]>
code.delx.au - gnu-emacs/blob - src/unexelf.c
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 #include <sym.h> /* get COFF debugging symbol table declaration */
438 * NetBSD does not have normal-looking user-land ELF support.
445 # include <sys/exec_elf.h>
447 # define PT_LOAD Elf_pt_load
448 # define SHT_SYMTAB Elf_sht_symtab
449 # define SHT_DYNSYM Elf_sht_dynsym
450 # define SHT_NULL Elf_sht_null
451 # define SHT_NOBITS Elf_sht_nobits
452 # define SHT_REL Elf_sht_rel
453 # define SHT_RELA Elf_sht_rela
455 # define SHN_UNDEF Elf_eshn_undefined
456 # define SHN_ABS Elf_eshn_absolute
457 # define SHN_COMMON Elf_eshn_common
460 * The magic of picking the right size types is handled by the ELFSIZE
464 # define ElfW(type) Elf_##type
466 # define ElfW(type) Elf_/**/type
470 # include <sys/exec_ecoff.h>
471 # define HDRR struct ecoff_symhdr
472 # define pHDRR HDRR *
474 #endif /* __NetBSD__ */
477 # include <sys/exec_elf.h>
480 #if __GNU_LIBRARY__ - 0 >= 6
481 # include <link.h> /* get ElfW etc */
486 # define ElfW(type) Elf32_##type
488 # define ElfW(type) Elf32_/**/type
493 #define fatal(a, b, c) fprintf (stderr, a, b, c), exit (1)
496 extern void fatal (char *, ...);
499 #ifndef ELF_BSS_SECTION_NAME
500 #define ELF_BSS_SECTION_NAME ".bss"
503 /* Get the address of a particular section or program header entry,
504 * accounting for the size of the entries.
507 On PPC Reference Platform running Solaris 2.5.1
508 the plt section is also of type NOBI like the bss section.
509 (not really stored) and therefore sections after the bss
510 section start at the plt offset. The plt section is always
511 the one just before the bss section.
512 Thus, we modify the test from
513 if (NEW_SECTION_H (nn).sh_offset >= new_data2_offset)
515 if (NEW_SECTION_H (nn).sh_offset >=
516 OLD_SECTION_H (old_bss_index-1).sh_offset)
517 This is just a hack. We should put the new data section
518 before the .plt section.
519 And we should not have this routine at all but use
520 the libelf library to read the old file and create the new
522 The changed code is minimal and depends on prep set in m/prep.h
524 Quantum Theory Project
525 University of Florida
530 #define OLD_SECTION_H(n) \
531 (*(ElfW(Shdr) *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
532 #define NEW_SECTION_H(n) \
533 (*(ElfW(Shdr) *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
534 #define OLD_PROGRAM_H(n) \
535 (*(ElfW(Phdr) *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
536 #define NEW_PROGRAM_H(n) \
537 (*(ElfW(Phdr) *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
539 #define PATCH_INDEX(n) \
541 if ((int) (n) >= old_bss_index) \
543 typedef unsigned char byte
;
545 /* Round X up to a multiple of Y. */
557 /* ****************************************************************
562 * In ELF, this works by replacing the old .bss section with a new
563 * .data section, and inserting an empty .bss immediately afterwards.
