1 /* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992, 1993
2 Free Software Foundation, Inc.
4 This file is part of XEmacs.
6 XEmacs is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by the
8 Free Software Foundation; either version 2, or (at your option) any
11 XEmacs is distributed in the hope that it will be useful, but WITHOUT
12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with XEmacs; see the file COPYING. If not, write to
18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
21 /* Synched up with: FSF 20.4. */
24 * unexec.c - Convert a running program into an a.out file.
26 * Author: Spencer W. Thomas
27 * Computer Science Dept.
29 * Date: Tue Mar 2 1982
30 * Modified heavily since then.
33 * unexec (new_name, a_name, data_start, bss_start, entry_address)
34 * char *new_name, *a_name;
35 * unsigned data_start, bss_start, entry_address;
37 * Takes a snapshot of the program and makes an a.out format file in the
38 * file named by the string argument new_name.
39 * If a_name is non-NULL, the symbol table will be taken from the given file.
40 * On some machines, an existing a_name file is required.
42 * The boundaries within the a.out file may be adjusted with the data_start
43 * and bss_start arguments. Either or both may be given as 0 for defaults.
45 * Data_start gives the boundary between the text segment and the data
46 * segment of the program. The text segment can contain shared, read-only
47 * program code and literal data, while the data segment is always unshared
48 * and unprotected. Data_start gives the lowest unprotected address.
49 * The value you specify may be rounded down to a suitable boundary
50 * as required by the machine you are using.
52 * Specifying zero for data_start means the boundary between text and data
53 * should not be the same as when the program was loaded.
54 * If NO_REMAP is defined, the argument data_start is ignored and the
55 * segment boundaries are never changed.
57 * Bss_start indicates how much of the data segment is to be saved in the
58 * a.out file and restored when the program is executed. It gives the lowest
59 * unsaved address, and is rounded up to a page boundary. The default when 0
60 * is given assumes that the entire data segment is to be stored, including
61 * the previous data and bss as well as any additional storage allocated with
64 * The new file is set up to start at entry_address.
66 * If you make improvements I'd like to get them too.
67 * harpo!utah-cs!thomas, thomas@Utah-20
71 /* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
74 * Basic theory: the data space of the running process needs to be
75 * dumped to the output file. Normally we would just enlarge the size
76 * of .data, scooting everything down. But we can't do that in ELF,
77 * because there is often something between the .data space and the
80 * In the temacs dump below, notice that the Global Offset Table
81 * (.got) and the Dynamic link data (.dynamic) come between .data1 and
82 * .bss. It does not work to overlap .data with these fields.
84 * The solution is to create a new .data segment. This segment is
85 * filled with data from the current process. Since the contents of
86 * various sections refer to sections by index, the new .data segment
87 * is made the last in the table to avoid changing any existing index.
89 * This is an example of how the section headers are changed. "Addr"
90 * is a process virtual address. "Offset" is a file offset.
92 raid:/nfs/raid/src/dist-18.56/src> dump -h temacs
96 **** SECTION HEADER TABLE ****
97 [No] Type Flags Addr Offset Size Name
98 Link Info Adralgn Entsize
100 [1] 1 2 0x80480d4 0xd4 0x13 .interp
103 [2] 5 2 0x80480e8 0xe8 0x388 .hash
106 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
109 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
112 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
115 [6] 1 6 0x8049348 0x1348 0x3 .init
118 [7] 1 6 0x804934c 0x134c 0x680 .plt
121 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
124 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
127 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
130 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
133 [12] 1 3 0x8088330 0x3f330 0x20afc .data
136 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
139 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
142 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
145 [16] 8 3 0x80a98f4 0x608f4 0x449c .bss
148 [17] 2 0 0 0x608f4 0x9b90 .symtab
151 [18] 3 0 0 0x6a484 0x8526 .strtab
154 [19] 3 0 0 0x729aa 0x93 .shstrtab
157 [20] 1 0 0 0x72a3d 0x68b7 .comment
160 raid:/nfs/raid/src/dist-18.56/src> dump -h xemacs
164 **** SECTION HEADER TABLE ****
165 [No] Type Flags Addr Offset Size Name
166 Link Info Adralgn Entsize
168 [1] 1 2 0x80480d4 0xd4 0x13 .interp
171 [2] 5 2 0x80480e8 0xe8 0x388 .hash
174 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
177 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
180 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
183 [6] 1 6 0x8049348 0x1348 0x3 .init
186 [7] 1 6 0x804934c 0x134c 0x680 .plt
189 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
192 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
195 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
198 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
201 [12] 1 3 0x8088330 0x3f330 0x20afc .data
204 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
207 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
210 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
213 [16] 8 3 0x80c6800 0x7d800 0 .bss
216 [17] 2 0 0 0x7d800 0x9b90 .symtab
219 [18] 3 0 0 0x87390 0x8526 .strtab
222 [19] 3 0 0 0x8f8b6 0x93 .shstrtab
225 [20] 1 0 0 0x8f949 0x68b7 .comment
228 [21] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
231 * This is an example of how the file header is changed. "Shoff" is
232 * the section header offset within the file. Since that table is
233 * after the new .data section, it is moved. "Shnum" is the number of
234 * sections, which we increment.
