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Def signedness != signed != unsigned for char
[tinycc.git] / tccelf.c
blobbae8972d86628e41c12f3a789bc96f4d56ec36ee
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 #include "tcc.h"
22
23 /* XXX: avoid static variable */
24 static int new_undef_sym = 0; /* Is there a new undefined sym since last new_undef_sym() */
25
26 ST_FUNC int put_elf_str(Section *s, const char *sym)
27 {
28 int offset, len;
29 char *ptr;
30
31 len = strlen(sym) + 1;
32 offset = s->data_offset;
33 ptr = section_ptr_add(s, len);
34 memcpy(ptr, sym, len);
35 return offset;
36 }
37
38 /* elf symbol hashing function */
39 static unsigned long elf_hash(const unsigned char *name)
40 {
41 unsigned long h = 0, g;
42
43 while (*name) {
44 h = (h << 4) + *name++;
45 g = h & 0xf0000000;
46 if (g)
47 h ^= g >> 24;
48 h &= ~g;
49 }
50 return h;
51 }
52
53 /* rebuild hash table of section s */
54 /* NOTE: we do factorize the hash table code to go faster */
55 static void rebuild_hash(Section *s, unsigned int nb_buckets)
56 {
57 ElfW(Sym) *sym;
58 int *ptr, *hash, nb_syms, sym_index, h;
59 char *strtab;
60
61 strtab = s->link->data;
62 nb_syms = s->data_offset / sizeof(ElfW(Sym));
63
64 s->hash->data_offset = 0;
65 ptr = section_ptr_add(s->hash, (2 + nb_buckets + nb_syms) * sizeof(int));
66 ptr[0] = nb_buckets;
67 ptr[1] = nb_syms;
68 ptr += 2;
69 hash = ptr;
70 memset(hash, 0, (nb_buckets + 1) * sizeof(int));
71 ptr += nb_buckets + 1;
72
73 sym = (ElfW(Sym) *)s->data + 1;
74 for(sym_index = 1; sym_index < nb_syms; sym_index++) {
75 if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
76 h = elf_hash(strtab + sym->st_name) % nb_buckets;
77 *ptr = hash[h];
78 hash[h] = sym_index;
79 } else {
80 *ptr = 0;
81 }
82 ptr++;
83 sym++;
84 }
85 }
86
87 /* return the symbol number */
88 ST_FUNC int put_elf_sym(Section *s, addr_t value, unsigned long size,
89 int info, int other, int shndx, const char *name)
90 {
91 int name_offset, sym_index;
92 int nbuckets, h;
93 ElfW(Sym) *sym;
94 Section *hs;
95
96 sym = section_ptr_add(s, sizeof(ElfW(Sym)));
97 if (name)
98 name_offset = put_elf_str(s->link, name);
99 else
100 name_offset = 0;
101 /* XXX: endianness */
102 sym->st_name = name_offset;
103 sym->st_value = value;
104 sym->st_size = size;
105 sym->st_info = info;
106 sym->st_other = other;
107 sym->st_shndx = shndx;
108 sym_index = sym - (ElfW(Sym) *)s->data;
109 hs = s->hash;
110 if (hs) {
111 int *ptr, *base;
112 ptr = section_ptr_add(hs, sizeof(int));
113 base = (int *)hs->data;
114 /* only add global or weak symbols */
115 if (ELFW(ST_BIND)(info) != STB_LOCAL) {
116 /* add another hashing entry */
117 nbuckets = base[0];
118 h = elf_hash(name) % nbuckets;
119 *ptr = base[2 + h];
120 base[2 + h] = sym_index;
121 base[1]++;
122 /* we resize the hash table */
123 hs->nb_hashed_syms++;
124 if (hs->nb_hashed_syms > 2 * nbuckets) {
125 rebuild_hash(s, 2 * nbuckets);
126 }
127 } else {
128 *ptr = 0;
129 base[1]++;
130 }
131 }
132 return sym_index;
133 }
134
135 /* find global ELF symbol 'name' and return its index. Return 0 if not
136 found. */
137 ST_FUNC int find_elf_sym(Section *s, const char *name)
138 {
139 ElfW(Sym) *sym;
140 Section *hs;
141 int nbuckets, sym_index, h;
142 const char *name1;
143
144 hs = s->hash;
145 if (!hs)
146 return 0;
147 nbuckets = ((int *)hs->data)[0];
148 h = elf_hash(name) % nbuckets;
149 sym_index = ((int *)hs->data)[2 + h];
150 while (sym_index != 0) {
151 sym = &((ElfW(Sym) *)s->data)[sym_index];
152 name1 = s->link->data + sym->st_name;
153 if (!strcmp(name, name1))
154 return sym_index;
155 sym_index = ((int *)hs->data)[2 + nbuckets + sym_index];
156 }
157 return 0;
158 }
159
160 /* return elf symbol value, signal error if 'err' is nonzero */
161 ST_FUNC addr_t get_elf_sym_addr(TCCState *s, const char *name, int err)
162 {
163 int sym_index;
164 ElfW(Sym) *sym;
165
166 sym_index = find_elf_sym(s->symtab, name);
167 sym = &((ElfW(Sym) *)s->symtab->data)[sym_index];
168 if (!sym_index || sym->st_shndx == SHN_UNDEF) {
169 if (err)
170 tcc_error("%s not defined", name);
171 return 0;
172 }
173 return sym->st_value;
174 }
175
176 /* return elf symbol value */
177 LIBTCCAPI void *tcc_get_symbol(TCCState *s, const char *name)
178 {
179 return (void*)(uintptr_t)get_elf_sym_addr(s, name, 0);
180 }
181
182 #if defined TCC_IS_NATIVE || defined TCC_TARGET_PE
183 /* return elf symbol value or error */
184 ST_FUNC void* tcc_get_symbol_err(TCCState *s, const char *name)
185 {
186 return (void*)(uintptr_t)get_elf_sym_addr(s, name, 1);
187 }
188 #endif
189
190 /* add an elf symbol : check if it is already defined and patch
191 it. Return symbol index. NOTE that sh_num can be SHN_UNDEF. */
192 ST_FUNC int add_elf_sym(Section *s, addr_t value, unsigned long size,
193 int info, int other, int sh_num, const char *name)
194 {
195 ElfW(Sym) *esym;
196 int sym_bind, sym_index, sym_type, esym_bind;
197 unsigned char sym_vis, esym_vis, new_vis;
198
199 sym_bind = ELFW(ST_BIND)(info);
200 sym_type = ELFW(ST_TYPE)(info);
201 sym_vis = ELFW(ST_VISIBILITY)(other);
202
203 if (sym_bind != STB_LOCAL) {
204 /* we search global or weak symbols */
205 sym_index = find_elf_sym(s, name);
206 if (!sym_index)
207 goto do_def;
208 esym = &((ElfW(Sym) *)s->data)[sym_index];
209 if (esym->st_shndx != SHN_UNDEF) {
210 esym_bind = ELFW(ST_BIND)(esym->st_info);
211 /* propagate the most constraining visibility */
212 /* STV_DEFAULT(0)<STV_PROTECTED(3)<STV_HIDDEN(2)<STV_INTERNAL(1) */
213 esym_vis = ELFW(ST_VISIBILITY)(esym->st_other);
214 if (esym_vis == STV_DEFAULT) {
215 new_vis = sym_vis;
216 } else if (sym_vis == STV_DEFAULT) {
217 new_vis = esym_vis;
218 } else {
219 new_vis = (esym_vis < sym_vis) ? esym_vis : sym_vis;
220 }
221 esym->st_other = (esym->st_other & ~ELFW(ST_VISIBILITY)(-1))
222 | new_vis;
223 other = esym->st_other; /* in case we have to patch esym */
224 if (sh_num == SHN_UNDEF) {
225 /* ignore adding of undefined symbol if the
226 corresponding symbol is already defined */
227 } else if (sym_bind == STB_GLOBAL && esym_bind == STB_WEAK) {
228 /* global overrides weak, so patch */
229 goto do_patch;
230 } else if (sym_bind == STB_WEAK && esym_bind == STB_GLOBAL) {
231 /* weak is ignored if already global */
232 } else if (sym_bind == STB_WEAK && esym_bind == STB_WEAK) {
233 /* keep first-found weak definition, ignore subsequents */
234 } else if (sym_vis == STV_HIDDEN || sym_vis == STV_INTERNAL) {
235 /* ignore hidden symbols after */
236 } else if (esym->st_shndx == SHN_COMMON
237 && (sh_num < SHN_LORESERVE || sh_num == SHN_COMMON)) {
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 0
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 tcc_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 new_undef_sym = 1;
255 esym->st_value = value;
256 esym->st_size = size;
257 esym->st_other = other;
258 }
259 } else {
260 do_def:
261 sym_index = put_elf_sym(s, value, size,
262 ELFW(ST_INFO)(sym_bind, sym_type), other,
263 sh_num, name);
264 }
265 return sym_index;
266 }
267
268 /* put relocation */
269 ST_FUNC void put_elf_reloc(Section *symtab, Section *s, unsigned long offset,
270 int type, int symbol)
271 {
272 char buf[256];
273 Section *sr;
274 ElfW_Rel *rel;
275
276 sr = s->reloc;
277 if (!sr) {
278 /* if no relocation section, create it */
279 snprintf(buf, sizeof(buf), REL_SECTION_FMT, s->name);
280 /* if the symtab is allocated, then we consider the relocation
281 are also */
282 sr = new_section(tcc_state, buf, SHT_RELX, symtab->sh_flags);
283 sr->sh_entsize = sizeof(ElfW_Rel);
284 sr->link = symtab;
285 sr->sh_info = s->sh_num;
286 s->reloc = sr;
287 }
288 rel = section_ptr_add(sr, sizeof(ElfW_Rel));
289 rel->r_offset = offset;
290 rel->r_info = ELFW(R_INFO)(symbol, type);
291 #ifdef TCC_TARGET_X86_64
292 rel->r_addend = 0;
293 #endif
294 }
295
296 /* put stab debug information */
297
298 ST_FUNC void put_stabs(const char *str, int type, int other, int desc,
299 unsigned long value)
300 {
301 Stab_Sym *sym;
302
303 sym = section_ptr_add(stab_section, sizeof(Stab_Sym));
304 if (str) {
305 sym->n_strx = put_elf_str(stabstr_section, str);
306 } else {
307 sym->n_strx = 0;
308 }
309 sym->n_type = type;
310 sym->n_other = other;
311 sym->n_desc = desc;
312 sym->n_value = value;
313 }
314
315 ST_FUNC void put_stabs_r(const char *str, int type, int other, int desc,
316 unsigned long value, Section *sec, int sym_index)
317 {
318 put_stabs(str, type, other, desc, value);
319 put_elf_reloc(symtab_section, stab_section,
320 stab_section->data_offset - sizeof(unsigned int),
321 R_DATA_32, sym_index);
322 }
323
324 ST_FUNC void put_stabn(int type, int other, int desc, int value)
325 {
326 put_stabs(NULL, type, other, desc, value);
327 }
328
329 ST_FUNC void put_stabd(int type, int other, int desc)
330 {
331 put_stabs(NULL, type, other, desc, 0);
332 }
333
334 /* Browse each elem of type <type> in section <sec> starting at elem <startoff>
335 using variable <elem> */
336 #define for_each_elem(sec, startoff, elem, type) \
337 for (elem = (type *) sec->data + startoff; \
338 elem < (type *) (sec->data + sec->data_offset); elem++)
339
340 /* In an ELF file symbol table, the local symbols must appear below
341 the global and weak ones. Since TCC cannot sort it while generating
342 the code, we must do it after. All the relocation tables are also
343 modified to take into account the symbol table sorting */
344 static void sort_syms(TCCState *s1, Section *s)
345 {
346 int *old_to_new_syms;
347 ElfW(Sym) *new_syms;
348 int nb_syms, i;
349 ElfW(Sym) *p, *q;
350 ElfW_Rel *rel;
351 Section *sr;
352 int type, sym_index;
353
354 nb_syms = s->data_offset / sizeof(ElfW(Sym));
355 new_syms = tcc_malloc(nb_syms * sizeof(ElfW(Sym)));
356 old_to_new_syms = tcc_malloc(nb_syms * sizeof(int));
357
358 /* first pass for local symbols */
359 p = (ElfW(Sym) *)s->data;
360 q = new_syms;
361 for(i = 0; i < nb_syms; i++) {
362 if (ELFW(ST_BIND)(p->st_info) == STB_LOCAL) {
363 old_to_new_syms[i] = q - new_syms;
364 *q++ = *p;
365 }
366 p++;
367 }
368 /* save the number of local symbols in section header */
369 s->sh_info = q - new_syms;
370
371 /* then second pass for non local symbols */
372 p = (ElfW(Sym) *)s->data;
373 for(i = 0; i < nb_syms; i++) {
374 if (ELFW(ST_BIND)(p->st_info) != STB_LOCAL) {
375 old_to_new_syms[i] = q - new_syms;
376 *q++ = *p;
377 }
378 p++;
379 }
380
381 /* we copy the new symbols to the old */
382 memcpy(s->data, new_syms, nb_syms * sizeof(ElfW(Sym)));
383 tcc_free(new_syms);
384
385 /* now we modify all the relocations */
386 for(i = 1; i < s1->nb_sections; i++) {
387 sr = s1->sections[i];
388 if (sr->sh_type == SHT_RELX && sr->link == s) {
389 for_each_elem(sr, 0, rel, ElfW_Rel) {
390 sym_index = ELFW(R_SYM)(rel->r_info);
391 type = ELFW(R_TYPE)(rel->r_info);
392 sym_index = old_to_new_syms[sym_index];
393 rel->r_info = ELFW(R_INFO)(sym_index, type);
394 }
395 }
396 }
397
398 tcc_free(old_to_new_syms);
399 }
400
401 /* relocate common symbols in the .bss section */
402 ST_FUNC void relocate_common_syms(void)
403 {
404 ElfW(Sym) *sym;
405 unsigned long offset, align;
406
407 for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
408 if (sym->st_shndx == SHN_COMMON) {
409 /* align symbol */
410 align = sym->st_value;
411 offset = bss_section->data_offset;
412 offset = (offset + align - 1) & -align;
413 sym->st_value = offset;
414 sym->st_shndx = bss_section->sh_num;
415 offset += sym->st_size;
416 bss_section->data_offset = offset;
417 }
418 }
419 }
420
421 /* relocate symbol table, resolve undefined symbols if do_resolve is
422 true and output error if undefined symbol. */
423 ST_FUNC void relocate_syms(TCCState *s1, int do_resolve)
424 {
425 ElfW(Sym) *sym, *esym;
426 int sym_bind, sh_num, sym_index;
427 const char *name;
428
429 for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
430 sh_num = sym->st_shndx;
431 if (sh_num == SHN_UNDEF) {
432 name = strtab_section->data + sym->st_name;
433 /* Use ld.so to resolve symbol for us (for tcc -run) */
434 if (do_resolve) {
435 #if defined TCC_IS_NATIVE && !defined _WIN32
436 void *addr;
437 name = symtab_section->link->data + sym->st_name;
438 addr = resolve_sym(s1, name);
439 if (addr) {
440 sym->st_value = (addr_t)addr;
441 goto found;
442 }
443 #endif
444 } else if (s1->dynsym) {
445 /* if dynamic symbol exist, then use it */
446 sym_index = find_elf_sym(s1->dynsym, name);
447 if (sym_index) {
448 esym = &((ElfW(Sym) *)s1->dynsym->data)[sym_index];
