1 // compressed_output.h -- compressed output sections for gold -*- C++ -*- 2 3 // Copyright (C) 2007-2016 Free Software Foundation, Inc. 4 // Written by Ian Lance Taylor <iant@google.com>. 5 6 // This file is part of gold. 7 8 // This program is free software; you can redistribute it and/or modify 9 // it under the terms of the GNU General Public License as published by 10 // the Free Software Foundation; either version 3 of the License, or 11 // (at your option) any later version. 12 13 // This program is distributed in the hope that it will be useful, 14 // but WITHOUT ANY WARRANTY; without even the implied warranty of 15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 // GNU General Public License for more details. 17 18 // You should have received a copy of the GNU General Public License 19 // along with this program; if not, write to the Free Software 20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 21 // MA 02110-1301, USA. 22 23 // We support compressing .debug_* sections on output. (And, 24 // potentially one day, other sections.) This is a form of 25 // relaxation. This file adds support for merging and emitting the 26 // compressed sections. 27 28 #ifndef GOLD_COMPRESSED_OUTPUT_H 29 #define GOLD_COMPRESSED_OUTPUT_H 30 31 #include <string> 32 33 #include "output.h" 34 35 namespace gold 36 { 37 38 class General_options; 39 40 // Read the compression header of a compressed debug section and return 41 // the uncompressed size. 42 43 extern uint64_t 44 get_uncompressed_size(const unsigned char*, section_size_type); 45 46 // Decompress a compressed debug section directly into the output file. 47 48 extern bool 49 decompress_input_section(const unsigned char*, unsigned long, unsigned char*, 50 unsigned long, int, bool, elfcpp::Elf_Xword); 51 52 // This is used for a section whose data should be compressed. It is 53 // a regular Output_section which computes its contents into a buffer 54 // and then postprocesses it. 55 56 class Output_compressed_section : public Output_section 57 { 58 public: 59 Output_compressed_section(const General_options* options, 60 const char* name, elfcpp::Elf_Word flags, 61 elfcpp::Elf_Xword type) 62 : Output_section(name, flags, type), 63 options_(options) 64 { this->set_requires_postprocessing(); } 65 66 protected: 67 // Set the final data size. 68 void 69 set_final_data_size(); 70 71 // Write out the compressed contents. 72 void 73 do_write(Output_file*); 74 75 private: 76 // The options--this includes the compression type. 77 const General_options* options_; 78 // The compressed data. 79 unsigned char* data_; 80 // The new section name if we do compress. 81 std::string new_section_name_; 82 }; 83 84 } // End namespace gold. 85 86 #endif // !defined(GOLD_COMPRESSED_OUTPUT_H) 87