| 1 | /* Object file "section" support for the BFD library. |
| 2 | Copyright (C) 1990, 1991, 1992, 1993 Free Software Foundation, Inc. |
| 3 | Written by Cygnus Support. |
| 4 | |
| 5 | This file is part of BFD, the Binary File Descriptor library. |
| 6 | |
| 7 | This program 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 2 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program 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 this program; if not, write to the Free Software |
| 19 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| 20 | |
| 21 | /* |
| 22 | SECTION |
| 23 | Sections |
| 24 | |
| 25 | Sections are supported in BFD in <<section.c>>. |
| 26 | |
| 27 | The raw data contained within a BFD is maintained through the |
| 28 | section abstraction. A single BFD may have any number of |
| 29 | sections, and keeps hold of them by pointing to the first, |
| 30 | each one points to the next in the list. |
| 31 | |
| 32 | @menu |
| 33 | @* Section Input:: |
| 34 | @* Section Output:: |
| 35 | @* typedef asection:: |
| 36 | @* section prototypes:: |
| 37 | @end menu |
| 38 | |
| 39 | INODE |
| 40 | Section Input, Section Output, Sections, Sections |
| 41 | SUBSECTION |
| 42 | Section Input |
| 43 | |
| 44 | When a BFD is opened for reading, the section structures are |
| 45 | created and attached to the BFD. |
| 46 | |
| 47 | Each section has a name which describes the section in the |
| 48 | outside world - for example, <<a.out>> would contain at least |
| 49 | three sections, called <<.text>>, <<.data>> and <<.bss>>. |
| 50 | |
| 51 | Sometimes a BFD will contain more than the 'natural' number of |
| 52 | sections. A back end may attach other sections containing |
| 53 | constructor data, or an application may add a section (using |
| 54 | bfd_make_section) to the sections attached to an already open |
| 55 | BFD. For example, the linker creates a supernumary section |
| 56 | <<COMMON>> for each input file's BFD to hold information about |
| 57 | common storage. |
| 58 | |
| 59 | The raw data is not necessarily read in at the same time as |
| 60 | the section descriptor is created. Some targets may leave the |
| 61 | data in place until a <<bfd_get_section_contents>> call is |
| 62 | made. Other back ends may read in all the data at once - For |
| 63 | example; an S-record file has to be read once to determine the |
| 64 | size of the data. An IEEE-695 file doesn't contain raw data in |
| 65 | sections, but data and relocation expressions intermixed, so |
| 66 | the data area has to be parsed to get out the data and |
| 67 | relocations. |
| 68 | |
| 69 | INODE |
| 70 | Section Output, typedef asection, Section Input, Sections |
| 71 | |
| 72 | SUBSECTION |
| 73 | Section Output |
| 74 | |
| 75 | To write a new object style BFD, the various sections to be |
| 76 | written have to be created. They are attached to the BFD in |
| 77 | the same way as input sections, data is written to the |
| 78 | sections using <<bfd_set_section_contents>>. |
| 79 | |
| 80 | Any program that creates or combines sections (e.g., the assembler |
| 81 | and linker) must use the fields <<output_section>> and |
| 82 | <<output_offset>> to indicate the file sections to which each |
| 83 | section must be written. (If the section is being created from |
| 84 | scratch, <<output_section>> should probably point to the section |
| 85 | itself, and <<output_offset>> should probably be zero.) |
| 86 | |
| 87 | The data to be written comes from input sections attached to |
| 88 | the output sections. The output section structure can be |