567 unexec (new_name
, old_name
, data_start
, bss_start
, entry_address
)
568 char *new_name
, *old_name
;
569 unsigned data_start
, bss_start
, entry_address
;
571 int new_file
, old_file
, new_file_size
;
573 /* Pointers to the base of the image of the two files. */
574 caddr_t old_base
, new_base
;
576 /* Pointers to the file, program and section headers for the old and new
579 ElfW(Ehdr
) *old_file_h
, *new_file_h
;
580 ElfW(Phdr
) *old_program_h
, *new_program_h
;
581 ElfW(Shdr
) *old_section_h
, *new_section_h
;
583 /* Point to the section name table in the old file */
584 char *old_section_names
;
586 ElfW(Addr
) old_bss_addr
, new_bss_addr
;
587 ElfW(Word
) old_bss_size
, new_data2_size
;
588 ElfW(Off
) new_data2_offset
;
589 ElfW(Addr
) new_data2_addr
;
591 int n
, nn
, old_bss_index
, old_data_index
, new_data2_index
;
592 #if defined ( __sony_news) && defined (_SYSTYPE_SYSV)
593 int old_sbss_index
, old_mdebug_index
;
594 #endif /* __sony_news && _SYSTYPE_SYSV */
595 struct stat stat_buf
;
597 /* Open the old file & map it into the address space. */
599 old_file
= open (old_name
, O_RDONLY
);
602 fatal ("Can't open %s for reading: errno %d\n", old_name
, errno
);
604 if (fstat (old_file
, &stat_buf
) == -1)
605 fatal ("Can't fstat (%s): errno %d\n", old_name
, errno
);
607 old_base
= mmap ((caddr_t
) 0, stat_buf
.st_size
, PROT_READ
, MAP_SHARED
,
610 if (old_base
== (caddr_t
) -1)
611 fatal ("Can't mmap (%s): errno %d\n", old_name
, errno
);
614 fprintf (stderr
, "mmap (%s, %x) -> %x\n", old_name
, stat_buf
.st_size
,
618 /* Get pointers to headers & section names */
620 old_file_h
= (ElfW(Ehdr
) *) old_base
;
621 old_program_h
= (ElfW(Phdr
) *) ((byte
*) old_base
+ old_file_h
->e_phoff
);
622 old_section_h
= (ElfW(Shdr
) *) ((byte
*) old_base
+ old_file_h
->e_shoff
);
623 old_section_names
= (char *) old_base
624 + OLD_SECTION_H (old_file_h
->e_shstrndx
).sh_offset
;
626 /* Find the old .bss section. Figure out parameters of the new
627 * data2 and bss sections.
630 for (old_bss_index
= 1; old_bss_index
< (int) old_file_h
->e_shnum
;
634 fprintf (stderr
, "Looking for .bss - found %s\n",
635 old_section_names
+ OLD_SECTION_H (old_bss_index
).sh_name
);
637 if (!strcmp (old_section_names
+ OLD_SECTION_H (old_bss_index
).sh_name
,
638 ELF_BSS_SECTION_NAME
))
641 if (old_bss_index
== old_file_h
->e_shnum
)
642 fatal ("Can't find .bss in %s.\n", old_name
, 0);
644 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
645 for (old_sbss_index
= 1; old_sbss_index
< (int) old_file_h
->e_shnum
;
649 fprintf (stderr
, "Looking for .sbss - found %s\n",
650 old_section_names
+ OLD_SECTION_H (old_sbss_index
).sh_name
);
652 if (!strcmp (old_section_names
+ OLD_SECTION_H (old_sbss_index
).sh_name
,
656 if (old_sbss_index
== old_file_h
->e_shnum
)
658 old_bss_addr
= OLD_SECTION_H(old_bss_index
).sh_addr
;
659 old_bss_size
= OLD_SECTION_H(old_bss_index
).sh_size
;
660 new_data2_offset
= OLD_SECTION_H(old_bss_index
).sh_offset
;
661 new_data2_index
= old_bss_index
;
665 old_bss_addr
= OLD_SECTION_H(old_sbss_index
).sh_addr
;
666 old_bss_size
= OLD_SECTION_H(old_bss_index
).sh_size
667 + OLD_SECTION_H(old_sbss_index
).sh_size
;
668 new_data2_offset
= OLD_SECTION_H(old_sbss_index
).sh_offset
;
669 new_data2_index
= old_sbss_index
;
672 for (old_mdebug_index
= 1; old_mdebug_index
< (int) old_file_h
->e_shnum
;
676 fprintf (stderr
, "Looking for .mdebug - found %s\n",
677 old_section_names
+ OLD_SECTION_H (old_mdebug_index
).sh_name
);
679 if (!strcmp (old_section_names
