*** empty log message ***
[emacs.git] / src / unexsni.c
blob8d72acf1a18fafc1c13a0fcfe47ecba2d6e3686f
1 /* Unexec for Siemens machines running Sinix (modified SVR4).
2 Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992, 1993, 1994, 1995, 2002,
3 2003, 2004, 2005, 2006 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)
10 any later version.
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., 51 Franklin Street, Fifth Floor,
20 Boston, MA 02110-1301, 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! */
27 * unexec.c - Convert a running program into an a.out file.
29 * Author: Spencer W. Thomas
30 * Computer Science Dept.
31 * University of Utah
32 * Date: Tue Mar 2 1982
33 * Modified heavily since then.
35 * Synopsis:
36 * unexec (new_name, a_name, data_start, bss_start, entry_address)
37 * char *new_name, *a_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 a_name is non-NULL, the symbol table will be taken from the given file.
43 * On some machines, an existing a_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
65 * break (2).
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.
75 * ELF support added.
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
81 * .bss space.
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.
93 /* Modified by wtien@urbana.mcd.mot.com of Motorola Inc.
95 * The above mechanism does not work if the unexeced ELF file is being
96 * re-layout by other applications (such as `strip'). All the applications
97 * that re-layout the internal of ELF will layout all sections in ascending
98 * order of their file offsets. After the re-layout, the data2 section will
99 * still be the LAST section in the section header vector, but its file offset
100 * is now being pushed far away down, and causes part of it not to be mapped
101 * in (ie. not covered by the load segment entry in PHDR vector), therefore
102 * causes the new binary to fail.
104 * The solution is to modify the unexec algorithm to insert the new data2
105 * section header right before the new bss section header, so their file
106 * offsets will be in the ascending order. Since some of the section's (all
107 * sections AFTER the bss section) indexes are now changed, we also need to
108 * modify some fields to make them point to the right sections. This is done
109 * by macro PATCH_INDEX. All the fields that need to be patched are:
111 * 1. ELF header e_shstrndx field.
112 * 2. section header sh_link and sh_info field.
113 * 3. symbol table entry st_shndx field.
117 * New modifications for Siemens Nixdorf's MIPS-based machines.
118 * Marco.Walther@mch.sni.de
119 * marco@inreach.com
121 * The problem: Before the bss segment we have a so called sbss segment
122 * (small bss) and maybe an sdata segment. These segments
123 * must also be handled correct.
125 * /home1/marco/emacs/emacs-19.22/src
126 * dump -hv temacs
128 * temacs:
130 * **** SECTION HEADER TABLE ****
131 * [No] Type Flags Addr Offset Size Name
132 * Link Info Adralgn Entsize
134 * [1] PBIT -A-- 0x4000f4 0xf4 0x13 .interp
135 * 0 0 0x1 0
137 * [2] REGI -A-- 0x400108 0x108 0x18 .reginfo
138 * 0 0 0x4 0x18
140 * [3] DYNM -A-- 0x400120 0x120 0xb8 .dynamic
141 * 6 0 0x4 0x8
143 * [4] HASH -A-- 0x4001d8 0x1d8 0x8a0 .hash
144 * 5 0 0x4 0x4
146 * [5] DYNS -A-- 0x400a78 0xa78 0x11f0 .dynsym
147 * 6 2 0x4 0x10
149 * [6] STRT -A-- 0x401c68 0x1c68 0xbf9 .dynstr
150 * 0 0 0x1 0
152 * [7] REL -A-- 0x402864 0x2864 0x18 .rel.dyn