| 89 | considered a filter for the input section, the output section |
| 90 | determines the vma of the output data and the name, but the |
| 91 | input section determines the offset into the output section of |
| 92 | the data to be written. |
| 93 | |
| 94 | E.g., to create a section "O", starting at 0x100, 0x123 long, |
| 95 | containing two subsections, "A" at offset 0x0 (ie at vma |
| 96 | 0x100) and "B" at offset 0x20 (ie at vma 0x120) the structures |
| 97 | would look like: |
| 98 | |
| 99 | | section name "A" |
| 100 | | output_offset 0x00 |
| 101 | | size 0x20 |
| 102 | | output_section -----------> section name "O" |
| 103 | | | vma 0x100 |
| 104 | | section name "B" | size 0x123 |
| 105 | | output_offset 0x20 | |
| 106 | | size 0x103 | |
| 107 | | output_section --------| |
| 108 | |
| 109 | |
| 110 | SUBSECTION |
| 111 | Seglets |
| 112 | |
| 113 | The data within a section is stored in a <<seglet>>. These |
| 114 | are much like the fixups in <<gas>>. The seglet abstraction |
| 115 | allows the a section to grow and shrink within itself. |
| 116 | |
| 117 | A seglet knows how big it is, and which is the next seglet and |
| 118 | where the raw data for it is, and also points to a list of |
| 119 | relocations which apply to it. |
| 120 | |
| 121 | The seglet is used by the linker to perform relaxing on final |
| 122 | code. The application creates code which is as big as |
| 123 | necessary to make it work without relaxing, and the user can |
| 124 | select whether to relax. Sometimes relaxing takes a lot of |
| 125 | time. The linker runs around the relocations to see if any |
| 126 | are attached to data which can be shrunk, if so it does it on |
| 127 | a seglet by seglet basis. |
| 128 | |
| 129 | */ |
| 130 | |
| 131 | |
| 132 | #include "bfd.h" |
| 133 | #include "sysdep.h" |
| 134 | #include "libbfd.h" |
| 135 | |
| 136 | |
| 137 | /* |
| 138 | DOCDD |
| 139 | INODE |
| 140 | typedef asection, section prototypes, Section Output, Sections |
| 141 | SUBSECTION |
| 142 | typedef asection |
| 143 | |
| 144 | The shape of a section struct: |
| 145 | |
| 146 | CODE_FRAGMENT |
| 147 | . |
| 148 | .typedef struct sec |
| 149 | .{ |
| 150 | . {* The name of the section, the name isn't a copy, the pointer is |
| 151 | . the same as that passed to bfd_make_section. *} |
| 152 | . |
| 153 | . CONST char *name; |
| 154 | . |
| 155 | . |
| 156 | . {* Which section is it 0.nth *} |
| 157 | . |
| 158 | . int index; |
| 159 | . |
| 160 | . {* The next section in the list belonging to the BFD, or NULL. *} |
| 161 | . |
| 162 | . struct sec *next; |
| 163 | . |
| 164 | . {* The field flags contains attributes of the section. Some of |
| 165 | . flags are read in from the object file, and some are |
| 166 | . synthesized from other information. *} |
| 167 | . |
| 168 | . flagword flags; |
| 169 | . |
| 170 | .#define SEC_NO_FLAGS 0x000 |
| 171 | . |
| 172 | . {* Tells the OS to allocate space for this section when loaded. |
| 173 | . This would clear for a section containing debug information |
| 174 | . only. *} |
| 175 | . |
| 176 | . |
| 177 | .#define SEC_ALLOC 0x001 |
| 178 | . {* Tells the OS to load the section from the file when loading. |
| 179 | . This would be clear for a .bss section *} |
| 180 | . |
| 181 | .#define SEC_LOAD 0x002 |
| 182 | . {* The section contains data still to be relocated, so there will |
| 183 | . be some relocation information too. *} |
| 184 | . |
| 185 | .#define SEC_RELOC 0x004 |
| 186 | . |
| 187 | . {* Obsolete ? *} |
| 188 | . |
| 189 | .#define SEC_BALIGN 0x008 |
| 190 | . |
| 191 | . {* A signal to the OS that the section contains read only |
