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[__NetBSD__]: Add some conditionals for NetBSD.
[gnu-emacs] / src / unexelf.c
1 /* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992
2 Free Software Foundation, Inc.
3
4 This file is part of GNU Emacs.
5
6 GNU Emacs is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
9 any later version.
10
11 GNU Emacs is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GNU Emacs; see the file COPYING. If not, write to
18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA.
20
21 In other words, you are welcome to use, share and improve this program.
22 You are forbidden to forbid anyone else to use, share and improve
23 what you give them. Help stamp out software-hoarding! */
24
25
26 /*
27 * unexec.c - Convert a running program into an a.out file.
28 *
29 * Author: Spencer W. Thomas
30 * Computer Science Dept.
31 * University of Utah
32 * Date: Tue Mar 2 1982
33 * Modified heavily since then.
34 *
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;
39 *
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.
44 *
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.
47 *
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.
54 *
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.
59 *
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).
66 *
67 * The new file is set up to start at entry_address.
68 *
69 * If you make improvements I'd like to get them too.
70 * harpo!utah-cs!thomas, thomas@Utah-20
71 *
72 */
73
74 /* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
75 * ELF support added.
76 *
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.
82 *
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.
86 *
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.
91
92 * This is an example of how the section headers are changed. "Addr"
93 * is a process virtual address. "Offset" is a file offset.
94
95 raid:/nfs/raid/src/dist-18.56/src> dump -h temacs
96
97 temacs:
98
99 **** SECTION HEADER TABLE ****
100 [No] Type Flags Addr Offset Size Name
101 Link Info Adralgn Entsize
102
103 [1] 1 2 0x80480d4 0xd4 0x13 .interp
104 0 0 0x1 0
105
106 [2] 5 2 0x80480e8 0xe8 0x388 .hash
107 3 0 0x4 0x4
108
109 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
110 4 1 0x4 0x10
111
112 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
113 0 0 0x1 0
114
115 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
116 3 7 0x4 0x8
117
118 [6] 1 6 0x8049348 0x1348 0x3 .init
119 0 0 0x4 0
120
121 [7] 1 6 0x804934c 0x134c 0x680 .plt
122 0 0 0x4 0x4
123
124 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
125 0 0 0x4 0
126
127 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
128 0 0 0x4 0
129
130 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
131 0 0 0x4 0
132
133 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
134 0 0 0x4 0
135
136 [12] 1 3 0x8088330 0x3f330 0x20afc .data
137 0 0 0x4 0
138
139 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
140 0 0 0x4 0
141
142 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
143 0 0 0x4 0x4
144
145 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
146 4 0 0x4 0x8
147
148 [16] 8 3 0x80a98f4 0x608f4 0x449c .bss
149 0 0 0x4 0
150
151 [17] 2 0 0 0x608f4 0x9b90 .symtab
152 18 371 0x4 0x10
153
154 [18] 3 0 0 0x6a484 0x8526 .strtab
155 0 0 0x1 0
156
157 [19] 3 0 0 0x729aa 0x93 .shstrtab
158 0 0 0x1 0
159
160 [20] 1 0 0 0x72a3d 0x68b7 .comment
161 0 0 0x1 0
162
163 raid:/nfs/raid/src/dist-18.56/src> dump -h xemacs
164
165 xemacs:
166
167 **** SECTION HEADER TABLE ****
168 [No] Type Flags Addr Offset Size Name
169 Link Info Adralgn Entsize
170
171 [1] 1 2 0x80480d4 0xd4 0x13 .interp
172 0 0 0x1 0
173
174 [2] 5 2 0x80480e8 0xe8 0x388 .hash
175 3 0 0x4 0x4
176
177 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
178 4 1 0x4 0x10
179
180 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
181 0 0 0x1 0
182
183 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
184 3 7 0x4 0x8
185
186 [6] 1 6 0x8049348 0x1348 0x3 .init
187 0 0 0x4 0
188
189 [7] 1 6 0x804934c 0x134c 0x680 .plt
190 0 0 0x4 0x4
191
192 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
193 0 0 0x4 0
194
195 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
196 0 0 0x4 0
197
198 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
199 0 0 0x4 0
200
201 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
202 0 0 0x4 0
203
204 [12] 1 3 0x8088330 0x3f330 0x20afc .data
205 0 0 0x4 0
206
207 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
208 0 0 0x4 0
209
210 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
211 0 0 0x4 0x4
212
213 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
214 4 0 0x4 0x8
215
216 [16] 8 3 0x80c6800 0x7d800 0 .bss
217 0 0 0x4 0
218
219 [17] 2 0 0 0x7d800 0x9b90 .symtab
220 18 371 0x4 0x10
221
222 [18] 3 0 0 0x87390 0x8526 .strtab
223 0 0 0x1 0
224
225 [19] 3 0 0 0x8f8b6 0x93 .shstrtab
226 0 0 0x1 0
227
228 [20] 1 0 0 0x8f949 0x68b7 .comment
229 0 0 0x1 0
230
231 [21] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
232 0 0 0x4 0
233
234 * This is an example of how the file header is changed. "Shoff" is
235 * the section header offset within the file. Since that table is
236 * after the new .data section, it is moved. "Shnum" is the number of
237 * sections, which we increment.
