HCoop / bpt / emacs.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
*** empty log message ***
[bpt/emacs.git] / src / unexsgi.c
CommitLineData
4ef37be4
JB		 1/* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992
2 Free Software Foundation, Inc.
3
3b7ad313 4This file is part of GNU Emacs.
4ef37be4 5
3b7ad313
EN		 6GNU Emacs is free software; you can redistribute it and/or modify
7it under the terms of the GNU General Public License as published by
8the Free Software Foundation; either version 2, or (at your option)
9any later version.
4ef37be4 10
3b7ad313
EN		 11GNU Emacs is distributed in the hope that it will be useful,
12but WITHOUT ANY WARRANTY; without even the implied warranty of
13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14GNU General Public License for more details.
15
16You should have received a copy of the GNU General Public License
17along with GNU Emacs; see the file COPYING. If not, write to
18the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19Boston, MA 02111-1307, USA.
4ef37be4
JB		 20
21In other words, you are welcome to use, share and improve this program.
22You are forbidden to forbid anyone else to use, share and improve
23what 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
95raid:/nfs/raid/src/dist-18.56/src> dump -h temacs
96
97temacs:
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
163raid:/nfs/raid/src/dist-18.56/src> dump -h xemacs
164
165xemacs:
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
243raid:/nfs/raid/src/dist-18.56/src> dump -f temacs
244
245temacs:
246
247 **** ELF HEADER ****
248Class Data Type Machine Version
249Entry Phoff Shoff Flags Ehsize
250Phentsize Phnum Shentsz Shnum Shstrndx
251
2521 1 2 3 1
2530x80499cc 0x34 0x792f4 0 0x34
2540x20 5 0x28 21 19
255
256raid:/nfs/raid/src/dist-18.56/src> dump -f xemacs
257
258xemacs:
259
260 **** ELF HEADER ****
261Class Data Type Machine Version
262Entry Phoff Shoff Flags Ehsize
263Phentsize Phnum Shentsz Shnum Shstrndx
264
2651 1 2 3 1
2660x80499cc 0x34 0x96200 0 0x34
2670x20 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
275raid:/nfs/raid/src/dist-18.56/src> dump -o temacs
276
277temacs:
278 ***** PROGRAM EXECUTION HEADER *****
279Type Offset Vaddr Paddr
280Filesz Memsz Flags Align
281
2826 0x34 0x8048034 0
2830xa0 0xa0 5 0
284
2853 0xd4 0 0
2860x13 0 4 0
287
2881 0x34 0x8048034 0
2890x3f2f9 0x3f2f9 5 0x1000
290
2911 0x3f330 0x8088330 0
2920x215c4 0x25a60 7 0x1000
293
2942 0x60874 0x80a9874 0
2950x80 0 7 0
296
297raid:/nfs/raid/src/dist-18.56/src> dump -o xemacs
298
299xemacs:
300 ***** PROGRAM EXECUTION HEADER *****
301Type Offset Vaddr Paddr
302Filesz Memsz Flags Align
303
3046 0x34 0x8048034 0
3050xa0 0xa0 5 0
306
3073 0xd4 0 0
3080x13 0 4 0
309
3101 0x34 0x8048034 0
3110x3f2f9 0x3f2f9 5 0x1000
312
3131 0x3f330 0x8088330 0
3140x3e4d0 0x3e4d0 7 0x1000
315
3162 0x60874 0x80a9874 0
3170x80 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
914eeff9 415#include <config.h>
4ef37be4
JB		 416#include <sys/types.h>
417#include <stdio.h>
418#include <sys/stat.h>
419#include <memory.h>
420#include <string.h>
421#include <errno.h>
422#include <unistd.h>
423#include <fcntl.h>
424#include <elf.h>
5416d1ee 425#include <syms.h> /* for HDRR declaration */
4ef37be4
JB		 426#include <sys/mman.h>
427
428#ifndef emacs
429#define fatal(a, b, c) fprintf(stderr, a, b, c), exit(1)
430#else
431extern void fatal(char *, ...);
432#endif
433
434/* Get the address of a particular section or program header entry,
435 * accounting for the size of the entries.
