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      1 /* Object file "section" support for the BFD library.
      2    Copyright (C) 1990-2014 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 3 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., 51 Franklin Street - Fifth Floor, Boston,
     20    MA 02110-1301, USA.  */
     21 
     22 /*
     23 SECTION
     24 	Sections
     25 
     26 	The raw data contained within a BFD is maintained through the
     27 	section abstraction.  A single BFD may have any number of
     28 	sections.  It keeps hold of them by pointing to the first;
     29 	each one points to the next in the list.
     30 
     31 	Sections are supported in BFD in <<section.c>>.
     32 
     33 @menu
     34 @* Section Input::
     35 @* Section Output::
     36 @* typedef asection::
     37 @* section prototypes::
     38 @end menu
     39 
     40 INODE
     41 Section Input, Section Output, Sections, Sections
     42 SUBSECTION
     43 	Section input
     44 
     45 	When a BFD is opened for reading, the section structures are
     46 	created and attached to the BFD.
     47 
     48 	Each section has a name which describes the section in the
     49 	outside world---for example, <<a.out>> would contain at least
     50 	three sections, called <<.text>>, <<.data>> and <<.bss>>.
     51 
     52 	Names need not be unique; for example a COFF file may have several
     53 	sections named <<.data>>.
     54 
     55 	Sometimes a BFD will contain more than the ``natural'' number of
     56 	sections. A back end may attach other sections containing
     57 	constructor data, or an application may add a section (using
     58 	<<bfd_make_section>>) to the sections attached to an already open
     59 	BFD. For example, the linker creates an extra section
     60 	<<COMMON>> for each input file's BFD to hold information about
     61 	common storage.
     62 
     63 	The raw data is not necessarily read in when
     64 	the section descriptor is created. Some targets may leave the
     65 	data in place until a <<bfd_get_section_contents>> call is
     66 	made. Other back ends may read in all the data at once.  For
     67 	example, an S-record file has to be read once to determine the
     68 	size of the data. An IEEE-695 file doesn't contain raw data in
     69 	sections, but data and relocation expressions intermixed, so
     70 	the data area has to be parsed to get out the data and
     71 	relocations.
     72 
     73 INODE
     74 Section Output, typedef asection, Section Input, Sections
     75 
     76 SUBSECTION
     77 	Section output
     78 
     79 	To write a new object style BFD, the various sections to be
     80 	written have to be created. They are attached to the BFD in
     81 	the same way as input sections; data is written to the
     82 	sections using <<bfd_set_section_contents>>.
     83 
     84 	Any program that creates or combines sections (e.g., the assembler
     85 	and linker) must use the <<asection>> fields <<output_section>> and
     86 	<<output_offset>> to indicate the file sections to which each
     87 	section must be written.  (If the section is being created from
     88 	scratch, <<output_section>> should probably point to the section
     89 	itself and <<output_offset>> should probably be zero.)
     90 
     91 	The data to be written comes from input sections attached
     92 	(via <<output_section>> pointers) to
     93 	the output sections.  The output section structure can be
     94 	considered a filter for the input section: the output section
     95 	determines the vma of the output data and the name, but the
     96 	input section determines the offset into the output section of
     97 	the data to be written.
     98 
     99 	E.g., to create a section "O", starting at 0x100, 0x123 long,
    100 	containing two subsections, "A" at offset 0x0 (i.e., at vma
    101 	0x100) and "B" at offset 0x20 (i.e., at vma 0x120) the <<asection>>
    102 	structures would look like:
    103 
    104 |   section name          "A"
    105 |     output_offset   0x00
    106 |     size            0x20
    107 |     output_section ----------->  section name    "O"
    108 |                             |    vma             0x100
    109 |   section name          "B" |    size            0x123
    110 |     output_offset   0x20    |
    111 |     size            0x103   |
    112 |     output_section  --------|
    113 
    114 SUBSECTION
    115 	Link orders
    116 
    117 	The data within a section is stored in a @dfn{link_order}.
    118 	These are much like the fixups in <<gas>>.  The link_order
    119 	abstraction allows a section to grow and shrink within itself.
    120 
    121 	A link_order knows how big it is, and which is the next
    122 	link_order and where the raw data for it is; it also points to
    123 	a list of relocations which apply to it.
    124 
    125 	The link_order is used by the linker to perform relaxing on
    126 	final code.  The compiler creates code which is as big as
    127 	necessary to make it work without relaxing, and the user can
    128 	select whether to relax.  Sometimes relaxing takes a lot of
    129 	time.  The linker runs around the relocations to see if any
    130 	are attached to data which can be shrunk, if so it does it on
    131 	a link_order by link_order basis.
    132 
    133 */
    134 
    135 #include "sysdep.h"
    136 #include "bfd.h"
    137 #include "libbfd.h"
    138 #include "bfdlink.h"
    139 
    140 /*
    141 DOCDD
    142 INODE
    143 typedef asection, section prototypes, Section Output, Sections
    144 SUBSECTION
    145 	typedef asection
    146 
    147 	Here is the section structure:
    148 
    149 CODE_FRAGMENT
    150 .
    151 .typedef struct bfd_section
    152 .{
    153 .  {* The name of the section; the name isn't a copy, the pointer is
    154 .     the same as that passed to bfd_make_section.  *}
    155 .  const char *name;
    156 .
    157 .  {* A unique sequence number.  *}
    158 .  int id;
    159 .
