clang  10.0.0svn
HeaderIncludes.cpp
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1 //===--- HeaderIncludes.cpp - Insert/Delete #includes --*- 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 
11 #include "clang/Lex/Lexer.h"
12 #include "llvm/ADT/Optional.h"
13 #include "llvm/Support/FormatVariadic.h"
14 
15 namespace clang {
16 namespace tooling {
17 namespace {
18 
19 LangOptions createLangOpts() {
20  LangOptions LangOpts;
21  LangOpts.CPlusPlus = 1;
22  LangOpts.CPlusPlus11 = 1;
23  LangOpts.CPlusPlus14 = 1;
24  LangOpts.LineComment = 1;
25  LangOpts.CXXOperatorNames = 1;
26  LangOpts.Bool = 1;
27  LangOpts.ObjC = 1;
28  LangOpts.MicrosoftExt = 1; // To get kw___try, kw___finally.
29  LangOpts.DeclSpecKeyword = 1; // To get __declspec.
30  LangOpts.WChar = 1; // To get wchar_t
31  return LangOpts;
32 }
33 
34 // Returns the offset after skipping a sequence of tokens, matched by \p
35 // GetOffsetAfterSequence, from the start of the code.
36 // \p GetOffsetAfterSequence should be a function that matches a sequence of
37 // tokens and returns an offset after the sequence.
38 unsigned getOffsetAfterTokenSequence(
39  StringRef FileName, StringRef Code, const IncludeStyle &Style,
40  llvm::function_ref<unsigned(const SourceManager &, Lexer &, Token &)>
41  GetOffsetAfterSequence) {
42  SourceManagerForFile VirtualSM(FileName, Code);
43  SourceManager &SM = VirtualSM.get();
44  Lexer Lex(SM.getMainFileID(), SM.getBuffer(SM.getMainFileID()), SM,
45  createLangOpts());
46  Token Tok;
47  // Get the first token.
48  Lex.LexFromRawLexer(Tok);
49  return GetOffsetAfterSequence(SM, Lex, Tok);
50 }
51 
52 // Check if a sequence of tokens is like "#<Name> <raw_identifier>". If it is,
53 // \p Tok will be the token after this directive; otherwise, it can be any token
54 // after the given \p Tok (including \p Tok). If \p RawIDName is provided, the
55 // (second) raw_identifier name is checked.
56 bool checkAndConsumeDirectiveWithName(
57  Lexer &Lex, StringRef Name, Token &Tok,
59  bool Matched = Tok.is(tok::hash) && !Lex.LexFromRawLexer(Tok) &&
60  Tok.is(tok::raw_identifier) &&
61  Tok.getRawIdentifier() == Name && !Lex.LexFromRawLexer(Tok) &&
62  Tok.is(tok::raw_identifier) &&
63  (!RawIDName || Tok.getRawIdentifier() == *RawIDName);
64  if (Matched)
65  Lex.LexFromRawLexer(Tok);
66  return Matched;
67 }
68 
69 void skipComments(Lexer &Lex, Token &Tok) {
70  while (Tok.is(tok::comment))
71  if (Lex.LexFromRawLexer(Tok))
72  return;
73 }
74 
75 // Returns the offset after header guard directives and any comments
76 // before/after header guards (e.g. #ifndef/#define pair, #pragma once). If no
77 // header guard is present in the code, this will return the offset after
78 // skipping all comments from the start of the code.
79 unsigned getOffsetAfterHeaderGuardsAndComments(StringRef FileName,
80  StringRef Code,
81  const IncludeStyle &Style) {
82  // \p Consume returns location after header guard or 0 if no header guard is
83  // found.
84  auto ConsumeHeaderGuardAndComment =
85  [&](std::function<unsigned(const SourceManager &SM, Lexer &Lex,
86  Token Tok)>
87  Consume) {
88  return getOffsetAfterTokenSequence(
89  FileName, Code, Style,
90  [&Consume](const SourceManager &SM, Lexer &Lex, Token Tok) {
91  skipComments(Lex, Tok);
92  unsigned InitialOffset = SM.getFileOffset(Tok.getLocation());
93  return std::max(InitialOffset, Consume(SM, Lex, Tok));
94  });
95  };
96  return std::max(
97  // #ifndef/#define
98  ConsumeHeaderGuardAndComment(
99  [](const SourceManager &SM, Lexer &Lex, Token Tok) -> unsigned {
100  if (checkAndConsumeDirectiveWithName(Lex, "ifndef", Tok)) {
101  skipComments(Lex, Tok);
102  if (checkAndConsumeDirectiveWithName(Lex, "define", Tok))
103  return SM.getFileOffset(Tok.getLocation());
104  }
105  return 0;
106  }),
107  // #pragma once
108  ConsumeHeaderGuardAndComment(
109  [](const SourceManager &SM, Lexer &Lex, Token Tok) -> unsigned {
110  if (checkAndConsumeDirectiveWithName(Lex, "pragma", Tok,
111  StringRef("once")))
112  return SM.getFileOffset(Tok.getLocation());
113  return 0;
114  }));
115 }
116 
117 // Check if a sequence of tokens is like
118 // "#include ("header.h" | <header.h>)".