238 *
239 * "Phoff" is the file offset to the program header. "Phentsize" and
240 * "Shentsz" are the program and section header entries sizes respectively.
241 * These can be larger than the apparent struct sizes.
242
243 raid:/nfs/raid/src/dist-18.56/src> dump -f temacs
244
245 temacs:
246
247 **** ELF HEADER ****
248 Class Data Type Machine Version
249 Entry Phoff Shoff Flags Ehsize
250 Phentsize Phnum Shentsz Shnum Shstrndx
251
252 1 1 2 3 1
253 0x80499cc 0x34 0x792f4 0 0x34
254 0x20 5 0x28 21 19
255
256 raid:/nfs/raid/src/dist-18.56/src> dump -f xemacs
257
258 xemacs:
259
260 **** ELF HEADER ****
261 Class Data Type Machine Version
262 Entry Phoff Shoff Flags Ehsize
263 Phentsize Phnum Shentsz Shnum Shstrndx
264
265 1 1 2 3 1
266 0x80499cc 0x34 0x96200 0 0x34
267 0x20 5 0x28 22 19
268
269 * These are the program headers. "Offset" is the file offset to the
270 * segment. "Vaddr" is the memory load address. "Filesz" is the
271 * segment size as it appears in the file, and "Memsz" is the size in
272 * memory. Below, the third segment is the code and the fourth is the
273 * data: the difference between Filesz and Memsz is .bss
274
275 raid:/nfs/raid/src/dist-18.56/src> dump -o temacs
276
277 temacs:
278 ***** PROGRAM EXECUTION HEADER *****
279 Type Offset Vaddr Paddr
280 Filesz Memsz Flags Align
281
282 6 0x34 0x8048034 0
283 0xa0 0xa0 5 0
284
285 3 0xd4 0 0
286 0x13 0 4 0
287
288 1 0x34 0x8048034 0
289 0x3f2f9 0x3f2f9 5 0x1000
290
291 1 0x3f330 0x8088330 0
292 0x215c4 0x25a60 7 0x1000
293
294 2 0x60874 0x80a9874 0
295 0x80 0 7 0
296
297 raid:/nfs/raid/src/dist-18.56/src> dump -o xemacs
298
299 xemacs:
300 ***** PROGRAM EXECUTION HEADER *****
301 Type Offset Vaddr Paddr
302 Filesz Memsz Flags Align
303
304 6 0x34 0x8048034 0
305 0xa0 0xa0 5 0
306
307 3 0xd4 0 0
308 0x13 0 4 0
309
310 1 0x34 0x8048034 0
311 0x3f2f9 0x3f2f9 5 0x1000
312
313 1 0x3f330 0x8088330 0
314 0x3e4d0 0x3e4d0 7 0x1000
315
316 2 0x60874 0x80a9874 0
317 0x80 0 7 0
318
319
320 */
321 \f
322 /* Modified by wtien@urbana.mcd.mot.com of Motorola Inc.
323 *
324 * The above mechanism does not work if the unexeced ELF file is being
325 * re-layout by other applications (such as `strip'). All the applications
326 * that re-layout the internal of ELF will layout all sections in ascending
327 * order of their file offsets. After the re-layout, the data2 section will
328 * still be the LAST section in the section header vector, but its file offset
329 * is now being pushed far away down, and causes part of it not to be mapped
330 * in (ie. not covered by the load segment entry in PHDR vector), therefore
331 * causes the new binary to fail.
332 *
333 * The solution is to modify the unexec algorithm to insert the new data2
334 * section header right before the new bss section header, so their file
335 * offsets will be in the ascending order. Since some of the section's (all
336 * sections AFTER the bss section) indexes are now changed, we also need to
337 * modify some fields to make them point to the right sections. This is done
338 * by macro PATCH_INDEX. All the fields that need to be patched are:
339 *
340 * 1. ELF header e_shstrndx field.
341 * 2. section header sh_link and sh_info field.
342 * 3. symbol table entry st_shndx field.
