1//===-- PathMappingList.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 <climits>
10#include <cstring>
11#include <optional>
12
13#include "lldb/Host/FileSystem.h"
14#include "lldb/Host/PosixApi.h"
15#include "lldb/Target/PathMappingList.h"
16#include "lldb/Utility/FileSpec.h"
17#include "lldb/Utility/Status.h"
18#include "lldb/Utility/Stream.h"
19#include "lldb/lldb-private-enumerations.h"
20
21using namespace lldb;
22using namespace lldb_private;
23
24namespace {
25 // We must normalize our path pairs that we store because if we don't then
26 // things won't always work. We found a case where if we did:
27 // (lldb) settings set target.source-map . /tmp
28 // We would store a path pairs of "." and "/tmp" as raw strings. If the debug
29 // info contains "./foo/bar.c", the path will get normalized to "foo/bar.c".
30 // When PathMappingList::RemapPath() is called, it expects the path to start
31 // with the raw path pair, which doesn't work anymore because the paths have
32 // been normalized when the debug info was loaded. So we need to store
33 // nomalized path pairs to ensure things match up.
34std::string NormalizePath(llvm::StringRef path) {
35 // If we use "path" to construct a FileSpec, it will normalize the path for
36 // us. We then grab the string.
37 return FileSpec(path).GetPath();
38}
39}
40// PathMappingList constructor
41PathMappingList::PathMappingList() : m_pairs() {}
42
43PathMappingList::PathMappingList(ChangedCallback callback, void *callback_baton)
44 : m_pairs(), m_callback(callback), m_callback_baton(callback_baton) {}
45
46PathMappingList::PathMappingList(const PathMappingList &rhs)
47 : m_pairs(rhs.m_pairs) {}
48
49const PathMappingList &PathMappingList::operator=(const PathMappingList &rhs) {
50 if (this != &rhs) {
51 std::scoped_lock<std::recursive_mutex, std::recursive_mutex> locks(m_mutex, rhs.m_mutex);
52 m_pairs = rhs.m_pairs;
53 m_callback = nullptr;
54 m_callback_baton = nullptr;
55 m_mod_id = rhs.m_mod_id;
56 }
57 return *this;
58}
59
60PathMappingList::~PathMappingList() = default;
61
62void PathMappingList::Append(llvm::StringRef path, llvm::StringRef replacement,
63 bool notify) {
64 std::lock_guard<std::recursive_mutex> lock(m_mutex);
65 ++m_mod_id;
66 m_pairs.emplace_back(args: pair(NormalizePath(path), NormalizePath(path: replacement)));
67 if (notify && m_callback)
68 m_callback(*this, m_callback_baton);
69}
70
71void PathMappingList::Append(const PathMappingList &rhs, bool notify) {
72 std::scoped_lock<std::recursive_mutex, std::recursive_mutex> locks(m_mutex, rhs.m_mutex);
73 ++m_mod_id;
74 if (!rhs.m_pairs.empty()) {
75 const_iterator pos, end = rhs.m_pairs.end();
76 for (pos = rhs.m_pairs.begin(); pos != end; ++pos)
77 m_pairs.push_back(x: *pos);
78 if (notify && m_callback)
79 m_callback(*this, m_callback_baton);
80 }
81}
82
83bool PathMappingList::AppendUnique(llvm::StringRef path,
84 llvm::StringRef replacement, bool notify) {
85 auto normalized_path = NormalizePath(path);
86 auto normalized_replacement = NormalizePath(path: replacement);
87 std::lock_guard<std::recursive_mutex> lock(m_mutex);
88 for (const auto &pair : m_pairs) {
89 if (pair.first.GetStringRef().equals(RHS: normalized_path) &&
90 pair.second.GetStringRef().equals(RHS: normalized_replacement))
91 return false;
92 }
93 Append(path, replacement, notify);
94 return true;
95}
96
97void PathMappingList::Insert(llvm::StringRef path, llvm::StringRef replacement,
98 uint32_t index, bool notify) {
99 std::lock_guard<std::recursive_mutex> lock(m_mutex);
100 ++m_mod_id;
101 iterator insert_iter;
102 if (index >= m_pairs.size())
103 insert_iter = m_pairs.end();
104 else
105 insert_iter = m_pairs.begin() + index;
106 m_pairs.emplace(position: insert_iter, args: pair(NormalizePath(path),
107 NormalizePath(path: replacement)));
108 if (notify && m_callback)
109 m_callback(*this, m_callback_baton);
110}
111
112bool PathMappingList::Replace(llvm::StringRef path, llvm::StringRef replacement,
113 uint32_t index, bool notify) {
114 std::lock_guard<std::recursive_mutex> lock(m_mutex);
115 if (index >= m_pairs.size())
116 return false;
117 ++m_mod_id;
118 m_pairs[index] = pair(NormalizePath(path), NormalizePath(path: replacement));
119 if (notify && m_callback)
120 m_callback(*this, m_callback_baton);
121 return true;
122}
123
124bool PathMappingList::Remove(size_t index, bool notify) {
125 std::lock_guard<std::recursive_mutex> lock(m_mutex);
126 if (index >= m_pairs.size())
127 return false;
128
129 ++m_mod_id;
130 iterator iter = m_pairs.begin() + index;
131 m_pairs.erase(position: iter);
132 if (notify && m_callback)
133 m_callback(*this, m_callback_baton);
134 return true;
135}
136
137// For clients which do not need the pair index dumped, pass a pair_index >= 0
138// to only dump the indicated pair.
