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"
19using namespace clang;
20
21namespace {
22void 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>(const_cast<FileEntry *>(
63           static_cast<const FileEntry *>(FI.getContentCache().OrigEntry))),
64       InclusionStack.data(), InclusionStack.size(), clientData);
65  }
66}
67} // namespace
68
69void 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