| 1 | /* Dump an executable image. |
| 2 | Copyright (C) 1985, 1986, 1987, 1988, 1999, 2001, 2002, 2003, 2004, |
| 3 | 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GNU Emacs. |
| 6 | |
| 7 | GNU Emacs is free software: you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation, either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | GNU Emacs is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | /* |
| 21 | In other words, you are welcome to use, share and improve this program. |
| 22 | You are forbidden to forbid anyone else to use, share and improve |
| 23 | what you give them. Help stamp out software-hoarding! */ |
| 24 | |
| 25 | |
| 26 | /* Originally based on the COFF unexec.c by Spencer W. Thomas. |
| 27 | * |
| 28 | * Subsequently hacked on by |
| 29 | * Bill Mann <Bill_Man@praxisint.com> |
| 30 | * Andrew Vignaux <Andrew.Vignaux@comp.vuw.ac.nz> |
| 31 | * Mike Sperber <sperber@informatik.uni-tuebingen.de> |
| 32 | * |
| 33 | * Synopsis: |
| 34 | * unexec (new_name, a_name, data_start, bss_start, entry_address) |
| 35 | * char *new_name, *a_name; |
| 36 | * unsigned data_start, bss_start, entry_address; |
| 37 | * |
| 38 | * Takes a snapshot of the program and makes an a.out format file in the |
| 39 | * file named by the string argument new_name. |
| 40 | * If a_name is non-NULL, the symbol table will be taken from the given file. |
| 41 | * On some machines, an existing a_name file is required. |
| 42 | * |
| 43 | * data_start and entry_address are ignored. |
| 44 | * |
| 45 | * bss_start indicates how much of the data segment is to be saved in the |
| 46 | * a.out file and restored when the program is executed. It gives the lowest |
| 47 | * unsaved address, and is rounded up to a page boundary. The default when 0 |
| 48 | * is given assumes that the entire data segment is to be stored, including |
| 49 | * the previous data and bss as well as any additional storage allocated with |
| 50 | * sbrk(2). |
| 51 | * |
| 52 | */ |
| 53 | |
| 54 | #ifndef emacs |
| 55 | #define PERROR(arg) perror (arg); return -1 |
| 56 | #else |
| 57 | #include <config.h> |
| 58 | #define PERROR(file) report_error (file, new) |
| 59 | #endif |
| 60 | |
| 61 | #include <a.out.h> |
| 62 | /* Define getpagesize () if the system does not. |
| 63 | Note that this may depend on symbols defined in a.out.h |
| 64 | */ |
| 65 | #include "getpagesize.h" |
| 66 | |
| 67 | #include <sys/types.h> |
| 68 | #include <stdio.h> |
| 69 | #include <sys/stat.h> |
| 70 | #include <errno.h> |
| 71 | #include <unistd.h> |
| 72 | #include <fcntl.h> |
| 73 | |
| 74 | char *start_of_text (void); /* Start of text */ |
| 75 | extern char *start_of_data (void); /* Start of initialized data */ |
| 76 | |
| 77 | extern int _data; |
| 78 | extern int _text; |
| 79 | |
| 80 | #include <filehdr.h> |
| 81 | #include <aouthdr.h> |
| 82 | #include <scnhdr.h> |
| 83 | #include <syms.h> |
| 84 | |
| 85 | static struct filehdr f_hdr; /* File header */ |
| 86 | static struct aouthdr f_ohdr; /* Optional file header (a.out) */ |
| 87 | static long bias; /* Bias to add for growth */ |
