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comparison src/unexelfsgi.c @ 367:a4f53d9b3154 r21-1-13

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Import from CVS: tag r21-1-13
author cvs
date Mon, 13 Aug 2007 11:01:07 +0200
parents 8e84bee8ddd0
children cc15677e0335
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366:83d76f480a59 367:a4f53d9b3154
1 /* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992 1 /* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992, 1999, 2000
2 Free Software Foundation, Inc. 2 Free Software Foundation, Inc.
3 3
4 This file is part of XEmacs. 4 This file is part of XEmacs.
5 5
6 XEmacs is free software; you can redistribute it and/or modify it 6 XEmacs is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by the 7 under the terms of the GNU General Public License as published by
8 Free Software Foundation; either version 2, or (at your option) any 8 the Free Software Foundation; either version 2, or (at your option)
9 later version. 9 any later version.
10 10
11 XEmacs is distributed in the hope that it will be useful, but WITHOUT 11 GNU Emacs is distributed in the hope that it will be useful, but
12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 for more details. 14 General Public License for more details.
15 15
16 You should have received a copy of the GNU General Public License 16 You should have received a copy of the GNU General Public License
17 along with XEmacs; see the file COPYING. If not, write to 17 along with GNU Emacs; see the file COPYING. If not, write to the
18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330, 18 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */ 19 Boston, MA 02111-1307, USA.
20 20
21 /* Synched up with: FSF 19.31. */ 21 In other words, you are welcome to use, share and improve this
22 program. You are forbidden to forbid anyone else to use, share and
23 improve what you give them. Help stamp out software-hoarding! */
22 24
23 25
24 /* 26 /*
25 * unexec.c - Convert a running program into an a.out file. 27 * unexec.c - Convert a running program into an a.out file.
26 * 28 *
29 * University of Utah 31 * University of Utah
30 * Date: Tue Mar 2 1982 32 * Date: Tue Mar 2 1982
31 * Modified heavily since then. 33 * Modified heavily since then.
32 * 34 *
33 * Synopsis: 35 * Synopsis:
34 * unexec (new_name, a_name, data_start, bss_start, entry_address) 36 * void
35 * char *new_name, *a_name; 37 * unexec (char *new_name,
36 * unsigned data_start, bss_start, entry_address; 38 * char *old_name,
37 * 39 * uintptr_t data_start,
38 * Takes a snapshot of the program and makes an a.out format file in the 40 * uintptr_t bss_start,
39 * file named by the string argument new_name. 41 * uintptr_t entry_address)
40 * If a_name is non-NULL, the symbol table will be taken from the given file. 42 *
41 * On some machines, an existing a_name file is required. 43 * The basic idea is that we start with an ELF file which contains
42 * 44 * .bss (uninitialized global data) section which is normally not in
43 * The boundaries within the a.out file may be adjusted with the data_start 45 * the file. As we load lisp the variables, which were first set to 0,
44 * and bss_start arguments. Either or both may be given as 0 for defaults. 46 * will change their values. We want to save those changed values into
45 * 47 * another ELF file, which will become a new xemacs image. To do this,
46 * Data_start gives the boundary between the text segment and the data 48 * we need to change several structures in the ELF file.
47 * segment of the program. The text segment can contain shared, read-only 49 *
48 * program code and literal data, while the data segment is always unshared 50 * First of all, we need to change the programm header which tells
49 * and unprotected. Data_start gives the lowest unprotected address. 51 * the linker how to load stuff into memory so that data will come
50 * The value you specify may be rounded down to a suitable boundary 52 * from the file and not from the /dev/zero. To do this, we find the
51 * as required by the machine you are using. 53 * segment, which is marked as loadable (type PT_LOAD) and which
52 * 54 * covers the old .bss section. We will next change the filesz and
53 * Specifying zero for data_start means the boundary between text and data 55 * memsz for that segment to extend over the new data section.
54 * should not be the same as when the program was loaded. 56 *
55 * If NO_REMAP is defined, the argument data_start is ignored and the 57 * Next we have to make sure that section header for the stuff which
56 * segment boundaries are never changed. 58 * used to be uninitialized is changed to be initialized and to come
57 * 59 * from the file. To do this, we change the size and the type of the old
58 * Bss_start indicates how much of the data segment is to be saved in the 60 * .bss section (and all other section of the type SHT_NOBITS) to cover the
59 * a.out file and restored when the program is executed. It gives the lowest 61 * new section and to be of type SHT_PROCBITS.
60 * unsaved address, and is rounded up to a page boundary. The default when 0 62 *
61 * is given assumes that the entire data segment is to be stored, including 63 * We also insert a new SHT_NOBITS section to keep some tools, which expect
62 * the previous data and bss as well as any additional storage allocated with 64 * .bss happy.
63 * break (2). 65 *
64 * 66 * Finally we need to patch up some references to the section
65 * The new file is set up to start at entry_address. 67 * indexes since we change the order and undo the relocation info to
66 * 68 * be the same as it was "before" because we actually used the data
67 * If you make improvements I'd like to get them too. 69 * from the memory which were changed by the run-time linker.
68 * harpo!utah-cs!thomas, thomas@Utah-20
69 *
70 */
71
72 /* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
73 * ELF support added.
74 *
75 * Basic theory: the data space of the running process needs to be
76 * dumped to the output file. Normally we would just enlarge the size
77 * of .data, scooting everything down. But we can't do that in ELF,
78 * because there is often something between the .data space and the
79 * .bss space.
80 *
81 * In the temacs dump below, notice that the Global Offset Table
82 * (.got) and the Dynamic link data (.dynamic) come between .data1 and
83 * .bss. It does not work to overlap .data with these fields.
84 *
85 * The solution is to create a new .data segment. This segment is
86 * filled with data from the current process. Since the contents of
87 * various sections refer to sections by index, the new .data segment
88 * is made the last in the table to avoid changing any existing index.
89
90 * This is an example of how the section headers are changed. "Addr"
91 * is a process virtual address. "Offset" is a file offset.
