forked from TinyCC/tinycc
-
Notifications
You must be signed in to change notification settings - Fork 0
/
tccmacho.c
1057 lines (965 loc) · 38 KB
/
tccmacho.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* Mach-O file handling for TCC
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "tcc.h"
/* In order to make life easy for us we are generating Mach-O files which
don't make use of some modern features, but which aren't entirely classic
either in that they do use some modern features. We're also only
generating 64bit Mach-O files, and only native endian at that.
In particular we're generating executables that don't make use of
DYLD_INFO for dynamic linking info, as that requires us building a
trie of exported names. We're simply using classic symbol tables which
are still supported by modern dyld.
But we do use LC_MAIN, which is a "modern" feature in order to not have
to setup our own crt code. We're not using lazy linking, so even function
calls are resolved at startup. */
#define DEBUG_MACHO 0
#define dprintf if (DEBUG_MACHO) printf
struct fat_header {
uint32_t magic; /* FAT_MAGIC or FAT_MAGIC_64 */
uint32_t nfat_arch; /* number of structs that follow */
};
struct fat_arch {
int cputype; /* cpu specifier (int) */
int cpusubtype; /* machine specifier (int) */
uint32_t offset; /* file offset to this object file */
uint32_t size; /* size of this object file */
uint32_t align; /* alignment as a power of 2 */
};
#define FAT_MAGIC 0xcafebabe
#define FAT_CIGAM 0xbebafeca
#define FAT_MAGIC_64 0xcafebabf
#define FAT_CIGAM_64 0xbfbafeca
struct mach_header {
uint32_t magic; /* mach magic number identifier */
int cputype; /* cpu specifier */
int cpusubtype; /* machine specifier */
uint32_t filetype; /* type of file */
uint32_t ncmds; /* number of load commands */
uint32_t sizeofcmds; /* the size of all the load commands */
uint32_t flags; /* flags */
};
struct mach_header_64 {
struct mach_header mh;
uint32_t reserved; /* reserved, pad to 64bit */
};
/* Constant for the magic field of the mach_header (32-bit architectures) */
#define MH_MAGIC 0xfeedface /* the mach magic number */
#define MH_CIGAM 0xcefaedfe /* NXSwapInt(MH_MAGIC) */
#define MH_MAGIC_64 0xfeedfacf /* the 64-bit mach magic number */
#define MH_CIGAM_64 0xcffaedfe /* NXSwapInt(MH_MAGIC_64) */
struct load_command {
uint32_t cmd; /* type of load command */
uint32_t cmdsize; /* total size of command in bytes */
};
#define LC_REQ_DYLD 0x80000000
#define LC_SYMTAB 0x2
#define LC_DYSYMTAB 0xb
#define LC_LOAD_DYLIB 0xc
#define LC_ID_DYLIB 0xd
#define LC_LOAD_DYLINKER 0xe
#define LC_SEGMENT_64 0x19
#define LC_REEXPORT_DYLIB (0x1f | LC_REQ_DYLD)
#define LC_MAIN (0x28|LC_REQ_DYLD)
typedef int vm_prot_t;
struct segment_command_64 { /* for 64-bit architectures */
uint32_t cmd; /* LC_SEGMENT_64 */
uint32_t cmdsize; /* includes sizeof section_64 structs */
char segname[16]; /* segment name */
uint64_t vmaddr; /* memory address of this segment */
uint64_t vmsize; /* memory size of this segment */
uint64_t fileoff; /* file offset of this segment */
uint64_t filesize; /* amount to map from the file */
vm_prot_t maxprot; /* maximum VM protection */
vm_prot_t initprot; /* initial VM protection */
uint32_t nsects; /* number of sections in segment */
uint32_t flags; /* flags */
};
struct section_64 { /* for 64-bit architectures */
char sectname[16]; /* name of this section */
char segname[16]; /* segment this section goes in */
uint64_t addr; /* memory address of this section */
uint64_t size; /* size in bytes of this section */
uint32_t offset; /* file offset of this section */
uint32_t align; /* section alignment (power of 2) */
