gold/gold.h

   1 // gold.h -- general definitions for gold   -*- C++ -*-
   2
   3 // Copyright (C) 2006-2023 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 #ifndef GOLD_GOLD_H
  24 #define GOLD_GOLD_H
  25
  26 #include "config.h"
  27 #include "ansidecl.h"
  28
  29 #include <cstddef>
  30 #include <cstdlib>
  31 #include <cstring>
  32 #include <stdint.h>
  33 #include <sys/types.h>
  34
  35 #include "system.h"
  36
  37 namespace gold
  38 {
  39
  40 // General declarations.
  41
  42 class General_options;
  43 class Command_line;
  44 class Dirsearch;
  45 class Input_objects;
  46 class Mapfile;
  47 class Symbol;
  48 class Symbol_table;
  49 class Layout;
  50 class Task;
  51 class Workqueue;
  52 class Output_file;
  53 template<int size, bool big_endian>
  54 struct Relocate_info;
  55
  56 // Exit status codes.
  57
  58 enum Exit_status
  59 {
  60   GOLD_OK = EXIT_SUCCESS,
  61   GOLD_ERR = EXIT_FAILURE,
  62   GOLD_FALLBACK = EXIT_FAILURE + 1
  63 };
  64
  65 // Some basic types.  For these we use lower case initial letters.
  66
  67 // For an offset in an input or output file, use off_t.  Note that
  68 // this will often be a 64-bit type even for a 32-bit build.
  69
  70 // The size of a section if we are going to look at the contents.
  71 typedef size_t section_size_type;
  72
  73 // An offset within a section when we are looking at the contents.
  74 typedef ptrdiff_t section_offset_type;
  75
  76 // The name of the program as used in error messages.
  77 extern const char* program_name;
  78
  79 // This function is called to exit the program.  Status is true to
  80 // exit success (0) and false to exit failure (1).
  81 extern void
  82 gold_exit(Exit_status status) ATTRIBUTE_NORETURN;
  83
  84 // This function is called to emit an error message and then
  85 // immediately exit with failure.
  86 extern void
  87 gold_fatal(const char* format, ...) ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF_1;
  88
  89 // This function is called to issue an error.  This will cause gold to
  90 // eventually exit with failure.
  91 extern void
  92 gold_error(const char* msg, ...) ATTRIBUTE_PRINTF_1;
  93
  94 // This function is called to issue a warning.
  95 extern void
  96 gold_warning(const char* msg, ...) ATTRIBUTE_PRINTF_1;
  97
  98 // This function is called to print an informational message.
  99 extern void
 100 gold_info(const char* msg, ...) ATTRIBUTE_PRINTF_1;
 101
 102 // This function is called to print a trace message.
 103 extern void
 104 gold_trace(const char* msg, ...) ATTRIBUTE_PRINTF_1;
 105
 106 // This function is called to emit an error message and then
 107 // immediately exit with fallback status (e.g., when
 108 // --incremental-update fails and the link needs to be restarted
 109 // with --incremental-full).
 110 extern void
 111 gold_fallback(const char* format, ...) ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF_1;
 112
 113 // Work around a bug in gcc 4.3.0.  http://gcc.gnu.org/PR35546 .  This
 114 // can probably be removed after the bug has been fixed for a while.
 115 #ifdef HAVE_TEMPLATE_ATTRIBUTES
 116 #define TEMPLATE_ATTRIBUTE_PRINTF_4 ATTRIBUTE_PRINTF_4
 117 #else
 118 #define TEMPLATE_ATTRIBUTE_PRINTF_4
 119 #endif
 120
 121 // This function is called to issue an error at the location of a
 122 // reloc.
 123 template<int size, bool big_endian>
 124 extern void
 125 gold_error_at_location(const Relocate_info<size, big_endian>*,
 126                        size_t, off_t, const char* format, ...)
 127   TEMPLATE_ATTRIBUTE_PRINTF_4;
 128
 129 // This function is called to issue a warning at the location of a
 130 // reloc.
 131 template<int size, bool big_endian>
 132 extern void
 133 gold_warning_at_location(const Relocate_info<size, big_endian>*,
 134                          size_t, off_t, const char* format, ...)
 135   TEMPLATE_ATTRIBUTE_PRINTF_4;
 136
 137 // This function is called to report an undefined symbol without
 138 // a relocation (e.g., referenced by a dynamic object).  SYM is
 139 // the undefined symbol.  The file name associated with the SYM
 140 // is used to print a location for the undefined symbol.
 141 extern void
 142 gold_undefined_symbol(const Symbol*);
 143
 144 // This function is called to report an undefined symbol resulting
 145 // from a relocation.  SYM is the undefined symbol.  RELINFO is the
 146 // general relocation info.  RELNUM is the number of the reloc,
 147 // and RELOFFSET is the reloc's offset.
 148 template<int size, bool big_endian>
 149 extern void
 150 gold_undefined_symbol_at_location(const Symbol*,
 151                                   const Relocate_info<size, big_endian>*,
 152                                   size_t, off_t);
 153
 154 // This is function is called in some cases if we run out of memory.
 155 extern void
 156 gold_nomem() ATTRIBUTE_NORETURN;
 157
 158 // In versions of gcc before 4.3, using __FUNCTION__ in a template
 159 // function can cause gcc to get confused about whether or not the
 160 // function can return.  See http://gcc.gnu.org/PR30988.  Use a macro
 161 // to avoid the problem.  This can be removed when we no longer need
 162 // to care about gcc versions before 4.3.
