1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
| //===--------------------- ModuleCache.cpp ----------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "lldb/Target/ModuleCache.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/ModuleList.h"
#include "lldb/Core/ModuleSpec.h"
#include "lldb/Host/File.h"
#include "lldb/Host/LockFile.h"
#include "lldb/Utility/Log.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/FileUtilities.h"
#include <assert.h>
#include <cstdio>
using namespace lldb;
using namespace lldb_private;
namespace {
const char *kModulesSubdir = ".cache";
const char *kLockDirName = ".lock";
const char *kTempFileName = ".temp";
const char *kTempSymFileName = ".symtemp";
const char *kSymFileExtension = ".sym";
const char *kFSIllegalChars = "\\/:*?\"<>|";
std::string GetEscapedHostname(const char *hostname) {
if (hostname == nullptr)
hostname = "unknown";
std::string result(hostname);
size_t size = result.size();
for (size_t i = 0; i < size; ++i) {
if ((result[i] >= 1 && result[i] <= 31) ||
strchr(kFSIllegalChars, result[i]) != nullptr)
result[i] = '_';
}
return result;
}
class ModuleLock {
private:
FileUP m_file_up;
std::unique_ptr<lldb_private::LockFile> m_lock;
FileSpec m_file_spec;
public:
ModuleLock(const FileSpec &root_dir_spec, const UUID &uuid, Status &error);
void Delete();
};
static FileSpec JoinPath(const FileSpec &path1, const char *path2) {
FileSpec result_spec(path1);
result_spec.AppendPathComponent(path2);
return result_spec;
}
static Status MakeDirectory(const FileSpec &dir_path) {
namespace fs = llvm::sys::fs;
return fs::create_directories(dir_path.GetPath(), true, fs::perms::owner_all);
}
FileSpec GetModuleDirectory(const FileSpec &root_dir_spec, const UUID &uuid) {
const auto modules_dir_spec = JoinPath(root_dir_spec, kModulesSubdir);
return JoinPath(modules_dir_spec, uuid.GetAsString().c_str());
}
FileSpec GetSymbolFileSpec(const FileSpec &module_file_spec) {
return FileSpec(module_file_spec.GetPath() + kSymFileExtension);
}
void DeleteExistingModule(const FileSpec &root_dir_spec,
const FileSpec &sysroot_module_path_spec) {
Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_MODULES));
UUID module_uuid;
{
auto module_sp =
std::make_shared<Module>(ModuleSpec(sysroot_module_path_spec));
module_uuid = module_sp->GetUUID();
}
if (!module_uuid.IsValid())
return;
Status error;
ModuleLock lock(root_dir_spec, module_uuid, error);
if (error.Fail()) {
LLDB_LOGF(log, "Failed to lock module %s: %s",
module_uuid.GetAsString().c_str(), error.AsCString());
}
namespace fs = llvm::sys::fs;
fs::file_status st;
if (status(sysroot_module_path_spec.GetPath(), st))
return;
if (st.getLinkCount() > 2) // module is referred by other hosts.
return;
const auto module_spec_dir = GetModuleDirectory(root_dir_spec, module_uuid);
llvm::sys::fs::remove_directories(module_spec_dir.GetPath());
lock.Delete();
}
void DecrementRefExistingModule(const FileSpec &root_dir_spec,
const FileSpec &sysroot_module_path_spec) {
// Remove $platform/.cache/$uuid folder if nobody else references it.
