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New implementation of va_list/va_start/var_copy that do not use dynamic memory, with...
[tinycc.git] / tccelf.c
blob45c0265ad892ee3cd712513c04c05534d9a0e0a1
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 unsigned 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((unsigned char *) 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((unsigned char *) 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 = (char *) 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 = (char *) 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 = (char *) 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, need_plt_entry, got_entry_present = 0;
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 need_plt_entry = s1->dynsym &&
1021 #ifdef TCC_TARGET_X86_64
1022 (reloc_type == R_X86_64_JUMP_SLOT);
1023 #elif defined(TCC_TARGET_I386)
1024 (reloc_type == R_386_JMP_SLOT);
1025 #elif defined(TCC_TARGET_ARM)
1026 (reloc_type == R_ARM_JUMP_SLOT);
1027 #else
1028 0;
1029 #endif
1030
1031 /* if a got entry already exists for that symbol, no need to add one */
1032 if (sym_index < s1->nb_sym_attrs &&
1033 s1->sym_attrs[sym_index].got_offset) {
1034 if (!need_plt_entry)
1035 return;
1036 else
1037 got_entry_present = 1;
1038 }
1039
1040 alloc_sym_attr(s1, sym_index)->got_offset = s1->got->data_offset;
1041
1042 if (s1->dynsym) {
1043 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1044 name = (char *) symtab_section->link->data + sym->st_name;
1045 if (s1->sym_attrs[sym_index].has_plt_entry)
1046 return;
1047 s1->sym_attrs[sym_index].has_plt_entry = 1;
1048 offset = sym->st_value;
1049 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
1050 if (need_plt_entry) {
1051 Section *plt;
1052 uint8_t *p;
1053 int modrm;
1054
1055 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1056 modrm = 0x25;
1057 #else
1058 /* if we build a DLL, we add a %ebx offset */
1059 if (s1->output_type == TCC_OUTPUT_DLL)
1060 modrm = 0xa3;
1061 else
1062 modrm = 0x25;
1063 #endif
1064
1065 /* add a PLT entry */
1066 plt = s1->plt;
1067 if (plt->data_offset == 0) {
1068 /* first plt entry */
1069 p = section_ptr_add(plt, 16);
1070 p[0] = 0xff; /* pushl got + PTR_SIZE */
1071 p[1] = modrm + 0x10;
1072 put32(p + 2, PTR_SIZE);
1073 p[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */
1074 p[7] = modrm;
1075 put32(p + 8, PTR_SIZE * 2);
1076 }
1077
1078 p = section_ptr_add(plt, 16);
1079 p[0] = 0xff; /* jmp *(got + x) */
1080 p[1] = modrm;
1081 put32(p + 2, s1->got->data_offset);
1082 p[6] = 0x68; /* push $xxx */
1083 put32(p + 7, (plt->data_offset - 32) >> 1);
1084 p[11] = 0xe9; /* jmp plt_start */
1085 put32(p + 12, -(plt->data_offset));
1086
1087 /* the symbol is modified so that it will be relocated to
1088 the PLT */
1089 #if !defined(TCC_OUTPUT_DLL_WITH_PLT)
1090 if (s1->output_type == TCC_OUTPUT_EXE)
1091 #endif
1092 offset = plt->data_offset - 16;
1093 }
1094 #elif defined(TCC_TARGET_ARM)
1095 if (need_plt_entry) {
1096 Section *plt;
1097 uint8_t *p;
1098
1099 /* if we build a DLL, we add a %ebx offset */
1100 if (s1->output_type == TCC_OUTPUT_DLL)
1101 tcc_error("DLLs unimplemented!");
1102
1103 /* add a PLT entry */
1104 plt = s1->plt;
1105 if (plt->data_offset == 0) {
1106 /* first plt entry */
1107 p = section_ptr_add(plt, 16);
1108 put32(p, 0xe52de004); /* push {lr} */
1109 put32(p+4, 0xe59fe010); /* ldr lr, [pc, #16] */
1110 put32(p+8, 0xe08fe00e); /* add lr, pc, lr */
1111 put32(p+12, 0xe5bef008); /* ldr pc, [lr, #8]! */
1112 }
1113
1114 if (s1->sym_attrs[sym_index].plt_thumb_stub) {
1115 p = section_ptr_add(plt, 20);
1116 put32(p, 0x4778); /* bx pc */
1117 put32(p+2, 0x46c0); /* nop */
1118 p += 4;
1119 } else
1120 p = section_ptr_add(plt, 16);
1121 put32(p, 0xe59fc004); /* ldr ip, [pc, #4] ; GOT entry offset */
1122 put32(p+4, 0xe08fc00c); /* add ip, pc, ip ; addr of GOT entry */
1123 put32(p+8, 0xe59cf000); /* ldr pc, [ip] ; jump to GOT entry */
1124 put32(p+12, s1->got->data_offset); /* GOT entry off once patched */
1125
1126 /* the symbol is modified so that it will be relocated to
1127 the PLT */
1128 if (s1->output_type == TCC_OUTPUT_EXE)
1129 offset = plt->data_offset - 16;
1130 }
1131 #elif defined(TCC_TARGET_C67)
1132 tcc_error("C67 got not implemented");
1133 #else
1134 #error unsupported CPU
1135 #endif
1136 index = put_elf_sym(s1->dynsym, offset,
1137 size, info, 0, sym->st_shndx, name);
1138 if (got_entry_present) {
1139 put_elf_reloc(s1->dynsym, s1->got,
1140 s1->sym_attrs[sym_index].got_offset,
1141 reloc_type, index);
1142 return;
1143 }
1144
1145 /* put a got entry */
1146 put_elf_reloc(s1->dynsym, s1->got,
1147 s1->got->data_offset,
1148 reloc_type, index);
1149 }
1150 ptr = section_ptr_add(s1->got, PTR_SIZE);
1151 *ptr = 0;
1152 }
1153
1154 /* build GOT and PLT entries */
1155 ST_FUNC void build_got_entries(TCCState *s1)
1156 {
1157 Section *s;
1158 ElfW_Rel *rel;
1159 ElfW(Sym) *sym;
1160 int i, type, reloc_type, sym_index;
1161
1162 for(i = 1; i < s1->nb_sections; i++) {
1163 s = s1->sections[i];
1164 if (s->sh_type != SHT_RELX)
1165 continue;
1166 /* no need to handle got relocations */
1167 if (s->link != symtab_section)
1168 continue;
1169 for_each_elem(s, 0, rel, ElfW_Rel) {
1170 type = ELFW(R_TYPE)(rel->r_info);
1171 switch(type) {
1172 #if defined(TCC_TARGET_I386)
1173 case R_386_GOT32:
1174 case R_386_GOTOFF:
1175 case R_386_GOTPC:
1176 case R_386_PLT32:
1177 if (!s1->got)
1178 build_got(s1);
1179 if (type == R_386_GOT32 || type == R_386_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_386_GOT32)
1184 reloc_type = R_386_GLOB_DAT;
1185 else
1186 reloc_type = R_386_JMP_SLOT;
1187 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1188 sym_index);
1189 }
1190 break;
1191 #elif defined(TCC_TARGET_ARM)
1192 case R_ARM_GOT32:
1193 case R_ARM_GOTOFF:
1194 case R_ARM_GOTPC:
1195 case R_ARM_PLT32:
1196 if (!s1->got)
1197 build_got(s1);
1198 if (type == R_ARM_GOT32 || type == R_ARM_PLT32) {
1199 sym_index = ELFW(R_SYM)(rel->r_info);
1200 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1201 /* look at the symbol got offset. If none, then add one */
1202 if (type == R_ARM_GOT32)
1203 reloc_type = R_ARM_GLOB_DAT;
1204 else
1205 reloc_type = R_ARM_JUMP_SLOT;
1206 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1207 sym_index);
1208 }
1209 break;
1210 case R_ARM_THM_JUMP24:
1211 sym_index = ELFW(R_SYM)(rel->r_info);
1212 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1213 /* We are relocating a jump from thumb code to arm code */
1214 if (sym->st_shndx != SHN_UNDEF && !(sym->st_value & 1)) {
1215 int index;
1216 uint8_t *p;
1217 char *name, buf[1024];
1218 Section *text_section;
1219
1220 name = (char *) symtab_section->link->data + sym->st_name;
1221 text_section = s1->sections[sym->st_shndx];
1222 /* Modify reloc to target a thumb stub to switch to ARM */
1223 snprintf(buf, sizeof(buf), "%s_from_thumb", name);
1224 index = put_elf_sym(symtab_section,
1225 text_section->data_offset + 1,
1226 sym->st_size, sym->st_info, 0,
1227 sym->st_shndx, buf);
1228 rel->r_info = ELFW(R_INFO)(index, type);
1229 /* Create a thumb stub fonction to switch to ARM mode */
1230 put_elf_reloc(symtab_section, text_section,
1231 text_section->data_offset + 4, R_ARM_JUMP24,
1232 sym_index);
1233 p = section_ptr_add(text_section, 8);
1234 put32(p, 0x4778); /* bx pc */
1235 put32(p+2, 0x46c0); /* nop */
1236 put32(p+4, 0xeafffffe); /* b $sym */
1237 }
1238 #elif defined(TCC_TARGET_C67)
1239 case R_C60_GOT32:
1240 case R_C60_GOTOFF:
1241 case R_C60_GOTPC:
1242 case R_C60_PLT32:
1243 if (!s1->got)
1244 build_got(s1);
1245 if (type == R_C60_GOT32 || type == R_C60_PLT32) {
1246 sym_index = ELFW(R_SYM)(rel->r_info);
1247 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1248 /* look at the symbol got offset. If none, then add one */
1249 if (type == R_C60_GOT32)
1250 reloc_type = R_C60_GLOB_DAT;
1251 else
1252 reloc_type = R_C60_JMP_SLOT;
1253 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1254 sym_index);
1255 }
1256 break;
1257 #elif defined(TCC_TARGET_X86_64)
1258 case R_X86_64_GOT32:
1259 case R_X86_64_GOTTPOFF:
1260 case R_X86_64_GOTPCREL:
1261 case R_X86_64_PLT32:
1262 if (!s1->got)
1263 build_got(s1);
1264 if (type == R_X86_64_GOT32 || type == R_X86_64_GOTPCREL ||
1265 type == R_X86_64_PLT32) {
1266 sym_index = ELFW(R_SYM)(rel->r_info);
1267 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1268 /* look at the symbol got offset. If none, then add one */
1269 if (type == R_X86_64_GOT32 || type == R_X86_64_GOTPCREL)
1270 reloc_type = R_X86_64_GLOB_DAT;
1271 else
1272 reloc_type = R_X86_64_JUMP_SLOT;
1273 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
1274 sym_index);
1275 }
1276 break;
1277 #else
1278 #error unsupported CPU
1279 #endif
1280 default:
1281 break;
1282 }
1283 }
1284 }
1285 }
1286
1287 ST_FUNC Section *new_symtab(TCCState *s1,
1288 const char *symtab_name, int sh_type, int sh_flags,
1289 const char *strtab_name,
1290 const char *hash_name, int hash_sh_flags)
1291 {
1292 Section *symtab, *strtab, *hash;
1293 int *ptr, nb_buckets;
1294
1295 symtab = new_section(s1, symtab_name, sh_type, sh_flags);
1296 symtab->sh_entsize = sizeof(ElfW(Sym));
1297 strtab = new_section(s1, strtab_name, SHT_STRTAB, sh_flags);
1298 put_elf_str(strtab, "");
1299 symtab->link = strtab;
1300 put_elf_sym(symtab, 0, 0, 0, 0, 0, NULL);
1301
1302 nb_buckets = 1;
1303
1304 hash = new_section(s1, hash_name, SHT_HASH, hash_sh_flags);
1305 hash->sh_entsize = sizeof(int);
1306 symtab->hash = hash;
1307 hash->link = symtab;
1308
1309 ptr = section_ptr_add(hash, (2 + nb_buckets + 1) * sizeof(int));
1310 ptr[0] = nb_buckets;
1311 ptr[1] = 1;
1312 memset(ptr + 2, 0, (nb_buckets + 1) * sizeof(int));
1313 return symtab;
1314 }
1315
1316 /* put dynamic tag */
1317 static void put_dt(Section *dynamic, int dt, addr_t val)
1318 {
1319 ElfW(Dyn) *dyn;
1320 dyn = section_ptr_add(dynamic, sizeof(ElfW(Dyn)));
1321 dyn->d_tag = dt;
1322 dyn->d_un.d_val = val;
1323 }
1324
1325 static void add_init_array_defines(TCCState *s1, const char *section_name)
1326 {
1327 Section *s;
1328 long end_offset;
1329 char sym_start[1024];
1330 char sym_end[1024];
1331
1332 snprintf(sym_start, sizeof(sym_start), "__%s_start", section_name + 1);
1333 snprintf(sym_end, sizeof(sym_end), "__%s_end", section_name + 1);
1334
1335 s = find_section(s1, section_name);
1336 if (!s) {
1337 end_offset = 0;
1338 s = data_section;
1339 } else {
1340 end_offset = s->data_offset;
1341 }
1342
1343 add_elf_sym(symtab_section,
1344 0, 0,
1345 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1346 s->sh_num, sym_start);
1347 add_elf_sym(symtab_section,
1348 end_offset, 0,
1349 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1350 s->sh_num, sym_end);
1351 }
1352
1353 ST_FUNC void tcc_add_bcheck(TCCState *s1)
1354 {
1355 #ifdef CONFIG_TCC_BCHECK
1356 unsigned long *ptr;
1357 Section *init_section;
1358 unsigned char *pinit;
1359 int sym_index;
1360
1361 if (0 == s1->do_bounds_check)
1362 return;
1363
1364 /* XXX: add an object file to do that */
1365 ptr = section_ptr_add(bounds_section, sizeof(unsigned long));
1366 *ptr = 0;
1367 add_elf_sym(symtab_section, 0, 0,
1368 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1369 bounds_section->sh_num, "__bounds_start");
1370 #ifdef TCC_TARGET_I386
1371 if (s1->output_type != TCC_OUTPUT_MEMORY) {
1372 /* add 'call __bound_init()' in .init section */
1373 init_section = find_section(s1, ".init");
1374 pinit = section_ptr_add(init_section, 5);
1375 pinit[0] = 0xe8;
1376 put32(pinit + 1, -4);
1377 sym_index = find_elf_sym(symtab_section, "__bound_init");
1378 put_elf_reloc(symtab_section, init_section,
1379 init_section->data_offset - 4, R_386_PC32, sym_index);
1380 }
1381 #endif
1382 #endif
1383 }
1384
1385 static inline int tcc_add_support(TCCState *s1, const char *filename)
1386 {
1387 char buf[1024];
1388 snprintf(buf, sizeof(buf), "%s/%s", s1->tcc_lib_path, filename);
1389 return tcc_add_file(s1, buf);
1390 }
1391
1392 /* add tcc runtime libraries */
1393 ST_FUNC void tcc_add_runtime(TCCState *s1)
1394 {
1395 /* add libc */
1396 if (!s1->nostdlib) {
1397 tcc_add_library(s1, "c");
1398 #ifdef CONFIG_USE_LIBGCC
1399 if (!s1->static_link) {
1400 tcc_add_file(s1, TCC_LIBGCC);
1401 tcc_add_support(s1, "libtcc1.a");
1402 } else
1403 tcc_add_support(s1, "libtcc1.a");
1404 #else
1405 tcc_add_support(s1, "libtcc1.a");
1406 #endif
1407 }
1408
1409 /* tcc_add_bcheck tries to relocate a call to __bound_init in _init so
1410 libtcc1.a must be loaded before for __bound_init to be defined and
1411 crtn.o must be loaded after to not finalize _init too early. */
1412 tcc_add_bcheck(s1);
1413
1414 if (!s1->nostdlib) {
1415 /* add crt end if not memory output */
1416 if (s1->output_type != TCC_OUTPUT_MEMORY)
1417 tcc_add_crt(s1, "crtn.o");
1418 }
1419 }
1420
1421 /* add various standard linker symbols (must be done after the
1422 sections are filled (for example after allocating common
1423 symbols)) */
1424 ST_FUNC void tcc_add_linker_symbols(TCCState *s1)
1425 {
1426 char buf[1024];
1427 int i;
1428 Section *s;
1429
1430 add_elf_sym(symtab_section,
1431 text_section->data_offset, 0,
1432 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1433 text_section->sh_num, "_etext");
1434 add_elf_sym(symtab_section,
1435 data_section->data_offset, 0,
1436 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1437 data_section->sh_num, "_edata");
1438 add_elf_sym(symtab_section,
1439 bss_section->data_offset, 0,
1440 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1441 bss_section->sh_num, "_end");
1442 /* horrible new standard ldscript defines */
1443 add_init_array_defines(s1, ".preinit_array");
1444 add_init_array_defines(s1, ".init_array");
1445 add_init_array_defines(s1, ".fini_array");
1446
1447 /* add start and stop symbols for sections whose name can be
1448 expressed in C */
1449 for(i = 1; i < s1->nb_sections; i++) {
1450 s = s1->sections[i];
1451 if (s->sh_type == SHT_PROGBITS &&
1452 (s->sh_flags & SHF_ALLOC)) {
1453 const char *p;
1454 int ch;
1455
1456 /* check if section name can be expressed in C */
1457 p = s->name;
1458 for(;;) {
1459 ch = *p;
1460 if (!ch)
1461 break;
1462 if (!isid(ch) && !isnum(ch))
1463 goto next_sec;
1464 p++;
1465 }
1466 snprintf(buf, sizeof(buf), "__start_%s", s->name);
1467 add_elf_sym(symtab_section,
1468 0, 0,
1469 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1470 s->sh_num, buf);
1471 snprintf(buf, sizeof(buf), "__stop_%s", s->name);
1472 add_elf_sym(symtab_section,
1473 s->data_offset, 0,
1474 ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
1475 s->sh_num, buf);
1476 }
1477 next_sec: ;
1478 }
1479 }
1480
1481 static void tcc_output_binary(TCCState *s1, FILE *f,
1482 const int *sec_order)
1483 {
1484 Section *s;
1485 int i, offset, size;
1486
1487 offset = 0;
1488 for(i=1;i<s1->nb_sections;i++) {
1489 s = s1->sections[sec_order[i]];
1490 if (s->sh_type != SHT_NOBITS &&
1491 (s->sh_flags & SHF_ALLOC)) {
1492 while (offset < s->sh_offset) {
1493 fputc(0, f);
1494 offset++;
1495 }
1496 size = s->sh_size;
1497 fwrite(s->data, 1, size, f);
1498 offset += size;
1499 }
1500 }
1501 }
1502
1503 #if 1 // this allow valgrind to work on linux //defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1504 #define HAVE_PHDR 1
1505 #define EXTRA_RELITEMS 14
1506
1507 /* move the relocation value from .dynsym to .got */
1508 void patch_dynsym_undef(TCCState *s1, Section *s)
1509 {
1510 uint32_t *gotd = (void *)s1->got->data;
1511 ElfW(Sym) *sym;
1512
1513 gotd += 3; /* dummy entries in .got */
1514 /* relocate symbols in .dynsym */
1515 for_each_elem(s, 1, sym, ElfW(Sym)) {
1516 if (sym->st_shndx == SHN_UNDEF) {
1517 *gotd++ = sym->st_value + 6; /* XXX 6 is magic ? */
1518 sym->st_value = 0;
1519 }
1520 }
1521 }
1522 #else
1523 #define HAVE_PHDR 0
1524 #define EXTRA_RELITEMS 9
1525
1526 /* zero plt offsets of weak symbols in .dynsym */
1527 void patch_dynsym_undef(TCCState *s1, Section *s)
1528 {
1529 ElfW(Sym) *sym;
1530
1531 for_each_elem(s, 1, sym, ElfW(Sym))
1532 if (sym->st_shndx == SHN_UNDEF && ELFW(ST_BIND)(sym->st_info) == STB_WEAK)
1533 sym->st_value = 0;
1534 }
1535 #endif
1536