236 * "Phoff" is the file offset to the program header. "Phentsize" and
237 * "Shentsz" are the program and section header entries sizes respectively.
238 * These can be larger than the apparent struct sizes.
240 raid:/nfs/raid/src/dist-18.56/src> dump -f temacs
245 Class Data Type Machine Version
246 Entry Phoff Shoff Flags Ehsize
247 Phentsize Phnum Shentsz Shnum Shstrndx
250 0x80499cc 0x34 0x792f4 0 0x34
253 raid:/nfs/raid/src/dist-18.56/src> dump -f xemacs
258 Class Data Type Machine Version
259 Entry Phoff Shoff Flags Ehsize
260 Phentsize Phnum Shentsz Shnum Shstrndx
263 0x80499cc 0x34 0x96200 0 0x34
266 * These are the program headers. "Offset" is the file offset to the
267 * segment. "Vaddr" is the memory load address. "Filesz" is the
268 * segment size as it appears in the file, and "Memsz" is the size in
269 * memory. Below, the third segment is the code and the fourth is the
270 * data: the difference between Filesz and Memsz is .bss
272 raid:/nfs/raid/src/dist-18.56/src> dump -o temacs
275 ***** PROGRAM EXECUTION HEADER *****
276 Type Offset Vaddr Paddr
277 Filesz Memsz Flags Align
286 0x3f2f9 0x3f2f9 5 0x1000
288 1 0x3f330 0x8088330 0
289 0x215c4 0x25a60 7 0x1000
291 2 0x60874 0x80a9874 0
294 raid:/nfs/raid/src/dist-18.56/src> dump -o xemacs
297 ***** PROGRAM EXECUTION HEADER *****
298 Type Offset Vaddr Paddr
299 Filesz Memsz Flags Align
308 0x3f2f9 0x3f2f9 5 0x1000
310 1 0x3f330 0x8088330 0
311 0x3e4d0 0x3e4d0 7 0x1000
313 2 0x60874 0x80a9874 0
319 /* Modified by wtien@urbana.mcd.mot.com of Motorola Inc.
321 * The above mechanism does not work if the unexeced ELF file is being
322 * re-layout by other applications (such as `strip'). All the applications
323 * that re-layout the internal of ELF will layout all sections in ascending
324 * order of their file offsets. After the re-layout, the data2 section will
325 * still be the LAST section in the section header vector, but its file offset
326 * is now being pushed far away down, and causes part of it not to be mapped
327 * in (ie. not covered by the load segment entry in PHDR vector), therefore
328 * causes the new binary to fail.
330 * The solution is to modify the unexec algorithm to insert the new data2
331 * section header right before the new bss section header, so their file
332 * offsets will be in the ascending order. Since some of the section's (all
333 * sections AFTER the bss section) indexes are now changed, we also need to
334 * modify some fields to make them point to the right sections. This is done
335 * by macro PATCH_INDEX. All the fields that need to be patched are:
337 * 1. ELF header e_shstrndx field.
338 * 2. section header sh_link and sh_info field.
339 * 3. symbol table entry st_shndx field.