+ OLD_SECTION_H (old_mdebug_index
).sh_name
,
683 if (old_mdebug_index
== old_file_h
->e_shnum
)
684 old_mdebug_index
= 0;
685 #else /* not (__sony_news && _SYSTYPE_SYSV) */
686 old_bss_addr
= OLD_SECTION_H (old_bss_index
).sh_addr
;
687 old_bss_size
= OLD_SECTION_H (old_bss_index
).sh_size
;
688 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
689 #if defined (emacs) || !defined (DEBUG)
690 new_bss_addr
= (ElfW(Addr
)) sbrk (0);
692 new_bss_addr
= old_bss_addr
+ old_bss_size
+ 0x1234;
694 new_data2_addr
= old_bss_addr
;
695 new_data2_size
= new_bss_addr
- old_bss_addr
;
696 #if !defined (__sony_news) || !defined (_SYSTYPE_SYSV)
697 new_data2_offset
= OLD_SECTION_H (old_bss_index
).sh_offset
;
698 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
701 fprintf (stderr
, "old_bss_index %d\n", old_bss_index
);
702 fprintf (stderr
, "old_bss_addr %x\n", old_bss_addr
);
703 fprintf (stderr
, "old_bss_size %x\n", old_bss_size
);
704 fprintf (stderr
, "new_bss_addr %x\n", new_bss_addr
);
705 fprintf (stderr
, "new_data2_addr %x\n", new_data2_addr
);
706 fprintf (stderr
, "new_data2_size %x\n", new_data2_size
);
707 fprintf (stderr
, "new_data2_offset %x\n", new_data2_offset
);
710 if ((unsigned) new_bss_addr
< (unsigned) old_bss_addr
+ old_bss_size
)
711 fatal (".bss shrank when undumping???\n", 0, 0);
713 /* Set the output file to the right size and mmap it. Set
714 * pointers to various interesting objects. stat_buf still has
718 new_file
= open (new_name
, O_RDWR
| O_CREAT
, 0666);
720 fatal ("Can't creat (%s): errno %d\n", new_name
, errno
);
722 new_file_size
= stat_buf
.st_size
+ old_file_h
->e_shentsize
+ new_data2_size
;
724 if (ftruncate (new_file
, new_file_size
))
725 fatal ("Can't ftruncate (%s): errno %d\n", new_name
, errno
);
727 #ifdef UNEXEC_USE_MAP_PRIVATE
728 new_base
= mmap ((caddr_t
) 0, new_file_size
, PROT_READ
| PROT_WRITE
,
729 MAP_PRIVATE
, new_file
, 0);
731 new_base
= mmap ((caddr_t
) 0, new_file_size
, PROT_READ
| PROT_WRITE
,
732 MAP_SHARED
, new_file
, 0);
735 if (new_base
== (caddr_t
) -1)
736 fatal ("Can't mmap (%s): errno %d\n", new_name
, errno
);
738 new_file_h
= (ElfW(Ehdr
) *) new_base
;
739 new_program_h
= (ElfW(Phdr
) *) ((byte
*) new_base
+ old_file_h
->e_phoff
);
740 new_section_h
= (ElfW(Shdr
) *)
741 ((byte
*) new_base
+ old_file_h
->e_shoff
+ new_data2_size
);
743 /* Make our new file, program and section headers as copies of the
747 memcpy (new_file_h
, old_file_h
, old_file_h
->e_ehsize
);
748 memcpy (new_program_h
, old_program_h
,
749 old_file_h
->e_phnum
* old_file_h
->e_phentsize
);
751 /* Modify the e_shstrndx if necessary. */
752 PATCH_INDEX (new_file_h
->e_shstrndx
);
754 /* Fix up file header. We'll add one section. Section header is
758 new_file_h
->e_shoff
+= new_data2_size
;
759 new_file_h
->e_shnum
+= 1;
762 fprintf (stderr
, "Old section offset %x\n", old_file_h
->e_shoff
);
763 fprintf (stderr
, "Old section count %d\n", old_file_h
->e_shnum
);
764 fprintf (stderr
, "New section offset %x\n", new_file_h
->e_shoff
);
765 fprintf (stderr
, "New section count %d\n", new_file_h
->e_shnum
);
768 /* Fix up a new program header. Extend the writable data segment so
769 * that the bss area is covered too. Find that segment by looking
770 * for a segment that ends just before the .bss area. Make sure
771 * that no segments are above the new .data2. Put a loop at the end
772 * to adjust the offset and address of any segment that is above
773 * data2, just in case we decide to allow this later.
