| 1 | /* simple-object-coff.c -- routines to manipulate COFF object files. |
| 2 | Copyright (C) 2010-2019 Free Software Foundation, Inc. |
| 3 | Written by Ian Lance Taylor, Google. |
| 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 | /* COFF structures and constants. */ |
| 46 | |
| 47 | /* COFF 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 | unsigned char f_symptr[4]; /* file pointer to symtab */ |
| 55 | unsigned char f_nsyms[4]; /* number of symtab entries */ |
| 56 | unsigned char f_opthdr[2]; /* sizeof(optional hdr) */ |
| 57 | unsigned char f_flags[2]; /* flags */ |
| 58 | }; |
| 59 | |
| 60 | /* Bits for filehdr f_flags field. */ |
| 61 | |
| 62 | #define F_EXEC (0x0002) |
| 63 | #define IMAGE_FILE_SYSTEM (0x1000) |
| 64 | #define IMAGE_FILE_DLL (0x2000) |
| 65 | |
| 66 | /* COFF section header. */ |
| 67 | |
| 68 | struct external_scnhdr |
| 69 | { |
| 70 | unsigned char s_name[8]; /* section name */ |
| 71 | unsigned char s_paddr[4]; /* physical address, aliased s_nlib */ |
| 72 | unsigned char s_vaddr[4]; /* virtual address */ |
| 73 | unsigned char s_size[4]; /* section size */ |
| 74 | unsigned char s_scnptr[4]; /* file ptr to raw data for section */ |
| 75 | unsigned char s_relptr[4]; /* file ptr to relocation */ |
| 76 | unsigned char s_lnnoptr[4]; /* file ptr to line numbers */ |
| 77 | unsigned char s_nreloc[2]; /* number of relocation entries */ |
| 78 | unsigned char s_nlnno[2]; /* number of line number entries */ |
| 79 | unsigned char s_flags[4]; /* flags */ |
| 80 | }; |
| 81 | |
| 82 | /* The length of the s_name field in struct external_scnhdr. */ |
| 83 | |
| 84 | #define SCNNMLEN (8) |
| 85 | |
| 86 | /* Bits for scnhdr s_flags field. This includes some bits defined |
| 87 | only for PE. This may need to be moved into coff_magic. */ |
| 88 | |
| 89 | #define STYP_DATA (1 << 6) |
| 90 | #define IMAGE_SCN_MEM_DISCARDABLE (1 << 25) |
| 91 | #define IMAGE_SCN_MEM_SHARED (1 << 28) |
| 92 | #define IMAGE_SCN_MEM_READ (1 << 30) |
| 93 | |
| 94 | #define IMAGE_SCN_ALIGN_POWER_BIT_POS 20 |
| 95 | #define IMAGE_SCN_ALIGN_POWER_CONST(val) \ |
| 96 | (((val) + 1) << IMAGE_SCN_ALIGN_POWER_BIT_POS) |
| 97 | |
| 98 | /* COFF symbol table entry. */ |
| 99 | |
| 100 | #define E_SYMNMLEN 8 /* # characters in a symbol name */ |
| 101 | |
| 102 | struct external_syment |
| 103 | { |
| 104 | union |
| 105 | { |
| 106 | unsigned char e_name[E_SYMNMLEN]; |
| 107 | |
| 108 | struct |
| 109 | { |
| 110 | unsigned char e_zeroes[4]; |
| 111 | unsigned char e_offset[4]; |
| 112 | } e; |
| 113 | } e; |
| 114 | |
| 115 | unsigned char e_value[4]; |
| 116 | unsigned char e_scnum[2]; |
| 117 | unsigned char e_type[2]; |
| 118 | unsigned char e_sclass[1]; |
| 119 | unsigned char e_numaux[1]; |
| 120 | }; |
| 121 | |
| 122 | /* Length allowed for filename in aux sym format 4. */ |
| 123 | |
| 124 | #define E_FILNMLEN 18 |
| 125 | |
| 126 | /* Omits x_sym and other unused variants. */ |
| 127 | |
| 128 | union external_auxent |
| 129 | { |
| 130 | /* Aux sym format 4: file. */ |
| 131 | union |
| 132 | { |
| 133 | char x_fname[E_FILNMLEN]; |
| 134 | struct |
| 135 | { |
| 136 | unsigned char x_zeroes[4]; |
| 137 | unsigned char x_offset[4]; |
| 138 | } x_n; |
| 139 | } x_file; |
| 140 | /* Aux sym format 5: section. */ |
| 141 | struct |
| 142 | { |
| 143 | unsigned char x_scnlen[4]; /* section length */ |
| 144 | unsigned char x_nreloc[2]; /* # relocation entries */ |
