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x86-64 bug fix: Fix stab generation for x86-64.
[tinycc.git] / tccelf.c
blob12ec736bf56657fad99a1122cd58a35b716c10cf
1 /*
2 * ELF file handling for TCC
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 #ifdef TCC_TARGET_X86_64
22 #define ElfW_Rel ElfW(Rela)
23 #define SHT_RELX SHT_RELA
24 #define REL_SECTION_FMT ".rela%s"
25 /* x86-64 requires PLT for DLLs */
26 #define TCC_OUTPUT_DLL_WITH_PLT
27 #else
28 #define ElfW_Rel ElfW(Rel)
29 #define SHT_RELX SHT_REL
30 #define REL_SECTION_FMT ".rel%s"
31 #endif
32
33 /* XXX: DLL with PLT would only work with x86-64 for now */
34 //#define TCC_OUTPUT_DLL_WITH_PLT
35
36 static int put_elf_str(Section *s, const char *sym)
37 {
38 int offset, len;
39 char *ptr;
40
41 len = strlen(sym) + 1;
42 offset = s->data_offset;
43 ptr = section_ptr_add(s, len);
44 memcpy(ptr, sym, len);
45 return offset;
46 }
47
48 /* elf symbol hashing function */
49 static unsigned long elf_hash(const unsigned char *name)
50 {
51 unsigned long h = 0, g;
52
53 while (*name) {
54 h = (h << 4) + *name++;
55 g = h & 0xf0000000;
56 if (g)
57 h ^= g >> 24;
58 h &= ~g;
59 }
60 return h;
61 }
62
63 /* rebuild hash table of section s */
64 /* NOTE: we do factorize the hash table code to go faster */
65 static void rebuild_hash(Section *s, unsigned int nb_buckets)
66 {
67 ElfW(Sym) *sym;
68 int *ptr, *hash, nb_syms, sym_index, h;
69 char *strtab;
70
71 strtab = s->link->data;
72 nb_syms = s->data_offset / sizeof(ElfW(Sym));
73
74 s->hash->data_offset = 0;
75 ptr = section_ptr_add(s->hash, (2 + nb_buckets + nb_syms) * sizeof(int));
76 ptr[0] = nb_buckets;
77 ptr[1] = nb_syms;
78 ptr += 2;
79 hash = ptr;
80 memset(hash, 0, (nb_buckets + 1) * sizeof(int));
81 ptr += nb_buckets + 1;
82
83 sym = (ElfW(Sym) *)s->data + 1;
84 for(sym_index = 1; sym_index < nb_syms; sym_index++) {
85 if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
86 h = elf_hash(strtab + sym->st_name) % nb_buckets;
87 *ptr = hash[h];
88 hash[h] = sym_index;
89 } else {
90 *ptr = 0;
91 }
92 ptr++;
93 sym++;
94 }
95 }
96
97 /* return the symbol number */
98 static int put_elf_sym(Section *s,
99 unsigned long value, unsigned long size,
100 int info, int other, int shndx, const char *name)
101 {
102 int name_offset, sym_index;
103 int nbuckets, h;
104 ElfW(Sym) *sym;
105 Section *hs;
106
107 sym = section_ptr_add(s, sizeof(ElfW(Sym)));
108 if (name)
109 name_offset = put_elf_str(s->link, name);
110 else
111 name_offset = 0;
112 /* XXX: endianness */
113 sym->st_name = name_offset;
114 sym->st_value = value;
115 sym->st_size = size;
116 sym->st_info = info;
117 sym->st_other = other;
118 sym->st_shndx = shndx;
119 sym_index = sym - (ElfW(Sym) *)s->data;
120 hs = s->hash;
121 if (hs) {
122 int *ptr, *base;
123 ptr = section_ptr_add(hs, sizeof(int));
124 base = (int *)hs->data;
125 /* only add global or weak symbols */
126 if (ELFW(ST_BIND)(info) != STB_LOCAL) {
127 /* add another hashing entry */
128 nbuckets = base[0];
129 h = elf_hash(name) % nbuckets;
130 *ptr = base[2 + h];
131 base[2 + h] = sym_index;
132 base[1]++;
133 /* we resize the hash table */
134 hs->nb_hashed_syms++;
135 if (hs->nb_hashed_syms > 2 * nbuckets) {
136 rebuild_hash(s, 2 * nbuckets);
137 }
138 } else {
139 *ptr = 0;
140 base[1]++;
141 }
142 }
143 return sym_index;
144 }
145
146 /* find global ELF symbol 'name' and return its index. Return 0 if not
147 found. */
148 static int find_elf_sym(Section *s, const char *name)
149 {
150 ElfW(Sym) *sym;
151 Section *hs;
152 int nbuckets, sym_index, h;
153 const char *name1;
154
155 hs = s->hash;
156 if (!hs)
157 return 0;
158 nbuckets = ((int *)hs->data)[0];
159 h = elf_hash(name) % nbuckets;
160 sym_index = ((int *)hs->data)[2 + h];
161 while (sym_index != 0) {
162 sym = &((ElfW(Sym) *)s->data)[sym_index];
163 name1 = s->link->data + sym->st_name;
164 if (!strcmp(name, name1))
165 return sym_index;
166 sym_index = ((int *)hs->data)[2 + nbuckets + sym_index];
167 }
168 return 0;
169 }
170
171 /* return elf symbol value or error */
172 int tcc_get_symbol(TCCState *s, unsigned long *pval, const char *name)
173 {
174 int sym_index;
175 ElfW(Sym) *sym;
176
177 sym_index = find_elf_sym(symtab_section, name);
178 if (!sym_index)
179 return -1;
180 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
181 *pval = sym->st_value;
182 return 0;
183 }
184
185 void *tcc_get_symbol_err(TCCState *s, const char *name)
186 {
187 unsigned long val;
188 if (tcc_get_symbol(s, &val, name) < 0)
189 error("%s not defined", name);
190 return (void *)val;
191 }
192
193 /* add an elf symbol : check if it is already defined and patch
194 it. Return symbol index. NOTE that sh_num can be SHN_UNDEF. */
195 static int add_elf_sym(Section *s, unsigned long value, unsigned long size,
196 int info, int other, int sh_num, const char *name)
197 {
198 ElfW(Sym) *esym;
199 int sym_bind, sym_index, sym_type, esym_bind;
200 unsigned char sym_vis, esym_vis, new_vis;
201
202 sym_bind = ELFW(ST_BIND)(info);
203 sym_type = ELFW(ST_TYPE)(info);
204 sym_vis = ELFW(ST_VISIBILITY)(other);
205
206 if (sym_bind != STB_LOCAL) {
207 /* we search global or weak symbols */
208 sym_index = find_elf_sym(s, name);
209 if (!sym_index)
210 goto do_def;
211 esym = &((ElfW(Sym) *)s->data)[sym_index];
212 if (esym->st_shndx != SHN_UNDEF) {
213 esym_bind = ELFW(ST_BIND)(esym->st_info);
214 /* propagate the most constraining visibility */
215 /* STV_DEFAULT(0)<STV_PROTECTED(3)<STV_HIDDEN(2)<STV_INTERNAL(1) */
216 esym_vis = ELFW(ST_VISIBILITY)(esym->st_other);
217 if (esym_vis == STV_DEFAULT) {
218 new_vis = sym_vis;
219 } else if (sym_vis == STV_DEFAULT) {
220 new_vis = esym_vis;
221 } else {
222 new_vis = (esym_vis < sym_vis) ? esym_vis : sym_vis;
223 }
224 esym->st_other = (esym->st_other & ~ELFW(ST_VISIBILITY)(-1))
225 | new_vis;
226 other = esym->st_other; /* in case we have to patch esym */
227 if (sh_num == SHN_UNDEF) {
228 /* ignore adding of undefined symbol if the
229 corresponding symbol is already defined */
230 } else if (sym_bind == STB_GLOBAL && esym_bind == STB_WEAK) {
231 /* global overrides weak, so patch */
232 goto do_patch;
233 } else if (sym_bind == STB_WEAK && esym_bind == STB_GLOBAL) {
234 /* weak is ignored if already global */
235 } else if (sym_vis == STV_HIDDEN || sym_vis == STV_INTERNAL) {
236 /* ignore hidden symbols after */
237 } else if (esym->st_shndx == SHN_COMMON && sh_num < SHN_LORESERVE) {
238 /* gr: Happens with 'tcc ... -static tcctest.c' on e.g. Ubuntu 6.01
239 No idea if this is the correct solution ... */
240 goto do_patch;
241 } else if (s == tcc_state->dynsymtab_section) {
242 /* we accept that two DLL define the same symbol */
243 } else {
244 #if 1
245 printf("new_bind=%x new_shndx=%x new_vis=%x old_bind=%x old_shndx=%x old_vis=%x\n",
246 sym_bind, sh_num, new_vis, esym_bind, esym->st_shndx, esym_vis);
247 #endif
248 error_noabort("'%s' defined twice", name);
249 }
250 } else {
251 do_patch:
252 esym->st_info = ELFW(ST_INFO)(sym_bind, sym_type);
253 esym->st_shndx = sh_num;
254 esym->st_value = value;
255 esym->st_size = size;
256 esym->st_other = other;
257 }
258 } else {
259 do_def:
260 sym_index = put_elf_sym(s, value, size,
261 ELFW(ST_INFO)(sym_bind, sym_type), other,
262 sh_num, name);
263 }
264 return sym_index;
265 }
266
267 /* put relocation */
268 static void put_elf_reloc(Section *symtab, Section *s, unsigned long offset,
269 int type, int symbol)
270 {
271 char buf[256];
272 Section *sr;
273 ElfW_Rel *rel;
274
275 sr = s->reloc;
276 if (!sr) {
277 /* if no relocation section, create it */
278 snprintf(buf, sizeof(buf), REL_SECTION_FMT, s->name);
279 /* if the symtab is allocated, then we consider the relocation
280 are also */
281 sr = new_section(tcc_state, buf, SHT_RELX, symtab->sh_flags);
282 sr->sh_entsize = sizeof(ElfW_Rel);
283 sr->link = symtab;
284 sr->sh_info = s->sh_num;
285 s->reloc = sr;
286 }
287 rel = section_ptr_add(sr, sizeof(ElfW_Rel));
288 rel->r_offset = offset;
289 rel->r_info = ELFW(R_INFO)(symbol, type);
290 #ifdef TCC_TARGET_X86_64
291 rel->r_addend = 0;
292 #endif
293 }
294
295 /* put stab debug information */
296
297 typedef struct {
298 unsigned int n_strx; /* index into string table of name */
299 unsigned char n_type; /* type of symbol */
300 unsigned char n_other; /* misc info (usually empty) */
301 unsigned short n_desc; /* description field */
302 unsigned int n_value; /* value of symbol */
303 } Stab_Sym;
304
305 static void put_stabs(const char *str, int type, int other, int desc,
306 unsigned long value)
307 {
308 Stab_Sym *sym;
309
310 sym = section_ptr_add(stab_section, sizeof(Stab_Sym));
311 if (str) {
312 sym->n_strx = put_elf_str(stabstr_section, str);
313 } else {
314 sym->n_strx = 0;
315 }
316 sym->n_type = type;
317 sym->n_other = other;
318 sym->n_desc = desc;
319 sym->n_value = value;
320 }
321
322 static void put_stabs_r(const char *str, int type, int other, int desc,
323 unsigned long value, Section *sec, int sym_index)
324 {
325 put_stabs(str, type, other, desc, value);
326 put_elf_reloc(symtab_section, stab_section,
327 stab_section->data_offset - sizeof(unsigned int),
328 R_DATA_32, sym_index);
329 }
330
331 static void put_stabn(int type, int other, int desc, int value)
332 {
333 put_stabs(NULL, type, other, desc, value);
334 }
335
336 static void put_stabd(int type, int other, int desc)
337 {
338 put_stabs(NULL, type, other, desc, 0);
339 }
340
341 /* In an ELF file symbol table, the local symbols must appear below
342 the global and weak ones. Since TCC cannot sort it while generating
343 the code, we must do it after. All the relocation tables are also
