Commit | Line | Data |
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4ef37be4 JB |
1 | /* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992 |
2 | Free Software Foundation, Inc. | |
3 | ||
4 | This program is free software; you can redistribute it and/or modify | |
5 | it under the terms of the GNU General Public License as published by | |
6 | the Free Software Foundation; either version 2, or (at your option) | |
7 | any later version. | |
8 | ||
9 | This program is distributed in the hope that it will be useful, | |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | GNU General Public License for more details. | |
13 | ||
14 | You should have received a copy of the GNU General Public License | |
15 | along with this program; if not, write to the Free Software | |
16 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
17 | ||
18 | In other words, you are welcome to use, share and improve this program. | |
19 | You are forbidden to forbid anyone else to use, share and improve | |
20 | what you give them. Help stamp out software-hoarding! */ | |
21 | ||
22 | ||
23 | /* | |
24 | * unexec.c - Convert a running program into an a.out file. | |
25 | * | |
26 | * Author: Spencer W. Thomas | |
27 | * Computer Science Dept. | |
28 | * University of Utah | |
29 | * Date: Tue Mar 2 1982 | |
30 | * Modified heavily since then. | |
31 | * | |
32 | * Synopsis: | |
33 | * unexec (new_name, a_name, data_start, bss_start, entry_address) | |
34 | * char *new_name, *a_name; | |
35 | * unsigned data_start, bss_start, entry_address; | |
36 | * | |
37 | * Takes a snapshot of the program and makes an a.out format file in the | |
38 | * file named by the string argument new_name. | |
39 | * If a_name is non-NULL, the symbol table will be taken from the given file. | |
40 | * On some machines, an existing a_name file is required. | |
41 | * | |
42 | * The boundaries within the a.out file may be adjusted with the data_start | |
43 | * and bss_start arguments. Either or both may be given as 0 for defaults. | |
44 | * | |
45 | * Data_start gives the boundary between the text segment and the data | |
46 | * segment of the program. The text segment can contain shared, read-only | |
47 | * program code and literal data, while the data segment is always unshared | |
48 | * and unprotected. Data_start gives the lowest unprotected address. | |
49 | * The value you specify may be rounded down to a suitable boundary | |
50 | * as required by the machine you are using. | |
51 | * | |
52 | * Specifying zero for data_start means the boundary between text and data | |
53 | * should not be the same as when the program was loaded. | |
54 | * If NO_REMAP is defined, the argument data_start is ignored and the | |
55 | * segment boundaries are never changed. | |
56 | * | |
57 | * Bss_start indicates how much of the data segment is to be saved in the | |
58 | * a.out file and restored when the program is executed. It gives the lowest | |
59 | * unsaved address, and is rounded up to a page boundary. The default when 0 | |
60 | * is given assumes that the entire data segment is to be stored, including | |
61 | * the previous data and bss as well as any additional storage allocated with | |
62 | * break (2). | |
63 | * | |
64 | * The new file is set up to start at entry_address. | |
65 | * | |
66 | * If you make improvements I'd like to get them too. | |
67 | * harpo!utah-cs!thomas, thomas@Utah-20 | |
68 | * | |
69 | */ | |
70 | ||
71 | /* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co. | |
72 | * ELF support added. | |
73 | * | |
74 | * Basic theory: the data space of the running process needs to be | |
75 | * dumped to the output file. Normally we would just enlarge the size | |
76 | * of .data, scooting everything down. But we can't do that in ELF, | |
77 | * because there is often something between the .data space and the | |
78 | * .bss space. | |
79 | * | |
80 | * In the temacs dump below, notice that the Global Offset Table | |
81 | * (.got) and the Dynamic link data (.dynamic) come between .data1 and | |
82 | * .bss. It does not work to overlap .data with these fields. | |
83 | * | |
84 | * The solution is to create a new .data segment. This segment is | |
85 | * filled with data from the current process. Since the contents of | |
