1 /*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "common_art_test.h"
18
19 #include <dirent.h>
20 #include <dlfcn.h>
21 #include <fcntl.h>
22 #include <ftw.h>
23 #include <libgen.h>
24 #include <stdlib.h>
25 #include <sys/capability.h>
26 #include <unistd.h>
27
28 #include <cstdio>
29 #include <filesystem>
30 #include <functional>
31
32 #include "android-base/file.h"
33 #include "android-base/logging.h"
34 #include "android-base/process.h"
35 #include "android-base/scopeguard.h"
36 #include "android-base/stringprintf.h"
37 #include "android-base/unique_fd.h"
38 #include "art_field-inl.h"
39 #include "base/file_utils.h"
40 #include "base/logging.h"
41 #include "base/macros.h"
42 #include "base/mem_map.h"
43 #include "base/mutex.h"
44 #include "base/os.h"
45 #include "base/runtime_debug.h"
46 #include "base/scoped_cap.h"
47 #include "base/stl_util.h"
48 #include "base/testing.h"
49 #include "base/unix_file/fd_file.h"
50 #include "dex/art_dex_file_loader.h"
51 #include "dex/dex_file-inl.h"
52 #include "dex/dex_file_loader.h"
53 #include "dex/primitive.h"
54 #include "gtest/gtest.h"
55 #include "nativehelper/scoped_local_ref.h"
56
57 namespace art {
58
59 using android::base::StringPrintf;
60
ScratchDir(bool keep_files)61 ScratchDir::ScratchDir(bool keep_files) : keep_files_(keep_files) {
62 // ANDROID_DATA needs to be set
63 CHECK_NE(static_cast<char*>(nullptr), getenv("ANDROID_DATA")) <<
64 "Are you subclassing RuntimeTest?";
65 path_ = getenv("ANDROID_DATA");
66 path_ += "/tmp-XXXXXX";
67 bool ok = (mkdtemp(&path_[0]) != nullptr);
68 CHECK(ok) << strerror(errno) << " for " << path_;
69 path_ += "/";
70 }
71
~ScratchDir()72 ScratchDir::~ScratchDir() {
73 if (!keep_files_) {
74 std::filesystem::remove_all(path_);
75 }
76 }
77
ScratchFile()78 ScratchFile::ScratchFile() {
79 // ANDROID_DATA needs to be set
80 CHECK_NE(static_cast<char*>(nullptr), getenv("ANDROID_DATA")) <<
81 "Are you subclassing RuntimeTest?";
82 filename_ = getenv("ANDROID_DATA");
83 filename_ += "/TmpFile-XXXXXX";
84 int fd = mkstemp(&filename_[0]);
85 CHECK_NE(-1, fd) << strerror(errno) << " for " << filename_;
86 file_.reset(new File(fd, GetFilename(), true));
87 }
88
ScratchFile(const ScratchFile & other,const char * suffix)89 ScratchFile::ScratchFile(const ScratchFile& other, const char* suffix)
90 : ScratchFile(other.GetFilename() + suffix) {}
91
ScratchFile(const std::string & filename)92 ScratchFile::ScratchFile(const std::string& filename) : filename_(filename) {
93 int fd = open(filename_.c_str(), O_RDWR | O_CREAT | O_CLOEXEC, 0666);
94 CHECK_NE(-1, fd);
95 file_.reset(new File(fd, GetFilename(), true));
96 }
97
ScratchFile(File * file)98 ScratchFile::ScratchFile(File* file) {
99 CHECK(file != nullptr);
100 filename_ = file->GetPath();
101 file_.reset(file);
102 }
103
ScratchFile(ScratchFile && other)104 ScratchFile::ScratchFile(ScratchFile&& other) noexcept {
105 *this = std::move(other);
106 }
107
operator =(ScratchFile && other)108 ScratchFile& ScratchFile::operator=(ScratchFile&& other) noexcept {
109 if (GetFile() != other.GetFile()) {
110 std::swap(filename_, other.filename_);
111 std::swap(file_, other.file_);
112 }
113 return *this;
114 }
115
~ScratchFile()116 ScratchFile::~ScratchFile() {
117 Unlink();
118 }
119
GetFd() const120 int ScratchFile::GetFd() const {
121 return file_->Fd();
122 }
123
Close()124 void ScratchFile::Close() {
125 if (file_ != nullptr) {
126 if (file_->FlushCloseOrErase() != 0) {
127 PLOG(WARNING) << "Error closing scratch file.";
128 }
129 file_.reset();
130 }
131 }
132
Unlink()133 void ScratchFile::Unlink() {
134 if (!OS::FileExists(filename_.c_str())) {
135 return;
136 }
137 Close();
138 int unlink_result = unlink(filename_.c_str());
139 CHECK_EQ(0, unlink_result);
140 }
141
142 // Temporarily drops all root capabilities when the test is run as root. This is a noop otherwise.
