1 /* simple-object-coff.c -- routines to manipulate XCOFF object files. 2 Copyright 2013 Free Software Foundation, Inc. 3 Written by Ian Lance Taylor, Google and David Edelsohn, IBM. 4 5 This program is free software; you can redistribute it and/or modify it 6 under the terms of the GNU General Public License as published by the 7 Free Software Foundation; either version 2, or (at your option) any 8 later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program; if not, write to the Free Software 17 Foundation, 51 Franklin Street - Fifth Floor, 18 Boston, MA 02110-1301, USA. */ 19 20 #include "config.h" 21 #include "libiberty.h" 22 #include "simple-object.h" 23 24 #include <errno.h> 25 #include <stddef.h> 26 27 #ifdef HAVE_STDLIB_H 28 #include <stdlib.h> 29 #endif 30 31 #ifdef HAVE_STDINT_H 32 #include <stdint.h> 33 #endif 34 35 #ifdef HAVE_STRING_H 36 #include <string.h> 37 #endif 38 39 #ifdef HAVE_INTTYPES_H 40 #include <inttypes.h> 41 #endif 42 43 #include "simple-object-common.h" 44 45 /* XCOFF structures and constants. */ 46 47 /* XCOFF file header. */ 48 49 struct external_filehdr 50 { 51 unsigned char f_magic[2]; /* magic number */ 52 unsigned char f_nscns[2]; /* number of sections */ 53 unsigned char f_timdat[4]; /* time & date stamp */ 54 union 55 { 56 struct 57 { 58 unsigned char f_symptr[4]; /* file pointer to symtab */ 59 unsigned char f_nsyms[4]; /* number of symtab entries */ 60 unsigned char f_opthdr[2]; /* sizeof(optional hdr) */ 61 unsigned char f_flags[2]; /* flags */ 62 } xcoff32; 63 struct 64 { 65 unsigned char f_symptr[8]; /* file pointer to symtab */ 66 unsigned char f_opthdr[2]; /* sizeof(optional hdr) */ 67 unsigned char f_flags[2]; /* flags */ 68 unsigned char f_nsyms[4]; /* number of symtab entries */ 69 } xcoff64; 70 } u; 71 }; 72 73 /* Bits for filehdr f_flags field. */ 74 75 #define F_EXEC (0x0002) 76 77 /* The known values of f_magic in an XCOFF file header. */ 78 79 #define U802WRMAGIC 0730 /* Writeable text segments. */ 80 #define U802ROMAGIC 0735 /* Readonly sharable text segments. */ 81 #define U802TOCMAGIC 0737 /* Readonly text segments and TOC. */ 82 #define U803XTOCMAGIC 0757 /* Aix 4.3 64-bit XCOFF. */ 83 #define U64_TOCMAGIC 0767 /* AIX 5+ 64-bit XCOFF. */ 84 85 /* XCOFF section header. */ 86 87 struct external_scnhdr 88 { 89 unsigned char s_name[8]; /* section name */ 90 union 91 { 92 struct 93 { 94 unsigned char s_paddr[4]; /* physical address, aliased s_nlib */ 95 unsigned char s_vaddr[4]; /* virtual address */ 96 unsigned char s_size[4]; /* section size */ 97 unsigned char s_scnptr[4]; /* file ptr to raw data for section */ 98 unsigned char s_relptr[4]; /* file ptr to relocation */ 99 unsigned char s_lnnoptr[4]; /* file ptr to line numbers */ 100 unsigned char s_nreloc[2]; /* number of relocation entries */ 101 unsigned char s_nlnno[2]; /* number of line number entries */ 102 unsigned char s_flags[4]; /* flags */ 103 } xcoff32; 104 struct 105 { 106 unsigned char s_paddr[8]; /* physical address, aliased s_nlib */ 107 unsigned char s_vaddr[8]; /* virtual address */ 108 unsigned char s_size[8]; /* section size */ 109 unsigned char s_scnptr[8]; /* file ptr to raw data for section */ 110 unsigned char s_relptr[8]; /* file ptr to relocation */ 111 unsigned char