| 88 | static long lnnoptr; /* Pointer to line-number info within file */ |
| 89 | |
| 90 | static long text_scnptr; |
| 91 | static long data_scnptr; |
| 92 | #define ALIGN(val, pwr) (((val) + ((1L<<(pwr))-1)) & ~((1L<<(pwr))-1)) |
| 93 | static long load_scnptr; |
| 94 | static long orig_load_scnptr; |
| 95 | static long orig_data_scnptr; |
| 96 | static int unrelocate_symbols (int, int, char *, char *); |
| 97 | |
| 98 | #ifndef MAX_SECTIONS |
| 99 | #define MAX_SECTIONS 10 |
| 100 | #endif |
| 101 | |
| 102 | static int adjust_lnnoptrs (int, int, char *); |
| 103 | |
| 104 | static int pagemask; |
| 105 | |
| 106 | #ifdef emacs |
| 107 | #include <setjmp.h> |
| 108 | #include "lisp.h" |
| 109 | |
| 110 | static void |
| 111 | report_error (char *file, int fd) |
| 112 | { |
| 113 | if (fd) |
| 114 | close (fd); |
| 115 | report_file_error ("Cannot unexec", Fcons (build_string (file), Qnil)); |
| 116 | } |
| 117 | #endif /* emacs */ |
| 118 | |
| 119 | #define ERROR0(msg) report_error_1 (new, msg, 0, 0); return -1 |
| 120 | #define ERROR1(msg,x) report_error_1 (new, msg, x, 0); return -1 |
| 121 | #define ERROR2(msg,x,y) report_error_1 (new, msg, x, y); return -1 |
| 122 | |
| 123 | static void |
| 124 | report_error_1 (int fd, char *msg, int a1, int a2) |
| 125 | { |
| 126 | close (fd); |
| 127 | #ifdef emacs |
| 128 | error (msg, a1, a2); |
| 129 | #else |
| 130 | fprintf (stderr, msg, a1, a2); |
| 131 | fprintf (stderr, "\n"); |
| 132 | #endif |
| 133 | } |
| 134 | |
| 135 | static int make_hdr (int, int, unsigned, unsigned, unsigned, char *, char *); |
| 136 | static void mark_x (char *); |
| 137 | static int copy_text_and_data (int); |
| 138 | static int copy_sym (int, int, char *, char *); |
| 139 | static void write_segment (int, char *, char *); |
| 140 | \f |
| 141 | /* **************************************************************** |
| 142 | * unexec |
| 143 | * |
| 144 | * driving logic. |
| 145 | */ |
| 146 | int unexec (char *new_name, char *a_name, |
| 147 | unsigned data_start, |
| 148 | unsigned bss_start, |
| 149 | unsigned entry_address) |
| 150 | { |
| 151 | int new = -1, a_out = -1; |
| 152 | |
| 153 | if (a_name && (a_out = open (a_name, O_RDONLY)) < 0) |
| 154 | { |
| 155 | PERROR (a_name); |
| 156 | } |
| 157 | if ((new = creat (new_name, 0666)) < 0) |
| 158 | { |
| 159 | PERROR (new_name); |
| 160 | } |
| 161 | if (make_hdr (new, a_out, |
| 162 | data_start, bss_start, |
| 163 | entry_address, |
| 164 | a_name, new_name) < 0 |
| 165 | || copy_text_and_data (new) < 0 |
| 166 | || copy_sym (new, a_out, a_name, new_name) < 0 |
| 167 | || adjust_lnnoptrs (new, a_out, new_name) < 0 |
| 168 | || unrelocate_symbols (new, a_out, a_name, new_name) < 0) |
| 169 | { |
| 170 | close (new); |
| 171 | return -1; |
| 172 | } |
| 173 | |
| 174 | close (new); |
| 175 | if (a_out >= 0) |
| 176 | close (a_out); |
| 177 | mark_x (new_name); |
| 178 | return 0; |
| 179 | } |
| 180 | |
| 181 | /* **************************************************************** |
| 182 | * make_hdr |
| 183 | * |
| 184 | * Make the header in the new a.out from the header in core. |