    160 .  {* Which section in the bfd; 0..n-1 as sections are created in a bfd.  *}
    161 .  int index;
    162 .
    163 .  {* The next section in the list belonging to the BFD, or NULL.  *}
    164 .  struct bfd_section *next;
    165 .
    166 .  {* The previous section in the list belonging to the BFD, or NULL.  *}
    167 .  struct bfd_section *prev;
    168 .
    169 .  {* The field flags contains attributes of the section. Some
    170 .     flags are read in from the object file, and some are
    171 .     synthesized from other information.  *}
    172 .  flagword flags;
    173 .
    174 .#define SEC_NO_FLAGS   0x000
    175 .
    176 .  {* Tells the OS to allocate space for this section when loading.
    177 .     This is clear for a section containing debug information only.  *}
    178 .#define SEC_ALLOC      0x001
    179 .
    180 .  {* Tells the OS to load the section from the file when loading.
    181 .     This is clear for a .bss section.  *}
    182 .#define SEC_LOAD       0x002
    183 .
    184 .  {* The section contains data still to be relocated, so there is
    185 .     some relocation information too.  *}
    186 .#define SEC_RELOC      0x004
    187 .
    188 .  {* A signal to the OS that the section contains read only data.  *}
    189 .#define SEC_READONLY   0x008
    190 .
    191 .  {* The section contains code only.  *}
    192 .#define SEC_CODE       0x010
    193 .
    194 .  {* The section contains data only.  *}
    195 .#define SEC_DATA       0x020
    196 .
    197 .  {* The section will reside in ROM.  *}
    198 .#define SEC_ROM        0x040
    199 .
    200 .  {* The section contains constructor information. This section
    201 .     type is used by the linker to create lists of constructors and
    202 .     destructors used by <<g++>>. When a back end sees a symbol
    203 .     which should be used in a constructor list, it creates a new
    204 .     section for the type of name (e.g., <<__CTOR_LIST__>>), attaches
    205 .     the symbol to it, and builds a relocation. To build the lists
    206 .     of constructors, all the linker has to do is catenate all the
    207 .     sections called <<__CTOR_LIST__>> and relocate the data
    208 .     contained within - exactly the operations it would peform on
    209 .     standard data.  *}
    210 .#define SEC_CONSTRUCTOR 0x080
    211 .
    212 .  {* The section has contents - a data section could be
    213 .     <<SEC_ALLOC>> | <<SEC_HAS_CONTENTS>>; a debug section could be
    214 .     <<SEC_HAS_CONTENTS>>  *}
    215 .#define SEC_HAS_CONTENTS 0x100
    216 .
    217 .  {* An instruction to the linker to not output the section
    218 .     even if it has information which would normally be written.  *}
    219 .#define SEC_NEVER_LOAD 0x200
    220 .
    221 .  {* The section contains thread local data.  *}
    222 .#define SEC_THREAD_LOCAL 0x400
    223 .
    224 .  {* The section has GOT references.  This flag is only for the
    225 .     linker, and is currently only used by the elf32-hppa back end.
    226 .     It will be set if global offset table references were detected
    227 .     in this section, which indicate to the linker that the section
    228 .     contains PIC code, and must be handled specially when doing a
    229 .     static link.  *}
    230 .#define SEC_HAS_GOT_REF 0x800
    231 .
    232 .  {* The section contains common symbols (symbols may be defined
    233 .     multiple times, the value of a symbol is the amount of
    234 .     space it requires, and the largest symbol value is the one
    235 .     used).  Most targets have exactly one of these (which we
    236 .     translate to bfd_com_section_ptr), but ECOFF has two.  *}
    237 .#define SEC_IS_COMMON 0x1000
    238 .
    239 .  {* The section contains only debugging information.  For
    240 .     example, this is set for ELF .debug and .stab sections.
    241 .     strip tests this flag to see if a section can be
    242 .     discarded.  *}
    243 .#define SEC_DEBUGGING 0x2000
    244 .
    245 .  {* The contents of this section are held in memory pointed to
    246 .     by the contents field.  This is checked by bfd_get_section_contents,
    247 .     and the data is retrieved from memory if appropriate.  *}
    248 .#define SEC_IN_MEMORY 0x4000
    249 .
    250 .  {* The contents of this section are to be excluded by the
    251 .     linker for executable and shared objects unless those
    252 .     objects are to be further relocated.  *}
    253 .#define SEC_EXCLUDE 0x8000
    254 .
    255 .  {* The contents of this section are to be sorted based on the sum of
    256 .     the symbol and addend values specified by the associated relocation
    257 .     entries.  Entries without associated relocation entries will be
    258 .     appended to the end of the section in an unspecified order.  *}
    259 .#define SEC_SORT_ENTRIES 0x10000
    260 .
    261 .  {* When linking, duplicate sections of the same name should be
    262 .     discarded, rather than being combined into a single section as
    263 .     is usually done.  This is similar to how common symbols are
    264 .     handled.  See SEC_LINK_DUPLICATES below.  *}
    265 .#define SEC_LINK_ONCE 0x20000
    266 .
    267 .  {* If SEC_LINK_ONCE is set, this bitfield describes how the linker
    268 .     should handle duplicate sections.  *}
    269 .#define SEC_LINK_DUPLICATES 0xc0000
    270 .