344 modified to take into account the symbol table sorting */
345 static void sort_syms(TCCState *s1, Section *s)
346 {
347 int *old_to_new_syms;
348 ElfW(Sym) *new_syms;
349 int nb_syms, i;
350 ElfW(Sym) *p, *q;
351 ElfW_Rel *rel, *rel_end;
352 Section *sr;
353 int type, sym_index;
354
355 nb_syms = s->data_offset / sizeof(ElfW(Sym));
356 new_syms = tcc_malloc(nb_syms * sizeof(ElfW(Sym)));
357 old_to_new_syms = tcc_malloc(nb_syms * sizeof(int));
358
359 /* first pass for local symbols */
360 p = (ElfW(Sym) *)s->data;
361 q = new_syms;
362 for(i = 0; i < nb_syms; i++) {
363 if (ELFW(ST_BIND)(p->st_info) == STB_LOCAL) {
364 old_to_new_syms[i] = q - new_syms;
365 *q++ = *p;
366 }
367 p++;
368 }
369 /* save the number of local symbols in section header */
370 s->sh_info = q - new_syms;
371
372 /* then second pass for non local symbols */
373 p = (ElfW(Sym) *)s->data;
374 for(i = 0; i < nb_syms; i++) {
375 if (ELFW(ST_BIND)(p->st_info) != STB_LOCAL) {
376 old_to_new_syms[i] = q - new_syms;
377 *q++ = *p;
378 }
379 p++;
380 }
381
382 /* we copy the new symbols to the old */
383 memcpy(s->data, new_syms, nb_syms * sizeof(ElfW(Sym)));
384 tcc_free(new_syms);
385
386 /* now we modify all the relocations */
387 for(i = 1; i < s1->nb_sections; i++) {
388 sr = s1->sections[i];
389 if (sr->sh_type == SHT_RELX && sr->link == s) {
390 rel_end = (ElfW_Rel *)(sr->data + sr->data_offset);
391 for(rel = (ElfW_Rel *)sr->data;
392 rel < rel_end;
393 rel++) {
394 sym_index = ELFW(R_SYM)(rel->r_info);
395 type = ELFW(R_TYPE)(rel->r_info);
396 sym_index = old_to_new_syms[sym_index];
397 rel->r_info = ELFW(R_INFO)(sym_index, type);
398 }
399 }
400 }
401
402 tcc_free(old_to_new_syms);
403 }
404
405 /* relocate common symbols in the .bss section */
406 static void relocate_common_syms(void)
407 {
408 ElfW(Sym) *sym, *sym_end;
409 unsigned long offset, align;
410
411 sym_end = (ElfW(Sym) *)(symtab_section->data + symtab_section->data_offset);
412 for(sym = (ElfW(Sym) *)symtab_section->data + 1;
413 sym < sym_end;
414 sym++) {
415 if (sym->st_shndx == SHN_COMMON) {
416 /* align symbol */
417 align = sym->st_value;
418 offset = bss_section->data_offset;
419 offset = (offset + align - 1) & -align;
420 sym->st_value = offset;
421 sym->st_shndx = bss_section->sh_num;
422 offset += sym->st_size;
423 bss_section->data_offset = offset;
424 }
425 }
426 }
427
428 /* relocate symbol table, resolve undefined symbols if do_resolve is
429 true and output error if undefined symbol. */
430 static void relocate_syms(TCCState *s1, int do_resolve)
431 {
432 ElfW(Sym) *sym, *esym, *sym_end;
433 int sym_bind, sh_num, sym_index;
434 const char *name;
435 unsigned long addr;
436
437 sym_end = (ElfW(Sym) *)(symtab_section->data + symtab_section->data_offset);
438 for(sym = (ElfW(Sym) *)symtab_section->data + 1;
439 sym < sym_end;
440 sym++) {
441 sh_num = sym->st_shndx;
442 if (sh_num == SHN_UNDEF) {
443 name = strtab_section->data + sym->st_name;
444 if (do_resolve) {
445 name = symtab_section->link->data + sym->st_name;
446 addr = (unsigned long)resolve_sym(s1, name, ELFW(ST_TYPE)(sym->st_info));
447 if (addr) {
448 sym->st_value = addr;
449 goto found;
450 }
451 } else if (s1->dynsym) {
452 /* if dynamic symbol exist, then use it */
453 sym_index = find_elf_sym(s1->dynsym, name);
454 if (sym_index) {
455 esym = &((ElfW(Sym) *)s1->dynsym->data)[sym_index];
456 sym->st_value = esym->st_value;
457 goto found;
458 }
459 }
460 /* XXX: _fp_hw seems to be part of the ABI, so we ignore
461 it */
462 if (!strcmp(name, "_fp_hw"))
463 goto found;
464 /* only weak symbols are accepted to be undefined. Their
465 value is zero */
466 sym_bind = ELFW(ST_BIND)(sym->st_info);
467 if (sym_bind == STB_WEAK) {
468 sym->st_value = 0;
469 } else {
470 error_noabort("undefined symbol '%s'", name);
471 }
472 } else if (sh_num < SHN_LORESERVE) {
473 /* add section base */
474 sym->st_value += s1->sections[sym->st_shndx]->sh_addr;
475 }
476 found: ;
477 }
478 }
479
480 #ifdef TCC_TARGET_X86_64
481 #define JMP_TABLE_ENTRY_SIZE 14
482 #define JMP_TABLE_ENTRY_MAX_NUM 4096
483 static unsigned long add_jmp_table(TCCState *s1, unsigned long val)
484 {
485 char *p;
486 if (!s1->jmp_table) {
487 int size = JMP_TABLE_ENTRY_SIZE * JMP_TABLE_ENTRY_MAX_NUM;
488 s1->jmp_table_num = 0;
489 s1->jmp_table = (char *)tcc_malloc(size);
490 set_pages_executable(s1->jmp_table, size);
491 }
492 if (s1->jmp_table_num == JMP_TABLE_ENTRY_MAX_NUM) {
493 error("relocating >%d symbols are not supported",
494 JMP_TABLE_ENTRY_MAX_NUM);
495 }
496 p = s1->jmp_table + s1->jmp_table_num * JMP_TABLE_ENTRY_SIZE;
497 s1->jmp_table_num++;
498 /* jmp *0x0(%rip) */
499 p[0] = 0xff;
500 p[1] = 0x25;
501 *(int *)(p + 2) = 0;
502 *(unsigned long *)(p + 6) = val;
503 return (unsigned long)p;
504 }
505 #endif
506
507 /* relocate a given section (CPU dependent) */
508 static void relocate_section(TCCState *s1, Section *s)
509 {
510 Section *sr;
511 ElfW_Rel *rel, *rel_end, *qrel;
512 ElfW(Sym) *sym;
513 int type, sym_index;
514 unsigned char *ptr;
515 unsigned long val, addr;
516 int esym_index;
517
518 sr = s->reloc;
519 rel_end = (ElfW_Rel *)(sr->data + sr->data_offset);
520 qrel = (ElfW_Rel *)sr->data;
521 for(rel = qrel;
522 rel < rel_end;
523 rel++) {
524 ptr = s->data + rel->r_offset;
525
526 sym_index = ELFW(R_SYM)(rel->r_info);
527 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
528 val = sym->st_value;
529 #ifdef TCC_TARGET_X86_64
530 /* XXX: not tested */
531 val += rel->r_addend;
532 #endif
533 type = ELFW(R_TYPE)(rel->r_info);
534 addr = s->sh_addr + rel->r_offset;
535
536 /* CPU specific */
537 switch(type) {
538 #if defined(TCC_TARGET_I386)
539 case R_386_32:
540 if (s1->output_type == TCC_OUTPUT_DLL) {
541 esym_index = s1->symtab_to_dynsym[sym_index];
542 qrel->r_offset = rel->r_offset;
543 if (esym_index) {
544 qrel->r_info = ELFW(R_INFO)(esym_index, R_386_32);
545 qrel++;
546 break;
547 } else {
548 qrel->r_info = ELFW(R_INFO)(0, R_386_RELATIVE);
549 qrel++;
550 }
551 }
552 *(int *)ptr += val;
553 break;
554 case R_386_PC32:
555 if (s1->output_type == TCC_OUTPUT_DLL) {
556 /* DLL relocation */
557 esym_index = s1->symtab_to_dynsym[sym_index];
558 if (esym_index) {
559 qrel->r_offset = rel->r_offset;
560 qrel->r_info = ELFW(R_INFO)(esym_index, R_386_PC32);
561 qrel++;
562 break;
563 }
564 }
565 *(int *)ptr += val - addr;
566 break;
567 case R_386_PLT32:
568 *(int *)ptr += val - addr;
569 break;
570 case R_386_GLOB_DAT:
571 case R_386_JMP_SLOT:
572 *(int *)ptr = val;
573 break;
574 case R_386_GOTPC:
575 *(int *)ptr += s1->got->sh_addr - addr;
576 break;
577 case R_386_GOTOFF:
578 *(int *)ptr += val - s1->got->sh_addr;
579 break;
580 case R_386_GOT32:
581 /* we load the got offset */
582 *(int *)ptr += s1->got_offsets[sym_index];
583 break;
584 #elif defined(TCC_TARGET_ARM)
585 case R_ARM_PC24:
586 case R_ARM_CALL:
587 case R_ARM_JUMP24:
588 case R_ARM_PLT32:
589 {
590 int x;
591 x = (*(int *)ptr)&0xffffff;
592 (*(int *)ptr) &= 0xff000000;
593 if (x & 0x800000)
594 x -= 0x1000000;
595 x *= 4;
596 x += val - addr;
597 if((x & 3) != 0 || x >= 0x4000000 || x < -0x4000000)
598 error("can't relocate value at %x",addr);
599 x >>= 2;
600 x &= 0xffffff;
601 (*(int *)ptr) |= x;
602 }
603 break;
604 case R_ARM_PREL31:
605 {
606 int x;
607 x = (*(int *)ptr) & 0x7fffffff;
608 (*(int *)ptr) &= 0x80000000;
609 x = (x * 2) / 2;
610 x += val - addr;
611 if((x^(x>>1))&0x40000000)
612 error("can't relocate value at %x",addr);
613 (*(int *)ptr) |= x & 0x7fffffff;
614 }
615 case R_ARM_ABS32:
616 *(int *)ptr += val;
617 break;
618 case R_ARM_BASE_PREL:
619 *(int *)ptr += s1->got->sh_addr - addr;
620 break;
621 case R_ARM_GOTOFF32:
622 *(int *)ptr += val - s1->got->sh_addr;
623 break;
624 case R_ARM_GOT_BREL:
625 /* we load the got offset */
626 *(int *)ptr += s1->got_offsets[sym_index];
627 break;
628 case R_ARM_COPY:
629 break;
630 default:
631 fprintf(stderr,"FIXME: handle reloc type %x at %lx [%.8x] to %lx\n",
632 type,addr,(unsigned int )ptr,val);
633 break;
634 #elif defined(TCC_TARGET_C67)
635 case R_C60_32:
636 *(int *)ptr += val;
637 break;
638 case R_C60LO16:
639 {
640 uint32_t orig;
641
642 /* put the low 16 bits of the absolute address */
643 // add to what is already there
644
645 orig = ((*(int *)(ptr )) >> 7) & 0xffff;
646 orig |= (((*(int *)(ptr+4)) >> 7) & 0xffff) << 16;
647
648 //patch both at once - assumes always in pairs Low - High
649
650 *(int *) ptr = (*(int *) ptr & (~(0xffff << 7)) ) | (((val+orig) & 0xffff) << 7);
651 *(int *)(ptr+4) = (*(int *)(ptr+4) & (~(0xffff << 7)) ) | ((((val+orig)>>16) & 0xffff) << 7);
652 }
653 break;
654 case R_C60HI16:
655 break;
656 default:
657 fprintf(stderr,"FIXME: handle reloc type %x at %lx [%.8x] to %lx\n",
658 type,addr,(unsigned int )ptr,val);
659 break;
660 #elif defined(TCC_TARGET_X86_64)
661 case R_X86_64_64:
662 if (s1->output_type == TCC_OUTPUT_DLL) {
663 qrel->r_info = ELFW(R_INFO)(0, R_X86_64_RELATIVE);
664 qrel->r_addend = *(long long *)ptr + val;
665 qrel++;
666 }
667 *(long long *)ptr += val;
668 break;
669 case R_X86_64_32:
670 case R_X86_64_32S:
671 if (s1->output_type == TCC_OUTPUT_DLL) {
672 /* XXX: this logic may depend on TCC's codegen
673 now TCC uses R_X86_64_32 even for a 64bit pointer */
674 qrel->r_info = ELFW(R_INFO)(0, R_X86_64_RELATIVE);
675 qrel->r_addend = *(int *)ptr + val;
676 qrel++;
677 }
678 *(int *)ptr += val;
679 break;
680 case R_X86_64_PC32: {
681 if (s1->output_type == TCC_OUTPUT_DLL) {
682 /* DLL relocation */
683 esym_index = s1->symtab_to_dynsym[sym_index];
684 if (esym_index) {
685 qrel->r_offset = rel->r_offset;
686 qrel->r_info = ELFW(R_INFO)(esym_index, R_X86_64_PC32);
