1 //===-- FileSystem.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 "lldb/Host/FileSystem.h"
10
11 #include "lldb/Utility/DataBufferLLVM.h"
12 #include "lldb/Utility/LLDBAssert.h"
13 #include "lldb/Utility/TildeExpressionResolver.h"
14
15 #include "llvm/Support/Errc.h"
16 #include "llvm/Support/Errno.h"
17 #include "llvm/Support/Error.h"
18 #include "llvm/Support/FileSystem.h"
19 #include "llvm/Support/Path.h"
20 #include "llvm/Support/Program.h"
21 #include "llvm/Support/Threading.h"
22
23 #include <cerrno>
24 #include <climits>
25 #include <cstdarg>
26 #include <cstdio>
27 #include <fcntl.h>
28
29 #ifdef _WIN32
30 #include "lldb/Host/windows/windows.h"
31 #else
32 #include <sys/ioctl.h>
33 #include <sys/stat.h>
34 #include <termios.h>
35 #include <unistd.h>
36 #endif
37
38 #include <algorithm>
39 #include <fstream>
40 #include <optional>
41 #include <vector>
42
43 using namespace lldb;
44 using namespace lldb_private;
45 using namespace llvm;
46
Instance()47 FileSystem &FileSystem::Instance() { return *InstanceImpl(); }
48
Initialize()49 void FileSystem::Initialize() {
50 lldbassert(!InstanceImpl() && "Already initialized.");
51 InstanceImpl().emplace();
52 }
53
Initialize(IntrusiveRefCntPtr<vfs::FileSystem> fs)54 void FileSystem::Initialize(IntrusiveRefCntPtr<vfs::FileSystem> fs) {
55 lldbassert(!InstanceImpl() && "Already initialized.");
56 InstanceImpl().emplace(fs);
57 }
58
Terminate()59 void FileSystem::Terminate() {
60 lldbassert(InstanceImpl() && "Already terminated.");
61 InstanceImpl().reset();
62 }
63
InstanceImpl()64 std::optional<FileSystem> &FileSystem::InstanceImpl() {
65 static std::optional<FileSystem> g_fs;
66 return g_fs;
67 }
68
DirBegin(const FileSpec & file_spec,std::error_code & ec)69 vfs::directory_iterator FileSystem::DirBegin(const FileSpec &file_spec,
70 std::error_code &ec) {
71 if (!file_spec) {
72 ec = std::error_code(static_cast<int>(errc::no_such_file_or_directory),
73 std::system_category());
74 return {};
75 }
76 return DirBegin(file_spec.GetPath(), ec);
77 }
78
DirBegin(const Twine & dir,std::error_code & ec)79 vfs::directory_iterator FileSystem::DirBegin(const Twine &dir,
80 std::error_code &ec) {
81 return m_fs->dir_begin(dir, ec);
82 }
83
84 llvm::ErrorOr<vfs::Status>
GetStatus(const FileSpec & file_spec) const85 FileSystem::GetStatus(const FileSpec &file_spec) const {
86 if (!file_spec)
87 return std::error_code(static_cast<int>(errc::no_such_file_or_directory),
88 std::system_category());
89 return GetStatus(file_spec.GetPath());
90 }
91
GetStatus(const Twine & path) const92 llvm::ErrorOr<vfs::Status> FileSystem::GetStatus(const Twine &path) const {
93 return m_fs->status(path);
94 }
95
96 sys::TimePoint<>
GetModificationTime(const FileSpec & file_spec) const97 FileSystem::GetModificationTime(const FileSpec &file_spec) const {
98 if (!file_spec)
99 return sys::TimePoint<>();
100 return GetModificationTime(file_spec.GetPath());
101 }
102
GetModificationTime(const Twine & path) const103 sys::TimePoint<> FileSystem::GetModificationTime(const Twine &path) const {
104 ErrorOr<vfs::Status> status = m_fs->status(path);
105 if (!status)
106 return sys::TimePoint<>();
107 return status->getLastModificationTime();
108 }
109
GetByteSize(const FileSpec & file_spec) const110 uint64_t FileSystem::GetByteSize(const FileSpec &file_spec) const {
111 if (!file_spec)
112 return 0;
113 return GetByteSize(file_spec.GetPath());
114 }
115
GetByteSize(const Twine & path) const116 uint64_t FileSystem::GetByteSize(const Twine &path) const {
117 ErrorOr<vfs::Status> status = m_fs->status(path);