449 sym->st_value = esym->st_value;
450 goto found;
451 }
452 }
453 /* XXX: _fp_hw seems to be part of the ABI, so we ignore
454 it */
455 if (!strcmp(name, "_fp_hw"))
456 goto found;
457 /* only weak symbols are accepted to be undefined. Their
458 value is zero */
459 sym_bind = ELFW(ST_BIND)(sym->st_info);
460 if (sym_bind == STB_WEAK) {
461 sym->st_value = 0;
462 } else {
463 tcc_error_noabort("undefined symbol '%s'", name);
464 }
465 } else if (sh_num < SHN_LORESERVE) {
466 /* add section base */
467 sym->st_value += s1->sections[sym->st_shndx]->sh_addr;
468 }
469 found: ;
470 }
471 }
472
473 #ifdef TCC_HAS_RUNTIME_PLTGOT
474 #ifdef TCC_TARGET_X86_64
475 #define JMP_TABLE_ENTRY_SIZE 14
476 static addr_t add_jmp_table(TCCState *s1, addr_t val)
477 {
478 char *p = s1->runtime_plt_and_got + s1->runtime_plt_and_got_offset;
479 s1->runtime_plt_and_got_offset += JMP_TABLE_ENTRY_SIZE;
480 /* jmp *0x0(%rip) */
481 p[0] = 0xff;
482 p[1] = 0x25;
483 *(int *)(p + 2) = 0;
484 *(addr_t *)(p + 6) = val;
485 return (addr_t)p;
486 }
487
488 static addr_t add_got_table(TCCState *s1, addr_t val)
489 {
490 addr_t *p = (addr_t *)(s1->runtime_plt_and_got + s1->runtime_plt_and_got_offset);
491 s1->runtime_plt_and_got_offset += sizeof(addr_t);
492 *p = val;
493 return (addr_t)p;
494 }
495 #elif defined TCC_TARGET_ARM
496 #define JMP_TABLE_ENTRY_SIZE 8
497 static addr_t add_jmp_table(TCCState *s1, int val)
498 {
499 uint32_t *p = (uint32_t *)(s1->runtime_plt_and_got + s1->runtime_plt_and_got_offset);
500 s1->runtime_plt_and_got_offset += JMP_TABLE_ENTRY_SIZE;
501 /* ldr pc, [pc, #-4] */
502 p[0] = 0xE51FF004;
503 p[1] = val;
504 return (addr_t)p;
505 }
506 #endif
507 #endif /* def TCC_HAS_RUNTIME_PLTGOT */
508
509 /* relocate a given section (CPU dependent) by applying the relocations
510 in the associated relocation section */
511 ST_FUNC void relocate_section(TCCState *s1, Section *s)
512 {
513 Section *sr = s->reloc;
514 ElfW_Rel *rel;
515 ElfW(Sym) *sym;
516 int type, sym_index;
517 unsigned char *ptr;
518 addr_t val, addr;
519 #if defined TCC_TARGET_I386 || defined TCC_TARGET_X86_64
520 ElfW_Rel *qrel = (ElfW_Rel *) sr->data; /* ptr to next reloc entry reused */
521 int esym_index;
522 #endif
523
524 for_each_elem(sr, 0, rel, ElfW_Rel) {
525 ptr = s->data + rel->r_offset;
526
527 sym_index = ELFW(R_SYM)(rel->r_info);
528 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
529 val = sym->st_value;
530 #ifdef TCC_TARGET_X86_64
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->sym_attrs[sym_index].got_offset;
583 break;
584 case R_386_16:
585 if (s1->output_format != TCC_OUTPUT_FORMAT_BINARY) {
586 output_file:
587 tcc_error("can only produce 16-bit binary files");
588 }
589 *(short *)ptr += val;
590 break;
591 case R_386_PC16:
592 if (s1->output_format != TCC_OUTPUT_FORMAT_BINARY)
593 goto output_file;
594 *(short *)ptr += val - addr;
595 break;
596 #elif defined(TCC_TARGET_ARM)
597 case R_ARM_PC24:
598 case R_ARM_CALL:
599 case R_ARM_JUMP24:
600 case R_ARM_PLT32:
601 {
602 int x, is_thumb, is_call, h, blx_avail, is_bl, th_ko;
603 x = (*(int *) ptr) & 0xffffff;
604 (*(int *)ptr) &= 0xff000000;
605 if (x & 0x800000)
606 x -= 0x1000000;
607 x <<= 2;
608 blx_avail = (TCC_ARM_VERSION >= 5);
609 is_thumb = val & 1;
610 is_bl = (*(unsigned *) ptr) >> 24 == 0xeb;
611 is_call = (type == R_ARM_CALL || (type == R_ARM_PC24 && is_bl));
612 x += val - addr;
613 h = x & 2;
614 th_ko = (x & 3) && (!blx_avail || !is_call);
615 #ifdef TCC_HAS_RUNTIME_PLTGOT
616 if (s1->output_type == TCC_OUTPUT_MEMORY) {
617 if (th_ko || x >= 0x2000000 || x < -0x2000000) {
618 x += add_jmp_table(s1, val) - val; /* add veneer */
619 th_ko = (x & 3) && (!blx_avail || !is_call);
620 is_thumb = 0; /* Veneer uses ARM instructions */
621 }
622 }
623 #endif
624 if (th_ko || x >= 0x2000000 || x < -0x2000000)
625 tcc_error("can't relocate value at %x",addr);
626 x >>= 2;
627 x &= 0xffffff;
628 /* Only reached if blx is avail and it is a call */
629 if (is_thumb) {
630 x |= h << 24;
631 (*(int *)ptr) = 0xfa << 24; /* bl -> blx */
632 }
633 (*(int *) ptr) |= x;
634 }
635 break;
636 /* Since these relocations only concern Thumb-2 and blx instruction was
637 introduced before Thumb-2, we can assume blx is available and not
638 guard its use */
639 case R_ARM_THM_PC22:
640 case R_ARM_THM_JUMP24:
641 {
642 int x, hi, lo, s, j1, j2, i1, i2, imm10, imm11;
643 int to_thumb, is_call, to_plt, blx_bit = 1 << 12;
644 Section *plt;
645
646 /* weak reference */
647 if (sym->st_shndx == SHN_UNDEF &&
648 ELFW(ST_BIND)(sym->st_info) == STB_WEAK)
649 break;
650
651 /* Get initial offset */
652 hi = (*(uint16_t *)ptr);
653 lo = (*(uint16_t *)(ptr+2));
654 s = (hi >> 10) & 1;
655 j1 = (lo >> 13) & 1;
656 j2 = (lo >> 11) & 1;
657 i1 = (j1 ^ s) ^ 1;
658 i2 = (j2 ^ s) ^ 1;
659 imm10 = hi & 0x3ff;
660 imm11 = lo & 0x7ff;
661 x = (s << 24) | (i1 << 23) | (i2 << 22) |
662 (imm10 << 12) | (imm11 << 1);
663 if (x & 0x01000000)
664 x -= 0x02000000;
665
666 /* Relocation infos */
667 to_thumb = val & 1;
668 plt = s1->plt;
669 to_plt = (val >= plt->sh_addr) &&
670 (val < plt->sh_addr + plt->data_offset);
671 is_call = (type == R_ARM_THM_PC22);
672
673 /* Compute final offset */
674 if (to_plt && !is_call) /* Point to 1st instr of Thumb stub */
675 x -= 4;
676 x += val - addr;
677 if (!to_thumb && is_call) {
678 blx_bit = 0; /* bl -> blx */
679 x = (x + 3) & -4; /* Compute offset from aligned PC */
680 }
681
682 /* Check that relocation is possible
683 * offset must not be out of range
684 * if target is to be entered in arm mode:
685 - bit 1 must not set
686 - instruction must be a call (bl) or a jump to PLT */
687 if (!to_thumb || x >= 0x1000000 || x < -0x1000000)
688 if (to_thumb || (val & 2) || (!is_call && !to_plt))
689 tcc_error("can't relocate value at %x",addr);
690
691 /* Compute and store final offset */
692 s = (x >> 24) & 1;
693 i1 = (x >> 23) & 1;
694 i2 = (x >> 22) & 1;
695 j1 = s ^ (i1 ^ 1);
696 j2 = s ^ (i2 ^ 1);
697 imm10 = (x >> 12) & 0x3ff;
698 imm11 = (x >> 1) & 0x7ff;
699 (*(uint16_t *)ptr) = (uint16_t) ((hi & 0xf800) |
700 (s << 10) | imm10);
701 (*(uint16_t *)(ptr+2)) = (uint16_t) ((lo & 0xc000) |
702 (j1 << 13) | blx_bit | (j2 << 11) |
703 imm11);
704 }
705 break;
706 case R_ARM_MOVT_ABS:
707 case R_ARM_MOVW_ABS_NC:
708 {
709 int x, imm4, imm12;
710 if (type == R_ARM_MOVT_ABS)
711 val >>= 16;
712 imm12 = val & 0xfff;
713 imm4 = (val >> 12) & 0xf;
714 x = (imm4 << 16) | imm12;
715 if (type == R_ARM_THM_MOVT_ABS)
716 *(int *)ptr |= x;
717 else
718 *(int *)ptr += x;
719 }
720 break;
721 case R_ARM_THM_MOVT_ABS:
722 case R_ARM_THM_MOVW_ABS_NC:
723 {
724 int x, i, imm4, imm3, imm8;
725 if (type == R_ARM_THM_MOVT_ABS)
726 val >>= 16;
727 imm8 = val & 0xff;
728 imm3 = (val >> 8) & 0x7;
729 i = (val >> 11) & 1;
730 imm4 = (val >> 12) & 0xf;
731 x = (imm3 << 28) | (imm8 << 16) | (i << 10) | imm4;
732 if (type == R_ARM_THM_MOVT_ABS)
733 *(int *)ptr |= x;
734 else
735 *(int *)ptr += x;
736 }
737 break;
738 case R_ARM_PREL31:
739 {
740 int x;
741 x = (*(int *)ptr) & 0x7fffffff;
742 (*(int *)ptr) &= 0x80000000;
743 x = (x * 2) / 2;
744 x += val - addr;
745 if((x^(x>>1))&0x40000000)
746 tcc_error("can't relocate value at %x",addr);
747 (*(int *)ptr) |= x & 0x7fffffff;
748 }
749 case R_ARM_ABS32:
750 *(int *)ptr += val;
751 break;
752 case R_ARM_REL32:
753 *(int *)ptr += val - addr;
754 break;
755 case R_ARM_GOTPC:
756 *(int *)ptr += s1->got->sh_addr - addr;
757 break;
758 case R_ARM_GOTOFF:
759 *(int *)ptr += val - s1->got->sh_addr;
760 break;
761 case R_ARM_GOT32:
762 /* we load the got offset */
763 *(int *)ptr += s1->sym_attrs[sym_index].got_offset;
764 break;
765 case R_ARM_COPY:
766 break;
767 case R_ARM_V4BX:
768 /* trade Thumb support for ARMv4 support */
769 if ((0x0ffffff0 & *(int*)ptr) == 0x012FFF10)
770 *(int*)ptr ^= 0xE12FFF10 ^ 0xE1A0F000; /* BX Rm -> MOV PC, Rm */
771 break;
772 default:
773 fprintf(stderr,"FIXME: handle reloc type %x at %x [%p] to %x\n",
774 type, (unsigned)addr, ptr, (unsigned)val);
775 break;
776 #elif defined(TCC_TARGET_C67)
777 case R_C60_32:
778 *(int *)ptr += val;
779 break;
780 case R_C60LO16:
781 {
782 uint32_t orig;
783
784 /* put the low 16 bits of the absolute address
785 add to what is already there */
786
787 orig = ((*(int *)(ptr )) >> 7) & 0xffff;
788 orig |= (((*(int *)(ptr+4)) >> 7) & 0xffff) << 16;
789
790 /* patch both at once - assumes always in pairs Low - High */
791
792 *(int *) ptr = (*(int *) ptr & (~(0xffff << 7)) ) | (((val+orig) & 0xffff) << 7);
793 *(int *)(ptr+4) = (*(int *)(ptr+4) & (~(0xffff << 7)) ) | ((((val+orig)>>16) & 0xffff) << 7);
794 }
795 break;
796 case R_C60HI16:
797 break;
798 default:
799 fprintf(stderr,"FIXME: handle reloc type %x at %x [%p] to %x\n",
800 type, (unsigned)addr, ptr, (unsigned)val);
801 break;
802 #elif defined(TCC_TARGET_X86_64)
803 case R_X86_64_64:
804 if (s1->output_type == TCC_OUTPUT_DLL) {
805 qrel->r_info = ELFW(R_INFO)(0, R_X86_64_RELATIVE);
806 qrel->r_addend = *(long long *)ptr + val;
807 qrel++;
808 }
809 *(long long *)ptr += val;
810 break;
811 case R_X86_64_32:
812 case R_X86_64_32S:
813 if (s1->output_type == TCC_OUTPUT_DLL) {
814 /* XXX: this logic may depend on TCC's codegen
815 now TCC uses R_X86_64_32 even for a 64bit pointer */
816 qrel->r_info = ELFW(R_INFO)(0, R_X86_64_RELATIVE);
817 qrel->r_addend = *(int *)ptr + val;
818 qrel++;
819 }
820 *(int *)ptr += val;
821 break;
822
823 case R_X86_64_PC32:
824 if (s1->output_type == TCC_OUTPUT_DLL) {
825 /* DLL relocation */
826 esym_index = s1->symtab_to_dynsym[sym_index];
827 if (esym_index) {
828 qrel->r_offset = rel->r_offset;
829 qrel->r_info = ELFW(R_INFO)(esym_index, R_X86_64_PC32);
830 qrel->r_addend = *(int *)ptr;
831 qrel++;
832 break;
833 }
834 }
835 /* fall through */
836 case R_X86_64_PLT32: {
837 long long diff;
838 diff = (long long)val - addr;
839 if (diff <= -2147483647 || diff > 2147483647) {
840 #ifdef TCC_HAS_RUNTIME_PLTGOT
841 /* XXX: naive support for over 32bit jump */
842 if (s1->output_type == TCC_OUTPUT_MEMORY) {
843 val = (add_jmp_table(s1, val - rel->r_addend) +
844 rel->r_addend);
845 diff = val - addr;
846 }
847 #endif
848 if (diff <= -2147483647 || diff > 2147483647) {
849 tcc_error("internal error: relocation failed");
850 }
851 }
852 *(int *)ptr += diff;
853 }
854 break;
855 case R_X86_64_GLOB_DAT:
856 case R_X86_64_JUMP_SLOT:
857 /* They don't need addend */
858 *(int *)ptr = val - rel->r_addend;
859 break;
860 case R_X86_64_GOTPCREL:
861 #ifdef TCC_HAS_RUNTIME_PLTGOT
862 if (s1->output_type == TCC_OUTPUT_MEMORY) {
863 val = add_got_table(s1, val - rel->r_addend) + rel->r_addend;
864 *(int *)ptr += val - addr;
865 break;
866 }
867 #endif
868 *(int *)ptr += (s1->got->sh_addr - addr +
869 s1->sym_attrs[sym_index].got_offset - 4);
870 break;
871 case R_X86_64_GOTTPOFF:
872 *(int *)ptr += val - s1->got->sh_addr;
873 break;
874 case R_X86_64_GOT32:
875 /* we load the got offset */
876 *(int *)ptr += s1->sym_attrs[sym_index].got_offset;
877 break;
878 #else
879 #error unsupported processor
880 #endif
881 }
882 }
883 /* if the relocation is allocated, we change its symbol table */
884 if (sr->sh_flags & SHF_ALLOC)
885 sr->link = s1->dynsym;
886 }
887
888 /* relocate relocation table in 'sr' */
889 static void relocate_rel(TCCState *s1, Section *sr)
890 {
891 Section *s;
892 ElfW_Rel *rel;
893
894 s = s1->sections[sr->sh_info];
895 for_each_elem(sr, 0, rel, ElfW_Rel)
896 rel->r_offset += s->sh_addr;
897 }
898
899 /* count the number of dynamic relocations so that we can reserve
900 their space */
901 static int prepare_dynamic_rel(TCCState *s1, Section *sr)
902 {
903 ElfW_Rel *rel;
904 int sym_index, esym_index, type, count;
905
906 count = 0;
907 for_each_elem(sr, 0, rel, ElfW_Rel) {
908 sym_index = ELFW(R_SYM)(rel->r_info);
909 type = ELFW(R_TYPE)(rel->r_info);
910 switch(type) {
911 #if defined(TCC_TARGET_I386)
912 case R_386_32:
913 #elif defined(TCC_TARGET_X86_64)
914 case R_X86_64_32:
915 case R_X86_64_32S:
916 case R_X86_64_64:
917 #endif
918 count++;
919 break;
920 #if defined(TCC_TARGET_I386)
921 case R_386_PC32:
922 #elif defined(TCC_TARGET_X86_64)
923 case R_X86_64_PC32:
924 #endif
925 esym_index = s1->symtab_to_dynsym[sym_index];
926 if (esym_index)
927 count++;
928 break;
929 default:
930 break;
931 }
932 }
933 if (count) {
934 /* allocate the section */
935 sr->sh_flags |= SHF_ALLOC;
936 sr->sh_size = count * sizeof(ElfW_Rel);
937 }
938 return count;
939 }
940
941 static struct sym_attr *alloc_sym_attr(TCCState *s1, int index)