153 * 5 14 0x4 0x8
155 * [8] PBIT -AI- 0x402880 0x2880 0x60 .init
156 * 0 0 0x10 0x1
158 * [9] PBIT -AI- 0x4028e0 0x28e0 0x1234 .plt
159 * 0 0 0x4 0x4
161 * [10] PBIT -AI- 0x403b20 0x3b20 0xee400 .text
162 * 0 0 0x20 0x1
164 * [11] PBIT -AI- 0x4f1f20 0xf1f20 0x60 .fini
165 * 0 0 0x10 0x1
167 * [12] PBIT -A-- 0x4f1f80 0xf1f80 0xd90 .rdata
168 * 0 0 0x10 0x1
170 * [13] PBIT -A-- 0x4f2d10 0xf2d10 0x17e0 .rodata
171 * 0 0 0x10 0x1
173 * [14] PBIT WA-- 0x5344f0 0xf44f0 0x4b3e4 .data <<<<<
174 * 0 0 0x10 0x1
176 * [15] PBIT WA-G 0x57f8d4 0x13f8d4 0x2a84 .got
177 * 0 0 0x4 0x4
179 * [16] PBIT WA-G 0x582360 0x142360 0x10 .sdata <<<<<
180 * 0 0 0x10 0x1
182 * [17] NOBI WA-G 0x582370 0x142370 0xb84 .sbss <<<<<
183 * 0 0 0x4 0
185 * [18] NOBI WA-- 0x582f00 0x142370 0x27ec0 .bss <<<<<
186 * 0 0 0x10 0x1
188 * [19] SYMT ---- 0 0x142370 0x10e40 .symtab
189 * 20 1108 0x4 0x10
191 * [20] STRT ---- 0 0x1531b0 0xed9e .strtab
192 * 0 0 0x1 0
194 * [21] STRT ---- 0 0x161f4e 0xb5 .shstrtab
195 * 0 0 0x1 0
197 * [22] PBIT ---- 0 0x162003 0x28e2a .comment
198 * 0 0 0x1 0x1
200 * [23] PBIT ---- 0 0x18ae2d 0x592 .debug
201 * 0 0 0x1 0
203 * [24] PBIT ---- 0 0x18b3bf 0x80 .line
204 * 0 0 0x1 0
206 * [25] MDBG ---- 0 0x18b440 0x60 .mdebug
207 * 0 0 0x4 0
210 * dump -hv emacs
212 * emacs:
214 * **** SECTION HEADER TABLE ****
215 * [No] Type Flags Addr Offset Size Name
216 * Link Info Adralgn Entsize
218 * [1] PBIT -A-- 0x4000f4 0xf4 0x13 .interp
219 * 0 0 0x1 0
221 * [2] REGI -A-- 0x400108 0x108 0x18 .reginfo
222 * 0 0 0x4 0x18
224 * [3] DYNM -A-- 0x400120 0x120 0xb8 .dynamic
225 * 6 0 0x4 0x8
227 * [4] HASH -A-- 0x4001d8 0x1d8 0x8a0 .hash
228 * 5 0 0x4 0x4
230 * [5] DYNS -A-- 0x400a78 0xa78 0x11f0 .dynsym
231 * 6 2 0x4 0x10
233 * [6] STRT -A-- 0x401c68 0x1c68 0xbf9 .dynstr
234 * 0 0 0x1 0
236 * [7] REL -A-- 0x402864 0x2864 0x18 .rel.dyn
237 * 5 14 0x4 0x8
239 * [8] PBIT -AI- 0x402880 0x2880 0x60 .init
240 * 0 0 0x10 0x1
242 * [9] PBIT -AI- 0x4028e0 0x28e0 0x1234 .plt
243 * 0 0 0x4 0x4
245 * [10] PBIT -AI- 0x403b20 0x3b20 0xee400 .text
246 * 0 0 0x20 0x1
248 * [11] PBIT -AI- 0x4f1f20 0xf1f20 0x60 .fini
249 * 0 0 0x10 0x1
251 * [12] PBIT -A-- 0x4f1f80 0xf1f80 0xd90 .rdata
252 * 0 0 0x10 0x1
254 * [13] PBIT -A-- 0x4f2d10 0xf2d10 0x17e0 .rodata
255 * 0 0 0x10 0x1
257 * [14] PBIT WA-- 0x5344f0 0xf44f0 0x4b3e4 .data <<<<<
258 * 0 0 0x10 0x1
260 * [15] PBIT WA-G 0x57f8d4 0x13f8d4 0x2a84 .got
261 * 0 0 0x4 0x4
263 * [16] PBIT WA-G 0x582360 0x142360 0xb94 .sdata <<<<<
264 * 0 0 0x10 0x1
266 * [17] PBIT WA-- 0x582f00 0x142f00 0x94100 .data <<<<<
267 * 0 0 0x10 0x1
269 * [18] NOBI WA-G 0x617000 0x1d7000 0 .sbss <<<<<
270 * 0 0 0x4 0
272 * [19] NOBI WA-- 0x617000 0x1d7000 0 .bss <<<<<
273 * 0 0 0x4 0x1
275 * [20] SYMT ---- 0 0x1d7000 0x10e40 .symtab
276 * 21 1109 0x4 0x10
278 * [21] STRT ---- 0 0x1e7e40 0xed9e .strtab
279 * 0 0 0x1 0
281 * [22] STRT ---- 0 0x1f6bde 0xb5 .shstrtab
282 * 0 0 0x1 0
284 * [23] PBIT ---- 0 0x1f6c93 0x28e2a .comment
285 * 0 0 0x1 0x1
287 * [24] PBIT ---- 0 0x21fabd 0x592 .debug
288 * 0 0 0x1 0
290 * [25] PBIT ---- 0 0x22004f 0x80 .line
291 * 0 0 0x1 0
293 * [26] MDBG ---- 0 0x2200d0 0x60 .mdebug
294 * 0 0 0x4 0
298 #include <sys/types.h>
299 #include <stdio.h>
300 #include <sys/stat.h>
301 #include <memory.h>
302 #include <string.h>
303 #include <errno.h>
304 #include <unistd.h>
305 #include <fcntl.h>
306 #include <elf.h>
307 #include <sys/mman.h>
308 #include <assert.h>
310 /* #define DEBUG */
