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[bpt/emacs.git] / src / unexsni.c
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.
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2, or (at your option)
8 any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18
19 In other words, you are welcome to use, share and improve this program.
20 You are forbidden to forbid anyone else to use, share and improve
21 what you give them. Help stamp out software-hoarding! */
22
23
24 /*
25 * unexec.c - Convert a running program into an a.out file.
26 *
27 * Author: Spencer W. Thomas
28 * Computer Science Dept.
29 * University of Utah
30 * Date: Tue Mar 2 1982
31 * Modified heavily since then.
32 *
33 * Synopsis:
34 * unexec (new_name, a_name, data_start, bss_start, entry_address)
35 * char *new_name, *a_name;
36 * unsigned data_start, bss_start, entry_address;
37 *
38 * Takes a snapshot of the program and makes an a.out format file in the
39 * file named by the string argument new_name.
40 * If a_name is non-NULL, the symbol table will be taken from the given file.
41 * On some machines, an existing a_name file is required.
42 *
43 * The boundaries within the a.out file may be adjusted with the data_start
44 * and bss_start arguments. Either or both may be given as 0 for defaults.
45 *
46 * Data_start gives the boundary between the text segment and the data
47 * segment of the program. The text segment can contain shared, read-only
48 * program code and literal data, while the data segment is always unshared
49 * and unprotected. Data_start gives the lowest unprotected address.
50 * The value you specify may be rounded down to a suitable boundary
51 * as required by the machine you are using.
52 *
53 * Specifying zero for data_start means the boundary between text and data
54 * should not be the same as when the program was loaded.
55 * If NO_REMAP is defined, the argument data_start is ignored and the
56 * segment boundaries are never changed.
57 *
58 * Bss_start indicates how much of the data segment is to be saved in the
59 * a.out file and restored when the program is executed. It gives the lowest
60 * unsaved address, and is rounded up to a page boundary. The default when 0
61 * is given assumes that the entire data segment is to be stored, including
62 * the previous data and bss as well as any additional storage allocated with
63 * break (2).
64 *
65 * The new file is set up to start at entry_address.
66 *
67 * If you make improvements I'd like to get them too.
68 * harpo!utah-cs!thomas, thomas@Utah-20
69 *
70 */
71
72 /* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
73 * ELF support added.
74 *
75 * Basic theory: the data space of the running process needs to be
76 * dumped to the output file. Normally we would just enlarge the size
77 * of .data, scooting everything down. But we can't do that in ELF,
78 * because there is often something between the .data space and the
79 * .bss space.
80 *
81 * In the temacs dump below, notice that the Global Offset Table
82 * (.got) and the Dynamic link data (.dynamic) come between .data1 and
83 * .bss. It does not work to overlap .data with these fields.
84 *
85 * The solution is to create a new .data segment. This segment is
86 * filled with data from the current process. Since the contents of
87 * various sections refer to sections by index, the new .data segment
88 * is made the last in the table to avoid changing any existing index.
89 */
90
91 /* Modified by wtien@urbana.mcd.mot.com of Motorola Inc.
92 *
93 * The above mechanism does not work if the unexeced ELF file is being
94 * re-layout by other applications (such as `strip'). All the applications
95 * that re-layout the internal of ELF will layout all sections in ascending
96 * order of their file offsets. After the re-layout, the data2 section will
97 * still be the LAST section in the section header vector, but its file offset
98 * is now being pushed far away down, and causes part of it not to be mapped
99 * in (ie. not covered by the load segment entry in PHDR vector), therefore
100 * causes the new binary to fail.
101 *
102 * The solution is to modify the unexec algorithm to insert the new data2
103 * section header right before the new bss section header, so their file
104 * offsets will be in the ascending order. Since some of the section's (all
105 * sections AFTER the bss section) indexes are now changed, we also need to
106 * modify some fields to make them point to the right sections. This is done
107 * by macro PATCH_INDEX. All the fields that need to be patched are:
108 *
109 * 1. ELF header e_shstrndx field.
110 * 2. section header sh_link and sh_info field.
111 * 3. symbol table entry st_shndx field.
112 */
113
114 /*
115 * New modifications for Siemens Nixdorf's MIPS-based machines.
116 * Marco.Walther@mch.sni.de
117 *
118 * The problem: Before the bss segment we have a so called sbss segment
119 * (small bss) and maybe an sdata segment. These segments
120 * must also be handled correct.