942 {
943 int n;
944 struct sym_attr *tab;
945
946 if (index >= s1->nb_sym_attrs) {
947 /* find immediately bigger power of 2 and reallocate array */
948 n = 1;
949 while (index >= n)
950 n *= 2;
951 tab = tcc_realloc(s1->sym_attrs, n * sizeof(*s1->sym_attrs));
952 s1->sym_attrs = tab;
953 memset(s1->sym_attrs + s1->nb_sym_attrs, 0,
954 (n - s1->nb_sym_attrs) * sizeof(*s1->sym_attrs));
955 s1->nb_sym_attrs = n;
956 }
957 return &s1->sym_attrs[index];
958 }
959
960 /* XXX: suppress that */
961 static void put32(unsigned char *p, uint32_t val)
962 {
963 p[0] = val;
964 p[1] = val >> 8;
965 p[2] = val >> 16;
966 p[3] = val >> 24;
967 }
968
969 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_ARM) || \
970 defined(TCC_TARGET_X86_64)
971 static uint32_t get32(unsigned char *p)
972 {
973 return p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);
974 }
975 #endif
976
977 static void build_got(TCCState *s1)
978 {
979 unsigned char *ptr;
980
981 /* if no got, then create it */
982 s1->got = new_section(s1, ".got", SHT_PROGBITS, SHF_ALLOC | SHF_WRITE);
983 s1->got->sh_entsize = 4;
984 add_elf_sym(symtab_section, 0, 4, ELFW(ST_INFO)(STB_GLOBAL, STT_OBJECT),
985 0, s1->got->sh_num, "_GLOBAL_OFFSET_TABLE_");
986 ptr = section_ptr_add(s1->got, 3 * PTR_SIZE);
987 #if PTR_SIZE == 4
988 /* keep space for _DYNAMIC pointer, if present */
989 put32(ptr, 0);
990 /* two dummy got entries */
991 put32(ptr + 4, 0);
992 put32(ptr + 8, 0);
993 #else
994 /* keep space for _DYNAMIC pointer, if present */
995 put32(ptr, 0);
996 put32(ptr + 4, 0);
997 /* two dummy got entries */
998 put32(ptr + 8, 0);
999 put32(ptr + 12, 0);
1000 put32(ptr + 16, 0);
1001 put32(ptr + 20, 0);
1002 #endif
1003 }
1004
1005 /* put a got entry corresponding to a symbol in symtab_section. 'size'
1006 and 'info' can be modifed if more precise info comes from the DLL */
1007 static void put_got_entry(TCCState *s1,
1008 int reloc_type, unsigned long size, int info,
1009 int sym_index)
1010 {
1011 int index;
1012 const char *name;
1013 ElfW(Sym) *sym;
1014 unsigned long offset;
1015 int *ptr;
1016
1017 if (!s1->got)
1018 build_got(s1);
1019
1020 /* if a got entry already exists for that symbol, no need to add one */
1021 if (sym_index < s1->nb_sym_attrs &&
1022 s1->sym_attrs[sym_index].got_offset)
1023 return;
1024
1025 alloc_sym_attr(s1, sym_index)->got_offset = s1->got->data_offset;
1026
1027 if (s1->dynsym) {
1028 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1029 name = symtab_section->link->data + sym->st_name;
1030 offset = sym->st_value;
1031 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
1032 if (reloc_type ==
1033 #ifdef TCC_TARGET_X86_64
1034 R_X86_64_JUMP_SLOT
1035 #else
1036 R_386_JMP_SLOT
1037 #endif
1038 ) {
1039 Section *plt;
1040 uint8_t *p;
1041 int modrm;
1042
1043 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1044 modrm = 0x25;
1045 #else
1046 /* if we build a DLL, we add a %ebx offset */
1047 if (s1->output_type == TCC_OUTPUT_DLL)
1048 modrm = 0xa3;
1049 else
1050 modrm = 0x25;
1051 #endif
1052
1053 /* add a PLT entry */
1054 plt = s1->plt;
1055 if (plt->data_offset == 0) {
1056 /* first plt entry */
1057 p = section_ptr_add(plt, 16);
1058 p[0] = 0xff; /* pushl got + PTR_SIZE */
1059 p[1] = modrm + 0x10;
1060 put32(p + 2, PTR_SIZE);
1061 p[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */
1062 p[7] = modrm;
1063 put32(p + 8, PTR_SIZE * 2);
1064 }
1065
1066 p = section_ptr_add(plt, 16);
1067 p[0] = 0xff; /* jmp *(got + x) */
1068 p[1] = modrm;
1069 put32(p + 2, s1->got->data_offset);
1070 p[6] = 0x68; /* push $xxx */
1071 put32(p + 7, (plt->data_offset - 32) >> 1);
1072 p[11] = 0xe9; /* jmp plt_start */
1073 put32(p + 12, -(plt->data_offset));
1074
1075 /* the symbol is modified so that it will be relocated to
1076 the PLT */
1077 #if !defined(TCC_OUTPUT_DLL_WITH_PLT)
1078 if (s1->output_type == TCC_OUTPUT_EXE)
1079 #endif
1080 offset = plt->data_offset - 16;
1081 }
1082 #elif defined(TCC_TARGET_ARM)
1083 if (reloc_type == R_ARM_JUMP_SLOT) {
1084 Section *plt;
1085 uint8_t *p;
1086
1087 /* if we build a DLL, we add a %ebx offset */
1088 if (s1->output_type == TCC_OUTPUT_DLL)
1089 tcc_error("DLLs unimplemented!");
1090
1091 /* add a PLT entry */
1092 plt = s1->plt;
1093 if (plt->data_offset == 0) {
1094 /* first plt entry */
1095 p = section_ptr_add(plt, 16);
1096 put32(p, 0xe52de004); /* push {lr} */
1097 put32(p+4, 0xe59fe010); /* ldr lr, [pc, #16] */
1098 put32(p+8, 0xe08fe00e); /* add lr, pc, lr */
1099 put32(p+12, 0xe5bef008); /* ldr pc, [lr, #8]! */
1100 }
1101
1102 if (s1->sym_attrs[sym_index].plt_thumb_stub) {
1103 p = section_ptr_add(plt, 20);
1104 put32(p, 0x4778); /* bx pc */
1105 put32(p+2, 0x46c0); /* nop */
1106 p += 4;
1107 } else
1108 p = section_ptr_add(plt, 16);
1109 put32(p, 0xe59fc004); /* ldr ip, [pc, #4] ; GOT entry offset */
1110 put32(p+4, 0xe08fc00c); /* add ip, pc, ip ; addr of GOT entry */
1111 put32(p+8, 0xe59cf000); /* ldr pc, [ip] ; jump to GOT entry */
1112 put32(p+12, s1->got->data_offset); /* GOT entry off once patched */
1113
1114 /* the symbol is modified so that it will be relocated to
1115 the PLT */
1116 if (s1->output_type == TCC_OUTPUT_EXE)
1117 offset = plt->data_offset - 16;
1118 }
1119 #elif defined(TCC_TARGET_C67)
1120 tcc_error("C67 got not implemented");
1121 #else
1122 #error unsupported CPU
1123 #endif
1124 index = put_elf_sym(s1->dynsym, offset,
1125 size, info, 0, sym->st_shndx, name);
1126 /* put a got entry */
1127 put_elf_reloc(s1->dynsym, s1->got,
1128 s1->got->data_offset,
1129 reloc_type, index);
1130 }
1131 ptr = section_ptr_add(s1->got, PTR_SIZE);
1132 *ptr = 0;
1133 }
1134
1135 /* build GOT and PLT entries */
1136 ST_FUNC void build_got_entries(TCCState *s1)
1137 {
1138 Section *s;
1139 ElfW_Rel *rel;
1140 ElfW(Sym) *sym;
1141 int i, type, reloc_type, sym_index;
1142
1143 for(i = 1; i < s1->nb_sections; i++) {
1144 s = s1->sections[i];
1145 if (s->sh_type != SHT_RELX)
1146 continue;
1147 /* no need to handle got relocations */
1148 if (s->link != symtab_section)
1149 continue;
1150 for_each_elem(s, 0, rel, ElfW_Rel) {
1151 type = ELFW(R_TYPE)(rel->r_info);
1152 switch(type) {
1153 #if defined(TCC_TARGET_I386)
1154 case R_386_GOT32:
1155 case R_386_GOTOFF:
1156 case R_386_GOTPC:
1157 case R_386_PLT32:
1158 if (!s1->got)
1159 build_got(s1);
1160 if (type == R_386_GOT32 || type == R_386_PLT32) {
1161 sym_index = ELFW(R_SYM)(rel->r_info);
1162 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1163 /* look at the symbol got offset. If none, then add one */
1164 if (type == R_386_GOT32)
1165 reloc_type = R_386_GLOB_DAT;
1166 else
1167 reloc_type = R_386_JMP_SLOT;
1168 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1169 sym_index);
1170 }
1171 break;
1172 #elif defined(TCC_TARGET_ARM)
1173 case R_ARM_GOT32:
1174 case R_ARM_GOTOFF:
1175 case R_ARM_GOTPC:
1176 case R_ARM_PLT32:
1177 if (!s1->got)
1178 build_got(s1);
1179 if (type == R_ARM_GOT32 || type == R_ARM_PLT32) {
1180 sym_index = ELFW(R_SYM)(rel->r_info);
1181 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1182 /* look at the symbol got offset. If none, then add one */
1183 if (type == R_ARM_GOT32)
1184 reloc_type = R_ARM_GLOB_DAT;
1185 else
1186 reloc_type = R_ARM_JUMP_SLOT;
1187 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1188 sym_index);
1189 }
1190 break;
1191 case R_ARM_THM_JUMP24:
1192 sym_index = ELFW(R_SYM)(rel->r_info);
1193 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1194 /* We are relocating a jump from thumb code to arm code */
1195 if (sym->st_shndx != SHN_UNDEF && !(sym->st_value & 1)) {
1196 int index;
1197 uint8_t *p;
1198 char *name, buf[1024];
1199 Section *text_section;
1200
1201 name = symtab_section->link->data + sym->st_name;
1202 text_section = s1->sections[sym->st_shndx];
1203 /* Modify reloc to target a thumb stub to switch to ARM */
1204 snprintf(buf, sizeof(buf), "%s_from_thumb", name);
1205 index = put_elf_sym(symtab_section,
1206 text_section->data_offset + 1,
1207 sym->st_size, sym->st_info, 0,
1208 sym->st_shndx, buf);
1209 rel->r_info = ELFW(R_INFO)(index, type);
1210 /* Create a thumb stub fonction to switch to ARM mode */
1211 put_elf_reloc(symtab_section, text_section,
1212 text_section->data_offset, R_ARM_JUMP24,
1213 sym_index);
1214 p = section_ptr_add(text_section, 8);
1215 put32(p, 0x4778); /* bx pc */
1216 put32(p+2, 0x46c0); /* nop */
1217 put32(p+4, 0xeafffffe); /* b $sym */
1218 }
1219 #elif defined(TCC_TARGET_C67)
1220 case R_C60_GOT32:
1221 case R_C60_GOTOFF:
1222 case R_C60_GOTPC:
1223 case R_C60_PLT32:
1224 if (!s1->got)
1225 build_got(s1);
1226 if (type == R_C60_GOT32 || type == R_C60_PLT32) {
1227 sym_index = ELFW(R_SYM)(rel->r_info);
1228 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1229 /* look at the symbol got offset. If none, then add one */
1230 if (type == R_C60_GOT32)
1231 reloc_type = R_C60_GLOB_DAT;
1232 else
1233 reloc_type = R_C60_JMP_SLOT;
1234 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1235 sym_index);
1236 }
1237 break;
1238 #elif defined(TCC_TARGET_X86_64)
1239 case R_X86_64_GOT32:
1240 case R_X86_64_GOTTPOFF:
1241 case R_X86_64_GOTPCREL:
1242 case R_X86_64_PLT32:
1243 if (!s1->got)
1244 build_got(s1);
1245 if (type == R_X86_64_GOT32 || type == R_X86_64_GOTPCREL ||
1246 type == R_X86_64_PLT32) {
1247 sym_index = ELFW(R_SYM)(rel->r_info);
1248 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1249 /* look at the symbol got offset. If none, then add one */
1250 if (type == R_X86_64_GOT32 || type == R_X86_64_GOTPCREL)
1251 reloc_type = R_X86_64_GLOB_DAT;
1252 else
1253 reloc_type = R_X86_64_JUMP_SLOT;
1254 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1255 sym_index);
1256 }
1257 break;
1258 #else
1259 #error unsupported CPU
1260 #endif
1261 default:
1262 break;
1263 }
1264 }
1265 }
1266 }
1267
1268 ST_FUNC Section *new_symtab(TCCState *s1,
1269 const char *symtab_name, int sh_type, int sh_flags,
1270 const char *strtab_name,
1271 const char *hash_name, int hash_sh_flags)
1272 {
1273 Section *symtab, *strtab, *hash;
1274 int *ptr, nb_buckets;
1275
1276 symtab = new_section(s1, symtab_name, sh_type, sh_flags);
1277 symtab->sh_entsize = sizeof(ElfW(Sym));
1278 strtab = new_section(s1, strtab_name, SHT_STRTAB, sh_flags);
1279 put_elf_str(strtab, "");
1280 symtab->link = strtab;
1281 put_elf_sym(symtab, 0, 0, 0, 0, 0, NULL);
1282
1283 nb_buckets = 1;
1284
1285 hash = new_section(s1, hash_name, SHT_HASH, hash_sh_flags);
1286 hash->sh_entsize = sizeof(int);
1287 symtab->hash = hash;
1288 hash->link = symtab;
1289
1290 ptr = section_ptr_add(hash, (2 + nb_buckets + 1) * sizeof(int));
1291 ptr[0] = nb_buckets;
1292 ptr[1] = 1;
1293 memset(ptr + 2, 0, (nb_buckets + 1) * sizeof(int));
1294 return symtab;
1295 }
1296
1297 /* put dynamic tag */
1298 static void put_dt(Section *dynamic, int dt, addr_t val)
1299 {
1300 ElfW(Dyn) *dyn;
1301 dyn = section_ptr_add(dynamic, sizeof(ElfW(Dyn)));
1302 dyn->d_tag = dt;
1303 dyn->d_un.d_val = val;
1304 }
1305
1306 static void add_init_array_defines(TCCState *s1, const char *section_name)
1307 {
1308 Section *s;
1309 long end_offset;
1310 char sym_start[1024];
1311 char sym_end[1024];
1312
1313 snprintf(sym_start, sizeof(sym_start), "__%s_start", section_name + 1);
1314 snprintf(sym_end, sizeof(sym_end), "__%s_end", section_name + 1);
1315
1316 s = find_section(s1, section_name);
1317 if (!s) {
1318 end_offset = 0;
1319 s = data_section;
1320 } else {
1321 end_offset = s->data_offset;
1322 }
1323
1324 add_elf_sym(symtab_section,
1325 0, 0,
1326 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1327 s->sh_num, sym_start);
1328 add_elf_sym(symtab_section,
1329 end_offset, 0,
1330 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1331 s->sh_num, sym_end);
1332 }
1333
1334 ST_FUNC void tcc_add_bcheck(TCCState *s1)
1335 {
1336 #ifdef CONFIG_TCC_BCHECK
1337 unsigned long *ptr;
1338 Section *init_section;
1339 unsigned char *pinit;
1340 int sym_index;
1341
1342 if (0 == s1->do_bounds_check)
1343 return;
1344
1345 /* XXX: add an object file to do that */
1346 ptr = section_ptr_add(bounds_section, sizeof(unsigned long));
1347 *ptr = 0;
1348 add_elf_sym(symtab_section, 0, 0,
1349 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1350 bounds_section->sh_num, "__bounds_start");
1351 #ifdef TCC_TARGET_I386
1352 if (s1->output_type != TCC_OUTPUT_MEMORY) {
1353 /* add 'call __bound_init()' in .init section */
1354 init_section = find_section(s1, ".init");
