tccrun.c

   1 /*
   2  *  TCC - Tiny C Compiler - Support for -run switch
   3  *
   4  *  Copyright (c) 2001-2004 Fabrice Bellard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library 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 GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "tcc.h"
  22
  23 /* only native compiler supports -run */
  24 #ifdef TCC_IS_NATIVE
  25
  26 #ifdef CONFIG_TCC_BACKTRACE
  27 ST_DATA int rt_num_callers = 6;
  28 ST_DATA const char **rt_bound_error_msg;
  29 ST_DATA void *rt_prog_main;
  30 #endif
  31
  32 #ifdef _WIN32
  33 #define ucontext_t CONTEXT
  34 #endif
  35
  36 static void set_pages_executable(void *ptr, unsigned long length);
  37 static void set_exception_handler(void);
  38 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level);
  39 static void rt_error(ucontext_t *uc, const char *fmt, ...);
  40 static int tcc_relocate_ex(TCCState *s1, void *ptr);
  41
  42 #ifdef _WIN64
  43 static void win64_add_function_table(TCCState *s1);
  44 #endif
  45
  46 /* ------------------------------------------------------------- */
  47 /* Do all relocations (needed before using tcc_get_symbol())
  48    Returns -1 on error. */
  49
  50 LIBTCCAPI int tcc_relocate(TCCState *s1, void *ptr)
  51 {
  52     int ret;
  53
  54     if (TCC_RELOCATE_AUTO != ptr)
  55         return tcc_relocate_ex(s1, ptr);
  56
  57     ret = tcc_relocate_ex(s1, NULL);
  58     if (ret < 0)
  59         return ret;
  60
  61 #ifdef HAVE_SELINUX
  62     {   /* Use mmap instead of malloc for Selinux.  Ref:
  63            http://www.gnu.org/s/libc/manual/html_node/File-Size.html */
  64
  65         char tmpfname[] = "/tmp/.tccrunXXXXXX";
  66         int fd = mkstemp (tmpfname);
  67
  68         s1->mem_size = ret;
  69         unlink (tmpfname);
  70         ftruncate (fd, s1->mem_size);
  71
  72         s1->write_mem = mmap (NULL, ret, PROT_READ|PROT_WRITE,
  73             MAP_SHARED, fd, 0);
  74         if (s1->write_mem == MAP_FAILED)
  75             tcc_error("/tmp not writeable");
  76
  77         s1->runtime_mem = mmap (NULL, ret, PROT_READ|PROT_EXEC,
  78             MAP_SHARED, fd, 0);
  79         if (s1->runtime_mem == MAP_FAILED)
  80             tcc_error("/tmp not executable");
  81
  82         ret = tcc_relocate_ex(s1, s1->write_mem);
  83     }
  84 #else
  85     s1->runtime_mem = tcc_malloc(ret);
  86     ret = tcc_relocate_ex(s1, s1->runtime_mem);
  87 #endif
  88     return ret;
  89 }
  90
  91 /* launch the compiled program with the given arguments */
  92 LIBTCCAPI int tcc_run(TCCState *s1, int argc, char **argv)
  93 {
  94     int (*prog_main)(int, char **);
  95     int ret;
  96
  97     if (tcc_relocate(s1, TCC_RELOCATE_AUTO) < 0)
  98         return -1;
  99
 100     prog_main = tcc_get_symbol_err(s1, "main");
 101
 102 #ifdef CONFIG_TCC_BACKTRACE
 103     if (s1->do_debug) {
 104         set_exception_handler();
 105         rt_prog_main = prog_main;
 106     }
 107 #endif
 108
 109 #ifdef CONFIG_TCC_BCHECK
 110     if (s1->do_bounds_check) {
 111         void (*bound_init)(void);
 112         void (*bound_exit)(void);
 113         /* set error function */
 114         rt_bound_error_msg = tcc_get_symbol_err(s1, "__bound_error_msg");
 115         /* XXX: use .init section so that it also work in binary ? */
 116         bound_init = tcc_get_symbol_err(s1, "__bound_init");
 117         bound_exit = tcc_get_symbol_err(s1, "__bound_exit");
 118         bound_init();
 119         ret = (*prog_main)(argc, argv);
 120         bound_exit();
 121     } else
 122 #endif
 123         ret = (*prog_main)(argc, argv);
 124     return ret;
 125 }
 126
 127 /* relocate code. Return -1 on error, required size if ptr is NULL,
 128    otherwise copy code into buffer passed by the caller */
 129 static int tcc_relocate_ex(TCCState *s1, void *ptr)
 130 {
 131     Section *s;
 132     unsigned long offset, length;
 133     addr_t mem;
 134     int i;
 135
 136     if (NULL == ptr) {
 137         s1->nb_errors = 0;
 138 #ifdef TCC_TARGET_PE
 139         pe_output_file(s1, NULL);
 140 #else
 141         tcc_add_runtime(s1);
 142         relocate_common_syms();