118 if (!status)
119 return 0;
120 return status->getSize();
121 }
122
GetPermissions(const FileSpec & file_spec) const123 uint32_t FileSystem::GetPermissions(const FileSpec &file_spec) const {
124 return GetPermissions(file_spec.GetPath());
125 }
126
GetPermissions(const FileSpec & file_spec,std::error_code & ec) const127 uint32_t FileSystem::GetPermissions(const FileSpec &file_spec,
128 std::error_code &ec) const {
129 if (!file_spec)
130 return sys::fs::perms::perms_not_known;
131 return GetPermissions(file_spec.GetPath(), ec);
132 }
133
GetPermissions(const Twine & path) const134 uint32_t FileSystem::GetPermissions(const Twine &path) const {
135 std::error_code ec;
136 return GetPermissions(path, ec);
137 }
138
GetPermissions(const Twine & path,std::error_code & ec) const139 uint32_t FileSystem::GetPermissions(const Twine &path,
140 std::error_code &ec) const {
141 ErrorOr<vfs::Status> status = m_fs->status(path);
142 if (!status) {
143 ec = status.getError();
144 return sys::fs::perms::perms_not_known;
145 }
146 return status->getPermissions();
147 }
148
Exists(const Twine & path) const149 bool FileSystem::Exists(const Twine &path) const { return m_fs->exists(path); }
150
Exists(const FileSpec & file_spec) const151 bool FileSystem::Exists(const FileSpec &file_spec) const {
152 return file_spec && Exists(file_spec.GetPath());
153 }
154
Readable(const Twine & path) const155 bool FileSystem::Readable(const Twine &path) const {
156 return GetPermissions(path) & sys::fs::perms::all_read;
157 }
158
Readable(const FileSpec & file_spec) const159 bool FileSystem::Readable(const FileSpec &file_spec) const {
160 return file_spec && Readable(file_spec.GetPath());
161 }
162
IsDirectory(const Twine & path) const163 bool FileSystem::IsDirectory(const Twine &path) const {
164 ErrorOr<vfs::Status> status = m_fs->status(path);
165 if (!status)
166 return false;
167 return status->isDirectory();
168 }
169
IsDirectory(const FileSpec & file_spec) const170 bool FileSystem::IsDirectory(const FileSpec &file_spec) const {
171 return file_spec && IsDirectory(file_spec.GetPath());
172 }
173
IsLocal(const Twine & path) const174 bool FileSystem::IsLocal(const Twine &path) const {
175 bool b = false;
176 m_fs->isLocal(path, b);
177 return b;
178 }
179
IsLocal(const FileSpec & file_spec) const180 bool FileSystem::IsLocal(const FileSpec &file_spec) const {
181 return file_spec && IsLocal(file_spec.GetPath());
182 }
183
EnumerateDirectory(Twine path,bool find_directories,bool find_files,bool find_other,EnumerateDirectoryCallbackType callback,void * callback_baton)184 void FileSystem::EnumerateDirectory(Twine path, bool find_directories,
185 bool find_files, bool find_other,
186 EnumerateDirectoryCallbackType callback,
187 void *callback_baton) {
188 std::error_code EC;
189 vfs::recursive_directory_iterator Iter(*m_fs, path, EC);
190 vfs::recursive_directory_iterator End;
191 for (; Iter != End && !EC; Iter.increment(EC)) {
192 const auto &Item = *Iter;
193 ErrorOr<vfs::Status> Status = m_fs->status(Item.path());
194 if (!Status)
195 break;
196 if (!find_files && Status->isRegularFile())
197 continue;
198 if (!find_directories && Status->isDirectory())
199 continue;
200 if (!find_other && Status->isOther())
201 continue;
202
203 auto Result = callback(callback_baton, Status->getType(), Item.path());
204 if (Result == eEnumerateDirectoryResultQuit)
205 return;
206 if (Result == eEnumerateDirectoryResultNext) {
207 // Default behavior is to recurse. Opt out if the callback doesn't want
208 // this behavior.
