xref: /external/chromium_org/third_party/tcmalloc/vendor/src/tests/heap-checker_unittest.cc

// Copyright (c) 2005, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// ---
// Author: Maxim Lifantsev
//
// Running:
// ./heap-checker_unittest
//
// If the unittest crashes because it can't find pprof, try:
// PPROF_PATH=/usr/local/someplace/bin/pprof ./heap-checker_unittest
//
// To test that the whole-program heap checker will actually cause a leak, try:
// HEAPCHECK_TEST_LEAK= ./heap-checker_unittest
// HEAPCHECK_TEST_LOOP_LEAK= ./heap-checker_unittest
//
// Note: Both of the above commands *should* abort with an error message.

// CAVEAT: Do not use vector<> and string on-heap objects in this test,
// otherwise the test can sometimes fail for tricky leak checks
// when we want some allocated object not to be found live by the heap checker.
// This can happen with memory allocators like tcmalloc that can allocate
// heap objects back to back without any book-keeping data in between.
// What happens is that end-of-storage pointers of a live vector
// (or a string depending on the STL implementation used)
// can happen to point to that other heap-allocated
// object that is not reachable otherwise and that
// we don't want to be reachable.
//
// The implication of this for real leak checking
// is just one more chance for the liveness flood to be inexact
// (see the comment in our .h file).

#include "config_for_unittests.h"
#ifdef HAVE_POLL_H
#include <poll.h>
#endif
#if defined HAVE_STDINT_H
#include <stdint.h>             // to get uint16_t (ISO naming madness)
#elif defined HAVE_INTTYPES_H
#include <inttypes.h>           // another place uint16_t might be defined
#endif
#include <sys/types.h>
#include <stdlib.h>
#include <errno.h>              // errno
#ifdef HAVE_UNISTD_H
#include <unistd.h>             // for sleep(), geteuid()
#endif
#ifdef HAVE_MMAP
#include <sys/mman.h>
#endif
#include <fcntl.h>              // for open(), close()
#ifdef HAVE_EXECINFO_H
#include <execinfo.h>           // backtrace
#endif
#ifdef HAVE_GRP_H
#include <grp.h>                // getgrent, getgrnam
#endif
#ifdef HAVE_PWD_H
#include <pwd.h>
#endif

#include <algorithm>
#include <iostream>             // for cout
#include <iomanip>              // for hex
#include <list>
#include <map>
#include <memory>
#include <set>
#include <string>
#include <vector>

#include "base/commandlineflags.h"
#include "base/googleinit.h"
#include "base/logging.h"
#include "base/commandlineflags.h"
#include "base/thread_lister.h"
#include <gperftools/heap-checker.h>
#include "memory_region_map.h"
#include <gperftools/malloc_extension.h>
#include <gperftools/stacktrace.h>

// On systems (like freebsd) that don't define MAP_ANONYMOUS, use the old
// form of the name instead.
#ifndef MAP_ANONYMOUS
# define MAP_ANONYMOUS MAP_ANON
#endif

using namespace std;

// ========================================================================= //

// TODO(maxim): write a shell script to test that these indeed crash us
//              (i.e. we do detect leaks)
//              Maybe add more such crash tests.

DEFINE_bool(test_leak,
            EnvToBool("HEAP_CHECKER_TEST_TEST_LEAK", false),
            "If should cause a leak crash");
DEFINE_bool(test_loop_leak,
            EnvToBool("HEAP_CHECKER_TEST_TEST_LOOP_LEAK", false),
            "If should cause a looped leak crash");
DEFINE_bool(test_register_leak,
            EnvToBool("HEAP_CHECKER_TEST_TEST_REGISTER_LEAK", false),
            "If should cause a leak crash by hiding a pointer "
            "that is only in a register");
DEFINE_bool(test_cancel_global_check,
            EnvToBool("HEAP_CHECKER_TEST_TEST_CANCEL_GLOBAL_CHECK", false),
            "If should test HeapLeakChecker::CancelGlobalCheck "
            "when --test_leak or --test_loop_leak are given; "
            "the test should not fail then");
DEFINE_bool(maybe_stripped,
            EnvToBool("HEAP_CHECKER_TEST_MAYBE_STRIPPED", true),
            "If we think we can be a stripped binary");
DEFINE_bool(interfering_threads,
            EnvToBool("HEAP_CHECKER_TEST_INTERFERING_THREADS", true),
            "If we should use threads trying "
            "to interfere with leak checking");
DEFINE_bool(hoarding_threads,
            EnvToBool("HEAP_CHECKER_TEST_HOARDING_THREADS", true),
            "If threads (usually the manager thread) are known "
            "to retain some old state in their global buffers, "
            "so that it's hard to force leaks when threads are around");
            // TODO(maxim): Chage the default to false
            // when the standard environment used NTPL threads:
            // they do not seem to have this problem.
DEFINE_bool(no_threads,
            EnvToBool("HEAP_CHECKER_TEST_NO_THREADS", false),
            "If we should not use any threads");
            // This is used so we can make can_create_leaks_reliably true
            // for any pthread implementation and test with that.

