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, old_name, data_start, bss_start, entry_address)
37 * char *new_name, *old_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 old_name is non-NULL, the symbol table will be taken from the given file.
43 * On some machines, an existing old_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>
423 #if !defined (__NetBSD__) && !defined (__OpenBSD__)
426 #include <sys/mman.h>
427 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
428 #include <sys/elf_mips.h>
430 #endif /* __sony_news && _SYSTYPE_SYSV */
432 #if defined (__alpha__) && !defined (__NetBSD__) && !defined (__OpenBSD__)
433 /* Declare COFF debugging symbol table. This used to be in
434 /usr/include/sym.h, but this file is no longer included in Red Hat
435 5.0 and presumably in any other glibc 2.x based distribution. */
463 #define cbHDRR sizeof(HDRR)
464 #define hdrNil ((pHDRR)0)
469 * NetBSD does not have normal-looking user-land ELF support.
476 # include <sys/exec_elf.h>
478 # define PT_LOAD Elf_pt_load
479 # define SHT_SYMTAB Elf_sht_symtab
480 # define SHT_DYNSYM Elf_sht_dynsym
481 # define SHT_NULL Elf_sht_null
482 # define SHT_NOBITS Elf_sht_nobits
483 # define SHT_REL Elf_sht_rel
484 # define SHT_RELA Elf_sht_rela
486 # define SHN_UNDEF Elf_eshn_undefined
487 # define SHN_ABS Elf_eshn_absolute
488 # define SHN_COMMON Elf_eshn_common
491 * The magic of picking the right size types is handled by the ELFSIZE
495 # define ElfW(type) Elf_##type
497 # define ElfW(type) Elf_/**/type
501 # include <sys/exec_ecoff.h>
502 # define HDRR struct ecoff_symhdr
503 # define pHDRR HDRR *
505 #endif /* __NetBSD__ */
508 # include <sys/exec_elf.h>
511 #if __GNU_LIBRARY__ - 0 >= 6
512 # include <link.h> /* get ElfW etc */
517 # define ElfW(type) Elf32_##type
519 # define ElfW(type) Elf32_/**/type
524 #define fatal(a, b, c) fprintf (stderr, a, b, c), exit (1)
527 extern void fatal (char *, ...);
530 #ifndef ELF_BSS_SECTION_NAME
531 #define ELF_BSS_SECTION_NAME ".bss"
534 /* Get the address of a particular section or program header entry,
535 * accounting for the size of the entries.
538 On PPC Reference Platform running Solaris 2.5.1
539 the plt section is also of type NOBI like the bss section.
540 (not really stored) and therefore sections after the bss
541 section start at the plt offset. The plt section is always
542 the one just before the bss section.
543 Thus, we modify the test from
544 if (NEW_SECTION_H (nn).sh_offset >= new_data2_offset)
546 if (NEW_SECTION_H (nn).sh_offset >=
547 OLD_SECTION_H (old_bss_index-1).sh_offset)
548 This is just a hack. We should put the new data section
549 before the .plt section.
550 And we should not have this routine at all but use
551 the libelf library to read the old file and create the new
553 The changed code is minimal and depends on prep set in m/prep.h
555 Quantum Theory Project
556 University of Florida
561 #define OLD_SECTION_H(n) \
562 (*(ElfW(Shdr) *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
563 #define NEW_SECTION_H(n) \
564 (*(ElfW(Shdr) *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
565 #define OLD_PROGRAM_H(n) \
566 (*(ElfW(Phdr) *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
567 #define NEW_PROGRAM_H(n) \
568 (*(ElfW(Phdr) *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
570 #define PATCH_INDEX(n) \
572 if ((int) (n) >= old_bss_index) \
574 typedef unsigned char byte
;
576 /* Round X up to a multiple of Y. */
588 /* ****************************************************************
593 * In ELF, this works by replacing the old .bss section with a new
594 * .data section, and inserting an empty .bss immediately afterwards.
