| 1 | // compressed_output.h -- compressed output sections for gold -*- C++ -*- |
| 2 | |
| 3 | // Copyright (C) 2007-2019 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) |