1 /* Unexec for Siemens machines running Sinix (modified SVR4).
2 Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992, 1993, 1994, 1995
3 Free Software Foundation, Inc.
5 This file is part of GNU Emacs.
7 GNU Emacs is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU Emacs is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU Emacs; see the file COPYING. If not, write to
19 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA.
22 In other words, you are welcome to use, share and improve this program.
23 You are forbidden to forbid anyone else to use, share and improve
24 what you give them. Help stamp out software-hoarding! */
26 /* Synched up with: FSF 19.31. */
29 * unexec.c - Convert a running program into an a.out file.
31 * Author: Spencer W. Thomas
32 * Computer Science Dept.
34 * Date: Tue Mar 2 1982
35 * Modified heavily since then.
38 * unexec (new_name, a_name, data_start, bss_start, entry_address)
39 * char *new_name, *a_name;
40 * unsigned data_start, bss_start, entry_address;
42 * Takes a snapshot of the program and makes an a.out format file in the
43 * file named by the string argument new_name.
44 * If a_name is non-NULL, the symbol table will be taken from the given file.
45 * On some machines, an existing a_name file is required.
47 * The boundaries within the a.out file may be adjusted with the data_start
48 * and bss_start arguments. Either or both may be given as 0 for defaults.
50 * Data_start gives the boundary between the text segment and the data
51 * segment of the program. The text segment can contain shared, read-only
52 * program code and literal data, while the data segment is always unshared
53 * and unprotected. Data_start gives the lowest unprotected address.
54 * The value you specify may be rounded down to a suitable boundary
55 * as required by the machine you are using.
57 * Specifying zero for data_start means the boundary between text and data
58 * should not be the same as when the program was loaded.
59 * If NO_REMAP is defined, the argument data_start is ignored and the
60 * segment boundaries are never changed.
62 * Bss_start indicates how much of the data segment is to be saved in the
63 * a.out file and restored when the program is executed. It gives the lowest
64 * unsaved address, and is rounded up to a page boundary. The default when 0
65 * is given assumes that the entire data segment is to be stored, including
66 * the previous data and bss as well as any additional storage allocated with
69 * The new file is set up to start at entry_address.
71 * If you make improvements I'd like to get them too.
72 * harpo!utah-cs!thomas, thomas@Utah-20
76 /* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
79 * Basic theory: the data space of the running process needs to be
80 * dumped to the output file. Normally we would just enlarge the size
81 * of .data, scooting everything down. But we can't do that in ELF,
82 * because there is often something between the .data space and the
85 * In the temacs dump below, notice that the Global Offset Table
86 * (.got) and the Dynamic link data (.dynamic) come between .data1 and
87 * .bss. It does not work to overlap .data with these fields.
89 * The solution is to create a new .data segment. This segment is
90 * filled with data from the current process. Since the contents of
91 * various sections refer to sections by index, the new .data segment
92 * is made the last in the table to avoid changing any existing index.
95 /* Modified by wtien@urbana.mcd.mot.com of Motorola Inc.
97 * The above mechanism does not work if the unexeced ELF file is being
98 * re-layout by other applications (such as `strip'). All the applications
99 * that re-layout the internal of ELF will layout all sections in ascending
100 * order of their file offsets. After the re-layout, the data2 section will
101 * still be the LAST section in the section header vector, but its file offset
102 * is now being pushed far away down, and causes part of it not to be mapped
103 * in (ie. not covered by the load segment entry in PHDR vector), therefore
104 * causes the new binary to fail.
106 * The solution is to modify the unexec algorithm to insert the new data2
107 * section header right before the new bss section header, so their file
108 * offsets will be in the ascending order. Since some of the section's (all
109 * sections AFTER the bss section) indexes are now changed, we also need to
110 * modify some fields to make them point to the right sections. This is done
111 * by macro PATCH_INDEX. All the fields that need to be patched are:
113 * 1. ELF header e_shstrndx field.
114 * 2. section header sh_link and sh_info field.
115 * 3. symbol table entry st_shndx field.
119 * New modifications for Siemens Nixdorf's MIPS-based machines.
