1/*
2 * Copyright (C) 2013 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#define _GNU_SOURCE 1
18#include <dirent.h>
19#include <dlfcn.h>
20#include <errno.h>
21#include <fcntl.h>
22#include <inttypes.h>
23#include <pthread.h>
24#include <signal.h>
25#include <stdint.h>
26#include <stdio.h>
27#include <stdlib.h>
28#include <string.h>
29#include <sys/ptrace.h>
30#include <sys/stat.h>
31#include <sys/types.h>
32#include <sys/wait.h>
33#include <time.h>
34#include <unistd.h>
35
36#include <algorithm>
37#include <list>
38#include <memory>
39#include <string>
40#include <vector>
41
42#include <backtrace/Backtrace.h>
43#include <backtrace/BacktraceMap.h>
44
45#include <android-base/stringprintf.h>
46#include <cutils/atomic.h>
47#include <cutils/threads.h>
48
49#include <gtest/gtest.h>
50
51// For the THREAD_SIGNAL definition.
52#include "BacktraceCurrent.h"
53#include "thread_utils.h"
54
55// Number of microseconds per milliseconds.
56#define US_PER_MSEC             1000
57
58// Number of nanoseconds in a second.
59#define NS_PER_SEC              1000000000ULL
60
61// Number of simultaneous dumping operations to perform.
62#define NUM_THREADS  40
63
64// Number of simultaneous threads running in our forked process.
65#define NUM_PTRACE_THREADS 5
66
67struct thread_t {
68  pid_t tid;
69  int32_t state;
70  pthread_t threadId;
71  void* data;
72};
73
74struct dump_thread_t {
75  thread_t thread;
76  Backtrace* backtrace;
77  int32_t* now;
78  int32_t done;
79};
80
81extern "C" {
82// Prototypes for functions in the test library.
83int test_level_one(int, int, int, int, void (*)(void*), void*);
84
85int test_recursive_call(int, void (*)(void*), void*);
86}
87
88uint64_t NanoTime() {
89  struct timespec t = { 0, 0 };
90  clock_gettime(CLOCK_MONOTONIC, &t);
91  return static_cast<uint64_t>(t.tv_sec * NS_PER_SEC + t.tv_nsec);
92}
93
94std::string DumpFrames(Backtrace* backtrace) {
95  if (backtrace->NumFrames() == 0) {
96    return "   No frames to dump.\n";
97  }
98
99  std::string frame;
100  for (size_t i = 0; i < backtrace->NumFrames(); i++) {
101    frame += "   " + backtrace->FormatFrameData(i) + '\n';
102  }
103  return frame;
104}
105
106void WaitForStop(pid_t pid) {
107  uint64_t start = NanoTime();
108
109  siginfo_t si;
110  while (ptrace(PTRACE_GETSIGINFO, pid, 0, &si) < 0 && (errno == EINTR || errno == ESRCH)) {
111    if ((NanoTime() - start) > NS_PER_SEC) {
112      printf("The process did not get to a stopping point in 1 second.\n");
113      break;
114    }
115    usleep(US_PER_MSEC);
116  }
117}
118
119bool ReadyLevelBacktrace(Backtrace* backtrace) {
120  // See if test_level_four is in the backtrace.
121  bool found = false;
122  for (Backtrace::const_iterator it = backtrace->begin(); it != backtrace->end(); ++it) {
123    if (it->func_name == "test_level_four") {
124      found = true;
125      break;
126    }
127  }
128
129  return found;
130}
131
132void VerifyLevelDump(Backtrace* backtrace) {
133  ASSERT_GT(backtrace->NumFrames(), static_cast<size_t>(0))
134    << DumpFrames(backtrace);
135  ASSERT_LT(backtrace->NumFrames(), static_cast<size_t>(MAX_BACKTRACE_FRAMES))
136    << DumpFrames(backtrace);
137
138  // Look through the frames starting at the highest to find the
139  // frame we want.
140  size_t frame_num = 0;
141  for (size_t i = backtrace->NumFrames()-1; i > 2; i--) {
142    if (backtrace->GetFrame(i)->func_name == "test_level_one") {
143      frame_num = i;
144      break;
145    }
146  }
147  ASSERT_LT(static_cast<size_t>(0), frame_num) << DumpFrames(backtrace);
148  ASSERT_LE(static_cast<size_t>(3), frame_num) << DumpFrames(backtrace);
149
150  ASSERT_EQ(backtrace->GetFrame(frame_num)->func_name, "test_level_one")
151    << DumpFrames(backtrace);
152  ASSERT_EQ(backtrace->GetFrame(frame_num-1)->func_name, "test_level_two")
153    << DumpFrames(backtrace);
154  ASSERT_EQ(backtrace->GetFrame(frame_num-2)->func_name, "test_level_three")
155    << DumpFrames(backtrace);
156  ASSERT_EQ(backtrace->GetFrame(frame_num-3)->func_name, "test_level_four")
157    << DumpFrames(backtrace);
158}
159
160void VerifyLevelBacktrace(void*) {
161  std::unique_ptr<Backtrace> backtrace(
162      Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD));
163  ASSERT_TRUE(backtrace.get() != nullptr);
164  ASSERT_TRUE(backtrace->Unwind(0));
165  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
166
167  VerifyLevelDump(backtrace.get());
168}
169
170bool ReadyMaxBacktrace(Backtrace* backtrace) {
171  return (backtrace->NumFrames() == MAX_BACKTRACE_FRAMES);
172}
173
174void VerifyMaxDump(Backtrace* backtrace) {
175  ASSERT_EQ(backtrace->NumFrames(), static_cast<size_t>(MAX_BACKTRACE_FRAMES))
176    << DumpFrames(backtrace);
177  // Verify that the last frame is our recursive call.
178  ASSERT_EQ(backtrace->GetFrame(MAX_BACKTRACE_FRAMES-1)->func_name, "test_recursive_call")
179    << DumpFrames(backtrace);
180}
181
182void VerifyMaxBacktrace(void*) {
183  std::unique_ptr<Backtrace> backtrace(
184      Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD));
185  ASSERT_TRUE(backtrace.get() != nullptr);
186  ASSERT_TRUE(backtrace->Unwind(0));
187  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
188
189  VerifyMaxDump(backtrace.get());
190}
191
192void ThreadSetState(void* data) {
193  thread_t* thread = reinterpret_cast<thread_t*>(data);
194  android_atomic_acquire_store(1, &thread->state);
195  volatile int i = 0;
196  while (thread->state) {
197    i++;
198  }
199}
200
201void VerifyThreadTest(pid_t tid, void (*VerifyFunc)(Backtrace*)) {
202  std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), tid));
203  ASSERT_TRUE(backtrace.get() != nullptr);
204  ASSERT_TRUE(backtrace->Unwind(0));
205  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
206
207  VerifyFunc(backtrace.get());
208}
209
210bool WaitForNonZero(int32_t* value, uint64_t seconds) {
211  uint64_t start = NanoTime();
212  do {
213    if (android_atomic_acquire_load(value)) {
214      return true;
215    }
216  } while ((NanoTime() - start) < seconds * NS_PER_SEC);
217  return false;
218}
219
220TEST(libbacktrace, local_no_unwind_frames) {
221  // Verify that a local unwind does not include any frames within
222  // libunwind or libbacktrace.