121 *
122 * /home1/marco/emacs/emacs-19.22/src
123 * dump -hv temacs
124 *
125 * temacs:
126 *
127 * **** SECTION HEADER TABLE ****
128 * [No] Type Flags Addr Offset Size Name
129 * Link Info Adralgn Entsize
130 *
131 * [1] PBIT -A-- 0x4000f4 0xf4 0x13 .interp
132 * 0 0 0x1 0
133 *
134 * [2] REGI -A-- 0x400108 0x108 0x18 .reginfo
135 * 0 0 0x4 0x18
136 *
137 * [3] DYNM -A-- 0x400120 0x120 0xb8 .dynamic
138 * 6 0 0x4 0x8
139 *
140 * [4] HASH -A-- 0x4001d8 0x1d8 0x8a0 .hash
141 * 5 0 0x4 0x4
142 *
143 * [5] DYNS -A-- 0x400a78 0xa78 0x11f0 .dynsym
144 * 6 2 0x4 0x10
145 *
146 * [6] STRT -A-- 0x401c68 0x1c68 0xbf9 .dynstr
147 * 0 0 0x1 0
148 *
149 * [7] REL -A-- 0x402864 0x2864 0x18 .rel.dyn
150 * 5 14 0x4 0x8
151 *
152 * [8] PBIT -AI- 0x402880 0x2880 0x60 .init
153 * 0 0 0x10 0x1
154 *
155 * [9] PBIT -AI- 0x4028e0 0x28e0 0x1234 .plt
156 * 0 0 0x4 0x4
157 *
158 * [10] PBIT -AI- 0x403b20 0x3b20 0xee400 .text
159 * 0 0 0x20 0x1
160 *
161 * [11] PBIT -AI- 0x4f1f20 0xf1f20 0x60 .fini
162 * 0 0 0x10 0x1
163 *
164 * [12] PBIT -A-- 0x4f1f80 0xf1f80 0xd90 .rdata
165 * 0 0 0x10 0x1
166 *
167 * [13] PBIT -A-- 0x4f2d10 0xf2d10 0x17e0 .rodata
168 * 0 0 0x10 0x1
169 *
170 * [14] PBIT WA-- 0x5344f0 0xf44f0 0x4b3e4 .data <<<<<
171 * 0 0 0x10 0x1
172 *
173 * [15] PBIT WA-G 0x57f8d4 0x13f8d4 0x2a84 .got
174 * 0 0 0x4 0x4
175 *
176 * [16] PBIT WA-G 0x582360 0x142360 0x10 .sdata <<<<<
177 * 0 0 0x10 0x1
178 *
179 * [17] NOBI WA-G 0x582370 0x142370 0xb84 .sbss <<<<<
180 * 0 0 0x4 0
181 *
182 * [18] NOBI WA-- 0x582f00 0x142370 0x27ec0 .bss <<<<<
183 * 0 0 0x10 0x1
184 *
185 * [19] SYMT ---- 0 0x142370 0x10e40 .symtab
186 * 20 1108 0x4 0x10
187 *
188 * [20] STRT ---- 0 0x1531b0 0xed9e .strtab
189 * 0 0 0x1 0
190 *
191 * [21] STRT ---- 0 0x161f4e 0xb5 .shstrtab
192 * 0 0 0x1 0
193 *
194 * [22] PBIT ---- 0 0x162003 0x28e2a .comment
195 * 0 0 0x1 0x1
196 *
197 * [23] PBIT ---- 0 0x18ae2d 0x592 .debug
198 * 0 0 0x1 0
199 *
200 * [24] PBIT ---- 0 0x18b3bf 0x80 .line
201 * 0 0 0x1 0
202 *
203 * [25] MDBG ---- 0 0x18b440 0x60 .mdebug
204 * 0 0 0x4 0
205 *
206 *
207 * dump -hv emacs
208 *
209 * emacs:
210 *
211 * **** SECTION HEADER TABLE ****
212 * [No] Type Flags Addr Offset Size Name
213 * Link Info Adralgn Entsize
214 *
215 * [1] PBIT -A-- 0x4000f4 0xf4 0x13 .interp
216 * 0 0 0x1 0
217 *
218 * [2] REGI -A-- 0x400108 0x108 0x18 .reginfo