1355 pinit = section_ptr_add(init_section, 5);
1356 pinit[0] = 0xe8;
1357 put32(pinit + 1, -4);
1358 sym_index = find_elf_sym(symtab_section, "__bound_init");
1359 put_elf_reloc(symtab_section, init_section,
1360 init_section->data_offset - 4, R_386_PC32, sym_index);
1361 }
1362 #endif
1363 #endif
1364 }
1365
1366 static inline int tcc_add_support(TCCState *s1, const char *filename)
1367 {
1368 char buf[1024];
1369 snprintf(buf, sizeof(buf), "%s/%s", s1->tcc_lib_path, filename);
1370 return tcc_add_file(s1, buf);
1371 }
1372
1373 /* add tcc runtime libraries */
1374 ST_FUNC void tcc_add_runtime(TCCState *s1)
1375 {
1376 tcc_add_bcheck(s1);
1377
1378 /* add libc */
1379 if (!s1->nostdlib) {
1380 tcc_add_library(s1, "c");
1381 #ifdef CONFIG_USE_LIBGCC
1382 if (!s1->static_link)
1383 tcc_add_file(s1, TCC_LIBGCC);
1384 else
1385 tcc_add_support(s1, "libtcc1.a");
1386 #else
1387 tcc_add_support(s1, "libtcc1.a");
1388 #endif
1389 /* add crt end if not memory output */
1390 if (s1->output_type != TCC_OUTPUT_MEMORY)
1391 tcc_add_crt(s1, "crtn.o");
1392 }
1393 }
1394
1395 /* add various standard linker symbols (must be done after the
1396 sections are filled (for example after allocating common
1397 symbols)) */
1398 ST_FUNC void tcc_add_linker_symbols(TCCState *s1)
1399 {
1400 char buf[1024];
1401 int i;
1402 Section *s;
1403
1404 add_elf_sym(symtab_section,
1405 text_section->data_offset, 0,
1406 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1407 text_section->sh_num, "_etext");
1408 add_elf_sym(symtab_section,
1409 data_section->data_offset, 0,
1410 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1411 data_section->sh_num, "_edata");
1412 add_elf_sym(symtab_section,
1413 bss_section->data_offset, 0,
1414 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1415 bss_section->sh_num, "_end");
1416 /* horrible new standard ldscript defines */
1417 add_init_array_defines(s1, ".preinit_array");
1418 add_init_array_defines(s1, ".init_array");
1419 add_init_array_defines(s1, ".fini_array");
1420
1421 /* add start and stop symbols for sections whose name can be
1422 expressed in C */
1423 for(i = 1; i < s1->nb_sections; i++) {
1424 s = s1->sections[i];
1425 if (s->sh_type == SHT_PROGBITS &&
1426 (s->sh_flags & SHF_ALLOC)) {
1427 const char *p;
1428 int ch;
1429
1430 /* check if section name can be expressed in C */
1431 p = s->name;
1432 for(;;) {
1433 ch = *p;
1434 if (!ch)
1435 break;
1436 if (!isid(ch) && !isnum(ch))
1437 goto next_sec;
1438 p++;
1439 }
1440 snprintf(buf, sizeof(buf), "__start_%s", s->name);
1441 add_elf_sym(symtab_section,
1442 0, 0,
1443 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1444 s->sh_num, buf);
1445 snprintf(buf, sizeof(buf), "__stop_%s", s->name);
1446 add_elf_sym(symtab_section,
1447 s->data_offset, 0,
1448 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1449 s->sh_num, buf);
1450 }
1451 next_sec: ;
1452 }
1453 }
1454
1455 static void tcc_output_binary(TCCState *s1, FILE *f,
1456 const int *sec_order)
1457 {
1458 Section *s;
1459 int i, offset, size;
1460
1461 offset = 0;
1462 for(i=1;i<s1->nb_sections;i++) {
1463 s = s1->sections[sec_order[i]];
1464 if (s->sh_type != SHT_NOBITS &&
1465 (s->sh_flags & SHF_ALLOC)) {
1466 while (offset < s->sh_offset) {
1467 fputc(0, f);
1468 offset++;
1469 }
1470 size = s->sh_size;
1471 fwrite(s->data, 1, size, f);
1472 offset += size;
1473 }
1474 }
1475 }
1476
1477 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1478 #define HAVE_PHDR 1
1479 #define EXTRA_RELITEMS 14
1480
1481 /* move the relocation value from .dynsym to .got */
1482 void patch_dynsym_undef(TCCState *s1, Section *s)
1483 {
1484 uint32_t *gotd = (void *)s1->got->data;
1485 ElfW(Sym) *sym;
1486
1487 gotd += 3; /* dummy entries in .got */
1488 /* relocate symbols in .dynsym */
1489 for_each_elem(s, 1, sym, ElfW(Sym)) {
1490 if (sym->st_shndx == SHN_UNDEF) {
1491 *gotd++ = sym->st_value + 6; /* XXX 6 is magic ? */
1492 sym->st_value = 0;
1493 }
1494 }
1495 }
1496 #else
1497 #define HAVE_PHDR 0
1498 #define EXTRA_RELITEMS 9
1499
1500 /* zero plt offsets of weak symbols in .dynsym */
1501 void patch_dynsym_undef(TCCState *s1, Section *s)
1502 {
1503 ElfW(Sym) *sym;
1504
1505 for_each_elem(s, 1, sym, ElfW(Sym))
1506 if (sym->st_shndx == SHN_UNDEF && ELFW(ST_BIND)(sym->st_info) == STB_WEAK)
1507 sym->st_value = 0;
1508 }
1509 #endif
1510
1511 ST_FUNC void fill_got_entry(TCCState *s1, ElfW_Rel *rel)
1512 {
1513 int sym_index = ELFW(R_SYM) (rel->r_info);
1514 ElfW(Sym) *sym = &((ElfW(Sym) *) symtab_section->data)[sym_index];
1515 unsigned long offset;
1516
1517 if (sym_index >= s1->nb_sym_attrs)
1518 return;
1519 offset = s1->sym_attrs[sym_index].got_offset;
1520 section_reserve(s1->got, offset + PTR_SIZE);
1521 #ifdef TCC_TARGET_X86_64
1522 /* only works for x86-64 */
1523 put32(s1->got->data + offset + 4, sym->st_value >> 32);
1524 #endif
1525 put32(s1->got->data + offset, sym->st_value & 0xffffffff);
1526 }
1527
1528 /* Perform relocation to GOT or PLT entries */
1529 ST_FUNC void fill_got(TCCState *s1)
1530 {
1531 Section *s;
1532 ElfW_Rel *rel;
1533 int i;
1534
1535 for(i = 1; i < s1->nb_sections; i++) {
1536 s = s1->sections[i];
1537 if (s->sh_type != SHT_RELX)
1538 continue;
1539 /* no need to handle got relocations */
1540 if (s->link != symtab_section)
1541 continue;
1542 for_each_elem(s, 0, rel, ElfW_Rel) {
1543 switch (ELFW(R_TYPE) (rel->r_info)) {
1544 #ifdef TCC_TARGET_X86_64
1545 case R_X86_64_GOT32:
1546 case R_X86_64_GOTPCREL:
1547 case R_X86_64_PLT32:
1548 fill_got_entry(s1, rel);
1549 break;
1550 #endif
1551 }
1552 }
1553 }
1554 }
1555
1556 /* Bind symbols of executable: resolve undefined symbols from exported symbols
1557 in shared libraries and export non local defined symbols to shared libraries
1558 if -rdynamic switch was given on command line */
1559 static void bind_exe_dynsyms(TCCState *s1)
1560 {
1561 const char *name;
1562 int sym_index, index;
1563 ElfW(Sym) *sym, *esym;
1564 int type;
1565
1566 /* Resolve undefined symbols from dynamic symbols. When there is a match:
1567 - if STT_FUNC or STT_GNU_IFUNC symbol -> add it in PLT
1568 - if STT_OBJECT symbol -> add it in .bss section with suitable reloc */
1569 for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
1570 if (sym->st_shndx == SHN_UNDEF) {
1571 name = symtab_section->link->data + sym->st_name;
1572 sym_index = find_elf_sym(s1->dynsymtab_section, name);
1573 if (sym_index) {
1574 esym = &((ElfW(Sym) *)s1->dynsymtab_section->data)[sym_index];
1575 type = ELFW(ST_TYPE)(esym->st_info);
1576 if ((type == STT_FUNC) || (type == STT_GNU_IFUNC)) {
1577 /* Indirect functions shall have STT_FUNC type in executable
1578 * dynsym section. Indeed, a dlsym call following a lazy
1579 * resolution would pick the symbol value from the
1580 * executable dynsym entry which would contain the address
1581 * of the function wanted by the caller of dlsym instead of
1582 * the address of the function that would return that
1583 * address */
1584 put_got_entry(s1, R_JMP_SLOT, esym->st_size,
1585 ELFW(ST_INFO)(STB_GLOBAL,STT_FUNC),
1586 sym - (ElfW(Sym) *)symtab_section->data);
1587 } else if (type == STT_OBJECT) {
1588 unsigned long offset;
1589 ElfW(Sym) *dynsym;
1590 offset = bss_section->data_offset;
1591 /* XXX: which alignment ? */
1592 offset = (offset + 16 - 1) & -16;
1593 index = put_elf_sym(s1->dynsym, offset, esym->st_size,
1594 esym->st_info, 0, bss_section->sh_num,
1595 name);
1596 /* Ensure R_COPY works for weak symbol aliases */
1597 if (ELFW(ST_BIND)(esym->st_info) == STB_WEAK) {
1598 for_each_elem(s1->dynsymtab_section, 1, dynsym, ElfW(Sym)) {
1599 if ((dynsym->st_value == esym->st_value)
1600 && (ELFW(ST_BIND)(dynsym->st_info) == STB_GLOBAL)) {
1601 char *dynname = s1->dynsymtab_section->link->data
1602 + dynsym->st_name;
1603 put_elf_sym(s1->dynsym, offset, dynsym->st_size,
1604 dynsym->st_info, 0,
1605 bss_section->sh_num, dynname);
1606 break;
1607 }
1608 }
1609 }
1610 put_elf_reloc(s1->dynsym, bss_section,
1611 offset, R_COPY, index);
1612 offset += esym->st_size;
1613 bss_section->data_offset = offset;
1614 }
1615 } else {
1616 /* STB_WEAK undefined symbols are accepted */
1617 /* XXX: _fp_hw seems to be part of the ABI, so we ignore it */
1618 if (ELFW(ST_BIND)(sym->st_info) == STB_WEAK ||
1619 !strcmp(name, "_fp_hw")) {
1620 } else {
1621 tcc_error_noabort("undefined symbol '%s'", name);
1622 }
1623 }
1624 } else if (s1->rdynamic && ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
1625 /* if -rdynamic option, then export all non local symbols */
1626 name = symtab_section->link->data + sym->st_name;
1627 put_elf_sym(s1->dynsym, sym->st_value, sym->st_size, sym->st_info,
1628 0, sym->st_shndx, name);
1629 }
1630 }
1631 }
1632
1633 /* Bind symbols of libraries: export non local symbols of executable that
1634 resolve undefined symbols of shared libraries */
1635 static void bind_libs_dynsyms(TCCState *s1)
1636 {
1637 const char *name;
1638 int sym_index;
1639 ElfW(Sym) *sym, *esym;
1640
1641 /* now look at unresolved dynamic symbols and export
1642 corresponding symbol */
1643 for_each_elem(s1->dynsymtab_section, 1, esym, ElfW(Sym)) {
1644 if (esym->st_shndx == SHN_UNDEF) {
1645 name = s1->dynsymtab_section->link->data + esym->st_name;
1646 sym_index = find_elf_sym(symtab_section, name);
1647 if (sym_index) {
1648 /* XXX: avoid adding a symbol if already present because of
1649 -rdynamic ? */
1650 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1651 put_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
1652 sym->st_info, 0, sym->st_shndx, name);
1653 } else {
1654 /* weak symbols can stay undefined */
1655 if (ELFW(ST_BIND)(esym->st_info) != STB_WEAK)
1656 tcc_warning("undefined dynamic symbol '%s'", name);
1657 }
1658 }
1659 }
1660 }
1661
1662 /* Export all non local symbols (for shared libraries) */
1663 static void export_global_syms(TCCState *s1)
1664 {
1665 int nb_syms, dynindex, index;
1666 const char *name;
1667 ElfW(Sym) *sym;
1668
1669 nb_syms = symtab_section->data_offset / sizeof(ElfW(Sym));
1670 s1->symtab_to_dynsym = tcc_mallocz(sizeof(int) * nb_syms);
1671 for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
1672 if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
1673 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1674 int type = ELFW(ST_TYPE)(sym->st_info);
1675 if ((type == STT_FUNC || type == STT_GNU_IFUNC)
1676 && sym->st_shndx == SHN_UNDEF) {
1677 int visibility = ELFW(ST_BIND)(sym->st_info);
1678 put_got_entry(s1, R_JMP_SLOT, sym->st_size,
1679 ELFW(ST_INFO)(visibility, STT_FUNC),
1680 sym - (ElfW(Sym) *) symtab_section->data);
1681 } else if (type == STT_OBJECT) {
1682 put_got_entry(s1, R_X86_64_GLOB_DAT, sym->st_size, sym->st_info,
1683 sym - (ElfW(Sym) *) symtab_section->data);
1684 } else
1685 #endif
1686 {
1687 name = symtab_section->link->data + sym->st_name;
1688 dynindex = put_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
1689 sym->st_info, 0, sym->st_shndx, name);
1690 index = sym - (ElfW(Sym) *) symtab_section->data;
1691 s1->symtab_to_dynsym[index] = dynindex;
1692 }
1693 }
1694 }
1695 }
1696
1697 /* relocate the PLT: compute addresses and offsets in the PLT now that final
1698 address for PLT and GOT are known (see fill_program_header) */
1699 static void relocate_plt(TCCState *s1)
1700 {
1701 uint8_t *p, *p_end;
1702
1703 p = s1->plt->data;
1704 p_end = p + s1->plt->data_offset;
1705 if (p < p_end) {
1706 #if defined(TCC_TARGET_I386)
1707 put32(p + 2, get32(p + 2) + s1->got->sh_addr);
1708 put32(p + 8, get32(p + 8) + s1->got->sh_addr);
1709 p += 16;
1710 while (p < p_end) {
1711 put32(p + 2, get32(p + 2) + s1->got->sh_addr);
1712 p += 16;
1713 }
1714 #elif defined(TCC_TARGET_X86_64)
1715 int x = s1->got->sh_addr - s1->plt->sh_addr - 6;
1716 put32(p + 2, get32(p + 2) + x);
1717 put32(p + 8, get32(p + 8) + x - 6);
1718 p += 16;
1719 while (p < p_end) {
1720 put32(p + 2, get32(p + 2) + x + s1->plt->data - p);
1721 p += 16;
1722 }
1723 #elif defined(TCC_TARGET_ARM)
1724 int x;
1725 x=s1->got->sh_addr - s1->plt->sh_addr - 12;
1726 p += 16;
1727 while (p < p_end) {
1728 if (get32(p) == 0x46c04778) /* PLT Thumb stub present */
1729 p += 4;
1730 put32(p + 12, x + get32(p + 12) + s1->plt->data - p);
1731 p += 16;
1732 }
1733 #elif defined(TCC_TARGET_C67)
1734 /* XXX: TODO */
1735 #else
1736 #error unsupported CPU
1737 #endif
1738 }
1739 }
1740
1741 /* Allocate strings for section names and decide if an unallocated section
1742 should be output.
