gold/testsuite/plugin_test.c

   1 /* test_plugin.c -- simple linker plugin test
   2
   3    Copyright (C) 2008-2021 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   char* ver;
  50 };
  51
  52 static struct claimed_file* first_claimed_file = NULL;
  53 static struct claimed_file* last_claimed_file = NULL;
  54
  55 static ld_plugin_register_claim_file register_claim_file_hook = NULL;
  56 static ld_plugin_register_all_symbols_read register_all_symbols_read_hook = NULL;
  57 static ld_plugin_register_cleanup register_cleanup_hook = NULL;
  58 static ld_plugin_add_symbols add_symbols = NULL;
  59 static ld_plugin_get_symbols get_symbols = NULL;
  60 static ld_plugin_get_symbols get_symbols_v2 = NULL;
  61 static ld_plugin_get_symbols get_symbols_v3 = NULL;
  62 static ld_plugin_add_input_file add_input_file = NULL;
  63 static ld_plugin_message message = NULL;
  64 static ld_plugin_get_input_file get_input_file = NULL;
  65 static ld_plugin_release_input_file release_input_file = NULL;
  66 static ld_plugin_get_input_section_count get_input_section_count = NULL;
  67 static ld_plugin_get_input_section_type get_input_section_type = NULL;
  68 static ld_plugin_get_input_section_name get_input_section_name = NULL;
  69 static ld_plugin_get_input_section_contents get_input_section_contents = NULL;
  70 static ld_plugin_update_section_order update_section_order = NULL;
  71 static ld_plugin_allow_section_ordering allow_section_ordering = NULL;
  72 static ld_plugin_get_wrap_symbols get_wrap_symbols = NULL;
  73
  74 #define MAXOPTS 10
  75
  76 static const char *opts[MAXOPTS];
  77 static int nopts = 0;
  78
  79 enum ld_plugin_status onload(struct ld_plugin_tv *tv);
  80 enum ld_plugin_status claim_file_hook(const struct ld_plugin_input_file *file,
  81                                       int *claimed);
  82 enum ld_plugin_status all_symbols_read_hook(void);
  83 enum ld_plugin_status cleanup_hook(void);
  84
  85 static void parse_readelf_line(char*, struct sym_info*);
  86
  87 enum ld_plugin_status
  88 onload(struct ld_plugin_tv *tv)
  89 {
  90   struct ld_plugin_tv *entry;
  91   int api_version = 0;
  92   int gold_version = 0;
  93   int i;
  94
  95   for (entry = tv; entry->tv_tag != LDPT_NULL; ++entry)
  96     {
  97       switch (entry->tv_tag)
  98         {
  99         case LDPT_API_VERSION:
 100           api_version = entry->tv_u.tv_val;
 101           break;
 102         case LDPT_GOLD_VERSION:
 103           gold_version = entry->tv_u.tv_val;
 104           break;
 105         case LDPT_LINKER_OUTPUT:
 106           break;
 107         case LDPT_OPTION:
 108           if (nopts < MAXOPTS)
 109             opts[nopts++] = entry->tv_u.tv_string;
 110           break;
 111         case LDPT_REGISTER_CLAIM_FILE_HOOK:
 112           register_claim_file_hook = entry->tv_u.tv_register_claim_file;
 113           break;
 114         case LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK:
 115           register_all_symbols_read_hook =
 116             entry->tv_u.tv_register_all_symbols_read;
 117           break;
 118         case LDPT_REGISTER_CLEANUP_HOOK:
 119           register_cleanup_hook = entry->tv_u.tv_register_cleanup;
 120           break;
 121         case LDPT_ADD_SYMBOLS:
 122           add_symbols = entry->tv_u.tv_add_symbols;
 123           break;
 124         case LDPT_GET_SYMBOLS:
 125           get_symbols = entry->tv_u.tv_get_symbols;
 126           break;
 127         case LDPT_GET_SYMBOLS_V2:
 128           get_symbols_v2 = entry->tv_u.tv_get_symbols;
 129           break;
 130         case LDPT_GET_SYMBOLS_V3:
 131           get_symbols_v3 = entry->tv_u.tv_get_symbols;
 132           break;
 133         case LDPT_ADD_INPUT_FILE:
 134           add_input_file = entry->tv_u.tv_add_input_file;
 135           break;
 136         case LDPT_MESSAGE:
 137           message = entry->tv_u.tv_message;
 138           break;
 139         case LDPT_GET_INPUT_FILE:
 140           get_input_file = entry->tv_u.tv_get_input_file;
 141           break;
 142         case LDPT_RELEASE_INPUT_FILE:
 143           release_input_file = entry->tv_u.tv_release_input_file;
 144           break;
 145         case LDPT_GET_INPUT_SECTION_COUNT:
 146           get_input_section_count = *entry->tv_u.tv_get_input_section_count;
 147           break;
 148         case LDPT_GET_INPUT_SECTION_TYPE:
 149           get_input_section_type = *entry->tv_u.tv_get_input_section_type;
 150           break;
 151         case LDPT_GET_INPUT_SECTION_NAME:
 152           get_input_section_name = *entry->tv_u.tv_get_input_section_name;
 153           break;
 154         case LDPT_GET_INPUT_SECTION_CONTENTS:
 155           get_input_section_contents = *entry->tv_u.tv_get_input_section_contents;
 156           break;
 157         case LDPT_UPDATE_SECTION_ORDER:
 158           update_section_order = *entry->tv_u.tv_update_section_order;
 159           break;
 160         case LDPT_ALLOW_SECTION_ORDERING:
 161           allow_section_ordering = *entry->tv_u.tv_allow_section_ordering;
 162           break;
 163         case LDPT_GET_WRAP_SYMBOLS:
 164           get_wrap_symbols = *entry->tv_u.tv_get_wrap_symbols;
 165           break;
 166         default:
 167           break;
 168         }
 169     }
 170
 171   if (message == NULL)
 172     {
 173       fprintf(stderr, "tv_message interface missing\n");
 174       return LDPS_ERR;
 175     }
 176
 177   if (register_claim_file_hook == NULL)
 178     {
 179       fprintf(stderr, "tv_register_claim_file_hook interface missing\n");
 180       return LDPS_ERR;
 181     }
 182
 183   if (register_all_symbols_read_hook == NULL)
 184     {
 185       fprintf(stderr, "tv_register_all_symbols_read_hook interface missing\n");
 186       return LDPS_ERR;
 187     }
 188
 189   if (register_cleanup_hook == NULL)
 190     {
 191       fprintf(stderr, "tv_register_cleanup_hook interface missing\n");
 192       return LDPS_ERR;
 193     }
 194
 195   (*message)(LDPL_INFO, "API version:   %d", api_version);
 196   (*message)(LDPL_INFO, "gold version:  %d", gold_version);
 197
 198   for (i = 0; i < nopts; ++i)
 199     (*message)(LDPL_INFO, "option: %s", opts[i]);
 200
 201   if ((*register_claim_file_hook)(claim_file_hook) != LDPS_OK)
 202     {
 203       (*message)(LDPL_ERROR, "error registering claim file hook");
 204       return LDPS_ERR;
 205     }
 206
 207   if ((*register_all_symbols_read_hook)(all_symbols_read_hook) != LDPS_OK)
 208     {
 209       (*message)(LDPL_ERROR, "error registering all symbols read hook");
 210       return LDPS_ERR;
 211     }
 212
 213   if ((*register_cleanup_hook)(cleanup_hook) != LDPS_OK)
 214     {
 215       (*message)(LDPL_ERROR, "error registering cleanup hook");
 216       return LDPS_ERR;
 217     }
 218
 219   if (get_input_section_count == NULL)
 220     {
 221       fprintf(stderr, "tv_get_input_section_count interface missing\n");
 222       return LDPS_ERR;
 223     }
 224
 225   if (get_input_section_type == NULL)
 226     {
 227       fprintf(stderr, "tv_get_input_section_type interface missing\n");
 228       return LDPS_ERR;
 229     }
 230
 231   if (get_input_section_name == NULL)
 232     {
 233       fprintf(stderr, "tv_get_input_section_name interface missing\n");