86 | * various sections refer to sections by index, the new .data segment | |
87 | * is made the last in the table to avoid changing any existing index. | |
88 | ||
89 | * This is an example of how the section headers are changed. "Addr" | |
90 | * is a process virtual address. "Offset" is a file offset. | |
91 | ||
92 | raid:/nfs/raid/src/dist-18.56/src> dump -h temacs | |
93 | ||
94 | temacs: | |
95 | ||
96 | **** SECTION HEADER TABLE **** | |
97 | [No] Type Flags Addr Offset Size Name | |
98 | Link Info Adralgn Entsize | |
99 | ||
100 | [1] 1 2 0x80480d4 0xd4 0x13 .interp | |
101 | 0 0 0x1 0 | |
102 | ||
103 | [2] 5 2 0x80480e8 0xe8 0x388 .hash | |
104 | 3 0 0x4 0x4 | |
105 | ||
106 | [3] 11 2 0x8048470 0x470 0x7f0 .dynsym | |
107 | 4 1 0x4 0x10 | |
108 | ||
109 | [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr | |
110 | 0 0 0x1 0 | |
111 | ||
112 | [5] 9 2 0x8049010 0x1010 0x338 .rel.plt | |
113 | 3 7 0x4 0x8 | |
114 | ||
115 | [6] 1 6 0x8049348 0x1348 0x3 .init | |
116 | 0 0 0x4 0 | |
117 | ||
118 | [7] 1 6 0x804934c 0x134c 0x680 .plt | |
119 | 0 0 0x4 0x4 | |
120 | ||
121 | [8] 1 6 0x80499cc 0x19cc 0x3c56f .text | |
122 | 0 0 0x4 0 | |
123 | ||
124 | [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini | |
125 | 0 0 0x4 0 | |
126 | ||
127 | [10] 1 2 0x8085f40 0x3df40 0x69c .rodata | |
128 | 0 0 0x4 0 | |
129 | ||
130 | [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1 | |
131 | 0 0 0x4 0 | |
132 | ||
133 | [12] 1 3 0x8088330 0x3f330 0x20afc .data | |
134 | 0 0 0x4 0 | |
135 | ||
136 | [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1 | |
137 | 0 0 0x4 0 | |
138 | ||
139 | [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got | |
140 | 0 0 0x4 0x4 | |
141 | ||
142 | [15] 6 3 0x80a9874 0x60874 0x80 .dynamic | |
143 | 4 0 0x4 0x8 | |
144 | ||
145 | [16] 8 3 0x80a98f4 0x608f4 0x449c .bss | |
146 | 0 0 0x4 0 | |
147 | ||
148 | [17] 2 0 0 0x608f4 0x9b90 .symtab | |
149 | 18 371 0x4 0x10 | |
150 | ||
151 | [18] 3 0 0 0x6a484 0x8526 .strtab | |
152 | 0 0 0x1 0 | |
153 | ||
154 | [19] 3 0 0 0x729aa 0x93 .shstrtab | |
155 | 0 0 0x1 0 | |
156 | ||
157 | [20] 1 0 0 0x72a3d 0x68b7 .comment | |
158 | 0 0 0x1 0 | |
159 | ||
160 | raid:/nfs/raid/src/dist-18.56/src> dump -h xemacs | |
161 | ||
162 | xemacs: | |
163 | ||
164 | **** SECTION HEADER TABLE **** | |
165 | [No] Type Flags Addr Offset Size Name | |
166 | Link Info Adralgn Entsize | |
167 | ||
168 | [1] 1 2 0x80480d4 0xd4 0x13 .interp | |
169 | 0 0 0x1 0 | |
170 | ||
171 | [2] 5 2 0x80480e8 0xe8 0x388 .hash | |
172 | 3 0 0x4 0x4 | |
173 | ||
174 | [3] 11 2 0x8048470 0x470 0x7f0 .dynsym | |
175 | 4 1 0x4 0x10 | |
176 | ||
177 | [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr | |
178 | 0 0 0x1 0 | |
179 | ||
180 | [5] 9 2 0x8049010 0x1010 0x338 .rel.plt | |
181 | 3 7 0x4 0x8 | |
182 | ||
183 | [6] 1 6 0x8049348 0x1348 0x3 .init | |
184 | 0 0 0x4 0 | |
185 | ||
186 | [7] 1 6 0x804934c 0x134c 0x680 .plt | |
187 | 0 0 0x4 0x4 | |
188 | ||
189 | [8] 1 6 0x80499cc 0x19cc 0x3c56f .text | |
190 | 0 0 0x4 0 | |
191 | ||
192 | [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini | |
193 | 0 0 0x4 0 | |
194 | ||
195 | [10] 1 2 0x8085f40 0x3df40 0x69c .rodata | |
196 | 0 0 0x4 0 | |
197 | ||
198 | [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1 | |
199 | 0 0 0x4 0 | |
200 | ||
201 | [12] 1 3 0x8088330 0x3f330 0x20afc .data | |
202 | 0 0 0x4 0 | |
203 | ||
204 | [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1 | |
205 | 0 0 0x4 0 | |
206 | ||
207 | [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got | |
208 | 0 0 0x4 0x4 | |
209 | ||
210 | [15] 6 3 0x80a9874 0x60874 0x80 .dynamic | |
211 | 4 0 0x4 0x8 | |
212 | ||
213 | [16] 8 3 0x80c6800 0x7d800 0 .bss | |
214 | 0 0 0x4 0 | |
215 | ||
216 | [17] 2 0 0 0x7d800 0x9b90 .symtab | |
217 | 18 371 0x4 0x10 | |
218 | ||
219 | [18] 3 0 0 0x87390 0x8526 .strtab | |
220 | 0 0 0x1 0 | |
221 | ||
222 | [19] 3 0 0 0x8f8b6 0x93 .shstrtab | |
223 | 0 0 0x1 0 | |
224 | ||
225 | [20] 1 0 0 0x8f949 0x68b7 .comment | |
226 | 0 0 0x1 0 | |
227 | ||
228 | [21] 1 3 0x80a98f4 0x608f4 0x1cf0c .data | |
229 | 0 0 0x4 0 | |
230 | ||
231 | * This is an example of how the file header is changed. "Shoff" is | |