223  std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), getpid()));
224  ASSERT_TRUE(backtrace.get() != nullptr);
225  ASSERT_TRUE(backtrace->Unwind(0));
226  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
227
228  ASSERT_TRUE(backtrace->NumFrames() != 0);
229  for (const auto& frame : *backtrace ) {
230    if (BacktraceMap::IsValid(frame.map)) {
231      const std::string name = basename(frame.map.name.c_str());
232      ASSERT_TRUE(name != "libunwind.so" && name != "libbacktrace.so")
233        << DumpFrames(backtrace.get());
234    }
235    break;
236  }
237}
238
239TEST(libbacktrace, local_trace) {
240  ASSERT_NE(test_level_one(1, 2, 3, 4, VerifyLevelBacktrace, nullptr), 0);
241}
242
243void VerifyIgnoreFrames(
244    Backtrace* bt_all, Backtrace* bt_ign1,
245    Backtrace* bt_ign2, const char* cur_proc) {
246  EXPECT_EQ(bt_all->NumFrames(), bt_ign1->NumFrames() + 1)
247    << "All backtrace:\n" << DumpFrames(bt_all) << "Ignore 1 backtrace:\n" << DumpFrames(bt_ign1);
248  EXPECT_EQ(bt_all->NumFrames(), bt_ign2->NumFrames() + 2)
249    << "All backtrace:\n" << DumpFrames(bt_all) << "Ignore 2 backtrace:\n" << DumpFrames(bt_ign2);
250
251  // Check all of the frames are the same > the current frame.
252  bool check = (cur_proc == nullptr);
253  for (size_t i = 0; i < bt_ign2->NumFrames(); i++) {
254    if (check) {
255      EXPECT_EQ(bt_ign2->GetFrame(i)->pc, bt_ign1->GetFrame(i+1)->pc);
256      EXPECT_EQ(bt_ign2->GetFrame(i)->sp, bt_ign1->GetFrame(i+1)->sp);
257      EXPECT_EQ(bt_ign2->GetFrame(i)->stack_size, bt_ign1->GetFrame(i+1)->stack_size);
258
259      EXPECT_EQ(bt_ign2->GetFrame(i)->pc, bt_all->GetFrame(i+2)->pc);
260      EXPECT_EQ(bt_ign2->GetFrame(i)->sp, bt_all->GetFrame(i+2)->sp);
261      EXPECT_EQ(bt_ign2->GetFrame(i)->stack_size, bt_all->GetFrame(i+2)->stack_size);
262    }
263    if (!check && bt_ign2->GetFrame(i)->func_name == cur_proc) {
264      check = true;
265    }
266  }
267}
268
269void VerifyLevelIgnoreFrames(void*) {
270  std::unique_ptr<Backtrace> all(
271      Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD));
272  ASSERT_TRUE(all.get() != nullptr);
273  ASSERT_TRUE(all->Unwind(0));
274  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, all->GetError());
275
276  std::unique_ptr<Backtrace> ign1(
277      Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD));
278  ASSERT_TRUE(ign1.get() != nullptr);
279  ASSERT_TRUE(ign1->Unwind(1));
280  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, ign1->GetError());
281
282  std::unique_ptr<Backtrace> ign2(
283      Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD));
284  ASSERT_TRUE(ign2.get() != nullptr);
285  ASSERT_TRUE(ign2->Unwind(2));
286  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, ign2->GetError());
287
288  VerifyIgnoreFrames(all.get(), ign1.get(), ign2.get(), "VerifyLevelIgnoreFrames");
289}
290
291TEST(libbacktrace, local_trace_ignore_frames) {
292  ASSERT_NE(test_level_one(1, 2, 3, 4, VerifyLevelIgnoreFrames, nullptr), 0);
293}
294
295TEST(libbacktrace, local_max_trace) {
296  ASSERT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, VerifyMaxBacktrace, nullptr), 0);
297}
298
299void VerifyProcTest(pid_t pid, pid_t tid, bool share_map,
300                    bool (*ReadyFunc)(Backtrace*),
301                    void (*VerifyFunc)(Backtrace*)) {
302  pid_t ptrace_tid;
303  if (tid < 0) {
304    ptrace_tid = pid;
305  } else {
306    ptrace_tid = tid;
307  }
308  uint64_t start = NanoTime();
309  bool verified = false;
310  std::string last_dump;
311  do {
312    usleep(US_PER_MSEC);
313    if (ptrace(PTRACE_ATTACH, ptrace_tid, 0, 0) == 0) {
314      // Wait for the process to get to a stopping point.
315      WaitForStop(ptrace_tid);
316
317      std::unique_ptr<BacktraceMap> map;
318      if (share_map) {
319        map.reset(BacktraceMap::Create(pid));
320      }
321      std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, tid, map.get()));
322      ASSERT_TRUE(backtrace.get() != nullptr);
323      ASSERT_TRUE(backtrace->Unwind(0));
324      ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
325      if (ReadyFunc(backtrace.get())) {
326        VerifyFunc(backtrace.get());
327        verified = true;
328      } else {
329        last_dump = DumpFrames(backtrace.get());
330      }
331
332      ASSERT_TRUE(ptrace(PTRACE_DETACH, ptrace_tid, 0, 0) == 0);
333    }
334    // If 5 seconds have passed, then we are done.
335  } while (!verified && (NanoTime() - start) <= 5 * NS_PER_SEC);
336  ASSERT_TRUE(verified) << "Last backtrace:\n" << last_dump;
337}
338
339TEST(libbacktrace, ptrace_trace) {
340  pid_t pid;
341  if ((pid = fork()) == 0) {
342    ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0);
343    _exit(1);
344  }
345  VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, false, ReadyLevelBacktrace, VerifyLevelDump);
346
347  kill(pid, SIGKILL);
348  int status;
349  ASSERT_EQ(waitpid(pid, &status, 0), pid);
350}
351
352TEST(libbacktrace, ptrace_trace_shared_map) {
353  pid_t pid;
354  if ((pid = fork()) == 0) {
355    ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0);
356    _exit(1);
357  }
358
359  VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, true, ReadyLevelBacktrace, VerifyLevelDump);
360
361  kill(pid, SIGKILL);
362  int status;
363  ASSERT_EQ(waitpid(pid, &status, 0), pid);
364}
365
366TEST(libbacktrace, ptrace_max_trace) {
367  pid_t pid;
368  if ((pid = fork()) == 0) {
369    ASSERT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, nullptr, nullptr), 0);
370    _exit(1);
371  }
372  VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, false, ReadyMaxBacktrace, VerifyMaxDump);
373
374  kill(pid, SIGKILL);
375  int status;
376  ASSERT_EQ(waitpid(pid, &status, 0), pid);
377}
378
379void VerifyProcessIgnoreFrames(Backtrace* bt_all) {
380  std::unique_ptr<Backtrace> ign1(Backtrace::Create(bt_all->Pid(), BACKTRACE_CURRENT_THREAD));
381  ASSERT_TRUE(ign1.get() != nullptr);
382  ASSERT_TRUE(ign1->Unwind(1));
383  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, ign1->GetError());
384
385  std::unique_ptr<Backtrace> ign2(Backtrace::Create(bt_all->Pid(), BACKTRACE_CURRENT_THREAD));
386  ASSERT_TRUE(ign2.get() != nullptr);
387  ASSERT_TRUE(ign2->Unwind(2));
388  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, ign2->GetError());
389
390  VerifyIgnoreFrames(bt_all, ign1.get(), ign2.get(), nullptr);
391}
392
393TEST(libbacktrace, ptrace_ignore_frames) {
394  pid_t pid;
395  if ((pid = fork()) == 0) {
396    ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0);
397    _exit(1);
398  }
399  VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, false, ReadyLevelBacktrace, VerifyProcessIgnoreFrames);
400
401  kill(pid, SIGKILL);
402  int status;
403  ASSERT_EQ(waitpid(pid, &status, 0), pid);
404}
405
406// Create a process with multiple threads and dump all of the threads.
