1 /* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992
2 Free Software Foundation, Inc.
4 This file is part of XEmacs.
6 XEmacs is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by the
8 Free Software Foundation; either version 2, or (at your option) any
11 XEmacs is distributed in the hope that it will be useful, but WITHOUT
12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with XEmacs; see the file COPYING. If not, write to
18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
21 /* Synched up with: FSF 19.31. */
25 * unexec.c - Convert a running program into an a.out file.
27 * Author: Spencer W. Thomas
28 * Computer Science Dept.
30 * Date: Tue Mar 2 1982
31 * Modified heavily since then.
34 * unexec (new_name, a_name, data_start, bss_start, entry_address)
35 * char *new_name, *a_name;
36 * unsigned data_start, bss_start, entry_address;
38 * Takes a snapshot of the program and makes an a.out format file in the
39 * file named by the string argument new_name.
40 * If a_name is non-NULL, the symbol table will be taken from the given file.
41 * On some machines, an existing a_name file is required.
43 * The boundaries within the a.out file may be adjusted with the data_start
44 * and bss_start arguments. Either or both may be given as 0 for defaults.
46 * Data_start gives the boundary between the text segment and the data
47 * segment of the program. The text segment can contain shared, read-only
48 * program code and literal data, while the data segment is always unshared
49 * and unprotected. Data_start gives the lowest unprotected address.
50 * The value you specify may be rounded down to a suitable boundary
51 * as required by the machine you are using.
53 * Specifying zero for data_start means the boundary between text and data
54 * should not be the same as when the program was loaded.
55 * If NO_REMAP is defined, the argument data_start is ignored and the
56 * segment boundaries are never changed.
58 * Bss_start indicates how much of the data segment is to be saved in the
59 * a.out file and restored when the program is executed. It gives the lowest
60 * unsaved address, and is rounded up to a page boundary. The default when 0
61 * is given assumes that the entire data segment is to be stored, including
62 * the previous data and bss as well as any additional storage allocated with
65 * The new file is set up to start at entry_address.
67 * If you make improvements I'd like to get them too.
68 * harpo!utah-cs!thomas, thomas@Utah-20
72 /* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
75 * Basic theory: the data space of the running process needs to be
76 * dumped to the output file. Normally we would just enlarge the size
77 * of .data, scooting everything down. But we can't do that in ELF,
78 * because there is often something between the .data space and the
81 * In the temacs dump below, notice that the Global Offset Table
82 * (.got) and the Dynamic link data (.dynamic) come between .data1 and
83 * .bss. It does not work to overlap .data with these fields.
85 * The solution is to create a new .data segment. This segment is
86 * filled with data from the current process. Since the contents of
87 * various sections refer to sections by index, the new .data segment
88 * is made the last in the table to avoid changing any existing index.
90 * This is an example of how the section headers are changed. "Addr"
91 * is a process virtual address. "Offset" is a file offset.
