Update FSF's address in the preamble.
[bpt/emacs.git] / src / unexsni.c
CommitLineData
f1913a26 1/* Unexec for Siemens machines running Sinix (modified SVR4).
f8c25f1b 2 Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992, 1993, 1994, 1995
f1913a26
RS
3 Free Software Foundation, Inc.
4
3b7ad313 5This file is part of GNU Emacs.
f1913a26 6
3b7ad313
EN
7GNU Emacs is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 2, or (at your option)
10any later version.
f1913a26 11
3b7ad313
EN
12GNU Emacs is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GNU Emacs; see the file COPYING. If not, write to
19the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20Boston, MA 02111-1307, USA.
f1913a26
RS
21
22In other words, you are welcome to use, share and improve this program.
23You are forbidden to forbid anyone else to use, share and improve
24what you give them. Help stamp out software-hoarding! */
25
26
27/*
28 * unexec.c - Convert a running program into an a.out file.
29 *
30 * Author: Spencer W. Thomas
31 * Computer Science Dept.
32 * University of Utah
33 * Date: Tue Mar 2 1982
34 * Modified heavily since then.
35 *
36 * Synopsis:
37 * unexec (new_name, a_name, data_start, bss_start, entry_address)
38 * char *new_name, *a_name;
39 * unsigned data_start, bss_start, entry_address;
40 *
41 * Takes a snapshot of the program and makes an a.out format file in the
42 * file named by the string argument new_name.
43 * If a_name is non-NULL, the symbol table will be taken from the given file.
44 * On some machines, an existing a_name file is required.
45 *
46 * The boundaries within the a.out file may be adjusted with the data_start
47 * and bss_start arguments. Either or both may be given as 0 for defaults.
48 *
49 * Data_start gives the boundary between the text segment and the data
50 * segment of the program. The text segment can contain shared, read-only
51 * program code and literal data, while the data segment is always unshared
52 * and unprotected. Data_start gives the lowest unprotected address.
53 * The value you specify may be rounded down to a suitable boundary
54 * as required by the machine you are using.
55 *
56 * Specifying zero for data_start means the boundary between text and data
57 * should not be the same as when the program was loaded.
58 * If NO_REMAP is defined, the argument data_start is ignored and the
59 * segment boundaries are never changed.
60 *
61 * Bss_start indicates how much of the data segment is to be saved in the
62 * a.out file and restored when the program is executed. It gives the lowest
63 * unsaved address, and is rounded up to a page boundary. The default when 0
64 * is given assumes that the entire data segment is to be stored, including
65 * the previous data and bss as well as any additional storage allocated with
66 * break (2).
67 *
68 * The new file is set up to start at entry_address.
69 *
70 * If you make improvements I'd like to get them too.
71 * harpo!utah-cs!thomas, thomas@Utah-20
72 *
73 */
74
75/* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
76 * ELF support added.
77 *
78 * Basic theory: the data space of the running process needs to be
79 * dumped to the output file. Normally we would just enlarge the size
80 * of .data, scooting everything down. But we can't do that in ELF,
81 * because there is often something between the .data space and the
82 * .bss space.
83 *
84 * In the temacs dump below, notice that the Global Offset Table
85 * (.got) and the Dynamic link data (.dynamic) come between .data1 and
86 * .bss. It does not work to overlap .data with these fields.
87 *
88 * The solution is to create a new .data segment. This segment is
89 * filled with data from the current process. Since the contents of
90 * various sections refer to sections by index, the new .data segment
91 * is made the last in the table to avoid changing any existing index.
92 */
93
94/* Modified by wtien@urbana.mcd.mot.com of Motorola Inc.
95 *
96 * The above mechanism does not work if the unexeced ELF file is being
97 * re-layout by other applications (such as `strip'). All the applications
98 * that re-layout the internal of ELF will layout all sections in ascending
99 * order of their file offsets. After the re-layout, the data2 section will
100 * still be the LAST section in the section header vector, but its file offset
101 * is now being pushed far away down, and causes part of it not to be mapped
102 * in (ie. not covered by the load segment entry in PHDR vector), therefore
103 * causes the new binary to fail.