| 145 | unsigned char x_nlinno[2]; /* # line numbers */ |
| 146 | unsigned char x_checksum[4]; /* section COMDAT checksum */ |
| 147 | unsigned char x_associated[2]; /* COMDAT assoc section index */ |
| 148 | unsigned char x_comdat[1]; /* COMDAT selection number */ |
| 149 | } x_scn; |
| 150 | }; |
| 151 | |
| 152 | /* Symbol-related constants. */ |
| 153 | |
| 154 | #define IMAGE_SYM_DEBUG (-2) |
| 155 | #define IMAGE_SYM_TYPE_NULL (0) |
| 156 | #define IMAGE_SYM_DTYPE_NULL (0) |
| 157 | #define IMAGE_SYM_CLASS_STATIC (3) |
| 158 | #define IMAGE_SYM_CLASS_FILE (103) |
| 159 | |
| 160 | #define IMAGE_SYM_TYPE \ |
| 161 | ((IMAGE_SYM_DTYPE_NULL << 4) | IMAGE_SYM_TYPE_NULL) |
| 162 | |
| 163 | /* Private data for an simple_object_read. */ |
| 164 | |
| 165 | struct simple_object_coff_read |
| 166 | { |
| 167 | /* Magic number. */ |
| 168 | unsigned short magic; |
| 169 | /* Whether the file is big-endian. */ |
| 170 | unsigned char is_big_endian; |
| 171 | /* Number of sections. */ |
| 172 | unsigned short nscns; |
| 173 | /* File offset of symbol table. */ |
| 174 | off_t symptr; |
| 175 | /* Number of symbol table entries. */ |
| 176 | unsigned int nsyms; |
| 177 | /* Flags. */ |
| 178 | unsigned short flags; |
| 179 | /* Offset of section headers in file. */ |
| 180 | off_t scnhdr_offset; |
| 181 | }; |
| 182 | |
| 183 | /* Private data for an simple_object_attributes. */ |
| 184 | |
| 185 | struct simple_object_coff_attributes |
| 186 | { |
| 187 | /* Magic number. */ |
| 188 | unsigned short magic; |
| 189 | /* Whether the file is big-endian. */ |
| 190 | unsigned char is_big_endian; |
| 191 | /* Flags. */ |
| 192 | unsigned short flags; |
| 193 | }; |
| 194 | |
| 195 | /* There is no magic number which indicates a COFF file as opposed to |
| 196 | any other sort of file. Instead, each COFF file starts with a |
| 197 | two-byte magic number which also indicates the type of the target. |
| 198 | This struct holds a magic number as well as characteristics of that |
| 199 | COFF format. */ |
| 200 | |
| 201 | struct coff_magic_struct |
| 202 | { |
| 203 | /* Magic number. */ |
| 204 | unsigned short magic; |
| 205 | /* Whether this magic number is for a big-endian file. */ |
| 206 | unsigned char is_big_endian; |
| 207 | /* Flag bits, in the f_flags fields, which indicates that this file |
| 208 | is not a relocatable object file. There is no flag which |
| 209 | specifically indicates a relocatable object file, it is only |
| 210 | implied by the absence of these flags. */ |
| 211 | unsigned short non_object_flags; |
| 212 | }; |
| 213 | |
| 214 | /* This is a list of the COFF magic numbers which we recognize, namely |
| 215 | the ones used on Windows. More can be added as needed. */ |
| 216 | |
| 217 | static const struct coff_magic_struct coff_magic[] = |
| 218 | { |
| 219 | /* i386. */ |
| 220 | { 0x14c, 0, F_EXEC | IMAGE_FILE_SYSTEM | IMAGE_FILE_DLL }, |
| 221 | /* x86_64. */ |
| 222 | { 0x8664, 0, F_EXEC | IMAGE_FILE_SYSTEM | IMAGE_FILE_DLL } |
| 223 | }; |
| 224 | |
| 225 | /* See if we have a COFF file. */ |
| 226 | |
| 227 | static void * |
| 228 | simple_object_coff_match (unsigned char header[SIMPLE_OBJECT_MATCH_HEADER_LEN], |
| 229 | int descriptor, off_t offset, |
| 230 | const char *segment_name ATTRIBUTE_UNUSED, |
| 231 | const char **errmsg, int *err) |
| 232 | { |
| 233 | size_t c; |
| 234 | unsigned short magic_big; |
| 235 | unsigned short magic_little; |
| 236 | unsigned short magic; |
| 237 | size_t i; |