 163 #if defined(__GNUC__) && GCC_VERSION < 4003
 164 #define FUNCTION_NAME static_cast<const char*>(__FUNCTION__)
 165 #else
 166 #define FUNCTION_NAME __FUNCTION__
 167 #endif
 168
 169 // This macro and function are used in cases which can not arise if
 170 // the code is written correctly.
 171
 172 #define gold_unreachable() \
 173   (gold::do_gold_unreachable(__FILE__, __LINE__, FUNCTION_NAME))
 174
 175 extern void do_gold_unreachable(const char*, int, const char*)
 176   ATTRIBUTE_NORETURN;
 177
 178 // Assertion check.
 179
 180 #define gold_assert(expr) ((void)(!(expr) ? gold_unreachable(), 0 : 0))
 181
 182 // Print version information.
 183 extern void
 184 print_version(bool print_short);
 185
 186 // Get the version string.
 187 extern const char*
 188 get_version_string();
 189
 190 // Convert numeric types without unnoticed loss of precision.
 191 template<typename To, typename From>
 192 inline To
 193 convert_types(const From from)
 194 {
 195   To to = from;
 196   gold_assert(static_cast<From>(to) == from);
 197   return to;
 198 }
 199
 200 // A common case of convert_types<>: convert to section_size_type.
 201 template<typename From>
 202 inline section_size_type
 203 convert_to_section_size_type(const From from)
 204 { return convert_types<section_size_type, From>(from); }
 205
 206 // Queue up the first set of tasks.
 207 extern void
 208 queue_initial_tasks(const General_options&,
 209                     Dirsearch&,
 210                     const Command_line&,
 211                     Workqueue*,
 212                     Input_objects*,
 213                     Symbol_table*,
 214                     Layout*,
 215                     Mapfile*);
 216
 217 // Queue up the set of tasks to be done before
 218 // the middle set of tasks.  Only used when garbage
 219 // collection is to be done.
 220 extern void
 221 queue_middle_gc_tasks(const General_options&,
 222                       const Task*,
 223                       const Input_objects*,
 224                       Symbol_table*,
 225                       Layout*,
 226                       Workqueue*,
 227                       Mapfile*);
 228
 229 // Queue up the middle set of tasks.
 230 extern void
 231 queue_middle_tasks(const General_options&,
 232                    const Task*,
 233                    const Input_objects*,
 234                    Symbol_table*,
 235                    Layout*,
 236                    Workqueue*,
 237                    Mapfile*);
 238
 239 // Queue up the final set of tasks.
 240 extern void
 241 queue_final_tasks(const General_options&,
 242                   const Input_objects*,
 243                   const Symbol_table*,
 244                   Layout*,
 245                   Workqueue*,
 246                   Output_file* of);
 247
 248 inline bool
 249 is_prefix_of(const char* prefix, const char* str)
 250 {
 251   return strncmp(prefix, str, strlen(prefix)) == 0;
 252 }
 253
 254 const char* const cident_section_start_prefix = "__start_";
 255 const char* const cident_section_stop_prefix = "__stop_";
 256
 257 // Returns true if the name is a valid C identifier
 258 inline bool
 259 is_cident(const char* name)
 260 {
 261   return (name[strspn(name,
 262                       ("0123456789"
 263                        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
 264                        "abcdefghijklmnopqrstuvwxyz"
 265                        "_"))]
 266           == '\0');
 267 }
 268
 269 // We sometimes need to hash strings.  Ideally we should use std::tr1::hash or
 270 // __gnu_cxx::hash on some systems but there is no guarantee that either
 271 // one is available.  For portability, we define simple string hash functions.
 272
 273 template<typename Char_type>
 274 inline size_t
 275 string_hash(const Char_type* s, size_t length)
 276 {
 277   // This is the hash function used by the dynamic linker for
 278   // DT_GNU_HASH entries.  I compared this to a Fowler/Noll/Vo hash
 279   // for a C++ program with 385,775 global symbols.  This hash
 280   // function was very slightly worse.  However, it is much faster to
 281   // compute.  Overall wall clock time was a win.
 282   const unsigned char* p = reinterpret_cast<const unsigned char*>(s);
 283   size_t h = 5381;
 284   for (size_t i = 0; i < length * sizeof(Char_type); ++i)
 285     h = h * 33 + *p++;
 286   return h;
 287 }
 288
 289 // Same as above except we expect the string to be zero terminated.
 290
 291 template<typename Char_type>
 292 inline size_t
 293 string_hash(const Char_type* s)
 294 {
 295   const unsigned char* p = reinterpret_cast<const unsigned char*>(s);
 296   size_t h = 5381;
 297   for (size_t i = 0; s[i] != 0; ++i)
 298     {
 299       for (size_t j = 0; j < sizeof(Char_type); j++)
 300         h = h * 33 + *p++;
 301     }
 302
 303   return h;
 304 }
 305
 306 // Return whether STRING contains a wildcard character.  This is used
 307 // to speed up matching.
 308
 309 inline bool
 310 is_wildcard_string(const char* s)
 311 {
 312   return strpbrk(s, "?*[") != NULL;
 313 }
 314
 315 } // End namespace gold.
 316
 317 #endif // !defined(GOLD_GOLD_H)