* configure.in: Use macppc for Darwin.
[bpt/emacs.git] / src / unexelf.c
CommitLineData
0b5538bd 1/* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992, 1999, 2000, 2001,
8cabe764
GM
2 2002, 2003, 2004, 2005, 2006, 2007, 2008
3 Free Software Foundation, Inc.
d427b66a 4
3b7ad313 5This file is part of GNU Emacs.
e40c4104 6
9ec0b715 7GNU Emacs is free software: you can redistribute it and/or modify
3b7ad313 8it under the terms of the GNU General Public License as published by
9ec0b715
GM
9the Free Software Foundation, either version 3 of the License, or
10(at your option) any later version.
e40c4104 11
3b7ad313
EN
12GNU Emacs is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
9ec0b715 18along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */
d427b66a 19
9ec0b715 20/*
d427b66a
JB
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:
89b95605
RS
36 * unexec (new_name, old_name, data_start, bss_start, entry_address)
37 * char *new_name, *old_name;
d427b66a
JB
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.
89b95605
RS
42 * If old_name is non-NULL, the symbol table will be taken from the given file.
43 * On some machines, an existing old_name file is required.
d427b66a
JB
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 *
d427b66a
JB
55 * Bss_start indicates how much of the data segment is to be saved in the
56 * a.out file and restored when the program is executed. It gives the lowest
57 * unsaved address, and is rounded up to a page boundary. The default when 0
58 * is given assumes that the entire data segment is to be stored, including
59 * the previous data and bss as well as any additional storage allocated with
60 * break (2).
61 *
62 * The new file is set up to start at entry_address.
63 *
d427b66a
JB
64 */
65
66/* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
67 * ELF support added.
68 *
69 * Basic theory: the data space of the running process needs to be
70 * dumped to the output file. Normally we would just enlarge the size
71 * of .data, scooting everything down. But we can't do that in ELF,
72 * because there is often something between the .data space and the
73 * .bss space.
74 *
75 * In the temacs dump below, notice that the Global Offset Table
76 * (.got) and the Dynamic link data (.dynamic) come between .data1 and
77 * .bss. It does not work to overlap .data with these fields.
78 *
79 * The solution is to create a new .data segment. This segment is
80 * filled with data from the current process. Since the contents of
81 * various sections refer to sections by index, the new .data segment
82 * is made the last in the table to avoid changing any existing index.
83
84 * This is an example of how the section headers are changed. "Addr"
85 * is a process virtual address. "Offset" is a file offset.
86
87raid:/nfs/raid/src/dist-18.56/src> dump -h temacs
88
89temacs:
90
91 **** SECTION HEADER TABLE ****
7da3d06f
DL
92 [No] Type Flags Addr Offset Size Name
93 Link Info Adralgn Entsize
d427b66a 94
7da3d06f
DL
95 [1] 1 2 0x80480d4 0xd4 0x13 .interp
96 0 0 0x1 0
d427b66a 97
7da3d06f
DL
98 [2] 5 2 0x80480e8 0xe8 0x388 .hash
99 3 0 0x4 0x4
d427b66a 100
7da3d06f
DL
101 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
102 4 1 0x4 0x10
d427b66a 103
7da3d06f
DL
104 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
105 0 0 0x1 0
d427b66a 106
7da3d06f
DL
107 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
108 3 7 0x4 0x8
d427b66a 109
7da3d06f
DL
110 [6] 1 6 0x8049348 0x1348 0x3 .init
111 0 0 0x4 0
d427b66a 112
7da3d06f
DL
113 [7] 1 6 0x804934c 0x134c 0x680 .plt
114 0 0 0x4 0x4
d427b66a 115
7da3d06f
DL
116 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
117 0 0 0x4 0
d427b66a 118
7da3d06f
DL
119 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
120 0 0 0x4 0
d427b66a 121
7da3d06f
DL
122 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
123 0 0 0x4 0
d427b66a 124
7da3d06f
DL
125 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
126 0 0 0x4 0
d427b66a 127
7da3d06f
DL
128 [12] 1 3 0x8088330 0x3f330 0x20afc .data
129 0 0 0x4 0
d427b66a 130
7da3d06f
DL
131 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
132 0 0 0x4 0
d427b66a 133
7da3d06f
DL
134 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
135 0 0 0x4 0x4
d427b66a 136
7da3d06f
DL
137 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
138 4 0 0x4 0x8
d427b66a 139
7da3d06f
DL
140 [16] 8 3 0x80a98f4 0x608f4 0x449c .bss
141 0 0 0x4 0
d427b66a 142
7da3d06f
DL
143 [17] 2 0 0 0x608f4 0x9b90 .symtab
144 18 371 0x4 0x10
d427b66a 145
7da3d06f
DL
146 [18] 3 0 0 0x6a484 0x8526 .strtab
147 0 0 0x1 0
d427b66a 148
7da3d06f
DL
149 [19] 3 0 0 0x729aa 0x93 .shstrtab
150 0 0 0x1 0
d427b66a 151
7da3d06f
DL
152 [20] 1 0 0 0x72a3d 0x68b7 .comment
153 0 0 0x1 0
d427b66a 154
7da3d06f 155 raid:/nfs/raid/src/dist-18.56/src> dump -h xemacs
d427b66a 156
7da3d06f 157 xemacs:
d427b66a 158
7da3d06f
DL
159 **** SECTION HEADER TABLE ****
160 [No] Type Flags Addr Offset Size Name
161 Link Info Adralgn Entsize
d427b66a 162
7da3d06f
DL
163 [1] 1 2 0x80480d4 0xd4 0x13 .interp
164 0 0 0x1 0
d427b66a 165
7da3d06f
DL
166 [2] 5 2 0x80480e8 0xe8 0x388 .hash
167 3 0 0x4 0x4
d427b66a 168
7da3d06f
DL
169 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
170 4 1 0x4 0x10
d427b66a 171
7da3d06f
DL
172 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
173 0 0 0x1 0
d427b66a 174
7da3d06f
DL
175 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
176 3 7 0x4 0x8
d427b66a 177
7da3d06f
DL
178 [6] 1 6 0x8049348 0x1348 0x3 .init
179 0 0 0x4 0
d427b66a 180
7da3d06f
DL
181 [7] 1 6 0x804934c 0x134c 0x680 .plt
182 0 0 0x4 0x4
d427b66a 183
7da3d06f
DL
184 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
185 0 0 0x4 0
d427b66a 186
7da3d06f
DL
187 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
188 0 0 0x4 0
d427b66a 189
7da3d06f
DL
190 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
191 0 0 0x4 0
d427b66a 192
7da3d06f
DL
193 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
194 0 0 0x4 0
d427b66a 195
7da3d06f
DL
196 [12] 1 3 0x8088330 0x3f330 0x20afc .data
197 0 0 0x4 0
d427b66a 198
7da3d06f
DL
199 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
200 0 0 0x4 0
d427b66a 201
7da3d06f
DL
202 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
203 0 0 0x4 0x4
d427b66a 204
7da3d06f
DL
205 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
206 4 0 0x4 0x8
d427b66a 207
7da3d06f
DL
208 [16] 8 3 0x80c6800 0x7d800 0 .bss
209 0 0 0x4 0
d427b66a 210
7da3d06f
DL
211 [17] 2 0 0 0x7d800 0x9b90 .symtab
212 18 371 0x4 0x10
d427b66a 213
7da3d06f
DL
214 [18] 3 0 0 0x87390 0x8526 .strtab
215 0 0 0x1 0
d427b66a 216
7da3d06f
DL
217 [19] 3 0 0 0x8f8b6 0x93 .shstrtab
218 0 0 0x1 0
d427b66a 219
7da3d06f
DL
220 [20] 1 0 0 0x8f949 0x68b7 .comment
221 0 0 0x1 0
d427b66a 222
7da3d06f
DL
223 [21] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
224 0 0 0x4 0
d427b66a 225
7da3d06f
DL
226 * This is an example of how the file header is changed. "Shoff" is
227 * the section header offset within the file. Since that table is
228 * after the new .data section, it is moved. "Shnum" is the number of
229 * sections, which we increment.