1743
1744 NOTE: the strsec section comes last, so its size is also correct ! */
1745 static void alloc_sec_names(TCCState *s1, int file_type, Section *strsec)
1746 {
1747 int i;
1748 Section *s;
1749
1750 /* Allocate strings for section names */
1751 for(i = 1; i < s1->nb_sections; i++) {
1752 s = s1->sections[i];
1753 s->sh_name = put_elf_str(strsec, s->name);
1754 /* when generating a DLL, we include relocations but we may
1755 patch them */
1756 if (file_type == TCC_OUTPUT_DLL &&
1757 s->sh_type == SHT_RELX &&
1758 !(s->sh_flags & SHF_ALLOC)) {
1759 /* gr: avoid bogus relocs for empty (debug) sections */
1760 if (s1->sections[s->sh_info]->sh_flags & SHF_ALLOC)
1761 prepare_dynamic_rel(s1, s);
1762 else if (s1->do_debug)
1763 s->sh_size = s->data_offset;
1764 } else if (s1->do_debug ||
1765 file_type == TCC_OUTPUT_OBJ ||
1766 (s->sh_flags & SHF_ALLOC) ||
1767 i == (s1->nb_sections - 1)) {
1768 /* we output all sections if debug or object file */
1769 s->sh_size = s->data_offset;
1770 }
1771 }
1772 }
1773
1774 /* Info to be copied in dynamic section */
1775 struct dyn_inf {
1776 Section *dynamic;
1777 Section *dynstr;
1778 unsigned long dyn_rel_off;
1779 addr_t rel_addr;
1780 addr_t rel_size;
1781 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1782 addr_t bss_addr;
1783 addr_t bss_size;
1784 #endif
1785 };
1786
1787 /* Assign sections to segments and decide how are sections laid out when loaded
1788 in memory. This function also fills corresponding program headers. */
1789 static int layout_sections(TCCState *s1, ElfW(Phdr) *phdr, int phnum,
1790 Section *interp, struct dyn_inf *dyninf,
1791 int *sec_order)
1792 {
1793 int i, j, k, file_type, sh_order_index, file_offset;
1794 long long tmp;
1795 addr_t addr;
1796 ElfW(Phdr) *ph;
1797 Section *s;
1798
1799 file_type = s1->output_type;
1800 sh_order_index = 1;
1801 if (s1->output_format == TCC_OUTPUT_FORMAT_ELF)
1802 file_offset = sizeof(ElfW(Ehdr)) + phnum * sizeof(ElfW(Phdr));
1803 else
1804 file_offset = 0;
1805
1806 if (phnum > 0) {
1807 if (s1->has_text_addr) {
1808 int a_offset, p_offset;
1809 addr = s1->text_addr;
1810 /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
1811 ELF_PAGE_SIZE */
1812 a_offset = (int) (addr & (s1->section_align - 1));
1813 p_offset = file_offset & (s1->section_align - 1);
1814 if (a_offset < p_offset)
1815 a_offset += s1->section_align;
1816 file_offset += (a_offset - p_offset);
1817 } else {
1818 if (file_type == TCC_OUTPUT_DLL)
1819 addr = 0;
1820 else
1821 addr = ELF_START_ADDR;
1822 /* compute address after headers */
1823 addr += (file_offset & (s1->section_align - 1));
1824 }
1825
1826 ph = &phdr[0];
1827 /* Leave one program headers for the program interpreter and one for
1828 the program header table itself if needed. These are done later as
1829 they require section layout to be done first. */
1830 if (interp)
1831 ph += 1 + HAVE_PHDR;
1832
1833 /* dynamic relocation table information, for .dynamic section */
1834 dyninf->rel_addr = dyninf->rel_size = 0;
1835 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1836 dyninf->bss_addr = dyninf->bss_size = 0;
1837 #endif
1838
1839 for(j = 0; j < 2; j++) {
1840 ph->p_type = PT_LOAD;
1841 if (j == 0)
1842 ph->p_flags = PF_R | PF_X;
1843 else
1844 ph->p_flags = PF_R | PF_W;
1845 ph->p_align = s1->section_align;
1846
1847 /* Decide the layout of sections loaded in memory. This must
1848 be done before program headers are filled since they contain
1849 info about the layout. We do the following ordering: interp,
1850 symbol tables, relocations, progbits, nobits */
1851 /* XXX: do faster and simpler sorting */
1852 for(k = 0; k < 5; k++) {
1853 for(i = 1; i < s1->nb_sections; i++) {
1854 s = s1->sections[i];
1855 /* compute if section should be included */
1856 if (j == 0) {
1857 if ((s->sh_flags & (SHF_ALLOC | SHF_WRITE)) !=
1858 SHF_ALLOC)
1859 continue;
1860 } else {
1861 if ((s->sh_flags & (SHF_ALLOC | SHF_WRITE)) !=
1862 (SHF_ALLOC | SHF_WRITE))
1863 continue;
1864 }
1865 if (s == interp) {
1866 if (k != 0)
1867 continue;
1868 } else if (s->sh_type == SHT_DYNSYM ||
1869 s->sh_type == SHT_STRTAB ||
1870 s->sh_type == SHT_HASH) {
1871 if (k != 1)
1872 continue;
1873 } else if (s->sh_type == SHT_RELX) {
1874 if (k != 2)
1875 continue;
1876 } else if (s->sh_type == SHT_NOBITS) {
1877 if (k != 4)
1878 continue;
1879 } else {
1880 if (k != 3)
1881 continue;
1882 }
1883 sec_order[sh_order_index++] = i;
1884
1885 /* section matches: we align it and add its size */
1886 tmp = addr;
1887 addr = (addr + s->sh_addralign - 1) &
1888 ~(s->sh_addralign - 1);
1889 file_offset += (int) ( addr - tmp );
1890 s->sh_offset = file_offset;
1891 s->sh_addr = addr;
1892
1893 /* update program header infos */
1894 if (ph->p_offset == 0) {
1895 ph->p_offset = file_offset;
1896 ph->p_vaddr = addr;
1897 ph->p_paddr = ph->p_vaddr;
1898 }
1899 /* update dynamic relocation infos */
1900 if (s->sh_type == SHT_RELX) {
1901 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1902 if (!strcmp(strsec->data + s->sh_name, ".rel.got")) {
1903 dyninf->rel_addr = addr;
1904 dyninf->rel_size += s->sh_size; /* XXX only first rel. */
1905 }
1906 if (!strcmp(strsec->data + s->sh_name, ".rel.bss")) {
1907 dyninf->bss_addr = addr;
1908 dyninf->bss_size = s->sh_size; /* XXX only first rel. */
1909 }
1910 #else
1911 if (dyninf->rel_size == 0)
1912 dyninf->rel_addr = addr;
1913 dyninf->rel_size += s->sh_size;
1914 #endif
1915 }
1916 addr += s->sh_size;
1917 if (s->sh_type != SHT_NOBITS)
1918 file_offset += s->sh_size;
1919 }
1920 }
1921 ph->p_filesz = file_offset - ph->p_offset;
1922 ph->p_memsz = addr - ph->p_vaddr;
1923 ph++;
1924 if (j == 0) {
1925 if (s1->output_format == TCC_OUTPUT_FORMAT_ELF) {
1926 /* if in the middle of a page, we duplicate the page in
1927 memory so that one copy is RX and the other is RW */
1928 if ((addr & (s1->section_align - 1)) != 0)
1929 addr += s1->section_align;
1930 } else {
1931 addr = (addr + s1->section_align - 1) & ~(s1->section_align - 1);
1932 file_offset = (file_offset + s1->section_align - 1) &
1933 ~(s1->section_align - 1);
1934 }
1935 }
1936 }
1937 }
1938
1939 /* all other sections come after */
1940 for(i = 1; i < s1->nb_sections; i++) {
1941 s = s1->sections[i];
1942 if (phnum > 0 && (s->sh_flags & SHF_ALLOC))
1943 continue;
1944 sec_order[sh_order_index++] = i;
1945
1946 file_offset = (file_offset + s->sh_addralign - 1) &
1947 ~(s->sh_addralign - 1);
1948 s->sh_offset = file_offset;
1949 if (s->sh_type != SHT_NOBITS)
1950 file_offset += s->sh_size;
1951 }
1952
1953 return file_offset;
1954 }
1955
1956 static void fill_unloadable_phdr(ElfW(Phdr) *phdr, int phnum, Section *interp,
1957 Section *dynamic)
1958 {
1959 ElfW(Phdr) *ph;
1960
1961 /* if interpreter, then add corresponding program header */
1962 if (interp) {
1963 ph = &phdr[0];
1964
1965 if (HAVE_PHDR)
1966 {
1967 int len = phnum * sizeof(ElfW(Phdr));
1968
1969 ph->p_type = PT_PHDR;
1970 ph->p_offset = sizeof(ElfW(Ehdr));
1971 ph->p_vaddr = interp->sh_addr - len;
1972 ph->p_paddr = ph->p_vaddr;
1973 ph->p_filesz = ph->p_memsz = len;
1974 ph->p_flags = PF_R | PF_X;
1975 ph->p_align = 4; /* interp->sh_addralign; */
1976 ph++;
1977 }
1978
1979 ph->p_type = PT_INTERP;
1980 ph->p_offset = interp->sh_offset;
1981 ph->p_vaddr = interp->sh_addr;
1982 ph->p_paddr = ph->p_vaddr;
1983 ph->p_filesz = interp->sh_size;
1984 ph->p_memsz = interp->sh_size;
1985 ph->p_flags = PF_R;
1986 ph->p_align = interp->sh_addralign;
1987 }
1988
1989 /* if dynamic section, then add corresponding program header */
1990 if (dynamic) {
1991 ph = &phdr[phnum - 1];
1992
1993 ph->p_type = PT_DYNAMIC;
1994 ph->p_offset = dynamic->sh_offset;
1995 ph->p_vaddr = dynamic->sh_addr;
1996 ph->p_paddr = ph->p_vaddr;
1997 ph->p_filesz = dynamic->sh_size;
1998 ph->p_memsz = dynamic->sh_size;
1999 ph->p_flags = PF_R | PF_W;
2000 ph->p_align = dynamic->sh_addralign;
2001 }
2002 }
2003
2004 /* Fill the dynamic section with tags describing the address and size of
2005 sections */
2006 static void fill_dynamic(TCCState *s1, struct dyn_inf *dyninf)
2007 {
2008 Section *dynamic;
2009
2010 dynamic = dyninf->dynamic;
2011
2012 /* put dynamic section entries */
2013 dynamic->data_offset = dyninf->dyn_rel_off;
2014 put_dt(dynamic, DT_HASH, s1->dynsym->hash->sh_addr);
2015 put_dt(dynamic, DT_STRTAB, dyninf->dynstr->sh_addr);
2016 put_dt(dynamic, DT_SYMTAB, s1->dynsym->sh_addr);
2017 put_dt(dynamic, DT_STRSZ, dyninf->dynstr->data_offset);
2018 put_dt(dynamic, DT_SYMENT, sizeof(ElfW(Sym)));
2019 #ifdef TCC_TARGET_X86_64
2020 put_dt(dynamic, DT_RELA, dyninf->rel_addr);
2021 put_dt(dynamic, DT_RELASZ, dyninf->rel_size);
2022 put_dt(dynamic, DT_RELAENT, sizeof(ElfW_Rel));
2023 #else
2024 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2025 put_dt(dynamic, DT_PLTGOT, s1->got->sh_addr);
2026 put_dt(dynamic, DT_PLTRELSZ, dyninf->rel_size);
2027 put_dt(dynamic, DT_JMPREL, dyninf->rel_addr);
2028 put_dt(dynamic, DT_PLTREL, DT_REL);
2029 put_dt(dynamic, DT_REL, dyninf->bss_addr);
2030 put_dt(dynamic, DT_RELSZ, dyninf->bss_size);
2031 #else
2032 put_dt(dynamic, DT_REL, dyninf->rel_addr);
2033 put_dt(dynamic, DT_RELSZ, dyninf->rel_size);
2034 put_dt(dynamic, DT_RELENT, sizeof(ElfW_Rel));
2035 #endif
2036 #endif
2037 if (s1->do_debug)
2038 put_dt(dynamic, DT_DEBUG, 0);
2039 put_dt(dynamic, DT_NULL, 0);
2040 }
2041
2042 /* Relocate remaining sections and symbols (that is those not related to
2043 dynamic linking) */
2044 static int final_sections_reloc(TCCState *s1)
2045 {
2046 int i;
2047 Section *s;
2048
2049 relocate_syms(s1, 0);
2050
2051 if (s1->nb_errors != 0)
2052 return -1;
2053
2054 /* relocate sections */
2055 /* XXX: ignore sections with allocated relocations ? */
2056 for(i = 1; i < s1->nb_sections; i++) {
2057 s = s1->sections[i];
2058 if (s->reloc && s != s1->got)
2059 relocate_section(s1, s);
2060 }
2061
2062 /* relocate relocation entries if the relocation tables are
2063 allocated in the executable */
2064 for(i = 1; i < s1->nb_sections; i++) {
2065 s = s1->sections[i];
2066 if ((s->sh_flags & SHF_ALLOC) &&
2067 s->sh_type == SHT_RELX) {
2068 relocate_rel(s1, s);
2069 }
2070 }
2071 return 0;
2072 }
2073
2074 /* Create an ELF file on disk.