232 | * the section header offset within the file. Since that table is | |
233 | * after the new .data section, it is moved. "Shnum" is the number of | |
234 | * sections, which we increment. | |
235 | * | |
236 | * "Phoff" is the file offset to the program header. "Phentsize" and | |
237 | * "Shentsz" are the program and section header entries sizes respectively. | |
238 | * These can be larger than the apparent struct sizes. | |
239 | ||
240 | raid:/nfs/raid/src/dist-18.56/src> dump -f temacs | |
241 | ||
242 | temacs: | |
243 | ||
244 | **** ELF HEADER **** | |
245 | Class Data Type Machine Version | |
246 | Entry Phoff Shoff Flags Ehsize | |
247 | Phentsize Phnum Shentsz Shnum Shstrndx | |
248 | ||
249 | 1 1 2 3 1 | |
250 | 0x80499cc 0x34 0x792f4 0 0x34 | |
251 | 0x20 5 0x28 21 19 | |
252 | ||
253 | raid:/nfs/raid/src/dist-18.56/src> dump -f xemacs | |
254 | ||
255 | xemacs: | |
256 | ||
257 | **** ELF HEADER **** | |
258 | Class Data Type Machine Version | |
259 | Entry Phoff Shoff Flags Ehsize | |
260 | Phentsize Phnum Shentsz Shnum Shstrndx | |
261 | ||
262 | 1 1 2 3 1 | |
263 | 0x80499cc 0x34 0x96200 0 0x34 | |
264 | 0x20 5 0x28 22 19 | |
265 | ||
266 | * These are the program headers. "Offset" is the file offset to the | |
267 | * segment. "Vaddr" is the memory load address. "Filesz" is the | |
268 | * segment size as it appears in the file, and "Memsz" is the size in | |
269 | * memory. Below, the third segment is the code and the fourth is the | |
270 | * data: the difference between Filesz and Memsz is .bss | |
271 | ||
272 | raid:/nfs/raid/src/dist-18.56/src> dump -o temacs | |
273 | ||
274 | temacs: | |
275 | ***** PROGRAM EXECUTION HEADER ***** | |
276 | Type Offset Vaddr Paddr | |
277 | Filesz Memsz Flags Align | |
278 | ||
279 | 6 0x34 0x8048034 0 | |
280 | 0xa0 0xa0 5 0 | |
281 | ||
282 | 3 0xd4 0 0 | |
283 | 0x13 0 4 0 | |
284 | ||
285 | 1 0x34 0x8048034 0 | |
286 | 0x3f2f9 0x3f2f9 5 0x1000 | |
287 | ||
288 | 1 0x3f330 0x8088330 0 | |
289 | 0x215c4 0x25a60 7 0x1000 | |
290 | ||
291 | 2 0x60874 0x80a9874 0 | |
292 | 0x80 0 7 0 | |
293 | ||
294 | raid:/nfs/raid/src/dist-18.56/src> dump -o xemacs | |
295 | ||
296 | xemacs: | |
297 | ***** PROGRAM EXECUTION HEADER ***** | |
298 | Type Offset Vaddr Paddr | |
299 | Filesz Memsz Flags Align | |
300 | ||
301 | 6 0x34 0x8048034 0 | |
302 | 0xa0 0xa0 5 0 | |
303 | ||
304 | 3 0xd4 0 0 | |
305 | 0x13 0 4 0 | |
306 | ||
307 | 1 0x34 0x8048034 0 | |
308 | 0x3f2f9 0x3f2f9 5 0x1000 | |
309 | ||
310 | 1 0x3f330 0x8088330 0 | |
311 | 0x3e4d0 0x3e4d0 7 0x1000 | |
312 | ||
313 | 2 0x60874 0x80a9874 0 | |
314 | 0x80 0 7 0 | |
315 | ||
316 | ||
317 | */ | |
318 | \f | |
319 | /* Modified by wtien@urbana.mcd.mot.com of Motorola Inc. | |
320 | * | |
321 | * The above mechanism does not work if the unexeced ELF file is being | |
322 | * re-layout by other applications (such as `strip'). All the applications | |
323 | * that re-layout the internal of ELF will layout all sections in ascending | |
324 | * order of their file offsets. After the re-layout, the data2 section will | |
325 | * still be the LAST section in the section header vector, but its file offset | |
326 | * is now being pushed far away down, and causes part of it not to be mapped | |
327 | * in (ie. not covered by the load segment entry in PHDR vector), therefore | |
328 | * causes the new binary to fail. | |
329 | * | |
330 | * The solution is to modify the unexec algorithm to insert the new data2 | |
331 | * section header right before the new bss section header, so their file | |
332 | * offsets will be in the ascending order. Since some of the section's (all | |
333 | * sections AFTER the bss section) indexes are now changed, we also need to | |
334 | * modify some fields to make them point to the right sections. This is done | |
335 | * by macro PATCH_INDEX. All the fields that need to be patched are: | |
336 | * | |
337 | * 1. ELF header e_shstrndx field. | |
338 | * 2. section header sh_link and sh_info field. | |
339 | * 3. symbol table entry st_shndx field. | |
340 | * | |
341 | * The above example now should look like: | |
342 | ||
343 | **** SECTION HEADER TABLE **** | |
344 | [No] Type Flags Addr Offset Size Name | |
345 | Link Info Adralgn Entsize | |
346 | ||
347 | [1] 1 2 0x80480d4 0xd4 0x13 .interp | |
