gold/testsuite/plugin_test.c

   1 /* test_plugin.c -- simple linker plugin test
   2
   3    Copyright (C) 2008-2015 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 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include "plugin-api.h"
  31
  32 struct claimed_file
  33 {
  34   const char* name;
  35   void* handle;
  36   int nsyms;
  37   struct ld_plugin_symbol* syms;
  38   struct claimed_file* next;
  39 };
  40
  41 struct sym_info
  42 {
  43   int size;
  44   char* type;
  45   char* bind;
  46   char* vis;
  47   char* sect;
  48   char* name;
  49 };
  50
  51 static struct claimed_file* first_claimed_file = NULL;
  52 static struct claimed_file* last_claimed_file = NULL;
  53
  54 static ld_plugin_register_claim_file register_claim_file_hook = NULL;
  55 static ld_plugin_register_all_symbols_read register_all_symbols_read_hook = NULL;
  56 static ld_plugin_register_cleanup register_cleanup_hook = NULL;
  57 static ld_plugin_add_symbols add_symbols = NULL;
  58 static ld_plugin_get_symbols get_symbols = NULL;
  59 static ld_plugin_get_symbols get_symbols_v2 = NULL;
  60 static ld_plugin_add_input_file add_input_file = NULL;
  61 static ld_plugin_message message = NULL;
  62 static ld_plugin_get_input_file get_input_file = NULL;
  63 static ld_plugin_release_input_file release_input_file = NULL;
  64 static ld_plugin_get_input_section_count get_input_section_count = NULL;
  65 static ld_plugin_get_input_section_type get_input_section_type = NULL;
  66 static ld_plugin_get_input_section_name get_input_section_name = NULL;
  67 static ld_plugin_get_input_section_contents get_input_section_contents = NULL;
  68 static ld_plugin_update_section_order update_section_order = NULL;
  69 static ld_plugin_allow_section_ordering allow_section_ordering = NULL;
  70
  71 #define MAXOPTS 10
  72
  73 static const char *opts[MAXOPTS];
  74 static int nopts = 0;
  75
  76 enum ld_plugin_status onload(struct ld_plugin_tv *tv);
  77 enum ld_plugin_status claim_file_hook(const struct ld_plugin_input_file *file,
  78                                       int *claimed);
  79 enum ld_plugin_status all_symbols_read_hook(void);
  80 enum ld_plugin_status cleanup_hook(void);
  81
  82 static void parse_readelf_line(char*, struct sym_info*);
  83
  84 enum ld_plugin_status
  85 onload(struct ld_plugin_tv *tv)
  86 {
  87   struct ld_plugin_tv *entry;
  88   int api_version = 0;
  89   int gold_version = 0;
  90   int i;
  91
  92   for (entry = tv; entry->tv_tag != LDPT_NULL; ++entry)
  93     {
  94       switch (entry->tv_tag)
  95         {
  96         case LDPT_API_VERSION:
  97           api_version = entry->tv_u.tv_val;
  98           break;
  99         case LDPT_GOLD_VERSION:
 100           gold_version = entry->tv_u.tv_val;
 101           break;
 102         case LDPT_LINKER_OUTPUT:
 103           break;
 104         case LDPT_OPTION:
 105           if (nopts < MAXOPTS)
 106             opts[nopts++] = entry->tv_u.tv_string;
 107           break;
 108         case LDPT_REGISTER_CLAIM_FILE_HOOK:
 109           register_claim_file_hook = entry->tv_u.tv_register_claim_file;
 110           break;
 111         case LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK:
 112           register_all_symbols_read_hook =
 113             entry->tv_u.tv_register_all_symbols_read;
 114           break;
 115         case LDPT_REGISTER_CLEANUP_HOOK:
 116           register_cleanup_hook = entry->tv_u.tv_register_cleanup;
 117           break;
 118         case LDPT_ADD_SYMBOLS:
 119           add_symbols = entry->tv_u.tv_add_symbols;
 120           break;
 121         case LDPT_GET_SYMBOLS:
 122           get_symbols = entry->tv_u.tv_get_symbols;
 123           break;
 124         case LDPT_GET_SYMBOLS_V2:
 125           get_symbols_v2 = entry->tv_u.tv_get_symbols;