    271 .  {* This value for SEC_LINK_DUPLICATES means that duplicate
    272 .     sections with the same name should simply be discarded.  *}
    273 .#define SEC_LINK_DUPLICATES_DISCARD 0x0
    274 .
    275 .  {* This value for SEC_LINK_DUPLICATES means that the linker
    276 .     should warn if there are any duplicate sections, although
    277 .     it should still only link one copy.  *}
    278 .#define SEC_LINK_DUPLICATES_ONE_ONLY 0x40000
    279 .
    280 .  {* This value for SEC_LINK_DUPLICATES means that the linker
    281 .     should warn if any duplicate sections are a different size.  *}
    282 .#define SEC_LINK_DUPLICATES_SAME_SIZE 0x80000
    283 .
    284 .  {* This value for SEC_LINK_DUPLICATES means that the linker
    285 .     should warn if any duplicate sections contain different
    286 .     contents.  *}
    287 .#define SEC_LINK_DUPLICATES_SAME_CONTENTS \
    288 .  (SEC_LINK_DUPLICATES_ONE_ONLY | SEC_LINK_DUPLICATES_SAME_SIZE)
    289 .
    290 .  {* This section was created by the linker as part of dynamic
    291 .     relocation or other arcane processing.  It is skipped when
    292 .     going through the first-pass output, trusting that someone
    293 .     else up the line will take care of it later.  *}
    294 .#define SEC_LINKER_CREATED 0x100000
    295 .
    296 .  {* This section should not be subject to garbage collection.
    297 .     Also set to inform the linker that this section should not be
    298 .     listed in the link map as discarded.  *}
    299 .#define SEC_KEEP 0x200000
    300 .
    301 .  {* This section contains "short" data, and should be placed
    302 .     "near" the GP.  *}
    303 .#define SEC_SMALL_DATA 0x400000
    304 .
    305 .  {* Attempt to merge identical entities in the section.
    306 .     Entity size is given in the entsize field.  *}
    307 .#define SEC_MERGE 0x800000
    308 .
    309 .  {* If given with SEC_MERGE, entities to merge are zero terminated
    310 .     strings where entsize specifies character size instead of fixed
    311 .     size entries.  *}
    312 .#define SEC_STRINGS 0x1000000
    313 .
    314 .  {* This section contains data about section groups.  *}
    315 .#define SEC_GROUP 0x2000000
    316 .
    317 .  {* The section is a COFF shared library section.  This flag is
    318 .     only for the linker.  If this type of section appears in
    319 .     the input file, the linker must copy it to the output file
    320 .     without changing the vma or size.  FIXME: Although this
    321 .     was originally intended to be general, it really is COFF
    322 .     specific (and the flag was renamed to indicate this).  It
    323 .     might be cleaner to have some more general mechanism to
    324 .     allow the back end to control what the linker does with
    325 .     sections.  *}
    326 .#define SEC_COFF_SHARED_LIBRARY 0x4000000
    327 .
    328 .  {* This input section should be copied to output in reverse order
    329 .     as an array of pointers.  This is for ELF linker internal use
    330 .     only.  *}
    331 .#define SEC_ELF_REVERSE_COPY 0x4000000
    332 .
    333 .  {* This section contains data which may be shared with other
    334 .     executables or shared objects. This is for COFF only.  *}
    335 .#define SEC_COFF_SHARED 0x8000000
    336 .
    337 .  {* When a section with this flag is being linked, then if the size of
    338 .     the input section is less than a page, it should not cross a page
    339 .     boundary.  If the size of the input section is one page or more,
    340 .     it should be aligned on a page boundary.  This is for TI
    341 .     TMS320C54X only.  *}
    342 .#define SEC_TIC54X_BLOCK 0x10000000
    343 .
    344 .  {* Conditionally link this section; do not link if there are no
    345 .     references found to any symbol in the section.  This is for TI
    346 .     TMS320C54X only.  *}
    347 .#define SEC_TIC54X_CLINK 0x20000000
    348 .
    349 .  {* Indicate that section has the no read flag set. This happens
    350 .     when memory read flag isn't set. *}
    351 .#define SEC_COFF_NOREAD 0x40000000
    352 .
    353 .  {*  End of section flags.  *}
    354 .
    355 .  {* Some internal packed boolean fields.  *}
    356 .
    357 .  {* See the vma field.  *}
    358 .  unsigned int user_set_vma : 1;
    359 .
    360 .  {* A mark flag used by some of the linker backends.  *}
    361 .  unsigned int linker_mark : 1;
    362 .
    363 .  {* Another mark flag used by some of the linker backends.  Set for
    364 .     output sections that have an input section.  *}
    365 .  unsigned int linker_has_input : 1;
    366 .
    367 .  {* Mark flag used by some linker backends for garbage collection.  *}
    368 .  unsigned int gc_mark : 1;
    369 .
    370 .  {* Section compression status.  *}
    371 .  unsigned int compress_status : 2;
    372 .#define COMPRESS_SECTION_NONE    0
    373 .#define COMPRESS_SECTION_DONE    1
    374 .#define DECOMPRESS_SECTION_SIZED 2
    375 .
    376 .  {* The following flags are used by the ELF linker. *}
    377 .
    378 .  {* Mark sections which have been allocated to segments.  *}
    379 .  unsigned int segment_mark : 1;
    380 .