120 * Marco.Walther@mch.sni.de
122 * The problem: Before the bss segment we have a so called sbss segment
123 * (small bss) and maybe an sdata segment. These segments
124 * must also be handled correct.
126 * /home1/marco/emacs/emacs-19.22/src
131 * **** SECTION HEADER TABLE ****
132 * [No] Type Flags Addr Offset Size Name
133 * Link Info Adralgn Entsize
135 * [1] PBIT -A-- 0x4000f4 0xf4 0x13 .interp
138 * [2] REGI -A-- 0x400108 0x108 0x18 .reginfo
141 * [3] DYNM -A-- 0x400120 0x120 0xb8 .dynamic
144 * [4] HASH -A-- 0x4001d8 0x1d8 0x8a0 .hash
147 * [5] DYNS -A-- 0x400a78 0xa78 0x11f0 .dynsym
150 * [6] STRT -A-- 0x401c68 0x1c68 0xbf9 .dynstr
153 * [7] REL -A-- 0x402864 0x2864 0x18 .rel.dyn
156 * [8] PBIT -AI- 0x402880 0x2880 0x60 .init
159 * [9] PBIT -AI- 0x4028e0 0x28e0 0x1234 .plt
162 * [10] PBIT -AI- 0x403b20 0x3b20 0xee400 .text
165 * [11] PBIT -AI- 0x4f1f20 0xf1f20 0x60 .fini
168 * [12] PBIT -A-- 0x4f1f80 0xf1f80 0xd90 .rdata
171 * [13] PBIT -A-- 0x4f2d10 0xf2d10 0x17e0 .rodata
174 * [14] PBIT WA-- 0x5344f0 0xf44f0 0x4b3e4 .data <<<<<
177 * [15] PBIT WA-G 0x57f8d4 0x13f8d4 0x2a84 .got
180 * [16] PBIT WA-G 0x582360 0x142360 0x10 .sdata <<<<<
183 * [17] NOBI WA-G 0x582370 0x142370 0xb84 .sbss <<<<<
186 * [18] NOBI WA-- 0x582f00 0x142370 0x27ec0 .bss <<<<<
189 * [19] SYMT ---- 0 0x142370 0x10e40 .symtab
192 * [20] STRT ---- 0 0x1531b0 0xed9e .strtab
195 * [21] STRT ---- 0 0x161f4e 0xb5 .shstrtab
198 * [22] PBIT ---- 0 0x162003 0x28e2a .comment
201 * [23] PBIT ---- 0 0x18ae2d 0x592 .debug
204 * [24] PBIT ---- 0 0x18b3bf 0x80 .line
207 * [25] MDBG ---- 0 0x18b440 0x60 .mdebug
215 * **** SECTION HEADER TABLE ****
216 * [No] Type Flags Addr Offset Size Name
217 * Link Info Adralgn Entsize
219 * [1] PBIT -A-- 0x4000f4 0xf4 0x13 .interp
222 * [2] REGI -A-- 0x400108 0x108 0x18 .reginfo
225 * [3] DYNM -A-- 0x400120 0x120 0xb8 .dynamic
228 * [4] HASH -A-- 0x4001d8 0x1d8 0x8a0 .hash
231 * [5] DYNS -A-- 0x400a78 0xa78 0x11f0 .dynsym
234 * [6] STRT -A-- 0x401c68 0x1c68 0xbf9 .dynstr
237 * [7] REL -A-- 0x402864 0x2864 0x18 .rel.dyn
240 * [8] PBIT -AI- 0x402880 0x2880 0x60 .init
243 * [9] PBIT -AI- 0x4028e0 0x28e0 0x1234 .plt
246 * [10] PBIT -AI- 0x403b20 0x3b20 0xee400 .text
249 * [11] PBIT -AI- 0x4f1f20 0xf1f20 0x60 .fini
252 * [12] PBIT -A-- 0x4f1f80 0xf1f80 0xd90 .rdata
255 * [13] PBIT -A-- 0x4f2d10 0xf2d10 0x17e0 .rodata
258 * [14] PBIT WA-- 0x5344f0 0xf44f0 0x4b3e4 .data <<<<<
261 * [15] PBIT WA-G 0x57f8d4 0x13f8d4 0x2a84 .got
264 * [16] PBIT WA-G 0x582360 0x142360 0xb94 .sdata <<<<<
267 * [17] PBIT WA-- 0x582f00 0x142f00 0x94100 .data <<<<<
270 * [18] NOBI WA-G 0x617000 0x1d7000 0 .sbss <<<<<
273 * [19] NOBI WA-- 0x617000 0x1d7000 0 .bss <<<<<
276 * [20] SYMT ---- 0 0x1d7000 0x10e40 .symtab
279 * [21] STRT ---- 0 0x1e7e40 0xed9e .strtab
282 * [22] STRT ---- 0 0x1f6bde 0xb5 .shstrtab
285 * [23] PBIT ---- 0 0x1f6c93 0x28e2a .comment
288 * [24] PBIT ---- 0 0x21fabd 0x592 .debug
291 * [25] PBIT ---- 0 0x22004f 0x80 .line
294 * [26] MDBG ---- 0 0x2200d0 0x60 .mdebug
299 #include <sys/types.h>
