Prefetch the native library from native code by parsing /proc/pid/maps.

base/android/library_loader/library_prefetcher_unittest.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/android/library_loader/library_prefetcher.h"
+
+#include <string>
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace base {
+namespace android {
+
+class ProcMapsIteratorTest : public NativeLibraryPrefetcher {
+  class FakeFileLineIterator
+      : public NativeLibraryPrefetcher::FileLineIterator {
+   public:
+    FakeFileLineIterator(const char* lines[]) : lines_(lines), index_(0) {}
+
+    virtual bool NextLine(std::string* line) override {
+      const char* line_str = lines_[index_++];
+      if (!line_str)
+        return false;
+      *line = std::string(line_str);
+      return true;
+    }
+
+   private:
+    const char* const* lines_;
+    size_t index_;
+  };
+
+  FRIEND_TEST_ALL_PREFIXES(ProcMapsIteratorTest, TestParseLine32Bits);
+  FRIEND_TEST_ALL_PREFIXES(ProcMapsIteratorTest, TestParseLine64Bits);
+  FRIEND_TEST_ALL_PREFIXES(ProcMapsIteratorTest, TestParseLineNoFile);
+  FRIEND_TEST_ALL_PREFIXES(ProcMapsIteratorTest, TestFindRangeNoRange);
+  FRIEND_TEST_ALL_PREFIXES(ProcMapsIteratorTest,
+                           TestFindRangeSkipUnreadableRange);
+  FRIEND_TEST_ALL_PREFIXES(ProcMapsIteratorTest, TestFindRangeSkipSharedRange);
+  FRIEND_TEST_ALL_PREFIXES(ProcMapsIteratorTest,
+                           TestFindRangeFindLibChromeRange);
+  FRIEND_TEST_ALL_PREFIXES(ProcMapsIteratorTest,
+                           TestFindRangeFindBaseApkRanges);
+};
+
+TEST(ProcMapsIteratorTest, TestParseLine32Bits) {
+  const char* lines[] = {
+      "b6e62000-b6e64000 r-xp 00000000 b3:15 1204   /lib/libstdc++.so\n",
+      nullptr};
+  ProcMapsIteratorTest::FakeFileLineIterator file_line_iterator(lines);
+  NativeLibraryPrefetcher::ProcMapsIterator maps_iterator(&file_line_iterator);
+  NativeLibraryPrefetcher::ProcMapsIterator::Mapping mapping;
+  ASSERT_TRUE(maps_iterator.Next(&mapping));
+  EXPECT_EQ(mapping.start, 0xb6e62000ULL);
+  EXPECT_EQ(mapping.end, 0xb6e64000ULL);
+  EXPECT_EQ(mapping.flags, "r-xp");
+  EXPECT_EQ(mapping.offset, 0ULL);
+  EXPECT_EQ(mapping.device, "b3:15");
+  EXPECT_EQ(mapping.inode, 1204LL);
+  EXPECT_EQ(mapping.filename, "/lib/libstdc++.so");
+  ASSERT_FALSE(maps_iterator.Next(&mapping));
+}
+
+TEST(ProcMapsIteratorTest, TestParseLine64Bits) {
+  const char* lines[] = {
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 libstdc++.so\n",
+      nullptr};
+  ProcMapsIteratorTest::FakeFileLineIterator file_line_iterator(lines);
+  NativeLibraryPrefetcher::ProcMapsIterator maps_iterator(&file_line_iterator);
+  NativeLibraryPrefetcher::ProcMapsIterator::Mapping mapping;
+  ASSERT_TRUE(maps_iterator.Next(&mapping));
+  EXPECT_EQ(mapping.start, 0x800000b6e62000ULL);
+  EXPECT_EQ(mapping.end, 0x800000b6e64000ULL);
+  EXPECT_EQ(mapping.flags, "r-xp");
+  EXPECT_EQ(mapping.offset, 0ULL);
+  EXPECT_EQ(mapping.device, "b3:15");
+  EXPECT_EQ(mapping.inode, 1204LL);
+  EXPECT_EQ(mapping.filename, "libstdc++.so");
+  ASSERT_FALSE(maps_iterator.Next(&mapping));
+}
+
+TEST(ProcMapsIteratorTest, TestParseLineNoFile) {
+  const char* lines[] = {"b6e62000-b6e64000 r-xp 00000000 b3:15 1204 \n",
+                         nullptr};
+  ProcMapsIteratorTest::FakeFileLineIterator file_line_iterator(lines);
+  NativeLibraryPrefetcher::ProcMapsIterator maps_iterator(&file_line_iterator);
+  NativeLibraryPrefetcher::ProcMapsIterator::Mapping mapping;
+  ASSERT_TRUE(maps_iterator.Next(&mapping));
+  EXPECT_EQ(mapping.start, 0xb6e62000ULL);
+  EXPECT_EQ(mapping.end, 0xb6e64000ULL);
+  EXPECT_EQ(mapping.flags, "r-xp");
+  EXPECT_EQ(mapping.offset, 0ULL);
+  EXPECT_EQ(mapping.device, "b3:15");
+  EXPECT_EQ(mapping.inode, 1204LL);
+  EXPECT_EQ(mapping.filename, "");
+  ASSERT_FALSE(maps_iterator.Next(&mapping));
