text: // gold.h -- general definitions for gold   -*- C++ -*-
  
  // Copyright (C) 2006-2014 Free Software Foundation, Inc.
  // Written by Ian Lance Taylor <iant@google.com>.
  
  // This file is part of gold.
  
  // This program is free software; you can redistribute it and/or modify
  // it under the terms of the GNU General Public License as published by
  // the Free Software Foundation; either version 3 of the License, or
  // (at your option) any later version.
  
  // This program is distributed in the hope that it will be useful,
  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  // GNU General Public License for more details.
  
  // You should have received a copy of the GNU General Public License
  // along with this program; if not, write to the Free Software
  // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  // MA 02110-1301, USA.
  
  #ifndef GOLD_GOLD_H
  #define GOLD_GOLD_H
  
  #include "config.h"
  #include "ansidecl.h"
  
  #include <cstddef>
  #include <cstdlib>
  #include <cstring>
  #include <stdint.h>
  #include <sys/types.h>
  
  #include "system.h"
  
  namespace gold
  {
  
  // General declarations.
  
  class General_options;
  class Command_line;
  class Dirsearch;
  class Input_objects;
  class Mapfile;
  class Symbol;
  class Symbol_table;
  class Layout;
  class Task;
  class Workqueue;
  class Output_file;
  template<int size, bool big_endian>
  struct Relocate_info;
  
  // Exit status codes.
  
  enum Exit_status
  {
    GOLD_OK = EXIT_SUCCESS,
    GOLD_ERR = EXIT_FAILURE,
    GOLD_FALLBACK = EXIT_FAILURE + 1
  };
  
  // Some basic types.  For these we use lower case initial letters.
  
  // For an offset in an input or output file, use off_t.  Note that
  // this will often be a 64-bit type even for a 32-bit build.
  
  // The size of a section if we are going to look at the contents.
  typedef size_t section_size_type;
  
  // An offset within a section when we are looking at the contents.
  typedef ptrdiff_t section_offset_type;
  
  // The name of the program as used in error messages.
  extern const char* program_name;
  
  // This function is called to exit the program.  Status is true to
  // exit success (0) and false to exit failure (1).
  extern void
  gold_exit(Exit_status status) ATTRIBUTE_NORETURN;
  
  // This function is called to emit an error message and then
  // immediately exit with failure.
  extern void
  gold_fatal(const char* format, ...) ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF_1;
  
  // This function is called to issue an error.  This will cause gold to
  // eventually exit with failure.
  extern void
  gold_error(const char* msg, ...) ATTRIBUTE_PRINTF_1;
  
  // This function is called to issue a warning.
  extern void
  gold_warning(const char* msg, ...) ATTRIBUTE_PRINTF_1;
  
  // This function is called to print an informational message.
  extern void
  gold_info(const char* msg, ...) ATTRIBUTE_PRINTF_1;
  
  // This function is called to emit an error message and then
  // immediately exit with fallback status (e.g., when
  // --incremental-update fails and the link needs to be restarted
  // with --incremental-full).
  extern void
  gold_fallback(const char* format, ...) ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF_1;
  
  // Work around a bug in gcc 4.3.0.  http://gcc.gnu.org/PR35546 .  This
  // can probably be removed after the bug has been fixed for a while.
  #ifdef HAVE_TEMPLATE_ATTRIBUTES
  #define TEMPLATE_ATTRIBUTE_PRINTF_4 ATTRIBUTE_PRINTF_4
  #else
  #define TEMPLATE_ATTRIBUTE_PRINTF_4
  #endif
  
  // This function is called to issue an error at the location of a
  // reloc.
  template<int size, bool big_endian>
  extern void
  gold_error_at_location(const Relocate_info<size, big_endian>*,
  		       size_t, off_t, const char* format, ...)
    TEMPLATE_ATTRIBUTE_PRINTF_4;
  
  // This function is called to issue a warning at the location of a
  // reloc.
  template<int size, bool big_endian>
  extern void
  gold_warning_at_location(const Relocate_info<size, big_endian>*,
  			 size_t, off_t, const char* format, ...)
    TEMPLATE_ATTRIBUTE_PRINTF_4;
  
  // This function is called to report an undefined symbol without
  // a relocation (e.g., referenced by a dynamic object).  SYM is
  // the undefined symbol.  The file name associated with the SYM
  // is used to print a location for the undefined symbol.
  extern void
  gold_undefined_symbol(const Symbol*);
  
  // This function is called to report an undefined symbol resulting
  // from a relocation.  SYM is the undefined symbol.  RELINFO is the
  // general relocation info.  RELNUM is the number of the reloc,
  // and RELOFFSET is the reloc's offset.
  template<int size, bool big_endian>
  extern void
  gold_undefined_symbol_at_location(const Symbol*,
  		                  const Relocate_info<size, big_endian>*,
  		                  size_t, off_t);
  
  // This is function is called in some cases if we run out of memory.
  extern void
  gold_nomem() ATTRIBUTE_NORETURN;
  
  // In versions of gcc before 4.3, using __FUNCTION__ in a template
  // function can cause gcc to get confused about whether or not the
  // function can return.  See http://gcc.gnu.org/PR30988.  Use a macro
  // to avoid the problem.  This can be removed when we no longer need
  // to care about gcc versions before 4.3.
  #if defined(__GNUC__) && GCC_VERSION < 4003
  #define FUNCTION_NAME static_cast<const char*>(__FUNCTION__)
  #else 
  #define FUNCTION_NAME __FUNCTION__
  #endif
  
  // This macro and function are used in cases which can not arise if
  // the code is written correctly.
  