    381 .  {* Type of sec_info information.  *}
    382 .  unsigned int sec_info_type:3;
    383 .#define SEC_INFO_TYPE_NONE      0
    384 .#define SEC_INFO_TYPE_STABS     1
    385 .#define SEC_INFO_TYPE_MERGE     2
    386 .#define SEC_INFO_TYPE_EH_FRAME  3
    387 .#define SEC_INFO_TYPE_JUST_SYMS 4
    388 .#define SEC_INFO_TYPE_TARGET    5
    389 .
    390 .  {* Nonzero if this section uses RELA relocations, rather than REL.  *}
    391 .  unsigned int use_rela_p:1;
    392 .
    393 .  {* Bits used by various backends.  The generic code doesn't touch
    394 .     these fields.  *}
    395 .
    396 .  unsigned int sec_flg0:1;
    397 .  unsigned int sec_flg1:1;
    398 .  unsigned int sec_flg2:1;
    399 .  unsigned int sec_flg3:1;
    400 .  unsigned int sec_flg4:1;
    401 .  unsigned int sec_flg5:1;
    402 .
    403 .  {* End of internal packed boolean fields.  *}
    404 .
    405 .  {*  The virtual memory address of the section - where it will be
    406 .      at run time.  The symbols are relocated against this.  The
    407 .      user_set_vma flag is maintained by bfd; if it's not set, the
    408 .      backend can assign addresses (for example, in <<a.out>>, where
    409 .      the default address for <<.data>> is dependent on the specific
    410 .      target and various flags).  *}
    411 .  bfd_vma vma;
    412 .
    413 .  {*  The load address of the section - where it would be in a
    414 .      rom image; really only used for writing section header
    415 .      information.  *}
    416 .  bfd_vma lma;
    417 .
    418 .  {* The size of the section in octets, as it will be output.
    419 .     Contains a value even if the section has no contents (e.g., the
    420 .     size of <<.bss>>).  *}
    421 .  bfd_size_type size;
    422 .
    423 .  {* For input sections, the original size on disk of the section, in
    424 .     octets.  This field should be set for any section whose size is
    425 .     changed by linker relaxation.  It is required for sections where
    426 .     the linker relaxation scheme doesn't cache altered section and
    427 .     reloc contents (stabs, eh_frame, SEC_MERGE, some coff relaxing
    428 .     targets), and thus the original size needs to be kept to read the
    429 .     section multiple times.  For output sections, rawsize holds the
    430 .     section size calculated on a previous linker relaxation pass.  *}
    431 .  bfd_size_type rawsize;
    432 .
    433 .  {* The compressed size of the section in octets.  *}
    434 .  bfd_size_type compressed_size;
    435 .
    436 .  {* Relaxation table. *}
    437 .  struct relax_table *relax;
    438 .
    439 .  {* Count of used relaxation table entries. *}
    440 .  int relax_count;
    441 .
    442 .
    443 .  {* If this section is going to be output, then this value is the
    444 .     offset in *bytes* into the output section of the first byte in the
    445 .     input section (byte ==> smallest addressable unit on the
    446 .     target).  In most cases, if this was going to start at the
    447 .     100th octet (8-bit quantity) in the output section, this value
    448 .     would be 100.  However, if the target byte size is 16 bits
    449 .     (bfd_octets_per_byte is "2"), this value would be 50.  *}
    450 .  bfd_vma output_offset;
    451 .
    452 .  {* The output section through which to map on output.  *}
    453 .  struct bfd_section *output_section;
    454 .
    455 .  {* The alignment requirement of the section, as an exponent of 2 -
    456 .     e.g., 3 aligns to 2^3 (or 8).  *}
    457 .  unsigned int alignment_power;
    458 .
    459 .  {* If an input section, a pointer to a vector of relocation
    460 .     records for the data in this section.  *}
    461 .  struct reloc_cache_entry *relocation;
    462 .
    463 .  {* If an output section, a pointer to a vector of pointers to
    464 .     relocation records for the data in this section.  *}
    465 .  struct reloc_cache_entry **orelocation;
    466 .
    467 .  {* The number of relocation records in one of the above.  *}
    468 .  unsigned reloc_count;
    469 .
    470 .  {* Information below is back end specific - and not always used
    471 .     or updated.  *}
    472 .
    473 .  {* File position of section data.  *}
    474 .  file_ptr filepos;
    475 .
    476 .  {* File position of relocation info.  *}
    477 .  file_ptr rel_filepos;
    478 .
    479 .  {* File position of line data.  *}
    480 .  file_ptr line_filepos;
    481 .
    482 .  {* Pointer to data for applications.  *}
    483 .  void *userdata;
    484 .
    485 .  {* If the SEC_IN_MEMORY flag is set, this points to the actual
    486 .     contents.  *}
    487 .  unsigned char *contents;
    488 .
    489 .  {* Attached line number information.  *}
    490 .  alent *lineno;
    491 .
    492 .  {* Number of line number records.  *}
    493 .  unsigned int lineno_count;
    494 .
    495 .  {* Entity size for merging purposes.  *}
    496 .  unsigned int entsize;
    497 .
    498 .  {* Points to the kept section if this section is a link-once section,
    499 .     and is discarded.  *}
    500 .  struct bfd_section *kept_section;
    501 .
    502 .  {* When a section is being output, this value changes as more
    503 .     linenumbers are written out.  *}
    504 .  file_ptr moving_line_filepos;
    505 .
    506 .  {* What the section number is in the target world.  *}
    507 .  int target_index;
    508 .
    509 .  void *used_by_bfd;
    510 .
