gold/testsuite/plugin_test.c

   1 /* test_plugin.c -- simple linker plugin test
   2
   3    Copyright 2008 Free Software Foundation, Inc.
   4    Written by Cary Coutant <ccoutant@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 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include "plugin-api.h"
  27
  28 struct claimed_file
  29 {
  30   const char* name;
  31   void* handle;
  32   int nsyms;
  33   struct ld_plugin_symbol* syms;
  34   struct claimed_file* next;
  35 };
  36
  37 static struct claimed_file* first_claimed_file = NULL;
  38 static struct claimed_file* last_claimed_file = NULL;
  39
  40 static ld_plugin_register_claim_file register_claim_file_hook = NULL;
  41 static ld_plugin_register_all_symbols_read register_all_symbols_read_hook = NULL;
  42 static ld_plugin_register_cleanup register_cleanup_hook = NULL;
  43 static ld_plugin_add_symbols add_symbols = NULL;
  44 static ld_plugin_get_symbols get_symbols = NULL;
  45 static ld_plugin_add_input_file add_input_file = NULL;
  46 static ld_plugin_message message = NULL;
  47
  48 #define MAXOPTS 10
  49
  50 static const char *opts[MAXOPTS];
  51 static int nopts = 0;
  52
  53 enum ld_plugin_status onload(struct ld_plugin_tv *tv);
  54 enum ld_plugin_status claim_file_hook(const struct ld_plugin_input_file *file,
  55                                       int *claimed);
  56 enum ld_plugin_status all_symbols_read_hook(void);
  57 enum ld_plugin_status cleanup_hook(void);
  58
  59 enum ld_plugin_status
  60 onload(struct ld_plugin_tv *tv)
  61 {
  62   struct ld_plugin_tv *entry;
  63   int api_version = 0;
  64   int gold_version = 0;
  65   int i;
  66
  67   for (entry = tv; entry->tv_tag != LDPT_NULL; ++entry)
  68     {
  69       switch (entry->tv_tag)
  70         {
  71         case LDPT_API_VERSION:
  72           api_version = entry->tv_u.tv_val;
  73           break;
  74         case LDPT_GOLD_VERSION:
  75           gold_version = entry->tv_u.tv_val;
  76           break;
  77         case LDPT_LINKER_OUTPUT:
  78           break;
  79         case LDPT_OPTION:
  80           if (nopts < MAXOPTS)
  81             opts[nopts++] = entry->tv_u.tv_string;
  82           break;
  83         case LDPT_REGISTER_CLAIM_FILE_HOOK:
  84           register_claim_file_hook = entry->tv_u.tv_register_claim_file;
  85           break;
  86         case LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK:
  87           register_all_symbols_read_hook =
  88             entry->tv_u.tv_register_all_symbols_read;
  89           break;
  90         case LDPT_REGISTER_CLEANUP_HOOK:
  91           register_cleanup_hook = entry->tv_u.tv_register_cleanup;
  92           break;
  93         case LDPT_ADD_SYMBOLS:
  94           add_symbols = entry->tv_u.tv_add_symbols;
  95           break;
  96         case LDPT_GET_SYMBOLS:
  97           get_symbols = entry->tv_u.tv_get_symbols;
  98           break;
  99         case LDPT_ADD_INPUT_FILE:
 100           add_input_file = entry->tv_u.tv_add_input_file;
 101           break;
 102         case LDPT_MESSAGE:
 103           message = entry->tv_u.tv_message;
 104           break;
 105         default:
 106           break;
 107         }
 108     }
 109
 110   if (message == NULL)
 111     {
 112       fprintf(stderr, "tv_message interface missing\n");
 113       return LDPS_ERR;
 114     }
 115
 116   if (register_claim_file_hook == NULL)
 117     {
 118       fprintf(stderr, "tv_register_claim_file_hook interface missing\n");
 119       return LDPS_ERR;
 120     }
 121
 122   if (register_all_symbols_read_hook == NULL)
 123     {
 124       fprintf(stderr, "tv_register_all_symbols_read_hook interface missing\n");
 125       return LDPS_ERR;
 126     }
 127
 128   if (register_cleanup_hook == NULL)
 129     {
 130       fprintf(stderr, "tv_register_cleanup_hook interface missing\n");
 131       return LDPS_ERR;
 132     }
 133
 134   (*message)(LDPL_INFO, "API version:   %d", api_version);
 135   (*message)(LDPL_INFO, "gold version:  %d", gold_version);
 136
 137   for (i = 0; i < nopts; ++i)
 138     (*message)(LDPL_INFO, "option: %s", opts[i]);
 139
 140   if ((*register_claim_file_hook)(claim_file_hook) != LDPS_OK)
 141     {
 142       (*message)(LDPL_ERROR, "error registering claim file hook");
 143       return LDPS_ERR;
 144     }
 145
 146   if ((*register_all_symbols_read_hook)(all_symbols_read_hook) != LDPS_OK)