| 192 | . data. *} |
| 193 | .#define SEC_READONLY 0x010 |
| 194 | . |
| 195 | . {* The section contains code only. *} |
| 196 | . |
| 197 | .#define SEC_CODE 0x020 |
| 198 | . |
| 199 | . {* The section contains data only. *} |
| 200 | . |
| 201 | .#define SEC_DATA 0x040 |
| 202 | . |
| 203 | . {* The section will reside in ROM. *} |
| 204 | . |
| 205 | .#define SEC_ROM 0x080 |
| 206 | . |
| 207 | . {* The section contains constructor information. This section |
| 208 | . type is used by the linker to create lists of constructors and |
| 209 | . destructors used by <<g++>>. When a back end sees a symbol |
| 210 | . which should be used in a constructor list, it creates a new |
| 211 | . section for the type of name (eg <<__CTOR_LIST__>>), attaches |
| 212 | . the symbol to it and builds a relocation. To build the lists |
| 213 | . of constructors, all the linker has to to is catenate all the |
| 214 | . sections called <<__CTOR_LIST__>> and relocte the data |
| 215 | . contained within - exactly the operations it would peform on |
| 216 | . standard data. *} |
| 217 | . |
| 218 | .#define SEC_CONSTRUCTOR 0x100 |
| 219 | . |
| 220 | . {* The section is a constuctor, and should be placed at the |
| 221 | . end of the . *} |
| 222 | . |
| 223 | .#define SEC_CONSTRUCTOR_TEXT 0x1100 |
| 224 | . |
| 225 | .#define SEC_CONSTRUCTOR_DATA 0x2100 |
| 226 | . |
| 227 | .#define SEC_CONSTRUCTOR_BSS 0x3100 |
| 228 | . |
| 229 | . {* The section has contents - a data section could be |
| 230 | . <<SEC_ALLOC>> | <<SEC_HAS_CONTENTS>>, a debug section could be |
| 231 | . <<SEC_HAS_CONTENTS>> *} |
| 232 | . |
| 233 | .#define SEC_HAS_CONTENTS 0x200 |
| 234 | . |
| 235 | . {* An instruction to the linker not to output sections |
| 236 | . containing this flag even if they have information which |
| 237 | . would normally be written. *} |
| 238 | . |
| 239 | .#define SEC_NEVER_LOAD 0x400 |
| 240 | . |
| 241 | . {* The section is a shared library section. The linker must leave |
| 242 | . these completely alone, as the vma and size are used when |
| 243 | . the executable is loaded. *} |
| 244 | . |
| 245 | .#define SEC_SHARED_LIBRARY 0x800 |
| 246 | . |
| 247 | . {* The section is a common section (symbols may be defined |
| 248 | . multiple times, the value of a symbol is the amount of |
| 249 | . space it requires, and the largest symbol value is the one |
| 250 | . used). Most targets have exactly one of these (.bss), but |
| 251 | . ECOFF has two. *} |
| 252 | . |
| 253 | .#define SEC_IS_COMMON 0x8000 |
| 254 | . |
| 255 | . bfd_vma vma; |
| 256 | . boolean user_set_vma; |
| 257 | . |
| 258 | . {* The size of the section in bytes, as it will be output. |
| 259 | . contains a value even if the section has no contents (eg, the |
| 260 | . size of <<.bss>>). This will be filled in after relocation *} |
| 261 | . |
| 262 | . bfd_size_type _cooked_size; |
| 263 | . |
| 264 | . {* The size on disk of the section in bytes originally. Normally this |
| 265 | . value is the same as the size, but if some relaxing has |
| 266 | . been done, then this value will be bigger. *} |
| 267 | . |
| 268 | . bfd_size_type _raw_size; |
| 269 | . |
| 270 | . {* If this section is going to be output, then this value is the |
| 271 | . offset into the output section of the first byte in the input |
| 272 | . section. Eg, if this was going to start at the 100th byte in |
| 273 | . the output section, this value would be 100. *} |
| 274 | . |
| 275 | . bfd_vma output_offset; |
| 276 | . |
| 277 | . {* The output section through which to map on output. *} |
| 278 | . |
| 279 | . struct sec *output_section; |