    511 .  {* If this is a constructor section then here is a list of the
    512 .     relocations created to relocate items within it.  *}
    513 .  struct relent_chain *constructor_chain;
    514 .
    515 .  {* The BFD which owns the section.  *}
    516 .  bfd *owner;
    517 .
    518 .  {* A symbol which points at this section only.  *}
    519 .  struct bfd_symbol *symbol;
    520 .  struct bfd_symbol **symbol_ptr_ptr;
    521 .
    522 .  {* Early in the link process, map_head and map_tail are used to build
    523 .     a list of input sections attached to an output section.  Later,
    524 .     output sections use these fields for a list of bfd_link_order
    525 .     structs.  *}
    526 .  union {
    527 .    struct bfd_link_order *link_order;
    528 .    struct bfd_section *s;
    529 .  } map_head, map_tail;
    530 .} asection;
    531 .
    532 .{* Relax table contains information about instructions which can
    533 .   be removed by relaxation -- replacing a long address with a
    534 .   short address.  *}
    535 .struct relax_table {
    536 .  {* Address where bytes may be deleted. *}
    537 .  bfd_vma addr;
    538 .
    539 .  {* Number of bytes to be deleted.  *}
    540 .  int size;
    541 .};
    542 .
    543 .{* Note: the following are provided as inline functions rather than macros
    544 .   because not all callers use the return value.  A macro implementation
    545 .   would use a comma expression, eg: "((ptr)->foo = val, TRUE)" and some
    546 .   compilers will complain about comma expressions that have no effect.  *}
    547 .static inline bfd_boolean
    548 .bfd_set_section_userdata (bfd * abfd ATTRIBUTE_UNUSED, asection * ptr, void * val)
    549 .{
    550 .  ptr->userdata = val;
    551 .  return TRUE;
    552 .}
    553 .
    554 .static inline bfd_boolean
    555 .bfd_set_section_vma (bfd * abfd ATTRIBUTE_UNUSED, asection * ptr, bfd_vma val)
    556 .{
    557 .  ptr->vma = ptr->lma = val;
    558 .  ptr->user_set_vma = TRUE;
    559 .  return TRUE;
    560 .}
    561 .
    562 .static inline bfd_boolean
    563 .bfd_set_section_alignment (bfd * abfd ATTRIBUTE_UNUSED, asection * ptr, unsigned int val)
    564 .{
    565 .  ptr->alignment_power = val;
    566 .  return TRUE;
    567 .}
    568 .
    569 .{* These sections are global, and are managed by BFD.  The application
    570 .   and target back end are not permitted to change the values in
    571 .   these sections.  *}
    572 .extern asection _bfd_std_section[4];
    573 .
    574 .#define BFD_ABS_SECTION_NAME "*ABS*"
    575 .#define BFD_UND_SECTION_NAME "*UND*"
    576 .#define BFD_COM_SECTION_NAME "*COM*"
    577 .#define BFD_IND_SECTION_NAME "*IND*"
    578 .
    579 .{* Pointer to the common section.  *}
    580 .#define bfd_com_section_ptr (&_bfd_std_section[0])
    581 .{* Pointer to the undefined section.  *}
    582 .#define bfd_und_section_ptr (&_bfd_std_section[1])
    583 .{* Pointer to the absolute section.  *}
    584 .#define bfd_abs_section_ptr (&_bfd_std_section[2])
    585 .{* Pointer to the indirect section.  *}
    586 .#define bfd_ind_section_ptr (&_bfd_std_section[3])
    587 .
    588 .#define bfd_is_und_section(sec) ((sec) == bfd_und_section_ptr)
    589 .#define bfd_is_abs_section(sec) ((sec) == bfd_abs_section_ptr)
    590 .#define bfd_is_ind_section(sec) ((sec) == bfd_ind_section_ptr)
    591 .
    592 .#define bfd_is_const_section(SEC)		\
    593 . (   ((SEC) == bfd_abs_section_ptr)		\
    594 .  || ((SEC) == bfd_und_section_ptr)		\
    595 .  || ((SEC) == bfd_com_section_ptr)		\
    596 .  || ((SEC) == bfd_ind_section_ptr))
    597 .