119 // If it is, \p Tok will be the token after this directive; otherwise, it can be
120 // any token after the given \p Tok (including \p Tok).
121 bool checkAndConsumeInclusiveDirective(Lexer &Lex, Token &Tok) {
122  auto Matched = [&]() {
123  Lex.LexFromRawLexer(Tok);
124  return true;
125  };
126  if (Tok.is(tok::hash) && !Lex.LexFromRawLexer(Tok) &&
127  Tok.is(tok::raw_identifier) && Tok.getRawIdentifier() == "include") {
128  if (Lex.LexFromRawLexer(Tok))
129  return false;
130  if (Tok.is(tok::string_literal))
131  return Matched();
132  if (Tok.is(tok::less)) {
133  while (!Lex.LexFromRawLexer(Tok) && Tok.isNot(tok::greater)) {
134  }
135  if (Tok.is(tok::greater))
136  return Matched();
137  }
138  }
139  return false;
140 }
141 
142 // Returns the offset of the last #include directive after which a new
143 // #include can be inserted. This ignores #include's after the #include block(s)
144 // in the beginning of a file to avoid inserting headers into code sections
145 // where new #include's should not be added by default.
146 // These code sections include:
147 // - raw string literals (containing #include).
148 // - #if blocks.
149 // - Special #include's among declarations (e.g. functions).
150 //
151 // If no #include after which a new #include can be inserted, this returns the
152 // offset after skipping all comments from the start of the code.
153 // Inserting after an #include is not allowed if it comes after code that is not
154 // #include (e.g. pre-processing directive that is not #include, declarations).
155 unsigned getMaxHeaderInsertionOffset(StringRef FileName, StringRef Code,
156  const IncludeStyle &Style) {
157  return getOffsetAfterTokenSequence(
158  FileName, Code, Style,
159  [](const SourceManager &SM, Lexer &Lex, Token Tok) {
160  skipComments(Lex, Tok);
161  unsigned MaxOffset = SM.getFileOffset(Tok.getLocation());
162  while (checkAndConsumeInclusiveDirective(Lex, Tok))
163  MaxOffset = SM.getFileOffset(Tok.getLocation());
164  return MaxOffset;
165  });
166 }
167 
168 inline StringRef trimInclude(StringRef IncludeName) {
169  return IncludeName.trim("\"<>");
170 }
171 
172 const char IncludeRegexPattern[] =
173  R"(^[\t\ ]*#[\t\ ]*(import|include)[^"<]*(["<][^">]*[">]))";
174 
175 } // anonymous namespace
176 
178  StringRef FileName)
179  : Style(Style), FileName(FileName) {
180  FileStem = llvm::sys::path::stem(FileName);
181  for (const auto &Category : Style.IncludeCategories)
182  CategoryRegexs.emplace_back(Category.Regex, llvm::Regex::IgnoreCase);
183  IsMainFile = FileName.endswith(".c") || FileName.endswith(".cc") ||
184  FileName.endswith(".cpp") || FileName.endswith(".c++") ||
185  FileName.endswith(".cxx") || FileName.endswith(".m") ||
186  FileName.endswith(".mm");
187 }
188 
190  bool CheckMainHeader) const {
191  int Ret = INT_MAX;
192  for (unsigned i = 0, e = CategoryRegexs.size(); i != e; ++i)
193  if (CategoryRegexs[i].match(IncludeName)) {
194  Ret = Style.IncludeCategories[i].Priority;
195  break;
196  }
197  if (CheckMainHeader && IsMainFile && Ret > 0 && isMainHeader(IncludeName))
198  Ret = 0;
199  return Ret;
200 }
201 
202 bool IncludeCategoryManager::isMainHeader(StringRef IncludeName) const {
203  if (!IncludeName.startswith("\""))
204  return false;
205  StringRef HeaderStem =
206  llvm::sys::path::stem(IncludeName.drop_front(1).drop_back(1));
207  if (FileStem.startswith(HeaderStem) ||
208  FileStem.startswith_lower(HeaderStem)) {
209  llvm::Regex MainIncludeRegex(HeaderStem.str() + Style.IncludeIsMainRegex,
210  llvm::Regex::IgnoreCase);
211  if (MainIncludeRegex.match(FileStem))
212  return true;
213  }
214  return false;
215 }
216 
217 HeaderIncludes::HeaderIncludes(StringRef FileName, StringRef Code,
218  const IncludeStyle &Style)
219  : FileName(FileName), Code(Code), FirstIncludeOffset(-1),
220  MinInsertOffset(
221  getOffsetAfterHeaderGuardsAndComments(FileName, Code, Style)),
222  MaxInsertOffset(MinInsertOffset +
223  getMaxHeaderInsertionOffset(
224  FileName, Code.drop_front(MinInsertOffset), Style)),
225  Categories(Style, FileName),
226  IncludeRegex(llvm::Regex(IncludeRegexPattern)) {
227  // Add 0 for main header and INT_MAX for headers that are not in any
228  // category.
