Add DwarfSection classes.

Bug: 23762183

Test: Ran new unit tests.
Change-Id: Icca2a73c50d467718ba4ac41e1c8f541488620dd
diff --git a/libunwindstack/tests/DwarfSectionTest.cpp b/libunwindstack/tests/DwarfSectionTest.cpp
new file mode 100644
index 0000000..20f0e2a
--- /dev/null
+++ b/libunwindstack/tests/DwarfSectionTest.cpp
@@ -0,0 +1,160 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdint.h>
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include "DwarfSection.h"
+
+#include "MemoryFake.h"
+
+class MockDwarfSection : public DwarfSection {
+ public:
+  MockDwarfSection(Memory* memory) : DwarfSection(memory) {}
+  virtual ~MockDwarfSection() = default;
+
+  MOCK_METHOD4(Log, bool(uint8_t, uint64_t, uint64_t, const DwarfFde*));
+
+  MOCK_METHOD4(Eval, bool(const DwarfCie*, Memory*, const dwarf_loc_regs_t&, Regs*));
+
+  MOCK_METHOD3(GetCfaLocationInfo, bool(uint64_t, const DwarfFde*, dwarf_loc_regs_t*));
+
+  MOCK_METHOD2(Init, bool(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));
+
+  MOCK_METHOD1(AdjustPcFromFde, uint64_t(uint64_t));
+};
+
+class DwarfSectionTest : public ::testing::Test {
+ protected:
+  MemoryFake memory_;
+};
+
+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));
+
+  ASSERT_FALSE(mock_section.Step(0x1000, nullptr, nullptr));
+}
+
+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));
+
+  ASSERT_FALSE(mock_section.Step(0x1000, nullptr, nullptr));
+}
+
+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::_))
+      .WillOnce(::testing::Return(false));
+
+  ASSERT_FALSE(mock_section.Step(0x1000, nullptr, nullptr));
+}
+
+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::_))
+      .WillOnce(::testing::Return(true));
+
+  MemoryFake process;
+  EXPECT_CALL(mock_section, Eval(&cie, &process, ::testing::_, nullptr))
+      .WillOnce(::testing::Return(true));
+
+  ASSERT_TRUE(mock_section.Step(0x1000, nullptr, &process));
+}