436 */
437
438#define OLD_SECTION_H(n) \
439 (*(Elf32_Shdr *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
440#define NEW_SECTION_H(n) \
441 (*(Elf32_Shdr *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
442#define OLD_PROGRAM_H(n) \
443 (*(Elf32_Phdr *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
444#define NEW_PROGRAM_H(n) \
445 (*(Elf32_Phdr *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
446
447#define PATCH_INDEX(n) \
448 do { \
449 if ((n) >= old_bss_index) \
450 (n)++; } while (0)
451typedef unsigned char byte;
452
453/* Round X up to a multiple of Y. */
454
455int
456round_up (x, y)
457 int x, y;
458{
459 int rem = x % y;
460 if (rem == 0)
461 return x;
462 return x - rem + y;
463}
464
49bb9833
RS		 465/* Return the index of the section named NAME.
466 SECTION_NAMES, FILE_NAME and FILE_H give information
467 about the file we are looking in.
468
469 If we don't find the section NAME, that is a fatal error
470 if NOERROR is 0; we return -1 if NOERROR is nonzero. */
471
472static int
ac5e49e9 473find_section (name, section_names, file_name, old_file_h, old_section_h, noerror)
49bb9833
RS		 474 char *name;
475 char *section_names;
476 char *file_name;
ac5e49e9
RS		 477 Elf32_Ehdr *old_file_h;
478 Elf32_Shdr *old_section_h;
49bb9833
RS		 479 int noerror;
480{
481 int idx;
482
ac5e49e9 483 for (idx = 1; idx < old_file_h->e_shnum; idx++)
49bb9833
RS		 484 {
485#ifdef DEBUG
486 fprintf (stderr, "Looking for %s - found %s\n", name,
487 section_names + OLD_SECTION_H (idx).sh_name);
488#endif
489 if (!strcmp (section_names + OLD_SECTION_H (idx).sh_name,
490 name))
491 break;
492 }
ac5e49e9 493 if (idx == old_file_h->e_shnum)
49bb9833
RS		 494 {
495 if (noerror)
496 return -1;
497 else
498 fatal ("Can't find .bss in %s.\n", file_name, 0);
499 }
500
501 return idx;
502}
503
4ef37be4
JB		 504/* ****************************************************************
505 * unexec
506 *
507 * driving logic.
508 *
509 * In ELF, this works by replacing the old .bss section with a new
510 * .data section, and inserting an empty .bss immediately afterwards.
511 *
512 */
513void
514unexec (new_name, old_name, data_start, bss_start, entry_address)
515 char *new_name, *old_name;
516 unsigned data_start, bss_start, entry_address;
517{
518 extern unsigned int bss_end;
519 int new_file, old_file, new_file_size;
520
5416d1ee 521 /* Pointers to the base of the image of the two files. */
4ef37be4
JB		 522 caddr_t old_base, new_base;
523
524 /* Pointers to the file, program and section headers for the old and new
5416d1ee 525 files. */
4ef37be4
JB		 526 Elf32_Ehdr *old_file_h, *new_file_h;
527 Elf32_Phdr *old_program_h, *new_program_h;
528 Elf32_Shdr *old_section_h, *new_section_h;
529
5416d1ee 530 /* Point to the section name table in the old file. */
4ef37be4
JB		 531 char *old_section_names;
532
533 Elf32_Addr old_bss_addr, new_bss_addr;
534 Elf32_Word old_bss_size, new_data2_size;
535 Elf32_Off new_data2_offset;
536 Elf32_Addr new_data2_addr;
f5abdb04 537 Elf32_Addr new_offsets_shift;
4ef37be4
JB		 538
539 int n, nn, old_bss_index, old_data_index, new_data2_index;
5416d1ee 540 int old_mdebug_index;
4ef37be4
JB		 541 struct stat stat_buf;
542
5416d1ee 543 /* Open the old file & map it into the address space. */
4ef37be4
JB		 544
545 old_file = open (old_name, O_RDONLY);
546
547 if (old_file < 0)
548 fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
549
550 if (fstat (old_file, &stat_buf) == -1)
551 fatal ("Can't fstat(%s): errno %d\n", old_name, errno);
552
553 old_base = mmap (0, stat_buf.st_size, PROT_READ, MAP_SHARED, old_file, 0);
554
555 if (old_base == (caddr_t) -1)
556 fatal ("Can't mmap(%s): errno %d\n", old_name, errno);
557
558#ifdef DEBUG
559 fprintf (stderr, "mmap(%s, %x) -> %x\n", old_name, stat_buf.st_size,