598 unexec (new_name
, old_name
, data_start
, bss_start
, entry_address
)
599 char *new_name
, *old_name
;
600 unsigned data_start
, bss_start
, entry_address
;
602 int new_file
, old_file
, new_file_size
;
604 /* Pointers to the base of the image of the two files. */
605 caddr_t old_base
, new_base
;
607 /* Pointers to the file, program and section headers for the old and new
610 ElfW(Ehdr
) *old_file_h
, *new_file_h
;
611 ElfW(Phdr
) *old_program_h
, *new_program_h
;
612 ElfW(Shdr
) *old_section_h
, *new_section_h
;
614 /* Point to the section name table in the old file */
615 char *old_section_names
;
617 ElfW(Addr
) old_bss_addr
, new_bss_addr
;
618 ElfW(Word
) old_bss_size
, new_data2_size
;
619 ElfW(Off
) new_data2_offset
;
620 ElfW(Addr
) new_data2_addr
;
622 int n
, nn
, old_bss_index
, old_data_index
, new_data2_index
;
623 #if defined ( __sony_news) && defined (_SYSTYPE_SYSV)
624 int old_sbss_index
, old_mdebug_index
;
625 #endif /* __sony_news && _SYSTYPE_SYSV */
626 struct stat stat_buf
;
628 /* Open the old file & map it into the address space. */
630 old_file
= open (old_name
, O_RDONLY
);
633 fatal ("Can't open %s for reading: errno %d\n", old_name
, errno
);
635 if (fstat (old_file
, &stat_buf
) == -1)
636 fatal ("Can't fstat (%s): errno %d\n", old_name
, errno
);
638 old_base
= mmap ((caddr_t
) 0, stat_buf
.st_size
, PROT_READ
, MAP_SHARED
,
641 if (old_base
== (caddr_t
) -1)
642 fatal ("Can't mmap (%s): errno %d\n", old_name
, errno
);
645 fprintf (stderr
, "mmap (%s, %x) -> %x\n", old_name
, stat_buf
.st_size
,
649 /* Get pointers to headers & section names */
651 old_file_h
= (ElfW(Ehdr
) *) old_base
;
652 old_program_h
= (ElfW(Phdr
) *) ((byte
*) old_base
+ old_file_h
->e_phoff
);
653 old_section_h
= (ElfW(Shdr
) *) ((byte
*) old_base
+ old_file_h
->e_shoff
);
654 old_section_names
= (char *) old_base
655 + OLD_SECTION_H (old_file_h
->e_shstrndx
).sh_offset
;
657 /* Find the old .bss section. Figure out parameters of the new
658 * data2 and bss sections.
661 for (old_bss_index
= 1; old_bss_index
< (int) old_file_h
->e_shnum
;
665 fprintf (stderr
, "Looking for .bss - found %s\n",
666 old_section_names
+ OLD_SECTION_H (old_bss_index
).sh_name
);
668 if (!strcmp (old_section_names
+ OLD_SECTION_H (old_bss_index
).sh_name
,
669 ELF_BSS_SECTION_NAME
))
672 if (old_bss_index
== old_file_h
->e_shnum
)
673 fatal ("Can't find .bss in %s.\n", old_name
, 0);
675 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
676 for (old_sbss_index
= 1; old_sbss_index
< (int) old_file_h
->e_shnum
;
680 fprintf (stderr
, "Looking for .sbss - found %s\n",
681 old_section_names
+ OLD_SECTION_H (old_sbss_index
).sh_name
);
683 if (!strcmp (old_section_names
+ OLD_SECTION_H (old_sbss_index
).sh_name
,
687 if (old_sbss_index
== old_file_h
->e_shnum
)
689 old_bss_addr
= OLD_SECTION_H(old_bss_index
).sh_addr
;
690 old_bss_size
= OLD_SECTION_H(old_bss_index
).sh_size
;
691 new_data2_offset
= OLD_SECTION_H(old_bss_index
).sh_offset
;
692 new_data2_index
= old_bss_index
;
696 old_bss_addr
= OLD_SECTION_H(old_sbss_index
).sh_addr
;
697 old_bss_size
= OLD_SECTION_H(old_bss_index
).sh_size
698 + OLD_SECTION_H(old_sbss_index
).sh_size
;
699 new_data2_offset
= OLD_SECTION_H(old_sbss_index
).sh_offset
;
700 new_data2_index
= old_sbss_index
;
703 for (old_mdebug_index
= 1; old_mdebug_index
< (int) old_file_h
->e_shnum
;
707 fprintf (stderr
, "Looking for .mdebug - found %s\n",
708 old_section_names
+ OLD_SECTION_H (old_mdebug_index
).sh_name
);
710 if (!strcmp (old_section_names
