1 /* simple-object-mach-o.c -- routines to manipulate Mach-O object files.
2 Copyright (C) 2010-2024 Free Software Foundation, Inc.
3 Written by Ian Lance Taylor, Google.
4
5 This program is free software; you can redistribute it and/or modify it
6 under the terms of the GNU General Public License as published by the
7 Free Software Foundation; either version 2, or (at your option) any
8 later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, 51 Franklin Street - Fifth Floor,
18 Boston, MA 02110-1301, USA. */
19
20 #include "config.h"
21 #include "libiberty.h"
22 #include "simple-object.h"
23
24 #include <stddef.h>
25
26 #ifdef HAVE_STDLIB_H
27 #include <stdlib.h>
28 #endif
29
30 #ifdef HAVE_STDINT_H
31 #include <stdint.h>
32 #endif
33
34 #ifdef HAVE_STRING_H
35 #include <string.h>
36 #endif
37
38 #ifdef HAVE_INTTYPES_H
39 #include <inttypes.h>
40 #endif
41
42 #include "simple-object-common.h"
43
44 /* Mach-O structures and constants. */
45
46 /* Mach-O header (32-bit version). */
47
48 struct mach_o_header_32
49 {
50 unsigned char magic[4]; /* Magic number. */
51 unsigned char cputype[4]; /* CPU that this object is for. */
52 unsigned char cpusubtype[4]; /* CPU subtype. */
53 unsigned char filetype[4]; /* Type of file. */
54 unsigned char ncmds[4]; /* Number of load commands. */
55 unsigned char sizeofcmds[4]; /* Total size of load commands. */
56 unsigned char flags[4]; /* Flags for special featues. */
57 };
58
59 /* Mach-O header (64-bit version). */
60
61 struct mach_o_header_64
62 {
63 unsigned char magic[4]; /* Magic number. */
64 unsigned char cputype[4]; /* CPU that this object is for. */
65 unsigned char cpusubtype[4]; /* CPU subtype. */
66 unsigned char filetype[4]; /* Type of file. */
67 unsigned char ncmds[4]; /* Number of load commands. */
68 unsigned char sizeofcmds[4]; /* Total size of load commands. */
69 unsigned char flags[4]; /* Flags for special featues. */
70 unsigned char reserved[4]; /* Reserved. Duh. */
71 };
72
73 /* For magic field in header. */
74
75 #define MACH_O_MH_MAGIC 0xfeedface
76 #define MACH_O_MH_MAGIC_64 0xfeedfacf
77
78 /* For filetype field in header. */
79
80 #define MACH_O_MH_OBJECT 0x01
81
82 /* A Mach-O file is a list of load commands. This is the header of a
83 load command. */
84
85 struct mach_o_load_command
86 {
87 unsigned char cmd[4]; /* The type of load command. */
88 unsigned char cmdsize[4]; /* Size in bytes of entire command. */
89 };
90
91 /* For cmd field in load command. */
92
93 #define MACH_O_LC_SEGMENT 0x01
94 #define MACH_O_LC_SEGMENT_64 0x19
95
96 /* LC_SEGMENT load command. */
97
98 struct mach_o_segment_command_32
99 {
100 unsigned char cmd[4]; /* The type of load command (LC_SEGMENT). */
101 unsigned char cmdsize[4]; /* Size in bytes of entire command. */
102 unsigned char segname[16]; /* Name of this segment. */
103 unsigned char vmaddr[4]; /* Virtual memory address of this segment. */
104 unsigned char vmsize[4]; /* Size there, in bytes. */
105 unsigned char fileoff[4]; /* Offset in bytes of the data to be mapped. */
106 unsigned char filesize[4]; /* Size in bytes on disk. */
107 unsigned char maxprot[4]; /* Maximum permitted vmem protection. */
108 unsigned char initprot[4]; /* Initial vmem protection. */
109 unsigned char nsects[4]; /* Number of sections in this segment. */
110 unsigned char flags[4]; /* Flags that affect the loading. */
111 };
112
113 /* LC_SEGMENT_64 load command. */
114
115 struct mach_o_segment_command_64
116 {
117 unsigned char cmd[4]; /* The type of load command (LC_SEGMENT_64). */
118 unsigned char cmdsize[4]; /* Size in bytes of entire command. */
119 unsigned char segname[16]; /* Name of this segment. */
120 unsigned char vmaddr[8]; /* Virtual memory address of this segment. */
121 unsigned char vmsize[8]; /* Size there, in bytes. */
122 unsigned char fileoff[8]; /* Offset in bytes of the data to be mapped. */
123 unsigned char filesize[8]; /* Size in bytes on disk. */
124 unsigned char maxprot[4]; /* Maximum permitted vmem protection. */
125 unsigned char initprot[4]; /* Initial vmem protection. */
126 unsigned char nsects[4]; /* Number of sections in this segment. */
127 unsigned char flags[4]; /* Flags that affect the loading. */
128 };
129
130 /* 32-bit section header. */
131
132 struct mach_o_section_32
133 {
134 unsigned char sectname[16]; /* Section name. */
135 unsigned char segname[16]; /* Segment that the section belongs to. */
136 unsigned char addr[4]; /* Address of this section in memory. */
137 unsigned char size[4]; /* Size in bytes of this section. */
138 unsigned char offset[4]; /* File offset of this section. */
139 unsigned char align[4]; /* log2 of this section's alignment. */
140 unsigned char reloff[4]; /* File offset of this section's relocs. */
141 unsigned char nreloc[4]; /* Number of relocs for this section. */
142 unsigned char flags[4]; /* Section flags/attributes. */
143 unsigned char reserved1[4];
144 unsigned char reserved2[4];
145 };
146
147 /* 64-bit section header. */
148
149 struct mach_o_section_64
150 {
151 unsigned char sectname[16]; /* Section name. */
152 unsigned char segname[16]; /* Segment that the section belongs to. */
153 unsigned char addr[8]; /* Address of this section in memory. */
154 unsigned char size[8]; /* Size in bytes of this section. */
155 unsigned char offset[4]; /* File offset of this section. */
156 unsigned char align[4]; /* log2 of this section's alignment. */
157 unsigned char reloff[4]; /* File offset of this section's relocs. */
158 unsigned char nreloc[4]; /* Number of relocs for this section. */
159 unsigned char flags[4]; /* Section flags/attributes. */
160 unsigned char reserved1[4];
161 unsigned char reserved2[4];
162 unsigned char reserved3[4];
163 };
164
165 /* Flags for Mach-O sections. */
166
167 #define MACH_O_S_ATTR_DEBUG 0x02000000
168
169 /* The length of a segment or section name. */
170
171 #define MACH_O_NAME_LEN (16)
172
173 /* A GNU specific extension for long section names. */
174
175 #define GNU_SECTION_NAMES "__section_names"
176