| 185 | * Modify the text and data sizes. |
| 186 | */ |
| 187 | static int |
| 188 | make_hdr (int new, int a_out, |
| 189 | unsigned data_start, unsigned bss_start, |
| 190 | unsigned entry_address, |
| 191 | char *a_name, char *new_name) |
| 192 | { |
| 193 | int scns; |
| 194 | unsigned int bss_end; |
| 195 | |
| 196 | struct scnhdr section[MAX_SECTIONS]; |
| 197 | struct scnhdr * f_thdr; /* Text section header */ |
| 198 | struct scnhdr * f_dhdr; /* Data section header */ |
| 199 | struct scnhdr * f_bhdr; /* Bss section header */ |
| 200 | struct scnhdr * f_lhdr; /* Loader section header */ |
| 201 | struct scnhdr * f_tchdr; /* Typechk section header */ |
| 202 | struct scnhdr * f_dbhdr; /* Debug section header */ |
| 203 | struct scnhdr * f_xhdr; /* Except section header */ |
| 204 | |
| 205 | load_scnptr = orig_load_scnptr = lnnoptr = 0; |
| 206 | pagemask = getpagesize () - 1; |
| 207 | |
| 208 | /* Adjust text/data boundary. */ |
| 209 | data_start = (long) start_of_data (); |
| 210 | data_start = ADDR_CORRECT (data_start); |
| 211 | |
| 212 | data_start = data_start & ~pagemask; /* (Down) to page boundary. */ |
| 213 | |
| 214 | bss_end = ADDR_CORRECT (sbrk (0)) + pagemask; |
| 215 | bss_end &= ~ pagemask; |
| 216 | /* Adjust data/bss boundary. */ |
| 217 | if (bss_start != 0) |
| 218 | { |
| 219 | bss_start = (ADDR_CORRECT (bss_start) + pagemask); |
| 220 | /* (Up) to page bdry. */ |
| 221 | bss_start &= ~ pagemask; |
| 222 | if (bss_start > bss_end) |
| 223 | { |
| 224 | ERROR1 ("unexec: Specified bss_start (%u) is past end of program", |
| 225 | bss_start); |
| 226 | } |
| 227 | } |
| 228 | else |
| 229 | bss_start = bss_end; |
| 230 | |
| 231 | if (data_start > bss_start) /* Can't have negative data size. */ |
| 232 | { |
| 233 | ERROR2 ("unexec: data_start (%u) can't be greater than bss_start (%u)", |
| 234 | data_start, bss_start); |
| 235 | } |
| 236 | |
| 237 | /* Salvage as much info from the existing file as possible */ |
| 238 | f_thdr = NULL; f_dhdr = NULL; f_bhdr = NULL; |
| 239 | f_lhdr = NULL; f_tchdr = NULL; f_dbhdr = NULL; f_xhdr = NULL; |
| 240 | if (a_out >= 0) |
| 241 | { |
| 242 | if (read (a_out, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr)) |
| 243 | { |
| 244 | PERROR (a_name); |
| 245 | } |
| 246 | if (f_hdr.f_opthdr > 0) |
| 247 | { |
| 248 | if (read (a_out, &f_ohdr, sizeof (f_ohdr)) != sizeof (f_ohdr)) |
| 249 | { |
| 250 | PERROR (a_name); |
| 251 | } |
| 252 | } |
| 253 | if (f_hdr.f_nscns > MAX_SECTIONS) |
| 254 | { |
| 255 | ERROR0 ("unexec: too many section headers -- increase MAX_SECTIONS"); |
| 256 | } |
| 257 | /* Loop through section headers */ |
| 258 | for (scns = 0; scns < f_hdr.f_nscns; scns++) { |
| 259 | struct scnhdr *s = §ion[scns]; |
| 260 | if (read (a_out, s, sizeof (*s)) != sizeof (*s)) |
| 261 | { |
| 262 | PERROR (a_name); |
| 263 | } |
| 264 | |
| 265 | #define CHECK_SCNHDR(ptr, name, flags) \ |
| 266 | if (strcmp(s->s_name, name) == 0) { \ |
| 267 | if (s->s_flags != flags) { \ |
| 268 | fprintf(stderr, "unexec: %lx flags where %x expected in %s section.\n", \ |
| 269 | (unsigned long)s->s_flags, flags, name); \ |