343 *
344 * The above example now should look like:
345
346 **** SECTION HEADER TABLE ****
347 [No] Type Flags Addr Offset Size Name
348 Link Info Adralgn Entsize
349
350 [1] 1 2 0x80480d4 0xd4 0x13 .interp
351 0 0 0x1 0
352
353 [2] 5 2 0x80480e8 0xe8 0x388 .hash
354 3 0 0x4 0x4
355
356 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
357 4 1 0x4 0x10
358
359 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
360 0 0 0x1 0
361
362 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
363 3 7 0x4 0x8
364
365 [6] 1 6 0x8049348 0x1348 0x3 .init
366 0 0 0x4 0
367
368 [7] 1 6 0x804934c 0x134c 0x680 .plt
369 0 0 0x4 0x4
370
371 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
372 0 0 0x4 0
373
374 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
375 0 0 0x4 0
376
377 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
378 0 0 0x4 0
379
380 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
381 0 0 0x4 0
382
383 [12] 1 3 0x8088330 0x3f330 0x20afc .data
384 0 0 0x4 0
385
386 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
387 0 0 0x4 0
388
389 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
390 0 0 0x4 0x4
391
392 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
393 4 0 0x4 0x8
394
395 [16] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
396 0 0 0x4 0
397
398 [17] 8 3 0x80c6800 0x7d800 0 .bss
399 0 0 0x4 0
400
401 [18] 2 0 0 0x7d800 0x9b90 .symtab
402 19 371 0x4 0x10
403
404 [19] 3 0 0 0x87390 0x8526 .strtab
405 0 0 0x1 0
406
407 [20] 3 0 0 0x8f8b6 0x93 .shstrtab
408 0 0 0x1 0
409
410 [21] 1 0 0 0x8f949 0x68b7 .comment
411 0 0 0x1 0
412
413 */
414 \f
415 #include <sys/types.h>
416 #include <stdio.h>
417 #include <sys/stat.h>
418 #include <memory.h>
419 #include <string.h>
420 #include <errno.h>
421 #include <unistd.h>
422 #include <fcntl.h>
423 #ifndef __NetBSD__
424 #include <elf.h>
425 #endif
426 #include <sys/mman.h>
427 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
428 #include <sys/elf_mips.h>
429 #include <sym.h>
430 #endif /* __sony_news && _SYSTYPE_SYSV */
431
432 #if defined (__alpha__) && !defined (__NetBSD__)
433 #include <sym.h> /* get COFF debugging symbol table declaration */
434 #endif
435
436 #ifdef __NetBSD__
437 /*
438 * NetBSD does not have normal-looking user-land ELF support.
439 */
440 # ifdef __alpha__
441 # define ELFSIZE 64
442 # else
443 # define ELFSIZE 32
444 # endif
445 # include <sys/exec_elf.h>
446
447 # define PT_LOAD Elf_pt_load
448 # define SHT_SYMTAB Elf_sht_symtab
449 # define SHT_DYNSYM Elf_sht_dynsym
450 # define SHT_NULL Elf_sht_null
451 # define SHT_NOBITS Elf_sht_nobits
452 # define SHT_REL Elf_sht_rel
453 # define SHT_RELA Elf_sht_rela
454
455 # define SHN_UNDEF Elf_eshn_undefined
456 # define SHN_ABS Elf_eshn_absolute
457 # define SHN_COMMON Elf_eshn_common
458
459 /*
460 * The magic of picking the right size types is handled by the ELFSIZE
461 * definition above.
462 */
463 # ifdef __STDC__
464 # define ElfW(type) Elf_##type
465 # else
466 # define ElfW(type) Elf_/**/type
467 # endif
468
469 # ifdef __alpha__
470 # include <sys/exec_ecoff.h>
471 # define HDRR struct ecoff_symhdr
472 # define pHDRR HDRR *
473 # endif
474 #endif /* __NetBSD__ */
475
476 #if __GNU_LIBRARY__ - 0 >= 6
477 # include <link.h> /* get ElfW etc */
478 #endif
479
480 #ifndef ElfW
481 # ifdef __STDC__
482 # define ElfW(type) Elf32_##type
483 # else
484 # define ElfW(type) Elf32_/**/type
485 # endif
486 #endif
487
488 #ifndef emacs
489 #define fatal(a, b, c) fprintf (stderr, a, b, c), exit (1)
490 #else
491 #include <config.h>
492 extern void fatal (char *, ...);
493 #endif
494
495 #ifndef ELF_BSS_SECTION_NAME
496 #define ELF_BSS_SECTION_NAME ".bss"
497 #endif
498
499 /* Get the address of a particular section or program header entry,
500 * accounting for the size of the entries.
501 */
502 /*
503 On PPC Reference Platform running Solaris 2.5.1
504 the plt section is also of type NOBI like the bss section.
505 (not really stored) and therefore sections after the bss
506 section start at the plt offset. The plt section is always
507 the one just before the bss section.
508 Thus, we modify the test from
509 if (NEW_SECTION_H (nn).sh_offset >= new_data2_offset)
510 to
511 if (NEW_SECTION_H (nn).sh_offset >=
512 OLD_SECTION_H (old_bss_index-1).sh_offset)
513 This is just a hack. We should put the new data section
514 before the .plt section.
515 And we should not have this routine at all but use
516 the libelf library to read the old file and create the new
517 file.