s_lnnoptr[8]; /* file ptr to line numbers */ 112 unsigned char s_nreloc[4]; /* number of relocation entries */ 113 unsigned char s_nlnno[4]; /* number of line number entries */ 114 unsigned char s_flags[4]; /* flags */ 115 } xcoff64; 116 } u; 117 }; 118 119 #define SCNHSZ32 (40) 120 #define SCNHSZ64 (68) 121 122 /* The length of the s_name field in struct external_scnhdr. */ 123 124 #define SCNNMLEN (8) 125 126 /* Bits for scnhdr s_flags field. */ 127 128 #define STYP_DATA 0x40 129 130 /* XCOFF symbol table entry. */ 131 132 133 #define N_SYMNMLEN (8) /* # characters in a symbol name */ 134 135 /* The format of an XCOFF symbol-table entry. */ 136 struct external_syment 137 { 138 union { 139 struct { 140 union { 141 /* The name of the symbol. There is an implicit null character 142 after the end of the array. */ 143 char n_name[N_SYMNMLEN]; 144 struct { 145 /* If n_zeroes is zero, n_offset is the offset the name from 146 the start of the string table. */ 147 unsigned char n_zeroes[4]; 148 unsigned char n_offset[4]; 149 } n; 150 } n; 151 152 /* The symbol's value. */ 153 unsigned char n_value[4]; 154 } xcoff32; 155 struct { 156 /* The symbol's value. */ 157 unsigned char n_value[8]; 158 159 /* The offset of the symbol from the start of the string table. */ 160 unsigned char n_offset[4]; 161 } xcoff64; 162 } u; 163 164 /* The number of the section to which this symbol belongs. */ 165 unsigned char n_scnum[2]; 166 167 /* The type of symbol. (It can be interpreted as an n_lang 168 and an n_cpu byte, but we don't care about that here.) */ 169 unsigned char n_type[2]; 170 171 /* The class of symbol (a C_* value). */ 172 unsigned char n_sclass[1]; 173 174 /* The number of auxiliary symbols attached to this entry. */ 175 unsigned char n_numaux[1]; 176 }; 177 178 #define SYMESZ (18) 179 180 /* Length allowed for filename in aux sym format 4. */ 181 182 #define FILNMLEN (14) 183 184 /* Omits x_sym and other unused variants. */ 185 186 union external_auxent 187 { 188 /* Aux sym format 4: file. */ 189 union 190 { 191 char x_fname[FILNMLEN]; 192 struct 193 { 194 unsigned char x_zeroes[4]; 195 unsigned char x_offset[4]; 196 unsigned char x_pad[FILNMLEN-8]; 197 unsigned char x_ftype; 198 } _x; 199 } x_file; 200 /* Aux sym format 5: section. */ 201 struct 202 { 203 unsigned char x_scnlen[4]; /* section length */ 204 unsigned char x_nreloc[2]; /* # relocation entries */ 205 unsigned char x_nlinno[2]; /* # line numbers */ 206 } x_scn; 207 /* CSECT auxiliary entry. */ 208 union 209 { 210 struct 211 { 212 struct 213 { 214 unsigned char x_scnlen[4]; /* csect length */ 215 unsigned char x_parmhash[4]; /* parm type hash index */ 216 unsigned char x_snhash[2]; /* sect num with parm hash */ 217 unsigned char x_smtyp; /* symbol align and type */ 218 unsigned char x_smclas; /* storage mapping class */ 219 unsigned char x_stab; /* dbx stab info index */ 220 unsigned char x_snstab[2]; /* sect num with dbx stab */ 221 } x_csect; 222 } xcoff32; 223 struct 224 { 225 struct 226 { 227 unsigned char x_scnlen_lo[4]; /* csect length */ 228 unsigned char x_parmhash[4]; /* parm type hash index */ 229 unsigned char x_snhash[2]; /* sect num with parm hash */ 230 unsigned char x_smtyp; /* symbol align and type */ 231 unsigned char x_smclas; /* storage