 126           break;
 127         case LDPT_ADD_INPUT_FILE:
 128           add_input_file = entry->tv_u.tv_add_input_file;
 129           break;
 130         case LDPT_MESSAGE:
 131           message = entry->tv_u.tv_message;
 132           break;
 133         case LDPT_GET_INPUT_FILE:
 134           get_input_file = entry->tv_u.tv_get_input_file;
 135           break;
 136         case LDPT_RELEASE_INPUT_FILE:
 137           release_input_file = entry->tv_u.tv_release_input_file;
 138           break;
 139         case LDPT_GET_INPUT_SECTION_COUNT:
 140           get_input_section_count = *entry->tv_u.tv_get_input_section_count;
 141           break;
 142         case LDPT_GET_INPUT_SECTION_TYPE:
 143           get_input_section_type = *entry->tv_u.tv_get_input_section_type;
 144           break;
 145         case LDPT_GET_INPUT_SECTION_NAME:
 146           get_input_section_name = *entry->tv_u.tv_get_input_section_name;
 147           break;
 148         case LDPT_GET_INPUT_SECTION_CONTENTS:
 149           get_input_section_contents = *entry->tv_u.tv_get_input_section_contents;
 150           break;
 151         case LDPT_UPDATE_SECTION_ORDER:
 152           update_section_order = *entry->tv_u.tv_update_section_order;
 153           break;
 154         case LDPT_ALLOW_SECTION_ORDERING:
 155           allow_section_ordering = *entry->tv_u.tv_allow_section_ordering;
 156           break;
 157         default:
 158           break;
 159         }
 160     }
 161
 162   if (message == NULL)
 163     {
 164       fprintf(stderr, "tv_message interface missing\n");
 165       return LDPS_ERR;
 166     }
 167
 168   if (register_claim_file_hook == NULL)
 169     {
 170       fprintf(stderr, "tv_register_claim_file_hook interface missing\n");
 171       return LDPS_ERR;
 172     }
 173
 174   if (register_all_symbols_read_hook == NULL)
 175     {
 176       fprintf(stderr, "tv_register_all_symbols_read_hook interface missing\n");
 177       return LDPS_ERR;
 178     }
 179
 180   if (register_cleanup_hook == NULL)
 181     {
 182       fprintf(stderr, "tv_register_cleanup_hook interface missing\n");
 183       return LDPS_ERR;
 184     }
 185
 186   (*message)(LDPL_INFO, "API version:   %d", api_version);
 187   (*message)(LDPL_INFO, "gold version:  %d", gold_version);
 188
 189   for (i = 0; i < nopts; ++i)
 190     (*message)(LDPL_INFO, "option: %s", opts[i]);
 191
 192   if ((*register_claim_file_hook)(claim_file_hook) != LDPS_OK)
 193     {
 194       (*message)(LDPL_ERROR, "error registering claim file hook");
 195       return LDPS_ERR;
 196     }
 197
 198   if ((*register_all_symbols_read_hook)(all_symbols_read_hook) != LDPS_OK)
 199     {
 200       (*message)(LDPL_ERROR, "error registering all symbols read hook");
 201       return LDPS_ERR;
 202     }
 203
 204   if ((*register_cleanup_hook)(cleanup_hook) != LDPS_OK)
 205     {
 206       (*message)(LDPL_ERROR, "error registering cleanup hook");
 207       return LDPS_ERR;
 208     }
 209
 210   if (get_input_section_count == NULL)
 211     {
 212       fprintf(stderr, "tv_get_input_section_count interface missing\n");
 213       return LDPS_ERR;
 214     }
 215
 216   if (get_input_section_type == NULL)
 217     {
 218       fprintf(stderr, "tv_get_input_section_type interface missing\n");
 219       return LDPS_ERR;
 220     }
 221
 222   if (get_input_section_name == NULL)
 223     {
 224       fprintf(stderr, "tv_get_input_section_name interface missing\n");
 225       return LDPS_ERR;
 226     }
 227
 228   if (get_input_section_contents == NULL)
 229     {
 230       fprintf(stderr, "tv_get_input_section_contents interface missing\n");
 231       return LDPS_ERR;
 232     }
 233
 234   if (update_section_order == NULL)
 235     {