230 *
231 * "Phoff" is the file offset to the program header. "Phentsize" and
232 * "Shentsz" are the program and section header entries sizes respectively.
233 * These can be larger than the apparent struct sizes.
d427b66a 234
7da3d06f 235 raid:/nfs/raid/src/dist-18.56/src> dump -f temacs
d427b66a 236
7da3d06f 237 temacs:
d427b66a 238
7da3d06f
DL
239 **** ELF HEADER ****
240 Class Data Type Machine Version
241 Entry Phoff Shoff Flags Ehsize
242 Phentsize Phnum Shentsz Shnum Shstrndx
d427b66a 243
7da3d06f
DL
244 1 1 2 3 1
245 0x80499cc 0x34 0x792f4 0 0x34
246 0x20 5 0x28 21 19
d427b66a 247
7da3d06f 248 raid:/nfs/raid/src/dist-18.56/src> dump -f xemacs
d427b66a 249
7da3d06f 250 xemacs:
d427b66a 251
7da3d06f
DL
252 **** ELF HEADER ****
253 Class Data Type Machine Version
254 Entry Phoff Shoff Flags Ehsize
255 Phentsize Phnum Shentsz Shnum Shstrndx
d427b66a 256
7da3d06f
DL
257 1 1 2 3 1
258 0x80499cc 0x34 0x96200 0 0x34
259 0x20 5 0x28 22 19
d427b66a 260
7da3d06f
DL
261 * These are the program headers. "Offset" is the file offset to the
262 * segment. "Vaddr" is the memory load address. "Filesz" is the
263 * segment size as it appears in the file, and "Memsz" is the size in
264 * memory. Below, the third segment is the code and the fourth is the
265 * data: the difference between Filesz and Memsz is .bss
d427b66a 266
7da3d06f 267 raid:/nfs/raid/src/dist-18.56/src> dump -o temacs
d427b66a 268
7da3d06f
DL
269 temacs:
270 ***** PROGRAM EXECUTION HEADER *****
271 Type Offset Vaddr Paddr
272 Filesz Memsz Flags Align
d427b66a 273
7da3d06f
DL
274 6 0x34 0x8048034 0
275 0xa0 0xa0 5 0
d427b66a 276
7da3d06f
DL
277 3 0xd4 0 0
278 0x13 0 4 0
d427b66a 279
7da3d06f
DL
280 1 0x34 0x8048034 0
281 0x3f2f9 0x3f2f9 5 0x1000
d427b66a 282
7da3d06f
DL
283 1 0x3f330 0x8088330 0
284 0x215c4 0x25a60 7 0x1000
d427b66a 285
7da3d06f
DL
286 2 0x60874 0x80a9874 0
287 0x80 0 7 0
d427b66a 288
7da3d06f 289 raid:/nfs/raid/src/dist-18.56/src> dump -o xemacs
d427b66a 290
7da3d06f
DL
291 xemacs:
292 ***** PROGRAM EXECUTION HEADER *****
293 Type Offset Vaddr Paddr
294 Filesz Memsz Flags Align
d427b66a 295
7da3d06f
DL
296 6 0x34 0x8048034 0
297 0xa0 0xa0 5 0
d427b66a 298
7da3d06f
DL
299 3 0xd4 0 0
300 0x13 0 4 0
d427b66a 301
7da3d06f
DL
302 1 0x34 0x8048034 0
303 0x3f2f9 0x3f2f9 5 0x1000
d427b66a 304
7da3d06f
DL
305 1 0x3f330 0x8088330 0
306 0x3e4d0 0x3e4d0 7 0x1000
d427b66a 307
7da3d06f
DL
308 2 0x60874 0x80a9874 0
309 0x80 0 7 0
d427b66a
JB
310
311
312 */
e40c4104 313\f
994a65f3
RM
314/* Modified by wtien@urbana.mcd.mot.com of Motorola Inc.
315 *
e40c4104 316 * The above mechanism does not work if the unexeced ELF file is being
994a65f3 317 * re-layout by other applications (such as `strip'). All the applications
e40c4104 318 * that re-layout the internal of ELF will layout all sections in ascending
994a65f3
RM
319 * order of their file offsets. After the re-layout, the data2 section will
320 * still be the LAST section in the section header vector, but its file offset
e40c4104 321 * is now being pushed far away down, and causes part of it not to be mapped
994a65f3 322 * in (ie. not covered by the load segment entry in PHDR vector), therefore
e40c4104
RS
323 * causes the new binary to fail.
324 *
325 * The solution is to modify the unexec algorithm to insert the new data2
326 * section header right before the new bss section header, so their file
994a65f3
RM
327 * offsets will be in the ascending order. Since some of the section's (all
328 * sections AFTER the bss section) indexes are now changed, we also need to
329 * modify some fields to make them point to the right sections. This is done
e40c4104 330 * by macro PATCH_INDEX. All the fields that need to be patched are:
994a65f3 331 *
e40c4104
RS
332 * 1. ELF header e_shstrndx field.
333 * 2. section header sh_link and sh_info field.
334 * 3. symbol table entry st_shndx field.
335 *
336 * The above example now should look like:
337
338 **** SECTION HEADER TABLE ****
7da3d06f
DL
339 [No] Type Flags Addr Offset Size Name
340 Link Info Adralgn Entsize
e40c4104 341
7da3d06f
DL
342 [1] 1 2 0x80480d4 0xd4 0x13 .interp
343 0 0 0x1 0
d427b66a 344
7da3d06f
DL
345 [2] 5 2 0x80480e8 0xe8 0x388 .hash
346 3 0 0x4 0x4
e40c4104 347
7da3d06f
DL
348 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
349 4 1 0x4 0x10
e40c4104 350
7da3d06f
DL
351 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
352 0 0 0x1 0
e40c4104 353
7da3d06f
DL
354 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
355 3 7 0x4 0x8
e40c4104 356
7da3d06f
DL
357 [6] 1 6 0x8049348 0x1348 0x3 .init
358 0 0 0x4 0
e40c4104 359
7da3d06f
DL
360 [7] 1 6 0x804934c 0x134c 0x680 .plt
361 0 0 0x4 0x4
e40c4104 362
7da3d06f
DL
363 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
364 0 0 0x4 0
e40c4104 365
7da3d06f
DL
366 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
367 0 0 0x4 0
e40c4104 368
7da3d06f
DL
369 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
370 0 0 0x4 0
e40c4104 371
7da3d06f
DL
372 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
373 0 0 0x4 0
e40c4104 374
7da3d06f
DL
375 [12] 1 3 0x8088330 0x3f330 0x20afc .data
376 0 0 0x4 0
e40c4104 377
7da3d06f
DL
378 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
379 0 0 0x4 0
e40c4104 380
7da3d06f
DL
381 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
382 0 0 0x4 0x4
e40c4104 383
7da3d06f
DL
384 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
385 4 0 0x4 0x8
e40c4104 386
7da3d06f
DL
387 [16] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
388 0 0 0x4 0
e40c4104 389
7da3d06f
DL
390 [17] 8 3 0x80c6800 0x7d800 0 .bss
391 0 0 0x4 0
e40c4104 392
7da3d06f
DL
393 [18] 2 0 0 0x7d800 0x9b90 .symtab
394 19 371 0x4 0x10
e40c4104 395
7da3d06f
DL
396 [19] 3 0 0 0x87390 0x8526 .strtab
397 0 0 0x1 0
e40c4104 398
7da3d06f
DL
399 [20] 3 0 0 0x8f8b6 0x93 .shstrtab
400 0 0 0x1 0
e40c4104 401
7da3d06f
DL
402 [21] 1 0 0 0x8f949 0x68b7 .comment
403 0 0 0x1 0
e40c4104
RS
404
405 */
406\f
d9d54213
RS
407/* We do not use mmap because that fails with NFS.
