1 //===- CIndexInclusionStack.cpp - Clang-C Source Indexing Library ---------===//
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 // This file defines a callback mechanism for clients to get the inclusion
10 // stack from a translation unit.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "CIndexer.h"
15 #include "CXSourceLocation.h"
16 #include "CXTranslationUnit.h"
17 #include "clang/AST/DeclVisitor.h"
18 #include "clang/Frontend/ASTUnit.h"
19 using namespace clang;
20 
21 namespace {
22 void getInclusions(bool IsLocal, unsigned n, CXTranslationUnit TU,
23                    CXInclusionVisitor CB, CXClientData clientData) {
24   ASTUnit *CXXUnit = cxtu::getASTUnit(TU);
25   SourceManager &SM = CXXUnit->getSourceManager();
26   ASTContext &Ctx = CXXUnit->getASTContext();
27   SmallVector<CXSourceLocation, 10> InclusionStack;
28   const bool HasPreamble = SM.getPreambleFileID().isValid();
29 
30   for (unsigned i = 0 ; i < n ; ++i) {
31     bool Invalid = false;
32     const SrcMgr::SLocEntry &SL =
33         IsLocal ? SM.getLocalSLocEntry(i) : SM.getLoadedSLocEntry(i, &Invalid);
34     if (!SL.isFile() || Invalid)
35       continue;
36 
37     const SrcMgr::FileInfo &FI = SL.getFile();
38     if (!FI.getContentCache().OrigEntry)
39       continue;
40 
41     // If this is the main file, and there is a preamble, skip this SLoc. The
42     // inclusions of the preamble already showed it.
43     SourceLocation L = FI.getIncludeLoc();
44     if (HasPreamble && CXXUnit->isInMainFileID(L))
45       continue;
46 
47     // Build the inclusion stack.
48     InclusionStack.clear();
49     while (L.isValid()) {
50       PresumedLoc PLoc = SM.getPresumedLoc(L);
51       InclusionStack.push_back(cxloc::translateSourceLocation(Ctx, L));
52       L = PLoc.isValid()? PLoc.getIncludeLoc() : SourceLocation();
53     }
54 
55     // If there is a preamble, the last entry is the "inclusion" of that
56     // preamble into the main file, which has the bogus entry of main.c:1:1
57     if (HasPreamble && !InclusionStack.empty())
58       InclusionStack.pop_back();
59 
60     // Callback to the client.
61     // FIXME: We should have a function to construct CXFiles.
62     CB(static_cast<CXFile>(
63            const_cast<FileEntry *>(FI.getContentCache().OrigEntry)),
64        InclusionStack.data(), InclusionStack.size(), clientData);
65   }
66 }
67 } // namespace
68 
69 void clang_getInclusions(CXTranslationUnit TU, CXInclusionVisitor CB,
70                          CXClientData clientData) {
71   if (cxtu::isNotUsableTU(TU)) {
72     LOG_BAD_TU(TU);
73     return;
74   }
75 
76   SourceManager &SM = cxtu::getASTUnit(TU)->getSourceManager();
77   const unsigned n =  SM.local_sloc_entry_size();
78 
79   // In the case where all the SLocEntries are in an external source, traverse
80   // those SLocEntries as well.  This is the case where we are looking
81   // at the inclusion stack of an AST/PCH file. Also, if we are not looking at
82   // a AST/PCH file, but this file has a pre-compiled preamble, we also need
83   // to look in that file.
84   if (n == 1 || SM.getPreambleFileID().isValid()) {
85     getInclusions(/*IsLocal=*/false, SM.loaded_sloc_entry_size(), TU, CB,
86                   clientData);
87   }
88 
89   // Not a PCH/AST file. Note, if there is a preamble, it could still be that
90   // there are #includes in this file (e.g. for any include after the first
91   // declaration).
92   if (n != 1)
93     getInclusions(/*IsLocal=*/true, n, TU, CB, clientData);
94 }
95