92
93 raid:/nfs/raid/src/dist-18.56/src> dump -h temacs
94
95 temacs:
96
97 **** SECTION HEADER TABLE ****
98 [No] Type Flags Addr Offset Size Name
99 Link Info Adralgn Entsize
100
101 [1] 1 2 0x80480d4 0xd4 0x13 .interp
102 0 0 0x1 0
103
104 [2] 5 2 0x80480e8 0xe8 0x388 .hash
105 3 0 0x4 0x4
106
107 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
108 4 1 0x4 0x10
109
110 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
111 0 0 0x1 0
112
113 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
114 3 7 0x4 0x8
115
116 [6] 1 6 0x8049348 0x1348 0x3 .init
117 0 0 0x4 0
118
119 [7] 1 6 0x804934c 0x134c 0x680 .plt
120 0 0 0x4 0x4
121
122 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
123 0 0 0x4 0
124
125 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
126 0 0 0x4 0
127
128 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
129 0 0 0x4 0
130
131 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
132 0 0 0x4 0
133
134 [12] 1 3 0x8088330 0x3f330 0x20afc .data
135 0 0 0x4 0
136
137 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
138 0 0 0x4 0
139
140 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
141 0 0 0x4 0x4
142
143 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
144 4 0 0x4 0x8
145
146 [16] 8 3 0x80a98f4 0x608f4 0x449c .bss
147 0 0 0x4 0
148
149 [17] 2 0 0 0x608f4 0x9b90 .symtab
150 18 371 0x4 0x10
151
152 [18] 3 0 0 0x6a484 0x8526 .strtab
153 0 0 0x1 0
154
155 [19] 3 0 0 0x729aa 0x93 .shstrtab
156 0 0 0x1 0
157
158 [20] 1 0 0 0x72a3d 0x68b7 .comment
159 0 0 0x1 0
160
161 raid:/nfs/raid/src/dist-18.56/src> dump -h xemacs
162
163 xemacs:
164
165 **** SECTION HEADER TABLE ****
166 [No] Type Flags Addr Offset Size Name
167 Link Info Adralgn Entsize
168
169 [1] 1 2 0x80480d4 0xd4 0x13 .interp
170 0 0 0x1 0
171
172 [2] 5 2 0x80480e8 0xe8 0x388 .hash
173 3 0 0x4 0x4
174
175 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
176 4 1 0x4 0x10
177
178 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
179 0 0 0x1 0
180
181 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
182 3 7 0x4 0x8
183
184 [6] 1 6 0x8049348 0x1348 0x3 .init
185 0 0 0x4 0
186
187 [7] 1 6 0x804934c 0x134c 0x680 .plt
188 0 0 0x4 0x4
189
190 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
191 0 0 0x4 0
192
193 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
194 0 0 0x4 0
195
196 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
197 0 0 0x4 0
198
199 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
200 0 0 0x4 0
201
202 [12] 1 3 0x8088330 0x3f330 0x20afc .data
203 0 0 0x4 0
204
205 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
206 0 0 0x4 0
207
208 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
209 0 0 0x4 0x4
210
211 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
212 4 0 0x4 0x8
213
214 [16] 8 3 0x80c6800 0x7d800 0 .bss
215 0 0 0x4 0
216
217 [17] 2 0 0 0x7d800 0x9b90 .symtab
218 18 371 0x4 0x10
219
220 [18] 3 0 0 0x87390 0x8526 .strtab
221 0 0 0x1 0
222
223 [19] 3 0 0 0x8f8b6 0x93 .shstrtab
224 0 0 0x1 0
225
226 [20] 1 0 0 0x8f949 0x68b7 .comment
227 0 0 0x1 0
228
229 [21] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
230 0 0 0x4 0
231
232 * This is an example of how the file header is changed. "Shoff" is
233 * the section header offset within the file. Since that table is
234 * after the new .data section, it is moved. "Shnum" is the number of
235 * sections, which we increment.
236 *
237 * "Phoff" is the file offset to the program header. "Phentsize" and
238 * "Shentsz" are the program and section header entries sizes respectively.
239 * These can be larger than the apparent struct sizes.
240
241 raid:/nfs/raid/src/dist-18.56/src> dump -f temacs
242
243 temacs:
244
245 **** ELF HEADER ****
246 Class Data Type Machine Version
247 Entry Phoff Shoff Flags Ehsize
248 Phentsize Phnum Shentsz Shnum Shstrndx
249
250 1 1 2 3 1
251 0x80499cc 0x34 0x792f4 0 0x34
252 0x20 5 0x28 21 19
253
254 raid:/nfs/raid/src/dist-18.56/src> dump -f xemacs
255
256 xemacs:
257
258 **** ELF HEADER ****
259 Class Data Type Machine Version
260 Entry Phoff Shoff Flags Ehsize
261 Phentsize Phnum Shentsz Shnum Shstrndx
262
263 1 1 2 3 1
264 0x80499cc 0x34 0x96200 0 0x34
265 0x20 5 0x28 22 19
266
267 * These are the program headers. "Offset" is the file offset to the
268 * segment. "Vaddr" is the memory load address. "Filesz" is the
269 * segment size as it appears in the file, and "Memsz" is the size in
270 * memory. Below, the third segment is the code and the fourth is the
271 * data: the difference between Filesz and Memsz is .bss
272
273 raid:/nfs/raid/src/dist-18.56/src> dump -o temacs
274
275 temacs:
276 ***** PROGRAM EXECUTION HEADER *****
277 Type Offset Vaddr Paddr
278 Filesz Memsz Flags Align
279
280 6 0x34 0x8048034 0
281 0xa0 0xa0 5 0
282
283 3 0xd4 0 0
284 0x13 0 4 0
285
286 1 0x34 0x8048034 0
287 0x3f2f9 0x3f2f9 5 0x1000
288
289 1 0x3f330 0x8088330 0
290 0x215c4 0x25a60 7 0x1000
291
292 2 0x60874 0x80a9874 0
293 0x80 0 7 0
294
295 raid:/nfs/raid/src/dist-18.56/src> dump -o xemacs
296
297 xemacs:
298 ***** PROGRAM EXECUTION HEADER *****
299 Type Offset Vaddr Paddr
300 Filesz Memsz Flags Align
301
302 6 0x34 0x8048034 0
303 0xa0 0xa0 5 0
304
305 3 0xd4 0 0
306 0x13 0 4 0
307
308 1 0x34 0x8048034 0
309 0x3f2f9 0x3f2f9 5 0x1000
310
311 1 0x3f330 0x8088330 0
312 0x3e4d0 0x3e4d0 7 0x1000
313
314 2 0x60874 0x80a9874 0
315 0x80 0 7 0
316
317
318 */ 70 */
319 71
320 /* Modified by wtien@urbana.mcd.mot.com of Motorola Inc. 72 #ifndef emacs
321 * 73 #define fatal(a, b, c) fprintf (stderr, a, b, c), exit (1)
322 * The above mechanism does not work if the unexeced ELF file is being 74 #include <string.h>
323 * re-layout by other applications (such as `strip'). All the applications 75 #else
324 * that re-layout the internal of ELF will layout all sections in ascending 76 #include <config.h>
325 * order of their file offsets. After the re-layout, the data2 section will 77 extern void fatal (const char *, ...);
326 * still be the LAST section in the section header vector, but its file offset 78 #endif
327 * is now being pushed far away down, and causes part of it not to be mapped 79
328 * in (ie. not covered by the load segment entry in PHDR vector), therefore
329 * causes the new binary to fail.
330 *
331 * The solution is to modify the unexec algorithm to insert the new data2
332 * section header right before the new bss section header, so their file
333 * offsets will be in the ascending order. Since some of the section's (all
334 * sections AFTER the bss section) indexes are now changed, we also need to
335 * modify some fields to make them point to the right sections. This is done
336 * by macro PATCH_INDEX. All the fields that need to be patched are:
337 *
338 * 1. ELF header e_shstrndx field.
339 * 2. section header sh_link and sh_info field.
340 * 3. symbol table entry st_shndx field.
341 *
342 * The above example now should look like:
343
344 **** SECTION HEADER TABLE ****
345 [No] Type Flags Addr Offset Size Name
346 Link Info Adralgn Entsize
347
348 [1] 1 2 0x80480d4 0xd4 0x13 .interp
349 0 0 0x1 0
350
351 [2] 5 2 0x80480e8 0xe8 0x388 .hash
352 3 0 0x4 0x4
353
354 [3] 11 2 0x8048470 0x470 0x7f0 .dynsym
355 4 1 0x4 0x10
356
357 [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
358 0 0 0x1 0
359
360 [5] 9 2 0x8049010 0x1010 0x338 .rel.plt
361 3 7 0x4 0x8
362
363 [6] 1 6 0x8049348 0x1348 0x3 .init
364 0 0 0x4 0
365
366 [7] 1 6 0x804934c 0x134c 0x680 .plt
367 0 0 0x4 0x4
368
369 [8] 1 6 0x80499cc 0x19cc 0x3c56f .text
370 0 0 0x4 0
371
372 [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
373 0 0 0x4 0
374
375 [10] 1 2 0x8085f40 0x3df40 0x69c .rodata
376 0 0 0x4 0
377
378 [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
379 0 0 0x4 0
380
381 [12] 1 3 0x8088330 0x3f330 0x20afc .data
382 0 0 0x4 0
383
384 [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
385 0 0 0x4 0
386
387 [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
388 0 0 0x4 0x4
389
390 [15] 6 3 0x80a9874 0x60874 0x80 .dynamic
391 4 0 0x4 0x8
392
393 [16] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
394 0 0 0x4 0
395
396 [17] 8 3 0x80c6800 0x7d800 0 .bss
397 0 0 0x4 0
398
399 [18] 2 0 0 0x7d800 0x9b90 .symtab
400 19 371 0x4 0x10
401
402 [19] 3 0 0 0x87390 0x8526 .strtab
403 0 0 0x1 0
404
405 [20] 3 0 0 0x8f8b6 0x93 .shstrtab
406 0 0 0x1 0
407
408 [21] 1 0 0 0x8f949 0x68b7 .comment
409 0 0 0x1 0
410
411 */
412
413 /* More mods, by Jack Repenning <jackr@sgi.com>, Fri Aug 11 15:45:52 1995
414
415 Same algorithm as immediately above. However, the detailed
416 calculations of the various locations needed significant
417 overhaul.