312 #ifndef emacs
313 #define fatal(a, b, c) fprintf(stderr, a, b, c), exit(1)
314 #else
315 extern void fatal(char *, ...);
316 #endif
318 /* Get the address of a particular section or program header entry,
319 * accounting for the size of the entries.
322 #define OLD_SECTION_H(n) \
323 (*(Elf32_Shdr *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
324 #define NEW_SECTION_H(n) \
325 (*(Elf32_Shdr *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
326 #define OLD_PROGRAM_H(n) \
327 (*(Elf32_Phdr *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
328 #define NEW_PROGRAM_H(n) \
329 (*(Elf32_Phdr *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
331 #define PATCH_INDEX(n) \
332 do { \
333 if ((n) >= old_sbss_index) \
334 (n) += 1 + (old_sdata_index ? 0 : 1); } while (0)
336 typedef unsigned char byte;
338 /* Round X up to a multiple of Y. */
341 round_up (x, y)
342 int x, y;
344 int rem = x % y;
345 if (rem == 0)
346 return x;
347 return x - rem + y;
350 /* ****************************************************************
351 * unexec
353 * driving logic.
355 * In ELF, this works by replacing the old .bss section with a new
356 * .data section, and inserting an empty .bss immediately afterwards.
359 void
360 unexec (new_name, old_name, data_start, bss_start, entry_address)
361 char *new_name, *old_name;
362 unsigned data_start, bss_start, entry_address;
364 extern unsigned int bss_end;
365 int new_file, old_file, new_file_size;
367 /* Pointers to the base of the image of the two files. */
368 caddr_t old_base, new_base;
370 /* Pointers to the file, program and section headers for the old and new
371 * files.
373 Elf32_Ehdr *old_file_h, *new_file_h;
374 Elf32_Phdr *old_program_h, *new_program_h;
375 Elf32_Shdr *old_section_h, *new_section_h;
377 /* Point to the section name table in the old file */
378 char *old_section_names;
380 Elf32_Addr old_bss_addr, new_bss_addr;
381 Elf32_Addr old_sbss_addr;
382 Elf32_Word old_bss_size, new_data2_size;
383 Elf32_Word old_sbss_size, new_data3_size;
384 Elf32_Off new_data2_offset;
385 Elf32_Off new_data3_offset;
386 Elf32_Addr new_data2_addr;
387 Elf32_Addr new_data3_addr;
390 Elf32_Addr old_rel_dyn_addr;
391 Elf32_Word old_rel_dyn_size;
392 int old_rel_dyn_index;
394 Elf32_Word old_sdata_size, new_sdata_size;
395 int old_sdata_index = 0;
397 int n, nn, old_data_index, new_data2_align;
398 int old_bss_index;
399 int old_sbss_index;
400 int old_bss_padding;
401 struct stat stat_buf;
403 /* Open the old file & map it into the address space. */
405 old_file = open (old_name, O_RDONLY);
407 if (old_file < 0)
408 fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
410 if (fstat (old_file, &stat_buf) == -1)
411 fatal ("Can't fstat(%s): errno %d\n", old_name, errno);
413 old_base = mmap (0, stat_buf.st_size, PROT_READ, MAP_SHARED, old_file, 0);
415 if (old_base == (caddr_t) -1)
416 fatal ("Can't mmap(%s): errno %d\n", old_name, errno);
418 #ifdef DEBUG
419 fprintf (stderr, "mmap(%s, %x) -> %x\n", old_name, stat_buf.st_size,
420 old_base);
421 #endif
423 /* Get pointers to headers & section names */
425 old_file_h = (Elf32_Ehdr *) old_base;
426 old_program_h = (Elf32_Phdr *) ((byte *) old_base + old_file_h->e_phoff);
427 old_section_h = (Elf32_Shdr *) ((byte *) old_base + old_file_h->e_shoff);
428 old_section_names = (char *) old_base
429 + OLD_SECTION_H(old_file_h->e_shstrndx).sh_offset;
431 /* Find the old .sbss section.