348 | 0 0 0x1 0 | |
349 | ||
350 | [2] 5 2 0x80480e8 0xe8 0x388 .hash | |
351 | 3 0 0x4 0x4 | |
352 | ||
353 | [3] 11 2 0x8048470 0x470 0x7f0 .dynsym | |
354 | 4 1 0x4 0x10 | |
355 | ||
356 | [4] 3 2 0x8048c60 0xc60 0x3ad .dynstr | |
357 | 0 0 0x1 0 | |
358 | ||
359 | [5] 9 2 0x8049010 0x1010 0x338 .rel.plt | |
360 | 3 7 0x4 0x8 | |
361 | ||
362 | [6] 1 6 0x8049348 0x1348 0x3 .init | |
363 | 0 0 0x4 0 | |
364 | ||
365 | [7] 1 6 0x804934c 0x134c 0x680 .plt | |
366 | 0 0 0x4 0x4 | |
367 | ||
368 | [8] 1 6 0x80499cc 0x19cc 0x3c56f .text | |
369 | 0 0 0x4 0 | |
370 | ||
371 | [9] 1 6 0x8085f3c 0x3df3c 0x3 .fini | |
372 | 0 0 0x4 0 | |
373 | ||
374 | [10] 1 2 0x8085f40 0x3df40 0x69c .rodata | |
375 | 0 0 0x4 0 | |
376 | ||
377 | [11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1 | |
378 | 0 0 0x4 0 | |
379 | ||
380 | [12] 1 3 0x8088330 0x3f330 0x20afc .data | |
381 | 0 0 0x4 0 | |
382 | ||
383 | [13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1 | |
384 | 0 0 0x4 0 | |
385 | ||
386 | [14] 1 3 0x80a96cc 0x606cc 0x1a8 .got | |
387 | 0 0 0x4 0x4 | |
388 | ||
389 | [15] 6 3 0x80a9874 0x60874 0x80 .dynamic | |
390 | 4 0 0x4 0x8 | |
391 | ||
392 | [16] 1 3 0x80a98f4 0x608f4 0x1cf0c .data | |
393 | 0 0 0x4 0 | |
394 | ||
395 | [17] 8 3 0x80c6800 0x7d800 0 .bss | |
396 | 0 0 0x4 0 | |
397 | ||
398 | [18] 2 0 0 0x7d800 0x9b90 .symtab | |
399 | 19 371 0x4 0x10 | |
400 | ||
401 | [19] 3 0 0 0x87390 0x8526 .strtab | |
402 | 0 0 0x1 0 | |
403 | ||
404 | [20] 3 0 0 0x8f8b6 0x93 .shstrtab | |
405 | 0 0 0x1 0 | |
406 | ||
407 | [21] 1 0 0 0x8f949 0x68b7 .comment | |
408 | 0 0 0x1 0 | |
409 | ||
410 | */ | |
411 | \f | |
412 | #include <sys/types.h> | |
413 | #include <stdio.h> | |
414 | #include <sys/stat.h> | |
415 | #include <memory.h> | |
416 | #include <string.h> | |
417 | #include <errno.h> | |
418 | #include <unistd.h> | |
419 | #include <fcntl.h> | |
420 | #include <elf.h> | |
5416d1ee | 421 | #include <syms.h> /* for HDRR declaration */ |
4ef37be4 JB |
422 | #include <sys/mman.h> |
423 | ||
424 | #ifndef emacs | |
425 | #define fatal(a, b, c) fprintf(stderr, a, b, c), exit(1) | |
426 | #else | |
427 | extern void fatal(char *, ...); | |
428 | #endif | |
429 | ||
430 | /* Get the address of a particular section or program header entry, | |
431 | * accounting for the size of the entries. | |
432 | */ | |
433 | ||
434 | #define OLD_SECTION_H(n) \ | |
435 | (*(Elf32_Shdr *) ((byte *) old_section_h + old_file_h->e_shentsize * (n))) | |
436 | #define NEW_SECTION_H(n) \ | |
437 | (*(Elf32_Shdr *) ((byte *) new_section_h + new_file_h->e_shentsize * (n))) | |
438 | #define OLD_PROGRAM_H(n) \ | |
439 | (*(Elf32_Phdr *) ((byte *) old_program_h + old_file_h->e_phentsize * (n))) | |
440 | #define NEW_PROGRAM_H(n) \ | |
441 | (*(Elf32_Phdr *) ((byte *) new_program_h + new_file_h->e_phentsize * (n))) | |
442 | ||
443 | #define PATCH_INDEX(n) \ | |
444 | do { \ | |
445 | if ((n) >= old_bss_index) \ | |
446 | (n)++; } while (0) | |
447 | typedef unsigned char byte; | |
448 | ||
449 | /* Round X up to a multiple of Y. */ | |
450 | ||
451 | int | |
452 | round_up (x, y) | |
453 | int x, y; | |
454 | { | |
455 | int rem = x % y; | |
456 | if (rem == 0) | |
457 | return x; | |
458 | return x - rem + y; | |
459 | } | |
460 | ||
461 | /* **************************************************************** | |
462 | * unexec | |
463 | * | |
464 | * driving logic. | |
465 | * | |
466 | * In ELF, this works by replacing the old .bss section with a new | |
467 | * .data section, and inserting an empty .bss immediately afterwards. | |
468 | * | |
469 | */ | |
470 | void | |
471 | unexec (new_name, old_name, data_start, bss_start, entry_address) | |
472 | char *new_name, *old_name; | |
473 | unsigned data_start, bss_start, entry_address; | |
474 | { | |
475 | extern unsigned int bss_end; | |
476 | int new_file, old_file, new_file_size; | |
477 | ||
5416d1ee | 478 | /* Pointers to the base of the image of the two files. */ |
4ef37be4 JB |
479 | caddr_t old_base, new_base; |
480 | ||
481 | /* Pointers to the file, program and section headers for the old and new | |
5416d1ee | 482 | files. */ |
4ef37be4 JB |
483 | Elf32_Ehdr *old_file_h, *new_file_h; |
484 | Elf32_Phdr *old_program_h, *new_program_h; | |
