1 | //===- ScriptLexer.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 | #ifndef LLD_ELF_SCRIPT_LEXER_H |
10 | #define LLD_ELF_SCRIPT_LEXER_H |
11 | |
12 | #include "lld/Common/LLVM.h" |
13 | #include "llvm/ADT/DenseSet.h" |
14 | #include "llvm/ADT/SmallVector.h" |
15 | #include "llvm/ADT/StringRef.h" |
16 | #include "llvm/Support/MemoryBufferRef.h" |
17 | #include <vector> |
18 | |
19 | namespace lld::elf { |
20 | struct Ctx; |
21 | |
22 | class ScriptLexer { |
23 | protected: |
24 | struct Buffer { |
25 | // The remaining content to parse and the filename. |
26 | StringRef s, filename; |
27 | const char *begin = nullptr; |
28 | size_t lineNumber = 1; |
29 | // True if the script is opened as an absolute path under the --sysroot |
30 | // directory. |
31 | bool isUnderSysroot = false; |
32 | |
33 | Buffer() = default; |
34 | Buffer(Ctx &ctx, MemoryBufferRef mb); |
35 | }; |
36 | Ctx &ctx; |
37 | // The current buffer and parent buffers due to INCLUDE. |
38 | Buffer curBuf; |
39 | SmallVector<Buffer, 0> buffers; |
40 | |
41 | // Used to detect INCLUDE() cycles. |
42 | llvm::DenseSet<StringRef> activeFilenames; |
43 | |
44 | enum class State { |
45 | Script, |
46 | Expr, |
47 | }; |
48 | |
49 | struct Token { |
50 | StringRef str; |
51 | explicit operator bool() const { return !str.empty(); } |
52 | operator StringRef() const { return str; } |
53 | }; |
54 | |
55 | // The token before the last next(). |
56 | StringRef prevTok; |
57 | // Rules for what is a token are different when we are in an expression. |
58 | // curTok holds the cached return value of peek() and is invalid when the |
59 | // expression state changes. |
60 | StringRef curTok; |
61 | size_t prevTokLine = 1; |
62 | // The lex state when curTok is cached. |
63 | State curTokState = State::Script; |
64 | State lexState = State::Script; |
65 | bool eof = false; |
66 | |
67 | public: |
68 | explicit ScriptLexer(Ctx &ctx, MemoryBufferRef mb); |
69 | |
70 | void setError(const Twine &msg); |
71 | void lex(); |
72 | StringRef skipSpace(StringRef s); |
73 | bool atEOF(); |
74 | StringRef next(); |
75 | StringRef peek(); |
76 | void skip(); |
77 | bool consume(StringRef tok); |
78 | void expect(StringRef expect); |
79 | Token till(StringRef tok); |
80 | std::string getCurrentLocation(); |
81 | MemoryBufferRef getCurrentMB(); |
82 | |
83 | std::vector<MemoryBufferRef> mbs; |
84 | |
85 | private: |
86 | StringRef getLine(); |
87 | size_t getColumnNumber(); |
88 | }; |
89 | |
90 | } // namespace lld::elf |
91 | |
92 | #endif |
93 | |