1537 ST_FUNC void fill_got_entry(TCCState *s1, ElfW_Rel *rel)
1538 {
1539 int sym_index = ELFW(R_SYM) (rel->r_info);
1540 ElfW(Sym) *sym = &((ElfW(Sym) *) symtab_section->data)[sym_index];
1541 unsigned long offset;
1542
1543 if (sym_index >= s1->nb_sym_attrs)
1544 return;
1545 offset = s1->sym_attrs[sym_index].got_offset;
1546 section_reserve(s1->got, offset + PTR_SIZE);
1547 #ifdef TCC_TARGET_X86_64
1548 /* only works for x86-64 */
1549 put32(s1->got->data + offset + 4, sym->st_value >> 32);
1550 #endif
1551 put32(s1->got->data + offset, sym->st_value & 0xffffffff);
1552 }
1553
1554 /* Perform relocation to GOT or PLT entries */
1555 ST_FUNC void fill_got(TCCState *s1)
1556 {
1557 Section *s;
1558 ElfW_Rel *rel;
1559 int i;
1560
1561 for(i = 1; i < s1->nb_sections; i++) {
1562 s = s1->sections[i];
1563 if (s->sh_type != SHT_RELX)
1564 continue;
1565 /* no need to handle got relocations */
1566 if (s->link != symtab_section)
1567 continue;
1568 for_each_elem(s, 0, rel, ElfW_Rel) {
1569 switch (ELFW(R_TYPE) (rel->r_info)) {
1570 case R_X86_64_GOT32:
1571 case R_X86_64_GOTPCREL:
1572 case R_X86_64_PLT32:
1573 fill_got_entry(s1, rel);
1574 break;
1575 }
1576 }
1577 }
1578 }
1579
1580 /* Bind symbols of executable: resolve undefined symbols from exported symbols
1581 in shared libraries and export non local defined symbols to shared libraries
1582 if -rdynamic switch was given on command line */
1583 static void bind_exe_dynsyms(TCCState *s1)
1584 {
1585 const char *name;
1586 int sym_index, index;
1587 ElfW(Sym) *sym, *esym;
1588 int type;
1589
1590 /* Resolve undefined symbols from dynamic symbols. When there is a match:
1591 - if STT_FUNC or STT_GNU_IFUNC symbol -> add it in PLT
1592 - if STT_OBJECT symbol -> add it in .bss section with suitable reloc */
1593 for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
1594 if (sym->st_shndx == SHN_UNDEF) {
1595 name = (char *) symtab_section->link->data + sym->st_name;
1596 sym_index = find_elf_sym(s1->dynsymtab_section, name);
1597 if (sym_index) {
1598 esym = &((ElfW(Sym) *)s1->dynsymtab_section->data)[sym_index];
1599 type = ELFW(ST_TYPE)(esym->st_info);
1600 if ((type == STT_FUNC) || (type == STT_GNU_IFUNC)) {
1601 /* Indirect functions shall have STT_FUNC type in executable
1602 * dynsym section. Indeed, a dlsym call following a lazy
1603 * resolution would pick the symbol value from the
1604 * executable dynsym entry which would contain the address
1605 * of the function wanted by the caller of dlsym instead of
1606 * the address of the function that would return that
1607 * address */
1608 put_got_entry(s1, R_JMP_SLOT, esym->st_size,
1609 ELFW(ST_INFO)(STB_GLOBAL,STT_FUNC),
1610 sym - (ElfW(Sym) *)symtab_section->data);
1611 } else if (type == STT_OBJECT) {
1612 unsigned long offset;
1613 ElfW(Sym) *dynsym;
1614 offset = bss_section->data_offset;
1615 /* XXX: which alignment ? */
1616 offset = (offset + 16 - 1) & -16;
1617 index = put_elf_sym(s1->dynsym, offset, esym->st_size,
1618 esym->st_info, 0, bss_section->sh_num,
1619 name);
1620 /* Ensure R_COPY works for weak symbol aliases */
1621 if (ELFW(ST_BIND)(esym->st_info) == STB_WEAK) {
1622 for_each_elem(s1->dynsymtab_section, 1, dynsym, ElfW(Sym)) {
1623 if ((dynsym->st_value == esym->st_value)
1624 && (ELFW(ST_BIND)(dynsym->st_info) == STB_GLOBAL)) {
1625 char *dynname = (char *) s1->dynsymtab_section->link->data
1626 + dynsym->st_name;
1627 put_elf_sym(s1->dynsym, offset, dynsym->st_size,
1628 dynsym->st_info, 0,
1629 bss_section->sh_num, dynname);
1630 break;
1631 }
1632 }
1633 }
1634 put_elf_reloc(s1->dynsym, bss_section,
1635 offset, R_COPY, index);
1636 offset += esym->st_size;
1637 bss_section->data_offset = offset;
1638 }
1639 } else {
1640 /* STB_WEAK undefined symbols are accepted */
1641 /* XXX: _fp_hw seems to be part of the ABI, so we ignore it */
1642 if (ELFW(ST_BIND)(sym->st_info) == STB_WEAK ||
1643 !strcmp(name, "_fp_hw")) {
1644 } else {
1645 tcc_error_noabort("undefined symbol '%s'", name);
1646 }
1647 }
1648 } else if (s1->rdynamic && ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
1649 /* if -rdynamic option, then export all non local symbols */
1650 name = (char *) symtab_section->link->data + sym->st_name;
1651 put_elf_sym(s1->dynsym, sym->st_value, sym->st_size, sym->st_info,
1652 0, sym->st_shndx, name);
1653 }
1654 }
1655 }
1656
1657 /* Bind symbols of libraries: export non local symbols of executable that
1658 resolve undefined symbols of shared libraries */
1659 static void bind_libs_dynsyms(TCCState *s1)
1660 {
1661 const char *name;
1662 int sym_index;
1663 ElfW(Sym) *sym, *esym;
1664
1665 /* now look at unresolved dynamic symbols and export
1666 corresponding symbol */
1667 for_each_elem(s1->dynsymtab_section, 1, esym, ElfW(Sym)) {
1668 if (esym->st_shndx == SHN_UNDEF) {
1669 name = (char *) s1->dynsymtab_section->link->data + esym->st_name;
1670 sym_index = find_elf_sym(symtab_section, name);
1671 if (sym_index) {
1672 /* XXX: avoid adding a symbol if already present because of
1673 -rdynamic ? */
1674 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
1675 put_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
1676 sym->st_info, 0, sym->st_shndx, name);
1677 } else {
1678 /* weak symbols can stay undefined */
1679 if (ELFW(ST_BIND)(esym->st_info) != STB_WEAK)
1680 tcc_warning("undefined dynamic symbol '%s'", name);
1681 }
1682 }
1683 }
1684 }
1685
1686 /* Export all non local symbols (for shared libraries) */
1687 static void export_global_syms(TCCState *s1)
1688 {
1689 int nb_syms, dynindex, index;
1690 const char *name;
1691 ElfW(Sym) *sym;
1692
1693 nb_syms = symtab_section->data_offset / sizeof(ElfW(Sym));
1694 s1->symtab_to_dynsym = tcc_mallocz(sizeof(int) * nb_syms);
1695 for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
1696 if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
1697 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1698 int type = ELFW(ST_TYPE)(sym->st_info);
1699 if ((type == STT_FUNC || type == STT_GNU_IFUNC)
1700 && sym->st_shndx == SHN_UNDEF) {
1701 int visibility = ELFW(ST_BIND)(sym->st_info);
1702 put_got_entry(s1, R_JMP_SLOT, sym->st_size,
1703 ELFW(ST_INFO)(visibility, STT_FUNC),
1704 sym - (ElfW(Sym) *) symtab_section->data);
1705 } else if (type == STT_OBJECT) {
1706 put_got_entry(s1, R_X86_64_GLOB_DAT, sym->st_size, sym->st_info,
1707 sym - (ElfW(Sym) *) symtab_section->data);
1708 } else
1709 #endif
1710 {
1711 name = (char *) symtab_section->link->data + sym->st_name;
1712 dynindex = put_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
1713 sym->st_info, 0, sym->st_shndx, name);
1714 index = sym - (ElfW(Sym) *) symtab_section->data;
1715 s1->symtab_to_dynsym[index] = dynindex;
1716 }
1717 }
1718 }
1719 }
1720
1721 /* relocate the PLT: compute addresses and offsets in the PLT now that final
1722 address for PLT and GOT are known (see fill_program_header) */
1723 static void relocate_plt(TCCState *s1)
1724 {
1725 uint8_t *p, *p_end;
1726
1727 p = s1->plt->data;
1728 p_end = p + s1->plt->data_offset;
1729 if (p < p_end) {
1730 #if defined(TCC_TARGET_I386)
1731 put32(p + 2, get32(p + 2) + s1->got->sh_addr);
1732 put32(p + 8, get32(p + 8) + s1->got->sh_addr);
1733 p += 16;
1734 while (p < p_end) {
1735 put32(p + 2, get32(p + 2) + s1->got->sh_addr);
1736 p += 16;
1737 }
1738 #elif defined(TCC_TARGET_X86_64)
1739 int x = s1->got->sh_addr - s1->plt->sh_addr - 6;
1740 put32(p + 2, get32(p + 2) + x);
1741 put32(p + 8, get32(p + 8) + x - 6);
1742 p += 16;
1743 while (p < p_end) {
1744 put32(p + 2, get32(p + 2) + x + s1->plt->data - p);
1745 p += 16;
1746 }
1747 #elif defined(TCC_TARGET_ARM)
1748 int x;
1749 x=s1->got->sh_addr - s1->plt->sh_addr - 12;
1750 p += 16;
1751 while (p < p_end) {
1752 if (get32(p) == 0x46c04778) /* PLT Thumb stub present */
1753 p += 4;
1754 put32(p + 12, x + get32(p + 12) + s1->plt->data - p);
1755 p += 16;
1756 }
1757 #elif defined(TCC_TARGET_C67)
1758 /* XXX: TODO */
1759 #else
1760 #error unsupported CPU
1761 #endif
1762 }
1763 }
1764
1765 /* Allocate strings for section names and decide if an unallocated section
1766 should be output.