+ OLD_SECTION_H (old_mdebug_index
).sh_name
,
714 if (old_mdebug_index
== old_file_h
->e_shnum
)
715 old_mdebug_index
= 0;
716 #else /* not (__sony_news && _SYSTYPE_SYSV) */
717 old_bss_addr
= OLD_SECTION_H (old_bss_index
).sh_addr
;
718 old_bss_size
= OLD_SECTION_H (old_bss_index
).sh_size
;
719 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
720 #if defined (emacs) || !defined (DEBUG)
721 new_bss_addr
= (ElfW(Addr
)) sbrk (0);
723 new_bss_addr
= old_bss_addr
+ old_bss_size
+ 0x1234;
725 new_data2_addr
= old_bss_addr
;
726 new_data2_size
= new_bss_addr
- old_bss_addr
;
727 #if !defined (__sony_news) || !defined (_SYSTYPE_SYSV)
728 new_data2_offset
= OLD_SECTION_H (old_bss_index
).sh_offset
;
729 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
732 fprintf (stderr
, "old_bss_index %d\n", old_bss_index
);
733 fprintf (stderr
, "old_bss_addr %x\n", old_bss_addr
);
734 fprintf (stderr
, "old_bss_size %x\n", old_bss_size
);
735 fprintf (stderr
, "new_bss_addr %x\n", new_bss_addr
);
736 fprintf (stderr
, "new_data2_addr %x\n", new_data2_addr
);
737 fprintf (stderr
, "new_data2_size %x\n", new_data2_size
);
738 fprintf (stderr
, "new_data2_offset %x\n", new_data2_offset
);
741 if ((unsigned) new_bss_addr
< (unsigned) old_bss_addr
+ old_bss_size
)
742 fatal (".bss shrank when undumping???\n", 0, 0);
744 /* Set the output file to the right size and mmap it. Set
745 * pointers to various interesting objects. stat_buf still has
749 new_file
= open (new_name
, O_RDWR
| O_CREAT
, 0666);
751 fatal ("Can't creat (%s): errno %d\n", new_name
, errno
);
753 new_file_size
= stat_buf
.st_size
+ old_file_h
->e_shentsize
+ new_data2_size
;
755 if (ftruncate (new_file
, new_file_size
))
756 fatal ("Can't ftruncate (%s): errno %d\n", new_name
, errno
);
758 #ifdef UNEXEC_USE_MAP_PRIVATE
759 new_base
= mmap ((caddr_t
) 0, new_file_size
, PROT_READ
| PROT_WRITE
,
760 MAP_PRIVATE
, new_file
, 0);
762 new_base
= mmap ((caddr_t
) 0, new_file_size
, PROT_READ
| PROT_WRITE
,
763 MAP_SHARED
, new_file
, 0);
766 if (new_base
== (caddr_t
) -1)
767 fatal ("Can't mmap (%s): errno %d\n", new_name
, errno
);
769 new_file_h
= (ElfW(Ehdr
) *) new_base
;
770 new_program_h
= (ElfW(Phdr
) *) ((byte
*) new_base
+ old_file_h
->e_phoff
);
771 new_section_h
= (ElfW(Shdr
) *)
772 ((byte
*) new_base
+ old_file_h
->e_shoff
+ new_data2_size
);
774 /* Make our new file, program and section headers as copies of the
778 memcpy (new_file_h
, old_file_h
, old_file_h
->e_ehsize
);
779 memcpy (new_program_h
, old_program_h
,
780 old_file_h
->e_phnum
* old_file_h
->e_phentsize
);
782 /* Modify the e_shstrndx if necessary. */
783 PATCH_INDEX (new_file_h
->e_shstrndx
);
785 /* Fix up file header. We'll add one section. Section header is
789 new_file_h
->e_shoff
+= new_data2_size
;
790 new_file_h
->e_shnum
+= 1;
793 fprintf (stderr
, "Old section offset %x\n", old_file_h
->e_shoff
);
794 fprintf (stderr
, "Old section count %d\n", old_file_h
->e_shnum
);
795 fprintf (stderr
, "New section offset %x\n", new_file_h
->e_shoff
);
796 fprintf (stderr
, "New section count %d\n", new_file_h
->e_shnum
);
799 /* Fix up a new program header. Extend the writable data segment so
800 * that the bss area is covered too. Find that segment by looking
801 * for a segment that ends just before the .bss area. Make sure
802 * that no segments are above the new .data2. Put a loop at the end
803 * to adjust the offset and address of any segment that is above
804 * data2, just in case we decide to allow this later.