 147     {
 148       (*message)(LDPL_ERROR, "error registering all symbols read hook");
 149       return LDPS_ERR;
 150     }
 151
 152   if ((*register_cleanup_hook)(cleanup_hook) != LDPS_OK)
 153     {
 154       (*message)(LDPL_ERROR, "error registering cleanup hook");
 155       return LDPS_ERR;
 156     }
 157
 158   return LDPS_OK;
 159 }
 160
 161 enum ld_plugin_status
 162 claim_file_hook (const struct ld_plugin_input_file* file, int* claimed)
 163 {
 164   int len;
 165   char buf[160];
 166   struct claimed_file* claimed_file;
 167   struct ld_plugin_symbol* syms;
 168   int nsyms = 0;
 169   int maxsyms = 0;
 170   FILE* irfile;
 171   char *p;
 172   char *pbind;
 173   char *pvis;
 174   char *psect;
 175   int weak;
 176   int def;
 177   int vis;
 178   int size;
 179   char* name;
 180   int is_comdat;
 181   int i;
 182
 183   (*message)(LDPL_INFO,
 184              "%s: claim file hook called (offset = %ld, size = %ld)",
 185              file->name, (long)file->offset, (long)file->filesize);
 186
 187   /* Look for the beginning of output from readelf -s.  */
 188   irfile = fdopen(file->fd, "r");
 189   (void)fseek(irfile, file->offset, SEEK_SET);
 190   len = fread(buf, 1, 13, irfile);
 191   if (len < 13 || strncmp(buf, "\nSymbol table", 13) != 0)
 192     return LDPS_OK;
 193
 194   /* Skip the two header lines.  */
 195   (void) fgets(buf, sizeof(buf), irfile);
 196   (void) fgets(buf, sizeof(buf), irfile);
 197
 198   if (add_symbols == NULL)
 199     {
 200       fprintf(stderr, "tv_add_symbols interface missing\n");
 201       return LDPS_ERR;
 202     }
 203
 204   /* Parse the output from readelf. The columns are:
 205      Index Value Size Type Binding Visibility Section Name.  */
 206   syms = (struct ld_plugin_symbol*)malloc(sizeof(struct ld_plugin_symbol) * 8);
 207   if (syms == NULL)
 208     return LDPS_ERR;
 209   maxsyms = 8;
 210   while (fgets(buf, sizeof(buf), irfile) != NULL)
 211     {
 212       p = buf;
 213       p += strspn(p, " ");
 214
 215       /* Index field.  */
 216       p += strcspn(p, " ");
 217       p += strspn(p, " ");
 218
 219       /* Value field.  */
 220       p += strcspn(p, " ");
 221       p += strspn(p, " ");
 222
 223       /* Size field.  */
 224       size = atoi(p);
 225       p += strcspn(p, " ");
 226       p += strspn(p, " ");
 227
 228       /* Type field.  */
 229       p += strcspn(p, " ");
 230       p += strspn(p, " ");
 231
 232       /* Binding field.  */
 233       pbind = p;
 234       p += strcspn(p, " ");
 235       p += strspn(p, " ");
 236
 237       /* Visibility field.  */
 238       pvis = p;
 239       p += strcspn(p, " ");
 240       p += strspn(p, " ");
 241
 242       /* Section field.  */
 243       psect = p;
 244       p += strcspn(p, " ");
 245       p += strspn(p, " ");
 246
 247       /* Name field.  */
 248       /* FIXME:  Look for version.  */
 249       len = strlen(p);
 250       if (p[len-1] == '\n')
 251         p[--len] = '\0';
 252       name = malloc(len + 1);
 253       strncpy(name, p, len + 1);
 254
 255       /* Ignore local symbols.  */
 256       if (strncmp(pbind, "LOCAL", 5) == 0)
 257         continue;
 258
 259       weak = strncmp(pbind, "WEAK", 4) == 0;
 260       if (strncmp(psect, "UND", 3) == 0)
 261         def = weak ? LDPK_WEAKUNDEF : LDPK_UNDEF;
 262       else if (strncmp(psect, "COM", 3) == 0)
 263         def = LDPK_COMMON;
 264       else
 265         def = weak ? LDPK_WEAKDEF : LDPK_DEF;
 266
 267       if (strncmp(pvis, "INTERNAL", 8) == 0)
 268         vis = LDPV_INTERNAL;
 269       else if (strncmp(pvis, "HIDDEN", 6) == 0)
 270         vis = LDPV_HIDDEN;
 271       else if (strncmp(pvis, "PROTECTED", 9) == 0)
 272         vis = LDPV_PROTECTED;
 273       else
 274         vis = LDPV_DEFAULT;
 275
 276       /* If the symbol is listed in the options list, special-case
 277          it as a comdat symbol.  */
 278       is_comdat = 0;
 279       for (i = 0; i < nopts; ++i)
 280         {
 281           if (name != NULL && strcmp(name, opts[i]) == 0)
 282             {
 283               is_comdat = 1;
 284               break;
 285             }
 286         }
 287
 288       if (nsyms >= maxsyms)
 289         {
 290           syms = (struct ld_plugin_symbol*)
 291             realloc(syms, sizeof(struct ld_plugin_symbol) * maxsyms * 2);
 292           if (syms == NULL)