 234       return LDPS_ERR;
 235     }
 236
 237   if (get_input_section_contents == NULL)
 238     {
 239       fprintf(stderr, "tv_get_input_section_contents interface missing\n");
 240       return LDPS_ERR;
 241     }
 242
 243   if (update_section_order == NULL)
 244     {
 245       fprintf(stderr, "tv_update_section_order interface missing\n");
 246       return LDPS_ERR;
 247     }
 248
 249   if (allow_section_ordering == NULL)
 250     {
 251       fprintf(stderr, "tv_allow_section_ordering interface missing\n");
 252       return LDPS_ERR;
 253     }
 254
 255   if (get_wrap_symbols == NULL)
 256     {
 257       fprintf(stderr, "tv_get_wrap_symbols interface missing\n");
 258       return LDPS_ERR;
 259     }
 260   else
 261     {
 262       const char **wrap_symbols;
 263       uint64_t count = 0;
 264       if (get_wrap_symbols(&count, &wrap_symbols) == LDPS_OK)
 265         {
 266           (*message)(LDPL_INFO, "Number of wrap symbols = %lu", count);
 267           for (; count > 0; --count)
 268             (*message)(LDPL_INFO, "Wrap symbol %s", wrap_symbols[count - 1]);
 269         }
 270       else
 271         {
 272           fprintf(stderr, "tv_get_wrap_symbols interface call failed\n");
 273           return LDPS_ERR;
 274         }
 275     }
 276
 277   return LDPS_OK;
 278 }
 279
 280 enum ld_plugin_status
 281 claim_file_hook (const struct ld_plugin_input_file* file, int* claimed)
 282 {
 283   int len;
 284   off_t end_offset;
 285   char buf[160];
 286   struct claimed_file* claimed_file;
 287   struct ld_plugin_symbol* syms;
 288   int nsyms = 0;
 289   int maxsyms = 0;
 290   FILE* irfile;
 291   struct sym_info info;
 292   int weak;
 293   int def;
 294   int vis;
 295   int is_comdat;
 296   int i;
 297   int irfile_was_opened = 0;
 298   char syms_name[80];
 299
 300   (*message)(LDPL_INFO,
 301              "%s: claim file hook called (offset = %ld, size = %ld)",
 302              file->name, (long)file->offset, (long)file->filesize);
 303
 304   /* Look for matching syms file for an archive member.  */
 305   if (file->offset == 0)
 306     snprintf(syms_name, sizeof(syms_name), "%s.syms", file->name);
 307   else
 308     snprintf(syms_name, sizeof(syms_name), "%s-%d.syms",
 309              file->name, (int)file->offset);
 310   irfile = fopen(syms_name, "r");
 311   if (irfile != NULL)
 312     {
 313       irfile_was_opened = 1;
 314       end_offset = 1 << 20;
 315     }
 316
 317   /* Otherwise, see if the file itself is a syms file.  */
 318   if (!irfile_was_opened)
 319     {
 320       irfile = fdopen(file->fd, "r");
 321       (void)fseek(irfile, file->offset, SEEK_SET);
 322       end_offset = file->offset + file->filesize;
 323     }
 324
 325   /* Look for the beginning of output from readelf -s.  */
 326   len = fread(buf, 1, 13, irfile);
 327   if (len < 13 || strncmp(buf, "\nSymbol table", 13) != 0)
 328     return LDPS_OK;
 329
 330   /* Skip the two header lines.  */
 331   (void) fgets(buf, sizeof(buf), irfile);
 332   (void) fgets(buf, sizeof(buf), irfile);
 333
 334   if (add_symbols == NULL)
 335     {
 336       fprintf(stderr, "tv_add_symbols interface missing\n");
 337       return LDPS_ERR;
 338     }
 339
 340   /* Parse the output from readelf. The columns are:
 341      Index Value Size Type Binding Visibility Section Name.  */
 342   syms = (struct ld_plugin_symbol*)malloc(sizeof(struct ld_plugin_symbol) * 8);
 343   if (syms == NULL)
 344     return LDPS_ERR;
 345   maxsyms = 8;
 346   while (ftell(irfile) < end_offset
 347          && fgets(buf, sizeof(buf), irfile) != NULL)
 348     {
 349       parse_readelf_line(buf, &info);