 143         tcc_add_linker_symbols(s1);
 144         build_got_entries(s1);
 145 #endif
 146         if (s1->nb_errors)
 147             return -1;
 148     }
 149
 150     offset = 0, mem = (addr_t)ptr;
 151     for(i = 1; i < s1->nb_sections; i++) {
 152         s = s1->sections[i];
 153         if (0 == (s->sh_flags & SHF_ALLOC))
 154             continue;
 155         length = s->data_offset;
 156         s->sh_addr = mem ? (mem + offset + 15) & ~15 : 0;
 157         offset = (offset + length + 15) & ~15;
 158     }
 159     offset += 16;
 160
 161     /* relocate symbols */
 162     relocate_syms(s1, 1);
 163     if (s1->nb_errors)
 164         return -1;
 165
 166 #ifdef TCC_HAS_RUNTIME_PLTGOT
 167     s1->runtime_plt_and_got_offset = 0;
 168     s1->runtime_plt_and_got = (char *)(mem + offset);
 169     /* double the size of the buffer for got and plt entries
 170        XXX: calculate exact size for them? */
 171     offset *= 2;
 172 #endif
 173
 174     if (0 == mem)
 175         return offset;
 176
 177     /* relocate each section */
 178     for(i = 1; i < s1->nb_sections; i++) {
 179         s = s1->sections[i];
 180         if (s->reloc)
 181             relocate_section(s1, s);
 182     }
 183
 184     for(i = 1; i < s1->nb_sections; i++) {
 185         s = s1->sections[i];
 186         if (0 == (s->sh_flags & SHF_ALLOC))
 187             continue;
 188         length = s->data_offset;
 189         // printf("%-12s %08x %04x\n", s->name, s->sh_addr, length);
 190         ptr = (void*)s->sh_addr;
 191         if (NULL == s->data || s->sh_type == SHT_NOBITS)
 192             memset(ptr, 0, length);
 193         else
 194             memcpy(ptr, s->data, length);
 195         /* mark executable sections as executable in memory */
 196         if (s->sh_flags & SHF_EXECINSTR)
 197             set_pages_executable(ptr, length);
 198     }
 199
 200 #ifdef TCC_HAS_RUNTIME_PLTGOT
 201     set_pages_executable(s1->runtime_plt_and_got,
 202                          s1->runtime_plt_and_got_offset);
 203 #endif
 204
 205 #ifdef _WIN64
 206     win64_add_function_table(s1);
 207 #endif
 208     return 0;
 209 }
 210
 211 /* ------------------------------------------------------------- */
 212 /* allow to run code in memory */
 213
 214 static void set_pages_executable(void *ptr, unsigned long length)
 215 {
 216 #ifdef _WIN32
 217     unsigned long old_protect;
 218     VirtualProtect(ptr, length, PAGE_EXECUTE_READWRITE, &old_protect);
 219 #else
 220 #ifndef PAGESIZE
 221 # define PAGESIZE 4096
 222 #endif
 223     addr_t start, end;
 224     start = (addr_t)ptr & ~(PAGESIZE - 1);
 225     end = (addr_t)ptr + length;
 226     end = (end + PAGESIZE - 1) & ~(PAGESIZE - 1);
 227     mprotect((void *)start, end - start, PROT_READ | PROT_WRITE | PROT_EXEC);
 228 #endif
 229 }
 230
 231 /* ------------------------------------------------------------- */
 232 #ifdef CONFIG_TCC_BACKTRACE
 233
 234 ST_FUNC void tcc_set_num_callers(int n)
 235 {
 236     rt_num_callers = n;
 237 }
 238
 239 /* print the position in the source file of PC value 'pc' by reading
 240    the stabs debug information */
 241 static addr_t rt_printline(addr_t wanted_pc, const char *msg)
 242 {
 243     char func_name[128], last_func_name[128];
 244     addr_t func_addr, last_pc, pc;
 245     const char *incl_files[INCLUDE_STACK_SIZE];
 246     int incl_index, len, last_line_num, i;
 247     const char *str, *p;
 248
 249     Stab_Sym *stab_sym = NULL, *stab_sym_end, *sym;
 250     int stab_len = 0;
 251     char *stab_str = NULL;
 252
 253     if (stab_section) {
 254         stab_len = stab_section->data_offset;
 255         stab_sym = (Stab_Sym *)stab_section->data;
 256         stab_str = stabstr_section->data;
 257     }
 258
 259     func_name[0] = '\0';
 260     func_addr = 0;
 261     incl_index = 0;
 262     last_func_name[0] = '\0';
 263     last_pc = (addr_t)-1;
 264     last_line_num = 1;
 265
 266     if (!stab_sym)
 267         goto no_stabs;
 268
 269     stab_sym_end = (Stab_Sym*)((char*)stab_sym + stab_len);
 270     for (sym = stab_sym + 1; sym < stab_sym_end; ++sym) {
 271         switch(sym->n_type) {
 272             /* function start or end */