219 * 0 0 0x4 0x18
220 *
221 * [3] DYNM -A-- 0x400120 0x120 0xb8 .dynamic
222 * 6 0 0x4 0x8
223 *
224 * [4] HASH -A-- 0x4001d8 0x1d8 0x8a0 .hash
225 * 5 0 0x4 0x4
226 *
227 * [5] DYNS -A-- 0x400a78 0xa78 0x11f0 .dynsym
228 * 6 2 0x4 0x10
229 *
230 * [6] STRT -A-- 0x401c68 0x1c68 0xbf9 .dynstr
231 * 0 0 0x1 0
232 *
233 * [7] REL -A-- 0x402864 0x2864 0x18 .rel.dyn
234 * 5 14 0x4 0x8
235 *
236 * [8] PBIT -AI- 0x402880 0x2880 0x60 .init
237 * 0 0 0x10 0x1
238 *
239 * [9] PBIT -AI- 0x4028e0 0x28e0 0x1234 .plt
240 * 0 0 0x4 0x4
241 *
242 * [10] PBIT -AI- 0x403b20 0x3b20 0xee400 .text
243 * 0 0 0x20 0x1
244 *
245 * [11] PBIT -AI- 0x4f1f20 0xf1f20 0x60 .fini
246 * 0 0 0x10 0x1
247 *
248 * [12] PBIT -A-- 0x4f1f80 0xf1f80 0xd90 .rdata
249 * 0 0 0x10 0x1
250 *
251 * [13] PBIT -A-- 0x4f2d10 0xf2d10 0x17e0 .rodata
252 * 0 0 0x10 0x1
253 *
254 * [14] PBIT WA-- 0x5344f0 0xf44f0 0x4b3e4 .data <<<<<
255 * 0 0 0x10 0x1
256 *
257 * [15] PBIT WA-G 0x57f8d4 0x13f8d4 0x2a84 .got
258 * 0 0 0x4 0x4
259 *
260 * [16] PBIT WA-G 0x582360 0x142360 0xb94 .sdata <<<<<
261 * 0 0 0x10 0x1
262 *
263 * [17] PBIT WA-- 0x582f00 0x142f00 0x94100 .data <<<<<
264 * 0 0 0x10 0x1
265 *
266 * [18] NOBI WA-G 0x617000 0x1d7000 0 .sbss <<<<<
267 * 0 0 0x4 0
268 *
269 * [19] NOBI WA-- 0x617000 0x1d7000 0 .bss <<<<<
270 * 0 0 0x4 0x1
271 *
272 * [20] SYMT ---- 0 0x1d7000 0x10e40 .symtab
273 * 21 1109 0x4 0x10
274 *
275 * [21] STRT ---- 0 0x1e7e40 0xed9e .strtab
276 * 0 0 0x1 0
277 *
278 * [22] STRT ---- 0 0x1f6bde 0xb5 .shstrtab
279 * 0 0 0x1 0
280 *
281 * [23] PBIT ---- 0 0x1f6c93 0x28e2a .comment
282 * 0 0 0x1 0x1
283 *
284 * [24] PBIT ---- 0 0x21fabd 0x592 .debug
285 * 0 0 0x1 0
286 *
287 * [25] PBIT ---- 0 0x22004f 0x80 .line
288 * 0 0 0x1 0
289 *
290 * [26] MDBG ---- 0 0x2200d0 0x60 .mdebug
291 * 0 0 0x4 0
292 *
293 */
294 \f
295 #include <sys/types.h>
296 #include <stdio.h>
297 #include <sys/stat.h>
298 #include <memory.h>
299 #include <string.h>
300 #include <errno.h>
301 #include <unistd.h>
302 #include <fcntl.h>
303 #include <elf.h>
304 #include <sys/mman.h>
305
306 #ifndef emacs
307 #define fatal(a, b, c) fprintf(stderr, a, b, c), exit(1)
308 #else
309 extern void fatal(char *, ...);
310 #endif
311
312 /* Get the address of a particular section or program header entry,
313 * accounting for the size of the entries.