 350
 351       /* Ignore local symbols.  */
 352       if (strncmp(info.bind, "LOCAL", 5) == 0)
 353         continue;
 354
 355       weak = strncmp(info.bind, "WEAK", 4) == 0;
 356       if (strncmp(info.sect, "UND", 3) == 0)
 357         def = weak ? LDPK_WEAKUNDEF : LDPK_UNDEF;
 358       else if (strncmp(info.sect, "COM", 3) == 0)
 359         def = LDPK_COMMON;
 360       else
 361         def = weak ? LDPK_WEAKDEF : LDPK_DEF;
 362
 363       if (strncmp(info.vis, "INTERNAL", 8) == 0)
 364         vis = LDPV_INTERNAL;
 365       else if (strncmp(info.vis, "HIDDEN", 6) == 0)
 366         vis = LDPV_HIDDEN;
 367       else if (strncmp(info.vis, "PROTECTED", 9) == 0)
 368         vis = LDPV_PROTECTED;
 369       else
 370         vis = LDPV_DEFAULT;
 371
 372       /* If the symbol is listed in the options list, special-case
 373          it as a comdat symbol.  */
 374       is_comdat = 0;
 375       for (i = 0; i < nopts; ++i)
 376         {
 377           if (info.name != NULL && strcmp(info.name, opts[i]) == 0)
 378             {
 379               is_comdat = 1;
 380               break;
 381             }
 382         }
 383
 384       if (nsyms >= maxsyms)
 385         {
 386           syms = (struct ld_plugin_symbol*)
 387             realloc(syms, sizeof(struct ld_plugin_symbol) * maxsyms * 2);
 388           if (syms == NULL)
 389             return LDPS_ERR;
 390           maxsyms *= 2;
 391         }
 392
 393       if (info.name == NULL)
 394         syms[nsyms].name = NULL;
 395       else
 396         {
 397           len = strlen(info.name);
 398           syms[nsyms].name = malloc(len + 1);
 399           strncpy(syms[nsyms].name, info.name, len + 1);
 400         }
 401       if (info.ver == NULL)
 402         syms[nsyms].version = NULL;
 403       else
 404         {
 405           len = strlen(info.ver);
 406           syms[nsyms].version = malloc(len + 1);
 407           strncpy(syms[nsyms].version, info.ver, len + 1);
 408         }
 409       syms[nsyms].def = def;
 410       syms[nsyms].visibility = vis;
 411       syms[nsyms].size = info.size;
 412       syms[nsyms].comdat_key = is_comdat ? syms[nsyms].name : NULL;
 413       syms[nsyms].resolution = LDPR_UNKNOWN;
 414       ++nsyms;
 415     }
 416
 417   claimed_file = (struct claimed_file*) malloc(sizeof(struct claimed_file));
 418   if (claimed_file == NULL)
 419     return LDPS_ERR;
 420
 421   claimed_file->name = file->name;
 422   claimed_file->handle = file->handle;
 423   claimed_file->nsyms = nsyms;
 424   claimed_file->syms = syms;
 425   claimed_file->next = NULL;
 426   if (last_claimed_file == NULL)
 427     first_claimed_file = claimed_file;
 428   else
 429     last_claimed_file->next = claimed_file;
 430   last_claimed_file = claimed_file;
 431
 432   (*message)(LDPL_INFO, "%s: claiming file, adding %d symbols",
 433              file->name, nsyms);
 434
 435   if (nsyms > 0)
 436     (*add_symbols)(file->handle, nsyms, syms);
 437
 438   *claimed = 1;
 439   if (irfile_was_opened)
 440     fclose(irfile);
 441   return LDPS_OK;
 442 }
 443
 444 enum ld_plugin_status
 445 all_symbols_read_hook(void)
 446 {
 447   int i;
 448   const char* res;
 449   struct claimed_file* claimed_file;
 450   struct ld_plugin_input_file file;
 451   FILE* irfile;
 452   off_t end_offset;
 453   struct sym_info info;
 454   int len;
 455   char buf[160];
 456   char* p;
 457   const char* filename;
 458
 459   (*message)(LDPL_INFO, "all symbols read hook called");
 460
 461   if (get_symbols_v3 == NULL)
 462     {
 463       fprintf(stderr, "tv_get_symbols (v3) interface missing\n");