177 /* A GNU-specific extension to wrap multiple sections using three
178 mach-o sections within a given segment. The section '__wrapper_sects'
179 is subdivided according to the index '__wrapper_index' and each sub
180 sect is named according to the names supplied in '__wrapper_names'. */
181
182 #define GNU_WRAPPER_SECTS "__wrapper_sects"
183 #define GNU_WRAPPER_INDEX "__wrapper_index"
184 #define GNU_WRAPPER_NAMES "__wrapper_names"
185
186 /* Private data for an simple_object_read. */
187
188 struct simple_object_mach_o_read
189 {
190 /* User specified segment name. */
191 char *segment_name;
192 /* Magic number. */
193 unsigned int magic;
194 /* Whether this file is big-endian. */
195 int is_big_endian;
196 /* CPU type from header. */
197 unsigned int cputype;
198 /* CPU subtype from header. */
199 unsigned int cpusubtype;
200 /* Number of commands, from header. */
201 unsigned int ncmds;
202 /* Flags from header. */
203 unsigned int flags;
204 /* Reserved field from header, only used on 64-bit. */
205 unsigned int reserved;
206 };
207
208 /* Private data for an simple_object_attributes. */
209
210 struct simple_object_mach_o_attributes
211 {
212 /* Magic number. */
213 unsigned int magic;
214 /* Whether this file is big-endian. */
215 int is_big_endian;
216 /* CPU type from header. */
217 unsigned int cputype;
218 /* CPU subtype from header. */
219 unsigned int cpusubtype;
220 /* Flags from header. */
221 unsigned int flags;
222 /* Reserved field from header, only used on 64-bit. */
223 unsigned int reserved;
224 };
225
226 /* See if we have a Mach-O MH_OBJECT file:
227
228 A standard MH_OBJECT (from as) will have three load commands:
229 0 - LC_SEGMENT/LC_SEGMENT64
230 1 - LC_SYMTAB
231 2 - LC_DYSYMTAB
232
233 The LC_SEGMENT/LC_SEGMENT64 will introduce a single anonymous segment
234 containing all the sections.
235
236 Files written by simple-object will have only the segment command
237 (no symbol tables). */
238
239 static void *
simple_object_mach_o_match(unsigned char header[SIMPLE_OBJECT_MATCH_HEADER_LEN],int descriptor,off_t offset,const char * segment_name,const char ** errmsg,int * err)240 simple_object_mach_o_match (
241 unsigned char header[SIMPLE_OBJECT_MATCH_HEADER_LEN],
242 int descriptor,
243 off_t offset,
244 const char *segment_name,
245 const char **errmsg,
246 int *err)
247 {
248 unsigned int magic;
249 int is_big_endian;
250 unsigned int (*fetch_32) (const unsigned char *);
251 unsigned int filetype;
252 struct simple_object_mach_o_read *omr;
253 unsigned char buf[sizeof (struct mach_o_header_64)];
254 unsigned char *b;
255
256 magic = simple_object_fetch_big_32 (header);
257 if (magic == MACH_O_MH_MAGIC || magic == MACH_O_MH_MAGIC_64)
258 is_big_endian = 1;
259 else
260 {
261 magic = simple_object_fetch_little_32 (header);
262 if (magic == MACH_O_MH_MAGIC || magic == MACH_O_MH_MAGIC_64)
263 is_big_endian = 0;
264 else
265 {
266 *errmsg = NULL;
267 *err = 0;
268 return NULL;
269 }
270 }
271
272 #ifndef UNSIGNED_64BIT_TYPE
273 if (magic == MACH_O_MH_MAGIC_64)
274 {
275 *errmsg = "64-bit Mach-O objects not supported";
276 *err = 0;
277 return NULL;
278 }
279 #endif
280
281 /* We require the user to provide a segment name. This is
282 unfortunate but I don't see any good choices here. */
283
284 if (segment_name == NULL)
285 {
286 *errmsg = "Mach-O file found but no segment name specified";
287 *err = 0;
288 return NULL;
289 }
290
291 if (strlen (segment_name) > MACH_O_NAME_LEN)
292 {
293 *errmsg = "Mach-O segment name too long";
294 *err = 0;
295 return NULL;
296 }
297
298 /* The 32-bit and 64-bit headers are similar enough that we can use
299 the same code. */
300
301 fetch_32 = (is_big_endian
302 ? simple_object_fetch_big_32
303 : simple_object_fetch_little_32);
304
305 if (!simple_object_internal_read (descriptor, offset, buf,
306 (magic == MACH_O_MH_MAGIC
307 ? sizeof (struct mach_o_header_32)
308 : sizeof (struct mach_o_header_64)),
309 errmsg, err))
310 return NULL;
311
312 b = &buf[0];
313
314 filetype = (*fetch_32) (b + offsetof (struct mach_o_header_32, filetype));
315 if (filetype != MACH_O_MH_OBJECT)
316 {
317 *errmsg = "Mach-O file is not object file";
318 *err = 0;
319 return NULL;
320 }
321
322 omr = XNEW (struct simple_object_mach_o_read);
323 omr->segment_name = xstrdup (segment_name);
324 omr->magic = magic;
325 omr->is_big_endian = is_big_endian;
326 omr->cputype = (*fetch_32) (b + offsetof (struct mach_o_header_32, cputype));
327 omr->cpusubtype = (*fetch_32) (b
328 + offsetof (struct mach_o_header_32,
329 cpusubtype));
330 omr->ncmds = (*fetch_32) (b + offsetof (struct mach_o_header_32, ncmds));
331 omr->flags = (*fetch_32) (b + offsetof (struct mach_o_header_32, flags));
332 if (magic == MACH_O_MH_MAGIC)
333 omr->reserved = 0;
334 else
335 omr->reserved = (*fetch_32) (b
336 + offsetof (struct mach_o_header_64,
337 reserved));
338
339 return (void *) omr;
340 }
341
342 /* Get the file offset and size from a section header. */
343
344 static void
simple_object_mach_o_section_info(int is_big_endian,int is_32,const unsigned char * sechdr,off_t * offset,size_t * size)345 simple_object_mach_o_section_info (int is_big_endian, int is_32,
346 const unsigned char *sechdr, off_t *offset,
347 size_t *size)
348 {
349 unsigned int (*fetch_32) (const unsigned char *);
350 ulong_type (*fetch_64) (const unsigned char *);
351
352 fetch_32 = (is_big_endian
353 ? simple_object_fetch_big_32
354 : simple_object_fetch_little_32);
355
356 fetch_64 = NULL;
357 #ifdef UNSIGNED_64BIT_TYPE
358 fetch_64 = (is_big_endian
359 ? simple_object_fetch_big_64
360 : simple_object_fetch_little_64);
361 #endif
362
363 if (is_32)
364 {
365 *offset = fetch_32 (sechdr
366 + offsetof (struct mach_o_section_32, offset));
367 *size = fetch_32 (sechdr
368 + offsetof (struct mach_o_section_32, size));
369 }
370 else
371 {
372 *offset = fetch_32 (sechdr
373 + offsetof (struct mach_o_section_64, offset));
374 *size = fetch_64 (sechdr
375 + offsetof (struct mach_o_section_64, size));
376 }
377 }
378
379 /* Handle a segment in a Mach-O Object file.
