Update from https://crrev.com/333737

third_party/android_crazy_linker/src/src/crazy_linker_elf_relocations.h

+// Copyright 2014 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.
+
+#ifndef CRAZY_LINKER_ELF_RELOCATIONS_H
+#define CRAZY_LINKER_ELF_RELOCATIONS_H
+
+#include <string.h>
+#include <unistd.h>
+
+#include "elf_traits.h"
+
+namespace crazy {
+
+class ElfSymbols;
+class ElfView;
+class Error;
+
+// An ElfRelocations instance holds information about relocations in a mapped
+// ELF binary.
+class ElfRelocations {
+ public:
+  ElfRelocations() { ::memset(this, 0, sizeof(*this)); }
+  ~ElfRelocations() {}
+
+  bool Init(const ElfView* view, Error* error);
+
+  // Abstract class used to resolve symbol names into addresses.
+  // Callers of ::ApplyAll() should pass the address of a derived class
+  // that properly implements the Lookup() method.
+  class SymbolResolver {
+   public:
+    SymbolResolver() {}
+    ~SymbolResolver() {}
+    virtual void* Lookup(const char* symbol_name) = 0;
+  };
+
+  // Apply all relocations to the target mapped ELF binary. Must be called
+  // after Init().
+  // |symbols| maps to the symbol entries for the target library only.
+  // |resolver| can resolve symbols out of the current library.
+  // On error, return false and set |error| message.
+  bool ApplyAll(const ElfSymbols* symbols,
+                SymbolResolver* resolver,
+                Error* error);
+
+  // This function is used to adjust relocated addresses in a copy of an
+  // existing section of an ELF binary. I.e. |src_addr|...|src_addr + size|
+  // must be inside the mapped ELF binary, this function will first copy its
+  // content into |dst_addr|...|dst_addr + size|, then adjust all relocated
+  // addresses inside the destination section as if it was loaded/mapped
+  // at |map_addr|...|map_addr + size|. Only relative relocations are processed,
+  // symbolic ones are ignored.
+  void CopyAndRelocate(size_t src_addr,
+                       size_t dst_addr,
+                       size_t map_addr,
+                       size_t size);
+
+ private:
+  bool ResolveSymbol(unsigned rel_type,
+                     unsigned rel_symbol,
+                     const ElfSymbols* symbols,
+                     SymbolResolver* resolver,
+                     ELF::Addr reloc,
+                     ELF::Addr* sym_addr,
+                     Error* error);
+  bool ApplyResolvedRelaReloc(const ELF::Rela* rela,
+                              ELF::Addr sym_addr,
+                              bool resolved,
+                              Error* error);
+  bool ApplyResolvedRelReloc(const ELF::Rel* rel,
+                             ELF::Addr sym_addr,
+                             bool resolved,
+                             Error* error);
+  bool ApplyRelaReloc(const ELF::Rela* rela,
+                      const ElfSymbols* symbols,
+                      SymbolResolver* resolver,
+                      Error* error);
+  bool ApplyRelReloc(const ELF::Rel* rel,
+                     const ElfSymbols* symbols,
+                     SymbolResolver* resolver,
+                     Error* error);
+  bool ApplyRelaRelocs(const ELF::Rela* relocs,
+                       size_t relocs_count,
+                       const ElfSymbols* symbols,
+                       SymbolResolver* resolver,
+                       Error* error);
+  bool ApplyRelRelocs(const ELF::Rel* relocs,
+                      size_t relocs_count,
+                      const ElfSymbols* symbols,
+                      SymbolResolver* resolver,
+                      Error* error);
+  void AdjustRelocation(ELF::Word rel_type,
+                        ELF::Addr src_reloc,
+                        size_t dst_delta,
+                        size_t map_delta);
+  template<typename Rel>
+  void RelocateRelocations(size_t src_addr,
+                          size_t dst_addr,
+                          size_t map_addr,
+                          size_t size);
+  void AdjustAndroidRelocation(const ELF::Rela* relocation,
+                               size_t src_addr,
+                               size_t dst_addr,
+                               size_t map_addr,
+                               size_t size);
+
+  // Android packed relocations unpacker. Calls the given handler for
+  // each relocation in the unpacking stream.
+  typedef bool (*RelocationHandler)(ElfRelocations* relocations,
+                                    const ELF::Rela* relocation,
+                                    void* opaque);
+  bool ForEachAndroidRelocation(RelocationHandler handler,
+                                void* opaque);
+
+  // Apply Android packed relocations.
+  // On error, return false and set |error| message.
+  // The static function is the ForEachAndroidRelocation() handler.
+  bool ApplyAndroidRelocations(const ElfSymbols* symbols,
+                               SymbolResolver* resolver,
+                               Error* error);
+  static bool ApplyAndroidRelocation(ElfRelocations* relocations,
+                                     const ELF::Rela* relocation,
+                                     void* opaque);
+
+  // Relocate Android packed relocations.
+  // The static function is the ForEachAndroidRelocation() handler.
+  void RelocateAndroidRelocations(size_t src_addr,
+                                  size_t dst_addr,
+                                  size_t map_addr,
+                                  size_t size);
+  static bool RelocateAndroidRelocation(ElfRelocations* relocations,
+                                        const ELF::Rela* relocation,
+                                        void* opaque);
+
+#if defined(__mips__)
+  bool RelocateMipsGot(const ElfSymbols* symbols,
+                       SymbolResolver* resolver,
+                       Error* error);
+#endif
+
+  const ELF::Phdr* phdr_;
+  size_t phdr_count_;
+  size_t load_bias_;
+
+  ELF::Addr relocations_type_;
+  ELF::Addr plt_relocations_;
+  size_t plt_relocations_size_;
+  ELF::Addr* plt_got_;
+
+  ELF::Addr relocations_;
+  size_t relocations_size_;
+
+#if defined(__mips__)
+  // MIPS-specific relocation fields.
+  ELF::Word mips_symtab_count_;
+  ELF::Word mips_local_got_count_;
+  ELF::Word mips_gotsym_;
+#endif
+
+  uint8_t* android_relocations_;
+  size_t android_relocations_size_;
+
+  bool has_text_relocations_;
+  bool has_symbolic_;
+};
+
+}  // namespace crazy
+
+#endif  // CRAZY_LINKER_ELF_RELOCATIONS_H