Refactor the DwarfSection classes.

Modify the code for the no header sections because it turns out that
it is not okay to assume that the fdes are non-overlapping. It's necessary
to read the fdes in order and match as you go.

Modify the code so that it only reads until it finds the given pc rather than
reading all of the cie/fde entries at once.

Rewrote the tests to verify the new behavior.

Bug: 68998033
Bug: 110235461

Test: Ran libbacktrace/libunwindstack unit tests.
Test: Unwind the mediaserver process on a walleye and verify it
Test: unwinds properly.

Change-Id: I7bb59d1db72c13fa34caa9735ec34c1a60e20ed2
diff --git a/libunwindstack/tests/DwarfSectionTest.cpp b/libunwindstack/tests/DwarfSectionTest.cpp
index 2c6c879..d754fcc 100644
--- a/libunwindstack/tests/DwarfSectionTest.cpp
+++ b/libunwindstack/tests/DwarfSectionTest.cpp
@@ -30,24 +30,18 @@
   MockDwarfSection(Memory* memory) : DwarfSection(memory) {}
   virtual ~MockDwarfSection() = default;
 
-  MOCK_METHOD3(Log, bool(uint8_t, uint64_t, const DwarfFde*));
+  MOCK_METHOD3(Init, bool(uint64_t, uint64_t, uint64_t));
 
   MOCK_METHOD5(Eval, bool(const DwarfCie*, Memory*, const dwarf_loc_regs_t&, Regs*, bool*));
 
+  MOCK_METHOD3(Log, bool(uint8_t, uint64_t, const DwarfFde*));
+
+  MOCK_METHOD1(GetFdes, void(std::vector<const DwarfFde*>*));
+
+  MOCK_METHOD1(GetFdeFromPc, const DwarfFde*(uint64_t));
+
   MOCK_METHOD3(GetCfaLocationInfo, bool(uint64_t, const DwarfFde*, dwarf_loc_regs_t*));
 
-  MOCK_METHOD3(Init, bool(uint64_t, uint64_t, uint64_t));
-
-  MOCK_METHOD2(GetFdeOffsetFromPc, bool(uint64_t, uint64_t*));
-
-  MOCK_METHOD1(GetFdeFromOffset, const DwarfFde*(uint64_t));
-
-  MOCK_METHOD1(GetFdeFromIndex, const DwarfFde*(size_t));
-
-  MOCK_METHOD1(IsCie32, bool(uint32_t));
-
-  MOCK_METHOD1(IsCie64, bool(uint64_t));
-
   MOCK_METHOD1(GetCieOffsetFromFde32, uint64_t(uint32_t));
 
   MOCK_METHOD1(GetCieOffsetFromFde64, uint64_t(uint64_t));
@@ -57,112 +51,60 @@
 
 class DwarfSectionTest : public ::testing::Test {
  protected:
+  void SetUp() override { section_.reset(new MockDwarfSection(&memory_)); }
+
   MemoryFake memory_;
+  std::unique_ptr<MockDwarfSection> section_;
 };
 
-TEST_F(DwarfSectionTest, GetFdeOffsetFromPc_fail_from_pc) {
-  MockDwarfSection mock_section(&memory_);
-
-  EXPECT_CALL(mock_section, GetFdeOffsetFromPc(0x1000, ::testing::_))
-      .WillOnce(::testing::Return(false));
-
-  // Verify nullptr when GetFdeOffsetFromPc fails.
-  ASSERT_TRUE(mock_section.GetFdeFromPc(0x1000) == nullptr);
-}
-
-TEST_F(DwarfSectionTest, GetFdeOffsetFromPc_fail_fde_pc_end) {
-  MockDwarfSection mock_section(&memory_);
-
-  DwarfFde fde{};
-  fde.pc_end = 0x500;
-
-  EXPECT_CALL(mock_section, GetFdeOffsetFromPc(0x1000, ::testing::_))
-      .WillOnce(::testing::Return(true));
-  EXPECT_CALL(mock_section, GetFdeFromOffset(::testing::_)).WillOnce(::testing::Return(&fde));
-
-  // Verify nullptr when GetFdeOffsetFromPc fails.
-  ASSERT_TRUE(mock_section.GetFdeFromPc(0x1000) == nullptr);
-}
-
-TEST_F(DwarfSectionTest, GetFdeOffsetFromPc_pass) {
-  MockDwarfSection mock_section(&memory_);
-
-  DwarfFde fde{};
-  fde.pc_end = 0x2000;
-
-  EXPECT_CALL(mock_section, GetFdeOffsetFromPc(0x1000, ::testing::_))
-      .WillOnce(::testing::Return(true));
-  EXPECT_CALL(mock_section, GetFdeFromOffset(::testing::_)).WillOnce(::testing::Return(&fde));
-
-  // Verify nullptr when GetFdeOffsetFromPc fails.
-  ASSERT_EQ(&fde, mock_section.GetFdeFromPc(0x1000));
-}
-
 TEST_F(DwarfSectionTest, Step_fail_fde) {
-  MockDwarfSection mock_section(&memory_);
-
-  EXPECT_CALL(mock_section, GetFdeOffsetFromPc(0x1000, ::testing::_))
-      .WillOnce(::testing::Return(false));
+  EXPECT_CALL(*section_, GetFdeFromPc(0x1000)).WillOnce(::testing::Return(nullptr));
 