776 for (n
= new_file_h
->e_phnum
- 1; n
>= 0; n
--)
778 /* Compute maximum of all requirements for alignment of section. */
779 int alignment
= (NEW_PROGRAM_H (n
)).p_align
;
780 if ((OLD_SECTION_H (old_bss_index
)).sh_addralign
> alignment
)
781 alignment
= OLD_SECTION_H (old_bss_index
).sh_addralign
;
783 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
784 if (NEW_PROGRAM_H (n
).p_vaddr
+ NEW_PROGRAM_H (n
).p_filesz
785 > round_up (old_bss_addr
, alignment
))
786 fatal ("Program segment above .bss in %s\n", old_name
, 0);
787 #else /* not (__sony_news && _SYSTYPE_SYSV) */
788 if (NEW_PROGRAM_H (n
).p_vaddr
+ NEW_PROGRAM_H (n
).p_filesz
> old_bss_addr
)
789 fatal ("Program segment above .bss in %s\n", old_name
, 0);
790 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
792 if (NEW_PROGRAM_H (n
).p_type
== PT_LOAD
793 && (round_up ((NEW_PROGRAM_H (n
)).p_vaddr
794 + (NEW_PROGRAM_H (n
)).p_filesz
,
796 == round_up (old_bss_addr
, alignment
)))
800 fatal ("Couldn't find segment next to .bss in %s\n", old_name
, 0);
802 NEW_PROGRAM_H (n
).p_filesz
+= new_data2_size
;
803 NEW_PROGRAM_H (n
).p_memsz
= NEW_PROGRAM_H (n
).p_filesz
;
805 #if 0 /* Maybe allow section after data2 - does this ever happen? */
806 for (n
= new_file_h
->e_phnum
- 1; n
>= 0; n
--)
808 if (NEW_PROGRAM_H (n
).p_vaddr
809 && NEW_PROGRAM_H (n
).p_vaddr
>= new_data2_addr
)
810 NEW_PROGRAM_H (n
).p_vaddr
+= new_data2_size
- old_bss_size
;
812 if (NEW_PROGRAM_H (n
).p_offset
>= new_data2_offset
)
813 NEW_PROGRAM_H (n
).p_offset
+= new_data2_size
;
817 /* Fix up section headers based on new .data2 section. Any section
818 * whose offset or virtual address is after the new .data2 section
819 * gets its value adjusted. .bss size becomes zero and new address
820 * is set. data2 section header gets added by copying the existing
821 * .data header and modifying the offset, address and size.