341 * The above example now should look like:
343 **** SECTION HEADER TABLE ****
344 [No] Type Flags Addr Offset Size Name
345 Link Info Adralgn Entsize
347 [1] 1 2 0x80480d4 0xd4 0x13 .interp
350 [2] 5 2 0x80480e8 0xe8 0x388 .hash
353 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
356 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
359 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
362 [6] 1 6 0x8049348 0x1348 0x3 .init
365 [7] 1 6 0x804934c 0x134c 0x680 .plt
368 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
371 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
374 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
377 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
380 [12] 1 3 0x8088330 0x3f330 0x20afc .data
383 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
386 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
389 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
392 [16] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
395 [17] 8 3 0x80c6800 0x7d800 0 .bss
398 [18] 2 0 0 0x7d800 0x9b90 .symtab
401 [19] 3 0 0 0x87390 0x8526 .strtab
404 [20] 3 0 0 0x8f8b6 0x93 .shstrtab
407 [21] 1 0 0 0x8f949 0x68b7 .comment
413 #define fatal(a, b, c) fprintf (stderr, a, b, c), exit (1)
416 extern void fatal (const char *, ...);
419 #include <sys/types.h>
421 #include <sys/stat.h>
430 #include <sys/mman.h>
431 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
432 #include <sys/elf_mips.h>
434 #endif /* __sony_news && _SYSTYPE_SYSV */
436 #include <sym.h> /* for HDRR declaration */
439 #if defined (__alpha__) && !defined (__NetBSD__) && !defined (__OpenBSD__)
440 /* Declare COFF debugging symbol table. This used to be in
441 /usr/include/sym.h, but this file is no longer included in Red Hat
442 5.0 and presumably in any other glibc 2.x based distribution. */
470 #define cbHDRR sizeof(HDRR)
471 #define hdrNil ((pHDRR)0)
476 * NetBSD does not have normal-looking user-land ELF support.
483 # include <sys/exec_elf.h>
485 # define PT_LOAD Elf_pt_load
486 # define SHT_SYMTAB Elf_sht_symtab
487 # define SHT_DYNSYM Elf_sht_dynsym
488 # define SHT_NULL Elf_sht_null
489 # define SHT_NOBITS Elf_sht_nobits
490 # define SHT_REL Elf_sht_rel
491 # define SHT_RELA Elf_sht_rela
493 # define SHN_UNDEF Elf_eshn_undefined
494 # define SHN_ABS Elf_eshn_absolute
495 # define SHN_COMMON Elf_eshn_common
498 # include <sys/exec_ecoff.h>
499 # define HDRR struct ecoff_symhdr
500 # define pHDRR HDRR *
502 #endif /* __NetBSD__ */
505 # include <sys/exec_elf.h>
508 #if __GNU_LIBRARY__ - 0 >= 6
509 # include <link.h> /* get ElfW etc */
514 # define ElfW(type) Elf32_##type
516 # define ElfW(type) Elf32_/**/type
520 #ifndef ELF_BSS_SECTION_NAME
521 #define ELF_BSS_SECTION_NAME ".bss"
524 /* Get the address of a particular section or program header entry,
525 * accounting for the size of the entries.
528 On PPC Reference Platform running Solaris 2.5.1
529 the plt section is also of type NOBI like the bss section.
530 (not really stored) and therefore sections after the bss
531 section start at the plt offset. The plt section is always
532 the one just before the bss section.
533 Thus, we modify the test from
534 if (NEW_SECTION_H (nn).sh_offset >= new_data2_offset)
536 if (NEW_SECTION_H (nn).sh_offset >=
537 OLD_SECTION_H (old_bss_index-1).sh_offset)
538 This is just a hack. We should put the new data section
539 before the .plt section.
540 And we should not have this routine at all but use
541 the libelf library to read the old file and create the new
543 The changed code is minimal and depends on prep set in m/prep.h
545 Quantum Theory Project
546 University of Florida
551 #define OLD_SECTION_H(n) \
552 (*(ElfW(Shdr) *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
553 #define NEW_SECTION_H(n) \
554 (*(ElfW(Shdr) *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
555 #define OLD_PROGRAM_H(n) \
556 (*(ElfW(Phdr) *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
557 #define NEW_PROGRAM_H(n) \
558 (*(ElfW(Phdr) *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
560 #define PATCH_INDEX(n) \
562 if ((int) (n) >= old_bss_index) \
564 typedef unsigned char byte;
566 /* Round X up to a multiple of Y. */
569 round_up (ElfW(Addr) x, ElfW(Addr) y)
577 /* ****************************************************************
582 * In ELF, this works by replacing the old .bss section with a new
583 * .data section, and inserting an empty .bss immediately afterwards.