uint32_t reloff; /* file offset of relocation entries */
uint32_t nreloc; /* number of relocation entries */
uint32_t flags; /* flags (section type and attributes)*/
uint32_t reserved1; /* reserved (for offset or index) */
uint32_t reserved2; /* reserved (for count or sizeof) */
uint32_t reserved3; /* reserved */
};
#define S_REGULAR 0x0
#define S_ZEROFILL 0x1
#define S_NON_LAZY_SYMBOL_POINTERS 0x6
#define S_MOD_INIT_FUNC_POINTERS 0x9
#define S_MOD_TERM_FUNC_POINTERS 0xa
#define S_ATTR_PURE_INSTRUCTIONS 0x80000000
#define S_ATTR_SOME_INSTRUCTIONS 0x00000400
typedef uint32_t lc_str;
struct dylib_command {
uint32_t cmd; /* LC_ID_DYLIB, LC_LOAD_{,WEAK_}DYLIB,
LC_REEXPORT_DYLIB */
uint32_t cmdsize; /* includes pathname string */
lc_str name; /* library's path name */
uint32_t timestamp; /* library's build time stamp */
uint32_t current_version; /* library's current version number */
uint32_t compatibility_version; /* library's compatibility vers number*/
};
struct dylinker_command {
uint32_t cmd; /* LC_ID_DYLINKER, LC_LOAD_DYLINKER or
LC_DYLD_ENVIRONMENT */
uint32_t cmdsize; /* includes pathname string */
lc_str name; /* dynamic linker's path name */
};
struct symtab_command {
uint32_t cmd; /* LC_SYMTAB */
uint32_t cmdsize; /* sizeof(struct symtab_command) */
uint32_t symoff; /* symbol table offset */
uint32_t nsyms; /* number of symbol table entries */
uint32_t stroff; /* string table offset */
uint32_t strsize; /* string table size in bytes */
};
struct dysymtab_command {
uint32_t cmd; /* LC_DYSYMTAB */
uint32_t cmdsize; /* sizeof(struct dysymtab_command) */
uint32_t ilocalsym; /* index to local symbols */
uint32_t nlocalsym; /* number of local symbols */
uint32_t iextdefsym;/* index to externally defined symbols */
uint32_t nextdefsym;/* number of externally defined symbols */
uint32_t iundefsym; /* index to undefined symbols */
uint32_t nundefsym; /* number of undefined symbols */
uint32_t tocoff; /* file offset to table of contents */
uint32_t ntoc; /* number of entries in table of contents */
uint32_t modtaboff; /* file offset to module table */
uint32_t nmodtab; /* number of module table entries */
uint32_t extrefsymoff; /* offset to referenced symbol table */
uint32_t nextrefsyms; /* number of referenced symbol table entries */
uint32_t indirectsymoff;/* file offset to the indirect symbol table */
uint32_t nindirectsyms; /* number of indirect symbol table entries */
uint32_t extreloff; /* offset to external relocation entries */
uint32_t nextrel; /* number of external relocation entries */
uint32_t locreloff; /* offset to local relocation entries */
uint32_t nlocrel; /* number of local relocation entries */
};
#define INDIRECT_SYMBOL_LOCAL 0x80000000
struct entry_point_command {
uint32_t cmd; /* LC_MAIN only used in MH_EXECUTE filetypes */
uint32_t cmdsize; /* 24 */
uint64_t entryoff; /* file (__TEXT) offset of main() */
uint64_t stacksize;/* if not zero, initial stack size */
};
enum skind {
sk_unknown = 0,
sk_discard,
sk_text,
sk_stubs,
sk_ro_data,
sk_uw_info,
sk_nl_ptr, // non-lazy pointers, aka GOT
sk_la_ptr, // lazy pointers
sk_init,
sk_fini,
sk_rw_data,
sk_bss,
sk_linkedit,
sk_last
};
struct nlist_64 {
uint32_t n_strx; /* index into the string table */
uint8_t n_type; /* type flag, see below */
uint8_t n_sect; /* section number or NO_SECT */
uint16_t n_desc; /* see <mach-o/stab.h> */
uint64_t n_value; /* value of this symbol (or stab offset) */
};
#define N_UNDF 0x0
#define N_ABS 0x2
#define N_EXT 0x1
#define N_SECT 0xe
#define N_WEAK_REF 0x0040
#define N_WEAK_DEF 0x0080
struct macho {
struct mach_header_64 mh;
int seg2lc[4], nseg;
struct load_command **lc;
struct entry_point_command *ep;