| 238 | int is_big_endian; |
| 239 | unsigned short (*fetch_16) (const unsigned char *); |
| 240 | unsigned int (*fetch_32) (const unsigned char *); |
| 241 | unsigned char hdrbuf[sizeof (struct external_filehdr)]; |
| 242 | unsigned short flags; |
| 243 | struct simple_object_coff_read *ocr; |
| 244 | |
| 245 | c = sizeof (coff_magic) / sizeof (coff_magic[0]); |
| 246 | magic_big = simple_object_fetch_big_16 (header); |
| 247 | magic_little = simple_object_fetch_little_16 (header); |
| 248 | for (i = 0; i < c; ++i) |
| 249 | { |
| 250 | if (coff_magic[i].is_big_endian |
| 251 | ? coff_magic[i].magic == magic_big |
| 252 | : coff_magic[i].magic == magic_little) |
| 253 | break; |
| 254 | } |
| 255 | if (i >= c) |
| 256 | { |
| 257 | *errmsg = NULL; |
| 258 | *err = 0; |
| 259 | return NULL; |
| 260 | } |
| 261 | is_big_endian = coff_magic[i].is_big_endian; |
| 262 | |
| 263 | magic = is_big_endian ? magic_big : magic_little; |
| 264 | fetch_16 = (is_big_endian |
| 265 | ? simple_object_fetch_big_16 |
| 266 | : simple_object_fetch_little_16); |
| 267 | fetch_32 = (is_big_endian |
| 268 | ? simple_object_fetch_big_32 |
| 269 | : simple_object_fetch_little_32); |
| 270 | |
| 271 | if (!simple_object_internal_read (descriptor, offset, hdrbuf, sizeof hdrbuf, |
| 272 | errmsg, err)) |
| 273 | return NULL; |
| 274 | |
| 275 | flags = fetch_16 (hdrbuf + offsetof (struct external_filehdr, f_flags)); |
| 276 | if ((flags & coff_magic[i].non_object_flags) != 0) |
| 277 | { |
| 278 | *errmsg = "not relocatable object file"; |
| 279 | *err = 0; |
| 280 | return NULL; |
| 281 | } |
| 282 | |
| 283 | ocr = XNEW (struct simple_object_coff_read); |
| 284 | ocr->magic = magic; |
| 285 | ocr->is_big_endian = is_big_endian; |
| 286 | ocr->nscns = fetch_16 (hdrbuf + offsetof (struct external_filehdr, f_nscns)); |
| 287 | ocr->symptr = fetch_32 (hdrbuf |
| 288 | + offsetof (struct external_filehdr, f_symptr)); |
| 289 | ocr->nsyms = fetch_32 (hdrbuf + offsetof (struct external_filehdr, f_nsyms)); |
| 290 | ocr->flags = flags; |
| 291 | ocr->scnhdr_offset = (sizeof (struct external_filehdr) |
| 292 | + fetch_16 (hdrbuf + offsetof (struct external_filehdr, |
| 293 | f_opthdr))); |
| 294 | |
| 295 | return (void *) ocr; |
| 296 | } |
| 297 | |
| 298 | /* Read the string table in a COFF file. */ |
| 299 | |
| 300 | static char * |
| 301 | simple_object_coff_read_strtab (simple_object_read *sobj, size_t *strtab_size, |
| 302 | const char **errmsg, int *err) |
| 303 | { |
| 304 | struct simple_object_coff_read *ocr = |
| 305 | (struct simple_object_coff_read *) sobj->data; |
| 306 | off_t strtab_offset; |
| 307 | unsigned char strsizebuf[4]; |
| 308 | size_t strsize; |
| 309 | char *strtab; |
| 310 | |
| 311 | strtab_offset = sobj->offset + ocr->symptr |
| 312 | + ocr->nsyms * sizeof (struct external_syment); |
| 313 | if (!simple_object_internal_read (sobj->descriptor, strtab_offset, |
| 314 | strsizebuf, 4, errmsg, err)) |
| 315 | return NULL; |
| 316 | strsize = (ocr->is_big_endian |
| 317 | ? simple_object_fetch_big_32 (strsizebuf) |
| 318 | : simple_object_fetch_little_32 (strsizebuf)); |
| 319 | strtab = XNEWVEC (char, strsize); |
| 320 | if (!simple_object_internal_read (sobj->descriptor, strtab_offset, |
| 321 | (unsigned char *) strtab, strsize, errmsg, |
| 322 | err)) |
| 323 | { |
| 324 | XDELETEVEC (strtab); |
| 325 | return NULL; |
| 326 | } |
| 327 | *strtab_size = strsize; |
| 328 | return strtab; |
| 329 | } |
| 330 | |