586 void unexec (char *new_name, char *old_name, unsigned int data_start,
587 unsigned int bss_start, unsigned int entry_address);
589 unexec (char *new_name, char *old_name, unsigned int data_start,
590 unsigned int bss_start, unsigned int entry_address)
592 int new_file, old_file, new_file_size;
594 /* Pointers to the base of the image of the two files. */
595 caddr_t old_base, new_base;
597 /* Pointers to the file, program and section headers for the old and new
600 ElfW(Ehdr) *old_file_h, *new_file_h;
601 ElfW(Phdr) *old_program_h, *new_program_h;
602 ElfW(Shdr) *old_section_h, *new_section_h;
604 /* Point to the section name table in the old file */
605 char *old_section_names;
607 ElfW(Addr) old_bss_addr, new_bss_addr;
608 ElfW(Word) old_bss_size, new_data2_size;
609 ElfW(Off) new_data2_offset;
610 ElfW(Addr) new_data2_addr;
612 int n, nn, old_bss_index, old_data_index, new_data2_index;
613 int old_sbss_index, old_mdebug_index;
614 struct stat stat_buf;
616 /* Open the old file & map it into the address space. */
618 old_file = open (old_name, O_RDONLY);
621 fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
623 if (fstat (old_file, &stat_buf) == -1)
624 fatal ("Can't fstat (%s): errno %d\n", old_name, errno);
626 old_base = (caddr_t) mmap (0, stat_buf.st_size, PROT_READ, MAP_SHARED, old_file, 0);
628 if (old_base == (caddr_t) -1)
629 fatal ("Can't mmap (%s): errno %d\n", old_name, errno);
632 fprintf (stderr, "mmap (%s, %x) -> %x\n", old_name, stat_buf.st_size,
636 /* Get pointers to headers & section names */
638 old_file_h = (ElfW(Ehdr) *) old_base;
639 old_program_h = (ElfW(Phdr) *) ((byte *) old_base + old_file_h->e_phoff);
640 old_section_h = (ElfW(Shdr) *) ((byte *) old_base + old_file_h->e_shoff);
641 old_section_names = (char *) old_base
642 + OLD_SECTION_H (old_file_h->e_shstrndx).sh_offset;
644 /* Find the old .bss section. Figure out parameters of the new
645 * data2 and bss sections.
648 for (old_bss_index = 1; old_bss_index < (int) old_file_h->e_shnum;
652 fprintf (stderr, "Looking for .bss - found %s\n",
653 old_section_names + OLD_SECTION_H (old_bss_index).sh_name);
655 if (!strcmp (old_section_names + OLD_SECTION_H (old_bss_index).sh_name,
656 ELF_BSS_SECTION_NAME))
659 if (old_bss_index == old_file_h->e_shnum)
660 fatal ("Can't find .bss in %s.\n", old_name, 0);
662 for (old_sbss_index = 1; old_sbss_index < (int) old_file_h->e_shnum;
666 fprintf (stderr, "Looking for .sbss - found %s\n",
667 old_section_names + OLD_SECTION_H (old_sbss_index).sh_name);
669 if (!strcmp (old_section_names + OLD_SECTION_H (old_sbss_index).sh_name,
673 if (old_sbss_index == old_file_h->e_shnum)
676 old_bss_addr = OLD_SECTION_H(old_bss_index).sh_addr;
677 old_bss_size = OLD_SECTION_H(old_bss_index).sh_size;
678 new_data2_index = old_bss_index;
682 old_bss_addr = OLD_SECTION_H(old_sbss_index).sh_addr;
683 old_bss_size = OLD_SECTION_H(old_bss_index).sh_size
684 + OLD_SECTION_H(old_sbss_index).sh_size;
685 new_data2_index = old_sbss_index;
688 for (old_mdebug_index = 1; old_mdebug_index < (int) old_file_h->e_shnum;
692 fprintf (stderr, "Looking for .mdebug - found %s\n",
693 old_section_names + OLD_SECTION_H (old_mdebug_index).sh_name);
695 if (!strcmp (old_section_names + OLD_SECTION_H (old_mdebug_index).sh_name,
699 if (old_mdebug_index == old_file_h->e_shnum)
700 old_mdebug_index = 0;
702 for (old_data_index = 1; old_data_index < (int) old_file_h->e_shnum;
706 fprintf (stderr, "Looking for .data - found %s\n",
707 old_section_names + OLD_SECTION_H (old_data_index).sh_name);
709 if (!strcmp (old_section_names + OLD_SECTION_H (old_data_index).sh_name,
713 if (old_data_index == old_file_h->e_shnum)
716 #if defined (emacs) || !defined (DEBUG)
717 new_bss_addr = (ElfW(Addr)) sbrk (0);
719 new_bss_addr = old_bss_addr + old_bss_size + 0x1234;
721 new_data2_addr = old_bss_addr;
722 new_data2_size = new_bss_addr - old_bss_addr;
723 new_data2_offset = OLD_SECTION_H (old_data_index).sh_offset +
724 (new_data2_addr - OLD_SECTION_H (old_data_index).sh_addr);
727 fprintf (stderr, "old_bss_index %d\n", old_bss_index);
728 fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
729 fprintf (stderr, "old_bss_size %x\n", old_bss_size);
730 fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