93 raid:/nfs/raid/src/dist-18.56/src> dump -h temacs
97 **** SECTION HEADER TABLE ****
98 [No] Type Flags Addr Offset Size Name
99 Link Info Adralgn Entsize
101 [1] 1 2 0x80480d4 0xd4 0x13 .interp
104 [2] 5 2 0x80480e8 0xe8 0x388 .hash
107 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
110 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
113 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
116 [6] 1 6 0x8049348 0x1348 0x3 .init
119 [7] 1 6 0x804934c 0x134c 0x680 .plt
122 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
125 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
128 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
131 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
134 [12] 1 3 0x8088330 0x3f330 0x20afc .data
137 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
140 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
143 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
146 [16] 8 3 0x80a98f4 0x608f4 0x449c .bss
149 [17] 2 0 0 0x608f4 0x9b90 .symtab
152 [18] 3 0 0 0x6a484 0x8526 .strtab
155 [19] 3 0 0 0x729aa 0x93 .shstrtab
158 [20] 1 0 0 0x72a3d 0x68b7 .comment
161 raid:/nfs/raid/src/dist-18.56/src> dump -h xemacs
165 **** SECTION HEADER TABLE ****
166 [No] Type Flags Addr Offset Size Name
167 Link Info Adralgn Entsize
169 [1] 1 2 0x80480d4 0xd4 0x13 .interp
172 [2] 5 2 0x80480e8 0xe8 0x388 .hash
175 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
178 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
181 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
184 [6] 1 6 0x8049348 0x1348 0x3 .init
187 [7] 1 6 0x804934c 0x134c 0x680 .plt
190 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
193 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
196 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
199 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
202 [12] 1 3 0x8088330 0x3f330 0x20afc .data
205 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
208 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
211 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
214 [16] 8 3 0x80c6800 0x7d800 0 .bss
217 [17] 2 0 0 0x7d800 0x9b90 .symtab
220 [18] 3 0 0 0x87390 0x8526 .strtab
223 [19] 3 0 0 0x8f8b6 0x93 .shstrtab
226 [20] 1 0 0 0x8f949 0x68b7 .comment
229 [21] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
232 * This is an example of how the file header is changed. "Shoff" is
233 * the section header offset within the file. Since that table is
234 * after the new .data section, it is moved. "Shnum" is the number of
235 * sections, which we increment.
237 * "Phoff" is the file offset to the program header. "Phentsize" and
238 * "Shentsz" are the program and section header entries sizes respectively.
239 * These can be larger than the apparent struct sizes.
241 raid:/nfs/raid/src/dist-18.56/src> dump -f temacs
246 Class Data Type Machine Version
247 Entry Phoff Shoff Flags Ehsize
248 Phentsize Phnum Shentsz Shnum Shstrndx
251 0x80499cc 0x34 0x792f4 0 0x34
254 raid:/nfs/raid/src/dist-18.56/src> dump -f xemacs
259 Class Data Type Machine Version
260 Entry Phoff Shoff Flags Ehsize
261 Phentsize Phnum Shentsz Shnum Shstrndx
264 0x80499cc 0x34 0x96200 0 0x34
267 * These are the program headers. "Offset" is the file offset to the
268 * segment. "Vaddr" is the memory load address. "Filesz" is the
269 * segment size as it appears in the file, and "Memsz" is the size in
270 * memory. Below, the third segment is the code and the fourth is the
271 * data: the difference between Filesz and Memsz is .bss
273 raid:/nfs/raid/src/dist-18.56/src> dump -o temacs
276 ***** PROGRAM EXECUTION HEADER *****
277 Type Offset Vaddr Paddr
278 Filesz Memsz Flags Align
287 0x3f2f9 0x3f2f9 5 0x1000
289 1 0x3f330 0x8088330 0
290 0x215c4 0x25a60 7 0x1000
292 2 0x60874 0x80a9874 0
295 raid:/nfs/raid/src/dist-18.56/src> dump -o xemacs
298 ***** PROGRAM EXECUTION HEADER *****
299 Type Offset Vaddr Paddr
300 Filesz Memsz Flags Align
309 0x3f2f9 0x3f2f9 5 0x1000
311 1 0x3f330 0x8088330 0
312 0x3e4d0 0x3e4d0 7 0x1000
314 2 0x60874 0x80a9874 0
320 /* Modified by wtien@urbana.mcd.mot.com of Motorola Inc.
322 * The above mechanism does not work if the unexeced ELF file is being
323 * re-layout by other applications (such as `strip'). All the applications
324 * that re-layout the internal of ELF will layout all sections in ascending
325 * order of their file offsets. After the re-layout, the data2 section will
326 * still be the LAST section in the section header vector, but its file offset
327 * is now being pushed far away down, and causes part of it not to be mapped
328 * in (ie. not covered by the load segment entry in PHDR vector), therefore
329 * causes the new binary to fail.