ScopedUnroot()143 android::base::ScopeGuard<std::function<void()>> ScopedUnroot() {
144 ScopedCap old_cap(cap_get_proc());
145 CHECK_NE(old_cap.Get(), nullptr);
146 ScopedCap new_cap(cap_dup(old_cap.Get()));
147 CHECK_NE(new_cap.Get(), nullptr);
148 CHECK_EQ(cap_clear_flag(new_cap.Get(), CAP_EFFECTIVE), 0);
149 CHECK_EQ(cap_set_proc(new_cap.Get()), 0);
150 // `old_cap` is actually not shared with anyone else, but we have to wrap it with a `shared_ptr`
151 // because `std::function` requires captures to be copyable.
152 return android::base::make_scope_guard(
153 [old_cap = std::make_shared<ScopedCap>(std::move(old_cap))]() {
154 CHECK_EQ(cap_set_proc(old_cap->Get()), 0);
155 });
156 }
157
158 // Temporarily drops write permission on a file/directory.
ScopedInaccessible(const std::string & path)159 android::base::ScopeGuard<std::function<void()>> ScopedInaccessible(const std::string& path) {
160 std::filesystem::perms old_perms = std::filesystem::status(path).permissions();
161 std::filesystem::permissions(path, std::filesystem::perms::none);
162 return android::base::make_scope_guard([=]() { std::filesystem::permissions(path, old_perms); });
163 }
164
SetUpAndroidRootEnvVars()165 void CommonArtTestImpl::SetUpAndroidRootEnvVars() {
166 if (IsHost()) {
167 std::string android_host_out = GetAndroidHostOut();
168
169 // Environment variable ANDROID_ROOT is set on the device, but not
170 // necessarily on the host.
171 const char* android_root_from_env = getenv("ANDROID_ROOT");
172 if (android_root_from_env == nullptr) {
173 // Use ANDROID_HOST_OUT for ANDROID_ROOT.
174 setenv("ANDROID_ROOT", android_host_out.c_str(), 1);
175 android_root_from_env = getenv("ANDROID_ROOT");
176 }
177
178 // Environment variable ANDROID_I18N_ROOT is set on the device, but not
179 // necessarily on the host. It needs to be set so that various libraries
180 // like libcore / icu4j / icu4c can find their data files.
181 const char* android_i18n_root_from_env = getenv("ANDROID_I18N_ROOT");
182 if (android_i18n_root_from_env == nullptr) {
183 // Use ${ANDROID_I18N_OUT}/com.android.i18n for ANDROID_I18N_ROOT.
184 std::string android_i18n_root = android_host_out;
185 android_i18n_root += "/com.android.i18n";
186 setenv("ANDROID_I18N_ROOT", android_i18n_root.c_str(), 1);
187 }
188
189 // Environment variable ANDROID_ART_ROOT is set on the device, but not
190 // necessarily on the host. It needs to be set so that various libraries
191 // like libcore / icu4j / icu4c can find their data files.
192 const char* android_art_root_from_env = getenv("ANDROID_ART_ROOT");
193 if (android_art_root_from_env == nullptr) {
194 // Use ${ANDROID_HOST_OUT}/com.android.art for ANDROID_ART_ROOT.
195 std::string android_art_root = android_host_out;
196 android_art_root += "/com.android.art";
197 setenv("ANDROID_ART_ROOT", android_art_root.c_str(), 1);
198 }
199
200 // Environment variable ANDROID_TZDATA_ROOT is set on the device, but not
201 // necessarily on the host. It needs to be set so that various libraries
202 // like libcore / icu4j / icu4c can find their data files.
