1 //===--- CommentCommandTraits.cpp - Comment command properties --*- 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 #include "clang/AST/CommentCommandTraits.h" 10 #include "llvm/ADT/STLExtras.h" 11 12 namespace clang { 13 namespace comments { 14 15 #include "clang/AST/CommentCommandInfo.inc" 16 17 CommandTraits::CommandTraits(llvm::BumpPtrAllocator &Allocator, 18 const CommentOptions &CommentOptions) : 19 NextID(llvm::array_lengthof(Commands)), Allocator(Allocator) { 20 registerCommentOptions(CommentOptions); 21 } 22 23 void CommandTraits::registerCommentOptions( 24 const CommentOptions &CommentOptions) { 25 for (CommentOptions::BlockCommandNamesTy::const_iterator 26 I = CommentOptions.BlockCommandNames.begin(), 27 E = CommentOptions.BlockCommandNames.end(); 28 I != E; I++) { 29 registerBlockCommand(*I); 30 } 31 } 32 33 const CommandInfo *CommandTraits::getCommandInfoOrNULL(StringRef Name) const { 34 if (const CommandInfo *Info = getBuiltinCommandInfo(Name)) 35 return Info; 36 return getRegisteredCommandInfo(Name); 37 } 38 39 const CommandInfo *CommandTraits::getCommandInfo(unsigned CommandID) const { 40 if (const CommandInfo *Info = getBuiltinCommandInfo(CommandID)) 41 return Info; 42 return getRegisteredCommandInfo(CommandID); 43 } 44 45 const CommandInfo * 46 CommandTraits::getTypoCorrectCommandInfo(StringRef Typo) const { 47 // Single-character command impostures, such as \t or \n, should not go 48 // through the fixit logic. 49 if (Typo.size() <= 1) 50 return nullptr; 51 52 // The maximum edit distance we're prepared to accept. 53 const unsigned MaxEditDistance = 1; 54 55 unsigned BestEditDistance = MaxEditDistance; 56 SmallVector<const CommandInfo *, 2> BestCommand; 57 58 auto ConsiderCorrection = [&](const CommandInfo *Command) { 59 StringRef Name = Command->Name; 60 61 unsigned MinPossibleEditDistance = abs((int)Name.size() - (int)Typo.size()); 62 if (MinPossibleEditDistance <= BestEditDistance) { 63 unsigned EditDistance = Typo.edit_distance(Name, true, BestEditDistance); 64 if (EditDistance < BestEditDistance) { 65 BestEditDistance = EditDistance; 66 BestCommand.clear(); 67 } 68 if (EditDistance == BestEditDistance) 69 BestCommand.push_back(Command); 70 } 71 }; 72 73 for (const auto &Command : Commands) 74 ConsiderCorrection(&Command); 75 76 for (const auto *Command : RegisteredCommands) 77 if (!Command->IsUnknownCommand) 78 ConsiderCorrection(Command); 79 80 return BestCommand.size() == 1 ? BestCommand[0] : nullptr; 81 } 82 83 CommandInfo *CommandTraits::createCommandInfoWithName(StringRef CommandName) { 84 char *Name = Allocator.Allocate<char>(CommandName.size() + 1); 85 memcpy(Name, CommandName.data(), CommandName.size()); 86 Name[CommandName.size()] = '\0'; 87 88 // Value-initialize (=zero-initialize in this case) a new CommandInfo. 89 CommandInfo *Info = new (Allocator) CommandInfo(); 90 Info->Name = Name; 91 // We only have a limited number of bits to encode command IDs in the 92 // CommandInfo structure, so the ID numbers can potentially wrap around. 93 assert((NextID < (1 << CommandInfo::NumCommandIDBits)) 94 && "Too many commands. We have limited bits for the command ID."); 95 Info->ID = NextID++; 96 97 RegisteredCommands.push_back(Info); 98 99 return Info; 100 } 101 102 const CommandInfo *CommandTraits::registerUnknownCommand( 103 StringRef CommandName) { 104 CommandInfo *Info = createCommandInfoWithName(CommandName); 105 Info->IsUnknownCommand = true; 106 return Info; 107 } 108 109 const CommandInfo *CommandTraits::registerBlockCommand(StringRef CommandName) { 110 CommandInfo *Info = createCommandInfoWithName(CommandName); 111 Info->IsBlockCommand = true; 112 return Info; 113 } 114 115 const CommandInfo *CommandTraits::getBuiltinCommandInfo( 116 unsigned CommandID) { 117 if (CommandID < llvm::array_lengthof(Commands)) 118 return &Commands[CommandID]; 119 return nullptr; 120 } 121 122 const CommandInfo *CommandTraits::getRegisteredCommandInfo( 123 StringRef Name) const { 124 for (unsigned i = 0, e = RegisteredCommands.size(); i != e; ++i) { 125 if (RegisteredCommands[i]->Name == Name) 126 return RegisteredCommands[i]; 127 } 128 return nullptr; 129 } 130 131 const CommandInfo *CommandTraits::getRegisteredCommandInfo( 132 unsigned CommandID) const { 133 return RegisteredCommands[CommandID - llvm::array_lengthof(Commands)]; 134 } 135 136 } // end namespace comments 137 } // end namespace clang 138 139