DeleteExistingModule(root_dir_spec, sysroot_module_path_spec);
// Remove sysroot link.
llvm::sys::fs::remove(sysroot_module_path_spec.GetPath());
FileSpec symfile_spec = GetSymbolFileSpec(sysroot_module_path_spec);
llvm::sys::fs::remove(symfile_spec.GetPath());
}
Status CreateHostSysRootModuleLink(const FileSpec &root_dir_spec,
const char *hostname,
const FileSpec &platform_module_spec,
const FileSpec &local_module_spec,
bool delete_existing) {
const auto sysroot_module_path_spec =
JoinPath(JoinPath(root_dir_spec, hostname),
platform_module_spec.GetPath().c_str());
if (FileSystem::Instance().Exists(sysroot_module_path_spec)) {
if (!delete_existing)
return Status();
DecrementRefExistingModule(root_dir_spec, sysroot_module_path_spec);
}
const auto error = MakeDirectory(
FileSpec(sysroot_module_path_spec.GetDirectory().AsCString()));
if (error.Fail())
return error;
return llvm::sys::fs::create_hard_link(local_module_spec.GetPath(),
sysroot_module_path_spec.GetPath());
}
} // namespace
ModuleLock::ModuleLock(const FileSpec &root_dir_spec, const UUID &uuid,
Status &error) {
const auto lock_dir_spec = JoinPath(root_dir_spec, kLockDirName);
error = MakeDirectory(lock_dir_spec);
if (error.Fail())
return;
m_file_spec = JoinPath(lock_dir_spec, uuid.GetAsString().c_str());
auto file = FileSystem::Instance().Open(
m_file_spec, File::eOpenOptionWrite | File::eOpenOptionCanCreate |
File::eOpenOptionCloseOnExec);
if (file)
m_file_up = std::move(file.get());
else {
m_file_up.reset();
error = Status(file.takeError());
return;
}
m_lock.reset(new lldb_private::LockFile(m_file_up->GetDescriptor()));
error = m_lock->WriteLock(0, 1);
if (error.Fail())
error.SetErrorStringWithFormat("Failed to lock file: %s",
error.AsCString());
}
void ModuleLock::Delete() {
if (!m_file_up)
return;
m_file_up->Close();
m_file_up.reset();
llvm::sys::fs::remove(m_file_spec.GetPath());
}
/////////////////////////////////////////////////////////////////////////
Status ModuleCache::Put(const FileSpec &root_dir_spec, const char *hostname,
const ModuleSpec &module_spec, const FileSpec &tmp_file,
const FileSpec &target_file) {
const auto module_spec_dir =
GetModuleDirectory(root_dir_spec, module_spec.GetUUID());
const auto module_file_path =
JoinPath(module_spec_dir, target_file.GetFilename().AsCString());
const auto tmp_file_path = tmp_file.GetPath();
const auto err_code =
llvm::sys::fs::rename(tmp_file_path, module_file_path.GetPath());
if (err_code)
return Status("Failed to rename file %s to %s: %s", tmp_file_path.c_str(),
module_file_path.GetPath().c_str(),
err_code.message().c_str());
const auto error = CreateHostSysRootModuleLink(
root_dir_spec, hostname, target_file, module_file_path, true);
if (error.Fail())
return Status("Failed to create link to %s: %s",
module_file_path.GetPath().c_str(), error.AsCString());
return Status();
}
Status ModuleCache::Get(const FileSpec &root_dir_spec, const char *hostname,
const ModuleSpec &module_spec,
ModuleSP &cached_module_sp, bool *did_create_ptr) {
const auto find_it =
m_loaded_modules.find(module_spec.GetUUID().GetAsString());
if (find_it != m_loaded_modules.end()) {
cached_module_sp = (*find_it).second.lock();
if (cached_module_sp)
return Status();
m_loaded_modules.erase(find_it);
}
const auto module_spec_dir =
GetModuleDirectory(root_dir_spec, module_spec.GetUUID());
const auto module_file_path = JoinPath(
module_spec_dir, module_spec.GetFileSpec().GetFilename().AsCString());
if (!FileSystem::Instance().Exists(module_file_path))
return Status("Module %s not found", module_file_path.GetPath().c_str());
if (FileSystem::Instance().GetByteSize(module_file_path) !=
module_spec.GetObjectSize())
return Status("Module %s has invalid file size",
module_file_path.GetPath().c_str());
// We may have already cached module but downloaded from an another host - in
// this case let's create a link to it.
