1 /* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992
2 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 2, or (at your option)
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; 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 In other words, you are welcome to use, share and improve this program.
22 You are forbidden to forbid anyone else to use, share and improve
23 what you give them. Help stamp out software-hoarding! */
27 * unexec.c - Convert a running program into an a.out file.
29 * Author: Spencer W. Thomas
30 * Computer Science Dept.
32 * Date: Tue Mar 2 1982
33 * Modified heavily since then.
36 * unexec (new_name, a_name, data_start, bss_start, entry_address)
37 * char *new_name, *a_name;
38 * unsigned data_start, bss_start, entry_address;
40 * Takes a snapshot of the program and makes an a.out format file in the
41 * file named by the string argument new_name.
42 * If a_name is non-NULL, the symbol table will be taken from the given file.
43 * On some machines, an existing a_name file is required.
45 * The boundaries within the a.out file may be adjusted with the data_start
46 * and bss_start arguments. Either or both may be given as 0 for defaults.
48 * Data_start gives the boundary between the text segment and the data
49 * segment of the program. The text segment can contain shared, read-only
50 * program code and literal data, while the data segment is always unshared
51 * and unprotected. Data_start gives the lowest unprotected address.
52 * The value you specify may be rounded down to a suitable boundary
53 * as required by the machine you are using.
55 * Specifying zero for data_start means the boundary between text and data
56 * should not be the same as when the program was loaded.
57 * If NO_REMAP is defined, the argument data_start is ignored and the
58 * segment boundaries are never changed.
60 * Bss_start indicates how much of the data segment is to be saved in the
61 * a.out file and restored when the program is executed. It gives the lowest
62 * unsaved address, and is rounded up to a page boundary. The default when 0
63 * is given assumes that the entire data segment is to be stored, including
64 * the previous data and bss as well as any additional storage allocated with
67 * The new file is set up to start at entry_address.
69 * If you make improvements I'd like to get them too.
70 * harpo!utah-cs!thomas, thomas@Utah-20
74 /* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
77 * Basic theory: the data space of the running process needs to be
78 * dumped to the output file. Normally we would just enlarge the size
79 * of .data, scooting everything down. But we can't do that in ELF,
80 * because there is often something between the .data space and the
83 * In the temacs dump below, notice that the Global Offset Table
84 * (.got) and the Dynamic link data (.dynamic) come between .data1 and
85 * .bss. It does not work to overlap .data with these fields.
87 * The solution is to create a new .data segment. This segment is
88 * filled with data from the current process. Since the contents of
89 * various sections refer to sections by index, the new .data segment
90 * is made the last in the table to avoid changing any existing index.
92 * This is an example of how the section headers are changed. "Addr"
93 * is a process virtual address. "Offset" is a file offset.
95 raid:/nfs/raid/src/dist-18.56/src> dump -h temacs
99 **** SECTION HEADER TABLE ****
100 [No] Type Flags Addr Offset Size Name
101 Link Info Adralgn Entsize
103 [1] 1 2 0x80480d4 0xd4 0x13 .interp
106 [2] 5 2 0x80480e8 0xe8 0x388 .hash
109 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
112 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
115 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
118 [6] 1 6 0x8049348 0x1348 0x3 .init
121 [7] 1 6 0x804934c 0x134c 0x680 .plt
124 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
127 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
130 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
133 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
136 [12] 1 3 0x8088330 0x3f330 0x20afc .data
139 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
142 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
145 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
148 [16] 8 3 0x80a98f4 0x608f4 0x449c .bss
151 [17] 2 0 0 0x608f4 0x9b90 .symtab
154 [18] 3 0 0 0x6a484 0x8526 .strtab
157 [19] 3 0 0 0x729aa 0x93 .shstrtab
160 [20] 1 0 0 0x72a3d 0x68b7 .comment
163 raid:/nfs/raid/src/dist-18.56/src> dump -h xemacs
167 **** SECTION HEADER TABLE ****
168 [No] Type Flags Addr Offset Size Name
169 Link Info Adralgn Entsize
171 [1] 1 2 0x80480d4 0xd4 0x13 .interp
174 [2] 5 2 0x80480e8 0xe8 0x388 .hash
177 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
180 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
183 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
186 [6] 1 6 0x8049348 0x1348 0x3 .init
189 [7] 1 6 0x804934c 0x134c 0x680 .plt
192 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
195 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
198 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
201 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
204 [12] 1 3 0x8088330 0x3f330 0x20afc .data
207 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
210 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
213 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
216 [16] 8 3 0x80c6800 0x7d800 0 .bss
219 [17] 2 0 0 0x7d800 0x9b90 .symtab
222 [18] 3 0 0 0x87390 0x8526 .strtab
225 [19] 3 0 0 0x8f8b6 0x93 .shstrtab
228 [20] 1 0 0 0x8f949 0x68b7 .comment
231 [21] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
234 * This is an example of how the file header is changed. "Shoff" is
235 * the section header offset within the file. Since that table is
236 * after the new .data section, it is moved. "Shnum" is the number of
237 * sections, which we increment.