687 qrel->r_addend = *(int *)ptr;
688 qrel++;
689 break;
690 }
691 }
692 long diff = val - addr;
693 if (diff < -2147483648 || diff > 2147483647) {
694 /* XXX: naive support for over 32bit jump */
695 if (s1->output_type == TCC_OUTPUT_MEMORY) {
696 val = add_jmp_table(s1, val);
697 diff = val - addr;
698 }
699 if (diff <= -2147483647 || diff > 2147483647) {
700 #if 0
701 /* output memory map to debug easily */
702 FILE* fp;
703 char buf[4096];
704 int size;
705 Dl_info di;
706 printf("%ld - %ld = %ld\n", val, addr, diff);
707 dladdr((void *)addr, &di);
708 printf("addr = %lx = %lx+%lx(%s) ptr=%p\n",
709 addr, s->sh_addr, rel->r_offset, di.dli_sname,
710 ptr);
711 fp = fopen("/proc/self/maps", "r");
712 size = fread(buf, 1, 4095, fp);
713 buf[size] = '\0';
714 printf("%s", buf);
715 #endif
716 error("internal error: relocation failed");
717 }
718 }
719 *(int *)ptr += diff;
720 }
721 break;
722 case R_X86_64_PLT32:
723 *(int *)ptr += val - addr;
724 break;
725 case R_X86_64_GLOB_DAT:
726 case R_X86_64_JUMP_SLOT:
727 *(int *)ptr = val;
728 break;
729 case R_X86_64_GOTPCREL:
730 *(int *)ptr += s1->got->sh_addr - addr;
731 break;
732 case R_X86_64_GOTTPOFF:
733 *(int *)ptr += val - s1->got->sh_addr;
734 break;
735 case R_X86_64_GOT32:
736 /* we load the got offset */
737 *(int *)ptr += s1->got_offsets[sym_index];
738 break;
739 #else
740 #error unsupported processor
741 #endif
742 }
743 }
744 /* if the relocation is allocated, we change its symbol table */
745 if (sr->sh_flags & SHF_ALLOC)
746 sr->link = s1->dynsym;
747 }
748
749 /* relocate relocation table in 'sr' */
750 static void relocate_rel(TCCState *s1, Section *sr)
751 {
752 Section *s;
753 ElfW_Rel *rel, *rel_end;
754
755 s = s1->sections[sr->sh_info];
756 rel_end = (ElfW_Rel *)(sr->data + sr->data_offset);
757 for(rel = (ElfW_Rel *)sr->data;
758 rel < rel_end;
759 rel++) {
760 rel->r_offset += s->sh_addr;
761 }
762 }
763
764 /* count the number of dynamic relocations so that we can reserve
765 their space */
766 static int prepare_dynamic_rel(TCCState *s1, Section *sr)
767 {
768 ElfW_Rel *rel, *rel_end;
769 int sym_index, esym_index, type, count;
770
771 count = 0;
772 rel_end = (ElfW_Rel *)(sr->data + sr->data_offset);
773 for(rel = (ElfW_Rel *)sr->data; rel < rel_end; rel++) {
774 sym_index = ELFW(R_SYM)(rel->r_info);
775 type = ELFW(R_TYPE)(rel->r_info);
776 switch(type) {
777 #if defined(TCC_TARGET_I386)
778 case R_386_32:
779 #elif defined(TCC_TARGET_X86_64)
780 case R_X86_64_32:
781 case R_X86_64_32S:
782 #endif
783 count++;
784 break;
785 #if defined(TCC_TARGET_I386)
786 case R_386_PC32:
787 #elif defined(TCC_TARGET_X86_64)
788 case R_X86_64_PC32:
789 #endif
790 esym_index = s1->symtab_to_dynsym[sym_index];
791 if (esym_index)
792 count++;
793 break;
794 default:
795 break;
796 }
797 }
798 if (count) {
799 /* allocate the section */
800 sr->sh_flags |= SHF_ALLOC;
801 sr->sh_size = count * sizeof(ElfW_Rel);
802 }
803 return count;
804 }
805
806 static void put_got_offset(TCCState *s1, int index, unsigned long val)
807 {
808 int n;
809 unsigned long *tab;
810
811 if (index >= s1->nb_got_offsets) {
812 /* find immediately bigger power of 2 and reallocate array */
813 n = 1;
814 while (index >= n)
815 n *= 2;
816 tab = tcc_realloc(s1->got_offsets, n * sizeof(unsigned long));
817 if (!tab)
818 error("memory full");
819 s1->got_offsets = tab;
820 memset(s1->got_offsets + s1->nb_got_offsets, 0,
821 (n - s1->nb_got_offsets) * sizeof(unsigned long));
822 s1->nb_got_offsets = n;
823 }
824 s1->got_offsets[index] = val;
825 }
826
827 /* XXX: suppress that */
828 static void put32(unsigned char *p, uint32_t val)
829 {
830 p[0] = val;
831 p[1] = val >> 8;
832 p[2] = val >> 16;
833 p[3] = val >> 24;
834 }
835
836 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_ARM) || \
837 defined(TCC_TARGET_X86_64)
838 static uint32_t get32(unsigned char *p)
839 {
840 return p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);
841 }
842 #endif
843
844 static void build_got(TCCState *s1)
845 {
846 unsigned char *ptr;
847
848 /* if no got, then create it */
849 s1->got = new_section(s1, ".got", SHT_PROGBITS, SHF_ALLOC | SHF_WRITE);
850 s1->got->sh_entsize = 4;
851 add_elf_sym(symtab_section, 0, 4, ELFW(ST_INFO)(STB_GLOBAL, STT_OBJECT),
852 0, s1->got->sh_num, "_GLOBAL_OFFSET_TABLE_");
853 ptr = section_ptr_add(s1->got, 3 * PTR_SIZE);
854 #if PTR_SIZE == 4
855 /* keep space for _DYNAMIC pointer, if present */
856 put32(ptr, 0);
857 /* two dummy got entries */
858 put32(ptr + 4, 0);
859 put32(ptr + 8, 0);
860 #else
861 /* keep space for _DYNAMIC pointer, if present */
862 put32(ptr, 0);
863 put32(ptr + 4, 0);
864 /* two dummy got entries */
865 put32(ptr + 8, 0);
866 put32(ptr + 12, 0);
867 put32(ptr + 16, 0);
868 put32(ptr + 20, 0);
869 #endif
870 }
871
872 /* put a got entry corresponding to a symbol in symtab_section. 'size'
873 and 'info' can be modifed if more precise info comes from the DLL */
874 static void put_got_entry(TCCState *s1,
875 int reloc_type, unsigned long size, int info,
876 int sym_index)
877 {
878 int index;
879 const char *name;
880 ElfW(Sym) *sym;
881 unsigned long offset;
882 int *ptr;
883
884 if (!s1->got)
885 build_got(s1);
886
887 /* if a got entry already exists for that symbol, no need to add one */
888 if (sym_index < s1->nb_got_offsets &&
889 s1->got_offsets[sym_index] != 0)
890 return;
891
892 put_got_offset(s1, sym_index, s1->got->data_offset);
893
894 if (s1->dynsym) {
895 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
896 name = symtab_section->link->data + sym->st_name;
897 offset = sym->st_value;
898 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
899 if (reloc_type ==
900 #ifdef TCC_TARGET_X86_64
901 R_X86_64_JUMP_SLOT
902 #else
903 R_386_JMP_SLOT
904 #endif
905 ) {
906 Section *plt;
907 uint8_t *p;
908 int modrm;
909
910 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
911 modrm = 0x25;
912 #else
913 /* if we build a DLL, we add a %ebx offset */
914 if (s1->output_type == TCC_OUTPUT_DLL)
915 modrm = 0xa3;
916 else
917 modrm = 0x25;
918 #endif
919
920 /* add a PLT entry */
921 plt = s1->plt;
922 if (plt->data_offset == 0) {
923 /* first plt entry */
924 p = section_ptr_add(plt, 16);
925 p[0] = 0xff; /* pushl got + PTR_SIZE */
926 p[1] = modrm + 0x10;
927 put32(p + 2, PTR_SIZE);
928 p[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */
929 p[7] = modrm;
930 put32(p + 8, PTR_SIZE * 2);
931 }
932
933 p = section_ptr_add(plt, 16);
934 p[0] = 0xff; /* jmp *(got + x) */
935 p[1] = modrm;
936 put32(p + 2, s1->got->data_offset);
937 p[6] = 0x68; /* push $xxx */
938 put32(p + 7, (plt->data_offset - 32) >> 1);
939 p[11] = 0xe9; /* jmp plt_start */
940 put32(p + 12, -(plt->data_offset));
941
942 /* the symbol is modified so that it will be relocated to
943 the PLT */
944 #if !defined(TCC_OUTPUT_DLL_WITH_PLT)
945 if (s1->output_type == TCC_OUTPUT_EXE)
946 #endif
947 offset = plt->data_offset - 16;
948 }
949 #elif defined(TCC_TARGET_ARM)
950 if (reloc_type == R_ARM_JUMP_SLOT) {
951 Section *plt;
952 uint8_t *p;
953
954 /* if we build a DLL, we add a %ebx offset */
955 if (s1->output_type == TCC_OUTPUT_DLL)
956 error("DLLs unimplemented!");
957
958 /* add a PLT entry */
959 plt = s1->plt;
960 if (plt->data_offset == 0) {
961 /* first plt entry */
962 p = section_ptr_add(plt, 16);
963 put32(p , 0xe52de004);
964 put32(p + 4, 0xe59fe010);
965 put32(p + 8, 0xe08fe00e);
966 put32(p + 12, 0xe5bef008);
967 }
968
969 p = section_ptr_add(plt, 16);
970 put32(p , 0xe59fc004);
971 put32(p+4, 0xe08fc00c);
972 put32(p+8, 0xe59cf000);
973 put32(p+12, s1->got->data_offset);
974
975 /* the symbol is modified so that it will be relocated to
976 the PLT */
977 if (s1->output_type == TCC_OUTPUT_EXE)
978 offset = plt->data_offset - 16;
979 }
980 #elif defined(TCC_TARGET_C67)
981 error("C67 got not implemented");
982 #else
983 #error unsupported CPU
984 #endif
985 index = put_elf_sym(s1->dynsym, offset,
986 size, info, 0, sym->st_shndx, name);
987 /* put a got entry */
988 put_elf_reloc(s1->dynsym, s1->got,
989 s1->got->data_offset,
990 reloc_type, index);
991 }
992 ptr = section_ptr_add(s1->got, PTR_SIZE);
993 *ptr = 0;
994 }
995
996 /* build GOT and PLT entries */
997 static void build_got_entries(TCCState *s1)
998 {
999 Section *s, *symtab;
1000 ElfW_Rel *rel, *rel_end;
1001 ElfW(Sym) *sym;
1002 int i, type, reloc_type, sym_index;
1003
1004 for(i = 1; i < s1->nb_sections; i++) {
1005 s = s1->sections[i];
1006 if (s->sh_type != SHT_RELX)
1007 continue;
1008 /* no need to handle got relocations */
1009 if (s->link != symtab_section)
1010 continue;
1011 symtab = s->link;
1012 rel_end = (ElfW_Rel *)(s->data + s->data_offset);
1013 for(rel = (ElfW_Rel *)s->data;
1014 rel < rel_end;
1015 rel++) {
1016 type = ELFW(R_TYPE)(rel->r_info);
1017 switch(type) {
1018 #if defined(TCC_TARGET_I386)
1019 case R_386_GOT32:
1020 case R_386_GOTOFF:
1021 case R_386_GOTPC:
1022 case R_386_PLT32:
1023 if (!s1->got)
1024 build_got(s1);
1025 if (type == R_386_GOT32 || type == R_386_PLT32) {
1026 sym_index = ELFW(R_SYM)(rel->r_info);
1027 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1028 /* look at the symbol got offset. If none, then add one */
1029 if (type == R_386_GOT32)
1030 reloc_type = R_386_GLOB_DAT;
1031 else
1032 reloc_type = R_386_JMP_SLOT;
1033 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1034 sym_index);
1035 }
1036 break;
1037 #elif defined(TCC_TARGET_ARM)
1038 case R_ARM_GOT_BREL:
1039 case R_ARM_GOTOFF32:
1040 case R_ARM_BASE_PREL:
1041 case R_ARM_PLT32:
1042 if (!s1->got)
1043 build_got(s1);
1044 if (type == R_ARM_GOT_BREL || type == R_ARM_PLT32) {