560 old_base);
561#endif
562
5416d1ee 563 /* Get pointers to headers & section names. */
4ef37be4
JB		 564
565 old_file_h = (Elf32_Ehdr *) old_base;
566 old_program_h = (Elf32_Phdr *) ((byte *) old_base + old_file_h->e_phoff);
567 old_section_h = (Elf32_Shdr *) ((byte *) old_base + old_file_h->e_shoff);
5416d1ee
RS		 568 old_section_names
569 = (char *) old_base + OLD_SECTION_H (old_file_h->e_shstrndx).sh_offset;
570
571 /* Find the mdebug section, if any. */
49bb9833
RS		 572
573 old_mdebug_index = find_section (".mdebug", old_section_names,
ac5e49e9 574 old_name, old_file_h, old_section_h, 1);
4ef37be4 575
f5abdb04 576 /* Find the old .bss section. */
4ef37be4 577
49bb9833 578 old_bss_index = find_section (".bss", old_section_names,
ac5e49e9 579 old_name, old_file_h, old_section_h, 0);
4ef37be4 580
f5abdb04
RS		 581 /* Find the old .data section. Figure out parameters of
582 the new data2 and bss sections. */
583
49bb9833 584 old_data_index = find_section (".data", old_section_names,
ac5e49e9 585 old_name, old_file_h, old_section_h, 0);
f5abdb04 586
5416d1ee
RS		 587 old_bss_addr = OLD_SECTION_H (old_bss_index).sh_addr;
588 old_bss_size = OLD_SECTION_H (old_bss_index).sh_size;
4ef37be4
JB		 589#if defined(emacs) || !defined(DEBUG)
590 bss_end = (unsigned int) sbrk (0);
591 new_bss_addr = (Elf32_Addr) bss_end;
592#else
593 new_bss_addr = old_bss_addr + old_bss_size + 0x1234;
594#endif
595 new_data2_addr = old_bss_addr;
596 new_data2_size = new_bss_addr - old_bss_addr;
f5abdb04
RS		 597 new_data2_offset = OLD_SECTION_H (old_data_index).sh_offset +
598 (new_data2_addr - OLD_SECTION_H (old_data_index).sh_addr);
599 new_offsets_shift = new_bss_addr -
600 ((old_bss_addr & ~0xfff) + ((old_bss_addr & 0xfff) ? 0x1000 : 0));
4ef37be4
JB		 601
602#ifdef DEBUG
603 fprintf (stderr, "old_bss_index %d\n", old_bss_index);
604 fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
605 fprintf (stderr, "old_bss_size %x\n", old_bss_size);
606 fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
607 fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
608 fprintf (stderr, "new_data2_size %x\n", new_data2_size);
609 fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
f5abdb04 610 fprintf (stderr, "new_offsets_shift %x\n", new_offsets_shift);
4ef37be4
JB		 611#endif
612
613 if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
614 fatal (".bss shrank when undumping???\n", 0, 0);
615
5416d1ee
RS		 616 /* Set the output file to the right size and mmap it. Set
617 pointers to various interesting objects. stat_buf still has
618 old_file data. */
4ef37be4
JB		 619
620 new_file = open (new_name, O_RDWR | O_CREAT, 0666);
621 if (new_file < 0)
5416d1ee 622 fatal ("Can't creat (%s): errno %d\n", new_name, errno);
4ef37be4 623
f5abdb04 624 new_file_size = stat_buf.st_size + old_file_h->e_shentsize + new_offsets_shift;
4ef37be4
JB		 625
626 if (ftruncate (new_file, new_file_size))
5416d1ee 627 fatal ("Can't ftruncate (%s): errno %d\n", new_name, errno);
4ef37be4
JB		 628
629 new_base = mmap (0, new_file_size, PROT_READ | PROT_WRITE, MAP_SHARED,
630 new_file, 0);
631
632 if (new_base == (caddr_t) -1)
5416d1ee 633 fatal ("Can't mmap (%s): errno %d\n", new_name, errno);
4ef37be4
JB		 634
635 new_file_h = (Elf32_Ehdr *) new_base;
636 new_program_h = (Elf32_Phdr *) ((byte *) new_base + old_file_h->e_phoff);
5416d1ee
RS		 637 new_section_h
638 = (Elf32_Shdr *) ((byte *) new_base + old_file_h->e_shoff
f5abdb04 639 + new_offsets_shift);
4ef37be4
JB		 640
641 /* Make our new file, program and section headers as copies of the
5416d1ee 642 originals. */
4ef37be4
JB		 643
644 memcpy (new_file_h, old_file_h, old_file_h->e_ehsize);
645 memcpy (new_program_h, old_program_h,
646 old_file_h->e_phnum * old_file_h->e_phentsize);