239 * "Phoff" is the file offset to the program header. "Phentsize" and
240 * "Shentsz" are the program and section header entries sizes respectively.
241 * These can be larger than the apparent struct sizes.
243 raid:/nfs/raid/src/dist-18.56/src> dump -f temacs
248 Class Data Type Machine Version
249 Entry Phoff Shoff Flags Ehsize
250 Phentsize Phnum Shentsz Shnum Shstrndx
253 0x80499cc 0x34 0x792f4 0 0x34
256 raid:/nfs/raid/src/dist-18.56/src> dump -f xemacs
261 Class Data Type Machine Version
262 Entry Phoff Shoff Flags Ehsize
263 Phentsize Phnum Shentsz Shnum Shstrndx
266 0x80499cc 0x34 0x96200 0 0x34
269 * These are the program headers. "Offset" is the file offset to the
270 * segment. "Vaddr" is the memory load address. "Filesz" is the
271 * segment size as it appears in the file, and "Memsz" is the size in
272 * memory. Below, the third segment is the code and the fourth is the
273 * data: the difference between Filesz and Memsz is .bss
275 raid:/nfs/raid/src/dist-18.56/src> dump -o temacs
278 ***** PROGRAM EXECUTION HEADER *****
279 Type Offset Vaddr Paddr
280 Filesz Memsz Flags Align
289 0x3f2f9 0x3f2f9 5 0x1000
291 1 0x3f330 0x8088330 0
292 0x215c4 0x25a60 7 0x1000
294 2 0x60874 0x80a9874 0
297 raid:/nfs/raid/src/dist-18.56/src> dump -o xemacs
300 ***** PROGRAM EXECUTION HEADER *****
301 Type Offset Vaddr Paddr
302 Filesz Memsz Flags Align
311 0x3f2f9 0x3f2f9 5 0x1000
313 1 0x3f330 0x8088330 0
314 0x3e4d0 0x3e4d0 7 0x1000
316 2 0x60874 0x80a9874 0
322 /* Modified by wtien@urbana.mcd.mot.com of Motorola Inc.
324 * The above mechanism does not work if the unexeced ELF file is being
325 * re-layout by other applications (such as `strip'). All the applications
326 * that re-layout the internal of ELF will layout all sections in ascending
327 * order of their file offsets. After the re-layout, the data2 section will
328 * still be the LAST section in the section header vector, but its file offset
329 * is now being pushed far away down, and causes part of it not to be mapped
330 * in (ie. not covered by the load segment entry in PHDR vector), therefore
331 * causes the new binary to fail.
