Turn symbol_inject into a reusable package

Bug: 31559095
Test: m blueprint_tools
Change-Id: I0f7a9f14111af26d753db547c6de313a7079658a
diff --git a/symbol_inject/pe_test.go b/symbol_inject/pe_test.go
new file mode 100644
index 0000000..df7bac3
--- /dev/null
+++ b/symbol_inject/pe_test.go
@@ -0,0 +1,141 @@
+// Copyright 2018 Google Inc. All rights reserved.
+//
+// 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.
+
+package symbol_inject
+
+import (
+	"debug/pe"
+	"strconv"
+	"testing"
+)
+
+func TestPESymbolTable(t *testing.T) {
+	testCases := []struct {
+		file         *pe.File
+		symbol       string
+		offset, size uint64
+	}{
+		{
+			file:   peSymbolTable1,
+			symbol: "soong_build_number",
+			offset: 0x2420,
+			size:   128,
+		},
+		{
+			file:   peSymbolTable2,
+			symbol: "symbol1",
+			offset: 0x2420,
+			size:   128,
+		},
+		{
+			file:   peSymbolTable2,
+			symbol: "symbol2",
+			offset: 0x24a0,
+			size:   128,
+		},
+		{
+			// Test when symbol has the same value as the target symbol but is located afterwards in the list
+			file: &pe.File{
+				FileHeader: pe.FileHeader{
+					Machine: pe.IMAGE_FILE_MACHINE_I386,
+				},
+				Sections: []*pe.Section{
+					&pe.Section{SectionHeader: pe.SectionHeader{Name: ".text", VirtualSize: 0x15e83c, VirtualAddress: 0x1000, Size: 0x15ea00, Offset: 0x600, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x60500060}},
+					&pe.Section{SectionHeader: pe.SectionHeader{Name: ".data", VirtualSize: 0x6a58, VirtualAddress: 0x160000, Size: 0x6c00, Offset: 0x15f000, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0xc0600040}},
+				},
+				Symbols: []*pe.Symbol{
+					&pe.Symbol{Name: "_soong_build_number", Value: 0x20, SectionNumber: 2, Type: 0x0, StorageClass: 0x2},
+					&pe.Symbol{Name: ".data", Value: 0x20, SectionNumber: 2, Type: 0x0, StorageClass: 0x3},
+					&pe.Symbol{Name: "_adb_device_banner", Value: 0xa0, SectionNumber: 2, Type: 0x0, StorageClass: 0x2},
+				},
+			},
+			symbol: "soong_build_number",
+			offset: 0x15f020,
+			size:   128,
+		},
+		{
+			// Test when symbol has nothing after it
+			file: &pe.File{
+				FileHeader: pe.FileHeader{
+					Machine: pe.IMAGE_FILE_MACHINE_AMD64,
+				},
+				Sections: []*pe.Section{
+					&pe.Section{SectionHeader: pe.SectionHeader{Name: ".text", VirtualSize: 0x1cc0, VirtualAddress: 0x1000, Size: 0x1e00, Offset: 0x600, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x60500020}},
+					&pe.Section{SectionHeader: pe.SectionHeader{Name: ".data", VirtualSize: 0xa0, VirtualAddress: 0x3000, Size: 0x200, Offset: 0x2400, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0xc0600040}},
+				},
+				Symbols: []*pe.Symbol{
+					&pe.Symbol{Name: "soong_build_number", Value: 0x20, SectionNumber: 2, Type: 0x0, StorageClass: 0x2},
+				},
+			},
+			symbol: "soong_build_number",
+			offset: 0x2420,
+			size:   128,
+		},
+		{
+			// Test when symbol has a symbol in a different section after it
+			file: &pe.File{
+				FileHeader: pe.FileHeader{
+					Machine: pe.IMAGE_FILE_MACHINE_AMD64,
+				},
+				Sections: []*pe.Section{
+					&pe.Section{SectionHeader: pe.SectionHeader{Name: ".text", VirtualSize: 0x1cc0, VirtualAddress: 0x1000, Size: 0x1e00, Offset: 0x600, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x60500020}},
+					&pe.Section{SectionHeader: pe.SectionHeader{Name: ".data", VirtualSize: 0xa0, VirtualAddress: 0x3000, Size: 0x200, Offset: 0x2400, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0xc0600040}},
+					&pe.Section{SectionHeader: pe.SectionHeader{Name: ".rdata", VirtualSize: 0x5e0, VirtualAddress: 0x4000, Size: 0x600, Offset: 0x2600, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x40500040}},
+				},
+				Symbols: []*pe.Symbol{
+					&pe.Symbol{Name: "soong_build_number", Value: 0x20, SectionNumber: 2, Type: 0x0, StorageClass: 0x2},
+					&pe.Symbol{Name: "_adb_device_banner", Value: 0x30, SectionNumber: 3, Type: 0x0, StorageClass: 0x2},
+				},
+			},
+			symbol: "soong_build_number",
+			offset: 0x2420,
+			size:   128,
+		},
+		{
+			// Test when symbols are out of order
+			file: &pe.File{
+				FileHeader: pe.FileHeader{
+					Machine: pe.IMAGE_FILE_MACHINE_AMD64,
+				},
+				Sections: []*pe.Section{
+					&pe.Section{SectionHeader: pe.SectionHeader{Name: ".text", VirtualSize: 0x1cc0, VirtualAddress: 0x1000, Size: 0x1e00, Offset: 0x600, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x60500020}},
+					&pe.Section{SectionHeader: pe.SectionHeader{Name: ".data", VirtualSize: 0x120, VirtualAddress: 0x3000, Size: 0x200, Offset: 0x2400, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0xc0600040}},
+				},
+				Symbols: []*pe.Symbol{
+					&pe.Symbol{Name: "_adb_device_banner", Value: 0xa0, SectionNumber: 2, Type: 0x0, StorageClass: 0x2},
+					&pe.Symbol{Name: "soong_build_number", Value: 0x20, SectionNumber: 2, Type: 0x0, StorageClass: 0x2},
+				},
+			},
+			symbol: "soong_build_number",
+			offset: 0x2420,
+			size:   128,
+		},
+	}
+
+	for i, testCase := range testCases {
+		t.Run(strconv.Itoa(i), func(t *testing.T) {
+			file, err := extractPESymbols(testCase.file)
+			if err != nil {
+				t.Error(err.Error())
+			}
+			offset, size, err := findSymbol(file, testCase.symbol)
+			if err != nil {
+				t.Error(err.Error())
+			}
+			if offset != testCase.offset || size != testCase.size {
+				t.Errorf("expected %x:%x, got %x:%x", testCase.offset, testCase.size, offset, size)
+			}
+		})
+	}
+}