647
648 /* Modify the e_shstrndx if necessary. */
649 PATCH_INDEX (new_file_h->e_shstrndx);
650
651 /* Fix up file header. We'll add one section. Section header is
5416d1ee 652 further away now. */
4ef37be4 653
f5abdb04 654 new_file_h->e_shoff += new_offsets_shift;
4ef37be4
JB		 655 new_file_h->e_shnum += 1;
656
657#ifdef DEBUG
658 fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff);
659 fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum);
660 fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff);
661 fprintf (stderr, "New section count %d\n", new_file_h->e_shnum);
662#endif
663
664 /* Fix up a new program header. Extend the writable data segment so
5416d1ee
RS		 665 that the bss area is covered too. Find that segment by looking
666 for a segment that ends just before the .bss area. Make sure
667 that no segments are above the new .data2. Put a loop at the end
668 to adjust the offset and address of any segment that is above
669 data2, just in case we decide to allow this later. */
4ef37be4
JB		 670
671 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
672 {
673 /* Compute maximum of all requirements for alignment of section. */
674 int alignment = (NEW_PROGRAM_H (n)).p_align;
675 if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment)
676 alignment = OLD_SECTION_H (old_bss_index).sh_addralign;
677
7260e339
JB		 678 /* Supposedly this condition is okay for the SGI. */
679#if 0
5416d1ee 680 if (NEW_PROGRAM_H (n).p_vaddr + NEW_PROGRAM_H (n).p_filesz > old_bss_addr)
4ef37be4 681 fatal ("Program segment above .bss in %s\n", old_name, 0);
7260e339 682#endif
4ef37be4 683
5416d1ee 684 if (NEW_PROGRAM_H (n).p_type == PT_LOAD
4ef37be4
JB		 685 && (round_up ((NEW_PROGRAM_H (n)).p_vaddr
686 + (NEW_PROGRAM_H (n)).p_filesz,
687 alignment)
688 == round_up (old_bss_addr, alignment)))
689 break;
690 }
691 if (n < 0)
692 fatal ("Couldn't find segment next to .bss in %s\n", old_name, 0);
693
f5abdb04 694 NEW_PROGRAM_H (n).p_filesz += new_offsets_shift;
5416d1ee 695 NEW_PROGRAM_H (n).p_memsz = NEW_PROGRAM_H (n).p_filesz;
4ef37be4 696
f5abdb04 697#if 1 /* Maybe allow section after data2 - does this ever happen? */
4ef37be4
JB		 698 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
699 {
5416d1ee
RS		 700 if (NEW_PROGRAM_H (n).p_vaddr
701 && NEW_PROGRAM_H (n).p_vaddr >= new_data2_addr)
f5abdb04 702 NEW_PROGRAM_H (n).p_vaddr += new_offsets_shift - old_bss_size;
4ef37be4 703
5416d1ee 704 if (NEW_PROGRAM_H (n).p_offset >= new_data2_offset)
f5abdb04 705 NEW_PROGRAM_H (n).p_offset += new_offsets_shift;
4ef37be4
JB		 706 }
707#endif
708
709 /* Fix up section headers based on new .data2 section. Any section
5416d1ee
RS		 710 whose offset or virtual address is after the new .data2 section
711 gets its value adjusted. .bss size becomes zero and new address
712 is set. data2 section header gets added by copying the existing
713 .data header and modifying the offset, address and size. */
4ef37be4
JB		 714 for (old_data_index = 1; old_data_index < old_file_h->e_shnum;
715 old_data_index++)
5416d1ee 716 if (!strcmp (old_section_names + OLD_SECTION_H (old_data_index).sh_name,
4ef37be4
JB		 717 ".data"))
718 break;
719 if (old_data_index == old_file_h->e_shnum)
720 fatal ("Can't find .data in %s.\n", old_name, 0);
721
722 /* Walk through all section headers, insert the new data2 section right
5416d1ee 723 before the new bss section. */
4ef37be4
JB		 724 for (n = 1, nn = 1; n < old_file_h->e_shnum; n++, nn++)
725 {
726 caddr_t src;
f5abdb04 727
49bb9833
RS		 728 /* If it is bss section, insert the new data2 section before it. */
729 if (n == old_bss_index)
4ef37be4 730 {
5416d1ee
RS		 731 /* Steal the data section header for this data2 section. */