407void* PtraceThreadLevelRun(void*) {
408  EXPECT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0);
409  return nullptr;
410}
411
412void GetThreads(pid_t pid, std::vector<pid_t>* threads) {
413  // Get the list of tasks.
414  char task_path[128];
415  snprintf(task_path, sizeof(task_path), "/proc/%d/task", pid);
416
417  DIR* tasks_dir = opendir(task_path);
418  ASSERT_TRUE(tasks_dir != nullptr);
419  struct dirent* entry;
420  while ((entry = readdir(tasks_dir)) != nullptr) {
421    char* end;
422    pid_t tid = strtoul(entry->d_name, &end, 10);
423    if (*end == '\0') {
424      threads->push_back(tid);
425    }
426  }
427  closedir(tasks_dir);
428}
429
430TEST(libbacktrace, ptrace_threads) {
431  pid_t pid;
432  if ((pid = fork()) == 0) {
433    for (size_t i = 0; i < NUM_PTRACE_THREADS; i++) {
434      pthread_attr_t attr;
435      pthread_attr_init(&attr);
436      pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
437
438      pthread_t thread;
439      ASSERT_TRUE(pthread_create(&thread, &attr, PtraceThreadLevelRun, nullptr) == 0);
440    }
441    ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0);
442    _exit(1);
443  }
444
445  // Check to see that all of the threads are running before unwinding.
446  std::vector<pid_t> threads;
447  uint64_t start = NanoTime();
448  do {
449    usleep(US_PER_MSEC);
450    threads.clear();
451    GetThreads(pid, &threads);
452  } while ((threads.size() != NUM_PTRACE_THREADS + 1) &&
453      ((NanoTime() - start) <= 5 * NS_PER_SEC));
454  ASSERT_EQ(threads.size(), static_cast<size_t>(NUM_PTRACE_THREADS + 1));
455
456  ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0);
457  WaitForStop(pid);
458  for (std::vector<int>::const_iterator it = threads.begin(); it != threads.end(); ++it) {
459    // Skip the current forked process, we only care about the threads.
460    if (pid == *it) {
461      continue;
462    }
463    VerifyProcTest(pid, *it, false, ReadyLevelBacktrace, VerifyLevelDump);
464  }
465  ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0);
466
467  kill(pid, SIGKILL);
468  int status;
469  ASSERT_EQ(waitpid(pid, &status, 0), pid);
470}
471
472void VerifyLevelThread(void*) {
473  std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), gettid()));
474  ASSERT_TRUE(backtrace.get() != nullptr);
475  ASSERT_TRUE(backtrace->Unwind(0));
476  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
477
478  VerifyLevelDump(backtrace.get());
479}
480
481TEST(libbacktrace, thread_current_level) {
482  ASSERT_NE(test_level_one(1, 2, 3, 4, VerifyLevelThread, nullptr), 0);
483}
484
485void VerifyMaxThread(void*) {
486  std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), gettid()));
487  ASSERT_TRUE(backtrace.get() != nullptr);
488  ASSERT_TRUE(backtrace->Unwind(0));
489  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
490
491  VerifyMaxDump(backtrace.get());
492}
493
494TEST(libbacktrace, thread_current_max) {
495  ASSERT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, VerifyMaxThread, nullptr), 0);
496}
497
498void* ThreadLevelRun(void* data) {
499  thread_t* thread = reinterpret_cast<thread_t*>(data);
500
501  thread->tid = gettid();
502  EXPECT_NE(test_level_one(1, 2, 3, 4, ThreadSetState, data), 0);
503  return nullptr;
504}
505
506TEST(libbacktrace, thread_level_trace) {
507  pthread_attr_t attr;
508  pthread_attr_init(&attr);
509  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
510
511  thread_t thread_data = { 0, 0, 0, nullptr };
512  pthread_t thread;
513  ASSERT_TRUE(pthread_create(&thread, &attr, ThreadLevelRun, &thread_data) == 0);
514
515  // Wait up to 2 seconds for the tid to be set.
516  ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2));
517
518  // Make sure that the thread signal used is not visible when compiled for
519  // the target.
520#if !defined(__GLIBC__)
521  ASSERT_LT(THREAD_SIGNAL, SIGRTMIN);
522#endif
523
524  // Save the current signal action and make sure it is restored afterwards.
525  struct sigaction cur_action;
526  ASSERT_TRUE(sigaction(THREAD_SIGNAL, nullptr, &cur_action) == 0);
527
528  std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), thread_data.tid));
529  ASSERT_TRUE(backtrace.get() != nullptr);
530  ASSERT_TRUE(backtrace->Unwind(0));
531  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
532
533  VerifyLevelDump(backtrace.get());
534
535  // Tell the thread to exit its infinite loop.
536  android_atomic_acquire_store(0, &thread_data.state);
537
538  // Verify that the old action was restored.
539  struct sigaction new_action;
540  ASSERT_TRUE(sigaction(THREAD_SIGNAL, nullptr, &new_action) == 0);
541  EXPECT_EQ(cur_action.sa_sigaction, new_action.sa_sigaction);
542  // The SA_RESTORER flag gets set behind our back, so a direct comparison
543  // doesn't work unless we mask the value off. Mips doesn't have this
544  // flag, so skip this on that platform.
545#if defined(SA_RESTORER)
546  cur_action.sa_flags &= ~SA_RESTORER;
547  new_action.sa_flags &= ~SA_RESTORER;
548#elif defined(__GLIBC__)
549  // Our host compiler doesn't appear to define this flag for some reason.
550  cur_action.sa_flags &= ~0x04000000;
551  new_action.sa_flags &= ~0x04000000;
552#endif
553  EXPECT_EQ(cur_action.sa_flags, new_action.sa_flags);
554}
555
556TEST(libbacktrace, thread_ignore_frames) {
557  pthread_attr_t attr;
558  pthread_attr_init(&attr);
559  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
560
561  thread_t thread_data = { 0, 0, 0, nullptr };
562  pthread_t thread;
563  ASSERT_TRUE(pthread_create(&thread, &attr, ThreadLevelRun, &thread_data) == 0);
564
565  // Wait up to 2 seconds for the tid to be set.
566  ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2));
567
568  std::unique_ptr<Backtrace> all(Backtrace::Create(getpid(), thread_data.tid));
569  ASSERT_TRUE(all.get() != nullptr);
570  ASSERT_TRUE(all->Unwind(0));
571  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, all->GetError());
572
573  std::unique_ptr<Backtrace> ign1(Backtrace::Create(getpid(), thread_data.tid));
574  ASSERT_TRUE(ign1.get() != nullptr);
575  ASSERT_TRUE(ign1->Unwind(1));
576  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, ign1->GetError());
577
578  std::unique_ptr<Backtrace> ign2(Backtrace::Create(getpid(), thread_data.tid));
579  ASSERT_TRUE(ign2.get() != nullptr);
580  ASSERT_TRUE(ign2->Unwind(2));
581  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, ign2->GetError());
582
583  VerifyIgnoreFrames(all.get(), ign1.get(), ign2.get(), nullptr);
584
585  // Tell the thread to exit its infinite loop.