485 | Elf32_Shdr *old_section_h, *new_section_h; | |
486 | ||
5416d1ee | 487 | /* Point to the section name table in the old file. */ |
4ef37be4 JB |
488 | char *old_section_names; |
489 | ||
490 | Elf32_Addr old_bss_addr, new_bss_addr; | |
491 | Elf32_Word old_bss_size, new_data2_size; | |
492 | Elf32_Off new_data2_offset; | |
493 | Elf32_Addr new_data2_addr; | |
494 | ||
495 | int n, nn, old_bss_index, old_data_index, new_data2_index; | |
5416d1ee | 496 | int old_mdebug_index; |
4ef37be4 JB |
497 | struct stat stat_buf; |
498 | ||
5416d1ee | 499 | /* Open the old file & map it into the address space. */ |
4ef37be4 JB |
500 | |
501 | old_file = open (old_name, O_RDONLY); | |
502 | ||
503 | if (old_file < 0) | |
504 | fatal ("Can't open %s for reading: errno %d\n", old_name, errno); | |
505 | ||
506 | if (fstat (old_file, &stat_buf) == -1) | |
507 | fatal ("Can't fstat(%s): errno %d\n", old_name, errno); | |
508 | ||
509 | old_base = mmap (0, stat_buf.st_size, PROT_READ, MAP_SHARED, old_file, 0); | |
510 | ||
511 | if (old_base == (caddr_t) -1) | |
512 | fatal ("Can't mmap(%s): errno %d\n", old_name, errno); | |
513 | ||
514 | #ifdef DEBUG | |
515 | fprintf (stderr, "mmap(%s, %x) -> %x\n", old_name, stat_buf.st_size, | |
516 | old_base); | |
517 | #endif | |
518 | ||
5416d1ee | 519 | /* Get pointers to headers & section names. */ |
4ef37be4 JB |
520 | |
521 | old_file_h = (Elf32_Ehdr *) old_base; | |
522 | old_program_h = (Elf32_Phdr *) ((byte *) old_base + old_file_h->e_phoff); | |
523 | old_section_h = (Elf32_Shdr *) ((byte *) old_base + old_file_h->e_shoff); | |
5416d1ee RS |
524 | old_section_names |
525 | = (char *) old_base + OLD_SECTION_H (old_file_h->e_shstrndx).sh_offset; | |
526 | ||
527 | /* Find the mdebug section, if any. */ | |
528 | for (old_mdebug_index = 1; old_mdebug_index < old_file_h->e_shnum; old_mdebug_index++) | |
529 | { | |
530 | #ifdef DEBUG | |
531 | fprintf (stderr, "Looking for .mdebug - found %s\n", | |
532 | old_section_names + OLD_SECTION_H(old_mdebug_index).sh_name); | |
533 | #endif | |
534 | if (!strcmp (old_section_names + OLD_SECTION_H(old_mdebug_index).sh_name, | |
535 | ".mdebug")) | |
536 | break; | |
537 | } | |
538 | if (old_mdebug_index == old_file_h->e_shnum) | |
539 | old_mdebug_index = -1; /* just means no such section was present */ | |
4ef37be4 JB |
540 | |
541 | /* Find the old .bss section. Figure out parameters of the new | |
5416d1ee | 542 | data2 and bss sections. */ |
4ef37be4 JB |
543 | |
544 | for (old_bss_index = 1; old_bss_index < old_file_h->e_shnum; old_bss_index++) | |
545 | { | |
546 | #ifdef DEBUG | |
547 | fprintf (stderr, "Looking for .bss - found %s\n", | |
548 | old_section_names + OLD_SECTION_H(old_bss_index).sh_name); | |
549 | #endif | |
550 | if (!strcmp (old_section_names + OLD_SECTION_H(old_bss_index).sh_name, | |
551 | ".bss")) | |
552 | break; | |
553 | } | |
554 | if (old_bss_index == old_file_h->e_shnum) | |
555 | fatal ("Can't find .bss in %s.\n", old_name, 0); | |
556 | ||
5416d1ee RS |
557 | old_bss_addr = OLD_SECTION_H (old_bss_index).sh_addr; |
558 | old_bss_size = OLD_SECTION_H (old_bss_index).sh_size; | |
4ef37be4 JB |
559 | #if defined(emacs) || !defined(DEBUG) |
560 | bss_end = (unsigned int) sbrk (0); | |
561 | new_bss_addr = (Elf32_Addr) bss_end; | |
562 | #else | |
563 | new_bss_addr = old_bss_addr + old_bss_size + 0x1234; | |
564 | #endif | |
565 | new_data2_addr = old_bss_addr; | |
566 | new_data2_size = new_bss_addr - old_bss_addr; | |
5416d1ee | 567 | new_data2_offset = OLD_SECTION_H (old_bss_index).sh_offset; |
4ef37be4 JB |
568 | |
569 | #ifdef DEBUG | |
570 | fprintf (stderr, "old_bss_index %d\n", old_bss_index); | |
571 | fprintf (stderr, "old_bss_addr %x\n", old_bss_addr); | |
572 | fprintf (stderr, "old_bss_size %x\n", old_bss_size); | |
573 | fprintf (stderr, "new_bss_addr %x\n", new_bss_addr); | |
574 | fprintf (stderr, "new_data2_addr %x\n", new_data2_addr); | |
575 | fprintf (stderr, "new_data2_size %x\n", new_data2_size); | |
576 | fprintf (stderr, "new_data2_offset %x\n", new_data2_offset); | |
577 | #endif | |
578 | ||
579 | if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size) | |
580 | fatal (".bss shrank when undumping???\n", 0, 0); | |
581 | ||
5416d1ee RS |