732 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (old_data_index),
4ef37be4
JB		 733 new_file_h->e_shentsize);
734
5416d1ee
RS		 735 NEW_SECTION_H (nn).sh_addr = new_data2_addr;
736 NEW_SECTION_H (nn).sh_offset = new_data2_offset;
737 NEW_SECTION_H (nn).sh_size = new_data2_size;
4ef37be4
JB		 738 /* Use the bss section's alignment. This will assure that the
739 new data2 section always be placed in the same spot as the old
5416d1ee
RS		 740 bss section by any other application. */
741 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (n).sh_addralign;
4ef37be4 742
5416d1ee
RS		 743 /* Now copy over what we have in the memory now. */
744 memcpy (NEW_SECTION_H (nn).sh_offset + new_base,
745 (caddr_t) OLD_SECTION_H (n).sh_addr,
4ef37be4
JB		 746 new_data2_size);
747 nn++;
f5abdb04
RS		 748 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n),
749 old_file_h->e_shentsize);
4ef37be4 750
f5abdb04
RS		 751 /* The new bss section's size is zero, and its file offset and virtual
752 address should be off by NEW_OFFSETS_SHIFT. */
753 NEW_SECTION_H (nn).sh_offset += new_offsets_shift;
754 NEW_SECTION_H (nn).sh_addr = new_bss_addr;
4ef37be4
JB		 755 /* Let the new bss section address alignment be the same as the
756 section address alignment followed the old bss section, so
5416d1ee
RS		 757 this section will be placed in exactly the same place. */
758 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (nn).sh_addralign;
759 NEW_SECTION_H (nn).sh_size = 0;
4ef37be4 760 }
49bb9833 761 else
914eeff9
KH		 762 {
763 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n),
764 old_file_h->e_shentsize);
f5abdb04 765
914eeff9
KH		 766 /* Any section that was original placed AFTER the bss
767 section must now be adjusted by NEW_OFFSETS_SHIFT. */
768
769 if (NEW_SECTION_H (nn).sh_offset >= new_data2_offset)
770 NEW_SECTION_H (nn).sh_offset += new_offsets_shift;
771 }
f5abdb04 772
4ef37be4
JB		 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
5416d1ee 775 a new section in between. */
4ef37be4 776
5416d1ee 777 PATCH_INDEX (NEW_SECTION_H (nn).sh_link);
019f2b8f
RS		 778 /* For symbol tables, info is a symbol table index,
779 so don't change it. */
780 if (NEW_SECTION_H (nn).sh_type != SHT_SYMTAB
781 && NEW_SECTION_H (nn).sh_type != SHT_DYNSYM)
782 PATCH_INDEX (NEW_SECTION_H (nn).sh_info);
4ef37be4
JB		 783
784 /* Now, start to copy the content of sections. */
5416d1ee
RS		 785 if (NEW_SECTION_H (nn).sh_type == SHT_NULL
786 || NEW_SECTION_H (nn).sh_type == SHT_NOBITS)
4ef37be4
JB		 787 continue;
788
789 /* Write out the sections. .data and .data1 (and data2, called
5416d1ee
RS		 790 ".data" in the strings table) get copied from the current process
791 instead of the old file. */
914eeff9
KH		 792 if (!strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".data")
793 || !strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".data1")
794#ifdef IRIX6_5
795 /* Under IRIX 6.5 gcc places objects with adresses relative to
796 shared symbols in the section .rodata, which are adjusted at
797 startup time. Unfortunately they aren't adjusted after unexec,
798 so with this configuration we must get .rodata also from memory.
799 Do any other configurations need this, too?
800 <Wolfgang.Glas@hfm.tu-graz.ac.at> 1999-06-08. */
801 || !strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".rodata")
802#endif
803 || !strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".got"))
5416d1ee 804 src = (caddr_t) OLD_SECTION_H (n).sh_addr;
4ef37be4 805 else
5416d1ee 806 src = old_base + OLD_SECTION_H (n).sh_offset;
4ef37be4 807
5416d1ee
RS		 808 memcpy (NEW_SECTION_H (nn).sh_offset + new_base, src,
809 NEW_SECTION_H (nn).sh_size);
810
811 /* Adjust the HDRR offsets in .mdebug and copy the
812 line data if it's in its usual 'hole' in the object.
