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[emacs.git] / src / unexmacosx.c
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1 /* Dump Emacs in Mach-O format for use on Mac OS X.
2 Copyright (C) 2001-2013 Free Software Foundation, Inc.
4 This file is part of GNU Emacs.
6 GNU Emacs is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 GNU Emacs 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
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */
19 /* Contributed by Andrew Choi (akochoi@mac.com). */
21 /* Documentation note.
23 Consult the following documents/files for a description of the
24 Mach-O format: the file loader.h, man pages for Mach-O and ld, old
25 NEXTSTEP documents of the Mach-O format. The tool otool dumps the
26 mach header (-h option) and the load commands (-l option) in a
27 Mach-O file. The tool nm on Mac OS X displays the symbol table in
28 a Mach-O file. For examples of unexec for the Mach-O format, see
29 the file unexnext.c in the GNU Emacs distribution, the file
30 unexdyld.c in the Darwin port of GNU Emacs 20.7, and unexdyld.c in
31 the Darwin port of XEmacs 21.1. Also the Darwin Libc source
32 contains the source code for malloc_freezedry and malloc_jumpstart.
33 Read that to see what they do. This file was written completely
34 from scratch, making use of information from the above sources. */
36 /* The Mac OS X implementation of unexec makes use of Darwin's `zone'
37 memory allocator. All calls to malloc, realloc, and free in Emacs
38 are redirected to unexec_malloc, unexec_realloc, and unexec_free in
39 this file. When temacs is run, all memory requests are handled in
40 the zone EmacsZone. The Darwin memory allocator library calls
41 maintain the data structures to manage this zone. Dumping writes
42 its contents to data segments of the executable file. When emacs
43 is run, the loader recreates the contents of the zone in memory.
44 However since the initialization routine of the zone memory
45 allocator is run again, this `zone' can no longer be used as a
46 heap. That is why emacs uses the ordinary malloc system call to
47 allocate memory. Also, when a block of memory needs to be
48 reallocated and the new size is larger than the old one, a new
49 block must be obtained by malloc and the old contents copied to
50 it. */
52 /* Peculiarity of the Mach-O files generated by ld in Mac OS X
53 (possible causes of future bugs if changed).
55 The file offset of the start of the __TEXT segment is zero. Since
56 the Mach header and load commands are located at the beginning of a
57 Mach-O file, copying the contents of the __TEXT segment from the
58 input file overwrites them in the output file. Despite this,
59 unexec works fine as written below because the segment load command
60 for __TEXT appears, and is therefore processed, before all other
61 load commands except the segment load command for __PAGEZERO, which
62 remains unchanged.
64 Although the file offset of the start of the __TEXT segment is
65 zero, none of the sections it contains actually start there. In
66 fact, the earliest one starts a few hundred bytes beyond the end of
67 the last load command. The linker option -headerpad controls the
68 minimum size of this padding. Its setting can be changed in
69 s/darwin.h. A value of 0x690, e.g., leaves room for 30 additional
70 load commands for the newly created __DATA segments (at 56 bytes
71 each). Unexec fails if there is not enough room for these new
72 segments.
74 The __TEXT segment contains the sections __text, __cstring,
75 __picsymbol_stub, and __const and the __DATA segment contains the
76 sections __data, __la_symbol_ptr, __nl_symbol_ptr, __dyld, __bss,
77 and __common. The other segments do not contain any sections.
78 These sections are copied from the input file to the output file,
79 except for __data, __bss, and __common, which are dumped from
80 memory. The types of the sections __bss and __common are changed
81 from S_ZEROFILL to S_REGULAR. Note that the number of sections and
82 their relative order in the input and output files remain
83 unchanged. Otherwise all n_sect fields in the nlist records in the
84 symbol table (specified by the LC_SYMTAB load command) will have to
85 be changed accordingly.
88 /* config.h #define:s malloc/realloc/free and then includes stdlib.h.
89 We want the undefined versions, but if config.h includes stdlib.h
90 with the #define:s in place, the prototypes will be wrong and we get
91 warnings. To prevent that, include stdlib.h before config.h. */
93 #include <stdlib.h>
94 #include <config.h>
95 #undef malloc
96 #undef realloc
97 #undef free
99 #include "unexec.h"
101 #include <stdio.h>
102 #include <fcntl.h>
103 #include <stdarg.h>
104 #include <sys/types.h>
105 #include <unistd.h>
106 #include <mach/mach.h>
107 #include <mach-o/loader.h>
108 #include <mach-o/reloc.h>
109 #if defined (__ppc__)
110 #include <mach-o/ppc/reloc.h>
111 #endif
112 #ifdef HAVE_MALLOC_MALLOC_H
113 #include <malloc/malloc.h>
114 #else
115 #include <objc/malloc.h>
116 #endif
118 #include <assert.h>
120 /* LC_DATA_IN_CODE is not defined in mach-o/loader.h on OS X 10.7.
121 But it is used if we build with "Command Line Tools for Xcode 4.5
122 (OS X Lion) - September 2012". */
123 #ifndef LC_DATA_IN_CODE
124 #define LC_DATA_IN_CODE 0x29 /* table of non-instructions in __text */
125 #endif
127 #ifdef _LP64
128 #define mach_header mach_header_64
129 #define segment_command segment_command_64
130 #undef VM_REGION_BASIC_INFO_COUNT
131 #define VM_REGION_BASIC_INFO_COUNT VM_REGION_BASIC_INFO_COUNT_64
132 #undef VM_REGION_BASIC_INFO
133 #define VM_REGION_BASIC_INFO VM_REGION_BASIC_INFO_64
134 #undef LC_SEGMENT
135 #define LC_SEGMENT LC_SEGMENT_64
136 #define vm_region vm_region_64
137 #define section section_64
138 #undef MH_MAGIC
139 #define MH_MAGIC MH_MAGIC_64
140 #endif
142 #define VERBOSE 1
144 /* Size of buffer used to copy data from the input file to the output
145 file in function unexec_copy. */
146 #define UNEXEC_COPY_BUFSZ 1024
148 /* Regions with memory addresses above this value are assumed to be
149 mapped to dynamically loaded libraries and will not be dumped. */
150 #define VM_DATA_TOP (20 * 1024 * 1024)
152 /* Type of an element on the list of regions to be dumped. */
153 struct region_t {
154 vm_address_t address;
155 vm_size_t size;
156 vm_prot_t protection;
157 vm_prot_t max_protection;
159 struct region_t *next;
162 /* Head and tail of the list of regions to be dumped. */
163 static struct region_t *region_list_head = 0;
164 static struct region_t *region_list_tail = 0;
166 /* Pointer to array of load commands. */
167 static struct load_command **lca;
169 /* Number of load commands. */
170 static int nlc;
172 /* The highest VM address of segments loaded by the input file.