mapping class */ 232 unsigned char x_scnlen_hi[4]; 233 unsigned char pad; 234 unsigned char x_auxtype; 235 } x_csect; 236 } xcoff64; 237 } u; 238 /* SECTION/DWARF auxiliary entry. */ 239 struct 240 { 241 unsigned char x_scnlen[4]; /* section length */ 242 unsigned char pad1[4]; 243 unsigned char x_nreloc[4]; /* number RLDs */ 244 } x_sect; 245 }; 246 247 /* Symbol-related constants. */ 248 249 #define N_DEBUG (-2) 250 #define IMAGE_SYM_TYPE_NULL (0) 251 #define IMAGE_SYM_DTYPE_NULL (0) 252 #define IMAGE_SYM_CLASS_STATIC (3) 253 #define IMAGE_SYM_CLASS_FILE (103) 254 255 #define IMAGE_SYM_TYPE \ 256 ((IMAGE_SYM_DTYPE_NULL << 4) | IMAGE_SYM_TYPE_NULL) 257 258 #define C_STAT (3) 259 #define C_FILE (103) 260 261 /* Private data for an simple_object_read. */ 262 263 struct simple_object_xcoff_read 264 { 265 /* Magic number. */ 266 unsigned short magic; 267 /* Number of sections. */ 268 unsigned short nscns; 269 /* File offset of symbol table. */ 270 off_t symptr; 271 /* Number of symbol table entries. */ 272 unsigned int nsyms; 273 /* Flags. */ 274 unsigned short flags; 275 /* Offset of section headers in file. */ 276 off_t scnhdr_offset; 277 }; 278 279 /* Private data for an simple_object_attributes. */ 280 281 struct simple_object_xcoff_attributes 282 { 283 /* Magic number. */ 284 unsigned short magic; 285 /* Flags. */ 286 unsigned short flags; 287 }; 288 289 /* See if we have a XCOFF file. */ 290 291 static void * 292 simple_object_xcoff_match (unsigned char header[SIMPLE_OBJECT_MATCH_HEADER_LEN], 293 int descriptor, off_t offset, 294 const char *segment_name ATTRIBUTE_UNUSED, 295 const char **errmsg, int *err) 296 { 297 unsigned short magic; 298 unsigned short (*fetch_16) (const unsigned char *); 299 unsigned int (*fetch_32) (const unsigned char *); 300 ulong_type (*fetch_64) (const unsigned char *); 301 unsigned char hdrbuf[sizeof (struct external_filehdr)]; 302 struct simple_object_xcoff_read *ocr; 303 int u64; 304 305 magic = simple_object_fetch_big_16 (header); 306 307 if (magic != U802TOCMAGIC && magic != U64_TOCMAGIC) 308 { 309 *errmsg = NULL; 310 *err = 0; 311 return NULL; 312 } 313 314 fetch_16 = simple_object_fetch_big_16; 315 fetch_32 = simple_object_fetch_big_32; 316 fetch_64 = simple_object_fetch_big_64; 317 318 if (!simple_object_internal_read (descriptor, offset, hdrbuf, sizeof hdrbuf, 319 errmsg, err)) 320 return NULL; 321 322 u64 = magic == U64_TOCMAGIC; 323 324 ocr = XNEW (struct simple_object_xcoff_read); 325 ocr->magic = magic; 326 ocr->nscns = fetch_16 (hdrbuf + offsetof (struct external_filehdr, f_nscns)); 327 if (u64) 328 { 329 ocr->symptr = fetch_64 (hdrbuf 330 + offsetof (struct external_filehdr, 331 u.xcoff64.f_symptr)); 332 ocr->nsyms = fetch_32 (hdrbuf + offsetof (struct external_filehdr, 333 u.xcoff64.f_nsyms)); 334 ocr->scnhdr_offset = (sizeof (struct external_filehdr) 335 + fetch_16 (hdrbuf + offsetof (struct external_filehdr, 336 u.xcoff64.f_opthdr))); 337 338 } 339 else 340 { 341 ocr->symptr = fetch_32 (hdrbuf 342 + offsetof (struct external_filehdr, 343 u.xcoff32.f_symptr)); 344 ocr->nsyms = fetch_32 (hdrbuf + offsetof (struct external_filehdr, 345 u.xcoff32.f_nsyms)); 346 ocr->scnhdr_offset = (sizeof (struct external_filehdr) - 4 347 + fetch_16 (hdrbuf + offsetof (struct