 273         case N_FUN:
 274             if (sym->n_strx == 0) {
 275                 /* we test if between last line and end of function */
 276                 pc = sym->n_value + func_addr;
 277                 if (wanted_pc >= last_pc && wanted_pc < pc)
 278                     goto found;
 279                 func_name[0] = '\0';
 280                 func_addr = 0;
 281             } else {
 282                 str = stab_str + sym->n_strx;
 283                 p = strchr(str, ':');
 284                 if (!p) {
 285                     pstrcpy(func_name, sizeof(func_name), str);
 286                 } else {
 287                     len = p - str;
 288                     if (len > sizeof(func_name) - 1)
 289                         len = sizeof(func_name) - 1;
 290                     memcpy(func_name, str, len);
 291                     func_name[len] = '\0';
 292                 }
 293                 func_addr = sym->n_value;
 294             }
 295             break;
 296             /* line number info */
 297         case N_SLINE:
 298             pc = sym->n_value + func_addr;
 299             if (wanted_pc >= last_pc && wanted_pc < pc)
 300                 goto found;
 301             last_pc = pc;
 302             last_line_num = sym->n_desc;
 303             /* XXX: slow! */
 304             strcpy(last_func_name, func_name);
 305             break;
 306             /* include files */
 307         case N_BINCL:
 308             str = stab_str + sym->n_strx;
 309         add_incl:
 310             if (incl_index < INCLUDE_STACK_SIZE) {
 311                 incl_files[incl_index++] = str;
 312             }
 313             break;
 314         case N_EINCL:
 315             if (incl_index > 1)
 316                 incl_index--;
 317             break;
 318         case N_SO:
 319             if (sym->n_strx == 0) {
 320                 incl_index = 0; /* end of translation unit */
 321             } else {
 322                 str = stab_str + sym->n_strx;
 323                 /* do not add path */
 324                 len = strlen(str);
 325                 if (len > 0 && str[len - 1] != '/')
 326                     goto add_incl;
 327             }
 328             break;
 329         }
 330     }
 331
 332 no_stabs:
 333     /* second pass: we try symtab symbols (no line number info) */
 334     incl_index = 0;
 335     if (symtab_section)
 336     {
 337         ElfW(Sym) *sym, *sym_end;
 338         int type;
 339
 340         sym_end = (ElfW(Sym) *)(symtab_section->data + symtab_section->data_offset);
 341         for(sym = (ElfW(Sym) *)symtab_section->data + 1;
 342             sym < sym_end;
 343             sym++) {
 344             type = ELFW(ST_TYPE)(sym->st_info);
 345             if (type == STT_FUNC || type == STT_GNU_IFUNC) {
 346                 if (wanted_pc >= sym->st_value &&
 347                     wanted_pc < sym->st_value + sym->st_size) {
 348                     pstrcpy(last_func_name, sizeof(last_func_name),
 349                             strtab_section->data + sym->st_name);
 350                     func_addr = sym->st_value;
 351                     goto found;
 352                 }
 353             }
 354         }
 355     }
 356     /* did not find any info: */
 357     fprintf(stderr, "%s %p ???\n", msg, (void*)wanted_pc);
 358     fflush(stderr);
 359     return 0;
 360  found:
 361     i = incl_index;
 362     if (i > 0)
 363         fprintf(stderr, "%s:%d: ", incl_files[--i], last_line_num);
 364     fprintf(stderr, "%s %p", msg, (void*)wanted_pc);
 365     if (last_func_name[0] != '\0')
 366         fprintf(stderr, " %s()", last_func_name);
 367     if (--i >= 0) {
 368         fprintf(stderr, " (included from ");
 369         for (;;) {
 370             fprintf(stderr, "%s", incl_files[i]);
 371             if (--i < 0)
 372                 break;
 373             fprintf(stderr, ", ");
 374         }
 375         fprintf(stderr, ")");
 376     }
 377     fprintf(stderr, "\n");
 378     fflush(stderr);
 379     return func_addr;
 380 }
 381
 382 /* emit a run time error at position 'pc' */
 383 static void rt_error(ucontext_t *uc, const char *fmt, ...)