333 * The solution is to modify the unexec algorithm to insert the new data2
334 * section header right before the new bss section header, so their file
335 * offsets will be in the ascending order. Since some of the section's (all
336 * sections AFTER the bss section) indexes are now changed, we also need to
337 * modify some fields to make them point to the right sections. This is done
338 * by macro PATCH_INDEX. All the fields that need to be patched are:
340 * 1. ELF header e_shstrndx field.
341 * 2. section header sh_link and sh_info field.
342 * 3. symbol table entry st_shndx field.
344 * The above example now should look like:
346 **** SECTION HEADER TABLE ****
347 [No] Type Flags Addr Offset Size Name
348 Link Info Adralgn Entsize
350 [1] 1 2 0x80480d4 0xd4 0x13 .interp
353 [2] 5 2 0x80480e8 0xe8 0x388 .hash
356 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
359 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
362 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
365 [6] 1 6 0x8049348 0x1348 0x3 .init
368 [7] 1 6 0x804934c 0x134c 0x680 .plt
371 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
374 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
377 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
380 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
383 [12] 1 3 0x8088330 0x3f330 0x20afc .data
386 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
389 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
392 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
395 [16] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
398 [17] 8 3 0x80c6800 0x7d800 0 .bss
401 [18] 2 0 0 0x7d800 0x9b90 .symtab
404 [19] 3 0 0 0x87390 0x8526 .strtab
407 [20] 3 0 0 0x8f8b6 0x93 .shstrtab
410 [21] 1 0 0 0x8f949 0x68b7 .comment
415 #include <sys/types.h>
417 #include <sys/stat.h>
424 #include <sys/mman.h>
427 # include <sym.h> /* get COFF debugging symbol table declaration */
430 #ifdef __GNU_LIBRARY__
431 # include <link.h> /* get definition of ElfW */
436 # define ElfW(type) Elf32_##type
438 # define ElfW(type) Elf32_/**/type
443 #define fatal(a, b, c) fprintf (stderr, a, b, c), exit (1)
446 extern void fatal (char *, ...);
449 #ifndef ELF_BSS_SECTION_NAME
450 #define ELF_BSS_SECTION_NAME ".bss"
453 /* Get the address of a particular section or program header entry,
454 * accounting for the size of the entries.
457 On PPC Reference Platform running Solaris 2.5.1
458 the plt section is also of type NOBI like the bss section.
459 (not really stored) and therefore sections after the bss
460 section start at the plt offset. The plt section is always
461 the one just before the bss section.
462 Thus, we modify the test from
463 if (NEW_SECTION_H (nn).sh_offset >= new_data2_offset)
465 if (NEW_SECTION_H (nn).sh_offset >=
466 OLD_SECTION_H (old_bss_index-1).sh_offset)
467 This is just a hack. We should put the new data section
468 before the .plt section.
469 And we should not have this routine at all but use
470 the libelf library to read the old file and create the new
472 The changed code is minimal and depends on prep set in m/prep.h
474 Quantum Theory Project
475 University of Florida
480 #define OLD_SECTION_H(n) \
481 (*(ElfW(Shdr) *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
482 #define NEW_SECTION_H(n) \
483 (*(ElfW(Shdr) *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
484 #define OLD_PROGRAM_H(n) \
485 (*(ElfW(Phdr) *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
486 #define NEW_PROGRAM_H(n) \
487 (*(ElfW(Phdr) *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
489 #define PATCH_INDEX(n) \
491 if ((int) (n) >= old_bss_index) \
493 typedef unsigned char byte
;
495 /* Round X up to a multiple of Y. */
507 /* ****************************************************************
512 * In ELF, this works by replacing the old .bss section with a new
513 * .data section, and inserting an empty .bss immediately afterwards.