518 The changed code is minimal and depends on prep set in m/prep.h
519 Erik Deumens
520 Quantum Theory Project
521 University of Florida
522 deumens@qtp.ufl.edu
523 Apr 23, 1996
524 */
525
526 #define OLD_SECTION_H(n) \
527 (*(ElfW(Shdr) *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
528 #define NEW_SECTION_H(n) \
529 (*(ElfW(Shdr) *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
530 #define OLD_PROGRAM_H(n) \
531 (*(ElfW(Phdr) *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
532 #define NEW_PROGRAM_H(n) \
533 (*(ElfW(Phdr) *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
534
535 #define PATCH_INDEX(n) \
536 do { \
537 if ((int) (n) >= old_bss_index) \
538 (n)++; } while (0)
539 typedef unsigned char byte;
540
541 /* Round X up to a multiple of Y. */
542
543 int
544 round_up (x, y)
545 int x, y;
546 {
547 int rem = x % y;
548 if (rem == 0)
549 return x;
550 return x - rem + y;
551 }
552
553 /* ****************************************************************
554 * unexec
555 *
556 * driving logic.
557 *
558 * In ELF, this works by replacing the old .bss section with a new
559 * .data section, and inserting an empty .bss immediately afterwards.
560 *
561 */
562 void
563 unexec (new_name, old_name, data_start, bss_start, entry_address)
564 char *new_name, *old_name;
565 unsigned data_start, bss_start, entry_address;
566 {
567 int new_file, old_file, new_file_size;
568
569 /* Pointers to the base of the image of the two files. */
570 caddr_t old_base, new_base;
571
572 /* Pointers to the file, program and section headers for the old and new
573 * files.
574 */
575 ElfW(Ehdr) *old_file_h, *new_file_h;
576 ElfW(Phdr) *old_program_h, *new_program_h;
577 ElfW(Shdr) *old_section_h, *new_section_h;
578
579 /* Point to the section name table in the old file */
580 char *old_section_names;
581
582 ElfW(Addr) old_bss_addr, new_bss_addr;
583 ElfW(Word) old_bss_size, new_data2_size;
584 ElfW(Off) new_data2_offset;
585 ElfW(Addr) new_data2_addr;
586
587 int n, nn, old_bss_index, old_data_index, new_data2_index;
588 #if defined ( __sony_news) && defined (_SYSTYPE_SYSV)
589 int old_sbss_index, old_mdebug_index;
590 #endif /* __sony_news && _SYSTYPE_SYSV */
591 struct stat stat_buf;
592
593 /* Open the old file & map it into the address space. */
594
595 old_file = open (old_name, O_RDONLY);
596
597 if (old_file < 0)
598 fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
599
600 if (fstat (old_file, &stat_buf) == -1)
601 fatal ("Can't fstat (%s): errno %d\n", old_name, errno);
602
603 old_base = mmap (0, stat_buf.st_size, PROT_READ, MAP_SHARED, old_file, 0);
604
605 if (old_base == (caddr_t) -1)
606 fatal ("Can't mmap (%s): errno %d\n", old_name, errno);
607
608 #ifdef DEBUG
609 fprintf (stderr, "mmap (%s, %x) -> %x\n", old_name, stat_buf.st_size,
610 old_base);
611 #endif
612
613 /* Get pointers to headers & section names */
614
615 old_file_h = (ElfW(Ehdr) *) old_base;
616 old_program_h = (ElfW(Phdr) *) ((byte *) old_base + old_file_h->e_phoff);
617 old_section_h = (ElfW(Shdr) *) ((byte *) old_base + old_file_h->e_shoff);
618 old_section_names = (char *) old_base
619 + OLD_SECTION_H (old_file_h->e_shstrndx).sh_offset;
620
621 /* Find the old .bss section. Figure out parameters of the new
622 * data2 and bss sections.