external_filehdr, 348 u.xcoff32.f_opthdr))); 349 350 } 351 352 return (void *) ocr; 353 } 354 355 /* Read the string table in a XCOFF file. */ 356 357 static char * 358 simple_object_xcoff_read_strtab (simple_object_read *sobj, size_t *strtab_size, 359 const char **errmsg, int *err) 360 { 361 struct simple_object_xcoff_read *ocr = 362 (struct simple_object_xcoff_read *) sobj->data; 363 off_t strtab_offset; 364 unsigned char strsizebuf[4]; 365 size_t strsize; 366 char *strtab; 367 368 strtab_offset = sobj->offset + ocr->symptr 369 + ocr->nsyms * SYMESZ; 370 if (!simple_object_internal_read (sobj->descriptor, strtab_offset, 371 strsizebuf, 4, errmsg, err)) 372 return NULL; 373 strsize = simple_object_fetch_big_32 (strsizebuf); 374 strtab = XNEWVEC (char, strsize); 375 if (!simple_object_internal_read (sobj->descriptor, strtab_offset, 376 (unsigned char *) strtab, strsize, errmsg, 377 err)) 378 { 379 XDELETEVEC (strtab); 380 return NULL; 381 } 382 *strtab_size = strsize; 383 return strtab; 384 } 385 386 /* Find all sections in a XCOFF file. */ 387 388 static const char * 389 simple_object_xcoff_find_sections (simple_object_read *sobj, 390 int (*pfn) (void *, const char *, 391 off_t offset, off_t length), 392 void *data, 393 int *err) 394 { 395 struct simple_object_xcoff_read *ocr = 396 (struct simple_object_xcoff_read *) sobj->data; 397 int u64 = ocr->magic == U64_TOCMAGIC; 398 size_t scnhdr_size; 399 unsigned char *scnbuf; 400 const char *errmsg; 401 unsigned int (*fetch_32) (const unsigned char *); 402 ulong_type (*fetch_64) (const unsigned char *); 403 unsigned int nscns; 404 char *strtab; 405 size_t strtab_size; 406 unsigned int i; 407 408 scnhdr_size = u64 ? SCNHSZ64 : SCNHSZ32; 409 scnbuf = XNEWVEC (unsigned char, scnhdr_size * ocr->nscns); 410 if (!simple_object_internal_read (sobj->descriptor, 411 sobj->offset + ocr->scnhdr_offset, 412 scnbuf, scnhdr_size * ocr->nscns, &errmsg, 413 err)) 414 { 415 XDELETEVEC (scnbuf); 416 return errmsg; 417 } 418 419 fetch_32 = simple_object_fetch_big_32; 420 fetch_64 = simple_object_fetch_big_64; 421 422 nscns = ocr->nscns; 423 strtab = NULL; 424 strtab_size = 0; 425 for (i = 0; i < nscns; ++i) 426 { 427 unsigned char *scnhdr; 428 unsigned char *scnname; 429 char namebuf[SCNNMLEN + 1]; 430 char *name; 431 off_t scnptr; 432 unsigned int size; 433 434 scnhdr = scnbuf + i * scnhdr_size; 435 scnname = scnhdr + offsetof (struct external_scnhdr, s_name); 436 memcpy (namebuf, scnname, SCNNMLEN); 437 namebuf[SCNNMLEN] = '\0'; 438 name = &namebuf[0]; 439 if (namebuf[0] == '/') 440 { 441 size_t strindex; 442 char *end; 443 444 strindex = strtol (namebuf + 1, &end, 10); 445 if (*end == '\0') 446 { 447 /* The real section name is found in the string 448 table. */ 449 if (strtab == NULL) 450 { 451 strtab = simple_object_xcoff_read_strtab (sobj, 452 &strtab_size, 453 &errmsg, err); 454 if (strtab == NULL) 455 { 456 XDELETEVEC (scnbuf); 457 return errmsg; 458 } 459 } 460 461 if (strindex < 4 || strindex >= strtab_size) 462 { 463 XDELETEVEC (strtab); 464 XDELETEVEC (scnbuf); 465 *err = 0; 466 return "section string index out of range"; 467 } 468 469 name = strtab + strindex; 470 } 471 } 472 473 if (u64) 474 { 475 scnptr = fetch_64 (scnhdr + offsetof (struct external_scnhdr, 476 u.xcoff64.s_scnptr)); 477 size = fetch_64 (scnhdr + offsetof (struct external_scnhdr, 478 u.xcoff64.s_size)); 479 } 480 else 481 { 482 scnptr = fetch_32 (scnhdr + offsetof (struct external_scnhdr, 483 u.xcoff32.s_scnptr)); 484 size = fetch_32 (scnhdr + offsetof (struct external_scnhdr, 485 u.xcoff32.s_size)); 486 } 487 488 if (!