173 Regions with addresses beyond this are assumed to be allocated
174 dynamically and thus require dumping. */
175 static vm_address_t infile_lc_highest_addr = 0;
177 /* The lowest file offset used by the all sections in the __TEXT
178 segments. This leaves room at the beginning of the file to store
179 the Mach-O header. Check this value against header size to ensure
180 the added load commands for the new __DATA segments did not
181 overwrite any of the sections in the __TEXT segment. */
182 static unsigned long text_seg_lowest_offset = 0x10000000;
184 /* Mach header. */
185 static struct mach_header mh;
187 /* Offset at which the next load command should be written. */
188 static unsigned long curr_header_offset = sizeof (struct mach_header);
190 /* Offset at which the next segment should be written. */
191 static unsigned long curr_file_offset = 0;
193 static unsigned long pagesize;
194 #define ROUNDUP_TO_PAGE_BOUNDARY(x) (((x) + pagesize - 1) & ~(pagesize - 1))
196 static int infd, outfd;
198 static int in_dumped_exec = 0;
200 static malloc_zone_t *emacs_zone;
202 /* file offset of input file's data segment */
203 static off_t data_segment_old_fileoff = 0;
205 static struct segment_command *data_segment_scp;
207 /* Read N bytes from infd into memory starting at address DEST.
208 Return true if successful, false otherwise. */
209 static int
210 unexec_read (void *dest, size_t n)
212 return n == read (infd, dest, n);
215 /* Write COUNT bytes from memory starting at address SRC to outfd
216 starting at offset DEST. Return true if successful, false
217 otherwise. */
218 static int
219 unexec_write (off_t dest, const void *src, size_t count)
221 if (lseek (outfd, dest, SEEK_SET) != dest)
222 return 0;
224 return write (outfd, src, count) == count;
227 /* Write COUNT bytes of zeros to outfd starting at offset DEST.
228 Return true if successful, false otherwise. */
229 static int
230 unexec_write_zero (off_t dest, size_t count)
232 char buf[UNEXEC_COPY_BUFSZ];
233 ssize_t bytes;
235 memset (buf, 0, UNEXEC_COPY_BUFSZ);
236 if (lseek (outfd, dest, SEEK_SET) != dest)
237 return 0;
239 while (count > 0)
241 bytes = count > UNEXEC_COPY_BUFSZ ? UNEXEC_COPY_BUFSZ : count;
242 if (write (outfd, buf, bytes) != bytes)
243 return 0;
244 count -= bytes;
247 return 1;
250 /* Copy COUNT bytes from starting offset SRC in infd to starting
251 offset DEST in outfd. Return true if successful, false
252 otherwise. */
253 static int
254 unexec_copy (off_t dest, off_t src, ssize_t count)
256 ssize_t bytes_read;
257 ssize_t bytes_to_read;
259 char buf[UNEXEC_COPY_BUFSZ];
261 if (lseek (infd, src, SEEK_SET) != src)
262 return 0;
264 if (lseek (outfd, dest, SEEK_SET) != dest)
265 return 0;
267 while (count > 0)
269 bytes_to_read = count > UNEXEC_COPY_BUFSZ ? UNEXEC_COPY_BUFSZ : count;
270 bytes_read = read (infd, buf, bytes_to_read);
271 if (bytes_read <= 0)
272 return 0;
273 if (write (outfd, buf, bytes_read) != bytes_read)
274 return 0;
275 count -= bytes_read;
278 return 1;
281 /* Debugging and informational messages routines. */
283 static _Noreturn void
284 unexec_error (const char *format, ...)
286 va_list ap;
288 va_start (ap, format);
289 fprintf (stderr, "unexec: ");
290 vfprintf (stderr, format, ap);
291 fprintf (stderr, "\n");
292 va_end (ap);
293 exit (1);
296 static void
297 print_prot (vm_prot_t prot)
299 if (prot == VM_PROT_NONE)
300 printf ("none");
301 else
303 putchar (prot & VM_PROT_READ ? 'r' : ' ');
304 putchar (prot & VM_PROT_WRITE ? 'w' : ' ');
305 putchar (prot & VM_PROT_EXECUTE ? 'x' : ' ');
306 putchar (' ');
310 static void
311 print_region (vm_address_t address, vm_size_t size, vm_prot_t prot,
312 vm_prot_t max_prot)
314 printf ("%#10lx %#8lx ", (long) address, (long) size);
315 print_prot (prot);
316 putchar (' ');
317 print_prot (max_prot);
318 putchar ('\n');
321 static void
322 print_region_list (void)
324 struct region_t *r;
326 printf (" address size prot maxp\n");
328 for (r = region_list_head; r; r = r->next)
329 print_region (r->address, r->size, r->protection, r->max_protection);
332 static void
333 print_regions (void)
335 task_t target_task = mach_task_self ();
336 vm_address_t address = (vm_address_t) 0;
337 vm_size_t size;
338 struct vm_region_basic_info info;
339 mach_msg_type_number_t info_count = VM_REGION_BASIC_INFO_COUNT;
340 mach_port_t object_name;
342 printf (" address size prot maxp\n");
344 while (vm_region (target_task, &address, &size, VM_REGION_BASIC_INFO,
345 (vm_region_info_t) &info, &info_count, &object_name)
346 == KERN_SUCCESS && info_count == VM_REGION_BASIC_INFO_COUNT)
348 print_region (address, size, info.protection, info.max_protection);
350 if (object_name != MACH_PORT_NULL)
351 mach_port_deallocate (target_task, object_name);
353 address += size;
357 /* Build the list of regions that need to be dumped. Regions with
358 addresses above VM_DATA_TOP are omitted. Adjacent regions with
359 identical protection are merged. Note that non-writable regions
360 cannot be omitted because they some regions created at run time are
361 read-only. */
362 static void
363 build_region_list (void)
365 task_t target_task = mach_task_self ();
366 vm_address_t address = (vm_address_t) 0;
367 vm_size_t size;
368 struct vm_region_basic_info info;
369 mach_msg_type_number_t info_count = VM_REGION_BASIC_INFO_COUNT;
370 mach_port_t object_name;
371 struct region_t *r;
373 #if VERBOSE
374 printf ("--- List of All Regions ---\n");
375 printf (" address size prot maxp\n");
376 #endif
378 while (vm_region (target_task, &address, &size, VM_REGION_BASIC_INFO,