408 Instead we read the whole file, modify it, and write it out. */
409
1b963cdd
DL
410#ifndef emacs
411#define fatal(a, b, c) fprintf (stderr, a, b, c), exit (1)
6b7d4ae4 412#include <string.h>
1b963cdd
DL
413#else
414#include <config.h>
fa8459a3 415extern void fatal (const char *msgid, ...);
1b963cdd
DL
416#endif
417
d427b66a
JB
418#include <sys/types.h>
419#include <stdio.h>
420#include <sys/stat.h>
421#include <memory.h>
d427b66a
JB
422#include <errno.h>
423#include <unistd.h>
424#include <fcntl.h>
cb1ee811 425#if !defined (__NetBSD__) && !defined (__OpenBSD__)
d427b66a 426#include <elf.h>
e5d0f709 427#endif
d427b66a 428#include <sys/mman.h>
9240b21d
RS
429#if defined (__sony_news) && defined (_SYSTYPE_SYSV)
430#include <sys/elf_mips.h>
431#include <sym.h>
432#endif /* __sony_news && _SYSTYPE_SYSV */
bc597cc7 433#if __sgi
52da6a59 434#include <syms.h> /* for HDRR declaration */
bc597cc7 435#endif /* __sgi */
4dbcac31 436
aff37336
SS
437#ifndef MAP_ANON
438#ifdef MAP_ANONYMOUS
439#define MAP_ANON MAP_ANONYMOUS
440#else
441#define MAP_ANON 0
442#endif
443#endif
444
445#ifndef MAP_FAILED
446#define MAP_FAILED ((void *) -1)
447#endif
448
cb1ee811 449#if defined (__alpha__) && !defined (__NetBSD__) && !defined (__OpenBSD__)
eabb24d0
RS
450/* Declare COFF debugging symbol table. This used to be in
451 /usr/include/sym.h, but this file is no longer included in Red Hat
452 5.0 and presumably in any other glibc 2.x based distribution. */
453typedef struct {
454 short magic;
455 short vstamp;
456 int ilineMax;
457 int idnMax;
458 int ipdMax;
459 int isymMax;
460 int ioptMax;
461 int iauxMax;
462 int issMax;
463 int issExtMax;
464 int ifdMax;
465 int crfd;
466 int iextMax;
467 long cbLine;
468 long cbLineOffset;
469 long cbDnOffset;
470 long cbPdOffset;
471 long cbSymOffset;
472 long cbOptOffset;
473 long cbAuxOffset;
474 long cbSsOffset;
475 long cbSsExtOffset;
476 long cbFdOffset;
477 long cbRfdOffset;
478 long cbExtOffset;
7da3d06f 479} HDRR, *pHDRR;
eabb24d0
RS
480#define cbHDRR sizeof(HDRR)
481#define hdrNil ((pHDRR)0)
265b2695
RS
482#endif
483
e5d0f709
RS
484#ifdef __NetBSD__
485/*
486 * NetBSD does not have normal-looking user-land ELF support.
487 */
3af5762e 488# if defined __alpha__ || defined __sparc_v9__
e5d0f709
RS
489# define ELFSIZE 64
490# else
491# define ELFSIZE 32
492# endif
493# include <sys/exec_elf.h>
494
0007072a
KR
495# ifndef PT_LOAD
496# define PT_LOAD Elf_pt_load
f4db570c
GM
497# if 0 /* was in pkgsrc patches for 20.7 */
498# define SHT_PROGBITS Elf_sht_progbits
499# endif
0007072a
KR
500# define SHT_SYMTAB Elf_sht_symtab
501# define SHT_DYNSYM Elf_sht_dynsym
502# define SHT_NULL Elf_sht_null
503# define SHT_NOBITS Elf_sht_nobits
504# define SHT_REL Elf_sht_rel
505# define SHT_RELA Elf_sht_rela
506
507# define SHN_UNDEF Elf_eshn_undefined
508# define SHN_ABS Elf_eshn_absolute
509# define SHN_COMMON Elf_eshn_common
f4db570c 510# endif /* !PT_LOAD */
e5d0f709 511
e5d0f709
RS
512# ifdef __alpha__
513# include <sys/exec_ecoff.h>
514# define HDRR struct ecoff_symhdr
515# define pHDRR HDRR *
f4db570c 516# endif /* __alpha__ */
e5d0f709 517
6b7d4ae4 518#ifdef __mips__ /* was in pkgsrc patches for 20.7 */
f4db570c
GM
519# define SHT_MIPS_DEBUG DT_MIPS_FLAGS
520# define HDRR struct Elf_Shdr
521#endif /* __mips__ */
6b7d4ae4 522#endif /* __NetBSD__ */
f4db570c 523
cb1ee811
RS
524#ifdef __OpenBSD__
525# include <sys/exec_elf.h>
526#endif
527
265b2695
RS
528#if __GNU_LIBRARY__ - 0 >= 6
529# include <link.h> /* get ElfW etc */
530#endif
531
532#ifndef ElfW
533# ifdef __STDC__
1b963cdd 534# define ElfBitsW(bits, type) Elf##bits##_##type
68c45bf0 535# else
1b963cdd 536# define ElfBitsW(bits, type) Elf/**/bits/**/_/**/type
68c45bf0 537# endif
1b963cdd
DL
538# ifdef _LP64
539# define ELFSIZE 64
540# else
541# define ELFSIZE 32
542# endif
543 /* This macro expands `bits' before invoking ElfBitsW. */
544# define ElfExpandBitsW(bits, type) ElfBitsW (bits, type)
545# define ElfW(type) ElfExpandBitsW (ELFSIZE, type)
d427b66a
JB
546#endif
547
d8858cfe
RS
548#ifndef ELF_BSS_SECTION_NAME
549#define ELF_BSS_SECTION_NAME ".bss"
550#endif
551
d427b66a
JB
552/* Get the address of a particular section or program header entry,
553 * accounting for the size of the entries.
554 */
bc597cc7 555/*
ea083293
RS
556 On PPC Reference Platform running Solaris 2.5.1
557 the plt section is also of type NOBI like the bss section.
