1 /* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992, 1999, 2000
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 * Bss_start indicates how much of the data segment is to be saved in the
56 * a.out file and restored when the program is executed. It gives the lowest
57 * unsaved address, and is rounded up to a page boundary. The default when 0
58 * is given assumes that the entire data segment is to be stored, including
59 * the previous data and bss as well as any additional storage allocated with
62 * The new file is set up to start at entry_address.
66 /* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
69 * Basic theory: the data space of the running process needs to be
70 * dumped to the output file. Normally we would just enlarge the size
71 * of .data, scooting everything down. But we can't do that in ELF,
72 * because there is often something between the .data space and the
75 * In the temacs dump below, notice that the Global Offset Table
76 * (.got) and the Dynamic link data (.dynamic) come between .data1 and
77 * .bss. It does not work to overlap .data with these fields.
79 * The solution is to create a new .data segment. This segment is
80 * filled with data from the current process. Since the contents of
81 * various sections refer to sections by index, the new .data segment
82 * is made the last in the table to avoid changing any existing index.
84 * This is an example of how the section headers are changed. "Addr"
85 * is a process virtual address. "Offset" is a file offset.
87 raid:/nfs/raid/src/dist-18.56/src> dump -h temacs
91 **** SECTION HEADER TABLE ****
92 [No] Type Flags Addr Offset Size Name
93 Link Info Adralgn Entsize
95 [1] 1 2 0x80480d4 0xd4 0x13 .interp
98 [2] 5 2 0x80480e8 0xe8 0x388 .hash
101 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
104 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
107 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
110 [6] 1 6 0x8049348 0x1348 0x3 .init
113 [7] 1 6 0x804934c 0x134c 0x680 .plt
116 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
119 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
122 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
125 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
128 [12] 1 3 0x8088330 0x3f330 0x20afc .data
131 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
134 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
137 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
140 [16] 8 3 0x80a98f4 0x608f4 0x449c .bss
143 [17] 2 0 0 0x608f4 0x9b90 .symtab
146 [18] 3 0 0 0x6a484 0x8526 .strtab
149 [19] 3 0 0 0x729aa 0x93 .shstrtab
152 [20] 1 0 0 0x72a3d 0x68b7 .comment
155 raid:/nfs/raid/src/dist-18.56/src> dump -h xemacs
159 **** SECTION HEADER TABLE ****
160 [No] Type Flags Addr Offset Size Name
161 Link Info Adralgn Entsize
163 [1] 1 2 0x80480d4 0xd4 0x13 .interp
166 [2] 5 2 0x80480e8 0xe8 0x388 .hash
169 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
172 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
175 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
178 [6] 1 6 0x8049348 0x1348 0x3 .init
181 [7] 1 6 0x804934c 0x134c 0x680 .plt
184 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
187 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
190 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
193 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
196 [12] 1 3 0x8088330 0x3f330 0x20afc .data
199 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
202 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
205 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
208 [16] 8 3 0x80c6800 0x7d800 0 .bss
211 [17] 2 0 0 0x7d800 0x9b90 .symtab
214 [18] 3 0 0 0x87390 0x8526 .strtab
217 [19] 3 0 0 0x8f8b6 0x93 .shstrtab
220 [20] 1 0 0 0x8f949 0x68b7 .comment
223 [21] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
226 * This is an example of how the file header is changed. "Shoff" is
227 * the section header offset within the file. Since that table is
228 * after the new .data section, it is moved. "Shnum" is the number of
229 * sections, which we increment.
231 * "Phoff" is the file offset to the program header. "Phentsize" and
232 * "Shentsz" are the program and section header entries sizes respectively.
233 * These can be larger than the apparent struct sizes.
235 raid:/nfs/raid/src/dist-18.56/src> dump -f temacs
240 Class Data Type Machine Version
241 Entry Phoff Shoff Flags Ehsize
242 Phentsize Phnum Shentsz Shnum Shstrndx
245 0x80499cc 0x34 0x792f4 0 0x34
248 raid:/nfs/raid/src/dist-18.56/src> dump -f xemacs
253 Class Data Type Machine Version
254 Entry Phoff Shoff Flags Ehsize
255 Phentsize Phnum Shentsz Shnum Shstrndx
258 0x80499cc 0x34 0x96200 0 0x34
261 * These are the program headers. "Offset" is the file offset to the
262 * segment. "Vaddr" is the memory load address. "Filesz" is the
263 * segment size as it appears in the file, and "Memsz" is the size in
264 * memory. Below, the third segment is the code and the fourth is the
265 * data: the difference between Filesz and Memsz is .bss
267 raid:/nfs/raid/src/dist-18.56/src> dump -o temacs
270 ***** PROGRAM EXECUTION HEADER *****
271 Type Offset Vaddr Paddr
272 Filesz Memsz Flags Align
281 0x3f2f9 0x3f2f9 5 0x1000
283 1 0x3f330 0x8088330 0
284 0x215c4 0x25a60 7 0x1000
286 2 0x60874 0x80a9874 0
289 raid:/nfs/raid/src/dist-18.56/src> dump -o xemacs
292 ***** PROGRAM EXECUTION HEADER *****
293 Type Offset Vaddr Paddr
294 Filesz Memsz Flags Align
303 0x3f2f9 0x3f2f9 5 0x1000
305 1 0x3f330 0x8088330 0
306 0x3e4d0 0x3e4d0 7 0x1000
308 2 0x60874 0x80a9874 0
314 /* Modified by wtien@urbana.mcd.mot.com of Motorola Inc.