301 #include <sys/stat.h>
308 #include <sys/mman.h>
311 #define fatal(a, b, c) fprintf(stderr, a, b, c), exit(1)
313 extern void fatal(char *, ...);
316 /* Get the address of a particular section or program header entry,
317 * accounting for the size of the entries.
320 #define OLD_SECTION_H(n) \
321 (*(Elf32_Shdr *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
322 #define NEW_SECTION_H(n) \
323 (*(Elf32_Shdr *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
324 #define OLD_PROGRAM_H(n) \
325 (*(Elf32_Phdr *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
326 #define NEW_PROGRAM_H(n) \
327 (*(Elf32_Phdr *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
329 #define PATCH_INDEX(n) \
331 if ((n) >= old_sbss_index) \
332 (n) += 1 + (old_sdata_index ? 0 : 1); } while (0)
334 typedef unsigned char byte;
336 /* Round X up to a multiple of Y. */
348 /* ****************************************************************
353 * In ELF, this works by replacing the old .bss section with a new
354 * .data section, and inserting an empty .bss immediately afterwards.
358 unexec (new_name, old_name, data_start, bss_start, entry_address)
359 char *new_name, *old_name;
360 unsigned data_start, bss_start, entry_address;
362 extern unsigned int bss_end;
363 int new_file, old_file, new_file_size;
365 /* Pointers to the base of the image of the two files. */
366 caddr_t old_base, new_base;
368 /* Pointers to the file, program and section headers for the old and new
371 Elf32_Ehdr *old_file_h, *new_file_h;
372 Elf32_Phdr *old_program_h, *new_program_h;
373 Elf32_Shdr *old_section_h, *new_section_h;
375 /* Point to the section name table in the old file */
376 char *old_section_names;
378 Elf32_Addr old_bss_addr, new_bss_addr;
379 Elf32_Addr old_sbss_addr;
380 Elf32_Word old_bss_size, new_data2_size;
381 Elf32_Word old_sbss_size, new_data3_size;
382 Elf32_Off new_data2_offset;
383 Elf32_Off new_data3_offset;
384 Elf32_Addr new_data2_addr;
385 Elf32_Addr new_data3_addr;
387 Elf32_Word old_sdata_size, new_sdata_size;
388 int old_sdata_index = 0;
390 int n, nn, old_data_index, new_data2_align;
394 struct stat stat_buf;
396 /* Open the old file & map it into the address space. */
398 old_file = open (old_name, O_RDONLY);
401 fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
403 if (fstat (old_file, &stat_buf) == -1)
404 fatal ("Can't fstat(%s): errno %d\n", old_name, errno);
406 old_base = mmap (0, stat_buf.st_size, PROT_READ, MAP_SHARED, old_file, 0);
408 if (old_base == (caddr_t) -1)
409 fatal ("Can't mmap(%s): errno %d\n", old_name, errno);
412 fprintf (stderr, "mmap(%s, %x) -> %x\n", old_name, stat_buf.st_size,
416 /* Get pointers to headers & section names */
418 old_file_h = (Elf32_Ehdr *) old_base;
419 old_program_h = (Elf32_Phdr *) ((byte *) old_base + old_file_h->e_phoff);
420 old_section_h = (Elf32_Shdr *) ((byte *) old_base + old_file_h->e_shoff);
421 old_section_names = (char *) old_base
422 + OLD_SECTION_H(old_file_h->e_shstrndx).sh_offset;
424 /* Find the old .sbss section.