823 for (old_data_index
= 1; old_data_index
< (int) old_file_h
->e_shnum
;
825 if (!strcmp (old_section_names
+ OLD_SECTION_H (old_data_index
).sh_name
,
828 if (old_data_index
== old_file_h
->e_shnum
)
829 fatal ("Can't find .data in %s.\n", old_name
, 0);
831 /* Walk through all section headers, insert the new data2 section right
832 before the new bss section. */
833 for (n
= 1, nn
= 1; n
< (int) old_file_h
->e_shnum
; n
++, nn
++)
837 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
838 /* If it is (s)bss section, insert the new data2 section before it. */
839 /* new_data2_index is the index of either old_sbss or old_bss, that was
840 chosen as a section for new_data2. */
841 temp_index
= new_data2_index
;
842 #else /* not (__sony_news && _SYSTYPE_SYSV) */
843 /* If it is bss section, insert the new data2 section before it. */
844 temp_index
= old_bss_index
;
845 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
848 /* Steal the data section header for this data2 section. */
849 memcpy (&NEW_SECTION_H (nn
), &OLD_SECTION_H (old_data_index
),
850 new_file_h
->e_shentsize
);
852 NEW_SECTION_H (nn
).sh_addr
= new_data2_addr
;
853 NEW_SECTION_H (nn
).sh_offset
= new_data2_offset
;
854 NEW_SECTION_H (nn
).sh_size
= new_data2_size
;
855 /* Use the bss section's alignment. This will assure that the
856 new data2 section always be placed in the same spot as the old
857 bss section by any other application. */
858 NEW_SECTION_H (nn
).sh_addralign
= OLD_SECTION_H (n
).sh_addralign
;
860 /* Now copy over what we have in the memory now. */
861 memcpy (NEW_SECTION_H (nn
).sh_offset
+ new_base
,
862 (caddr_t
) OLD_SECTION_H (n
).sh_addr
,
867 memcpy (&NEW_SECTION_H (nn
), &OLD_SECTION_H (n
),
868 old_file_h
->e_shentsize
);
870 if (n
== old_bss_index
871 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
872 /* The new bss and sbss section's size is zero, and its file offset
873 and virtual address should be off by NEW_DATA2_SIZE. */
874 || n
== old_sbss_index
875 #endif /* __sony_news and _SYSTYPE_SYSV */
878 /* NN should be `old_bss_index + 1' at this point. */
879 NEW_SECTION_H (nn
).sh_offset
+= new_data2_size
;
880 NEW_SECTION_H (nn
).sh_addr
+= new_data2_size
;
881 /* Let the new bss section address alignment be the same as the
882 section address alignment followed the old bss section, so
883 this section will be placed in exactly the same place. */
884 NEW_SECTION_H (nn
).sh_addralign
= OLD_SECTION_H (nn
).sh_addralign
;
885 NEW_SECTION_H (nn
).sh_size
= 0;
889 /* Any section that was original placed AFTER the bss
890 section should now be off by NEW_DATA2_SIZE. */
891 #ifdef SOLARIS_POWERPC
892 /* On PPC Reference Platform running Solaris 2.5.1
893 the plt section is also of type NOBI like the bss section.
894 (not really stored) and therefore sections after the bss
895 section start at the plt offset. The plt section is always
896 the one just before the bss section.
897 It would be better to put the new data section before
898 the .plt section, or use libelf instead.
899 Erik Deumens, deumens@qtp.ufl.edu. */
900 if (NEW_SECTION_H (nn
).sh_offset
901 >= OLD_SECTION_H (old_bss_index
-1).sh_offset
)
902 NEW_SECTION_H (nn
).sh_offset
+= new_data2_size
;
904 if (round_up (NEW_SECTION_H (nn
).sh_offset
,