(*pfn) (data, name, scnptr, size)) 489 break; 490 } 491 492 if (strtab != NULL) 493 XDELETEVEC (strtab); 494 XDELETEVEC (scnbuf); 495 496 return NULL; 497 } 498 499 /* Fetch the attributes for an simple_object_read. */ 500 501 static void * 502 simple_object_xcoff_fetch_attributes (simple_object_read *sobj, 503 const char **errmsg ATTRIBUTE_UNUSED, 504 int *err ATTRIBUTE_UNUSED) 505 { 506 struct simple_object_xcoff_read *ocr = 507 (struct simple_object_xcoff_read *) sobj->data; 508 struct simple_object_xcoff_attributes *ret; 509 510 ret = XNEW (struct simple_object_xcoff_attributes); 511 ret->magic = ocr->magic; 512 ret->flags = ocr->flags; 513 return ret; 514 } 515 516 /* Release the private data for an simple_object_read. */ 517 518 static void 519 simple_object_xcoff_release_read (void *data) 520 { 521 XDELETE (data); 522 } 523 524 /* Compare two attributes structures. */ 525 526 static const char * 527 simple_object_xcoff_attributes_merge (void *todata, void *fromdata, int *err) 528 { 529 struct simple_object_xcoff_attributes *to = 530 (struct simple_object_xcoff_attributes *) todata; 531 struct simple_object_xcoff_attributes *from = 532 (struct simple_object_xcoff_attributes *) fromdata; 533 534 if (to->magic != from->magic) 535 { 536 *err = 0; 537 return "XCOFF object format mismatch"; 538 } 539 return NULL; 540 } 541 542 /* Release the private data for an attributes structure. */ 543 544 static void 545 simple_object_xcoff_release_attributes (void *data) 546 { 547 XDELETE (data); 548 } 549 550 /* Prepare to write out a file. */ 551 552 static void * 553 simple_object_xcoff_start_write (void *attributes_data, 554 const char **errmsg ATTRIBUTE_UNUSED, 555 int *err ATTRIBUTE_UNUSED) 556 { 557 struct simple_object_xcoff_attributes *attrs = 558 (struct simple_object_xcoff_attributes *) attributes_data; 559 struct simple_object_xcoff_attributes *ret; 560 561 /* We're just going to record the attributes, but we need to make a 562 copy because the user may delete them. */ 563 ret = XNEW (struct simple_object_xcoff_attributes); 564 *ret = *attrs; 565 return ret; 566 } 567 568 /* Write out a XCOFF filehdr. */ 569 570 static int 571 simple_object_xcoff_write_filehdr (simple_object_write *sobj, int descriptor, 572 unsigned int nscns, size_t symtab_offset, 573 unsigned int nsyms, const char **errmsg, 574 int *err) 575 { 576 struct simple_object_xcoff_attributes *attrs = 577 (struct simple_object_xcoff_attributes *) sobj->data; 578 int u64 = attrs->magic == U64_TOCMAGIC; 579 unsigned char hdrbuf[sizeof (struct external_filehdr)]; 580 unsigned char *hdr; 581 void (*set_16) (unsigned char *, unsigned short); 582 void (*set_32) (unsigned char *, unsigned int); 583 void (*set_64) (unsigned char *, ulong_type); 584 585 hdr = &hdrbuf[0]; 586 587 set_16 = simple_object_set_big_16; 588 set_32 = simple_object_set_big_32; 589 set_64 = simple_object_set_big_64; 590 591 memset (hdr, 0, sizeof (struct