int nlc;
struct {
Section *s;
int machosect;
} sk_to_sect[sk_last];
int *elfsectomacho;
int *e2msym;
Section *symtab, *strtab, *wdata, *indirsyms, *stubs;
int stubsym;
uint32_t ilocal, iextdef, iundef;
};
#define SHT_LINKEDIT (SHT_LOOS + 42)
#define SHN_FROMDLL (SHN_LOOS + 2) /* Symbol is undefined, comes from a DLL */
static void * add_lc(struct macho *mo, uint32_t cmd, uint32_t cmdsize)
{
struct load_command *lc = tcc_mallocz(cmdsize);
lc->cmd = cmd;
lc->cmdsize = cmdsize;
mo->lc = tcc_realloc(mo->lc, sizeof(mo->lc[0]) * (mo->nlc + 1));
mo->lc[mo->nlc++] = lc;
return lc;
}
static struct segment_command_64 * add_segment(struct macho *mo, const char *name)
{
struct segment_command_64 *sc = add_lc(mo, LC_SEGMENT_64, sizeof(*sc));
strncpy(sc->segname, name, 16);
mo->seg2lc[mo->nseg++] = mo->nlc - 1;
return sc;
}
static struct segment_command_64 * get_segment(struct macho *mo, int i)
{
return (struct segment_command_64 *) (mo->lc[mo->seg2lc[i]]);
}
static int add_section(struct macho *mo, struct segment_command_64 **_seg, const char *name)
{
struct segment_command_64 *seg = *_seg;
int ret = seg->nsects;
struct section_64 *sec;
seg->nsects++;
seg->cmdsize += sizeof(*sec);
seg = tcc_realloc(seg, sizeof(*seg) + seg->nsects * sizeof(*sec));
sec = (struct section_64*)((char*)seg + sizeof(*seg)) + ret;
memset(sec, 0, sizeof(*sec));
strncpy(sec->sectname, name, 16);
strncpy(sec->segname, seg->segname, 16);
*_seg = seg;
return ret;
}
static struct section_64 *get_section(struct segment_command_64 *seg, int i)
{
return (struct section_64*)((char*)seg + sizeof(*seg)) + i;
}
static void * add_dylib(struct macho *mo, char *name)
{
struct dylib_command *lc;
int sz = (sizeof(*lc) + strlen(name) + 1 + 7) & -8;
lc = add_lc(mo, LC_LOAD_DYLIB, sz);
lc->name = sizeof(*lc);
strcpy((char*)lc + lc->name, name);
lc->timestamp = 2;
lc->current_version = 1 << 16;
lc->compatibility_version = 1 << 16;
return lc;
}
static void check_relocs(TCCState *s1, struct macho *mo)
{
Section *s;
ElfW_Rel *rel;
ElfW(Sym) *sym;
int i, type, gotplt_entry, sym_index, for_code;
struct sym_attr *attr;
s1->got = new_section(s1, ".got", SHT_PROGBITS, SHF_ALLOC | SHF_WRITE);
mo->indirsyms = new_section(s1, "LEINDIR", SHT_LINKEDIT, SHF_ALLOC | SHF_WRITE);
for (i = 1; i < s1->nb_sections; i++) {
s = s1->sections[i];
if (s->sh_type != SHT_RELX)
continue;
for_each_elem(s, 0, rel, ElfW_Rel) {
type = ELFW(R_TYPE)(rel->r_info);
gotplt_entry = gotplt_entry_type(type);
for_code = code_reloc(type);
/* We generate a non-lazy pointer for used undefined symbols
and for defined symbols that must have a place for their
address due to codegen (i.e. a reloc requiring a got slot). */
sym_index = ELFW(R_SYM)(rel->r_info);
sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
if (sym->st_shndx == SHN_UNDEF
|| gotplt_entry == ALWAYS_GOTPLT_ENTRY) {
attr = get_sym_attr(s1, sym_index, 1);
if (!attr->dyn_index) {
uint32_t *pi = section_ptr_add(mo->indirsyms, sizeof(*pi));
attr->got_offset = s1->got->data_offset;
attr->plt_offset = -1;
attr->dyn_index = 1; /* used as flag */
section_ptr_add(s1->got, PTR_SIZE);
if (ELFW(ST_BIND)(sym->st_info) == STB_LOCAL) {
if (sym->st_shndx == SHN_UNDEF)
tcc_error("undefined local symbol???");
*pi = INDIRECT_SYMBOL_LOCAL;
/* The pointer slot we generated must point to the
symbol, whose address is only known after layout,
so register a simple relocation for that. */
put_elf_reloc(s1->symtab, s1->got, attr->got_offset,
R_DATA_PTR, sym_index);
} else
*pi = mo->e2msym[sym_index];
}
if (for_code) {
if (attr->plt_offset == -1) {
uint8_t *jmp;
attr->plt_offset = mo->stubs->data_offset;
jmp = section_ptr_add(mo->stubs, 6);