1045 sym_index = ELFW(R_SYM)(rel->r_info);
1046 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1047 /* look at the symbol got offset. If none, then add one */
1048 if (type == R_ARM_GOT_BREL)
1049 reloc_type = R_ARM_GLOB_DAT;
1050 else
1051 reloc_type = R_ARM_JUMP_SLOT;
1052 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1053 sym_index);
1054 }
1055 break;
1056 #elif defined(TCC_TARGET_C67)
1057 case R_C60_GOT32:
1058 case R_C60_GOTOFF:
1059 case R_C60_GOTPC:
1060 case R_C60_PLT32:
1061 if (!s1->got)
1062 build_got(s1);
1063 if (type == R_C60_GOT32 || type == R_C60_PLT32) {
1064 sym_index = ELFW(R_SYM)(rel->r_info);
1065 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1066 /* look at the symbol got offset. If none, then add one */
1067 if (type == R_C60_GOT32)
1068 reloc_type = R_C60_GLOB_DAT;
1069 else
1070 reloc_type = R_C60_JMP_SLOT;
1071 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1072 sym_index);
1073 }
1074 break;
1075 #elif defined(TCC_TARGET_X86_64)
1076 case R_X86_64_GOT32:
1077 case R_X86_64_GOTTPOFF:
1078 case R_X86_64_GOTPCREL:
1079 case R_X86_64_PLT32:
1080 if (!s1->got)
1081 build_got(s1);
1082 if (type == R_X86_64_GOT32 || type == R_X86_64_PLT32) {
1083 sym_index = ELFW(R_SYM)(rel->r_info);
1084 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1085 /* look at the symbol got offset. If none, then add one */
1086 if (type == R_X86_64_GOT32)
1087 reloc_type = R_X86_64_GLOB_DAT;
1088 else
1089 reloc_type = R_X86_64_JUMP_SLOT;
1090 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1091 sym_index);
1092 }
1093 break;
1094 #else
1095 #error unsupported CPU
1096 #endif
1097 default:
1098 break;
1099 }
1100 }
1101 }
1102 }
1103
1104 static Section *new_symtab(TCCState *s1,
1105 const char *symtab_name, int sh_type, int sh_flags,
1106 const char *strtab_name,
1107 const char *hash_name, int hash_sh_flags)
1108 {
1109 Section *symtab, *strtab, *hash;
1110 int *ptr, nb_buckets;
1111
1112 symtab = new_section(s1, symtab_name, sh_type, sh_flags);
1113 symtab->sh_entsize = sizeof(ElfW(Sym));
1114 strtab = new_section(s1, strtab_name, SHT_STRTAB, sh_flags);
1115 put_elf_str(strtab, "");
1116 symtab->link = strtab;
1117 put_elf_sym(symtab, 0, 0, 0, 0, 0, NULL);
1118
1119 nb_buckets = 1;
1120
1121 hash = new_section(s1, hash_name, SHT_HASH, hash_sh_flags);
1122 hash->sh_entsize = sizeof(int);
1123 symtab->hash = hash;
1124 hash->link = symtab;
1125
1126 ptr = section_ptr_add(hash, (2 + nb_buckets + 1) * sizeof(int));
1127 ptr[0] = nb_buckets;
1128 ptr[1] = 1;
1129 memset(ptr + 2, 0, (nb_buckets + 1) * sizeof(int));
1130 return symtab;
1131 }
1132
1133 /* put dynamic tag */
1134 static void put_dt(Section *dynamic, int dt, unsigned long val)
1135 {
1136 ElfW(Dyn) *dyn;
1137 dyn = section_ptr_add(dynamic, sizeof(ElfW(Dyn)));
1138 dyn->d_tag = dt;
1139 dyn->d_un.d_val = val;
1140 }
1141
1142 static void add_init_array_defines(TCCState *s1, const char *section_name)
1143 {
1144 Section *s;
1145 long end_offset;
1146 char sym_start[1024];
1147 char sym_end[1024];
1148
1149 snprintf(sym_start, sizeof(sym_start), "__%s_start", section_name + 1);
1150 snprintf(sym_end, sizeof(sym_end), "__%s_end", section_name + 1);
1151
1152 s = find_section(s1, section_name);
1153 if (!s) {
1154 end_offset = 0;
1155 s = data_section;
1156 } else {
1157 end_offset = s->data_offset;
1158 }
1159
1160 add_elf_sym(symtab_section,
1161 0, 0,
1162 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1163 s->sh_num, sym_start);
1164 add_elf_sym(symtab_section,
1165 end_offset, 0,
1166 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1167 s->sh_num, sym_end);
1168 }
1169
1170 /* add tcc runtime libraries */
1171 static void tcc_add_runtime(TCCState *s1)
1172 {
1173 #if defined(CONFIG_TCC_BCHECK) || !defined(CONFIG_USE_LIBGCC)
1174 char buf[1024];
1175 #endif
1176
1177 #ifdef CONFIG_TCC_BCHECK
1178 if (do_bounds_check) {
1179 unsigned long *ptr;
1180 Section *init_section;
1181 unsigned char *pinit;
1182 int sym_index;
1183
1184 /* XXX: add an object file to do that */
1185 ptr = section_ptr_add(bounds_section, sizeof(unsigned long));
1186 *ptr = 0;
1187 add_elf_sym(symtab_section, 0, 0,
1188 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1189 bounds_section->sh_num, "__bounds_start");
1190 /* add bound check code */
1191 snprintf(buf, sizeof(buf), "%s/%s", tcc_lib_path, "bcheck.o");
1192 tcc_add_file(s1, buf);
1193 #ifdef TCC_TARGET_I386
1194 if (s1->output_type != TCC_OUTPUT_MEMORY) {
1195 /* add 'call __bound_init()' in .init section */
1196 init_section = find_section(s1, ".init");
1197 pinit = section_ptr_add(init_section, 5);
1198 pinit[0] = 0xe8;
1199 put32(pinit + 1, -4);
1200 sym_index = find_elf_sym(symtab_section, "__bound_init");
1201 put_elf_reloc(symtab_section, init_section,
1202 init_section->data_offset - 4, R_386_PC32, sym_index);
1203 }
1204 #endif
1205 }
1206 #endif
1207 /* add libc */
1208 if (!s1->nostdlib) {
1209 tcc_add_library(s1, "c");
1210
1211 #ifdef CONFIG_USE_LIBGCC
1212 tcc_add_file(s1, CONFIG_SYSROOT "/lib/libgcc_s.so.1");
1213 #else
1214 snprintf(buf, sizeof(buf), "%s/%s", tcc_lib_path, "libtcc1.a");
1215 tcc_add_file(s1, buf);
1216 #endif
1217 }
1218 /* add crt end if not memory output */
1219 if (s1->output_type != TCC_OUTPUT_MEMORY && !s1->nostdlib) {
1220 tcc_add_file(s1, CONFIG_TCC_CRT_PREFIX "/crtn.o");
1221 }
1222 }
1223
1224 /* add various standard linker symbols (must be done after the
1225 sections are filled (for example after allocating common
1226 symbols)) */
1227 static void tcc_add_linker_symbols(TCCState *s1)
1228 {
1229 char buf[1024];
1230 int i;
1231 Section *s;
1232
1233 add_elf_sym(symtab_section,
1234 text_section->data_offset, 0,
1235 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1236 text_section->sh_num, "_etext");
1237 add_elf_sym(symtab_section,
1238 data_section->data_offset, 0,
1239 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1240 data_section->sh_num, "_edata");
1241 add_elf_sym(symtab_section,
1242 bss_section->data_offset, 0,
1243 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1244 bss_section->sh_num, "_end");
1245 /* horrible new standard ldscript defines */
1246 add_init_array_defines(s1, ".preinit_array");
1247 add_init_array_defines(s1, ".init_array");
1248 add_init_array_defines(s1, ".fini_array");
1249
1250 /* add start and stop symbols for sections whose name can be
1251 expressed in C */
1252 for(i = 1; i < s1->nb_sections; i++) {
1253 s = s1->sections[i];
1254 if (s->sh_type == SHT_PROGBITS &&
1255 (s->sh_flags & SHF_ALLOC)) {
1256 const char *p;
1257 int ch;
1258
1259 /* check if section name can be expressed in C */
1260 p = s->name;
1261 for(;;) {
1262 ch = *p;
1263 if (!ch)
1264 break;
1265 if (!isid(ch) && !isnum(ch))
1266 goto next_sec;
1267 p++;
1268 }
1269 snprintf(buf, sizeof(buf), "__start_%s", s->name);
1270 add_elf_sym(symtab_section,
1271 0, 0,
1272 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1273 s->sh_num, buf);
1274 snprintf(buf, sizeof(buf), "__stop_%s", s->name);
1275 add_elf_sym(symtab_section,
1276 s->data_offset, 0,
1277 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1278 s->sh_num, buf);
1279 }
1280 next_sec: ;
1281 }
1282 }
1283
1284 /* name of ELF interpreter */
1285 #ifdef __FreeBSD__
1286 static char elf_interp[] = "/usr/libexec/ld-elf.so.1";
1287 #else
1288 #ifdef TCC_ARM_EABI
1289 static char elf_interp[] = "/lib/ld-linux.so.3";
1290 #elif defined(TCC_TARGET_X86_64)
1291 static char elf_interp[] = "/lib/ld-linux-x86-64.so.2";
1292 #else
1293 static char elf_interp[] = "/lib/ld-linux.so.2";
1294 #endif
1295 #endif
1296
1297 static void tcc_output_binary(TCCState *s1, FILE *f,
1298 const int *section_order)
1299 {
1300 Section *s;
1301 int i, offset, size;
1302
1303 offset = 0;
1304 for(i=1;i<s1->nb_sections;i++) {
1305 s = s1->sections[section_order[i]];
1306 if (s->sh_type != SHT_NOBITS &&
1307 (s->sh_flags & SHF_ALLOC)) {
1308 while (offset < s->sh_offset) {
1309 fputc(0, f);
1310 offset++;
1311 }
1312 size = s->sh_size;
1313 fwrite(s->data, 1, size, f);
1314 offset += size;
1315 }
1316 }
1317 }
1318
1319 /* output an ELF file */
1320 /* XXX: suppress unneeded sections */
1321 int elf_output_file(TCCState *s1, const char *filename)
1322 {
1323 ElfW(Ehdr) ehdr;
1324 FILE *f;
1325 int fd, mode, ret;
1326 int *section_order;
1327 int shnum, i, phnum, file_offset, offset, size, j, tmp, sh_order_index, k;
1328 unsigned long addr;
1329 Section *strsec, *s;
1330 ElfW(Shdr) shdr, *sh;
1331 ElfW(Phdr) *phdr, *ph;
1332 Section *interp, *dynamic, *dynstr;
1333 unsigned long saved_dynamic_data_offset;
1334 ElfW(Sym) *sym;
1335 int type, file_type;
1336 unsigned long rel_addr, rel_size;
1337
1338 file_type = s1->output_type;
1339 s1->nb_errors = 0;
1340
1341 if (file_type != TCC_OUTPUT_OBJ) {
1342 tcc_add_runtime(s1);
1343 }
1344
1345 phdr = NULL;
1346 section_order = NULL;
1347 interp = NULL;
1348 dynamic = NULL;
1349 dynstr = NULL; /* avoid warning */
1350 saved_dynamic_data_offset = 0; /* avoid warning */
1351
1352 if (file_type != TCC_OUTPUT_OBJ) {
1353 relocate_common_syms();
1354
1355 tcc_add_linker_symbols(s1);
1356
1357 if (!s1->static_link) {
1358 const char *name;
1359 int sym_index, index;
1360 ElfW(Sym) *esym, *sym_end;
1361
1362 if (file_type == TCC_OUTPUT_EXE) {
1363 char *ptr;
1364 /* add interpreter section only if executable */
1365 interp = new_section(s1, ".interp", SHT_PROGBITS, SHF_ALLOC);
1366 interp->sh_addralign = 1;
1367 ptr = section_ptr_add(interp, sizeof(elf_interp));
1368 strcpy(ptr, elf_interp);
1369 }
1370
1371 /* add dynamic symbol table */
1372 s1->dynsym = new_symtab(s1, ".dynsym", SHT_DYNSYM, SHF_ALLOC,