379 (vm_region_info_t) &info, &info_count, &object_name)
380 == KERN_SUCCESS && info_count == VM_REGION_BASIC_INFO_COUNT)
382 /* Done when we reach addresses of shared libraries, which are
383 loaded in high memory. */
384 if (address >= VM_DATA_TOP)
385 break;
387 #if VERBOSE
388 print_region (address, size, info.protection, info.max_protection);
389 #endif
391 /* If a region immediately follows the previous one (the one
392 most recently added to the list) and has identical
393 protection, merge it with the latter. Otherwise create a
394 new list element for it. */
395 if (region_list_tail
396 && info.protection == region_list_tail->protection
397 && info.max_protection == region_list_tail->max_protection
398 && region_list_tail->address + region_list_tail->size == address)
400 region_list_tail->size += size;
402 else
404 r = malloc (sizeof *r);
406 if (!r)
407 unexec_error ("cannot allocate region structure");
409 r->address = address;
410 r->size = size;
411 r->protection = info.protection;
412 r->max_protection = info.max_protection;
414 r->next = 0;
415 if (region_list_head == 0)
417 region_list_head = r;
418 region_list_tail = r;
420 else
422 region_list_tail->next = r;
423 region_list_tail = r;
426 /* Deallocate (unused) object name returned by
427 vm_region. */
428 if (object_name != MACH_PORT_NULL)
429 mach_port_deallocate (target_task, object_name);
432 address += size;
435 printf ("--- List of Regions to be Dumped ---\n");
436 print_region_list ();
440 #define MAX_UNEXEC_REGIONS 400
442 static int num_unexec_regions;
443 typedef struct {
444 vm_range_t range;
445 vm_size_t filesize;
446 } unexec_region_info;
447 static unexec_region_info unexec_regions[MAX_UNEXEC_REGIONS];
449 static void
450 unexec_regions_recorder (task_t task, void *rr, unsigned type,
451 vm_range_t *ranges, unsigned num)
453 vm_address_t p;
454 vm_size_t filesize;
456 while (num && num_unexec_regions < MAX_UNEXEC_REGIONS)
458 /* Subtract the size of trailing null bytes from filesize. It
459 can be smaller than vmsize in segment commands. In such a
460 case, trailing bytes are initialized with zeros. */
461 for (p = ranges->address + ranges->size; p > ranges->address; p--)
462 if (*(((char *) p)-1))
463 break;
464 filesize = p - ranges->address;
466 unexec_regions[num_unexec_regions].filesize = filesize;
467 unexec_regions[num_unexec_regions++].range = *ranges;
468 printf ("%#10lx (sz: %#8lx/%#8lx)\n", (long) (ranges->address),
469 (long) filesize, (long) (ranges->size));
470 ranges++; num--;
474 static kern_return_t
475 unexec_reader (task_t task, vm_address_t address, vm_size_t size, void **ptr)
477 *ptr = (void *) address;
478 return KERN_SUCCESS;
481 static void
482 find_emacs_zone_regions (void)
484 num_unexec_regions = 0;
486 emacs_zone->introspect->enumerator (mach_task_self (), 0,
487 MALLOC_PTR_REGION_RANGE_TYPE
488 | MALLOC_ADMIN_REGION_RANGE_TYPE,
489 (vm_address_t) emacs_zone,
490 unexec_reader,
491 unexec_regions_recorder);
493 if (num_unexec_regions == MAX_UNEXEC_REGIONS)
494 unexec_error ("find_emacs_zone_regions: too many regions");
497 static int
498 unexec_regions_sort_compare (const void *a, const void *b)
500 vm_address_t aa = ((unexec_region_info *) a)->range.address;
501 vm_address_t bb = ((unexec_region_info *) b)->range.address;
503 if (aa < bb)
504 return -1;
505 else if (aa > bb)
506 return 1;
507 else
508 return 0;
511 static void
512 unexec_regions_merge (void)
514 int i, n;
515 unexec_region_info r;
516 vm_size_t padsize;
518 qsort (unexec_regions, num_unexec_regions, sizeof (unexec_regions[0]),
519 &unexec_regions_sort_compare);
520 n = 0;
521 r = unexec_regions[0];
522 padsize = r.range.address & (pagesize - 1);
523 if (padsize)
525 r.range.address -= padsize;
526 r.range.size += padsize;
527 r.filesize += padsize;
529 for (i = 1; i < num_unexec_regions; i++)
531 if (r.range.address + r.range.size == unexec_regions[i].range.address
532 && r.range.size - r.filesize < 2 * pagesize)
534 r.filesize = r.range.size + unexec_regions[i].filesize;
535 r.range.size += unexec_regions[i].range.size;
537 else
539 unexec_regions[n++] = r;
540 r = unexec_regions[i];
541 padsize = r.range.address & (pagesize - 1);
542 if (padsize)
544 if ((unexec_regions[n-1].range.address
545 + unexec_regions[n-1].range.size) == r.range.address)
546 unexec_regions[n-1].range.size -= padsize;
548 r.range.address -= padsize;
549 r.range.size += padsize;
550 r.filesize += padsize;
554 unexec_regions[n++] = r;
555 num_unexec_regions = n;
559 /* More informational messages routines. */
561 static void
562 print_load_command_name (int lc)
564 switch (lc)
566 case LC_SEGMENT:
567 #ifndef _LP64
568 printf ("LC_SEGMENT ");
569 #else
570 printf ("LC_SEGMENT_64 ");
571 #endif
572 break;
573 case LC_LOAD_DYLINKER:
574 printf ("LC_LOAD_DYLINKER ");
575 break;
576 case LC_LOAD_DYLIB:
577 printf ("LC_LOAD_DYLIB ");
578 break;
579 case LC_SYMTAB:
580 printf ("LC_SYMTAB ");
581 break;
582 case LC_DYSYMTAB:
583 printf ("LC_DYSYMTAB ");
584 break;
585 case LC_UNIXTHREAD:
586 printf ("LC_UNIXTHREAD ");
587 break;
588 case LC_PREBOUND_DYLIB:
589 printf ("LC_PREBOUND_DYLIB");
590 break;
591 case LC_TWOLEVEL_HINTS:
592 printf ("LC_TWOLEVEL_HINTS");
593 break;
594 #ifdef LC_UUID
595 case LC_UUID:
596 printf ("LC_UUID ");
597 break;
598 #endif
599 #ifdef LC_DYLD_INFO
600 case LC_DYLD_INFO:
601 printf ("LC_DYLD_INFO ");
602 break;
603 case LC_DYLD_INFO_ONLY:
604 printf ("LC_DYLD_INFO_ONLY");
605 break;
606 #endif
607 #ifdef LC_VERSION_MIN_MACOSX
608 case LC_VERSION_MIN_MACOSX:
609 printf ("LC_VERSION_MIN_MACOSX");
610 break;
611 #endif
612 #ifdef LC_FUNCTION_STARTS