427 for (old_sbss_index = 1; old_sbss_index < old_file_h->e_shnum;
431 fprintf (stderr, "Looking for .sbss - found %s\n",
432 old_section_names + OLD_SECTION_H(old_sbss_index).sh_name);
434 if (!strcmp (old_section_names + OLD_SECTION_H(old_sbss_index).sh_name,
438 if (old_sbss_index == old_file_h->e_shnum)
439 fatal ("Can't find .sbss in %s.\n", old_name, 0);
441 if (!strcmp(old_section_names + OLD_SECTION_H(old_sbss_index - 1).sh_name,
444 old_sdata_index = old_sbss_index - 1;
448 /* Find the old .bss section.
451 for (old_bss_index = 1; old_bss_index < old_file_h->e_shnum; old_bss_index++)
454 fprintf (stderr, "Looking for .bss - found %s\n",
455 old_section_names + OLD_SECTION_H(old_bss_index).sh_name);
457 if (!strcmp (old_section_names + OLD_SECTION_H(old_bss_index).sh_name,
461 if (old_bss_index == old_file_h->e_shnum)
462 fatal ("Can't find .bss in %s.\n", old_name, 0);
464 if (old_sbss_index != (old_bss_index - 1))
465 fatal (".sbss should come immediately before .bss in %s.\n", old_name, 0);
467 /* Figure out parameters of the new data3 and data2 sections.
468 * Change the sbss and bss sections.
471 old_bss_addr = OLD_SECTION_H(old_bss_index).sh_addr;
472 old_bss_size = OLD_SECTION_H(old_bss_index).sh_size;
474 old_sbss_addr = OLD_SECTION_H(old_sbss_index).sh_addr;
475 old_sbss_size = OLD_SECTION_H(old_sbss_index).sh_size;
479 old_sdata_size = OLD_SECTION_H(old_sdata_index).sh_size;
482 #if defined(emacs) || !defined(DEBUG)
483 bss_end = (unsigned int) sbrk (0);
484 new_bss_addr = (Elf32_Addr) bss_end;
486 new_bss_addr = old_bss_addr + old_bss_size + 0x1234;
490 new_sdata_size = OLD_SECTION_H(old_sbss_index).sh_offset -
491 OLD_SECTION_H(old_sdata_index).sh_offset + old_sbss_size;
494 new_data3_addr = old_sbss_addr;
495 new_data3_size = old_sbss_size;
496 new_data3_offset = OLD_SECTION_H(old_sbss_index).sh_offset;
498 new_data2_addr = old_bss_addr;
499 new_data2_size = new_bss_addr - old_bss_addr;
500 new_data2_align = (new_data3_offset + old_sbss_size) %
501 OLD_SECTION_H(old_bss_index).sh_addralign;
502 new_data2_align = new_data2_align ?