331 * The solution is to modify the unexec algorithm to insert the new data2
332 * section header right before the new bss section header, so their file
333 * offsets will be in the ascending order. Since some of the section's (all
334 * sections AFTER the bss section) indexes are now changed, we also need to
335 * modify some fields to make them point to the right sections. This is done
336 * by macro PATCH_INDEX. All the fields that need to be patched are:
338 * 1. ELF header e_shstrndx field.
339 * 2. section header sh_link and sh_info field.
340 * 3. symbol table entry st_shndx field.
342 * The above example now should look like:
344 **** SECTION HEADER TABLE ****
345 [No] Type Flags Addr Offset Size Name
346 Link Info Adralgn Entsize
348 [1] 1 2 0x80480d4 0xd4 0x13 .interp
351 [2] 5 2 0x80480e8 0xe8 0x388 .hash
354 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
357 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
360 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
363 [6] 1 6 0x8049348 0x1348 0x3 .init
366 [7] 1 6 0x804934c 0x134c 0x680 .plt
369 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
372 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
375 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
378 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
381 [12] 1 3 0x8088330 0x3f330 0x20afc .data
384 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
387 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
390 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
393 [16] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
396 [17] 8 3 0x80c6800 0x7d800 0 .bss
399 [18] 2 0 0 0x7d800 0x9b90 .symtab
402 [19] 3 0 0 0x87390 0x8526 .strtab
405 [20] 3 0 0 0x8f8b6 0x93 .shstrtab
408 [21] 1 0 0 0x8f949 0x68b7 .comment
413 /* More mods, by Jack Repenning <jackr@sgi.com>, Fri Aug 11 15:45:52 1995
415 Same algorithm as immediately above. However, the detailed
416 calculations of the various locations needed significant
419 At the point of the old .bss, the file offsets and the memory
420 addresses do distinct, slightly snaky things:
422 offset of .bss is meaningless and unpredictable
423 addr of .bss is meaningful
424 alignment of .bss is important to addr, so there may be a small
425 gap in address range before start of bss
426 offset of next section is rounded up modulo 0x1000
427 the hole so-introduced is zero-filled, so it can be mapped in as
428 the first partial-page of bss (the rest of the bss is mapped from
430 I suppose you could view this not as a hole, but as the beginning
431 of the bss, actually present in the file. But you should not
432 push that worldview too far, as the linker still knows that the
433 "offset" claimed for the bss is unused, and seems not always
434 careful about setting it.
436 We are doing all our tricks at this same rather complicated
437 location (isn't life fun?):
439 insert a new data section to contain now-initialized old bss and
441 define a zero-length bss just so there is one
443 The offset of the new data section is dictated by its current
444 address (which, of course, we want also to be its addr): the
445 loader maps in the whole file region containing old data, rodata,
446 got, and new data as a single mapped segment, starting at the
447 address of the first chunk; the rest have to be laid out in the
448 file such that the map into the right spots. That is:
451 addrInRunningMemory(newdata)-aIRM(olddata)
454 This would not necessarily match the oldbss offset, even if it
455 were carefully calculated! We must compute this.
457 The linker that built temacs has also already arranged that
458 olddata is properly page-aligned (not necessarily beginning on a
459 page, but rather that a page's worth of the low bits of addr and
460 offset match). We preserve this.
462 addr(bss) is alignment-constrained from the end of the new data.
463 Since we base endof(newdata) on sbrk(), we have a page boundary
464 (in both offset and addr) and meet any alignment constraint,
465 needing no alignment adjustment of this location and no
466 mini-hole. Or, if you like, we've allowed sbrk() to "compute"
467 the mini-hole size for us.
469 That puts newbss beginning on a page boundary, both in offset and
470 addr. (offset(bss) is still meaningless, but what the heck,
473 Since newbss has zero length, and its offset (however
474 meaningless) is page aligned, we place the next section exactly
475 there, with no hole needed to restore page alignment.