623 */
624
625 for (old_bss_index = 1; old_bss_index < (int) old_file_h->e_shnum;
626 old_bss_index++)
627 {
628 #ifdef DEBUG
629 fprintf (stderr, "Looking for .bss - found %s\n",
630 old_section_names + OLD_SECTION_H (old_bss_index).sh_name);
631 #endif
632 if (!strcmp (old_section_names + OLD_SECTION_H (old_bss_index).sh_name,
633 ELF_BSS_SECTION_NAME))
634 break;
635 }
636 if (old_bss_index == old_file_h->e_shnum)
637 fatal ("Can't find .bss in %s.\n", old_name, 0);
638
639 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
640 for (old_sbss_index = 1; old_sbss_index < (int) old_file_h->e_shnum;
641 old_sbss_index++)
642 {
643 #ifdef DEBUG
644 fprintf (stderr, "Looking for .sbss - found %s\n",
645 old_section_names + OLD_SECTION_H (old_sbss_index).sh_name);
646 #endif
647 if (!strcmp (old_section_names + OLD_SECTION_H (old_sbss_index).sh_name,
648 ".sbss"))
649 break;
650 }
651 if (old_sbss_index == old_file_h->e_shnum)
652 {
653 old_bss_addr = OLD_SECTION_H(old_bss_index).sh_addr;
654 old_bss_size = OLD_SECTION_H(old_bss_index).sh_size;
655 new_data2_offset = OLD_SECTION_H(old_bss_index).sh_offset;
656 new_data2_index = old_bss_index;
657 }
658 else
659 {
660 old_bss_addr = OLD_SECTION_H(old_sbss_index).sh_addr;
661 old_bss_size = OLD_SECTION_H(old_bss_index).sh_size
662 + OLD_SECTION_H(old_sbss_index).sh_size;
663 new_data2_offset = OLD_SECTION_H(old_sbss_index).sh_offset;
664 new_data2_index = old_sbss_index;
665 }
666
667 for (old_mdebug_index = 1; old_mdebug_index < (int) old_file_h->e_shnum;
668 old_mdebug_index++)
669 {
670 #ifdef DEBUG
671 fprintf (stderr, "Looking for .mdebug - found %s\n",
672 old_section_names + OLD_SECTION_H (old_mdebug_index).sh_name);
673 #endif
674 if (!strcmp (old_section_names + OLD_SECTION_H (old_mdebug_index).sh_name,
675 ".mdebug"))
676 break;
677 }
678 if (old_mdebug_index == old_file_h->e_shnum)
679 old_mdebug_index = 0;
680 #else /* not (__sony_news && _SYSTYPE_SYSV) */
681 old_bss_addr = OLD_SECTION_H (old_bss_index).sh_addr;
682 old_bss_size = OLD_SECTION_H (old_bss_index).sh_size;
683 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
684 #if defined(emacs) || !defined(DEBUG)
685 new_bss_addr = (ElfW(Addr)) sbrk (0);
686 #else
687 new_bss_addr = old_bss_addr + old_bss_size + 0x1234;
688 #endif
689 new_data2_addr = old_bss_addr;
690 new_data2_size = new_bss_addr - old_bss_addr;
691 #if !defined (__sony_news) || !defined (_SYSTYPE_SYSV)
692 new_data2_offset = OLD_SECTION_H (old_bss_index).sh_offset;
693 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
694
695 #ifdef DEBUG
696 fprintf (stderr, "old_bss_index %d\n", old_bss_index);
697 fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
698 fprintf (stderr, "old_bss_size %x\n", old_bss_size);
699 fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
700 fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
701 fprintf (stderr, "new_data2_size %x\n", new_data2_size);
702 fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
703 #endif
704
705 if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
706 fatal (".bss shrank when undumping???\n", 0, 0);
707
708 /* Set the output file to the right size and mmap it. Set
709 * pointers to various interesting objects. stat_buf still has
710 * old_file data.
711 */
712
713 new_file = open (new_name, O_RDWR | O_CREAT, 0666);
714 if (new_file < 0)
715 fatal ("Can't creat (%s): errno %d\n", new_name, errno);
716
717 new_file_size = stat_buf.st_size + old_file_h->e_shentsize + new_data2_size;
718
719 if (ftruncate (new_file, new_file_size))
720 fatal ("Can't ftruncate (%s): errno %d\n", new_name, errno);
721
722 #ifdef UNEXEC_USE_MAP_PRIVATE
723 new_base = mmap (0, new_file_size, PROT_READ | PROT_WRITE, MAP_PRIVATE,
724 new_file, 0);
725 #else
726 new_base = mmap (0, new_file_size, PROT_READ | PROT_WRITE, MAP_SHARED,
727 new_file, 0);
728 #endif
729
730 if (new_base == (caddr_t) -1)
731 fatal ("Can't mmap (%s): errno %d\n", new_name, errno);
732
733 new_file_h = (ElfW(Ehdr) *) new_base;
734 new_program_h = (ElfW(Phdr) *) ((byte *) new_base + old_file_h->e_phoff);
735 new_section_h = (ElfW(Shdr) *)
736 ((byte *) new_base + old_file_h->e_shoff + new_data2_size);
737
738 /* Make our new file, program and section headers as copies of the
739 * originals.
740 */
741
742 memcpy (new_file_h, old_file_h, old_file_h->e_ehsize);
743 memcpy (new_program_h, old_program_h,
744 old_file_h->e_phnum * old_file_h->e_phentsize);
745
746 /* Modify the e_shstrndx if necessary. */
747 PATCH_INDEX (new_file_h->e_shstrndx);
748
749 /* Fix up file header. We'll add one section. Section header is
750 * further away now.
751 */
752
753 new_file_h->e_shoff += new_data2_size;
754 new_file_h->e_shnum += 1;
755
756 #ifdef DEBUG
757 fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff);
758 fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum);
759 fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff);
760 fprintf (stderr, "New section count %d\n", new_file_h->e_shnum);
761 #endif
762
763 /* Fix up a new program header. Extend the writable data segment so
764 * that the bss area is covered too. Find that segment by looking
765 * for a segment that ends just before the .bss area. Make sure
766 * that no segments are above the new .data2. Put a loop at the end
767 * to adjust the offset and address of any segment that is above
768 * data2, just in case we decide to allow this later.
