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// dynobj.h -- dynamic object support for gold -*- C++ -*-
#ifndef GOLD_DYNOBJ_H
#define GOLD_DYNOBJ_H
#include <vector>
#include "object.h"
namespace gold
{
// A dynamic object (ET_DYN). This is an abstract base class itself.
// The implementations is the template class Sized_dynobj.
class Dynobj : public Object
{
public:
Dynobj(const std::string& name, Input_file* input_file, off_t offset = 0)
: Object(name, input_file, true, offset), soname_()
{ }
// Return the name to use in a DT_NEEDED entry for this object.
const char*
soname() const;
// Create a standard ELF hash table, setting *PPHASH and *PHASHLEN.
// DYNSYMS is the global dynamic symbols. LOCAL_DYNSYM_COUNT is the
// number of local dynamic symbols, which is the index of the first
// dynamic gobal symbol.
static void
create_elf_hash_table(const Target*, const std::vector<Symbol*>& dynsyms,
unsigned int local_dynsym_count,
unsigned char** pphash,
unsigned int* phashlen);
// Create a GNU hash table, setting *PPHASH and *PHASHLEN. DYNSYMS
// is the global dynamic symbols. LOCAL_DYNSYM_COUNT is the number
// of local dynamic symbols, which is the index of the first dynamic
// gobal symbol.
static void
create_gnu_hash_table(const Target*, const std::vector<Symbol*>& dynsyms,
unsigned int local_dynsym_count,
unsigned char** pphash, unsigned int* phashlen);
protected:
// Set the DT_SONAME string.
void
set_soname_string(const char* s)
{ this->soname_.assign(s); }
private:
// Compute the ELF hash code for a string.
static uint32_t
elf_hash(const char*);
// Compute the GNU hash code for a string.
static uint32_t
gnu_hash(const char*);
// Compute the number of hash buckets to use.
static unsigned int
compute_bucket_count(const std::vector<uint32_t>& hashcodes,
bool for_gnu_hash_table);
// Sized version of create_elf_hash_table.
template<bool big_endian>
static void
sized_create_elf_hash_table(const std::vector<uint32_t>& bucket,
const std::vector<uint32_t>& chain,
unsigned char* phash,
unsigned int hashlen);
// Sized version of create_gnu_hash_table.
template<int size, bool big_endian>
static void
sized_create_gnu_hash_table(const std::vector<Symbol*>& hashed_dynsyms,
const std::vector<uint32_t>& dynsym_hashvals,
unsigned int unhashed_dynsym_count,
unsigned char** pphash,
unsigned int* phashlen);
// The DT_SONAME name, if any.
std::string soname_;
};
// A dynamic object, size and endian specific version.
template<int size, bool big_endian>
class Sized_dynobj : public Dynobj
{
public:
Sized_dynobj(const std::string& name, Input_file* input_file, off_t offset,
const typename elfcpp::Ehdr<size, big_endian>&);
// Set up the object file based on the ELF header.
void
setup(const typename elfcpp::Ehdr<size, big_endian>&);
// Read the symbols.
void
do_read_symbols(Read_symbols_data*);
// Lay out the input sections.
void
do_layout(const General_options&, Symbol_table*, Layout*,
Read_symbols_data*);
// Add the symbols to the symbol table.
void
do_add_symbols(Symbol_table*, Read_symbols_data*);
// Get the name of a section.
std::string
do_section_name(unsigned int shndx)
{ return this->elf_file_.section_name(shndx); }
// Return a view of the contents of a section. Set *PLEN to the
// size.
Object::Location
do_section_contents(unsigned int shndx)
{ return this->elf_file_.section_contents(shndx); }
// Return section flags.
uint64_t
do_section_flags(unsigned int shndx)
{ return this->elf_file_.section_flags(shndx); }
private:
// For convenience.
typedef Sized_dynobj<size, big_endian> This;
static const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
static const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
static const int dyn_size = elfcpp::Elf_sizes<size>::dyn_size;
typedef elfcpp::Shdr<size, big_endian> Shdr;
typedef elfcpp::Dyn<size, big_endian> Dyn;
// Find the dynamic symbol table and the version sections, given the
// section headers.
void
find_dynsym_sections(const unsigned char* pshdrs,
unsigned int* pdynshm_shndx,
unsigned int* pversym_shndx,
unsigned int* pverdef_shndx,
unsigned int* pverneed_shndx,
unsigned int* pdynamic_shndx);
// Read the dynamic symbol section SHNDX.
void
read_dynsym_section(const unsigned char* pshdrs, unsigned int shndx,
elfcpp::SHT type, unsigned int link,
File_view** view, off_t* view_size,
unsigned int* view_info);
// Set the SONAME from the SHT_DYNAMIC section at DYNAMIC_SHNDX.
// The STRTAB parameters may have the relevant string table.
void
set_soname(const unsigned char* pshdrs, unsigned int dynamic_shndx,
unsigned int strtab_shndx, const unsigned char* strtabu,
off_t strtab_size);
// Mapping from version number to version name.
typedef std::vector<const char*> Version_map;
// Create the version map.
void
make_version_map(Read_symbols_data* sd, Version_map*) const;
// Add an entry to the version map.
void
set_version_map(Version_map*, unsigned int ndx, const char* name) const;
// General access to the ELF file.
elfcpp::Elf_file<size, big_endian, Object> elf_file_;
};
} // End namespace gold.
#endif // !defined(GOLD_DYNOBJ_H)
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