316 * The above mechanism does not work if the unexeced ELF file is being
317 * re-layout by other applications (such as `strip'). All the applications
318 * that re-layout the internal of ELF will layout all sections in ascending
319 * order of their file offsets. After the re-layout, the data2 section will
320 * still be the LAST section in the section header vector, but its file offset
321 * is now being pushed far away down, and causes part of it not to be mapped
322 * in (ie. not covered by the load segment entry in PHDR vector), therefore
323 * causes the new binary to fail.
325 * The solution is to modify the unexec algorithm to insert the new data2
326 * section header right before the new bss section header, so their file
327 * offsets will be in the ascending order. Since some of the section's (all
328 * sections AFTER the bss section) indexes are now changed, we also need to
329 * modify some fields to make them point to the right sections. This is done
330 * by macro PATCH_INDEX. All the fields that need to be patched are:
332 * 1. ELF header e_shstrndx field.
333 * 2. section header sh_link and sh_info field.
334 * 3. symbol table entry st_shndx field.
336 * The above example now should look like:
338 **** SECTION HEADER TABLE ****
339 [No] Type Flags Addr Offset Size Name
340 Link Info Adralgn Entsize
342 [1] 1 2 0x80480d4 0xd4 0x13 .interp
345 [2] 5 2 0x80480e8 0xe8 0x388 .hash
348 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
351 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
354 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
357 [6] 1 6 0x8049348 0x1348 0x3 .init
360 [7] 1 6 0x804934c 0x134c 0x680 .plt
363 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
366 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
369 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
372 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
375 [12] 1 3 0x8088330 0x3f330 0x20afc .data
378 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
381 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
384 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
387 [16] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
390 [17] 8 3 0x80c6800 0x7d800 0 .bss
393 [18] 2 0 0 0x7d800 0x9b90 .symtab
396 [19] 3 0 0 0x87390 0x8526 .strtab
399 [20] 3 0 0 0x8f8b6 0x93 .shstrtab
402 [21] 1 0 0 0x8f949 0x68b7 .comment
407 /* We do not use mmap because that fails with NFS.
408 Instead we read the whole file, modify it, and write it out. */
411 #define fatal(a, b, c) fprintf (stderr, a, b, c), exit (1)
415 extern void fatal (char *, ...);
418 #include <sys/types.h>
420 #include <sys/stat.h>
425 #if !defined (__NetBSD__) && !defined (__OpenBSD__)
428 #include <sys/mman.h>
429 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
430 #include <sys/elf_mips.h>
432 #endif /* __sony_news && _SYSTYPE_SYSV */
434 #include <syms.h> /* for HDRR declaration */
437 #if defined (__alpha__) && !defined (__NetBSD__) && !defined (__OpenBSD__)
438 /* Declare COFF debugging symbol table. This used to be in
439 /usr/include/sym.h, but this file is no longer included in Red Hat
440 5.0 and presumably in any other glibc 2.x based distribution. */
468 #define cbHDRR sizeof(HDRR)
469 #define hdrNil ((pHDRR)0)
474 * NetBSD does not have normal-looking user-land ELF support.
476 # if defined __alpha__ || defined __sparc_v9__
481 # include <sys/exec_elf.h>
484 # define PT_LOAD Elf_pt_load
485 # if 0 /* was in pkgsrc patches for 20.7 */
486 # define SHT_PROGBITS Elf_sht_progbits
488 # define SHT_SYMTAB Elf_sht_symtab
489 # define SHT_DYNSYM Elf_sht_dynsym
490 # define SHT_NULL Elf_sht_null
491 # define SHT_NOBITS Elf_sht_nobits
492 # define SHT_REL Elf_sht_rel
493 # define SHT_RELA Elf_sht_rela
495 # define SHN_UNDEF Elf_eshn_undefined
496 # define SHN_ABS Elf_eshn_absolute
497 # define SHN_COMMON Elf_eshn_common
498 # endif /* !PT_LOAD */
501 # include <sys/exec_ecoff.h>
502 # define HDRR struct ecoff_symhdr
503 # define pHDRR HDRR *
504 # endif /* __alpha__ */
506 #ifdef __mips__ /* was in pkgsrc patches for 20.7 */
507 # define SHT_MIPS_DEBUG DT_MIPS_FLAGS
508 # define HDRR struct Elf_Shdr
509 #endif /* __mips__ */
510 #endif /* __NetBSD__ */
513 # include <sys/exec_elf.h>
516 #if __GNU_LIBRARY__ - 0 >= 6
517 # include <link.h> /* get ElfW etc */
522 # define ElfBitsW(bits, type) Elf##bits##_##type
524 # define ElfBitsW(bits, type) Elf/**/bits/**/_/**/type
531 /* This macro expands `bits' before invoking ElfBitsW. */
532 # define ElfExpandBitsW(bits, type) ElfBitsW (bits, type)
533 # define ElfW(type) ElfExpandBitsW (ELFSIZE, type)
536 #ifndef ELF_BSS_SECTION_NAME
537 #define ELF_BSS_SECTION_NAME ".bss"
540 /* Get the address of a particular section or program header entry,
541 * accounting for the size of the entries.