586  android_atomic_acquire_store(0, &thread_data.state);
587}
588
589void* ThreadMaxRun(void* data) {
590  thread_t* thread = reinterpret_cast<thread_t*>(data);
591
592  thread->tid = gettid();
593  EXPECT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, ThreadSetState, data), 0);
594  return nullptr;
595}
596
597TEST(libbacktrace, thread_max_trace) {
598  pthread_attr_t attr;
599  pthread_attr_init(&attr);
600  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
601
602  thread_t thread_data = { 0, 0, 0, nullptr };
603  pthread_t thread;
604  ASSERT_TRUE(pthread_create(&thread, &attr, ThreadMaxRun, &thread_data) == 0);
605
606  // Wait for the tid to be set.
607  ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2));
608
609  std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), thread_data.tid));
610  ASSERT_TRUE(backtrace.get() != nullptr);
611  ASSERT_TRUE(backtrace->Unwind(0));
612  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
613
614  VerifyMaxDump(backtrace.get());
615
616  // Tell the thread to exit its infinite loop.
617  android_atomic_acquire_store(0, &thread_data.state);
618}
619
620void* ThreadDump(void* data) {
621  dump_thread_t* dump = reinterpret_cast<dump_thread_t*>(data);
622  while (true) {
623    if (android_atomic_acquire_load(dump->now)) {
624      break;
625    }
626  }
627
628  // The status of the actual unwind will be checked elsewhere.
629  dump->backtrace = Backtrace::Create(getpid(), dump->thread.tid);
630  dump->backtrace->Unwind(0);
631
632  android_atomic_acquire_store(1, &dump->done);
633
634  return nullptr;
635}
636
637TEST(libbacktrace, thread_multiple_dump) {
638  // Dump NUM_THREADS simultaneously.
639  std::vector<thread_t> runners(NUM_THREADS);
640  std::vector<dump_thread_t> dumpers(NUM_THREADS);
641
642  pthread_attr_t attr;
643  pthread_attr_init(&attr);
644  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
645  for (size_t i = 0; i < NUM_THREADS; i++) {
646    // Launch the runners, they will spin in hard loops doing nothing.
647    runners[i].tid = 0;
648    runners[i].state = 0;
649    ASSERT_TRUE(pthread_create(&runners[i].threadId, &attr, ThreadMaxRun, &runners[i]) == 0);
650  }
651
652  // Wait for tids to be set.
653  for (std::vector<thread_t>::iterator it = runners.begin(); it != runners.end(); ++it) {
654    ASSERT_TRUE(WaitForNonZero(&it->state, 30));
655  }
656
657  // Start all of the dumpers at once, they will spin until they are signalled
658  // to begin their dump run.
659  int32_t dump_now = 0;
660  for (size_t i = 0; i < NUM_THREADS; i++) {
661    dumpers[i].thread.tid = runners[i].tid;
662    dumpers[i].thread.state = 0;
663    dumpers[i].done = 0;
664    dumpers[i].now = &dump_now;
665
666    ASSERT_TRUE(pthread_create(&dumpers[i].thread.threadId, &attr, ThreadDump, &dumpers[i]) == 0);
667  }
668
669  // Start all of the dumpers going at once.
670  android_atomic_acquire_store(1, &dump_now);
671
672  for (size_t i = 0; i < NUM_THREADS; i++) {
673    ASSERT_TRUE(WaitForNonZero(&dumpers[i].done, 30));
674
675    // Tell the runner thread to exit its infinite loop.
676    android_atomic_acquire_store(0, &runners[i].state);
677
678    ASSERT_TRUE(dumpers[i].backtrace != nullptr);
679    VerifyMaxDump(dumpers[i].backtrace);
680
681    delete dumpers[i].backtrace;
682    dumpers[i].backtrace = nullptr;
683  }
684}
685
686TEST(libbacktrace, thread_multiple_dump_same_thread) {
687  pthread_attr_t attr;
688  pthread_attr_init(&attr);
689  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
690  thread_t runner;
691  runner.tid = 0;
692  runner.state = 0;
693  ASSERT_TRUE(pthread_create(&runner.threadId, &attr, ThreadMaxRun, &runner) == 0);
694
695  // Wait for tids to be set.
696  ASSERT_TRUE(WaitForNonZero(&runner.state, 30));
697
698  // Start all of the dumpers at once, they will spin until they are signalled
699  // to begin their dump run.
700  int32_t dump_now = 0;
701  // Dump the same thread NUM_THREADS simultaneously.
702  std::vector<dump_thread_t> dumpers(NUM_THREADS);
703  for (size_t i = 0; i < NUM_THREADS; i++) {
704    dumpers[i].thread.tid = runner.tid;
705    dumpers[i].thread.state = 0;
706    dumpers[i].done = 0;
707    dumpers[i].now = &dump_now;
708
709    ASSERT_TRUE(pthread_create(&dumpers[i].thread.threadId, &attr, ThreadDump, &dumpers[i]) == 0);
710  }
711
712  // Start all of the dumpers going at once.
713  android_atomic_acquire_store(1, &dump_now);
714
715  for (size_t i = 0; i < NUM_THREADS; i++) {
716    ASSERT_TRUE(WaitForNonZero(&dumpers[i].done, 30));
717
718    ASSERT_TRUE(dumpers[i].backtrace != nullptr);
719    VerifyMaxDump(dumpers[i].backtrace);
720
721    delete dumpers[i].backtrace;
722    dumpers[i].backtrace = nullptr;
723  }
724
725  // Tell the runner thread to exit its infinite loop.
726  android_atomic_acquire_store(0, &runner.state);
727}
728
729// This test is for UnwindMaps that should share the same map cursor when
730// multiple maps are created for the current process at the same time.
731TEST(libbacktrace, simultaneous_maps) {
732  BacktraceMap* map1 = BacktraceMap::Create(getpid());
733  BacktraceMap* map2 = BacktraceMap::Create(getpid());
734  BacktraceMap* map3 = BacktraceMap::Create(getpid());
735
736  Backtrace* back1 = Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD, map1);
737  ASSERT_TRUE(back1 != nullptr);
738  EXPECT_TRUE(back1->Unwind(0));
739  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, back1->GetError());
740  delete back1;
741  delete map1;
742
743  Backtrace* back2 = Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD, map2);
744  ASSERT_TRUE(back2 != nullptr);
745  EXPECT_TRUE(back2->Unwind(0));
746  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, back2->GetError());
747  delete back2;
748  delete map2;
749
750  Backtrace* back3 = Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD, map3);
751  ASSERT_TRUE(back3 != nullptr);
752  EXPECT_TRUE(back3->Unwind(0));
753  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, back3->GetError());
754  delete back3;
755  delete map3;
756}
757
758TEST(libbacktrace, fillin_erases) {
759  BacktraceMap* back_map = BacktraceMap::Create(getpid());
760
761  backtrace_map_t map;
762
763  map.start = 1;
764  map.end = 3;
765  map.flags = 1;
766  map.name = "Initialized";
767  back_map->FillIn(0, &map);
768  delete back_map;
769
770  ASSERT_FALSE(BacktraceMap::IsValid(map));
771  ASSERT_EQ(static_cast<uintptr_t>(0), map.start);
772  ASSERT_EQ(static_cast<uintptr_t>(0), map.end);
773  ASSERT_EQ(0, map.flags);
774  ASSERT_EQ("", map.name);
775}
776
777TEST(libbacktrace, format_test) {
778  std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD));
779  ASSERT_TRUE(backtrace.get() != nullptr);
780
781  backtrace_frame_data_t frame;
782  frame.num = 1;
783  frame.pc = 2;
784  frame.sp = 0;
785  frame.stack_size = 0;
786  frame.func_offset = 0;
787
788  // Check no map set.