477 So, the shift for all sections beyond the playing field is:
479 new_bss_addr - roundup(old_bss_addr,0x1000)
482 /* Still more mods... Olivier Galibert 19971705
483 - support for .sbss section (automagically changed to data without
485 - support for 64bits ABI (will need a bunch of fixes in the rest
486 of the code before it works
489 #include <sys/types.h>
491 #include <sys/stat.h>
498 #include <sym.h> /* for HDRR declaration */
499 #include <sys/mman.h>
503 /* in 64bits mode, use 64bits elf */
505 typedef Elf64_Shdr l_Elf_Shdr;
506 typedef Elf64_Phdr l_Elf_Phdr;
507 typedef Elf64_Ehdr l_Elf_Ehdr;
508 typedef Elf64_Addr l_Elf_Addr;
509 typedef Elf64_Word l_Elf_Word;
510 typedef Elf64_Off l_Elf_Off;
511 typedef Elf64_Sym l_Elf_Sym;
513 typedef Elf32_Shdr l_Elf_Shdr;
514 typedef Elf32_Phdr l_Elf_Phdr;
515 typedef Elf32_Ehdr l_Elf_Ehdr;
516 typedef Elf32_Addr l_Elf_Addr;
517 typedef Elf32_Word l_Elf_Word;
518 typedef Elf32_Off l_Elf_Off;
519 typedef Elf32_Sym l_Elf_Sym;
523 /* Get the address of a particular section or program header entry,
524 * accounting for the size of the entries.
527 #define OLD_SECTION_H(n) \
528 (*(l_Elf_Shdr *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
529 #define NEW_SECTION_H(n) \
530 (*(l_Elf_Shdr *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
531 #define OLD_PROGRAM_H(n) \
532 (*(l_Elf_Phdr *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
533 #define NEW_PROGRAM_H(n) \
534 (*(l_Elf_Phdr *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
536 #define PATCH_INDEX(n) \
538 if ((n) >= old_bss_index) \
540 typedef unsigned char byte;
542 /* Round X up to a multiple of Y. */
554 /* Return the index of the section named NAME.
555 SECTION_NAMES, FILE_NAME and FILE_H give information
556 about the file we are looking in.
558 If we don't find the section NAME, that is a fatal error
559 if NOERROR is 0; we return -1 if NOERROR is nonzero. */
562 find_section (name, section_names, file_name, old_file_h, old_section_h, noerror)
566 l_Elf_Ehdr *old_file_h;
567 l_Elf_Shdr *old_section_h;
572 for (idx = 1; idx < old_file_h->e_shnum; idx++)
575 fprintf (stderr, "Looking for %s - found %s\n", name,
576 section_names + OLD_SECTION_H (idx).sh_name);
578 if (!strcmp (section_names + OLD_SECTION_H (idx).sh_name,
582 if (idx == old_file_h->e_shnum)
587 fatal ("Can't find .bss in %s.\n", file_name);
593 /* ****************************************************************
598 * In ELF, this works by replacing the old .bss section with a new
599 * .data section, and inserting an empty .bss immediately afterwards.