| 270 | } \ |
| 271 | if (ptr) { \ |
| 272 | fprintf(stderr, "unexec: duplicate section header for section %s.\n", \ |
| 273 | name); \ |
| 274 | } \ |
| 275 | ptr = s; \ |
| 276 | } |
| 277 | CHECK_SCNHDR(f_thdr, _TEXT, STYP_TEXT); |
| 278 | CHECK_SCNHDR(f_dhdr, _DATA, STYP_DATA); |
| 279 | CHECK_SCNHDR(f_bhdr, _BSS, STYP_BSS); |
| 280 | CHECK_SCNHDR(f_lhdr, _LOADER, STYP_LOADER); |
| 281 | CHECK_SCNHDR(f_dbhdr, _DEBUG, STYP_DEBUG); |
| 282 | CHECK_SCNHDR(f_tchdr, _TYPCHK, STYP_TYPCHK); |
| 283 | CHECK_SCNHDR(f_xhdr, _EXCEPT, STYP_EXCEPT); |
| 284 | } |
| 285 | |
| 286 | if (f_thdr == 0) |
| 287 | { |
| 288 | ERROR1 ("unexec: couldn't find \"%s\" section", (int) _TEXT); |
| 289 | } |
| 290 | if (f_dhdr == 0) |
| 291 | { |
| 292 | ERROR1 ("unexec: couldn't find \"%s\" section", (int) _DATA); |
| 293 | } |
| 294 | if (f_bhdr == 0) |
| 295 | { |
| 296 | ERROR1 ("unexec: couldn't find \"%s\" section", (int) _BSS); |
| 297 | } |
| 298 | } |
| 299 | else |
| 300 | { |
| 301 | ERROR0 ("can't build a COFF file from scratch yet"); |
| 302 | } |
| 303 | orig_data_scnptr = f_dhdr->s_scnptr; |
| 304 | orig_load_scnptr = f_lhdr ? f_lhdr->s_scnptr : 0; |
| 305 | |
| 306 | /* Now we alter the contents of all the f_*hdr variables |
| 307 | to correspond to what we want to dump. */ |
| 308 | |
| 309 | /* Indicate that the reloc information is no longer valid for ld (bind); |
| 310 | we only update it enough to fake out the exec-time loader. */ |
| 311 | f_hdr.f_flags |= (F_RELFLG | F_EXEC); |
| 312 | |
| 313 | f_ohdr.dsize = bss_start - f_ohdr.data_start; |
| 314 | f_ohdr.bsize = bss_end - bss_start; |
| 315 | |
| 316 | f_dhdr->s_size = f_ohdr.dsize; |
| 317 | f_bhdr->s_size = f_ohdr.bsize; |
| 318 | f_bhdr->s_paddr = f_ohdr.data_start + f_ohdr.dsize; |
| 319 | f_bhdr->s_vaddr = f_ohdr.data_start + f_ohdr.dsize; |
| 320 | |
| 321 | /* fix scnptr's */ |
| 322 | { |
| 323 | ulong ptr = section[0].s_scnptr; |
| 324 | |
| 325 | bias = -1; |
| 326 | for (scns = 0; scns < f_hdr.f_nscns; scns++) |
| 327 | { |
| 328 | struct scnhdr *s = §ion[scns]; |
| 329 | |
| 330 | if (s->s_flags & STYP_PAD) /* .pad sections omitted in AIX 4.1 */ |
| 331 | { |
| 332 | /* |
| 333 | * the text_start should probably be o_algntext but that doesn't |
| 334 | * seem to change |
| 335 | */ |
| 336 | if (f_ohdr.text_start != 0) /* && scns != 0 */ |
| 337 | { |
| 338 | s->s_size = 512 - (ptr % 512); |
| 339 | if (s->s_size == 512) |
| 340 | s->s_size = 0; |
| 341 | } |
| 342 | s->s_scnptr = ptr; |
| 343 | } |
| 344 | else if (s->s_flags & STYP_DATA) |
| 345 | s->s_scnptr = ptr; |
| 346 | else if (!(s->s_flags & (STYP_TEXT | STYP_BSS))) |
| 347 | { |
| 348 | if (bias == -1) /* if first section after bss */ |
| 349 | bias = ptr - s->s_scnptr; |
| 350 | |
| 351 | s->s_scnptr += bias; |
| 352 | ptr = s->s_scnptr; |
| 353 | } |
| 354 | |
| 355 | ptr = ptr + s->s_size; |
| 356 | } |
| 357 | } |
| 358 | |
| 359 | /* fix other pointers */ |
| 360 | for (scns = 0; scns < f_hdr.f_nscns; scns++) |
| 361 | { |
| 362 | struct scnhdr *s = §ion[scns]; |
| 363 | |
| 364 | if (s->s_relptr != 0) |