517 unexec (new_name
, old_name
, data_start
, bss_start
, entry_address
)
518 char *new_name
, *old_name
;
519 unsigned data_start
, bss_start
, entry_address
;
521 int new_file
, old_file
, new_file_size
;
523 /* Pointers to the base of the image of the two files. */
524 caddr_t old_base
, new_base
;
526 /* Pointers to the file, program and section headers for the old and new
529 ElfW(Ehdr
) *old_file_h
, *new_file_h
;
530 ElfW(Phdr
) *old_program_h
, *new_program_h
;
531 ElfW(Shdr
) *old_section_h
, *new_section_h
;
533 /* Point to the section name table in the old file */
534 char *old_section_names
;
536 ElfW(Addr
) old_bss_addr
, new_bss_addr
;
537 ElfW(Addr
) old_bss_size
, new_data2_size
;
538 ElfW(Off
) new_data2_offset
;
539 ElfW(Addr
) new_data2_addr
;
541 int n
, nn
, old_bss_index
, old_data_index
;
542 struct stat stat_buf
;
544 /* Open the old file & map it into the address space. */
546 old_file
= open (old_name
, O_RDONLY
);
549 fatal ("Can't open %s for reading: errno %d\n", old_name
, errno
);
551 if (fstat (old_file
, &stat_buf
) == -1)
552 fatal ("Can't fstat (%s): errno %d\n", old_name
, errno
);
554 old_base
= mmap (0, stat_buf
.st_size
, PROT_READ
, MAP_SHARED
, old_file
, 0);
556 if (old_base
== (caddr_t
) -1)
557 fatal ("Can't mmap (%s): errno %d\n", old_name
, errno
);
560 fprintf (stderr
, "mmap (%s, %lx) -> %lx\n", old_name
, stat_buf
.st_size
,
561 (unsigned long) old_base
);
564 /* Get pointers to headers & section names */
566 old_file_h
= (ElfW(Ehdr
) *) old_base
;
567 old_program_h
= (ElfW(Phdr
) *) ((byte
*) old_base
+ old_file_h
->e_phoff
);
568 old_section_h
= (ElfW(Shdr
) *) ((byte
*) old_base
+ old_file_h
->e_shoff
);
569 old_section_names
= (char *) old_base
570 + OLD_SECTION_H (old_file_h
->e_shstrndx
).sh_offset
;
572 /* Find the old .bss section. Figure out parameters of the new
573 * data2 and bss sections.
576 for (old_bss_index
= 1; old_bss_index
< (int) old_file_h
->e_shnum
;
580 fprintf (stderr
, "Looking for .bss - found %s\n",
581 old_section_names
+ OLD_SECTION_H (old_bss_index
).sh_name
);
583 if (!strcmp (old_section_names
+ OLD_SECTION_H (old_bss_index
).sh_name
,
584 ELF_BSS_SECTION_NAME
))
587 if (old_bss_index
== old_file_h
->e_shnum
)
588 fatal ("Can't find .bss in %s.\n", old_name
, 0);
590 old_bss_addr
= OLD_SECTION_H (old_bss_index
).sh_addr
;
591 old_bss_size
= OLD_SECTION_H (old_bss_index
).sh_size
;
592 #if defined(emacs) || !defined(DEBUG)
593 new_bss_addr
= (ElfW(Addr
)) sbrk (0);
595 new_bss_addr
= old_bss_addr
+ old_bss_size
+ 0x1234;
597 new_data2_addr
= old_bss_addr
;
598 new_data2_size
= new_bss_addr
- old_bss_addr
;
599 new_data2_offset
= OLD_SECTION_H (old_bss_index
).sh_offset
;
602 fprintf (stderr
, "old_bss_index %d\n", old_bss_index
);
603 fprintf (stderr
, "old_bss_addr %lx\n", old_bss_addr
);
604 fprintf (stderr
, "old_bss_size %lx\n", old_bss_size
);
605 fprintf (stderr
, "new_bss_addr %lx\n", new_bss_addr
);
606 fprintf (stderr
, "new_data2_addr %lx\n", new_data2_addr
);
607 fprintf (stderr
, "new_data2_size %lx\n", new_data2_size
);
608 fprintf (stderr
, "new_data2_offset %lx\n", new_data2_offset
);
611 if ((unsigned long) new_bss_addr
612 < (unsigned long) old_bss_addr
+ old_bss_size
)
613 fatal (".bss shrank when undumping???\n", 0, 0);
615 /* Set the output file to the right size and mmap it. Set
616 * pointers to various interesting objects. stat_buf still has
620 new_file
= open (new_name
, O_RDWR
| O_CREAT
, 0666);