434 for (old_sbss_index = 1; old_sbss_index < old_file_h->e_shnum;
435 old_sbss_index++)
437 #ifdef DEBUG
438 fprintf (stderr, "Looking for .sbss - found %s\n",
439 old_section_names + OLD_SECTION_H(old_sbss_index).sh_name);
440 #endif
441 if (!strcmp (old_section_names + OLD_SECTION_H(old_sbss_index).sh_name,
442 ".sbss"))
443 break;
445 if (old_sbss_index == old_file_h->e_shnum)
446 fatal ("Can't find .sbss in %s.\n", old_name, 0);
448 if (!strcmp(old_section_names + OLD_SECTION_H(old_sbss_index - 1).sh_name,
449 ".sdata"))
451 old_sdata_index = old_sbss_index - 1;
455 /* Find the old .bss section.
458 for (old_bss_index = 1; old_bss_index < old_file_h->e_shnum; old_bss_index++)
460 #ifdef DEBUG
461 fprintf (stderr, "Looking for .bss - found %s\n",
462 old_section_names + OLD_SECTION_H(old_bss_index).sh_name);
463 #endif
464 if (!strcmp (old_section_names + OLD_SECTION_H(old_bss_index).sh_name,
465 ".bss"))
466 break;
468 if (old_bss_index == old_file_h->e_shnum)
469 fatal ("Can't find .bss in %s.\n", old_name, 0);
471 if (old_sbss_index != (old_bss_index - 1))
472 fatal (".sbss should come immediately before .bss in %s.\n", old_name, 0);
474 /* Find the old .rel.dyn section.
477 for (old_rel_dyn_index = 1; old_rel_dyn_index < old_file_h->e_shnum;
478 old_rel_dyn_index++)
480 #ifdef DEBUG
481 fprintf (stderr, "Looking for .rel.dyn - found %s\n",
482 old_section_names + OLD_SECTION_H(old_rel_dyn_index).sh_name);
483 #endif
484 if (!strcmp (old_section_names + OLD_SECTION_H(old_rel_dyn_index).sh_name,
485 ".rel.dyn"))
486 break;
488 if (old_rel_dyn_index == old_file_h->e_shnum)
489 fatal ("Can't find .rel_dyn in %s.\n", old_name, 0);
491 old_rel_dyn_addr = OLD_SECTION_H(old_rel_dyn_index).sh_addr;
492 old_rel_dyn_size = OLD_SECTION_H(old_rel_dyn_index).sh_size;
494 /* Figure out parameters of the new data3 and data2 sections.
495 * Change the sbss and bss sections.
498 old_bss_addr = OLD_SECTION_H(old_bss_index).sh_addr;
499 old_bss_size = OLD_SECTION_H(old_bss_index).sh_size;
501 old_sbss_addr = OLD_SECTION_H(old_sbss_index).sh_addr;
502 old_sbss_size = OLD_SECTION_H(old_sbss_index).sh_size;
504 if (old_sdata_index)
506 old_sdata_size = OLD_SECTION_H(old_sdata_index).sh_size;
509 #if defined(emacs) || !defined(DEBUG)
510 bss_end = (unsigned int) sbrk (0);
511 new_bss_addr = (Elf32_Addr) bss_end;
512 #else
513 new_bss_addr = old_bss_addr + old_bss_size + 0x1234;
514 #endif
515 if (old_sdata_index)
517 new_sdata_size = OLD_SECTION_H(old_sbss_index).sh_offset -
518 OLD_SECTION_H(old_sdata_index).sh_offset + old_sbss_size;
521 new_data3_addr = old_sbss_addr;
522 new_data3_size = old_sbss_size;
523 new_data3_offset = OLD_SECTION_H(old_sbss_index).sh_offset;
525 new_data2_addr = old_bss_addr;
526 new_data2_size = new_bss_addr - old_bss_addr;
527 new_data2_align = (new_data3_offset + old_sbss_size) %
528 OLD_SECTION_H(old_bss_index).sh_addralign;
529 new_data2_align = new_data2_align ?