| 365 | { |
| 366 | s->s_relptr += bias; |
| 367 | } |
| 368 | if (s->s_lnnoptr != 0) |
| 369 | { |
| 370 | if (lnnoptr == 0) lnnoptr = s->s_lnnoptr; |
| 371 | s->s_lnnoptr += bias; |
| 372 | } |
| 373 | } |
| 374 | |
| 375 | if (f_hdr.f_symptr > 0L) |
| 376 | { |
| 377 | f_hdr.f_symptr += bias; |
| 378 | } |
| 379 | |
| 380 | text_scnptr = f_thdr->s_scnptr; |
| 381 | data_scnptr = f_dhdr->s_scnptr; |
| 382 | load_scnptr = f_lhdr ? f_lhdr->s_scnptr : 0; |
| 383 | |
| 384 | if (write (new, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr)) |
| 385 | { |
| 386 | PERROR (new_name); |
| 387 | } |
| 388 | |
| 389 | if (f_hdr.f_opthdr > 0) |
| 390 | { |
| 391 | if (write (new, &f_ohdr, sizeof (f_ohdr)) != sizeof (f_ohdr)) |
| 392 | { |
| 393 | PERROR (new_name); |
| 394 | } |
| 395 | } |
| 396 | |
| 397 | for (scns = 0; scns < f_hdr.f_nscns; scns++) { |
| 398 | struct scnhdr *s = §ion[scns]; |
| 399 | if (write (new, s, sizeof (*s)) != sizeof (*s)) |
| 400 | { |
| 401 | PERROR (new_name); |
| 402 | } |
| 403 | } |
| 404 | |
| 405 | return (0); |
| 406 | } |
| 407 | \f |
| 408 | /* **************************************************************** |
| 409 | |
| 410 | * |
| 411 | * Copy the text and data segments from memory to the new a.out |
| 412 | */ |
| 413 | static int |
| 414 | copy_text_and_data (int new) |
| 415 | { |
| 416 | char *end; |
| 417 | char *ptr; |
| 418 | |
| 419 | lseek (new, (long) text_scnptr, SEEK_SET); |
| 420 | ptr = start_of_text () + text_scnptr; |
| 421 | end = ptr + f_ohdr.tsize; |
| 422 | write_segment (new, ptr, end); |
| 423 | |
| 424 | lseek (new, (long) data_scnptr, SEEK_SET); |
| 425 | ptr = (char *) f_ohdr.data_start; |
| 426 | end = ptr + f_ohdr.dsize; |
| 427 | write_segment (new, ptr, end); |
| 428 | |
| 429 | return 0; |
| 430 | } |
| 431 | |
| 432 | #define UnexBlockSz (1<<12) /* read/write block size */ |
| 433 | static void |
| 434 | write_segment (int new, char *ptr, char *end) |
| 435 | { |
| 436 | int i, nwrite, ret; |
| 437 | char buf[80]; |
| 438 | char zeros[UnexBlockSz]; |
| 439 | |
| 440 | for (i = 0; ptr < end;) |
| 441 | { |
| 442 | /* distance to next block. */ |
| 443 | nwrite = (((int) ptr + UnexBlockSz) & -UnexBlockSz) - (int) ptr; |
| 444 | /* But not beyond specified end. */ |
| 445 | if (nwrite > end - ptr) nwrite = end - ptr; |
| 446 | ret = write (new, ptr, nwrite); |
| 447 | /* If write gets a page fault, it means we reached |
| 448 | a gap between the old text segment and the old data segment. |
| 449 | This gap has probably been remapped into part of the text segment. |
| 450 | So write zeros for it. */ |
| 451 | if (ret == -1 && errno == EFAULT) |
| 452 | { |
| 453 | memset (zeros, 0, nwrite); |
| 454 | write (new, zeros, nwrite); |
| 455 | } |
| 456 | else if (nwrite != ret) |
| 457 | { |
| 458 | sprintf (buf, |
| 459 | "unexec write failure: addr 0x%lx, fileno %d, size 0x%x, wrote 0x%x, errno %d", |
| 460 | (unsigned long)ptr, new, nwrite, ret, errno); |
| 461 | PERROR (buf); |
| 462 | } |
| 463 | i += nwrite; |
| 464 | ptr += nwrite; |
| 465 | } |
| 466 | } |
| 467 | \f |