622 fatal ("Can't creat (%s): errno %d\n", new_name
, errno
);
624 new_file_size
= stat_buf
.st_size
+ old_file_h
->e_shentsize
+ new_data2_size
;
626 if (ftruncate (new_file
, new_file_size
))
627 fatal ("Can't ftruncate (%s): errno %d\n", new_name
, errno
);
629 #ifdef UNEXEC_USE_MAP_PRIVATE
630 new_base
= mmap (0, new_file_size
, PROT_READ
| PROT_WRITE
, MAP_PRIVATE
,
633 new_base
= mmap (0, new_file_size
, PROT_READ
| PROT_WRITE
, MAP_SHARED
,
637 if (new_base
== (caddr_t
) -1)
638 fatal ("Can't mmap (%s): errno %d\n", new_name
, errno
);
640 new_file_h
= (ElfW(Ehdr
) *) new_base
;
641 new_program_h
= (ElfW(Phdr
) *) ((byte
*) new_base
+ old_file_h
->e_phoff
);
642 new_section_h
= (ElfW(Shdr
) *)
643 ((byte
*) new_base
+ old_file_h
->e_shoff
+ new_data2_size
);
645 /* Make our new file, program and section headers as copies of the
649 memcpy (new_file_h
, old_file_h
, old_file_h
->e_ehsize
);
650 memcpy (new_program_h
, old_program_h
,
651 old_file_h
->e_phnum
* old_file_h
->e_phentsize
);
653 /* Modify the e_shstrndx if necessary. */
654 PATCH_INDEX (new_file_h
->e_shstrndx
);
656 /* Fix up file header. We'll add one section. Section header is
660 new_file_h
->e_shoff
+= new_data2_size
;
661 new_file_h
->e_shnum
+= 1;
664 fprintf (stderr
, "Old section offset %lx\n", old_file_h
->e_shoff
);
665 fprintf (stderr
, "Old section count %d\n", old_file_h
->e_shnum
);
666 fprintf (stderr
, "New section offset %lx\n", new_file_h
->e_shoff
);
667 fprintf (stderr
, "New section count %d\n", new_file_h
->e_shnum
);
670 /* Fix up a new program header. Extend the writable data segment so
671 * that the bss area is covered too. Find that segment by looking
672 * for a segment that ends just before the .bss area. Make sure
673 * that no segments are above the new .data2. Put a loop at the end
674 * to adjust the offset and address of any segment that is above
675 * data2, just in case we decide to allow this later.
678 for (n
= new_file_h
->e_phnum
- 1; n
>= 0; n
--)
680 /* Compute maximum of all requirements for alignment of section. */
681 unsigned int alignment
= (NEW_PROGRAM_H (n
)).p_align
;
682 if ((OLD_SECTION_H (old_bss_index
)).sh_addralign
> alignment
)
683 alignment
= OLD_SECTION_H (old_bss_index
).sh_addralign
;
685 if (NEW_PROGRAM_H (n
).p_vaddr
+ NEW_PROGRAM_H (n
).p_filesz
> old_bss_addr
)
686 fatal ("Program segment above .bss in %s\n", old_name
, 0);
688 if (NEW_PROGRAM_H (n
).p_type
== PT_LOAD
689 && (round_up ((NEW_PROGRAM_H (n
)).p_vaddr
690 + (NEW_PROGRAM_H (n
)).p_filesz
,
692 == round_up (old_bss_addr
, alignment
)))
696 fatal ("Couldn't find segment next to .bss in %s\n", old_name
, 0);
698 NEW_PROGRAM_H (n
).p_filesz
+= new_data2_size
;
699 NEW_PROGRAM_H (n
).p_memsz
= NEW_PROGRAM_H (n
).p_filesz
;
701 #if 0 /* Maybe allow section after data2 - does this ever happen? */
702 for (n
= new_file_h
->e_phnum
- 1; n
>= 0; n
--)
704 if (NEW_PROGRAM_H (n
).p_vaddr
705 && NEW_PROGRAM_H (n
).p_vaddr
>= new_data2_addr
)
706 NEW_PROGRAM_H (n
).p_vaddr
+= new_data2_size
- old_bss_size
;
708 if (NEW_PROGRAM_H (n
).p_offset
>= new_data2_offset
)
709 NEW_PROGRAM_H (n
).p_offset
+= new_data2_size
;
713 /* Fix up section headers based on new .data2 section. Any section
714 * whose offset or virtual address is after the new .data2 section
715 * gets its value adjusted. .bss size becomes zero and new address
716 * is set. data2 section header gets added by copying the existing
717 * .data header and modifying the offset, address and size.
