1//===-- CppModuleConfiguration.cpp ----------------------------------------===//
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#include "CppModuleConfiguration.h"
10
11#include "ClangHost.h"
12#include "lldb/Host/FileSystem.h"
13
14using namespace lldb_private;
15
16bool CppModuleConfiguration::SetOncePath::TrySet(llvm::StringRef path) {
17  // Setting for the first time always works.
18  if (m_first) {
19    m_path = path.str();
20    m_valid = true;
21    m_first = false;
22    return true;
23  }
24  // Changing the path to the same value is fine.
25  if (m_path == path)
26    return true;
27
28  // Changing the path after it was already set is not allowed.
29  m_valid = false;
30  return false;
31}
32
33bool CppModuleConfiguration::analyzeFile(const FileSpec &f) {
34  using namespace llvm::sys::path;
35  // Convert to slashes to make following operations simpler.
36  std::string dir_buffer = convert_to_slash(f.GetDirectory().GetStringRef());
37  llvm::StringRef posix_dir(dir_buffer);
38
39  // Check for /c++/vX/ that is used by libc++.
40  static llvm::Regex libcpp_regex(R"regex(/c[+][+]/v[0-9]/)regex");
41  if (libcpp_regex.match(f.GetPath())) {
42    // Strip away libc++'s /experimental directory if there is one.
43    posix_dir.consume_back("/experimental");
44    return m_std_inc.TrySet(posix_dir);
45  }
46
47  // Check for /usr/include. On Linux this might be /usr/include/bits, so
48  // we should remove that '/bits' suffix to get the actual include directory.
49  if (posix_dir.endswith("/usr/include/bits"))
50    posix_dir.consume_back("/bits");
51  if (posix_dir.endswith("/usr/include"))
52    return m_c_inc.TrySet(posix_dir);
53
54  // File wasn't interesting, continue analyzing.
55  return true;
56}
57
58bool CppModuleConfiguration::hasValidConfig() {
59  // We all these include directories to have a valid usable configuration.
60  return m_c_inc.Valid() && m_std_inc.Valid();
61}
62
63CppModuleConfiguration::CppModuleConfiguration(
64    const FileSpecList &support_files) {
65  // Analyze all files we were given to build the configuration.
66  bool error = !llvm::all_of(support_files,
67                             std::bind(&CppModuleConfiguration::analyzeFile,
68                                       this, std::placeholders::_1));
69  // If we have a valid configuration at this point, set the
70  // include directories and module list that should be used.
71  if (!error && hasValidConfig()) {
72    // Calculate the resource directory for LLDB.
73    llvm::SmallString<256> resource_dir;
74    llvm::sys::path::append(resource_dir, GetClangResourceDir().GetPath(),
75                            "include");
76    m_resource_inc = resource_dir.str();
77
78    // This order matches the way Clang orders these directories.
79    m_include_dirs = {m_std_inc.Get(), m_resource_inc, m_c_inc.Get()};
80    m_imported_modules = {"std"};
81  }
82}
83