1767
1768 NOTE: the strsec section comes last, so its size is also correct ! */
1769 static void alloc_sec_names(TCCState *s1, int file_type, Section *strsec)
1770 {
1771 int i;
1772 Section *s;
1773
1774 /* Allocate strings for section names */
1775 for(i = 1; i < s1->nb_sections; i++) {
1776 s = s1->sections[i];
1777 s->sh_name = put_elf_str(strsec, s->name);
1778 /* when generating a DLL, we include relocations but we may
1779 patch them */
1780 if (file_type == TCC_OUTPUT_DLL &&
1781 s->sh_type == SHT_RELX &&
1782 !(s->sh_flags & SHF_ALLOC)) {
1783 /* gr: avoid bogus relocs for empty (debug) sections */
1784 if (s1->sections[s->sh_info]->sh_flags & SHF_ALLOC)
1785 prepare_dynamic_rel(s1, s);
1786 else if (s1->do_debug)
1787 s->sh_size = s->data_offset;
1788 } else if (s1->do_debug ||
1789 file_type == TCC_OUTPUT_OBJ ||
1790 (s->sh_flags & SHF_ALLOC) ||
1791 i == (s1->nb_sections - 1)) {
1792 /* we output all sections if debug or object file */
1793 s->sh_size = s->data_offset;
1794 }
1795 }
1796 }
1797
1798 /* Info to be copied in dynamic section */
1799 struct dyn_inf {
1800 Section *dynamic;
1801 Section *dynstr;
1802 unsigned long dyn_rel_off;
1803 addr_t rel_addr;
1804 addr_t rel_size;
1805 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1806 addr_t bss_addr;
1807 addr_t bss_size;
1808 #endif
1809 };
1810
1811 /* Assign sections to segments and decide how are sections laid out when loaded
1812 in memory. This function also fills corresponding program headers. */
1813 static int layout_sections(TCCState *s1, ElfW(Phdr) *phdr, int phnum,
1814 Section *interp, struct dyn_inf *dyninf,
1815 int *sec_order)
1816 {
1817 int i, j, k, file_type, sh_order_index, file_offset;
1818 long long tmp;
1819 addr_t addr;
1820 ElfW(Phdr) *ph;
1821 Section *s;
1822
1823 file_type = s1->output_type;
1824 sh_order_index = 1;
1825 if (s1->output_format == TCC_OUTPUT_FORMAT_ELF)
1826 file_offset = sizeof(ElfW(Ehdr)) + phnum * sizeof(ElfW(Phdr));
1827 else
1828 file_offset = 0;
1829
1830 if (phnum > 0) {
1831 if (s1->has_text_addr) {
1832 int a_offset, p_offset;
1833 addr = s1->text_addr;
1834 /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
1835 ELF_PAGE_SIZE */
1836 a_offset = (int) (addr & (s1->section_align - 1));
1837 p_offset = file_offset & (s1->section_align - 1);
1838 if (a_offset < p_offset)
1839 a_offset += s1->section_align;
1840 file_offset += (a_offset - p_offset);
1841 } else {
1842 if (file_type == TCC_OUTPUT_DLL)
1843 addr = 0;
1844 else
1845 addr = ELF_START_ADDR;
1846 /* compute address after headers */
1847 addr += (file_offset & (s1->section_align - 1));
1848 }
1849
1850 ph = &phdr[0];
1851 /* Leave one program headers for the program interpreter and one for
1852 the program header table itself if needed. These are done later as
1853 they require section layout to be done first. */
1854 if (interp)
1855 ph += 1 + HAVE_PHDR;
1856
1857 /* dynamic relocation table information, for .dynamic section */
1858 dyninf->rel_addr = dyninf->rel_size = 0;
1859 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1860 dyninf->bss_addr = dyninf->bss_size = 0;
1861 #endif
1862
1863 for(j = 0; j < 2; j++) {
1864 ph->p_type = PT_LOAD;
1865 if (j == 0)
1866 ph->p_flags = PF_R | PF_X;
1867 else
1868 ph->p_flags = PF_R | PF_W;
1869 ph->p_align = s1->section_align;
1870
1871 /* Decide the layout of sections loaded in memory. This must
1872 be done before program headers are filled since they contain
1873 info about the layout. We do the following ordering: interp,
1874 symbol tables, relocations, progbits, nobits */
1875 /* XXX: do faster and simpler sorting */
1876 for(k = 0; k < 5; k++) {
1877 for(i = 1; i < s1->nb_sections; i++) {
1878 s = s1->sections[i];
1879 /* compute if section should be included */
1880 if (j == 0) {
1881 if ((s->sh_flags & (SHF_ALLOC | SHF_WRITE)) !=
1882 SHF_ALLOC)
1883 continue;
1884 } else {
1885 if ((s->sh_flags & (SHF_ALLOC | SHF_WRITE)) !=
1886 (SHF_ALLOC | SHF_WRITE))
1887 continue;
1888 }
1889 if (s == interp) {
1890 if (k != 0)
1891 continue;
1892 } else if (s->sh_type == SHT_DYNSYM ||
1893 s->sh_type == SHT_STRTAB ||
1894 s->sh_type == SHT_HASH) {
1895 if (k != 1)
1896 continue;
1897 } else if (s->sh_type == SHT_RELX) {
1898 if (k != 2)
1899 continue;
1900 } else if (s->sh_type == SHT_NOBITS) {
1901 if (k != 4)
1902 continue;
1903 } else {
1904 if (k != 3)
1905 continue;
1906 }
1907 sec_order[sh_order_index++] = i;
1908
1909 /* section matches: we align it and add its size */
1910 tmp = addr;
1911 addr = (addr + s->sh_addralign - 1) &
1912 ~(s->sh_addralign - 1);
1913 file_offset += (int) ( addr - tmp );
1914 s->sh_offset = file_offset;
1915 s->sh_addr = addr;
1916
1917 /* update program header infos */
1918 if (ph->p_offset == 0) {
1919 ph->p_offset = file_offset;
1920 ph->p_vaddr = addr;
1921 ph->p_paddr = ph->p_vaddr;
1922 }
1923 /* update dynamic relocation infos */
1924 if (s->sh_type == SHT_RELX) {
1925 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1926 if (!strcmp(strsec->data + s->sh_name, ".rel.got")) {
1927 dyninf->rel_addr = addr;
1928 dyninf->rel_size += s->sh_size; /* XXX only first rel. */
1929 }
1930 if (!strcmp(strsec->data + s->sh_name, ".rel.bss")) {
1931 dyninf->bss_addr = addr;
1932 dyninf->bss_size = s->sh_size; /* XXX only first rel. */
1933 }
1934 #else
1935 if (dyninf->rel_size == 0)
1936 dyninf->rel_addr = addr;
1937 dyninf->rel_size += s->sh_size;
1938 #endif
1939 }
1940 addr += s->sh_size;
1941 if (s->sh_type != SHT_NOBITS)
1942 file_offset += s->sh_size;
1943 }
1944 }
1945 ph->p_filesz = file_offset - ph->p_offset;
1946 ph->p_memsz = addr - ph->p_vaddr;
1947 ph++;
1948 if (j == 0) {
1949 if (s1->output_format == TCC_OUTPUT_FORMAT_ELF) {
1950 /* if in the middle of a page, we duplicate the page in
1951 memory so that one copy is RX and the other is RW */
1952 if ((addr & (s1->section_align - 1)) != 0)
1953 addr += s1->section_align;
1954 } else {
1955 addr = (addr + s1->section_align - 1) & ~(s1->section_align - 1);
1956 file_offset = (file_offset + s1->section_align - 1) &
1957 ~(s1->section_align - 1);
1958 }
1959 }
1960 }
1961 }
1962
1963 /* all other sections come after */
1964 for(i = 1; i < s1->nb_sections; i++) {
1965 s = s1->sections[i];
1966 if (phnum > 0 && (s->sh_flags & SHF_ALLOC))
1967 continue;
1968 sec_order[sh_order_index++] = i;
1969
1970 file_offset = (file_offset + s->sh_addralign - 1) &
1971 ~(s->sh_addralign - 1);
1972 s->sh_offset = file_offset;
1973 if (s->sh_type != SHT_NOBITS)
1974 file_offset += s->sh_size;
1975 }
1976
1977 return file_offset;
1978 }
1979
1980 static void fill_unloadable_phdr(ElfW(Phdr) *phdr, int phnum, Section *interp,
1981 Section *dynamic)
1982 {
1983 ElfW(Phdr) *ph;
1984
1985 /* if interpreter, then add corresponding program header */
1986 if (interp) {
1987 ph = &phdr[0];
1988
1989 if (HAVE_PHDR)
1990 {
1991 int len = phnum * sizeof(ElfW(Phdr));
1992
1993 ph->p_type = PT_PHDR;
1994 ph->p_offset = sizeof(ElfW(Ehdr));
1995 ph->p_vaddr = interp->sh_addr - len;
1996 ph->p_paddr = ph->p_vaddr;
1997 ph->p_filesz = ph->p_memsz = len;
1998 ph->p_flags = PF_R | PF_X;
1999 ph->p_align = 4; /* interp->sh_addralign; */
2000 ph++;
2001 }
2002
2003 ph->p_type = PT_INTERP;
2004 ph->p_offset = interp->sh_offset;
2005 ph->p_vaddr = interp->sh_addr;
2006 ph->p_paddr = ph->p_vaddr;
2007 ph->p_filesz = interp->sh_size;
2008 ph->p_memsz = interp->sh_size;
2009 ph->p_flags = PF_R;
2010 ph->p_align = interp->sh_addralign;
2011 }
2012
2013 /* if dynamic section, then add corresponding program header */
2014 if (dynamic) {
2015 ph = &phdr[phnum - 1];
2016
2017 ph->p_type = PT_DYNAMIC;
2018 ph->p_offset = dynamic->sh_offset;
2019 ph->p_vaddr = dynamic->sh_addr;
2020 ph->p_paddr = ph->p_vaddr;
2021 ph->p_filesz = dynamic->sh_size;
2022 ph->p_memsz = dynamic->sh_size;
2023 ph->p_flags = PF_R | PF_W;
2024 ph->p_align = dynamic->sh_addralign;
2025 }
2026 }
2027
2028 /* Fill the dynamic section with tags describing the address and size of
2029 sections */
2030 static void fill_dynamic(TCCState *s1, struct dyn_inf *dyninf)
2031 {
2032 Section *dynamic;
2033
2034 dynamic = dyninf->dynamic;
2035
2036 /* put dynamic section entries */
2037 dynamic->data_offset = dyninf->dyn_rel_off;
2038 put_dt(dynamic, DT_HASH, s1->dynsym->hash->sh_addr);
2039 put_dt(dynamic, DT_STRTAB, dyninf->dynstr->sh_addr);
2040 put_dt(dynamic, DT_SYMTAB, s1->dynsym->sh_addr);
2041 put_dt(dynamic, DT_STRSZ, dyninf->dynstr->data_offset);
2042 put_dt(dynamic, DT_SYMENT, sizeof(ElfW(Sym)));
2043 #ifdef TCC_TARGET_X86_64
2044 put_dt(dynamic, DT_RELA, dyninf->rel_addr);
2045 put_dt(dynamic, DT_RELASZ, dyninf->rel_size);
2046 put_dt(dynamic, DT_RELAENT, sizeof(ElfW_Rel));
2047 #else
2048 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2049 put_dt(dynamic, DT_PLTGOT, s1->got->sh_addr);
2050 put_dt(dynamic, DT_PLTRELSZ, dyninf->rel_size);
2051 put_dt(dynamic, DT_JMPREL, dyninf->rel_addr);
2052 put_dt(dynamic, DT_PLTREL, DT_REL);
2053 put_dt(dynamic, DT_REL, dyninf->bss_addr);
2054 put_dt(dynamic, DT_RELSZ, dyninf->bss_size);
2055 #else
2056 put_dt(dynamic, DT_REL, dyninf->rel_addr);
2057 put_dt(dynamic, DT_RELSZ, dyninf->rel_size);
2058 put_dt(dynamic, DT_RELENT, sizeof(ElfW_Rel));
2059 #endif
2060 #endif
2061 if (s1->do_debug)
2062 put_dt(dynamic, DT_DEBUG, 0);
2063 put_dt(dynamic, DT_NULL, 0);
2064 }
2065
2066 /* Relocate remaining sections and symbols (that is those not related to
2067 dynamic linking) */
2068 static int final_sections_reloc(TCCState *s1)
2069 {
2070 int i;
2071 Section *s;
2072
2073 relocate_syms(s1, 0);
2074
2075 if (s1->nb_errors != 0)
2076 return -1;
2077
2078 /* relocate sections */
2079 /* XXX: ignore sections with allocated relocations ? */
2080 for(i = 1; i < s1->nb_sections; i++) {
2081 s = s1->sections[i];
2082 if (s->reloc && s != s1->got)
2083 relocate_section(s1, s);
2084 }
2085
2086 /* relocate relocation entries if the relocation tables are
2087 allocated in the executable */
2088 for(i = 1; i < s1->nb_sections; i++) {
2089 s = s1->sections[i];
2090 if ((s->sh_flags & SHF_ALLOC) &&
2091 s->sh_type == SHT_RELX) {
2092 relocate_rel(s1, s);
2093 }
2094 }
2095 return 0;
2096 }
2097
2098 /* Create an ELF file on disk.