2075 This function handle ELF specific layout requirements */
2076 static void tcc_output_elf(TCCState *s1, FILE *f, int phnum, ElfW(Phdr) *phdr,
2077 int file_offset, int *sec_order)
2078 {
2079 int i, shnum, offset, size, file_type;
2080 Section *s;
2081 ElfW(Ehdr) ehdr;
2082 ElfW(Shdr) shdr, *sh;
2083
2084 file_type = s1->output_type;
2085 shnum = s1->nb_sections;
2086
2087 memset(&ehdr, 0, sizeof(ehdr));
2088
2089 if (phnum > 0) {
2090 ehdr.e_phentsize = sizeof(ElfW(Phdr));
2091 ehdr.e_phnum = phnum;
2092 ehdr.e_phoff = sizeof(ElfW(Ehdr));
2093 }
2094
2095 /* align to 4 */
2096 file_offset = (file_offset + 3) & -4;
2097
2098 /* fill header */
2099 ehdr.e_ident[0] = ELFMAG0;
2100 ehdr.e_ident[1] = ELFMAG1;
2101 ehdr.e_ident[2] = ELFMAG2;
2102 ehdr.e_ident[3] = ELFMAG3;
2103 ehdr.e_ident[4] = ELFCLASSW;
2104 ehdr.e_ident[5] = ELFDATA2LSB;
2105 ehdr.e_ident[6] = EV_CURRENT;
2106 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2107 ehdr.e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
2108 #endif
2109 #ifdef TCC_TARGET_ARM
2110 #ifdef TCC_ARM_EABI
2111 ehdr.e_ident[EI_OSABI] = 0;
2112 ehdr.e_flags = EF_ARM_EABI_VER4;
2113 if (file_type == TCC_OUTPUT_EXE || file_type == TCC_OUTPUT_DLL)
2114 ehdr.e_flags |= EF_ARM_HASENTRY;
2115 if (s1->float_abi == ARM_HARD_FLOAT)
2116 ehdr.e_flags |= EF_ARM_VFP_FLOAT;
2117 else
2118 ehdr.e_flags |= EF_ARM_SOFT_FLOAT;
2119 #else
2120 ehdr.e_ident[EI_OSABI] = ELFOSABI_ARM;
2121 #endif
2122 #endif
2123 switch(file_type) {
2124 default:
2125 case TCC_OUTPUT_EXE:
2126 ehdr.e_type = ET_EXEC;
2127 ehdr.e_entry = get_elf_sym_addr(s1, "_start", 1);
2128 break;
2129 case TCC_OUTPUT_DLL:
2130 ehdr.e_type = ET_DYN;
2131 ehdr.e_entry = text_section->sh_addr; /* XXX: is it correct ? */
2132 break;
2133 case TCC_OUTPUT_OBJ:
2134 ehdr.e_type = ET_REL;
2135 break;
2136 }
2137 ehdr.e_machine = EM_TCC_TARGET;
2138 ehdr.e_version = EV_CURRENT;
2139 ehdr.e_shoff = file_offset;
2140 ehdr.e_ehsize = sizeof(ElfW(Ehdr));
2141 ehdr.e_shentsize = sizeof(ElfW(Shdr));
2142 ehdr.e_shnum = shnum;
2143 ehdr.e_shstrndx = shnum - 1;
2144
2145 fwrite(&ehdr, 1, sizeof(ElfW(Ehdr)), f);
2146 fwrite(phdr, 1, phnum * sizeof(ElfW(Phdr)), f);
2147 offset = sizeof(ElfW(Ehdr)) + phnum * sizeof(ElfW(Phdr));
2148
2149 sort_syms(s1, symtab_section);
2150 for(i = 1; i < s1->nb_sections; i++) {
2151 s = s1->sections[sec_order[i]];
2152 if (s->sh_type != SHT_NOBITS) {
2153 if (s->sh_type == SHT_DYNSYM)
2154 patch_dynsym_undef(s1, s);
2155 while (offset < s->sh_offset) {
2156 fputc(0, f);
2157 offset++;
2158 }
2159 size = s->sh_size;
2160 fwrite(s->data, 1, size, f);
2161 offset += size;
2162 }
2163 }
2164
2165 /* output section headers */
2166 while (offset < ehdr.e_shoff) {
2167 fputc(0, f);
2168 offset++;
2169 }
2170
2171 for(i = 0; i < s1->nb_sections; i++) {
2172 sh = &shdr;
2173 memset(sh, 0, sizeof(ElfW(Shdr)));
2174 s = s1->sections[i];
2175 if (s) {
2176 sh->sh_name = s->sh_name;
2177 sh->sh_type = s->sh_type;
2178 sh->sh_flags = s->sh_flags;
2179 sh->sh_entsize = s->sh_entsize;
2180 sh->sh_info = s->sh_info;
2181 if (s->link)
2182 sh->sh_link = s->link->sh_num;
2183 sh->sh_addralign = s->sh_addralign;
2184 sh->sh_addr = s->sh_addr;
2185 sh->sh_offset = s->sh_offset;
2186 sh->sh_size = s->sh_size;
2187 }
2188 fwrite(sh, 1, sizeof(ElfW(Shdr)), f);
2189 }
2190 }
2191
2192 /* Write an elf, coff or "binary" file */
2193 static int tcc_write_elf_file(TCCState *s1, const char *filename, int phnum,
2194 ElfW(Phdr) *phdr, int file_offset, int *sec_order)
2195 {
2196 int fd, mode, file_type;
2197 FILE *f;
2198
2199 file_type = s1->output_type;
2200 if (file_type == TCC_OUTPUT_OBJ)
2201 mode = 0666;
2202 else
2203 mode = 0777;
2204 unlink(filename);
2205 fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, mode);
2206 if (fd < 0) {
2207 tcc_error_noabort("could not write '%s'", filename);
2208 return -1;
2209 }
2210 f = fdopen(fd, "wb");
2211 if (s1->verbose)
2212 printf("<- %s\n", filename);
2213
2214 #ifdef TCC_TARGET_COFF
2215 if (s1->output_format == TCC_OUTPUT_FORMAT_COFF)
2216 tcc_output_coff(s1, f);
2217 else
2218 #endif
2219 if (s1->output_format == TCC_OUTPUT_FORMAT_ELF)
2220 tcc_output_elf(s1, f, phnum, phdr, file_offset, sec_order);
2221 else
2222 tcc_output_binary(s1, f, sec_order);
2223 fclose(f);
2224
2225 return 0;
2226 }
2227
2228 /* Output an elf, coff or binary file */
2229 /* XXX: suppress unneeded sections */
2230 static int elf_output_file(TCCState *s1, const char *filename)
2231 {
2232 int i, ret, phnum, shnum, file_type, file_offset, *sec_order;
2233 struct dyn_inf dyninf;
2234 ElfW(Phdr) *phdr;
2235 ElfW(Sym) *sym;
2236 Section *strsec, *interp, *dynamic, *dynstr;
2237
2238 file_type = s1->output_type;
2239 s1->nb_errors = 0;
2240
2241 /* if linking, also link in runtime libraries (libc, libgcc, etc.) */
2242 if (file_type != TCC_OUTPUT_OBJ) {
2243 tcc_add_runtime(s1);
2244 }
2245
2246 phdr = NULL;
2247 sec_order = NULL;
2248 interp = dynamic = dynstr = NULL; /* avoid warning */
2249 dyninf.dyn_rel_off = 0; /* avoid warning */
2250
2251 if (file_type != TCC_OUTPUT_OBJ) {
2252 relocate_common_syms();
2253
2254 tcc_add_linker_symbols(s1);
2255
2256 if (!s1->static_link) {
2257 if (file_type == TCC_OUTPUT_EXE) {
2258 char *ptr;
2259 /* allow override the dynamic loader */
2260 const char *elfint = getenv("LD_SO");
2261 if (elfint == NULL)
2262 elfint = DEFAULT_ELFINTERP(s1);
2263 /* add interpreter section only if executable */
2264 interp = new_section(s1, ".interp", SHT_PROGBITS, SHF_ALLOC);
2265 interp->sh_addralign = 1;
2266 ptr = section_ptr_add(interp, 1 + strlen(elfint));
2267 strcpy(ptr, elfint);
2268 }
2269
2270 /* add dynamic symbol table */
2271 s1->dynsym = new_symtab(s1, ".dynsym", SHT_DYNSYM, SHF_ALLOC,
2272 ".dynstr",
2273 ".hash", SHF_ALLOC);
2274 dynstr = s1->dynsym->link;
2275
2276 /* add dynamic section */
2277 dynamic = new_section(s1, ".dynamic", SHT_DYNAMIC,
2278 SHF_ALLOC | SHF_WRITE);
2279 dynamic->link = dynstr;
2280 dynamic->sh_entsize = sizeof(ElfW(Dyn));
2281
2282 /* add PLT */
2283 s1->plt = new_section(s1, ".plt", SHT_PROGBITS,
2284 SHF_ALLOC | SHF_EXECINSTR);
2285 s1->plt->sh_entsize = 4;
2286
2287 build_got(s1);
2288
2289 if (file_type == TCC_OUTPUT_EXE) {
2290 bind_exe_dynsyms(s1);
2291
2292 if (s1->nb_errors) {
2293 ret = -1;
2294 goto the_end;
2295 }
2296
2297 bind_libs_dynsyms(s1);
2298 } else /* shared library case: simply export all global symbols */
2299 export_global_syms(s1);
2300
2301 build_got_entries(s1);
2302
2303 /* add a list of needed dlls */
2304 for(i = 0; i < s1->nb_loaded_dlls; i++) {
2305 DLLReference *dllref = s1->loaded_dlls[i];
2306 if (dllref->level == 0)
2307 put_dt(dynamic, DT_NEEDED, put_elf_str(dynstr, dllref->name));
2308 }
2309
2310 if (s1->rpath)
2311 put_dt(dynamic, DT_RPATH, put_elf_str(dynstr, s1->rpath));
2312
2313 /* XXX: currently, since we do not handle PIC code, we
2314 must relocate the readonly segments */
2315 if (file_type == TCC_OUTPUT_DLL) {
2316 if (s1->soname)
2317 put_dt(dynamic, DT_SONAME, put_elf_str(dynstr, s1->soname));
2318 put_dt(dynamic, DT_TEXTREL, 0);
2319 }
2320
2321 if (s1->symbolic)
2322 put_dt(dynamic, DT_SYMBOLIC, 0);
2323
2324 /* add necessary space for other entries */
2325 dyninf.dyn_rel_off = dynamic->data_offset;
2326 dynamic->data_offset += sizeof(ElfW(Dyn)) * EXTRA_RELITEMS;
2327 } else {
2328 /* still need to build got entries in case of static link */
2329 build_got_entries(s1);
2330 }
2331 }
2332
2333 /* we add a section for symbols */
2334 strsec = new_section(s1, ".shstrtab", SHT_STRTAB, 0);
2335 put_elf_str(strsec, "");
2336
2337 /* compute number of sections */
2338 shnum = s1->nb_sections;
2339
2340 /* this array is used to reorder sections in the output file */
2341 sec_order = tcc_malloc(sizeof(int) * shnum);
2342 sec_order[0] = 0;
2343
2344 /* compute number of program headers */
2345 switch(file_type) {
2346 default:
2347 case TCC_OUTPUT_OBJ:
2348 phnum = 0;
2349 break;
2350 case TCC_OUTPUT_EXE:
2351 if (!s1->static_link)
2352 phnum = 4 + HAVE_PHDR;
2353 else
2354 phnum = 2;
2355 break;
2356 case TCC_OUTPUT_DLL:
2357 phnum = 3;
2358 break;
2359 }
2360
2361 /* Allocate strings for section names */
2362 alloc_sec_names(s1, file_type, strsec);
2363
2364 /* allocate program segment headers */
2365 phdr = tcc_mallocz(phnum * sizeof(ElfW(Phdr)));
2366
2367 /* compute section to program header mapping */
2368 file_offset = layout_sections(s1, phdr, phnum, interp, &dyninf, sec_order);
2369
2370 /* Fill remaining program header and finalize relocation related to dynamic
2371 linking. */
2372 if (phnum > 0) {
2373 fill_unloadable_phdr(phdr, phnum, interp, dynamic);
2374 if (dynamic) {
2375 dyninf.dynamic = dynamic;
2376 dyninf.dynstr = dynstr;
2377
2378 fill_dynamic(s1, &dyninf);
2379
2380 /* put in GOT the dynamic section address and relocate PLT */
2381 put32(s1->got->data, dynamic->sh_addr);
2382 if (file_type == TCC_OUTPUT_EXE
2383 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
2384 || file_type == TCC_OUTPUT_DLL
2385 #endif
2386 )
2387 relocate_plt(s1);
2388
2389 /* relocate symbols in .dynsym now that final addresses are known */
2390 for_each_elem(s1->dynsym, 1, sym, ElfW(Sym)) {
2391 /* relocate to PLT if symbol corresponds to a PLT entry */
2392 if (sym->st_shndx == SHN_UNDEF) {
2393 if (sym->st_value)
2394 sym->st_value += s1->plt->sh_addr;
2395 } else if (sym->st_shndx < SHN_LORESERVE) {
2396 /* do symbol relocation */
2397 sym->st_value += s1->sections[sym->st_shndx]->sh_addr;