544 On PPC Reference Platform running Solaris 2.5.1
545 the plt section is also of type NOBI like the bss section.
546 (not really stored) and therefore sections after the bss
547 section start at the plt offset. The plt section is always
548 the one just before the bss section.
549 Thus, we modify the test from
550 if (NEW_SECTION_H (nn).sh_offset >= new_data2_offset)
552 if (NEW_SECTION_H (nn).sh_offset >=
553 OLD_SECTION_H (old_bss_index-1).sh_offset)
554 This is just a hack. We should put the new data section
555 before the .plt section.
556 And we should not have this routine at all but use
557 the libelf library to read the old file and create the new
559 The changed code is minimal and depends on prep set in m/prep.h
561 Quantum Theory Project
562 University of Florida
567 #define OLD_SECTION_H(n) \
568 (*(ElfW(Shdr) *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
569 #define NEW_SECTION_H(n) \
570 (*(ElfW(Shdr) *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
571 #define OLD_PROGRAM_H(n) \
572 (*(ElfW(Phdr) *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
573 #define NEW_PROGRAM_H(n) \
574 (*(ElfW(Phdr) *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
576 #define PATCH_INDEX(n) \
578 if ((int) (n) >= old_bss_index) \
580 typedef unsigned char byte
;
582 /* Round X up to a multiple of Y. */
594 /* Return the index of the section named NAME.
595 SECTION_NAMES, FILE_NAME and FILE_H give information
596 about the file we are looking in.
598 If we don't find the section NAME, that is a fatal error
599 if NOERROR is 0; we return -1 if NOERROR is nonzero. */
602 find_section (name
, section_names
, file_name
, old_file_h
, old_section_h
, noerror
)
606 ElfW(Ehdr
) *old_file_h
;
607 ElfW(Shdr
) *old_section_h
;
612 for (idx
= 1; idx
< old_file_h
->e_shnum
; idx
++)
615 fprintf (stderr
, "Looking for %s - found %s\n", name
,
616 section_names
+ OLD_SECTION_H (idx
).sh_name
);
618 if (!strcmp (section_names
+ OLD_SECTION_H (idx
).sh_name
,
622 if (idx
== old_file_h
->e_shnum
)
627 fatal ("Can't find %s in %s.\n", name
, file_name
);
633 /* ****************************************************************
638 * In ELF, this works by replacing the old .bss section with a new
639 * .data section, and inserting an empty .bss immediately afterwards.
643 unexec (new_name
, old_name
, data_start
, bss_start
, entry_address
)
644 char *new_name
, *old_name
;
645 unsigned data_start
, bss_start
, entry_address
;
647 int new_file
, old_file
, new_file_size
;
649 /* Pointers to the base of the image of the two files. */
650 caddr_t old_base
, new_base
;
652 /* Pointers to the file, program and section headers for the old and
654 ElfW(Ehdr
) *old_file_h
, *new_file_h
;
655 ElfW(Phdr
) *old_program_h
, *new_program_h
;
656 ElfW(Shdr
) *old_section_h
, *new_section_h
;
658 /* Point to the section name table in the old file. */
659 char *old_section_names
;
661 ElfW(Addr
) old_bss_addr
, new_bss_addr
;
662 ElfW(Word
) old_bss_size
, new_data2_size
;
663 ElfW(Off
) new_data2_offset
;
664 ElfW(Addr
) new_data2_addr
;
667 int old_bss_index
, old_sbss_index
;
668 int old_data_index
, new_data2_index
;
669 int old_mdebug_index
;
670 struct stat stat_buf
;
672 /* Open the old file, allocate a buffer of the right size, and read
673 in the file contents. */
675 old_file
= open (old_name
, O_RDONLY
);
678 fatal ("Can't open %s for reading: errno %d\n", old_name
, errno
);
680 if (fstat (old_file
, &stat_buf
) == -1)
681 fatal ("Can't fstat (%s): errno %d\n", old_name
, errno
);
683 old_base
= malloc (stat_buf
.st_size
);
686 fatal ("Can't allocate buffer for %s\n", old_name
);
689 fprintf (stderr
, "%s: malloc(%d) -> %x\n", old_name