418
419 At the point of the old .bss, the file offsets and the memory
420 addresses do distinct, slightly snaky things:
421
422 offset of .bss is meaningless and unpredictable
423 addr of .bss is meaningful
424 alignment of .bss is important to addr, so there may be a small
425 gap in address range before start of bss
426 offset of next section is rounded up modulo 0x1000
427 the hole so-introduced is zero-filled, so it can be mapped in as
428 the first partial-page of bss (the rest of the bss is mapped from
429 /dev/zero)
430 I suppose you could view this not as a hole, but as the beginning
431 of the bss, actually present in the file. But you should not
432 push that worldview too far, as the linker still knows that the
433 "offset" claimed for the bss is unused, and seems not always
434 careful about setting it.
435
436 We are doing all our tricks at this same rather complicated
437 location (isn't life fun?):
438
439 insert a new data section to contain now-initialized old bss and
440 heap
441 define a zero-length bss just so there is one
442
443 The offset of the new data section is dictated by its current
444 address (which, of course, we want also to be its addr): the
445 loader maps in the whole file region containing old data, rodata,
446 got, and new data as a single mapped segment, starting at the
447 address of the first chunk; the rest have to be laid out in the
448 file such that the map into the right spots. That is:
449
450 offset(newdata) ==
451 addrInRunningMemory(newdata)-aIRM(olddata)
452 + offset(oldData)
453
454 This would not necessarily match the oldbss offset, even if it
455 were carefully calculated! We must compute this.
456
457 The linker that built temacs has also already arranged that
458 olddata is properly page-aligned (not necessarily beginning on a
459 page, but rather that a page's worth of the low bits of addr and
460 offset match). We preserve this.
461
462 addr(bss) is alignment-constrained from the end of the new data.
463 Since we base endof(newdata) on sbrk(), we have a page boundary
464 (in both offset and addr) and meet any alignment constraint,
465 needing no alignment adjustment of this location and no
466 mini-hole. Or, if you like, we've allowed sbrk() to "compute"
467 the mini-hole size for us.
468
469 That puts newbss beginning on a page boundary, both in offset and
470 addr. (offset(bss) is still meaningless, but what the heck,
471 we'll fix it up.)
472
473 Since newbss has zero length, and its offset (however
474 meaningless) is page aligned, we place the next section exactly
475 there, with no hole needed to restore page alignment.
476
477 So, the shift for all sections beyond the playing field is:
478
479 new_bss_addr - roundup(old_bss_addr,0x1000)
480
481 */
482 /* Still more mods... Olivier Galibert 19971705
483 - support for .sbss section (automagically changed to data without
484 name change)
485 - support for 64bits ABI (will need a bunch of fixes in the rest
486 of the code before it works
487 */
488
489 #include <sys/types.h> 80 #include <sys/types.h>
490 #include <stdio.h> 81 #include <stdio.h>
491 #include <sys/stat.h> 82 #include <sys/stat.h>
492 #include <memory.h> 83 #include <memory.h>
493 #include <string.h>
494 #include <errno.h> 84 #include <errno.h>
495 #include <unistd.h> 85 #include <unistd.h>
496 #include <fcntl.h> 86 #include <fcntl.h>
497 #include <elf.h> 87 #include <elf.h>
498 #include <sym.h> /* for HDRR declaration */
499 #include <sys/mman.h> 88 #include <sys/mman.h>
500 #include <config.h> 89 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
501 #include "lisp.h" 90 #include <sys/elf_mips.h>
502 91 #include <sym.h>
503 /* in 64bits mode, use 64bits elf */ 92 #endif /* __sony_news && _SYSTYPE_SYSV */
504 #ifdef _ABI64 93 #if __sgi
505 typedef Elf64_Shdr l_Elf_Shdr; 94 #include <syms.h> /* for HDRR declaration */
506 typedef Elf64_Phdr l_Elf_Phdr; 95 #endif /* __sgi */
507 typedef Elf64_Ehdr l_Elf_Ehdr; 96
508 typedef Elf64_Addr l_Elf_Addr; 97 #if __GNU_LIBRARY__ - 0 >= 6
509 typedef Elf64_Word l_Elf_Word; 98 # include <link.h> /* get ElfW etc */
510 typedef Elf64_Off l_Elf_Off; 99 #endif
511 typedef Elf64_Sym l_Elf_Sym; 100
512 #else 101 #ifndef ElfW
513 typedef Elf32_Shdr l_Elf_Shdr; 102 # ifdef __STDC__
514 typedef Elf32_Phdr l_Elf_Phdr; 103 # define ElfBitsW(bits, type) Elf##bits##_##type
515 typedef Elf32_Ehdr l_Elf_Ehdr; 104 # else
516 typedef Elf32_Addr l_Elf_Addr; 105 # define ElfBitsW(bits, type) Elf/**/bits/**/_/**/type
517 typedef Elf32_Word l_Elf_Word; 106 # endif
518 typedef Elf32_Off l_Elf_Off; 107 # ifdef _LP64
519 typedef Elf32_Sym l_Elf_Sym; 108 # define ELFSIZE 64
520 #endif 109 # else
521 110 # define ELFSIZE 32
111 # endif
112 /* This macro expands `bits' before invoking ElfBitsW. */
113 # define ElfExpandBitsW(bits, type) ElfBitsW (bits, type)
114 # define ElfW(type) ElfExpandBitsW (ELFSIZE, type)
115 #endif
116
117 #ifndef ELF_BSS_SECTION_NAME
118 #define ELF_BSS_SECTION_NAME ".bss"
119 #endif
522 120
523 /* Get the address of a particular section or program header entry, 121 /* Get the address of a particular section or program header entry,
524 * accounting for the size of the entries. 122 * accounting for the size of the entries. */
525 */
526 123
527 #define OLD_SECTION_H(n) \ 124 #define OLD_SECTION_H(n) \
528 (*(l_Elf_Shdr *) ((byte *) old_section_h + old_file_h->e_shentsize * (n))) 125 (*(ElfW(Shdr) *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
529 #define NEW_SECTION_H(n) \ 126 #define NEW_SECTION_H(n) \
530 (*(l_Elf_Shdr *) ((byte *) new_section_h + new_file_h->e_shentsize * (n))) 127 (*(ElfW(Shdr) *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
531 #define OLD_PROGRAM_H(n) \ 128 #define OLD_PROGRAM_H(n) \
532 (*(l_Elf_Phdr *) ((byte *) old_program_h + old_file_h->e_phentsize * (n))) 129 (*(ElfW(Phdr) *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
533 #define NEW_PROGRAM_H(n) \ 130 #define NEW_PROGRAM_H(n) \
534 (*(l_Elf_Phdr *) ((byte *) new_program_h + new_file_h->e_phentsize * (n))) 131 (*(ElfW(Phdr) *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
535 132
536 #define PATCH_INDEX(n) \ 133 #define PATCH_INDEX(n) \
537 do { \ 134 do { \
538 if ((n) >= old_bss_index) \ 135 if ((int) (n) >= growme_index) \
539 (n)++; } while (0) 136 (n)++; } while (0)
137
540 typedef unsigned char byte; 138 typedef unsigned char byte;
541 139
542 /* Round X up to a multiple of Y. */ 140 /* Round X up to a multiple of Y. */
543 141