   bool finished;
-  ASSERT_FALSE(mock_section.Step(0x1000, nullptr, nullptr, &finished));
+  ASSERT_FALSE(section_->Step(0x1000, nullptr, nullptr, &finished));
 }
 
 TEST_F(DwarfSectionTest, Step_fail_cie_null) {
-  MockDwarfSection mock_section(&memory_);
-
   DwarfFde fde{};
   fde.pc_end = 0x2000;
   fde.cie = nullptr;
 
-  EXPECT_CALL(mock_section, GetFdeOffsetFromPc(0x1000, ::testing::_))
-      .WillOnce(::testing::Return(true));
-  EXPECT_CALL(mock_section, GetFdeFromOffset(::testing::_)).WillOnce(::testing::Return(&fde));
+  EXPECT_CALL(*section_, GetFdeFromPc(0x1000)).WillOnce(::testing::Return(&fde));
 
   bool finished;
-  ASSERT_FALSE(mock_section.Step(0x1000, nullptr, nullptr, &finished));
+  ASSERT_FALSE(section_->Step(0x1000, nullptr, nullptr, &finished));
 }
 
 TEST_F(DwarfSectionTest, Step_fail_cfa_location) {
-  MockDwarfSection mock_section(&memory_);
-
   DwarfCie cie{};
   DwarfFde fde{};
   fde.pc_end = 0x2000;
   fde.cie = &cie;
 
-  EXPECT_CALL(mock_section, GetFdeOffsetFromPc(0x1000, ::testing::_))
-      .WillOnce(::testing::Return(true));
-  EXPECT_CALL(mock_section, GetFdeFromOffset(::testing::_)).WillOnce(::testing::Return(&fde));
-
-  EXPECT_CALL(mock_section, GetCfaLocationInfo(0x1000, &fde, ::testing::_))
+  EXPECT_CALL(*section_, GetFdeFromPc(0x1000)).WillOnce(::testing::Return(&fde));
+  EXPECT_CALL(*section_, GetCfaLocationInfo(0x1000, &fde, ::testing::_))
       .WillOnce(::testing::Return(false));
 
   bool finished;
-  ASSERT_FALSE(mock_section.Step(0x1000, nullptr, nullptr, &finished));
+  ASSERT_FALSE(section_->Step(0x1000, nullptr, nullptr, &finished));
 }
 
 TEST_F(DwarfSectionTest, Step_pass) {
-  MockDwarfSection mock_section(&memory_);
-
   DwarfCie cie{};
   DwarfFde fde{};
   fde.pc_end = 0x2000;
   fde.cie = &cie;
 
-  EXPECT_CALL(mock_section, GetFdeOffsetFromPc(0x1000, ::testing::_))
-      .WillOnce(::testing::Return(true));
-  EXPECT_CALL(mock_section, GetFdeFromOffset(::testing::_)).WillOnce(::testing::Return(&fde));
-
-  EXPECT_CALL(mock_section, GetCfaLocationInfo(0x1000, &fde, ::testing::_))
+  EXPECT_CALL(*section_, GetFdeFromPc(0x1000)).WillOnce(::testing::Return(&fde));
+  EXPECT_CALL(*section_, GetCfaLocationInfo(0x1000, &fde, ::testing::_))
       .WillOnce(::testing::Return(true));
 
   MemoryFake process;
-  EXPECT_CALL(mock_section, Eval(&cie, &process, ::testing::_, nullptr, ::testing::_))
+  EXPECT_CALL(*section_, Eval(&cie, &process, ::testing::_, nullptr, ::testing::_))
       .WillOnce(::testing::Return(true));
 
   bool finished;
-  ASSERT_TRUE(mock_section.Step(0x1000, nullptr, &process, &finished));
+  ASSERT_TRUE(section_->Step(0x1000, nullptr, &process, &finished));
 }
 
 static bool MockGetCfaLocationInfo(::testing::Unused, const DwarfFde* fde,
@@ -173,64 +115,53 @@
 }
 