807 for (n
= new_file_h
->e_phnum
- 1; n
>= 0; n
--)
809 /* Compute maximum of all requirements for alignment of section. */
810 int alignment
= (NEW_PROGRAM_H (n
)).p_align
;
811 if ((OLD_SECTION_H (old_bss_index
)).sh_addralign
> alignment
)
812 alignment
= OLD_SECTION_H (old_bss_index
).sh_addralign
;
814 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
815 if (NEW_PROGRAM_H (n
).p_vaddr
+ NEW_PROGRAM_H (n
).p_filesz
816 > round_up (old_bss_addr
, alignment
))
817 fatal ("Program segment above .bss in %s\n", old_name
, 0);
818 #else /* not (__sony_news && _SYSTYPE_SYSV) */
819 if (NEW_PROGRAM_H (n
).p_vaddr
+ NEW_PROGRAM_H (n
).p_filesz
> old_bss_addr
)
820 fatal ("Program segment above .bss in %s\n", old_name
, 0);
821 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
823 if (NEW_PROGRAM_H (n
).p_type
== PT_LOAD
824 && (round_up ((NEW_PROGRAM_H (n
)).p_vaddr
825 + (NEW_PROGRAM_H (n
)).p_filesz
,
827 == round_up (old_bss_addr
, alignment
)))
831 fatal ("Couldn't find segment next to .bss in %s\n", old_name
, 0);
833 /* Make sure that the size includes any padding before the old .bss
835 NEW_PROGRAM_H (n
).p_filesz
= new_bss_addr
- NEW_PROGRAM_H (n
).p_vaddr
;
836 NEW_PROGRAM_H (n
).p_memsz
= NEW_PROGRAM_H (n
).p_filesz
;
838 #if 0 /* Maybe allow section after data2 - does this ever happen? */
839 for (n
= new_file_h
->e_phnum
- 1; n
>= 0; n
--)
841 if (NEW_PROGRAM_H (n
).p_vaddr
842 && NEW_PROGRAM_H (n
).p_vaddr
>= new_data2_addr
)
843 NEW_PROGRAM_H (n
).p_vaddr
+= new_data2_size
- old_bss_size
;
845 if (NEW_PROGRAM_H (n
).p_offset
>= new_data2_offset
)
846 NEW_PROGRAM_H (n
).p_offset
+= new_data2_size
;
850 /* Fix up section headers based on new .data2 section. Any section
851 * whose offset or virtual address is after the new .data2 section
852 * gets its value adjusted. .bss size becomes zero and new address
853 * is set. data2 section header gets added by copying the existing
854 * .data header and modifying the offset, address and size.
