xref: /dflybsd-src/contrib/binutils-2.34/gold/compressed_output.h (revision b52ef7118d1621abed722c5bbbd542210290ecef)
1*fae548d3Szrj // compressed_output.h -- compressed output sections for gold  -*- C++ -*-
2*fae548d3Szrj 
3*fae548d3Szrj // Copyright (C) 2007-2020 Free Software Foundation, Inc.
4*fae548d3Szrj // Written by Ian Lance Taylor <iant@google.com>.
5*fae548d3Szrj 
6*fae548d3Szrj // This file is part of gold.
7*fae548d3Szrj 
8*fae548d3Szrj // This program is free software; you can redistribute it and/or modify
9*fae548d3Szrj // it under the terms of the GNU General Public License as published by
10*fae548d3Szrj // the Free Software Foundation; either version 3 of the License, or
11*fae548d3Szrj // (at your option) any later version.
12*fae548d3Szrj 
13*fae548d3Szrj // This program is distributed in the hope that it will be useful,
14*fae548d3Szrj // but WITHOUT ANY WARRANTY; without even the implied warranty of
15*fae548d3Szrj // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16*fae548d3Szrj // GNU General Public License for more details.
17*fae548d3Szrj 
18*fae548d3Szrj // You should have received a copy of the GNU General Public License
19*fae548d3Szrj // along with this program; if not, write to the Free Software
20*fae548d3Szrj // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21*fae548d3Szrj // MA 02110-1301, USA.
22*fae548d3Szrj 
23*fae548d3Szrj // We support compressing .debug_* sections on output.  (And,
24*fae548d3Szrj // potentially one day, other sections.)  This is a form of
25*fae548d3Szrj // relaxation.  This file adds support for merging and emitting the
26*fae548d3Szrj // compressed sections.
27*fae548d3Szrj 
28*fae548d3Szrj #ifndef GOLD_COMPRESSED_OUTPUT_H
29*fae548d3Szrj #define GOLD_COMPRESSED_OUTPUT_H
30*fae548d3Szrj 
31*fae548d3Szrj #include <string>
32*fae548d3Szrj 
33*fae548d3Szrj #include "output.h"
34*fae548d3Szrj 
35*fae548d3Szrj namespace gold
36*fae548d3Szrj {
37*fae548d3Szrj 
38*fae548d3Szrj class General_options;
39*fae548d3Szrj 
40*fae548d3Szrj // Read the compression header of a compressed debug section and return
41*fae548d3Szrj // the uncompressed size.
42*fae548d3Szrj 
43*fae548d3Szrj extern uint64_t
44*fae548d3Szrj get_uncompressed_size(const unsigned char*, section_size_type);
45*fae548d3Szrj 
46*fae548d3Szrj // Decompress a compressed debug section directly into the output file.
47*fae548d3Szrj 
48*fae548d3Szrj extern bool
49*fae548d3Szrj decompress_input_section(const unsigned char*, unsigned long, unsigned char*,
50*fae548d3Szrj 			 unsigned long, int, bool, elfcpp::Elf_Xword);
51*fae548d3Szrj 
52*fae548d3Szrj // This is used for a section whose data should be compressed.  It is
53*fae548d3Szrj // a regular Output_section which computes its contents into a buffer
54*fae548d3Szrj // and then postprocesses it.
55*fae548d3Szrj 
56*fae548d3Szrj class Output_compressed_section : public Output_section
57*fae548d3Szrj {
58*fae548d3Szrj  public:
Output_compressed_section(const General_options * options,const char * name,elfcpp::Elf_Word flags,elfcpp::Elf_Xword type)59*fae548d3Szrj   Output_compressed_section(const General_options* options,
60*fae548d3Szrj 			    const char* name, elfcpp::Elf_Word flags,
61*fae548d3Szrj 			    elfcpp::Elf_Xword type)
62*fae548d3Szrj     : Output_section(name, flags, type),
63*fae548d3Szrj       options_(options)
64*fae548d3Szrj   { this->set_requires_postprocessing(); }
65*fae548d3Szrj 
66*fae548d3Szrj  protected:
67*fae548d3Szrj   // Set the final data size.
68*fae548d3Szrj   void
69*fae548d3Szrj   set_final_data_size();
70*fae548d3Szrj 
71*fae548d3Szrj   // Write out the compressed contents.
72*fae548d3Szrj   void
73*fae548d3Szrj   do_write(Output_file*);
74*fae548d3Szrj 
75*fae548d3Szrj  private:
76*fae548d3Szrj   // The options--this includes the compression type.
77*fae548d3Szrj   const General_options* options_;
78*fae548d3Szrj   // The compressed data.
79*fae548d3Szrj   unsigned char* data_;
80*fae548d3Szrj   // The new section name if we do compress.
81*fae548d3Szrj   std::string new_section_name_;
82*fae548d3Szrj };
83*fae548d3Szrj 
84*fae548d3Szrj } // End namespace gold.
85*fae548d3Szrj 
86*fae548d3Szrj #endif // !defined(GOLD_COMPRESSED_OUTPUT_H)
87