314 */
315
316 #define OLD_SECTION_H(n) \
317 (*(Elf32_Shdr *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
318 #define NEW_SECTION_H(n) \
319 (*(Elf32_Shdr *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
320 #define OLD_PROGRAM_H(n) \
321 (*(Elf32_Phdr *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
322 #define NEW_PROGRAM_H(n) \
323 (*(Elf32_Phdr *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
324
325 #define PATCH_INDEX(n) \
326 do { \
327 if ((n) >= old_sbss_index) \
328 (n) += 1 + (old_sdata_index ? 0 : 1); } while (0)
329
330 typedef unsigned char byte;
331
332 /* Round X up to a multiple of Y. */
333
334 int
335 round_up (x, y)
336 int x, y;
337 {
338 int rem = x % y;
339 if (rem == 0)
340 return x;
341 return x - rem + y;
342 }
343
344 /* ****************************************************************
345 * unexec
346 *
347 * driving logic.
348 *
349 * In ELF, this works by replacing the old .bss section with a new
350 * .data section, and inserting an empty .bss immediately afterwards.
351 *
352 */
353 void
354 unexec (new_name, old_name, data_start, bss_start, entry_address)
355 char *new_name, *old_name;
356 unsigned data_start, bss_start, entry_address;
357 {
358 extern unsigned int bss_end;
359 int new_file, old_file, new_file_size;
360
361 /* Pointers to the base of the image of the two files. */
362 caddr_t old_base, new_base;
363
364 /* Pointers to the file, program and section headers for the old and new
365 * files.
366 */
367 Elf32_Ehdr *old_file_h, *new_file_h;
368 Elf32_Phdr *old_program_h, *new_program_h;
369 Elf32_Shdr *old_section_h, *new_section_h;
370
371 /* Point to the section name table in the old file */
372 char *old_section_names;
373
374 Elf32_Addr old_bss_addr, new_bss_addr;
375 Elf32_Addr old_sbss_addr;
376 Elf32_Word old_bss_size, new_data2_size;
377 Elf32_Word old_sbss_size, new_data3_size;
378 Elf32_Off new_data2_offset;
379 Elf32_Off new_data3_offset;
380 Elf32_Addr new_data2_addr;
381 Elf32_Addr new_data3_addr;
382
383 Elf32_Word old_sdata_size, new_sdata_size;
384 int old_sdata_index = 0;
385
386 int n, nn, old_data_index, new_data2_align;
387 int old_bss_index;
388 int old_sbss_index;
389 int old_bss_padding;
390 struct stat stat_buf;
391
392 /* Open the old file & map it into the address space. */
393
394 old_file = open (old_name, O_RDONLY);
395
396 if (old_file < 0)
397 fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
398
399 if (fstat (old_file, &stat_buf) == -1)
400 fatal ("Can't fstat(%s): errno %d\n", old_name, errno);
401
402 old_base = mmap (0, stat_buf.st_size, PROT_READ, MAP_SHARED, old_file, 0);
403
404 if (old_base == (caddr_t) -1)
405 fatal ("Can't mmap(%s): errno %d\n", old_name, errno);
406
407 #ifdef DEBUG
408 fprintf (stderr, "mmap(%s, %x) -> %x\n", old_name, stat_buf.st_size,
409 old_base);
410 #endif
411
412 /* Get pointers to headers & section names */
413
414 old_file_h = (Elf32_Ehdr *) old_base;
415 old_program_h = (Elf32_Phdr *) ((byte *) old_base + old_file_h->e_phoff);
416 old_section_h = (Elf32_Shdr *) ((byte *) old_base + old_file_h->e_shoff);
417 old_section_names = (char *) old_base
418 + OLD_SECTION_H(old_file_h->e_shstrndx).sh_offset;
419
420 /* Find the old .sbss section.
421 */
422
423 for (old_sbss_index = 1; old_sbss_index < old_file_h->e_shnum;
424 old_sbss_index++)
425 {
426 #ifdef DEBUG
427 fprintf (stderr, "Looking for .sbss - found %s\n",
428 old_section_names + OLD_SECTION_H(old_sbss_index).sh_name);
429 #endif
430 if (!strcmp (old_section_names + OLD_SECTION_H(old_sbss_index).sh_name,
431 ".sbss"))
432 break;
433 }
434 if (old_sbss_index == old_file_h->e_shnum)
435 fatal ("Can't find .sbss in %s.\n", old_name, 0);
436
437 if (!strcmp(old_section_names + OLD_SECTION_H(old_sbss_index - 1).sh_name,
438 ".sdata"))
439 {
440 old_sdata_index = old_sbss_index - 1;
441 }
442
443
444 /* Find the old .bss section.