139void PathMappingList::Dump(Stream *s, int pair_index) {
140 std::lock_guard<std::recursive_mutex> lock(m_mutex);
141 unsigned int numPairs = m_pairs.size();
142
143 if (pair_index < 0) {
144 unsigned int index;
145 for (index = 0; index < numPairs; ++index)
146 s->Printf(format: "[%d] \"%s\" -> \"%s\"\n", index,
147 m_pairs[index].first.GetCString(),
148 m_pairs[index].second.GetCString());
149 } else {
150 if (static_cast<unsigned int>(pair_index) < numPairs)
151 s->Printf(format: "%s -> %s", m_pairs[pair_index].first.GetCString(),
152 m_pairs[pair_index].second.GetCString());
153 }
154}
155
156llvm::json::Value PathMappingList::ToJSON() {
157 llvm::json::Array entries;
158 std::lock_guard<std::recursive_mutex> lock(m_mutex);
159 for (const auto &pair : m_pairs) {
160 llvm::json::Array entry{pair.first.GetStringRef().str(),
161 pair.second.GetStringRef().str()};
162 entries.emplace_back(A: std::move(entry));
163 }
164 return entries;
165}
166
167void PathMappingList::Clear(bool notify) {
168 std::lock_guard<std::recursive_mutex> lock(m_mutex);
169 if (!m_pairs.empty())
170 ++m_mod_id;
171 m_pairs.clear();
172 if (notify && m_callback)
173 m_callback(*this, m_callback_baton);
174}
175
176bool PathMappingList::RemapPath(ConstString path,
177 ConstString &new_path) const {
178 if (std::optional<FileSpec> remapped = RemapPath(path: path.GetStringRef())) {
179 new_path.SetString(remapped->GetPath());
180 return true;
181 }
182 return false;
183}
184
185/// Append components to path, applying style.
186static void AppendPathComponents(FileSpec &path, llvm::StringRef components,
187 llvm::sys::path::Style style) {
188 auto component = llvm::sys::path::begin(path: components, style);
189 auto e = llvm::sys::path::end(path: components);
190 while (component != e &&
191 llvm::sys::path::is_separator(value: *component->data(), style))
192 ++component;
193 for (; component != e; ++component)
194 path.AppendPathComponent(component: *component);
195}
196
197std::optional<FileSpec> PathMappingList::RemapPath(llvm::StringRef mapping_path,
198 bool only_if_exists) const {
199 std::lock_guard<std::recursive_mutex> lock(m_mutex);
200 if (m_pairs.empty() || mapping_path.empty())
201 return {};
202 LazyBool path_is_relative = eLazyBoolCalculate;
203
204 for (const auto &it : m_pairs) {
205 llvm::StringRef prefix = it.first.GetStringRef();
206 // We create a copy of mapping_path because StringRef::consume_from
207 // effectively modifies the instance itself.
208 llvm::StringRef path = mapping_path;
209 if (!path.consume_front(Prefix: prefix)) {
210 // Relative paths won't have a leading "./" in them unless "." is the
211 // only thing in the relative path so we need to work around "."
212 // carefully.
213 if (prefix != ".")
214 continue;
215 // We need to figure out if the "path" argument is relative. If it is,
216 // then we should remap, else skip this entry.