731 fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
732 fprintf (stderr, "new_data2_size %x\n", new_data2_size);
733 fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
736 if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
737 fatal (".bss shrank when undumping???\n", 0, 0);
739 /* Set the output file to the right size and mmap it. Set
740 * pointers to various interesting objects. stat_buf still has
744 new_file = open (new_name, O_RDWR | O_CREAT, 0666);
746 fatal ("Can't creat (%s): errno %d\n", new_name, errno);
748 new_file_size = stat_buf.st_size + old_file_h->e_shentsize + new_data2_size;
750 if (ftruncate (new_file, new_file_size))
751 fatal ("Can't ftruncate (%s): errno %d\n", new_name, errno);
753 new_base = (caddr_t) mmap (0, new_file_size, PROT_READ | PROT_WRITE,
754 #ifdef UNEXEC_USE_MAP_PRIVATE
761 if (new_base == (caddr_t) -1)
762 fatal ("Can't mmap (%s): errno %d\n", new_name, errno);
764 new_file_h = (ElfW(Ehdr) *) new_base;
765 new_program_h = (ElfW(Phdr) *) ((byte *) new_base + old_file_h->e_phoff);
766 new_section_h = (ElfW(Shdr) *)
767 ((byte *) new_base + old_file_h->e_shoff + new_data2_size);
769 /* Make our new file, program and section headers as copies of the
773 memcpy (new_file_h, old_file_h, old_file_h->e_ehsize);
774 memcpy (new_program_h, old_program_h,
775 old_file_h->e_phnum * old_file_h->e_phentsize);
777 /* Modify the e_shstrndx if necessary. */
778 PATCH_INDEX (new_file_h->e_shstrndx);
780 /* Fix up file header. We'll add one section. Section header is
784 new_file_h->e_shoff += new_data2_size;
785 new_file_h->e_shnum += 1;
788 fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff);
789 fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum);
790 fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff);
791 fprintf (stderr, "New section count %d\n", new_file_h->e_shnum);
794 /* Fix up a new program header. Extend the writable data segment so
795 * that the bss area is covered too. Find that segment by looking
796 * for a segment that ends just before the .bss area. Make sure
797 * that no segments are above the new .data2. Put a loop at the end
798 * to adjust the offset and address of any segment that is above
799 * data2, just in case we decide to allow this later.
802 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
804 /* Compute maximum of all requirements for alignment of section. */
805 ElfW(Word) alignment = (NEW_PROGRAM_H (n)).p_align;
806 if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment)
807 alignment = OLD_SECTION_H (old_bss_index).sh_addralign;
810 /* According to r02kar@x4u2.desy.de (Karsten Kuenne)
811 and oliva@gnu.org (Alexandre Oliva), on IRIX 5.2, we
812 always get "Program segment above .bss" when dumping
813 when the executable doesn't have an sbss section. */
814 if (old_sbss_index != -1)
816 if (NEW_PROGRAM_H (n).p_vaddr + NEW_PROGRAM_H (n).p_filesz
817 > (old_sbss_index == -1
819 : round_up (old_bss_addr, alignment)))
820 fatal ("Program segment above .bss in %s\n", old_name, 0);
822 if (NEW_PROGRAM_H (n).p_type == PT_LOAD
823 && (round_up ((NEW_PROGRAM_H (n)).p_vaddr
824 + (NEW_PROGRAM_H (n)).p_filesz,
826 == round_up (old_bss_addr, alignment)))
830 fatal ("Couldn't find segment next to .bss in %s\n", old_name, 0);
832 /* Make sure that the size includes any padding before the old .bss
834 NEW_PROGRAM_H (n).p_filesz = new_bss_addr - NEW_PROGRAM_H (n).p_vaddr;
835 NEW_PROGRAM_H (n).p_memsz = NEW_PROGRAM_H (n).p_filesz;
837 #if 0 /* Maybe allow section after data2 - does this ever happen? */
838 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
840 if (NEW_PROGRAM_H (n).p_vaddr
841 && NEW_PROGRAM_H (n).p_vaddr >= new_data2_addr)
842 NEW_PROGRAM_H (n).p_vaddr += new_data2_size - old_bss_size;
844 if (NEW_PROGRAM_H (n).p_offset >= new_data2_offset)
845 NEW_PROGRAM_H (n).p_offset += new_data2_size;
849 /* Fix up section headers based on new .data2 section. Any section
850 * whose offset or virtual address is after the new .data2 section
851 * gets its value adjusted. .bss size becomes zero and new address
852 * is set. data2 section header gets added by copying the existing
853 * .data header and modifying the offset, address and size.