813 Makes the new file debuggable with dbx.
814 patches up two problems: the absolute file offsets
815 in the HDRR record of .mdebug (see /usr/include/syms.h), and
816 the ld bug that gets the line table in a hole in the
817 elf file rather than in the .mdebug section proper.
818 David Anderson. davea@sgi.com Jan 16,1994. */
819 if (n == old_mdebug_index)
820 {
821#define MDEBUGADJUST(__ct,__fileaddr) \
822 if (n_phdrr->__ct > 0) \
823 { \
824 n_phdrr->__fileaddr += movement; \
825 }
826
f5abdb04
RS		 827 HDRR * o_phdrr = (HDRR *)((byte *)old_base + OLD_SECTION_H (n).sh_offset);
828 HDRR * n_phdrr = (HDRR *)((byte *)new_base + NEW_SECTION_H (nn).sh_offset);
829 unsigned movement = new_offsets_shift;
830
831 MDEBUGADJUST (idnMax, cbDnOffset);
832 MDEBUGADJUST (ipdMax, cbPdOffset);
833 MDEBUGADJUST (isymMax, cbSymOffset);
834 MDEBUGADJUST (ioptMax, cbOptOffset);
835 MDEBUGADJUST (iauxMax, cbAuxOffset);
836 MDEBUGADJUST (issMax, cbSsOffset);
837 MDEBUGADJUST (issExtMax, cbSsExtOffset);
838 MDEBUGADJUST (ifdMax, cbFdOffset);
839 MDEBUGADJUST (crfd, cbRfdOffset);
840 MDEBUGADJUST (iextMax, cbExtOffset);
841 /* The Line Section, being possible off in a hole of the object,
842 requires special handling. */
843 if (n_phdrr->cbLine > 0)
844 {
845 if (o_phdrr->cbLineOffset > (OLD_SECTION_H (n).sh_offset
846 + OLD_SECTION_H (n).sh_size))
847 {
848 /* line data is in a hole in elf. do special copy and adjust
849 for this ld mistake.
850 */
851 n_phdrr->cbLineOffset += movement;
852
853 memcpy (n_phdrr->cbLineOffset + new_base,
854 o_phdrr->cbLineOffset + old_base, n_phdrr->cbLine);
855 }
856 else
857 {
858 /* somehow line data is in .mdebug as it is supposed to be. */
859 MDEBUGADJUST (cbLine, cbLineOffset);
860 }
861 }
862 }
4ef37be4
JB		 863
864 /* If it is the symbol table, its st_shndx field needs to be patched. */
5416d1ee
RS		 865 if (NEW_SECTION_H (nn).sh_type == SHT_SYMTAB
866 || NEW_SECTION_H (nn).sh_type == SHT_DYNSYM)
4ef37be4 867 {
5416d1ee 868 Elf32_Shdr *spt = &NEW_SECTION_H (nn);
4ef37be4 869 unsigned int num = spt->sh_size / spt->sh_entsize;
5416d1ee
RS		 870 Elf32_Sym * sym = (Elf32_Sym *) (NEW_SECTION_H (nn).sh_offset
871 + new_base);
4ef37be4
JB		 872 for (; num--; sym++)
873 {
914eeff9 874 /* don't patch special section indices. */
5416d1ee 875 if (sym->st_shndx == SHN_UNDEF
914eeff9 876 || sym->st_shndx >= SHN_LORESERVE)
4ef37be4
JB		 877 continue;
878
5416d1ee 879 PATCH_INDEX (sym->st_shndx);
4ef37be4
JB		 880 }
881 }
882 }
883
5416d1ee 884 /* Close the files and make the new file executable. */
4ef37be4
JB		 885
886 if (close (old_file))
5416d1ee 887 fatal ("Can't close (%s): errno %d\n", old_name, errno);
4ef37be4
JB		 888
889 if (close (new_file))
5416d1ee 890 fatal ("Can't close (%s): errno %d\n", new_name, errno);
4ef37be4
JB		 891
892 if (stat (new_name, &stat_buf) == -1)
5416d1ee 893 fatal ("Can't stat (%s): errno %d\n", new_name, errno);
4ef37be4
JB		 894
895 n = umask (777);
896 umask (n);
897 stat_buf.st_mode |= 0111 & ~n;
898 if (chmod (new_name, stat_buf.st_mode) == -1)
5416d1ee 899 fatal ("Can't chmod (%s): errno %d\n", new_name, errno);
4ef37be4 900}
Unnamed repository; edit this file 'description' to name the repository.