jmp[0] = 0xff; /* jmpq *ofs(%rip) */
jmp[1] = 0x25;
put_elf_reloc(s1->symtab, mo->stubs,
attr->plt_offset + 2,
R_X86_64_GOTPCREL, sym_index);
}
rel->r_info = ELFW(R_INFO)(mo->stubsym, type);
rel->r_addend += attr->plt_offset;
}
}
}
}
}
static int check_symbols(TCCState *s1, struct macho *mo)
{
int sym_index, sym_end;
int ret = 0;
mo->ilocal = mo->iextdef = mo->iundef = -1;
sym_end = symtab_section->data_offset / sizeof(ElfW(Sym));
for (sym_index = 1; sym_index < sym_end; ++sym_index) {
int elf_index = ((struct nlist_64 *)mo->symtab->data + sym_index - 1)->n_value;
ElfW(Sym) *sym = (ElfW(Sym) *)symtab_section->data + elf_index;
const char *name = (char*)symtab_section->link->data + sym->st_name;
unsigned type = ELFW(ST_TYPE)(sym->st_info);
unsigned bind = ELFW(ST_BIND)(sym->st_info);
unsigned vis = ELFW(ST_VISIBILITY)(sym->st_other);
dprintf("%4d (%4d): %09lx %4d %4d %4d %3d %s\n",
sym_index, elf_index, (long)sym->st_value,
type, bind, vis, sym->st_shndx, name);
if (bind == STB_LOCAL) {
if (mo->ilocal == -1)
mo->ilocal = sym_index - 1;
if (mo->iextdef != -1 || mo->iundef != -1)
tcc_error("local syms after global ones");
} else if (sym->st_shndx != SHN_UNDEF) {
if (mo->iextdef == -1)
mo->iextdef = sym_index - 1;
if (mo->iundef != -1)
tcc_error("external defined symbol after undefined");
} else if (sym->st_shndx == SHN_UNDEF) {
if (mo->iundef == -1)
mo->iundef = sym_index - 1;
if (ELFW(ST_BIND)(sym->st_info) == STB_WEAK
|| find_elf_sym(s1->dynsymtab_section, name)) {
/* Mark the symbol as coming from a dylib so that
relocate_syms doesn't complain. Normally bind_exe_dynsyms
would do this check, and place the symbol into dynsym
which is checked by relocate_syms. But Mach-O doesn't use
bind_exe_dynsyms. */
sym->st_shndx = SHN_FROMDLL;
continue;
}
tcc_error_noabort("undefined symbol '%s'", name);
ret = -1;
}
}
return ret;
}
static void convert_symbol(TCCState *s1, struct macho *mo, struct nlist_64 *pn)
{
struct nlist_64 n = *pn;
ElfSym *sym = (ElfW(Sym) *)symtab_section->data + pn->n_value;
const char *name = (char*)symtab_section->link->data + sym->st_name;
switch(ELFW(ST_TYPE)(sym->st_info)) {
case STT_NOTYPE:
case STT_OBJECT:
case STT_FUNC:
case STT_SECTION:
n.n_type = N_SECT;
break;
case STT_FILE:
n.n_type = N_ABS;
break;
default:
tcc_error("unhandled ELF symbol type %d %s",
ELFW(ST_TYPE)(sym->st_info), name);
}
if (sym->st_shndx == SHN_UNDEF)
tcc_error("should have been rewritten to SHN_FROMDLL: %s", name);
else if (sym->st_shndx == SHN_FROMDLL)
n.n_type = N_UNDF, n.n_sect = 0;
else if (sym->st_shndx == SHN_ABS)
n.n_type = N_ABS, n.n_sect = 0;
else if (sym->st_shndx >= SHN_LORESERVE)
tcc_error("unhandled ELF symbol section %d %s", sym->st_shndx, name);
else if (!mo->elfsectomacho[sym->st_shndx])
tcc_error("ELF section %d not mapped into Mach-O for symbol %s",
sym->st_shndx, name);
else
n.n_sect = mo->elfsectomacho[sym->st_shndx];
if (ELFW(ST_BIND)(sym->st_info) == STB_GLOBAL)
n.n_type |= N_EXT;
else if (ELFW(ST_BIND)(sym->st_info) == STB_WEAK)
n.n_desc |= N_WEAK_REF | (n.n_type != N_UNDF ? N_WEAK_DEF : 0);
n.n_strx = pn->n_strx;
n.n_value = sym->st_value;
*pn = n;
}
static void convert_symbols(TCCState *s1, struct macho *mo)
{
struct nlist_64 *pn;
for_each_elem(mo->symtab, 0, pn, struct nlist_64)
convert_symbol(s1, mo, pn);
}
static int machosymcmp(const void *_a, const void *_b)
{
TCCState *s1 = tcc_state;
int ea = ((struct nlist_64 *)_a)->n_value;
int eb = ((struct nlist_64 *)_b)->n_value;
ElfSym *sa = (ElfSym *)symtab_section->data + ea;
ElfSym *sb = (ElfSym *)symtab_section->data + eb;
int r;
/* locals, then defined externals, then undefined externals, the
last two sections also by name, otherwise stable sort */