769 */
770
771 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
772 {
773 /* Compute maximum of all requirements for alignment of section. */
774 int alignment = (NEW_PROGRAM_H (n)).p_align;
775 if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment)
776 alignment = OLD_SECTION_H (old_bss_index).sh_addralign;
777
778 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
779 if (NEW_PROGRAM_H (n).p_vaddr + NEW_PROGRAM_H (n).p_filesz
780 > round_up (old_bss_addr, alignment))
781 fatal ("Program segment above .bss in %s\n", old_name, 0);
782 #else /* not (__sony_news && _SYSTYPE_SYSV) */
783 if (NEW_PROGRAM_H (n).p_vaddr + NEW_PROGRAM_H (n).p_filesz > old_bss_addr)
784 fatal ("Program segment above .bss in %s\n", old_name, 0);
785 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
786
787 if (NEW_PROGRAM_H (n).p_type == PT_LOAD
788 && (round_up ((NEW_PROGRAM_H (n)).p_vaddr
789 + (NEW_PROGRAM_H (n)).p_filesz,
790 alignment)
791 == round_up (old_bss_addr, alignment)))
792 break;
793 }
794 if (n < 0)
795 fatal ("Couldn't find segment next to .bss in %s\n", old_name, 0);
796
797 NEW_PROGRAM_H (n).p_filesz += new_data2_size;
798 NEW_PROGRAM_H (n).p_memsz = NEW_PROGRAM_H (n).p_filesz;
799
800 #if 0 /* Maybe allow section after data2 - does this ever happen? */
801 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
802 {
803 if (NEW_PROGRAM_H (n).p_vaddr
804 && NEW_PROGRAM_H (n).p_vaddr >= new_data2_addr)
805 NEW_PROGRAM_H (n).p_vaddr += new_data2_size - old_bss_size;
806
807 if (NEW_PROGRAM_H (n).p_offset >= new_data2_offset)
808 NEW_PROGRAM_H (n).p_offset += new_data2_size;
809 }
810 #endif
811
812 /* Fix up section headers based on new .data2 section. Any section
813 * whose offset or virtual address is after the new .data2 section
814 * gets its value adjusted. .bss size becomes zero and new address
815 * is set. data2 section header gets added by copying the existing
816 * .data header and modifying the offset, address and size.
817 */
818 for (old_data_index = 1; old_data_index < (int) old_file_h->e_shnum;
819 old_data_index++)
820 if (!strcmp (old_section_names + OLD_SECTION_H (old_data_index).sh_name,
821 ".data"))
822 break;
823 if (old_data_index == old_file_h->e_shnum)
824 fatal ("Can't find .data in %s.\n", old_name, 0);
825
826 /* Walk through all section headers, insert the new data2 section right
827 before the new bss section. */
828 for (n = 1, nn = 1; n < (int) old_file_h->e_shnum; n++, nn++)
829 {
830 caddr_t src;
831 int temp_index;
832 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
833 /* If it is (s)bss section, insert the new data2 section before it. */
834 /* new_data2_index is the index of either old_sbss or old_bss, that was
835 chosen as a section for new_data2. */
836 temp_index = new_data2_index;
837 #else /* not (__sony_news && _SYSTYPE_SYSV) */
838 /* If it is bss section, insert the new data2 section before it. */
839 temp_index = old_bss_index;
840 #endif /* not (__sony_news && _SYSTYPE_SYSV) */
841 if (n == temp_index)
842 {
843 /* Steal the data section header for this data2 section. */
844 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (old_data_index),
845 new_file_h->e_shentsize);
846
847 NEW_SECTION_H (nn).sh_addr = new_data2_addr;
848 NEW_SECTION_H (nn).sh_offset = new_data2_offset;
849 NEW_SECTION_H (nn).sh_size = new_data2_size;
850 /* Use the bss section's alignment. This will assure that the
851 new data2 section always be placed in the same spot as the old
852 bss section by any other application. */
853 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (n).sh_addralign;
854
855 /* Now copy over what we have in the memory now. */
856 memcpy (NEW_SECTION_H (nn).sh_offset + new_base,
857 (caddr_t) OLD_SECTION_H (n).sh_addr,
858 new_data2_size);
859 nn++;
860 }
861
862 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n),
863 old_file_h->e_shentsize);
864
865 if (n == old_bss_index
866 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
867 /* The new bss and sbss section's size is zero, and its file offset
868 and virtual address should be off by NEW_DATA2_SIZE. */
869 || n == old_sbss_index
870 #endif /* __sony_news and _SYSTYPE_SYSV */
871 )
872 {
873 /* NN should be `old_bss_index + 1' at this point. */
874 NEW_SECTION_H (nn).sh_offset += new_data2_size;
875 NEW_SECTION_H (nn).sh_addr += new_data2_size;
876 /* Let the new bss section address alignment be the same as the
877 section address alignment followed the old bss section, so
878 this section will be placed in exactly the same place. */
879 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (nn).sh_addralign;
880 NEW_SECTION_H (nn).sh_size = 0;
881 }
882 else
883 {
884 /* Any section that was original placed AFTER the bss
885 section should now be off by NEW_DATA2_SIZE. */
886 #ifdef SOLARIS_POWERPC
887 /* On PPC Reference Platform running Solaris 2.5.1
888 the plt section is also of type NOBI like the bss section.