856 for (old_data_index
= 1; old_data_index
< (int) old_file_h
->e_shnum
;
858 if (!strcmp (old_section_names
+ OLD_SECTION_H (old_data_index
).sh_name
,
861 if (old_data_index
== old_file_h
->e_shnum
)
862 fatal ("Can't find .data in %s.\n", old_name
, 0);
864 /* Walk through all section headers, insert the new data2 section right
865 before the new bss section. */
866 for (n
= 1, nn
= 1; n
< (int) old_file_h
->e_shnum
; n
++, nn
++)
870 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
871 /* If it is (s)bss section, insert the new data2 section before it. */
872 /* new_data2_index is the index of either old_sbss or old_bss, that was
873 chosen as a section for new_data2. */
874 temp_index
= new_data2_index
;
875 #else /* not (__sony_news && _SYSTYPE_SYSV) */
876 /* If it is bss section, insert the new data2 section before it. */
877 temp_index
= old_bss_index
;
878 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
881 /* Steal the data section header for this data2 section. */
882 memcpy (&NEW_SECTION_H (nn
), &OLD_SECTION_H (old_data_index
),
883 new_file_h
->e_shentsize
);
885 NEW_SECTION_H (nn
).sh_addr
= new_data2_addr
;
886 NEW_SECTION_H (nn
).sh_offset
= new_data2_offset
;
887 NEW_SECTION_H (nn
).sh_size
= new_data2_size
;
888 /* Use the bss section's alignment. This will assure that the
889 new data2 section always be placed in the same spot as the old
890 bss section by any other application. */
891 NEW_SECTION_H (nn
).sh_addralign
= OLD_SECTION_H (n
).sh_addralign
;
893 /* Now copy over what we have in the memory now. */
894 memcpy (NEW_SECTION_H (nn
).sh_offset
+ new_base
,
895 (caddr_t
) OLD_SECTION_H (n
).sh_addr
,
900 memcpy (&NEW_SECTION_H (nn
), &OLD_SECTION_H (n
),
901 old_file_h
->e_shentsize
);
903 if (n
== old_bss_index
904 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
905 /* The new bss and sbss section's size is zero, and its file offset
906 and virtual address should be off by NEW_DATA2_SIZE. */
907 || n
== old_sbss_index
908 #endif /* __sony_news and _SYSTYPE_SYSV */
911 /* NN should be `old_bss_index + 1' at this point. */
912 NEW_SECTION_H (nn
).sh_offset
+= new_data2_size
;
913 NEW_SECTION_H (nn
).sh_addr
+= new_data2_size
;
914 /* Let the new bss section address alignment be the same as the
915 section address alignment followed the old bss section, so
916 this section will be placed in exactly the same place. */
917 NEW_SECTION_H (nn
).sh_addralign
= OLD_SECTION_H (nn
).sh_addralign
;
918 NEW_SECTION_H (nn
).sh_size
= 0;
922 /* Any section that was original placed AFTER the bss
923 section should now be off by NEW_DATA2_SIZE. */
924 #ifdef SOLARIS_POWERPC
925 /* On PPC Reference Platform running Solaris 2.5.1
926 the plt section is also of type NOBI like the bss section.
927 (not really stored) and therefore sections after the bss
928 section start at the plt offset. The plt section is always
929 the one just before the bss section.
930 It would be better to put the new data section before
931 the .plt section, or use libelf instead.
932 Erik Deumens, deumens@qtp.ufl.edu. */
933 if (NEW_SECTION_H (nn
).sh_offset
934 >= OLD_SECTION_H (old_bss_index
-1).sh_offset
)
935 NEW_SECTION_H (nn
).sh_offset
+= new_data2_size
;
937 if (round_up (NEW_SECTION_H (nn
).sh_offset
,
938 OLD_SECTION_H (old_bss_index
).sh_addralign
)