104 *
105 * The solution is to modify the unexec algorithm to insert the new data2
106 * section header right before the new bss section header, so their file
107 * offsets will be in the ascending order. Since some of the section's (all
108 * sections AFTER the bss section) indexes are now changed, we also need to
109 * modify some fields to make them point to the right sections. This is done
110 * by macro PATCH_INDEX. All the fields that need to be patched are:
111 *
112 * 1. ELF header e_shstrndx field.
113 * 2. section header sh_link and sh_info field.
114 * 3. symbol table entry st_shndx field.
115 */
116
117/*
118 * New modifications for Siemens Nixdorf's MIPS-based machines.
119 * Marco.Walther@mch.sni.de
120 *
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.
124 *
125 * /home1/marco/emacs/emacs-19.22/src
126 * dump -hv temacs
127 *
128 * temacs:
129 *
130 * **** SECTION HEADER TABLE ****
131 * [No] Type Flags Addr Offset Size Name
132 * Link Info Adralgn Entsize
133 *
134 * [1] PBIT -A-- 0x4000f4 0xf4 0x13 .interp
135 * 0 0 0x1 0
136 *
137 * [2] REGI -A-- 0x400108 0x108 0x18 .reginfo
138 * 0 0 0x4 0x18
139 *
140 * [3] DYNM -A-- 0x400120 0x120 0xb8 .dynamic
141 * 6 0 0x4 0x8
142 *
143 * [4] HASH -A-- 0x4001d8 0x1d8 0x8a0 .hash
144 * 5 0 0x4 0x4
145 *
146 * [5] DYNS -A-- 0x400a78 0xa78 0x11f0 .dynsym
147 * 6 2 0x4 0x10
148 *
149 * [6] STRT -A-- 0x401c68 0x1c68 0xbf9 .dynstr
150 * 0 0 0x1 0
151 *
152 * [7] REL -A-- 0x402864 0x2864 0x18 .rel.dyn
153 * 5 14 0x4 0x8
154 *
155 * [8] PBIT -AI- 0x402880 0x2880 0x60 .init
156 * 0 0 0x10 0x1
157 *
158 * [9] PBIT -AI- 0x4028e0 0x28e0 0x1234 .plt
159 * 0 0 0x4 0x4
160 *
161 * [10] PBIT -AI- 0x403b20 0x3b20 0xee400 .text
162 * 0 0 0x20 0x1
163 *
164 * [11] PBIT -AI- 0x4f1f20 0xf1f20 0x60 .fini
165 * 0 0 0x10 0x1
166 *
167 * [12] PBIT -A-- 0x4f1f80 0xf1f80 0xd90 .rdata
168 * 0 0 0x10 0x1
169 *
170 * [13] PBIT -A-- 0x4f2d10 0xf2d10 0x17e0 .rodata
171 * 0 0 0x10 0x1
172 *
173 * [14] PBIT WA-- 0x5344f0 0xf44f0 0x4b3e4 .data <<<<<
174 * 0 0 0x10 0x1
175 *
176 * [15] PBIT WA-G 0x57f8d4 0x13f8d4 0x2a84 .got
177 * 0 0 0x4 0x4
178 *
179 * [16] PBIT WA-G 0x582360 0x142360 0x10 .sdata <<<<<
180 * 0 0 0x10 0x1
181 *
182 * [17] NOBI WA-G 0x582370 0x142370 0xb84 .sbss <<<<<
183 * 0 0 0x4 0
184 *
185 * [18] NOBI WA-- 0x582f00 0x142370 0x27ec0 .bss <<<<<
186 * 0 0 0x10 0x1
187 *
188 * [19] SYMT ---- 0 0x142370 0x10e40 .symtab
189 * 20 1108 0x4 0x10
190 *
191 * [20] STRT ---- 0 0x1531b0 0xed9e .strtab
192 * 0 0 0x1 0
193 *
194 * [21] STRT ---- 0 0x161f4e 0xb5 .shstrtab
195 * 0 0 0x1 0
196 *
197 * [22] PBIT ---- 0 0x162003 0x28e2a .comment