530 OLD_SECTION_H(old_bss_index).sh_addralign - new_data2_align :
532 new_data2_offset = new_data3_offset + old_sbss_size + new_data2_align;
534 old_bss_padding = OLD_SECTION_H(old_bss_index).sh_offset -
535 OLD_SECTION_H(old_sbss_index).sh_offset;
536 #ifdef DEBUG
537 fprintf (stderr, "old_bss_index %d\n", old_bss_index);
538 fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
539 fprintf (stderr, "old_bss_size %x\n", old_bss_size);
540 fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
541 fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
542 fprintf (stderr, "new_data2_size %x\n", new_data2_size);
543 fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
544 fprintf (stderr, "old_sbss_index %d\n", old_sbss_index);
545 fprintf (stderr, "old_sbss_addr %x\n", old_sbss_addr);
546 fprintf (stderr, "old_sbss_size %x\n", old_sbss_size);
547 fprintf (stderr, "old_rel_dyn_addr %x\n", old_rel_dyn_addr);
548 fprintf (stderr, "old_rel_dyn_size %x\n", old_rel_dyn_size);
549 if (old_sdata_index)
551 fprintf (stderr, "old_sdata_size %x\n", old_sdata_size);
552 fprintf (stderr, "new_sdata_size %x\n", new_sdata_size);
554 else
556 fprintf (stderr, "new_data3_addr %x\n", new_data3_addr);
557 fprintf (stderr, "new_data3_size %x\n", new_data3_size);
558 fprintf (stderr, "new_data3_offset %x\n", new_data3_offset);
560 #endif
562 if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
563 fatal (".bss shrank when undumping???\n", 0, 0);
565 /* Set the output file to the right size and mmap(2) it. Set
566 * pointers to various interesting objects. stat_buf still has
567 * old_file data.
570 new_file = open (new_name, O_RDWR | O_CREAT, 0666);
571 if (new_file < 0)
572 fatal ("Can't creat(%s): errno %d\n", new_name, errno);
574 new_file_size = stat_buf.st_size +
575 ((1 + (old_sdata_index ? 0 : 1)) * old_file_h->e_shentsize) +
576 new_data2_size + new_data3_size + new_data2_align;
578 if (ftruncate (new_file, new_file_size))
579 fatal ("Can't ftruncate(%s): errno %d\n", new_name, errno);
581 new_base = mmap (0, new_file_size, PROT_READ | PROT_WRITE, MAP_SHARED,
582 new_file, 0);
584 if (new_base == (caddr_t) -1)
585 fatal ("Can't mmap(%s): errno %d\n", new_name, errno);
587 new_file_h = (Elf32_Ehdr *) new_base;
588 new_program_h = (Elf32_Phdr *) ((byte *) new_base + old_file_h->e_phoff);
589 new_section_h = (Elf32_Shdr *) ((byte *) new_base +
590 old_file_h->e_shoff +
591 new_data2_size +
592 new_data2_align +
593 new_data3_size);
595 /* Make our new file, program and section headers as copies of the
596 * originals.
599 memcpy (new_file_h, old_file_h, old_file_h->e_ehsize);
600 memcpy (new_program_h, old_program_h,
601 old_file_h->e_phnum * old_file_h->e_phentsize);
603 /* Modify the e_shstrndx if necessary. */
604 PATCH_INDEX (new_file_h->e_shstrndx);
606 /* Fix up file header. We'll add one section. Section header is
607 * further away now.
610 new_file_h->e_shoff += new_data2_size + new_data2_align + new_data3_size;
611 new_file_h->e_shnum += 1 + (old_sdata_index ? 0 : 1);
613 #ifdef DEBUG
614 fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff);
615 fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum);
616 fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff);
617 fprintf (stderr, "New section count %d\n", new_file_h->e_shnum);
618 #endif
620 /* Fix up a new program header. Extend the writable data segment so
621 * that the bss area is covered too. Find that segment by looking
622 * for a segment that ends just before the .bss area. Make sure
623 * that no segments are above the new .data2. Put a loop at the end
624 * to adjust the offset and address of any segment that is above
625 * data2, just in case we decide to allow this later.
