include/plugin-api.h

   1 /* plugin-api.h -- External linker plugin API.  */
   2
   3 /* Copyright 2008 Free Software Foundation, Inc.
   4    Written by Cary Coutant <ccoutant@google.com>.
   5
   6    This file is part of binutils.
   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 /* This file defines the interface for writing a linker plugin, which is
  24    described at < http://gcc.gnu.org/wiki/whopr/driver >.  */
  25
  26 #ifndef PLUGIN_API_H
  27 #define PLUGIN_API_H
  28
  29 #include <stdint.h>
  30 #include <sys/types.h>
  31
  32 #ifdef __cplusplus
  33 extern "C"
  34 {
  35 #endif
  36
  37 /* Status code returned by most API routines.  */
  38
  39 enum ld_plugin_status
  40 {
  41   LDPS_OK = 0,
  42   LDPS_NO_SYMS,         /* Attempt to get symbols that haven't been added. */
  43   LDPS_ERR
  44   /* Additional Error codes TBD.  */
  45 };
  46
  47 /* The version of the API specification.  */
  48
  49 enum ld_plugin_api_version
  50 {
  51   LD_PLUGIN_API_VERSION = 1
  52 };
  53
  54 /* The type of output file being generated by the linker.  */
  55
  56 enum ld_plugin_output_file_type
  57 {
  58   LDPO_REL,
  59   LDPO_EXEC,
  60   LDPO_DYN
  61 };
  62
  63 /* An input file managed by the plugin library.  */
  64
  65 struct ld_plugin_input_file
  66 {
  67   const char *name;
  68   int fd;
  69   off_t offset;
  70   off_t filesize;
  71   void *handle;
  72 };
  73
  74 /* A symbol belonging to an input file managed by the plugin library.  */
  75
  76 struct ld_plugin_symbol
  77 {
  78   char *name;
  79   char *version;
  80   int def;
  81   int visibility;
  82   uint64_t size;
  83   char *comdat_key;
  84   int resolution;
  85 };
  86
  87 /* Whether the symbol is a definition, reference, or common, weak or not.  */
  88
  89 enum ld_plugin_symbol_kind
  90 {
  91   LDPK_DEF,
  92   LDPK_WEAKDEF,
  93   LDPK_UNDEF,
  94   LDPK_WEAKUNDEF,
  95   LDPK_COMMON
  96 };
  97
  98 /* The visibility of the symbol.  */
  99
 100 enum ld_plugin_symbol_visibility
 101 {
 102   LDPV_DEFAULT,
 103   LDPV_PROTECTED,
 104   LDPV_INTERNAL,
 105   LDPV_HIDDEN
 106 };
 107
 108 /* How a symbol is resolved.  */
 109
 110 enum ld_plugin_symbol_resolution
 111 {
 112   LDPR_UNKNOWN = 0,
 113   LDPR_UNDEF,
 114   LDPR_PREVAILING_DEF,
 115   LDPR_PREVAILING_DEF_IRONLY,
 116   LDPR_PREEMPTED_REG,
 117   LDPR_PREEMPTED_IR,
 118   LDPR_RESOLVED_IR,
 119   LDPR_RESOLVED_EXEC,
 120   LDPR_RESOLVED_DYN
 121 };
 122
 123 /* The plugin library's "claim file" handler.  */
 124
 125 typedef
 126 enum ld_plugin_status
 127 (*ld_plugin_claim_file_handler) (
 128   const struct ld_plugin_input_file *file, int *claimed);
 129
 130 /* The plugin library's "all symbols read" handler.  */
 131
 132 typedef
 133 enum ld_plugin_status
 134 (*ld_plugin_all_symbols_read_handler) (void);
 135
 136 /* The plugin library's cleanup handler.  */
 137
 138 typedef
 139 enum ld_plugin_status
 140 (*ld_plugin_cleanup_handler) (void);
 141
 142 /* The linker's interface for registering the "claim file" handler.  */
 143
 144 typedef
 145 enum ld_plugin_status
 146 (*ld_plugin_register_claim_file) (ld_plugin_claim_file_handler handler);
 147
 148 /* The linker's interface for registering the "all symbols read" handler.  */
 149
 150 typedef
 151 enum ld_plugin_status
 152 (*ld_plugin_register_all_symbols_read) (
 153   ld_plugin_all_symbols_read_handler handler);
 154
 155 /* The linker's interface for registering the cleanup handler.  */
 156
 157 typedef
 158 enum ld_plugin_status
 159 (*ld_plugin_register_cleanup) (ld_plugin_cleanup_handler handler);
 160
 161 /* The linker's interface for adding symbols from a claimed input file.  */
 162
 163 typedef
 164 enum ld_plugin_status
 165 (*ld_plugin_add_symbols) (void *handle, int nsyms,
 166                           const struct ld_plugin_symbol *syms);
 167
 168 /* The linker's interface for retrieving symbol resolution information.  */
 169
 170 typedef
 171 enum ld_plugin_status
 172 (*ld_plugin_get_symbols) (const void *handle, int nsyms,
 173                           struct ld_plugin_symbol *syms);
 174
 175 /* The linker's interface for adding a compiled input file.  */
 176
 177 typedef
 178 enum ld_plugin_status
 179 (*ld_plugin_add_input_file) (char *pathname);
 180
 181 /* The linker's interface for issuing a warning or error message.  */
 182
 183 typedef
 184 enum ld_plugin_status
 185 (*ld_plugin_message) (int level, char *format, ...);
 186
 187 enum ld_plugin_level
 188 {
 189   LDPL_INFO,
 190   LDPL_WARNING,
 191   LDPL_ERROR,
 192   LDPL_FATAL
 193 };
 194
 195 /* Values for the tv_tag field of the transfer vector.  */
 196
 197 enum ld_plugin_tag
 198 {
 199   LDPT_NULL = 0,
 200   LDPT_API_VERSION,
 201   LDPT_GOLD_VERSION,
 202   LDPT_LINKER_OUTPUT,
 203   LDPT_OPTION,
 204   LDPT_REGISTER_CLAIM_FILE_HOOK,
 205   LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK,
 206   LDPT_REGISTER_CLEANUP_HOOK,
 207   LDPT_ADD_SYMBOLS,
 208   LDPT_GET_SYMBOLS,
 209   LDPT_ADD_INPUT_FILE,
 210   LDPT_MESSAGE
 211 };
 212
 213 /* The plugin transfer vector.  */
 214
 215 struct ld_plugin_tv
 216 {
 217   enum ld_plugin_tag tv_tag;
 218   union
 219   {
 220     int tv_val;
 221     const char *tv_string;
 222     ld_plugin_register_claim_file tv_register_claim_file;
 223     ld_plugin_register_all_symbols_read tv_register_all_symbols_read;
 224     ld_plugin_register_cleanup tv_register_cleanup;
 225     ld_plugin_add_symbols tv_add_symbols;
 226     ld_plugin_get_symbols tv_get_symbols;
 227     ld_plugin_add_input_file tv_add_input_file;
 228     ld_plugin_message tv_message;
 229   } tv_u;
 230 };
 231
 232 /* The plugin library's "onload" entry point.  */
 233
 234 typedef
 235 enum ld_plugin_status
 236 (*ld_plugin_onload) (struct ld_plugin_tv *tv);
 237
 238 #ifdef __cplusplus
 239 }
 240 #endif
 241
 242 #endif /* !defined(PLUGIN_API_H) */