DECLARE_int64(heap_check_max_pointer_offset);   // heap-checker.cc
DECLARE_string(heap_check);  // in heap-checker.cc

#define WARN_IF(cond, msg)   LOG_IF(WARNING, cond, msg)

// This is an evil macro!  Be very careful using it...
#undef VLOG          // and we start by evilling overriding logging.h VLOG
#define VLOG(lvl)    if (FLAGS_verbose >= (lvl))  cout << "\n"
// This is, likewise, evil
#define LOGF         VLOG(INFO)

static void RunHeapBusyThreads();  // below


class Closure {
 public:
  virtual ~Closure() { }
  virtual void Run() = 0;
};

class Callback0 : public Closure {
 public:
  typedef void (*FunctionSignature)();

  inline Callback0(FunctionSignature f) : f_(f) {}
  virtual void Run() { (*f_)(); delete this; }

 private:
  FunctionSignature f_;
};

template <class P1> class Callback1 : public Closure {
 public:
  typedef void (*FunctionSignature)(P1);

  inline Callback1<P1>(FunctionSignature f, P1 p1) : f_(f), p1_(p1) {}
  virtual void Run() { (*f_)(p1_); delete this; }

 private:
  FunctionSignature f_;
  P1 p1_;
};

template <class P1, class P2> class Callback2 : public Closure {
 public:
  typedef void (*FunctionSignature)(P1,P2);

  inline Callback2<P1,P2>(FunctionSignature f, P1 p1, P2 p2) : f_(f), p1_(p1), p2_(p2) {}
  virtual void Run() { (*f_)(p1_, p2_); delete this; }

 private:
  FunctionSignature f_;
  P1 p1_;
  P2 p2_;
};

inline Callback0* NewCallback(void (*function)()) {
  return new Callback0(function);
}

template <class P1>
inline Callback1<P1>* NewCallback(void (*function)(P1), P1 p1) {
  return new Callback1<P1>(function, p1);
}

template <class P1, class P2>
inline Callback2<P1,P2>* NewCallback(void (*function)(P1,P2), P1 p1, P2 p2) {
  return new Callback2<P1,P2>(function, p1, p2);
}


// Set to true at end of main, so threads know.  Not entirely thread-safe!,
// but probably good enough.
static bool g_have_exited_main = false;

// If we can reliably create leaks (i.e. make leaked object
// really unreachable from any global data).
static bool can_create_leaks_reliably = false;

// We use a simple allocation wrapper
// to make sure we wipe out the newly allocated objects
// in case they still happened to contain some pointer data
// accidentally left by the memory allocator.
struct Initialized { };
static Initialized initialized;
void* operator new(size_t size, const Initialized&) {
  // Below we use "p = new(initialized) Foo[1];" and  "delete[] p;"
  // instead of "p = new(initialized) Foo;"
  // when we need to delete an allocated object.
  void* p = malloc(size);
  memset(p, 0, size);
  return p;
}
void* operator new[](size_t size, const Initialized&) {
  char* p = new char[size];
  memset(p, 0, size);
  return p;
}

static void DoWipeStack(int n);  // defined below
static void WipeStack() { DoWipeStack(20); }

static void Pause() {
  poll(NULL, 0, 77);  // time for thread activity in HeapBusyThreadBody

  // Indirectly test malloc_extension.*:
  CHECK(MallocExtension::instance()->VerifyAllMemory());
  int blocks;
  size_t total;
  int histogram[kMallocHistogramSize];
  if (MallocExtension::instance()
       ->MallocMemoryStats(&blocks, &total, histogram)  &&  total != 0) {
    VLOG(3) << "Malloc stats: " << blocks << " blocks of "
            << total << " bytes";
    for (int i = 0; i < kMallocHistogramSize; ++i) {
      if (histogram[i]) {
        VLOG(3) << "  Malloc histogram at " << i << " : " << histogram[i];
      }
    }
  }
  WipeStack();  // e.g. MallocExtension::VerifyAllMemory
                // can leave pointers to heap objects on stack
}