 236       fprintf(stderr, "tv_update_section_order interface missing\n");
 237       return LDPS_ERR;
 238     }
 239
 240   if (allow_section_ordering == NULL)
 241     {
 242       fprintf(stderr, "tv_allow_section_ordering interface missing\n");
 243       return LDPS_ERR;
 244     }
 245
 246   return LDPS_OK;
 247 }
 248
 249 enum ld_plugin_status
 250 claim_file_hook (const struct ld_plugin_input_file* file, int* claimed)
 251 {
 252   int len;
 253   off_t end_offset;
 254   char buf[160];
 255   struct claimed_file* claimed_file;
 256   struct ld_plugin_symbol* syms;
 257   int nsyms = 0;
 258   int maxsyms = 0;
 259   FILE* irfile;
 260   struct sym_info info;
 261   int weak;
 262   int def;
 263   int vis;
 264   int is_comdat;
 265   int i;
 266
 267   (*message)(LDPL_INFO,
 268              "%s: claim file hook called (offset = %ld, size = %ld)",
 269              file->name, (long)file->offset, (long)file->filesize);
 270
 271   /* Look for the beginning of output from readelf -s.  */
 272   irfile = fdopen(file->fd, "r");
 273   (void)fseek(irfile, file->offset, SEEK_SET);
 274   end_offset = file->offset + file->filesize;
 275   len = fread(buf, 1, 13, irfile);
 276   if (len < 13 || strncmp(buf, "\nSymbol table", 13) != 0)
 277     return LDPS_OK;
 278
 279   /* Skip the two header lines.  */
 280   (void) fgets(buf, sizeof(buf), irfile);
 281   (void) fgets(buf, sizeof(buf), irfile);
 282
 283   if (add_symbols == NULL)
 284     {
 285       fprintf(stderr, "tv_add_symbols interface missing\n");
 286       return LDPS_ERR;
 287     }
 288
 289   /* Parse the output from readelf. The columns are:
 290      Index Value Size Type Binding Visibility Section Name.  */
 291   syms = (struct ld_plugin_symbol*)malloc(sizeof(struct ld_plugin_symbol) * 8);
 292   if (syms == NULL)
 293     return LDPS_ERR;
 294   maxsyms = 8;
 295   while (ftell(irfile) < end_offset
 296          && fgets(buf, sizeof(buf), irfile) != NULL)
 297     {
 298       parse_readelf_line(buf, &info);
 299
 300       /* Ignore local symbols.  */
 301       if (strncmp(info.bind, "LOCAL", 5) == 0)
 302         continue;
 303
 304       weak = strncmp(info.bind, "WEAK", 4) == 0;
 305       if (strncmp(info.sect, "UND", 3) == 0)
 306         def = weak ? LDPK_WEAKUNDEF : LDPK_UNDEF;
 307       else if (strncmp(info.sect, "COM", 3) == 0)
 308         def = LDPK_COMMON;
 309       else
 310         def = weak ? LDPK_WEAKDEF : LDPK_DEF;
 311
 312       if (strncmp(info.vis, "INTERNAL", 8) == 0)
 313         vis = LDPV_INTERNAL;
 314       else if (strncmp(info.vis, "HIDDEN", 6) == 0)
 315         vis = LDPV_HIDDEN;
 316       else if (strncmp(info.vis, "PROTECTED", 9) == 0)
 317         vis = LDPV_PROTECTED;
 318       else
 319         vis = LDPV_DEFAULT;
 320
 321       /* If the symbol is listed in the options list, special-case
 322          it as a comdat symbol.  */
 323       is_comdat = 0;
 324       for (i = 0; i < nopts; ++i)
 325         {
 326           if (info.name != NULL && strcmp(info.name, opts[i]) == 0)
 327             {
 328               is_comdat = 1;
 329               break;
 330             }
 331         }
 332
 333       if (nsyms >= maxsyms)
 334         {
 335           syms = (struct ld_plugin_symbol*)
 336             realloc(syms, sizeof(struct ld_plugin_symbol) * maxsyms * 2);
 337           if (syms == NULL)
 338             return LDPS_ERR;
 339           maxsyms *= 2;
 340         }
 341
 342       if (info.name == NULL)
 343         syms[nsyms].name = NULL;
 344       else
 345         {
 346           len = strlen(info.name);
 347           syms[nsyms].name = malloc(len + 1);
 348           strncpy(syms[nsyms].name, info.name, len + 1);
 349         }
 350       syms[nsyms].version = NULL;
 351       syms[nsyms].def = def;
 352       syms[nsyms].visibility = vis;