1373 ".dynstr",
1374 ".hash", SHF_ALLOC);
1375 dynstr = s1->dynsym->link;
1376
1377 /* add dynamic section */
1378 dynamic = new_section(s1, ".dynamic", SHT_DYNAMIC,
1379 SHF_ALLOC | SHF_WRITE);
1380 dynamic->link = dynstr;
1381 dynamic->sh_entsize = sizeof(ElfW(Dyn));
1382
1383 /* add PLT */
1384 s1->plt = new_section(s1, ".plt", SHT_PROGBITS,
1385 SHF_ALLOC | SHF_EXECINSTR);
1386 s1->plt->sh_entsize = 4;
1387
1388 build_got(s1);
1389
1390 /* scan for undefined symbols and see if they are in the
1391 dynamic symbols. If a symbol STT_FUNC is found, then we
1392 add it in the PLT. If a symbol STT_OBJECT is found, we
1393 add it in the .bss section with a suitable relocation */
1394 sym_end = (ElfW(Sym) *)(symtab_section->data +
1395 symtab_section->data_offset);
1396 if (file_type == TCC_OUTPUT_EXE) {
1397 for(sym = (ElfW(Sym) *)symtab_section->data + 1;
1398 sym < sym_end;
1399 sym++) {
1400 if (sym->st_shndx == SHN_UNDEF) {
1401 name = symtab_section->link->data + sym->st_name;
1402 sym_index = find_elf_sym(s1->dynsymtab_section, name);
1403 if (sym_index) {
1404 esym = &((ElfW(Sym) *)s1->dynsymtab_section->data)[sym_index];
1405 type = ELFW(ST_TYPE)(esym->st_info);
1406 if (type == STT_FUNC) {
1407 put_got_entry(s1, R_JMP_SLOT, esym->st_size,
1408 esym->st_info,
1409 sym - (ElfW(Sym) *)symtab_section->data);
1410 } else if (type == STT_OBJECT) {
1411 unsigned long offset;
1412 offset = bss_section->data_offset;
1413 /* XXX: which alignment ? */
1414 offset = (offset + 16 - 1) & -16;
1415 index = put_elf_sym(s1->dynsym, offset, esym->st_size,
1416 esym->st_info, 0,
1417 bss_section->sh_num, name);
1418 put_elf_reloc(s1->dynsym, bss_section,
1419 offset, R_COPY, index);
1420 offset += esym->st_size;
1421 bss_section->data_offset = offset;
1422 }
1423 } else {
1424 /* STB_WEAK undefined symbols are accepted */
1425 /* XXX: _fp_hw seems to be part of the ABI, so we ignore
1426 it */
1427 if (ELFW(ST_BIND)(sym->st_info) == STB_WEAK ||
1428 !strcmp(name, "_fp_hw")) {
1429 } else {
1430 error_noabort("undefined symbol '%s'", name);
1431 }
1432 }
1433 } else if (s1->rdynamic &&
1434 ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
1435 /* if -rdynamic option, then export all non
1436 local symbols */
1437 name = symtab_section->link->data + sym->st_name;
1438 put_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
1439 sym->st_info, 0,
1440 sym->st_shndx, name);
1441 }
1442 }
1443
1444 if (s1->nb_errors)
1445 goto fail;
1446
1447 /* now look at unresolved dynamic symbols and export
1448 corresponding symbol */
1449 sym_end = (ElfW(Sym) *)(s1->dynsymtab_section->data +
1450 s1->dynsymtab_section->data_offset);
1451 for(esym = (ElfW(Sym) *)s1->dynsymtab_section->data + 1;
1452 esym < sym_end;
1453 esym++) {
1454 if (esym->st_shndx == SHN_UNDEF) {
1455 name = s1->dynsymtab_section->link->data + esym->st_name;
1456 sym_index = find_elf_sym(symtab_section, name);
1457 if (sym_index) {
1458 /* XXX: avoid adding a symbol if already
1459 present because of -rdynamic ? */
1460 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1461 put_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
1462 sym->st_info, 0,
1463 sym->st_shndx, name);
1464 } else {
1465 if (ELFW(ST_BIND)(esym->st_info) == STB_WEAK) {
1466 /* weak symbols can stay undefined */
1467 } else {
1468 warning("undefined dynamic symbol '%s'", name);
1469 }
1470 }
1471 }
1472 }
1473 } else {
1474 int nb_syms;
1475 /* shared library case : we simply export all the global symbols */
1476 nb_syms = symtab_section->data_offset / sizeof(ElfW(Sym));
1477 s1->symtab_to_dynsym = tcc_mallocz(sizeof(int) * nb_syms);
1478 for(sym = (ElfW(Sym) *)symtab_section->data + 1;
1479 sym < sym_end;
1480 sym++) {
1481 if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
1482 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1483 if (ELFW(ST_TYPE)(sym->st_info) == STT_FUNC &&
1484 sym->st_shndx == SHN_UNDEF) {
1485 put_got_entry(s1, R_JMP_SLOT, sym->st_size,
1486 sym->st_info,
1487 sym - (ElfW(Sym) *)symtab_section->data);
1488 }
1489 else if (ELFW(ST_TYPE)(sym->st_info) == STT_OBJECT) {
1490 put_got_entry(s1, R_X86_64_GLOB_DAT, sym->st_size,
1491 sym->st_info,
1492 sym - (ElfW(Sym) *)symtab_section->data);
1493 }
1494 else
1495 #endif
1496 {
1497 name = symtab_section->link->data + sym->st_name;
1498 index = put_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
1499 sym->st_info, 0,
1500 sym->st_shndx, name);
1501 s1->symtab_to_dynsym[sym -
1502 (ElfW(Sym) *)symtab_section->data] =
1503 index;
1504 }
1505 }
1506 }
1507 }
1508
1509 build_got_entries(s1);
1510
1511 /* add a list of needed dlls */
1512 for(i = 0; i < s1->nb_loaded_dlls; i++) {
1513 DLLReference *dllref = s1->loaded_dlls[i];
1514 if (dllref->level == 0)
1515 put_dt(dynamic, DT_NEEDED, put_elf_str(dynstr, dllref->name));
1516 }
1517 /* XXX: currently, since we do not handle PIC code, we
1518 must relocate the readonly segments */
1519 if (file_type == TCC_OUTPUT_DLL) {
1520 if (s1->soname)
1521 put_dt(dynamic, DT_SONAME, put_elf_str(dynstr, s1->soname));
1522 put_dt(dynamic, DT_TEXTREL, 0);
1523 }
1524
1525 /* add necessary space for other entries */
1526 saved_dynamic_data_offset = dynamic->data_offset;
1527 dynamic->data_offset += sizeof(ElfW(Dyn)) * 9;
1528 } else {
1529 /* still need to build got entries in case of static link */
1530 build_got_entries(s1);
1531 }
1532 }
1533
1534 memset(&ehdr, 0, sizeof(ehdr));
1535
1536 /* we add a section for symbols */
1537 strsec = new_section(s1, ".shstrtab", SHT_STRTAB, 0);
1538 put_elf_str(strsec, "");
1539
1540 /* compute number of sections */
1541 shnum = s1->nb_sections;
1542
1543 /* this array is used to reorder sections in the output file */
1544 section_order = tcc_malloc(sizeof(int) * shnum);
1545 section_order[0] = 0;
1546 sh_order_index = 1;
1547
1548 /* compute number of program headers */
1549 switch(file_type) {
1550 default:
1551 case TCC_OUTPUT_OBJ:
1552 phnum = 0;
1553 break;
1554 case TCC_OUTPUT_EXE:
1555 if (!s1->static_link)
1556 phnum = 4;
1557 else
1558 phnum = 2;
1559 break;
1560 case TCC_OUTPUT_DLL:
1561 phnum = 3;
1562 break;
1563 }
1564
1565 /* allocate strings for section names and decide if an unallocated
1566 section should be output */
1567 /* NOTE: the strsec section comes last, so its size is also
1568 correct ! */
1569 for(i = 1; i < s1->nb_sections; i++) {
1570 s = s1->sections[i];
1571 s->sh_name = put_elf_str(strsec, s->name);
1572 #if 0 //gr
1573 printf("section: f=%08x t=%08x i=%08x %s %s\n",
1574 s->sh_flags,
1575 s->sh_type,
1576 s->sh_info,
1577 s->name,
1578 s->reloc ? s->reloc->name : "n"
1579 );
1580 #endif
1581 /* when generating a DLL, we include relocations but we may
1582 patch them */
1583 if (file_type == TCC_OUTPUT_DLL &&
1584 s->sh_type == SHT_RELX &&
1585 !(s->sh_flags & SHF_ALLOC)) {
1586 /* //gr: avoid bogus relocs for empty (debug) sections */
1587 if (s1->sections[s->sh_info]->sh_flags & SHF_ALLOC)
1588 prepare_dynamic_rel(s1, s);
1589 else if (do_debug)
1590 s->sh_size = s->data_offset;
1591 } else if (do_debug ||
1592 file_type == TCC_OUTPUT_OBJ ||
1593 (s->sh_flags & SHF_ALLOC) ||
1594 i == (s1->nb_sections - 1)) {
1595 /* we output all sections if debug or object file */
1596 s->sh_size = s->data_offset;
1597 }
1598 }
1599
1600 /* allocate program segment headers */
1601 phdr = tcc_mallocz(phnum * sizeof(ElfW(Phdr)));
1602
1603 if (s1->output_format == TCC_OUTPUT_FORMAT_ELF) {
1604 file_offset = sizeof(ElfW(Ehdr)) + phnum * sizeof(ElfW(Phdr));
1605 } else {
1606 file_offset = 0;
1607 }
1608 if (phnum > 0) {
1609 /* compute section to program header mapping */
1610 if (s1->has_text_addr) {
1611 int a_offset, p_offset;
1612 addr = s1->text_addr;
1613 /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
1614 ELF_PAGE_SIZE */
1615 a_offset = addr & (ELF_PAGE_SIZE - 1);
1616 p_offset = file_offset & (ELF_PAGE_SIZE - 1);
1617 if (a_offset < p_offset)
1618 a_offset += ELF_PAGE_SIZE;
1619 file_offset += (a_offset - p_offset);
1620 } else {
1621 if (file_type == TCC_OUTPUT_DLL)
1622 addr = 0;
1623 else
1624 addr = ELF_START_ADDR;
1625 /* compute address after headers */
1626 addr += (file_offset & (ELF_PAGE_SIZE - 1));
1627 }
1628
1629 /* dynamic relocation table information, for .dynamic section */
1630 rel_size = 0;
1631 rel_addr = 0;
1632
1633 /* leave one program header for the program interpreter */
1634 ph = &phdr[0];
1635 if (interp)
1636 ph++;
1637
1638 for(j = 0; j < 2; j++) {
1639 ph->p_type = PT_LOAD;
1640 if (j == 0)
1641 ph->p_flags = PF_R | PF_X;
1642 else
1643 ph->p_flags = PF_R | PF_W;
1644 ph->p_align = ELF_PAGE_SIZE;
1645
1646 /* we do the following ordering: interp, symbol tables,
1647 relocations, progbits, nobits */
1648 /* XXX: do faster and simpler sorting */
1649 for(k = 0; k < 5; k++) {
1650 for(i = 1; i < s1->nb_sections; i++) {
1651 s = s1->sections[i];
1652 /* compute if section should be included */
1653 if (j == 0) {
1654 if ((s->sh_flags & (SHF_ALLOC | SHF_WRITE)) !=
1655 SHF_ALLOC)
1656 continue;
1657 } else {
1658 if ((s->sh_flags & (SHF_ALLOC | SHF_WRITE)) !=
1659 (SHF_ALLOC | SHF_WRITE))
1660 continue;
1661 }
1662 if (s == interp) {
1663 if (k != 0)
1664 continue;
1665 } else if (s->sh_type == SHT_DYNSYM ||
1666 s->sh_type == SHT_STRTAB ||
1667 s->sh_type == SHT_HASH) {
1668 if (k != 1)
1669 continue;
1670 } else if (s->sh_type == SHT_RELX) {
1671 if (k != 2)
1672 continue;
1673 } else if (s->sh_type == SHT_NOBITS) {
1674 if (k != 4)
1675 continue;
1676 } else {
1677 if (k != 3)
1678 continue;
1679 }
1680 section_order[sh_order_index++] = i;
1681
1682 /* section matches: we align it and add its size */