229  Priorities = {0, INT_MAX};
230  for (const auto &Category : Style.IncludeCategories)
231  Priorities.insert(Category.Priority);
233  Code.drop_front(MinInsertOffset).split(Lines, "\n");
234 
235  unsigned Offset = MinInsertOffset;
236  unsigned NextLineOffset;
238  for (auto Line : Lines) {
239  NextLineOffset = std::min(Code.size(), Offset + Line.size() + 1);
240  if (IncludeRegex.match(Line, &Matches)) {
241  // If this is the last line without trailing newline, we need to make
242  // sure we don't delete across the file boundary.
243  addExistingInclude(
244  Include(Matches[2],
246  Offset, std::min(Line.size() + 1, Code.size() - Offset))),
247  NextLineOffset);
248  }
249  Offset = NextLineOffset;
250  }
251 
252  // Populate CategoryEndOfssets:
253  // - Ensure that CategoryEndOffset[Highest] is always populated.
254  // - If CategoryEndOffset[Priority] isn't set, use the next higher value
255  // that is set, up to CategoryEndOffset[Highest].
256  auto Highest = Priorities.begin();
257  if (CategoryEndOffsets.find(*Highest) == CategoryEndOffsets.end()) {
258  if (FirstIncludeOffset >= 0)
259  CategoryEndOffsets[*Highest] = FirstIncludeOffset;
260  else
261  CategoryEndOffsets[*Highest] = MinInsertOffset;
262  }
263  // By this point, CategoryEndOffset[Highest] is always set appropriately:
264  // - to an appropriate location before/after existing #includes, or
265  // - to right after the header guard, or
266  // - to the beginning of the file.
267  for (auto I = ++Priorities.begin(), E = Priorities.end(); I != E; ++I)
268  if (CategoryEndOffsets.find(*I) == CategoryEndOffsets.end())
269  CategoryEndOffsets[*I] = CategoryEndOffsets[*std::prev(I)];
270 }
271 
272 // \p Offset: the start of the line following this include directive.
273 void HeaderIncludes::addExistingInclude(Include IncludeToAdd,
274  unsigned NextLineOffset) {
275  auto Iter =
276  ExistingIncludes.try_emplace(trimInclude(IncludeToAdd.Name)).first;
277  Iter->second.push_back(std::move(IncludeToAdd));
278  auto &CurInclude = Iter->second.back();
279  // The header name with quotes or angle brackets.
280  // Only record the offset of current #include if we can insert after it.
281  if (CurInclude.R.getOffset() <= MaxInsertOffset) {
282  int Priority = Categories.getIncludePriority(
283  CurInclude.Name, /*CheckMainHeader=*/FirstIncludeOffset < 0);
284  CategoryEndOffsets[Priority] = NextLineOffset;
285  IncludesByPriority[Priority].push_back(&CurInclude);
286  if (FirstIncludeOffset < 0)
287  FirstIncludeOffset = CurInclude.R.getOffset();
288  }
289 }
290 
292 HeaderIncludes::insert(llvm::StringRef IncludeName, bool IsAngled) const {
293  assert(IncludeName == trimInclude(IncludeName));
294  // If a <header> ("header") already exists in code, "header" (<header>) with
295  // different quotation will still be inserted.
296  // FIXME: figure out if this is the best behavior.