198 * 0 0 0x1 0x1
199 *
200 * [23] PBIT ---- 0 0x18ae2d 0x592 .debug
201 * 0 0 0x1 0
202 *
203 * [24] PBIT ---- 0 0x18b3bf 0x80 .line
204 * 0 0 0x1 0
205 *
206 * [25] MDBG ---- 0 0x18b440 0x60 .mdebug
207 * 0 0 0x4 0
208 *
209 *
210 * dump -hv emacs
211 *
212 * emacs:
213 *
214 * **** SECTION HEADER TABLE ****
215 * [No] Type Flags Addr Offset Size Name
216 * Link Info Adralgn Entsize
217 *
218 * [1] PBIT -A-- 0x4000f4 0xf4 0x13 .interp
219 * 0 0 0x1 0
220 *
221 * [2] REGI -A-- 0x400108 0x108 0x18 .reginfo
222 * 0 0 0x4 0x18
223 *
224 * [3] DYNM -A-- 0x400120 0x120 0xb8 .dynamic
225 * 6 0 0x4 0x8
226 *
227 * [4] HASH -A-- 0x4001d8 0x1d8 0x8a0 .hash
228 * 5 0 0x4 0x4
229 *
230 * [5] DYNS -A-- 0x400a78 0xa78 0x11f0 .dynsym
231 * 6 2 0x4 0x10
232 *
233 * [6] STRT -A-- 0x401c68 0x1c68 0xbf9 .dynstr
234 * 0 0 0x1 0
235 *
236 * [7] REL -A-- 0x402864 0x2864 0x18 .rel.dyn
237 * 5 14 0x4 0x8
238 *
239 * [8] PBIT -AI- 0x402880 0x2880 0x60 .init
240 * 0 0 0x10 0x1
241 *
242 * [9] PBIT -AI- 0x4028e0 0x28e0 0x1234 .plt
243 * 0 0 0x4 0x4
244 *
245 * [10] PBIT -AI- 0x403b20 0x3b20 0xee400 .text
246 * 0 0 0x20 0x1
247 *
248 * [11] PBIT -AI- 0x4f1f20 0xf1f20 0x60 .fini
249 * 0 0 0x10 0x1
250 *
251 * [12] PBIT -A-- 0x4f1f80 0xf1f80 0xd90 .rdata
252 * 0 0 0x10 0x1
253 *
254 * [13] PBIT -A-- 0x4f2d10 0xf2d10 0x17e0 .rodata
255 * 0 0 0x10 0x1
256 *
257 * [14] PBIT WA-- 0x5344f0 0xf44f0 0x4b3e4 .data <<<<<
258 * 0 0 0x10 0x1
259 *
260 * [15] PBIT WA-G 0x57f8d4 0x13f8d4 0x2a84 .got
261 * 0 0 0x4 0x4
262 *
263 * [16] PBIT WA-G 0x582360 0x142360 0xb94 .sdata <<<<<
264 * 0 0 0x10 0x1
265 *
266 * [17] PBIT WA-- 0x582f00 0x142f00 0x94100 .data <<<<<
267 * 0 0 0x10 0x1
268 *
269 * [18] NOBI WA-G 0x617000 0x1d7000 0 .sbss <<<<<
270 * 0 0 0x4 0
271 *
272 * [19] NOBI WA-- 0x617000 0x1d7000 0 .bss <<<<<
273 * 0 0 0x4 0x1
274 *
275 * [20] SYMT ---- 0 0x1d7000 0x10e40 .symtab
276 * 21 1109 0x4 0x10
277 *
278 * [21] STRT ---- 0 0x1e7e40 0xed9e .strtab
279 * 0 0 0x1 0
280 *
281 * [22] STRT ---- 0 0x1f6bde 0xb5 .shstrtab
282 * 0 0 0x1 0
283 *
284 * [23] PBIT ---- 0 0x1f6c93 0x28e2a .comment
285 * 0 0 0x1 0x1
286 *
287 * [24] PBIT ---- 0 0x21fabd 0x592 .debug
288 * 0 0 0x1 0
289 *
290 * [25] PBIT ---- 0 0x22004f 0x80 .line
291 * 0 0 0x1 0
292 *
293 * [26] MDBG ---- 0 0x2200d0 0x60 .mdebug
294 * 0 0 0x4 0
295 *
296 */
297\f
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
309#ifndef emacs
310#define fatal(a, b, c) fprintf(stderr, a, b, c), exit(1)
311#else
312extern void fatal(char *, ...);
313#endif
314
315/* Get the address of a particular section or program header entry,
316 * accounting for the size of the entries.