| 331 | /* Find all sections in a COFF file. */ |
| 332 | |
| 333 | static const char * |
| 334 | simple_object_coff_find_sections (simple_object_read *sobj, |
| 335 | int (*pfn) (void *, const char *, |
| 336 | off_t offset, off_t length), |
| 337 | void *data, |
| 338 | int *err) |
| 339 | { |
| 340 | struct simple_object_coff_read *ocr = |
| 341 | (struct simple_object_coff_read *) sobj->data; |
| 342 | size_t scnhdr_size; |
| 343 | unsigned char *scnbuf; |
| 344 | const char *errmsg; |
| 345 | unsigned int (*fetch_32) (const unsigned char *); |
| 346 | unsigned int nscns; |
| 347 | char *strtab; |
| 348 | size_t strtab_size; |
| 349 | unsigned int i; |
| 350 | |
| 351 | scnhdr_size = sizeof (struct external_scnhdr); |
| 352 | scnbuf = XNEWVEC (unsigned char, scnhdr_size * ocr->nscns); |
| 353 | if (!simple_object_internal_read (sobj->descriptor, |
| 354 | sobj->offset + ocr->scnhdr_offset, |
| 355 | scnbuf, scnhdr_size * ocr->nscns, &errmsg, |
| 356 | err)) |
| 357 | { |
| 358 | XDELETEVEC (scnbuf); |
| 359 | return errmsg; |
| 360 | } |
| 361 | |
| 362 | fetch_32 = (ocr->is_big_endian |
| 363 | ? simple_object_fetch_big_32 |
| 364 | : simple_object_fetch_little_32); |
| 365 | |
| 366 | nscns = ocr->nscns; |
| 367 | strtab = NULL; |
| 368 | strtab_size = 0; |
| 369 | for (i = 0; i < nscns; ++i) |
| 370 | { |
| 371 | unsigned char *scnhdr; |
| 372 | unsigned char *scnname; |
| 373 | char namebuf[SCNNMLEN + 1]; |
| 374 | char *name; |
| 375 | off_t scnptr; |
| 376 | unsigned int size; |
| 377 | |
| 378 | scnhdr = scnbuf + i * scnhdr_size; |
| 379 | scnname = scnhdr + offsetof (struct external_scnhdr, s_name); |
| 380 | memcpy (namebuf, scnname, SCNNMLEN); |
| 381 | namebuf[SCNNMLEN] = '\0'; |
| 382 | name = &namebuf[0]; |
| 383 | if (namebuf[0] == '/') |
| 384 | { |
| 385 | size_t strindex; |
| 386 | char *end; |
| 387 | |
| 388 | strindex = strtol (namebuf + 1, &end, 10); |
| 389 | if (*end == '\0') |
| 390 | { |
| 391 | /* The real section name is found in the string |
| 392 | table. */ |
| 393 | if (strtab == NULL) |
| 394 | { |
| 395 | strtab = simple_object_coff_read_strtab (sobj, |
| 396 | &strtab_size, |
| 397 | &errmsg, err); |
| 398 | if (strtab == NULL) |
| 399 | { |
| 400 | XDELETEVEC (scnbuf); |
| 401 | return errmsg; |
| 402 | } |
| 403 | } |
| 404 | |
| 405 | if (strindex < 4 || strindex >= strtab_size) |
| 406 | { |
| 407 | XDELETEVEC (strtab); |
| 408 | XDELETEVEC (scnbuf); |
| 409 | *err = 0; |
| 410 | return "section string index out of range"; |
| 411 | } |
| 412 | |
| 413 | name = strtab + strindex; |
| 414 | } |
| 415 | } |
| 416 | |
| 417 | scnptr = fetch_32 (scnhdr + offsetof (struct external_scnhdr, s_scnptr)); |
| 418 | size = fetch_32 (scnhdr + offsetof (struct external_scnhdr, s_size)); |
| 419 | |
| 420 | if (!(*pfn) (data, name, scnptr, size)) |
| 421 | break; |
| 422 | } |
| 423 | |
| 424 | if (strtab != NULL) |
| 425 | XDELETEVEC (strtab); |
| 426 | XDELETEVEC (scnbuf); |
| 427 | |
| 428 | return NULL; |
| 429 | } |
| 430 | |
| 431 | /* Fetch the attributes for an simple_object_read. */ |
| 432 | |
| 433 | static void * |
| 434 | simple_object_coff_fetch_attributes (simple_object_read *sobj, |
| 435 | const char **errmsg ATTRIBUTE_UNUSED, |
| 436 | int *err ATTRIBUTE_UNUSED) |
| 437 | { |
| 438 | struct simple_object_coff_read *ocr = |
| 439 | (struct simple_object_coff_read *) sobj->data; |
| 440 | struct simple_object_coff_attributes *ret; |
| 441 | |