203 const char* android_tzdata_root_from_env = getenv("ANDROID_TZDATA_ROOT");
204 if (android_tzdata_root_from_env == nullptr) {
205 // Use ${ANDROID_HOST_OUT}/com.android.tzdata for ANDROID_TZDATA_ROOT.
206 std::string android_tzdata_root = android_host_out;
207 android_tzdata_root += "/com.android.tzdata";
208 setenv("ANDROID_TZDATA_ROOT", android_tzdata_root.c_str(), 1);
209 }
210
211 setenv("LD_LIBRARY_PATH", ":", 0); // Required by java.lang.System.<clinit>.
212 }
213 }
214
SetUpAndroidDataDir(std::string & android_data)215 void CommonArtTestImpl::SetUpAndroidDataDir(std::string& android_data) {
216 if (IsHost()) {
217 const char* tmpdir = getenv("TMPDIR");
218 if (tmpdir != nullptr && tmpdir[0] != 0) {
219 android_data = tmpdir;
220 } else {
221 android_data = "/tmp";
222 }
223 } else {
224 // On target, we cannot use `/mnt/sdcard` because it is mounted `noexec`,
225 // nor `/data/dalvik-cache` as it is not accessible on `user` builds.
226 // Instead, use `/data/local/tmp`, which does not require any special
227 // permission.
228 android_data = "/data/local/tmp";
229 }
230 android_data += "/art-data-XXXXXX";
231 if (mkdtemp(&android_data[0]) == nullptr) {
232 PLOG(FATAL) << "mkdtemp(\"" << &android_data[0] << "\") failed";
233 }
234 setenv("ANDROID_DATA", android_data.c_str(), 1);
235 }
236
SetUp()237 void CommonArtTestImpl::SetUp() {
238 // Some tests clear these and when running with --no_isolate this can cause
239 // later tests to fail
240 Locks::Init();
241 MemMap::Init();
242 SetUpAndroidRootEnvVars();
243 SetUpAndroidDataDir(android_data_);
244
245 // Re-use the data temporary directory for /system_ext tests
246 android_system_ext_.append(android_data_);
247 android_system_ext_.append("/system_ext");
248 int mkdir_result = mkdir(android_system_ext_.c_str(), 0700);
249 ASSERT_EQ(mkdir_result, 0);
250 setenv("SYSTEM_EXT_ROOT", android_system_ext_.c_str(), 1);
251
252 std::string system_ext_framework = android_system_ext_ + "/framework";
253 mkdir_result = mkdir(system_ext_framework.c_str(), 0700);
254 ASSERT_EQ(mkdir_result, 0);
255
256 dalvik_cache_.append(android_data_);
257 dalvik_cache_.append("/dalvik-cache");
258 mkdir_result = mkdir(dalvik_cache_.c_str(), 0700);
259 ASSERT_EQ(mkdir_result, 0);
260
261 if (kIsDebugBuild) {
262 static bool gSlowDebugTestFlag = false;
263 RegisterRuntimeDebugFlag(&gSlowDebugTestFlag);
264 SetRuntimeDebugFlagsEnabled(true);
265 CHECK(gSlowDebugTestFlag);
266 }
267 }
268
TearDownAndroidDataDir(const std::string & android_data,bool fail_on_error)269 void CommonArtTestImpl::TearDownAndroidDataDir(const std::string& android_data,
270 bool fail_on_error) {
271 if (fail_on_error) {
272 ASSERT_EQ(rmdir(android_data.c_str()), 0);
273 } else {
274 rmdir(android_data.c_str());
275 }
276 }
277
278 // Get prebuilt binary tool.
279 // The paths need to be updated when Android prebuilts update.