| 280 | . |
| 281 | . {* The alignment requirement of the section, as an exponent - eg |
| 282 | . 3 aligns to 2^3 (or 8) *} |
| 283 | . |
| 284 | . unsigned int alignment_power; |
| 285 | . |
| 286 | . {* If an input section, a pointer to a vector of relocation |
| 287 | . records for the data in this section. *} |
| 288 | . |
| 289 | . struct reloc_cache_entry *relocation; |
| 290 | . |
| 291 | . {* If an output section, a pointer to a vector of pointers to |
| 292 | . relocation records for the data in this section. *} |
| 293 | . |
| 294 | . struct reloc_cache_entry **orelocation; |
| 295 | . |
| 296 | . {* The number of relocation records in one of the above *} |
| 297 | . |
| 298 | . unsigned reloc_count; |
| 299 | . |
| 300 | . {* Information below is back end specific - and not always used |
| 301 | . or updated |
| 302 | . |
| 303 | . File position of section data *} |
| 304 | . |
| 305 | . file_ptr filepos; |
| 306 | . |
| 307 | . {* File position of relocation info *} |
| 308 | . |
| 309 | . file_ptr rel_filepos; |
| 310 | . |
| 311 | . {* File position of line data *} |
| 312 | . |
| 313 | . file_ptr line_filepos; |
| 314 | . |
| 315 | . {* Pointer to data for applications *} |
| 316 | . |
| 317 | . PTR userdata; |
| 318 | . |
| 319 | . struct lang_output_section *otheruserdata; |
| 320 | . |
| 321 | . {* Attached line number information *} |
| 322 | . |
| 323 | . alent *lineno; |
| 324 | . |
| 325 | . {* Number of line number records *} |
| 326 | . |
| 327 | . unsigned int lineno_count; |
| 328 | . |
| 329 | . {* When a section is being output, this value changes as more |
| 330 | . linenumbers are written out *} |
| 331 | . |
| 332 | . file_ptr moving_line_filepos; |
| 333 | . |
| 334 | . {* what the section number is in the target world *} |
| 335 | . |
| 336 | . int target_index; |
| 337 | . |
| 338 | . PTR used_by_bfd; |
| 339 | . |
| 340 | . {* If this is a constructor section then here is a list of the |
| 341 | . relocations created to relocate items within it. *} |
| 342 | . |
| 343 | . struct relent_chain *constructor_chain; |
| 344 | . |
| 345 | . {* The BFD which owns the section. *} |
| 346 | . |
| 347 | . bfd *owner; |
| 348 | . |
| 349 | . boolean reloc_done; |
| 350 | . {* A symbol which points at this section only *} |
| 351 | . struct symbol_cache_entry *symbol; |
| 352 | . struct symbol_cache_entry **symbol_ptr_ptr; |
| 353 | . struct bfd_seclet *seclets_head; |
| 354 | . struct bfd_seclet *seclets_tail; |
| 355 | .} asection ; |
| 356 | . |
| 357 | . |
| 358 | .#define BFD_ABS_SECTION_NAME "*ABS*" |
| 359 | .#define BFD_UND_SECTION_NAME "*UND*" |
| 360 | .#define BFD_COM_SECTION_NAME "*COM*" |
| 361 | .#define BFD_IND_SECTION_NAME "*IND*" |
| 362 | . |
| 363 | . {* the absolute section *} |
| 364 | . extern asection bfd_abs_section; |
| 365 | . {* Pointer to the undefined section *} |
| 366 | . extern asection bfd_und_section; |
| 367 | . {* Pointer to the common section *} |
| 368 | . extern asection bfd_com_section; |
| 369 | . {* Pointer to the indirect section *} |
| 370 | . extern asection bfd_ind_section; |
| 371 | . |
| 372 | . extern struct symbol_cache_entry *bfd_abs_symbol; |
| 373 | . extern struct symbol_cache_entry *bfd_com_symbol; |
| 374 | . extern struct symbol_cache_entry *bfd_und_symbol; |
| 375 | . extern struct symbol_cache_entry *bfd_ind_symbol; |
| 376 | .#define bfd_get_section_size_before_reloc(section) \ |
| 377 | . (section->reloc_done ? (abort(),1): (section)->_raw_size) |
| 378 | .#define bfd_get_section_size_after_reloc(section) \ |
| 379 | . ((section->reloc_done) ? (section)->_cooked_size: (abort(),1)) |