317 */
318
319#define OLD_SECTION_H(n) \
320 (*(Elf32_Shdr *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
321#define NEW_SECTION_H(n) \
322 (*(Elf32_Shdr *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
323#define OLD_PROGRAM_H(n) \
324 (*(Elf32_Phdr *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
325#define NEW_PROGRAM_H(n) \
326 (*(Elf32_Phdr *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
327
328#define PATCH_INDEX(n) \
329 do { \
330 if ((n) >= old_sbss_index) \
331 (n) += 1 + (old_sdata_index ? 0 : 1); } while (0)
332
333typedef unsigned char byte;
334
335/* Round X up to a multiple of Y. */
336
337int
338round_up (x, y)
339 int x, y;
340{
341 int rem = x % y;
342 if (rem == 0)
343 return x;
344 return x - rem + y;
345}
346
347/* ****************************************************************
348 * unexec
349 *
350 * driving logic.
351 *
352 * In ELF, this works by replacing the old .bss section with a new
353 * .data section, and inserting an empty .bss immediately afterwards.
354 *
355 */
356void
357unexec (new_name, old_name, data_start, bss_start, entry_address)
358 char *new_name, *old_name;
359 unsigned data_start, bss_start, entry_address;
360{
361 extern unsigned int bss_end;
362 int new_file, old_file, new_file_size;
363
364 /* Pointers to the base of the image of the two files. */
365 caddr_t old_base, new_base;
366
367 /* Pointers to the file, program and section headers for the old and new
368 * files.
369 */
370 Elf32_Ehdr *old_file_h, *new_file_h;
371 Elf32_Phdr *old_program_h, *new_program_h;
372 Elf32_Shdr *old_section_h, *new_section_h;
373
374 /* Point to the section name table in the old file */
375 char *old_section_names;
376
377 Elf32_Addr old_bss_addr, new_bss_addr;
378 Elf32_Addr old_sbss_addr;
379 Elf32_Word old_bss_size, new_data2_size;
380 Elf32_Word old_sbss_size, new_data3_size;
381 Elf32_Off new_data2_offset;
382 Elf32_Off new_data3_offset;
383 Elf32_Addr new_data2_addr;
384 Elf32_Addr new_data3_addr;
385
386 Elf32_Word old_sdata_size, new_sdata_size;
387 int old_sdata_index = 0;
388
389 int n, nn, old_data_index, new_data2_align;
390 int old_bss_index;
391 int old_sbss_index;
392 int old_bss_padding;
393 struct stat stat_buf;
394
395 /* Open the old file & map it into the address space. */
396
397 old_file = open (old_name, O_RDONLY);
398
399 if (old_file < 0)
400 fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
401
402 if (fstat (old_file, &stat_buf) == -1)
403 fatal ("Can't fstat(%s): errno %d\n", old_name, errno);
404
405 old_base = mmap (0, stat_buf.st_size, PROT_READ, MAP_SHARED, old_file, 0);
406
407 if (old_base == (caddr_t) -1)
408 fatal ("Can't mmap(%s): errno %d\n", old_name, errno);
409
410#ifdef DEBUG
411 fprintf (stderr, "mmap(%s, %x) -> %x\n", old_name, stat_buf.st_size,
412 old_base);
413#endif
414
415 /* Get pointers to headers & section names */
416
417 old_file_h = (Elf32_Ehdr *) old_base;
418 old_program_h = (Elf32_Phdr *) ((byte *) old_base + old_file_h->e_phoff);
419 old_section_h = (Elf32_Shdr *) ((byte *) old_base + old_file_h->e_shoff);
420 old_section_names = (char *) old_base
421 + OLD_SECTION_H(old_file_h->e_shstrndx).sh_offset;
422
423 /* Find the old .sbss section.
424 */
425
426 for (old_sbss_index = 1; old_sbss_index < old_file_h->e_shnum;
427 old_sbss_index++)
428 {
429#ifdef DEBUG
430 fprintf (stderr, "Looking for .sbss - found %s\n",
431 old_section_names + OLD_SECTION_H(old_sbss_index).sh_name);
432#endif
433 if (!strcmp (old_section_names + OLD_SECTION_H(old_sbss_index).sh_name,
434 ".sbss"))
435 break;
436 }
437 if (old_sbss_index == old_file_h->e_shnum)
438 fatal ("Can't find .sbss in %s.\n", old_name, 0);
439
440 if (!strcmp(old_section_names + OLD_SECTION_H(old_sbss_index - 1).sh_name,
441 ".sdata"))
442 {
443 old_sdata_index = old_sbss_index - 1;
444 }
445
446
447 /* Find the old .bss section.