558 (not really stored) and therefore sections after the bss
559 section start at the plt offset. The plt section is always
560 the one just before the bss section.
561 Thus, we modify the test from
562 if (NEW_SECTION_H (nn).sh_offset >= new_data2_offset)
563 to
bc597cc7 564 if (NEW_SECTION_H (nn).sh_offset >=
ea083293
RS
565 OLD_SECTION_H (old_bss_index-1).sh_offset)
566 This is just a hack. We should put the new data section
567 before the .plt section.
568 And we should not have this routine at all but use
569 the libelf library to read the old file and create the new
570 file.
571 The changed code is minimal and depends on prep set in m/prep.h
572 Erik Deumens
573 Quantum Theory Project
574 University of Florida
575 deumens@qtp.ufl.edu
576 Apr 23, 1996
577 */
d427b66a
JB
578
579#define OLD_SECTION_H(n) \
265b2695 580 (*(ElfW(Shdr) *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
d427b66a 581#define NEW_SECTION_H(n) \
265b2695 582 (*(ElfW(Shdr) *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
d427b66a 583#define OLD_PROGRAM_H(n) \
265b2695 584 (*(ElfW(Phdr) *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
d427b66a 585#define NEW_PROGRAM_H(n) \
265b2695 586 (*(ElfW(Phdr) *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
d427b66a 587
e40c4104
RS
588#define PATCH_INDEX(n) \
589 do { \
d7cb42c3 590 if ((int) (n) >= old_bss_index) \
e40c4104 591 (n)++; } while (0)
d427b66a
JB
592typedef unsigned char byte;
593
e40c4104
RS
594/* Round X up to a multiple of Y. */
595
bc597cc7 596static ElfW(Addr)
e40c4104 597round_up (x, y)
4461bfd3 598 ElfW(Addr) x, y;
e40c4104
RS
599{
600 int rem = x % y;
601 if (rem == 0)
602 return x;
603 return x - rem + y;
604}
605
52da6a59
GM
606/* Return the index of the section named NAME.
607 SECTION_NAMES, FILE_NAME and FILE_H give information
608 about the file we are looking in.
609
610 If we don't find the section NAME, that is a fatal error
611 if NOERROR is 0; we return -1 if NOERROR is nonzero. */
612
613static int
614find_section (name, section_names, file_name, old_file_h, old_section_h, noerror)
615 char *name;
616 char *section_names;
617 char *file_name;
618 ElfW(Ehdr) *old_file_h;
619 ElfW(Shdr) *old_section_h;
620 int noerror;
621{
622 int idx;
623
624 for (idx = 1; idx < old_file_h->e_shnum; idx++)
625 {
626#ifdef DEBUG
627 fprintf (stderr, "Looking for %s - found %s\n", name,
628 section_names + OLD_SECTION_H (idx).sh_name);
629#endif
630 if (!strcmp (section_names + OLD_SECTION_H (idx).sh_name,
631 name))
632 break;
633 }
634 if (idx == old_file_h->e_shnum)
635 {
636 if (noerror)
637 return -1;
638 else
f4db570c 639 fatal ("Can't find %s in %s.\n", name, file_name);
52da6a59
GM
640 }
641
642 return idx;
643}
644
d427b66a
JB
645/* ****************************************************************
646 * unexec
647 *
648 * driving logic.
649 *
650 * In ELF, this works by replacing the old .bss section with a new
651 * .data section, and inserting an empty .bss immediately afterwards.
652 *
653 */
654void
655unexec (new_name, old_name, data_start, bss_start, entry_address)
656 char *new_name, *old_name;
657 unsigned data_start, bss_start, entry_address;
658{
d427b66a
JB
659 int new_file, old_file, new_file_size;
660
d9d54213 661 /* Pointers to the base of the image of the two files. */
d427b66a
JB
662 caddr_t old_base, new_base;
663
aff37336
SS
664#if MAP_ANON == 0
665 int mmap_fd;
666#else
667# define mmap_fd -1
668#endif
669
d9d54213
RS
670 /* Pointers to the file, program and section headers for the old and
671 new files. */
265b2695
RS
672 ElfW(Ehdr) *old_file_h, *new_file_h;
673 ElfW(Phdr) *old_program_h, *new_program_h;
674 ElfW(Shdr) *old_section_h, *new_section_h;
d427b66a 675
d9d54213 676 /* Point to the section name table in the old file. */
d427b66a
JB
677 char *old_section_names;
678
265b2695
RS
679 ElfW(Addr) old_bss_addr, new_bss_addr;
680 ElfW(Word) old_bss_size, new_data2_size;
681 ElfW(Off) new_data2_offset;
682 ElfW(Addr) new_data2_addr;
d427b66a 683
52da6a59 684 int n, nn;
825dad89 685 int old_bss_index, old_sbss_index, old_plt_index;
52da6a59
GM
686 int old_data_index, new_data2_index;
687 int old_mdebug_index;
d427b66a 688 struct stat stat_buf;
86928dfb 689 int old_file_size;
d427b66a 690
6fb8339c 691 /* Open the old file, allocate a buffer of the right size, and read
d9d54213 692 in the file contents. */
d427b66a
JB
693
694 old_file = open (old_name, O_RDONLY);
695
696 if (old_file < 0)
697 fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
698
699 if (fstat (old_file, &stat_buf) == -1)
d7cb42c3 700 fatal ("Can't fstat (%s): errno %d\n", old_name, errno);
d427b66a 701
aff37336
SS
702#if MAP_ANON == 0
703 mmap_fd = open ("/dev/zero", O_RDONLY);
704 if (mmap_fd < 0)
1ec324f3 705 fatal ("Can't open /dev/zero for reading: errno %d\n", errno, 0);
aff37336
SS
706#endif
707
86928dfb
GM
708 /* We cannot use malloc here because that may use sbrk. If it does,
709 we'd dump our temporary buffers with Emacs, and we'd have to be
710 extra careful to use the correct value of sbrk(0) after
711 allocating all buffers in the code below, which we aren't. */
712 old_file_size = stat_buf.st_size;
713 old_base = mmap (NULL, old_file_size, PROT_READ | PROT_WRITE,
aff37336
SS
714 MAP_ANON | MAP_PRIVATE, mmap_fd, 0);
715 if (old_base == MAP_FAILED)
1ec324f3 716 fatal ("Can't allocate buffer for %s\n", old_name, 0);
d427b66a 717
6fb8339c
EZ
718 if (read (old_file, old_base, stat_buf.st_size) != stat_buf.st_size)
719 fatal ("Didn't read all of %s: errno %d\n", old_name, errno);
720
d427b66a
JB
721 /* Get pointers to headers & section names */
722
265b2695
RS
723 old_file_h = (ElfW(Ehdr) *) old_base;
724 old_program_h = (ElfW(Phdr) *) ((byte *) old_base + old_file_h->e_phoff);
725 old_section_h = (ElfW(Shdr) *) ((byte *) old_base + old_file_h->e_shoff);
d427b66a 726 old_section_names = (char *) old_base
d7cb42c3 727 + OLD_SECTION_H (old_file_h->e_shstrndx).sh_offset;
d427b66a 728
52da6a59
GM
729 /* Find the mdebug section, if any. */
730