544 int 142 static ElfW(Addr)
545 round_up (x, y) 143 round_up (ElfW(Addr) x, ElfW(Addr) y)
546 int x, y;
547 { 144 {
548 int rem = x % y; 145 int rem = x % y;
549 if (rem == 0) 146 if (rem == 0)
550 return x; 147 return x;
551 return x - rem + y; 148 return x - rem + y;
557 154
558 If we don't find the section NAME, that is a fatal error 155 If we don't find the section NAME, that is a fatal error
559 if NOERROR is 0; we return -1 if NOERROR is nonzero. */ 156 if NOERROR is 0; we return -1 if NOERROR is nonzero. */
560 157
561 static int 158 static int
562 find_section (name, section_names, file_name, old_file_h, old_section_h, noerror) 159 find_section (char *name,
563 char *name; 160 const char *section_names,
564 char *section_names; 161 char *file_name,
565 char *file_name; 162 ElfW(Ehdr) *old_file_h,
566 l_Elf_Ehdr *old_file_h; 163 ElfW(Shdr) *old_section_h,
567 l_Elf_Shdr *old_section_h; 164 int noerror)
568 int noerror;
569 { 165 {
570 int idx; 166 int idx;
571 167
572 for (idx = 1; idx < old_file_h->e_shnum; idx++) 168 for (idx = 1; idx < old_file_h->e_shnum; idx++)
573 { 169 {
575 fprintf (stderr, "Looking for %s - found %s\n", name, 171 fprintf (stderr, "Looking for %s - found %s\n", name,
576 section_names + OLD_SECTION_H (idx).sh_name); 172 section_names + OLD_SECTION_H (idx).sh_name);
577 #endif 173 #endif
578 if (!strcmp (section_names + OLD_SECTION_H (idx).sh_name, 174 if (!strcmp (section_names + OLD_SECTION_H (idx).sh_name,
579 name)) 175 name))
580 break; 176 return idx;
581 } 177 }
582 if (idx == old_file_h->e_shnum) 178
583 { 179 /* If we're here, we found nothing or return did not work */
584 if (noerror) 180 if ( ! noerror)
585 return -1; 181 fatal ("Can't find %s in %s.\n", name, file_name);
586 else 182
587 fatal ("Can't find .bss in %s.\n", file_name); 183 return -1;
588 }
589
590 return idx;
591 } 184 }
592 185
593 /* **************************************************************** 186 /* ****************************************************************
594 * unexec 187 * unexec
595 * 188 *
597 * 190 *
598 * In ELF, this works by replacing the old .bss section with a new 191 * In ELF, this works by replacing the old .bss section with a new
599 * .data section, and inserting an empty .bss immediately afterwards. 192 * .data section, and inserting an empty .bss immediately afterwards.
600 * 193 *
601 */ 194 */
602 int 195 void
603 unexec (new_name, old_name, data_start, bss_start, entry_address) 196 unexec (char *new_name,
604 char *new_name, *old_name; 197 char *old_name,
605 uintptr_t data_start, bss_start, entry_address; 198 uintptr_t data_start,
199 uintptr_t bss_start,
200 uintptr_t entry_address)
606 { 201 {
607 extern uintptr_t bss_end; 202 int old_file;
608 int new_file, old_file, new_file_size; 203
609 204 struct stat stat_buf;
610 /* Pointers to the base of the image of the two files. */
611 caddr_t old_base, new_base; 205 caddr_t old_base, new_base;
612 206
613 /* Pointers to the file, program and section headers for the old and new 207 ElfW(Ehdr) *old_file_h, * new_file_h;
614 files. */ 208 ElfW(Phdr) *old_program_h, * new_program_h;
615 l_Elf_Ehdr *old_file_h, *new_file_h; 209 ElfW(Shdr) *old_section_h, * new_section_h;
616 l_Elf_Phdr *old_program_h, *new_program_h; 210 ElfW(Shdr) * growme = NULL, * grown = NULL;
617 l_Elf_Shdr *old_section_h, *new_section_h; 211 ElfW(Addr) old_bss_addr = 0, new_data2_addr = 0;
618 l_Elf_Shdr *oldbss; 212
619 213 int growme_index = -1;
620 /* Point to the section name table in the old file. */ 214 int n, nn;
621 char *old_section_names; 215 const char *old_section_names;
622 216 int old_mdebug_index, old_data_index;
623 l_Elf_Addr old_bss_addr, new_bss_addr; 217 int new_bss_addr, new_data2_size, new_data2_offset, new_file, new_file_size;
624 l_Elf_Addr old_base_addr; 218
625 l_Elf_Word old_bss_size, new_data2_size; 219 /* Open the old file */
626 l_Elf_Off new_data2_offset, new_base_offset; 220 if ( (old_file = open (old_name, O_RDONLY)) < 0 )
627 l_Elf_Addr new_data2_addr; 221 fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
628 l_Elf_Addr new_offsets_shift;
629
630 int n, nn, old_bss_index, old_data_index;
631 int old_mdebug_index, old_sbss_index;
632 struct stat stat_buf;
633
634 /* Open the old file & map it into the address space. */
635
636 old_file = open (old_name, O_RDONLY);
637
638 if (old_file < 0)
639 fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
640 222
641 if (fstat (old_file, &stat_buf) == -1) 223 if (fstat (old_file, &stat_buf) == -1)
642 fatal ("Can't fstat(%s): errno %d\n", old_name, errno); 224 fatal ("Can't fstat (%s): errno %d\n", old_name, errno);
643 225
644 old_base = mmap (0, stat_buf.st_size, PROT_READ, MAP_SHARED, old_file, 0); 226 /* map old file into the address space. */
645 227 old_base = (caddr_t) mmap ((caddr_t) 0, stat_buf.st_size,
646 if (old_base == (caddr_t) -1) 228 PROT_READ, MAP_SHARED, old_file, 0);
647 fatal ("Can't mmap(%s): errno %d\n", old_name, errno); 229 if (old_base == (caddr_t) MAP_FAILED)
648 230 fatal ("Can't mmap (%s): errno %d\n", old_name, errno);
649 #ifdef DEBUG 231
650 fprintf (stderr, "mmap(%s, %x) -> %x\n", old_name, stat_buf.st_size, 232 old_file_h = (ElfW(Ehdr) *) old_base;
651 old_base); 233 old_program_h = (ElfW(Phdr) *) ((byte *) old_base + old_file_h->e_phoff);
652 #endif 234 old_section_h = (ElfW(Shdr) *) ((byte *) old_base + old_file_h->e_shoff);
653 235 old_section_names = (const char *) old_base
654 /* Get pointers to headers & section names. */ 236 + OLD_SECTION_H (old_file_h->e_shstrndx).sh_offset;
655 237
656 old_file_h = (l_Elf_Ehdr *) old_base; 238 /* Find a section which we will grow by looking for the SHT_NOBITS
657 old_program_h = (l_Elf_Phdr *) ((byte *) old_base + old_file_h->e_phoff); 239 * section with ALLOCATE flag and with the biggest address. */
658 old_section_h = (l_Elf_Shdr *) ((byte *) old_base + old_file_h->e_shoff); 240 for (n = 1; n < old_file_h->e_shnum; n++) {
659 old_section_names 241 ElfW(Shdr) * sh = & OLD_SECTION_H(n);
660 = (char *) old_base + OLD_SECTION_H (old_file_h->e_shstrndx).sh_offset; 242
661 243 if ((sh->sh_type == SHT_NOBITS) && (sh->sh_flags & SHF_ALLOC)) {
662 /* Find the mdebug section, if any. */ 244 if ( old_bss_addr < sh->sh_addr ) {
663 245 growme = sh;
664 old_mdebug_index = find_section (".mdebug", old_section_names, 246 growme_index = n;
665 old_name, old_file_h, old_section_h, 1); 247 new_data2_addr = old_bss_addr = sh->sh_addr;
666 248 }
667 /* Find the .sbss section, if any. */ 249 }