2398 }
2399 }
2400 }
2401 }
2402
2403 /* if building executable or DLL, then relocate each section
2404 except the GOT which is already relocated */
2405 if (file_type != TCC_OUTPUT_OBJ) {
2406 ret = final_sections_reloc(s1);
2407 if (ret)
2408 goto the_end;
2409 }
2410
2411 /* Perform relocation to GOT or PLT entries */
2412 if (file_type == TCC_OUTPUT_EXE && s1->static_link)
2413 fill_got(s1);
2414
2415 /* Create the ELF file with name 'filename' */
2416 ret = tcc_write_elf_file(s1, filename, phnum, phdr, file_offset, sec_order);
2417 the_end:
2418 tcc_free(s1->symtab_to_dynsym);
2419 tcc_free(sec_order);
2420 tcc_free(phdr);
2421 tcc_free(s1->sym_attrs);
2422 return ret;
2423 }
2424
2425 LIBTCCAPI int tcc_output_file(TCCState *s, const char *filename)
2426 {
2427 int ret;
2428 #ifdef TCC_TARGET_PE
2429 if (s->output_type != TCC_OUTPUT_OBJ) {
2430 ret = pe_output_file(s, filename);
2431 } else
2432 #endif
2433 ret = elf_output_file(s, filename);
2434 return ret;
2435 }
2436
2437 static void *load_data(int fd, unsigned long file_offset, unsigned long size)
2438 {
2439 void *data;
2440
2441 data = tcc_malloc(size);
2442 lseek(fd, file_offset, SEEK_SET);
2443 read(fd, data, size);
2444 return data;
2445 }
2446
2447 typedef struct SectionMergeInfo {
2448 Section *s; /* corresponding existing section */
2449 unsigned long offset; /* offset of the new section in the existing section */
2450 uint8_t new_section; /* true if section 's' was added */
2451 uint8_t link_once; /* true if link once section */
2452 } SectionMergeInfo;
2453
2454 /* load an object file and merge it with current files */
2455 /* XXX: handle correctly stab (debug) info */
2456 ST_FUNC int tcc_load_object_file(TCCState *s1,
2457 int fd, unsigned long file_offset)
2458 {
2459 ElfW(Ehdr) ehdr;
2460 ElfW(Shdr) *shdr, *sh;
2461 int size, i, j, offset, offseti, nb_syms, sym_index, ret;
2462 unsigned char *strsec, *strtab;
2463 int *old_to_new_syms;
2464 char *sh_name, *name;
2465 SectionMergeInfo *sm_table, *sm;
2466 ElfW(Sym) *sym, *symtab;
2467 ElfW_Rel *rel;
2468 Section *s;
2469
2470 int stab_index;
2471 int stabstr_index;
2472
2473 stab_index = stabstr_index = 0;
2474
2475 if (read(fd, &ehdr, sizeof(ehdr)) != sizeof(ehdr))
2476 goto fail1;
2477 if (ehdr.e_ident[0] != ELFMAG0 ||
2478 ehdr.e_ident[1] != ELFMAG1 ||
2479 ehdr.e_ident[2] != ELFMAG2 ||
2480 ehdr.e_ident[3] != ELFMAG3)
2481 goto fail1;
2482 /* test if object file */
2483 if (ehdr.e_type != ET_REL)
2484 goto fail1;
2485 /* test CPU specific stuff */
2486 if (ehdr.e_ident[5] != ELFDATA2LSB ||
2487 ehdr.e_machine != EM_TCC_TARGET) {
2488 fail1:
2489 tcc_error_noabort("invalid object file");
2490 return -1;
2491 }
2492 /* read sections */
2493 shdr = load_data(fd, file_offset + ehdr.e_shoff,
2494 sizeof(ElfW(Shdr)) * ehdr.e_shnum);
2495 sm_table = tcc_mallocz(sizeof(SectionMergeInfo) * ehdr.e_shnum);
2496
2497 /* load section names */
2498 sh = &shdr[ehdr.e_shstrndx];
2499 strsec = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
2500
2501 /* load symtab and strtab */
2502 old_to_new_syms = NULL;
2503 symtab = NULL;
2504 strtab = NULL;
2505 nb_syms = 0;
2506 for(i = 1; i < ehdr.e_shnum; i++) {
2507 sh = &shdr[i];
2508 if (sh->sh_type == SHT_SYMTAB) {
2509 if (symtab) {
2510 tcc_error_noabort("object must contain only one symtab");
2511 fail:
2512 ret = -1;
2513 goto the_end;
2514 }
2515 nb_syms = sh->sh_size / sizeof(ElfW(Sym));
2516 symtab = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
2517 sm_table[i].s = symtab_section;
2518
2519 /* now load strtab */
2520 sh = &shdr[sh->sh_link];
2521 strtab = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
2522 }
2523 }
2524
2525 /* now examine each section and try to merge its content with the
2526 ones in memory */
2527 for(i = 1; i < ehdr.e_shnum; i++) {
2528 /* no need to examine section name strtab */
2529 if (i == ehdr.e_shstrndx)
2530 continue;
2531 sh = &shdr[i];
2532 sh_name = strsec + sh->sh_name;
2533 /* ignore sections types we do not handle */
2534 if (sh->sh_type != SHT_PROGBITS &&
2535 sh->sh_type != SHT_RELX &&
2536 #ifdef TCC_ARM_EABI
2537 sh->sh_type != SHT_ARM_EXIDX &&
2538 #endif
2539 sh->sh_type != SHT_NOBITS &&
2540 sh->sh_type != SHT_PREINIT_ARRAY &&
2541 sh->sh_type != SHT_INIT_ARRAY &&
2542 sh->sh_type != SHT_FINI_ARRAY &&
2543 strcmp(sh_name, ".stabstr")
2544 )
2545 continue;
2546 if (sh->sh_addralign < 1)
2547 sh->sh_addralign = 1;
2548 /* find corresponding section, if any */
2549 for(j = 1; j < s1->nb_sections;j++) {
2550 s = s1->sections[j];
2551 if (!strcmp(s->name, sh_name)) {
2552 if (!strncmp(sh_name, ".gnu.linkonce",
2553 sizeof(".gnu.linkonce") - 1)) {
2554 /* if a 'linkonce' section is already present, we
2555 do not add it again. It is a little tricky as
2556 symbols can still be defined in
2557 it. */
2558 sm_table[i].link_once = 1;
2559 goto next;
2560 } else {
2561 goto found;
2562 }
2563 }
2564 }
2565 /* not found: create new section */
2566 s = new_section(s1, sh_name, sh->sh_type, sh->sh_flags);
2567 /* take as much info as possible from the section. sh_link and
2568 sh_info will be updated later */
2569 s->sh_addralign = sh->sh_addralign;
2570 s->sh_entsize = sh->sh_entsize;
2571 sm_table[i].new_section = 1;
2572 found:
2573 if (sh->sh_type != s->sh_type) {
2574 tcc_error_noabort("invalid section type");
2575 goto fail;
2576 }
2577
2578 /* align start of section */
2579 offset = s->data_offset;
2580
2581 if (0 == strcmp(sh_name, ".stab")) {
2582 stab_index = i;
2583 goto no_align;
2584 }
2585 if (0 == strcmp(sh_name, ".stabstr")) {
2586 stabstr_index = i;
2587 goto no_align;
2588 }
2589
2590 size = sh->sh_addralign - 1;
2591 offset = (offset + size) & ~size;
2592 if (sh->sh_addralign > s->sh_addralign)
2593 s->sh_addralign = sh->sh_addralign;
2594 s->data_offset = offset;
2595 no_align:
2596 sm_table[i].offset = offset;
2597 sm_table[i].s = s;
2598 /* concatenate sections */
2599 size = sh->sh_size;
2600 if (sh->sh_type != SHT_NOBITS) {
2601 unsigned char *ptr;
2602 lseek(fd, file_offset + sh->sh_offset, SEEK_SET);
2603 ptr = section_ptr_add(s, size);
2604 read(fd, ptr, size);
2605 } else {
2606 s->data_offset += size;
2607 }
2608 next: ;
2609 }
2610
2611 /* gr relocate stab strings */
2612 if (stab_index && stabstr_index) {
2613 Stab_Sym *a, *b;
2614 unsigned o;
2615 s = sm_table[stab_index].s;
2616 a = (Stab_Sym *)(s->data + sm_table[stab_index].offset);
2617 b = (Stab_Sym *)(s->data + s->data_offset);
2618 o = sm_table[stabstr_index].offset;
2619 while (a < b)
2620 a->n_strx += o, a++;
2621 }
2622
2623 /* second short pass to update sh_link and sh_info fields of new
2624 sections */
2625 for(i = 1; i < ehdr.e_shnum; i++) {
2626 s = sm_table[i].s;
2627 if (!s || !sm_table[i].new_section)
2628 continue;
2629 sh = &shdr[i];
2630 if (sh->sh_link > 0)
2631 s->link = sm_table[sh->sh_link].s;
2632 if (sh->sh_type == SHT_RELX) {
2633 s->sh_info = sm_table[sh->sh_info].s->sh_num;
2634 /* update backward link */
2635 s1->sections[s->sh_info]->reloc = s;
2636 }
2637 }
2638 sm = sm_table;
2639
2640 /* resolve symbols */
2641 old_to_new_syms = tcc_mallocz(nb_syms * sizeof(int));
2642
2643 sym = symtab + 1;
2644 for(i = 1; i < nb_syms; i++, sym++) {
2645 if (sym->st_shndx != SHN_UNDEF &&
2646 sym->st_shndx < SHN_LORESERVE) {
2647 sm = &sm_table[sym->st_shndx];
2648 if (sm->link_once) {
2649 /* if a symbol is in a link once section, we use the
2650 already defined symbol. It is very important to get
2651 correct relocations */
2652 if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
2653 name = strtab + sym->st_name;
2654 sym_index = find_elf_sym(symtab_section, name);
2655 if (sym_index)
2656 old_to_new_syms[i] = sym_index;
2657 }
2658 continue;
2659 }
2660 /* if no corresponding section added, no need to add symbol */
2661 if (!sm->s)
2662 continue;
2663 /* convert section number */
2664 sym->st_shndx = sm->s->sh_num;
2665 /* offset value */
2666 sym->st_value += sm->offset;
2667 }
2668 /* add symbol */
2669 name = strtab + sym->st_name;
2670 sym_index = add_elf_sym(symtab_section, sym->st_value, sym->st_size,
2671 sym->st_info, sym->st_other,
2672 sym->st_shndx, name);
2673 old_to_new_syms[i] = sym_index;
2674 }
2675
2676 /* third pass to patch relocation entries */
2677 for(i = 1; i < ehdr.e_shnum; i++) {
2678 s = sm_table[i].s;
2679 if (!s)
2680 continue;
2681 sh = &shdr[i];
2682 offset = sm_table[i].offset;
2683 switch(s->sh_type) {
2684 case SHT_RELX:
2685 /* take relocation offset information */
2686 offseti = sm_table[sh->sh_info].offset;
2687 for_each_elem(s, (offset / sizeof(*rel)), rel, ElfW_Rel) {
2688 int type;
2689 unsigned sym_index;
2690 /* convert symbol index */
2691 type = ELFW(R_TYPE)(rel->r_info);
2692 sym_index = ELFW(R_SYM)(rel->r_info);
2693 /* NOTE: only one symtab assumed */
2694 if (sym_index >= nb_syms)
2695 goto invalid_reloc;
2696 sym_index = old_to_new_syms[sym_index];
2697 /* ignore link_once in rel section. */
2698 if (!sym_index && !sm->link_once
2699 #ifdef TCC_TARGET_ARM
2700 && type != R_ARM_V4BX
2701 #endif
2702 ) {
2703 invalid_reloc:
2704 tcc_error_noabort("Invalid relocation entry [%2d] '%s' @ %.8x",
2705 i, strsec + sh->sh_name, rel->r_offset);
2706 goto fail;
2707 }
2708 rel->r_info = ELFW(R_INFO)(sym_index, type);
2709 /* offset the relocation offset */
2710 rel->r_offset += offseti;
2711 #ifdef TCC_TARGET_ARM
2712 /* Jumps and branches from a Thumb code to a PLT entry need
2713 special handling since PLT entries are ARM code.