380
381 This will callback to the function pfn for each "section found" the meaning
382 of which depends on gnu extensions to mach-o:
383
384 If we find mach-o sections (with the segment name as specified) which also
385 contain: a 'sects' wrapper, an index, and a name table, we expand this into
386 as many sections as are specified in the index. In this case, there will
387 be a callback for each of these.
388
389 We will also allow an extension that permits long names (more than 16
390 characters) to be used with mach-o. In this case, the section name has
391 a specific format embedding an index into a name table, and the file must
392 contain such name table.
393
394 Return 1 if we should continue, 0 if the caller should return. */
395
396 #define SOMO_SECTS_PRESENT 0x01
397 #define SOMO_INDEX_PRESENT 0x02
398 #define SOMO_NAMES_PRESENT 0x04
399 #define SOMO_LONGN_PRESENT 0x08
400 #define SOMO_WRAPPING (SOMO_SECTS_PRESENT | SOMO_INDEX_PRESENT \
401 | SOMO_NAMES_PRESENT)
402
403 static int
simple_object_mach_o_segment(simple_object_read * sobj,off_t offset,const unsigned char * segbuf,int (* pfn)(void *,const char *,off_t offset,off_t length),void * data,const char ** errmsg,int * err)404 simple_object_mach_o_segment (simple_object_read *sobj, off_t offset,
405 const unsigned char *segbuf,
406 int (*pfn) (void *, const char *, off_t offset,
407 off_t length),
408 void *data,
409 const char **errmsg, int *err)
410 {
411 struct simple_object_mach_o_read *omr =
412 (struct simple_object_mach_o_read *) sobj->data;
413 unsigned int (*fetch_32) (const unsigned char *);
414 int is_32;
415 size_t seghdrsize;
416 size_t sechdrsize;
417 size_t segname_offset;
418 size_t sectname_offset;
419 unsigned int nsects;
420 unsigned char *secdata;
421 unsigned int i;
422 unsigned int gnu_sections_found;
423 unsigned int strtab_index;
424 unsigned int index_index;
425 unsigned int nametab_index;
426 unsigned int sections_index;
427 char *strtab;
428 char *nametab;
429 unsigned char *index;
430 size_t strtab_size;
431 size_t nametab_size;
432 size_t index_size;
433 unsigned int n_wrapped_sects;
434 size_t wrapper_sect_size;
435 off_t wrapper_sect_offset = 0;
436
437 fetch_32 = (omr->is_big_endian
438 ? simple_object_fetch_big_32
439 : simple_object_fetch_little_32);
440
441 is_32 = omr->magic == MACH_O_MH_MAGIC;
442
443 if (is_32)
444 {
445 seghdrsize = sizeof (struct mach_o_segment_command_32);
446 sechdrsize = sizeof (struct mach_o_section_32);
447 segname_offset = offsetof (struct mach_o_section_32, segname);
448 sectname_offset = offsetof (struct mach_o_section_32, sectname);
449 nsects = (*fetch_32) (segbuf
450 + offsetof (struct mach_o_segment_command_32,
451 nsects));
452 }
453 else
454 {
455 seghdrsize = sizeof (struct mach_o_segment_command_64);
456 sechdrsize = sizeof (struct mach_o_section_64);
457 segname_offset = offsetof (struct mach_o_section_64, segname);
458 sectname_offset = offsetof (struct mach_o_section_64, sectname);
459 nsects = (*fetch_32) (segbuf
460 + offsetof (struct mach_o_segment_command_64,
461 nsects));
462 }
463
464 /* Fetch the section headers from the segment command. */
465
466 secdata = XNEWVEC (unsigned char, nsects * sechdrsize);
467 if (!simple_object_internal_read (sobj->descriptor, offset + seghdrsize,
468 secdata, nsects * sechdrsize, errmsg, err))
469 {
470 XDELETEVEC (secdata);
471 return 0;
472 }
473
474 /* Scan for special sections that signal GNU extensions to the format. */
475
476 gnu_sections_found = 0;
477 index_index = nsects;
478 sections_index = nsects;
479 strtab_index = nsects;
480 nametab_index = nsects;
481 for (i = 0; i < nsects; ++i)
482 {
483 size_t nameoff;
484
485 nameoff = i * sechdrsize + segname_offset;
486 if (strcmp ((char *) secdata + nameoff, omr->segment_name) != 0)
487 continue;
488
489 nameoff = i * sechdrsize + sectname_offset;
490 if (strcmp ((char *) secdata + nameoff, GNU_WRAPPER_NAMES) == 0)
491 {
492 nametab_index = i;
493 gnu_sections_found |= SOMO_NAMES_PRESENT;
494 }
495 else if (strcmp ((char *) secdata + nameoff, GNU_WRAPPER_INDEX) == 0)
496 {
497 index_index = i;
498 gnu_sections_found |= SOMO_INDEX_PRESENT;
499 }
500 else if (strcmp ((char *) secdata + nameoff, GNU_WRAPPER_SECTS) == 0)
501 {
502 sections_index = i;
503 gnu_sections_found |= SOMO_SECTS_PRESENT;
504 }
505 else if (strcmp ((char *) secdata + nameoff, GNU_SECTION_NAMES) == 0)
506 {
507 strtab_index = i;
508 gnu_sections_found |= SOMO_LONGN_PRESENT;
509 }
510 }
511
512 /* If any of the special wrapper section components is present, then
513 they all should be. */
514
515 if ((gnu_sections_found & SOMO_WRAPPING) != 0)
516 {
517 off_t nametab_offset;
518 off_t index_offset;
519
520 if ((gnu_sections_found & SOMO_WRAPPING) != SOMO_WRAPPING)
521 {
522 *errmsg = "GNU Mach-o section wrapper: required section missing";
523 *err = 0; /* No useful errno. */
524 XDELETEVEC (secdata);
525 return 0;
526 }
527
528 /* Fetch the name table. */
529
530 simple_object_mach_o_section_info (omr->is_big_endian, is_32,
531 secdata + nametab_index * sechdrsize,
532 &nametab_offset, &nametab_size);
533 nametab = XNEWVEC (char, nametab_size);
534 if (!simple_object_internal_read (sobj->descriptor,
535 sobj->offset + nametab_offset,
536 (unsigned char *) nametab, nametab_size,
537 errmsg, err))
538 {
539 XDELETEVEC (nametab);
540 XDELETEVEC (secdata);
541 return 0;
542 }
543
544 /* Fetch the index. */
545
546 simple_object_mach_o_section_info (omr->is_big_endian, is_32,
547 secdata + index_index * sechdrsize,
548 &index_offset, &index_size);
549 index = XNEWVEC (unsigned char, index_size);
550 if (!simple_object_internal_read (sobj->descriptor,
551 sobj->offset + index_offset,
552 index, index_size,
553 errmsg, err))
554 {
555 XDELETEVEC (index);
556 XDELETEVEC (nametab);
557 XDELETEVEC (secdata);
558 return 0;
559 }
560
561 /* The index contains 4 unsigned ints per sub-section:
562 sub-section offset/length, sub-section name/length.