r = (ELFW(ST_BIND)(sb->st_info) == STB_LOCAL)
- (ELFW(ST_BIND)(sa->st_info) == STB_LOCAL);
if (r)
return r;
r = (sa->st_shndx == SHN_UNDEF) - (sb->st_shndx == SHN_UNDEF);
if (r)
return r;
if (ELFW(ST_BIND)(sa->st_info) != STB_LOCAL) {
const char * na = (char*)symtab_section->link->data + sa->st_name;
const char * nb = (char*)symtab_section->link->data + sb->st_name;
r = strcmp(na, nb);
if (r)
return r;
}
return ea - eb;
}
static void create_symtab(TCCState *s1, struct macho *mo)
{
int sym_index, sym_end;
struct nlist_64 *pn;
/* Stub creation belongs to check_relocs, but we need to create
the symbol now, so its included in the sorting. */
mo->stubs = new_section(s1, "__stubs", SHT_PROGBITS, SHF_ALLOC | SHF_EXECINSTR);
mo->stubsym = put_elf_sym(s1->symtab, 0, 0,
ELFW(ST_INFO)(STB_LOCAL, STT_SECTION), 0,
mo->stubs->sh_num, ".__stubs");
mo->symtab = new_section(s1, "LESYMTAB", SHT_LINKEDIT, SHF_ALLOC | SHF_WRITE);
mo->strtab = new_section(s1, "LESTRTAB", SHT_LINKEDIT, SHF_ALLOC | SHF_WRITE);
put_elf_str(mo->strtab, " "); /* Mach-O starts strtab with a space */
sym_end = symtab_section->data_offset / sizeof(ElfW(Sym));
pn = section_ptr_add(mo->symtab, sizeof(*pn) * (sym_end - 1));
for (sym_index = 1; sym_index < sym_end; ++sym_index) {
ElfW(Sym) *sym = (ElfW(Sym) *)symtab_section->data + sym_index;
const char *name = (char*)symtab_section->link->data + sym->st_name;
pn[sym_index - 1].n_strx = put_elf_str(mo->strtab, name);
pn[sym_index - 1].n_value = sym_index;
}
tcc_enter_state(s1); /* qsort needs global state */
qsort(pn, sym_end - 1, sizeof(*pn), machosymcmp);
tcc_exit_state(s1);
mo->e2msym = tcc_malloc(sym_end * sizeof(*mo->e2msym));
mo->e2msym[0] = -1;
for (sym_index = 1; sym_index < sym_end; ++sym_index) {
mo->e2msym[pn[sym_index - 1].n_value] = sym_index - 1;
}
}
const struct {
int seg;
uint32_t flags;
const char *name;
} skinfo[sk_last] = {
/*[sk_unknown] =*/ { 0 },
/*[sk_discard] =*/ { 0 },
/*[sk_text] =*/ { 1, S_REGULAR | S_ATTR_PURE_INSTRUCTIONS
| S_ATTR_SOME_INSTRUCTIONS, "__text" },
/*[sk_stubs] =*/ { 0 },
/*[sk_ro_data] =*/ { 1, S_REGULAR, "__rodata" },
/*[sk_uw_info] =*/ { 0 },
/*[sk_nl_ptr] =*/ { 2, S_NON_LAZY_SYMBOL_POINTERS, "__got" },
/*[sk_la_ptr] =*/ { 0 },
/*[sk_init] =*/ { 2, S_MOD_INIT_FUNC_POINTERS, "__mod_init_func" },
/*[sk_fini] =*/ { 2, S_MOD_TERM_FUNC_POINTERS, "__mod_term_func" },
/*[sk_rw_data] =*/ { 2, S_REGULAR, "__data" },
/*[sk_bss] =*/ { 2, S_ZEROFILL, "__bss" },
/*[sk_linkedit] =*/ { 3, S_REGULAR, NULL },
};
static void collect_sections(TCCState *s1, struct macho *mo)
{
int i, sk, numsec;
uint64_t curaddr, fileofs;
Section *s;
struct segment_command_64 *seg = NULL;
struct dylinker_command *dyldlc;
struct symtab_command *symlc;
struct dysymtab_command *dysymlc;
char *str;
seg = add_segment(mo, "__PAGEZERO");
seg->vmsize = (uint64_t)1 << 32;
seg = add_segment(mo, "__TEXT");
seg->vmaddr = (uint64_t)1 << 32;
seg->maxprot = 7; // rwx
seg->initprot = 5; // r-x
seg = add_segment(mo, "__DATA");
seg->vmaddr = -1;
seg->maxprot = 7; // rwx
seg->initprot = 3; // rw-
seg = add_segment(mo, "__LINKEDIT");
seg->vmaddr = -1;
seg->maxprot = 7; // rwx
seg->initprot = 1; // r--
mo->ep = add_lc(mo, LC_MAIN, sizeof(*mo->ep));
mo->ep->entryoff = 4096;
i = (sizeof(*dyldlc) + strlen("/usr/lib/dyld") + 1 + 7) &-8;
dyldlc = add_lc(mo, LC_LOAD_DYLINKER, i);
dyldlc->name = sizeof(*dyldlc);
str = (char*)dyldlc + dyldlc->name;
strcpy(str, "/usr/lib/dyld");
symlc = add_lc(mo, LC_SYMTAB, sizeof(*symlc));
dysymlc = add_lc(mo, LC_DYSYMTAB, sizeof(*dysymlc));
for(i = 0; i < s1->nb_loaded_dlls; i++) {
DLLReference *dllref = s1->loaded_dlls[i];
if (dllref->level == 0)