 464       return LDPS_ERR;
 465     }
 466
 467   for (claimed_file = first_claimed_file;
 468        claimed_file != NULL;
 469        claimed_file = claimed_file->next)
 470     {
 471       enum ld_plugin_status status = (*get_symbols_v3)(
 472           claimed_file->handle, claimed_file->nsyms, claimed_file->syms);
 473       if (status == LDPS_NO_SYMS)
 474         {
 475           (*message)(LDPL_INFO, "%s: no symbols", claimed_file->name);
 476           continue;
 477         }
 478
 479       for (i = 0; i < claimed_file->nsyms; ++i)
 480         {
 481           switch (claimed_file->syms[i].resolution)
 482             {
 483             case LDPR_UNKNOWN:
 484               res = "UNKNOWN";
 485               break;
 486             case LDPR_UNDEF:
 487               res = "UNDEF";
 488               break;
 489             case LDPR_PREVAILING_DEF:
 490               res = "PREVAILING_DEF_REG";
 491               break;
 492             case LDPR_PREVAILING_DEF_IRONLY:
 493               res = "PREVAILING_DEF_IRONLY";
 494               break;
 495             case LDPR_PREVAILING_DEF_IRONLY_EXP:
 496               res = "PREVAILING_DEF_IRONLY_EXP";
 497               break;
 498             case LDPR_PREEMPTED_REG:
 499               res = "PREEMPTED_REG";
 500               break;
 501             case LDPR_PREEMPTED_IR:
 502               res = "PREEMPTED_IR";
 503               break;
 504             case LDPR_RESOLVED_IR:
 505               res = "RESOLVED_IR";
 506               break;
 507             case LDPR_RESOLVED_EXEC:
 508               res = "RESOLVED_EXEC";
 509               break;
 510             case LDPR_RESOLVED_DYN:
 511               res = "RESOLVED_DYN";
 512               break;
 513             default:
 514               res = "?";
 515               break;
 516             }
 517           (*message)(LDPL_INFO, "%s: %s: %s", claimed_file->name,
 518                      claimed_file->syms[i].name, res);
 519         }
 520     }
 521
 522   if (add_input_file == NULL)
 523     {
 524       fprintf(stderr, "tv_add_input_file interface missing\n");
 525       return LDPS_ERR;
 526     }
 527   if (get_input_file == NULL)
 528     {
 529       fprintf(stderr, "tv_get_input_file interface missing\n");
 530       return LDPS_ERR;
 531     }
 532   if (release_input_file == NULL)
 533     {
 534       fprintf(stderr, "tv_release_input_file interface missing\n");
 535       return LDPS_ERR;
 536     }
 537
 538   for (claimed_file = first_claimed_file;
 539        claimed_file != NULL;
 540        claimed_file = claimed_file->next)
 541     {
 542       int irfile_was_opened = 0;
 543       char syms_name[80];
 544
 545       (*get_input_file) (claimed_file->handle, &file);
 546
 547       if (file.offset == 0)
 548         snprintf(syms_name, sizeof(syms_name), "%s.syms", file.name);
 549       else
 550         snprintf(syms_name, sizeof(syms_name), "%s-%d.syms",
 551                  file.name, (int)file.offset);
 552       irfile = fopen(syms_name, "r");
 553       if (irfile != NULL)
 554         {
 555           irfile_was_opened = 1;
 556           end_offset = 1 << 20;
 557         }
 558
 559       if (!irfile_was_opened)
 560         {
 561           irfile = fdopen(file.fd, "r");
 562           (void)fseek(irfile, file.offset, SEEK_SET);
 563           end_offset = file.offset + file.filesize;
 564         }
 565
 566       /* Look for the beginning of output from readelf -s.  */
 567       len = fread(buf, 1, 13, irfile);
 568       if (len < 13 || strncmp(buf, "\nSymbol table", 13) != 0)
 569         {