+}
+
+TEST(ProcMapsIteratorTest, TestFindRangeNoRange) {
+  const char* lines[] = {
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 \n",
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 foo\n",
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 foobar.apk\n",
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 libchromium.so\n",
+      nullptr};
+  ProcMapsIteratorTest::FakeFileLineIterator file_line_iterator(lines);
+  NativeLibraryPrefetcher::ProcMapsIterator maps_iterator(&file_line_iterator);
+  std::vector<std::pair<uint64_t, uint64_t>> ranges =
+      NativeLibraryPrefetcher::ProcMapsIterator::FindRanges(
+          &file_line_iterator);
+  EXPECT_EQ(ranges.size(), 0ULL);
+}
+
+TEST(ProcMapsIteratorTest, TestFindRangeSkipUnreadableRange) {
+  const char* lines[] = {
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 \n",
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 foo\n",
+      "800000b6e62000-800000b6e64000 --xp 00000000 b3:15 1204 base.apk\n",
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 libchromium.so\n",
+      nullptr};
+  ProcMapsIteratorTest::FakeFileLineIterator file_line_iterator(lines);
+  NativeLibraryPrefetcher::ProcMapsIterator maps_iterator(&file_line_iterator);
+  std::vector<std::pair<uint64_t, uint64_t>> ranges =
+      NativeLibraryPrefetcher::ProcMapsIterator::FindRanges(
+          &file_line_iterator);
+  EXPECT_EQ(ranges.size(), 0ULL);
+}
+
+TEST(ProcMapsIteratorTest, TestFindRangeSkipSharedRange) {
+  const char* lines[] = {
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 \n",
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 foo\n",
+      "800000b6e62000-800000b6e64000 r-xs 00000000 b3:15 1204 base.apk\n",
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 libchromium.so\n",
+      nullptr};
+  ProcMapsIteratorTest::FakeFileLineIterator file_line_iterator(lines);
+  NativeLibraryPrefetcher::ProcMapsIterator maps_iterator(&file_line_iterator);
+  std::vector<std::pair<uint64_t, uint64_t>> ranges =
+      NativeLibraryPrefetcher::ProcMapsIterator::FindRanges(
+          &file_line_iterator);
+  EXPECT_EQ(ranges.size(), 0ULL);
+}
+
+TEST(ProcMapsIteratorTest, TestFindRangeFindLibChromeRange) {
+  const char* lines[] = {
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 \n",
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 foo\n",
+      "800000b6e62000-800000b6e64000 --xp 00000000 b3:15 1204 base-ish.apk\n",
+      "42-43 r-xp 00000000 b3:15 42 libchrome.so\n",
+      nullptr};
+  ProcMapsIteratorTest::FakeFileLineIterator file_line_iterator(lines);
+  NativeLibraryPrefetcher::ProcMapsIterator maps_iterator(&file_line_iterator);
+  std::vector<std::pair<uint64_t, uint64_t>> ranges =
+      NativeLibraryPrefetcher::ProcMapsIterator::FindRanges(
+          &file_line_iterator);
+  EXPECT_EQ(ranges.size(), 1ULL);
+  EXPECT_EQ(ranges[0].first, 0x42ULL);
+  EXPECT_EQ(ranges[0].second, 0x43ULL);
+}
+
+TEST(ProcMapsIteratorTest, TestFindRangeFindBaseApkRanges) {
+  const char* lines[] = {
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 \n",
+      "800000b6e62000-800000b6e64000 r-xp 00000000 b3:15 1204 foo\n",
+      "42-43 rw-p 00000000 b3:15 1204 base.apk\n",
+      "64-1000 r-xp 00000000 b3:15 42 base.apk\n",
+      nullptr};
+  ProcMapsIteratorTest::FakeFileLineIterator file_line_iterator(lines);
+  NativeLibraryPrefetcher::ProcMapsIterator maps_iterator(&file_line_iterator);
+  std::vector<std::pair<uint64_t, uint64_t>> ranges =
+      NativeLibraryPrefetcher::ProcMapsIterator::FindRanges(
+          &file_line_iterator);
+  EXPECT_EQ(ranges.size(), 2ULL);
+  EXPECT_EQ(ranges[0].first, 0x42ULL);
+  EXPECT_EQ(ranges[0].second, 0x43ULL);
+  EXPECT_EQ(ranges[1].first, 0x64ULL);
+  EXPECT_EQ(ranges[1].second, 0x1000ULL);
+}
+
+}  // namespace android
+}  // namespace base