, stat_buf
.st_size
,
693 if (read (old_file
, old_base
, stat_buf
.st_size
) != stat_buf
.st_size
)
694 fatal ("Didn't read all of %s: errno %d\n", old_name
, errno
);
696 /* Get pointers to headers & section names */
698 old_file_h
= (ElfW(Ehdr
) *) old_base
;
699 old_program_h
= (ElfW(Phdr
) *) ((byte
*) old_base
+ old_file_h
->e_phoff
);
700 old_section_h
= (ElfW(Shdr
) *) ((byte
*) old_base
+ old_file_h
->e_shoff
);
701 old_section_names
= (char *) old_base
702 + OLD_SECTION_H (old_file_h
->e_shstrndx
).sh_offset
;
704 /* Find the mdebug section, if any. */
706 old_mdebug_index
= find_section (".mdebug", old_section_names
,
707 old_name
, old_file_h
, old_section_h
, 1);
709 /* Find the old .bss section. Figure out parameters of the new
710 data2 and bss sections. */
712 old_bss_index
= find_section (".bss", old_section_names
,
713 old_name
, old_file_h
, old_section_h
, 0);
715 old_sbss_index
= find_section (".sbss", old_section_names
,
716 old_name
, old_file_h
, old_section_h
, 1);
717 if (old_sbss_index
!= -1)
718 if (OLD_SECTION_H (old_sbss_index
).sh_type
== SHT_PROGBITS
)
721 if (old_sbss_index
== -1)
723 old_bss_addr
= OLD_SECTION_H (old_bss_index
).sh_addr
;
724 old_bss_size
= OLD_SECTION_H (old_bss_index
).sh_size
;
725 new_data2_index
= old_bss_index
;
729 old_bss_addr
= OLD_SECTION_H (old_sbss_index
).sh_addr
;
730 old_bss_size
= OLD_SECTION_H (old_bss_index
).sh_size
731 + OLD_SECTION_H (old_sbss_index
).sh_size
;
732 new_data2_index
= old_sbss_index
;
735 /* Find the old .data section. Figure out parameters of
736 the new data2 and bss sections. */
738 old_data_index
= find_section (".data", old_section_names
,
739 old_name
, old_file_h
, old_section_h
, 0);
741 #if defined (emacs) || !defined (DEBUG)
742 new_bss_addr
= (ElfW(Addr
)) sbrk (0);
744 new_bss_addr
= old_bss_addr
+ old_bss_size
+ 0x1234;
746 new_data2_addr
= old_bss_addr
;
747 new_data2_size
= new_bss_addr
- old_bss_addr
;
748 new_data2_offset
= OLD_SECTION_H (old_data_index
).sh_offset
+
749 (new_data2_addr
- OLD_SECTION_H (old_data_index
).sh_addr
);
752 fprintf (stderr
, "old_bss_index %d\n", old_bss_index
);
753 fprintf (stderr
, "old_bss_addr %x\n", old_bss_addr
);
754 fprintf (stderr
, "old_bss_size %x\n", old_bss_size
);
755 fprintf (stderr
, "new_bss_addr %x\n", new_bss_addr
);
756 fprintf (stderr
, "new_data2_addr %x\n", new_data2_addr
);
757 fprintf (stderr
, "new_data2_size %x\n", new_data2_size
);
758 fprintf (stderr
, "new_data2_offset %x\n", new_data2_offset
);
761 if ((unsigned) new_bss_addr
< (unsigned) old_bss_addr
+ old_bss_size
)
762 fatal (".bss shrank when undumping???\n", 0, 0);
764 /* Set the output file to the right size. Allocate a buffer to hold
765 the image of the new file. Set pointers to various interesting
766 objects. stat_buf still has old_file data. */
768 new_file
= open (new_name
, O_RDWR
| O_CREAT
, 0666);
770 fatal ("Can't creat (%s): errno %d\n", new_name
, errno
);
772 new_file_size
= stat_buf
.st_size
+ old_file_h
->e_shentsize
+ new_data2_size
;
774 if (ftruncate (new_file
, new_file_size
))
775 fatal ("Can't ftruncate (%s): errno %d\n", new_name
, errno
);
777 new_base
= malloc (new_file_size
);
780 fatal ("Can't allocate buffer for %s\n", old_name
);
783 fprintf (stderr
, "%s: malloc(%d) -> %x\n", new_name
, new_file_size
787 new_file_h
= (ElfW(Ehdr
) *) new_base
;
788 new_program_h
= (ElfW(Phdr
) *) ((byte
*) new_base
+ old_file_h
->e_phoff
);
789 new_section_h
= (ElfW(Shdr
) *)
790 ((byte
*) new_base
+ old_file_h
->e_shoff
+ new_data2_size
);
792 /* Make our new file, program and section headers as copies of the
795 memcpy (new_file_h
, old_file_h
, old_file_h
->e_ehsize
);