GetAndroidTool(const char * name,InstructionSet)280 std::string CommonArtTestImpl::GetAndroidTool(const char* name, InstructionSet) {
281 #ifndef ART_CLANG_PATH
282 UNUSED(name);
283 LOG(FATAL) << "There are no prebuilt tools available.";
284 UNREACHABLE();
285 #else
286 std::string path = GetAndroidBuildTop() + ART_CLANG_PATH + "/bin/";
287 CHECK(OS::DirectoryExists(path.c_str())) << path;
288 path += name;
289 CHECK(OS::FileExists(path.c_str())) << path;
290 return path;
291 #endif
292 }
293
GetCoreArtLocation()294 std::string CommonArtTestImpl::GetCoreArtLocation() {
295 return GetCoreFileLocation("art");
296 }
297
GetCoreOatLocation()298 std::string CommonArtTestImpl::GetCoreOatLocation() {
299 return GetCoreFileLocation("oat");
300 }
301
LoadExpectSingleDexFile(const char * location)302 std::unique_ptr<const DexFile> CommonArtTestImpl::LoadExpectSingleDexFile(const char* location) {
303 std::vector<std::unique_ptr<const DexFile>> dex_files;
304 std::string error_msg;
305 MemMap::Init();
306 static constexpr bool kVerifyChecksum = true;
307 std::string filename(IsHost() ? GetAndroidBuildTop() + location : location);
308 ArtDexFileLoader dex_file_loader(filename.c_str(), std::string(location));
309 if (!dex_file_loader.Open(/* verify= */ true, kVerifyChecksum, &error_msg, &dex_files)) {
310 LOG(FATAL) << "Could not open .dex file '" << filename << "': " << error_msg << "\n";
311 UNREACHABLE();
312 }
313 CHECK_EQ(1U, dex_files.size()) << "Expected only one dex file in " << filename;
314 return std::move(dex_files[0]);
315 }
316
ClearDirectory(const char * dirpath,bool recursive)317 void CommonArtTestImpl::ClearDirectory(const char* dirpath, bool recursive) {
318 CHECK(dirpath != nullptr) << std::string(dirpath);
319 DIR* dir = opendir(dirpath);
320 CHECK(dir != nullptr) << std::string(dirpath);
321 dirent* e;
322 struct stat s;
323 while ((e = readdir(dir)) != nullptr) {
324 if ((strcmp(e->d_name, ".") == 0) || (strcmp(e->d_name, "..") == 0)) {
325 continue;
326 }
327 std::string filename(dirpath);
328 filename.push_back('/');
329 filename.append(e->d_name);
330 int stat_result = lstat(filename.c_str(), &s);
331 ASSERT_EQ(0, stat_result) << "unable to stat " << filename;
332 if (S_ISDIR(s.st_mode)) {
333 if (recursive) {
334 ClearDirectory(filename.c_str());
335 int rmdir_result = rmdir(filename.c_str());
336 ASSERT_EQ(0, rmdir_result) << filename;
337 }
338 } else {
339 int unlink_result = unlink(filename.c_str());
340 ASSERT_EQ(0, unlink_result) << filename;
341 }
342 }
343 closedir(dir);
344 }
345
TearDown()346 void CommonArtTestImpl::TearDown() {
347 const char* android_data = getenv("ANDROID_DATA");
348 ASSERT_TRUE(android_data != nullptr);
349 ClearDirectory(dalvik_cache_.c_str());
350 int rmdir_cache_result = rmdir(dalvik_cache_.c_str());
351 ASSERT_EQ(0, rmdir_cache_result);
352 ClearDirectory(android_system_ext_.c_str(), true);
353 rmdir_cache_result = rmdir(android_system_ext_.c_str());
354 ASSERT_EQ(0, rmdir_cache_result);
355 TearDownAndroidDataDir(android_data_, true);
356 dalvik_cache_.clear();
357 android_system_ext_.clear();
358 }
359
GetLibCoreModuleNames() const360 std::vector<std::string> CommonArtTestImpl::GetLibCoreModuleNames() const {
361 return art::testing::GetLibCoreModuleNames();
362 }
363
364 // Check that for target builds we have ART_TARGET_NATIVETEST_DIR set.
365 #ifdef ART_TARGET
366 #ifndef ART_TARGET_NATIVETEST_DIR
367 #error "ART_TARGET_NATIVETEST_DIR not set."
368 #endif
369 // Wrap it as a string literal.
370 #define ART_TARGET_NATIVETEST_DIR_STRING STRINGIFY(ART_TARGET_NATIVETEST_DIR) "/"
371 #else
372 #define ART_TARGET_NATIVETEST_DIR_STRING ""
373 #endif
374
GetTestDexFileName(const char * name) const375 std::string CommonArtTestImpl::GetTestDexFileName(const char* name) const {
376 CHECK(name != nullptr);
377 // The needed jar files for gtest are located next to the gtest binary itself.
