| // Copyright 2018 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_GNU_HASH_TABLE_H |
| #define CRAZY_LINKER_GNU_HASH_TABLE_H |
| |
| #include <stddef.h> |
| #include "elf_traits.h" |
| |
| namespace crazy { |
| |
| // Models the hash table used to map symbol names to symbol entries using |
| // the GNU format. This one is smaller and faster than the standard ELF one. |
| class GnuHashTable { |
| public: |
| // Initialize instance. |dt_gnu_hash| should be the address that the |
| // DT_GNU_HASH entry points to in the input ELF dynamic section. Call |
| // IsValid() to determine whether the table was well-formed. |
| void Init(uintptr_t dt_gnu_hash); |
| |
| // Returns true iff the content of the table is valid. |
| bool IsValid() const; |
| |
| // Return the index of the first dynamic symbol within the ELF symbol table. |
| size_t dyn_symbols_offset() const { return sym_offset_; }; |
| |
| // Number of dynamic symbols in the ELF symbol table. |
| size_t dyn_symbols_count() const { return sym_count_; } |
| |
| // Lookup |symbol_name| in the table. |symbol_table| should point to the |
| // ELF symbol table, and |string_table| to the start of its string table. |
| // Returns nullptr on failure. |
| const ELF::Sym* LookupByName(const char* symbol_name, |
| const ELF::Sym* symbol_table, |
| const char* string_table) const; |
| |
| private: |
| uint32_t num_buckets_ = 0; |
| uint32_t sym_offset_ = 0; |
| uint32_t sym_count_ = 0; |
| uint32_t bloom_word_mask_ = 0; |
| uint32_t bloom_shift_ = 0; |
| const ELF::Addr* bloom_filter_ = nullptr; |
| const uint32_t* buckets_ = nullptr; |
| const uint32_t* chain_ = nullptr; |
| }; |
| |
| } // namespace crazy |
| |
| #endif // CRAZY_LINKER_GNU_HASH_TABLE_H |