582 | /* Set the output file to the right size and mmap it. Set |
583 | pointers to various interesting objects. stat_buf still has | |
584 | old_file data. */ | |
4ef37be4 JB |
585 | |
586 | new_file = open (new_name, O_RDWR | O_CREAT, 0666); | |
587 | if (new_file < 0) | |
5416d1ee | 588 | fatal ("Can't creat (%s): errno %d\n", new_name, errno); |
4ef37be4 JB |
589 | |
590 | new_file_size = stat_buf.st_size + old_file_h->e_shentsize + new_data2_size; | |
591 | ||
592 | if (ftruncate (new_file, new_file_size)) | |
5416d1ee | 593 | fatal ("Can't ftruncate (%s): errno %d\n", new_name, errno); |
4ef37be4 JB |
594 | |
595 | new_base = mmap (0, new_file_size, PROT_READ | PROT_WRITE, MAP_SHARED, | |
596 | new_file, 0); | |
597 | ||
598 | if (new_base == (caddr_t) -1) | |
5416d1ee | 599 | fatal ("Can't mmap (%s): errno %d\n", new_name, errno); |
4ef37be4 JB |
600 | |
601 | new_file_h = (Elf32_Ehdr *) new_base; | |
602 | new_program_h = (Elf32_Phdr *) ((byte *) new_base + old_file_h->e_phoff); | |
5416d1ee RS |
603 | new_section_h |
604 | = (Elf32_Shdr *) ((byte *) new_base + old_file_h->e_shoff | |
605 | + new_data2_size); | |
4ef37be4 JB |
606 | |
607 | /* Make our new file, program and section headers as copies of the | |
5416d1ee | 608 | originals. */ |
4ef37be4 JB |
609 | |
610 | memcpy (new_file_h, old_file_h, old_file_h->e_ehsize); | |
611 | memcpy (new_program_h, old_program_h, | |
612 | old_file_h->e_phnum * old_file_h->e_phentsize); | |
613 | ||
614 | /* Modify the e_shstrndx if necessary. */ | |
615 | PATCH_INDEX (new_file_h->e_shstrndx); | |
616 | ||
617 | /* Fix up file header. We'll add one section. Section header is | |
5416d1ee | 618 | further away now. */ |
4ef37be4 JB |
619 | |
620 | new_file_h->e_shoff += new_data2_size; | |
621 | new_file_h->e_shnum += 1; | |
622 | ||
623 | #ifdef DEBUG | |
624 | fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff); | |
625 | fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum); | |
626 | fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff); | |
627 | fprintf (stderr, "New section count %d\n", new_file_h->e_shnum); | |
628 | #endif | |
629 | ||
630 | /* Fix up a new program header. Extend the writable data segment so | |
5416d1ee RS |
631 | that the bss area is covered too. Find that segment by looking |
632 | for a segment that ends just before the .bss area. Make sure | |
633 | that no segments are above the new .data2. Put a loop at the end | |
634 | to adjust the offset and address of any segment that is above | |
635 | data2, just in case we decide to allow this later. */ | |
4ef37be4 JB |
636 | |
637 | for (n = new_file_h->e_phnum - 1; n >= 0; n--) | |
638 | { | |
639 | /* Compute maximum of all requirements for alignment of section. */ | |
640 | int alignment = (NEW_PROGRAM_H (n)).p_align; | |
641 | if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment) | |
642 | alignment = OLD_SECTION_H (old_bss_index).sh_addralign; | |
643 | ||
7260e339 JB |
644 | /* Supposedly this condition is okay for the SGI. */ |
645 | #if 0 | |
5416d1ee | 646 | if (NEW_PROGRAM_H (n).p_vaddr + NEW_PROGRAM_H (n).p_filesz > old_bss_addr) |
4ef37be4 | 647 | fatal ("Program segment above .bss in %s\n", old_name, 0); |
7260e339 | 648 | #endif |
4ef37be4 | 649 | |
5416d1ee | 650 | if (NEW_PROGRAM_H (n).p_type == PT_LOAD |
4ef37be4 JB |
651 | && (round_up ((NEW_PROGRAM_H (n)).p_vaddr |
652 | + (NEW_PROGRAM_H (n)).p_filesz, | |
653 | alignment) | |
654 | == round_up (old_bss_addr, alignment))) | |
655 | break; | |
656 | } | |
657 | if (n < 0) | |
658 | fatal ("Couldn't find segment next to .bss in %s\n", old_name, 0); | |
659 | ||
5416d1ee RS |
660 | NEW_PROGRAM_H (n).p_filesz += new_data2_size; |
661 | NEW_PROGRAM_H (n).p_memsz = NEW_PROGRAM_H (n).p_filesz; | |
4ef37be4 | 662 | |
5416d1ee | 663 | #if 1 /* Maybe allow section after data2 - does this ever happen? */ |
4ef37be4 JB |
664 | for (n = new_file_h->e_phnum - 1; n >= 0; n--) |
665 | { | |
5416d1ee RS |
666 | if (NEW_PROGRAM_H (n).p_vaddr |
667 | && NEW_PROGRAM_H (n).p_vaddr >= new_data2_addr) | |
668 | NEW_PROGRAM_H (n).p_vaddr += new_data2_size - old_bss_size; | |
4ef37be4 | 669 | |
5416d1ee RS |
670 | if (NEW_PROGRAM_H (n).p_offset >= new_data2_offset) |
671 | NEW_PROGRAM_H (n).p_offset += new_data2_size; | |