628 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
630 /* Compute maximum of all requirements for alignment of section. */
631 int alignment = (NEW_PROGRAM_H (n)).p_align;
632 if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment)
633 alignment = OLD_SECTION_H (old_bss_index).sh_addralign;
635 if ((OLD_SECTION_H (old_sbss_index)).sh_addralign > alignment)
636 alignment = OLD_SECTION_H (old_sbss_index).sh_addralign;
638 /* Supposedly this condition is okay for the SGI. */
639 #if 0
640 if (NEW_PROGRAM_H(n).p_vaddr + NEW_PROGRAM_H(n).p_filesz > old_bss_addr)
641 fatal ("Program segment above .bss in %s\n", old_name, 0);
642 #endif
644 if (NEW_PROGRAM_H(n).p_type == PT_LOAD
645 && (round_up ((NEW_PROGRAM_H (n)).p_vaddr
646 + (NEW_PROGRAM_H (n)).p_filesz,
647 alignment)
648 == round_up (old_bss_addr, alignment)))
649 break;
651 if (n < 0)
652 fatal ("Couldn't find segment next to .bss in %s\n", old_name, 0);
654 NEW_PROGRAM_H(n).p_filesz += new_data2_size + new_data2_align +
655 new_data3_size;
656 NEW_PROGRAM_H(n).p_memsz = NEW_PROGRAM_H(n).p_filesz;
658 #if 1 /* Maybe allow section after data2 - does this ever happen? */
659 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
661 if (NEW_PROGRAM_H(n).p_vaddr
662 && NEW_PROGRAM_H(n).p_vaddr >= new_data3_addr)
663 NEW_PROGRAM_H(n).p_vaddr += new_data2_size - old_bss_size +
664 new_data3_size - old_sbss_size;
666 if (NEW_PROGRAM_H(n).p_offset >= new_data3_offset)
667 NEW_PROGRAM_H(n).p_offset += new_data2_size + new_data2_align +
668 new_data3_size;
670 #endif
672 /* Fix up section headers based on new .data2 section. Any section
673 * whose offset or virtual address is after the new .data2 section
674 * gets its value adjusted. .bss size becomes zero and new address
675 * is set. data2 section header gets added by copying the existing
676 * .data header and modifying the offset, address and size.
678 for (old_data_index = 1; old_data_index < old_file_h->e_shnum;
679 old_data_index++)
680 if (!strcmp (old_section_names + OLD_SECTION_H(old_data_index).sh_name,
681 ".data"))
682 break;
683 if (old_data_index == old_file_h->e_shnum)
684 fatal ("Can't find .data in %s.\n", old_name, 0);
686 /* Walk through all section headers, insert the new data2 section right
687 before the new bss section. */
688 for (n = 1, nn = 1; n < old_file_h->e_shnum; n++, nn++)
690 caddr_t src;
692 if (n == old_sbss_index)
694 /* If it is sbss section, insert the new data3 section before it. */
696 /* Steal the data section header for this data3 section. */
697 if (!old_sdata_index)
699 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(old_data_index),
700 new_file_h->e_shentsize);
702 NEW_SECTION_H(nn).sh_addr = new_data3_addr;
703 NEW_SECTION_H(nn).sh_offset = new_data3_offset;
704 NEW_SECTION_H(nn).sh_size = new_data3_size;
705 NEW_SECTION_H(nn).sh_flags = OLD_SECTION_H(n).sh_flags;
706 /* Use the sbss section's alignment. This will assure that the
707 new data3 section always be placed in the same spot as the old
708 sbss section by any other application. */
709 NEW_SECTION_H(nn).sh_addralign = OLD_SECTION_H(n).sh_addralign;
711 /* Now copy over what we have in the memory now. */
712 memcpy (NEW_SECTION_H(nn).sh_offset + new_base,
713 (caddr_t) OLD_SECTION_H(n).sh_addr,
714 new_data3_size);
715 /* the new .data2 section should also come before the
716 * new .sbss section */
717 nn += 2;
719 else
721 /* We always have a .sdata section: append the contents of the
722 * old .sbss section.