789  frame.num = 1;
790#if defined(__LP64__)
791  EXPECT_EQ("#01 pc 0000000000000002  <unknown>",
792#else
793  EXPECT_EQ("#01 pc 00000002  <unknown>",
794#endif
795            backtrace->FormatFrameData(&frame));
796
797  // Check map name empty, but exists.
798  frame.pc = 0xb0020;
799  frame.map.start = 0xb0000;
800  frame.map.end = 0xbffff;
801  frame.map.load_base = 0;
802#if defined(__LP64__)
803  EXPECT_EQ("#01 pc 0000000000000020  <anonymous:00000000000b0000>",
804#else
805  EXPECT_EQ("#01 pc 00000020  <anonymous:000b0000>",
806#endif
807            backtrace->FormatFrameData(&frame));
808
809  // Check map name begins with a [.
810  frame.pc = 0xc0020;
811  frame.map.start = 0xc0000;
812  frame.map.end = 0xcffff;
813  frame.map.load_base = 0;
814  frame.map.name = "[anon:thread signal stack]";
815#if defined(__LP64__)
816  EXPECT_EQ("#01 pc 0000000000000020  [anon:thread signal stack:00000000000c0000]",
817#else
818  EXPECT_EQ("#01 pc 00000020  [anon:thread signal stack:000c0000]",
819#endif
820            backtrace->FormatFrameData(&frame));
821
822  // Check relative pc is set and map name is set.
823  frame.pc = 0x12345679;
824  frame.map.name = "MapFake";
825  frame.map.start =  1;
826  frame.map.end =  1;
827#if defined(__LP64__)
828  EXPECT_EQ("#01 pc 0000000012345678  MapFake",
829#else
830  EXPECT_EQ("#01 pc 12345678  MapFake",
831#endif
832            backtrace->FormatFrameData(&frame));
833
834  // Check func_name is set, but no func offset.
835  frame.func_name = "ProcFake";
836#if defined(__LP64__)
837  EXPECT_EQ("#01 pc 0000000012345678  MapFake (ProcFake)",
838#else
839  EXPECT_EQ("#01 pc 12345678  MapFake (ProcFake)",
840#endif
841            backtrace->FormatFrameData(&frame));
842
843  // Check func_name is set, and func offset is non-zero.
844  frame.func_offset = 645;
845#if defined(__LP64__)
846  EXPECT_EQ("#01 pc 0000000012345678  MapFake (ProcFake+645)",
847#else
848  EXPECT_EQ("#01 pc 12345678  MapFake (ProcFake+645)",
849#endif
850            backtrace->FormatFrameData(&frame));
851
852  // Check func_name is set, func offset is non-zero, and load_base is non-zero.
853  frame.func_offset = 645;
854  frame.map.load_base = 100;
855#if defined(__LP64__)
856  EXPECT_EQ("#01 pc 00000000123456dc  MapFake (ProcFake+645)",
857#else
858  EXPECT_EQ("#01 pc 123456dc  MapFake (ProcFake+645)",
859#endif
860            backtrace->FormatFrameData(&frame));
861
862  // Check a non-zero map offset.
863  frame.map.offset = 0x1000;
864#if defined(__LP64__)
865  EXPECT_EQ("#01 pc 00000000123456dc  MapFake (offset 0x1000) (ProcFake+645)",
866#else
867  EXPECT_EQ("#01 pc 123456dc  MapFake (offset 0x1000) (ProcFake+645)",
868#endif
869            backtrace->FormatFrameData(&frame));
870}
871
872struct map_test_t {
873  uintptr_t start;
874  uintptr_t end;
875};
876
877bool map_sort(map_test_t i, map_test_t j) {
878  return i.start < j.start;
879}
880
881void VerifyMap(pid_t pid) {
882  char buffer[4096];
883  snprintf(buffer, sizeof(buffer), "/proc/%d/maps", pid);
884
885  FILE* map_file = fopen(buffer, "r");
886  ASSERT_TRUE(map_file != nullptr);
887  std::vector<map_test_t> test_maps;
888  while (fgets(buffer, sizeof(buffer), map_file)) {
889    map_test_t map;
890    ASSERT_EQ(2, sscanf(buffer, "%" SCNxPTR "-%" SCNxPTR " ", &map.start, &map.end));
891    test_maps.push_back(map);
892  }
893  fclose(map_file);
894  std::sort(test_maps.begin(), test_maps.end(), map_sort);
895
896  std::unique_ptr<BacktraceMap> map(BacktraceMap::Create(pid));
897
898  // Basic test that verifies that the map is in the expected order.
899  std::vector<map_test_t>::const_iterator test_it = test_maps.begin();
900  for (BacktraceMap::const_iterator it = map->begin(); it != map->end(); ++it) {
901    ASSERT_TRUE(test_it != test_maps.end());
902    ASSERT_EQ(test_it->start, it->start);
903    ASSERT_EQ(test_it->end, it->end);
904    ++test_it;
905  }
906  ASSERT_TRUE(test_it == test_maps.end());
907}
908
909TEST(libbacktrace, verify_map_remote) {
910  pid_t pid;
911
912  if ((pid = fork()) == 0) {
913    while (true) {
914    }
915    _exit(0);
916  }
917  ASSERT_LT(0, pid);
918
919  ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0);
920
921  // Wait for the process to get to a stopping point.
922  WaitForStop(pid);
923
924  // The maps should match exactly since the forked process has been paused.
925  VerifyMap(pid);
926
927  ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0);
928
929  kill(pid, SIGKILL);
930  ASSERT_EQ(waitpid(pid, nullptr, 0), pid);
931}
932
933void InitMemory(uint8_t* memory, size_t bytes) {
934  for (size_t i = 0; i < bytes; i++) {
935    memory[i] = i;
936    if (memory[i] == '\0') {
937      // Don't use '\0' in our data so we can verify that an overread doesn't
938      // occur by using a '\0' as the character after the read data.
939      memory[i] = 23;
940    }
941  }
942}
943
944void* ThreadReadTest(void* data) {
945  thread_t* thread_data = reinterpret_cast<thread_t*>(data);
946
947  thread_data->tid = gettid();
948
949  // Create two map pages.
950  // Mark the second page as not-readable.
951  size_t pagesize = static_cast<size_t>(sysconf(_SC_PAGE_SIZE));
952  uint8_t* memory;
953  if (posix_memalign(reinterpret_cast<void**>(&memory), pagesize, 2 * pagesize) != 0) {
954    return reinterpret_cast<void*>(-1);
955  }
956
957  if (mprotect(&memory[pagesize], pagesize, PROT_NONE) != 0) {
958    return reinterpret_cast<void*>(-1);
959  }
960
961  // Set up a simple pattern in memory.
962  InitMemory(memory, pagesize);
963
964  thread_data->data = memory;
965
966  // Tell the caller it's okay to start reading memory.
967  android_atomic_acquire_store(1, &thread_data->state);
968
969  // Loop waiting for the caller to finish reading the memory.
970  while (thread_data->state) {
971  }
972
973  // Re-enable read-write on the page so that we don't crash if we try
974  // and access data on this page when freeing the memory.