add_dylib(mo, dllref->name);
}
/* dyld requires a writable segment with classic Mach-O, but it ignores
zero-sized segments for this, so force to have some data. */
section_ptr_add(data_section, 1);
memset (mo->sk_to_sect, 0, sizeof(mo->sk_to_sect));
for (i = s1->nb_sections; i-- > 1;) {
int type, flags;
s = s1->sections[i];
type = s->sh_type;
flags = s->sh_flags;
sk = sk_unknown;
if (flags & SHF_ALLOC) {
switch (type) {
default: sk = sk_unknown; break;
case SHT_INIT_ARRAY: sk = sk_init; break;
case SHT_FINI_ARRAY: sk = sk_fini; break;
case SHT_NOBITS: sk = sk_bss; break;
case SHT_SYMTAB: sk = sk_discard; break;
case SHT_STRTAB: sk = s == stabstr_section ? sk_ro_data : sk_discard; break;
case SHT_RELX: sk = sk_discard; break;
case SHT_LINKEDIT: sk = sk_linkedit; break;
case SHT_PROGBITS:
if (s == s1->got)
sk = sk_nl_ptr;
else if (flags & SHF_EXECINSTR)
sk = sk_text;
else if (flags & SHF_WRITE)
sk = sk_rw_data;
else
sk = sk_ro_data;
break;
}
} else
sk = sk_discard;
s->prev = mo->sk_to_sect[sk].s;
mo->sk_to_sect[sk].s = s;
}
fileofs = 4096; /* leave space for mach-o headers */
curaddr = get_segment(mo, 1)->vmaddr;
curaddr += 4096;
seg = NULL;
numsec = 0;
mo->elfsectomacho = tcc_mallocz(sizeof(*mo->elfsectomacho) * s1->nb_sections);
for (sk = sk_unknown; sk < sk_last; sk++) {
struct section_64 *sec = NULL;
if (seg) {
seg->vmsize = curaddr - seg->vmaddr;
seg->filesize = fileofs - seg->fileoff;
}
if (skinfo[sk].seg && mo->sk_to_sect[sk].s) {
uint64_t al = 0;
int si;
seg = get_segment(mo, skinfo[sk].seg);
if (skinfo[sk].name) {
si = add_section(mo, &seg, skinfo[sk].name);
numsec++;
mo->lc[mo->seg2lc[skinfo[sk].seg]] = (struct load_command*)seg;
mo->sk_to_sect[sk].machosect = si;
sec = get_section(seg, si);
sec->flags = skinfo[sk].flags;
}
if (seg->vmaddr == -1) {
curaddr = (curaddr + 4095) & -4096;
seg->vmaddr = curaddr;
fileofs = (fileofs + 4095) & -4096;
seg->fileoff = fileofs;
}
for (s = mo->sk_to_sect[sk].s; s; s = s->prev) {
int a = exact_log2p1(s->sh_addralign);
if (a && al < (a - 1))
al = a - 1;
s->sh_size = s->data_offset;
}
if (sec)
sec->align = al;
al = 1ULL << al;
if (al > 4096)
tcc_warning("alignment > 4096"), sec->align = 12, al = 4096;
curaddr = (curaddr + al - 1) & -al;
fileofs = (fileofs + al - 1) & -al;
if (sec) {
sec->addr = curaddr;
sec->offset = fileofs;
}
for (s = mo->sk_to_sect[sk].s; s; s = s->prev) {
al = s->sh_addralign;
curaddr = (curaddr + al - 1) & -al;
dprintf("curaddr now 0x%lx\n", (long)curaddr);
s->sh_addr = curaddr;
curaddr += s->sh_size;
if (s->sh_type != SHT_NOBITS) {
fileofs = (fileofs + al - 1) & -al;
s->sh_offset = fileofs;
fileofs += s->sh_size;
dprintf("fileofs now %ld\n", (long)fileofs);
}
if (sec)
mo->elfsectomacho[s->sh_num] = numsec;
}
if (sec)
sec->size = curaddr - sec->addr;
}
if (DEBUG_MACHO)
for (s = mo->sk_to_sect[sk].s; s; s = s->prev) {
int type = s->sh_type;
int flags = s->sh_flags;
printf("%d section %-16s %-10s %09lx %04x %02d %s,%s,%s\n",
sk,
s->name,
type == SHT_PROGBITS ? "progbits" :
type == SHT_NOBITS ? "nobits" :
type == SHT_SYMTAB ? "symtab" :
type == SHT_STRTAB ? "strtab" :
type == SHT_INIT_ARRAY ? "init" :
type == SHT_FINI_ARRAY ? "fini" :
type == SHT_RELX ? "rel" : "???",
(long)s->sh_addr,
(unsigned)s->data_offset,
s->sh_addralign,
flags & SHF_ALLOC ? "alloc" : "",
flags & SHF_WRITE ? "write" : "",
flags & SHF_EXECINSTR ? "exec" : ""
);
}
}
if (seg) {
seg->vmsize = curaddr - seg->vmaddr;
seg->filesize = fileofs - seg->fileoff;
}
/* Fill symtab info */
symlc->symoff = mo->symtab->sh_offset;
symlc->nsyms = mo->symtab->data_offset / sizeof(struct nlist_64);
symlc->stroff = mo->strtab->sh_offset;
symlc->strsize = mo->strtab->data_offset;