 353       syms[nsyms].size = info.size;
 354       syms[nsyms].comdat_key = is_comdat ? syms[nsyms].name : NULL;
 355       syms[nsyms].resolution = LDPR_UNKNOWN;
 356       ++nsyms;
 357     }
 358
 359   claimed_file = (struct claimed_file*) malloc(sizeof(struct claimed_file));
 360   if (claimed_file == NULL)
 361     return LDPS_ERR;
 362
 363   claimed_file->name = file->name;
 364   claimed_file->handle = file->handle;
 365   claimed_file->nsyms = nsyms;
 366   claimed_file->syms = syms;
 367   claimed_file->next = NULL;
 368   if (last_claimed_file == NULL)
 369     first_claimed_file = claimed_file;
 370   else
 371     last_claimed_file->next = claimed_file;
 372   last_claimed_file = claimed_file;
 373
 374   (*message)(LDPL_INFO, "%s: claiming file, adding %d symbols",
 375              file->name, nsyms);
 376
 377   if (nsyms > 0)
 378     (*add_symbols)(file->handle, nsyms, syms);
 379
 380   *claimed = 1;
 381   return LDPS_OK;
 382 }
 383
 384 enum ld_plugin_status
 385 all_symbols_read_hook(void)
 386 {
 387   int i;
 388   const char* res;
 389   struct claimed_file* claimed_file;
 390   struct ld_plugin_input_file file;
 391   FILE* irfile;
 392   off_t end_offset;
 393   struct sym_info info;
 394   int len;
 395   char buf[160];
 396   char* p;
 397   const char* filename;
 398
 399   (*message)(LDPL_INFO, "all symbols read hook called");
 400
 401   if (get_symbols_v2 == NULL)
 402     {
 403       fprintf(stderr, "tv_get_symbols (v2) interface missing\n");
 404       return LDPS_ERR;
 405     }
 406
 407   for (claimed_file = first_claimed_file;
 408        claimed_file != NULL;
 409        claimed_file = claimed_file->next)
 410     {
 411       (*get_symbols_v2)(claimed_file->handle, claimed_file->nsyms,
 412                      claimed_file->syms);
 413
 414       for (i = 0; i < claimed_file->nsyms; ++i)
 415         {
 416           switch (claimed_file->syms[i].resolution)
 417             {
 418             case LDPR_UNKNOWN:
 419               res = "UNKNOWN";
 420               break;
 421             case LDPR_UNDEF:
 422               res = "UNDEF";
 423               break;
 424             case LDPR_PREVAILING_DEF:
 425               res = "PREVAILING_DEF_REG";
 426               break;
 427             case LDPR_PREVAILING_DEF_IRONLY:
 428               res = "PREVAILING_DEF_IRONLY";
 429               break;
 430             case LDPR_PREVAILING_DEF_IRONLY_EXP:
 431               res = "PREVAILING_DEF_IRONLY_EXP";
 432               break;
 433             case LDPR_PREEMPTED_REG:
 434               res = "PREEMPTED_REG";
 435               break;
 436             case LDPR_PREEMPTED_IR:
 437               res = "PREEMPTED_IR";
 438               break;
 439             case LDPR_RESOLVED_IR:
 440               res = "RESOLVED_IR";
 441               break;
 442             case LDPR_RESOLVED_EXEC:
 443               res = "RESOLVED_EXEC";
 444               break;
 445             case LDPR_RESOLVED_DYN:
 446               res = "RESOLVED_DYN";
 447               break;
 448             default:
 449               res = "?";
 450               break;
 451             }
 452           (*message)(LDPL_INFO, "%s: %s: %s", claimed_file->name,
 453                      claimed_file->syms[i].name, res);
 454         }
 455     }
 456
 457   if (add_input_file == NULL)
 458     {
 459       fprintf(stderr, "tv_add_input_file interface missing\n");
 460       return LDPS_ERR;
 461     }
 462   if (get_input_file == NULL)
 463     {
 464       fprintf(stderr, "tv_get_input_file interface missing\n");
 465       return LDPS_ERR;
 466     }
 467   if (release_input_file == NULL)
 468     {
 469       fprintf(stderr, "tv_release_input_file interface missing\n");
 470       return LDPS_ERR;
 471     }
 472