209 Iter.no_push();
210 }
211 }
212 }
213
MakeAbsolute(SmallVectorImpl<char> & path) const214 std::error_code FileSystem::MakeAbsolute(SmallVectorImpl<char> &path) const {
215 return m_fs->makeAbsolute(path);
216 }
217
MakeAbsolute(FileSpec & file_spec) const218 std::error_code FileSystem::MakeAbsolute(FileSpec &file_spec) const {
219 SmallString<128> path;
220 file_spec.GetPath(path, false);
221
222 auto EC = MakeAbsolute(path);
223 if (EC)
224 return EC;
225
226 FileSpec new_file_spec(path, file_spec.GetPathStyle());
227 file_spec = new_file_spec;
228 return {};
229 }
230
GetRealPath(const Twine & path,SmallVectorImpl<char> & output) const231 std::error_code FileSystem::GetRealPath(const Twine &path,
232 SmallVectorImpl<char> &output) const {
233 return m_fs->getRealPath(path, output);
234 }
235
Resolve(SmallVectorImpl<char> & path)236 void FileSystem::Resolve(SmallVectorImpl<char> &path) {
237 if (path.empty())
238 return;
239
240 // Resolve tilde in path.
241 SmallString<128> resolved(path.begin(), path.end());
242 StandardTildeExpressionResolver Resolver;
243 Resolver.ResolveFullPath(llvm::StringRef(path.begin(), path.size()),
244 resolved);
245
246 // Try making the path absolute if it exists.
247 SmallString<128> absolute(resolved.begin(), resolved.end());
248 MakeAbsolute(absolute);
249
250 path.clear();
251 if (Exists(absolute)) {
252 path.append(absolute.begin(), absolute.end());
253 } else {
254 path.append(resolved.begin(), resolved.end());
255 }
256 }
257
Resolve(FileSpec & file_spec)258 void FileSystem::Resolve(FileSpec &file_spec) {
259 if (!file_spec)
260 return;
261
262 // Extract path from the FileSpec.
263 SmallString<128> path;
264 file_spec.GetPath(path);
265
266 // Resolve the path.
267 Resolve(path);
268
269 // Update the FileSpec with the resolved path.
270 if (file_spec.GetFilename().IsEmpty())
271 file_spec.SetDirectory(path);
272 else
273 file_spec.SetPath(path);
274 file_spec.SetIsResolved(true);
275 }
276
277 template <typename T>
GetMemoryBuffer(const llvm::Twine & path,uint64_t size,uint64_t offset,bool is_volatile)278 static std::unique_ptr<T> GetMemoryBuffer(const llvm::Twine &path,
279 uint64_t size, uint64_t offset,
280 bool is_volatile) {
281 std::unique_ptr<T> buffer;
282 if (size == 0) {
283 auto buffer_or_error = T::getFile(path, is_volatile);
284 if (!buffer_or_error)
285 return nullptr;
286 buffer = std::move(*buffer_or_error);
287 } else {
288 auto buffer_or_error = T::getFileSlice(path, size, offset, is_volatile);
289 if (!buffer_or_error)
290 return nullptr;
291 buffer = std::move(*buffer_or_error);
292 }
293 return buffer;
294 }
295
296 std::shared_ptr<WritableDataBuffer>
CreateWritableDataBuffer(const llvm::Twine & path,uint64_t size,uint64_t offset)297 FileSystem::CreateWritableDataBuffer(const llvm::Twine &path, uint64_t size,
298 uint64_t offset) {
299 const bool is_volatile = !IsLocal(path);
300 auto buffer = GetMemoryBuffer<llvm::WritableMemoryBuffer>(path, size, offset,
301 is_volatile);
302 if (!buffer)
303 return {};
304 return std::shared_ptr<WritableDataBufferLLVM>(
305 new WritableDataBufferLLVM(std::move(buffer)));
306 }
307