563 We fix this for both 32 and 64 bit mach-o for now, since
564 other fields limit the maximum size of an object to 4G. */
565 n_wrapped_sects = index_size / 16;
566
567 /* Get the parameters for the wrapper too. */
568 simple_object_mach_o_section_info (omr->is_big_endian, is_32,
569 secdata + sections_index * sechdrsize,
570 &wrapper_sect_offset,
571 &wrapper_sect_size);
572 }
573 else
574 {
575 index = NULL;
576 index_size = 0;
577 nametab = NULL;
578 nametab_size = 0;
579 n_wrapped_sects = 0;
580 }
581
582 /* If we have a long names section, fetch it. */
583
584 if ((gnu_sections_found & SOMO_LONGN_PRESENT) != 0)
585 {
586 off_t strtab_offset;
587
588 simple_object_mach_o_section_info (omr->is_big_endian, is_32,
589 secdata + strtab_index * sechdrsize,
590 &strtab_offset, &strtab_size);
591 strtab = XNEWVEC (char, strtab_size);
592 if (!simple_object_internal_read (sobj->descriptor,
593 sobj->offset + strtab_offset,
594 (unsigned char *) strtab, strtab_size,
595 errmsg, err))
596 {
597 XDELETEVEC (strtab);
598 XDELETEVEC (index);
599 XDELETEVEC (nametab);
600 XDELETEVEC (secdata);
601 return 0;
602 }
603 }
604 else
605 {
606 strtab = NULL;
607 strtab_size = 0;
608 strtab_index = nsects;
609 }
610
611 /* Process the sections. */
612
613 for (i = 0; i < nsects; ++i)
614 {
615 const unsigned char *sechdr;
616 char namebuf[MACH_O_NAME_LEN * 2 + 2];
617 char *name;
618 off_t secoffset;
619 size_t secsize;
620 int l;
621
622 sechdr = secdata + i * sechdrsize;
623
624 /* We've already processed the long section names. */
625
626 if ((gnu_sections_found & SOMO_LONGN_PRESENT) != 0
627 && i == strtab_index)
628 continue;
629
630 /* We only act on the segment named. */
631
632 if (strcmp ((char *) sechdr + segname_offset, omr->segment_name) != 0)
633 continue;
634
635 /* Process sections associated with the wrapper. */
636
637 if ((gnu_sections_found & SOMO_WRAPPING) != 0)
638 {
639 if (i == nametab_index || i == index_index)
640 continue;
641
642 if (i == sections_index)
643 {
644 unsigned int j;
645 for (j = 0; j < n_wrapped_sects; ++j)
646 {
647 unsigned int subsect_offset, subsect_length, name_offset;
648 subsect_offset = (*fetch_32) (index + 16 * j);
649 subsect_length = (*fetch_32) (index + 16 * j + 4);
650 name_offset = (*fetch_32) (index + 16 * j + 8);
651 /* We don't need the name_length yet. */
652
653 secoffset = wrapper_sect_offset + subsect_offset;
654 secsize = subsect_length;
655 name = nametab + name_offset;
656
657 if (!(*pfn) (data, name, secoffset, secsize))
658 {
659 *errmsg = NULL;
660 *err = 0;
661 XDELETEVEC (index);
662 XDELETEVEC (nametab);
663 XDELETEVEC (strtab);
664 XDELETEVEC (secdata);
665 return 0;
666 }
667 }
668 continue;
669 }
670 }
671
672 if ((gnu_sections_found & SOMO_LONGN_PRESENT) != 0)
673 {
674 memcpy (namebuf, sechdr + sectname_offset, MACH_O_NAME_LEN);
675 namebuf[MACH_O_NAME_LEN] = '\0';
676
677 name = &namebuf[0];
678 if (strtab != NULL && name[0] == '_' && name[1] == '_')
679 {
680 unsigned long stringoffset;
681
682 if (sscanf (name + 2, "%08lX", &stringoffset) == 1)
683 {
684 if (stringoffset >= strtab_size)
685 {
686 *errmsg = "section name offset out of range";
687 *err = 0;
688 XDELETEVEC (index);
689 XDELETEVEC (nametab);
690 XDELETEVEC (strtab);
691 XDELETEVEC (secdata);
692 return 0;
693 }
694
695 name = strtab + stringoffset;
696 }
697 }
698 }
699 else
700 {
701 /* Otherwise, make a name like __segment,__section as per the
702 convention in mach-o asm. */
703 name = &namebuf[0];
704 memcpy (namebuf, (char *) sechdr + segname_offset, MACH_O_NAME_LEN);
705 namebuf[MACH_O_NAME_LEN] = '\0';
706 l = strlen (namebuf);
707 namebuf[l] = ',';
708 memcpy (namebuf + l + 1, (char *) sechdr + sectname_offset,
709 MACH_O_NAME_LEN);
710 namebuf[l + 1 + MACH_O_NAME_LEN] = '\0';
711 }
712
713 simple_object_mach_o_section_info (omr->is_big_endian, is_32, sechdr,
714 &secoffset, &secsize);
715
716 if (!(*pfn) (data, name, secoffset, secsize))
717 {
718 *errmsg = NULL;
719 *err = 0;
720 XDELETEVEC (index);
721 XDELETEVEC (nametab);
722 XDELETEVEC (strtab);
723 XDELETEVEC (secdata);
724 return 0;
725 }
726 }
727
728 XDELETEVEC (index);
729 XDELETEVEC (nametab);
730 XDELETEVEC (strtab);
731 XDELETEVEC (secdata);
732
733 return 1;
734 }
735
736 /* Find all sections in a Mach-O file. */
737
738 static const char *
simple_object_mach_o_find_sections(simple_object_read * sobj,int (* pfn)(void *,const char *,off_t offset,off_t length),void * data,int * err)739 simple_object_mach_o_find_sections (simple_object_read *sobj,
740 int (*pfn) (void *, const char *,
741 off_t offset, off_t length),
742 void *data,
743 int *err)
744 {
745 struct simple_object_mach_o_read *omr =
746 (struct simple_object_mach_o_read *) sobj->data;
747 off_t offset;
748 size_t seghdrsize;
749 unsigned int (*fetch_32) (const unsigned char *);
750 const char *errmsg;
751 unsigned int i;
752