2099 This function handle ELF specific layout requirements */
2100 static void tcc_output_elf(TCCState *s1, FILE *f, int phnum, ElfW(Phdr) *phdr,
2101 int file_offset, int *sec_order)
2102 {
2103 int i, shnum, offset, size, file_type;
2104 Section *s;
2105 ElfW(Ehdr) ehdr;
2106 ElfW(Shdr) shdr, *sh;
2107
2108 file_type = s1->output_type;
2109 shnum = s1->nb_sections;
2110
2111 memset(&ehdr, 0, sizeof(ehdr));
2112
2113 if (phnum > 0) {
2114 ehdr.e_phentsize = sizeof(ElfW(Phdr));
2115 ehdr.e_phnum = phnum;
2116 ehdr.e_phoff = sizeof(ElfW(Ehdr));
2117 }
2118
2119 /* align to 4 */
2120 file_offset = (file_offset + 3) & -4;
2121
2122 /* fill header */
2123 ehdr.e_ident[0] = ELFMAG0;
2124 ehdr.e_ident[1] = ELFMAG1;
2125 ehdr.e_ident[2] = ELFMAG2;
2126 ehdr.e_ident[3] = ELFMAG3;
2127 ehdr.e_ident[4] = ELFCLASSW;
2128 ehdr.e_ident[5] = ELFDATA2LSB;
2129 ehdr.e_ident[6] = EV_CURRENT;
2130 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2131 ehdr.e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
2132 #endif
2133 #ifdef TCC_TARGET_ARM
2134 #ifdef TCC_ARM_EABI
2135 ehdr.e_ident[EI_OSABI] = 0;
2136 ehdr.e_flags = EF_ARM_EABI_VER4;
2137 if (file_type == TCC_OUTPUT_EXE || file_type == TCC_OUTPUT_DLL)
2138 ehdr.e_flags |= EF_ARM_HASENTRY;
2139 if (s1->float_abi == ARM_HARD_FLOAT)
2140 ehdr.e_flags |= EF_ARM_VFP_FLOAT;
2141 else
2142 ehdr.e_flags |= EF_ARM_SOFT_FLOAT;
2143 #else
2144 ehdr.e_ident[EI_OSABI] = ELFOSABI_ARM;
2145 #endif
2146 #endif
2147 switch(file_type) {
2148 default:
2149 case TCC_OUTPUT_EXE:
2150 ehdr.e_type = ET_EXEC;
2151 ehdr.e_entry = get_elf_sym_addr(s1, "_start", 1);
2152 break;
2153 case TCC_OUTPUT_DLL:
2154 ehdr.e_type = ET_DYN;
2155 ehdr.e_entry = text_section->sh_addr; /* XXX: is it correct ? */
2156 break;
2157 case TCC_OUTPUT_OBJ:
2158 ehdr.e_type = ET_REL;
2159 break;
2160 }
2161 ehdr.e_machine = EM_TCC_TARGET;
2162 ehdr.e_version = EV_CURRENT;
2163 ehdr.e_shoff = file_offset;
2164 ehdr.e_ehsize = sizeof(ElfW(Ehdr));
2165 ehdr.e_shentsize = sizeof(ElfW(Shdr));
2166 ehdr.e_shnum = shnum;
2167 ehdr.e_shstrndx = shnum - 1;
2168
2169 fwrite(&ehdr, 1, sizeof(ElfW(Ehdr)), f);
2170 fwrite(phdr, 1, phnum * sizeof(ElfW(Phdr)), f);
2171 offset = sizeof(ElfW(Ehdr)) + phnum * sizeof(ElfW(Phdr));
2172
2173 sort_syms(s1, symtab_section);
2174 for(i = 1; i < s1->nb_sections; i++) {
2175 s = s1->sections[sec_order[i]];
2176 if (s->sh_type != SHT_NOBITS) {
2177 if (s->sh_type == SHT_DYNSYM)
2178 patch_dynsym_undef(s1, s);
2179 while (offset < s->sh_offset) {
2180 fputc(0, f);
2181 offset++;
2182 }
2183 size = s->sh_size;
2184 fwrite(s->data, 1, size, f);
2185 offset += size;
2186 }
2187 }
2188
2189 /* output section headers */
2190 while (offset < ehdr.e_shoff) {
2191 fputc(0, f);
2192 offset++;
2193 }
2194
2195 for(i = 0; i < s1->nb_sections; i++) {
2196 sh = &shdr;
2197 memset(sh, 0, sizeof(ElfW(Shdr)));
2198 s = s1->sections[i];
2199 if (s) {
2200 sh->sh_name = s->sh_name;
2201 sh->sh_type = s->sh_type;
2202 sh->sh_flags = s->sh_flags;
2203 sh->sh_entsize = s->sh_entsize;
2204 sh->sh_info = s->sh_info;
2205 if (s->link)
2206 sh->sh_link = s->link->sh_num;
2207 sh->sh_addralign = s->sh_addralign;
2208 sh->sh_addr = s->sh_addr;
2209 sh->sh_offset = s->sh_offset;
2210 sh->sh_size = s->sh_size;
2211 }
2212 fwrite(sh, 1, sizeof(ElfW(Shdr)), f);
2213 }
2214 }
2215
2216 /* Write an elf, coff or "binary" file */
2217 static int tcc_write_elf_file(TCCState *s1, const char *filename, int phnum,
2218 ElfW(Phdr) *phdr, int file_offset, int *sec_order)
2219 {
2220 int fd, mode, file_type;
2221 FILE *f;
2222
2223 file_type = s1->output_type;
2224 if (file_type == TCC_OUTPUT_OBJ)
2225 mode = 0666;
2226 else
2227 mode = 0777;
2228 unlink(filename);
2229 fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, mode);
2230 if (fd < 0) {
2231 tcc_error_noabort("could not write '%s'", filename);
2232 return -1;
2233 }
2234 f = fdopen(fd, "wb");
2235 if (s1->verbose)
2236 printf("<- %s\n", filename);
2237
2238 #ifdef TCC_TARGET_COFF
2239 if (s1->output_format == TCC_OUTPUT_FORMAT_COFF)
2240 tcc_output_coff(s1, f);
2241 else
2242 #endif
2243 if (s1->output_format == TCC_OUTPUT_FORMAT_ELF)
2244 tcc_output_elf(s1, f, phnum, phdr, file_offset, sec_order);
2245 else
2246 tcc_output_binary(s1, f, sec_order);
2247 fclose(f);
2248
2249 return 0;
2250 }
2251
2252 /* Output an elf, coff or binary file */
2253 /* XXX: suppress unneeded sections */
2254 static int elf_output_file(TCCState *s1, const char *filename)
2255 {
2256 int i, ret, phnum, shnum, file_type, file_offset, *sec_order;
2257 struct dyn_inf dyninf;
2258 ElfW(Phdr) *phdr;
2259 ElfW(Sym) *sym;
2260 Section *strsec, *interp, *dynamic, *dynstr;
2261
2262 file_type = s1->output_type;
2263 s1->nb_errors = 0;
2264
2265 /* if linking, also link in runtime libraries (libc, libgcc, etc.) */
2266 if (file_type != TCC_OUTPUT_OBJ) {
2267 tcc_add_runtime(s1);
2268 }
2269
2270 phdr = NULL;
2271 sec_order = NULL;
2272 interp = dynamic = dynstr = NULL; /* avoid warning */
2273 dyninf.dyn_rel_off = 0; /* avoid warning */
2274
2275 if (file_type != TCC_OUTPUT_OBJ) {
2276 relocate_common_syms();
2277
2278 tcc_add_linker_symbols(s1);
2279
2280 if (!s1->static_link) {
2281 if (file_type == TCC_OUTPUT_EXE) {
2282 char *ptr;
2283 /* allow override the dynamic loader */
2284 const char *elfint = getenv("LD_SO");
2285 if (elfint == NULL)
2286 elfint = DEFAULT_ELFINTERP(s1);
2287 /* add interpreter section only if executable */
2288 interp = new_section(s1, ".interp", SHT_PROGBITS, SHF_ALLOC);
2289 interp->sh_addralign = 1;
2290 ptr = section_ptr_add(interp, 1 + strlen(elfint));
2291 strcpy(ptr, elfint);
2292 }
2293
2294 /* add dynamic symbol table */
2295 s1->dynsym = new_symtab(s1, ".dynsym", SHT_DYNSYM, SHF_ALLOC,
2296 ".dynstr",
2297 ".hash", SHF_ALLOC);
2298 dynstr = s1->dynsym->link;
2299
2300 /* add dynamic section */
2301 dynamic = new_section(s1, ".dynamic", SHT_DYNAMIC,
2302 SHF_ALLOC | SHF_WRITE);
2303 dynamic->link = dynstr;
2304 dynamic->sh_entsize = sizeof(ElfW(Dyn));
2305
2306 /* add PLT */
2307 s1->plt = new_section(s1, ".plt", SHT_PROGBITS,
2308 SHF_ALLOC | SHF_EXECINSTR);
2309 s1->plt->sh_entsize = 4;
2310
2311 build_got(s1);
2312
2313 if (file_type == TCC_OUTPUT_EXE) {
2314 bind_exe_dynsyms(s1);
2315
2316 if (s1->nb_errors) {
2317 ret = -1;
2318 goto the_end;
2319 }
2320
2321 bind_libs_dynsyms(s1);
2322 } else /* shared library case: simply export all global symbols */
2323 export_global_syms(s1);
2324
2325 build_got_entries(s1);
2326
2327 /* add a list of needed dlls */
2328 for(i = 0; i < s1->nb_loaded_dlls; i++) {
2329 DLLReference *dllref = s1->loaded_dlls[i];
2330 if (dllref->level == 0)
2331 put_dt(dynamic, DT_NEEDED, put_elf_str(dynstr, dllref->name));
2332 }
2333
2334 if (s1->rpath)
2335 put_dt(dynamic, DT_RPATH, put_elf_str(dynstr, s1->rpath));
2336
2337 /* XXX: currently, since we do not handle PIC code, we
2338 must relocate the readonly segments */
2339 if (file_type == TCC_OUTPUT_DLL) {
2340 if (s1->soname)
2341 put_dt(dynamic, DT_SONAME, put_elf_str(dynstr, s1->soname));
2342 put_dt(dynamic, DT_TEXTREL, 0);
2343 }
2344
2345 if (s1->symbolic)
2346 put_dt(dynamic, DT_SYMBOLIC, 0);
2347
2348 /* add necessary space for other entries */
2349 dyninf.dyn_rel_off = dynamic->data_offset;
2350 dynamic->data_offset += sizeof(ElfW(Dyn)) * EXTRA_RELITEMS;
2351 } else {
2352 /* still need to build got entries in case of static link */
2353 build_got_entries(s1);
2354 }
2355 }
2356
2357 /* we add a section for symbols */
2358 strsec = new_section(s1, ".shstrtab", SHT_STRTAB, 0);
2359 put_elf_str(strsec, "");
2360
2361 /* compute number of sections */
2362 shnum = s1->nb_sections;
2363
2364 /* this array is used to reorder sections in the output file */
2365 sec_order = tcc_malloc(sizeof(int) * shnum);
2366 sec_order[0] = 0;
2367
2368 /* compute number of program headers */
2369 switch(file_type) {
2370 default:
2371 case TCC_OUTPUT_OBJ:
2372 phnum = 0;
2373 break;
2374 case TCC_OUTPUT_EXE:
