1 //===--- Serialization.h - Binary serialization of index data ----*- 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 file provides serialization of indexed symbols and other data.
10 //
11 // It writes sections:
12 //  - metadata such as version info
13 //  - a string table (which is compressed)
14 //  - lists of encoded symbols
15 //
16 // The format has a simple versioning scheme: the format version number is
17 // written in the file and non-current versions are rejected when reading.
18 //
19 // Human-readable YAML serialization is also supported, and recommended for
20 // debugging and experiments only.
21 //
22 //===----------------------------------------------------------------------===//
23 
24 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_INDEX_RIFF_H
25 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_INDEX_RIFF_H
26 
27 #include "Headers.h"
28 #include "Index.h"
29 #include "index/Symbol.h"
30 #include "clang/Tooling/CompilationDatabase.h"
31 #include "llvm/Support/Error.h"
32 
33 namespace clang {
34 namespace clangd {
35 
36 enum class IndexFileFormat {
37   RIFF, // Versioned binary format, suitable for production use.
38   YAML, // Human-readable format, suitable for experiments and debugging.
39 };
40 
41 // Holds the contents of an index file that was read.
42 struct IndexFileIn {
43   llvm::Optional<SymbolSlab> Symbols;
44   llvm::Optional<RefSlab> Refs;
45   llvm::Optional<RelationSlab> Relations;
46   // Keys are URIs of the source files.
47   llvm::Optional<IncludeGraph> Sources;
48   // This contains only the Directory and CommandLine.
49   llvm::Optional<tooling::CompileCommand> Cmd;
50 };
51 // Parse an index file. The input must be a RIFF or YAML file.
52 llvm::Expected<IndexFileIn> readIndexFile(llvm::StringRef);
53 
54 // Specifies the contents of an index file to be written.
55 struct IndexFileOut {
56   const SymbolSlab *Symbols = nullptr;
57   const RefSlab *Refs = nullptr;
58   const RelationSlab *Relations = nullptr;
59   // Keys are URIs of the source files.
60   const IncludeGraph *Sources = nullptr;
61   // TODO: Support serializing Dex posting lists.
62   IndexFileFormat Format = IndexFileFormat::RIFF;
63   const tooling::CompileCommand *Cmd = nullptr;
64 
65   IndexFileOut() = default;
IndexFileOutIndexFileOut66   IndexFileOut(const IndexFileIn &I)
67       : Symbols(I.Symbols ? I.Symbols.getPointer() : nullptr),
68         Refs(I.Refs ? I.Refs.getPointer() : nullptr),
69         Relations(I.Relations ? I.Relations.getPointer() : nullptr),
70         Sources(I.Sources ? I.Sources.getPointer() : nullptr),
71         Cmd(I.Cmd ? I.Cmd.getPointer() : nullptr) {}
72 };
73 // Serializes an index file.
74 llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, const IndexFileOut &O);
75 
76 // Convert a single symbol to YAML, a nice debug representation.
77 std::string toYAML(const Symbol &);
78 std::string toYAML(const std::pair<SymbolID, ArrayRef<Ref>> &);
79 std::string toYAML(const Relation &);
80 
81 // Build an in-memory static index from an index file.
82 // The size should be relatively small, so data can be managed in memory.
83 std::unique_ptr<SymbolIndex> loadIndex(llvm::StringRef Filename,
84                                        bool UseDex = true);
85 
86 } // namespace clangd
87 } // namespace clang
88 
89 #endif
90