| 380 | */ |
| 381 | |
| 382 | /* These symbols are global, not specific to any BFD. Therefore, anything |
| 383 | that tries to change them is broken, and should be repaired. */ |
| 384 | static CONST asymbol global_syms[] = { |
| 385 | /* the_bfd, name, value, attr, section [, udata] */ |
| 386 | { 0, BFD_COM_SECTION_NAME, 0, BSF_SECTION_SYM, &bfd_com_section }, |
| 387 | { 0, BFD_UND_SECTION_NAME, 0, BSF_SECTION_SYM, &bfd_und_section }, |
| 388 | { 0, BFD_ABS_SECTION_NAME, 0, BSF_SECTION_SYM, &bfd_abs_section }, |
| 389 | { 0, BFD_IND_SECTION_NAME, 0, BSF_SECTION_SYM, &bfd_ind_section }, |
| 390 | }; |
| 391 | |
| 392 | #define STD_SECTION(SEC, FLAGS, SYM, NAME, IDX) \ |
| 393 | asymbol *SYM = (asymbol *) &global_syms[IDX]; \ |
| 394 | asection SEC = { NAME, 0, 0, FLAGS, 0, (boolean) 0, 0, 0, 0, &SEC,\ |
| 395 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (boolean) 0, \ |
| 396 | (asymbol *) &global_syms[IDX], &SYM, } |
| 397 | |
| 398 | STD_SECTION (bfd_com_section, SEC_IS_COMMON, bfd_com_symbol, BFD_COM_SECTION_NAME, 0); |
| 399 | STD_SECTION (bfd_und_section, 0, bfd_und_symbol, BFD_UND_SECTION_NAME, 1); |
| 400 | STD_SECTION (bfd_abs_section, 0, bfd_abs_symbol, BFD_ABS_SECTION_NAME, 2); |
| 401 | STD_SECTION (bfd_ind_section, 0, bfd_ind_symbol, BFD_IND_SECTION_NAME, 3); |
| 402 | #undef STD_SECTION |
| 403 | |
| 404 | /* |
| 405 | DOCDD |
| 406 | INODE |
| 407 | section prototypes, , typedef asection, Sections |
| 408 | SUBSECTION |
| 409 | section prototypes |
| 410 | |
| 411 | These are the functions exported by the section handling part of |
| 412 | <<libbfd>. |
| 413 | */ |
| 414 | |
| 415 | /* |
| 416 | FUNCTION |
| 417 | bfd_get_section_by_name |
| 418 | |
| 419 | SYNOPSIS |
| 420 | asection *bfd_get_section_by_name(bfd *abfd, CONST char *name); |
| 421 | |
| 422 | DESCRIPTION |
| 423 | Runs through the provided @var{abfd} and returns the |
| 424 | <<asection>> who's name matches that provided, otherwise NULL. |
| 425 | @xref{Sections}, for more information. |
| 426 | |
| 427 | */ |
| 428 | |
| 429 | asection * |
| 430 | DEFUN(bfd_get_section_by_name,(abfd, name), |
| 431 | bfd *abfd AND |
| 432 | CONST char *name) |
| 433 | { |
| 434 | asection *sect; |
| 435 | |
| 436 | for (sect = abfd->sections; sect != NULL; sect = sect->next) |
| 437 | if (!strcmp (sect->name, name)) return sect; |
| 438 | return NULL; |
| 439 | } |
| 440 | |
| 441 | |
| 442 | /* |
| 443 | FUNCTION |
| 444 | bfd_make_section_old_way |
| 445 | |
| 446 | SYNOPSIS |
| 447 | asection *bfd_make_section_old_way(bfd *, CONST char *name); |
| 448 | |
| 449 | DESCRIPTION |
| 450 | This function creates a new empty section called @var{name} |
| 451 | and attaches it to the end of the chain of sections for the |
| 452 | BFD supplied. An attempt to create a section with a name which |
| 453 | is already in use, returns its pointer without changing the |
| 454 | section chain. |
| 455 | |
| 456 | It has the funny name since this is the way it used to be |
| 457 | before is was rewritten... |
| 458 | |
| 459 | Possible errors are: |
| 460 | o invalid_operation - |
| 461 | If output has already started for this BFD. |
| 462 | o no_memory - |
| 463 | If obstack alloc fails. |
| 464 | |
| 465 | */ |
| 466 | |
| 467 | |
| 468 | asection * |
| 469 | DEFUN(bfd_make_section_old_way,(abfd, name), |
| 470 | bfd *abfd AND |
| 471 | CONST char * name) |
| 472 | { |
| 473 | asection *sec = bfd_get_section_by_name(abfd, name); |
| 474 | if (sec == (asection *)NULL) |
| 475 | { |
| 476 | sec = bfd_make_section(abfd, name); |
| 477 | } |
| 478 | return sec; |
| 479 | } |
