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
13namespace clang {
14namespace comments {
15
16#include "clang/AST/CommentCommandInfo.inc"
17
18CommandTraits::CommandTraits(llvm::BumpPtrAllocator &Allocator,
19                             const CommentOptions &CommentOptions) :
20    NextID(llvm::array_lengthof(Commands)), Allocator(Allocator) {
21  registerCommentOptions(CommentOptions);
22}
23
24void 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
34const CommandInfo *CommandTraits::getCommandInfoOrNULL(StringRef Name) const {
35  if (const CommandInfo *Info = getBuiltinCommandInfo(Name))
36    return Info;
37  return getRegisteredCommandInfo(Name);
38}
39
40const CommandInfo *CommandTraits::getCommandInfo(unsigned CommandID) const {
41  if (const CommandInfo *Info = getBuiltinCommandInfo(CommandID))
42    return Info;
43  return getRegisteredCommandInfo(CommandID);
44}
45
46static void
47HelperTypoCorrectCommandInfo(SmallVectorImpl<const CommandInfo *> &BestCommand,
48                             StringRef Typo, const CommandInfo *Command) {
49  const unsigned MaxEditDistance = 1;
50  unsigned BestEditDistance = MaxEditDistance + 1;
51  StringRef Name = Command->Name;
52
53  unsigned MinPossibleEditDistance = abs((int)Name.size() - (int)Typo.size());
54  if (MinPossibleEditDistance > 0 &&
55      Typo.size() / MinPossibleEditDistance < 1)
56    return;
57  unsigned EditDistance = Typo.edit_distance(Name, true, MaxEditDistance);
58  if (EditDistance > MaxEditDistance)
59    return;
60  if (EditDistance == BestEditDistance)
61    BestCommand.push_back(Command);
62  else if (EditDistance < BestEditDistance) {
63    BestCommand.clear();
64    BestCommand.push_back(Command);
65    BestEditDistance = EditDistance;
66  }
67}
68
69const CommandInfo *
70CommandTraits::getTypoCorrectCommandInfo(StringRef Typo) const {
71  // single character command impostures, such as \t or \n must not go
72  // through the fixit logic.
73  if (Typo.size() <= 1)
74    return NULL;
75
76  SmallVector<const CommandInfo *, 2> BestCommand;
77
78  const int NumOfCommands = llvm::array_lengthof(Commands);
79  for (int i = 0; i < NumOfCommands; i++)
80    HelperTypoCorrectCommandInfo(BestCommand, Typo, &Commands[i]);
81
82  for (unsigned i = 0, e = RegisteredCommands.size(); i != e; ++i)
83    if (!RegisteredCommands[i]->IsUnknownCommand)
84      HelperTypoCorrectCommandInfo(BestCommand, Typo, RegisteredCommands[i]);
85
86  return (BestCommand.size() != 1) ? NULL : BestCommand[0];
87}
88
89CommandInfo *CommandTraits::createCommandInfoWithName(StringRef CommandName) {
90  char *Name = Allocator.Allocate<char>(CommandName.size() + 1);
91  memcpy(Name, CommandName.data(), CommandName.size());
92  Name[CommandName.size()] = '\0';
93
94  // Value-initialize (=zero-initialize in this case) a new CommandInfo.
95  CommandInfo *Info = new (Allocator) CommandInfo();
96  Info->Name = Name;
97  Info->ID = NextID++;
98
99  RegisteredCommands.push_back(Info);
100
101  return Info;
102}
103
104const CommandInfo *CommandTraits::registerUnknownCommand(
105                                                  StringRef CommandName) {
106  CommandInfo *Info = createCommandInfoWithName(CommandName);
107  Info->IsUnknownCommand = true;
108  return Info;
109}
110
111const CommandInfo *CommandTraits::registerBlockCommand(StringRef CommandName) {
112  CommandInfo *Info = createCommandInfoWithName(CommandName);
113  Info->IsBlockCommand = true;
114  return Info;
115}
116
117const CommandInfo *CommandTraits::getBuiltinCommandInfo(
118                                                  unsigned CommandID) {
119  if (CommandID < llvm::array_lengthof(Commands))
120    return &Commands[CommandID];
121  return NULL;
122}
123
124const CommandInfo *CommandTraits::getRegisteredCommandInfo(
125                                                  StringRef Name) const {
126  for (unsigned i = 0, e = RegisteredCommands.size(); i != e; ++i) {
127    if (RegisteredCommands[i]->Name == Name)
128      return RegisteredCommands[i];
129  }
130  return NULL;
131}
132
133const CommandInfo *CommandTraits::getRegisteredCommandInfo(
134                                                  unsigned CommandID) const {
135  return RegisteredCommands[CommandID - llvm::array_lengthof(Commands)];
136}
137
138} // end namespace comments
139} // end namespace clang
140
141