external_filehdr)); 592 593 set_16 (hdr + offsetof (struct external_filehdr, f_magic), attrs->magic); 594 set_16 (hdr + offsetof (struct external_filehdr, f_nscns), nscns); 595 /* f_timdat left as zero. */ 596 if (u64) 597 { 598 set_64 (hdr + offsetof (struct external_filehdr, u.xcoff64.f_symptr), 599 symtab_offset); 600 set_32 (hdr + offsetof (struct external_filehdr, u.xcoff64.f_nsyms), 601 nsyms); 602 /* f_opthdr left as zero. */ 603 set_16 (hdr + offsetof (struct external_filehdr, u.xcoff64.f_flags), 604 attrs->flags); 605 } 606 else 607 { 608 set_32 (hdr + offsetof (struct external_filehdr, u.xcoff64.f_symptr), 609 symtab_offset); 610 set_32 (hdr + offsetof (struct external_filehdr, u.xcoff64.f_nsyms), 611 nsyms); 612 /* f_opthdr left as zero. */ 613 set_16 (hdr + offsetof (struct external_filehdr, u.xcoff64.f_flags), 614 attrs->flags); 615 } 616 617 return simple_object_internal_write (descriptor, 0, hdrbuf, 618 sizeof (struct external_filehdr), 619 errmsg, err); 620 } 621 622 /* Write out a XCOFF section header. */ 623 624 static int 625 simple_object_xcoff_write_scnhdr (simple_object_write *sobj, 626 int descriptor, 627 const char *name, size_t *name_offset, 628 off_t scnhdr_offset, size_t scnsize, 629 off_t offset, unsigned int align, 630 const char **errmsg, int *err) 631 { 632 struct simple_object_xcoff_read *ocr = 633 (struct simple_object_xcoff_read *) sobj->data; 634 int u64 = ocr->magic == U64_TOCMAGIC; 635 void (*set_32) (unsigned char *, unsigned int); 636 void (*set_64) (unsigned char *, unsigned int); 637 unsigned char hdrbuf[sizeof (struct external_scnhdr)]; 638 unsigned char *hdr; 639 size_t namelen; 640 unsigned int flags; 641 642 set_32 = simple_object_set_big_32; 643 set_64 = simple_object_set_big_32; 644 645 memset (hdrbuf, 0, sizeof hdrbuf); 646 hdr = &hdrbuf[0]; 647 648 namelen = strlen (name); 649 if (namelen <= SCNNMLEN) 650 strncpy ((char *) hdr + offsetof (struct external_scnhdr, s_name), 651 name, SCNNMLEN); 652 else 653 { 654 snprintf ((char *) hdr + offsetof (struct external_scnhdr, s_name), 655 SCNNMLEN, "/%lu", (unsigned long) *name_offset); 656 *name_offset += namelen + 1; 657 } 658 659 /* s_paddr left as zero. */ 660 /* s_vaddr left as zero. */ 661 if (u64) 662 { 663 set_64 (hdr + offsetof (struct external_scnhdr, u.xcoff64.s_size), 664 scnsize); 665 set_64 (hdr + offsetof (struct external_scnhdr, u.xcoff64.s_scnptr), 666 offset); 667 } 668 else 669 { 670 set_32 (hdr + offsetof (struct external_scnhdr, u.xcoff32.s_size), 671 scnsize); 672 set_32 (hdr + offsetof (struct external_scnhdr, u.xcoff32.s_scnptr), 673 offset); 674 } 675 /* s_relptr left as zero. */ 676 /* s_lnnoptr left as zero. */ 677 /* s_nreloc left as zero. */ 678 /* s_nlnno left as zero. */ 679 flags = STYP_DATA; 680 if (align > 13) 681 align = 13; 682 if (u64) 683 set_32 (hdr + offsetof (struct external_scnhdr, u.xcoff64.s_flags), flags); 684 else 685 set_32 (hdr + offsetof (struct external_scnhdr, u.xcoff32.s_flags), flags); 686 687 return simple_object_internal_write (descriptor, scnhdr_offset, hdrbuf, 688 u64 ? SCNHSZ64 : SCNHSZ32, 689 errmsg, err); 690 } 691 692 /* Write out a complete XCOFF file. */ 693 694 static const char * 695 simple_object_xcoff_write_to_file (simple_object_write *sobj, int