// Make gcc think a pointer is "used"
template <class T>
static void Use(T** foo) {
  VLOG(2) << "Dummy-using " << static_cast<void*>(*foo) << " at " << foo;
}

// Arbitrary value, but not such that xor'ing with it is likely
// to map one valid pointer to another valid pointer:
static const uintptr_t kHideMask =
  static_cast<uintptr_t>(0xF03A5F7BF03A5F7BLL);

// Helpers to hide a pointer from live data traversal.
// We just xor the pointer so that (with high probability)
// it's not a valid address of a heap object anymore.
// Both Hide and UnHide must be executed within RunHidden() below
// to prevent leaving stale data on active stack that can be a pointer
// to a heap object that is not actually reachable via live variables.
// (UnHide might leave heap pointer value for an object
//  that will be deallocated but later another object
//  can be allocated at the same heap address.)
template <class T>
static void Hide(T** ptr) {
  // we cast values, not dereferenced pointers, so no aliasing issues:
  *ptr = reinterpret_cast<T*>(reinterpret_cast<uintptr_t>(*ptr) ^ kHideMask);
  VLOG(2) << "hid: " << static_cast<void*>(*ptr);
}

template <class T>
static void UnHide(T** ptr) {
  VLOG(2) << "unhiding: " << static_cast<void*>(*ptr);
  // we cast values, not dereferenced pointers, so no aliasing issues:
  *ptr = reinterpret_cast<T*>(reinterpret_cast<uintptr_t>(*ptr) ^ kHideMask);
}

static void LogHidden(const char* message, const void* ptr) {
  LOGF << message << " : "
       << ptr << " ^ " << reinterpret_cast<void*>(kHideMask) << endl;
}

// volatile to fool the compiler against inlining the calls to these
void (*volatile run_hidden_ptr)(Closure* c, int n);
void (*volatile wipe_stack_ptr)(int n);

static void DoRunHidden(Closure* c, int n) {
  if (n) {
    VLOG(10) << "Level " << n << " at " << &n;
    (*run_hidden_ptr)(c, n-1);
    (*wipe_stack_ptr)(n);
    sleep(0);  // undo -foptimize-sibling-calls
  } else {
    c->Run();
  }
}

/*static*/ void DoWipeStack(int n) {
  VLOG(10) << "Wipe level " << n << " at " << &n;
  if (n) {
    const int sz = 30;
    volatile int arr[sz];
    for (int i = 0; i < sz; ++i) arr[i] = 0;
    (*wipe_stack_ptr)(n-1);
    sleep(0);  // undo -foptimize-sibling-calls
  }
}

// This executes closure c several stack frames down from the current one
// and then makes an effort to also wipe out the stack data that was used by
// the closure.
// This way we prevent leak checker from finding any temporary pointers
// of the closure execution on the stack and deciding that
// these pointers (and the pointed objects) are still live.
static void RunHidden(Closure* c) {
  DoRunHidden(c, 15);
  DoWipeStack(20);
}

static void DoAllocHidden(size_t size, void** ptr) {
  void* p = new(initialized) char[size];
  Hide(&p);
  Use(&p);  // use only hidden versions
  VLOG(2) << "Allocated hidden " << p << " at " << &p;
  *ptr = p;  // assign the hidden versions
}

static void* AllocHidden(size_t size) {
  void* r;
  RunHidden(NewCallback(DoAllocHidden, size, &r));
  return r;
}

static void DoDeAllocHidden(void** ptr) {
  Use(ptr);  // use only hidden versions
  void* p = *ptr;
  VLOG(2) << "Deallocating hidden " << p;
  UnHide(&p);
  delete [] reinterpret_cast<char*>(p);
}

static void DeAllocHidden(void** ptr) {
  RunHidden(NewCallback(DoDeAllocHidden, ptr));
  *ptr = NULL;
  Use(ptr);
}