    598 .{* Macros to handle insertion and deletion of a bfd's sections.  These
    599 .   only handle the list pointers, ie. do not adjust section_count,
    600 .   target_index etc.  *}
    601 .#define bfd_section_list_remove(ABFD, S) \
    602 .  do							\
    603 .    {							\
    604 .      asection *_s = S;				\
    605 .      asection *_next = _s->next;			\
    606 .      asection *_prev = _s->prev;			\
    607 .      if (_prev)					\
    608 .        _prev->next = _next;				\
    609 .      else						\
    610 .        (ABFD)->sections = _next;			\
    611 .      if (_next)					\
    612 .        _next->prev = _prev;				\
    613 .      else						\
    614 .        (ABFD)->section_last = _prev;			\
    615 .    }							\
    616 .  while (0)
    617 .#define bfd_section_list_append(ABFD, S) \
    618 .  do							\
    619 .    {							\
    620 .      asection *_s = S;				\
    621 .      bfd *_abfd = ABFD;				\
    622 .      _s->next = NULL;					\
    623 .      if (_abfd->section_last)				\
    624 .        {						\
    625 .          _s->prev = _abfd->section_last;		\
    626 .          _abfd->section_last->next = _s;		\
    627 .        }						\
    628 .      else						\
    629 .        {						\
    630 .          _s->prev = NULL;				\
    631 .          _abfd->sections = _s;			\
    632 .        }						\
    633 .      _abfd->section_last = _s;			\
    634 .    }							\
    635 .  while (0)
    636 .#define bfd_section_list_prepend(ABFD, S) \
    637 .  do							\
    638 .    {							\
    639 .      asection *_s = S;				\
    640 .      bfd *_abfd = ABFD;				\
    641 .      _s->prev = NULL;					\
    642 .      if (_abfd->sections)				\
    643 .        {						\
    644 .          _s->next = _abfd->sections;			\
    645 .          _abfd->sections->prev = _s;			\
    646 .        }						\
    647 .      else						\
    648 .        {						\
    649 .          _s->next = NULL;				\
    650 .          _abfd->section_last = _s;			\
    651 .        }						\
    652 .      _abfd->sections = _s;				\
    653 .    }							\
    654 .  while (0)
    655 .#define bfd_section_list_insert_after(ABFD, A, S) \
    656 .  do							\
    657 .    {							\
    658 .      asection *_a = A;				\
    659 .      asection *_s = S;				\
    660 .      asection *_next = _a->next;			\
    661 .      _s->next = _next;				\
    662 .      _s->prev = _a;					\
    663 .      _a->next = _s;					\
    664 .      if (_next)					\
    665 .        _next->prev = _s;				\
    666 .      else						\
    667 .        (ABFD)->section_last = _s;			\
    668 .    }							\
    669 .  while (0)
    670 .#define bfd_section_list_insert_before(ABFD, B, S) \
    671 .  do							\
    672 .    {							\
    673 .      asection *_b = B;				\
    674 .      asection *_s = S;				\
    675 .      asection *_prev = _b->prev;			\
    676 .      _s->prev = _prev;				\
    677 .      _s->next = _b;					\
    678 .      _b->prev = _s;					\
    679 .      if (_prev)					\
    680 .        _prev->next = _s;				\
    681 .      else						\
    682 .        (ABFD)->sections = _s;				\
    683 .    }							\
    684 .  while (0)
    685 .#define bfd_section_removed_from_list(ABFD, S) \
    686 .  ((S)->next == NULL ? (ABFD)->section_last != (S) : (S)->next->prev != (S))
    687 .
    688 .#define BFD_FAKE_SECTION(SEC, FLAGS, SYM, NAME, IDX)			\
    689 .  {* name, id,  index, next, prev, flags, user_set_vma,            *}	\
    690 .  { NAME,  IDX, 0,     NULL, NULL, FLAGS, 0,				\
    691 .									\
    692 .  {* linker_mark, linker_has_input, gc_mark, decompress_status,    *}	\
    693 .     0,           0,                1,       0,			\
    694 .									\
    695 .  {* segment_mark, sec_info_type, use_rela_p,                      *}	\
    696 .     0,            0,             0,					\
    697 .									\
    698 .  {* sec_flg0, sec_flg1, sec_flg2, sec_flg3, sec_flg4, sec_flg5,   *}	\
    699 .     0,        0,        0,        0,        0,        0,		\
    700 .									\
    701 .  {* vma, lma, size, rawsize, compressed_size, relax, relax_count, *}	\
    702 .     0,   0,   0,    0,       0,               0,     0,		\
    703 .									\
    704 .  {* output_offset, output_section, alignment_power,               *}	\
    705 .     0,             &SEC,           0,					\
    706 .									\
    707 .  {* relocation, orelocation, reloc_count, filepos, rel_filepos,   *}	\
    708 .     NULL,       NULL,        0,           0,       0,			\
    709 .									\
    710 .  {* line_filepos, userdata, contents, lineno, lineno_count,       *}	\
    711 .     0,            NULL,     NULL,     NULL,   0,			\
    712 .									\
    713 .  {* entsize, kept_section, moving_line_filepos,		     *}	\
    714 .     0,       NULL,	      0,					\
    715 .									\
    716 .  {* target_index, used_by_bfd, constructor_chain, owner,          *}	\
    717 .     0,            NULL,        NULL,              NULL,		\
    718 .									\
    719 .  {* symbol,                    symbol_ptr_ptr,                    *}	\
    720 .     (struct bfd_symbol *) SYM, &SEC.symbol,				\
    721 .									\
    722 .  {* map_head, map_tail                                            *}	\
    723 .     { NULL }, { NULL }						\
    724 .    }
    725 .