613 case LC_FUNCTION_STARTS:
614 printf ("LC_FUNCTION_STARTS");
615 break;
616 #endif
617 #ifdef LC_MAIN
618 case LC_MAIN:
619 printf ("LC_MAIN ");
620 break;
621 #endif
622 #ifdef LC_DATA_IN_CODE
623 case LC_DATA_IN_CODE:
624 printf ("LC_DATA_IN_CODE ");
625 break;
626 #endif
627 #ifdef LC_SOURCE_VERSION
628 case LC_SOURCE_VERSION:
629 printf ("LC_SOURCE_VERSION");
630 break;
631 #endif
632 #ifdef LC_DYLIB_CODE_SIGN_DRS
633 case LC_DYLIB_CODE_SIGN_DRS:
634 printf ("LC_DYLIB_CODE_SIGN_DRS");
635 break;
636 #endif
637 default:
638 printf ("unknown ");
642 static void
643 print_load_command (struct load_command *lc)
645 print_load_command_name (lc->cmd);
646 printf ("%8d", lc->cmdsize);
648 if (lc->cmd == LC_SEGMENT)
650 struct segment_command *scp;
651 struct section *sectp;
652 int j;
654 scp = (struct segment_command *) lc;
655 printf (" %-16.16s %#10lx %#8lx\n",
656 scp->segname, (long) (scp->vmaddr), (long) (scp->vmsize));
658 sectp = (struct section *) (scp + 1);
659 for (j = 0; j < scp->nsects; j++)
661 printf (" %-16.16s %#10lx %#8lx\n",
662 sectp->sectname, (long) (sectp->addr), (long) (sectp->size));
663 sectp++;
666 else
667 printf ("\n");
670 /* Read header and load commands from input file. Store the latter in
671 the global array lca. Store the total number of load commands in
672 global variable nlc. */
673 static void
674 read_load_commands (void)
676 int i;
678 if (!unexec_read (&mh, sizeof (struct mach_header)))
679 unexec_error ("cannot read mach-o header");
681 if (mh.magic != MH_MAGIC)
682 unexec_error ("input file not in Mach-O format");
684 if (mh.filetype != MH_EXECUTE)
685 unexec_error ("input Mach-O file is not an executable object file");
687 #if VERBOSE
688 printf ("--- Header Information ---\n");
689 printf ("Magic = 0x%08x\n", mh.magic);
690 printf ("CPUType = %d\n", mh.cputype);
691 printf ("CPUSubType = %d\n", mh.cpusubtype);
692 printf ("FileType = 0x%x\n", mh.filetype);
693 printf ("NCmds = %d\n", mh.ncmds);
694 printf ("SizeOfCmds = %d\n", mh.sizeofcmds);
695 printf ("Flags = 0x%08x\n", mh.flags);
696 #endif
698 nlc = mh.ncmds;
699 lca = malloc (nlc * sizeof *lca);
701 for (i = 0; i < nlc; i++)
703 struct load_command lc;
704 /* Load commands are variable-size: so read the command type and
705 size first and then read the rest. */
706 if (!unexec_read (&lc, sizeof (struct load_command)))
707 unexec_error ("cannot read load command");
708 lca[i] = malloc (lc.cmdsize);
709 memcpy (lca[i], &lc, sizeof (struct load_command));
710 if (!unexec_read (lca[i] + 1, lc.cmdsize - sizeof (struct load_command)))
711 unexec_error ("cannot read content of load command");
712 if (lc.cmd == LC_SEGMENT)
714 struct segment_command *scp = (struct segment_command *) lca[i];
716 if (scp->vmaddr + scp->vmsize > infile_lc_highest_addr)
717 infile_lc_highest_addr = scp->vmaddr + scp->vmsize;
719 if (strncmp (scp->segname, SEG_TEXT, 16) == 0)
721 struct section *sectp = (struct section *) (scp + 1);
722 int j;
724 for (j = 0; j < scp->nsects; j++)
725 if (sectp->offset < text_seg_lowest_offset)
726 text_seg_lowest_offset = sectp->offset;
731 printf ("Highest address of load commands in input file: %#8lx\n",
732 (unsigned long)infile_lc_highest_addr);
734 printf ("Lowest offset of all sections in __TEXT segment: %#8lx\n",
735 text_seg_lowest_offset);
737 printf ("--- List of Load Commands in Input File ---\n");
738 printf ("# cmd cmdsize name address size\n");
740 for (i = 0; i < nlc; i++)
742 printf ("%1d ", i);
743 print_load_command (lca[i]);
747 /* Copy a LC_SEGMENT load command other than the __DATA segment from
748 the input file to the output file, adjusting the file offset of the
749 segment and the file offsets of sections contained in it. */
750 static void
751 copy_segment (struct load_command *lc)
753 struct segment_command *scp = (struct segment_command *) lc;
754 unsigned long old_fileoff = scp->fileoff;
755 struct section *sectp;
756 int j;
758 scp->fileoff = curr_file_offset;
760 sectp = (struct section *) (scp + 1);
761 for (j = 0; j < scp->nsects; j++)
763 sectp->offset += curr_file_offset - old_fileoff;
764 sectp++;
767 printf ("Writing segment %-16.16s @ %#8lx (%#8lx/%#8lx @ %#10lx)\n",
768 scp->segname, (long) (scp->fileoff), (long) (scp->filesize),
769 (long) (scp->vmsize), (long) (scp->vmaddr));
771 if (!unexec_copy (scp->fileoff, old_fileoff, scp->filesize))
772 unexec_error ("cannot copy segment from input to output file");
773 curr_file_offset += ROUNDUP_TO_PAGE_BOUNDARY (scp->filesize);
775 if (!unexec_write (curr_header_offset, lc, lc->cmdsize))
776 unexec_error ("cannot write load command to header");
778 curr_header_offset += lc->cmdsize;
781 /* Copy a LC_SEGMENT load command for the __DATA segment in the input
782 file to the output file. We assume that only one such segment load
783 command exists in the input file and it contains the sections
784 __data, __bss, __common, __la_symbol_ptr, __nl_symbol_ptr, and
785 __dyld. The first three of these should be dumped from memory and
786 the rest should be copied from the input file. Note that the
787 sections __bss and __common contain no data in the input file
788 because their flag fields have the value S_ZEROFILL. Dumping these
789 from memory makes it necessary to adjust file offset fields in
790 subsequently dumped load commands. Then, create new __DATA segment
791 load commands for regions on the region list other than the one
792 corresponding to the __DATA segment in the input file. */
793 static void
794 copy_data_segment (struct load_command *lc)
796 struct segment_command *scp = (struct segment_command *) lc;
