ld/ldemul.h

   1 /* ld-emul.h - Linker emulation header file
   2    Copyright (C) 1991-2021 Free Software Foundation, Inc.
   3
   4    This file is part of the GNU Binutils.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  19    MA 02110-1301, USA.  */
  20
  21 #ifndef LDEMUL_H
  22 #define LDEMUL_H
  23
  24 /* Forward declaration for ldemul_add_options() and others.  */
  25 struct option;
  26
  27 extern void ldemul_hll
  28   (char *);
  29 extern void ldemul_syslib
  30   (char *);
  31 extern void ldemul_after_parse
  32   (void);
  33 extern void ldemul_before_parse
  34   (void);
  35 extern void ldemul_after_open
  36   (void);
  37 extern void ldemul_after_check_relocs
  38   (void);
  39 extern void ldemul_before_place_orphans
  40   (void);
  41 extern void ldemul_after_allocation
  42   (void);
  43 extern void ldemul_before_allocation
  44   (void);
  45 extern void ldemul_set_output_arch
  46   (void);
  47 extern char *ldemul_choose_target
  48   (int, char**);
  49 extern void ldemul_choose_mode
  50   (char *);
  51 extern void ldemul_list_emulations
  52   (FILE *);
  53 extern void ldemul_list_emulation_options
  54   (FILE *);
  55 extern char *ldemul_get_script
  56   (int *isfile);
  57 extern void ldemul_finish
  58   (void);
  59 extern void ldemul_set_symbols
  60   (void);
  61 extern void ldemul_create_output_section_statements
  62   (void);
  63 extern lang_output_section_statement_type *ldemul_place_orphan
  64   (asection *, const char *, int);
  65 extern bool ldemul_parse_args
  66   (int, char **);
  67 extern void ldemul_add_options
  68   (int, char **, int, struct option **, int, struct option **);
  69 extern bool ldemul_handle_option
  70   (int);
  71 extern bool ldemul_unrecognized_file
  72   (struct lang_input_statement_struct *);
  73 extern bool ldemul_recognized_file
  74   (struct lang_input_statement_struct *);
  75 extern bool ldemul_open_dynamic_archive
  76   (const char *, struct search_dirs *, struct lang_input_statement_struct *);
  77 extern char *ldemul_default_target
  78   (int, char**);
  79 extern void after_parse_default
  80   (void);
  81 extern void after_open_default
  82   (void);
  83 extern void after_check_relocs_default
  84   (void);
  85 extern void before_place_orphans_default
  86   (void);
  87 extern void after_allocation_default
  88   (void);
  89 extern void before_allocation_default
  90   (void);
  91 extern void finish_default
  92   (void);
  93 extern void finish_default
  94   (void);
  95 extern void set_output_arch_default
  96   (void);
  97 extern void syslib_default
  98   (char*);
  99 extern void hll_default
 100   (char*);
 101 extern int  ldemul_find_potential_libraries
 102   (char *, struct lang_input_statement_struct *);
 103 extern struct bfd_elf_version_expr *ldemul_new_vers_pattern
 104   (struct bfd_elf_version_expr *);
 105 extern void ldemul_extra_map_file_text
 106   (bfd *, struct bfd_link_info *, FILE *);
 107 /* Return 1 if we are emitting CTF early, and 0 if ldemul_examine_strtab_for_ctf
 108    will be called by the target.  */
 109 extern int ldemul_emit_ctf_early
 110   (void);
 111 /* Called from per-target code to examine the strtab and symtab.  */
 112 extern void ldemul_acquire_strings_for_ctf
 113   (struct ctf_dict *, struct elf_strtab_hash *);
 114 extern void ldemul_new_dynsym_for_ctf
 115   (struct ctf_dict *, int symidx, struct elf_internal_sym *);
 116
 117 extern bool ldemul_print_symbol
 118   (struct bfd_link_hash_entry *hash_entry, void *ptr);
 119
 120 typedef struct ld_emulation_xfer_struct {
 121   /* Run before parsing the command line and script file.