753 if (omr->magic == MACH_O_MH_MAGIC)
754 {
755 offset = sizeof (struct mach_o_header_32);
756 seghdrsize = sizeof (struct mach_o_segment_command_32);
757 }
758 else
759 {
760 offset = sizeof (struct mach_o_header_64);
761 seghdrsize = sizeof (struct mach_o_segment_command_64);
762 }
763
764 fetch_32 = (omr->is_big_endian
765 ? simple_object_fetch_big_32
766 : simple_object_fetch_little_32);
767
768 for (i = 0; i < omr->ncmds; ++i)
769 {
770 unsigned char loadbuf[sizeof (struct mach_o_load_command)];
771 unsigned int cmd;
772 unsigned int cmdsize;
773
774 if (!simple_object_internal_read (sobj->descriptor,
775 sobj->offset + offset,
776 loadbuf,
777 sizeof (struct mach_o_load_command),
778 &errmsg, err))
779 return errmsg;
780
781 cmd = (*fetch_32) (loadbuf + offsetof (struct mach_o_load_command, cmd));
782 cmdsize = (*fetch_32) (loadbuf
783 + offsetof (struct mach_o_load_command, cmdsize));
784
785 if (cmd == MACH_O_LC_SEGMENT || cmd == MACH_O_LC_SEGMENT_64)
786 {
787 unsigned char segbuf[sizeof (struct mach_o_segment_command_64)];
788 int r;
789
790 if (!simple_object_internal_read (sobj->descriptor,
791 sobj->offset + offset,
792 segbuf, seghdrsize, &errmsg, err))
793 return errmsg;
794
795 r = simple_object_mach_o_segment (sobj, offset, segbuf, pfn,
796 data, &errmsg, err);
797 if (!r)
798 return errmsg;
799 }
800
801 offset += cmdsize;
802 }
803
804 return NULL;
805 }
806
807 /* Fetch the attributes for an simple_object_read. */
808
809 static void *
simple_object_mach_o_fetch_attributes(simple_object_read * sobj,const char ** errmsg ATTRIBUTE_UNUSED,int * err ATTRIBUTE_UNUSED)810 simple_object_mach_o_fetch_attributes (simple_object_read *sobj,
811 const char **errmsg ATTRIBUTE_UNUSED,
812 int *err ATTRIBUTE_UNUSED)
813 {
814 struct simple_object_mach_o_read *omr =
815 (struct simple_object_mach_o_read *) sobj->data;
816 struct simple_object_mach_o_attributes *ret;
817
818 ret = XNEW (struct simple_object_mach_o_attributes);
819 ret->magic = omr->magic;
820 ret->is_big_endian = omr->is_big_endian;
821 ret->cputype = omr->cputype;
822 ret->cpusubtype = omr->cpusubtype;
823 ret->flags = omr->flags;
824 ret->reserved = omr->reserved;
825 return ret;
826 }
827
828 /* Release the private data for an simple_object_read. */
829
830 static void
simple_object_mach_o_release_read(void * data)831 simple_object_mach_o_release_read (void *data)
832 {
833 struct simple_object_mach_o_read *omr =
834 (struct simple_object_mach_o_read *) data;
835
836 free (omr->segment_name);
837 XDELETE (omr);
838 }
839
840 /* Compare two attributes structures. */
841
842 static const char *
simple_object_mach_o_attributes_merge(void * todata,void * fromdata,int * err)843 simple_object_mach_o_attributes_merge (void *todata, void *fromdata, int *err)
844 {
845 struct simple_object_mach_o_attributes *to =
846 (struct simple_object_mach_o_attributes *) todata;
847 struct simple_object_mach_o_attributes *from =
848 (struct simple_object_mach_o_attributes *) fromdata;
849
850 if (to->magic != from->magic
851 || to->is_big_endian != from->is_big_endian
852 || to->cputype != from->cputype)
853 {
854 *err = 0;
855 return "Mach-O object format mismatch";
856 }
857 return NULL;
858 }
859
860 /* Release the private data for an attributes structure. */
861
862 static void
simple_object_mach_o_release_attributes(void * data)863 simple_object_mach_o_release_attributes (void *data)
864 {
865 XDELETE (data);
866 }
867
868 /* Prepare to write out a file. */
869
870 static void *
simple_object_mach_o_start_write(void * attributes_data,const char ** errmsg ATTRIBUTE_UNUSED,int * err ATTRIBUTE_UNUSED)871 simple_object_mach_o_start_write (void *attributes_data,
872 const char **errmsg ATTRIBUTE_UNUSED,
873 int *err ATTRIBUTE_UNUSED)
874 {
875 struct simple_object_mach_o_attributes *attrs =
876 (struct simple_object_mach_o_attributes *) attributes_data;
877 struct simple_object_mach_o_attributes *ret;
878
879 /* We're just going to record the attributes, but we need to make a
880 copy because the user may delete them. */
881 ret = XNEW (struct simple_object_mach_o_attributes);
882 *ret = *attrs;
883 return ret;
884 }
885
886 /* Write out the header of a Mach-O file. */
887
888 static int
simple_object_mach_o_write_header(simple_object_write * sobj,int descriptor,size_t nsects,const char ** errmsg,int * err)889 simple_object_mach_o_write_header (simple_object_write *sobj, int descriptor,
890 size_t nsects, const char **errmsg,
891 int *err)
892 {
893 struct simple_object_mach_o_attributes *attrs =
894 (struct simple_object_mach_o_attributes *) sobj->data;
895 void (*set_32) (unsigned char *, unsigned int);
896 unsigned char hdrbuf[sizeof (struct mach_o_header_64)];
897 unsigned char *hdr;
898 size_t wrsize;
899
900 set_32 = (attrs->is_big_endian
901 ? simple_object_set_big_32
902 : simple_object_set_little_32);
903
904 memset (hdrbuf, 0, sizeof hdrbuf);