797 struct section *sectp;
798 int j;
799 unsigned long header_offset, old_file_offset;
801 /* The new filesize of the segment is set to its vmsize because data
802 blocks for segments must start at region boundaries. Note that
803 this may leave unused locations at the end of the segment data
804 block because the total of the sizes of all sections in the
805 segment is generally smaller than vmsize. */
806 scp->filesize = scp->vmsize;
808 printf ("Writing segment %-16.16s @ %#8lx (%#8lx/%#8lx @ %#10lx)\n",
809 scp->segname, curr_file_offset, (long)(scp->filesize),
810 (long)(scp->vmsize), (long) (scp->vmaddr));
812 /* Offsets in the output file for writing the next section structure
813 and segment data block, respectively. */
814 header_offset = curr_header_offset + sizeof (struct segment_command);
816 sectp = (struct section *) (scp + 1);
817 for (j = 0; j < scp->nsects; j++)
819 old_file_offset = sectp->offset;
820 sectp->offset = sectp->addr - scp->vmaddr + curr_file_offset;
821 /* The __data section is dumped from memory. The __bss and
822 __common sections are also dumped from memory but their flag
823 fields require changing (from S_ZEROFILL to S_REGULAR). The
824 other three kinds of sections are just copied from the input
825 file. */
826 if (strncmp (sectp->sectname, SECT_DATA, 16) == 0)
828 extern char my_edata[];
829 unsigned long my_size;
831 /* The __data section is basically dumped from memory. But
832 initialized data in statically linked libraries are
833 copied from the input file. In particular,
834 add_image_hook.names and add_image_hook.pointers stored
835 by libarclite_macosx.a, are restored so that they will be
836 reinitialized when the dumped binary is executed. */
837 my_size = (unsigned long)my_edata - sectp->addr;
838 if (!(sectp->addr <= (unsigned long)my_edata
839 && my_size <= sectp->size))
840 unexec_error ("my_edata is not in section %s", SECT_DATA);
841 if (!unexec_write (sectp->offset, (void *) sectp->addr, my_size))
842 unexec_error ("cannot write section %s", SECT_DATA);
843 if (!unexec_copy (sectp->offset + my_size, old_file_offset + my_size,
844 sectp->size - my_size))
845 unexec_error ("cannot copy section %s", SECT_DATA);
846 if (!unexec_write (header_offset, sectp, sizeof (struct section)))
847 unexec_error ("cannot write section %s's header", SECT_DATA);
849 else if (strncmp (sectp->sectname, SECT_COMMON, 16) == 0)
851 sectp->flags = S_REGULAR;
852 if (!unexec_write (sectp->offset, (void *) sectp->addr, sectp->size))
853 unexec_error ("cannot write section %.16s", sectp->sectname);
854 if (!unexec_write (header_offset, sectp, sizeof (struct section)))
855 unexec_error ("cannot write section %.16s's header", sectp->sectname);
857 else if (strncmp (sectp->sectname, SECT_BSS, 16) == 0)
859 extern char *my_endbss_static;
860 unsigned long my_size;
862 sectp->flags = S_REGULAR;
864 /* Clear uninitialized local variables in statically linked
865 libraries. In particular, function pointers stored by
866 libSystemStub.a, which is introduced in Mac OS X 10.4 for
867 binary compatibility with respect to long double, are
868 cleared so that they will be reinitialized when the
869 dumped binary is executed on other versions of OS. */
870 my_size = (unsigned long)my_endbss_static - sectp->addr;
871 if (!(sectp->addr <= (unsigned long)my_endbss_static
872 && my_size <= sectp->size))
873 unexec_error ("my_endbss_static is not in section %.16s",
874 sectp->sectname);
875 if (!unexec_write (sectp->offset, (void *) sectp->addr, my_size))
876 unexec_error ("cannot write section %.16s", sectp->sectname);
877 if (!unexec_write_zero (sectp->offset + my_size,
878 sectp->size - my_size))
879 unexec_error ("cannot write section %.16s", sectp->sectname);
880 if (!unexec_write (header_offset, sectp, sizeof (struct section)))
881 unexec_error ("cannot write section %.16s's header", sectp->sectname);
883 else if (strncmp (sectp->sectname, "__la_symbol_ptr", 16) == 0
884 || strncmp (sectp->sectname, "__nl_symbol_ptr", 16) == 0
885 || strncmp (sectp->sectname, "__got", 16) == 0
886 || strncmp (sectp->sectname, "__la_sym_ptr2", 16) == 0
887 || strncmp (sectp->sectname, "__dyld", 16) == 0
888 || strncmp (sectp->sectname, "__const", 16) == 0
889 || strncmp (sectp->sectname, "__cfstring", 16) == 0
890 || strncmp (sectp->sectname, "__gcc_except_tab", 16) == 0
891 || strncmp (sectp->sectname, "__program_vars", 16) == 0
892 || strncmp (sectp->sectname, "__mod_init_func", 16) == 0
893 || strncmp (sectp->sectname, "__mod_term_func", 16) == 0
894 || strncmp (sectp->sectname, "__objc_", 7) == 0)
896 if (!unexec_copy (sectp->offset, old_file_offset, sectp->size))
897 unexec_error ("cannot copy section %.16s", sectp->sectname);
898 if (!unexec_write (header_offset, sectp, sizeof (struct section)))
899 unexec_error ("cannot write section %.16s's header", sectp->sectname);
901 else
902 unexec_error ("unrecognized section %.16s in __DATA segment",
903 sectp->sectname);
905 printf (" section %-16.16s at %#8lx - %#8lx (sz: %#8lx)\n",
906 sectp->sectname, (long) (sectp->offset),
907 (long) (sectp->offset + sectp->size), (long) (sectp->size));
909 header_offset += sizeof (struct section);
910 sectp++;
913 curr_file_offset += ROUNDUP_TO_PAGE_BOUNDARY (scp->filesize);
915 if (!unexec_write (curr_header_offset, scp, sizeof (struct segment_command)))
916 unexec_error ("cannot write header of __DATA segment");
917 curr_header_offset += lc->cmdsize;
919 /* Create new __DATA segment load commands for regions on the region
920 list that do not corresponding to any segment load commands in
921 the input file.