668 250 }
669 old_sbss_index = find_section (".sbss", old_section_names, 251
670 old_name, old_file_h, old_section_h, 1); 252 if (growme == NULL )
671 253 fatal ("Can't find a section to grow\n", 0, 0);
672 if (old_sbss_index != -1 && (OLD_SECTION_H (old_sbss_index).sh_type == SHT_PROGBITS))
673 old_sbss_index = -1;
674
675 /* Find the old .bss section. */
676
677 old_bss_index = find_section (".bss", old_section_names,
678 old_name, old_file_h, old_section_h, 0);
679
680 /* Find the old .data section. Figure out parameters of
681 the new data2 and bss sections. */
682 254
683 old_data_index = find_section (".data", old_section_names, 255 old_data_index = find_section (".data", old_section_names,
684 old_name, old_file_h, old_section_h, 0); 256 old_name, old_file_h, old_section_h, 0);
685 257
686 old_bss_addr = OLD_SECTION_H (old_bss_index).sh_addr; 258 new_bss_addr = (ElfW(Addr)) sbrk (0);
687 old_bss_size = OLD_SECTION_H (old_bss_index).sh_size; 259 new_data2_size = new_bss_addr - old_bss_addr;
688 old_base_addr = old_sbss_index == -1 ? old_bss_addr : OLD_SECTION_H (old_sbss_index).sh_addr; 260 new_data2_offset = OLD_SECTION_H (old_data_index).sh_offset +
689 #if defined(emacs) || !defined(DEBUG) 261 (new_data2_addr - OLD_SECTION_H (old_data_index).sh_addr);
690 bss_end = (uintptr_t) sbrk (0); 262
691 new_bss_addr = (l_Elf_Addr) bss_end; 263 if ( new_bss_addr < old_bss_addr + growme->sh_size )
264 fatal (".bss shrank when undumping???\n", 0, 0);
265
266 /* Set the output file to the right size and mmap it. */
267 if ( (new_file = open (new_name, O_RDWR | O_CREAT, 0666)) < 0 )
268 fatal ("Can't create (%s): errno %d\n", new_name, errno);
269
270 new_file_size = stat_buf.st_size + old_file_h->e_shentsize + new_data2_size;
271
272 if (ftruncate (new_file, new_file_size))
273 fatal ("Can't ftruncate (%s): errno %d\n", new_name, errno);
274
275 new_base = (caddr_t) mmap ((caddr_t) 0, new_file_size,
276 PROT_READ | PROT_WRITE,
277 #ifdef UNEXEC_USE_MAP_PRIVATE
278 MAP_PRIVATE,
692 #else 279 #else
693 new_bss_addr = old_bss_addr + old_bss_size + 0x1234; 280 MAP_SHARED,
694 #endif 281 #endif
695 new_data2_addr = old_bss_addr; 282 new_file, 0);
696 new_data2_size = new_bss_addr - old_bss_addr;
697 new_data2_offset = OLD_SECTION_H (old_data_index).sh_offset +
698 (new_data2_addr - OLD_SECTION_H (old_data_index).sh_addr);
699 new_base_offset = OLD_SECTION_H (old_data_index).sh_offset +
700 (old_base_addr - OLD_SECTION_H (old_data_index).sh_addr);
701 new_offsets_shift = new_bss_addr - (old_base_addr & ~0xfff) +
702 ((old_base_addr & 0xfff) ? 0x1000 : 0);
703
704 #ifdef DEBUG
705 fprintf (stderr, "old_bss_index %d\n", old_bss_index);
706 fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
707 fprintf (stderr, "old_bss_size %x\n", old_bss_size);
708 fprintf (stderr, "old_base_addr %x\n", old_base_addr);
709 fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
710 fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
711 fprintf (stderr, "new_data2_size %x\n", new_data2_size);
712 fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
713 fprintf (stderr, "new_offsets_shift %x\n", new_offsets_shift);
714 #endif
715
716 if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
717 fatal (".bss shrank when undumping???\n");
718
719 /* Set the output file to the right size and mmap it. Set
720 pointers to various interesting objects. stat_buf still has
721 old_file data. */
722
723 new_file = open (new_name, O_RDWR | O_CREAT, 0666);
724 if (new_file < 0)
725 fatal ("Can't creat (%s): errno %d\n", new_name, errno);
726
727 new_file_size = stat_buf.st_size /* old file size */
728 + old_file_h->e_shentsize /* one new section header */
729 + new_offsets_shift; /* trailing section shift */
730
731 if (ftruncate (new_file, new_file_size))
732 fatal ("Can't ftruncate (%s): errno %d\n", new_name, errno);
733
734 new_base = mmap (0, new_file_size, PROT_READ | PROT_WRITE, MAP_SHARED,
735 new_file, 0);
736 283
737 if (new_base == (caddr_t) -1) 284 if (new_base == (caddr_t) -1)
738 fatal ("Can't mmap (%s): errno %d\n", new_name, errno); 285 fatal ("Can't mmap (%s): errno %d\n", new_name, errno);
739 286
740 new_file_h = (l_Elf_Ehdr *) new_base; 287 new_file_h = (ElfW(Ehdr) *) new_base;
741 new_program_h = (l_Elf_Phdr *) ((byte *) new_base + old_file_h->e_phoff); 288 new_program_h = (ElfW(Phdr) *) ((byte *) new_base + old_file_h->e_phoff);
742 new_section_h 289 new_section_h = (ElfW(Shdr) *) ((byte *) new_base + old_file_h->e_shoff +
743 = (l_Elf_Shdr *) ((byte *) new_base + old_file_h->e_shoff 290 new_data2_size);
744 + new_offsets_shift);
745 291
746 /* Make our new file, program and section headers as copies of the 292 /* Make our new file, program and section headers as copies of the
747 originals. */ 293 * originals. */
748
749 memcpy (new_file_h, old_file_h, old_file_h->e_ehsize); 294 memcpy (new_file_h, old_file_h, old_file_h->e_ehsize);
750 memcpy (new_program_h, old_program_h, 295 memcpy (new_program_h, old_program_h,
751 old_file_h->e_phnum * old_file_h->e_phentsize); 296 old_file_h->e_phnum * old_file_h->e_phentsize);
752 297
753 /* Modify the e_shstrndx if necessary. */ 298 /* Modify the e_shstrndx if necessary. */
754 PATCH_INDEX (new_file_h->e_shstrndx); 299 PATCH_INDEX (new_file_h->e_shstrndx);
755 300
756 /* Fix up file header. We'll add one section. Section header is 301 /* Fix up file header. We'll add one section. Section header is
757 further away now. */ 302 * further away now. */
758 303 new_file_h->e_shoff += new_data2_size;
759 new_file_h->e_shoff += new_offsets_shift;
760 new_file_h->e_shnum += 1; 304 new_file_h->e_shnum += 1;
761 305
762 306 /* Fix up a new program header by extending the writable data
763 #ifdef DEBUG 307 * segment so that the bss area is covered too. Find that segment by
764 fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff); 308 * looking for one that starts before and ends after the .bss and is
765 fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum); 309 * PT_LOADable. */
766 fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff); 310 for (n = new_file_h->e_phnum - 1; n >= 0; n--) {
767 fprintf (stderr, "New section count %d\n", new_file_h->e_shnum); 311 ElfW(Phdr) * ph = & NEW_PROGRAM_H(n);
768 #endif
769
770 /* Fix up a new program header. Extend the writable data segment so
771 that the bss area is covered too. Find that segment by looking
772 for one that starts before and ends after the .bss and it PT_LOADable.
