1 //===--- HeaderIncludes.cpp - Insert/Delete #includes --*- C++ -*----------===//
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
7 //===----------------------------------------------------------------------===//
9 #include "clang/Tooling/Inclusions/HeaderIncludes.h"
10 #include "clang/Basic/SourceManager.h"
11 #include "clang/Lex/Lexer.h"
12 #include "llvm/ADT/Optional.h"
13 #include "llvm/Support/FormatVariadic.h"
19 LangOptions createLangOpts() {
21 LangOpts.CPlusPlus = 1;
22 LangOpts.CPlusPlus11 = 1;
23 LangOpts.CPlusPlus14 = 1;
24 LangOpts.LineComment = 1;
25 LangOpts.CXXOperatorNames = 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
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,
47 // Get the first token.
48 Lex.LexFromRawLexer(Tok);
49 return GetOffsetAfterSequence(SM, Lex, Tok);
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,
58 llvm::Optional<StringRef> RawIDName = llvm::None) {
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);
65 Lex.LexFromRawLexer(Tok);
69 void skipComments(Lexer &Lex, Token &Tok) {
70 while (Tok.is(tok::comment))
71 if (Lex.LexFromRawLexer(Tok))
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,
81 const IncludeStyle &Style) {
82 // \p Consume returns location after header guard or 0 if no header guard is
84 auto ConsumeHeaderGuardAndComment =
85 [&](std::function<unsigned(const SourceManager &SM, Lexer &Lex,
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));
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());
108 ConsumeHeaderGuardAndComment(
109 [](const SourceManager &SM, Lexer &Lex, Token Tok) -> unsigned {
110 if (checkAndConsumeDirectiveWithName(Lex, "pragma", Tok,
112 return SM.getFileOffset(Tok.getLocation());
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);
126 if (Tok.is(tok::hash) && !Lex.LexFromRawLexer(Tok) &&
127 Tok.is(tok::raw_identifier) && Tok.getRawIdentifier() == "include") {
128 if (Lex.LexFromRawLexer(Tok))
130 if (Tok.is(tok::string_literal))
132 if (Tok.is(tok::less)) {
133 while (!Lex.LexFromRawLexer(Tok) && Tok.isNot(tok::greater)) {
135 if (Tok.is(tok::greater))
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).
149 // - Special #include's among declarations (e.g. functions).
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());
168 inline StringRef trimInclude(StringRef IncludeName) {
169 return IncludeName.trim("\"<>");
172 const char IncludeRegexPattern[] =
173 R"(^[\t\ ]*#[\t\ ]*(import|include)[^"<]*(["<][^">]*[">]))";
175 } // anonymous namespace
177 IncludeCategoryManager::IncludeCategoryManager(const IncludeStyle &Style,
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");
189 int IncludeCategoryManager::getIncludePriority(StringRef IncludeName,
190 bool CheckMainHeader) const {
192 for (unsigned i = 0, e = CategoryRegexs.size(); i != e; ++i)
193 if (CategoryRegexs[i].match(IncludeName)) {
194 Ret = Style.IncludeCategories[i].Priority;
197 if (CheckMainHeader && IsMainFile && Ret > 0 && isMainHeader(IncludeName))
202 bool IncludeCategoryManager::isMainHeader(StringRef IncludeName) const {
203 if (!IncludeName.startswith("\""))
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))
217 HeaderIncludes::HeaderIncludes(StringRef FileName, StringRef Code,
218 const IncludeStyle &Style)
219 : FileName(FileName), Code(Code), FirstIncludeOffset(-1),
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
229 Priorities = {0, INT_MAX};
230 for (const auto &Category : Style.IncludeCategories)
231 Priorities.insert(Category.Priority);
232 SmallVector<StringRef, 32> Lines;
233 Code.drop_front(MinInsertOffset).split(Lines, "\n");
235 unsigned Offset = MinInsertOffset;
236 unsigned NextLineOffset;
237 SmallVector<StringRef, 4> Matches;
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.
246 Offset, std::min(Line.size() + 1, Code.size() - Offset))),
249 Offset = NextLineOffset;
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;
261 CategoryEndOffsets[*Highest] = MinInsertOffset;
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)];
272 // \p Offset: the start of the line following this include directive.
273 void HeaderIncludes::addExistingInclude(Include IncludeToAdd,
274 unsigned NextLineOffset) {
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();
291 llvm::Optional<tooling::Replacement>
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("\"")))
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();
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);
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())
338 for (const auto &Inc : Iter->second) {
339 if ((IsAngled && StringRef(Inc.Name).startswith("\"")) ||
340 (!IsAngled && StringRef(Inc.Name).startswith("<")))
342 llvm::Error Err = Result.add(tooling::Replacement(
343 FileName, Inc.R.getOffset(), Inc.R.getLength(), ""));
345 auto ErrMsg = "Unexpected conflicts in #include deletions: " +
346 llvm::toString(std::move(Err));
347 llvm_unreachable(ErrMsg.c_str());
354 } // namespace tooling