503 OLD_SECTION_H(old_bss_index).sh_addralign - new_data2_align :
505 new_data2_offset = new_data3_offset + old_sbss_size + new_data2_align;
507 old_bss_padding = OLD_SECTION_H(old_bss_index).sh_offset -
508 OLD_SECTION_H(old_sbss_index).sh_offset;
510 fprintf (stderr, "old_bss_index %d\n", old_bss_index);
511 fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
512 fprintf (stderr, "old_bss_size %x\n", old_bss_size);
513 fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
514 fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
515 fprintf (stderr, "new_data2_size %x\n", new_data2_size);
516 fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
517 fprintf (stderr, "old_sbss_index %d\n", old_sbss_index);
518 fprintf (stderr, "old_sbss_addr %x\n", old_sbss_addr);
519 fprintf (stderr, "old_sbss_size %x\n", old_sbss_size);
522 fprintf (stderr, "old_sdata_size %x\n", old_sdata_size);
523 fprintf (stderr, "new_sdata_size %x\n", new_sdata_size);
527 fprintf (stderr, "new_data3_addr %x\n", new_data3_addr);
528 fprintf (stderr, "new_data3_size %x\n", new_data3_size);
529 fprintf (stderr, "new_data3_offset %x\n", new_data3_offset);
533 if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
534 fatal (".bss shrank when undumping???\n", 0, 0);
536 /* Set the output file to the right size and mmap(2) it. Set
537 * pointers to various interesting objects. stat_buf still has
541 new_file = open (new_name, O_RDWR | O_CREAT, 0666);
543 fatal ("Can't creat(%s): errno %d\n", new_name, errno);
545 new_file_size = stat_buf.st_size +
546 ((1 + (old_sdata_index ? 0 : 1)) * old_file_h->e_shentsize) +
547 new_data2_size + new_data3_size + new_data2_align;
549 if (ftruncate (new_file, new_file_size))
550 fatal ("Can't ftruncate(%s): errno %d\n", new_name, errno);
552 new_base = mmap (0, new_file_size, PROT_READ | PROT_WRITE, MAP_SHARED,
555 if (new_base == (caddr_t) -1)
556 fatal ("Can't mmap(%s): errno %d\n", new_name, errno);
558 new_file_h = (Elf32_Ehdr *) new_base;
559 new_program_h = (Elf32_Phdr *) ((byte *) new_base + old_file_h->e_phoff);
560 new_section_h = (Elf32_Shdr *) ((byte *) new_base +
561 old_file_h->e_shoff +
566 /* Make our new file, program and section headers as copies of the
570 memcpy (new_file_h, old_file_h, old_file_h->e_ehsize);
571 memcpy (new_program_h, old_program_h,
572 old_file_h->e_phnum * old_file_h->e_phentsize);
574 /* Modify the e_shstrndx if necessary. */
575 PATCH_INDEX (new_file_h->e_shstrndx);
577 /* Fix up file header. We'll add one section. Section header is
581 new_file_h->e_shoff += new_data2_size + new_data2_align + new_data3_size;
582 new_file_h->e_shnum += 1 + (old_sdata_index ? 0 : 1);
585 fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff);
586 fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum);
587 fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff);
588 fprintf (stderr, "New section count %d\n", new_file_h->e_shnum);
591 /* Fix up a new program header. Extend the writable data segment so
592 * that the bss area is covered too. Find that segment by looking
593 * for a segment that ends just before the .bss area. Make sure
594 * that no segments are above the new .data2. Put a loop at the end
595 * to adjust the offset and address of any segment that is above
596 * data2, just in case we decide to allow this later.
599 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
601 /* Compute maximum of all requirements for alignment of section. */
602 int alignment = (NEW_PROGRAM_H (n)).p_align;
603 if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment)
604 alignment = OLD_SECTION_H (old_bss_index).sh_addralign;
606 if ((OLD_SECTION_H (old_sbss_index)).sh_addralign > alignment)
607 alignment = OLD_SECTION_H (old_sbss_index).sh_addralign;
609 /* Supposedly this condition is okay for the SGI. */
611 if (NEW_PROGRAM_H(n).p_vaddr + NEW_PROGRAM_H(n).p_filesz > old_bss_addr)
612 fatal ("Program segment above .bss in %s\n", old_name, 0);
615 if (NEW_PROGRAM_H(n).p_type == PT_LOAD
616 && (round_up ((NEW_PROGRAM_H (n)).p_vaddr
617 + (NEW_PROGRAM_H (n)).p_filesz,
619 == round_up (old_bss_addr, alignment)))
623 fatal ("Couldn't find segment next to .bss in %s\n", old_name, 0);
625 NEW_PROGRAM_H(n).p_filesz += new_data2_size + new_data2_align +
627 NEW_PROGRAM_H(n).p_memsz = NEW_PROGRAM_H(n).p_filesz;
629 #if 1 /* Maybe allow section after data2 - does this ever happen? */
630 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
632 if (NEW_PROGRAM_H(n).p_vaddr
633 && NEW_PROGRAM_H(n).p_vaddr >= new_data3_addr)
634 NEW_PROGRAM_H(n).p_vaddr += new_data2_size - old_bss_size +
635 new_data3_size - old_sbss_size;
637 if (NEW_PROGRAM_H(n).p_offset >= new_data3_offset)
638 NEW_PROGRAM_H(n).p_offset += new_data2_size + new_data2_align +
643 /* Fix up section headers based on new .data2 section. Any section
644 * whose offset or virtual address is after the new .data2 section
645 * gets its value adjusted. .bss size becomes zero and new address
646 * is set. data2 section header gets added by copying the existing
647 * .data header and modifying the offset, address and size.