2375 if (!s1->static_link)
2376 phnum = 4 + HAVE_PHDR;
2377 else
2378 phnum = 2;
2379 break;
2380 case TCC_OUTPUT_DLL:
2381 phnum = 3;
2382 break;
2383 }
2384
2385 /* Allocate strings for section names */
2386 alloc_sec_names(s1, file_type, strsec);
2387
2388 /* allocate program segment headers */
2389 phdr = tcc_mallocz(phnum * sizeof(ElfW(Phdr)));
2390
2391 /* compute section to program header mapping */
2392 file_offset = layout_sections(s1, phdr, phnum, interp, &dyninf, sec_order);
2393
2394 /* Fill remaining program header and finalize relocation related to dynamic
2395 linking. */
2396 if (phnum > 0) {
2397 fill_unloadable_phdr(phdr, phnum, interp, dynamic);
2398 if (dynamic) {
2399 dyninf.dynamic = dynamic;
2400 dyninf.dynstr = dynstr;
2401
2402 fill_dynamic(s1, &dyninf);
2403
2404 /* put in GOT the dynamic section address and relocate PLT */
2405 put32(s1->got->data, dynamic->sh_addr);
2406 if (file_type == TCC_OUTPUT_EXE
2407 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
2408 || file_type == TCC_OUTPUT_DLL
2409 #endif
2410 )
2411 relocate_plt(s1);
2412
2413 /* relocate symbols in .dynsym now that final addresses are known */
2414 for_each_elem(s1->dynsym, 1, sym, ElfW(Sym)) {
2415 /* relocate to PLT if symbol corresponds to a PLT entry */
2416 if (sym->st_shndx == SHN_UNDEF) {
2417 if (sym->st_value)
2418 sym->st_value += s1->plt->sh_addr;
2419 } else if (sym->st_shndx < SHN_LORESERVE) {
2420 /* do symbol relocation */
2421 sym->st_value += s1->sections[sym->st_shndx]->sh_addr;
2422 }
2423 }
2424 }
2425 }
2426
2427 /* if building executable or DLL, then relocate each section
2428 except the GOT which is already relocated */
2429 if (file_type != TCC_OUTPUT_OBJ) {
2430 ret = final_sections_reloc(s1);
2431 if (ret)
2432 goto the_end;
2433 }
2434
2435 /* Perform relocation to GOT or PLT entries */
2436 if (file_type == TCC_OUTPUT_EXE && s1->static_link)
2437 fill_got(s1);
2438
2439 /* Create the ELF file with name 'filename' */
2440 ret = tcc_write_elf_file(s1, filename, phnum, phdr, file_offset, sec_order);
2441 the_end:
2442 tcc_free(s1->symtab_to_dynsym);
2443 tcc_free(sec_order);
2444 tcc_free(phdr);
2445 tcc_free(s1->sym_attrs);
2446 s1->sym_attrs = NULL;
2447 return ret;
2448 }
2449
2450 LIBTCCAPI int tcc_output_file(TCCState *s, const char *filename)
2451 {
2452 int ret;
2453 #ifdef TCC_TARGET_PE
2454 if (s->output_type != TCC_OUTPUT_OBJ) {
2455 ret = pe_output_file(s, filename);
2456 } else
2457 #endif
2458 ret = elf_output_file(s, filename);
2459 return ret;
2460 }
2461
2462 static void *load_data(int fd, unsigned long file_offset, unsigned long size)
2463 {
2464 void *data;
2465
2466 data = tcc_malloc(size);
2467 lseek(fd, file_offset, SEEK_SET);
2468 read(fd, data, size);
2469 return data;
2470 }
2471
2472 typedef struct SectionMergeInfo {
2473 Section *s; /* corresponding existing section */
2474 unsigned long offset; /* offset of the new section in the existing section */
2475 uint8_t new_section; /* true if section 's' was added */
2476 uint8_t link_once; /* true if link once section */
2477 } SectionMergeInfo;
2478
2479 /* load an object file and merge it with current files */
2480 /* XXX: handle correctly stab (debug) info */
2481 ST_FUNC int tcc_load_object_file(TCCState *s1,
2482 int fd, unsigned long file_offset)
2483 {
2484 ElfW(Ehdr) ehdr;
2485 ElfW(Shdr) *shdr, *sh;
2486 int size, i, j, offset, offseti, nb_syms, sym_index, ret;
2487 unsigned char *strsec, *strtab;
2488 int *old_to_new_syms;
2489 char *sh_name, *name;
2490 SectionMergeInfo *sm_table, *sm;
2491 ElfW(Sym) *sym, *symtab;
2492 ElfW_Rel *rel;
2493 Section *s;
2494
2495 int stab_index;
2496 int stabstr_index;
2497
2498 stab_index = stabstr_index = 0;
2499
2500 if (read(fd, &ehdr, sizeof(ehdr)) != sizeof(ehdr))
2501 goto fail1;
2502 if (ehdr.e_ident[0] != ELFMAG0 ||
2503 ehdr.e_ident[1] != ELFMAG1 ||
2504 ehdr.e_ident[2] != ELFMAG2 ||
2505 ehdr.e_ident[3] != ELFMAG3)
2506 goto fail1;
2507 /* test if object file */
2508 if (ehdr.e_type != ET_REL)
2509 goto fail1;
2510 /* test CPU specific stuff */
2511 if (ehdr.e_ident[5] != ELFDATA2LSB ||
2512 ehdr.e_machine != EM_TCC_TARGET) {
2513 fail1:
2514 tcc_error_noabort("invalid object file");
2515 return -1;
2516 }
2517 /* read sections */
2518 shdr = load_data(fd, file_offset + ehdr.e_shoff,
2519 sizeof(ElfW(Shdr)) * ehdr.e_shnum);
2520 sm_table = tcc_mallocz(sizeof(SectionMergeInfo) * ehdr.e_shnum);
2521
2522 /* load section names */
2523 sh = &shdr[ehdr.e_shstrndx];
2524 strsec = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
2525
2526 /* load symtab and strtab */
2527 old_to_new_syms = NULL;
2528 symtab = NULL;
2529 strtab = NULL;
2530 nb_syms = 0;
2531 for(i = 1; i < ehdr.e_shnum; i++) {
2532 sh = &shdr[i];
2533 if (sh->sh_type == SHT_SYMTAB) {
2534 if (symtab) {
2535 tcc_error_noabort("object must contain only one symtab");
2536 fail:
2537 ret = -1;
2538 goto the_end;
2539 }
2540 nb_syms = sh->sh_size / sizeof(ElfW(Sym));
2541 symtab = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
2542 sm_table[i].s = symtab_section;
2543
2544 /* now load strtab */
2545 sh = &shdr[sh->sh_link];
2546 strtab = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
2547 }
2548 }
2549
2550 /* now examine each section and try to merge its content with the
2551 ones in memory */
2552 for(i = 1; i < ehdr.e_shnum; i++) {
2553 /* no need to examine section name strtab */
2554 if (i == ehdr.e_shstrndx)
2555 continue;
2556 sh = &shdr[i];
2557 sh_name = (char *) strsec + sh->sh_name;
2558 /* ignore sections types we do not handle */
2559 if (sh->sh_type != SHT_PROGBITS &&
2560 sh->sh_type != SHT_RELX &&
2561 #ifdef TCC_ARM_EABI
2562 sh->sh_type != SHT_ARM_EXIDX &&
2563 #endif
2564 sh->sh_type != SHT_NOBITS &&
2565 sh->sh_type != SHT_PREINIT_ARRAY &&
2566 sh->sh_type != SHT_INIT_ARRAY &&
2567 sh->sh_type != SHT_FINI_ARRAY &&
2568 strcmp(sh_name, ".stabstr")
2569 )
2570 continue;
2571 if (sh->sh_addralign < 1)
2572 sh->sh_addralign = 1;
2573 /* find corresponding section, if any */
2574 for(j = 1; j < s1->nb_sections;j++) {
2575 s = s1->sections[j];
2576 if (!strcmp(s->name, sh_name)) {
2577 if (!strncmp(sh_name, ".gnu.linkonce",
2578 sizeof(".gnu.linkonce") - 1)) {
2579 /* if a 'linkonce' section is already present, we
2580 do not add it again. It is a little tricky as
2581 symbols can still be defined in
2582 it. */
2583 sm_table[i].link_once = 1;
2584 goto next;
2585 } else {
2586 goto found;
2587 }
2588 }
2589 }
2590 /* not found: create new section */
2591 s = new_section(s1, sh_name, sh->sh_type, sh->sh_flags);
2592 /* take as much info as possible from the section. sh_link and
2593 sh_info will be updated later */
2594 s->sh_addralign = sh->sh_addralign;
2595 s->sh_entsize = sh->sh_entsize;
2596 sm_table[i].new_section = 1;
2597 found:
2598 if (sh->sh_type != s->sh_type) {
2599 tcc_error_noabort("invalid section type");
2600 goto fail;
2601 }
2602
2603 /* align start of section */
2604 offset = s->data_offset;
2605
2606 if (0 == strcmp(sh_name, ".stab")) {
2607 stab_index = i;
2608 goto no_align;
2609 }
2610 if (0 == strcmp(sh_name, ".stabstr")) {
2611 stabstr_index = i;
2612 goto no_align;
2613 }
2614
2615 size = sh->sh_addralign - 1;
2616 offset = (offset + size) & ~size;
2617 if (sh->sh_addralign > s->sh_addralign)
2618 s->sh_addralign = sh->sh_addralign;
2619 s->data_offset = offset;
2620 no_align:
2621 sm_table[i].offset = offset;
2622 sm_table[i].s = s;
2623 /* concatenate sections */
2624 size = sh->sh_size;
2625 if (sh->sh_type != SHT_NOBITS) {
2626 unsigned char *ptr;
2627 lseek(fd, file_offset + sh->sh_offset, SEEK_SET);
2628 ptr = section_ptr_add(s, size);
2629 read(fd, ptr, size);
2630 } else {
2631 s->data_offset += size;
2632 }
2633 next: ;
2634 }
2635
2636 /* gr relocate stab strings */
2637 if (stab_index && stabstr_index) {
2638 Stab_Sym *a, *b;
2639 unsigned o;
2640 s = sm_table[stab_index].s;
2641 a = (Stab_Sym *)(s->data + sm_table[stab_index].offset);