 384 {
 385     va_list ap;
 386     addr_t pc;
 387     int i;
 388
 389     fprintf(stderr, "Runtime error: ");
 390     va_start(ap, fmt);
 391     vfprintf(stderr, fmt, ap);
 392     va_end(ap);
 393     fprintf(stderr, "\n");
 394
 395     for(i=0;i<rt_num_callers;i++) {
 396         if (rt_get_caller_pc(&pc, uc, i) < 0)
 397             break;
 398         pc = rt_printline(pc, i ? "by" : "at");
 399         if (pc == (addr_t)rt_prog_main && pc)
 400             break;
 401     }
 402 }
 403
 404 /* ------------------------------------------------------------- */
 405 #ifndef _WIN32
 406
 407 /* signal handler for fatal errors */
 408 static void sig_error(int signum, siginfo_t *siginf, void *puc)
 409 {
 410     ucontext_t *uc = puc;
 411
 412     switch(signum) {
 413     case SIGFPE:
 414         switch(siginf->si_code) {
 415         case FPE_INTDIV:
 416         case FPE_FLTDIV:
 417             rt_error(uc, "division by zero");
 418             break;
 419         default:
 420             rt_error(uc, "floating point exception");
 421             break;
 422         }
 423         break;
 424     case SIGBUS:
 425     case SIGSEGV:
 426         if (rt_bound_error_msg && *rt_bound_error_msg)
 427             rt_error(uc, *rt_bound_error_msg);
 428         else
 429             rt_error(uc, "dereferencing invalid pointer");
 430         break;
 431     case SIGILL:
 432         rt_error(uc, "illegal instruction");
 433         break;
 434     case SIGABRT:
 435         rt_error(uc, "abort() called");
 436         break;
 437     default:
 438         rt_error(uc, "caught signal %d", signum);
 439         break;
 440     }
 441     exit(255);
 442 }
 443
 444 #ifndef SA_SIGINFO
 445 # define SA_SIGINFO 0x00000004u
 446 #endif
 447
 448 /* Generate a stack backtrace when a CPU exception occurs. */
 449 static void set_exception_handler(void)
 450 {
 451     struct sigaction sigact;
 452     /* install TCC signal handlers to print debug info on fatal
 453        runtime errors */
 454     sigact.sa_flags = SA_SIGINFO | SA_RESETHAND;
 455     sigact.sa_sigaction = sig_error;
 456     sigemptyset(&sigact.sa_mask);
 457     sigaction(SIGFPE, &sigact, NULL);
 458     sigaction(SIGILL, &sigact, NULL);
 459     sigaction(SIGSEGV, &sigact, NULL);
 460     sigaction(SIGBUS, &sigact, NULL);
 461     sigaction(SIGABRT, &sigact, NULL);
 462 }
 463
 464 /* ------------------------------------------------------------- */
 465 #ifdef __i386__
 466
 467 /* fix for glibc 2.1 */
 468 #ifndef REG_EIP
 469 #define REG_EIP EIP
 470 #define REG_EBP EBP
 471 #endif
 472
 473 /* return the PC at frame level 'level'. Return negative if not found */
 474 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
 475 {
 476     addr_t fp;
 477     int i;
 478
 479     if (level == 0) {
 480 #if defined(__APPLE__)
 481         *paddr = uc->uc_mcontext->__ss.__eip;
 482 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 483         *paddr = uc->uc_mcontext.mc_eip;
 484 #elif defined(__dietlibc__)
 485         *paddr = uc->uc_mcontext.eip;
 486 #else
 487         *paddr = uc->uc_mcontext.gregs[REG_EIP];
 488 #endif
 489         return 0;
 490     } else {
 491 #if defined(__APPLE__)
 492         fp = uc->uc_mcontext->__ss.__ebp;
 493 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 494         fp = uc->uc_mcontext.mc_ebp;
 495 #elif defined(__dietlibc__)
 496         fp = uc->uc_mcontext.ebp;