855 for (old_data_index = 1; old_data_index < (int) old_file_h->e_shnum;
857 if (!strcmp (old_section_names + OLD_SECTION_H (old_data_index).sh_name,
860 if (old_data_index == old_file_h->e_shnum)
861 fatal ("Can't find .data in %s.\n", old_name, 0);
863 /* Walk through all section headers, insert the new data2 section right
864 before the new bss section. */
865 for (n = 1, nn = 1; n < (int) old_file_h->e_shnum; n++, nn++)
868 /* If it is (s)bss section, insert the new data2 section before it. */
869 /* new_data2_index is the index of either old_sbss or old_bss, that was
870 chosen as a section for new_data2. */
871 if (n == new_data2_index)
873 /* Steal the data section header for this data2 section. */
874 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (old_data_index),
875 new_file_h->e_shentsize);
877 NEW_SECTION_H (nn).sh_addr = new_data2_addr;
878 NEW_SECTION_H (nn).sh_offset = new_data2_offset;
879 NEW_SECTION_H (nn).sh_size = new_data2_size;
880 /* Use the bss section's alignment. This will assure that the
881 new data2 section always be placed in the same spot as the old
882 bss section by any other application. */
883 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (n).sh_addralign;
885 /* Now copy over what we have in the memory now. */
886 memcpy (NEW_SECTION_H (nn).sh_offset + new_base,
887 (caddr_t) OLD_SECTION_H (n).sh_addr,
892 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n),
893 old_file_h->e_shentsize);
895 if (n == old_bss_index
896 /* The new bss and sbss section's size is zero, and its file offset
897 and virtual address should be off by NEW_DATA2_SIZE. */
898 || n == old_sbss_index
901 /* NN should be `old_s?bss_index + 1' at this point. */
902 NEW_SECTION_H (nn).sh_offset =
903 NEW_SECTION_H (new_data2_index).sh_offset + new_data2_size;
904 NEW_SECTION_H (nn).sh_addr =
905 NEW_SECTION_H (new_data2_index).sh_addr + new_data2_size;
906 /* Let the new bss section address alignment be the same as the
907 section address alignment followed the old bss section, so
908 this section will be placed in exactly the same place. */
909 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (nn).sh_addralign;
910 NEW_SECTION_H (nn).sh_size = 0;
914 /* Any section that was original placed AFTER the bss
915 section should now be off by NEW_DATA2_SIZE. */
916 #ifdef SOLARIS_POWERPC
917 /* On PPC Reference Platform running Solaris 2.5.1
918 the plt section is also of type NOBI like the bss section.
919 (not really stored) and therefore sections after the bss
920 section start at the plt offset. The plt section is always
921 the one just before the bss section.
922 It would be better to put the new data section before
923 the .plt section, or use libelf instead.
924 Erik Deumens, deumens@qtp.ufl.edu. */
925 if (NEW_SECTION_H (nn).sh_offset
926 >= OLD_SECTION_H (old_bss_index-1).sh_offset)
927 NEW_SECTION_H (nn).sh_offset += new_data2_size;
929 if (round_up (NEW_SECTION_H (nn).sh_offset,
930 OLD_SECTION_H (old_bss_index).sh_addralign)
932 NEW_SECTION_H (nn).sh_offset += new_data2_size;
934 /* Any section that was originally placed after the section
935 header table should now be off by the size of one section
936 header table entry. */
937 if (NEW_SECTION_H (nn).sh_offset > new_file_h->e_shoff)
938 NEW_SECTION_H (nn).sh_offset += new_file_h->e_shentsize;
941 /* If any section hdr refers to the section after the new .data
942 section, make it refer to next one because we have inserted
943 a new section in between. */
945 PATCH_INDEX (NEW_SECTION_H (nn).sh_link);
946 /* For symbol tables, info is a symbol table index,
947 so don't change it. */
948 if (NEW_SECTION_H (nn).sh_type != SHT_SYMTAB
949 && NEW_SECTION_H (nn).sh_type != SHT_DYNSYM)
950 PATCH_INDEX (NEW_SECTION_H (nn).sh_info);
952 /* Now, start to copy the content of sections. */
953 if (NEW_SECTION_H (nn).sh_type == SHT_NULL