| 468 | /* **************************************************************** |
| 469 | * copy_sym |
| 470 | * |
| 471 | * Copy the relocation information and symbol table from the a.out to the new |
| 472 | */ |
| 473 | static int |
| 474 | copy_sym (int new, int a_out, char *a_name, char *new_name) |
| 475 | { |
| 476 | char page[UnexBlockSz]; |
| 477 | int n; |
| 478 | |
| 479 | if (a_out < 0) |
| 480 | return 0; |
| 481 | |
| 482 | if (orig_load_scnptr == 0L) |
| 483 | return 0; |
| 484 | |
| 485 | if (lnnoptr && lnnoptr < orig_load_scnptr) /* if there is line number info */ |
| 486 | lseek (a_out, lnnoptr, SEEK_SET); /* start copying from there */ |
| 487 | else |
| 488 | lseek (a_out, orig_load_scnptr, SEEK_SET); /* Position a.out to symtab. */ |
| 489 | |
| 490 | while ((n = read (a_out, page, sizeof page)) > 0) |
| 491 | { |
| 492 | if (write (new, page, n) != n) |
| 493 | { |
| 494 | PERROR (new_name); |
| 495 | } |
| 496 | } |
| 497 | if (n < 0) |
| 498 | { |
| 499 | PERROR (a_name); |
| 500 | } |
| 501 | return 0; |
| 502 | } |
| 503 | \f |
| 504 | /* **************************************************************** |
| 505 | * mark_x |
| 506 | * |
| 507 | * After successfully building the new a.out, mark it executable |
| 508 | */ |
| 509 | static void |
| 510 | mark_x (char *name) |
| 511 | { |
| 512 | struct stat sbuf; |
| 513 | int um; |
| 514 | int new = 0; /* for PERROR */ |
| 515 | |
| 516 | um = umask (777); |
| 517 | umask (um); |
| 518 | if (stat (name, &sbuf) == -1) |
| 519 | { |
| 520 | PERROR (name); |
| 521 | } |
| 522 | sbuf.st_mode |= 0111 & ~um; |
| 523 | if (chmod (name, sbuf.st_mode) == -1) |
| 524 | PERROR (name); |
| 525 | } |
| 526 | \f |
| 527 | static int |
| 528 | adjust_lnnoptrs (int writedesc, int readdesc, char *new_name) |
| 529 | { |
| 530 | int nsyms; |
| 531 | int naux; |
| 532 | int new; |
| 533 | struct syment symentry; |
| 534 | union auxent auxentry; |
| 535 | |
| 536 | if (!lnnoptr || !f_hdr.f_symptr) |
| 537 | return 0; |
| 538 | |
| 539 | if ((new = open (new_name, O_RDWR)) < 0) |
| 540 | { |
| 541 | PERROR (new_name); |
| 542 | return -1; |
| 543 | } |
| 544 | |
| 545 | lseek (new, f_hdr.f_symptr, SEEK_SET); |
| 546 | for (nsyms = 0; nsyms < f_hdr.f_nsyms; nsyms++) |
| 547 | { |
| 548 | read (new, &symentry, SYMESZ); |
| 549 | if (symentry.n_sclass == C_BINCL || symentry.n_sclass == C_EINCL) |
| 550 | { |
| 551 | symentry.n_value += bias; |
| 552 | lseek (new, -SYMESZ, SEEK_CUR); |
| 553 | write (new, &symentry, SYMESZ); |
| 554 | } |
| 555 | |
| 556 | for (naux = symentry.n_numaux; naux-- != 0; ) |
| 557 | { |
| 558 | read (new, &auxentry, AUXESZ); |
| 559 | nsyms++; |
| 560 | if (naux != 0 /* skip csect auxentry (last entry) */ |
| 561 | && (symentry.n_sclass == C_EXT || symentry.n_sclass == C_HIDEXT)) |
| 562 | { |
| 563 | auxentry.x_sym.x_fcnary.x_fcn.x_lnnoptr += bias; |
| 564 | lseek (new, -AUXESZ, SEEK_CUR); |
| 565 | write (new, &auxentry, AUXESZ); |
| 566 | } |
| 567 | } |
| 568 | } |
| 569 | close (new); |
| 570 | |
| 571 | return 0; |
| 572 | } |
| 573 | |
| 574 | static int |
| 575 | unrelocate_symbols (int new, int a_out, char *a_name, char *new_name) |