 497 #else
 498         fp = uc->uc_mcontext.gregs[REG_EBP];
 499 #endif
 500         for(i=1;i<level;i++) {
 501             /* XXX: check address validity with program info */
 502             if (fp <= 0x1000 || fp >= 0xc0000000)
 503                 return -1;
 504             fp = ((addr_t *)fp)[0];
 505         }
 506         *paddr = ((addr_t *)fp)[1];
 507         return 0;
 508     }
 509 }
 510
 511 /* ------------------------------------------------------------- */
 512 #elif defined(__x86_64__)
 513
 514 /* return the PC at frame level 'level'. Return negative if not found */
 515 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
 516 {
 517     addr_t fp;
 518     int i;
 519
 520     if (level == 0) {
 521         /* XXX: only support linux */
 522 #if defined(__APPLE__)
 523         *paddr = uc->uc_mcontext->__ss.__rip;
 524 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 525         *paddr = uc->uc_mcontext.mc_rip;
 526 #else
 527         *paddr = uc->uc_mcontext.gregs[REG_RIP];
 528 #endif
 529         return 0;
 530     } else {
 531 #if defined(__APPLE__)
 532         fp = uc->uc_mcontext->__ss.__rbp;
 533 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 534         fp = uc->uc_mcontext.mc_rbp;
 535 #else
 536         fp = uc->uc_mcontext.gregs[REG_RBP];
 537 #endif
 538         for(i=1;i<level;i++) {
 539             /* XXX: check address validity with program info */
 540             if (fp <= 0x1000)
 541                 return -1;
 542             fp = ((addr_t *)fp)[0];
 543         }
 544         *paddr = ((addr_t *)fp)[1];
 545         return 0;
 546     }
 547 }
 548
 549 /* ------------------------------------------------------------- */
 550 #elif defined(__arm__)
 551
 552 /* return the PC at frame level 'level'. Return negative if not found */
 553 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
 554 {
 555     addr_t fp, sp;
 556     int i;
 557
 558     if (level == 0) {
 559         /* XXX: only supports linux */
 560 #if defined(__linux__)
 561         *paddr = uc->uc_mcontext.arm_pc;
 562 #else
 563         return -1;
 564 #endif
 565         return 0;
 566     } else {
 567 #if defined(__linux__)
 568         fp = uc->uc_mcontext.arm_fp;
 569         sp = uc->uc_mcontext.arm_sp;
 570         if (sp < 0x1000)
 571             sp = 0x1000;
 572 #else
 573         return -1;
 574 #endif
 575         /* XXX: specific to tinycc stack frames */
 576         if (fp < sp + 12 || fp & 3)
 577             return -1;
 578         for(i = 1; i < level; i++) {
 579             sp = ((addr_t *)fp)[-2];
 580             if (sp < fp || sp - fp > 16 || sp & 3)
 581                 return -1;
 582             fp = ((addr_t *)fp)[-3];
 583             if (fp <= sp || fp - sp < 12 || fp & 3)
 584                 return -1;
 585         }
 586         /* XXX: check address validity with program info */
 587         *paddr = ((addr_t *)fp)[-1];
 588         return 0;
 589     }
 590 }
 591
 592 /* ------------------------------------------------------------- */
 593 #else
 594
 595 #warning add arch specific rt_get_caller_pc()
 596 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
 597 {
 598     return -1;
 599 }
 600
 601 #endif /* !__i386__ */
 602
 603 /* ------------------------------------------------------------- */
 604 #else /* WIN32 */
 605
 606 static long __stdcall cpu_exception_handler(EXCEPTION_POINTERS *ex_info)