649 for (old_data_index = 1; old_data_index < old_file_h->e_shnum;
651 if (!strcmp (old_section_names + OLD_SECTION_H(old_data_index).sh_name,
654 if (old_data_index == old_file_h->e_shnum)
655 fatal ("Can't find .data in %s.\n", old_name, 0);
657 /* Walk through all section headers, insert the new data2 section right
658 before the new bss section. */
659 for (n = 1, nn = 1; n < old_file_h->e_shnum; n++, nn++)
663 if (n == old_sbss_index)
665 /* If it is sbss section, insert the new data3 section before it. */
667 /* Steal the data section header for this data3 section. */
668 if (!old_sdata_index)
670 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(old_data_index),
671 new_file_h->e_shentsize);
673 NEW_SECTION_H(nn).sh_addr = new_data3_addr;
674 NEW_SECTION_H(nn).sh_offset = new_data3_offset;
675 NEW_SECTION_H(nn).sh_size = new_data3_size;
676 NEW_SECTION_H(nn).sh_flags = OLD_SECTION_H(n).sh_flags;
677 /* Use the sbss section's alignment. This will assure that the
678 new data3 section always be placed in the same spot as the old
679 sbss section by any other application. */
680 NEW_SECTION_H(nn).sh_addralign = OLD_SECTION_H(n).sh_addralign;
682 /* Now copy over what we have in the memory now. */
683 memcpy (NEW_SECTION_H(nn).sh_offset + new_base,
684 (caddr_t) OLD_SECTION_H(n).sh_addr,
686 /* the new .data2 section should also come before the
687 * new .sbss section */
692 /* We always have a .sdata section: append the contents of the
695 memcpy (new_data3_offset + new_base,
696 (caddr_t) OLD_SECTION_H(n).sh_addr,
701 else if (n == old_bss_index)
703 /* If it is bss section, insert the new data2 section before it. */
705 Elf32_Word tmp_align;
708 tmp_align = OLD_SECTION_H(n).sh_addralign;
709 tmp_addr = OLD_SECTION_H(n).sh_addr;
712 /* Steal the data section header for this data2 section. */
713 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(old_data_index),
714 new_file_h->e_shentsize);
716 NEW_SECTION_H(nn).sh_addr = new_data2_addr;
717 NEW_SECTION_H(nn).sh_offset = new_data2_offset;
718 NEW_SECTION_H(nn).sh_size = new_data2_size;
719 /* Use the bss section's alignment. This will assure that the
720 new data2 section always be placed in the same spot as the old
721 bss section by any other application. */
722 NEW_SECTION_H(nn).sh_addralign = tmp_align;
724 /* Now copy over what we have in the memory now. */
725 memcpy (NEW_SECTION_H(nn).sh_offset + new_base,
726 (caddr_t) tmp_addr, new_data2_size);
730 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(n),
731 old_file_h->e_shentsize);
733 if (old_sdata_index && n == old_sdata_index)
734 /* The old .sdata section has now a new size */
735 NEW_SECTION_H(nn).sh_size = new_sdata_size;
737 /* The new bss section's size is zero, and its file offset and virtual
738 address should be off by NEW_DATA2_SIZE. */
739 if (n == old_sbss_index)
741 /* NN should be `old_sbss_index + 2' at this point. */
742 NEW_SECTION_H(nn).sh_offset += new_data2_size + new_data2_align +
744 NEW_SECTION_H(nn).sh_addr += new_data2_size + new_data2_align +