603 unexec (new_name, old_name, data_start, bss_start, entry_address)
604 char *new_name, *old_name;
605 uintptr_t data_start, bss_start, entry_address;
607 extern uintptr_t bss_end;
608 int new_file, old_file, new_file_size;
610 /* Pointers to the base of the image of the two files. */
611 caddr_t old_base, new_base;
613 /* Pointers to the file, program and section headers for the old and new
615 l_Elf_Ehdr *old_file_h, *new_file_h;
616 l_Elf_Phdr *old_program_h, *new_program_h;
617 l_Elf_Shdr *old_section_h, *new_section_h;
619 /* Point to the section name table in the old file. */
620 char *old_section_names;
622 l_Elf_Addr old_bss_addr, new_bss_addr;
623 l_Elf_Addr old_base_addr;
624 l_Elf_Word old_bss_size, new_data2_size;
625 l_Elf_Off new_data2_offset, new_base_offset;
626 l_Elf_Addr new_data2_addr;
627 l_Elf_Addr new_offsets_shift;
629 int n, nn, old_bss_index, old_data_index;
630 int old_mdebug_index, old_sbss_index;
631 struct stat stat_buf;
633 /* Open the old file & map it into the address space. */
635 old_file = open (old_name, O_RDONLY);
638 fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
640 if (fstat (old_file, &stat_buf) == -1)
641 fatal ("Can't fstat(%s): errno %d\n", old_name, errno);
643 old_base = mmap (0, stat_buf.st_size, PROT_READ, MAP_SHARED, old_file, 0);
645 if (old_base == (caddr_t) -1)
646 fatal ("Can't mmap(%s): errno %d\n", old_name, errno);
649 fprintf (stderr, "mmap(%s, %x) -> %x\n", old_name, stat_buf.st_size,
653 /* Get pointers to headers & section names. */
655 old_file_h = (l_Elf_Ehdr *) old_base;
656 old_program_h = (l_Elf_Phdr *) ((byte *) old_base + old_file_h->e_phoff);
657 old_section_h = (l_Elf_Shdr *) ((byte *) old_base + old_file_h->e_shoff);
659 = (char *) old_base + OLD_SECTION_H (old_file_h->e_shstrndx).sh_offset;
661 /* Find the mdebug section, if any. */
663 old_mdebug_index = find_section (".mdebug", old_section_names,
664 old_name, old_file_h, old_section_h, 1);
666 /* Find the .sbss section, if any. */
668 old_sbss_index = find_section (".sbss", old_section_names,
669 old_name, old_file_h, old_section_h, 1);
671 if (old_sbss_index != -1 && (OLD_SECTION_H (old_sbss_index).sh_type == SHT_PROGBITS))
674 /* Find the old .bss section. */
676 old_bss_index = find_section (".bss", old_section_names,
677 old_name, old_file_h, old_section_h, 0);
679 /* Find the old .data section. Figure out parameters of
680 the new data2 and bss sections. */
682 old_data_index = find_section (".data", old_section_names,
683 old_name, old_file_h, old_section_h, 0);
685 old_bss_addr = OLD_SECTION_H (old_bss_index).sh_addr;
686 old_bss_size = OLD_SECTION_H (old_bss_index).sh_size;
687 old_base_addr = old_sbss_index == -1 ? old_bss_addr : OLD_SECTION_H (old_sbss_index).sh_addr;
688 #if defined(emacs) || !defined(DEBUG)
689 bss_end = (uintptr_t) sbrk (0);
690 new_bss_addr = (l_Elf_Addr) bss_end;
692 new_bss_addr = old_bss_addr + old_bss_size + 0x1234;
694 new_data2_addr = old_bss_addr;
695 new_data2_size = new_bss_addr - old_bss_addr;
696 new_data2_offset = OLD_SECTION_H (old_data_index).sh_offset +
697 (new_data2_addr - OLD_SECTION_H (old_data_index).sh_addr);
698 new_base_offset = OLD_SECTION_H (old_data_index).sh_offset +
699 (old_base_addr - OLD_SECTION_H (old_data_index).sh_addr);
700 new_offsets_shift = new_bss_addr -
701 ((old_base_addr & ~0xfff) + ((old_base_addr & 0xfff) ? 0x1000 : 0));
704 fprintf (stderr, "old_bss_index %d\n", old_bss_index);
705 fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
706 fprintf (stderr, "old_bss_size %x\n", old_bss_size);
707 fprintf (stderr, "old_base_addr %x\n", old_base_addr);
708 fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
709 fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
710 fprintf (stderr, "new_data2_size %x\n", new_data2_size);
711 fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
712 fprintf (stderr, "new_offsets_shift %x\n", new_offsets_shift);