905 OLD_SECTION_H (old_bss_index
).sh_addralign
)
907 NEW_SECTION_H (nn
).sh_offset
+= new_data2_size
;
909 /* Any section that was originally placed after the section
910 header table should now be off by the size of one section
911 header table entry. */
912 if (NEW_SECTION_H (nn
).sh_offset
> new_file_h
->e_shoff
)
913 NEW_SECTION_H (nn
).sh_offset
+= new_file_h
->e_shentsize
;
916 /* If any section hdr refers to the section after the new .data
917 section, make it refer to next one because we have inserted
918 a new section in between. */
920 PATCH_INDEX (NEW_SECTION_H (nn
).sh_link
);
921 /* For symbol tables, info is a symbol table index,
922 so don't change it. */
923 if (NEW_SECTION_H (nn
).sh_type
!= SHT_SYMTAB
924 && NEW_SECTION_H (nn
).sh_type
!= SHT_DYNSYM
)
925 PATCH_INDEX (NEW_SECTION_H (nn
).sh_info
);
927 /* Now, start to copy the content of sections. */
928 if (NEW_SECTION_H (nn
).sh_type
== SHT_NULL
929 || NEW_SECTION_H (nn
).sh_type
== SHT_NOBITS
)
932 /* Write out the sections. .data and .data1 (and data2, called
933 ".data" in the strings table) get copied from the current process
934 instead of the old file. */
935 if (!strcmp (old_section_names
+ NEW_SECTION_H (n
).sh_name
, ".data")
936 #ifdef _nec_ews_svr4 /* hir, 1994.6.13 */
937 || !strcmp ((old_section_names
+ NEW_SECTION_H(n
).sh_name
),
940 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
941 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
943 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
945 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
947 #endif /* __sony_news && _SYSTYPE_SYSV */
948 || !strcmp ((old_section_names
+ NEW_SECTION_H (n
).sh_name
),
950 src
= (caddr_t
) OLD_SECTION_H (n
).sh_addr
;
952 src
= old_base
+ OLD_SECTION_H (n
).sh_offset
;
954 memcpy (NEW_SECTION_H (nn
).sh_offset
+ new_base
, src
,
955 NEW_SECTION_H (nn
).sh_size
);
958 /* Update Alpha COFF symbol table: */
959 if (strcmp (old_section_names
+ OLD_SECTION_H (n
).sh_name
, ".mdebug")
962 pHDRR symhdr
= (pHDRR
) (NEW_SECTION_H (nn
).sh_offset
+ new_base
);
964 symhdr
->cbLineOffset
+= new_data2_size
;
965 symhdr
->cbDnOffset
+= new_data2_size
;
966 symhdr
->cbPdOffset
+= new_data2_size
;
967 symhdr
->cbSymOffset
+= new_data2_size
;
968 symhdr
->cbOptOffset
+= new_data2_size
;
969 symhdr
->cbAuxOffset
+= new_data2_size
;
970 symhdr
->cbSsOffset
+= new_data2_size
;
971 symhdr
->cbSsExtOffset
+= new_data2_size
;
972 symhdr
->cbFdOffset
+= new_data2_size
;
973 symhdr
->cbRfdOffset
+= new_data2_size
;
974 symhdr
->cbExtOffset
+= new_data2_size
;
976 #endif /* __alpha__ */
978 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
979 if (NEW_SECTION_H (nn
).sh_type
== SHT_MIPS_DEBUG
&& old_mdebug_index
)
981 int diff
= NEW_SECTION_H(nn
).sh_offset
982 - OLD_SECTION_H(old_mdebug_index
).sh_offset
;
983 HDRR
*phdr
= (HDRR
*)(NEW_SECTION_H (nn
).sh_offset
+ new_base
);
987 phdr
->cbLineOffset
+= diff
;
988 phdr
->cbDnOffset
+= diff
;
989 phdr
->cbPdOffset
+= diff
;
990 phdr
->cbSymOffset
+= diff
;
991 phdr
->cbOptOffset
+= diff
;
992 phdr
->cbAuxOffset
+= diff
;
993 phdr
->cbSsOffset
+= diff
;
994 phdr
->cbSsExtOffset
+= diff
;
995 phdr
->cbFdOffset
+= diff
;
996 phdr
->cbRfdOffset
+= diff
;
997 phdr
->cbExtOffset
+= diff
;