1683 tmp = addr;
1684 addr = (addr + s->sh_addralign - 1) &
1685 ~(s->sh_addralign - 1);
1686 file_offset += addr - tmp;
1687 s->sh_offset = file_offset;
1688 s->sh_addr = addr;
1689
1690 /* update program header infos */
1691 if (ph->p_offset == 0) {
1692 ph->p_offset = file_offset;
1693 ph->p_vaddr = addr;
1694 ph->p_paddr = ph->p_vaddr;
1695 }
1696 /* update dynamic relocation infos */
1697 if (s->sh_type == SHT_RELX) {
1698 if (rel_size == 0)
1699 rel_addr = addr;
1700 rel_size += s->sh_size;
1701 }
1702 addr += s->sh_size;
1703 if (s->sh_type != SHT_NOBITS)
1704 file_offset += s->sh_size;
1705 }
1706 }
1707 ph->p_filesz = file_offset - ph->p_offset;
1708 ph->p_memsz = addr - ph->p_vaddr;
1709 ph++;
1710 if (j == 0) {
1711 if (s1->output_format == TCC_OUTPUT_FORMAT_ELF) {
1712 /* if in the middle of a page, we duplicate the page in
1713 memory so that one copy is RX and the other is RW */
1714 if ((addr & (ELF_PAGE_SIZE - 1)) != 0)
1715 addr += ELF_PAGE_SIZE;
1716 } else {
1717 addr = (addr + ELF_PAGE_SIZE - 1) & ~(ELF_PAGE_SIZE - 1);
1718 file_offset = (file_offset + ELF_PAGE_SIZE - 1) &
1719 ~(ELF_PAGE_SIZE - 1);
1720 }
1721 }
1722 }
1723
1724 /* if interpreter, then add corresponing program header */
1725 if (interp) {
1726 ph = &phdr[0];
1727
1728 ph->p_type = PT_INTERP;
1729 ph->p_offset = interp->sh_offset;
1730 ph->p_vaddr = interp->sh_addr;
1731 ph->p_paddr = ph->p_vaddr;
1732 ph->p_filesz = interp->sh_size;
1733 ph->p_memsz = interp->sh_size;
1734 ph->p_flags = PF_R;
1735 ph->p_align = interp->sh_addralign;
1736 }
1737
1738 /* if dynamic section, then add corresponing program header */
1739 if (dynamic) {
1740 ElfW(Sym) *sym_end;
1741
1742 ph = &phdr[phnum - 1];
1743
1744 ph->p_type = PT_DYNAMIC;
1745 ph->p_offset = dynamic->sh_offset;
1746 ph->p_vaddr = dynamic->sh_addr;
1747 ph->p_paddr = ph->p_vaddr;
1748 ph->p_filesz = dynamic->sh_size;
1749 ph->p_memsz = dynamic->sh_size;
1750 ph->p_flags = PF_R | PF_W;
1751 ph->p_align = dynamic->sh_addralign;
1752
1753 /* put GOT dynamic section address */
1754 put32(s1->got->data, dynamic->sh_addr);
1755
1756 /* relocate the PLT */
1757 if (file_type == TCC_OUTPUT_EXE
1758 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1759 || file_type == TCC_OUTPUT_DLL
1760 #endif
1761 ) {
1762 uint8_t *p, *p_end;
1763
1764 p = s1->plt->data;
1765 p_end = p + s1->plt->data_offset;
1766 if (p < p_end) {
1767 #if defined(TCC_TARGET_I386)
1768 put32(p + 2, get32(p + 2) + s1->got->sh_addr);
1769 put32(p + 8, get32(p + 8) + s1->got->sh_addr);
1770 p += 16;
1771 while (p < p_end) {
1772 put32(p + 2, get32(p + 2) + s1->got->sh_addr);
1773 p += 16;
1774 }
1775 #elif defined(TCC_TARGET_X86_64)
1776 int x = s1->got->sh_addr - s1->plt->sh_addr - 6;
1777 put32(p + 2, get32(p + 2) + x);
1778 put32(p + 8, get32(p + 8) + x - 6);
1779 p += 16;
1780 while (p < p_end) {
1781 put32(p + 2, get32(p + 2) + x + s1->plt->data - p);
1782 p += 16;
1783 }
1784 #elif defined(TCC_TARGET_ARM)
1785 int x;
1786 x=s1->got->sh_addr - s1->plt->sh_addr - 12;
1787 p +=16;
1788 while (p < p_end) {
1789 put32(p + 12, x + get32(p + 12) + s1->plt->data - p);
1790 p += 16;
1791 }
1792 #elif defined(TCC_TARGET_C67)
1793 /* XXX: TODO */
1794 #else
1795 #error unsupported CPU
1796 #endif
1797 }
1798 }
1799
1800 /* relocate symbols in .dynsym */
1801 sym_end = (ElfW(Sym) *)(s1->dynsym->data + s1->dynsym->data_offset);
1802 for(sym = (ElfW(Sym) *)s1->dynsym->data + 1;
1803 sym < sym_end;
1804 sym++) {
1805 if (sym->st_shndx == SHN_UNDEF) {
1806 /* relocate to the PLT if the symbol corresponds
1807 to a PLT entry */
1808 if (sym->st_value)
1809 sym->st_value += s1->plt->sh_addr;
1810 } else if (sym->st_shndx < SHN_LORESERVE) {
1811 /* do symbol relocation */
1812 sym->st_value += s1->sections[sym->st_shndx]->sh_addr;
1813 }
1814 }
1815
1816 /* put dynamic section entries */
1817 dynamic->data_offset = saved_dynamic_data_offset;
1818 put_dt(dynamic, DT_HASH, s1->dynsym->hash->sh_addr);
1819 put_dt(dynamic, DT_STRTAB, dynstr->sh_addr);
1820 put_dt(dynamic, DT_SYMTAB, s1->dynsym->sh_addr);
1821 put_dt(dynamic, DT_STRSZ, dynstr->data_offset);
1822 put_dt(dynamic, DT_SYMENT, sizeof(ElfW(Sym)));
1823 #ifdef TCC_TARGET_X86_64
1824 put_dt(dynamic, DT_RELA, rel_addr);
1825 put_dt(dynamic, DT_RELASZ, rel_size);
1826 put_dt(dynamic, DT_RELAENT, sizeof(ElfW_Rel));
1827 #else
1828 put_dt(dynamic, DT_REL, rel_addr);
1829 put_dt(dynamic, DT_RELSZ, rel_size);
1830 put_dt(dynamic, DT_RELENT, sizeof(ElfW_Rel));
1831 #endif
1832 if (do_debug)
1833 put_dt(dynamic, DT_DEBUG, 0);
1834 put_dt(dynamic, DT_NULL, 0);
1835 }
1836
1837 ehdr.e_phentsize = sizeof(ElfW(Phdr));
1838 ehdr.e_phnum = phnum;
1839 ehdr.e_phoff = sizeof(ElfW(Ehdr));
1840 }
1841
1842 /* all other sections come after */
1843 for(i = 1; i < s1->nb_sections; i++) {
1844 s = s1->sections[i];
1845 if (phnum > 0 && (s->sh_flags & SHF_ALLOC))
1846 continue;
1847 section_order[sh_order_index++] = i;
1848
1849 file_offset = (file_offset + s->sh_addralign - 1) &
1850 ~(s->sh_addralign - 1);
1851 s->sh_offset = file_offset;
1852 if (s->sh_type != SHT_NOBITS)
1853 file_offset += s->sh_size;
1854 }
1855
1856 /* if building executable or DLL, then relocate each section
1857 except the GOT which is already relocated */
1858 if (file_type != TCC_OUTPUT_OBJ) {
1859 relocate_syms(s1, 0);
1860
1861 if (s1->nb_errors != 0) {
1862 fail:
1863 ret = -1;
1864 goto the_end;
1865 }
1866
1867 /* relocate sections */
1868 /* XXX: ignore sections with allocated relocations ? */
1869 for(i = 1; i < s1->nb_sections; i++) {
1870 s = s1->sections[i];
1871 if (s->reloc && s != s1->got && (s->sh_flags & SHF_ALLOC)) //gr
1872 relocate_section(s1, s);
1873 }
1874
1875 /* relocate relocation entries if the relocation tables are
1876 allocated in the executable */
1877 for(i = 1; i < s1->nb_sections; i++) {
1878 s = s1->sections[i];
1879 if ((s->sh_flags & SHF_ALLOC) &&
1880 s->sh_type == SHT_RELX) {
1881 relocate_rel(s1, s);
1882 }
1883 }
1884
1885 /* get entry point address */
1886 if (file_type == TCC_OUTPUT_EXE)
1887 ehdr.e_entry = (unsigned long)tcc_get_symbol_err(s1, "_start");
1888 else
1889 ehdr.e_entry = text_section->sh_addr; /* XXX: is it correct ? */
1890 }
1891
1892 /* write elf file */
1893 if (file_type == TCC_OUTPUT_OBJ)
1894 mode = 0666;
1895 else
1896 mode = 0777;
1897 fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, mode);
1898 if (fd < 0) {
1899 error_noabort("could not write '%s'", filename);
1900 goto fail;
1901 }
1902 f = fdopen(fd, "wb");
1903 if (verbose)
1904 printf("<- %s\n", filename);
1905
1906 #ifdef TCC_TARGET_COFF
1907 if (s1->output_format == TCC_OUTPUT_FORMAT_COFF) {
1908 tcc_output_coff(s1, f);
1909 } else
1910 #endif
1911 if (s1->output_format == TCC_OUTPUT_FORMAT_ELF) {
1912 sort_syms(s1, symtab_section);
1913
1914 /* align to 4 */
1915 file_offset = (file_offset + 3) & -4;
1916
1917 /* fill header */
1918 ehdr.e_ident[0] = ELFMAG0;
1919 ehdr.e_ident[1] = ELFMAG1;
1920 ehdr.e_ident[2] = ELFMAG2;
1921 ehdr.e_ident[3] = ELFMAG3;
1922 ehdr.e_ident[4] = TCC_ELFCLASS;
1923 ehdr.e_ident[5] = ELFDATA2LSB;
1924 ehdr.e_ident[6] = EV_CURRENT;
1925 #ifdef __FreeBSD__
1926 ehdr.e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
1927 #endif
1928 #ifdef TCC_TARGET_ARM
1929 #ifdef TCC_ARM_EABI
1930 ehdr.e_ident[EI_OSABI] = 0;
1931 ehdr.e_flags = 4 << 24;
1932 #else
1933 ehdr.e_ident[EI_OSABI] = ELFOSABI_ARM;
1934 #endif
1935 #endif
1936 switch(file_type) {
1937 default:
1938 case TCC_OUTPUT_EXE:
1939 ehdr.e_type = ET_EXEC;
1940 break;
1941 case TCC_OUTPUT_DLL:
1942 ehdr.e_type = ET_DYN;
1943 break;
1944 case TCC_OUTPUT_OBJ:
1945 ehdr.e_type = ET_REL;
1946 break;
1947 }
1948 ehdr.e_machine = EM_TCC_TARGET;
1949 ehdr.e_version = EV_CURRENT;
1950 ehdr.e_shoff = file_offset;
1951 ehdr.e_ehsize = sizeof(ElfW(Ehdr));
1952 ehdr.e_shentsize = sizeof(ElfW(Shdr));
1953 ehdr.e_shnum = shnum;
1954 ehdr.e_shstrndx = shnum - 1;
1955
1956 fwrite(&ehdr, 1, sizeof(ElfW(Ehdr)), f);
1957 fwrite(phdr, 1, phnum * sizeof(ElfW(Phdr)), f);
1958 offset = sizeof(ElfW(Ehdr)) + phnum * sizeof(ElfW(Phdr));
1959
1960 for(i=1;i<s1->nb_sections;i++) {
1961 s = s1->sections[section_order[i]];
1962 if (s->sh_type != SHT_NOBITS) {
1963 while (offset < s->sh_offset) {
1964 fputc(0, f);
1965 offset++;
1966 }
1967 size = s->sh_size;
1968 fwrite(s->data, 1, size, f);
1969 offset += size;
1970 }
1971 }
1972
1973 /* output section headers */
1974 while (offset < ehdr.e_shoff) {
1975 fputc(0, f);
1976 offset++;
1977 }
1978
1979 for(i=0;i<s1->nb_sections;i++) {
1980 sh = &shdr;
1981 memset(sh, 0, sizeof(ElfW(Shdr)));
1982 s = s1->sections[i];
1983 if (s) {
1984 sh->sh_name = s->sh_name;
1985 sh->sh_type = s->sh_type;
1986 sh->sh_flags = s->sh_flags;
1987 sh->sh_entsize = s->sh_entsize;
1988 sh->sh_info = s->sh_info;
1989 if (s->link)
1990 sh->sh_link = s->link->sh_num;
1991 sh->sh_addralign = s->sh_addralign;
1992 sh->sh_addr = s->sh_addr;
1993 sh->sh_offset = s->sh_offset;
1994 sh->sh_size = s->sh_size;
1995 }
1996 fwrite(sh, 1, sizeof(ElfW(Shdr)), f);
1997 }
1998 } else {
1999 tcc_output_binary(s1, f, section_order);
2000 }
2001 fclose(f);
2002
2003 ret = 0;
2004 the_end:
2005 tcc_free(s1->symtab_to_dynsym);
2006 tcc_free(section_order);
2007 tcc_free(phdr);
2008 tcc_free(s1->got_offsets);
2009 return ret;
2010 }
2011
2012 int tcc_output_file(TCCState *s, const char *filename)
2013 {
2014 int ret;
2015 #ifdef TCC_TARGET_PE
2016 if (s->output_type != TCC_OUTPUT_OBJ) {
2017 ret = pe_output_file(s, filename);
2018 } else
2019 #endif
2020 {
2021 ret = elf_output_file(s, filename);
2022 }
2023 return ret;
2024 }
2025