4ef37be4 JB |
672 | } |
673 | #endif | |
674 | ||
675 | /* Fix up section headers based on new .data2 section. Any section | |
5416d1ee RS |
676 | whose offset or virtual address is after the new .data2 section |
677 | gets its value adjusted. .bss size becomes zero and new address | |
678 | is set. data2 section header gets added by copying the existing | |
679 | .data header and modifying the offset, address and size. */ | |
4ef37be4 JB |
680 | for (old_data_index = 1; old_data_index < old_file_h->e_shnum; |
681 | old_data_index++) | |
5416d1ee | 682 | if (!strcmp (old_section_names + OLD_SECTION_H (old_data_index).sh_name, |
4ef37be4 JB |
683 | ".data")) |
684 | break; | |
685 | if (old_data_index == old_file_h->e_shnum) | |
686 | fatal ("Can't find .data in %s.\n", old_name, 0); | |
687 | ||
688 | /* Walk through all section headers, insert the new data2 section right | |
5416d1ee | 689 | before the new bss section. */ |
4ef37be4 JB |
690 | for (n = 1, nn = 1; n < old_file_h->e_shnum; n++, nn++) |
691 | { | |
692 | caddr_t src; | |
5416d1ee | 693 | /* If it is bss section, insert the new data2 section before it. */ |
4ef37be4 JB |
694 | if (n == old_bss_index) |
695 | { | |
5416d1ee RS |
696 | /* Steal the data section header for this data2 section. */ |
697 | memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (old_data_index), | |
4ef37be4 JB |
698 | new_file_h->e_shentsize); |
699 | ||
5416d1ee RS |
700 | NEW_SECTION_H (nn).sh_addr = new_data2_addr; |
701 | NEW_SECTION_H (nn).sh_offset = new_data2_offset; | |
702 | NEW_SECTION_H (nn).sh_size = new_data2_size; | |
4ef37be4 JB |
703 | /* Use the bss section's alignment. This will assure that the |
704 | new data2 section always be placed in the same spot as the old | |
5416d1ee RS |
705 | bss section by any other application. */ |
706 | NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (n).sh_addralign; | |
4ef37be4 | 707 | |
5416d1ee RS |
708 | /* Now copy over what we have in the memory now. */ |
709 | memcpy (NEW_SECTION_H (nn).sh_offset + new_base, | |
710 | (caddr_t) OLD_SECTION_H (n).sh_addr, | |
4ef37be4 JB |
711 | new_data2_size); |
712 | nn++; | |
713 | } | |
714 | ||
5416d1ee | 715 | memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n), |
4ef37be4 JB |
716 | old_file_h->e_shentsize); |
717 | ||
718 | /* The new bss section's size is zero, and its file offset and virtual | |
5416d1ee | 719 | address should be off by NEW_DATA2_SIZE. */ |
4ef37be4 JB |
720 | if (n == old_bss_index) |
721 | { | |
722 | /* NN should be `old_bss_index + 1' at this point. */ | |
5416d1ee RS |
723 | NEW_SECTION_H (nn).sh_offset += new_data2_size; |
724 | NEW_SECTION_H (nn).sh_addr += new_data2_size; | |
4ef37be4 JB |
725 | /* Let the new bss section address alignment be the same as the |
726 | section address alignment followed the old bss section, so | |
5416d1ee RS |
727 | this section will be placed in exactly the same place. */ |
728 | NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (nn).sh_addralign; | |
729 | NEW_SECTION_H (nn).sh_size = 0; | |
4ef37be4 JB |
730 | } |
731 | /* Any section that was original placed AFTER the bss section should now | |
5416d1ee RS |
732 | be off by NEW_DATA2_SIZE. */ |
733 | else if (NEW_SECTION_H (nn).sh_offset >= new_data2_offset) | |
734 | NEW_SECTION_H (nn).sh_offset += new_data2_size; | |
4ef37be4 JB |
735 | |
736 | /* If any section hdr refers to the section after the new .data | |
737 | section, make it refer to next one because we have inserted | |
5416d1ee | 738 | a new section in between. */ |
4ef37be4 | 739 | |
5416d1ee | 740 | PATCH_INDEX (NEW_SECTION_H (nn).sh_link); |
019f2b8f RS |
741 | /* For symbol tables, info is a symbol table index, |
742 | so don't change it. */ | |
743 | if (NEW_SECTION_H (nn).sh_type != SHT_SYMTAB | |
744 | && NEW_SECTION_H (nn).sh_type != SHT_DYNSYM) | |
745 | PATCH_INDEX (NEW_SECTION_H (nn).sh_info); | |
4ef37be4 JB |
746 | |
747 | /* Now, start to copy the content of sections. */ | |
5416d1ee RS |
748 | if (NEW_SECTION_H (nn).sh_type == SHT_NULL |
749 | || NEW_SECTION_H (nn).sh_type == SHT_NOBITS) | |
4ef37be4 JB |
750 | continue; |
751 | ||
752 | /* Write out the sections. .data and .data1 (and data2, called | |
5416d1ee RS |