308 std::shared_ptr<DataBuffer>
CreateDataBuffer(const llvm::Twine & path,uint64_t size,uint64_t offset)309 FileSystem::CreateDataBuffer(const llvm::Twine &path, uint64_t size,
310 uint64_t offset) {
311 const bool is_volatile = !IsLocal(path);
312 auto buffer =
313 GetMemoryBuffer<llvm::MemoryBuffer>(path, size, offset, is_volatile);
314 if (!buffer)
315 return {};
316 return std::shared_ptr<DataBufferLLVM>(new DataBufferLLVM(std::move(buffer)));
317 }
318
319 std::shared_ptr<WritableDataBuffer>
CreateWritableDataBuffer(const FileSpec & file_spec,uint64_t size,uint64_t offset)320 FileSystem::CreateWritableDataBuffer(const FileSpec &file_spec, uint64_t size,
321 uint64_t offset) {
322 return CreateWritableDataBuffer(file_spec.GetPath(), size, offset);
323 }
324
325 std::shared_ptr<DataBuffer>
CreateDataBuffer(const FileSpec & file_spec,uint64_t size,uint64_t offset)326 FileSystem::CreateDataBuffer(const FileSpec &file_spec, uint64_t size,
327 uint64_t offset) {
328 return CreateDataBuffer(file_spec.GetPath(), size, offset);
329 }
330
ResolveExecutableLocation(FileSpec & file_spec)331 bool FileSystem::ResolveExecutableLocation(FileSpec &file_spec) {
332 // If the directory is set there's nothing to do.
333 ConstString directory = file_spec.GetDirectory();
334 if (directory)
335 return false;
336
337 // We cannot look for a file if there's no file name.
338 ConstString filename = file_spec.GetFilename();
339 if (!filename)
340 return false;
341
342 // Search for the file on the host.
343 const std::string filename_str(filename.GetCString());
344 llvm::ErrorOr<std::string> error_or_path =
345 llvm::sys::findProgramByName(filename_str);
346 if (!error_or_path)
347 return false;
348
349 // findProgramByName returns "." if it can't find the file.
350 llvm::StringRef path = *error_or_path;
351 llvm::StringRef parent = llvm::sys::path::parent_path(path);
352 if (parent.empty() || parent == ".")
353 return false;
354
355 // Make sure that the result exists.
356 FileSpec result(*error_or_path);
357 if (!Exists(result))
358 return false;
359
360 file_spec = result;
361 return true;
362 }
363
GetHomeDirectory(SmallVectorImpl<char> & path) const364 bool FileSystem::GetHomeDirectory(SmallVectorImpl<char> &path) const {
365 if (!m_home_directory.empty()) {
366 path.assign(m_home_directory.begin(), m_home_directory.end());
367 return true;
368 }
369 return llvm::sys::path::home_directory(path);
370 }
371
GetHomeDirectory(FileSpec & file_spec) const372 bool FileSystem::GetHomeDirectory(FileSpec &file_spec) const {
373 SmallString<128> home_dir;
374 if (!GetHomeDirectory(home_dir))
375 return false;
376 file_spec.SetPath(home_dir);
377 return true;
378 }
379
OpenWithFS(const FileSystem & fs,const char * path,int flags,int mode)380 static int OpenWithFS(const FileSystem &fs, const char *path, int flags,
381 int mode) {
382 return const_cast<FileSystem &>(fs).Open(path, flags, mode);
383 }
384
GetOpenFlags(File::OpenOptions options)385 static int GetOpenFlags(File::OpenOptions options) {
386 int open_flags = 0;
387 File::OpenOptions rw =
388 options & (File::eOpenOptionReadOnly | File::eOpenOptionWriteOnly |