773 Put a loop at the end to adjust the offset and address of any segment
774 that is above data2, just in case we decide to allow this later. */
775
776 oldbss = &OLD_SECTION_H(old_bss_index);
777 for (n = new_file_h->e_phnum - 1; n >= 0; n--)
778 {
779 /* Compute maximum of all requirements for alignment of section. */
780 l_Elf_Phdr * ph = (l_Elf_Phdr *)((byte *) new_program_h +
781 new_file_h->e_phentsize*(n));
782 #ifdef DEBUG 312 #ifdef DEBUG
783 printf ("%d @ %0x + %0x against %0x + %0x", 313 printf ("%d @ %0x + %0x against %0x + %0x",
784 n, ph->p_vaddr, ph->p_memsz, 314 n, ph->p_vaddr, ph->p_memsz,growme->sh_addr, growme->sh_size);
785 oldbss->sh_addr, oldbss->sh_size); 315 #endif
786 #endif 316 if ((ph->p_type == PT_LOAD) &&
787 if ((ph->p_type == PT_LOAD) && 317 (ph->p_vaddr <= growme->sh_addr) &&
788 (ph->p_vaddr <= oldbss->sh_addr) && 318 ((ph->p_vaddr+ph->p_memsz) >= (growme->sh_addr + growme->sh_size))) {
789 ((ph->p_vaddr + ph->p_memsz)>=(oldbss->sh_addr + oldbss->sh_size))) { 319 /* Make sure that the size includes any padding before the
790 ph->p_filesz += new_offsets_shift; 320 * old .bss section. */
791 ph->p_memsz = ph->p_filesz; 321 ph->p_memsz = ph->p_filesz = new_bss_addr - ph->p_vaddr;
792 #ifdef DEBUG 322 #ifdef DEBUG
793 puts (" That's the one!"); 323 puts (" That's the one!");
794 fflush (stdout); 324 #endif
795 #endif 325 break;
796 break;
797 } 326 }
798 #ifdef DEBUG 327 #ifdef DEBUG
799 putchar ('\n'); 328 putchar ('\n');
800 fflush (stdout); 329 #endif
801 #endif 330 }
802 } 331
803 if (n < 0) 332 if (n < 0)
804 fatal ("Couldn't find segment next to %s in %s\n", 333 fatal ("Couldn't find segment which covers %s",
805 old_sbss_index == -1 ? ".sbss" : ".bss", old_name); 334 old_section_names + growme->sh_name);
806 335
807 336 /* Walk through all section headers, insert the new data2 section
808 #if 1 /* Maybe allow section after data2 - does this ever happen? */ 337 * right before the new bss section. */
809 for (n = new_file_h->e_phnum - 1; n >= 0; n--) 338 for (n = 1, nn = 1; n < (int) old_file_h->e_shnum; n++, nn++) {
810 { 339 ElfW(Shdr) * nsec = & NEW_SECTION_H(nn);
811 if (NEW_PROGRAM_H (n).p_vaddr 340 ElfW(Shdr) * osec = & OLD_SECTION_H(n);
812 && NEW_PROGRAM_H (n).p_vaddr >= new_data2_addr) 341
813 NEW_PROGRAM_H (n).p_vaddr += new_offsets_shift - old_bss_size; 342 /* If this is the section we want to grow, insert the new data
814 343 * section before it. */
815 if (NEW_PROGRAM_H (n).p_offset >= new_data2_offset) 344 if ( osec == growme ) {
816 NEW_PROGRAM_H (n).p_offset += new_offsets_shift; 345 /* Steal the data section header for this data2 section but
817 } 346 * use the * 'grow' section's alignment. This * will assure
818 #endif 347 * that the new section * always be placed in the same spot
819 348 * * as the old section by any other * application. */
820 /* Fix up section headers based on new .data2 section. Any section 349 ElfW(Shdr) * od = &OLD_SECTION_H(old_data_index);
821 whose offset or virtual address is after the new .data2 section 350
822 gets its value adjusted. .bss size becomes zero and new address 351 memcpy (nsec, od, new_file_h->e_shentsize);
823 is set. data2 section header gets added by copying the existing 352
824 .data header and modifying the offset, address and size. */ 353 nsec->sh_addr = new_data2_addr;
825 for (old_data_index = 1; old_data_index < old_file_h->e_shnum; 354 nsec->sh_offset = new_data2_offset;
826 old_data_index++) 355 nsec->sh_size = new_data2_size;
827 if (!strcmp (old_section_names + OLD_SECTION_H (old_data_index).sh_name, 356 nsec->sh_addralign = osec->sh_addralign;
828 ".data")) 357
829 break; 358 /* Copy over what we have in memory now. */
830 if (old_data_index == old_file_h->e_shnum) 359 memcpy (nsec->sh_offset + new_base, (caddr_t) osec->sh_addr,
831 fatal ("Can't find .data in %s.\n", old_name);
832
833 /* Walk through all section headers, insert the new data2 section right
834 before the new bss section. */
835 for (n = 1, nn = 1; n < old_file_h->e_shnum; n++, nn++)
836 {
837 caddr_t src;
838
839 /* XEmacs change: */
840 if (n < old_bss_index)
841 {
842 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n),
843 old_file_h->e_shentsize);
844
845 }
846 else if (n == old_bss_index)
847 {
848
849 /* If it is bss section, insert the new data2 section before it. */
850 /* Steal the data section header for this data2 section. */
851 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (old_data_index),
852 new_file_h->e_shentsize);
853
854 NEW_SECTION_H (nn).sh_addr = new_data2_addr;
855 NEW_SECTION_H (nn).sh_offset = new_data2_offset;
856 NEW_SECTION_H (nn).sh_size = new_data2_size;
857 /* Use the bss section's alignment. This will assure that the
858 new data2 section always be placed in the same spot as the old
859 bss section by any other application. */
860 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (n).sh_addralign;
861
862 /* Now copy over what we have in the memory now. */
863 memcpy (NEW_SECTION_H (nn).sh_offset + new_base,
864 (caddr_t) OLD_SECTION_H (n).sh_addr,
865 new_data2_size); 360 new_data2_size);
866 nn++; 361 nn++;
867 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n), 362 grown = nsec++;
868 old_file_h->e_shentsize); 363 }
869 364
870 /* The new bss section's size is zero, and its file offset and virtual 365 memcpy (nsec, osec, old_file_h->e_shentsize);
871 address should be off by NEW_OFFSETS_SHIFT. */ 366
872 NEW_SECTION_H (nn).sh_offset += new_offsets_shift; 367 if ( osec == growme ) {
873 NEW_SECTION_H (nn).sh_addr = new_bss_addr; 368 /* The new bss section's size is zero, and its file offset
874 /* Let the new bss section address alignment be the same as the 369 * and virtual address should be off by NEW_DATA2_SIZE. */
875 section address alignment followed the old bss section, so 370 nsec->sh_offset = grown->sh_offset + new_data2_size;
876 this section will be placed in exactly the same place. */ 371 nsec->sh_addr = grown->sh_addr + new_data2_size;
877 NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (n).sh_addralign; 372
878 NEW_SECTION_H (nn).sh_size = 0; 373 /* Let the new bss section address alignment be the same as
879 } 374 * the section address alignment followed the old bss
880 else /* n > old_bss_index */ 375 * section, so this section will be placed in exactly the
881 memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n), 376 * same place. */
882 old_file_h->e_shentsize); 377 nsec->sh_addralign = osec->sh_addralign;
883 378 nsec->sh_size = 0;
884 /* Any section that was original placed AFTER the bss 379 } else {
885 section must now be adjusted by NEW_OFFSETS_SHIFT. */ 380 /* Any section that was originally placed AFTER the bss
886 381 * section should now be off by NEW_DATA2_SIZE. */
887 if (NEW_SECTION_H (nn).sh_offset >= new_base_offset) 382 if ( round_up (nsec->sh_offset, growme->sh_addralign) >=
888 NEW_SECTION_H (nn).sh_offset += new_offsets_shift; 383 new_data2_offset)
889 384 nsec->sh_offset += new_data2_size;
385 }
386
387 /* Any section that was originally placed after the section *