746 /* Let the new bss section address alignment be the same as the
747 section address alignment followed the old bss section, so
748 this section will be placed in exactly the same place. */
749 NEW_SECTION_H(nn).sh_addralign =
750 OLD_SECTION_H(nn + (old_sdata_index ? 1 : 0)).sh_addralign;
751 NEW_SECTION_H(nn).sh_size = 0;
753 else if (n == old_bss_index)
755 /* NN should be `old_bss_index + 2' at this point. */
756 NEW_SECTION_H(nn).sh_offset += new_data2_size + new_data2_align +
757 new_data3_size - old_bss_padding;
758 NEW_SECTION_H(nn).sh_addr += new_data2_size;
759 /* Let the new bss section address alignment be the same as the
760 section address alignment followed the old bss section, so
761 this section will be placed in exactly the same place. */
762 NEW_SECTION_H(nn).sh_addralign =
763 OLD_SECTION_H((nn - (old_sdata_index ? 0 : 1))).sh_addralign;
764 NEW_SECTION_H(nn).sh_size = 0;
766 /* Any section that was original placed AFTER the bss section should now
767 be off by NEW_DATA2_SIZE. */
768 else if (NEW_SECTION_H(nn).sh_offset >= new_data3_offset)
769 NEW_SECTION_H(nn).sh_offset += new_data2_size +
774 /* If any section hdr refers to the section after the new .data
775 section, make it refer to next one because we have inserted
776 a new section in between. */
778 PATCH_INDEX(NEW_SECTION_H(nn).sh_link);
779 PATCH_INDEX(NEW_SECTION_H(nn).sh_info);
781 /* Now, start to copy the content of sections. */
782 if (NEW_SECTION_H(nn).sh_type == SHT_NULL
783 || NEW_SECTION_H(nn).sh_type == SHT_NOBITS)
786 /* Write out the sections. .data, .data1 and .sdata get copied from
787 * the current process instead of the old file.
789 if (!strcmp (old_section_names + OLD_SECTION_H(n).sh_name, ".data") ||
790 !strcmp (old_section_names + OLD_SECTION_H(n).sh_name, ".data1") ||
791 (old_sdata_index && (n == old_sdata_index)))
792 src = (caddr_t) OLD_SECTION_H(n).sh_addr;
794 src = old_base + OLD_SECTION_H(n).sh_offset;
796 memcpy (NEW_SECTION_H(nn).sh_offset + new_base, src,
797 ((n == old_sdata_index) ?
799 NEW_SECTION_H(nn).sh_size));
801 /* If it is the symbol table, its st_shndx field needs to be patched. */
802 if (NEW_SECTION_H(nn).sh_type == SHT_SYMTAB
803 || NEW_SECTION_H(nn).sh_type == SHT_DYNSYM)
805 Elf32_Shdr *spt = &NEW_SECTION_H(nn);
806 unsigned int num = spt->sh_size / spt->sh_entsize;
807 Elf32_Sym * sym = (Elf32_Sym *) (NEW_SECTION_H(nn).sh_offset +
811 if ((sym->st_shndx == SHN_UNDEF)
812 || (sym->st_shndx == SHN_ABS)
813 || (sym->st_shndx == SHN_COMMON))
816 PATCH_INDEX(sym->st_shndx);
821 /* Close the files and make the new file executable */
823 if (close (old_file))
824 fatal ("Can't close(%s): errno %d\n", old_name, errno);
826 if (close (new_file))
827 fatal ("Can't close(%s): errno %d\n", new_name, errno);
829 if (stat (new_name, &stat_buf) == -1)
830 fatal ("Can't stat(%s): errno %d\n", new_name, errno);
834 stat_buf.st_mode |= 0111 & ~n;
835 if (chmod (new_name, stat_buf.st_mode) == -1)
836 fatal ("Can't chmod(%s): errno %d\n", new_name, errno);