2026 static void *load_data(int fd, unsigned long file_offset, unsigned long size)
2027 {
2028 void *data;
2029
2030 data = tcc_malloc(size);
2031 lseek(fd, file_offset, SEEK_SET);
2032 read(fd, data, size);
2033 return data;
2034 }
2035
2036 typedef struct SectionMergeInfo {
2037 Section *s; /* corresponding existing section */
2038 unsigned long offset; /* offset of the new section in the existing section */
2039 uint8_t new_section; /* true if section 's' was added */
2040 uint8_t link_once; /* true if link once section */
2041 } SectionMergeInfo;
2042
2043 /* load an object file and merge it with current files */
2044 /* XXX: handle correctly stab (debug) info */
2045 static int tcc_load_object_file(TCCState *s1,
2046 int fd, unsigned long file_offset)
2047 {
2048 ElfW(Ehdr) ehdr;
2049 ElfW(Shdr) *shdr, *sh;
2050 int size, i, j, offset, offseti, nb_syms, sym_index, ret;
2051 unsigned char *strsec, *strtab;
2052 int *old_to_new_syms;
2053 char *sh_name, *name;
2054 SectionMergeInfo *sm_table, *sm;
2055 ElfW(Sym) *sym, *symtab;
2056 ElfW_Rel *rel, *rel_end;
2057 Section *s;
2058
2059 int stab_index;
2060 int stabstr_index;
2061
2062 stab_index = stabstr_index = 0;
2063
2064 if (read(fd, &ehdr, sizeof(ehdr)) != sizeof(ehdr))
2065 goto fail1;
2066 if (ehdr.e_ident[0] != ELFMAG0 ||
2067 ehdr.e_ident[1] != ELFMAG1 ||
2068 ehdr.e_ident[2] != ELFMAG2 ||
2069 ehdr.e_ident[3] != ELFMAG3)
2070 goto fail1;
2071 /* test if object file */
2072 if (ehdr.e_type != ET_REL)
2073 goto fail1;
2074 /* test CPU specific stuff */
2075 if (ehdr.e_ident[5] != ELFDATA2LSB ||
2076 ehdr.e_machine != EM_TCC_TARGET) {
2077 fail1:
2078 error_noabort("invalid object file");
2079 return -1;
2080 }
2081 /* read sections */
2082 shdr = load_data(fd, file_offset + ehdr.e_shoff,
2083 sizeof(ElfW(Shdr)) * ehdr.e_shnum);
2084 sm_table = tcc_mallocz(sizeof(SectionMergeInfo) * ehdr.e_shnum);
2085
2086 /* load section names */
2087 sh = &shdr[ehdr.e_shstrndx];
2088 strsec = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
2089
2090 /* load symtab and strtab */
2091 old_to_new_syms = NULL;
2092 symtab = NULL;
2093 strtab = NULL;
2094 nb_syms = 0;
2095 for(i = 1; i < ehdr.e_shnum; i++) {
2096 sh = &shdr[i];
2097 if (sh->sh_type == SHT_SYMTAB) {
2098 if (symtab) {
2099 error_noabort("object must contain only one symtab");
2100 fail:
2101 ret = -1;
2102 goto the_end;
2103 }
2104 nb_syms = sh->sh_size / sizeof(ElfW(Sym));
2105 symtab = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
2106 sm_table[i].s = symtab_section;
2107
2108 /* now load strtab */
2109 sh = &shdr[sh->sh_link];
2110 strtab = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
2111 }
2112 }
2113
2114 /* now examine each section and try to merge its content with the
2115 ones in memory */
2116 for(i = 1; i < ehdr.e_shnum; i++) {
2117 /* no need to examine section name strtab */
2118 if (i == ehdr.e_shstrndx)
2119 continue;
2120 sh = &shdr[i];
2121 sh_name = strsec + sh->sh_name;
2122 /* ignore sections types we do not handle */
2123 if (sh->sh_type != SHT_PROGBITS &&
2124 sh->sh_type != SHT_RELX &&
2125 #ifdef TCC_ARM_EABI
2126 sh->sh_type != SHT_ARM_EXIDX &&
2127 #endif
2128 sh->sh_type != SHT_NOBITS &&
2129 strcmp(sh_name, ".stabstr")
2130 )
2131 continue;
2132 if (sh->sh_addralign < 1)
2133 sh->sh_addralign = 1;
2134 /* find corresponding section, if any */
2135 for(j = 1; j < s1->nb_sections;j++) {
2136 s = s1->sections[j];
2137 if (!strcmp(s->name, sh_name)) {
2138 if (!strncmp(sh_name, ".gnu.linkonce",
2139 sizeof(".gnu.linkonce") - 1)) {
2140 /* if a 'linkonce' section is already present, we
2141 do not add it again. It is a little tricky as
2142 symbols can still be defined in
2143 it. */
2144 sm_table[i].link_once = 1;
2145 goto next;
2146 } else {
2147 goto found;
2148 }
2149 }
2150 }
2151 /* not found: create new section */
2152 s = new_section(s1, sh_name, sh->sh_type, sh->sh_flags);
2153 /* take as much info as possible from the section. sh_link and
2154 sh_info will be updated later */
2155 s->sh_addralign = sh->sh_addralign;
2156 s->sh_entsize = sh->sh_entsize;
2157 sm_table[i].new_section = 1;
2158 found:
2159 if (sh->sh_type != s->sh_type) {
2160 error_noabort("invalid section type");
2161 goto fail;
2162 }
2163
2164 /* align start of section */
2165 offset = s->data_offset;
2166
2167 if (0 == strcmp(sh_name, ".stab")) {
2168 stab_index = i;
2169 goto no_align;
2170 }
2171 if (0 == strcmp(sh_name, ".stabstr")) {
2172 stabstr_index = i;
2173 goto no_align;
2174 }
2175
2176 size = sh->sh_addralign - 1;
2177 offset = (offset + size) & ~size;
2178 if (sh->sh_addralign > s->sh_addralign)
2179 s->sh_addralign = sh->sh_addralign;
2180 s->data_offset = offset;
2181 no_align:
2182 sm_table[i].offset = offset;
2183 sm_table[i].s = s;
2184 /* concatenate sections */
2185 size = sh->sh_size;
2186 if (sh->sh_type != SHT_NOBITS) {
2187 unsigned char *ptr;
2188 lseek(fd, file_offset + sh->sh_offset, SEEK_SET);
2189 ptr = section_ptr_add(s, size);
2190 read(fd, ptr, size);
2191 } else {
2192 s->data_offset += size;
2193 }
2194 next: ;
2195 }
2196
2197 /* //gr relocate stab strings */
2198 if (stab_index && stabstr_index) {
2199 Stab_Sym *a, *b;
2200 unsigned o;
2201 s = sm_table[stab_index].s;
2202 a = (Stab_Sym *)(s->data + sm_table[stab_index].offset);
2203 b = (Stab_Sym *)(s->data + s->data_offset);
2204 o = sm_table[stabstr_index].offset;
2205 while (a < b)
2206 a->n_strx += o, a++;
2207 }
2208
2209 /* second short pass to update sh_link and sh_info fields of new
2210 sections */
2211 for(i = 1; i < ehdr.e_shnum; i++) {
2212 s = sm_table[i].s;
2213 if (!s || !sm_table[i].new_section)
2214 continue;
2215 sh = &shdr[i];
2216 if (sh->sh_link > 0)
2217 s->link = sm_table[sh->sh_link].s;
2218 if (sh->sh_type == SHT_RELX) {
2219 s->sh_info = sm_table[sh->sh_info].s->sh_num;
2220 /* update backward link */
2221 s1->sections[s->sh_info]->reloc = s;
2222 }
2223 }
2224 sm = sm_table;
2225
2226 /* resolve symbols */
2227 old_to_new_syms = tcc_mallocz(nb_syms * sizeof(int));
2228
2229 sym = symtab + 1;
2230 for(i = 1; i < nb_syms; i++, sym++) {
2231 if (sym->st_shndx != SHN_UNDEF &&
2232 sym->st_shndx < SHN_LORESERVE) {
2233 sm = &sm_table[sym->st_shndx];
2234 if (sm->link_once) {
2235 /* if a symbol is in a link once section, we use the
2236 already defined symbol. It is very important to get
2237 correct relocations */
2238 if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
2239 name = strtab + sym->st_name;
2240 sym_index = find_elf_sym(symtab_section, name);
2241 if (sym_index)
2242 old_to_new_syms[i] = sym_index;
2243 }
2244 continue;
2245 }
2246 /* if no corresponding section added, no need to add symbol */
2247 if (!sm->s)
2248 continue;
2249 /* convert section number */
2250 sym->st_shndx = sm->s->sh_num;
2251 /* offset value */
2252 sym->st_value += sm->offset;
2253 }
2254 /* add symbol */
2255 name = strtab + sym->st_name;
2256 sym_index = add_elf_sym(symtab_section, sym->st_value, sym->st_size,
2257 sym->st_info, sym->st_other,
2258 sym->st_shndx, name);
2259 old_to_new_syms[i] = sym_index;
2260 }
2261
2262 /* third pass to patch relocation entries */
2263 for(i = 1; i < ehdr.e_shnum; i++) {
2264 s = sm_table[i].s;
2265 if (!s)
2266 continue;
2267 sh = &shdr[i];
2268 offset = sm_table[i].offset;
2269 switch(s->sh_type) {
2270 case SHT_RELX:
2271 /* take relocation offset information */
2272 offseti = sm_table[sh->sh_info].offset;
2273 rel_end = (ElfW_Rel *)(s->data + s->data_offset);
2274 for(rel = (ElfW_Rel *)(s->data + offset);
2275 rel < rel_end;
2276 rel++) {
2277 int type;
2278 unsigned sym_index;
2279 /* convert symbol index */
2280 type = ELFW(R_TYPE)(rel->r_info);
2281 sym_index = ELFW(R_SYM)(rel->r_info);
2282 /* NOTE: only one symtab assumed */
2283 if (sym_index >= nb_syms)
2284 goto invalid_reloc;
2285 sym_index = old_to_new_syms[sym_index];
2286 /* ignore link_once in rel section. */
2287 if (!sym_index && !sm->link_once) {
2288 invalid_reloc:
2289 error_noabort("Invalid relocation entry [%2d] '%s' @ %.8x",
2290 i, strsec + sh->sh_name, rel->r_offset);
2291 goto fail;
2292 }
2293 rel->r_info = ELFW(R_INFO)(sym_index, type);
2294 /* offset the relocation offset */
2295 rel->r_offset += offseti;
2296 }
2297 break;
2298 default:
2299 break;
2300 }
2301 }
2302
2303 ret = 0;
2304 the_end:
2305 tcc_free(symtab);
2306 tcc_free(strtab);
2307 tcc_free(old_to_new_syms);
2308 tcc_free(sm_table);
2309 tcc_free(strsec);
2310 tcc_free(shdr);
2311 return ret;
2312 }
2313
2314 #define ARMAG "!<arch>\012" /* For COFF and a.out archives */
2315
2316 typedef struct ArchiveHeader {
2317 char ar_name[16]; /* name of this member */
2318 char ar_date[12]; /* file mtime */
2319 char ar_uid[6]; /* owner uid; printed as decimal */
2320 char ar_gid[6]; /* owner gid; printed as decimal */
2321 char ar_mode[8]; /* file mode, printed as octal */
2322 char ar_size[10]; /* file size, printed as decimal */
2323 char ar_fmag[2]; /* should contain ARFMAG */
2324 } ArchiveHeader;
2325
2326 static int get_be32(const uint8_t *b)
2327 {
2328 return b[3] | (b[2] << 8) | (b[1] << 16) | (b[0] << 24);
2329 }
2330
2331 /* load only the objects which resolve undefined symbols */
2332 static int tcc_load_alacarte(TCCState *s1, int fd, int size)
2333 {
2334 int i, bound, nsyms, sym_index, off, ret;
2335 uint8_t *data;
2336 const char *ar_names, *p;
2337 const uint8_t *ar_index;
2338 ElfW(Sym) *sym;
2339
2340 data = tcc_malloc(size);
2341 if (read(fd, data, size) != size)
2342 goto fail;
2343 nsyms = get_be32(data);
2344 ar_index = data + 4;
2345 ar_names = ar_index + nsyms * 4;
2346
2347 do {
2348 bound = 0;
2349 for(p = ar_names, i = 0; i < nsyms; i++, p += strlen(p)+1) {