719 for (old_data_index
= 1; old_data_index
< (int) old_file_h
->e_shnum
;
721 if (!strcmp (old_section_names
+ OLD_SECTION_H (old_data_index
).sh_name
,
724 if (old_data_index
== old_file_h
->e_shnum
)
725 fatal ("Can't find .data in %s.\n", old_name
, 0);
727 /* Walk through all section headers, insert the new data2 section right
728 before the new bss section. */
729 for (n
= 1, nn
= 1; n
< (int) old_file_h
->e_shnum
; n
++, nn
++)
732 /* If it is bss section, insert the new data2 section before it. */
733 if (n
== old_bss_index
)
735 /* Steal the data section header for this data2 section. */
736 memcpy (&NEW_SECTION_H (nn
), &OLD_SECTION_H (old_data_index
),
737 new_file_h
->e_shentsize
);
739 NEW_SECTION_H (nn
).sh_addr
= new_data2_addr
;
740 NEW_SECTION_H (nn
).sh_offset
= new_data2_offset
;
741 NEW_SECTION_H (nn
).sh_size
= new_data2_size
;
742 /* Use the bss section's alignment. This will assure that the
743 new data2 section always be placed in the same spot as the old
744 bss section by any other application. */
745 NEW_SECTION_H (nn
).sh_addralign
= OLD_SECTION_H (n
).sh_addralign
;
747 /* Now copy over what we have in the memory now. */
748 memcpy (NEW_SECTION_H (nn
).sh_offset
+ new_base
,
749 (caddr_t
) OLD_SECTION_H (n
).sh_addr
,
754 memcpy (&NEW_SECTION_H (nn
), &OLD_SECTION_H (n
),
755 old_file_h
->e_shentsize
);
757 /* The new bss section's size is zero, and its file offset and virtual
758 address should be off by NEW_DATA2_SIZE. */
759 if (n
== old_bss_index
)
761 /* NN should be `old_bss_index + 1' at this point. */
762 NEW_SECTION_H (nn
).sh_offset
+= new_data2_size
;
763 NEW_SECTION_H (nn
).sh_addr
+= new_data2_size
;
764 /* Let the new bss section address alignment be the same as the
765 section address alignment followed the old bss section, so
766 this section will be placed in exactly the same place. */
767 NEW_SECTION_H (nn
).sh_addralign
= OLD_SECTION_H (nn
).sh_addralign
;
768 NEW_SECTION_H (nn
).sh_size
= 0;
772 /* Any section that was original placed AFTER the bss
773 section should now be off by NEW_DATA2_SIZE. */
774 #ifdef SOLARIS_POWERPC
775 /* On PPC Reference Platform running Solaris 2.5.1
776 the plt section is also of type NOBI like the bss section.
777 (not really stored) and therefore sections after the bss
778 section start at the plt offset. The plt section is always
779 the one just before the bss section.