void PreventHeapReclaiming(size_t size) {
#ifdef NDEBUG
  if (true) {
    static void** no_reclaim_list = NULL;
    CHECK(size >= sizeof(void*));
    // We can't use malloc_reclaim_memory flag in opt mode as debugallocation.cc
    // is not used. Instead we allocate a bunch of heap objects that are
    // of the same size as what we are going to leak to ensure that the object
    // we are about to leak is not at the same address as some old allocated
    // and freed object that might still have pointers leading to it.
    for (int i = 0; i < 100; ++i) {
      void** p = reinterpret_cast<void**>(new(initialized) char[size]);
      p[0] = no_reclaim_list;
      no_reclaim_list = p;
    }
  }
#endif
}

static bool RunSilent(HeapLeakChecker* check,
                      bool (HeapLeakChecker::* func)()) {
  // By default, don't print the 'we detected a leak' message in the
  // cases we're expecting a leak (we still print when --v is >= 1).
  // This way, the logging output is less confusing: we only print
  // "we detected a leak", and how to diagnose it, for *unexpected* leaks.
  int32 old_FLAGS_verbose = FLAGS_verbose;
  if (!VLOG_IS_ON(1))             // not on a verbose setting
    FLAGS_verbose = FATAL;        // only log fatal errors
  const bool retval = (check->*func)();
  FLAGS_verbose = old_FLAGS_verbose;
  return retval;
}

#define RUN_SILENT(check, func)  RunSilent(&(check), &HeapLeakChecker::func)

enum CheckType { SAME_HEAP, NO_LEAKS };

static void VerifyLeaks(HeapLeakChecker* check, CheckType type,
                        int leaked_bytes, int leaked_objects) {
  WipeStack();  // to help with can_create_leaks_reliably
  const bool no_leaks =
    type == NO_LEAKS ? RUN_SILENT(*check, BriefNoLeaks)
                     : RUN_SILENT(*check, BriefSameHeap);
  if (can_create_leaks_reliably) {
    // these might still fail occasionally, but it should be very rare
    CHECK_EQ(no_leaks, false);
    CHECK_EQ(check->BytesLeaked(), leaked_bytes);
    CHECK_EQ(check->ObjectsLeaked(), leaked_objects);
  } else {
    WARN_IF(no_leaks != false,
            "Expected leaks not found: "
            "Some liveness flood must be too optimistic");
  }
}

// not deallocates
static void TestHeapLeakCheckerDeathSimple() {
  HeapLeakChecker check("death_simple");
  void* foo = AllocHidden(100 * sizeof(int));
  Use(&foo);
  void* bar = AllocHidden(300);
  Use(&bar);
  LogHidden("Leaking", foo);
  LogHidden("Leaking", bar);
  Pause();
  VerifyLeaks(&check, NO_LEAKS, 300 + 100 * sizeof(int), 2);
  DeAllocHidden(&foo);
  DeAllocHidden(&bar);
}

static void MakeDeathLoop(void** arr1, void** arr2) {
  PreventHeapReclaiming(2 * sizeof(void*));
  void** a1 = new(initialized) void*[2];
  void** a2 = new(initialized) void*[2];
  a1[1] = reinterpret_cast<void*>(a2);
  a2[1] = reinterpret_cast<void*>(a1);
  Hide(&a1);
  Hide(&a2);
  Use(&a1);
  Use(&a2);
  VLOG(2) << "Made hidden loop at " << &a1 << " to " << arr1;
  *arr1 = a1;
  *arr2 = a2;
}

// not deallocates two objects linked together
static void TestHeapLeakCheckerDeathLoop() {
  HeapLeakChecker check("death_loop");
  void* arr1;
  void* arr2;
  RunHidden(NewCallback(MakeDeathLoop, &arr1, &arr2));
  Use(&arr1);
  Use(&arr2);
  LogHidden("Leaking", arr1);
  LogHidden("Leaking", arr2);
  Pause();
  VerifyLeaks(&check, NO_LEAKS, 4 * sizeof(void*), 2);
  DeAllocHidden(&arr1);
  DeAllocHidden(&arr2);
}

// deallocates more than allocates
static void TestHeapLeakCheckerDeathInverse() {
  void* bar = AllocHidden(250 * sizeof(int));
  Use(&bar);
  LogHidden("Pre leaking", bar);
  Pause();
  HeapLeakChecker check("death_inverse");
  void* foo = AllocHidden(100 * sizeof(int));
  Use(&foo);
  LogHidden("Leaking", foo);
  DeAllocHidden(&bar);
  Pause();
  VerifyLeaks(&check, SAME_HEAP,
              100 * static_cast<int64>(sizeof(int)),
              1);
  DeAllocHidden(&foo);
}