448 */
449
450 for (old_bss_index = 1; old_bss_index < old_file_h->e_shnum; old_bss_index++)
451 {
452#ifdef DEBUG
453 fprintf (stderr, "Looking for .bss - found %s\n",
454 old_section_names + OLD_SECTION_H(old_bss_index).sh_name);
455#endif
456 if (!strcmp (old_section_names + OLD_SECTION_H(old_bss_index).sh_name,
457 ".bss"))
458 break;
459 }
460 if (old_bss_index == old_file_h->e_shnum)
461 fatal ("Can't find .bss in %s.\n", old_name, 0);
462
463 if (old_sbss_index != (old_bss_index - 1))
b75dac61 464 fatal (".sbss should come immediately before .bss in %s.\n", old_name, 0);
f1913a26
RS
465
466 /* Figure out parameters of the new data3 and data2 sections.
467 * Change the sbss and bss sections.
468 */
469
470 old_bss_addr = OLD_SECTION_H(old_bss_index).sh_addr;
471 old_bss_size = OLD_SECTION_H(old_bss_index).sh_size;
472
473 old_sbss_addr = OLD_SECTION_H(old_sbss_index).sh_addr;
474 old_sbss_size = OLD_SECTION_H(old_sbss_index).sh_size;
475
476 if (old_sdata_index)
477 {
478 old_sdata_size = OLD_SECTION_H(old_sdata_index).sh_size;
479 }
480
481#if defined(emacs) || !defined(DEBUG)
482 bss_end = (unsigned int) sbrk (0);
483 new_bss_addr = (Elf32_Addr) bss_end;
484#else
485 new_bss_addr = old_bss_addr + old_bss_size + 0x1234;
486#endif
487 if (old_sdata_index)
488 {
489 new_sdata_size = OLD_SECTION_H(old_sbss_index).sh_offset -
490 OLD_SECTION_H(old_sdata_index).sh_offset + old_sbss_size;
491 }
492
493 new_data3_addr = old_sbss_addr;
494 new_data3_size = old_sbss_size;
495 new_data3_offset = OLD_SECTION_H(old_sbss_index).sh_offset;
496
497 new_data2_addr = old_bss_addr;
498 new_data2_size = new_bss_addr - old_bss_addr;
499 new_data2_align = (new_data3_offset + old_sbss_size) %
500 OLD_SECTION_H(old_bss_index).sh_addralign;
501 new_data2_align = new_data2_align ?
502 OLD_SECTION_H(old_bss_index).sh_addralign - new_data2_align :
503 0;
504 new_data2_offset = new_data3_offset + old_sbss_size + new_data2_align;
505
506 old_bss_padding = OLD_SECTION_H(old_bss_index).sh_offset -
507 OLD_SECTION_H(old_sbss_index).sh_offset;
508#ifdef DEBUG
509 fprintf (stderr, "old_bss_index %d\n", old_bss_index);
510 fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
511 fprintf (stderr, "old_bss_size %x\n", old_bss_size);
512 fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
513 fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
514 fprintf (stderr, "new_data2_size %x\n", new_data2_size);
515 fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
516 fprintf (stderr, "old_sbss_index %d\n", old_sbss_index);
517 fprintf (stderr, "old_sbss_addr %x\n", old_sbss_addr);
518 fprintf (stderr, "old_sbss_size %x\n", old_sbss_size);
519 if (old_sdata_index)
520 {
521 fprintf (stderr, "old_sdata_size %x\n", old_sdata_size);
522 fprintf (stderr, "new_sdata_size %x\n", new_sdata_size);
523 }
524 else
525 {
526 fprintf (stderr, "new_data3_addr %x\n", new_data3_addr);
527 fprintf (stderr, "new_data3_size %x\n", new_data3_size);
528 fprintf (stderr, "new_data3_offset %x\n", new_data3_offset);
529 }
530#endif
531
532 if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
533 fatal (".bss shrank when undumping???\n", 0, 0);
534
535 /* Set the output file to the right size and mmap(2) it. Set
536 * pointers to various interesting objects. stat_buf still has
537 * old_file data.