dysymlc->iundefsym = mo->iundef == -1 ? symlc->nsyms : mo->iundef;
dysymlc->iextdefsym = mo->iextdef == -1 ? dysymlc->iundefsym : mo->iextdef;
dysymlc->ilocalsym = mo->ilocal == -1 ? dysymlc->iextdefsym : mo->ilocal;
dysymlc->nlocalsym = dysymlc->iextdefsym - dysymlc->ilocalsym;
dysymlc->nextdefsym = dysymlc->iundefsym - dysymlc->iextdefsym;
dysymlc->nundefsym = symlc->nsyms - dysymlc->iundefsym;
dysymlc->indirectsymoff = mo->indirsyms->sh_offset;
dysymlc->nindirectsyms = mo->indirsyms->data_offset / sizeof(uint32_t);
}
static void macho_write(TCCState *s1, struct macho *mo, FILE *fp)
{
int i, sk;
uint64_t fileofs = 0;
Section *s;
mo->mh.mh.magic = MH_MAGIC_64;
mo->mh.mh.cputype = 0x1000007; // x86_64
mo->mh.mh.cpusubtype = 0x80000003;// all | CPU_SUBTYPE_LIB64
mo->mh.mh.filetype = 2; // MH_EXECUTE
mo->mh.mh.flags = 4; // DYLDLINK
mo->mh.mh.ncmds = mo->nlc;
mo->mh.mh.sizeofcmds = 0;
for (i = 0; i < mo->nlc; i++)
mo->mh.mh.sizeofcmds += mo->lc[i]->cmdsize;
fwrite(&mo->mh, 1, sizeof(mo->mh), fp);
fileofs += sizeof(mo->mh);
for (i = 0; i < mo->nlc; i++) {
fwrite(mo->lc[i], 1, mo->lc[i]->cmdsize, fp);
fileofs += mo->lc[i]->cmdsize;
}
for (sk = sk_unknown; sk < sk_last; sk++) {
//struct segment_command_64 *seg;
if (!skinfo[sk].seg || !mo->sk_to_sect[sk].s)
continue;
/*seg =*/ get_segment(mo, skinfo[sk].seg);
for (s = mo->sk_to_sect[sk].s; s; s = s->prev) {
if (s->sh_type != SHT_NOBITS) {
while (fileofs < s->sh_offset)
fputc(0, fp), fileofs++;
if (s->sh_size) {
fwrite(s->data, 1, s->sh_size, fp);
fileofs += s->sh_size;
}
}
}
}
}
ST_FUNC int macho_output_file(TCCState *s1, const char *filename)
{
int fd, mode, file_type;
FILE *fp;
int i, ret = -1;
struct macho mo;
(void)memset(&mo, 0, sizeof(mo));
file_type = s1->output_type;
if (file_type == TCC_OUTPUT_OBJ)
mode = 0666;
else
mode = 0777;
unlink(filename);
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, mode);
if (fd < 0 || (fp = fdopen(fd, "wb")) == NULL) {
tcc_error_noabort("could not write '%s: %s'", filename, strerror(errno));
return -1;
}
if (s1->verbose)
printf("<- %s\n", filename);
tcc_add_runtime(s1);
resolve_common_syms(s1);
create_symtab(s1, &mo);
check_relocs(s1, &mo);
ret = check_symbols(s1, &mo);
if (!ret) {
collect_sections(s1, &mo);
relocate_syms(s1, s1->symtab, 0);
mo.ep->entryoff = get_sym_addr(s1, "main", 1, 1)
- get_segment(&mo, 1)->vmaddr;
if (s1->nb_errors)
goto do_ret;
relocate_sections(s1);
convert_symbols(s1, &mo);
macho_write(s1, &mo, fp);
}
do_ret:
for (i = 0; i < mo.nlc; i++)
tcc_free(mo.lc[i]);
tcc_free(mo.lc);
tcc_free(mo.elfsectomacho);
tcc_free(mo.e2msym);
fclose(fp);
return ret;
}
static uint32_t macho_swap32(uint32_t x)
{
return (x >> 24) | (x << 24) | ((x >> 8) & 0xff00) | ((x & 0xff00) << 8);
}
#define SWAP(x) (swap ? macho_swap32(x) : (x))
#define tbd_parse_movepast(s) \
(pos = (pos = strstr(pos, s)) ? pos + strlen(s) : NULL)
#define tbd_parse_movetoany(cs) (pos = strpbrk(pos, cs))
#define tbd_parse_skipws while (*pos && (*pos==' '||*pos=='\n')) ++pos
#define tbd_parse_tramplequote if(*pos=='\''||*pos=='"') tbd_parse_trample
#define tbd_parse_tramplespace if(*pos==' ') tbd_parse_trample
#define tbd_parse_trample *pos++=0
#ifdef TCC_IS_NATIVE
/* Looks for the active developer SDK set by xcode-select (or the default
one set during installation.) */
ST_FUNC void tcc_add_macos_sdkpath(TCCState* s)
{
char *sdkroot = NULL, *pos = NULL;
void* xcs = dlopen("libxcselect.dylib", RTLD_GLOBAL | RTLD_LAZY);
CString path;
int (*f)(unsigned int, char**) = dlsym(xcs, "xcselect_host_sdk_path");
cstr_new(&path);
if (f) f(1, &sdkroot);
if (sdkroot)
pos = strstr(sdkroot,"SDKs/MacOSX");
if (pos)