2350 sym_index = find_elf_sym(symtab_section, p);
2351 if(sym_index) {
2352 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
2353 if(sym->st_shndx == SHN_UNDEF) {
2354 off = get_be32(ar_index + i * 4) + sizeof(ArchiveHeader);
2355 #if 0
2356 printf("%5d\t%s\t%08x\n", i, p, sym->st_shndx);
2357 #endif
2358 ++bound;
2359 lseek(fd, off, SEEK_SET);
2360 if(tcc_load_object_file(s1, fd, off) < 0) {
2361 fail:
2362 ret = -1;
2363 goto the_end;
2364 }
2365 }
2366 }
2367 }
2368 } while(bound);
2369 ret = 0;
2370 the_end:
2371 tcc_free(data);
2372 return ret;
2373 }
2374
2375 /* load a '.a' file */
2376 static int tcc_load_archive(TCCState *s1, int fd)
2377 {
2378 ArchiveHeader hdr;
2379 char ar_size[11];
2380 char ar_name[17];
2381 char magic[8];
2382 int size, len, i;
2383 unsigned long file_offset;
2384
2385 /* skip magic which was already checked */
2386 read(fd, magic, sizeof(magic));
2387
2388 for(;;) {
2389 len = read(fd, &hdr, sizeof(hdr));
2390 if (len == 0)
2391 break;
2392 if (len != sizeof(hdr)) {
2393 error_noabort("invalid archive");
2394 return -1;
2395 }
2396 memcpy(ar_size, hdr.ar_size, sizeof(hdr.ar_size));
2397 ar_size[sizeof(hdr.ar_size)] = '\0';
2398 size = strtol(ar_size, NULL, 0);
2399 memcpy(ar_name, hdr.ar_name, sizeof(hdr.ar_name));
2400 for(i = sizeof(hdr.ar_name) - 1; i >= 0; i--) {
2401 if (ar_name[i] != ' ')
2402 break;
2403 }
2404 ar_name[i + 1] = '\0';
2405 // printf("name='%s' size=%d %s\n", ar_name, size, ar_size);
2406 file_offset = lseek(fd, 0, SEEK_CUR);
2407 /* align to even */
2408 size = (size + 1) & ~1;
2409 if (!strcmp(ar_name, "/")) {
2410 /* coff symbol table : we handle it */
2411 if(s1->alacarte_link)
2412 return tcc_load_alacarte(s1, fd, size);
2413 } else if (!strcmp(ar_name, "//") ||
2414 !strcmp(ar_name, "__.SYMDEF") ||
2415 !strcmp(ar_name, "__.SYMDEF/") ||
2416 !strcmp(ar_name, "ARFILENAMES/")) {
2417 /* skip symbol table or archive names */
2418 } else {
2419 if (tcc_load_object_file(s1, fd, file_offset) < 0)
2420 return -1;
2421 }
2422 lseek(fd, file_offset + size, SEEK_SET);
2423 }
2424 return 0;
2425 }
2426
2427 /* load a DLL and all referenced DLLs. 'level = 0' means that the DLL
2428 is referenced by the user (so it should be added as DT_NEEDED in
2429 the generated ELF file) */
2430 static int tcc_load_dll(TCCState *s1, int fd, const char *filename, int level)
2431 {
2432 ElfW(Ehdr) ehdr;
2433 ElfW(Shdr) *shdr, *sh, *sh1;
2434 int i, j, nb_syms, nb_dts, sym_bind, ret;
2435 ElfW(Sym) *sym, *dynsym;
2436 ElfW(Dyn) *dt, *dynamic;
2437 unsigned char *dynstr;
2438 const char *name, *soname;
2439 DLLReference *dllref;
2440
2441 read(fd, &ehdr, sizeof(ehdr));
2442
2443 /* test CPU specific stuff */
2444 if (ehdr.e_ident[5] != ELFDATA2LSB ||
2445 ehdr.e_machine != EM_TCC_TARGET) {
2446 error_noabort("bad architecture");
2447 return -1;
2448 }
2449
2450 /* read sections */
2451 shdr = load_data(fd, ehdr.e_shoff, sizeof(ElfW(Shdr)) * ehdr.e_shnum);
2452
2453 /* load dynamic section and dynamic symbols */
2454 nb_syms = 0;
2455 nb_dts = 0;
2456 dynamic = NULL;
2457 dynsym = NULL; /* avoid warning */
2458 dynstr = NULL; /* avoid warning */
2459 for(i = 0, sh = shdr; i < ehdr.e_shnum; i++, sh++) {
2460 switch(sh->sh_type) {
2461 case SHT_DYNAMIC:
2462 nb_dts = sh->sh_size / sizeof(ElfW(Dyn));
2463 dynamic = load_data(fd, sh->sh_offset, sh->sh_size);
2464 break;
2465 case SHT_DYNSYM:
2466 nb_syms = sh->sh_size / sizeof(ElfW(Sym));
2467 dynsym = load_data(fd, sh->sh_offset, sh->sh_size);
2468 sh1 = &shdr[sh->sh_link];
2469 dynstr = load_data(fd, sh1->sh_offset, sh1->sh_size);
2470 break;
2471 default:
2472 break;
2473 }
2474 }
2475
2476 /* compute the real library name */
2477 soname = tcc_basename(filename);
2478
2479 for(i = 0, dt = dynamic; i < nb_dts; i++, dt++) {
2480 if (dt->d_tag == DT_SONAME) {
2481 soname = dynstr + dt->d_un.d_val;
2482 }
2483 }
2484
2485 /* if the dll is already loaded, do not load it */
2486 for(i = 0; i < s1->nb_loaded_dlls; i++) {
2487 dllref = s1->loaded_dlls[i];
2488 if (!strcmp(soname, dllref->name)) {
2489 /* but update level if needed */
2490 if (level < dllref->level)
2491 dllref->level = level;
2492 ret = 0;
2493 goto the_end;
2494 }
2495 }
2496
2497 // printf("loading dll '%s'\n", soname);
2498
2499 /* add the dll and its level */
2500 dllref = tcc_mallocz(sizeof(DLLReference) + strlen(soname));
2501 dllref->level = level;
2502 strcpy(dllref->name, soname);
2503 dynarray_add((void ***)&s1->loaded_dlls, &s1->nb_loaded_dlls, dllref);
2504
2505 /* add dynamic symbols in dynsym_section */
2506 for(i = 1, sym = dynsym + 1; i < nb_syms; i++, sym++) {
2507 sym_bind = ELFW(ST_BIND)(sym->st_info);
2508 if (sym_bind == STB_LOCAL)
2509 continue;
2510 name = dynstr + sym->st_name;
2511 add_elf_sym(s1->dynsymtab_section, sym->st_value, sym->st_size,
2512 sym->st_info, sym->st_other, sym->st_shndx, name);
2513 }
2514
2515 /* load all referenced DLLs */
2516 for(i = 0, dt = dynamic; i < nb_dts; i++, dt++) {
2517 switch(dt->d_tag) {
2518 case DT_NEEDED:
2519 name = dynstr + dt->d_un.d_val;
2520 for(j = 0; j < s1->nb_loaded_dlls; j++) {
2521 dllref = s1->loaded_dlls[j];
2522 if (!strcmp(name, dllref->name))
2523 goto already_loaded;
2524 }
2525 if (tcc_add_dll(s1, name, AFF_REFERENCED_DLL) < 0) {
2526 error_noabort("referenced dll '%s' not found", name);
2527 ret = -1;
2528 goto the_end;
2529 }
2530 already_loaded:
2531 break;
2532 }
2533 }
2534 ret = 0;
2535 the_end:
2536 tcc_free(dynstr);
2537 tcc_free(dynsym);
2538 tcc_free(dynamic);
2539 tcc_free(shdr);
2540 return ret;
2541 }
2542
2543 #define LD_TOK_NAME 256
2544 #define LD_TOK_EOF (-1)
2545
2546 /* return next ld script token */
2547 static int ld_next(TCCState *s1, char *name, int name_size)
2548 {
2549 int c;
2550 char *q;
2551
2552 redo:
2553 switch(ch) {
2554 case ' ':
2555 case '\t':
2556 case '\f':
2557 case '\v':
2558 case '\r':
2559 case '\n':
2560 inp();
2561 goto redo;
2562 case '/':
2563 minp();
2564 if (ch == '*') {
2565 file->buf_ptr = parse_comment(file->buf_ptr);
2566 ch = file->buf_ptr[0];
2567 goto redo;
2568 } else {
2569 q = name;
2570 *q++ = '/';
2571 goto parse_name;
2572 }
2573 break;
2574 /* case 'a' ... 'z': */
2575 case 'a':
2576 case 'b':
2577 case 'c':
2578 case 'd':
2579 case 'e':
2580 case 'f':
2581 case 'g':
2582 case 'h':
2583 case 'i':
2584 case 'j':
2585 case 'k':
2586 case 'l':
2587 case 'm':
2588 case 'n':
2589 case 'o':
2590 case 'p':
2591 case 'q':
2592 case 'r':
2593 case 's':
2594 case 't':
2595 case 'u':
2596 case 'v':
2597 case 'w':
2598 case 'x':
2599 case 'y':
2600 case 'z':
2601 /* case 'A' ... 'z': */
2602 case 'A':
2603 case 'B':
2604 case 'C':
2605 case 'D':
2606 case 'E':
2607 case 'F':
2608 case 'G':
2609 case 'H':
2610 case 'I':
2611 case 'J':
2612 case 'K':
2613 case 'L':
2614 case 'M':
2615 case 'N':
2616 case 'O':
2617 case 'P':
2618 case 'Q':
2619 case 'R':
2620 case 'S':
2621 case 'T':
2622 case 'U':
2623 case 'V':
2624 case 'W':
2625 case 'X':
2626 case 'Y':
2627 case 'Z':
2628 case '_':
2629 case '\\':
2630 case '.':
2631 case '$':
2632 case '~':
2633 q = name;
2634 parse_name:
2635 for(;;) {
2636 if (!((ch >= 'a' && ch <= 'z') ||
2637 (ch >= 'A' && ch <= 'Z') ||
2638 (ch >= '0' && ch <= '9') ||
2639 strchr("/.-_+=$:\\,~", ch)))
2640 break;
2641 if ((q - name) < name_size - 1) {
2642 *q++ = ch;
2643 }
2644 minp();
2645 }
2646 *q = '\0';
2647 c = LD_TOK_NAME;
2648 break;
2649 case CH_EOF:
2650 c = LD_TOK_EOF;
2651 break;
2652 default:
2653 c = ch;
2654 inp();
2655 break;
2656 }
2657 #if 0
2658 printf("tok=%c %d\n", c, c);
2659 if (c == LD_TOK_NAME)
2660 printf(" name=%s\n", name);
2661 #endif
2662 return c;
2663 }
2664
2665 static int ld_add_file_list(TCCState *s1, int as_needed)
2666 {
2667 char filename[1024];
2668 int t, ret;
2669
2670 t = ld_next(s1, filename, sizeof(filename));
2671 if (t != '(')
2672 expect("(");
2673 t = ld_next(s1, filename, sizeof(filename));
2674 for(;;) {
2675 if (t == LD_TOK_EOF) {
2676 error_noabort("unexpected end of file");
2677 return -1;
2678 } else if (t == ')') {
2679 break;
2680 } else if (t != LD_TOK_NAME) {
2681 error_noabort("filename expected");
2682 return -1;
2683 }
2684 if (!strcmp(filename, "AS_NEEDED")) {
2685 ret = ld_add_file_list(s1, 1);
2686 if (ret)
2687 return ret;
2688 } else {
2689 /* TODO: Implement AS_NEEDED support. Ignore it for now */
2690 if (!as_needed)
2691 tcc_add_file(s1, filename);
2692 }
2693 t = ld_next(s1, filename, sizeof(filename));
2694 if (t == ',') {
2695 t = ld_next(s1, filename, sizeof(filename));
2696 }
2697 }
2698 return 0;
2699 }
2700
2701 /* interpret a subset of GNU ldscripts to handle the dummy libc.so
2702 files */
2703 static int tcc_load_ldscript(TCCState *s1)
2704 {
2705 char cmd[64];
2706 char filename[1024];
2707 int t, ret;
2708
2709 ch = file->buf_ptr[0];
2710 ch = handle_eob();
2711 for(;;) {
2712 t = ld_next(s1, cmd, sizeof(cmd));
2713 if (t == LD_TOK_EOF)
2714 return 0;
2715 else if (t != LD_TOK_NAME)
2716 return -1;
2717 if (!strcmp(cmd, "INPUT") ||
2718 !strcmp(cmd, "GROUP")) {
2719 ret = ld_add_file_list(s1, 0);
2720 if (ret)
2721 return ret;
2722 } else if (!strcmp(cmd, "OUTPUT_FORMAT") ||
2723 !strcmp(cmd, "TARGET")) {
2724 /* ignore some commands */
2725 t = ld_next(s1, cmd, sizeof(cmd));
2726 if (t != '(')
2727 expect("(");
2728 for(;;) {
2729 t = ld_next(s1, filename, sizeof(filename));
2730 if (t == LD_TOK_EOF) {
2731 error_noabort("unexpected end of file");
2732 return -1;
2733 } else if (t == ')') {
2734 break;
2735 }
2736 }
2737 } else {
2738 return -1;
2739 }
2740 }
2741 return 0;
2742 }
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