445 */
446
447 for (old_bss_index = 1; old_bss_index < old_file_h->e_shnum; old_bss_index++)
448 {
449 #ifdef DEBUG
450 fprintf (stderr, "Looking for .bss - found %s\n",
451 old_section_names + OLD_SECTION_H(old_bss_index).sh_name);
452 #endif
453 if (!strcmp (old_section_names + OLD_SECTION_H(old_bss_index).sh_name,
454 ".bss"))
455 break;
456 }
457 if (old_bss_index == old_file_h->e_shnum)
458 fatal ("Can't find .bss in %s.\n", old_name, 0);
459
460 if (old_sbss_index != (old_bss_index - 1))
461 fatal (".sbss should come immediatly before .bss in %s.\n", old_name, 0);
462
463 /* Figure out parameters of the new data3 and data2 sections.
464 * Change the sbss and bss sections.
465 */
466
467 old_bss_addr = OLD_SECTION_H(old_bss_index).sh_addr;
468 old_bss_size = OLD_SECTION_H(old_bss_index).sh_size;
469
470 old_sbss_addr = OLD_SECTION_H(old_sbss_index).sh_addr;
471 old_sbss_size = OLD_SECTION_H(old_sbss_index).sh_size;
472
473 if (old_sdata_index)
474 {
475 old_sdata_size = OLD_SECTION_H(old_sdata_index).sh_size;
476 }
477
478 #if defined(emacs) || !defined(DEBUG)
479 bss_end = (unsigned int) sbrk (0);
480 new_bss_addr = (Elf32_Addr) bss_end;
481 #else
482 new_bss_addr = old_bss_addr + old_bss_size + 0x1234;
483 #endif
484 if (old_sdata_index)
485 {
486 new_sdata_size = OLD_SECTION_H(old_sbss_index).sh_offset -
487 OLD_SECTION_H(old_sdata_index).sh_offset + old_sbss_size;
488 }
489
490 new_data3_addr = old_sbss_addr;
491 new_data3_size = old_sbss_size;
492 new_data3_offset = OLD_SECTION_H(old_sbss_index).sh_offset;
493
494 new_data2_addr = old_bss_addr;
495 new_data2_size = new_bss_addr - old_bss_addr;
496 new_data2_align = (new_data3_offset + old_sbss_size) %
497 OLD_SECTION_H(old_bss_index).sh_addralign;
498 new_data2_align = new_data2_align ?
499 OLD_SECTION_H(old_bss_index).sh_addralign - new_data2_align :
500 0;
501 new_data2_offset = new_data3_offset + old_sbss_size + new_data2_align;
502
503 old_bss_padding = OLD_SECTION_H(old_bss_index).sh_offset -
504 OLD_SECTION_H(old_sbss_index).sh_offset;
505 #ifdef DEBUG
506 fprintf (stderr, "old_bss_index %d\n", old_bss_index);
507 fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
508 fprintf (stderr, "old_bss_size %x\n", old_bss_size);
509 fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
510 fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
511 fprintf (stderr, "new_data2_size %x\n", new_data2_size);
512 fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
513 fprintf (stderr, "old_sbss_index %d\n", old_sbss_index);
514 fprintf (stderr, "old_sbss_addr %x\n", old_sbss_addr);
515 fprintf (stderr, "old_sbss_size %x\n", old_sbss_size);
516 if (old_sdata_index)
517 {
518 fprintf (stderr, "old_sdata_size %x\n", old_sdata_size);
519 fprintf (stderr, "new_sdata_size %x\n", new_sdata_size);
520 }
521 else
522 {
523 fprintf (stderr, "new_data3_addr %x\n", new_data3_addr);
524 fprintf (stderr, "new_data3_size %x\n", new_data3_size);
525 fprintf (stderr, "new_data3_offset %x\n", new_data3_offset);
526 }
527 #endif
528
529 if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
530 fatal (".bss shrank when undumping???\n", 0, 0);
531
532 /* Set the output file to the right size and mmap(2) it. Set
533 * pointers to various interesting objects. stat_buf still has
534 * old_file data.