796 memcpy (new_program_h
, old_program_h
,
797 old_file_h
->e_phnum
* old_file_h
->e_phentsize
);
799 /* Modify the e_shstrndx if necessary. */
800 PATCH_INDEX (new_file_h
->e_shstrndx
);
802 /* Fix up file header. We'll add one section. Section header is
805 new_file_h
->e_shoff
+= new_data2_size
;
806 new_file_h
->e_shnum
+= 1;
809 fprintf (stderr
, "Old section offset %x\n", old_file_h
->e_shoff
);
810 fprintf (stderr
, "Old section count %d\n", old_file_h
->e_shnum
);
811 fprintf (stderr
, "New section offset %x\n", new_file_h
->e_shoff
);
812 fprintf (stderr
, "New section count %d\n", new_file_h
->e_shnum
);
815 /* Fix up a new program header. Extend the writable data segment so
816 that the bss area is covered too. Find that segment by looking
817 for a segment that ends just before the .bss area. Make sure
818 that no segments are above the new .data2. Put a loop at the end
819 to adjust the offset and address of any segment that is above
820 data2, just in case we decide to allow this later. */
822 for (n
= new_file_h
->e_phnum
- 1; n
>= 0; n
--)
824 /* Compute maximum of all requirements for alignment of section. */
825 ElfW(Word
) alignment
= (NEW_PROGRAM_H (n
)).p_align
;
826 if ((OLD_SECTION_H (old_bss_index
)).sh_addralign
> alignment
)
827 alignment
= OLD_SECTION_H (old_bss_index
).sh_addralign
;
830 /* According to r02kar@x4u2.desy.de (Karsten Kuenne)
831 and oliva@gnu.org (Alexandre Oliva), on IRIX 5.2, we
832 always get "Program segment above .bss" when dumping
833 when the executable doesn't have an sbss section. */
834 if (old_sbss_index
!= -1)
836 if (NEW_PROGRAM_H (n
).p_vaddr
+ NEW_PROGRAM_H (n
).p_filesz
837 > (old_sbss_index
== -1
839 : round_up (old_bss_addr
, alignment
)))
840 fatal ("Program segment above .bss in %s\n", old_name
, 0);
842 if (NEW_PROGRAM_H (n
).p_type
== PT_LOAD
843 && (round_up ((NEW_PROGRAM_H (n
)).p_vaddr
844 + (NEW_PROGRAM_H (n
)).p_filesz
,
846 == round_up (old_bss_addr
, alignment
)))
850 fatal ("Couldn't find segment next to .bss in %s\n", old_name
, 0);
852 /* Make sure that the size includes any padding before the old .bss
854 NEW_PROGRAM_H (n
).p_filesz
= new_bss_addr
- NEW_PROGRAM_H (n
).p_vaddr
;
855 NEW_PROGRAM_H (n
).p_memsz
= NEW_PROGRAM_H (n
).p_filesz
;
857 #if 0 /* Maybe allow section after data2 - does this ever happen? */
858 for (n
= new_file_h
->e_phnum
- 1; n
>= 0; n
--)
860 if (NEW_PROGRAM_H (n
).p_vaddr
861 && NEW_PROGRAM_H (n
).p_vaddr
>= new_data2_addr
)
862 NEW_PROGRAM_H (n
).p_vaddr
+= new_data2_size
- old_bss_size
;
864 if (NEW_PROGRAM_H (n
).p_offset
>= new_data2_offset
)
865 NEW_PROGRAM_H (n
).p_offset
+= new_data2_size
;
869 /* Fix up section headers based on new .data2 section. Any section
870 whose offset or virtual address is after the new .data2 section
871 gets its value adjusted. .bss size becomes zero and new address
872 is set. data2 section header gets added by copying the existing
873 .data header and modifying the offset, address and size. */
874 for (old_data_index
= 1; old_data_index
< (int) old_file_h
->e_shnum
;
876 if (!strcmp (old_section_names
+ OLD_SECTION_H (old_data_index
).sh_name
,
879 if (old_data_index
== old_file_h
->e_shnum
)
880 fatal ("Can't find .data in %s.\n", old_name
, 0);
882 /* Walk through all section headers, insert the new data2 section right
883 before the new bss section. */
884 for (n
= 1, nn
= 1; n
< (int) old_file_h
->e_shnum
; n
++, nn
++)
887 /* If it is (s)bss section, insert the new data2 section before it. */
888 /* new_data2_index is the index of either old_sbss or old_bss, that was
889 chosen as a section for new_data2. */
890 if (n
== new_data2_index
)
892 /* Steal the data section header for this data2 section. */