| 442 | ret = XNEW (struct simple_object_coff_attributes); |
| 443 | ret->magic = ocr->magic; |
| 444 | ret->is_big_endian = ocr->is_big_endian; |
| 445 | ret->flags = ocr->flags; |
| 446 | return ret; |
| 447 | } |
| 448 | |
| 449 | /* Release the private data for an simple_object_read. */ |
| 450 | |
| 451 | static void |
| 452 | simple_object_coff_release_read (void *data) |
| 453 | { |
| 454 | XDELETE (data); |
| 455 | } |
| 456 | |
| 457 | /* Compare two attributes structures. */ |
| 458 | |
| 459 | static const char * |
| 460 | simple_object_coff_attributes_merge (void *todata, void *fromdata, int *err) |
| 461 | { |
| 462 | struct simple_object_coff_attributes *to = |
| 463 | (struct simple_object_coff_attributes *) todata; |
| 464 | struct simple_object_coff_attributes *from = |
| 465 | (struct simple_object_coff_attributes *) fromdata; |
| 466 | |
| 467 | if (to->magic != from->magic || to->is_big_endian != from->is_big_endian) |
| 468 | { |
| 469 | *err = 0; |
| 470 | return "COFF object format mismatch"; |
| 471 | } |
| 472 | return NULL; |
| 473 | } |
| 474 | |
| 475 | /* Release the private data for an attributes structure. */ |
| 476 | |
| 477 | static void |
| 478 | simple_object_coff_release_attributes (void *data) |
| 479 | { |
| 480 | XDELETE (data); |
| 481 | } |
| 482 | |
| 483 | /* Prepare to write out a file. */ |
| 484 | |
| 485 | static void * |
| 486 | simple_object_coff_start_write (void *attributes_data, |
| 487 | const char **errmsg ATTRIBUTE_UNUSED, |
| 488 | int *err ATTRIBUTE_UNUSED) |
| 489 | { |
| 490 | struct simple_object_coff_attributes *attrs = |
| 491 | (struct simple_object_coff_attributes *) attributes_data; |
| 492 | struct simple_object_coff_attributes *ret; |
| 493 | |
| 494 | /* We're just going to record the attributes, but we need to make a |
| 495 | copy because the user may delete them. */ |
| 496 | ret = XNEW (struct simple_object_coff_attributes); |
| 497 | *ret = *attrs; |
| 498 | return ret; |
| 499 | } |
| 500 | |
| 501 | /* Write out a COFF filehdr. */ |
| 502 | |
| 503 | static int |
| 504 | simple_object_coff_write_filehdr (simple_object_write *sobj, int descriptor, |
| 505 | unsigned int nscns, size_t symtab_offset, |
| 506 | unsigned int nsyms, const char **errmsg, |
| 507 | int *err) |
| 508 | { |
| 509 | struct simple_object_coff_attributes *attrs = |
| 510 | (struct simple_object_coff_attributes *) sobj->data; |
| 511 | unsigned char hdrbuf[sizeof (struct external_filehdr)]; |
| 512 | unsigned char *hdr; |
| 513 | void (*set_16) (unsigned char *, unsigned short); |
| 514 | void (*set_32) (unsigned char *, unsigned int); |
| 515 | |
| 516 | hdr = &hdrbuf[0]; |
| 517 | |
| 518 | set_16 = (attrs->is_big_endian |
| 519 | ? simple_object_set_big_16 |
| 520 | : simple_object_set_little_16); |
| 521 | set_32 = (attrs->is_big_endian |
| 522 | ? simple_object_set_big_32 |
| 523 | : simple_object_set_little_32); |
| 524 | |
| 525 | memset (hdr, 0, sizeof (struct external_filehdr)); |
| 526 | |
| 527 | set_16 (hdr + offsetof (struct external_filehdr, f_magic), attrs->magic); |
| 528 | set_16 (hdr + offsetof (struct external_filehdr, f_nscns), nscns); |
| 529 | /* f_timdat left as zero. */ |
| 530 | set_32 (hdr + offsetof (struct external_filehdr, f_symptr), symtab_offset); |
| 531 | set_32 (hdr + offsetof (struct external_filehdr, f_nsyms), nsyms); |
| 532 | /* f_opthdr left as zero. */ |
| 533 | set_16 (hdr + offsetof (struct external_filehdr, f_flags), attrs->flags); |