 122      Set the architecture, maybe other things.  */
 123   void   (*before_parse) (void);
 124
 125   /* Handle the SYSLIB (low level library) script command.  */
 126   void   (*syslib) (char *);
 127
 128   /* Handle the HLL (high level library) script command.  */
 129   void   (*hll) (char *);
 130
 131   /* Run after parsing the command line and script file.  */
 132   void   (*after_parse) (void);
 133
 134   /* Run after opening all input files, and loading the symbols.  */
 135   void   (*after_open) (void);
 136
 137   /* Run after checking relocations.  */
 138   void   (*after_check_relocs)  (void);
 139
 140   /* Run before placing orphans.  */
 141   void   (*before_place_orphans)  (void);
 142
 143   /* Run after allocating output sections.  */
 144   void   (*after_allocation)  (void);
 145
 146   /* Set the output architecture and machine if possible.  */
 147   void   (*set_output_arch) (void);
 148
 149   /* Decide which target name to use.  */
 150   char * (*choose_target) (int, char**);
 151
 152   /* Run before allocating output sections.  */
 153   void   (*before_allocation) (void);
 154
 155   /* Return the appropriate linker script.  */
 156   char * (*get_script) (int *isfile);
 157
 158   /* The name of this emulation.  */
 159   char *emulation_name;
 160
 161   /* The output format.  */
 162   char *target_name;
 163
 164   /* Run after assigning values from the script.  */
 165   void  (*finish) (void);
 166
 167   /* Create any output sections needed by the target.  */
 168   void  (*create_output_section_statements) (void);
 169
 170   /* Try to open a dynamic library.  ARCH is an architecture name, and
 171      is normally the empty string.  ENTRY is the lang_input_statement
 172      that should be opened.  */
 173   bool (*open_dynamic_archive)
 174     (const char *arch, struct search_dirs *,
 175      struct lang_input_statement_struct *entry);
 176
 177   /* Place an orphan section.  Return TRUE if it was placed, FALSE if
 178      the default action should be taken.  This field may be NULL, in
 179      which case the default action will always be taken.  */
 180   lang_output_section_statement_type *(*place_orphan)
 181     (asection *, const char *, int);
 182
 183   /* Run after assigning parsing with the args, but before
 184      reading the script.  Used to initialize symbols used in the script.  */
 185   void  (*set_symbols) (void);
 186
 187   /* Parse args which the base linker doesn't understand.
 188      Return TRUE if the arg needs no further processing.  */
 189   bool (*parse_args) (int, char **);
 190
 191   /* Hook to add options to parameters passed by the base linker to
 192      getopt_long and getopt_long_only calls.  */
 193   void (*add_options)
 194     (int, char **, int, struct option **, int, struct option **);
 195
 196   /* Companion to the above to handle an option.  Returns TRUE if it is
 197      one of our options.  */
 198   bool (*handle_option) (int);
 199
 200   /* Run to handle files which are not recognized as object files or
 201      archives.  Return TRUE if the file was handled.  */
 202   bool (*unrecognized_file)
 203     (struct lang_input_statement_struct *);
 204
 205   /* Run to list the command line options which parse_args handles.  */
 206   void (* list_options) (FILE *);
 207
 208   /* Run to specially handle files which *are* recognized as object
 209      files or archives.  Return TRUE if the file was handled.  */
 210   bool (*recognized_file)
 211     (struct lang_input_statement_struct *);
 212
 213   /* Called when looking for libraries in a directory specified
 214      via a linker command line option or linker script option.
 215      Files that match the pattern "lib*.a" have already been scanned.
 216      (For VMS files matching ":lib*.a" have also been scanned).  */
 217   int (* find_potential_libraries)
 218     (char *, struct lang_input_statement_struct *);
 219
 220   /* Called when adding a new version pattern.  PowerPC64-ELF uses
 221      this hook to add a pattern matching ".foo" for every "foo".  */
 222   struct bfd_elf_version_expr * (*new_vers_pattern)
 223     (struct bfd_elf_version_expr *);
 224
 225   /* Called when printing the map file, in case there are
 226      emulation-specific sections for it.  */
 227   void (*extra_map_file_text)
 228     (bfd *, struct bfd_link_info *, FILE *);
 229
 230   /* If this returns true, we emit CTF as early as possible: if false, we emit
 231      CTF once the strtab and symtab are laid out.  */
 232   int (*emit_ctf_early)
 233     (void);
 234
 235   /* Called to examine the string table late enough in linking that it is
 236      finally laid out.  If emit_ctf_early returns true, this is not called, and
 237      ldemul_maybe_emit_ctf emits CTF in 'early' mode: otherwise, it waits
 238      until 'late'. (Late mode needs explicit support at per-target link time to
 239      get called at all).  If set, called by ld when the examine_strtab
 240      bfd_link_callback is invoked by per-target code.  */
 241   void (*acquire_strings_for_ctf) (struct ctf_dict *, struct elf_strtab_hash *);
 242
 243   /* Called when a new symbol is added to the dynamic symbol table.  If
 244      emit_ctf_early returns true, this is not called, and ldemul_maybe_emit_ctf
 245      emits CTF in 'early' mode: otherwise, it waits until 'late'. (Late mode
 246      needs explicit support at per-target link time to get called at all).  If
 247      set, called by ld when the ctf_new_symbol bfd_link_callback is invoked by
 248      per-target code.  Called with a NULL symbol when no further symbols will be
 249      provided.  */
 250   void (*new_dynsym_for_ctf) (struct ctf_dict *, int, struct elf_internal_sym *);
 251
 252   /* Called when printing a symbol to the map file.   AIX uses this
 253      hook to flag gc'd symbols.  */
 254   bool (*print_symbol)
 255     (struct bfd_link_hash_entry *hash_entry, void *ptr);
 256
 257 } ld_emulation_xfer_type;
 258
 259 typedef enum {
 260   intel_ic960_ld_mode_enum,
 261   default_mode_enum,
 262   intel_gld960_ld_mode_enum
 263 } lang_emulation_mode_enum_type;
 264
 265 extern ld_emulation_xfer_type *ld_emulations[];
 266
 267 #endif