893 memcpy (&NEW_SECTION_H (nn
), &OLD_SECTION_H (old_data_index
),
894 new_file_h
->e_shentsize
);
896 NEW_SECTION_H (nn
).sh_addr
= new_data2_addr
;
897 NEW_SECTION_H (nn
).sh_offset
= new_data2_offset
;
898 NEW_SECTION_H (nn
).sh_size
= new_data2_size
;
899 /* Use the bss section's alignment. This will assure that the
900 new data2 section always be placed in the same spot as the old
901 bss section by any other application. */
902 NEW_SECTION_H (nn
).sh_addralign
= OLD_SECTION_H (n
).sh_addralign
;
904 /* Now copy over what we have in the memory now. */
905 memcpy (NEW_SECTION_H (nn
).sh_offset
+ new_base
,
906 (caddr_t
) OLD_SECTION_H (n
).sh_addr
,
911 memcpy (&NEW_SECTION_H (nn
), &OLD_SECTION_H (n
),
912 old_file_h
->e_shentsize
);
914 if (n
== old_bss_index
915 /* The new bss and sbss section's size is zero, and its file offset
916 and virtual address should be off by NEW_DATA2_SIZE. */
917 || n
== old_sbss_index
920 /* NN should be `old_s?bss_index + 1' at this point. */
921 NEW_SECTION_H (nn
).sh_offset
=
922 NEW_SECTION_H (new_data2_index
).sh_offset
+ new_data2_size
;
923 NEW_SECTION_H (nn
).sh_addr
=
924 NEW_SECTION_H (new_data2_index
).sh_addr
+ new_data2_size
;
925 /* Let the new bss section address alignment be the same as the
926 section address alignment followed the old bss section, so
927 this section will be placed in exactly the same place. */
928 NEW_SECTION_H (nn
).sh_addralign
= OLD_SECTION_H (nn
).sh_addralign
;
929 NEW_SECTION_H (nn
).sh_size
= 0;
933 /* Any section that was original placed AFTER the bss
934 section should now be off by NEW_DATA2_SIZE. */
935 #ifdef SOLARIS_POWERPC
936 /* On PPC Reference Platform running Solaris 2.5.1
937 the plt section is also of type NOBI like the bss section.
938 (not really stored) and therefore sections after the bss
939 section start at the plt offset. The plt section is always
940 the one just before the bss section.
941 It would be better to put the new data section before
942 the .plt section, or use libelf instead.
943 Erik Deumens, deumens@qtp.ufl.edu. */
944 if (NEW_SECTION_H (nn
).sh_offset
945 >= OLD_SECTION_H (old_bss_index
-1).sh_offset
)
946 NEW_SECTION_H (nn
).sh_offset
+= new_data2_size
;
948 if (round_up (NEW_SECTION_H (nn
).sh_offset
,
949 OLD_SECTION_H (old_bss_index
).sh_addralign
)
951 NEW_SECTION_H (nn
).sh_offset
+= new_data2_size
;
953 /* Any section that was originally placed after the section
954 header table should now be off by the size of one section
955 header table entry. */
956 if (NEW_SECTION_H (nn
).sh_offset
> new_file_h
->e_shoff
)
957 NEW_SECTION_H (nn
).sh_offset
+= new_file_h
->e_shentsize
;
960 /* If any section hdr refers to the section after the new .data
961 section, make it refer to next one because we have inserted
962 a new section in between. */
964 PATCH_INDEX (NEW_SECTION_H (nn
).sh_link
);
965 /* For symbol tables, info is a symbol table index,
966 so don't change it. */
967 if (NEW_SECTION_H (nn
).sh_type
!= SHT_SYMTAB
968 && NEW_SECTION_H (nn
).sh_type
!= SHT_DYNSYM
)
969 PATCH_INDEX (NEW_SECTION_H (nn
).sh_info
);
971 if (old_sbss_index
!= -1)
972 if (!strcmp (old_section_names
+ NEW_SECTION_H (nn
).sh_name
, ".sbss"))
974 NEW_SECTION_H (nn
).sh_offset
=
975 round_up (NEW_SECTION_H (nn
).sh_offset
,
976 NEW_SECTION_H (nn
).sh_addralign
);
977 NEW_SECTION_H (nn
).sh_type
= SHT_PROGBITS
;
980 /* Now, start to copy the content of sections. */
981 if (NEW_SECTION_H (nn
).sh_type
== SHT_NULL
982 || NEW_SECTION_H (nn
).sh_type
== SHT_NOBITS
)
985 /* Write out the sections. .data and .data1 (and data2, called
986 ".data" in the strings table) get copied from the current process