389 File::eOpenOptionReadWrite);
390 if (rw == File::eOpenOptionWriteOnly || rw == File::eOpenOptionReadWrite) {
391 if (rw == File::eOpenOptionReadWrite)
392 open_flags |= O_RDWR;
393 else
394 open_flags |= O_WRONLY;
395
396 if (options & File::eOpenOptionAppend)
397 open_flags |= O_APPEND;
398
399 if (options & File::eOpenOptionTruncate)
400 open_flags |= O_TRUNC;
401
402 if (options & File::eOpenOptionCanCreate)
403 open_flags |= O_CREAT;
404
405 if (options & File::eOpenOptionCanCreateNewOnly)
406 open_flags |= O_CREAT | O_EXCL;
407 } else if (rw == File::eOpenOptionReadOnly) {
408 open_flags |= O_RDONLY;
409
410 #ifndef _WIN32
411 if (options & File::eOpenOptionDontFollowSymlinks)
412 open_flags |= O_NOFOLLOW;
413 #endif
414 }
415
416 #ifndef _WIN32
417 if (options & File::eOpenOptionNonBlocking)
418 open_flags |= O_NONBLOCK;
419 if (options & File::eOpenOptionCloseOnExec)
420 open_flags |= O_CLOEXEC;
421 #else
422 open_flags |= O_BINARY;
423 #endif
424
425 return open_flags;
426 }
427
GetOpenMode(uint32_t permissions)428 static mode_t GetOpenMode(uint32_t permissions) {
429 mode_t mode = 0;
430 if (permissions & lldb::eFilePermissionsUserRead)
431 mode |= S_IRUSR;
432 if (permissions & lldb::eFilePermissionsUserWrite)
433 mode |= S_IWUSR;
434 if (permissions & lldb::eFilePermissionsUserExecute)
435 mode |= S_IXUSR;
436 if (permissions & lldb::eFilePermissionsGroupRead)
437 mode |= S_IRGRP;
438 if (permissions & lldb::eFilePermissionsGroupWrite)
439 mode |= S_IWGRP;
440 if (permissions & lldb::eFilePermissionsGroupExecute)
441 mode |= S_IXGRP;
442 if (permissions & lldb::eFilePermissionsWorldRead)
443 mode |= S_IROTH;
444 if (permissions & lldb::eFilePermissionsWorldWrite)
445 mode |= S_IWOTH;
446 if (permissions & lldb::eFilePermissionsWorldExecute)
447 mode |= S_IXOTH;
448 return mode;
449 }
450
Open(const FileSpec & file_spec,File::OpenOptions options,uint32_t permissions,bool should_close_fd)451 Expected<FileUP> FileSystem::Open(const FileSpec &file_spec,
452 File::OpenOptions options,
453 uint32_t permissions, bool should_close_fd) {
454 const int open_flags = GetOpenFlags(options);
455 const mode_t open_mode =
456 (open_flags & O_CREAT) ? GetOpenMode(permissions) : 0;
457
458 auto path = file_spec.GetPath();
459
460 int descriptor = llvm::sys::RetryAfterSignal(
461 -1, OpenWithFS, *this, path.c_str(), open_flags, open_mode);
462
463 if (!File::DescriptorIsValid(descriptor))
464 return llvm::errorCodeToError(
465 std::error_code(errno, std::system_category()));
466
467 auto file = std::unique_ptr<File>(
468 new NativeFile(descriptor, options, should_close_fd));
469 assert(file->IsValid());
470 return std::move(file);
471 }
472
SetHomeDirectory(std::string home_directory)473 void FileSystem::SetHomeDirectory(std::string home_directory) {
474 m_home_directory = std::move(home_directory);
475 }
476
RemoveFile(const FileSpec & file_spec)477 Status FileSystem::RemoveFile(const FileSpec &file_spec) {
478 return RemoveFile(file_spec.GetPath());
479 }
480
RemoveFile(const llvm::Twine & path)481 Status FileSystem::RemoveFile(const llvm::Twine &path) {
482 return Status(llvm::sys::fs::remove(path));
483 }
484