2642 b = (Stab_Sym *)(s->data + s->data_offset);
2643 o = sm_table[stabstr_index].offset;
2644 while (a < b)
2645 a->n_strx += o, a++;
2646 }
2647
2648 /* second short pass to update sh_link and sh_info fields of new
2649 sections */
2650 for(i = 1; i < ehdr.e_shnum; i++) {
2651 s = sm_table[i].s;
2652 if (!s || !sm_table[i].new_section)
2653 continue;
2654 sh = &shdr[i];
2655 if (sh->sh_link > 0)
2656 s->link = sm_table[sh->sh_link].s;
2657 if (sh->sh_type == SHT_RELX) {
2658 s->sh_info = sm_table[sh->sh_info].s->sh_num;
2659 /* update backward link */
2660 s1->sections[s->sh_info]->reloc = s;
2661 }
2662 }
2663 sm = sm_table;
2664
2665 /* resolve symbols */
2666 old_to_new_syms = tcc_mallocz(nb_syms * sizeof(int));
2667
2668 sym = symtab + 1;
2669 for(i = 1; i < nb_syms; i++, sym++) {
2670 if (sym->st_shndx != SHN_UNDEF &&
2671 sym->st_shndx < SHN_LORESERVE) {
2672 sm = &sm_table[sym->st_shndx];
2673 if (sm->link_once) {
2674 /* if a symbol is in a link once section, we use the
2675 already defined symbol. It is very important to get
2676 correct relocations */
2677 if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
2678 name = (char *) strtab + sym->st_name;
2679 sym_index = find_elf_sym(symtab_section, name);
2680 if (sym_index)
2681 old_to_new_syms[i] = sym_index;
2682 }
2683 continue;
2684 }
2685 /* if no corresponding section added, no need to add symbol */
2686 if (!sm->s)
2687 continue;
2688 /* convert section number */
2689 sym->st_shndx = sm->s->sh_num;
2690 /* offset value */
2691 sym->st_value += sm->offset;
2692 }
2693 /* add symbol */
2694 name = (char *) strtab + sym->st_name;
2695 sym_index = add_elf_sym(symtab_section, sym->st_value, sym->st_size,
2696 sym->st_info, sym->st_other,
2697 sym->st_shndx, name);
2698 old_to_new_syms[i] = sym_index;
2699 }
2700
2701 /* third pass to patch relocation entries */
2702 for(i = 1; i < ehdr.e_shnum; i++) {
2703 s = sm_table[i].s;
2704 if (!s)
2705 continue;
2706 sh = &shdr[i];
2707 offset = sm_table[i].offset;
2708 switch(s->sh_type) {
2709 case SHT_RELX:
2710 /* take relocation offset information */
2711 offseti = sm_table[sh->sh_info].offset;
2712 for_each_elem(s, (offset / sizeof(*rel)), rel, ElfW_Rel) {
2713 int type;
2714 unsigned sym_index;
2715 /* convert symbol index */
2716 type = ELFW(R_TYPE)(rel->r_info);
2717 sym_index = ELFW(R_SYM)(rel->r_info);
2718 /* NOTE: only one symtab assumed */
2719 if (sym_index >= nb_syms)
2720 goto invalid_reloc;
2721 sym_index = old_to_new_syms[sym_index];
2722 /* ignore link_once in rel section. */
2723 if (!sym_index && !sm->link_once
2724 #ifdef TCC_TARGET_ARM
2725 && type != R_ARM_V4BX
2726 #endif
2727 ) {
2728 invalid_reloc:
2729 tcc_error_noabort("Invalid relocation entry [%2d] '%s' @ %.8x",
2730 i, strsec + sh->sh_name, rel->r_offset);
2731 goto fail;
2732 }
2733 rel->r_info = ELFW(R_INFO)(sym_index, type);
2734 /* offset the relocation offset */
2735 rel->r_offset += offseti;
2736 #ifdef TCC_TARGET_ARM
2737 /* Jumps and branches from a Thumb code to a PLT entry need
2738 special handling since PLT entries are ARM code.
2739 Unconditional bl instructions referencing PLT entries are
2740 handled by converting these instructions into blx
2741 instructions. Other case of instructions referencing a PLT
2742 entry require to add a Thumb stub before the PLT entry to
2743 switch to ARM mode. We set bit plt_thumb_stub of the
2744 attribute of a symbol to indicate such a case. */
2745 if (type == R_ARM_THM_JUMP24)
2746 alloc_sym_attr(s1, sym_index)->plt_thumb_stub = 1;
2747 #endif
2748 }
2749 break;
2750 default:
2751 break;
2752 }
2753 }
2754
2755 ret = 0;
2756 the_end:
2757 tcc_free(symtab);
2758 tcc_free(strtab);
2759 tcc_free(old_to_new_syms);
2760 tcc_free(sm_table);
2761 tcc_free(strsec);
2762 tcc_free(shdr);
2763 return ret;
2764 }
2765
2766 typedef struct ArchiveHeader {
2767 char ar_name[16]; /* name of this member */
2768 char ar_date[12]; /* file mtime */
2769 char ar_uid[6]; /* owner uid; printed as decimal */
2770 char ar_gid[6]; /* owner gid; printed as decimal */
2771 char ar_mode[8]; /* file mode, printed as octal */
2772 char ar_size[10]; /* file size, printed as decimal */
2773 char ar_fmag[2]; /* should contain ARFMAG */
2774 } ArchiveHeader;
2775
2776 static int get_be32(const uint8_t *b)
2777 {
2778 return b[3] | (b[2] << 8) | (b[1] << 16) | (b[0] << 24);
2779 }
2780
2781 /* load only the objects which resolve undefined symbols */
2782 static int tcc_load_alacarte(TCCState *s1, int fd, int size)
2783 {
2784 int i, bound, nsyms, sym_index, off, ret;
2785 uint8_t *data;
2786 const char *ar_names, *p;
2787 const uint8_t *ar_index;
2788 ElfW(Sym) *sym;
2789
2790 data = tcc_malloc(size);
2791 if (read(fd, data, size) != size)
2792 goto fail;
2793 nsyms = get_be32(data);
2794 ar_index = data + 4;
2795 ar_names = (char *) ar_index + nsyms * 4;
2796
2797 do {
2798 bound = 0;
2799 for(p = ar_names, i = 0; i < nsyms; i++, p += strlen(p)+1) {
2800 sym_index = find_elf_sym(symtab_section, p);
2801 if(sym_index) {
2802 sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
2803 if(sym->st_shndx == SHN_UNDEF) {
2804 off = get_be32(ar_index + i * 4) + sizeof(ArchiveHeader);
2805 ++bound;
2806 lseek(fd, off, SEEK_SET);
2807 if(tcc_load_object_file(s1, fd, off) < 0) {
2808 fail:
2809 ret = -1;
2810 goto the_end;
2811 }
2812 }
2813 }
2814 }
2815 } while(bound);
2816 ret = 0;
2817 the_end:
2818 tcc_free(data);
2819 return ret;
2820 }
2821
2822 /* load a '.a' file */
2823 ST_FUNC int tcc_load_archive(TCCState *s1, int fd)
2824 {
2825 ArchiveHeader hdr;
2826 char ar_size[11];
2827 char ar_name[17];
2828 char magic[8];
2829 int size, len, i;
2830 unsigned long file_offset;
2831
2832 /* skip magic which was already checked */
2833 read(fd, magic, sizeof(magic));
2834
2835 for(;;) {
2836 len = read(fd, &hdr, sizeof(hdr));
2837 if (len == 0)
2838 break;
2839 if (len != sizeof(hdr)) {
2840 tcc_error_noabort("invalid archive");
2841 return -1;
2842 }
2843 memcpy(ar_size, hdr.ar_size, sizeof(hdr.ar_size));
2844 ar_size[sizeof(hdr.ar_size)] = '\0';
2845 size = strtol(ar_size, NULL, 0);
2846 memcpy(ar_name, hdr.ar_name, sizeof(hdr.ar_name));
2847 for(i = sizeof(hdr.ar_name) - 1; i >= 0; i--) {
2848 if (ar_name[i] != ' ')
2849 break;
2850 }
2851 ar_name[i + 1] = '\0';
2852 file_offset = lseek(fd, 0, SEEK_CUR);
2853 /* align to even */
2854 size = (size + 1) & ~1;
2855 if (!strcmp(ar_name, "/")) {
2856 /* coff symbol table : we handle it */
2857 if(s1->alacarte_link)
2858 return tcc_load_alacarte(s1, fd, size);
2859 } else if (!strcmp(ar_name, "//") ||
2860 !strcmp(ar_name, "__.SYMDEF") ||
2861 !strcmp(ar_name, "__.SYMDEF/") ||
2862 !strcmp(ar_name, "ARFILENAMES/")) {
2863 /* skip symbol table or archive names */
2864 } else {
2865 if (tcc_load_object_file(s1, fd, file_offset) < 0)
2866 return -1;
2867 }
2868 lseek(fd, file_offset + size, SEEK_SET);
2869 }
2870 return 0;
2871 }
2872
2873 #ifndef TCC_TARGET_PE
2874 /* load a DLL and all referenced DLLs. 'level = 0' means that the DLL
2875 is referenced by the user (so it should be added as DT_NEEDED in
2876 the generated ELF file) */
2877 ST_FUNC int tcc_load_dll(TCCState *s1, int fd, const char *filename, int level)
2878 {
2879 ElfW(Ehdr) ehdr;
2880 ElfW(Shdr) *shdr, *sh, *sh1;
2881 int i, j, nb_syms, nb_dts, sym_bind, ret;
2882 ElfW(Sym) *sym, *dynsym;
2883 ElfW(Dyn) *dt, *dynamic;
2884 unsigned char *dynstr;
2885 const char *name, *soname;
2886 DLLReference *dllref;
2887
2888 read(fd, &ehdr, sizeof(ehdr));
2889
2890 /* test CPU specific stuff */
2891 if (ehdr.e_ident[5] != ELFDATA2LSB ||
2892 ehdr.e_machine != EM_TCC_TARGET) {
2893 tcc_error_noabort("bad architecture");
2894 return -1;
2895 }
2896
2897 /* read sections */
2898 shdr = load_data(fd, ehdr.e_shoff, sizeof(ElfW(Shdr)) * ehdr.e_shnum);
2899
2900 /* load dynamic section and dynamic symbols */
2901 nb_syms = 0;
2902 nb_dts = 0;
2903 dynamic = NULL;
2904 dynsym = NULL; /* avoid warning */
2905 dynstr = NULL; /* avoid warning */