975  if (mprotect(&memory[pagesize], pagesize, PROT_READ | PROT_WRITE) != 0) {
976    return reinterpret_cast<void*>(-1);
977  }
978  free(memory);
979
980  android_atomic_acquire_store(1, &thread_data->state);
981
982  return nullptr;
983}
984
985void RunReadTest(Backtrace* backtrace, uintptr_t read_addr) {
986  size_t pagesize = static_cast<size_t>(sysconf(_SC_PAGE_SIZE));
987
988  // Create a page of data to use to do quick compares.
989  uint8_t* expected = new uint8_t[pagesize];
990  InitMemory(expected, pagesize);
991
992  uint8_t* data = new uint8_t[2*pagesize];
993  // Verify that we can only read one page worth of data.
994  size_t bytes_read = backtrace->Read(read_addr, data, 2 * pagesize);
995  ASSERT_EQ(pagesize, bytes_read);
996  ASSERT_TRUE(memcmp(data, expected, pagesize) == 0);
997
998  // Verify unaligned reads.
999  for (size_t i = 1; i < sizeof(word_t); i++) {
1000    bytes_read = backtrace->Read(read_addr + i, data, 2 * sizeof(word_t));
1001    ASSERT_EQ(2 * sizeof(word_t), bytes_read);
1002    ASSERT_TRUE(memcmp(data, &expected[i], 2 * sizeof(word_t)) == 0)
1003        << "Offset at " << i << " failed";
1004  }
1005
1006  // Verify small unaligned reads.
1007  for (size_t i = 1; i < sizeof(word_t); i++) {
1008    for (size_t j = 1; j < sizeof(word_t); j++) {
1009      // Set one byte past what we expect to read, to guarantee we don't overread.
1010      data[j] = '\0';
1011      bytes_read = backtrace->Read(read_addr + i, data, j);
1012      ASSERT_EQ(j, bytes_read);
1013      ASSERT_TRUE(memcmp(data, &expected[i], j) == 0)
1014          << "Offset at " << i << " length " << j << " miscompared";
1015      ASSERT_EQ('\0', data[j])
1016          << "Offset at " << i << " length " << j << " wrote too much data";
1017    }
1018  }
1019  delete[] data;
1020  delete[] expected;
1021}
1022
1023TEST(libbacktrace, thread_read) {
1024  pthread_attr_t attr;
1025  pthread_attr_init(&attr);
1026  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
1027  pthread_t thread;
1028  thread_t thread_data = { 0, 0, 0, nullptr };
1029  ASSERT_TRUE(pthread_create(&thread, &attr, ThreadReadTest, &thread_data) == 0);
1030
1031  ASSERT_TRUE(WaitForNonZero(&thread_data.state, 10));
1032
1033  std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), thread_data.tid));
1034  ASSERT_TRUE(backtrace.get() != nullptr);
1035
1036  RunReadTest(backtrace.get(), reinterpret_cast<uintptr_t>(thread_data.data));
1037
1038  android_atomic_acquire_store(0, &thread_data.state);
1039
1040  ASSERT_TRUE(WaitForNonZero(&thread_data.state, 10));
1041}
1042
1043volatile uintptr_t g_ready = 0;
1044volatile uintptr_t g_addr = 0;
1045
1046void ForkedReadTest() {
1047  // Create two map pages.
1048  size_t pagesize = static_cast<size_t>(sysconf(_SC_PAGE_SIZE));
1049  uint8_t* memory;
1050  if (posix_memalign(reinterpret_cast<void**>(&memory), pagesize, 2 * pagesize) != 0) {
1051    perror("Failed to allocate memory\n");
1052    exit(1);
1053  }
1054
1055  // Mark the second page as not-readable.
1056  if (mprotect(&memory[pagesize], pagesize, PROT_NONE) != 0) {
1057    perror("Failed to mprotect memory\n");
1058    exit(1);
1059  }
1060
1061  // Set up a simple pattern in memory.
1062  InitMemory(memory, pagesize);
1063
1064  g_addr = reinterpret_cast<uintptr_t>(memory);
1065  g_ready = 1;
1066
1067  while (1) {
1068    usleep(US_PER_MSEC);
1069  }
1070}
1071
1072TEST(libbacktrace, process_read) {
1073  g_ready = 0;
1074  pid_t pid;
1075  if ((pid = fork()) == 0) {
1076    ForkedReadTest();
1077    exit(0);
1078  }
1079  ASSERT_NE(-1, pid);
1080
1081  bool test_executed = false;
1082  uint64_t start = NanoTime();
1083  while (1) {
1084    if (ptrace(PTRACE_ATTACH, pid, 0, 0) == 0) {
1085      WaitForStop(pid);
1086
1087      std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, pid));
1088      ASSERT_TRUE(backtrace.get() != nullptr);
1089
1090      uintptr_t read_addr;
1091      size_t bytes_read = backtrace->Read(reinterpret_cast<uintptr_t>(&g_ready),
1092                                          reinterpret_cast<uint8_t*>(&read_addr),
1093                                          sizeof(uintptr_t));
1094      ASSERT_EQ(sizeof(uintptr_t), bytes_read);
1095      if (read_addr) {
1096        // The forked process is ready to be read.
1097        bytes_read = backtrace->Read(reinterpret_cast<uintptr_t>(&g_addr),
1098                                     reinterpret_cast<uint8_t*>(&read_addr),
1099                                     sizeof(uintptr_t));
1100        ASSERT_EQ(sizeof(uintptr_t), bytes_read);
1101
1102        RunReadTest(backtrace.get(), read_addr);
1103
1104        test_executed = true;
1105        break;
1106      }
1107      ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0);
1108    }
1109    if ((NanoTime() - start) > 5 * NS_PER_SEC) {
1110      break;
1111    }
1112    usleep(US_PER_MSEC);
1113  }
1114  kill(pid, SIGKILL);
1115  ASSERT_EQ(waitpid(pid, nullptr, 0), pid);
1116
1117  ASSERT_TRUE(test_executed);
1118}
1119
1120void VerifyFunctionsFound(const std::vector<std::string>& found_functions) {
1121  // We expect to find these functions in libbacktrace_test. If we don't
1122  // find them, that's a bug in the memory read handling code in libunwind.
1123  std::list<std::string> expected_functions;
1124  expected_functions.push_back("test_recursive_call");
1125  expected_functions.push_back("test_level_one");
1126  expected_functions.push_back("test_level_two");
1127  expected_functions.push_back("test_level_three");
1128  expected_functions.push_back("test_level_four");
1129  for (const auto& found_function : found_functions) {
1130    for (const auto& expected_function : expected_functions) {
1131      if (found_function == expected_function) {
1132        expected_functions.remove(found_function);
1133        break;
1134      }
1135    }
1136  }
1137  ASSERT_TRUE(expected_functions.empty()) << "Not all functions found in shared library.";
1138}
1139
1140const char* CopySharedLibrary() {
1141#if defined(__LP64__)
1142  const char* lib_name = "lib64";
1143#else
1144  const char* lib_name = "lib";
1145#endif
1146
1147#if defined(__BIONIC__)
1148  const char* tmp_so_name = "/data/local/tmp/libbacktrace_test.so";
1149  std::string cp_cmd = android::base::StringPrintf("cp /system/%s/libbacktrace_test.so %s",
1150                                                   lib_name, tmp_so_name);
1151#else
1152  const char* tmp_so_name = "/tmp/libbacktrace_test.so";
1153  if (getenv("ANDROID_HOST_OUT") == NULL) {
1154    fprintf(stderr, "ANDROID_HOST_OUT not set, make sure you run lunch.");
1155    return nullptr;
1156  }
1157  std::string cp_cmd = android::base::StringPrintf("cp %s/%s/libbacktrace_test.so %s",
1158                                                   getenv("ANDROID_HOST_OUT"), lib_name,
1159                                                   tmp_so_name);
1160#endif
1161
1162  // Copy the shared so to a tempory directory.