388 * header table should now be off by the size of one section
389 * header table entry. */
390 if (nsec->sh_offset > new_file_h->e_shoff)
391 nsec->sh_offset += new_file_h->e_shentsize;
392
393
890 /* If any section hdr refers to the section after the new .data 394 /* If any section hdr refers to the section after the new .data
891 section, make it refer to next one because we have inserted 395 * section, make it refer to next one because we have inserted a
892 a new section in between. */ 396 * new section in between. */
893 397 PATCH_INDEX (nsec->sh_link);
894 PATCH_INDEX (NEW_SECTION_H (nn).sh_link); 398
895 /* For symbol tables, info is a symbol table index, 399 /* For symbol tables, info is a symbol table index, so don't
896 so don't change it. */ 400 * change it. */
897 if (NEW_SECTION_H (nn).sh_type != SHT_SYMTAB 401 if (nsec->sh_type != SHT_SYMTAB && nsec->sh_type != SHT_DYNSYM)
898 && NEW_SECTION_H (nn).sh_type != SHT_DYNSYM) 402 PATCH_INDEX (nsec->sh_info);
899 PATCH_INDEX (NEW_SECTION_H (nn).sh_info); 403
900 404 /* Any section which used to be NOBITS will now becomes PROGBITS
901 /* Fix the type and alignment for the .sbss section */ 405 * if it's ALLOC-atable, unless, of cause, it's not the one we
902 if ((old_sbss_index != -1) && !strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".sbss")) 406 * decided to grow */
903 { 407 if ( (osec->sh_type == SHT_NOBITS) && (osec->sh_flags & SHF_ALLOC) &&
904 NEW_SECTION_H (nn).sh_type = SHT_PROGBITS; 408 (osec != growme ) ) {
905 NEW_SECTION_H (nn).sh_offset = round_up (NEW_SECTION_H (nn).sh_offset, 409 nsec->sh_type = SHT_PROGBITS;
906 NEW_SECTION_H (nn).sh_addralign); 410 }
907 } 411
908 412 /* Now, start to copy the content of sections */
909 /* Now, start to copy the content of sections. */ 413 if ( nsec->sh_type != SHT_NULL || nsec->sh_type != SHT_NOBITS ) {
910 if (NEW_SECTION_H (nn).sh_type == SHT_NULL 414
911 || NEW_SECTION_H (nn).sh_type == SHT_NOBITS) 415 /* Write out the sections. .data and .data1 (and data2,
912 continue; 416 * called ".data" in the strings table) get copied from the
913 417 * current process instead of the old file. */
914 /* Write out the sections. .data, .data1 and .sbss (and data2, called 418 caddr_t src = old_base + osec->sh_offset;
915 ".data" in the strings table) get copied from the current process 419 const char * secname = old_section_names + nsec->sh_name;
916 instead of the old file. */ 420 const char * names[] = {
917 if (!strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".data") 421 ".data",".sdata", ".lit4", ".lit8", ".sdata1", ".data1",
918 || !strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".data1") 422 ".sbss", NULL};
919 || !strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".got") 423 int i;
920 || !strcmp (old_section_names + NEW_SECTION_H (nn).sh_name, ".sbss")) 424
921 src = (caddr_t) OLD_SECTION_H (n).sh_addr; 425 for ( i=0; names[i] != NULL; i++ ) {
922 else 426 if ( ! strcmp (secname, names[i]) ) {
923 src = old_base + OLD_SECTION_H (n).sh_offset; 427 src = (caddr_t) osec->sh_addr;
924 428 break;
925 memcpy (NEW_SECTION_H (nn).sh_offset + new_base, src, 429 }
926 NEW_SECTION_H (nn).sh_size); 430 }
927 431
928 /* Adjust the HDRR offsets in .mdebug and copy the 432 memcpy (nsec->sh_offset + new_base, src, nsec->sh_size);
929 line data if it's in its usual 'hole' in the object. 433 }
930 Makes the new file debuggable with dbx. 434
931 patches up two problems: the absolute file offsets 435 old_mdebug_index = find_section (".mdebug", old_section_names,
932 in the HDRR record of .mdebug (see /usr/include/syms.h), and 436 old_name, old_file_h, old_section_h, 1);
933 the ld bug that gets the line table in a hole in the 437
934 elf file rather than in the .mdebug section proper. 438 #if defined (__sony_news) && defined (_SYSTYPE_SYSV)
935 David Anderson. davea@sgi.com Jan 16,1994. */ 439 if (nsec->sh_type == SHT_MIPS_DEBUG && old_mdebug_index != -1) {
936 if (n == old_mdebug_index) 440 int diff = nsec->sh_offset-OLD_SECTION_H(old_mdebug_index).sh_offset;
937 { 441 HDRR *phdr = (HDRR *)(nsec->sh_offset + new_base);
442
443 if (diff) {
444 phdr->cbLineOffset += diff;
445 phdr->cbDnOffset += diff;
446 phdr->cbPdOffset += diff;
447 phdr->cbSymOffset += diff;
448 phdr->cbOptOffset += diff;
449 phdr->cbAuxOffset += diff;
450 phdr->cbSsOffset += diff;
451 phdr->cbSsExtOffset += diff;
452 phdr->cbFdOffset += diff;
453 phdr->cbRfdOffset += diff;
454 phdr->cbExtOffset += diff;
455 }
456 }
457 #endif /* __sony_news && _SYSTYPE_SYSV */
458
459 #if __sgi
460 /* Adjust the HDRR offsets in .mdebug and copy the line data if
461 * it's in its usual 'hole' in the object. Makes the new file
462 * debuggable with dbx. patches up two problems: the absolute
463 * file offsets in the HDRR record of .mdebug (see
464 * /usr/include/syms.h), and the ld bug that gets the line table
465 * in a hole in the elf file rather than in the .mdebug section
466 * proper.
467 *
468 * David Anderson. davea@sgi.com Jan 16,1994 */
938 #define MDEBUGADJUST(__ct,__fileaddr) \ 469 #define MDEBUGADJUST(__ct,__fileaddr) \
939 if (n_phdrr->__ct > 0) \ 470 if (n_phdrr->__ct > 0) \
940 { \ 471 { \
941 n_phdrr->__fileaddr += movement; \ 472 n_phdrr->__fileaddr += movement; \
942 } 473 }
943 474
944 HDRR * o_phdrr = (HDRR *)((byte *)old_base + OLD_SECTION_H (n).sh_offset); 475 if (n == old_mdebug_index) {
945 HDRR * n_phdrr = (HDRR *)((byte *)new_base + NEW_SECTION_H (nn).sh_offset); 476 HDRR * o_phdrr = (HDRR *)((byte *)old_base + osec->sh_offset);
946 unsigned movement = new_offsets_shift; 477 HDRR * n_phdrr = (HDRR *)((byte *)new_base + nsec->sh_offset);
478 unsigned movement = new_data2_size;
947 479
948 MDEBUGADJUST (idnMax, cbDnOffset); 480 MDEBUGADJUST (idnMax, cbDnOffset);
949 MDEBUGADJUST (ipdMax, cbPdOffset); 481 MDEBUGADJUST (ipdMax, cbPdOffset);
950 MDEBUGADJUST (isymMax, cbSymOffset); 482 MDEBUGADJUST (isymMax, cbSymOffset);
951 MDEBUGADJUST (ioptMax, cbOptOffset); 483 MDEBUGADJUST (ioptMax, cbOptOffset);
953 MDEBUGADJUST (issMax, cbSsOffset); 485 MDEBUGADJUST (issMax, cbSsOffset);
954 MDEBUGADJUST (issExtMax, cbSsExtOffset); 486 MDEBUGADJUST (issExtMax, cbSsExtOffset);
955 MDEBUGADJUST (ifdMax, cbFdOffset); 487 MDEBUGADJUST (ifdMax, cbFdOffset);
956 MDEBUGADJUST (crfd, cbRfdOffset); 488 MDEBUGADJUST (crfd, cbRfdOffset);
957 MDEBUGADJUST (iextMax, cbExtOffset); 489 MDEBUGADJUST (iextMax, cbExtOffset);
958 /* The Line Section, being possible off in a hole of the object, 490
959 requires special handling. */ 491 /* The Line Section, being possible off in a hole of the
960 if (n_phdrr->cbLine > 0) 492 * object, requires special handling. */
961 { 493 if (n_phdrr->cbLine > 0) {
962 if (o_phdrr->cbLineOffset > (OLD_SECTION_H (n).sh_offset 494 if (o_phdrr->cbLineOffset >
963 + OLD_SECTION_H (n).sh_size)) 495 osec->sh_offset+ osec->sh_size){
964 { 496 /* line data is in a hole in elf. do special copy
965 /* line data is in a hole in elf. do special copy and adjust 497 * and adjust for this ld mistake. */
966 for this ld mistake.
