1 /*
2  * Copyright (C) 2018 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 <vector>
18 
19 #include <android-base/logging.h>
20 #include "dex/compact_offset_table.h"
21 #include "gtest/gtest.h"
22 
23 namespace art {
24 
TEST(CompactOffsetTableTest,TestBuildAndAccess)25 TEST(CompactOffsetTableTest, TestBuildAndAccess) {
26   const size_t kDebugInfoMinOffset = 1234567;
27   std::vector<uint32_t> offsets = {
28       0, 17, 2, 3, 11, 0, 0, 0, 0, 1, 0, 1552, 100, 122, 44, 1234567, 0, 0,
29       std::numeric_limits<uint32_t>::max() - kDebugInfoMinOffset, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
30       0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12,
31   };
32   // Add some large offset since the debug info section will never be that close to the beginning
33   // of the file.
34   for (uint32_t& offset : offsets) {
35     if (offset != 0u) {
36       offset += kDebugInfoMinOffset;
37     }
38   }
39 
40   std::vector<uint8_t> data;
41   uint32_t min_offset = 0;
42   uint32_t table_offset = 0;
43   CompactOffsetTable::Build(offsets, /*out*/ &data, /*out*/ &min_offset, /*out*/ &table_offset);
44   EXPECT_GE(min_offset, kDebugInfoMinOffset);
45   EXPECT_LT(table_offset, data.size());
46   ASSERT_GT(data.size(), 0u);
47   const size_t before_size = offsets.size() * sizeof(offsets.front());
48   EXPECT_LT(data.size(), before_size);
49 
50   // Note that the accessor requires the data to be aligned. Use memmap to accomplish this.
51   std::string error_msg;
52   // Leave some extra room since we don't copy the table at the start (for testing).
53   constexpr size_t kExtraOffset = 4 * 128;
54   std::vector<uint8_t> fake_dex(data.size() + kExtraOffset);
55   std::copy(data.begin(), data.end(), fake_dex.data() + kExtraOffset);
56 
57   CompactOffsetTable::Accessor accessor(fake_dex.data() + kExtraOffset, min_offset, table_offset);
58   for (size_t i = 0; i < offsets.size(); ++i) {
59     EXPECT_EQ(offsets[i], accessor.GetOffset(i));
60   }
61 
62   // Sort to produce a try and produce a smaller table. This happens because the leb diff is smaller
63   // for sorted increasing order.
64   std::sort(offsets.begin(), offsets.end());
65   std::vector<uint8_t> sorted_data;
66   CompactOffsetTable::Build(offsets,
67                             /*out*/ &sorted_data,
68                             /*out*/ &min_offset,
69                             /*out*/ &table_offset);
70   EXPECT_LT(sorted_data.size(), data.size());
71   {
72     android::base::ScopedLogSeverity sls(android::base::LogSeverity::INFO);
73     LOG(INFO) << "raw size " << before_size
74               << " table size " << data.size()
75               << " sorted table size " << sorted_data.size();
76   }
77 
78   // Test constructor and accessor that serialize/read offsets.
79   {
80     std::vector<uint8_t> data2;
81     CompactOffsetTable::Build(offsets, /*out*/ &data2);
82     CompactOffsetTable::Accessor accessor2(&data2[0]);
83     for (size_t i = 0; i < offsets.size(); ++i) {
84       EXPECT_EQ(offsets[i], accessor2.GetOffset(i));
85     }
86   }
87 }
88 
89 }  // namespace art
90