Add some unit tests for Linux WriteSymbolFile

src/common/linux/synth_elf.h

Index: src/common/linux/synth_elf.h
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+// -*- mode: C++ -*-
+
+// Copyright (c) 2011, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Original author: Ted Mielczarek <ted.mielczarek@gmail.com>
+
+// synth_elf.h: Interface to synth_elf::ELF: fake ELF generator.
+
+#ifndef COMMON_LINUX_SYNTH_ELF_H_
+#define COMMON_LINUX_SYNTH_ELF_H_
+
+#include "common/test_assembler.h"
+
+#include <list>
+#include <map>
+#include <string>
+#include <utility>
+
+namespace google_breakpad {
+namespace synth_elf {
+
+using std::list;
+using std::map;
+using std::pair;
+using std::string;
+using test_assembler::Endianness;
+using test_assembler::kLittleEndian;
+using test_assembler::kUnsetEndian;
+using test_assembler::Label;
+using test_assembler::Section;
+
+// String tables are common in ELF headers, so subclass Section
+// to make them easy to generate.
+class StringTable : public Section {
+public:
+  StringTable(Endianness endianness = kUnsetEndian)
+  : Section(endianness) {
+    start() = 0;
+    empty_string = Add("");
+  }
+
+  // Add the string s to the string table, and return
+  // a label containing the offset into the string table
+  // at which it was added.
+  Label Add(const string& s) {
+    if (strings_.find(s) != strings_.end())
+      return strings_[s];
+
+    Label string_label(Here());
+    AppendCString(s);
+    strings_[s] = string_label;
+    return string_label;
+  }
+
+  // All StringTables contain an empty string as their first
+  // entry.
+  Label empty_string;
+
+  // Avoid inserting duplicate strings.
+  map<string,Label> strings_;
+};
+
+// A Section representing an entire ELF file.
+class ELF : public Section {
+ public:
+  ELF(uint16_t machine,
+      Endianness endianness = kLittleEndian);
+
+  // Add the Section section to the section header table and append it
+  // to the file. Returns the index of the section in the section
+  // header table.
+  int AddSection(const string& name, const Section& section,
+                 uint32_t type, uint32_t flags = 0, uint64_t addr = 0,
+                 uint32_t link = 0, uint64_t entsize = 0, uint64_t offset = 0);
+                  
+  // Write out all data. GetContents may be used after this.
+  void Finish();
+
+ private:
+  // Size of an address, in bytes.
+  const size_t addr_size_;
+
+  // Offset to the program header table.
+  Label program_header_label_;
+  // Number of entries in the program header table.
+  int program_count_;
+  Label program_count_label_;
+
+  // Offset to the section header table.
+  Label section_header_label_;
+  // Number of entries in the section header table.
+  int section_count_;
+  Label section_count_label_;
+  // The section header table itself.
+  Section section_header_table_;
+
+  // Index of the section header string table in the section
+  // header table.
+  Label section_header_string_index_;
+  // Section containing the names of section header table entries.
+  StringTable section_header_strings_;
+};
+
+// A class to build .symtab or .dynsym sections.
+class SymbolTable : public Section {
+ public:
+  // table is the StringTable that contains symbol names. The caller
+  // must ensure that it remains alive for the life of the
+  // SymbolTable.
+  SymbolTable(Endianness endianness, size_t addr_size, StringTable& table);
+
+  // Add an Elf32_Sym.
+  void AddSymbol(const string& name, uint32_t value,
+                 uint32_t size, unsigned info, uint16_t shndx);
+  // Add an Elf64_Sym.
+  void AddSymbol(const string& name, uint64_t value,
+                 uint64_t size, unsigned info, uint16_t shndx);
+
+ private:
+  size_t addr_size_;
+  StringTable& table_;
+};
+
+}  // namespace synth_elf
+}  // namespace google_breakpad
+
+#endif  // COMMON_LINUX_SYNTH_ELF_H_