1163  system(cp_cmd.c_str());
1164
1165  return tmp_so_name;
1166}
1167
1168TEST(libbacktrace, check_unreadable_elf_local) {
1169  const char* tmp_so_name = CopySharedLibrary();
1170  ASSERT_TRUE(tmp_so_name != nullptr);
1171
1172  struct stat buf;
1173  ASSERT_TRUE(stat(tmp_so_name, &buf) != -1);
1174  uintptr_t map_size = buf.st_size;
1175
1176  int fd = open(tmp_so_name, O_RDONLY);
1177  ASSERT_TRUE(fd != -1);
1178
1179  void* map = mmap(NULL, map_size, PROT_READ | PROT_EXEC, MAP_PRIVATE, fd, 0);
1180  ASSERT_TRUE(map != MAP_FAILED);
1181  close(fd);
1182  ASSERT_TRUE(unlink(tmp_so_name) != -1);
1183
1184  std::vector<std::string> found_functions;
1185  std::unique_ptr<Backtrace> backtrace(Backtrace::Create(BACKTRACE_CURRENT_PROCESS,
1186                                                         BACKTRACE_CURRENT_THREAD));
1187  ASSERT_TRUE(backtrace.get() != nullptr);
1188
1189  // Needed before GetFunctionName will work.
1190  backtrace->Unwind(0);
1191
1192  // Loop through the entire map, and get every function we can find.
1193  map_size += reinterpret_cast<uintptr_t>(map);
1194  std::string last_func;
1195  for (uintptr_t read_addr = reinterpret_cast<uintptr_t>(map);
1196       read_addr < map_size; read_addr += 4) {
1197    uintptr_t offset;
1198    std::string func_name = backtrace->GetFunctionName(read_addr, &offset);
1199    if (!func_name.empty() && last_func != func_name) {
1200      found_functions.push_back(func_name);
1201    }
1202    last_func = func_name;
1203  }
1204
1205  ASSERT_TRUE(munmap(map, map_size - reinterpret_cast<uintptr_t>(map)) == 0);
1206
1207  VerifyFunctionsFound(found_functions);
1208}
1209
1210TEST(libbacktrace, check_unreadable_elf_remote) {
1211  const char* tmp_so_name = CopySharedLibrary();
1212  ASSERT_TRUE(tmp_so_name != nullptr);
1213
1214  g_ready = 0;
1215
1216  struct stat buf;
1217  ASSERT_TRUE(stat(tmp_so_name, &buf) != -1);
1218  uintptr_t map_size = buf.st_size;
1219
1220  pid_t pid;
1221  if ((pid = fork()) == 0) {
1222    int fd = open(tmp_so_name, O_RDONLY);
1223    if (fd == -1) {
1224      fprintf(stderr, "Failed to open file %s: %s\n", tmp_so_name, strerror(errno));
1225      unlink(tmp_so_name);
1226      exit(0);
1227    }
1228
1229    void* map = mmap(NULL, map_size, PROT_READ | PROT_EXEC, MAP_PRIVATE, fd, 0);
1230    if (map == MAP_FAILED) {
1231      fprintf(stderr, "Failed to map in memory: %s\n", strerror(errno));
1232      unlink(tmp_so_name);
1233      exit(0);
1234    }
1235    close(fd);
1236    if (unlink(tmp_so_name) == -1) {
1237      fprintf(stderr, "Failed to unlink: %s\n", strerror(errno));
1238      exit(0);
1239    }
1240
1241    g_addr = reinterpret_cast<uintptr_t>(map);
1242    g_ready = 1;
1243    while (true) {
1244      usleep(US_PER_MSEC);
1245    }
1246    exit(0);
1247  }
1248  ASSERT_TRUE(pid > 0);
1249
1250  std::vector<std::string> found_functions;
1251  uint64_t start = NanoTime();
1252  while (true) {
1253    ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0);
1254
1255    // Wait for the process to get to a stopping point.
1256    WaitForStop(pid);
1257
1258    std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, BACKTRACE_CURRENT_THREAD));
1259    ASSERT_TRUE(backtrace.get() != nullptr);
1260
1261    uintptr_t read_addr;
1262    ASSERT_EQ(sizeof(uintptr_t), backtrace->Read(reinterpret_cast<uintptr_t>(&g_ready), reinterpret_cast<uint8_t*>(&read_addr), sizeof(uintptr_t)));
1263    if (read_addr) {
1264      ASSERT_EQ(sizeof(uintptr_t), backtrace->Read(reinterpret_cast<uintptr_t>(&g_addr), reinterpret_cast<uint8_t*>(&read_addr), sizeof(uintptr_t)));
1265
1266      // Needed before GetFunctionName will work.
1267      backtrace->Unwind(0);
1268
1269      // Loop through the entire map, and get every function we can find.
1270      map_size += read_addr;
1271      std::string last_func;
1272      for (; read_addr < map_size; read_addr += 4) {
1273        uintptr_t offset;
1274        std::string func_name = backtrace->GetFunctionName(read_addr, &offset);
1275        if (!func_name.empty() && last_func != func_name) {
1276          found_functions.push_back(func_name);
1277        }
1278        last_func = func_name;
1279      }
1280      break;
1281    }
1282    ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0);
1283
1284    if ((NanoTime() - start) > 5 * NS_PER_SEC) {
1285      break;
1286    }
1287    usleep(US_PER_MSEC);
1288  }
1289
1290  kill(pid, SIGKILL);
1291  ASSERT_EQ(waitpid(pid, nullptr, 0), pid);
1292
1293  VerifyFunctionsFound(found_functions);
1294}
1295
1296bool FindFuncFrameInBacktrace(Backtrace* backtrace, uintptr_t test_func, size_t* frame_num) {
1297  backtrace_map_t map;
1298  backtrace->FillInMap(test_func, &map);
1299  if (!BacktraceMap::IsValid(map)) {
1300    return false;
1301  }
1302
1303  // Loop through the frames, and find the one that is in the map.
1304  *frame_num = 0;
1305  for (Backtrace::const_iterator it = backtrace->begin(); it != backtrace->end(); ++it) {
1306    if (BacktraceMap::IsValid(it->map) && map.start == it->map.start &&
1307        it->pc >= test_func) {
1308      *frame_num = it->num;
1309      return true;
1310    }
1311  }
1312  return false;
1313}
1314
1315void VerifyUnreadableElfFrame(Backtrace* backtrace, uintptr_t test_func, size_t frame_num) {
1316  ASSERT_LT(backtrace->NumFrames(), static_cast<size_t>(MAX_BACKTRACE_FRAMES))
1317    << DumpFrames(backtrace);
1318
1319  ASSERT_TRUE(frame_num != 0) << DumpFrames(backtrace);
1320  // Make sure that there is at least one more frame above the test func call.