// deallocates more than allocates
static void TestHeapLeakCheckerDeathNoLeaks() {
  void* foo = AllocHidden(100 * sizeof(int));
  Use(&foo);
  void* bar = AllocHidden(250 * sizeof(int));
  Use(&bar);
  HeapLeakChecker check("death_noleaks");
  DeAllocHidden(&bar);
  CHECK_EQ(check.BriefNoLeaks(), true);
  DeAllocHidden(&foo);
}

// have less objecs
static void TestHeapLeakCheckerDeathCountLess() {
  void* bar1 = AllocHidden(50 * sizeof(int));
  Use(&bar1);
  void* bar2 = AllocHidden(50 * sizeof(int));
  Use(&bar2);
  LogHidden("Pre leaking", bar1);
  LogHidden("Pre leaking", bar2);
  Pause();
  HeapLeakChecker check("death_count_less");
  void* foo = AllocHidden(100 * sizeof(int));
  Use(&foo);
  LogHidden("Leaking", foo);
  DeAllocHidden(&bar1);
  DeAllocHidden(&bar2);
  Pause();
  VerifyLeaks(&check, SAME_HEAP,
              100 * sizeof(int),
              1);
  DeAllocHidden(&foo);
}

// have more objecs
static void TestHeapLeakCheckerDeathCountMore() {
  void* foo = AllocHidden(100 * sizeof(int));
  Use(&foo);
  LogHidden("Pre leaking", foo);
  Pause();
  HeapLeakChecker check("death_count_more");
  void* bar1 = AllocHidden(50 * sizeof(int));
  Use(&bar1);
  void* bar2 = AllocHidden(50 * sizeof(int));
  Use(&bar2);
  LogHidden("Leaking", bar1);
  LogHidden("Leaking", bar2);
  DeAllocHidden(&foo);
  Pause();
  VerifyLeaks(&check, SAME_HEAP,
              100 * sizeof(int),
              2);
  DeAllocHidden(&bar1);
  DeAllocHidden(&bar2);
}

static void TestHiddenPointer() {
  int i;
  void* foo = &i;
  HiddenPointer<void> p(foo);
  CHECK_EQ(foo, p.get());

  // Confirm pointer doesn't appear to contain a byte sequence
  // that == the pointer.  We don't really need to test that
  // the xor trick itself works, as without it nothing in this
  // test suite would work.  See the Hide/Unhide/*Hidden* set
  // of helper methods.
  CHECK_NE(foo, *reinterpret_cast<void**>(&p));
}

// simple tests that deallocate what they allocated
static void TestHeapLeakChecker() {
  { HeapLeakChecker check("trivial");
    int foo = 5;
    int* p = &foo;
    Use(&p);
    Pause();
    CHECK(check.BriefSameHeap());
  }
  Pause();
  { HeapLeakChecker check("simple");
    void* foo = AllocHidden(100 * sizeof(int));
    Use(&foo);
    void* bar = AllocHidden(200 * sizeof(int));
    Use(&bar);
    DeAllocHidden(&foo);
    DeAllocHidden(&bar);
    Pause();
    CHECK(check.BriefSameHeap());
  }
}

// no false positives
static void TestHeapLeakCheckerNoFalsePositives() {
  { HeapLeakChecker check("trivial_p");
    int foo = 5;
    int* p = &foo;
    Use(&p);
    Pause();
    CHECK(check.BriefSameHeap());
  }
  Pause();
  { HeapLeakChecker check("simple_p");
    void* foo = AllocHidden(100 * sizeof(int));
    Use(&foo);
    void* bar = AllocHidden(200 * sizeof(int));
    Use(&bar);
    DeAllocHidden(&foo);
    DeAllocHidden(&bar);
    Pause();
    CHECK(check.SameHeap());
  }
}

// test that we detect leaks when we have same total # of bytes and
// objects, but different individual object sizes
static void TestLeakButTotalsMatch() {
  void* bar1 = AllocHidden(240 * sizeof(int));
  Use(&bar1);
  void* bar2 = AllocHidden(160 * sizeof(int));
  Use(&bar2);
  LogHidden("Pre leaking", bar1);
  LogHidden("Pre leaking", bar2);
  Pause();
  HeapLeakChecker check("trick");
  void* foo1 = AllocHidden(280 * sizeof(int));
  Use(&foo1);
  void* foo2 = AllocHidden(120 * sizeof(int));
  Use(&foo2);
  LogHidden("Leaking", foo1);
  LogHidden("Leaking", foo2);
  DeAllocHidden(&bar1);
  DeAllocHidden(&bar2);
  Pause();