724 memcpy (new_data3_offset + new_base,
725 (caddr_t) OLD_SECTION_H(n).sh_addr,
726 new_data3_size);
727 nn ++;
730 else if (n == old_bss_index)
732 /* If it is bss section, insert the new data2 section before it. */
734 Elf32_Word tmp_align;
735 Elf32_Addr tmp_addr;
737 tmp_align = OLD_SECTION_H(n).sh_addralign;
738 tmp_addr = OLD_SECTION_H(n).sh_addr;
740 nn -= 2;
741 /* Steal the data section header for this data2 section. */
742 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(old_data_index),
743 new_file_h->e_shentsize);
745 NEW_SECTION_H(nn).sh_addr = new_data2_addr;
746 NEW_SECTION_H(nn).sh_offset = new_data2_offset;
747 NEW_SECTION_H(nn).sh_size = new_data2_size;
748 /* Use the bss section's alignment. This will assure that the
749 new data2 section always be placed in the same spot as the old
750 bss section by any other application. */
751 NEW_SECTION_H(nn).sh_addralign = tmp_align;
753 /* Now copy over what we have in the memory now. */
754 memcpy (NEW_SECTION_H(nn).sh_offset + new_base,
755 (caddr_t) tmp_addr, new_data2_size);
756 nn += 2;
759 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(n),
760 old_file_h->e_shentsize);
762 if (old_sdata_index && n == old_sdata_index)
763 /* The old .sdata section has now a new size */
764 NEW_SECTION_H(nn).sh_size = new_sdata_size;
766 /* The new bss section's size is zero, and its file offset and virtual
767 address should be off by NEW_DATA2_SIZE. */
768 if (n == old_sbss_index)
770 /* NN should be `old_sbss_index + 2' at this point. */
771 NEW_SECTION_H(nn).sh_offset += new_data2_size + new_data2_align +
772 new_data3_size;
773 NEW_SECTION_H(nn).sh_addr += new_data2_size + new_data2_align +
774 new_data3_size;
775 /* Let the new bss section address alignment be the same as the
776 section address alignment followed the old bss section, so
777 this section will be placed in exactly the same place. */
778 NEW_SECTION_H(nn).sh_addralign =
779 OLD_SECTION_H(nn + (old_sdata_index ? 1 : 0)).sh_addralign;
780 NEW_SECTION_H(nn).sh_size = 0;
782 else if (n == old_bss_index)
784 /* NN should be `old_bss_index + 2' at this point. */
785 NEW_SECTION_H(nn).sh_offset += new_data2_size + new_data2_align +
786 new_data3_size - old_bss_padding;
787 NEW_SECTION_H(nn).sh_addr += new_data2_size;
788 /* Let the new bss section address alignment be the same as the
789 section address alignment followed the old bss section, so
790 this section will be placed in exactly the same place. */
791 NEW_SECTION_H(nn).sh_addralign =
792 OLD_SECTION_H((nn - (old_sdata_index ? 0 : 1))).sh_addralign;
793 NEW_SECTION_H(nn).sh_size = 0;
795 /* Any section that was original placed AFTER the bss section should now
796 be off by NEW_DATA2_SIZE. */
797 else if (NEW_SECTION_H(nn).sh_offset >= new_data3_offset)
798 NEW_SECTION_H(nn).sh_offset += new_data2_size +
799 new_data2_align +
800 new_data3_size -
801 old_bss_padding;
803 /* If any section hdr refers to the section after the new .data
804 section, make it refer to next one because we have inserted
805 a new section in between. */
807 PATCH_INDEX(NEW_SECTION_H(nn).sh_link);
808 PATCH_INDEX(NEW_SECTION_H(nn).sh_info);
810 /* Now, start to copy the content of sections. */
811 if (NEW_SECTION_H(nn).sh_type == SHT_NULL
812 || NEW_SECTION_H(nn).sh_type == SHT_NOBITS)
813 continue;
815 /* Write out the sections. .data, .data1 and .sdata get copied from
816 * the current process instead of the old file.
818 if (!strcmp (old_section_names + OLD_SECTION_H(n).sh_name, ".data") ||
819 !strcmp (old_section_names + OLD_SECTION_H(n).sh_name, ".data1") ||
820 (old_sdata_index && (n == old_sdata_index)))
821 src = (caddr_t) OLD_SECTION_H(n).sh_addr;
822 else
823 src = old_base + OLD_SECTION_H(n).sh_offset;
825 memcpy (NEW_SECTION_H(nn).sh_offset + new_base, src,
826 ((n == old_sdata_index) ?
