1 // Copyright 2017 The Abseil Authors.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include "absl/base/internal/low_level_alloc.h"
16
17 #include <stdint.h>
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <thread> // NOLINT(build/c++11)
21 #include <unordered_map>
22 #include <utility>
23
24 #include "absl/container/node_hash_map.h"
25
26 namespace absl {
27 ABSL_NAMESPACE_BEGIN
28 namespace base_internal {
29 namespace {
30
31 // This test doesn't use gtest since it needs to test that everything
32 // works before main().
33 #define TEST_ASSERT(x) \
34 if (!(x)) { \
35 printf("TEST_ASSERT(%s) FAILED ON LINE %d\n", #x, __LINE__); \
36 abort(); \
37 }
38
39 // a block of memory obtained from the allocator
40 struct BlockDesc {
41 char *ptr; // pointer to memory
42 int len; // number of bytes
43 int fill; // filled with data starting with this
44 };
45
46 // Check that the pattern placed in the block d
47 // by RandomizeBlockDesc is still there.
CheckBlockDesc(const BlockDesc & d)48 static void CheckBlockDesc(const BlockDesc &d) {
49 for (int i = 0; i != d.len; i++) {
50 TEST_ASSERT((d.ptr[i] & 0xff) == ((d.fill + i) & 0xff));
51 }
52 }
53
54 // Fill the block "*d" with a pattern
55 // starting with a random byte.
RandomizeBlockDesc(BlockDesc * d)56 static void RandomizeBlockDesc(BlockDesc *d) {
57 d->fill = rand() & 0xff;
58 for (int i = 0; i != d->len; i++) {
59 d->ptr[i] = (d->fill + i) & 0xff;
60 }
61 }
62
63 // Use to indicate to the malloc hooks that
64 // this calls is from LowLevelAlloc.
65 static bool using_low_level_alloc = false;
66
67 // n times, toss a coin, and based on the outcome
68 // either allocate a new block or deallocate an old block.
69 // New blocks are placed in a std::unordered_map with a random key
70 // and initialized with RandomizeBlockDesc().
71 // If keys conflict, the older block is freed.
72 // Old blocks are always checked with CheckBlockDesc()
73 // before being freed. At the end of the run,
74 // all remaining allocated blocks are freed.
75 // If use_new_arena is true, use a fresh arena, and then delete it.
76 // If call_malloc_hook is true and user_arena is true,
77 // allocations and deallocations are reported via the MallocHook
78 // interface.
Test(bool use_new_arena,bool call_malloc_hook,int n)79 static void Test(bool use_new_arena, bool call_malloc_hook, int n) {
80 typedef absl::node_hash_map<int, BlockDesc> AllocMap;
81 AllocMap allocated;
82 AllocMap::iterator it;
83 BlockDesc block_desc;
84 int rnd;
85 LowLevelAlloc::Arena *arena = 0;
86 if (use_new_arena) {
87 int32_t flags = call_malloc_hook ? LowLevelAlloc::kCallMallocHook : 0;
88 arena = LowLevelAlloc::NewArena(flags);
89 }
90 for (int i = 0; i != n; i++) {
91 if (i != 0 && i % 10000 == 0) {
92 printf(".");
93 fflush(stdout);
94 }
95
96 switch (rand() & 1) { // toss a coin
97 case 0: // coin came up heads: add a block
98 using_low_level_alloc = true;
99 block_desc.len = rand() & 0x3fff;
100 block_desc.ptr =
101 reinterpret_cast<char *>(
102 arena == 0
103 ? LowLevelAlloc::Alloc(block_desc.len)
104 : LowLevelAlloc::AllocWithArena(block_desc.len, arena));
105 using_low_level_alloc = false;
106 RandomizeBlockDesc(&block_desc);
107 rnd = rand();
108 it = allocated.find(rnd);
109 if (it != allocated.end()) {
110 CheckBlockDesc(it->second);
111 using_low_level_alloc = true;
112 LowLevelAlloc::Free(it->second.ptr);
113 using_low_level_alloc = false;
114 it->second = block_desc;
115 } else {
116 allocated[rnd] = block_desc;
117 }
118 break;
119 case 1: // coin came up tails: remove a block
120 it = allocated.begin();
121 if (it != allocated.end()) {
122 CheckBlockDesc(it->second);
123 using_low_level_alloc = true;
124 LowLevelAlloc::Free(it->second.ptr);
125 using_low_level_alloc = false;
126 allocated.erase(it);
127 }
128 break;
129 }
130 }
131 // remove all remaining blocks
132 while ((it = allocated.begin()) != allocated.end()) {
133 CheckBlockDesc(it->second);
134 using_low_level_alloc = true;
135 LowLevelAlloc::Free(it->second.ptr);
136 using_low_level_alloc = false;
137 allocated.erase(it);
138 }
139 if (use_new_arena) {
140 TEST_ASSERT(LowLevelAlloc::DeleteArena(arena));
141 }
142 }
143
144 // LowLevelAlloc is designed to be safe to call before main().
145 static struct BeforeMain {
BeforeMainabsl::base_internal::__anon2e4ad69e0111::BeforeMain146 BeforeMain() {
147 Test(false, false, 50000);
148 Test(true, false, 50000);
149 Test(true, true, 50000);
150 }
151 } before_main;
152
153 } // namespace
154 } // namespace base_internal
155 ABSL_NAMESPACE_END
156 } // namespace absl
157
main(int argc,char * argv[])158 int main(int argc, char *argv[]) {
159 // The actual test runs in the global constructor of `before_main`.
160 printf("PASS\n");
161 return 0;
162 }
163