  // foo1 and foo2 leaked
  VerifyLeaks(&check, NO_LEAKS, (280+120)*sizeof(int), 2);

  DeAllocHidden(&foo1);
  DeAllocHidden(&foo2);
}

// no false negatives from pprof
static void TestHeapLeakCheckerDeathTrick() {
  void* bar1 = AllocHidden(240 * sizeof(int));
  Use(&bar1);
  void* bar2 = AllocHidden(160 * sizeof(int));
  Use(&bar2);
  HeapLeakChecker check("death_trick");
  DeAllocHidden(&bar1);
  DeAllocHidden(&bar2);
  void* foo1 = AllocHidden(280 * sizeof(int));
  Use(&foo1);
  void* foo2 = AllocHidden(120 * sizeof(int));
  Use(&foo2);
  // TODO(maxim): use the above if we make pprof work in automated test runs
  if (!FLAGS_maybe_stripped) {
    CHECK_EQ(RUN_SILENT(check, SameHeap), false);
      // pprof checking should catch the leak
  } else {
    WARN_IF(RUN_SILENT(check, SameHeap) != false,
            "death_trick leak is not caught; "
            "we must be using a stripped binary");
  }
  DeAllocHidden(&foo1);
  DeAllocHidden(&foo2);
}

// simple leak
static void TransLeaks() {
  AllocHidden(1 * sizeof(char));
}

// range-based disabling using Disabler
static void ScopedDisabledLeaks() {
  HeapLeakChecker::Disabler disabler;
  AllocHidden(3 * sizeof(int));
  TransLeaks();
  (void)malloc(10);  // Direct leak
}

// have different disabled leaks
static void* RunDisabledLeaks(void* a) {
  ScopedDisabledLeaks();
  return a;
}

// have different disabled leaks inside of a thread
static void ThreadDisabledLeaks() {
  if (FLAGS_no_threads)  return;
  pthread_t tid;
  pthread_attr_t attr;
  CHECK_EQ(pthread_attr_init(&attr), 0);
  CHECK_EQ(pthread_create(&tid, &attr, RunDisabledLeaks, NULL), 0);
  void* res;
  CHECK_EQ(pthread_join(tid, &res), 0);
}

// different disabled leaks (some in threads)
static void TestHeapLeakCheckerDisabling() {
  HeapLeakChecker check("disabling");

  RunDisabledLeaks(NULL);
  RunDisabledLeaks(NULL);
  ThreadDisabledLeaks();
  RunDisabledLeaks(NULL);
  ThreadDisabledLeaks();
  ThreadDisabledLeaks();

  Pause();

  CHECK(check.SameHeap());
}

typedef set<int> IntSet;

static int some_ints[] = { 1, 2, 3, 21, 22, 23, 24, 25 };

static void DoTestSTLAlloc() {
  IntSet* x = new(initialized) IntSet[1];
  *x = IntSet(some_ints, some_ints + 6);
  for (int i = 0; i < 1000; i++) {
    x->insert(i*3);
  }
  delete [] x;
}

// Check that normal STL usage does not result in a leak report.
// (In particular we test that there's no complex STL's own allocator
// running on top of our allocator with hooks to heap profiler
// that can result in false leak report in this case.)
static void TestSTLAlloc() {
  HeapLeakChecker check("stl");
  RunHidden(NewCallback(DoTestSTLAlloc));
  CHECK_EQ(check.BriefSameHeap(), true);
}

static void DoTestSTLAllocInverse(IntSet** setx) {
  IntSet* x = new(initialized) IntSet[1];
  *x = IntSet(some_ints, some_ints + 3);
  for (int i = 0; i < 100; i++) {
    x->insert(i*2);
  }
  Hide(&x);
  *setx = x;
}

static void FreeTestSTLAllocInverse(IntSet** setx) {
  IntSet* x = *setx;
  UnHide(&x);
  delete [] x;
}