538 */
539
540 new_file = open (new_name, O_RDWR | O_CREAT, 0666);
541 if (new_file < 0)
542 fatal ("Can't creat(%s): errno %d\n", new_name, errno);
543
544 new_file_size = stat_buf.st_size +
545 ((1 + (old_sdata_index ? 0 : 1)) * old_file_h->e_shentsize) +
546 new_data2_size + new_data3_size + new_data2_align;
547
548 if (ftruncate (new_file, new_file_size))
549 fatal ("Can't ftruncate(%s): errno %d\n", new_name, errno);
550
551 new_base = mmap (0, new_file_size, PROT_READ | PROT_WRITE, MAP_SHARED,
552 new_file, 0);
553
554 if (new_base == (caddr_t) -1)
555 fatal ("Can't mmap(%s): errno %d\n", new_name, errno);
556
557 new_file_h = (Elf32_Ehdr *) new_base;
558 new_program_h = (Elf32_Phdr *) ((byte *) new_base + old_file_h->e_phoff);
559 new_section_h = (Elf32_Shdr *) ((byte *) new_base +
560 old_file_h->e_shoff +
561 new_data2_size +
562 new_data2_align +
563 new_data3_size);
564
565 /* Make our new file, program and section headers as copies of the
566 * originals.
567 */
568
569 memcpy (new_file_h, old_file_h, old_file_h->e_ehsize);
570 memcpy (new_program_h, old_program_h,
571 old_file_h->e_phnum * old_file_h->e_phentsize);
572
573 /* Modify the e_shstrndx if necessary. */
574 PATCH_INDEX (new_file_h->e_shstrndx);
575
576 /* Fix up file header. We'll add one section. Section header is
577 * further away now.
578 */
579
580 new_file_h->e_shoff += new_data2_size + new_data2_align + new_data3_size;
581 new_file_h->e_shnum += 1 + (old_sdata_index ? 0 : 1);
582
583#ifdef DEBUG
584 fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff);
585 fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum);
586 fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff);
587 fprintf (stderr, "New section count %d\n", new_file_h->e_shnum);
588#endif
589
590 /* Fix up a new program header. Extend the writable data segment so
591 * that the bss area is covered too. Find that segment by looking
592 * for a segment that ends just before the .bss area. Make sure
593 * that no segments are above the new .data2. Put a loop at the end
594 * to adjust the offset and address of any segment that is above
595 * data2, just in case we decide to allow this later.
596 */
597
598 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
599 {
600 /* Compute maximum of all requirements for alignment of section. */
601 int alignment = (NEW_PROGRAM_H (n)).p_align;
602 if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment)
603 alignment = OLD_SECTION_H (old_bss_index).sh_addralign;
604
605 if ((OLD_SECTION_H (old_sbss_index)).sh_addralign > alignment)
606 alignment = OLD_SECTION_H (old_sbss_index).sh_addralign;
607
608 /* Supposedly this condition is okay for the SGI. */
609#if 0
610 if (NEW_PROGRAM_H(n).p_vaddr + NEW_PROGRAM_H(n).p_filesz > old_bss_addr)
611 fatal ("Program segment above .bss in %s\n", old_name, 0);
612#endif
613
614 if (NEW_PROGRAM_H(n).p_type == PT_LOAD
615 && (round_up ((NEW_PROGRAM_H (n)).p_vaddr
616 + (NEW_PROGRAM_H (n)).p_filesz,
617 alignment)
618 == round_up (old_bss_addr, alignment)))
619 break;
620 }
621 if (n < 0)
622 fatal ("Couldn't find segment next to .bss in %s\n", old_name, 0);
623
624 NEW_PROGRAM_H(n).p_filesz += new_data2_size + new_data2_align +
625 new_data3_size;
626 NEW_PROGRAM_H(n).p_memsz = NEW_PROGRAM_H(n).p_filesz;
627
628#if 1 /* Maybe allow section after data2 - does this ever happen? */
629 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
630 {
631 if (NEW_PROGRAM_H(n).p_vaddr
632 && NEW_PROGRAM_H(n).p_vaddr >= new_data3_addr)
633 NEW_PROGRAM_H(n).p_vaddr += new_data2_size - old_bss_size +
634 new_data3_size - old_sbss_size;
635
636 if (NEW_PROGRAM_H(n).p_offset >= new_data3_offset)
637 NEW_PROGRAM_H(n).p_offset += new_data2_size + new_data2_align +
638 new_data3_size;
639 }
640#endif
641
642 /* Fix up section headers based on new .data2 section. Any section
643 * whose offset or virtual address is after the new .data2 section
644 * gets its value adjusted. .bss size becomes zero and new address
645 * is set. data2 section header gets added by copying the existing
646 * .data header and modifying the offset, address and size.