descriptor, 696 int *err) 697 { 698 struct simple_object_xcoff_read *ocr = 699 (struct simple_object_xcoff_read *) sobj->data; 700 int u64 = ocr->magic == U64_TOCMAGIC; 701 unsigned int nscns, secnum; 702 simple_object_write_section *section; 703 off_t scnhdr_offset; 704 size_t symtab_offset; 705 off_t secsym_offset; 706 unsigned int nsyms; 707 size_t offset; 708 size_t name_offset; 709 const char *errmsg; 710 unsigned char strsizebuf[4]; 711 /* The interface doesn't give us access to the name of the input file 712 yet. We want to use its basename for the FILE symbol. This is 713 what 'gas' uses when told to assemble from stdin. */ 714 const char *source_filename = "fake"; 715 size_t sflen; 716 union 717 { 718 struct external_syment sym; 719 union external_auxent aux; 720 } syms[2]; 721 void (*set_16) (unsigned char *, unsigned short); 722 void (*set_32) (unsigned char *, unsigned int); 723 724 set_16 = simple_object_set_big_16; 725 set_32 = simple_object_set_big_32; 726 727 nscns = 0; 728 for (section = sobj->sections; section != NULL; section = section->next) 729 ++nscns; 730 731 scnhdr_offset = sizeof (struct external_filehdr) - (u64 ? 4 : 0); 732 offset = scnhdr_offset + nscns * (u64 ? SCNHSZ64 : SCNHSZ32); 733 name_offset = 4; 734 for (section = sobj->sections; section != NULL; section = section->next) 735 { 736 size_t mask; 737 size_t new_offset; 738 size_t scnsize; 739 struct simple_object_write_section_buffer *buffer; 740 741 mask = (1U << section->align) - 1; 742 new_offset = offset & mask; 743 new_offset &= ~ mask; 744 while (new_offset > offset) 745 { 746 unsigned char zeroes[16]; 747 size_t write; 748 749 memset (zeroes, 0, sizeof zeroes); 750 write = new_offset - offset; 751 if (write > sizeof zeroes) 752 write = sizeof zeroes; 753 if (!simple_object_internal_write (descriptor, offset, zeroes, write, 754 &errmsg, err)) 755 return errmsg; 756 } 757 758 scnsize = 0; 759 for (buffer = section->buffers; buffer != NULL; buffer = buffer->next) 760 { 761 if (!simple_object_internal_write (descriptor, offset + scnsize, 762 ((const unsigned char *) 763 buffer->buffer), 764 buffer->size, &errmsg, err)) 765 return errmsg; 766 scnsize += buffer->size; 767 } 768 769 if (!simple_object_xcoff_write_scnhdr (sobj, descriptor, section->name, 770 &name_offset, scnhdr_offset, 771 scnsize, offset, section->align, 772 &errmsg, err)) 773 return errmsg; 774 775 scnhdr_offset += u64 ? SCNHSZ64 : SCNHSZ32; 776 offset += scnsize; 777 } 778 779 /* Symbol table is always half-word aligned. */ 780 offset += (offset & 1); 781 /* There is a file symbol and a section symbol per section, 782 and each of these has a single auxiliary symbol following. */ 783 nsyms = 2 * (nscns + 1); 784 symtab_offset = offset; 785 /* Advance across space reserved for symbol table to locate 786 start of string table. */ 787 offset += nsyms * SYMESZ; 788 789 /* Write out file symbol. */ 790 memset (&syms[0], 0, sizeof (syms)); 791 if (!u64) 792 strcpy ((char *)&syms[0].sym.u.xcoff32.n.n_name[0], ".file"); 793 set_16 (&syms[0].sym.n_scnum[0], N_DEBUG); 794 set_16 (&syms[0].sym.n_type[0], IMAGE_SYM_TYPE); 795 syms[0].sym.n_sclass[0] = C_FILE; 796 syms[0].sym.n_numaux[0] = 1; 797 /* The name need not be nul-terminated if it fits into the x_fname