731 old_mdebug_index = find_section (".mdebug", old_section_names,
732 old_name, old_file_h, old_section_h, 1);
733
d427b66a 734 /* Find the old .bss section. Figure out parameters of the new
d9d54213 735 data2 and bss sections. */
d427b66a 736
52da6a59
GM
737 old_bss_index = find_section (".bss", old_section_names,
738 old_name, old_file_h, old_section_h, 0);
d427b66a 739
52da6a59
GM
740 old_sbss_index = find_section (".sbss", old_section_names,
741 old_name, old_file_h, old_section_h, 1);
1b963cdd 742 if (old_sbss_index != -1)
825dad89 743 if (OLD_SECTION_H (old_sbss_index).sh_type != SHT_NOBITS)
1b963cdd 744 old_sbss_index = -1;
52da6a59 745
825dad89
AS
746 /* PowerPC64 has .plt in the BSS section. */
747 old_plt_index = find_section (".plt", old_section_names,
748 old_name, old_file_h, old_section_h, 1);
749 if (old_plt_index != -1)
750 if (OLD_SECTION_H (old_plt_index).sh_type != SHT_NOBITS)
751 old_plt_index = -1;
752
753 if (old_sbss_index == -1 && old_plt_index == -1)
9240b21d 754 {
52da6a59
GM
755 old_bss_addr = OLD_SECTION_H (old_bss_index).sh_addr;
756 old_bss_size = OLD_SECTION_H (old_bss_index).sh_size;
9240b21d
RS
757 new_data2_index = old_bss_index;
758 }
825dad89
AS
759 else if (old_plt_index != -1
760 && (old_sbss_index == -1
761 || (OLD_SECTION_H (old_sbss_index).sh_addr
762 > OLD_SECTION_H (old_plt_index).sh_addr)))
763 {
764 old_bss_addr = OLD_SECTION_H (old_plt_index).sh_addr;
765 old_bss_size = OLD_SECTION_H (old_bss_index).sh_size
766 + OLD_SECTION_H (old_plt_index).sh_size;
767 if (old_sbss_index != -1)
768 old_bss_size += OLD_SECTION_H (old_sbss_index).sh_size;
769 new_data2_index = old_plt_index;
770 }
9240b21d
RS
771 else
772 {
52da6a59
GM
773 old_bss_addr = OLD_SECTION_H (old_sbss_index).sh_addr;
774 old_bss_size = OLD_SECTION_H (old_bss_index).sh_size
775 + OLD_SECTION_H (old_sbss_index).sh_size;
9240b21d
RS
776 new_data2_index = old_sbss_index;
777 }
778
52da6a59
GM
779 /* Find the old .data section. Figure out parameters of
780 the new data2 and bss sections. */
781
782 old_data_index = find_section (".data", old_section_names,
783 old_name, old_file_h, old_section_h, 0);
bc597cc7 784
cb1ee811 785#if defined (emacs) || !defined (DEBUG)
265b2695 786 new_bss_addr = (ElfW(Addr)) sbrk (0);
d427b66a
JB
787#else
788 new_bss_addr = old_bss_addr + old_bss_size + 0x1234;
789#endif
790 new_data2_addr = old_bss_addr;
791 new_data2_size = new_bss_addr - old_bss_addr;
52da6a59
GM
792 new_data2_offset = OLD_SECTION_H (old_data_index).sh_offset +
793 (new_data2_addr - OLD_SECTION_H (old_data_index).sh_addr);
d427b66a
JB
794
795#ifdef DEBUG
796 fprintf (stderr, "old_bss_index %d\n", old_bss_index);
d283640e
KH
797 fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
798 fprintf (stderr, "old_bss_size %x\n", old_bss_size);
799 fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
800 fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
801 fprintf (stderr, "new_data2_size %x\n", new_data2_size);
802 fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
d427b66a
JB
803#endif
804
d283640e 805 if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
d427b66a
JB
806 fatal (".bss shrank when undumping???\n", 0, 0);
807
6fb8339c 808 /* Set the output file to the right size. Allocate a buffer to hold
d9d54213
RS
809 the image of the new file. Set pointers to various interesting
810 objects. stat_buf still has old_file data. */
d427b66a
JB
811
812 new_file = open (new_name, O_RDWR | O_CREAT, 0666);
813 if (new_file < 0)
d7cb42c3 814 fatal ("Can't creat (%s): errno %d\n", new_name, errno);
d427b66a
JB
815
816 new_file_size = stat_buf.st_size + old_file_h->e_shentsize + new_data2_size;
817
818 if (ftruncate (new_file, new_file_size))
d7cb42c3 819 fatal ("Can't ftruncate (%s): errno %d\n", new_name, errno);
d427b66a 820
86928dfb 821 new_base = mmap (NULL, new_file_size, PROT_READ | PROT_WRITE,
aff37336
SS
822 MAP_ANON | MAP_PRIVATE, mmap_fd, 0);
823 if (new_base == MAP_FAILED)
1ec324f3 824 fatal ("Can't allocate buffer for %s\n", old_name, 0);
6fb8339c 825
265b2695
RS
826 new_file_h = (ElfW(Ehdr) *) new_base;
827 new_program_h = (ElfW(Phdr) *) ((byte *) new_base + old_file_h->e_phoff);
828 new_section_h = (ElfW(Shdr) *)
d427b66a
JB
829 ((byte *) new_base + old_file_h->e_shoff + new_data2_size);
830
831 /* Make our new file, program and section headers as copies of the
d9d54213 832 originals. */
d427b66a
JB
833
834 memcpy (new_file_h, old_file_h, old_file_h->e_ehsize);
835 memcpy (new_program_h, old_program_h,
836 old_file_h->e_phnum * old_file_h->e_phentsize);
e40c4104
RS
837
838 /* Modify the e_shstrndx if necessary. */
839 PATCH_INDEX (new_file_h->e_shstrndx);
d427b66a
JB
840
841 /* Fix up file header. We'll add one section. Section header is
d9d54213 842 further away now. */
d427b66a
JB
843
844 new_file_h->e_shoff += new_data2_size;
845 new_file_h->e_shnum += 1;
846
847#ifdef DEBUG
d283640e 848 fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff);
d427b66a 849 fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum);
d283640e 850 fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff);
d427b66a
JB
851 fprintf (stderr, "New section count %d\n", new_file_h->e_shnum);
852#endif
853
854 /* Fix up a new program header. Extend the writable data segment so
d9d54213
RS
855 that the bss area is covered too. Find that segment by looking
856 for a segment that ends just before the .bss area. Make sure
857 that no segments are above the new .data2. Put a loop at the end
858 to adjust the offset and address of any segment that is above
859 data2, just in case we decide to allow this later. */
d427b66a
JB
860
861 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
862 {
e40c4104 863 /* Compute maximum of all requirements for alignment of section. */
bc597cc7 864 ElfW(Word) alignment = (NEW_PROGRAM_H (n)).p_align;
e40c4104
RS
865 if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment)
866 alignment = OLD_SECTION_H (old_bss_index).sh_addralign;
867
52da6a59 868#ifdef __sgi
bc597cc7
KH
869 /* According to r02kar@x4u2.desy.de (Karsten Kuenne)