647 */
648 for (old_data_index = 1; old_data_index < old_file_h->e_shnum;
649 old_data_index++)
650 if (!strcmp (old_section_names + OLD_SECTION_H(old_data_index).sh_name,
651 ".data"))
652 break;
653 if (old_data_index == old_file_h->e_shnum)
654 fatal ("Can't find .data in %s.\n", old_name, 0);
655
656 /* Walk through all section headers, insert the new data2 section right
657 before the new bss section. */
658 for (n = 1, nn = 1; n < old_file_h->e_shnum; n++, nn++)
659 {
660 caddr_t src;
661
662 if (n == old_sbss_index)
663
664 /* If it is sbss section, insert the new data3 section before it. */
665 {
666 /* Steal the data section header for this data3 section. */
667 if (!old_sdata_index)
668 {
669 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(old_data_index),
670 new_file_h->e_shentsize);
671
672 NEW_SECTION_H(nn).sh_addr = new_data3_addr;
673 NEW_SECTION_H(nn).sh_offset = new_data3_offset;
674 NEW_SECTION_H(nn).sh_size = new_data3_size;
675 NEW_SECTION_H(nn).sh_flags = OLD_SECTION_H(n).sh_flags;
676 /* Use the sbss section's alignment. This will assure that the
677 new data3 section always be placed in the same spot as the old
678 sbss section by any other application. */
679 NEW_SECTION_H(nn).sh_addralign = OLD_SECTION_H(n).sh_addralign;
680
681 /* Now copy over what we have in the memory now. */
682 memcpy (NEW_SECTION_H(nn).sh_offset + new_base,
683 (caddr_t) OLD_SECTION_H(n).sh_addr,
684 new_data3_size);
685 /* the new .data2 section should also come before the
686 * new .sbss section */
687 nn += 2;
688 }
689 else
690 {
691 /* We always have a .sdata section: append the contents of the
692 * old .sbss section.
693 */
694 memcpy (new_data3_offset + new_base,
695 (caddr_t) OLD_SECTION_H(n).sh_addr,
696 new_data3_size);
697 nn ++;
698 }
699 }
700 else if (n == old_bss_index)
701
702 /* If it is bss section, insert the new data2 section before it. */
703 {
704 Elf32_Word tmp_align;
705 Elf32_Addr tmp_addr;
706
707 tmp_align = OLD_SECTION_H(n).sh_addralign;
708 tmp_addr = OLD_SECTION_H(n).sh_addr;
709
710 nn -= 2;
711 /* Steal the data section header for this data2 section. */
712 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(old_data_index),
713 new_file_h->e_shentsize);
714
715 NEW_SECTION_H(nn).sh_addr = new_data2_addr;
716 NEW_SECTION_H(nn).sh_offset = new_data2_offset;
717 NEW_SECTION_H(nn).sh_size = new_data2_size;
718 /* Use the bss section's alignment. This will assure that the
719 new data2 section always be placed in the same spot as the old
720 bss section by any other application. */
721 NEW_SECTION_H(nn).sh_addralign = tmp_align;
722
723 /* Now copy over what we have in the memory now. */
724 memcpy (NEW_SECTION_H(nn).sh_offset + new_base,
725 (caddr_t) tmp_addr, new_data2_size);
726 nn += 2;
727 }
728
729 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(n),
730 old_file_h->e_shentsize);
731
732 if (old_sdata_index && n == old_sdata_index)
733 /* The old .sdata section has now a new size */
734 NEW_SECTION_H(nn).sh_size = new_sdata_size;
735
736 /* The new bss section's size is zero, and its file offset and virtual
737 address should be off by NEW_DATA2_SIZE. */
738 if (n == old_sbss_index)
739 {
740 /* NN should be `old_sbss_index + 2' at this point. */
741 NEW_SECTION_H(nn).sh_offset += new_data2_size + new_data2_align +
742 new_data3_size;
743 NEW_SECTION_H(nn).sh_addr += new_data2_size + new_data2_align +