954 || NEW_SECTION_H (nn).sh_type == SHT_NOBITS)
957 /* Write out the sections. .data and .data1 (and data2, called
958 ".data" in the strings table) get copied from the current process
959 instead of the old file. */
960 if (!strcmp (old_section_names + NEW_SECTION_H (n).sh_name, ".data")
961 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
963 /* Taking these sections from the current process, breaks
964 Linux in a subtle way. Binaries only run on the
965 architecture (e.g. i586 vs i686) of the dumping machine */
967 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
969 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
971 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
974 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
976 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
978 src = (caddr_t) OLD_SECTION_H (n).sh_addr;
980 src = old_base + OLD_SECTION_H (n).sh_offset;
982 memcpy (NEW_SECTION_H (nn).sh_offset + new_base, src,
983 NEW_SECTION_H (nn).sh_size);
986 /* Update Alpha COFF symbol table: */
987 if (strcmp (old_section_names + OLD_SECTION_H (n).sh_name, ".mdebug")
990 pHDRR symhdr = (pHDRR) (NEW_SECTION_H (nn).sh_offset + new_base);
992 symhdr->cbLineOffset += new_data2_size;
993 symhdr->cbDnOffset += new_data2_size;
994 symhdr->cbPdOffset += new_data2_size;
995 symhdr->cbSymOffset += new_data2_size;
996 symhdr->cbOptOffset += new_data2_size;
997 symhdr->cbAuxOffset += new_data2_size;
998 symhdr->cbSsOffset += new_data2_size;
999 symhdr->cbSsExtOffset += new_data2_size;
1000 symhdr->cbFdOffset += new_data2_size;
1001 symhdr->cbRfdOffset += new_data2_size;
1002 symhdr->cbExtOffset += new_data2_size;
1004 #endif /* __alpha__ */
1006 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
1007 if (NEW_SECTION_H (nn).sh_type == SHT_MIPS_DEBUG && old_mdebug_index)
1009 int diff = NEW_SECTION_H(nn).sh_offset
1010 - OLD_SECTION_H(old_mdebug_index).sh_offset;
1011 HDRR *phdr = (HDRR *)(NEW_SECTION_H (nn).sh_offset + new_base);
1015 phdr->cbLineOffset += diff;
1016 phdr->cbDnOffset += diff;
1017 phdr->cbPdOffset += diff;
1018 phdr->cbSymOffset += diff;
1019 phdr->cbOptOffset += diff;
1020 phdr->cbAuxOffset += diff;
1021 phdr->cbSsOffset += diff;
1022 phdr->cbSsExtOffset += diff;
1023 phdr->cbFdOffset += diff;
1024 phdr->cbRfdOffset += diff;
1025 phdr->cbExtOffset += diff;
1028 #endif /* __sony_news && _SYSTYPE_SYSV */
1031 /* Adjust the HDRR offsets in .mdebug and copy the
1032 line data if it's in its usual 'hole' in the object.
1033 Makes the new file debuggable with dbx.
1034 patches up two problems: the absolute file offsets
1035 in the HDRR record of .mdebug (see /usr/include/syms.h), and
1036 the ld bug that gets the line table in a hole in the
1037 elf file rather than in the .mdebug section proper.
1038 David Anderson. davea@sgi.com Jan 16,1994. */
1039 if (n == old_mdebug_index)
1041 #define MDEBUGADJUST(__ct,__fileaddr) \
1042 if (n_phdrr->__ct > 0) \
1044 n_phdrr->__fileaddr += movement; \
1047 HDRR * o_phdrr = (HDRR *)((byte *)old_base + OLD_SECTION_H (n).sh_offset);
1048 HDRR * n_phdrr = (HDRR *)((byte *)new_base + NEW_SECTION_H (nn).sh_offset);
1049 unsigned movement = new_data2_size;
1051 MDEBUGADJUST (idnMax, cbDnOffset);
1052 MDEBUGADJUST (ipdMax, cbPdOffset);
1053 MDEBUGADJUST (isymMax, cbSymOffset);
1054 MDEBUGADJUST (ioptMax, cbOptOffset);
1055 MDEBUGADJUST (iauxMax, cbAuxOffset);
1056 MDEBUGADJUST (issMax, cbSsOffset);
1057 MDEBUGADJUST (issExtMax, cbSsExtOffset);
1058 MDEBUGADJUST (ifdMax, cbFdOffset);
1059 MDEBUGADJUST (crfd, cbRfdOffset);
1060 MDEBUGADJUST (iextMax, cbExtOffset);
1061 /* The Line Section, being possible off in a hole of the object,
1062 requires special handling. */
1063 if (n_phdrr->cbLine > 0)
1065 if (o_phdrr->cbLineOffset > (OLD_SECTION_H (n).sh_offset
1066 + OLD_SECTION_H (n).sh_size))
1068 /* line data is in a hole in elf. do special copy and adjust
1069 for this ld mistake.
