2 * TCC - Tiny C Compiler - Support for -run switch
4 * Copyright (c) 2001-2004 Fabrice Bellard
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.
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.
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
23 /* only native compiler supports -run */
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;
33 #define ucontext_t CONTEXT
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);
43 static void win64_add_function_table(TCCState *s1);
46 /* ------------------------------------------------------------- */
47 /* Do all relocations (needed before using tcc_get_symbol())
48 Returns -1 on error. */
50 LIBTCCAPI int tcc_relocate(TCCState *s1, void *ptr)
54 if (TCC_RELOCATE_AUTO != ptr)
55 return tcc_relocate_ex(s1, ptr);
57 ret = tcc_relocate_ex(s1, NULL);
62 { /* Use mmap instead of malloc for Selinux. Ref:
63 http://www.gnu.org/s/libc/manual/html_node/File-Size.html */
65 char tmpfname[] = "/tmp/.tccrunXXXXXX";
66 int fd = mkstemp (tmpfname);
70 ftruncate (fd, s1->mem_size);
72 s1->write_mem = mmap (NULL, ret, PROT_READ|PROT_WRITE,
74 if (s1->write_mem == MAP_FAILED)
75 tcc_error("/tmp not writeable");
77 s1->runtime_mem = mmap (NULL, ret, PROT_READ|PROT_EXEC,
79 if (s1->runtime_mem == MAP_FAILED)
80 tcc_error("/tmp not executable");
82 ret = tcc_relocate_ex(s1, s1->write_mem);
85 s1->runtime_mem = tcc_malloc(ret);
86 ret = tcc_relocate_ex(s1, s1->runtime_mem);
91 /* launch the compiled program with the given arguments */
92 LIBTCCAPI int tcc_run(TCCState *s1, int argc, char **argv)
94 int (*prog_main)(int, char **);
97 if (tcc_relocate(s1, TCC_RELOCATE_AUTO) < 0)
100 prog_main = tcc_get_symbol_err(s1, "main");
102 #ifdef CONFIG_TCC_BACKTRACE
104 set_exception_handler();
105 rt_prog_main = prog_main;
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");
119 ret = (*prog_main)(argc, argv);
123 ret = (*prog_main)(argc, argv);
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)
132 unsigned long offset, length;
139 pe_output_file(s1, NULL);
142 relocate_common_syms();
143 tcc_add_linker_symbols(s1);
144 build_got_entries(s1);
150 offset = 0, mem = (addr_t)ptr;
151 for(i = 1; i < s1->nb_sections; i++) {
153 if (0 == (s->sh_flags & SHF_ALLOC))
155 length = s->data_offset;
156 s->sh_addr = mem ? (mem + offset + 15) & ~15 : 0;
157 offset = (offset + length + 15) & ~15;
161 /* relocate symbols */
162 relocate_syms(s1, 1);
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? */
177 /* relocate each section */
178 for(i = 1; i < s1->nb_sections; i++) {
181 relocate_section(s1, s);
184 for(i = 1; i < s1->nb_sections; i++) {
186 if (0 == (s->sh_flags & SHF_ALLOC))
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);
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);
200 #ifdef TCC_HAS_RUNTIME_PLTGOT
201 set_pages_executable(s1->runtime_plt_and_got,
202 s1->runtime_plt_and_got_offset);
206 win64_add_function_table(s1);
211 /* ------------------------------------------------------------- */
212 /* allow to run code in memory */
214 static void set_pages_executable(void *ptr, unsigned long length)
217 unsigned long old_protect;
218 VirtualProtect(ptr, length, PAGE_EXECUTE_READWRITE, &old_protect);
221 # define PAGESIZE 4096
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 __clear_cache(ptr, ptr + length);
232 /* ------------------------------------------------------------- */
233 #ifdef CONFIG_TCC_BACKTRACE
235 ST_FUNC void tcc_set_num_callers(int n)
240 /* print the position in the source file of PC value 'pc' by reading
241 the stabs debug information */
242 static addr_t rt_printline(addr_t wanted_pc, const char *msg)
244 char func_name[128], last_func_name[128];
245 addr_t func_addr, last_pc, pc;
246 const char *incl_files[INCLUDE_STACK_SIZE];
247 int incl_index, len, last_line_num, i;
250 Stab_Sym *stab_sym = NULL, *stab_sym_end, *sym;
252 char *stab_str = NULL;
255 stab_len = stab_section->data_offset;
256 stab_sym = (Stab_Sym *)stab_section->data;
257 stab_str = stabstr_section->data;
263 last_func_name[0] = '\0';
264 last_pc = (addr_t)-1;
270 stab_sym_end = (Stab_Sym*)((char*)stab_sym + stab_len);
271 for (sym = stab_sym + 1; sym < stab_sym_end; ++sym) {
272 switch(sym->n_type) {