753 | ".data" in the strings table) get copied from the current process |
754 | instead of the old file. */ | |
755 | if (!strcmp (old_section_names + NEW_SECTION_H (n).sh_name, ".data") | |
756 | || !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name), | |
4ef37be4 | 757 | ".data1")) |
5416d1ee | 758 | src = (caddr_t) OLD_SECTION_H (n).sh_addr; |
4ef37be4 | 759 | else |
5416d1ee | 760 | src = old_base + OLD_SECTION_H (n).sh_offset; |
4ef37be4 | 761 | |
5416d1ee RS |
762 | memcpy (NEW_SECTION_H (nn).sh_offset + new_base, src, |
763 | NEW_SECTION_H (nn).sh_size); | |
764 | ||
765 | /* Adjust the HDRR offsets in .mdebug and copy the | |
766 | line data if it's in its usual 'hole' in the object. | |
767 | Makes the new file debuggable with dbx. | |
768 | patches up two problems: the absolute file offsets | |
769 | in the HDRR record of .mdebug (see /usr/include/syms.h), and | |
770 | the ld bug that gets the line table in a hole in the | |
771 | elf file rather than in the .mdebug section proper. | |
772 | David Anderson. davea@sgi.com Jan 16,1994. */ | |
773 | if (n == old_mdebug_index) | |
774 | { | |
775 | #define MDEBUGADJUST(__ct,__fileaddr) \ | |
776 | if (n_phdrr->__ct > 0) \ | |
777 | { \ | |
778 | n_phdrr->__fileaddr += movement; \ | |
779 | } | |
780 | ||
781 | HDRR * o_phdrr = (HDRR *)((byte *)old_base + OLD_SECTION_H (n).sh_offset); | |
782 | HDRR * n_phdrr = (HDRR *)((byte *)new_base + NEW_SECTION_H (nn).sh_offset); | |
783 | unsigned movement = new_data2_size; | |
784 | ||
785 | MDEBUGADJUST (idnMax, cbDnOffset); | |
786 | MDEBUGADJUST (ipdMax, cbPdOffset); | |
787 | MDEBUGADJUST (isymMax, cbSymOffset); | |
788 | MDEBUGADJUST (ioptMax, cbOptOffset); | |
789 | MDEBUGADJUST (iauxMax, cbAuxOffset); | |
790 | MDEBUGADJUST (issMax, cbSsOffset); | |
791 | MDEBUGADJUST (issExtMax, cbSsExtOffset); | |
792 | MDEBUGADJUST (ifdMax, cbFdOffset); | |
793 | MDEBUGADJUST (crfd, cbRfdOffset); | |
794 | MDEBUGADJUST (iextMax, cbExtOffset); | |
795 | /* The Line Section, being possible off in a hole of the object, | |
796 | requires special handling. */ | |
797 | if (n_phdrr->cbLine > 0) | |
798 | { | |
799 | if (o_phdrr->cbLineOffset > (OLD_SECTION_H (n).sh_offset | |
800 | + OLD_SECTION_H (n).sh_size)) | |
801 | { | |
802 | /* line data is in a hole in elf. do special copy and adjust | |
803 | for this ld mistake. | |
804 | */ | |
805 | n_phdrr->cbLineOffset += movement; | |
806 | ||
807 | memcpy (n_phdrr->cbLineOffset + new_base, | |
808 | o_phdrr->cbLineOffset + old_base, n_phdrr->cbLine); | |
809 | } | |
810 | else | |
811 | { | |
812 | /* somehow line data is in .mdebug as it is supposed to be. */ | |
813 | MDEBUGADJUST (cbLine, cbLineOffset); | |
814 | } | |
815 | } | |
816 | } | |
4ef37be4 JB |
817 | |
818 | /* If it is the symbol table, its st_shndx field needs to be patched. */ | |
5416d1ee RS |
819 | if (NEW_SECTION_H (nn).sh_type == SHT_SYMTAB |
820 | || NEW_SECTION_H (nn).sh_type == SHT_DYNSYM) | |
4ef37be4 | 821 | { |
5416d1ee | 822 | Elf32_Shdr *spt = &NEW_SECTION_H (nn); |
4ef37be4 | 823 | unsigned int num = spt->sh_size / spt->sh_entsize; |
5416d1ee RS |
824 | Elf32_Sym * sym = (Elf32_Sym *) (NEW_SECTION_H (nn).sh_offset |
825 | + new_base); | |
4ef37be4 JB |
826 | for (; num--; sym++) |
827 | { | |
5416d1ee RS |
828 | if (sym->st_shndx == SHN_UNDEF |
829 | || sym->st_shndx == SHN_ABS | |
830 | || sym->st_shndx == SHN_COMMON) | |
4ef37be4 JB |
831 | continue; |
832 | ||
5416d1ee | 833 | PATCH_INDEX (sym->st_shndx); |
4ef37be4 JB |
834 | } |
835 | } | |
836 | } | |
837 | ||
5416d1ee | 838 | /* Close the files and make the new file executable. */ |
4ef37be4 JB |
839 | |
840 | if (close (old_file)) | |
5416d1ee | 841 | fatal ("Can't close (%s): errno %d\n", old_name, errno); |
4ef37be4 JB |
842 | |
843 | if (close (new_file)) | |
5416d1ee | 844 | fatal ("Can't close (%s): errno %d\n", new_name, errno); |
4ef37be4 JB |
845 | |
846 | if (stat (new_name, &stat_buf) == -1) | |
5416d1ee | 847 | fatal ("Can't stat (%s): errno %d\n", new_name, errno); |
4ef37be4 JB |
848 | |
849 | n = umask (777); | |
850 | umask (n); | |
851 | stat_buf.st_mode |= 0111 & ~n; | |
852 | if (chmod (new_name, stat_buf.st_mode) == -1) | |
5416d1ee | 853 | fatal ("Can't chmod (%s): errno %d\n", new_name, errno); |
4ef37be4 | 854 | } |