889 (not really stored) and therefore sections after the bss
890 section start at the plt offset. The plt section is always
891 the one just before the bss section.
892 It would be better to put the new data section before
893 the .plt section, or use libelf instead.
894 Erik Deumens, deumens@qtp.ufl.edu. */
895 if (NEW_SECTION_H (nn).sh_offset
896 >= OLD_SECTION_H (old_bss_index-1).sh_offset)
897 NEW_SECTION_H (nn).sh_offset += new_data2_size;
898 #else
899 if (round_up (NEW_SECTION_H (nn).sh_offset,
900 OLD_SECTION_H (old_bss_index).sh_addralign)
901 >= new_data2_offset)
902 NEW_SECTION_H (nn).sh_offset += new_data2_size;
903 #endif
904 /* Any section that was originally placed after the section
905 header table should now be off by the size of one section
906 header table entry. */
907 if (NEW_SECTION_H (nn).sh_offset > new_file_h->e_shoff)
908 NEW_SECTION_H (nn).sh_offset += new_file_h->e_shentsize;
909 }
910
911 /* If any section hdr refers to the section after the new .data
912 section, make it refer to next one because we have inserted
913 a new section in between. */
914
915 PATCH_INDEX (NEW_SECTION_H (nn).sh_link);
916 /* For symbol tables, info is a symbol table index,
917 so don't change it. */
918 if (NEW_SECTION_H (nn).sh_type != SHT_SYMTAB
919 && NEW_SECTION_H (nn).sh_type != SHT_DYNSYM)
920 PATCH_INDEX (NEW_SECTION_H (nn).sh_info);
921
922 /* Now, start to copy the content of sections. */
923 if (NEW_SECTION_H (nn).sh_type == SHT_NULL
924 || NEW_SECTION_H (nn).sh_type == SHT_NOBITS)
925 continue;
926
927 /* Write out the sections. .data and .data1 (and data2, called
928 ".data" in the strings table) get copied from the current process
929 instead of the old file. */
930 if (!strcmp (old_section_names + NEW_SECTION_H (n).sh_name, ".data")
931 #ifdef _nec_ews_svr4 /* hir, 1994.6.13 */
932 || !strcmp ((old_section_names + NEW_SECTION_H(n).sh_name),
933 ".sdata")
934 #endif
935 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
936 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
937 ".sdata")
938 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
939 ".lit4")
940 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
941 ".lit8")
942 #endif /* __sony_news && _SYSTYPE_SYSV */
943 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
944 ".data1"))
945 src = (caddr_t) OLD_SECTION_H (n).sh_addr;
946 else
947 src = old_base + OLD_SECTION_H (n).sh_offset;
948
949 memcpy (NEW_SECTION_H (nn).sh_offset + new_base, src,
950 NEW_SECTION_H (nn).sh_size);
951
952 #ifdef __alpha__
953 /* Update Alpha COFF symbol table: */
954 if (strcmp (old_section_names + OLD_SECTION_H (n).sh_name, ".mdebug")
955 == 0)
956 {
957 pHDRR symhdr = (pHDRR) (NEW_SECTION_H (nn).sh_offset + new_base);
958
959 symhdr->cbLineOffset += new_data2_size;
960 symhdr->cbDnOffset += new_data2_size;
961 symhdr->cbPdOffset += new_data2_size;
962 symhdr->cbSymOffset += new_data2_size;
963 symhdr->cbOptOffset += new_data2_size;
964 symhdr->cbAuxOffset += new_data2_size;
965 symhdr->cbSsOffset += new_data2_size;
966 symhdr->cbSsExtOffset += new_data2_size;
967 symhdr->cbFdOffset += new_data2_size;
968 symhdr->cbRfdOffset += new_data2_size;
969 symhdr->cbExtOffset += new_data2_size;
970 }
971 #endif /* __alpha__ */
972
973 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
974 if (NEW_SECTION_H (nn).sh_type == SHT_MIPS_DEBUG && old_mdebug_index)
975 {
976 int diff = NEW_SECTION_H(nn).sh_offset
977 - OLD_SECTION_H(old_mdebug_index).sh_offset;
978 HDRR *phdr = (HDRR *)(NEW_SECTION_H (nn).sh_offset + new_base);
979
980 if (diff)
981 {
982 phdr->cbLineOffset += diff;
983 phdr->cbDnOffset += diff;
984 phdr->cbPdOffset += diff;
985 phdr->cbSymOffset += diff;
986 phdr->cbOptOffset += diff;
987 phdr->cbAuxOffset += diff;