 473   for (claimed_file = first_claimed_file;
 474        claimed_file != NULL;
 475        claimed_file = claimed_file->next)
 476     {
 477       (*get_input_file) (claimed_file->handle, &file);
 478
 479       /* Look for the beginning of output from readelf -s.  */
 480       irfile = fdopen(file.fd, "r");
 481       (void)fseek(irfile, file.offset, SEEK_SET);
 482       end_offset = file.offset + file.filesize;
 483       len = fread(buf, 1, 13, irfile);
 484       if (len < 13 || strncmp(buf, "\nSymbol table", 13) != 0)
 485         {
 486           fprintf(stderr, "%s: can't re-read original input file\n",
 487                   claimed_file->name);
 488           return LDPS_ERR;
 489         }
 490
 491       /* Skip the two header lines.  */
 492       (void) fgets(buf, sizeof(buf), irfile);
 493       (void) fgets(buf, sizeof(buf), irfile);
 494
 495       filename = NULL;
 496       while (ftell(irfile) < end_offset
 497              && fgets(buf, sizeof(buf), irfile) != NULL)
 498         {
 499           parse_readelf_line(buf, &info);
 500
 501           /* Look for file name.  */
 502           if (strncmp(info.type, "FILE", 4) == 0)
 503             {
 504               len = strlen(info.name);
 505               p = malloc(len + 1);
 506               strncpy(p, info.name, len + 1);
 507               filename = p;
 508               break;
 509             }
 510         }
 511
 512       (*release_input_file) (claimed_file->handle);
 513
 514       if (filename == NULL)
 515         filename = claimed_file->name;
 516
 517       if (claimed_file->nsyms == 0)
 518         continue;
 519
 520       if (strlen(filename) >= sizeof(buf))
 521         {
 522           (*message)(LDPL_FATAL, "%s: filename too long", filename);
 523           return LDPS_ERR;
 524         }
 525       strcpy(buf, filename);
 526       p = strrchr(buf, '.');
 527       if (p == NULL
 528           || (strcmp(p, ".syms") != 0
 529               && strcmp(p, ".c") != 0
 530               && strcmp(p, ".cc") != 0))
 531         {
 532           (*message)(LDPL_FATAL, "%s: filename has unknown suffix",
 533                      filename);
 534           return LDPS_ERR;
 535         }
 536       p[1] = 'o';
 537       p[2] = '\0';
 538       (*message)(LDPL_INFO, "%s: adding new input file", buf);
 539       (*add_input_file)(buf);
 540     }
 541
 542   return LDPS_OK;
 543 }
 544
 545 enum ld_plugin_status
 546 cleanup_hook(void)
 547 {
 548   (*message)(LDPL_INFO, "cleanup hook called");
 549   return LDPS_OK;
 550 }
 551
 552 static void
 553 parse_readelf_line(char* p, struct sym_info* info)
 554 {
 555   int len;
 556
 557   p += strspn(p, " ");
 558
 559   /* Index field.  */
 560   p += strcspn(p, " ");
 561   p += strspn(p, " ");
 562
 563   /* Value field.  */
 564   p += strcspn(p, " ");
 565   p += strspn(p, " ");
 566
 567   /* Size field.  */
 568   info->size = atoi(p);
 569   p += strcspn(p, " ");
 570   p += strspn(p, " ");
 571
 572   /* Type field.  */
 573   info->type = p;
 574   p += strcspn(p, " ");
 575   p += strspn(p, " ");
 576
 577   /* Binding field.  */
 578   info->bind = p;
 579   p += strcspn(p, " ");
 580   p += strspn(p, " ");
 581
 582   /* Visibility field.  */
 583   info->vis = p;
 584   p += strcspn(p, " ");
 585   p += strspn(p, " ");
 586
 587   if (*p == '[')
 588     {
 589       /* Skip st_other.  */
 590       p += strcspn(p, "]");
 591       p += strspn(p, "] ");
 592     }
 593
 594   /* Section field.  */
 595   info->sect = p;
 596   p += strcspn(p, " ");
 597   p += strspn(p, " ");
 598
 599   /* Name field.  */
 600   /* FIXME:  Look for version.  */
 601   len = strlen(p);
 602   if (len == 0)
 603     p = NULL;
 604   else if (p[len-1] == '\n')
 605     p[--len] = '\0';
 606   info->name = p;
 607 }