273 /* function start or end */
275 if (sym->n_strx == 0) {
276 /* we test if between last line and end of function */
277 pc = sym->n_value + func_addr;
278 if (wanted_pc >= last_pc && wanted_pc < pc)
283 str = stab_str + sym->n_strx;
284 p = strchr(str, ':');
286 pstrcpy(func_name, sizeof(func_name), str);
289 if (len > sizeof(func_name) - 1)
290 len = sizeof(func_name) - 1;
291 memcpy(func_name, str, len);
292 func_name[len] = '\0';
294 func_addr = sym->n_value;
297 /* line number info */
299 pc = sym->n_value + func_addr;
300 if (wanted_pc >= last_pc && wanted_pc < pc)
303 last_line_num = sym->n_desc;
305 strcpy(last_func_name, func_name);
309 str = stab_str + sym->n_strx;
311 if (incl_index < INCLUDE_STACK_SIZE) {
312 incl_files[incl_index++] = str;
320 if (sym->n_strx == 0) {
321 incl_index = 0; /* end of translation unit */
323 str = stab_str + sym->n_strx;
324 /* do not add path */
326 if (len > 0 && str[len - 1] != '/')
334 /* second pass: we try symtab symbols (no line number info) */
338 ElfW(Sym) *sym, *sym_end;
341 sym_end = (ElfW(Sym) *)(symtab_section->data + symtab_section->data_offset);
342 for(sym = (ElfW(Sym) *)symtab_section->data + 1;
345 type = ELFW(ST_TYPE)(sym->st_info);
346 if (type == STT_FUNC || type == STT_GNU_IFUNC) {
347 if (wanted_pc >= sym->st_value &&
348 wanted_pc < sym->st_value + sym->st_size) {
349 pstrcpy(last_func_name, sizeof(last_func_name),
350 strtab_section->data + sym->st_name);
351 func_addr = sym->st_value;
357 /* did not find any info: */
358 fprintf(stderr, "%s %p ???\n", msg, (void*)wanted_pc);
364 fprintf(stderr, "%s:%d: ", incl_files[--i], last_line_num);
365 fprintf(stderr, "%s %p", msg, (void*)wanted_pc);
366 if (last_func_name[0] != '\0')
367 fprintf(stderr, " %s()", last_func_name);
369 fprintf(stderr, " (included from ");
371 fprintf(stderr, "%s", incl_files[i]);
374 fprintf(stderr, ", ");
376 fprintf(stderr, ")");
378 fprintf(stderr, "\n");
383 /* emit a run time error at position 'pc' */
384 static void rt_error(ucontext_t *uc, const char *fmt, ...)
390 fprintf(stderr, "Runtime error: ");
392 vfprintf(stderr, fmt, ap);
394 fprintf(stderr, "\n");
396 for(i=0;i<rt_num_callers;i++) {
397 if (rt_get_caller_pc(&pc, uc, i) < 0)
399 pc = rt_printline(pc, i ? "by" : "at");
400 if (pc == (addr_t)rt_prog_main && pc)
405 /* ------------------------------------------------------------- */
408 /* signal handler for fatal errors */
409 static void sig_error(int signum, siginfo_t *siginf, void *puc)
411 ucontext_t *uc = puc;
415 switch(siginf->si_code) {
418 rt_error(uc, "division by zero");
421 rt_error(uc, "floating point exception");
427 if (rt_bound_error_msg && *rt_bound_error_msg)
428 rt_error(uc, *rt_bound_error_msg);
430 rt_error(uc, "dereferencing invalid pointer");
433 rt_error(uc, "illegal instruction");
436 rt_error(uc, "abort() called");
439 rt_error(uc, "caught signal %d", signum);
446 # define SA_SIGINFO 0x00000004u
449 /* Generate a stack backtrace when a CPU exception occurs. */
450 static void set_exception_handler(void)
452 struct sigaction sigact;
453 /* install TCC signal handlers to print debug info on fatal
455 sigact.sa_flags = SA_SIGINFO | SA_RESETHAND;
456 sigact.sa_sigaction = sig_error;
457 sigemptyset(&sigact.sa_mask);
458 sigaction(SIGFPE, &sigact, NULL);
459 sigaction(SIGILL, &sigact, NULL);
460 sigaction(SIGSEGV, &sigact, NULL);
461 sigaction(SIGBUS, &sigact, NULL);
462 sigaction(SIGABRT, &sigact, NULL);
465 /* ------------------------------------------------------------- */
468 /* fix for glibc 2.1 */
474 /* return the PC at frame level 'level'. Return negative if not found */
475 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
481 #if defined(__APPLE__)
482 *paddr = uc->uc_mcontext->__ss.__eip;
483 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
484 *paddr = uc->uc_mcontext.mc_eip;
485 #elif defined(__dietlibc__)
486 *paddr = uc->uc_mcontext.eip;
488 *paddr = uc->uc_mcontext.gregs[REG_EIP];
492 #if defined(__APPLE__)
493 fp = uc->uc_mcontext->__ss.__ebp;
494 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
495 fp = uc->uc_mcontext.mc_ebp;
496 #elif defined(__dietlibc__)
497 fp = uc->uc_mcontext.ebp;
499 fp = uc->uc_mcontext.gregs[REG_EBP];