870 and oliva@gnu.org (Alexandre Oliva), on IRIX 5.2, we
871 always get "Program segment above .bss" when dumping
872 when the executable doesn't have an sbss section. */
873 if (old_sbss_index != -1)
52da6a59 874#endif /* __sgi */
9240b21d 875 if (NEW_PROGRAM_H (n).p_vaddr + NEW_PROGRAM_H (n).p_filesz
bc597cc7
KH
876 > (old_sbss_index == -1
877 ? old_bss_addr
878 : round_up (old_bss_addr, alignment)))
879 fatal ("Program segment above .bss in %s\n", old_name, 0);
d427b66a 880
d7cb42c3 881 if (NEW_PROGRAM_H (n).p_type == PT_LOAD
e40c4104
RS
882 && (round_up ((NEW_PROGRAM_H (n)).p_vaddr
883 + (NEW_PROGRAM_H (n)).p_filesz,
884 alignment)
885 == round_up (old_bss_addr, alignment)))
d427b66a
JB
886 break;
887 }
888 if (n < 0)
889 fatal ("Couldn't find segment next to .bss in %s\n", old_name, 0);
890
c1937d6a
AS
891 /* Make sure that the size includes any padding before the old .bss
892 section. */
893 NEW_PROGRAM_H (n).p_filesz = new_bss_addr - NEW_PROGRAM_H (n).p_vaddr;
d7cb42c3 894 NEW_PROGRAM_H (n).p_memsz = NEW_PROGRAM_H (n).p_filesz;
d427b66a
JB
895
896#if 0 /* Maybe allow section after data2 - does this ever happen? */
897 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
898 {
d7cb42c3
RS
899 if (NEW_PROGRAM_H (n).p_vaddr
900 && NEW_PROGRAM_H (n).p_vaddr >= new_data2_addr)
901 NEW_PROGRAM_H (n).p_vaddr += new_data2_size - old_bss_size;
d427b66a 902
d7cb42c3
RS
903 if (NEW_PROGRAM_H (n).p_offset >= new_data2_offset)
904 NEW_PROGRAM_H (n).p_offset += new_data2_size;
d427b66a
JB
905 }
906#endif
907
908 /* Fix up section headers based on new .data2 section. Any section
d9d54213
RS
909 whose offset or virtual address is after the new .data2 section
910 gets its value adjusted. .bss size becomes zero and new address
911 is set. data2 section header gets added by copying the existing
912 .data header and modifying the offset, address and size. */
d7cb42c3 913 for (old_data_index = 1; old_data_index < (int) old_file_h->e_shnum;
d427b66a 914 old_data_index++)
d7cb42c3 915 if (!strcmp (old_section_names + OLD_SECTION_H (old_data_index).sh_name,
d427b66a
JB
916 ".data"))
917 break;
918 if (old_data_index == old_file_h->e_shnum)
919 fatal ("Can't find .data in %s.\n", old_name, 0);
920
994a65f3 921 /* Walk through all section headers, insert the new data2 section right
e40c4104 922 before the new bss section. */
d7cb42c3 923 for (n = 1, nn = 1; n < (int) old_file_h->e_shnum; n++, nn++)
d427b66a
JB
924 {
925 caddr_t src;
9240b21d
RS
926 /* If it is (s)bss section, insert the new data2 section before it. */
927 /* new_data2_index is the index of either old_sbss or old_bss, that was
928 chosen as a section for new_data2. */
bc597cc7 929 if (n == new_data2_index)
e40c4104
RS
930 {
931 /* Steal the data section header for this data2 section. */
d7cb42c3 932 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (old_data_index),
e40c4104 933 new_file_h->e_shentsize);
994a65f3 934
d7cb42c3
RS
935 NEW_SECTION_H (nn).sh_addr = new_data2_addr;
936 NEW_SECTION_H (nn).sh_offset = new_data2_offset;
937 NEW_SECTION_H (nn).sh_size = new_data2_size;
e40c4104
RS
938 /* Use the bss section's alignment. This will assure that the
939 new data2 section always be placed in the same spot as the old
940 bss section by any other application. */
d7cb42c3 941 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (n).sh_addralign;
e40c4104
RS
942
943 /* Now copy over what we have in the memory now. */
994a65f3
RM
944 memcpy (NEW_SECTION_H (nn).sh_offset + new_base,
945 (caddr_t) OLD_SECTION_H (n).sh_addr,
e40c4104
RS
946 new_data2_size);
947 nn++;
948 }
994a65f3
RM
949
950 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n),
e40c4104 951 old_file_h->e_shentsize);
7da3d06f 952
9240b21d 953 if (n == old_bss_index
9240b21d
RS
954 /* The new bss and sbss section's size is zero, and its file offset
955 and virtual address should be off by NEW_DATA2_SIZE. */
825dad89 956 || n == old_sbss_index || n == old_plt_index
9240b21d 957 )
e40c4104 958 {
bc597cc7
KH
959 /* NN should be `old_s?bss_index + 1' at this point. */
960 NEW_SECTION_H (nn).sh_offset =
961 NEW_SECTION_H (new_data2_index).sh_offset + new_data2_size;
962 NEW_SECTION_H (nn).sh_addr =
963 NEW_SECTION_H (new_data2_index).sh_addr + new_data2_size;
e40c4104 964 /* Let the new bss section address alignment be the same as the
994a65f3 965 section address alignment followed the old bss section, so
e40c4104 966 this section will be placed in exactly the same place. */
d7cb42c3
RS
967 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (nn).sh_addralign;
968 NEW_SECTION_H (nn).sh_size = 0;
e40c4104 969 }
85b2e0ee
RS
970 else
971 {
ad537856
RS
972 /* Any section that was originally placed after the .bss
973 section should now be off by NEW_DATA2_SIZE. If a
974 section overlaps the .bss section, consider it to be
975 placed after the .bss section. Overlap can occur if the
976 section just before .bss has less-strict alignment; this
977 was observed between .symtab and .bss on Solaris 2.5.1
978 (sparc) with GCC snapshot 960602. */
f2a77c3a 979
ad537856
RS
980 if (NEW_SECTION_H (nn).sh_offset + NEW_SECTION_H (nn).sh_size
981 > new_data2_offset)
85b2e0ee 982 NEW_SECTION_H (nn).sh_offset += new_data2_size;
f2a77c3a 983
85b2e0ee
RS
984 /* Any section that was originally placed after the section
985 header table should now be off by the size of one section
986 header table entry. */
987 if (NEW_SECTION_H (nn).sh_offset > new_file_h->e_shoff)
988 NEW_SECTION_H (nn).sh_offset += new_file_h->e_shentsize;
989 }
990
e40c4104 991 /* If any section hdr refers to the section after the new .data
994a65f3 992 section, make it refer to next one because we have inserted
8917361f 993 a new section in between. */
994a65f3 994
d7cb42c3 995 PATCH_INDEX (NEW_SECTION_H (nn).sh_link);
8917361f
RS
996 /* For symbol tables, info is a symbol table index,
997 so don't change it. */
998 if (NEW_SECTION_H (nn).sh_type != SHT_SYMTAB
999 && NEW_SECTION_H (nn).sh_type != SHT_DYNSYM)
1000 PATCH_INDEX (NEW_SECTION_H (nn).sh_info);
7da3d06f 1001
1b963cdd