// Check that normal leaked STL usage *does* result in a leak report.
// (In particular we test that there's no complex STL's own allocator
// running on top of our allocator with hooks to heap profiler
// that can result in false absence of leak report in this case.)
static void TestSTLAllocInverse() {
  HeapLeakChecker check("death_inverse_stl");
  IntSet* x;
  RunHidden(NewCallback(DoTestSTLAllocInverse, &x));
  LogHidden("Leaking", x);
  if (can_create_leaks_reliably) {
    WipeStack();  // to help with can_create_leaks_reliably
    // these might still fail occasionally, but it should be very rare
    CHECK_EQ(RUN_SILENT(check, BriefNoLeaks), false);
    CHECK_GE(check.BytesLeaked(), 100 * sizeof(int));
    CHECK_GE(check.ObjectsLeaked(), 100);
      // assumes set<>s are represented by some kind of binary tree
      // or something else allocating >=1 heap object per set object
  } else {
    WARN_IF(RUN_SILENT(check, BriefNoLeaks) != false,
            "Expected leaks not found: "
            "Some liveness flood must be too optimistic");
  }
  RunHidden(NewCallback(FreeTestSTLAllocInverse, &x));
}

template<class Alloc>
static void DirectTestSTLAlloc(Alloc allocator, const char* name) {
  HeapLeakChecker check((string("direct_stl-") + name).c_str());
  static const int kSize = 1000;
  typename Alloc::pointer ptrs[kSize];
  for (int i = 0; i < kSize; ++i) {
    typename Alloc::pointer p = allocator.allocate(i*3+1);
    HeapLeakChecker::IgnoreObject(p);
    // This will crash if p is not known to heap profiler:
    // (i.e. STL's "allocator" does not have a direct hook to heap profiler)
    HeapLeakChecker::UnIgnoreObject(p);
    ptrs[i] = p;
  }
  for (int i = 0; i < kSize; ++i) {
    allocator.deallocate(ptrs[i], i*3+1);
    ptrs[i] = NULL;
  }
  CHECK(check.BriefSameHeap());  // just in case
}

static struct group* grp = NULL;
static const int kKeys = 50;
static pthread_key_t key[kKeys];

static void KeyFree(void* ptr) {
  delete [] reinterpret_cast<char*>(ptr);
}

static bool key_init_has_run = false;

static void KeyInit() {
  for (int i = 0; i < kKeys; ++i) {
    CHECK_EQ(pthread_key_create(&key[i], KeyFree), 0);
    VLOG(2) << "pthread key " << i << " : " << key[i];
  }
  key_init_has_run = true;   // needed for a sanity-check
}

// force various C library static and thread-specific allocations
static void TestLibCAllocate() {
  CHECK(key_init_has_run);
  for (int i = 0; i < kKeys; ++i) {
    void* p = pthread_getspecific(key[i]);
    if (NULL == p) {
      if (i == 0) {
        // Test-logging inside threads which (potentially) creates and uses
        // thread-local data inside standard C++ library:
        VLOG(0) << "Adding pthread-specifics for thread " << pthread_self()
                << " pid " << getpid();
      }
      p = new(initialized) char[77 + i];
      VLOG(2) << "pthread specific " << i << " : " << p;
      pthread_setspecific(key[i], p);
    }
  }

  strerror(errno);
  const time_t now = time(NULL);
  ctime(&now);
#ifdef HAVE_EXECINFO_H
  void *stack[1];
  backtrace(stack, 1);
#endif
#ifdef HAVE_GRP_H
  gid_t gid = getgid();
  getgrgid(gid);
  if (grp == NULL)  grp = getgrent();  // a race condition here is okay
  getgrnam(grp->gr_name);
#endif
#ifdef HAVE_PWD_H
  getpwuid(geteuid());
#endif
}

// Continuous random heap memory activity to try to disrupt heap checking.
static void* HeapBusyThreadBody(void* a) {
  const int thread_num = reinterpret_cast<intptr_t>(a);
  VLOG(0) << "A new HeapBusyThread " << thread_num;
  TestLibCAllocate();

  int user = 0;
  // Try to hide ptr from heap checker in a CPU register:
  // Here we are just making a best effort to put the only pointer
  // to a heap object into a thread register to test
  // the thread-register finding machinery in the heap checker.
#if defined(__i386__) && defined(__GNUC__)
  register int** ptr asm("esi");
#elif defined(__x86_64__) && defined(__GNUC__)
  register int** ptr asm("r15");
#else
  register int** ptr;
#endif
  ptr = NULL;
  typedef set<int> Set;
  Set s1;
  while (1) {
    // TestLibCAllocate() calls libc functions that don't work so well
    // after main() has exited.  So we just don't do the test then.
    if (!g_have_exited_main)
      TestLibCAllocate();