923 for (j = 0; j < num_unexec_regions; j++)
925 struct segment_command sc;
927 sc.cmd = LC_SEGMENT;
928 sc.cmdsize = sizeof (struct segment_command);
929 strncpy (sc.segname, SEG_DATA, 16);
930 sc.vmaddr = unexec_regions[j].range.address;
931 sc.vmsize = unexec_regions[j].range.size;
932 sc.fileoff = curr_file_offset;
933 sc.filesize = unexec_regions[j].filesize;
934 sc.maxprot = VM_PROT_READ | VM_PROT_WRITE;
935 sc.initprot = VM_PROT_READ | VM_PROT_WRITE;
936 sc.nsects = 0;
937 sc.flags = 0;
939 printf ("Writing segment %-16.16s @ %#8lx (%#8lx/%#8lx @ %#10lx)\n",
940 sc.segname, (long) (sc.fileoff), (long) (sc.filesize),
941 (long) (sc.vmsize), (long) (sc.vmaddr));
943 if (!unexec_write (sc.fileoff, (void *) sc.vmaddr, sc.filesize))
944 unexec_error ("cannot write new __DATA segment");
945 curr_file_offset += ROUNDUP_TO_PAGE_BOUNDARY (sc.filesize);
947 if (!unexec_write (curr_header_offset, &sc, sc.cmdsize))
948 unexec_error ("cannot write new __DATA segment's header");
949 curr_header_offset += sc.cmdsize;
950 mh.ncmds++;
954 /* Copy a LC_SYMTAB load command from the input file to the output
955 file, adjusting the file offset fields. */
956 static void
957 copy_symtab (struct load_command *lc, long delta)
959 struct symtab_command *stp = (struct symtab_command *) lc;
961 stp->symoff += delta;
962 stp->stroff += delta;
964 printf ("Writing LC_SYMTAB command\n");
966 if (!unexec_write (curr_header_offset, lc, lc->cmdsize))
967 unexec_error ("cannot write symtab command to header");
969 curr_header_offset += lc->cmdsize;
972 /* Fix up relocation entries. */
973 static void
974 unrelocate (const char *name, off_t reloff, int nrel, vm_address_t base)
976 int i, unreloc_count;
977 struct relocation_info reloc_info;
978 struct scattered_relocation_info *sc_reloc_info
979 = (struct scattered_relocation_info *) &reloc_info;
980 vm_address_t location;
982 for (unreloc_count = 0, i = 0; i < nrel; i++)
984 if (lseek (infd, reloff, L_SET) != reloff)
985 unexec_error ("unrelocate: %s:%d cannot seek to reloc_info", name, i);
986 if (!unexec_read (&reloc_info, sizeof (reloc_info)))
987 unexec_error ("unrelocate: %s:%d cannot read reloc_info", name, i);
988 reloff += sizeof (reloc_info);
990 if (sc_reloc_info->r_scattered == 0)
991 switch (reloc_info.r_type)
993 case GENERIC_RELOC_VANILLA:
994 location = base + reloc_info.r_address;
995 if (location >= data_segment_scp->vmaddr
996 && location < (data_segment_scp->vmaddr
997 + data_segment_scp->vmsize))
999 off_t src_off = data_segment_old_fileoff
1000 + (location - data_segment_scp->vmaddr);
1001 off_t dst_off = data_segment_scp->fileoff
1002 + (location - data_segment_scp->vmaddr);
1004 if (!unexec_copy (dst_off, src_off, 1 << reloc_info.r_length))
1005 unexec_error ("unrelocate: %s:%d cannot copy original value",
1006 name, i);
1007 unreloc_count++;
1009 break;
1010 default:
1011 unexec_error ("unrelocate: %s:%d cannot handle type = %d",
1012 name, i, reloc_info.r_type);
1014 else
1015 switch (sc_reloc_info->r_type)
1017 #if defined (__ppc__)
1018 case PPC_RELOC_PB_LA_PTR:
1019 /* nothing to do for prebound lazy pointer */
1020 break;
1021 #endif
1022 default:
1023 unexec_error ("unrelocate: %s:%d cannot handle scattered type = %d",
1024 name, i, sc_reloc_info->r_type);
1028 if (nrel > 0)
1029 printf ("Fixed up %d/%d %s relocation entries in data segment.\n",
1030 unreloc_count, nrel, name);
1033 #if __ppc64__
1034 /* Rebase r_address in the relocation table. */
1035 static void
1036 rebase_reloc_address (off_t reloff, int nrel, long linkedit_delta, long diff)
1038 int i;
1039 struct relocation_info reloc_info;
1040 struct scattered_relocation_info *sc_reloc_info
1041 = (struct scattered_relocation_info *) &reloc_info;
1043 for (i = 0; i < nrel; i++, reloff += sizeof (reloc_info))
1045 if (lseek (infd, reloff - linkedit_delta, L_SET)
1046 != reloff - linkedit_delta)
1047 unexec_error ("rebase_reloc_table: cannot seek to reloc_info");
1048 if (!unexec_read (&reloc_info, sizeof (reloc_info)))
1049 unexec_error ("rebase_reloc_table: cannot read reloc_info");
1051 if (sc_reloc_info->r_scattered == 0
1052 && reloc_info.r_type == GENERIC_RELOC_VANILLA)
1054 reloc_info.r_address -= diff;
1055 if (!unexec_write (reloff, &reloc_info, sizeof (reloc_info)))
1056 unexec_error ("rebase_reloc_table: cannot write reloc_info");
1060 #endif
1062 /* Copy a LC_DYSYMTAB load command from the input file to the output
1063 file, adjusting the file offset fields. */
1064 static void
1065 copy_dysymtab (struct load_command *lc, long delta)
1067 struct dysymtab_command *dstp = (struct dysymtab_command *) lc;
1068 vm_address_t base;
1070 #ifdef _LP64
1071 #if __ppc64__
1073 int i;
1075 base = 0;
1076 for (i = 0; i < nlc; i++)