744 new_data3_size;
745 /* Let the new bss section address alignment be the same as the
746 section address alignment followed the old bss section, so
747 this section will be placed in exactly the same place. */
748 NEW_SECTION_H(nn).sh_addralign =
749 OLD_SECTION_H(nn + (old_sdata_index ? 1 : 0)).sh_addralign;
750 NEW_SECTION_H(nn).sh_size = 0;
751 }
752 else if (n == old_bss_index)
753 {
754 /* NN should be `old_bss_index + 2' at this point. */
755 NEW_SECTION_H(nn).sh_offset += new_data2_size + new_data2_align +
756 new_data3_size - old_bss_padding;
757 NEW_SECTION_H(nn).sh_addr += new_data2_size;
758 /* Let the new bss section address alignment be the same as the
759 section address alignment followed the old bss section, so
760 this section will be placed in exactly the same place. */
761 NEW_SECTION_H(nn).sh_addralign =
762 OLD_SECTION_H((nn - (old_sdata_index ? 0 : 1))).sh_addralign;
763 NEW_SECTION_H(nn).sh_size = 0;
764 }
765 /* Any section that was original placed AFTER the bss section should now
766 be off by NEW_DATA2_SIZE. */
767 else if (NEW_SECTION_H(nn).sh_offset >= new_data3_offset)
768 NEW_SECTION_H(nn).sh_offset += new_data2_size +
769 new_data2_align +
770 new_data3_size -
771 old_bss_padding;
772
773 /* If any section hdr refers to the section after the new .data
774 section, make it refer to next one because we have inserted
775 a new section in between. */
776
777 PATCH_INDEX(NEW_SECTION_H(nn).sh_link);
778 PATCH_INDEX(NEW_SECTION_H(nn).sh_info);
779
780 /* Now, start to copy the content of sections. */
781 if (NEW_SECTION_H(nn).sh_type == SHT_NULL
782 || NEW_SECTION_H(nn).sh_type == SHT_NOBITS)
783 continue;
784
785 /* Write out the sections. .data, .data1 and .sdata get copied from
786 * the current process instead of the old file.
787 */
788 if (!strcmp (old_section_names + OLD_SECTION_H(n).sh_name, ".data") ||
789 !strcmp (old_section_names + OLD_SECTION_H(n).sh_name, ".data1") ||
790 (old_sdata_index && (n == old_sdata_index)))
791 src = (caddr_t) OLD_SECTION_H(n).sh_addr;
792 else
793 src = old_base + OLD_SECTION_H(n).sh_offset;
794
795 memcpy (NEW_SECTION_H(nn).sh_offset + new_base, src,
796 ((n == old_sdata_index) ?
797 old_sdata_size :
798 NEW_SECTION_H(nn).sh_size));
799
800 /* If it is the symbol table, its st_shndx field needs to be patched. */
801 if (NEW_SECTION_H(nn).sh_type == SHT_SYMTAB
802 || NEW_SECTION_H(nn).sh_type == SHT_DYNSYM)
803 {
804 Elf32_Shdr *spt = &NEW_SECTION_H(nn);
805 unsigned int num = spt->sh_size / spt->sh_entsize;
806 Elf32_Sym * sym = (Elf32_Sym *) (NEW_SECTION_H(nn).sh_offset +
807 new_base);
808 for (; num--; sym++)
809 {
810 if ((sym->st_shndx == SHN_UNDEF)
811 || (sym->st_shndx == SHN_ABS)
812 || (sym->st_shndx == SHN_COMMON))
813 continue;
814
815 PATCH_INDEX(sym->st_shndx);
816 }
817 }
818 }
819
820 /* Close the files and make the new file executable */
821
822 if (close (old_file))
823 fatal ("Can't close(%s): errno %d\n", old_name, errno);
824
825 if (close (new_file))
826 fatal ("Can't close(%s): errno %d\n", new_name, errno);
827
828 if (stat (new_name, &stat_buf) == -1)
829 fatal ("Can't stat(%s): errno %d\n", new_name, errno);
830
831 n = umask (777);
832 umask (n);
833 stat_buf.st_mode |= 0111 & ~n;
834 if (chmod (new_name, stat_buf.st_mode) == -1)
835 fatal ("Can't chmod(%s): errno %d\n", new_name, errno);
836}