| 534 | |
| 535 | return simple_object_internal_write (descriptor, 0, hdrbuf, |
| 536 | sizeof (struct external_filehdr), |
| 537 | errmsg, err); |
| 538 | } |
| 539 | |
| 540 | /* Write out a COFF section header. */ |
| 541 | |
| 542 | static int |
| 543 | simple_object_coff_write_scnhdr (simple_object_write *sobj, int descriptor, |
| 544 | const char *name, size_t *name_offset, |
| 545 | off_t scnhdr_offset, size_t scnsize, |
| 546 | off_t offset, unsigned int align, |
| 547 | const char **errmsg, int *err) |
| 548 | { |
| 549 | struct simple_object_coff_attributes *attrs = |
| 550 | (struct simple_object_coff_attributes *) sobj->data; |
| 551 | void (*set_32) (unsigned char *, unsigned int); |
| 552 | unsigned char hdrbuf[sizeof (struct external_scnhdr)]; |
| 553 | unsigned char *hdr; |
| 554 | size_t namelen; |
| 555 | unsigned int flags; |
| 556 | |
| 557 | set_32 = (attrs->is_big_endian |
| 558 | ? simple_object_set_big_32 |
| 559 | : simple_object_set_little_32); |
| 560 | |
| 561 | memset (hdrbuf, 0, sizeof hdrbuf); |
| 562 | hdr = &hdrbuf[0]; |
| 563 | |
| 564 | namelen = strlen (name); |
| 565 | if (namelen <= SCNNMLEN) |
| 566 | strncpy ((char *) hdr + offsetof (struct external_scnhdr, s_name), name, |
| 567 | SCNNMLEN); |
| 568 | else |
| 569 | { |
| 570 | snprintf ((char *) hdr + offsetof (struct external_scnhdr, s_name), |
| 571 | SCNNMLEN, "/%lu", (unsigned long) *name_offset); |
| 572 | *name_offset += namelen + 1; |
| 573 | } |
| 574 | |
| 575 | /* s_paddr left as zero. */ |
| 576 | /* s_vaddr left as zero. */ |
| 577 | set_32 (hdr + offsetof (struct external_scnhdr, s_size), scnsize); |
| 578 | set_32 (hdr + offsetof (struct external_scnhdr, s_scnptr), offset); |
| 579 | /* s_relptr left as zero. */ |
| 580 | /* s_lnnoptr left as zero. */ |
| 581 | /* s_nreloc left as zero. */ |
| 582 | /* s_nlnno left as zero. */ |
| 583 | flags = (STYP_DATA | IMAGE_SCN_MEM_DISCARDABLE | IMAGE_SCN_MEM_SHARED |
| 584 | | IMAGE_SCN_MEM_READ); |
| 585 | /* PE can represent alignment up to 13. */ |
| 586 | if (align > 13) |
| 587 | align = 13; |
| 588 | flags |= IMAGE_SCN_ALIGN_POWER_CONST(align); |
| 589 | set_32 (hdr + offsetof (struct external_scnhdr, s_flags), flags); |
| 590 | |
| 591 | return simple_object_internal_write (descriptor, scnhdr_offset, hdrbuf, |
| 592 | sizeof (struct external_scnhdr), |
| 593 | errmsg, err); |
| 594 | } |
| 595 | |
| 596 | /* Write out a complete COFF file. */ |
| 597 | |
| 598 | static const char * |
| 599 | simple_object_coff_write_to_file (simple_object_write *sobj, int descriptor, |
| 600 | int *err) |
| 601 | { |
| 602 | struct simple_object_coff_attributes *attrs = |
| 603 | (struct simple_object_coff_attributes *) sobj->data; |
| 604 | unsigned int nscns, secnum; |
| 605 | simple_object_write_section *section; |
| 606 | off_t scnhdr_offset; |
| 607 | size_t symtab_offset; |
| 608 | off_t secsym_offset; |
| 609 | unsigned int nsyms; |
| 610 | size_t offset; |
| 611 | size_t name_offset; |
| 612 | const char *errmsg; |
| 613 | unsigned char strsizebuf[4]; |
| 614 | /* The interface doesn't give us access to the name of the input file |
| 615 | yet. We want to use its basename for the FILE symbol. This is |
| 616 | what 'gas' uses when told to assemble from stdin. */ |
| 617 | const char *source_filename = "fake"; |
| 618 | size_t sflen; |
| 619 | union |
| 620 | { |
| 621 | struct external_syment sym; |
| 622 | union external_auxent aux; |
| 623 | } syms[2]; |