535 */
536
537 new_file = open (new_name, O_RDWR | O_CREAT, 0666);
538 if (new_file < 0)
539 fatal ("Can't creat(%s): errno %d\n", new_name, errno);
540
541 new_file_size = stat_buf.st_size +
542 ((1 + (old_sdata_index ? 0 : 1)) * old_file_h->e_shentsize) +
543 new_data2_size + new_data3_size + new_data2_align;
544
545 if (ftruncate (new_file, new_file_size))
546 fatal ("Can't ftruncate(%s): errno %d\n", new_name, errno);
547
548 new_base = mmap (0, new_file_size, PROT_READ | PROT_WRITE, MAP_SHARED,
549 new_file, 0);
550
551 if (new_base == (caddr_t) -1)
552 fatal ("Can't mmap(%s): errno %d\n", new_name, errno);
553
554 new_file_h = (Elf32_Ehdr *) new_base;
555 new_program_h = (Elf32_Phdr *) ((byte *) new_base + old_file_h->e_phoff);
556 new_section_h = (Elf32_Shdr *) ((byte *) new_base +
557 old_file_h->e_shoff +
558 new_data2_size +
559 new_data2_align +
560 new_data3_size);
561
562 /* Make our new file, program and section headers as copies of the
563 * originals.
564 */
565
566 memcpy (new_file_h, old_file_h, old_file_h->e_ehsize);
567 memcpy (new_program_h, old_program_h,
568 old_file_h->e_phnum * old_file_h->e_phentsize);
569
570 /* Modify the e_shstrndx if necessary. */
571 PATCH_INDEX (new_file_h->e_shstrndx);
572
573 /* Fix up file header. We'll add one section. Section header is
574 * further away now.
575 */
576
577 new_file_h->e_shoff += new_data2_size + new_data2_align + new_data3_size;
578 new_file_h->e_shnum += 1 + (old_sdata_index ? 0 : 1);
579
580 #ifdef DEBUG
581 fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff);
582 fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum);
583 fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff);
584 fprintf (stderr, "New section count %d\n", new_file_h->e_shnum);
585 #endif
586
587 /* Fix up a new program header. Extend the writable data segment so
588 * that the bss area is covered too. Find that segment by looking
589 * for a segment that ends just before the .bss area. Make sure
590 * that no segments are above the new .data2. Put a loop at the end
591 * to adjust the offset and address of any segment that is above
592 * data2, just in case we decide to allow this later.
593 */
594
595 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
596 {
597 /* Compute maximum of all requirements for alignment of section. */
598 int alignment = (NEW_PROGRAM_H (n)).p_align;
599 if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment)
600 alignment = OLD_SECTION_H (old_bss_index).sh_addralign;
601
602 if ((OLD_SECTION_H (old_sbss_index)).sh_addralign > alignment)
603 alignment = OLD_SECTION_H (old_sbss_index).sh_addralign;
604
605 /* Supposedly this condition is okay for the SGI. */
606 #if 0
607 if (NEW_PROGRAM_H(n).p_vaddr + NEW_PROGRAM_H(n).p_filesz > old_bss_addr)
608 fatal ("Program segment above .bss in %s\n", old_name, 0);
609 #endif
610
611 if (NEW_PROGRAM_H(n).p_type == PT_LOAD
612 && (round_up ((NEW_PROGRAM_H (n)).p_vaddr
613 + (NEW_PROGRAM_H (n)).p_filesz,
614 alignment)
615 == round_up (old_bss_addr, alignment)))
616 break;
617 }
618 if (n < 0)
619 fatal ("Couldn't find segment next to .bss in %s\n", old_name, 0);
620
621 NEW_PROGRAM_H(n).p_filesz += new_data2_size + new_data2_align +
622 new_data3_size;
623 NEW_PROGRAM_H(n).p_memsz = NEW_PROGRAM_H(n).p_filesz;
624
625 #if 1 /* Maybe allow section after data2 - does this ever happen? */
626 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
627 {
628 if (NEW_PROGRAM_H(n).p_vaddr
629 && NEW_PROGRAM_H(n).p_vaddr >= new_data3_addr)
630 NEW_PROGRAM_H(n).p_vaddr += new_data2_size - old_bss_size +
631 new_data3_size - old_sbss_size;
632
633 if (NEW_PROGRAM_H(n).p_offset >= new_data3_offset)
634 NEW_PROGRAM_H(n).p_offset += new_data2_size + new_data2_align +
635 new_data3_size;
636 }
637 #endif
638
639 /* Fix up section headers based on new .data2 section. Any section
640 * whose offset or virtual address is after the new .data2 section
641 * gets its value adjusted. .bss size becomes zero and new address
642 * is set. data2 section header gets added by copying the existing
643 * .data header and modifying the offset, address and size.