715 if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
716 fatal (".bss shrank when undumping???\n");
718 /* Set the output file to the right size and mmap it. Set
719 pointers to various interesting objects. stat_buf still has
722 new_file = open (new_name, O_RDWR | O_CREAT, 0666);
724 fatal ("Can't creat (%s): errno %d\n", new_name, errno);
726 new_file_size = stat_buf.st_size /* old file size */
727 + old_file_h->e_shentsize /* one new section header */
728 + new_offsets_shift; /* trailing section shift */
730 if (ftruncate (new_file, new_file_size))
731 fatal ("Can't ftruncate (%s): errno %d\n", new_name, errno);
733 new_base = mmap (0, new_file_size, PROT_READ | PROT_WRITE, MAP_SHARED,
736 if (new_base == (caddr_t) -1)
737 fatal ("Can't mmap (%s): errno %d\n", new_name, errno);
739 new_file_h = (l_Elf_Ehdr *) new_base;
740 new_program_h = (l_Elf_Phdr *) ((byte *) new_base + old_file_h->e_phoff);
742 = (l_Elf_Shdr *) ((byte *) new_base + old_file_h->e_shoff
743 + new_offsets_shift);
745 /* Make our new file, program and section headers as copies of the
748 memcpy (new_file_h, old_file_h, old_file_h->e_ehsize);
749 memcpy (new_program_h, old_program_h,
750 old_file_h->e_phnum * old_file_h->e_phentsize);
752 /* Modify the e_shstrndx if necessary. */
753 PATCH_INDEX (new_file_h->e_shstrndx);
755 /* Fix up file header. We'll add one section. Section header is
758 new_file_h->e_shoff += new_offsets_shift;
759 new_file_h->e_shnum += 1;
763 fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff);
764 fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum);
765 fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff);
766 fprintf (stderr, "New section count %d\n", new_file_h->e_shnum);
769 /* Fix up a new program header. Extend the writable data segment so
770 that the bss area is covered too. Find that segment by looking
771 for a segment that ends just before the .bss area. Make sure
772 that no segments are above the new .data2. Put a loop at the end
773 to adjust the offset and address of any segment that is above
774 data2, just in case we decide to allow this later. */
776 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
778 /* Compute maximum of all requirements for alignment of section. */
779 int alignment = (NEW_PROGRAM_H (n)).p_align;
780 if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment)
781 alignment = OLD_SECTION_H (old_bss_index).sh_addralign;
783 /* Supposedly this condition is okay for the SGI. */
785 if (NEW_PROGRAM_H (n).p_vaddr + NEW_PROGRAM_H (n).p_filesz > old_base_addr)
786 fatal ("Program segment above .bss in %s\n", old_name);
789 if (NEW_PROGRAM_H (n).p_type == PT_LOAD
790 && (round_up ((NEW_PROGRAM_H (n)).p_vaddr
791 + (NEW_PROGRAM_H (n)).p_filesz,
793 == round_up (old_base_addr, alignment)))
797 fatal ("Couldn't find segment next to %s in %s\n",
798 old_sbss_index == -1 ? ".sbss" : ".bss", old_name);
800 NEW_PROGRAM_H (n).p_filesz += new_offsets_shift;
801 NEW_PROGRAM_H (n).p_memsz = NEW_PROGRAM_H (n).p_filesz;
803 #if 1 /* Maybe allow section after data2 - does this ever happen? */
804 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
806 if (NEW_PROGRAM_H (n).p_vaddr
807 && NEW_PROGRAM_H (n).p_vaddr >= new_data2_addr)
808 NEW_PROGRAM_H (n).p_vaddr += new_offsets_shift - old_bss_size;
810 if (NEW_PROGRAM_H (n).p_offset >= new_data2_offset)
811 NEW_PROGRAM_H (n).p_offset += new_offsets_shift;
815 /* Fix up section headers based on new .data2 section. Any section
816 whose offset or virtual address is after the new .data2 section
817 gets its value adjusted. .bss size becomes zero and new address
818 is set. data2 section header gets added by copying the existing
819 .data header and modifying the offset, address and size. */
820 for (old_data_index = 1; old_data_index < old_file_h->e_shnum;
822 if (!strcmp (old_section_names + OLD_SECTION_H (old_data_index).sh_name,