1071 n_phdrr->cbLineOffset += movement;
1073 memcpy (n_phdrr->cbLineOffset + new_base,
1074 o_phdrr->cbLineOffset + old_base, n_phdrr->cbLine);
1078 /* somehow line data is in .mdebug as it is supposed to be. */
1079 MDEBUGADJUST (cbLine, cbLineOffset);
1085 /* If it is the symbol table, its st_shndx field needs to be patched. */
1086 if (NEW_SECTION_H (nn).sh_type == SHT_SYMTAB
1087 || NEW_SECTION_H (nn).sh_type == SHT_DYNSYM)
1089 ElfW(Shdr) *spt = &NEW_SECTION_H (nn);
1090 unsigned int num = spt->sh_size / spt->sh_entsize;
1091 ElfW(Sym) * sym = (ElfW(Sym) *) (NEW_SECTION_H (nn).sh_offset +
1093 for (; num--; sym++)
1095 if ((sym->st_shndx == SHN_UNDEF)
1096 || (sym->st_shndx == SHN_ABS)
1097 || (sym->st_shndx == SHN_COMMON))
1100 PATCH_INDEX (sym->st_shndx);
1105 /* Update the symbol values of _edata and _end. */
1106 for (n = new_file_h->e_shnum - 1; n; n--)
1109 ElfW(Sym) *symp, *symendp;
1111 if (NEW_SECTION_H (n).sh_type != SHT_DYNSYM
1112 && NEW_SECTION_H (n).sh_type != SHT_SYMTAB)
1115 symnames = ((byte *) new_base
1116 + NEW_SECTION_H (NEW_SECTION_H (n).sh_link).sh_offset);
1117 symp = (ElfW(Sym) *) (NEW_SECTION_H (n).sh_offset + new_base);
1118 symendp = (ElfW(Sym) *) ((byte *)symp + NEW_SECTION_H (n).sh_size);
1120 for (; symp < symendp; symp ++)
1121 if (strcmp ((char *) (symnames + symp->st_name), "_end") == 0
1122 || strcmp ((char *) (symnames + symp->st_name), "end") == 0
1123 || strcmp ((char *) (symnames + symp->st_name), "_edata") == 0
1124 || strcmp ((char *) (symnames + symp->st_name), "edata") == 0)
1125 memcpy (&symp->st_value, &new_bss_addr, sizeof (new_bss_addr));
1128 /* This loop seeks out relocation sections for the data section, so
1129 that it can undo relocations performed by the runtime linker. */
1130 for (n = new_file_h->e_shnum - 1; n; n--)
1132 ElfW(Shdr) section = NEW_SECTION_H (n);
1133 switch (section.sh_type) {
1138 /* This code handles two different size structs, but there should
1139 be no harm in that provided that r_offset is always the first
1141 nn = section.sh_info;
1142 if (!strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".data")
1143 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1146 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1148 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1150 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1153 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1155 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1158 ElfW(Addr) offset = NEW_SECTION_H (nn).sh_addr -
1159 NEW_SECTION_H (nn).sh_offset;
1160 caddr_t reloc = old_base + section.sh_offset, end;
1161 for (end = reloc + section.sh_size; reloc < end;
1162 reloc += section.sh_entsize)
1164 ElfW(Addr) addr = ((ElfW(Rel) *) reloc)->r_offset - offset;
1166 /* The Alpha ELF binutils currently have a bug that
1167 sometimes results in relocs that contain all
1168 zeroes. Work around this for now... */
1169 if (((ElfW(Rel) *) reloc)->r_offset == 0)
1172 memcpy (new_base + addr, old_base + addr, sizeof(ElfW(Addr)));
1179 #ifdef UNEXEC_USE_MAP_PRIVATE
1180 if (lseek (new_file, 0, SEEK_SET) == -1)
1181 fatal ("Can't rewind (%s): errno %d\n", new_name, errno);
1183 if (write (new_file, new_base, new_file_size) != new_file_size)
1184 fatal ("Can't write (%s): errno %d\n", new_name, errno);
1187 /* Close the files and make the new file executable. */
1189 if (close (old_file))
1190 fatal ("Can't close (%s): errno %d\n", old_name, errno);
1192 if (close (new_file))
1193 fatal ("Can't close (%s): errno %d\n", new_name, errno);
1195 if (stat (new_name, &stat_buf) == -1)
1196 fatal ("Can't stat (%s): errno %d\n", new_name, errno);
1200 stat_buf.st_mode |= 0111 & ~n;
1201 if (chmod (new_name, stat_buf.st_mode) == -1)
1202 fatal ("Can't chmod (%s): errno %d\n", new_name, errno);