2906 for(i = 0, sh = shdr; i < ehdr.e_shnum; i++, sh++) {
2907 switch(sh->sh_type) {
2908 case SHT_DYNAMIC:
2909 nb_dts = sh->sh_size / sizeof(ElfW(Dyn));
2910 dynamic = load_data(fd, sh->sh_offset, sh->sh_size);
2911 break;
2912 case SHT_DYNSYM:
2913 nb_syms = sh->sh_size / sizeof(ElfW(Sym));
2914 dynsym = load_data(fd, sh->sh_offset, sh->sh_size);
2915 sh1 = &shdr[sh->sh_link];
2916 dynstr = load_data(fd, sh1->sh_offset, sh1->sh_size);
2917 break;
2918 default:
2919 break;
2920 }
2921 }
2922
2923 /* compute the real library name */
2924 soname = tcc_basename(filename);
2925
2926 for(i = 0, dt = dynamic; i < nb_dts; i++, dt++) {
2927 if (dt->d_tag == DT_SONAME) {
2928 soname = (char *) dynstr + dt->d_un.d_val;
2929 }
2930 }
2931
2932 /* if the dll is already loaded, do not load it */
2933 for(i = 0; i < s1->nb_loaded_dlls; i++) {
2934 dllref = s1->loaded_dlls[i];
2935 if (!strcmp(soname, dllref->name)) {
2936 /* but update level if needed */
2937 if (level < dllref->level)
2938 dllref->level = level;
2939 ret = 0;
2940 goto the_end;
2941 }
2942 }
2943
2944 /* add the dll and its level */
2945 dllref = tcc_mallocz(sizeof(DLLReference) + strlen(soname));
2946 dllref->level = level;
2947 strcpy(dllref->name, soname);
2948 dynarray_add((void ***)&s1->loaded_dlls, &s1->nb_loaded_dlls, dllref);
2949
2950 /* add dynamic symbols in dynsym_section */
2951 for(i = 1, sym = dynsym + 1; i < nb_syms; i++, sym++) {
2952 sym_bind = ELFW(ST_BIND)(sym->st_info);
2953 if (sym_bind == STB_LOCAL)
2954 continue;
2955 name = (char *) dynstr + sym->st_name;
2956 add_elf_sym(s1->dynsymtab_section, sym->st_value, sym->st_size,
2957 sym->st_info, sym->st_other, sym->st_shndx, name);
2958 }
2959
2960 /* load all referenced DLLs */
2961 for(i = 0, dt = dynamic; i < nb_dts; i++, dt++) {
2962 switch(dt->d_tag) {
2963 case DT_NEEDED:
2964 name = (char *) dynstr + dt->d_un.d_val;
2965 for(j = 0; j < s1->nb_loaded_dlls; j++) {
2966 dllref = s1->loaded_dlls[j];
2967 if (!strcmp(name, dllref->name))
2968 goto already_loaded;
2969 }
2970 if (tcc_add_dll(s1, name, AFF_REFERENCED_DLL) < 0) {
2971 tcc_error_noabort("referenced dll '%s' not found", name);
2972 ret = -1;
2973 goto the_end;
2974 }
2975 already_loaded:
2976 break;
2977 }
2978 }
2979 ret = 0;
2980 the_end:
2981 tcc_free(dynstr);
2982 tcc_free(dynsym);
2983 tcc_free(dynamic);
2984 tcc_free(shdr);
2985 return ret;
2986 }
2987
2988 #define LD_TOK_NAME 256
2989 #define LD_TOK_EOF (-1)
2990
2991 /* return next ld script token */
2992 static int ld_next(TCCState *s1, char *name, int name_size)
2993 {
2994 int c;
2995 char *q;
2996
2997 redo:
2998 switch(ch) {
2999 case ' ':
3000 case '\t':
3001 case '\f':
3002 case '\v':
3003 case '\r':
3004 case '\n':
3005 inp();
3006 goto redo;
3007 case '/':
3008 minp();
3009 if (ch == '*') {
3010 file->buf_ptr = parse_comment(file->buf_ptr);
3011 ch = file->buf_ptr[0];
3012 goto redo;
3013 } else {
3014 q = name;
3015 *q++ = '/';
3016 goto parse_name;
3017 }
3018 break;
3019 /* case 'a' ... 'z': */
3020 case 'a':
3021 case 'b':
3022 case 'c':
3023 case 'd':
3024 case 'e':
3025 case 'f':
3026 case 'g':
3027 case 'h':
3028 case 'i':
3029 case 'j':
3030 case 'k':
3031 case 'l':
3032 case 'm':
3033 case 'n':
3034 case 'o':
3035 case 'p':
3036 case 'q':
3037 case 'r':
3038 case 's':
3039 case 't':
3040 case 'u':
3041 case 'v':
3042 case 'w':
3043 case 'x':
3044 case 'y':
3045 case 'z':
3046 /* case 'A' ... 'z': */
3047 case 'A':
3048 case 'B':
3049 case 'C':
3050 case 'D':
3051 case 'E':
3052 case 'F':
3053 case 'G':
3054 case 'H':
3055 case 'I':
3056 case 'J':
3057 case 'K':
3058 case 'L':
3059 case 'M':
3060 case 'N':
3061 case 'O':
3062 case 'P':
3063 case 'Q':
3064 case 'R':
3065 case 'S':
3066 case 'T':
3067 case 'U':
3068 case 'V':
3069 case 'W':
3070 case 'X':
3071 case 'Y':
3072 case 'Z':
3073 case '_':
3074 case '\\':
3075 case '.':
3076 case '$':
3077 case '~':
3078 q = name;
3079 parse_name:
3080 for(;;) {
3081 if (!((ch >= 'a' && ch <= 'z') ||
3082 (ch >= 'A' && ch <= 'Z') ||
3083 (ch >= '0' && ch <= '9') ||
3084 strchr("/.-_+=$:\\,~", ch)))
3085 break;
3086 if ((q - name) < name_size - 1) {
3087 *q++ = ch;
3088 }
3089 minp();
3090 }
3091 *q = '\0';
3092 c = LD_TOK_NAME;
3093 break;
3094 case CH_EOF:
3095 c = LD_TOK_EOF;
3096 break;
3097 default:
3098 c = ch;
3099 inp();
3100 break;
3101 }
3102 return c;
3103 }
3104
3105 static int ld_add_file(TCCState *s1, const char filename[])
3106 {
3107 int ret;
3108
3109 ret = tcc_add_file_internal(s1, filename, 0);
3110 if (ret)
3111 ret = tcc_add_dll(s1, filename, 0);
3112 return ret;
3113 }
3114
3115 static inline int new_undef_syms(void)
3116 {
3117 int ret = 0;
3118 ret = new_undef_sym;
3119 new_undef_sym = 0;
3120 return ret;
3121 }
3122
3123 static int ld_add_file_list(TCCState *s1, const char *cmd, int as_needed)
3124 {
3125 char filename[1024], libname[1024];
3126 int t, group, nblibs = 0, ret = 0;
3127 char **libs = NULL;
3128
3129 group = !strcmp(cmd, "GROUP");
3130 if (!as_needed)
3131 new_undef_syms();
3132 t = ld_next(s1, filename, sizeof(filename));
3133 if (t != '(')
3134 expect("(");
3135 t = ld_next(s1, filename, sizeof(filename));
3136 for(;;) {
3137 libname[0] = '\0';
3138 if (t == LD_TOK_EOF) {
3139 tcc_error_noabort("unexpected end of file");
3140 ret = -1;
3141 goto lib_parse_error;
3142 } else if (t == ')') {
3143 break;
3144 } else if (t == '-') {
3145 t = ld_next(s1, filename, sizeof(filename));
3146 if ((t != LD_TOK_NAME) || (filename[0] != 'l')) {
3147 tcc_error_noabort("library name expected");
3148 ret = -1;
3149 goto lib_parse_error;
3150 }
3151 pstrcpy(libname, sizeof libname, &filename[1]);
3152 if (s1->static_link) {
3153 snprintf(filename, sizeof filename, "lib%s.a", libname);
3154 } else {
3155 snprintf(filename, sizeof filename, "lib%s.so", libname);
3156 }
3157 } else if (t != LD_TOK_NAME) {
3158 tcc_error_noabort("filename expected");
3159 ret = -1;
3160 goto lib_parse_error;
3161 }
3162 if (!strcmp(filename, "AS_NEEDED")) {
3163 ret = ld_add_file_list(s1, cmd, 1);
3164 if (ret)
3165 goto lib_parse_error;
3166 } else {
3167 /* TODO: Implement AS_NEEDED support. Ignore it for now */
3168 if (!as_needed) {
3169 ret = ld_add_file(s1, filename);
3170 if (ret)
3171 goto lib_parse_error;
3172 if (group) {
3173 /* Add the filename *and* the libname to avoid future conversions */
3174 dynarray_add((void ***) &libs, &nblibs, tcc_strdup(filename));
3175 if (libname[0] != '\0')
3176 dynarray_add((void ***) &libs, &nblibs, tcc_strdup(libname));
3177 }
3178 }
3179 }
3180 t = ld_next(s1, filename, sizeof(filename));
3181 if (t == ',') {
3182 t = ld_next(s1, filename, sizeof(filename));
3183 }
3184 }
3185 if (group && !as_needed) {
3186 while (new_undef_syms()) {
3187 int i;
3188
3189 for (i = 0; i < nblibs; i ++)
3190 ld_add_file(s1, libs[i]);
3191 }
3192 }
3193 lib_parse_error:
3194 dynarray_reset(&libs, &nblibs);
3195 return ret;
3196 }
3197
3198 /* interpret a subset of GNU ldscripts to handle the dummy libc.so
3199 files */
3200 ST_FUNC int tcc_load_ldscript(TCCState *s1)
3201 {
3202 char cmd[64];
3203 char filename[1024];
3204 int t, ret;
3205
3206 ch = file->buf_ptr[0];
3207 ch = handle_eob();
3208 for(;;) {
3209 t = ld_next(s1, cmd, sizeof(cmd));
3210 if (t == LD_TOK_EOF)
3211 return 0;
3212 else if (t != LD_TOK_NAME)
3213 return -1;
3214 if (!strcmp(cmd, "INPUT") ||
3215 !strcmp(cmd, "GROUP")) {
3216 ret = ld_add_file_list(s1, cmd, 0);
3217 if (ret)
3218 return ret;
3219 } else if (!strcmp(cmd, "OUTPUT_FORMAT") ||
3220 !strcmp(cmd, "TARGET")) {
3221 /* ignore some commands */
3222 t = ld_next(s1, cmd, sizeof(cmd));
3223 if (t != '(')
3224 expect("(");
3225 for(;;) {
3226 t = ld_next(s1, filename, sizeof(filename));
3227 if (t == LD_TOK_EOF) {
3228 tcc_error_noabort("unexpected end of file");
3229 return -1;
3230 } else if (t == ')') {
3231 break;
3232 }
3233 }
3234 } else {
3235 return -1;
3236 }
3237 }
3238 return 0;
3239 }
3240 #endif /* !TCC_TARGET_PE */
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