cstr_printf(&path, "%.*s.sdk/usr/lib", (int)(pos - sdkroot + 11), sdkroot);
/* must use free from libc directly */
#pragma push_macro("free")
#undef free
free(sdkroot);
#pragma pop_macro("free")
if (path.size)
tcc_add_library_path(s, (char*)path.data);
else
tcc_add_library_path(s,
"/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/lib"
":" "/Applications/Xcode.app/Developer/SDKs/MacOSX.sdk/usr/lib"
);
cstr_free(&path);
}
ST_FUNC const char* macho_tbd_soname(const char* filename) {
char *soname, *data, *pos;
const char *ret = filename;
int fd = open(filename,O_RDONLY);
if (fd<0) return ret;
pos = data = tcc_load_text(fd);
if (!tbd_parse_movepast("install-name: ")) goto the_end;
tbd_parse_skipws;
tbd_parse_tramplequote;
soname = pos;
if (!tbd_parse_movetoany("\n \"'")) goto the_end;
tbd_parse_trample;
ret = tcc_strdup(soname);
the_end:
tcc_free(data);
return ret;
}
#endif /* TCC_IS_NATIVE */
ST_FUNC int macho_load_tbd(TCCState* s1, int fd, const char* filename, int lev)
{
char *soname, *data, *pos;
int ret = -1;
pos = data = tcc_load_text(fd);
if (!tbd_parse_movepast("install-name: ")) goto the_end;
tbd_parse_skipws;
tbd_parse_tramplequote;
soname = pos;
if (!tbd_parse_movetoany("\n \"'")) goto the_end;
tbd_parse_trample;
ret = 0;
if (tcc_add_dllref(s1, soname, lev)->found)
goto the_end;
while(pos) {
char* sym = NULL;
int cont = 1;
if (!tbd_parse_movepast("symbols: ")) break;
if (!tbd_parse_movepast("[")) break;
while (cont) {
tbd_parse_skipws;
tbd_parse_tramplequote;
sym = pos;
if (!tbd_parse_movetoany(",] \"'")) break;
tbd_parse_tramplequote;
tbd_parse_tramplespace;
tbd_parse_skipws;
if (*pos==0||*pos==']') cont=0;
tbd_parse_trample;
set_elf_sym(s1->dynsymtab_section, 0, 0,
ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0, SHN_UNDEF, sym);
}
}
the_end:
tcc_free(data);
return ret;
}
ST_FUNC int macho_load_dll(TCCState * s1, int fd, const char* filename, int lev)
{
unsigned char buf[sizeof(struct mach_header_64)];
void *buf2;
uint32_t machofs = 0;
struct fat_header fh;
struct mach_header mh;
struct load_command *lc;
int i, swap = 0;
const char *soname = filename;
struct nlist_64 *symtab = 0;
uint32_t nsyms = 0;
char *strtab = 0;
uint32_t strsize = 0;
uint32_t iextdef = 0;
uint32_t nextdef = 0;
again:
if (full_read(fd, buf, sizeof(buf)) != sizeof(buf))
return -1;
memcpy(&fh, buf, sizeof(fh));
if (fh.magic == FAT_MAGIC || fh.magic == FAT_CIGAM) {
struct fat_arch *fa = load_data(fd, sizeof(fh),
fh.nfat_arch * sizeof(*fa));
swap = fh.magic == FAT_CIGAM;
for (i = 0; i < SWAP(fh.nfat_arch); i++)
if (SWAP(fa[i].cputype) == 0x01000007 /* CPU_TYPE_X86_64 */
&& SWAP(fa[i].cpusubtype) == 3) /* CPU_SUBTYPE_X86_ALL */
break;
if (i == SWAP(fh.nfat_arch)) {
tcc_free(fa);
return -1;
}
machofs = SWAP(fa[i].offset);
tcc_free(fa);
lseek(fd, machofs, SEEK_SET);
goto again;
} else if (fh.magic == FAT_MAGIC_64 || fh.magic == FAT_CIGAM_64) {
tcc_warning("%s: Mach-O fat 64bit files of type 0x%x not handled",
filename, fh.magic);
return -1;
}
memcpy(&mh, buf, sizeof(mh));
if (mh.magic != MH_MAGIC_64)
return -1;
dprintf("found Mach-O at %d\n", machofs);
buf2 = load_data(fd, machofs + sizeof(struct mach_header_64), mh.sizeofcmds);
for (i = 0, lc = buf2; i < mh.ncmds; i++) {
dprintf("lc %2d: 0x%08x\n", i, lc->cmd);
switch (lc->cmd) {
case LC_SYMTAB:
{
struct symtab_command *sc = (struct symtab_command*)lc;
nsyms = sc->nsyms;
symtab = load_data(fd, machofs + sc->symoff, nsyms * sizeof(*symtab));
strsize = sc->strsize;
strtab = load_data(fd, machofs + sc->stroff, strsize);
break;
}
case LC_ID_DYLIB:
{
struct dylib_command *dc = (struct dylib_command*)lc;
soname = (char*)lc + dc->name;
dprintf(" ID_DYLIB %d 0x%x 0x%x %s\n",