987 instead of the old file. */
988 if (!strcmp (old_section_names
+ NEW_SECTION_H (n
).sh_name
, ".data")
989 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
991 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
993 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
995 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
997 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
999 || !strcmp (old_section_names
+ NEW_SECTION_H (nn
).sh_name
,
1001 src
= (caddr_t
) OLD_SECTION_H (n
).sh_addr
;
1003 src
= old_base
+ OLD_SECTION_H (n
).sh_offset
;
1005 memcpy (NEW_SECTION_H (nn
).sh_offset
+ new_base
, src
,
1006 NEW_SECTION_H (nn
).sh_size
);
1009 /* Update Alpha COFF symbol table: */
1010 if (strcmp (old_section_names
+ OLD_SECTION_H (n
).sh_name
, ".mdebug")
1013 pHDRR symhdr
= (pHDRR
) (NEW_SECTION_H (nn
).sh_offset
+ new_base
);
1015 symhdr
->cbLineOffset
+= new_data2_size
;
1016 symhdr
->cbDnOffset
+= new_data2_size
;
1017 symhdr
->cbPdOffset
+= new_data2_size
;
1018 symhdr
->cbSymOffset
+= new_data2_size
;
1019 symhdr
->cbOptOffset
+= new_data2_size
;
1020 symhdr
->cbAuxOffset
+= new_data2_size
;
1021 symhdr
->cbSsOffset
+= new_data2_size
;
1022 symhdr
->cbSsExtOffset
+= new_data2_size
;
1023 symhdr
->cbFdOffset
+= new_data2_size
;
1024 symhdr
->cbRfdOffset
+= new_data2_size
;
1025 symhdr
->cbExtOffset
+= new_data2_size
;
1027 #endif /* __alpha__ */
1029 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
1030 if (NEW_SECTION_H (nn
).sh_type
== SHT_MIPS_DEBUG
1031 && old_mdebug_index
!= -1)
1033 int diff
= NEW_SECTION_H(nn
).sh_offset
1034 - OLD_SECTION_H(old_mdebug_index
).sh_offset
;
1035 HDRR
*phdr
= (HDRR
*)(NEW_SECTION_H (nn
).sh_offset
+ new_base
);
1039 phdr
->cbLineOffset
+= diff
;
1040 phdr
->cbDnOffset
+= diff
;
1041 phdr
->cbPdOffset
+= diff
;
1042 phdr
->cbSymOffset
+= diff
;
1043 phdr
->cbOptOffset
+= diff
;
1044 phdr
->cbAuxOffset
+= diff
;
1045 phdr
->cbSsOffset
+= diff
;
1046 phdr
->cbSsExtOffset
+= diff
;
1047 phdr
->cbFdOffset
+= diff
;
1048 phdr
->cbRfdOffset
+= diff
;
1049 phdr
->cbExtOffset
+= diff
;
1052 #endif /* __sony_news && _SYSTYPE_SYSV */
1055 /* Adjust the HDRR offsets in .mdebug and copy the
1056 line data if it's in its usual 'hole' in the object.
1057 Makes the new file debuggable with dbx.
1058 patches up two problems: the absolute file offsets
1059 in the HDRR record of .mdebug (see /usr/include/syms.h), and
1060 the ld bug that gets the line table in a hole in the
1061 elf file rather than in the .mdebug section proper.
1062 David Anderson. davea@sgi.com Jan 16,1994. */
1063 if (n
== old_mdebug_index
)
1065 #define MDEBUGADJUST(__ct,__fileaddr) \
1066 if (n_phdrr->__ct > 0) \
1068 n_phdrr->__fileaddr += movement; \
1071 HDRR
* o_phdrr
= (HDRR
*)((byte
*)old_base
+ OLD_SECTION_H (n
).sh_offset
);
1072 HDRR
* n_phdrr
= (HDRR
*)((byte
*)new_base
+ NEW_SECTION_H (nn
).sh_offset
);
1073 unsigned movement
= new_data2_size
;
1075 MDEBUGADJUST (idnMax
, cbDnOffset
);
1076 MDEBUGADJUST (ipdMax
, cbPdOffset
);
1077 MDEBUGADJUST (isymMax
, cbSymOffset
);
1078 MDEBUGADJUST (ioptMax
, cbOptOffset
);
1079 MDEBUGADJUST (iauxMax
, cbAuxOffset
);
1080 MDEBUGADJUST (issMax
, cbSsOffset
);
1081 MDEBUGADJUST (issExtMax
, cbSsExtOffset
);
1082 MDEBUGADJUST (ifdMax
, cbFdOffset
);
1083 MDEBUGADJUST (crfd
, cbRfdOffset
);
1084 MDEBUGADJUST (iextMax
, cbExtOffset
);
1085 /* The Line Section, being possible off in a hole of the object,
1086 requires special handling. */
1087 if (n_phdrr
->cbLine
> 0)
1089 if (o_phdrr
->cbLineOffset
> (OLD_SECTION_H (n
).sh_offset
1090 + OLD_SECTION_H (n
).sh_size
))
1092 /* line data is in a hole in elf. do special copy and adjust
1093 for this ld mistake.