| 576 | { |
| 577 | int i; |
| 578 | LDHDR ldhdr; |
| 579 | LDREL ldrel; |
| 580 | ulong t_reloc = (ulong) &_text - f_ohdr.text_start; |
| 581 | #ifndef ALIGN_DATA_RELOC |
| 582 | ulong d_reloc = (ulong) &_data - f_ohdr.data_start; |
| 583 | #else |
| 584 | /* This worked (and was needed) before AIX 4.2. |
| 585 | I have no idea why. -- Mike */ |
| 586 | ulong d_reloc = (ulong) &_data - ALIGN(f_ohdr.data_start, 2); |
| 587 | #endif |
| 588 | int * p; |
| 589 | |
| 590 | if (load_scnptr == 0) |
| 591 | return 0; |
| 592 | |
| 593 | lseek (a_out, orig_load_scnptr, SEEK_SET); |
| 594 | if (read (a_out, &ldhdr, sizeof (ldhdr)) != sizeof (ldhdr)) |
| 595 | { |
| 596 | PERROR (new_name); |
| 597 | } |
| 598 | |
| 599 | #define SYMNDX_TEXT 0 |
| 600 | #define SYMNDX_DATA 1 |
| 601 | #define SYMNDX_BSS 2 |
| 602 | |
| 603 | for (i = 0; i < ldhdr.l_nreloc; i++) |
| 604 | { |
| 605 | lseek (a_out, |
| 606 | orig_load_scnptr + LDHDRSZ + LDSYMSZ*ldhdr.l_nsyms + LDRELSZ*i, |
| 607 | SEEK_SET); |
| 608 | |
| 609 | if (read (a_out, &ldrel, LDRELSZ) != LDRELSZ) |
| 610 | { |
| 611 | PERROR (a_name); |
| 612 | } |
| 613 | |
| 614 | /* move the BSS loader symbols to the DATA segment */ |
| 615 | if (ldrel.l_symndx == SYMNDX_BSS) |
| 616 | { |
| 617 | ldrel.l_symndx = SYMNDX_DATA; |
| 618 | |
| 619 | lseek (new, |
| 620 | load_scnptr + LDHDRSZ + LDSYMSZ*ldhdr.l_nsyms + LDRELSZ*i, |
| 621 | SEEK_SET); |
| 622 | |
| 623 | if (write (new, &ldrel, LDRELSZ) != LDRELSZ) |
| 624 | { |
| 625 | PERROR (new_name); |
| 626 | } |
| 627 | } |
| 628 | |
| 629 | if (ldrel.l_rsecnm == f_ohdr.o_sndata) |
| 630 | { |
| 631 | int orig_int; |
| 632 | |
| 633 | lseek (a_out, |
| 634 | orig_data_scnptr + (ldrel.l_vaddr - f_ohdr.data_start), |
| 635 | SEEK_SET); |
| 636 | |
| 637 | if (read (a_out, (void *) &orig_int, sizeof (orig_int)) |
| 638 | != sizeof (orig_int)) |
| 639 | { |
| 640 | PERROR (a_name); |
| 641 | } |
| 642 | |
| 643 | p = (int *) (ldrel.l_vaddr + d_reloc); |
| 644 | |
| 645 | switch (ldrel.l_symndx) { |
| 646 | case SYMNDX_TEXT: |
| 647 | orig_int = * p - t_reloc; |
| 648 | break; |
| 649 | |
| 650 | case SYMNDX_DATA: |
| 651 | case SYMNDX_BSS: |
| 652 | orig_int = * p - d_reloc; |
| 653 | break; |
| 654 | } |
| 655 | |
| 656 | if (orig_int != * p) |
| 657 | { |
| 658 | lseek (new, |
| 659 | data_scnptr + (ldrel.l_vaddr - f_ohdr.data_start), |
| 660 | SEEK_SET); |
| 661 | if (write (new, (void *) &orig_int, sizeof (orig_int)) |
| 662 | != sizeof (orig_int)) |
| 663 | { |
| 664 | PERROR (new_name); |
| 665 | } |
| 666 | } |
| 667 | } |
| 668 | } |
| 669 | return 0; |
| 670 | } |
| 671 | |
| 672 | /* |
| 673 | * Return the address of the start of the text segment prior to |
| 674 | * doing an unexec. After unexec the return value is undefined. |
| 675 | * See crt0.c for further explanation and _start. |
| 676 | * |
| 677 | */ |
| 678 | |
| 679 | char * |
| 680 | start_of_text (void) |
| 681 | { |
| 682 | return ((char *) 0x10000000); |
| 683 | } |
| 684 | |
| 685 | /* arch-tag: 0783857a-7c2d-456f-a426-58b722d69fd0 |
| 686 | (do not change this comment) */ |