940 NEW_SECTION_H (nn
).sh_offset
+= new_data2_size
;
942 /* Any section that was originally placed after the section
943 header table should now be off by the size of one section
944 header table entry. */
945 if (NEW_SECTION_H (nn
).sh_offset
> new_file_h
->e_shoff
)
946 NEW_SECTION_H (nn
).sh_offset
+= new_file_h
->e_shentsize
;
949 /* If any section hdr refers to the section after the new .data
950 section, make it refer to next one because we have inserted
951 a new section in between. */
953 PATCH_INDEX (NEW_SECTION_H (nn
).sh_link
);
954 /* For symbol tables, info is a symbol table index,
955 so don't change it. */
956 if (NEW_SECTION_H (nn
).sh_type
!= SHT_SYMTAB
957 && NEW_SECTION_H (nn
).sh_type
!= SHT_DYNSYM
)
958 PATCH_INDEX (NEW_SECTION_H (nn
).sh_info
);
960 /* Now, start to copy the content of sections. */
961 if (NEW_SECTION_H (nn
).sh_type
== SHT_NULL
962 || NEW_SECTION_H (nn
).sh_type
== SHT_NOBITS
)
965 /* Write out the sections. .data and .data1 (and data2, called
966 ".data" in the strings table) get copied from the current process
967 instead of the old file. */
968 if (!strcmp (old_section_names
+ NEW_SECTION_H (n
).sh_name
, ".data")
969 #ifdef _nec_ews_svr4 /* hir, 1994.6.13 */
970 || !strcmp ((old_section_names
+ NEW_SECTION_H(n
).sh_name
),
973 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
974 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
976 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
978 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
980 #endif /* __sony_news && _SYSTYPE_SYSV */
981 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
983 src
= (caddr_t
) OLD_SECTION_H (n
).sh_addr
;
985 src
= old_base
+ OLD_SECTION_H (n
).sh_offset
;
987 memcpy (NEW_SECTION_H (nn
).sh_offset
+ new_base
, src
,
988 NEW_SECTION_H (nn
).sh_size
);
991 /* Update Alpha COFF symbol table: */
992 if (strcmp (old_section_names
+ OLD_SECTION_H (n
).sh_name
, ".mdebug")
995 pHDRR symhdr
= (pHDRR
) (NEW_SECTION_H (nn
).sh_offset
+ new_base
);
997 symhdr
->cbLineOffset
+= new_data2_size
;
998 symhdr
->cbDnOffset
+= new_data2_size
;
999 symhdr
->cbPdOffset
+= new_data2_size
;
1000 symhdr
->cbSymOffset
+= new_data2_size
;
1001 symhdr
->cbOptOffset
+= new_data2_size
;
1002 symhdr
->cbAuxOffset
+= new_data2_size
;
1003 symhdr
->cbSsOffset
+= new_data2_size
;
1004 symhdr
->cbSsExtOffset
+= new_data2_size
;
1005 symhdr
->cbFdOffset
+= new_data2_size
;
1006 symhdr
->cbRfdOffset
+= new_data2_size
;
1007 symhdr
->cbExtOffset
+= new_data2_size
;
1009 #endif /* __alpha__ */
1011 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
1012 if (NEW_SECTION_H (nn
).sh_type
== SHT_MIPS_DEBUG
&& old_mdebug_index
)
1014 int diff
= NEW_SECTION_H(nn
).sh_offset
1015 - OLD_SECTION_H(old_mdebug_index
).sh_offset
;
1016 HDRR
*phdr
= (HDRR
*)(NEW_SECTION_H (nn
).sh_offset
+ new_base
);
1020 phdr
->cbLineOffset
+= diff
;
1021 phdr
->cbDnOffset
+= diff
;
1022 phdr
->cbPdOffset
+= diff
;
1023 phdr
->cbSymOffset
+= diff
;
1024 phdr
->cbOptOffset
+= diff
;
1025 phdr
->cbAuxOffset
+= diff
;
1026 phdr
->cbSsOffset
+= diff
;
1027 phdr
->cbSsExtOffset
+= diff
;
1028 phdr
->cbFdOffset
+= diff
;
1029 phdr
->cbRfdOffset
+= diff
;
1030 phdr
->cbExtOffset
+= diff
;
1033 #endif /* __sony_news && _SYSTYPE_SYSV */
1034 /* If it is the symbol table, its st_shndx field needs to be patched. */