501 for(i=1;i<level;i++) {
502 /* XXX: check address validity with program info */
503 if (fp <= 0x1000 || fp >= 0xc0000000)
505 fp = ((addr_t *)fp)[0];
507 *paddr = ((addr_t *)fp)[1];
512 /* ------------------------------------------------------------- */
513 #elif defined(__x86_64__)
515 /* return the PC at frame level 'level'. Return negative if not found */
516 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
522 /* XXX: only support linux */
523 #if defined(__APPLE__)
524 *paddr = uc->uc_mcontext->__ss.__rip;
525 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
526 *paddr = uc->uc_mcontext.mc_rip;
528 *paddr = uc->uc_mcontext.gregs[REG_RIP];
532 #if defined(__APPLE__)
533 fp = uc->uc_mcontext->__ss.__rbp;
534 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
535 fp = uc->uc_mcontext.mc_rbp;
537 fp = uc->uc_mcontext.gregs[REG_RBP];
539 for(i=1;i<level;i++) {
540 /* XXX: check address validity with program info */
543 fp = ((addr_t *)fp)[0];
545 *paddr = ((addr_t *)fp)[1];
550 /* ------------------------------------------------------------- */
551 #elif defined(__arm__)
553 /* return the PC at frame level 'level'. Return negative if not found */
554 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
560 /* XXX: only supports linux */
561 #if defined(__linux__)
562 *paddr = uc->uc_mcontext.arm_pc;
568 #if defined(__linux__)
569 fp = uc->uc_mcontext.arm_fp;
570 sp = uc->uc_mcontext.arm_sp;
576 /* XXX: specific to tinycc stack frames */
577 if (fp < sp + 12 || fp & 3)
579 for(i = 1; i < level; i++) {
580 sp = ((addr_t *)fp)[-2];
581 if (sp < fp || sp - fp > 16 || sp & 3)
583 fp = ((addr_t *)fp)[-3];
584 if (fp <= sp || fp - sp < 12 || fp & 3)
587 /* XXX: check address validity with program info */
588 *paddr = ((addr_t *)fp)[-1];
593 /* ------------------------------------------------------------- */
596 #warning add arch specific rt_get_caller_pc()
597 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
602 #endif /* !__i386__ */
604 /* ------------------------------------------------------------- */
607 static long __stdcall cpu_exception_handler(EXCEPTION_POINTERS *ex_info)
609 EXCEPTION_RECORD *er = ex_info->ExceptionRecord;
610 CONTEXT *uc = ex_info->ContextRecord;
611 switch (er->ExceptionCode) {
612 case EXCEPTION_ACCESS_VIOLATION:
613 if (rt_bound_error_msg && *rt_bound_error_msg)
614 rt_error(uc, *rt_bound_error_msg);
616 rt_error(uc, "access violation");
618 case EXCEPTION_STACK_OVERFLOW:
619 rt_error(uc, "stack overflow");
621 case EXCEPTION_INT_DIVIDE_BY_ZERO:
622 rt_error(uc, "division by zero");
625 rt_error(uc, "exception caught");
628 return EXCEPTION_EXECUTE_HANDLER;
631 /* Generate a stack backtrace when a CPU exception occurs. */
632 static void set_exception_handler(void)
634 SetUnhandledExceptionFilter(cpu_exception_handler);
638 static void win64_add_function_table(TCCState *s1)
641 (RUNTIME_FUNCTION*)s1->uw_pdata->sh_addr,
642 s1->uw_pdata->data_offset / sizeof (RUNTIME_FUNCTION),
643 text_section->sh_addr
648 /* return the PC at frame level 'level'. Return non zero if not found */
649 static int rt_get_caller_pc(addr_t *paddr, CONTEXT *uc, int level)
661 for(i=1;i<level;i++) {
662 /* XXX: check address validity with program info */
663 if (fp <= 0x1000 || fp >= 0xc0000000)
665 fp = ((addr_t*)fp)[0];
667 pc = ((addr_t*)fp)[1];
674 #endif /* CONFIG_TCC_BACKTRACE */
675 /* ------------------------------------------------------------- */
676 #ifdef CONFIG_TCC_STATIC
678 /* dummy function for profiling */
679 ST_FUNC void *dlopen(const char *filename, int flag)
684 ST_FUNC void dlclose(void *p)
688 ST_FUNC const char *dlerror(void)
693 typedef struct TCCSyms {
699 /* add the symbol you want here if no dynamic linking is done */
700 static TCCSyms tcc_syms[] = {
701 #if !defined(CONFIG_TCCBOOT)
702 #define TCCSYM(a) { #a, &a, },
712 ST_FUNC void *resolve_sym(TCCState *s1, const char *symbol)
716 while (p->str != NULL) {
717 if (!strcmp(p->str, symbol))
724 #elif !defined(_WIN32)
726 ST_FUNC void *resolve_sym(TCCState *s1, const char *sym)
728 return dlsym(RTLD_DEFAULT, sym);
731 #endif /* CONFIG_TCC_STATIC */
732 #endif /* TCC_IS_NATIVE */
733 /* ------------------------------------------------------------- */