1077 if (lca[i]->cmd == LC_SEGMENT)
1079 struct segment_command *scp = (struct segment_command *) lca[i];
1081 if (scp->vmaddr + scp->vmsize > 0x100000000
1082 && (scp->initprot & VM_PROT_WRITE) != 0)
1084 base = data_segment_scp->vmaddr;
1085 break;
1089 #else
1090 /* First writable segment address. */
1091 base = data_segment_scp->vmaddr;
1092 #endif
1093 #else
1094 /* First segment address in the file (unless MH_SPLIT_SEGS set). */
1095 base = 0;
1096 #endif
1098 unrelocate ("local", dstp->locreloff, dstp->nlocrel, base);
1099 unrelocate ("external", dstp->extreloff, dstp->nextrel, base);
1101 if (dstp->nextrel > 0) {
1102 dstp->extreloff += delta;
1105 if (dstp->nlocrel > 0) {
1106 dstp->locreloff += delta;
1109 if (dstp->nindirectsyms > 0)
1110 dstp->indirectsymoff += delta;
1112 printf ("Writing LC_DYSYMTAB command\n");
1114 if (!unexec_write (curr_header_offset, lc, lc->cmdsize))
1115 unexec_error ("cannot write symtab command to header");
1117 curr_header_offset += lc->cmdsize;
1119 #if __ppc64__
1120 /* Check if the relocation base needs to be changed. */
1121 if (base == 0)
1123 vm_address_t newbase = 0;
1124 int i;
1126 for (i = 0; i < num_unexec_regions; i++)
1127 if (unexec_regions[i].range.address + unexec_regions[i].range.size
1128 > 0x100000000)
1130 newbase = data_segment_scp->vmaddr;
1131 break;
1134 if (newbase)
1136 rebase_reloc_address (dstp->locreloff, dstp->nlocrel, delta, newbase);
1137 rebase_reloc_address (dstp->extreloff, dstp->nextrel, delta, newbase);
1140 #endif
1143 /* Copy a LC_TWOLEVEL_HINTS load command from the input file to the output
1144 file, adjusting the file offset fields. */
1145 static void
1146 copy_twolevelhints (struct load_command *lc, long delta)
1148 struct twolevel_hints_command *tlhp = (struct twolevel_hints_command *) lc;
1150 if (tlhp->nhints > 0) {
1151 tlhp->offset += delta;
1154 printf ("Writing LC_TWOLEVEL_HINTS command\n");
1156 if (!unexec_write (curr_header_offset, lc, lc->cmdsize))
1157 unexec_error ("cannot write two level hint command to header");
1159 curr_header_offset += lc->cmdsize;
1162 #ifdef LC_DYLD_INFO
1163 /* Copy a LC_DYLD_INFO(_ONLY) load command from the input file to the output
1164 file, adjusting the file offset fields. */
1165 static void
1166 copy_dyld_info (struct load_command *lc, long delta)
1168 struct dyld_info_command *dip = (struct dyld_info_command *) lc;
1170 if (dip->rebase_off > 0)
1171 dip->rebase_off += delta;
1172 if (dip->bind_off > 0)
1173 dip->bind_off += delta;
1174 if (dip->weak_bind_off > 0)
1175 dip->weak_bind_off += delta;
1176 if (dip->lazy_bind_off > 0)
1177 dip->lazy_bind_off += delta;
1178 if (dip->export_off > 0)
1179 dip->export_off += delta;
1181 printf ("Writing ");
1182 print_load_command_name (lc->cmd);
1183 printf (" command\n");
1185 if (!unexec_write (curr_header_offset, lc, lc->cmdsize))
1186 unexec_error ("cannot write dyld info command to header");
1188 curr_header_offset += lc->cmdsize;
1190 #endif
1192 #ifdef LC_FUNCTION_STARTS
1193 /* Copy a LC_FUNCTION_STARTS/LC_DATA_IN_CODE/LC_DYLIB_CODE_SIGN_DRS
1194 load command from the input file to the output file, adjusting the
1195 data offset field. */
1196 static void
1197 copy_linkedit_data (struct load_command *lc, long delta)
1199 struct linkedit_data_command *ldp = (struct linkedit_data_command *) lc;
1201 if (ldp->dataoff > 0)
1202 ldp->dataoff += delta;
1204 printf ("Writing ");
1205 print_load_command_name (lc->cmd);
1206 printf (" command\n");
1208 if (!unexec_write (curr_header_offset, lc, lc->cmdsize))
1209 unexec_error ("cannot write linkedit data command to header");
1211 curr_header_offset += lc->cmdsize;
1213 #endif
1215 /* Copy other kinds of load commands from the input file to the output
1216 file, ones that do not require adjustments of file offsets. */
1217 static void
1218 copy_other (struct load_command *lc)
1220 printf ("Writing ");
1221 print_load_command_name (lc->cmd);
1222 printf (" command\n");
1224 if (!unexec_write (curr_header_offset, lc, lc->cmdsize))
1225 unexec_error ("cannot write symtab command to header");
1227 curr_header_offset += lc->cmdsize;
1230 /* Loop through all load commands and dump them. Then write the Mach
1231 header. */
1232 static void
1233 dump_it (void)
1235 int i;
1236 long linkedit_delta = 0;
1238 printf ("--- Load Commands written to Output File ---\n");
1240 for (i = 0; i < nlc; i++)
1241 switch (lca[i]->cmd)
1243 case LC_SEGMENT:
1245 struct segment_command *scp = (struct segment_command *) lca[i];
1246 if (strncmp (scp->segname, SEG_DATA, 16) == 0)
1248 /* save data segment file offset and segment_command for
1249 unrelocate */
1250 if (data_segment_old_fileoff)
1251 unexec_error ("cannot handle multiple DATA segments"
1252 " in input file");