1000 #endif /* __sony_news && _SYSTYPE_SYSV */
1001 /* If it is the symbol table, its st_shndx field needs to be patched. */
1002 if (NEW_SECTION_H (nn
).sh_type
== SHT_SYMTAB
1003 || NEW_SECTION_H (nn
).sh_type
== SHT_DYNSYM
)
1005 ElfW(Shdr
) *spt
= &NEW_SECTION_H (nn
);
1006 unsigned int num
= spt
->sh_size
/ spt
->sh_entsize
;
1007 ElfW(Sym
) * sym
= (ElfW(Sym
) *) (NEW_SECTION_H (nn
).sh_offset
+
1009 for (; num
--; sym
++)
1011 if ((sym
->st_shndx
== SHN_UNDEF
)
1012 || (sym
->st_shndx
== SHN_ABS
)
1013 || (sym
->st_shndx
== SHN_COMMON
))
1016 PATCH_INDEX (sym
->st_shndx
);
1021 /* Update the symbol values of _edata and _end. */
1022 for (n
= new_file_h
->e_shnum
- 1; n
; n
--)
1025 ElfW(Sym
) *symp
, *symendp
;
1027 if (NEW_SECTION_H (n
).sh_type
!= SHT_DYNSYM
1028 && NEW_SECTION_H (n
).sh_type
!= SHT_SYMTAB
)
1031 symnames
= ((byte
*) new_base
1032 + NEW_SECTION_H (NEW_SECTION_H (n
).sh_link
).sh_offset
);
1033 symp
= (ElfW(Sym
) *) (NEW_SECTION_H (n
).sh_offset
+ new_base
);
1034 symendp
= (ElfW(Sym
) *) ((byte
*)symp
+ NEW_SECTION_H (n
).sh_size
);
1036 for (; symp
< symendp
; symp
++)
1037 if (strcmp ((char *) (symnames
+ symp
->st_name
), "_end") == 0
1038 || strcmp ((char *) (symnames
+ symp
->st_name
), "_edata") == 0)
1039 memcpy (&symp
->st_value
, &new_bss_addr
, sizeof (new_bss_addr
));
1042 /* This loop seeks out relocation sections for the data section, so
1043 that it can undo relocations performed by the runtime linker. */
1044 for (n
= new_file_h
->e_shnum
- 1; n
; n
--)
1046 ElfW(Shdr
) section
= NEW_SECTION_H (n
);
1047 switch (section
.sh_type
) {
1052 /* This code handles two different size structs, but there should
1053 be no harm in that provided that r_offset is always the first
1055 nn
= section
.sh_info
;
1056 if (!strcmp (old_section_names
+ NEW_SECTION_H (nn
).sh_name
, ".data")
1057 || !strcmp ((old_section_names
+ NEW_SECTION_H (nn
).sh_name
),
1060 ElfW(Addr
) offset
= NEW_SECTION_H (nn
).sh_addr
-
1061 NEW_SECTION_H (nn
).sh_offset
;
1062 caddr_t reloc
= old_base
+ section
.sh_offset
, end
;
1063 for (end
= reloc
+ section
.sh_size
; reloc
< end
;
1064 reloc
+= section
.sh_entsize
)
1066 ElfW(Addr
) addr
= ((ElfW(Rel
) *) reloc
)->r_offset
- offset
;
1068 /* The Alpha ELF binutils currently have a bug that
1069 sometimes results in relocs that contain all
1070 zeroes. Work around this for now... */
1071 if (((ElfW(Rel
) *) reloc
)->r_offset
== 0)
1074 memcpy (new_base
+ addr
, old_base
+ addr
, sizeof(ElfW(Addr
)));
1081 #ifdef UNEXEC_USE_MAP_PRIVATE
1082 if (lseek (new_file
, 0, SEEK_SET
) == -1)
1083 fatal ("Can't rewind (%s): errno %d\n", new_name
, errno
);
1085 if (write (new_file
, new_base
, new_file_size
) != new_file_size
)
1086 fatal ("Can't write (%s): errno %d\n", new_name
, errno
);
1089 /* Close the files and make the new file executable. */
1091 if (close (old_file
))
1092 fatal ("Can't close (%s): errno %d\n", old_name
, errno
);
1094 if (close (new_file
))
1095 fatal ("Can't close (%s): errno %d\n", new_name
, errno
);
1097 if (stat (new_name
, &stat_buf
) == -1)
1098 fatal ("Can't stat (%s): errno %d\n", new_name
, errno
);
1102 stat_buf
.st_mode
|= 0111 & ~n
;
1103 if (chmod (new_name
, stat_buf
.st_mode
) == -1)
1104 fatal ("Can't chmod (%s): errno %d\n", new_name
, errno
);