| 480 | |
| 481 | |
| 482 | /* |
| 483 | FUNCTION |
| 484 | bfd_make_section |
| 485 | |
| 486 | SYNOPSIS |
| 487 | asection * bfd_make_section(bfd *, CONST char *name); |
| 488 | |
| 489 | DESCRIPTION |
| 490 | This function creates a new empty section called @var{name} |
| 491 | and attaches it to the end of the chain of sections for the |
| 492 | BFD supplied. An attempt to create a section with a name which |
| 493 | is already in use, returns NULL without changing the section |
| 494 | chain. |
| 495 | |
| 496 | Possible errors are: |
| 497 | o invalid_operation - If output has already started for this BFD. |
| 498 | o no_memory - If obstack alloc fails. |
| 499 | */ |
| 500 | |
| 501 | |
| 502 | |
| 503 | sec_ptr |
| 504 | DEFUN(bfd_make_section,(abfd, name), |
| 505 | bfd *abfd AND |
| 506 | CONST char * name) |
| 507 | { |
| 508 | asection *newsect; |
| 509 | asection ** prev = &abfd->sections; |
| 510 | asection * sect = abfd->sections; |
| 511 | |
| 512 | if (abfd->output_has_begun) { |
| 513 | bfd_error = invalid_operation; |
| 514 | return NULL; |
| 515 | } |
| 516 | |
| 517 | if (strcmp(name, BFD_ABS_SECTION_NAME) == 0) |
| 518 | { |
| 519 | return &bfd_abs_section; |
| 520 | } |
| 521 | if (strcmp(name, BFD_COM_SECTION_NAME) == 0) |
| 522 | { |
| 523 | return &bfd_com_section; |
| 524 | } |
| 525 | if (strcmp(name, BFD_UND_SECTION_NAME) == 0) |
| 526 | { |
| 527 | return &bfd_und_section; |
| 528 | } |
| 529 | |
| 530 | if (strcmp(name, BFD_IND_SECTION_NAME) == 0) |
| 531 | { |
| 532 | return &bfd_ind_section; |
| 533 | } |
| 534 | |
| 535 | while (sect) { |
| 536 | if (!strcmp(sect->name, name)) return NULL; |
| 537 | prev = §->next; |
| 538 | sect = sect->next; |
| 539 | } |
| 540 | |
| 541 | newsect = (asection *) bfd_zalloc(abfd, sizeof (asection)); |
| 542 | if (newsect == NULL) { |
| 543 | bfd_error = no_memory; |
| 544 | return NULL; |
| 545 | } |
| 546 | |
| 547 | newsect->name = name; |
| 548 | newsect->index = abfd->section_count++; |
| 549 | newsect->flags = SEC_NO_FLAGS; |
| 550 | |
| 551 | newsect->userdata = 0; |
| 552 | newsect->next = (asection *)NULL; |
| 553 | newsect->relocation = (arelent *)NULL; |
| 554 | newsect->reloc_count = 0; |
| 555 | newsect->line_filepos =0; |
| 556 | newsect->owner = abfd; |
| 557 | |
| 558 | /* Create a symbol whos only job is to point to this section. This is |
| 559 | useful for things like relocs which are relative to the base of a |
| 560 | section. */ |
| 561 | newsect->symbol = bfd_make_empty_symbol(abfd); |
| 562 | newsect->symbol->name = name; |
| 563 | newsect->symbol->value = 0; |
| 564 | newsect->symbol->section = newsect; |
| 565 | newsect->symbol->flags = BSF_SECTION_SYM; |
| 566 | |
| 567 | |
| 568 | newsect->symbol_ptr_ptr = &newsect->symbol; |
| 569 | |
| 570 | if (BFD_SEND (abfd, _new_section_hook, (abfd, newsect)) != true) { |
| 571 | free (newsect); |
| 572 | return NULL; |
| 573 | } |
| 574 | |
| 575 | *prev = newsect; |
| 576 | return newsect; |
| 577 | } |
| 578 | |
| 579 | |
| 580 | /* |
| 581 | FUNCTION |
| 582 | bfd_set_section_flags |
| 583 | |
| 584 | SYNOPSIS |
| 585 | boolean bfd_set_section_flags(bfd *, asection *, flagword); |
| 586 | |
| 587 | DESCRIPTION |
| 588 | Attempts to set the attributes of the section named in the BFD |
| 589 | supplied to the value. Returns true on success, false on |
| 590 | error. Possible error returns are: |
| 591 | |
| 592 | o invalid operation - |
| 593 | The section cannot have one or more of the attributes |
| 594 | requested. For example, a .bss section in <<a.out>> may not |
| 595 | have the <<SEC_HAS_CONTENTS>> field set. |