1321  ASSERT_LT(frame_num, backtrace->NumFrames()) << DumpFrames(backtrace);
1322
1323  uintptr_t diff = backtrace->GetFrame(frame_num)->pc - test_func;
1324  ASSERT_LT(diff, 200U) << DumpFrames(backtrace);
1325}
1326
1327void VerifyUnreadableElfBacktrace(uintptr_t test_func) {
1328  std::unique_ptr<Backtrace> backtrace(Backtrace::Create(BACKTRACE_CURRENT_PROCESS,
1329                                                         BACKTRACE_CURRENT_THREAD));
1330  ASSERT_TRUE(backtrace.get() != nullptr);
1331  ASSERT_TRUE(backtrace->Unwind(0));
1332  ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
1333
1334  size_t frame_num;
1335  ASSERT_TRUE(FindFuncFrameInBacktrace(backtrace.get(), test_func, &frame_num));
1336
1337  VerifyUnreadableElfFrame(backtrace.get(), test_func, frame_num);
1338}
1339
1340typedef int (*test_func_t)(int, int, int, int, void (*)(uintptr_t), uintptr_t);
1341
1342TEST(libbacktrace, unwind_through_unreadable_elf_local) {
1343  const char* tmp_so_name = CopySharedLibrary();
1344  ASSERT_TRUE(tmp_so_name != nullptr);
1345  void* lib_handle = dlopen(tmp_so_name, RTLD_NOW);
1346  ASSERT_TRUE(lib_handle != nullptr);
1347  ASSERT_TRUE(unlink(tmp_so_name) != -1);
1348
1349  test_func_t test_func;
1350  test_func = reinterpret_cast<test_func_t>(dlsym(lib_handle, "test_level_one"));
1351  ASSERT_TRUE(test_func != nullptr);
1352
1353  ASSERT_NE(test_func(1, 2, 3, 4, VerifyUnreadableElfBacktrace,
1354                      reinterpret_cast<uintptr_t>(test_func)), 0);
1355
1356  ASSERT_TRUE(dlclose(lib_handle) == 0);
1357}
1358
1359TEST(libbacktrace, unwind_through_unreadable_elf_remote) {
1360  const char* tmp_so_name = CopySharedLibrary();
1361  ASSERT_TRUE(tmp_so_name != nullptr);
1362  void* lib_handle = dlopen(tmp_so_name, RTLD_NOW);
1363  ASSERT_TRUE(lib_handle != nullptr);
1364  ASSERT_TRUE(unlink(tmp_so_name) != -1);
1365
1366  test_func_t test_func;
1367  test_func = reinterpret_cast<test_func_t>(dlsym(lib_handle, "test_level_one"));
1368  ASSERT_TRUE(test_func != nullptr);
1369
1370  pid_t pid;
1371  if ((pid = fork()) == 0) {
1372    test_func(1, 2, 3, 4, 0, 0);
1373    exit(0);
1374  }
1375  ASSERT_TRUE(pid > 0);
1376  ASSERT_TRUE(dlclose(lib_handle) == 0);
1377
1378  uint64_t start = NanoTime();
1379  bool done = false;
1380  while (!done) {
1381    ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0);
1382
1383    // Wait for the process to get to a stopping point.
1384    WaitForStop(pid);
1385
1386    std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, BACKTRACE_CURRENT_THREAD));
1387    ASSERT_TRUE(backtrace.get() != nullptr);
1388    ASSERT_TRUE(backtrace->Unwind(0));
1389    ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
1390
1391    size_t frame_num;
1392    if (FindFuncFrameInBacktrace(backtrace.get(),
1393                                 reinterpret_cast<uintptr_t>(test_func), &frame_num)) {
1394
1395      VerifyUnreadableElfFrame(backtrace.get(), reinterpret_cast<uintptr_t>(test_func), frame_num);
1396      done = true;
1397    }
1398
1399    ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0);
1400
1401    if ((NanoTime() - start) > 5 * NS_PER_SEC) {
1402      break;
1403    }
1404    usleep(US_PER_MSEC);
1405  }
1406
1407  kill(pid, SIGKILL);
1408  ASSERT_EQ(waitpid(pid, nullptr, 0), pid);
1409
1410  ASSERT_TRUE(done) << "Test function never found in unwind.";
1411}
1412
1413TEST(libbacktrace, unwind_thread_doesnt_exist) {
1414  std::unique_ptr<Backtrace> backtrace(
1415      Backtrace::Create(BACKTRACE_CURRENT_PROCESS, 99999999));
1416  ASSERT_TRUE(backtrace.get() != nullptr);
1417  ASSERT_FALSE(backtrace->Unwind(0));
1418  ASSERT_EQ(BACKTRACE_UNWIND_ERROR_THREAD_DOESNT_EXIST, backtrace->GetError());
1419}
1420
1421#if defined(ENABLE_PSS_TESTS)
1422#include "GetPss.h"
1423
1424#define MAX_LEAK_BYTES 32*1024UL
1425
1426void CheckForLeak(pid_t pid, pid_t tid) {
1427  // Do a few runs to get the PSS stable.
1428  for (size_t i = 0; i < 100; i++) {
1429    Backtrace* backtrace = Backtrace::Create(pid, tid);
1430    ASSERT_TRUE(backtrace != nullptr);
1431    ASSERT_TRUE(backtrace->Unwind(0));
1432    ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
1433    delete backtrace;
1434  }
1435  size_t stable_pss = GetPssBytes();
1436  ASSERT_TRUE(stable_pss != 0);
1437
1438  // Loop enough that even a small leak should be detectable.
1439  for (size_t i = 0; i < 4096; i++) {
1440    Backtrace* backtrace = Backtrace::Create(pid, tid);
1441    ASSERT_TRUE(backtrace != nullptr);
1442    ASSERT_TRUE(backtrace->Unwind(0));
1443    ASSERT_EQ(BACKTRACE_UNWIND_NO_ERROR, backtrace->GetError());
1444    delete backtrace;
1445  }
1446  size_t new_pss = GetPssBytes();
1447  ASSERT_TRUE(new_pss != 0);
1448  size_t abs_diff = (new_pss > stable_pss) ? new_pss - stable_pss : stable_pss - new_pss;
1449  // As long as the new pss is within a certain amount, consider everything okay.
1450  ASSERT_LE(abs_diff, MAX_LEAK_BYTES);
1451}
1452
1453TEST(libbacktrace, check_for_leak_local) {
1454  CheckForLeak(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD);
1455}
1456
1457TEST(libbacktrace, check_for_leak_local_thread) {
1458  thread_t thread_data = { 0, 0, 0, nullptr };
1459  pthread_t thread;
1460  ASSERT_TRUE(pthread_create(&thread, nullptr, ThreadLevelRun, &thread_data) == 0);
1461
1462  // Wait up to 2 seconds for the tid to be set.
1463  ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2));
1464
1465  CheckForLeak(BACKTRACE_CURRENT_PROCESS, thread_data.tid);
1466
1467  // Tell the thread to exit its infinite loop.
1468  android_atomic_acquire_store(0, &thread_data.state);
1469
1470  ASSERT_TRUE(pthread_join(thread, nullptr) == 0);
1471}
1472
1473TEST(libbacktrace, check_for_leak_remote) {
1474  pid_t pid;
1475
1476  if ((pid = fork()) == 0) {
1477    while (true) {
1478    }
1479    _exit(0);
1480  }
1481  ASSERT_LT(0, pid);
1482
1483  ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0);
1484
1485  // Wait for the process to get to a stopping point.
1486  WaitForStop(pid);
1487
1488  CheckForLeak(pid, BACKTRACE_CURRENT_THREAD);
1489
1490  ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0);
1491
1492  kill(pid, SIGKILL);
1493  ASSERT_EQ(waitpid(pid, nullptr, 0), pid);
1494}
1495#endif
1496