780 It would be better to put the new data section before
781 the .plt section, or use libelf instead.
782 Erik Deumens, deumens@qtp.ufl.edu. */
783 if (NEW_SECTION_H (nn
).sh_offset
784 >= OLD_SECTION_H (old_bss_index
-1).sh_offset
)
785 NEW_SECTION_H (nn
).sh_offset
+= new_data2_size
;
787 if (round_up (NEW_SECTION_H (nn
).sh_offset
,
788 OLD_SECTION_H (old_bss_index
).sh_addralign
)
790 NEW_SECTION_H (nn
).sh_offset
+= new_data2_size
;
792 /* Any section that was originally placed after the section
793 header table should now be off by the size of one section
794 header table entry. */
795 if (NEW_SECTION_H (nn
).sh_offset
> new_file_h
->e_shoff
)
796 NEW_SECTION_H (nn
).sh_offset
+= new_file_h
->e_shentsize
;
799 /* If any section hdr refers to the section after the new .data
800 section, make it refer to next one because we have inserted
801 a new section in between. */
803 PATCH_INDEX (NEW_SECTION_H (nn
).sh_link
);
804 /* For symbol tables, info is a symbol table index,
805 so don't change it. */
806 if (NEW_SECTION_H (nn
).sh_type
!= SHT_SYMTAB
807 && NEW_SECTION_H (nn
).sh_type
!= SHT_DYNSYM
)
808 PATCH_INDEX (NEW_SECTION_H (nn
).sh_info
);
810 /* Now, start to copy the content of sections. */
811 if (NEW_SECTION_H (nn
).sh_type
== SHT_NULL
812 || NEW_SECTION_H (nn
).sh_type
== SHT_NOBITS
)
815 /* Write out the sections. .data and .data1 (and data2, called
816 ".data" in the strings table) get copied from the current process
817 instead of the old file. */
818 if (!strcmp (old_section_names
+ NEW_SECTION_H (n
).sh_name
, ".data")
819 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
821 src
= (caddr_t
) OLD_SECTION_H (n
).sh_addr
;
823 src
= old_base
+ OLD_SECTION_H (n
).sh_offset
;
825 memcpy (NEW_SECTION_H (nn
).sh_offset
+ new_base
, src
,
826 NEW_SECTION_H (nn
).sh_size
);
829 /* Update Alpha COFF symbol table: */
830 if (strcmp (old_section_names
+ OLD_SECTION_H (n
).sh_name
, ".mdebug")
833 pHDRR symhdr
= (pHDRR
) (NEW_SECTION_H (nn
).sh_offset
+ new_base
);
835 symhdr
->cbLineOffset
+= new_data2_size
;
836 symhdr
->cbDnOffset
+= new_data2_size
;
837 symhdr
->cbPdOffset
+= new_data2_size
;
838 symhdr
->cbSymOffset
+= new_data2_size
;
839 symhdr
->cbOptOffset
+= new_data2_size
;
840 symhdr
->cbAuxOffset
+= new_data2_size
;
841 symhdr
->cbSsOffset
+= new_data2_size
;
842 symhdr
->cbSsExtOffset
+= new_data2_size
;
843 symhdr
->cbFdOffset
+= new_data2_size
;
844 symhdr
->cbRfdOffset
+= new_data2_size
;
845 symhdr
->cbExtOffset
+= new_data2_size
;
847 #endif /* __alpha__ */
849 /* If it is the symbol table, its st_shndx field needs to be patched. */
850 if (NEW_SECTION_H (nn
).sh_type
== SHT_SYMTAB
851 || NEW_SECTION_H (nn
).sh_type
== SHT_DYNSYM
)
853 ElfW(Shdr
) *spt
= &NEW_SECTION_H (nn
);
854 unsigned int num
= spt
->sh_size
/ spt
->sh_entsize
;
855 ElfW(Sym
) * sym