2714 Unconditional bl instructions referencing PLT entries are
2715 handled by converting these instructions into blx
2716 instructions. Other case of instructions referencing a PLT
2717 entry require to add a Thumb stub before the PLT entry to
2718 switch to ARM mode. We set bit plt_thumb_stub of the
2719 attribute of a symbol to indicate such a case. */
2720 if (type == R_ARM_THM_JUMP24)
2721 alloc_sym_attr(s1, sym_index)->plt_thumb_stub = 1;
2722 #endif
2723 }
2724 break;
2725 default:
2726 break;
2727 }
2728 }
2729
2730 ret = 0;
2731 the_end:
2732 tcc_free(symtab);
2733 tcc_free(strtab);
2734 tcc_free(old_to_new_syms);
2735 tcc_free(sm_table);
2736 tcc_free(strsec);
2737 tcc_free(shdr);
2738 return ret;
2739 }
2740
2741 typedef struct ArchiveHeader {
2742 char ar_name[16]; /* name of this member */
2743 char ar_date[12]; /* file mtime */
2744 char ar_uid[6]; /* owner uid; printed as decimal */
2745 char ar_gid[6]; /* owner gid; printed as decimal */
2746 char ar_mode[8]; /* file mode, printed as octal */
2747 char ar_size[10]; /* file size, printed as decimal */
2748 char ar_fmag[2]; /* should contain ARFMAG */
2749 } ArchiveHeader;
2750
2751 static int get_be32(const uint8_t *b)
2752 {
2753 return b[3] | (b[2] << 8) | (b[1] << 16) | (b[0] << 24);
2754 }
2755
2756 /* load only the objects which resolve undefined symbols */
2757 static int tcc_load_alacarte(TCCState *s1, int fd, int size)
2758 {
2759 int i, bound, nsyms, sym_index, off, ret;
2760 uint8_t *data;
2761 const char *ar_names, *p;
2762 const uint8_t *ar_index;
2763 ElfW(Sym) *sym;
2764
2765 data = tcc_malloc(size);
2766 if (read(fd, data, size) != size)
2767 goto fail;
2768 nsyms = get_be32(data);
2769 ar_index = data + 4;
2770 ar_names = ar_index + nsyms * 4;
2771
2772 do {
2773 bound = 0;
2774 for(p = ar_names, i = 0; i < nsyms; i++, p += strlen(p)+1) {
2775 sym_index = find_elf_sym(symtab_section, p);
2776 if(sym_index) {
2777 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
2778 if(sym->st_shndx == SHN_UNDEF) {
2779 off = get_be32(ar_index + i * 4) + sizeof(ArchiveHeader);
2780 ++bound;
2781 lseek(fd, off, SEEK_SET);
2782 if(tcc_load_object_file(s1, fd, off) < 0) {
2783 fail:
2784 ret = -1;
2785 goto the_end;
2786 }
2787 }
2788 }
2789 }
2790 } while(bound);
2791 ret = 0;
2792 the_end:
2793 tcc_free(data);
2794 return ret;
2795 }
2796
2797 /* load a '.a' file */
2798 ST_FUNC int tcc_load_archive(TCCState *s1, int fd)
2799 {
2800 ArchiveHeader hdr;
2801 char ar_size[11];
2802 char ar_name[17];
2803 char magic[8];
2804 int size, len, i;
2805 unsigned long file_offset;
2806
2807 /* skip magic which was already checked */
2808 read(fd, magic, sizeof(magic));
2809
2810 for(;;) {
2811 len = read(fd, &hdr, sizeof(hdr));
2812 if (len == 0)
2813 break;
2814 if (len != sizeof(hdr)) {
2815 tcc_error_noabort("invalid archive");
2816 return -1;
2817 }
2818 memcpy(ar_size, hdr.ar_size, sizeof(hdr.ar_size));
2819 ar_size[sizeof(hdr.ar_size)] = '\0';
2820 size = strtol(ar_size, NULL, 0);
2821 memcpy(ar_name, hdr.ar_name, sizeof(hdr.ar_name));
2822 for(i = sizeof(hdr.ar_name) - 1; i >= 0; i--) {
2823 if (ar_name[i] != ' ')
2824 break;
2825 }
2826 ar_name[i + 1] = '\0';
2827 file_offset = lseek(fd, 0, SEEK_CUR);
2828 /* align to even */
2829 size = (size + 1) & ~1;
2830 if (!strcmp(ar_name, "/")) {
2831 /* coff symbol table : we handle it */
2832 if(s1->alacarte_link)
2833 return tcc_load_alacarte(s1, fd, size);
2834 } else if (!strcmp(ar_name, "//") ||
2835 !strcmp(ar_name, "__.SYMDEF") ||
2836 !strcmp(ar_name, "__.SYMDEF/") ||
2837 !strcmp(ar_name, "ARFILENAMES/")) {
2838 /* skip symbol table or archive names */
2839 } else {
2840 if (tcc_load_object_file(s1, fd, file_offset) < 0)
2841 return -1;
2842 }
2843 lseek(fd, file_offset + size, SEEK_SET);
2844 }
2845 return 0;
2846 }
2847
2848 #ifndef TCC_TARGET_PE
2849 /* load a DLL and all referenced DLLs. 'level = 0' means that the DLL
2850 is referenced by the user (so it should be added as DT_NEEDED in
2851 the generated ELF file) */
2852 ST_FUNC int tcc_load_dll(TCCState *s1, int fd, const char *filename, int level)
2853 {
2854 ElfW(Ehdr) ehdr;
2855 ElfW(Shdr) *shdr, *sh, *sh1;
2856 int i, j, nb_syms, nb_dts, sym_bind, ret;
2857 ElfW(Sym) *sym, *dynsym;
2858 ElfW(Dyn) *dt, *dynamic;
2859 unsigned char *dynstr;
2860 const char *name, *soname;
2861 DLLReference *dllref;
2862
2863 read(fd, &ehdr, sizeof(ehdr));
2864
2865 /* test CPU specific stuff */
2866 if (ehdr.e_ident[5] != ELFDATA2LSB ||
2867 ehdr.e_machine != EM_TCC_TARGET) {
2868 tcc_error_noabort("bad architecture");
2869 return -1;
2870 }
2871
2872 /* read sections */
2873 shdr = load_data(fd, ehdr.e_shoff, sizeof(ElfW(Shdr)) * ehdr.e_shnum);
2874
2875 /* load dynamic section and dynamic symbols */
2876 nb_syms = 0;
2877 nb_dts = 0;
2878 dynamic = NULL;
2879 dynsym = NULL; /* avoid warning */
2880 dynstr = NULL; /* avoid warning */
2881 for(i = 0, sh = shdr; i < ehdr.e_shnum; i++, sh++) {
2882 switch(sh->sh_type) {
2883 case SHT_DYNAMIC:
2884 nb_dts = sh->sh_size / sizeof(ElfW(Dyn));
2885 dynamic = load_data(fd, sh->sh_offset, sh->sh_size);
2886 break;
2887 case SHT_DYNSYM:
2888 nb_syms = sh->sh_size / sizeof(ElfW(Sym));
2889 dynsym = load_data(fd, sh->sh_offset, sh->sh_size);
2890 sh1 = &shdr[sh->sh_link];
2891 dynstr = load_data(fd, sh1->sh_offset, sh1->sh_size);
2892 break;
2893 default:
2894 break;
2895 }
2896 }
2897
2898 /* compute the real library name */
2899 soname = tcc_basename(filename);
2900
2901 for(i = 0, dt = dynamic; i < nb_dts; i++, dt++) {
2902 if (dt->d_tag == DT_SONAME) {
2903 soname = dynstr + dt->d_un.d_val;
2904 }
2905 }
2906
2907 /* if the dll is already loaded, do not load it */
2908 for(i = 0; i < s1->nb_loaded_dlls; i++) {
2909 dllref = s1->loaded_dlls[i];
2910 if (!strcmp(soname, dllref->name)) {
2911 /* but update level if needed */
2912 if (level < dllref->level)
2913 dllref->level = level;
2914 ret = 0;
2915 goto the_end;
2916 }
2917 }
2918
2919 /* add the dll and its level */
2920 dllref = tcc_mallocz(sizeof(DLLReference) + strlen(soname));
2921 dllref->level = level;
2922 strcpy(dllref->name, soname);
2923 dynarray_add((void ***)&s1->loaded_dlls, &s1->nb_loaded_dlls, dllref);
2924
2925 /* add dynamic symbols in dynsym_section */
2926 for(i = 1, sym = dynsym + 1; i < nb_syms; i++, sym++) {
2927 sym_bind = ELFW(ST_BIND)(sym->st_info);
2928 if (sym_bind == STB_LOCAL)
2929 continue;
2930 name = dynstr + sym->st_name;
2931 add_elf_sym(s1->dynsymtab_section, sym->st_value, sym->st_size,
2932 sym->st_info, sym->st_other, sym->st_shndx, name);
2933 }
2934
2935 /* load all referenced DLLs */
2936 for(i = 0, dt = dynamic; i < nb_dts; i++, dt++) {
2937 switch(dt->d_tag) {
2938 case DT_NEEDED:
2939 name = dynstr + dt->d_un.d_val;
2940 for(j = 0; j < s1->nb_loaded_dlls; j++) {
2941 dllref = s1->loaded_dlls[j];
2942 if (!strcmp(name, dllref->name))
2943 goto already_loaded;
2944 }
2945 if (tcc_add_dll(s1, name, AFF_REFERENCED_DLL) < 0) {
2946 tcc_error_noabort("referenced dll '%s' not found", name);
2947 ret = -1;
2948 goto the_end;
2949 }
2950 already_loaded:
2951 break;
2952 }
2953 }
2954 ret = 0;
2955 the_end:
2956 tcc_free(dynstr);
2957 tcc_free(dynsym);
2958 tcc_free(dynamic);
2959 tcc_free(shdr);
2960 return ret;
2961 }
2962
2963 #define LD_TOK_NAME 256
2964 #define LD_TOK_EOF (-1)
2965
2966 /* return next ld script token */
2967 static int ld_next(TCCState *s1, char *name, int name_size)
2968 {
2969 int c;
2970 char *q;
2971
2972 redo:
2973 switch(ch) {
2974 case ' ':
2975 case '\t':
2976 case '\f':
2977 case '\v':
2978 case '\r':
2979 case '\n':
2980 inp();
2981 goto redo;
2982 case '/':
2983 minp();
2984 if (ch == '*') {
2985 file->buf_ptr = parse_comment(file->buf_ptr);
2986 ch = file->buf_ptr[0];
2987 goto redo;
2988 } else {
2989 q = name;
2990 *q++ = '/';
2991 goto parse_name;
2992 }
2993 break;
2994 /* case 'a' ... 'z': */
2995 case 'a':
2996 case 'b':
2997 case 'c':
2998 case 'd':
2999 case 'e':
3000 case 'f':
3001 case 'g':
3002 case 'h':
3003 case 'i':
3004 case 'j':
3005 case 'k':
3006 case 'l':
3007 case 'm':
3008 case 'n':
3009 case 'o':
3010 case 'p':
3011 case 'q':
3012 case 'r':
3013 case 's':
3014 case 't':
3015 case 'u':
3016 case 'v':
3017 case 'w':
3018 case 'x':
3019 case 'y':
3020 case 'z':
3021 /* case 'A' ... 'z': */
3022 case 'A':
3023 case 'B':
3024 case 'C':
3025 case 'D':
3026 case 'E':
3027 case 'F':
3028 case 'G':
3029 case 'H':
3030 case 'I':
3031 case 'J':
3032 case 'K':
3033 case 'L':
3034 case 'M':
3035 case 'N':
3036 case 'O':
3037 case 'P':
3038 case 'Q':
3039 case 'R':
3040 case 'S':
3041 case 'T':
3042 case 'U':
3043 case 'V':
3044 case 'W':
3045 case 'X':
3046 case 'Y':
3047 case 'Z':
3048 case '_':
3049 case '\\':
3050 case '.':
3051 case '$':
3052 case '~':
3053 q = name;
3054 parse_name:
3055 for(;;) {
3056 if (!((ch >= 'a' && ch <= 'z') ||
3057 (ch >= 'A' && ch <= 'Z') ||
3058 (ch >= '0' && ch <= '9') ||
3059 strchr("/.-_+=$:\\,~", ch)))
3060 break;
3061 if ((q - name) < name_size - 1) {
3062 *q++ = ch;
3063 }
3064 minp();
3065 }
3066 *q = '\0';
3067 c = LD_TOK_NAME;
3068 break;
3069 case CH_EOF:
3070 c = LD_TOK_EOF;
3071 break;
3072 default:
3073 c = ch;
3074 inp();
3075 break;
3076 }
3077 return c;
3078 }
3079
3080 static int ld_add_file(TCCState *s1, const char filename[])
3081 {
3082 int ret;
3083
3084 ret = tcc_add_file_internal(s1, filename, 0);
3085 if (ret)
3086 ret = tcc_add_dll(s1, filename, 0);
3087 return ret;
3088 }
3089
3090 static inline int new_undef_syms(void)
3091 {
3092 int ret = 0;
3093 ret = new_undef_sym;
3094 new_undef_sym = 0;
3095 return ret;
3096 }
3097
3098 static int ld_add_file_list(TCCState *s1, const char *cmd, int as_needed)
3099 {
3100 char filename[1024], libname[1024];
3101 int t, group, nblibs = 0, ret = 0;
3102 char **libs = NULL;
3103
3104 group = !strcmp(cmd, "GROUP");
3105 if (!as_needed)
3106 new_undef_syms();
3107 t = ld_next(s1, filename, sizeof(filename));
3108 if (t != '(')
3109 expect("(");
3110 t = ld_next(s1, filename, sizeof(filename));
3111 for(;;) {
3112 libname[0] = '\0';
3113 if (t == LD_TOK_EOF) {
3114 tcc_error_noabort("unexpected end of file");
3115 ret = -1;
3116 goto lib_parse_error;
3117 } else if (t == ')') {
3118 break;
3119 } else if (t == '-') {
3120 t = ld_next(s1, filename, sizeof(filename));
3121 if ((t != LD_TOK_NAME) || (filename[0] != 'l')) {
3122 tcc_error_noabort("library name expected");
3123 ret = -1;
3124 goto lib_parse_error;
3125 }
3126 pstrcpy(libname, sizeof libname, &filename[1]);
3127 if (s1->static_link) {
3128 snprintf(filename, sizeof filename, "lib%s.a", libname);
3129 } else {
3130 snprintf(filename, sizeof filename, "lib%s.so", libname);
3131 }
3132 } else if (t != LD_TOK_NAME) {
3133 tcc_error_noabort("filename expected");
3134 ret = -1;
3135 goto lib_parse_error;
3136 }
3137 if (!strcmp(filename, "AS_NEEDED")) {
3138 ret = ld_add_file_list(s1, cmd, 1);
3139 if (ret)
3140 goto lib_parse_error;
3141 } else {
3142 /* TODO: Implement AS_NEEDED support. Ignore it for now */
3143 if (!as_needed) {
3144 ret = ld_add_file(s1, filename);
3145 if (ret)
3146 goto lib_parse_error;
3147 if (group) {
3148 /* Add the filename *and* the libname to avoid future conversions */
3149 dynarray_add((void ***) &libs, &nblibs, tcc_strdup(filename));
3150 if (libname[0] != '\0')
3151 dynarray_add((void ***) &libs, &nblibs, tcc_strdup(libname));
3152 }
3153 }
3154 }
3155 t = ld_next(s1, filename, sizeof(filename));
3156 if (t == ',') {
3157 t = ld_next(s1, filename, sizeof(filename));
3158 }
3159 }
3160 if (group && !as_needed) {
3161 while (new_undef_syms()) {
3162 int i;
3163
3164 for (i = 0; i < nblibs; i ++)
3165 ld_add_file(s1, libs[i]);
3166 }
3167 }
3168 lib_parse_error:
3169 dynarray_reset(&libs, &nblibs);
3170 return ret;
3171 }
3172
3173 /* interpret a subset of GNU ldscripts to handle the dummy libc.so
3174 files */
3175 ST_FUNC int tcc_load_ldscript(TCCState *s1)
3176 {
3177 char cmd[64];
3178 char filename[1024];
3179 int t, ret;
3180
3181 ch = file->buf_ptr[0];
3182 ch = handle_eob();
3183 for(;;) {
3184 t = ld_next(s1, cmd, sizeof(cmd));
3185 if (t == LD_TOK_EOF)
3186 return 0;
3187 else if (t != LD_TOK_NAME)
3188 return -1;
3189 if (!strcmp(cmd, "INPUT") ||
3190 !strcmp(cmd, "GROUP")) {
3191 ret = ld_add_file_list(s1, cmd, 0);
3192 if (ret)
3193 return ret;
3194 } else if (!strcmp(cmd, "OUTPUT_FORMAT") ||
3195 !strcmp(cmd, "TARGET")) {
3196 /* ignore some commands */
3197 t = ld_next(s1, cmd, sizeof(cmd));
3198 if (t != '(')
3199 expect("(");
3200 for(;;) {
3201 t = ld_next(s1, filename, sizeof(filename));
3202 if (t == LD_TOK_EOF) {
3203 tcc_error_noabort("unexpected end of file");
3204 return -1;
3205 } else if (t == ')') {
3206 break;
3207 }
3208 }
3209 } else {
3210 return -1;
3211 }
3212 }
3213 return 0;
3214 }
3215 #endif /* !TCC_TARGET_PE */
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