378 std::string executable_dir = android::base::GetExecutableDirectory();
379 for (auto ext : {".jar", ".dex"}) {
380 std::string path = executable_dir + "/art-gtest-jars-" + name + ext;
381 if (OS::FileExists(path.c_str())) {
382 return path;
383 }
384 }
385 LOG(FATAL) << "Test file " << name << " not found";
386 UNREACHABLE();
387 }
388
OpenDexFiles(const char * filename)389 std::vector<std::unique_ptr<const DexFile>> CommonArtTestImpl::OpenDexFiles(const char* filename) {
390 static constexpr bool kVerify = true;
391 static constexpr bool kVerifyChecksum = true;
392 std::string error_msg;
393 ArtDexFileLoader dex_file_loader(filename);
394 std::vector<std::unique_ptr<const DexFile>> dex_files;
395 bool success = dex_file_loader.Open(kVerify, kVerifyChecksum, &error_msg, &dex_files);
396 CHECK(success) << "Failed to open '" << filename << "': " << error_msg;
397 for (auto& dex_file : dex_files) {
398 CHECK(dex_file->IsReadOnly());
399 }
400 return dex_files;
401 }
402
OpenDexFile(const char * filename)403 std::unique_ptr<const DexFile> CommonArtTestImpl::OpenDexFile(const char* filename) {
404 std::vector<std::unique_ptr<const DexFile>> dex_files(OpenDexFiles(filename));
405 CHECK_EQ(dex_files.size(), 1u) << "Expected only one dex file";
406 return std::move(dex_files[0]);
407 }
408
OpenTestDexFiles(const char * name)409 std::vector<std::unique_ptr<const DexFile>> CommonArtTestImpl::OpenTestDexFiles(
410 const char* name) {
411 return OpenDexFiles(GetTestDexFileName(name).c_str());
412 }
413
OpenTestDexFile(const char * name)414 std::unique_ptr<const DexFile> CommonArtTestImpl::OpenTestDexFile(const char* name) {
415 return OpenDexFile(GetTestDexFileName(name).c_str());
416 }
417
GetImageDirectory()418 std::string CommonArtTestImpl::GetImageDirectory() {
419 if (IsHost()) {
420 return GetHostBootClasspathInstallRoot() + "/apex/art_boot_images/javalib";
421 }
422 // On device, the boot image is generated by `generate-boot-image`.
423 // In a standalone test, the boot image is located next to the gtest binary itself.
424 std::string path = android::base::GetExecutableDirectory() + "/art_boot_images";
425 if (OS::DirectoryExists(path.c_str())) {
426 return path;
427 }
428 // In a chroot environment prepared by scripts, the boot image is located in a predefined
429 // location on /system.
430 path = "/system/framework/art_boot_images";
431 if (OS::DirectoryExists(path.c_str())) {
432 return path;
433 }
434 // In art-target-gtest-chroot, the boot image is located in a predefined location on /data because
435 // /system is a mount point that replicates the real one on device.