= (ElfW(Sym
) *) (NEW_SECTION_H (nn
).sh_offset
+
859 if ((sym
->st_shndx
== SHN_UNDEF
)
860 || (sym
->st_shndx
== SHN_ABS
)
861 || (sym
->st_shndx
== SHN_COMMON
))
864 PATCH_INDEX (sym
->st_shndx
);
869 /* Update the symbol values of _edata and _end. */
870 for (n
= new_file_h
->e_shnum
- 1; n
; n
--)
873 ElfW(Sym
) *symp
, *symendp
;
875 if (NEW_SECTION_H (n
).sh_type
!= SHT_DYNSYM
876 && NEW_SECTION_H (n
).sh_type
!= SHT_SYMTAB
)
879 symnames
= ((byte
*) new_base
880 + NEW_SECTION_H (NEW_SECTION_H (n
).sh_link
).sh_offset
);
881 symp
= (ElfW(Sym
) *) (NEW_SECTION_H (n
).sh_offset
+ new_base
);
882 symendp
= (ElfW(Sym
) *) ((byte
*)symp
+ NEW_SECTION_H (n
).sh_size
);
884 for (; symp
< symendp
; symp
++)
885 if (strcmp ((char *) (symnames
+ symp
->st_name
), "_end") == 0
886 || strcmp ((char *) (symnames
+ symp
->st_name
), "_edata") == 0)
887 memcpy (&symp
->st_value
, &new_bss_addr
, sizeof (new_bss_addr
));
890 /* This loop seeks out relocation sections for the data section, so
891 that it can undo relocations performed by the runtime linker. */
892 for (n
= new_file_h
->e_shnum
- 1; n
; n
--)
894 ElfW(Shdr
) section
= NEW_SECTION_H (n
);
895 switch (section
.sh_type
) {
900 /* This code handles two different size structs, but there should
901 be no harm in that provided that r_offset is always the first
903 nn
= section
.sh_info
;
904 if (!strcmp (old_section_names
+ NEW_SECTION_H (nn
).sh_name
, ".data")
905 || !strcmp ((old_section_names
+ NEW_SECTION_H (nn
).sh_name
),
908 ElfW(Addr
) offset
= NEW_SECTION_H (nn
).sh_addr
-
909 NEW_SECTION_H (nn
).sh_offset
;
910 caddr_t reloc
= old_base
+ section
.sh_offset
, end
;
911 for (end
= reloc
+ section
.sh_size
; reloc
< end
;
912 reloc
+= section
.sh_entsize
)
916 /* The Alpha ELF binutils currently have a bug that
917 sometimes results in relocs that contain all
918 zeroes. Work around this for now... */
919 if (((ElfW(Rel
) *) reloc
)->r_offset
== 0)
922 addr
= ((ElfW(Rel
) *) reloc
)->r_offset
- offset
;
923 memcpy (new_base
+ addr
, old_base
+ addr
, sizeof(ElfW(Addr
)));
930 #ifdef UNEXEC_USE_MAP_PRIVATE
931 if (lseek (new_file
, 0, SEEK_SET
) == -1)
932 fatal ("Can't rewind (%s): errno %d\n", new_name
, errno
);
934 if (write (new_file
, new_base
, new_file_size
) != new_file_size
)
935 fatal ("Can't write (%s): errno %d\n", new_name
, errno
);
938 /* Close the files and make the new file executable. */
940 if (close (old_file
))
941 fatal ("Can't close (%s): errno %d\n", old_name
, errno
);
943 if (close (new_file
))
944 fatal ("Can't close (%s): errno %d\n", new_name
, errno
);
946 if (stat (new_name
, &stat_buf
) == -1)
947 fatal ("Can't stat (%s): errno %d\n", new_name
, errno
);
951 stat_buf
.st_mode
|= 0111 & ~n
;
952 if (chmod (new_name
, stat_buf
.st_mode
) == -1)
953 fatal ("Can't chmod (%s): errno %d\n", new_name
, errno
);