644 */
645 for (old_data_index = 1; old_data_index < old_file_h->e_shnum;
646 old_data_index++)
647 if (!strcmp (old_section_names + OLD_SECTION_H(old_data_index).sh_name,
648 ".data"))
649 break;
650 if (old_data_index == old_file_h->e_shnum)
651 fatal ("Can't find .data in %s.\n", old_name, 0);
652
653 /* Walk through all section headers, insert the new data2 section right
654 before the new bss section. */
655 for (n = 1, nn = 1; n < old_file_h->e_shnum; n++, nn++)
656 {
657 caddr_t src;
658
659 if (n == old_sbss_index)
660
661 /* If it is sbss section, insert the new data3 section before it. */
662 {
663 /* Steal the data section header for this data3 section. */
664 if (!old_sdata_index)
665 {
666 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(old_data_index),
667 new_file_h->e_shentsize);
668
669 NEW_SECTION_H(nn).sh_addr = new_data3_addr;
670 NEW_SECTION_H(nn).sh_offset = new_data3_offset;
671 NEW_SECTION_H(nn).sh_size = new_data3_size;
672 NEW_SECTION_H(nn).sh_flags = OLD_SECTION_H(n).sh_flags;
673 /* Use the sbss section's alignment. This will assure that the
674 new data3 section always be placed in the same spot as the old
675 sbss section by any other application. */
676 NEW_SECTION_H(nn).sh_addralign = OLD_SECTION_H(n).sh_addralign;
677
678 /* Now copy over what we have in the memory now. */
679 memcpy (NEW_SECTION_H(nn).sh_offset + new_base,
680 (caddr_t) OLD_SECTION_H(n).sh_addr,
681 new_data3_size);
682 /* the new .data2 section should also come before the
683 * new .sbss section */
684 nn += 2;
685 }
686 else
687 {
688 /* We always have a .sdata section: append the contents of the
689 * old .sbss section.
690 */
691 memcpy (new_data3_offset + new_base,
692 (caddr_t) OLD_SECTION_H(n).sh_addr,
693 new_data3_size);
694 nn ++;
695 }
696 }
697 else if (n == old_bss_index)
698
699 /* If it is bss section, insert the new data2 section before it. */
700 {
701 Elf32_Word tmp_align;
702 Elf32_Addr tmp_addr;
703
704 tmp_align = OLD_SECTION_H(n).sh_addralign;
705 tmp_addr = OLD_SECTION_H(n).sh_addr;
706
707 nn -= 2;
708 /* Steal the data section header for this data2 section. */
709 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(old_data_index),
710 new_file_h->e_shentsize);
711
712 NEW_SECTION_H(nn).sh_addr = new_data2_addr;
713 NEW_SECTION_H(nn).sh_offset = new_data2_offset;
714 NEW_SECTION_H(nn).sh_size = new_data2_size;
715 /* Use the bss section's alignment. This will assure that the
716 new data2 section always be placed in the same spot as the old
717 bss section by any other application. */
718 NEW_SECTION_H(nn).sh_addralign = tmp_align;
719
720 /* Now copy over what we have in the memory now. */
721 memcpy (NEW_SECTION_H(nn).sh_offset + new_base,
722 (caddr_t) tmp_addr, new_data2_size);
723 nn += 2;
724 }
725
726 memcpy (&NEW_SECTION_H(nn), &OLD_SECTION_H(n),
727 old_file_h->e_shentsize);
728
729 if (old_sdata_index && n == old_sdata_index)
730 /* The old .sdata section has now a new size */
731 NEW_SECTION_H(nn).sh_size = new_sdata_size;
732
733 /* The new bss section's size is zero, and its file offset and virtual
734 address should be off by NEW_DATA2_SIZE. */
735 if (n == old_sbss_index)
736 {
737 /* NN should be `old_sbss_index + 2' at this point. */
738 NEW_SECTION_H(nn).sh_offset += new_data2_size + new_data2_align +
739 new_data3_size;
740 NEW_SECTION_H(nn).sh_addr += new_data2_size + new_data2_align +
