser.
149   Expected<MenuDefinitionList> parseMenuItemsList();
150 
151   // Helper VERSIONINFO parser - read the contents of a single BLOCK statement,
152   // from BEGIN to END.
153   Expected<std::unique_ptr<VersionInfoBlock>>
154   parseVersionInfoBlockContents(StringRef BlockName);
155   // Helper VERSIONINFO parser - read either VALUE or BLOCK statement.
156   Expected<std::unique_ptr<VersionInfoStmt>> parseVersionInfoStmt();
157   // Helper VERSIONINFO parser - read fixed VERSIONINFO statements.
158   Expected<VersionInfoResource::VersionInfoFixed> parseVersionInfoFixed();
159 
160   // Optional statement parsers.
161   ParseOptionType parseLanguageStmt();
162   ParseOptionType parseCharacteristicsStmt();
163   ParseOptionType parseVersionStmt();
164   ParseOptionType parseCaptionStmt();
165   ParseOptionType parseFontStmt();
166   ParseOptionType parseStyleStmt();
167 
168   // Raises an error. If IsAlreadyRead = false (default), this complains about
169   // the token that couldn't be parsed. If the flag is on, this complains about
170   // the correctly read token that makes no sense (that is, the current parser
171   // state is beyond the erroneous token.)
172   Error getExpectedError(const Twine Message, bool IsAlreadyRead = false);
173 
174   std::vector<RCToken> Tokens;
175   LocIter CurLoc;
176   const LocIter End;
177 };
178 
179 } // namespace rc
180 } // namespace llvm
181 
182 #endif
183