 TEST_F(DwarfSectionTest, Step_cache) {
-  MockDwarfSection mock_section(&memory_);
-
   DwarfCie cie{};
   DwarfFde fde{};
   fde.pc_start = 0x500;
   fde.pc_end = 0x2000;
   fde.cie = &cie;
 
-  EXPECT_CALL(mock_section, GetFdeOffsetFromPc(0x1000, ::testing::_))
-      .WillOnce(::testing::Return(true));
-  EXPECT_CALL(mock_section, GetFdeFromOffset(::testing::_)).WillOnce(::testing::Return(&fde));
-
-  EXPECT_CALL(mock_section, GetCfaLocationInfo(0x1000, &fde, ::testing::_))
+  EXPECT_CALL(*section_, GetFdeFromPc(0x1000)).WillOnce(::testing::Return(&fde));
+  EXPECT_CALL(*section_, GetCfaLocationInfo(0x1000, &fde, ::testing::_))
       .WillOnce(::testing::Invoke(MockGetCfaLocationInfo));
 
   MemoryFake process;
-  EXPECT_CALL(mock_section, Eval(&cie, &process, ::testing::_, nullptr, ::testing::_))
+  EXPECT_CALL(*section_, Eval(&cie, &process, ::testing::_, nullptr, ::testing::_))
       .WillRepeatedly(::testing::Return(true));
 
   bool finished;
-  ASSERT_TRUE(mock_section.Step(0x1000, nullptr, &process, &finished));
-  ASSERT_TRUE(mock_section.Step(0x1000, nullptr, &process, &finished));
-  ASSERT_TRUE(mock_section.Step(0x1500, nullptr, &process, &finished));
+  ASSERT_TRUE(section_->Step(0x1000, nullptr, &process, &finished));
+  ASSERT_TRUE(section_->Step(0x1000, nullptr, &process, &finished));
+  ASSERT_TRUE(section_->Step(0x1500, nullptr, &process, &finished));
 }
 
 TEST_F(DwarfSectionTest, Step_cache_not_in_pc) {
-  MockDwarfSection mock_section(&memory_);
-
   DwarfCie cie{};
   DwarfFde fde0{};
   fde0.pc_start = 0x1000;
   fde0.pc_end = 0x2000;
   fde0.cie = &cie;
-  EXPECT_CALL(mock_section, GetFdeOffsetFromPc(0x1000, ::testing::_))
-      .WillOnce(::testing::Return(true));
-  EXPECT_CALL(mock_section, GetFdeFromOffset(::testing::_)).WillOnce(::testing::Return(&fde0));
-  EXPECT_CALL(mock_section, GetCfaLocationInfo(0x1000, &fde0, ::testing::_))
+  EXPECT_CALL(*section_, GetFdeFromPc(0x1000)).WillOnce(::testing::Return(&fde0));
+  EXPECT_CALL(*section_, GetCfaLocationInfo(0x1000, &fde0, ::testing::_))
       .WillOnce(::testing::Invoke(MockGetCfaLocationInfo));
 
   MemoryFake process;
-  EXPECT_CALL(mock_section, Eval(&cie, &process, ::testing::_, nullptr, ::testing::_))
+  EXPECT_CALL(*section_, Eval(&cie, &process, ::testing::_, nullptr, ::testing::_))
       .WillRepeatedly(::testing::Return(true));
 
   bool finished;
-  ASSERT_TRUE(mock_section.Step(0x1000, nullptr, &process, &finished));
+  ASSERT_TRUE(section_->Step(0x1000, nullptr, &process, &finished));
 
   DwarfFde fde1{};
   fde1.pc_start = 0x500;
   fde1.pc_end = 0x800;
   fde1.cie = &cie;
-  EXPECT_CALL(mock_section, GetFdeOffsetFromPc(0x600, ::testing::_))
-      .WillOnce(::testing::Return(true));
-  EXPECT_CALL(mock_section, GetFdeFromOffset(::testing::_)).WillOnce(::testing::Return(&fde1));
-  EXPECT_CALL(mock_section, GetCfaLocationInfo(0x600, &fde1, ::testing::_))
+  EXPECT_CALL(*section_, GetFdeFromPc(0x600)).WillOnce(::testing::Return(&fde1));
+  EXPECT_CALL(*section_, GetCfaLocationInfo(0x600, &fde1, ::testing::_))
       .WillOnce(::testing::Invoke(MockGetCfaLocationInfo));
 
-  ASSERT_TRUE(mock_section.Step(0x600, nullptr, &process, &finished));
-  ASSERT_TRUE(mock_section.Step(0x700, nullptr, &process, &finished));
+  ASSERT_TRUE(section_->Step(0x600, nullptr, &process, &finished));
+  ASSERT_TRUE(section_->Step(0x700, nullptr, &process, &finished));
 }
 
 }  // namespace unwindstack