diff options
Diffstat (limited to 'gold/object.cc')
| -rw-r--r-- | gold/object.cc | 196 |
1 files changed, 121 insertions, 75 deletions
diff --git a/gold/object.cc b/gold/object.cc index 677c731..1bfd969 100644 --- a/gold/object.cc +++ b/gold/object.cc @@ -19,6 +19,22 @@ namespace gold // Class Object. +// Set the target based on fields in the ELF file header. + +void +Object::set_target(int machine, int size, bool big_endian, int osabi, + int abiversion) +{ + Target* target = select_target(machine, size, big_endian, osabi, abiversion); + if (target == NULL) + { + fprintf(stderr, _("%s: %s: unsupported ELF machine number %d\n"), + program_name, this->name().c_str(), machine); + gold_exit(false); + } + this->target_ = target; +} + // Report an error for the elfcpp::Elf_file interface. void @@ -45,6 +61,58 @@ Object::section_contents(unsigned int shndx, off_t* plen) return this->get_view(loc.file_offset, loc.data_size); } +// Read the section data into SD. This is code common to Sized_relobj +// and Sized_dynobj, so we put it into Object. + +template<int size, bool big_endian> +void +Object::read_section_data(elfcpp::Elf_file<size, big_endian, Object>* elf_file, + Read_symbols_data* sd) +{ + const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size; + + // Read the section headers. + const off_t shoff = elf_file->shoff(); + const unsigned int shnum = this->shnum(); + sd->section_headers = this->get_lasting_view(shoff, shnum * shdr_size); + + // Read the section names. + const unsigned char* pshdrs = sd->section_headers->data(); + const unsigned char* pshdrnames = pshdrs + elf_file->shstrndx() * shdr_size; + typename elfcpp::Shdr<size, big_endian> shdrnames(pshdrnames); + + if (shdrnames.get_sh_type() != elfcpp::SHT_STRTAB) + { + fprintf(stderr, + _("%s: %s: section name section has wrong type: %u\n"), + program_name, this->name().c_str(), + static_cast<unsigned int>(shdrnames.get_sh_type())); + gold_exit(false); + } + + sd->section_names_size = shdrnames.get_sh_size(); + sd->section_names = this->get_lasting_view(shdrnames.get_sh_offset(), + sd->section_names_size); +} + +// If NAME is the name of a special .gnu.warning section, arrange for +// the warning to be issued. SHNDX is the section index. Return +// whether it is a warning section. + +bool +Object::handle_gnu_warning_section(const char* name, unsigned int shndx, + Symbol_table* symtab) +{ + const char warn_prefix[] = ".gnu.warning."; + const int warn_prefix_len = sizeof warn_prefix - 1; + if (strncmp(name, warn_prefix, warn_prefix_len) == 0) + { + symtab->add_warning(name + warn_prefix_len, this, shndx); + return true; + } + return false; +} + // Class Sized_relobj. template<int size, bool big_endian> @@ -55,8 +123,7 @@ Sized_relobj<size, big_endian>::Sized_relobj( const elfcpp::Ehdr<size, big_endian>& ehdr) : Relobj(name, input_file, offset), elf_file_(this, ehdr), - section_headers_(NULL), - symtab_shndx_(0), + symtab_shndx_(-1U), local_symbol_count_(0), output_local_symbol_count_(0), symbols_(NULL), @@ -78,43 +145,41 @@ void Sized_relobj<size, big_endian>::setup( const elfcpp::Ehdr<size, big_endian>& ehdr) { - int machine = ehdr.get_e_machine(); - Target* target = select_target(machine, size, big_endian, - ehdr.get_e_ident()[elfcpp::EI_OSABI], - ehdr.get_e_ident()[elfcpp::EI_ABIVERSION]); - if (target == NULL) - { - fprintf(stderr, _("%s: %s: unsupported ELF machine number %d\n"), - program_name, this->name().c_str(), machine); - gold_exit(false); - } - this->set_target(target); + this->set_target(ehdr.get_e_machine(), size, big_endian, + ehdr.get_e_ident()[elfcpp::EI_OSABI], + ehdr.get_e_ident()[elfcpp::EI_ABIVERSION]); - unsigned int shnum = this->elf_file_.shnum(); + const unsigned int shnum = this->elf_file_.shnum(); this->set_shnum(shnum); - if (shnum == 0) - return; - - // We store the section headers in a File_view until do_read_symbols. - off_t shoff = this->elf_file_.shoff(); - this->section_headers_ = this->get_lasting_view(shoff, - shnum * This::shdr_size); +} - // Find the SHT_SYMTAB section. The ELF standard says that maybe in - // the future there can be more than one SHT_SYMTAB section. Until - // somebody figures out how that could work, we assume there is only - // one. - const unsigned char* p = this->section_headers_->data(); +// Find the SHT_SYMTAB section, given the section headers. The ELF +// standard says that maybe in the future there can be more than one +// SHT_SYMTAB section. Until somebody figures out how that could +// work, we assume there is only one. - // Skip the first section, which is always empty. - p += This::shdr_size; - for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size) +template<int size, bool big_endian> +void +Sized_relobj<size, big_endian>::find_symtab(const unsigned char* pshdrs) +{ + const unsigned int shnum = this->shnum(); + this->symtab_shndx_ = 0; + if (shnum > 0) { - typename This::Shdr shdr(p); - if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB) + // Look through the sections in reverse order, since gas tends + // to put the symbol table at the end. + const unsigned char* p = pshdrs + shnum * This::shdr_size; + unsigned int i = shnum; + while (i > 0) { - this->symtab_shndx_ = i; - break; + --i; + p -= This::shdr_size; + typename This::Shdr shdr(p); + if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB) + { + this->symtab_shndx_ = i; + break; + } } } } @@ -125,19 +190,11 @@ template<int size, bool big_endian> void Sized_relobj<size, big_endian>::do_read_symbols(Read_symbols_data* sd) { - // Transfer our view of the section headers to SD. - sd->section_headers = this->section_headers_; - this->section_headers_ = NULL; + this->read_section_data(&this->elf_file_, sd); - // Read the section names. - const unsigned char* pshdrs = sd->section_headers->data(); - const unsigned char* pshdrnames = (pshdrs - + (this->elf_file_.shstrndx() - * This::shdr_size)); - typename This::Shdr shdrnames(pshdrnames); - sd->section_names_size = shdrnames.get_sh_size(); - sd->section_names = this->get_lasting_view(shdrnames.get_sh_offset(), - sd->section_names_size); + const unsigned char* const pshdrs = sd->section_headers->data(); + + this->find_symtab(pshdrs); if (this->symtab_shndx_ == 0) { @@ -166,15 +223,14 @@ Sized_relobj<size, big_endian>::do_read_symbols(Read_symbols_data* sd) File_view* fvsymtab = this->get_lasting_view(extoff, extsize); // Read the section header for the symbol names. - unsigned int shnum = this->shnum(); - unsigned int strtab_shnum = symtabshdr.get_sh_link(); - if (strtab_shnum == 0 || strtab_shnum >= shnum) + unsigned int strtab_shndx = symtabshdr.get_sh_link(); + if (strtab_shndx >= this->shnum()) { fprintf(stderr, _("%s: %s: invalid symbol table name index: %u\n"), - program_name, this->name().c_str(), strtab_shnum); + program_name, this->name().c_str(), strtab_shndx); gold_exit(false); } - typename This::Shdr strtabshdr(pshdrs + strtab_shnum * This::shdr_size); + typename This::Shdr strtabshdr(pshdrs + strtab_shndx * This::shdr_size); if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB) { fprintf(stderr, @@ -336,7 +392,7 @@ Sized_relobj<size, big_endian>::do_layout(const General_options& options, Layout* layout, Read_symbols_data* sd) { - unsigned int shnum = this->shnum(); + const unsigned int shnum = this->shnum(); if (shnum == 0) return; @@ -353,9 +409,6 @@ Sized_relobj<size, big_endian>::do_layout(const General_options& options, // Keep track of which sections to omit. std::vector<bool> omit(shnum, false); - const char warn_prefix[] = ".gnu.warning."; - const int warn_prefix_len = sizeof warn_prefix - 1; - // Skip the first, dummy, section. pshdrs += This::shdr_size; for (unsigned int i = 1; i < shnum; ++i, pshdrs += This::shdr_size) @@ -373,9 +426,8 @@ Sized_relobj<size, big_endian>::do_layout(const General_options& options, const char* name = pnames + shdr.get_sh_name(); - if (strncmp(name, warn_prefix, warn_prefix_len) == 0) + if (this->handle_gnu_warning_section(name, i, symtab)) { - symtab->add_warning(name + warn_prefix_len, this, i); if (!options.is_relocatable()) omit[i] = true; } @@ -442,10 +494,8 @@ Sized_relobj<size, big_endian>::do_add_symbols(Symbol_table* symtab, const char* sym_names = reinterpret_cast<const char*>(sd->symbol_names->data()); - symtab->add_from_object<size, big_endian>(this, sd->symbols->data(), - symcount, sym_names, - sd->symbol_names_size, - this->symbols_); + symtab->add_from_relobj(this, sd->symbols->data(), symcount, sym_names, + sd->symbol_names_size, this->symbols_); delete sd->symbols; sd->symbols = NULL; @@ -464,6 +514,7 @@ off_t Sized_relobj<size, big_endian>::do_finalize_local_symbols(off_t off, Stringpool* pool) { + assert(this->symtab_shndx_ != -1U); if (this->symtab_shndx_ == 0) { // This object has no symbols. Weird but legal. @@ -577,6 +628,7 @@ void Sized_relobj<size, big_endian>::write_local_symbols(Output_file* of, const Stringpool* sympool) { + assert(this->symtab_shndx_ != -1U); if (this->symtab_shndx_ == 0) { // This object has no symbols. Weird but legal. @@ -711,13 +763,6 @@ make_elf_sized_object(const std::string& name, Input_file* input_file, off_t offset, const elfcpp::Ehdr<size, big_endian>& ehdr) { int et = ehdr.get_e_type(); - if (et != elfcpp::ET_REL && et != elfcpp::ET_DYN) - { - fprintf(stderr, "%s: %s: unsupported ELF type %d\n", - program_name, name.c_str(), static_cast<int>(et)); - gold_exit(false); - } - if (et == elfcpp::ET_REL) { Sized_relobj<size, big_endian>* obj = @@ -725,17 +770,18 @@ make_elf_sized_object(const std::string& name, Input_file* input_file, obj->setup(ehdr); return obj; } + else if (et == elfcpp::ET_DYN) + { + Sized_dynobj<size, big_endian>* obj = + new Sized_dynobj<size, big_endian>(name, input_file, offset, ehdr); + obj->setup(ehdr); + return obj; + } else { - // elfcpp::ET_DYN - fprintf(stderr, _("%s: %s: dynamic objects are not yet supported\n"), - program_name, name.c_str()); + fprintf(stderr, _("%s: %s: unsupported ELF file type %d\n"), + program_name, name.c_str(), et); gold_exit(false); -// Sized_dynobj<size, big_endian>* obj = -// new Sized_dynobj<size, big_endian>(this->input_.name(), input_file, -// offset, ehdr); -// obj->setup(ehdr); -// return obj; } } |