905
906 /* The 32-bit and 64-bit headers start out the same. */
907
908 hdr = &hdrbuf[0];
909 set_32 (hdr + offsetof (struct mach_o_header_32, magic), attrs->magic);
910 set_32 (hdr + offsetof (struct mach_o_header_32, cputype), attrs->cputype);
911 set_32 (hdr + offsetof (struct mach_o_header_32, cpusubtype),
912 attrs->cpusubtype);
913 set_32 (hdr + offsetof (struct mach_o_header_32, filetype), MACH_O_MH_OBJECT);
914 set_32 (hdr + offsetof (struct mach_o_header_32, ncmds), 1);
915 set_32 (hdr + offsetof (struct mach_o_header_32, flags), attrs->flags);
916 if (attrs->magic == MACH_O_MH_MAGIC)
917 {
918 wrsize = sizeof (struct mach_o_header_32);
919 set_32 (hdr + offsetof (struct mach_o_header_32, sizeofcmds),
920 (sizeof (struct mach_o_segment_command_32)
921 + nsects * sizeof (struct mach_o_section_32)));
922 }
923 else
924 {
925 set_32 (hdr + offsetof (struct mach_o_header_64, sizeofcmds),
926 (sizeof (struct mach_o_segment_command_64)
927 + nsects * sizeof (struct mach_o_section_64)));
928 set_32 (hdr + offsetof (struct mach_o_header_64, reserved),
929 attrs->reserved);
930 wrsize = sizeof (struct mach_o_header_64);
931 }
932
933 return simple_object_internal_write (descriptor, 0, hdrbuf, wrsize,
934 errmsg, err);
935 }
936
937 /* Write a Mach-O section header. */
938
939 static int
simple_object_mach_o_write_section_header(simple_object_write * sobj,int descriptor,size_t sechdr_offset,const char * name,const char * segn,size_t secaddr,size_t secsize,size_t offset,unsigned int align,const char ** errmsg,int * err)940 simple_object_mach_o_write_section_header (simple_object_write *sobj,
941 int descriptor,
942 size_t sechdr_offset,
943 const char *name, const char *segn,
944 size_t secaddr, size_t secsize,
945 size_t offset, unsigned int align,
946 const char **errmsg, int *err)
947 {
948 struct simple_object_mach_o_attributes *attrs =
949 (struct simple_object_mach_o_attributes *) sobj->data;
950 void (*set_32) (unsigned char *, unsigned int);
951 unsigned char hdrbuf[sizeof (struct mach_o_section_64)];
952 unsigned char *hdr;
953 size_t sechdrsize;
954
955 set_32 = (attrs->is_big_endian
956 ? simple_object_set_big_32
957 : simple_object_set_little_32);
958
959 memset (hdrbuf, 0, sizeof hdrbuf);
960
961 hdr = &hdrbuf[0];
962 if (attrs->magic == MACH_O_MH_MAGIC)
963 {
964 strncpy ((char *) hdr + offsetof (struct mach_o_section_32, sectname),
965 name, MACH_O_NAME_LEN);
966 strncpy ((char *) hdr + offsetof (struct mach_o_section_32, segname),
967 segn, MACH_O_NAME_LEN);
968 set_32 (hdr + offsetof (struct mach_o_section_32, addr), secaddr);
969 set_32 (hdr + offsetof (struct mach_o_section_32, size), secsize);
970 set_32 (hdr + offsetof (struct mach_o_section_32, offset), offset);
971 set_32 (hdr + offsetof (struct mach_o_section_32, align), align);
972 /* reloff left as zero. */
973 /* nreloc left as zero. */
974 set_32 (hdr + offsetof (struct mach_o_section_32, flags),
975 MACH_O_S_ATTR_DEBUG);
976 /* reserved1 left as zero. */
977 /* reserved2 left as zero. */
978 sechdrsize = sizeof (struct mach_o_section_32);
979 }
980 else
981 {
982 #ifdef UNSIGNED_64BIT_TYPE
983 void (*set_64) (unsigned char *, ulong_type);
984
985 set_64 = (attrs->is_big_endian
986 ? simple_object_set_big_64
987 : simple_object_set_little_64);
988
989 strncpy ((char *) hdr + offsetof (struct mach_o_section_64, sectname),
990 name, MACH_O_NAME_LEN);
991 strncpy ((char *) hdr + offsetof (struct mach_o_section_64, segname),
992 segn, MACH_O_NAME_LEN);
993 set_64 (hdr + offsetof (struct mach_o_section_64, addr), secaddr);
994 set_64 (hdr + offsetof (struct mach_o_section_64, size), secsize);
995 set_32 (hdr + offsetof (struct mach_o_section_64, offset), offset);
996 set_32 (hdr + offsetof (struct mach_o_section_64, align), align);
997 /* reloff left as zero. */
998 /* nreloc left as zero. */
999 set_32 (hdr + offsetof (struct mach_o_section_64, flags),
1000 MACH_O_S_ATTR_DEBUG);
1001 /* reserved1 left as zero. */
1002 /* reserved2 left as zero. */
1003 /* reserved3 left as zero. */
1004 #endif
1005 sechdrsize = sizeof (struct mach_o_section_64);
1006 }
1007
1008 return simple_object_internal_write (descriptor, sechdr_offset, hdr,
1009 sechdrsize, errmsg, err);
1010 }
1011
1012 /* Write out the single (anonymous) segment containing the sections of a Mach-O
1013 Object file.
1014
1015 As a GNU extension to mach-o, when the caller specifies a segment name in
1016 sobj->segment_name, all the sections passed will be output under a single
1017 mach-o section header. The caller's sections are indexed within this
1018 'wrapper' section by a table stored in a second mach-o section. Finally,
1019 arbitrary length section names are permitted by the extension and these are
1020 stored in a table in a third mach-o section.
1021
1022 Note that this is only likely to make any sense for the __GNU_LTO segment
1023 at present.