827 old_sdata_size :
828 NEW_SECTION_H(nn).sh_size));
830 /* If it is the symbol table, its st_shndx field needs to be patched. */
831 if (NEW_SECTION_H(nn).sh_type == SHT_SYMTAB
832 || NEW_SECTION_H(nn).sh_type == SHT_DYNSYM)
834 Elf32_Shdr *spt = &NEW_SECTION_H(nn);
835 unsigned int num = spt->sh_size / spt->sh_entsize;
836 Elf32_Sym * sym = (Elf32_Sym *) (NEW_SECTION_H(nn).sh_offset +
837 new_base);
838 for (; num--; sym++)
840 if ((sym->st_shndx == SHN_UNDEF)
841 || (sym->st_shndx == SHN_ABS)
842 || (sym->st_shndx == SHN_COMMON))
843 continue;
845 PATCH_INDEX(sym->st_shndx);
850 Elf32_Rel *rel_p;
851 unsigned int old_data_addr_start;
852 unsigned int old_data_addr_end;
853 unsigned int old_data_offset;
854 unsigned int new_data_offset;
855 int i;
857 rel_p = (Elf32_Rel *)OLD_SECTION_H(old_rel_dyn_index).sh_addr;
858 old_data_addr_start = OLD_SECTION_H(old_data_index).sh_addr;
859 old_data_addr_end = old_data_addr_start +
860 OLD_SECTION_H(old_data_index).sh_size;
861 old_data_offset = (int)OLD_SECTION_H(old_data_index).sh_offset +
862 (unsigned int)old_base;
863 new_data_offset = (int)NEW_SECTION_H(old_data_index).sh_offset +
864 (unsigned int)new_base;
866 #ifdef DEBUG
867 fprintf(stderr, "old_data.sh_addr= 0x%08x ... 0x%08x\n", old_data_addr_start,
868 old_data_addr_end);
869 #endif /* DEBUG */
871 for (i = 0; i < old_rel_dyn_size/sizeof(Elf32_Rel); i++)
873 #ifdef DEBUG
874 fprintf(stderr, ".rel.dyn offset= 0x%08x type= %d sym= %d\n",
875 rel_p->r_offset, ELF32_R_TYPE(rel_p->r_info), ELF32_R_SYM(rel_p->r_info));
876 #endif /* DEBUG */
878 if (rel_p->r_offset)
880 unsigned int offset;
882 assert(old_data_addr_start <= rel_p->r_offset &&
883 rel_p->r_offset <= old_data_addr_end);
885 offset = rel_p->r_offset - old_data_addr_start;
887 #ifdef DEBUG
888 fprintf(stderr, "r_offset= 0x%08x *r_offset= 0x%08x\n",
889 rel_p->r_offset, *((int *)(rel_p->r_offset)));
890 fprintf(stderr, "old = 0x%08x *old =0x%08x\n",
891 (old_data_offset + offset - (unsigned int)old_base),
892 *((int *)(old_data_offset + offset)));
893 fprintf(stderr, "new = 0x%08x *new =0x%08x\n",
894 (new_data_offset + offset - (unsigned int)new_base),
895 *((int *)(new_data_offset + offset)));
896 #endif /* DEBUG */
898 *((int *)(new_data_offset + offset)) = *((int *)(old_data_offset + offset));
901 rel_p++;
905 /* Close the files and make the new file executable */
907 if (close (old_file))
908 fatal ("Can't close(%s): errno %d\n", old_name, errno);
910 if (close (new_file))
911 fatal ("Can't close(%s): errno %d\n", new_name, errno);
913 if (stat (new_name, &stat_buf) == -1)
914 fatal ("Can't stat(%s): errno %d\n", new_name, errno);
916 n = umask (777);
917 umask (n);
918 stat_buf.st_mode |= 0111 & ~n;
919 if (chmod (new_name, stat_buf.st_mode) == -1)
920 fatal ("Can't chmod(%s): errno %d\n", new_name, errno);
923 /* arch-tag: c784ead3-7a27-442b-83fe-7af8d08654d3
924 (do not change this comment) */