| 596 | |
| 597 | */ |
| 598 | |
| 599 | boolean |
| 600 | DEFUN(bfd_set_section_flags,(abfd, section, flags), |
| 601 | bfd *abfd AND |
| 602 | sec_ptr section AND |
| 603 | flagword flags) |
| 604 | { |
| 605 | #if 0 |
| 606 | /* If you try to copy a text section from an input file (where it |
| 607 | has the SEC_CODE flag set) to an output file, this loses big if |
| 608 | the bfd_applicable_section_flags (abfd) doesn't have the SEC_CODE |
| 609 | set - which it doesn't, at least not for a.out. FIXME */ |
| 610 | |
| 611 | if ((flags & bfd_applicable_section_flags (abfd)) != flags) { |
| 612 | bfd_error = invalid_operation; |
| 613 | return false; |
| 614 | } |
| 615 | #endif |
| 616 | |
| 617 | section->flags = flags; |
| 618 | return true; |
| 619 | } |
| 620 | |
| 621 | |
| 622 | /* |
| 623 | FUNCTION |
| 624 | bfd_map_over_sections |
| 625 | |
| 626 | SYNOPSIS |
| 627 | void bfd_map_over_sections(bfd *abfd, |
| 628 | void (*func)(bfd *abfd, |
| 629 | asection *sect, |
| 630 | PTR obj), |
| 631 | PTR obj); |
| 632 | |
| 633 | DESCRIPTION |
| 634 | Calls the provided function @var{func} for each section |
| 635 | attached to the BFD @var{abfd}, passing @var{obj} as an |
| 636 | argument. The function will be called as if by |
| 637 | |
| 638 | | func(abfd, the_section, obj); |
| 639 | |
| 640 | This is the prefered method for iterating over sections, an |
| 641 | alternative would be to use a loop: |
| 642 | |
| 643 | | section *p; |
| 644 | | for (p = abfd->sections; p != NULL; p = p->next) |
| 645 | | func(abfd, p, ...) |
| 646 | |
| 647 | |
| 648 | */ |
| 649 | |
| 650 | /*VARARGS2*/ |
| 651 | void |
| 652 | DEFUN(bfd_map_over_sections,(abfd, operation, user_storage), |
| 653 | bfd *abfd AND |
| 654 | void (*operation) PARAMS ((bfd *abfd, asection *sect, PTR obj)) AND |
| 655 | PTR user_storage) |
| 656 | { |
| 657 | asection *sect; |
| 658 | int i = 0; |
| 659 | |
| 660 | for (sect = abfd->sections; sect != NULL; i++, sect = sect->next) |
| 661 | (*operation) (abfd, sect, user_storage); |
| 662 | |
| 663 | if (i != abfd->section_count) /* Debugging */ |
| 664 | abort(); |
| 665 | } |
| 666 | |
| 667 | |
| 668 | /* |
| 669 | FUNCTION |
| 670 | bfd_set_section_size |
| 671 | |
| 672 | SYNOPSIS |
| 673 | boolean bfd_set_section_size(bfd *, asection *, bfd_size_type val); |
| 674 | |
| 675 | DESCRIPTION |
| 676 | Sets @var{section} to the size @var{val}. If the operation is |
| 677 | ok, then <<true>> is returned, else <<false>>. |
| 678 | |
| 679 | Possible error returns: |
| 680 | o invalid_operation - |
| 681 | Writing has started to the BFD, so setting the size is invalid |
| 682 | |
| 683 | */ |
| 684 | |
| 685 | boolean |
| 686 | DEFUN(bfd_set_section_size,(abfd, ptr, val), |
| 687 | bfd *abfd AND |
| 688 | sec_ptr ptr AND |
| 689 | bfd_size_type val) |
| 690 | { |
| 691 | /* Once you've started writing to any section you cannot create or change |
| 692 | the size of any others. */ |
| 693 | |
| 694 | if (abfd->output_has_begun) { |
| 695 | bfd_error = invalid_operation; |
| 696 | return false; |
| 697 | } |
| 698 | |
| 699 | ptr->_cooked_size = val; |
| 700 | ptr->_raw_size = val; |
| 701 | |
| 702 | return true; |
| 703 | } |
| 704 | |
| 705 | /* |
| 706 | FUNCTION |
| 707 | bfd_set_section_contents |
| 708 | |
| 709 | SYNOPSIS |
| 710 | boolean bfd_set_section_contents |
| 711 | (bfd *abfd, |
| 712 | asection *section, |
| 713 | PTR data, |
| 714 | file_ptr offset, |
| 715 | bfd_size_type count); |
| 716 | |
| 717 | |
| 718 | DESCRIPTION |
| 719 | Sets the contents of the section @var{section} in BFD |
| 720 | @var{abfd} to the data starting in memory at @var{data}. The |