1024
1025 If the wrapper extension is not in force, we assume that the section name
1026 is in the form __SEGMENT_NAME,__section_name as per Mach-O asm. */
1027
1028 static int
simple_object_mach_o_write_segment(simple_object_write * sobj,int descriptor,size_t * nsects,const char ** errmsg,int * err)1029 simple_object_mach_o_write_segment (simple_object_write *sobj, int descriptor,
1030 size_t *nsects, const char **errmsg,
1031 int *err)
1032 {
1033 struct simple_object_mach_o_attributes *attrs =
1034 (struct simple_object_mach_o_attributes *) sobj->data;
1035 void (*set_32) (unsigned char *, unsigned int);
1036 size_t hdrsize;
1037 size_t seghdrsize;
1038 size_t sechdrsize;
1039 size_t cmdsize;
1040 size_t offset;
1041 size_t sechdr_offset;
1042 size_t secaddr;
1043 unsigned int name_offset;
1044 simple_object_write_section *section;
1045 unsigned char hdrbuf[sizeof (struct mach_o_segment_command_64)];
1046 unsigned char *hdr;
1047 size_t nsects_in;
1048 unsigned int *index;
1049 char *snames;
1050 unsigned int sect;
1051
1052 set_32 = (attrs->is_big_endian
1053 ? simple_object_set_big_32
1054 : simple_object_set_little_32);
1055
1056 /* Write out the sections first. */
1057
1058 if (attrs->magic == MACH_O_MH_MAGIC)
1059 {
1060 hdrsize = sizeof (struct mach_o_header_32);
1061 seghdrsize = sizeof (struct mach_o_segment_command_32);
1062 sechdrsize = sizeof (struct mach_o_section_32);
1063 }
1064 else
1065 {
1066 hdrsize = sizeof (struct mach_o_header_64);
1067 seghdrsize = sizeof (struct mach_o_segment_command_64);
1068 sechdrsize = sizeof (struct mach_o_section_64);
1069 }
1070
1071 name_offset = 0;
1072 *nsects = nsects_in = 0;
1073
1074 /* Count the number of sections we start with. */
1075
1076 for (section = sobj->sections; section != NULL; section = section->next)
1077 nsects_in++;
1078
1079 if (sobj->segment_name != NULL)
1080 {
1081 /* We will only write 3 sections: wrapped data, index and names. */
1082
1083 *nsects = 3;
1084
1085 /* The index has four entries per wrapped section:
1086 Section Offset, length, Name offset, length.
1087 Where the offsets are based at the start of the wrapper and name
1088 sections respectively.
1089 The values are stored as 32 bit int for both 32 and 64 bit mach-o
1090 since the size of a mach-o MH_OBJECT cannot exceed 4G owing to
1091 other constraints. */
1092
1093 index = XNEWVEC (unsigned int, nsects_in * 4);
1094
1095 /* We now need to figure out the size of the names section. This just
1096 stores the names as null-terminated c strings, packed without any
1097 alignment padding. */
1098
1099 for (section = sobj->sections, sect = 0; section != NULL;
1100 section = section->next, sect++)
1101 {
1102 index[sect*4+2] = name_offset;
1103 index[sect*4+3] = strlen (section->name) + 1;
1104 name_offset += strlen (section->name) + 1;
1105 }
1106 snames = XNEWVEC (char, name_offset);
1107 }
1108 else
1109 {
1110 *nsects = nsects_in;
1111 index = NULL;
1112 snames = NULL;
1113 }
1114
1115 sechdr_offset = hdrsize + seghdrsize;
1116 cmdsize = seghdrsize + *nsects * sechdrsize;
1117 offset = hdrsize + cmdsize;
1118 secaddr = 0;
1119
1120 for (section = sobj->sections, sect = 0;
1121 section != NULL; section = section->next, sect++)
1122 {
1123 size_t mask;
1124 size_t new_offset;
1125 size_t secsize;
1126 struct simple_object_write_section_buffer *buffer;
1127
1128 mask = (1U << section->align) - 1;
1129 new_offset = offset + mask;
1130 new_offset &= ~ mask;
1131 while (new_offset > offset)
1132 {
1133 unsigned char zeroes[16];
1134 size_t write;
1135
1136 memset (zeroes, 0, sizeof zeroes);
1137 write = new_offset - offset;
1138 if (write > sizeof zeroes)
1139 write = sizeof zeroes;
1140 if (!simple_object_internal_write (descriptor, offset, zeroes, write,
1141 errmsg, err))
1142 return 0;
1143 offset += write;
1144 }
1145
1146 secsize = 0;
1147 for (buffer = section->buffers; buffer != NULL; buffer = buffer->next)
1148 {
1149 if (!simple_object_internal_write (descriptor, offset + secsize,
1150 ((const unsigned char *)
1151 buffer->buffer),
1152 buffer->size, errmsg, err))
1153 return 0;
1154 secsize += buffer->size;
1155 }
1156
1157 if (sobj->segment_name != NULL)
1158 {
1159 index[sect*4+0] = (unsigned int) offset;
1160 index[sect*4+1] = secsize;
1161 /* Stash the section name in our table. */
1162 memcpy (snames + index[sect * 4 + 2], section->name,
1163 index[sect * 4 + 3]);
1164 }
1165 else
1166 {
1167 char namebuf[MACH_O_NAME_LEN + 1];
1168 char segnbuf[MACH_O_NAME_LEN + 1];
1169 char *comma;
1170
1171 /* Try to extract segment,section from the input name. */
1172
1173 memset (namebuf, 0, sizeof namebuf);
1174 memset (segnbuf, 0, sizeof segnbuf);
1175 comma = strchr (section->name, ',');
1176 if (comma != NULL)
1177 {
1178 int len = comma - section->name;
1179 len = len > MACH_O_NAME_LEN ? MACH_O_NAME_LEN : len;
1180 strncpy (namebuf, section->name, len);
1181 strncpy (segnbuf, comma + 1, MACH_O_NAME_LEN);
1182 }
1183 else /* just try to copy the name, leave segment blank. */
1184 strncpy (namebuf, section->name, MACH_O_NAME_LEN);
1185
1186 if (!simple_object_mach_o_write_section_header (sobj, descriptor,
1187 sechdr_offset,
1188 namebuf, segnbuf,
1189 secaddr, secsize,
1190 offset,
1191 section->align,
1192 errmsg, err))
1193 return 0;
1194 sechdr_offset += sechdrsize;
1195 }
1196
1197 offset += secsize;
1198 secaddr += secsize;
1199 }
1200
1201 if (sobj->segment_name != NULL)
1202 {
1203 size_t secsize;
1204 unsigned int i;
1205
1206 /* Write the section header for the wrapper. */
1207 /* Account for any initial aligment - which becomes the alignment for this
1208 created section. */
1209
1210 secsize = (offset - index[0]);
1211 if (!simple_object_mach_o_write_section_header (sobj, descriptor,
1212 sechdr_offset,
1213 GNU_WRAPPER_SECTS,
1214 sobj->segment_name,
1215 0 /*secaddr*/,
1216 secsize, index[0],
1217 sobj->sections->align,
1218 errmsg, err))
1219 return 0;
1220
1221 /* Subtract the wrapper section start from the begining of each sub
1222 section. */
1223
1224 for (i = 1; i < nsects_in; ++i)
1225 index[4 * i] -= index[0];
1226 index[0] = 0;
1227
1228 /* Swap the indices, if required. */
1229
1230 for (i = 0; i < (nsects_in * 4); ++i)
1231 set_32 ((unsigned char *) &index[i], index[i]);
1232
1233 sechdr_offset += sechdrsize;
1234
1235 /* Write out the section names.