 607 {
 608     EXCEPTION_RECORD *er = ex_info->ExceptionRecord;
 609     CONTEXT *uc = ex_info->ContextRecord;
 610     switch (er->ExceptionCode) {
 611     case EXCEPTION_ACCESS_VIOLATION:
 612         if (rt_bound_error_msg && *rt_bound_error_msg)
 613             rt_error(uc, *rt_bound_error_msg);
 614         else
 615             rt_error(uc, "access violation");
 616         break;
 617     case EXCEPTION_STACK_OVERFLOW:
 618         rt_error(uc, "stack overflow");
 619         break;
 620     case EXCEPTION_INT_DIVIDE_BY_ZERO:
 621         rt_error(uc, "division by zero");
 622         break;
 623     default:
 624         rt_error(uc, "exception caught");
 625         break;
 626     }
 627     return EXCEPTION_EXECUTE_HANDLER;
 628 }
 629
 630 /* Generate a stack backtrace when a CPU exception occurs. */
 631 static void set_exception_handler(void)
 632 {
 633     SetUnhandledExceptionFilter(cpu_exception_handler);
 634 }
 635
 636 #ifdef _WIN64
 637 static void win64_add_function_table(TCCState *s1)
 638 {
 639     RtlAddFunctionTable(
 640         (RUNTIME_FUNCTION*)s1->uw_pdata->sh_addr,
 641         s1->uw_pdata->data_offset / sizeof (RUNTIME_FUNCTION),
 642         text_section->sh_addr
 643         );
 644 }
 645 #endif
 646
 647 /* return the PC at frame level 'level'. Return non zero if not found */
 648 static int rt_get_caller_pc(addr_t *paddr, CONTEXT *uc, int level)
 649 {
 650     addr_t fp, pc;
 651     int i;
 652 #ifdef _WIN64
 653     pc = uc->Rip;
 654     fp = uc->Rbp;
 655 #else
 656     pc = uc->Eip;
 657     fp = uc->Ebp;
 658 #endif
 659     if (level > 0) {
 660         for(i=1;i<level;i++) {
 661             /* XXX: check address validity with program info */
 662             if (fp <= 0x1000 || fp >= 0xc0000000)
 663                 return -1;
 664             fp = ((addr_t*)fp)[0];
 665         }
 666         pc = ((addr_t*)fp)[1];
 667     }
 668     *paddr = pc;
 669     return 0;
 670 }
 671
 672 #endif /* _WIN32 */
 673 #endif /* CONFIG_TCC_BACKTRACE */
 674 /* ------------------------------------------------------------- */
 675 #ifdef CONFIG_TCC_STATIC
 676
 677 /* dummy function for profiling */
 678 ST_FUNC void *dlopen(const char *filename, int flag)
 679 {
 680     return NULL;
 681 }
 682
 683 ST_FUNC void dlclose(void *p)
 684 {
 685 }
 686
 687 ST_FUNC const char *dlerror(void)
 688 {
 689     return "error";
 690 }
 691
 692 typedef struct TCCSyms {
 693     char *str;
 694     void *ptr;
 695 } TCCSyms;
 696
 697
 698 /* add the symbol you want here if no dynamic linking is done */
 699 static TCCSyms tcc_syms[] = {
 700 #if !defined(CONFIG_TCCBOOT)
 701 #define TCCSYM(a) { #a, &a, },
 702     TCCSYM(printf)
 703     TCCSYM(fprintf)
 704     TCCSYM(fopen)
 705     TCCSYM(fclose)
 706 #undef TCCSYM
 707 #endif
 708     { NULL, NULL },
 709 };
 710
 711 ST_FUNC void *resolve_sym(TCCState *s1, const char *symbol)
 712 {
 713     TCCSyms *p;
 714     p = tcc_syms;
 715     while (p->str != NULL) {
 716         if (!strcmp(p->str, symbol))
 717             return p->ptr;
 718         p++;
 719     }
 720     return NULL;
 721 }
 722
 723 #elif !defined(_WIN32)
 724
 725 ST_FUNC void *resolve_sym(TCCState *s1, const char *sym)
 726 {
 727     return dlsym(RTLD_DEFAULT, sym);
 728 }
 729
 730 #endif /* CONFIG_TCC_STATIC */
 731 #endif /* TCC_IS_NATIVE */
 732 /* ------------------------------------------------------------- */