1095 n_phdrr
->cbLineOffset
+= movement
;
1097 memcpy (n_phdrr
->cbLineOffset
+ new_base
,
1098 o_phdrr
->cbLineOffset
+ old_base
, n_phdrr
->cbLine
);
1102 /* somehow line data is in .mdebug as it is supposed to be. */
1103 MDEBUGADJUST (cbLine
, cbLineOffset
);
1109 /* If it is the symbol table, its st_shndx field needs to be patched. */
1110 if (NEW_SECTION_H (nn
).sh_type
== SHT_SYMTAB
1111 || NEW_SECTION_H (nn
).sh_type
== SHT_DYNSYM
)
1113 ElfW(Shdr
) *spt
= &NEW_SECTION_H (nn
);
1114 unsigned int num
= spt
->sh_size
/ spt
->sh_entsize
;
1115 ElfW(Sym
) * sym
= (ElfW(Sym
) *) (NEW_SECTION_H (nn
).sh_offset
+
1117 for (; num
--; sym
++)
1119 if ((sym
->st_shndx
== SHN_UNDEF
)
1120 || (sym
->st_shndx
== SHN_ABS
)
1121 || (sym
->st_shndx
== SHN_COMMON
))
1124 PATCH_INDEX (sym
->st_shndx
);
1129 /* Update the symbol values of _edata and _end. */
1130 for (n
= new_file_h
->e_shnum
- 1; n
; n
--)
1133 ElfW(Sym
) *symp
, *symendp
;
1135 if (NEW_SECTION_H (n
).sh_type
!= SHT_DYNSYM
1136 && NEW_SECTION_H (n
).sh_type
!= SHT_SYMTAB
)
1139 symnames
= ((byte
*) new_base
1140 + NEW_SECTION_H (NEW_SECTION_H (n
).sh_link
).sh_offset
);
1141 symp
= (ElfW(Sym
) *) (NEW_SECTION_H (n
).sh_offset
+ new_base
);
1142 symendp
= (ElfW(Sym
) *) ((byte
*)symp
+ NEW_SECTION_H (n
).sh_size
);
1144 for (; symp
< symendp
; symp
++)
1145 if (strcmp ((char *) (symnames
+ symp
->st_name
), "_end") == 0
1146 || strcmp ((char *) (symnames
+ symp
->st_name
), "end") == 0
1147 || strcmp ((char *) (symnames
+ symp
->st_name
), "_edata") == 0
1148 || strcmp ((char *) (symnames
+ symp
->st_name
), "edata") == 0)
1149 memcpy (&symp
->st_value
, &new_bss_addr
, sizeof (new_bss_addr
));
1152 /* This loop seeks out relocation sections for the data section, so
1153 that it can undo relocations performed by the runtime linker. */
1154 for (n
= new_file_h
->e_shnum
- 1; n
; n
--)
1156 ElfW(Shdr
) section
= NEW_SECTION_H (n
);
1157 switch (section
.sh_type
) {
1162 /* This code handles two different size structs, but there should
1163 be no harm in that provided that r_offset is always the first
1165 nn
= section
.sh_info
;
1166 if (!strcmp (old_section_names
+ NEW_SECTION_H (nn
).sh_name
, ".data")
1167 || !strcmp ((old_section_names
+ NEW_SECTION_H (nn
).sh_name
),
1169 || !strcmp ((old_section_names
+ NEW_SECTION_H (nn
).sh_name
),
1171 || !strcmp ((old_section_names
+ NEW_SECTION_H (nn
).sh_name
),
1173 || !strcmp ((old_section_names
+ NEW_SECTION_H (nn
).sh_name
),
1175 || !strcmp ((old_section_names
+ NEW_SECTION_H (nn
).sh_name
),
1178 ElfW(Addr
) offset
= NEW_SECTION_H (nn
).sh_addr
-
1179 NEW_SECTION_H (nn
).sh_offset
;
1180 caddr_t reloc
= old_base
+ section
.sh_offset
, end
;
1181 for (end
= reloc
+ section
.sh_size
; reloc
< end
;
1182 reloc
+= section
.sh_entsize
)
1184 ElfW(Addr
) addr
= ((ElfW(Rel
) *) reloc
)->r_offset
- offset
;
1186 /* The Alpha ELF binutils currently have a bug that
1187 sometimes results in relocs that contain all
1188 zeroes. Work around this for now... */
1189 if (((ElfW(Rel
) *) reloc
)->r_offset
== 0)
1192 memcpy (new_base
+ addr
, old_base
+ addr
, sizeof(ElfW(Addr
)));
1199 /* Write out new_file, and free the buffers. */
1201 if (write (new_file
, new_base
, new_file_size
) != new_file_size
)
1202 fatal ("Didn't write %d bytes to %s: errno %d\n",
1203 new_file_size
, new_base
, errno
);
1208 /* Close the files and make the new file executable. */
1210 if (close (old_file
))
1211 fatal ("Can't close (%s): errno %d\n", old_name
, errno
);
1213 if (close (new_file
))
1214 fatal ("Can't close (%s): errno %d\n", new_name
, errno
);
1216 if (stat (new_name
, &stat_buf
) == -1)
1217 fatal ("Can't stat (%s): errno %d\n", new_name
, errno
);
1221 stat_buf
.st_mode
|= 0111 & ~n
;
1222 if (chmod (new_name
, stat_buf
.st_mode
) == -1)
1223 fatal ("Can't chmod (%s): errno %d\n", new_name
, errno
);