1035 if (NEW_SECTION_H (nn
).sh_type
== SHT_SYMTAB
1036 || NEW_SECTION_H (nn
).sh_type
== SHT_DYNSYM
)
1038 ElfW(Shdr
) *spt
= &NEW_SECTION_H (nn
);
1039 unsigned int num
= spt
->sh_size
/ spt
->sh_entsize
;
1040 ElfW(Sym
) * sym
= (ElfW(Sym
) *) (NEW_SECTION_H (nn
).sh_offset
+
1042 for (; num
--; sym
++)
1044 if ((sym
->st_shndx
== SHN_UNDEF
)
1045 || (sym
->st_shndx
== SHN_ABS
)
1046 || (sym
->st_shndx
== SHN_COMMON
))
1049 PATCH_INDEX (sym
->st_shndx
);
1054 /* Update the symbol values of _edata and _end. */
1055 for (n
= new_file_h
->e_shnum
- 1; n
; n
--)
1058 ElfW(Sym
) *symp
, *symendp
;
1060 if (NEW_SECTION_H (n
).sh_type
!= SHT_DYNSYM
1061 && NEW_SECTION_H (n
).sh_type
!= SHT_SYMTAB
)
1064 symnames
= ((byte
*) new_base
1065 + NEW_SECTION_H (NEW_SECTION_H (n
).sh_link
).sh_offset
);
1066 symp
= (ElfW(Sym
) *) (NEW_SECTION_H (n
).sh_offset
+ new_base
);
1067 symendp
= (ElfW(Sym
) *) ((byte
*)symp
+ NEW_SECTION_H (n
).sh_size
);
1069 for (; symp
< symendp
; symp
++)
1070 if (strcmp ((char *) (symnames
+ symp
->st_name
), "_end") == 0
1071 || strcmp ((char *) (symnames
+ symp
->st_name
), "end") == 0
1072 || strcmp ((char *) (symnames
+ symp
->st_name
), "_edata") == 0
1073 || strcmp ((char *) (symnames
+ symp
->st_name
), "edata") == 0)
1074 memcpy (&symp
->st_value
, &new_bss_addr
, sizeof (new_bss_addr
));
1077 /* This loop seeks out relocation sections for the data section, so
1078 that it can undo relocations performed by the runtime linker. */
1079 for (n
= new_file_h
->e_shnum
- 1; n
; n
--)
1081 ElfW(Shdr
) section
= NEW_SECTION_H (n
);
1082 switch (section
.sh_type
) {
1087 /* This code handles two different size structs, but there should
1088 be no harm in that provided that r_offset is always the first
1090 nn
= section
.sh_info
;
1091 if (!strcmp (old_section_names
+ NEW_SECTION_H (nn
).sh_name
, ".data")
1092 || !strcmp ((old_section_names
+ NEW_SECTION_H (nn
).sh_name
),
1095 ElfW(Addr
) offset
= NEW_SECTION_H (nn
).sh_addr
-
1096 NEW_SECTION_H (nn
).sh_offset
;
1097 caddr_t reloc
= old_base
+ section
.sh_offset
, end
;
1098 for (end
= reloc
+ section
.sh_size
; reloc
< end
;
1099 reloc
+= section
.sh_entsize
)
1101 ElfW(Addr
) addr
= ((ElfW(Rel
) *) reloc
)->r_offset
- offset
;
1103 /* The Alpha ELF binutils currently have a bug that
1104 sometimes results in relocs that contain all
1105 zeroes. Work around this for now... */
1106 if (((ElfW(Rel
) *) reloc
)->r_offset
== 0)
1109 memcpy (new_base
+ addr
, old_base
+ addr
, sizeof(ElfW(Addr
)));
1116 #ifdef UNEXEC_USE_MAP_PRIVATE
1117 if (lseek (new_file
, 0, SEEK_SET
) == -1)
1118 fatal ("Can't rewind (%s): errno %d\n", new_name
, errno
);
1120 if (write (new_file
, new_base
, new_file_size
) != new_file_size
)
1121 fatal ("Can't write (%s): errno %d\n", new_name
, errno
);
1124 /* Close the files and make the new file executable. */
1126 if (close (old_file
))
1127 fatal ("Can't close (%s): errno %d\n", old_name
, errno
);
1129 if (close (new_file
))
1130 fatal ("Can't close (%s): errno %d\n", new_name
, errno
);
1132 if (stat (new_name
, &stat_buf
) == -1)
1133 fatal ("Can't stat (%s): errno %d\n", new_name
, errno
);
1137 stat_buf
.st_mode
|= 0111 & ~n
;
1138 if (chmod (new_name
, stat_buf
.st_mode
) == -1)
1139 fatal ("Can't chmod (%s): errno %d\n", new_name
, errno
);