436 path = "/data/local/tmp/art_boot_images";
437 if (OS::DirectoryExists(path.c_str())) {
438 return path;
439 }
440 LOG(FATAL) << "Boot image not found";
441 UNREACHABLE();
442 }
443
GetCoreFileLocation(const char * suffix)444 std::string CommonArtTestImpl::GetCoreFileLocation(const char* suffix) {
445 CHECK(suffix != nullptr);
446 return GetImageDirectory() + "/boot." + suffix;
447 }
448
CreateClassPath(const std::vector<std::unique_ptr<const DexFile>> & dex_files)449 std::string CommonArtTestImpl::CreateClassPath(
450 const std::vector<std::unique_ptr<const DexFile>>& dex_files) {
451 CHECK(!dex_files.empty());
452 std::string classpath = dex_files[0]->GetLocation();
453 for (size_t i = 1; i < dex_files.size(); i++) {
454 classpath += ":" + dex_files[i]->GetLocation();
455 }
456 return classpath;
457 }
458
CreateClassPathWithChecksums(const std::vector<std::unique_ptr<const DexFile>> & dex_files)459 std::string CommonArtTestImpl::CreateClassPathWithChecksums(
460 const std::vector<std::unique_ptr<const DexFile>>& dex_files) {
461 CHECK(!dex_files.empty());
462 uint32_t checksum = DexFileLoader::GetMultiDexChecksum(dex_files);
463 return dex_files[0]->GetLocation() + "*" + std::to_string(checksum);
464 }
465
ForkAndExec(const std::vector<std::string> & argv,const PostForkFn & post_fork,const OutputHandlerFn & handler)466 CommonArtTestImpl::ForkAndExecResult CommonArtTestImpl::ForkAndExec(
467 const std::vector<std::string>& argv,
468 const PostForkFn& post_fork,
469 const OutputHandlerFn& handler) {
470 ForkAndExecResult result;
471 result.status_code = 0;
472 result.stage = ForkAndExecResult::kLink;
473
474 std::vector<const char*> c_args;
475 c_args.reserve(argv.size() + 1);
476 for (const std::string& str : argv) {
477 c_args.push_back(str.c_str());
478 }
479 c_args.push_back(nullptr);
480
481 android::base::unique_fd link[2];
482 {
483 int link_fd[2];
484
485 if (pipe(link_fd) == -1) {
486 return result;
487 }
488 link[0].reset(link_fd[0]);
489 link[1].reset(link_fd[1]);
490 }
491
492 result.stage = ForkAndExecResult::kFork;
493
494 pid_t pid = fork();
495 if (pid == -1) {
496 return result;
497 }
498
499 // Special return code for failures between fork and exec. Pick something that
500 // the command is unlikely to use.
501 constexpr int kPostForkFailure = 134;
502
503 if (pid == 0) {
504 if (!post_fork()) {
505 LOG(ERROR) << "Failed post-fork function";
506 exit(kPostForkFailure);
507 UNREACHABLE();
508 }
509
510 // Redirect stdout and stderr.
511 dup2(link[1].get(), STDOUT_FILENO);
512 dup2(link[1].get(), STDERR_FILENO);
513
514 link[0].reset();
515 link[1].reset();
516
517 execv(c_args[0], const_cast<char* const*>(c_args.data()));
518 PLOG(ERROR) << "Failed to execv " << c_args[0];
519 exit(kPostForkFailure);
520 UNREACHABLE();
521 }
522
523 result.stage = ForkAndExecResult::kWaitpid;
524 link[1].reset();
525
526 char buffer[128] = { 0 };
527 ssize_t bytes_read = 0;
528 while (TEMP_FAILURE_RETRY(bytes_read = read(link[0].get(), buffer, 128)) > 0) {
529 handler(buffer, bytes_read);
530 }
531 handler(buffer, 0u); // End with a virtual write of zero length to simplify clients.
532
533 link[0].reset();
534
535 if (waitpid(pid, &result.status_code, 0) == -1) {
536 return result;
537 }
538
539 result.stage = ForkAndExecResult::kFinished;
540
541 if (WIFEXITED(result.status_code) && WEXITSTATUS(result.status_code) == kPostForkFailure) {
542 LOG(WARNING) << "ForkAndExec likely failed between fork and exec";
543 }
544
545 return result;
546 }
547
ForkAndExec(const std::vector<std::string> & argv,const PostForkFn & post_fork,std::string * output)548 CommonArtTestImpl::ForkAndExecResult CommonArtTestImpl::ForkAndExec(
549 const std::vector<std::string>& argv, const PostForkFn& post_fork, std::string* output) {
550 auto string_collect_fn = [output](char* buf, size_t len) {
551 *output += std::string(buf, len);
552 };
553 return ForkAndExec(argv, post_fork, string_collect_fn);
554 }
555
GetPidByName(const std::string & process_name)556 std::vector<pid_t> GetPidByName(const std::string& process_name) {
557 std::vector<pid_t> results;
558 for (pid_t pid : android::base::AllPids{}) {
559 std::string cmdline;
560 if (!android::base::ReadFileToString(StringPrintf("/proc/%d/cmdline", pid), &cmdline)) {
561 continue;
562 }
563 // Take the first argument.
564 size_t pos = cmdline.find('\0');
565 if (pos != std::string::npos) {
566 cmdline.resize(pos);
567 }
568 if (cmdline == process_name) {
569 results.push_back(pid);
570 }
571 }
572 return results;
573 }
574
575 } // namespace art
576