825 if (old_data_index == old_file_h->e_shnum)
826 fatal ("Can't find .data in %s.\n", old_name);
828 /* Walk through all section headers, insert the new data2 section right
829 before the new bss section. */
830 for (n = 1, nn = 1; n < old_file_h->e_shnum; n++, nn++)
835 if (n < old_bss_index)
837 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n),
838 old_file_h->e_shentsize);
841 else if (n == old_bss_index)
844 /* If it is bss section, insert the new data2 section before it. */
845 /* Steal the data section header for this data2 section. */
846 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (old_data_index),
847 new_file_h->e_shentsize);
849 NEW_SECTION_H (nn).sh_addr = new_data2_addr;
850 NEW_SECTION_H (nn).sh_offset = new_data2_offset;
851 NEW_SECTION_H (nn).sh_size = new_data2_size;
852 /* Use the bss section's alignment. This will assure that the
853 new data2 section always be placed in the same spot as the old
854 bss section by any other application. */
855 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (n).sh_addralign;
857 /* Now copy over what we have in the memory now. */
858 memcpy (NEW_SECTION_H (nn).sh_offset + new_base,
859 (caddr_t) OLD_SECTION_H (n).sh_addr,
862 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n),
863 old_file_h->e_shentsize);
865 /* The new bss section's size is zero, and its file offset and virtual
866 address should be off by NEW_OFFSETS_SHIFT. */
867 NEW_SECTION_H (nn).sh_offset += new_offsets_shift;
868 NEW_SECTION_H (nn).sh_addr = new_bss_addr;
869 /* Let the new bss section address alignment be the same as the
870 section address alignment followed the old bss section, so
871 this section will be placed in exactly the same place. */
872 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (n).sh_addralign;
873 NEW_SECTION_H (nn).sh_size = 0;
875 else /* n > old_bss_index */
876 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n),
877 old_file_h->e_shentsize);
879 /* Any section that was original placed AFTER the bss
880 section must now be adjusted by NEW_OFFSETS_SHIFT. */
882 if (NEW_SECTION_H (nn).sh_offset >= new_base_offset)
883 NEW_SECTION_H (nn).sh_offset += new_offsets_shift;
885 /* If any section hdr refers to the section after the new .data
886 section, make it refer to next one because we have inserted
887 a new section in between. */
889 PATCH_INDEX (NEW_SECTION_H (nn).sh_link);
890 /* For symbol tables, info is a symbol table index,
891 so don't change it. */
892 if (NEW_SECTION_H (nn).sh_type != SHT_SYMTAB
893 && NEW_SECTION_H (nn).sh_type != SHT_DYNSYM)
894 PATCH_INDEX (NEW_SECTION_H (nn).sh_info);
896 /* Fix the type and alignment for the .sbss section */
897 if ((old_sbss_index != -1) && !strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".sbss"))
899 NEW_SECTION_H (nn).sh_type = SHT_PROGBITS;
900 NEW_SECTION_H (nn).sh_offset = round_up (NEW_SECTION_H (nn).sh_offset,
901 NEW_SECTION_H (nn).sh_addralign);
904 /* Now, start to copy the content of sections. */
905 if (NEW_SECTION_H (nn).sh_type == SHT_NULL
906 || NEW_SECTION_H (nn).sh_type == SHT_NOBITS)
909 /* Write out the sections. .data, .data1 and .sbss (and data2, called
910 ".data" in the strings table) get copied from the current process
911 instead of the old file. */
912 if (!strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".data")
913 || !strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".data1")
914 || !strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".got")
915 || !strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".sbss"))
916 src = (caddr_t) OLD_SECTION_H (n).sh_addr;
918 src = old_base + OLD_SECTION_H (n).sh_offset;
920 memcpy (NEW_SECTION_H (nn).sh_offset + new_base, src,
921 NEW_SECTION_H (nn).sh_size);
923 /* Adjust the HDRR offsets in .mdebug and copy the
924 line data if it's in its usual 'hole' in the object.