    726 */
    727 
    728 /* We use a macro to initialize the static asymbol structures because
    729    traditional C does not permit us to initialize a union member while
    730    gcc warns if we don't initialize it.  */
    731  /* the_bfd, name, value, attr, section [, udata] */
    732 #ifdef __STDC__
    733 #define GLOBAL_SYM_INIT(NAME, SECTION) \
    734   { 0, NAME, 0, BSF_SECTION_SYM, SECTION, { 0 }}
    735 #else
    736 #define GLOBAL_SYM_INIT(NAME, SECTION) \
    737   { 0, NAME, 0, BSF_SECTION_SYM, SECTION }
    738 #endif
    739 
    740 /* These symbols are global, not specific to any BFD.  Therefore, anything
    741    that tries to change them is broken, and should be repaired.  */
    742 
    743 static const asymbol global_syms[] =
    744 {
    745   GLOBAL_SYM_INIT (BFD_COM_SECTION_NAME, bfd_com_section_ptr),
    746   GLOBAL_SYM_INIT (BFD_UND_SECTION_NAME, bfd_und_section_ptr),
    747   GLOBAL_SYM_INIT (BFD_ABS_SECTION_NAME, bfd_abs_section_ptr),
    748   GLOBAL_SYM_INIT (BFD_IND_SECTION_NAME, bfd_ind_section_ptr)
    749 };
    750 
    751 #define STD_SECTION(NAME, IDX, FLAGS) \
    752   BFD_FAKE_SECTION(_bfd_std_section[IDX], FLAGS, &global_syms[IDX], NAME, IDX)
    753 
    754 asection _bfd_std_section[] = {
    755   STD_SECTION (BFD_COM_SECTION_NAME, 0, SEC_IS_COMMON),
    756   STD_SECTION (BFD_UND_SECTION_NAME, 1, 0),
    757   STD_SECTION (BFD_ABS_SECTION_NAME, 2, 0),
    758   STD_SECTION (BFD_IND_SECTION_NAME, 3, 0)
    759 };
    760 #undef STD_SECTION
    761 
    762 /* Initialize an entry in the section hash table.  */
    763 
    764 struct bfd_hash_entry *
    765 bfd_section_hash_newfunc (struct bfd_hash_entry *entry,
    766 			  struct bfd_hash_table *table,
    767 			  const char *string)
    768 {
    769   /* Allocate the structure if it has not already been allocated by a
    770      subclass.  */
    771   if (entry == NULL)
    772     {
    773       entry = (struct bfd_hash_entry *)
    774 	bfd_hash_allocate (table, sizeof (struct section_hash_entry));
    775       if (entry == NULL)
    776 	return entry;
    777     }
    778 
    779   /* Call the allocation method of the superclass.  */
    780   entry = bfd_hash_newfunc (entry, table, string);
    781   if (entry != NULL)
    782     memset (&((struct section_hash_entry *) entry)->section, 0,
    783 	    sizeof (asection));
    784 
    785   return entry;
    786 }
    787 
    788 #define section_hash_lookup(table, string, create, copy) \
    789   ((struct section_hash_entry *) \
    790    bfd_hash_lookup ((table), (string), (create), (copy)))
    791 
    792 /* Create a symbol whose only job is to point to this section.  This
    793    is useful for things like relocs which are relative to the base
    794    of a section.  */
    795 
    796 bfd_boolean
    797 _bfd_generic_new_section_hook (bfd *abfd, asection *newsect)
    798 {
    799   newsect->symbol = bfd_make_empty_symbol (abfd);
    800   if (newsect->symbol == NULL)
    801     return FALSE;
    802 
    803   newsect->symbol->name = newsect->name;
    804   newsect->symbol->value = 0;
    805   newsect->symbol->section = newsect;
    806   newsect->symbol->flags = BSF_SECTION_SYM;
    807 
    808   newsect->symbol_ptr_ptr = &newsect->symbol;
    809   return TRUE;
    810 }
    811 
    812 /* Initializes a new section.  NEWSECT->NAME is already set.  */
    813 
    814 static asection *
    815 bfd_section_init (bfd *abfd, asection *newsect)
    816 {
    817   static int section_id = 0x10;  /* id 0 to 3 used by STD_SECTION.  */
    818 
    819   newsect->id = section_id;
    820   newsect->index = abfd->section_count;
    821   newsect->owner = abfd;
    822 
    823   if (! BFD_SEND (abfd, _new_section_hook, (abfd, newsect)))
    824     return NULL;
    825 
    826   section_id++;
    827   abfd->section_count++;
    828   bfd_section_list_append (abfd, newsect);
    829   return newsect;
    830 }
    831 
    832 /*
    833 DOCDD
    834 INODE
    835 section prototypes,  , typedef asection, Sections
    836 SUBSECTION
    837 	Section prototypes
    838 
    839 These are the functions exported by the section handling part of BFD.
    840 */
    841 
    842 /*
    843 FUNCTION
    844 	bfd_section_list_clear
    845 
    846 SYNOPSIS
    847 	void bfd_section_list_clear (bfd *);
    848 
    849 DESCRIPTION
    850 	Clears the section list, and also resets the section count and
    851 	hash table entries.
    852 */
    853 
    854 void
    855 bfd_section_list_clear (bfd *abfd)
    856 {
    857   abfd->sections = NULL;
    858   abfd->section_last = NULL;
    859   abfd->section_count = 0;
    860   memset (abfd->section_htab.table, 0,
    861 	  abfd->section_htab.size * sizeof (struct bfd_hash_entry *));
    862   abfd->section_htab.count = 0;
    863 }
    864 
    865 /*
    866 FUNCTION
    867 	bfd_get_section_by_name
    868 
    869 SYNOPSIS
    870 	asection *bfd_get_section_by_name (bfd *abfd, const char *name);
    871 
    872 DESCRIPTION
    873 	Return the most recently created section attached to @var{abfd}
    874 	named @var{name}.  Return NULL if no such section exists.