field 798 directly, but must be if it has to be placed into the string table. */ 799 sflen = strlen (source_filename); 800 if (sflen <= FILNMLEN) 801 memcpy (&syms[1].aux.x_file.x_fname[0], source_filename, sflen); 802 else 803 { 804 set_32 (&syms[1].aux.x_file._x.x_offset[0], name_offset); 805 if (!simple_object_internal_write (descriptor, offset + name_offset, 806 ((const unsigned char *) 807 source_filename), 808 sflen + 1, &errmsg, err)) 809 return errmsg; 810 name_offset += strlen (source_filename) + 1; 811 } 812 if (!simple_object_internal_write (descriptor, symtab_offset, 813 (const unsigned char *) &syms[0], 814 sizeof (syms), &errmsg, err)) 815 return errmsg; 816 817 /* Write the string table length, followed by the strings and section 818 symbols in step with each other. */ 819 set_32 (strsizebuf, name_offset); 820 if (!simple_object_internal_write (descriptor, offset, strsizebuf, 4, 821 &errmsg, err)) 822 return errmsg; 823 824 name_offset = 4; 825 secsym_offset = symtab_offset + sizeof (syms); 826 memset (&syms[0], 0, sizeof (syms)); 827 set_16 (&syms[0].sym.n_type[0], IMAGE_SYM_TYPE); 828 syms[0].sym.n_sclass[0] = C_STAT; 829 syms[0].sym.n_numaux[0] = 1; 830 secnum = 1; 831 832 for (section = sobj->sections; section != NULL; section = section->next) 833 { 834 size_t namelen; 835 size_t scnsize; 836 struct simple_object_write_section_buffer *buffer; 837 838 namelen = strlen (section->name); 839 set_16 (&syms[0].sym.n_scnum[0], secnum++); 840 scnsize = 0; 841 for (buffer = section->buffers; buffer != NULL; buffer = buffer->next) 842 scnsize += buffer->size; 843 set_32 (&syms[1].aux.x_scn.x_scnlen[0], scnsize); 844 if (namelen > SCNNMLEN) 845 { 846 set_32 (&syms[0].sym.u.xcoff32.n.n.n_zeroes[0], 0); 847 set_32 (&syms[0].sym.u.xcoff32.n.n.n_offset[0], name_offset); 848 if (!simple_object_internal_write (descriptor, offset + name_offset, 849 ((const unsigned char *) 850 section->name), 851 namelen + 1, &errmsg, err)) 852 return errmsg; 853 name_offset += namelen + 1; 854 } 855 else 856 { 857 memcpy (&syms[0].sym.u.xcoff32.n.n_name[0], section->name, 858 strlen (section->name)); 859 memset (&syms[0].sym.u.xcoff32.n.n_name[strlen (section->name)], 0, 860 N_SYMNMLEN - strlen (section->name)); 861 } 862 863 if (!simple_object_internal_write (descriptor, secsym_offset, 864 (const unsigned char *) &syms[0], 865 sizeof (syms), &errmsg, err)) 866 return errmsg; 867 secsym_offset += sizeof (syms); 868 } 869 870 if (!simple_object_xcoff_write_filehdr (sobj, descriptor, nscns, 871 symtab_offset, nsyms, &errmsg, err)) 872 return errmsg; 873 874 return NULL; 875 } 876 877 /* Release the private data for an simple_object_write structure. */ 878 879 static void 880 simple_object_xcoff_release_write (void *data) 881 { 882 XDELETE (data); 883 } 884 885 /* The XCOFF functions. */ 886 887 const struct simple_object_functions simple_object_xcoff_functions = 888 { 889 simple_object_xcoff_match, 890 simple_object_xcoff_find_sections, 891 simple_object_xcoff_fetch_attributes, 892 simple_object_xcoff_release_read, 893 simple_object_xcoff_attributes_merge, 894 simple_object_xcoff_release_attributes, 895 simple_object_xcoff_start_write, 896 simple_object_xcoff_write_to_file, 897 simple_object_xcoff_release_write 898 }; 899