  #define gold_unreachable() \
    (gold::do_gold_unreachable(__FILE__, __LINE__, FUNCTION_NAME))
  
  extern void do_gold_unreachable(const char*, int, const char*)
    ATTRIBUTE_NORETURN;
  
  // Assertion check.
  
  #define gold_assert(expr) ((void)(!(expr) ? gold_unreachable(), 0 : 0))
  
  // Print version information.
  extern void
  print_version(bool print_short);
  
  // Get the version string.
  extern const char*
  get_version_string();
  
  // Convert numeric types without unnoticed loss of precision.
  template<typename To, typename From>
  inline To
  convert_types(const From from)
  {
    To to = from;
    gold_assert(static_cast<From>(to) == from);
    return to;
  }
  
  // A common case of convert_types<>: convert to section_size_type.
  template<typename From>
  inline section_size_type
  convert_to_section_size_type(const From from)
  { return convert_types<section_size_type, From>(from); }
  
  // Queue up the first set of tasks.
  extern void
  queue_initial_tasks(const General_options&,
  		    Dirsearch&,
  		    const Command_line&,
  		    Workqueue*,
  		    Input_objects*,
  		    Symbol_table*,
  		    Layout*,
  		    Mapfile*);
  
  // Queue up the set of tasks to be done before
  // the middle set of tasks.  Only used when garbage
  // collection is to be done.
  extern void
  queue_middle_gc_tasks(const General_options&,
                        const Task*,
                        const Input_objects*,
                        Symbol_table*,
                        Layout*,
                        Workqueue*,
                        Mapfile*);
  
  // Queue up the middle set of tasks.
  extern void
  queue_middle_tasks(const General_options&,
  		   const Task*,
  		   const Input_objects*,
  		   Symbol_table*,
  		   Layout*,
  		   Workqueue*,
  		   Mapfile*);
  
  // Queue up the final set of tasks.
  extern void
  queue_final_tasks(const General_options&,
  		  const Input_objects*,
  		  const Symbol_table*,
  		  Layout*,
  		  Workqueue*,
  		  Output_file* of);
  
  inline bool
  is_prefix_of(const char* prefix, const char* str)
  {
    return strncmp(prefix, str, strlen(prefix)) == 0;
  }
  
  const char* const cident_section_start_prefix = "__start_";
  const char* const cident_section_stop_prefix = "__stop_";
  
  // Returns true if the name is a valid C identifier
  inline bool
  is_cident(const char* name)
  {
    return (name[strspn(name,
  	 	      ("0123456789"
  		       "ABCDEFGHIJKLMNOPWRSTUVWXYZ"
  		       "abcdefghijklmnopqrstuvwxyz"
  		       "_"))]
  	  == '\0');
  }
  
  // We sometimes need to hash strings.  Ideally we should use std::tr1::hash or
  // __gnu_cxx::hash on some systems but there is no guarantee that either
  // one is available.  For portability, we define simple string hash functions.
  
  template<typename Char_type>
  inline size_t
  string_hash(const Char_type* s, size_t length)
  {
    // This is the hash function used by the dynamic linker for
    // DT_GNU_HASH entries.  I compared this to a Fowler/Noll/Vo hash
    // for a C++ program with 385,775 global symbols.  This hash
    // function was very slightly worse.  However, it is much faster to
    // compute.  Overall wall clock time was a win.
    const unsigned char* p = reinterpret_cast<const unsigned char*>(s);
    size_t h = 5381;
    for (size_t i = 0; i < length * sizeof(Char_type); ++i)
      h = h * 33 + *p++;
    return h;
  }
  
  // Same as above except we expect the string to be zero terminated.
  
  template<typename Char_type>
  inline size_t
  string_hash(const Char_type* s)
  {
    const unsigned char* p = reinterpret_cast<const unsigned char*>(s);
    size_t h = 5381;
    for (size_t i = 0; s[i] != 0; ++i)
      {
        for (size_t j = 0; j < sizeof(Char_type); j++)
  	h = h * 33 + *p++;
      }
  
    return h;
  }
  
  // Return whether STRING contains a wildcard character.  This is used
  // to speed up matching.
  
  inline bool
  is_wildcard_string(const char* s)
  {
    return strpbrk(s, "?*[") != NULL;
  }
  
  } // End namespace gold.
  
  #endif // !defined(GOLD_GOLD_H)
  