auto error = CreateHostSysRootModuleLink(root_dir_spec, hostname,
module_spec.GetFileSpec(),
module_file_path, false);
if (error.Fail())
return Status("Failed to create link to %s: %s",
module_file_path.GetPath().c_str(), error.AsCString());
auto cached_module_spec(module_spec);
cached_module_spec.GetUUID().Clear(); // Clear UUID since it may contain md5
// content hash instead of real UUID.
cached_module_spec.GetFileSpec() = module_file_path;
cached_module_spec.GetPlatformFileSpec() = module_spec.GetFileSpec();
error = ModuleList::GetSharedModule(cached_module_spec, cached_module_sp,
nullptr, nullptr, did_create_ptr, false);
if (error.Fail())
return error;
FileSpec symfile_spec = GetSymbolFileSpec(cached_module_sp->GetFileSpec());
if (FileSystem::Instance().Exists(symfile_spec))
cached_module_sp->SetSymbolFileFileSpec(symfile_spec);
m_loaded_modules.insert(
std::make_pair(module_spec.GetUUID().GetAsString(), cached_module_sp));
return Status();
}
Status ModuleCache::GetAndPut(const FileSpec &root_dir_spec,
const char *hostname,
const ModuleSpec &module_spec,
const ModuleDownloader &module_downloader,
const SymfileDownloader &symfile_downloader,
lldb::ModuleSP &cached_module_sp,
bool *did_create_ptr) {
const auto module_spec_dir =
GetModuleDirectory(root_dir_spec, module_spec.GetUUID());
auto error = MakeDirectory(module_spec_dir);
if (error.Fail())
return error;
ModuleLock lock(root_dir_spec, module_spec.GetUUID(), error);
if (error.Fail())
return Status("Failed to lock module %s: %s",
module_spec.GetUUID().GetAsString().c_str(),
error.AsCString());
const auto escaped_hostname(GetEscapedHostname(hostname));
// Check local cache for a module.
error = Get(root_dir_spec, escaped_hostname.c_str(), module_spec,
cached_module_sp, did_create_ptr);
if (error.Success())
return error;
const auto tmp_download_file_spec = JoinPath(module_spec_dir, kTempFileName);
error = module_downloader(module_spec, tmp_download_file_spec);
llvm::FileRemover tmp_file_remover(tmp_download_file_spec.GetPath());
if (error.Fail())
return Status("Failed to download module: %s", error.AsCString());
// Put downloaded file into local module cache.
error = Put(root_dir_spec, escaped_hostname.c_str(), module_spec,
tmp_download_file_spec, module_spec.GetFileSpec());
if (error.Fail())
return Status("Failed to put module into cache: %s", error.AsCString());
tmp_file_remover.releaseFile();
error = Get(root_dir_spec, escaped_hostname.c_str(), module_spec,
cached_module_sp, did_create_ptr);
if (error.Fail())
return error;
// Fetching a symbol file for the module
const auto tmp_download_sym_file_spec =
JoinPath(module_spec_dir, kTempSymFileName);
error = symfile_downloader(cached_module_sp, tmp_download_sym_file_spec);
llvm::FileRemover tmp_symfile_remover(tmp_download_sym_file_spec.GetPath());
if (error.Fail())
// Failed to download a symfile but fetching the module was successful. The
// module might contain the necessary symbols and the debugging is also
// possible without a symfile.
return Status();
error = Put(root_dir_spec, escaped_hostname.c_str(), module_spec,
tmp_download_sym_file_spec,
GetSymbolFileSpec(module_spec.GetFileSpec()));
if (error.Fail())
return Status("Failed to put symbol file into cache: %s",
error.AsCString());
tmp_symfile_remover.releaseFile();
FileSpec symfile_spec = GetSymbolFileSpec(cached_module_sp->GetFileSpec());
cached_module_sp->SetSymbolFileFileSpec(symfile_spec);
return Status();
}
|