DL
1002 if (old_sbss_index != -1)
1003 if (!strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".sbss"))
1004 {
7da3d06f 1005 NEW_SECTION_H (nn).sh_offset =
1b963cdd
DL
1006 round_up (NEW_SECTION_H (nn).sh_offset,
1007 NEW_SECTION_H (nn).sh_addralign);
1008 NEW_SECTION_H (nn).sh_type = SHT_PROGBITS;
1009 }
8917361f
RS
1010
1011 /* Now, start to copy the content of sections. */
d7cb42c3
RS
1012 if (NEW_SECTION_H (nn).sh_type == SHT_NULL
1013 || NEW_SECTION_H (nn).sh_type == SHT_NOBITS)
d427b66a 1014 continue;
994a65f3 1015
e40c4104 1016 /* Write out the sections. .data and .data1 (and data2, called
8917361f
RS
1017 ".data" in the strings table) get copied from the current process
1018 instead of the old file. */
d7cb42c3 1019 if (!strcmp (old_section_names + NEW_SECTION_H (n).sh_name, ".data")
9240b21d
RS
1020 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
1021 ".sdata")
1022 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
1023 ".lit4")
1024 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
1025 ".lit8")
d4e3d7f2
RS
1026 /* The conditional bit below was in Oliva's original code
1027 (1999-08-25) and seems to have been dropped by mistake
1028 subsequently. It prevents a crash at startup under X in
7da3d06f
DL
1029 `IRIX64 6.5 6.5.17m', whether compiled on that relase or
1030 an earlier one. It causes no trouble on the other ELF
1031 platforms I could test (Irix 6.5.15m, Solaris 8, Debian
1032 Potato x86, Debian Woody SPARC); however, it's reported
1033 to cause crashes under some version of GNU/Linux. It's
1034 not yet clear what's changed in that Irix version to
1035 cause the problem, or why the fix sometimes fails under
1036 GNU/Linux. There's probably no good reason to have
1037 something Irix-specific here, but this will have to do
1038 for now. IRIX6_5 is the most specific macro we have to
1039 test. -- fx 2002-10-01
1040
1041 The issue _looks_ as though it's gone away on 6.5.18m,
1042 but maybe it's still lurking, to be triggered by some
1043 change in the binary. It appears to concern the dynamic
1044 loader, but I never got anywhere with an SGI support call
1045 seeking clues. -- fx 2002-11-29. */
d4e3d7f2
RS
1046#ifdef IRIX6_5
1047 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
1048 ".got")
1049#endif
bc597cc7
KH
1050 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
1051 ".sdata1")
d7cb42c3 1052 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
1b963cdd 1053 ".data1")
6108b49c 1054 || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
1b963cdd 1055 ".sbss"))
d7cb42c3 1056 src = (caddr_t) OLD_SECTION_H (n).sh_addr;
d427b66a 1057 else
d7cb42c3 1058 src = old_base + OLD_SECTION_H (n).sh_offset;
994a65f3 1059
d7cb42c3
RS
1060 memcpy (NEW_SECTION_H (nn).sh_offset + new_base, src,
1061 NEW_SECTION_H (nn).sh_size);
e40c4104 1062
265b2695
RS
1063#ifdef __alpha__
1064 /* Update Alpha COFF symbol table: */
1065 if (strcmp (old_section_names + OLD_SECTION_H (n).sh_name, ".mdebug")
1066 == 0)
1067 {
1068 pHDRR symhdr = (pHDRR) (NEW_SECTION_H (nn).sh_offset + new_base);
1069
1070 symhdr->cbLineOffset += new_data2_size;
1071 symhdr->cbDnOffset += new_data2_size;
1072 symhdr->cbPdOffset += new_data2_size;
1073 symhdr->cbSymOffset += new_data2_size;
1074 symhdr->cbOptOffset += new_data2_size;
1075 symhdr->cbAuxOffset += new_data2_size;
1076 symhdr->cbSsOffset += new_data2_size;
1077 symhdr->cbSsExtOffset += new_data2_size;
1078 symhdr->cbFdOffset += new_data2_size;
1079 symhdr->cbRfdOffset += new_data2_size;
1080 symhdr->cbExtOffset += new_data2_size;
1081 }
1082#endif /* __alpha__ */
1083
9240b21d 1084#if defined (__sony_news) && defined (_SYSTYPE_SYSV)
52da6a59 1085 if (NEW_SECTION_H (nn).sh_type == SHT_MIPS_DEBUG
7da3d06f 1086 && old_mdebug_index != -1)
9240b21d 1087 {
7da3d06f 1088 int diff = NEW_SECTION_H(nn).sh_offset
1ec324f3 1089 - OLD_SECTION_H(old_mdebug_index).sh_offset;
9240b21d
RS
1090 HDRR *phdr = (HDRR *)(NEW_SECTION_H (nn).sh_offset + new_base);
1091
1092 if (diff)
1093 {
1094 phdr->cbLineOffset += diff;
1095 phdr->cbDnOffset += diff;
1096 phdr->cbPdOffset += diff;
1097 phdr->cbSymOffset += diff;
1098 phdr->cbOptOffset += diff;
1099 phdr->cbAuxOffset += diff;
1100 phdr->cbSsOffset += diff;
1101 phdr->cbSsExtOffset += diff;
1102 phdr->cbFdOffset += diff;
1103 phdr->cbRfdOffset += diff;
1104 phdr->cbExtOffset += diff;
1105 }
1106 }
1107#endif /* __sony_news && _SYSTYPE_SYSV */
bc597cc7
KH
1108
1109#if __sgi
7da3d06f 1110 /* Adjust the HDRR offsets in .mdebug and copy the
bc597cc7
KH
1111 line data if it's in its usual 'hole' in the object.
1112 Makes the new file debuggable with dbx.
1113 patches up two problems: the absolute file offsets
1114 in the HDRR record of .mdebug (see /usr/include/syms.h), and
1115 the ld bug that gets the line table in a hole in the
1116 elf file rather than in the .mdebug section proper.
1117 David Anderson. davea@sgi.com Jan 16,1994. */
1118 if (n == old_mdebug_index)
1119 {
1120#define MDEBUGADJUST(__ct,__fileaddr) \
1121 if (n_phdrr->__ct > 0) \
1122 { \
1123 n_phdrr->__fileaddr += movement; \
1124 }
1125
1126 HDRR * o_phdrr = (HDRR *)((byte *)old_base + OLD_SECTION_H (n).sh_offset);
1127 HDRR * n_phdrr = (HDRR *)((byte *)new_base + NEW_SECTION_H (nn).sh_offset);
1128 unsigned movement = new_data2_size;
1129
1130 MDEBUGADJUST (idnMax, cbDnOffset);
1131 MDEBUGADJUST (ipdMax, cbPdOffset);
1132 MDEBUGADJUST (isymMax, cbSymOffset);
1133 MDEBUGADJUST (ioptMax, cbOptOffset);
1134 MDEBUGADJUST (iauxMax, cbAuxOffset);
1135 MDEBUGADJUST (issMax, cbSsOffset);
1136 MDEBUGADJUST (issExtMax, cbSsExtOffset);
1137 MDEBUGADJUST (ifdMax, cbFdOffset);
1138 MDEBUGADJUST (crfd, cbRfdOffset);
1139 MDEBUGADJUST (iextMax, cbExtOffset);
1140 /* The Line Section, being possible off in a hole of the object,
1141 requires special handling. */
1142 if (n_phdrr->cbLine > 0)
1143 {
1144 if (o_phdrr->cbLineOffset > (OLD_SECTION_H (n).sh_offset
1145 + OLD_SECTION_H (n).sh_size))
1146 {
1147 /* line data is in a hole in elf. do special copy and adjust
1148 for this ld mistake.