1236 ... the header ...
1237 name_offset contains the length of the section. It is not aligned. */
1238
1239 if (!simple_object_mach_o_write_section_header (sobj, descriptor,
1240 sechdr_offset,
1241 GNU_WRAPPER_NAMES,
1242 sobj->segment_name,
1243 0 /*secaddr*/,
1244 name_offset,
1245 offset,
1246 0, errmsg, err))
1247 return 0;
1248
1249 /* ... and the content.. */
1250 if (!simple_object_internal_write (descriptor, offset,
1251 (const unsigned char *) snames,
1252 name_offset, errmsg, err))
1253 return 0;
1254
1255 sechdr_offset += sechdrsize;
1256 secaddr += name_offset;
1257 offset += name_offset;
1258
1259 /* Now do the index, we'll align this to 4 bytes although the read code
1260 will handle unaligned. */
1261
1262 offset += 3;
1263 offset &= ~0x03;
1264 if (!simple_object_mach_o_write_section_header (sobj, descriptor,
1265 sechdr_offset,
1266 GNU_WRAPPER_INDEX,
1267 sobj->segment_name,
1268 0 /*secaddr*/,
1269 nsects_in * 16,
1270 offset,
1271 2, errmsg, err))
1272 return 0;
1273
1274 /* ... and the content.. */
1275 if (!simple_object_internal_write (descriptor, offset,
1276 (const unsigned char *) index,
1277 nsects_in*16, errmsg, err))
1278 return 0;
1279
1280 XDELETEVEC (index);
1281 XDELETEVEC (snames);
1282 }
1283
1284 /* Write out the segment header. */
1285
1286 memset (hdrbuf, 0, sizeof hdrbuf);
1287
1288 hdr = &hdrbuf[0];
1289 if (attrs->magic == MACH_O_MH_MAGIC)
1290 {
1291 set_32 (hdr + offsetof (struct mach_o_segment_command_32, cmd),
1292 MACH_O_LC_SEGMENT);
1293 set_32 (hdr + offsetof (struct mach_o_segment_command_32, cmdsize),
1294 cmdsize);
1295 /* MH_OBJECTS have a single, anonymous, segment - so the segment name
1296 is left empty. */
1297 /* vmaddr left as zero. */
1298 /* vmsize left as zero. */
1299 set_32 (hdr + offsetof (struct mach_o_segment_command_32, fileoff),
1300 hdrsize + cmdsize);
1301 set_32 (hdr + offsetof (struct mach_o_segment_command_32, filesize),
1302 offset - (hdrsize + cmdsize));
1303 /* maxprot left as zero. */
1304 /* initprot left as zero. */
1305 set_32 (hdr + offsetof (struct mach_o_segment_command_32, nsects),
1306 *nsects);
1307 /* flags left as zero. */
1308 }
1309 else
1310 {
1311 #ifdef UNSIGNED_64BIT_TYPE
1312 void (*set_64) (unsigned char *, ulong_type);
1313
1314 set_64 = (attrs->is_big_endian
1315 ? simple_object_set_big_64
1316 : simple_object_set_little_64);
1317
1318 set_32 (hdr + offsetof (struct mach_o_segment_command_64, cmd),
1319 MACH_O_LC_SEGMENT);
1320 set_32 (hdr + offsetof (struct mach_o_segment_command_64, cmdsize),
1321 cmdsize);
1322 /* MH_OBJECTS have a single, anonymous, segment - so the segment name
1323 is left empty. */
1324 /* vmaddr left as zero. */
1325 /* vmsize left as zero. */
1326 set_64 (hdr + offsetof (struct mach_o_segment_command_64, fileoff),
1327 hdrsize + cmdsize);
1328 set_64 (hdr + offsetof (struct mach_o_segment_command_64, filesize),
1329 offset - (hdrsize + cmdsize));
1330 /* maxprot left as zero. */
1331 /* initprot left as zero. */
1332 set_32 (hdr + offsetof (struct mach_o_segment_command_64, nsects),
1333 *nsects);
1334 /* flags left as zero. */
1335 #endif
1336 }
1337
1338 return simple_object_internal_write (descriptor, hdrsize, hdr, seghdrsize,
1339 errmsg, err);
1340 }
1341
1342 /* Write out a complete Mach-O file. */
1343
1344 static const char *
simple_object_mach_o_write_to_file(simple_object_write * sobj,int descriptor,int * err)1345 simple_object_mach_o_write_to_file (simple_object_write *sobj, int descriptor,
1346 int *err)
1347 {
1348 size_t nsects = 0;
1349 const char *errmsg;
1350
1351 if (!simple_object_mach_o_write_segment (sobj, descriptor, &nsects,
1352 &errmsg, err))
1353 return errmsg;
1354
1355 if (!simple_object_mach_o_write_header (sobj, descriptor, nsects,
1356 &errmsg, err))
1357 return errmsg;
1358
1359 return NULL;
1360 }
1361
1362 /* Release the private data for an simple_object_write structure. */
1363
1364 static void
simple_object_mach_o_release_write(void * data)1365 simple_object_mach_o_release_write (void *data)
1366 {
1367 XDELETE (data);
1368 }
1369
1370 /* The Mach-O functions. */
1371
1372 const struct simple_object_functions simple_object_mach_o_functions =
1373 {
1374 simple_object_mach_o_match,
1375 simple_object_mach_o_find_sections,
1376 simple_object_mach_o_fetch_attributes,
1377 simple_object_mach_o_release_read,
1378 simple_object_mach_o_attributes_merge,
1379 simple_object_mach_o_release_attributes,
1380 simple_object_mach_o_start_write,
1381 simple_object_mach_o_write_to_file,
1382 simple_object_mach_o_release_write,
1383 NULL
1384 };
1385