clang-tools  8.0.0
URI.h
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1 //===--- URI.h - File URIs with schemes --------------------------*- 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 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_PATHURI_H
11 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_PATHURI_H
12 
13 #include "llvm/ADT/StringRef.h"
14 #include "llvm/Support/Error.h"
15 #include "llvm/Support/Registry.h"
16 
17 namespace clang {
18 namespace clangd {
19 
20 /// A URI describes the location of a source file.
21 /// In the simplest case, this is a "file" URI that directly encodes the
22 /// absolute path to a file. More abstract cases are possible: a shared index
23 /// service might expose repo:// URIs that are relative to the source control
24 /// root.
25 ///
26 /// Clangd handles URIs of the form <scheme>:[//<authority>]<body>. It doesn't
27 /// further split the authority or body into constituent parts (e.g. query
28 /// strings is included in the body).
29 class URI {
30 public:
31  URI(llvm::StringRef Scheme, llvm::StringRef Authority, llvm::StringRef Body);
32 
33  /// Returns decoded scheme e.g. "https"
34  llvm::StringRef scheme() const { return Scheme; }
35  /// Returns decoded authority e.g. "reviews.lvm.org"
36  llvm::StringRef authority() const { return Authority; }
37  /// Returns decoded body e.g. "/D41946"
38  llvm::StringRef body() const { return Body; }
39 
40  /// Returns a string URI with all components percent-encoded.
41  std::string toString() const;
42 
43  /// Creates a URI for a file in the given scheme. \p Scheme must be
44  /// registered. The URI is percent-encoded.
45  static llvm::Expected<URI> create(llvm::StringRef AbsolutePath,
46  llvm::StringRef Scheme);
47 
48  // Similar to above except this picks a registered scheme that works. If none
49  // works, this falls back to "file" scheme.
50  static URI create(llvm::StringRef AbsolutePath);
51 
52  /// This creates a file:// URI for \p AbsolutePath. The path must be absolute.
53  static URI createFile(llvm::StringRef AbsolutePath);
54 
55  /// Parse a URI string "<scheme>:[//<authority>/]<path>". Percent-encoded
56  /// characters in the URI will be decoded.
57  static llvm::Expected<URI> parse(llvm::StringRef Uri);
58 
59  /// Resolves the absolute path of \p U. If there is no matching scheme, or the
60  /// URI is invalid in the scheme, this returns an error.
61  ///
62  /// \p HintPath A related path, such as the current file or working directory,
63  /// which can help disambiguate when the same file exists in many workspaces.
64  static llvm::Expected<std::string> resolve(const URI &U,
65  llvm::StringRef HintPath = "");
66 
67  /// Resolves \p AbsPath into a canonical path of its URI, by converting
68  /// \p AbsPath to URI and resolving the URI to get th canonical path.
69  /// This ensures that paths with the same URI are resolved into consistent
70  /// file path.
71  static llvm::Expected<std::string> resolvePath(llvm::StringRef AbsPath,
72  llvm::StringRef HintPath = "");
73 
74  /// Gets the preferred spelling of this file for #include, if there is one,
75  /// e.g. <system_header.h>, "path/to/x.h".
76  ///
77  /// This allows URI schemas to provide their customized include paths.
78  ///
79  /// Returns an empty string if normal include-shortening based on the absolute
80  /// path should be used.
81  /// Fails if the URI is not valid in the schema.
82  static llvm::Expected<std::string> includeSpelling(const URI &U);
83 
84  friend bool operator==(const URI &LHS, const URI &RHS) {
85  return std::tie(LHS.Scheme, LHS.Authority, LHS.Body) ==
86  std::tie(RHS.Scheme, RHS.Authority, RHS.Body);
87  }
88 
89  friend bool operator<(const URI &LHS, const URI &RHS) {
90  return std::tie(LHS.Scheme, LHS.Authority, LHS.Body) <
91  std::tie(RHS.Scheme, RHS.Authority, RHS.Body);
92  }
93 
94 private:
95  URI() = default;
96 
97  std::string Scheme;
98  std::string Authority;
99  std::string Body;
100 };
101 
102 /// URIScheme is an extension point for teaching clangd to recognize a custom
103 /// URI scheme. This is expected to be implemented and exposed via the
104 /// URISchemeRegistry.
105 class URIScheme {
106 public:
107  virtual ~URIScheme() = default;
108 
109  /// Returns the absolute path of the file corresponding to the URI
110  /// authority+body in the file system. See URI::resolve for semantics of
111  /// \p HintPath.
112  virtual llvm::Expected<std::string>
113  getAbsolutePath(llvm::StringRef Authority, llvm::StringRef Body,
114  llvm::StringRef HintPath) const = 0;
115 
116  virtual llvm::Expected<URI>
117  uriFromAbsolutePath(llvm::StringRef AbsolutePath) const = 0;
118 
119  /// Returns the include path of the file (e.g. <path>, "path"), which can be
120  /// #included directly. See URI::includeSpelling for details.
121  virtual llvm::Expected<std::string> getIncludeSpelling(const URI &U) const {
122  return ""; // no customized include path for this scheme.
123  }
124 };
125 
126 /// By default, a "file" scheme is supported where URI paths are always absolute
127 /// in the file system.
128 typedef llvm::Registry<URIScheme> URISchemeRegistry;
129 
130 } // namespace clangd
131 } // namespace clang
132 
133 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_PATHURI_H
friend bool operator==(const URI &LHS, const URI &RHS)
Definition: URI.h:84
URIScheme is an extension point for teaching clangd to recognize a custom URI scheme.
Definition: URI.h:105
virtual llvm::Expected< std::string > getIncludeSpelling(const URI &U) const
Returns the include path of the file (e.g.
Definition: URI.h:121
llvm::StringRef authority() const
Returns decoded authority e.g. "reviews.lvm.org".
Definition: URI.h:36
static URI createFile(llvm::StringRef AbsolutePath)
This creates a file:// URI for AbsolutePath. The path must be absolute.
Definition: URI.cpp:217
llvm::Registry< URIScheme > URISchemeRegistry
By default, a "file" scheme is supported where URI paths are always absolute in the file system...
Definition: URI.h:128
llvm::StringRef scheme() const
Returns decoded scheme e.g. "https".
Definition: URI.h:34
static llvm::Expected< std::string > resolvePath(llvm::StringRef AbsPath, llvm::StringRef HintPath="")
Resolves AbsPath into a canonical path of its URI, by converting AbsPath to URI and resolving the URI...
Definition: URI.cpp:232
llvm::StringRef body() const
Returns decoded body e.g. "/D41946".
Definition: URI.h:38
static llvm::Expected< URI > create(llvm::StringRef AbsolutePath, llvm::StringRef Scheme)
Creates a URI for a file in the given scheme.
Definition: URI.cpp:188
friend bool operator<(const URI &LHS, const URI &RHS)
Definition: URI.h:89
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
A URI describes the location of a source file.
Definition: URI.h:29
static llvm::Expected< std::string > resolve(const URI &U, llvm::StringRef HintPath="")
Resolves the absolute path of U.
Definition: URI.cpp:224
static llvm::Expected< std::string > includeSpelling(const URI &U)
Gets the preferred spelling of this file for #include, if there is one, e.g.
Definition: URI.cpp:252
static llvm::Expected< URI > parse(llvm::StringRef Uri)
Parse a URI string "<scheme>:[//<authority>/]<path>".
Definition: URI.cpp:166
std::string toString() const
Returns a string URI with all components percent-encoded.
Definition: URI.cpp:151