 570           fprintf(stderr, "%s: can't re-read original input file\n",
 571                   claimed_file->name);
 572           return LDPS_ERR;
 573         }
 574
 575       /* Skip the two header lines.  */
 576       (void) fgets(buf, sizeof(buf), irfile);
 577       (void) fgets(buf, sizeof(buf), irfile);
 578
 579       filename = NULL;
 580       while (ftell(irfile) < end_offset
 581              && fgets(buf, sizeof(buf), irfile) != NULL)
 582         {
 583           parse_readelf_line(buf, &info);
 584
 585           /* Look for file name.  */
 586           if (strncmp(info.type, "FILE", 4) == 0)
 587             {
 588               len = strlen(info.name);
 589               p = malloc(len + 1);
 590               strncpy(p, info.name, len + 1);
 591               filename = p;
 592               break;
 593             }
 594         }
 595
 596       if (irfile_was_opened)
 597         fclose(irfile);
 598
 599       (*release_input_file) (claimed_file->handle);
 600
 601       if (filename == NULL)
 602         filename = claimed_file->name;
 603
 604       if (claimed_file->nsyms == 0)
 605         continue;
 606
 607       if (strlen(filename) >= sizeof(buf))
 608         {
 609           (*message)(LDPL_FATAL, "%s: filename too long", filename);
 610           return LDPS_ERR;
 611         }
 612       strcpy(buf, filename);
 613       p = strrchr(buf, '.');
 614       if (p == NULL
 615           || (strcmp(p, ".syms") != 0
 616               && strcmp(p, ".c") != 0
 617               && strcmp(p, ".cc") != 0))
 618         {
 619           (*message)(LDPL_FATAL, "%s: filename has unknown suffix",
 620                      filename);
 621           return LDPS_ERR;
 622         }
 623       p[1] = 'o';
 624       p[2] = '\0';
 625       (*message)(LDPL_INFO, "%s: adding new input file", buf);
 626       (*add_input_file)(buf);
 627     }
 628
 629   return LDPS_OK;
 630 }
 631
 632 enum ld_plugin_status
 633 cleanup_hook(void)
 634 {
 635   (*message)(LDPL_INFO, "cleanup hook called");
 636   return LDPS_OK;
 637 }
 638
 639 static void
 640 parse_readelf_line(char* p, struct sym_info* info)
 641 {
 642   int len;
 643
 644   p += strspn(p, " ");
 645
 646   /* Index field.  */
 647   p += strcspn(p, " ");
 648   p += strspn(p, " ");
 649
 650   /* Value field.  */
 651   p += strcspn(p, " ");
 652   p += strspn(p, " ");
 653
 654   /* Size field.  */
 655   info->size = atoi(p);
 656   p += strcspn(p, " ");
 657   p += strspn(p, " ");
 658
 659   /* Type field.  */
 660   info->type = p;
 661   p += strcspn(p, " ");
 662   p += strspn(p, " ");
 663
 664   /* Binding field.  */
 665   info->bind = p;
 666   p += strcspn(p, " ");
 667   p += strspn(p, " ");
 668
 669   /* Visibility field.  */
 670   info->vis = p;
 671   p += strcspn(p, " ");
 672   p += strspn(p, " ");
 673
 674   if (*p == '[')
 675     {
 676       /* Skip st_other.  */
 677       p += strcspn(p, "]");
 678       p += strspn(p, "] ");
 679     }
 680
 681   /* Section field.  */
 682   info->sect = p;
 683   p += strcspn(p, " ");
 684   p += strspn(p, " ");
 685
 686   /* Name field.  */
 687   len = strcspn(p, "@\n");
 688   if (len > 0 && p[len] == '@')
 689     {
 690       /* Get the symbol version.  */
 691       char* vp = p + len;
 692       int vlen;
 693
 694       vp += strspn(vp, "@");
 695       vlen = strcspn(vp, "\n");
 696       vp[vlen] = '\0';
 697       if (vlen > 0)
 698         info->ver = vp;
 699       else
 700         info->ver = NULL;
 701     }
 702   else
 703     info->ver = NULL;
 704   p[len] = '\0';
 705   if (len > 0)
 706     info->name = p;
 707   else
 708     info->name = NULL;
 709 }