| 624 | void (*set_16) (unsigned char *, unsigned short); |
| 625 | void (*set_32) (unsigned char *, unsigned int); |
| 626 | |
| 627 | set_16 = (attrs->is_big_endian |
| 628 | ? simple_object_set_big_16 |
| 629 | : simple_object_set_little_16); |
| 630 | set_32 = (attrs->is_big_endian |
| 631 | ? simple_object_set_big_32 |
| 632 | : simple_object_set_little_32); |
| 633 | |
| 634 | nscns = 0; |
| 635 | for (section = sobj->sections; section != NULL; section = section->next) |
| 636 | ++nscns; |
| 637 | |
| 638 | scnhdr_offset = sizeof (struct external_filehdr); |
| 639 | offset = scnhdr_offset + nscns * sizeof (struct external_scnhdr); |
| 640 | name_offset = 4; |
| 641 | for (section = sobj->sections; section != NULL; section = section->next) |
| 642 | { |
| 643 | size_t mask; |
| 644 | size_t new_offset; |
| 645 | size_t scnsize; |
| 646 | struct simple_object_write_section_buffer *buffer; |
| 647 | |
| 648 | mask = (1U << section->align) - 1; |
| 649 | new_offset = offset & mask; |
| 650 | new_offset &= ~ mask; |
| 651 | while (new_offset > offset) |
| 652 | { |
| 653 | unsigned char zeroes[16]; |
| 654 | size_t write; |
| 655 | |
| 656 | memset (zeroes, 0, sizeof zeroes); |
| 657 | write = new_offset - offset; |
| 658 | if (write > sizeof zeroes) |
| 659 | write = sizeof zeroes; |
| 660 | if (!simple_object_internal_write (descriptor, offset, zeroes, write, |
| 661 | &errmsg, err)) |
| 662 | return errmsg; |
| 663 | } |
| 664 | |
| 665 | scnsize = 0; |
| 666 | for (buffer = section->buffers; buffer != NULL; buffer = buffer->next) |
| 667 | { |
| 668 | if (!simple_object_internal_write (descriptor, offset + scnsize, |
| 669 | ((const unsigned char *) |
| 670 | buffer->buffer), |
| 671 | buffer->size, &errmsg, err)) |
| 672 | return errmsg; |
| 673 | scnsize += buffer->size; |
| 674 | } |
| 675 | |
| 676 | if (!simple_object_coff_write_scnhdr (sobj, descriptor, section->name, |
| 677 | &name_offset, scnhdr_offset, |
| 678 | scnsize, offset, section->align, |
| 679 | &errmsg, err)) |
| 680 | return errmsg; |
| 681 | |
| 682 | scnhdr_offset += sizeof (struct external_scnhdr); |
| 683 | offset += scnsize; |
| 684 | } |
| 685 | |
| 686 | /* Symbol table is always half-word aligned. */ |
| 687 | offset += (offset & 1); |
| 688 | /* There is a file symbol and a section symbol per section, |
| 689 | and each of these has a single auxiliary symbol following. */ |
| 690 | nsyms = 2 * (nscns + 1); |
| 691 | symtab_offset = offset; |
| 692 | /* Advance across space reserved for symbol table to locate |
| 693 | start of string table. */ |
| 694 | offset += nsyms * sizeof (struct external_syment); |
| 695 | |
| 696 | /* Write out file symbol. */ |
| 697 | memset (&syms[0], 0, sizeof (syms)); |
| 698 | strcpy ((char *)&syms[0].sym.e.e_name[0], ".file"); |
| 699 | set_16 (&syms[0].sym.e_scnum[0], IMAGE_SYM_DEBUG); |
| 700 | set_16 (&syms[0].sym.e_type[0], IMAGE_SYM_TYPE); |
| 701 | syms[0].sym.e_sclass[0] = IMAGE_SYM_CLASS_FILE; |
| 702 | syms[0].sym.e_numaux[0] = 1; |
| 703 | /* The name need not be nul-terminated if it fits into the x_fname field |
| 704 | directly, but must be if it has to be placed into the string table. */ |
| 705 | sflen = strlen (source_filename); |
| 706 | if (sflen <= E_FILNMLEN) |
| 707 | memcpy (&syms[1].aux.x_file.x_fname[0], source_filename, sflen); |
| 708 | else |
| 709 | { |
| 710 | set_32 (&syms[1].aux.x_file.x_n.x_offset[0], name_offset); |
| 711 | if (!simple_object_internal_write (descriptor, offset + name_offset, |