| 721 | data is written to the output section starting at offset |
| 722 | @var{offset} for @var{count} bytes. |
| 723 | |
| 724 | |
| 725 | |
| 726 | Normally <<true>> is returned, else <<false>>. Possible error |
| 727 | returns are: |
| 728 | o no_contents - |
| 729 | The output section does not have the <<SEC_HAS_CONTENTS>> |
| 730 | attribute, so nothing can be written to it. |
| 731 | o and some more too |
| 732 | |
| 733 | This routine is front end to the back end function |
| 734 | <<_bfd_set_section_contents>>. |
| 735 | |
| 736 | |
| 737 | */ |
| 738 | |
| 739 | #define bfd_get_section_size_now(abfd,sec) \ |
| 740 | (sec->reloc_done \ |
| 741 | ? bfd_get_section_size_after_reloc (sec) \ |
| 742 | : bfd_get_section_size_before_reloc (sec)) |
| 743 | |
| 744 | boolean |
| 745 | DEFUN(bfd_set_section_contents,(abfd, section, location, offset, count), |
| 746 | bfd *abfd AND |
| 747 | sec_ptr section AND |
| 748 | PTR location AND |
| 749 | file_ptr offset AND |
| 750 | bfd_size_type count) |
| 751 | { |
| 752 | bfd_size_type sz; |
| 753 | |
| 754 | if (!bfd_get_section_flags(abfd, section) & SEC_HAS_CONTENTS) |
| 755 | { |
| 756 | bfd_error = no_contents; |
| 757 | return(false); |
| 758 | } |
| 759 | |
| 760 | if (offset < 0 || count < 0) |
| 761 | { |
| 762 | bad_val: |
| 763 | bfd_error = bad_value; |
| 764 | return false; |
| 765 | } |
| 766 | sz = bfd_get_section_size_now (abfd, section); |
| 767 | if (offset > sz |
| 768 | || count > sz |
| 769 | || offset + count > sz) |
| 770 | goto bad_val; |
| 771 | |
| 772 | if (BFD_SEND (abfd, _bfd_set_section_contents, |
| 773 | (abfd, section, location, offset, count))) |
| 774 | { |
| 775 | abfd->output_has_begun = true; |
| 776 | return true; |
| 777 | } |
| 778 | |
| 779 | return false; |
| 780 | } |
| 781 | |
| 782 | /* |
| 783 | FUNCTION |
| 784 | bfd_get_section_contents |
| 785 | |
| 786 | SYNOPSIS |
| 787 | boolean bfd_get_section_contents |
| 788 | (bfd *abfd, asection *section, PTR location, |
| 789 | file_ptr offset, bfd_size_type count); |
| 790 | |
| 791 | DESCRIPTION |
| 792 | This function reads data from @var{section} in BFD @var{abfd} |
| 793 | into memory starting at @var{location}. The data is read at an |
| 794 | offset of @var{offset} from the start of the input section, |
| 795 | and is read for @var{count} bytes. |
| 796 | |
| 797 | If the contents of a constuctor with the <<SEC_CONSTUCTOR>> |
| 798 | flag set are requested, then the @var{location} is filled with |
| 799 | zeroes. If no errors occur, <<true>> is returned, else |
| 800 | <<false>>. |
| 801 | |
| 802 | |
| 803 | |
| 804 | */ |
| 805 | boolean |
| 806 | DEFUN(bfd_get_section_contents,(abfd, section, location, offset, count), |
| 807 | bfd *abfd AND |
| 808 | sec_ptr section AND |
| 809 | PTR location AND |
| 810 | file_ptr offset AND |
| 811 | bfd_size_type count) |
| 812 | { |
| 813 | bfd_size_type sz; |
| 814 | |
| 815 | if (section->flags & SEC_CONSTRUCTOR) |
| 816 | { |
| 817 | memset(location, 0, (unsigned)count); |
| 818 | return true; |
| 819 | } |
| 820 | |
| 821 | if (offset < 0 || count < 0) |
| 822 | { |
| 823 | bad_val: |
| 824 | bfd_error = bad_value; |
| 825 | return false; |
| 826 | } |
| 827 | sz = bfd_get_section_size_now (abfd, section); |
| 828 | if (offset > sz |
| 829 | || count > sz |
| 830 | || offset + count > sz) |
| 831 | goto bad_val; |
| 832 | |
| 833 | if (count == 0) |
| 834 | /* Don't bother. */ |
| 835 | return true; |
| 836 | |
| 837 | return BFD_SEND (abfd, _bfd_get_section_contents, |
| 838 | (abfd, section, location, offset, count)); |
| 839 | } |