 293             return LDPS_ERR;
 294           maxsyms *= 2;
 295         }
 296
 297       syms[nsyms].name = name;
 298       syms[nsyms].version = NULL;
 299       syms[nsyms].def = def;
 300       syms[nsyms].visibility = vis;
 301       syms[nsyms].size = size;
 302       syms[nsyms].comdat_key = is_comdat ? name : NULL;
 303       syms[nsyms].resolution = LDPR_UNKNOWN;
 304       ++nsyms;
 305     }
 306
 307   claimed_file = (struct claimed_file*) malloc(sizeof(struct claimed_file));
 308   if (claimed_file == NULL)
 309     return LDPS_ERR;
 310
 311   claimed_file->name = file->name;
 312   claimed_file->handle = file->handle;
 313   claimed_file->nsyms = nsyms;
 314   claimed_file->syms = syms;
 315   claimed_file->next = NULL;
 316   if (last_claimed_file == NULL)
 317     first_claimed_file = claimed_file;
 318   else
 319     last_claimed_file->next = claimed_file;
 320   last_claimed_file = claimed_file;
 321
 322   (*message)(LDPL_INFO, "%s: claiming file, adding %d symbols",
 323              file->name, nsyms);
 324
 325   if (nsyms > 0)
 326     (*add_symbols)(file->handle, nsyms, syms);
 327
 328   *claimed = 1;
 329   return LDPS_OK;
 330 }
 331
 332 enum ld_plugin_status
 333 all_symbols_read_hook(void)
 334 {
 335   int i;
 336   const char* res;
 337   struct claimed_file* claimed_file;
 338   char buf[160];
 339   char *p;
 340
 341   (*message)(LDPL_INFO, "all symbols read hook called");
 342
 343   if (get_symbols == NULL)
 344     {
 345       fprintf(stderr, "tv_get_symbols interface missing\n");
 346       return LDPS_ERR;
 347     }
 348
 349   for (claimed_file = first_claimed_file;
 350        claimed_file != NULL;
 351        claimed_file = claimed_file->next)
 352     {
 353       (*get_symbols)(claimed_file->handle, claimed_file->nsyms,
 354                      claimed_file->syms);
 355       for (i = 0; i < claimed_file->nsyms; ++i)
 356         {
 357           switch (claimed_file->syms[i].resolution)
 358             {
 359             case LDPR_UNKNOWN:
 360               res = "UNKNOWN";
 361               break;
 362             case LDPR_UNDEF:
 363               res = "UNDEF";
 364               break;
 365             case LDPR_PREVAILING_DEF:
 366               res = "PREVAILING_DEF_REG";
 367               break;
 368             case LDPR_PREVAILING_DEF_IRONLY:
 369               res = "PREVAILING_DEF_IRONLY";
 370               break;
 371             case LDPR_PREEMPTED_REG:
 372               res = "PREEMPTED_REG";
 373               break;
 374             case LDPR_PREEMPTED_IR:
 375               res = "PREEMPTED_IR";
 376               break;
 377             case LDPR_RESOLVED_IR:
 378               res = "RESOLVED_IR";
 379               break;
 380             case LDPR_RESOLVED_EXEC:
 381               res = "RESOLVED_EXEC";
 382               break;
 383             case LDPR_RESOLVED_DYN:
 384               res = "RESOLVED_DYN";
 385               break;
 386             default:
 387               res = "?";
 388               break;
 389             }
 390           (*message)(LDPL_INFO, "%s: %s: %s", claimed_file->name,
 391                      claimed_file->syms[i].name, res);
 392         }
 393     }
 394
 395   if (add_input_file == NULL)
 396     {
 397       fprintf(stderr, "tv_add_input_file interface missing\n");
 398       return LDPS_ERR;
 399     }
 400
 401   for (claimed_file = first_claimed_file;
 402        claimed_file != NULL;
 403        claimed_file = claimed_file->next)
 404     {
 405       if (claimed_file->nsyms == 0)
 406         continue;
 407       if (strlen(claimed_file->name) >= sizeof(buf))
 408         {
 409           (*message)(LDPL_FATAL, "%s: filename too long", claimed_file->name);
 410           return LDPS_ERR;
 411         }
 412       strcpy(buf, claimed_file->name);
 413       p = strrchr(buf, '.');
 414       if (p == NULL || strcmp(p, ".syms") != 0)
 415         {
 416           (*message)(LDPL_FATAL, "%s: filename must have '.syms' suffix",
 417                      claimed_file->name);
 418           return LDPS_ERR;
 419         }
 420       p[1] = 'o';
 421       p[2] = '\0';
 422       (*add_input_file)(buf);
 423     }
 424
 425   return LDPS_OK;
 426 }
 427
 428 enum ld_plugin_status
 429 cleanup_hook(void)
 430 {
 431   (*message)(LDPL_INFO, "cleanup hook called");
 432   return LDPS_OK;
 433 }