967 */
968 n_phdrr->cbLineOffset += movement; 498 n_phdrr->cbLineOffset += movement;
969 499
970 memcpy (n_phdrr->cbLineOffset + new_base, 500 memcpy (n_phdrr->cbLineOffset + new_base,
971 o_phdrr->cbLineOffset + old_base, n_phdrr->cbLine); 501 o_phdrr->cbLineOffset + old_base, n_phdrr->cbLine);
972 } 502 } else {
973 else 503 /* somehow line data is in .mdebug as it is supposed
974 { 504 * to be. */
975 /* somehow line data is in .mdebug as it is supposed to be. */
976 MDEBUGADJUST (cbLine, cbLineOffset); 505 MDEBUGADJUST (cbLine, cbLineOffset);
977 } 506 }
978 } 507 }
979 } 508 }
980 509 #endif /* __sgi */
981 /* If it is the symbol table, its st_shndx field needs to be patched. */ 510 /* If it is the symbol table, its st_shndx field needs to be
982 if (NEW_SECTION_H (nn).sh_type == SHT_SYMTAB 511 * patched. */
983 || NEW_SECTION_H (nn).sh_type == SHT_DYNSYM) 512 if (nsec->sh_type == SHT_SYMTAB || nsec->sh_type == SHT_DYNSYM) {
984 { 513 unsigned int num = nsec->sh_size / nsec->sh_entsize;
985 l_Elf_Shdr *spt = &NEW_SECTION_H (nn); 514 ElfW(Sym) * sym = (ElfW(Sym) *)(nsec->sh_offset + new_base);
986 unsigned int num = spt->sh_size / spt->sh_entsize; 515 byte *symnames = ((byte *) new_base +
987 l_Elf_Sym * sym = (l_Elf_Sym *) (NEW_SECTION_H (nn).sh_offset 516 NEW_SECTION_H (nsec->sh_link).sh_offset);
988 + new_base); 517
989 for (; num--; sym++) 518 for (; num--; sym++) {
990 { 519 const char * symnam = (char *) (symnames + sym->st_name);
991 if (sym->st_shndx == SHN_UNDEF 520
992 || sym->st_shndx == SHN_ABS 521 /* Update the symbol values of _edata and _end. */
993 || sym->st_shndx == SHN_COMMON) 522 if (strcmp (symnam, "_end") == 0
994 continue; 523 || strcmp (symnam, "end") == 0
995 524 || strcmp (symnam, "_edata") == 0
525 || strcmp (symnam, "edata") == 0)
526 memcpy (&sym->st_value, &new_bss_addr,sizeof (new_bss_addr));
527
528
529 if ((sym->st_shndx == SHN_UNDEF) || (sym->st_shndx == SHN_ABS)
530 || (sym->st_shndx == SHN_COMMON)
531 || (sym->st_shndx >= SHN_LOPROC &&
532 sym->st_shndx <= SHN_HIPROC))
533 continue;
534
996 PATCH_INDEX (sym->st_shndx); 535 PATCH_INDEX (sym->st_shndx);
997 } 536 }
998 } 537 }
999 } 538 }
539
540 /* This loop seeks out relocation sections for the data section, so
541 * that it can undo relocations performed by the runtime linker. */
542 for (n = new_file_h->e_shnum - 1; n; n--) {
543 ElfW(Shdr) section = NEW_SECTION_H (n);
544
545 if ( section.sh_type == SHT_REL || section.sh_type == SHT_RELA ) {
546 /* This code handles two different size structs, but there
547 * should be no harm in that provided that r_offset is
548 * always the first member. */
549 ElfW(Shdr) * info = & NEW_SECTION_H(section.sh_info);
550 const char * nm = old_section_names + info->sh_name;
551
552 if (!strcmp (nm, ".data") || !strcmp (nm, ".sdata")
553 || !strcmp (nm, ".lit4") || !strcmp (nm, ".lit8")
554 || !strcmp (nm, ".sdata1") || !strcmp (nm, ".data1")) {
555 ElfW(Addr) offset = info->sh_addr - info->sh_offset;
556 caddr_t end, reloc = old_base + section.sh_offset;
557
558 for (end = reloc + section.sh_size; reloc < end;
559 reloc += section.sh_entsize) {
560 ElfW(Addr) addr = ((ElfW(Rel) *) reloc)->r_offset - offset;
561 #ifdef __alpha__
562 /* The Alpha ELF binutils currently have a bug that
563 * sometimes results in relocs that contain all
564 * zeroes. Work around this for now... */
565 if (((ElfW(Rel) *) reloc)->r_offset == 0)
566 continue;
567 #endif
568 memcpy (new_base + addr, old_base + addr,
569 sizeof(ElfW(Addr)));
570 }
571 }
572 }
573 }
574
575 #ifdef UNEXEC_USE_MAP_PRIVATE
576 if (lseek (new_file, 0, SEEK_SET) == -1)
577 fatal ("Can't rewind (%s): errno %d\n", new_name, errno);
578
579 if (write (new_file, new_base, new_file_size) != new_file_size)
580 fatal ("Can't write (%s): errno %d\n", new_name, errno);
581 #endif
1000 582
1001 /* Close the files and make the new file executable. */ 583 /* Close the files and make the new file executable. */
1002
1003 if (close (old_file)) 584 if (close (old_file))
1004 fatal ("Can't close (%s): errno %d\n", old_name, errno); 585 fatal ("Can't close (%s): errno %d\n", old_name, errno);
1005 586
1006 if (close (new_file)) 587 if (close (new_file))
1007 fatal ("Can't close (%s): errno %d\n", new_name, errno); 588 fatal ("Can't close (%s): errno %d\n", new_name, errno);
1008 589
1009 if (stat (new_name, &stat_buf) == -1) 590 if (stat (new_name, &stat_buf) == -1)
1010 fatal ("Can't stat (%s): errno %d\n", new_name, errno); 591 fatal ("Can't stat (%s): errno %d\n", new_name, errno);
1011 592
1012 n = umask (777); 593 n = umask (777);
1013 umask (n); 594 umask (n);
1014 stat_buf.st_mode |= 0111 & ~n; 595 stat_buf.st_mode |= 0111 & ~n;
1015 if (chmod (new_name, stat_buf.st_mode) == -1) 596 if (chmod (new_name, stat_buf.st_mode) == -1)
1016 fatal ("Can't chmod (%s): errno %d\n", new_name, errno); 597 fatal ("Can't chmod (%s): errno %d\n", new_name, errno);
1017
1018 return 0;
1019 } 598 }