925 Makes the new file debuggable with dbx.
926 patches up two problems: the absolute file offsets
927 in the HDRR record of .mdebug (see /usr/include/syms.h), and
928 the ld bug that gets the line table in a hole in the
929 elf file rather than in the .mdebug section proper.
930 David Anderson. davea@sgi.com Jan 16,1994. */
931 if (n == old_mdebug_index)
933 #define MDEBUGADJUST(__ct,__fileaddr) \
934 if (n_phdrr->__ct > 0) \
936 n_phdrr->__fileaddr += movement; \
939 HDRR * o_phdrr = (HDRR *)((byte *)old_base + OLD_SECTION_H (n).sh_offset);
940 HDRR * n_phdrr = (HDRR *)((byte *)new_base + NEW_SECTION_H (nn).sh_offset);
941 unsigned movement = new_offsets_shift;
943 MDEBUGADJUST (idnMax, cbDnOffset);
944 MDEBUGADJUST (ipdMax, cbPdOffset);
945 MDEBUGADJUST (isymMax, cbSymOffset);
946 MDEBUGADJUST (ioptMax, cbOptOffset);
947 MDEBUGADJUST (iauxMax, cbAuxOffset);
948 MDEBUGADJUST (issMax, cbSsOffset);
949 MDEBUGADJUST (issExtMax, cbSsExtOffset);
950 MDEBUGADJUST (ifdMax, cbFdOffset);
951 MDEBUGADJUST (crfd, cbRfdOffset);
952 MDEBUGADJUST (iextMax, cbExtOffset);
953 /* The Line Section, being possible off in a hole of the object,
954 requires special handling. */
955 if (n_phdrr->cbLine > 0)
957 if (o_phdrr->cbLineOffset > (OLD_SECTION_H (n).sh_offset
958 + OLD_SECTION_H (n).sh_size))
960 /* line data is in a hole in elf. do special copy and adjust
963 n_phdrr->cbLineOffset += movement;
965 memcpy (n_phdrr->cbLineOffset + new_base,
966 o_phdrr->cbLineOffset + old_base, n_phdrr->cbLine);
970 /* somehow line data is in .mdebug as it is supposed to be. */
971 MDEBUGADJUST (cbLine, cbLineOffset);
976 /* If it is the symbol table, its st_shndx field needs to be patched. */
977 if (NEW_SECTION_H (nn).sh_type == SHT_SYMTAB
978 || NEW_SECTION_H (nn).sh_type == SHT_DYNSYM)
980 l_Elf_Shdr *spt = &NEW_SECTION_H (nn);
981 unsigned int num = spt->sh_size / spt->sh_entsize;
982 l_Elf_Sym * sym = (l_Elf_Sym *) (NEW_SECTION_H (nn).sh_offset
986 if (sym->st_shndx == SHN_UNDEF
987 || sym->st_shndx == SHN_ABS
988 || sym->st_shndx == SHN_COMMON)
991 PATCH_INDEX (sym->st_shndx);
996 /* Close the files and make the new file executable. */
998 if (close (old_file))
999 fatal ("Can't close (%s): errno %d\n", old_name, errno);
1001 if (close (new_file))
1002 fatal ("Can't close (%s): errno %d\n", new_name, errno);
1004 if (stat (new_name, &stat_buf) == -1)
1005 fatal ("Can't stat (%s): errno %d\n", new_name, errno);
1009 stat_buf.st_mode |= 0111 & ~n;
1010 if (chmod (new_name, stat_buf.st_mode) == -1)
1011 fatal ("Can't chmod (%s): errno %d\n", new_name, errno);