217 if (path_is_relative == eLazyBoolCalculate) {
218 path_is_relative =
219 FileSpec(path).IsRelative() ? eLazyBoolYes : eLazyBoolNo;
220 }
221 if (!path_is_relative)
222 continue;
223 }
224 FileSpec remapped(it.second.GetStringRef());
225 auto orig_style = FileSpec::GuessPathStyle(absolute_path: prefix).value_or(
226 u: llvm::sys::path::Style::native);
227 AppendPathComponents(path&: remapped, components: path, style: orig_style);
228 if (!only_if_exists || FileSystem::Instance().Exists(file_spec: remapped))
229 return remapped;
230 }
231 return {};
232}
233
234std::optional<llvm::StringRef>
235PathMappingList::ReverseRemapPath(const FileSpec &file, FileSpec &fixed) const {
236 std::string path = file.GetPath();
237 llvm::StringRef path_ref(path);
238 std::lock_guard<std::recursive_mutex> lock(m_mutex);
239 for (const auto &it : m_pairs) {
240 llvm::StringRef removed_prefix = it.second.GetStringRef();
241 if (!path_ref.consume_front(Prefix: it.second.GetStringRef()))
242 continue;
243 auto orig_file = it.first.GetStringRef();
244 auto orig_style = FileSpec::GuessPathStyle(absolute_path: orig_file).value_or(
245 u: llvm::sys::path::Style::native);
246 fixed.SetFile(path: orig_file, style: orig_style);
247 AppendPathComponents(path&: fixed, components: path_ref, style: orig_style);
248 return removed_prefix;
249 }
250 return std::nullopt;
251}
252
253std::optional<FileSpec>
254PathMappingList::FindFile(const FileSpec &orig_spec) const {
255 // We must normalize the orig_spec again using the host's path style,
256 // otherwise there will be mismatch between the host and remote platform
257 // if they use different path styles.
258 if (auto remapped = RemapPath(mapping_path: NormalizePath(path: orig_spec.GetPath()),
259 /*only_if_exists=*/true))
260 return remapped;
261
262 return {};
263}
264
265bool PathMappingList::Replace(llvm::StringRef path, llvm::StringRef new_path,
266 bool notify) {
267 std::lock_guard<std::recursive_mutex> lock(m_mutex);
268 uint32_t idx = FindIndexForPath(path);
269 if (idx < m_pairs.size()) {
270 ++m_mod_id;
271 m_pairs[idx].second = ConstString(new_path);
272 if (notify && m_callback)
273 m_callback(*this, m_callback_baton);
274 return true;
275 }
276 return false;
277}
278
279bool PathMappingList::Remove(ConstString path, bool notify) {
280 std::lock_guard<std::recursive_mutex> lock(m_mutex);
281 iterator pos = FindIteratorForPath(path);
282 if (pos != m_pairs.end()) {
283 ++m_mod_id;
284 m_pairs.erase(position: pos);
285 if (notify && m_callback)
286 m_callback(*this, m_callback_baton);
287 return true;
288 }
289 return false;
290}
291
292PathMappingList::const_iterator
293PathMappingList::FindIteratorForPath(ConstString path) const {
294 std::lock_guard<std::recursive_mutex> lock(m_mutex);
295 const_iterator pos;
296 const_iterator begin = m_pairs.begin();
297 const_iterator end = m_pairs.end();
298
299 for (pos = begin; pos != end; ++pos) {
300 if (pos->first == path)
301 break;
302 }
303 return pos;
304}
305
306PathMappingList::iterator
307PathMappingList::FindIteratorForPath(ConstString path) {
308 std::lock_guard<std::recursive_mutex> lock(m_mutex);
309 iterator pos;
310 iterator begin = m_pairs.begin();
311 iterator end = m_pairs.end();
312
313 for (pos = begin; pos != end; ++pos) {
314 if (pos->first == path)
315 break;
316 }
317 return pos;
318}
319
320bool PathMappingList::GetPathsAtIndex(uint32_t idx, ConstString &path,
321 ConstString &new_path) const {
322 std::lock_guard<std::recursive_mutex> lock(m_mutex);
323 if (idx < m_pairs.size()) {
324 path = m_pairs[idx].first;
325 new_path = m_pairs[idx].second;
326 return true;
327 }
328 return false;
329}
330
331uint32_t PathMappingList::FindIndexForPath(llvm::StringRef orig_path) const {
332 const ConstString path = ConstString(NormalizePath(path: orig_path));
333 std::lock_guard<std::recursive_mutex> lock(m_mutex);
334 const_iterator pos;
335 const_iterator begin = m_pairs.begin();
336 const_iterator end = m_pairs.end();
337
338 for (pos = begin; pos != end; ++pos) {
339 if (pos->first == path)
340 return std::distance(first: begin, last: pos);
341 }
342 return UINT32_MAX;
343}
344

source code of lldb/source/Target/PathMappingList.cpp