    if (ptr == NULL) {
      ptr = new(initialized) int*[1];
      *ptr = new(initialized) int[1];
    }
    set<int>* s2 = new(initialized) set<int>[1];
    s1.insert(random());
    s2->insert(*s1.begin());
    user += *s2->begin();
    **ptr += user;
    if (random() % 51 == 0) {
      s1.clear();
      if (random() % 2 == 0) {
        s1.~Set();
        new(&s1) Set;
      }
    }
    VLOG(3) << pthread_self() << " (" << getpid() << "): in wait: "
            << ptr << ", " << *ptr << "; " << s1.size();
    VLOG(2) << pthread_self() << " (" << getpid() << "): in wait, ptr = "
            << reinterpret_cast<void*>(
                 reinterpret_cast<uintptr_t>(ptr) ^ kHideMask)
            << "^" << reinterpret_cast<void*>(kHideMask);
    if (FLAGS_test_register_leak  &&  thread_num % 5 == 0) {
      // Hide the register "ptr" value with an xor mask.
      // If one provides --test_register_leak flag, the test should
      // (with very high probability) crash on some leak check
      // with a leak report (of some x * sizeof(int) + y * sizeof(int*) bytes)
      // pointing at the two lines above in this function
      // with "new(initialized) int" in them as the allocators
      // of the leaked objects.
      // CAVEAT: We can't really prevent a compiler to save some
      // temporary values of "ptr" on the stack and thus let us find
      // the heap objects not via the register.
      // Hence it's normal if for certain compilers or optimization modes
      // --test_register_leak does not cause a leak crash of the above form
      // (this happens e.g. for gcc 4.0.1 in opt mode).
      ptr = reinterpret_cast<int **>(
          reinterpret_cast<uintptr_t>(ptr) ^ kHideMask);
      // busy loop to get the thread interrupted at:
      for (int i = 1; i < 10000000; ++i)  user += (1 + user * user * 5) / i;
      ptr = reinterpret_cast<int **>(
          reinterpret_cast<uintptr_t>(ptr) ^ kHideMask);
    } else {
      poll(NULL, 0, random() % 100);
    }
    VLOG(2) << pthread_self() << ": continuing";
    if (random() % 3 == 0) {
      delete [] *ptr;
      delete [] ptr;
      ptr = NULL;
    }
    delete [] s2;
  }
  return a;
}

static void RunHeapBusyThreads() {
  KeyInit();
  if (!FLAGS_interfering_threads || FLAGS_no_threads)  return;

  const int n = 17;  // make many threads

  pthread_t tid;
  pthread_attr_t attr;
  CHECK_EQ(pthread_attr_init(&attr), 0);
  // make them and let them run
  for (int i = 0; i < n; ++i) {
    VLOG(0) << "Creating extra thread " << i + 1;
    CHECK(pthread_create(&tid, &attr, HeapBusyThreadBody,
                         reinterpret_cast<void*>(i)) == 0);
  }

  Pause();
  Pause();
}

// ========================================================================= //

// This code section is to test that objects that are reachable from global
// variables are not reported as leaks
// as well as that (Un)IgnoreObject work for such objects fine.

// An object making functions:
// returns a "weird" pointer to a new object for which
// it's worth checking that the object is reachable via that pointer.
typedef void* (*ObjMakerFunc)();
static list<ObjMakerFunc> obj_makers;  // list of registered object makers

// Helper macro to register an object making function
// 'name' is an identifier of this object maker,
// 'body' is its function body that must declare
//        pointer 'p' to the nex object to return.
// Usage example:
//   REGISTER_OBJ_MAKER(trivial, int* p = new(initialized) int;)
#define REGISTER_OBJ_MAKER(name, body) \
  void* ObjMaker_##name##_() { \
    VLOG(1) << "Obj making " << #name; \
    body; \
    return p; \
  } \
  static ObjMakerRegistrar maker_reg_##name##__(&ObjMaker_##name##_);
// helper class for REGISTER_OBJ_MAKER
struct ObjMakerRegistrar {
  ObjMakerRegistrar(ObjMakerFunc obj_maker) { obj_makers.push_back(obj_maker); }
};

// List of the objects/pointers made with all the obj_makers
// to test reachability via global data pointers during leak checks.
static list<void*>* live_objects = new list<void*>;
  // pointer so that it does not get destructed on exit

// Exerciser for one ObjMakerFunc.
static void TestPointerReach(ObjMakerFunc obj_maker) {