| 712 | ((const unsigned char *) |
| 713 | source_filename), |
| 714 | sflen + 1, &errmsg, err)) |
| 715 | return errmsg; |
| 716 | name_offset += strlen (source_filename) + 1; |
| 717 | } |
| 718 | if (!simple_object_internal_write (descriptor, symtab_offset, |
| 719 | (const unsigned char *) &syms[0], |
| 720 | sizeof (syms), &errmsg, err)) |
| 721 | return errmsg; |
| 722 | |
| 723 | /* Write the string table length, followed by the strings and section |
| 724 | symbols in step with each other. */ |
| 725 | set_32 (strsizebuf, name_offset); |
| 726 | if (!simple_object_internal_write (descriptor, offset, strsizebuf, 4, |
| 727 | &errmsg, err)) |
| 728 | return errmsg; |
| 729 | |
| 730 | name_offset = 4; |
| 731 | secsym_offset = symtab_offset + sizeof (syms); |
| 732 | memset (&syms[0], 0, sizeof (syms)); |
| 733 | set_16 (&syms[0].sym.e_type[0], IMAGE_SYM_TYPE); |
| 734 | syms[0].sym.e_sclass[0] = IMAGE_SYM_CLASS_STATIC; |
| 735 | syms[0].sym.e_numaux[0] = 1; |
| 736 | secnum = 1; |
| 737 | |
| 738 | for (section = sobj->sections; section != NULL; section = section->next) |
| 739 | { |
| 740 | size_t namelen; |
| 741 | size_t scnsize; |
| 742 | struct simple_object_write_section_buffer *buffer; |
| 743 | |
| 744 | namelen = strlen (section->name); |
| 745 | set_16 (&syms[0].sym.e_scnum[0], secnum++); |
| 746 | scnsize = 0; |
| 747 | for (buffer = section->buffers; buffer != NULL; buffer = buffer->next) |
| 748 | scnsize += buffer->size; |
| 749 | set_32 (&syms[1].aux.x_scn.x_scnlen[0], scnsize); |
| 750 | if (namelen > SCNNMLEN) |
| 751 | { |
| 752 | set_32 (&syms[0].sym.e.e.e_zeroes[0], 0); |
| 753 | set_32 (&syms[0].sym.e.e.e_offset[0], name_offset); |
| 754 | if (!simple_object_internal_write (descriptor, offset + name_offset, |
| 755 | ((const unsigned char *) |
| 756 | section->name), |
| 757 | namelen + 1, &errmsg, err)) |
| 758 | return errmsg; |
| 759 | name_offset += namelen + 1; |
| 760 | } |
| 761 | else |
| 762 | { |
| 763 | memcpy (&syms[0].sym.e.e_name[0], section->name, |
| 764 | strlen (section->name)); |
| 765 | memset (&syms[0].sym.e.e_name[strlen (section->name)], 0, |
| 766 | E_SYMNMLEN - strlen (section->name)); |
| 767 | } |
| 768 | |
| 769 | if (!simple_object_internal_write (descriptor, secsym_offset, |
| 770 | (const unsigned char *) &syms[0], |
| 771 | sizeof (syms), &errmsg, err)) |
| 772 | return errmsg; |
| 773 | secsym_offset += sizeof (syms); |
| 774 | } |
| 775 | |
| 776 | if (!simple_object_coff_write_filehdr (sobj, descriptor, nscns, |
| 777 | symtab_offset, nsyms, &errmsg, err)) |
| 778 | return errmsg; |
| 779 | |
| 780 | return NULL; |
| 781 | } |
| 782 | |
| 783 | /* Release the private data for an simple_object_write structure. */ |
| 784 | |
| 785 | static void |
| 786 | simple_object_coff_release_write (void *data) |
| 787 | { |
| 788 | XDELETE (data); |
| 789 | } |
| 790 | |
| 791 | /* The COFF functions. */ |
| 792 | |
| 793 | const struct simple_object_functions simple_object_coff_functions = |
| 794 | { |
| 795 | simple_object_coff_match, |
| 796 | simple_object_coff_find_sections, |
| 797 | simple_object_coff_fetch_attributes, |
| 798 | simple_object_coff_release_read, |
| 799 | simple_object_coff_attributes_merge, |
| 800 | simple_object_coff_release_attributes, |
| 801 | simple_object_coff_start_write, |
| 802 | simple_object_coff_write_to_file, |
| 803 | simple_object_coff_release_write, |
| 804 | NULL |
| 805 | }; |