297  auto It = ExistingIncludes.find(IncludeName);
298  if (It != ExistingIncludes.end())
299  for (const auto &Inc : It->second)
300  if ((IsAngled && StringRef(Inc.Name).startswith("<")) ||
301  (!IsAngled && StringRef(Inc.Name).startswith("\"")))
302  return llvm::None;
303  std::string Quoted =
304  llvm::formatv(IsAngled ? "<{0}>" : "\"{0}\"", IncludeName);
305  StringRef QuotedName = Quoted;
306  int Priority = Categories.getIncludePriority(
307  QuotedName, /*CheckMainHeader=*/FirstIncludeOffset < 0);
308  auto CatOffset = CategoryEndOffsets.find(Priority);
309  assert(CatOffset != CategoryEndOffsets.end());
310  unsigned InsertOffset = CatOffset->second; // Fall back offset
311  auto Iter = IncludesByPriority.find(Priority);
312  if (Iter != IncludesByPriority.end()) {
313  for (const auto *Inc : Iter->second) {
314  if (QuotedName < Inc->Name) {
315  InsertOffset = Inc->R.getOffset();
316  break;
317  }
318  }
319  }
320  assert(InsertOffset <= Code.size());
321  std::string NewInclude = llvm::formatv("#include {0}\n", QuotedName);
322  // When inserting headers at end of the code, also append '\n' to the code
323  // if it does not end with '\n'.
324  // FIXME: when inserting multiple #includes at the end of code, only one
325  // newline should be added.
326  if (InsertOffset == Code.size() && (!Code.empty() && Code.back() != '\n'))
327  NewInclude = "\n" + NewInclude;
328  return tooling::Replacement(FileName, InsertOffset, 0, NewInclude);
329 }
330 
331 tooling::Replacements HeaderIncludes::remove(llvm::StringRef IncludeName,
332  bool IsAngled) const {
333  assert(IncludeName == trimInclude(IncludeName));
334  tooling::Replacements Result;
335  auto Iter = ExistingIncludes.find(IncludeName);
336  if (Iter == ExistingIncludes.end())
337  return Result;
338  for (const auto &Inc : Iter->second) {
339  if ((IsAngled && StringRef(Inc.Name).startswith("\"")) ||
340  (!IsAngled && StringRef(Inc.Name).startswith("<")))
341  continue;
342  llvm::Error Err = Result.add(tooling::Replacement(
343  FileName, Inc.R.getOffset(), Inc.R.getLength(), ""));
344  if (Err) {
345  auto ErrMsg = "Unexpected conflicts in #include deletions: " +
346  llvm::toString(std::move(Err));
347  llvm_unreachable(ErrMsg.c_str());
348  }
349  }
350  return Result;
351 }
352 
353 
354 } // namespace tooling
355 } // namespace clang
Specialize PointerLikeTypeTraits to allow LazyGenerationalUpdatePtr to be placed into a PointerUnion...
Definition: Dominators.h:30
Defines the SourceManager interface.
llvm::Error add(const Replacement &R)
Adds a new replacement R to the current set of replacements.
std::vector< IncludeCategory > IncludeCategories
Regular expressions denoting the different #include categories used for ordering #includes.
Definition: IncludeStyle.h:98
Maintains a set of replacements that are conflict-free.
Definition: Replacement.h:209
static std::string toString(const clang::SanitizerSet &Sanitizers)
Produce a string containing comma-separated names of sanitizers in Sanitizers set.
int Category
Definition: Format.cpp:1729
__DEVICE__ int max(int __a, int __b)
HeaderIncludes(llvm::StringRef FileName, llvm::StringRef Code, const IncludeStyle &Style)
const FormatToken & Tok
SmallVector< BoundNodes, 1 > match(MatcherT Matcher, const NodeT &Node, ASTContext &Context)
Returns the results of matching Matcher on Node.
A text replacement.
Definition: Replacement.h:83
A source range independent of the SourceManager.
Definition: Replacement.h:44
unsigned Offset
Definition: Format.cpp:1728
const AnnotatedLine * Line
llvm::Optional< tooling::Replacement > insert(llvm::StringRef Header, bool IsAngled) const
Inserts an #include directive of Header into the code.
const SourceManager & SM
Definition: Format.cpp:1586
Style for sorting and grouping C++ #include directives.
Definition: IncludeStyle.h:20
Dataflow Directional Tag Classes.
IncludeCategoryManager(const IncludeStyle &Style, StringRef FileName)
int getIncludePriority(StringRef IncludeName, bool CheckMainHeader) const
Returns the priority of the category which IncludeName belongs to.
#define INT_MAX
Definition: limits.h:46
__DEVICE__ int min(int __a, int __b)
A node that&#39;s not selected.
tooling::Replacements remove(llvm::StringRef Header, bool IsAngled) const
Removes all existing #includes of Header quoted with <> if IsAngled is true or "" if IsAngled is fals...
const FormatStyle & Style