741 new_data3_size;
742 /* Let the new bss section address alignment be the same as the
743 section address alignment followed the old bss section, so
744 this section will be placed in exactly the same place. */
745 NEW_SECTION_H(nn).sh_addralign =
746 OLD_SECTION_H(nn + (old_sdata_index ? 1 : 0)).sh_addralign;
747 NEW_SECTION_H(nn).sh_size = 0;
748 }
749 else if (n == old_bss_index)
750 {
751 /* NN should be `old_bss_index + 2' at this point. */
752 NEW_SECTION_H(nn).sh_offset += new_data2_size + new_data2_align +
753 new_data3_size - old_bss_padding;
754 NEW_SECTION_H(nn).sh_addr += new_data2_size;
755 /* Let the new bss section address alignment be the same as the
756 section address alignment followed the old bss section, so
757 this section will be placed in exactly the same place. */
758 NEW_SECTION_H(nn).sh_addralign =
759 OLD_SECTION_H((nn - (old_sdata_index ? 0 : 1))).sh_addralign;
760 NEW_SECTION_H(nn).sh_size = 0;
761 }
762 /* Any section that was original placed AFTER the bss section should now
763 be off by NEW_DATA2_SIZE. */
764 else if (NEW_SECTION_H(nn).sh_offset >= new_data3_offset)
765 NEW_SECTION_H(nn).sh_offset += new_data2_size +
766 new_data2_align +
767 new_data3_size -
768 old_bss_padding;
769
770 /* If any section hdr refers to the section after the new .data
771 section, make it refer to next one because we have inserted
772 a new section in between. */
773
774 PATCH_INDEX(NEW_SECTION_H(nn).sh_link);
775 PATCH_INDEX(NEW_SECTION_H(nn).sh_info);
776
777 /* Now, start to copy the content of sections. */
778 if (NEW_SECTION_H(nn).sh_type == SHT_NULL
779 || NEW_SECTION_H(nn).sh_type == SHT_NOBITS)
780 continue;
781
782 /* Write out the sections. .data, .data1 and .sdata get copied from
783 * the current process instead of the old file.
784 */
785 if (!strcmp (old_section_names + OLD_SECTION_H(n).sh_name, ".data") ||
786 !strcmp (old_section_names + OLD_SECTION_H(n).sh_name, ".data1") ||
787 (old_sdata_index && (n == old_sdata_index)))
788 src = (caddr_t) OLD_SECTION_H(n).sh_addr;
789 else
790 src = old_base + OLD_SECTION_H(n).sh_offset;
791
792 memcpy (NEW_SECTION_H(nn).sh_offset + new_base, src,
793 ((n == old_sdata_index) ?
794 old_sdata_size :
795 NEW_SECTION_H(nn).sh_size));
796
797 /* If it is the symbol table, its st_shndx field needs to be patched. */
798 if (NEW_SECTION_H(nn).sh_type == SHT_SYMTAB
799 || NEW_SECTION_H(nn).sh_type == SHT_DYNSYM)
800 {
801 Elf32_Shdr *spt = &NEW_SECTION_H(nn);
802 unsigned int num = spt->sh_size / spt->sh_entsize;
803 Elf32_Sym * sym = (Elf32_Sym *) (NEW_SECTION_H(nn).sh_offset +
804 new_base);
805 for (; num--; sym++)
806 {
807 if ((sym->st_shndx == SHN_UNDEF)
808 || (sym->st_shndx == SHN_ABS)
809 || (sym->st_shndx == SHN_COMMON))
810 continue;
811
812 PATCH_INDEX(sym->st_shndx);
813 }
814 }
815 }
816
817 /* Close the files and make the new file executable */
818
819 if (close (old_file))
820 fatal ("Can't close(%s): errno %d\n", old_name, errno);
821
822 if (close (new_file))
823 fatal ("Can't close(%s): errno %d\n", new_name, errno);
824
825 if (stat (new_name, &stat_buf) == -1)
826 fatal ("Can't stat(%s): errno %d\n", new_name, errno);
827
828 n = umask (777);
829 umask (n);
830 stat_buf.st_mode |= 0111 & ~n;
831 if (chmod (new_name, stat_buf.st_mode) == -1)
832 fatal ("Can't chmod(%s): errno %d\n", new_name, errno);
833 }