1 //===--- CommentCommandTraits.cpp - Comment command properties --*- 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 #include "clang/AST/CommentCommandTraits.h"
11 #include "llvm/ADT/STLExtras.h"
12
13 namespace clang {
14 namespace comments {
15
16 #include "clang/AST/CommentCommandInfo.inc"
17
CommandTraits(llvm::BumpPtrAllocator & Allocator,const CommentOptions & CommentOptions)18 CommandTraits::CommandTraits(llvm::BumpPtrAllocator &Allocator,
19 const CommentOptions &CommentOptions) :
20 NextID(llvm::array_lengthof(Commands)), Allocator(Allocator) {
21 registerCommentOptions(CommentOptions);
22 }
23
registerCommentOptions(const CommentOptions & CommentOptions)24 void CommandTraits::registerCommentOptions(
25 const CommentOptions &CommentOptions) {
26 for (CommentOptions::BlockCommandNamesTy::const_iterator
27 I = CommentOptions.BlockCommandNames.begin(),
28 E = CommentOptions.BlockCommandNames.end();
29 I != E; I++) {
30 registerBlockCommand(*I);
31 }
32 }
33
getCommandInfoOrNULL(StringRef Name) const34 const CommandInfo *CommandTraits::getCommandInfoOrNULL(StringRef Name) const {
35 if (const CommandInfo *Info = getBuiltinCommandInfo(Name))
36 return Info;
37 return getRegisteredCommandInfo(Name);
38 }
39
getCommandInfo(unsigned CommandID) const40 const CommandInfo *CommandTraits::getCommandInfo(unsigned CommandID) const {
41 if (const CommandInfo *Info = getBuiltinCommandInfo(CommandID))
42 return Info;
43 return getRegisteredCommandInfo(CommandID);
44 }
45
46 const CommandInfo *
getTypoCorrectCommandInfo(StringRef Typo) const47 CommandTraits::getTypoCorrectCommandInfo(StringRef Typo) const {
48 // Single-character command impostures, such as \t or \n, should not go
49 // through the fixit logic.
50 if (Typo.size() <= 1)
51 return nullptr;
52
53 // The maximum edit distance we're prepared to accept.
54 const unsigned MaxEditDistance = 1;
55
56 unsigned BestEditDistance = MaxEditDistance;
57 SmallVector<const CommandInfo *, 2> BestCommand;
58
59 auto ConsiderCorrection = [&](const CommandInfo *Command) {
60 StringRef Name = Command->Name;
61
62 unsigned MinPossibleEditDistance = abs((int)Name.size() - (int)Typo.size());
63 if (MinPossibleEditDistance <= BestEditDistance) {
64 unsigned EditDistance = Typo.edit_distance(Name, true, BestEditDistance);
65 if (EditDistance < BestEditDistance) {
66 BestEditDistance = EditDistance;
67 BestCommand.clear();
68 }
69 if (EditDistance == BestEditDistance)
70 BestCommand.push_back(Command);
71 }
72 };
73
74 for (const auto &Command : Commands)
75 ConsiderCorrection(&Command);
76
77 for (const auto *Command : RegisteredCommands)
78 if (!Command->IsUnknownCommand)
79 ConsiderCorrection(Command);
80
81 return BestCommand.size() == 1 ? BestCommand[0] : nullptr;
82 }
83
createCommandInfoWithName(StringRef CommandName)84 CommandInfo *CommandTraits::createCommandInfoWithName(StringRef CommandName) {
85 char *Name = Allocator.Allocate<char>(CommandName.size() + 1);
86 memcpy(Name, CommandName.data(), CommandName.size());
87 Name[CommandName.size()] = '\0';
88
89 // Value-initialize (=zero-initialize in this case) a new CommandInfo.
90 CommandInfo *Info = new (Allocator) CommandInfo();
91 Info->Name = Name;
92 // We only have a limited number of bits to encode command IDs in the
93 // CommandInfo structure, so the ID numbers can potentially wrap around.
94 assert((NextID < (1 << CommandInfo::NumCommandIDBits))
95 && "Too many commands. We have limited bits for the command ID.");
96 Info->ID = NextID++;
97
98 RegisteredCommands.push_back(Info);
99
100 return Info;
101 }
102
registerUnknownCommand(StringRef CommandName)103 const CommandInfo *CommandTraits::registerUnknownCommand(
104 StringRef CommandName) {
105 CommandInfo *Info = createCommandInfoWithName(CommandName);
106 Info->IsUnknownCommand = true;
107 return Info;
108 }
109
registerBlockCommand(StringRef CommandName)110 const CommandInfo *CommandTraits::registerBlockCommand(StringRef CommandName) {
111 CommandInfo *Info = createCommandInfoWithName(CommandName);
112 Info->IsBlockCommand = true;
113 return Info;
114 }
115
getBuiltinCommandInfo(unsigned CommandID)116 const CommandInfo *CommandTraits::getBuiltinCommandInfo(
117 unsigned CommandID) {
118 if (CommandID < llvm::array_lengthof(Commands))
119 return &Commands[CommandID];
120 return nullptr;
121 }
122
getRegisteredCommandInfo(StringRef Name) const123 const CommandInfo *CommandTraits::getRegisteredCommandInfo(
124 StringRef Name) const {
125 for (unsigned i = 0, e = RegisteredCommands.size(); i != e; ++i) {
126 if (RegisteredCommands[i]->Name == Name)
127 return RegisteredCommands[i];
128 }
129 return nullptr;
130 }
131
getRegisteredCommandInfo(unsigned CommandID) const132 const CommandInfo *CommandTraits::getRegisteredCommandInfo(
133 unsigned CommandID) const {
134 return RegisteredCommands[CommandID - llvm::array_lengthof(Commands)];
135 }
136
137 } // end namespace comments
138 } // end namespace clang
139
140