1253 data_segment_old_fileoff = scp->fileoff;
1254 data_segment_scp = scp;
1256 copy_data_segment (lca[i]);
1258 else
1260 if (strncmp (scp->segname, SEG_LINKEDIT, 16) == 0)
1262 if (linkedit_delta)
1263 unexec_error ("cannot handle multiple LINKEDIT segments"
1264 " in input file");
1265 linkedit_delta = curr_file_offset - scp->fileoff;
1268 copy_segment (lca[i]);
1271 break;
1272 case LC_SYMTAB:
1273 copy_symtab (lca[i], linkedit_delta);
1274 break;
1275 case LC_DYSYMTAB:
1276 copy_dysymtab (lca[i], linkedit_delta);
1277 break;
1278 case LC_TWOLEVEL_HINTS:
1279 copy_twolevelhints (lca[i], linkedit_delta);
1280 break;
1281 #ifdef LC_DYLD_INFO
1282 case LC_DYLD_INFO:
1283 case LC_DYLD_INFO_ONLY:
1284 copy_dyld_info (lca[i], linkedit_delta);
1285 break;
1286 #endif
1287 #ifdef LC_FUNCTION_STARTS
1288 case LC_FUNCTION_STARTS:
1289 #ifdef LC_DATA_IN_CODE
1290 case LC_DATA_IN_CODE:
1291 #endif
1292 #ifdef LC_DYLIB_CODE_SIGN_DRS
1293 case LC_DYLIB_CODE_SIGN_DRS:
1294 #endif
1295 copy_linkedit_data (lca[i], linkedit_delta);
1296 break;
1297 #endif
1298 default:
1299 copy_other (lca[i]);
1300 break;
1303 if (curr_header_offset > text_seg_lowest_offset)
1304 unexec_error ("not enough room for load commands for new __DATA segments");
1306 printf ("%ld unused bytes follow Mach-O header\n",
1307 text_seg_lowest_offset - curr_header_offset);
1309 mh.sizeofcmds = curr_header_offset - sizeof (struct mach_header);
1310 if (!unexec_write (0, &mh, sizeof (struct mach_header)))
1311 unexec_error ("cannot write final header contents");
1314 /* Take a snapshot of Emacs and make a Mach-O format executable file
1315 from it. The file names of the output and input files are outfile
1316 and infile, respectively. The three other parameters are
1317 ignored. */
1318 void
1319 unexec (const char *outfile, const char *infile)
1321 if (in_dumped_exec)
1322 unexec_error ("Unexec from a dumped executable is not supported.");
1324 pagesize = getpagesize ();
1325 infd = open (infile, O_RDONLY, 0);
1326 if (infd < 0)
1328 unexec_error ("cannot open input file `%s'", infile);
1331 outfd = open (outfile, O_WRONLY | O_TRUNC | O_CREAT, 0755);
1332 if (outfd < 0)
1334 close (infd);
1335 unexec_error ("cannot open output file `%s'", outfile);
1338 build_region_list ();
1339 read_load_commands ();
1341 find_emacs_zone_regions ();
1342 unexec_regions_merge ();
1344 in_dumped_exec = 1;
1346 dump_it ();
1348 close (outfd);
1352 void
1353 unexec_init_emacs_zone (void)
1355 emacs_zone = malloc_create_zone (0, 0);
1356 malloc_set_zone_name (emacs_zone, "EmacsZone");
1359 #ifndef MACOSX_MALLOC_MULT16
1360 #define MACOSX_MALLOC_MULT16 1
1361 #endif
1363 typedef struct unexec_malloc_header {
1364 union {
1365 char c[8];
1366 size_t size;
1367 } u;
1368 } unexec_malloc_header_t;
1370 #if MACOSX_MALLOC_MULT16
1372 #define ptr_in_unexec_regions(p) ((((vm_address_t) (p)) & 8) != 0)
1374 #else
1377 ptr_in_unexec_regions (void *ptr)
1379 int i;
1381 for (i = 0; i < num_unexec_regions; i++)
1382 if ((vm_address_t) ptr - unexec_regions[i].range.address
1383 < unexec_regions[i].range.size)
1384 return 1;
1386 return 0;
1389 #endif
1391 void *
1392 unexec_malloc (size_t size)
1394 if (in_dumped_exec)
1396 void *p;
1398 p = malloc (size);
1399 #if MACOSX_MALLOC_MULT16
1400 assert (((vm_address_t) p % 16) == 0);
1401 #endif
1402 return p;
1404 else
1406 unexec_malloc_header_t *ptr;
1408 ptr = (unexec_malloc_header_t *)
1409 malloc_zone_malloc (emacs_zone, size + sizeof (unexec_malloc_header_t));
1410 ptr->u.size = size;
1411 ptr++;
1412 #if MACOSX_MALLOC_MULT16
1413 assert (((vm_address_t) ptr % 16) == 8);
1414 #endif
1415 return (void *) ptr;
1419 void *
1420 unexec_realloc (void *old_ptr, size_t new_size)
1422 if (in_dumped_exec)
1424 void *p;
1426 if (ptr_in_unexec_regions (old_ptr))
1428 size_t old_size = ((unexec_malloc_header_t *) old_ptr)[-1].u.size;
1429 size_t size = new_size > old_size ? old_size : new_size;
1431 p = malloc (new_size);
1432 if (size)
1433 memcpy (p, old_ptr, size);
1435 else
1437 p = realloc (old_ptr, new_size);
1439 #if MACOSX_MALLOC_MULT16
1440 assert (((vm_address_t) p % 16) == 0);
1441 #endif
1442 return p;
1444 else
1446 unexec_malloc_header_t *ptr;
1448 ptr = (unexec_malloc_header_t *)
1449 malloc_zone_realloc (emacs_zone, (unexec_malloc_header_t *) old_ptr - 1,
1450 new_size + sizeof (unexec_malloc_header_t));
1451 ptr->u.size = new_size;
1452 ptr++;
1453 #if MACOSX_MALLOC_MULT16
1454 assert (((vm_address_t) ptr % 16) == 8);
1455 #endif
1456 return (void *) ptr;
1460 void
1461 unexec_free (void *ptr)
1463 if (ptr == NULL)
1464 return;
1465 if (in_dumped_exec)
1467 if (!ptr_in_unexec_regions (ptr))
1468 free (ptr);
1470 else
1471 malloc_zone_free (emacs_zone, (unexec_malloc_header_t *) ptr - 1);