988 phdr->cbSsOffset += diff;
989 phdr->cbSsExtOffset += diff;
990 phdr->cbFdOffset += diff;
991 phdr->cbRfdOffset += diff;
992 phdr->cbExtOffset += diff;
993 }
994 }
995 #endif /* __sony_news && _SYSTYPE_SYSV */
996 /* If it is the symbol table, its st_shndx field needs to be patched. */
997 if (NEW_SECTION_H (nn).sh_type == SHT_SYMTAB
998 || NEW_SECTION_H (nn).sh_type == SHT_DYNSYM)
999 {
1000 ElfW(Shdr) *spt = &NEW_SECTION_H (nn);
1001 unsigned int num = spt->sh_size / spt->sh_entsize;
1002 ElfW(Sym) * sym = (ElfW(Sym) *) (NEW_SECTION_H (nn).sh_offset +
1003 new_base);
1004 for (; num--; sym++)
1005 {
1006 if ((sym->st_shndx == SHN_UNDEF)
1007 || (sym->st_shndx == SHN_ABS)
1008 || (sym->st_shndx == SHN_COMMON))
1009 continue;
1010
1011 PATCH_INDEX (sym->st_shndx);
1012 }
1013 }
1014 }
1015
1016 /* Update the symbol values of _edata and _end. */
1017 for (n = new_file_h->e_shnum - 1; n; n--)
1018 {
1019 byte *symnames;
1020 ElfW(Sym) *symp, *symendp;
1021
1022 if (NEW_SECTION_H (n).sh_type != SHT_DYNSYM
1023 && NEW_SECTION_H (n).sh_type != SHT_SYMTAB)
1024 continue;
1025
1026 symnames = ((byte *) new_base
1027 + NEW_SECTION_H (NEW_SECTION_H (n).sh_link).sh_offset);
1028 symp = (ElfW(Sym) *) (NEW_SECTION_H (n).sh_offset + new_base);
1029 symendp = (ElfW(Sym) *) ((byte *)symp + NEW_SECTION_H (n).sh_size);
1030
1031 for (; symp < symendp; symp ++)
1032 if (strcmp ((char *) (symnames + symp->st_name), "_end") == 0
1033 || strcmp ((char *) (symnames + symp->st_name), "_edata") == 0)
1034 memcpy (&symp->st_value, &new_bss_addr, sizeof (new_bss_addr));
1035 }
1036
1037 /* This loop seeks out relocation sections for the data section, so
1038 that it can undo relocations performed by the runtime linker. */
1039 for (n = new_file_h->e_shnum - 1; n; n--)
1040 {
1041 ElfW(Shdr) section = NEW_SECTION_H (n);
1042 switch (section.sh_type) {
1043 default:
1044 break;
1045 case SHT_REL:
1046 case SHT_RELA:
1047 /* This code handles two different size structs, but there should
1048 be no harm in that provided that r_offset is always the first
1049 member. */
1050 nn = section.sh_info;
1051 if (!strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".data")
1052 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1053 ".data1"))
1054 {
1055 ElfW(Addr) offset = NEW_SECTION_H (nn).sh_addr -
1056 NEW_SECTION_H (nn).sh_offset;
1057 caddr_t reloc = old_base + section.sh_offset, end;
1058 for (end = reloc + section.sh_size; reloc < end;
1059 reloc += section.sh_entsize)
1060 {
1061 ElfW(Addr) addr = ((ElfW(Rel) *) reloc)->r_offset - offset;
1062 #ifdef __alpha__
1063 /* The Alpha ELF binutils currently have a bug that
1064 sometimes results in relocs that contain all
1065 zeroes. Work around this for now... */
1066 if (((ElfW(Rel) *) reloc)->r_offset == 0)
1067 continue;
1068 #endif
1069 memcpy (new_base + addr, old_base + addr, sizeof(ElfW(Addr)));
1070 }
1071 }
1072 break;
1073 }
1074 }
1075
1076 #ifdef UNEXEC_USE_MAP_PRIVATE
1077 if (lseek (new_file, 0, SEEK_SET) == -1)
1078 fatal ("Can't rewind (%s): errno %d\n", new_name, errno);
1079
1080 if (write (new_file, new_base, new_file_size) != new_file_size)
1081 fatal ("Can't write (%s): errno %d\n", new_name, errno);
1082 #endif
1083
1084 /* Close the files and make the new file executable. */
1085
1086 if (close (old_file))
1087 fatal ("Can't close (%s): errno %d\n", old_name, errno);
1088
1089 if (close (new_file))
1090 fatal ("Can't close (%s): errno %d\n", new_name, errno);
1091
1092 if (stat (new_name, &stat_buf) == -1)
1093 fatal ("Can't stat (%s): errno %d\n", new_name, errno);
1094
1095 n = umask (777);
1096 umask (n);
1097 stat_buf.st_mode |= 0111 & ~n;
1098 if (chmod (new_name, stat_buf.st_mode) == -1)
1099 fatal ("Can't chmod (%s): errno %d\n", new_name, errno);
1100 }