1149 */
1150 n_phdrr->cbLineOffset += movement;
1151
1152 memcpy (n_phdrr->cbLineOffset + new_base,
1153 o_phdrr->cbLineOffset + old_base, n_phdrr->cbLine);
1154 }
1155 else
1156 {
1157 /* somehow line data is in .mdebug as it is supposed to be. */
1158 MDEBUGADJUST (cbLine, cbLineOffset);
1159 }
1160 }
1161 }
1162#endif /* __sgi */
1163
8917361f 1164 /* If it is the symbol table, its st_shndx field needs to be patched. */
d7cb42c3
RS
1165 if (NEW_SECTION_H (nn).sh_type == SHT_SYMTAB
1166 || NEW_SECTION_H (nn).sh_type == SHT_DYNSYM)
e40c4104 1167 {
265b2695 1168 ElfW(Shdr) *spt = &NEW_SECTION_H (nn);
e40c4104 1169 unsigned int num = spt->sh_size / spt->sh_entsize;
265b2695 1170 ElfW(Sym) * sym = (ElfW(Sym) *) (NEW_SECTION_H (nn).sh_offset +
e40c4104
RS
1171 new_base);
1172 for (; num--; sym++)
1173 {
1174 if ((sym->st_shndx == SHN_UNDEF)
1175 || (sym->st_shndx == SHN_ABS)
1176 || (sym->st_shndx == SHN_COMMON))
1177 continue;
994a65f3 1178
d7cb42c3 1179 PATCH_INDEX (sym->st_shndx);
e40c4104
RS
1180 }
1181 }
d427b66a
JB
1182 }
1183
8917361f 1184 /* Update the symbol values of _edata and _end. */
8bf761ce
RS
1185 for (n = new_file_h->e_shnum - 1; n; n--)
1186 {
1187 byte *symnames;
265b2695 1188 ElfW(Sym) *symp, *symendp;
8bf761ce
RS
1189
1190 if (NEW_SECTION_H (n).sh_type != SHT_DYNSYM
1191 && NEW_SECTION_H (n).sh_type != SHT_SYMTAB)
1192 continue;
1193
8c1e9afe
KH
1194 symnames = ((byte *) new_base
1195 + NEW_SECTION_H (NEW_SECTION_H (n).sh_link).sh_offset);
265b2695
RS
1196 symp = (ElfW(Sym) *) (NEW_SECTION_H (n).sh_offset + new_base);
1197 symendp = (ElfW(Sym) *) ((byte *)symp + NEW_SECTION_H (n).sh_size);
8bf761ce
RS
1198
1199 for (; symp < symendp; symp ++)
1200 if (strcmp ((char *) (symnames + symp->st_name), "_end") == 0
2e1ddb87
RS
1201 || strcmp ((char *) (symnames + symp->st_name), "end") == 0
1202 || strcmp ((char *) (symnames + symp->st_name), "_edata") == 0
1203 || strcmp ((char *) (symnames + symp->st_name), "edata") == 0)
8bf761ce
RS
1204 memcpy (&symp->st_value, &new_bss_addr, sizeof (new_bss_addr));
1205 }
1206
48240339
KH
1207 /* This loop seeks out relocation sections for the data section, so
1208 that it can undo relocations performed by the runtime linker. */
1209 for (n = new_file_h->e_shnum - 1; n; n--)
1210 {
265b2695 1211 ElfW(Shdr) section = NEW_SECTION_H (n);
642ffd98
RS
1212
1213 /* Cause a compilation error if anyone uses n instead of nn below. */
1214 struct {int a;} n;
1e7b70b2 1215 (void)n.a; /* Prevent `unused variable' warnings. */
642ffd98 1216
7da3d06f 1217 switch (section.sh_type)
642ffd98
RS
1218 {
1219 default:
1220 break;
1221 case SHT_REL:
1222 case SHT_RELA:
1223 /* This code handles two different size structs, but there should
1224 be no harm in that provided that r_offset is always the first
1225 member. */
1226 nn = section.sh_info;
1227 if (!strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".data")
1228 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1229 ".sdata")
1230 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1231 ".lit4")
1232 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1233 ".lit8")
d4e3d7f2
RS
1234#ifdef IRIX6_5 /* see above */
1235 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1236 ".got")
1237#endif
642ffd98
RS
1238 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1239 ".sdata1")
1240 || !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
1241 ".data1"))
1242 {
1243 ElfW(Addr) offset = (NEW_SECTION_H (nn).sh_addr
1244 - NEW_SECTION_H (nn).sh_offset);
1245 caddr_t reloc = old_base + section.sh_offset, end;
1246 for (end = reloc + section.sh_size; reloc < end;
1247 reloc += section.sh_entsize)
1248 {
1249 ElfW(Addr) addr = ((ElfW(Rel) *) reloc)->r_offset - offset;
265b2695 1250#ifdef __alpha__
642ffd98
RS
1251 /* The Alpha ELF binutils currently have a bug that
1252 sometimes results in relocs that contain all
1253 zeroes. Work around this for now... */
1254 if (((ElfW(Rel) *) reloc)->r_offset == 0)
265b2695
RS
1255 continue;
1256#endif
642ffd98
RS
1257 memcpy (new_base + addr, old_base + addr, sizeof(ElfW(Addr)));
1258 }
1259 }
1260 break;
1261 }
48240339 1262 }
48240339 1263
d9d54213 1264 /* Write out new_file, and free the buffers. */
04f903c0
KH
1265
1266 if (write (new_file, new_base, new_file_size) != new_file_size)
1ec324f3
EZ
1267#ifndef emacs
1268 fatal ("Didn't write %d bytes: errno %d\n",
1269 new_file_size, errno);
1270#else
7da3d06f 1271 fatal ("Didn't write %d bytes to %s: errno %d\n",
6fb8339c 1272 new_file_size, new_base, errno);
1ec324f3 1273#endif
86928dfb
GM
1274 munmap (old_base, old_file_size);
1275 munmap (new_base, new_file_size);
6fb8339c 1276
d9d54213 1277 /* Close the files and make the new file executable. */
d427b66a 1278
aff37336
SS
1279#if MAP_ANON == 0
1280 close (mmap_fd);
1281#endif
1282
d427b66a 1283 if (close (old_file))
d7cb42c3 1284 fatal ("Can't close (%s): errno %d\n", old_name, errno);
d427b66a 1285
d9d54213
RS
1286 if (close (new_file))
1287 fatal ("Can't close (%s): errno %d\n", new_name, errno);
d427b66a
JB
1288
1289 if (stat (new_name, &stat_buf) == -1)
d7cb42c3 1290 fatal ("Can't stat (%s): errno %d\n", new_name, errno);
d427b66a
JB
1291
1292 n = umask (777);
1293 umask (n);
1294 stat_buf.st_mode |= 0111 & ~n;
1295 if (chmod (new_name, stat_buf.st_mode) == -1)
d7cb42c3 1296 fatal ("Can't chmod (%s): errno %d\n", new_name, errno);
d427b66a 1297}
ab5796a9
MB
1298
1299/* arch-tag: e02e1512-95e2-4ef0-bba7-b6bce658f1e3
1300 (do not change this comment) */