    875 */
    876 
    877 asection *
    878 bfd_get_section_by_name (bfd *abfd, const char *name)
    879 {
    880   struct section_hash_entry *sh;
    881 
    882   sh = section_hash_lookup (&abfd->section_htab, name, FALSE, FALSE);
    883   if (sh != NULL)
    884     return &sh->section;
    885 
    886   return NULL;
    887 }
    888 
    889 /*
    890 FUNCTION
    891        bfd_get_next_section_by_name
    892 
    893 SYNOPSIS
    894        asection *bfd_get_next_section_by_name (asection *sec);
    895 
    896 DESCRIPTION
    897        Given @var{sec} is a section returned by @code{bfd_get_section_by_name},
    898        return the next most recently created section attached to the same
    899        BFD with the same name.  Return NULL if no such section exists.
    900 */
    901 
    902 asection *
    903 bfd_get_next_section_by_name (asection *sec)
    904 {
    905   struct section_hash_entry *sh;
    906   const char *name;
    907   unsigned long hash;
    908 
    909   sh = ((struct section_hash_entry *)
    910 	((char *) sec - offsetof (struct section_hash_entry, section)));
    911 
    912   hash = sh->root.hash;
    913   name = sec->name;
    914   for (sh = (struct section_hash_entry *) sh->root.next;
    915        sh != NULL;
    916        sh = (struct section_hash_entry *) sh->root.next)
    917     if (sh->root.hash == hash
    918        && strcmp (sh->root.string, name) == 0)
    919       return &sh->section;
    920 
    921   return NULL;
    922 }
    923 
    924 /*
    925 FUNCTION
    926 	bfd_get_linker_section
    927 
    928 SYNOPSIS
    929 	asection *bfd_get_linker_section (bfd *abfd, const char *name);
    930 
    931 DESCRIPTION
    932 	Return the linker created section attached to @var{abfd}
    933 	named @var{name}.  Return NULL if no such section exists.
    934 */
    935 
    936 asection *
    937 bfd_get_linker_section (bfd *abfd, const char *name)
    938 {
    939   asection *sec = bfd_get_section_by_name (abfd, name);
    940 
    941   while (sec != NULL && (sec->flags & SEC_LINKER_CREATED) == 0)
    942     sec = bfd_get_next_section_by_name (sec);
    943   return sec;
    944 }
    945 
    946 /*
    947 FUNCTION
    948 	bfd_get_section_by_name_if
    949 
    950 SYNOPSIS
    951 	asection *bfd_get_section_by_name_if
    952 	  (bfd *abfd,
    953 	   const char *name,
    954 	   bfd_boolean (*func) (bfd *abfd, asection *sect, void *obj),
    955 	   void *obj);
    956 
    957 DESCRIPTION
    958 	Call the provided function @var{func} for each section
    959 	attached to the BFD @var{abfd} whose name matches @var{name},
    960 	passing @var{obj} as an argument. The function will be called
    961 	as if by
    962 
    963 |	func (abfd, the_section, obj);
    964 
    965 	It returns the first section for which @var{func} returns true,
    966 	otherwise <<NULL>>.
    967 
    968 */
    969 
    970 asection *
    971 bfd_get_section_by_name_if (bfd *abfd, const char *name,
    972 			    bfd_boolean (*operation) (bfd *,
    973 						      asection *,
    974 						      void *),
    975 			    void *user_storage)
    976 {
    977   struct section_hash_entry *sh;
    978   unsigned long hash;
    979 
    980   sh = section_hash_lookup (&abfd->section_htab, name, FALSE, FALSE);
    981   if (sh == NULL)
    982     return NULL;
    983 
    984   hash = sh->root.hash;
    985   do
    986     {
    987       if ((*operation) (abfd, &sh->section, user_storage))
    988 	return &sh->section;
    989       sh = (struct section_hash_entry *) sh->root.next;
    990     }
    991   while (sh != NULL && sh->root.hash == hash
    992 	 && strcmp (sh->root.string, name) == 0);
    993 
    994   return NULL;
    995 }
    996 
    997 /*
    998 FUNCTION
    999 	bfd_get_unique_section_name
   1000 
   1001 SYNOPSIS
   1002 	char *bfd_get_unique_section_name
   1003 	  (bfd *abfd, const char *templat, int *count);
   1004 
   1005 DESCRIPTION
   1006 	Invent a section name that is unique in @var{abfd} by tacking
   1007 	a dot and a digit suffix onto the original @var{templat}.  If
   1008 	@var{count} is non-NULL, then it specifies the first number
   1009 	tried as a suffix to generate a unique name.  The value
   1010 	pointed to by @var{count} will be incremented in this case.
   1011 */
   1012 
   1013 char *
   1014 bfd_get_unique_section_name (bfd *abfd, const char *templat, int *count)
   1015 {
   1016   int num;
   1017   unsigned int len;
   1018   char *sname;
   1019 
   1020   len = strlen (templat);
   1021   sname = (char *) bfd_malloc (len + 8);
   1022   if (sname == NULL)
   1023     return NULL;
   1024   memcpy (sname, templat, len);
   1025   num = 1;
   1026   if (count != NULL)
   1027     num = *count;
   1028 
   1029   do
   1030     {
   1031       /* If we have a million sections, something is badly wrong.  */
   1032       if (num > 999999)
   1033 	abort ();
   1034       sprintf (sname + len, ".%d", num++);
   1035     }
   1036   while (section_hash_lookup (&abfd->section_htab, sname, FALSE, FALSE));
   1037 
   1038   if (count != NULL)
   1039     *count = num;
   1040   return sname;
   1041 }
   1042 
   1043 /*
   1044 FUNCTION
   1045 	bfd_make_section_old_way
   1046 
   1047 SYNOPSIS
   1048 	asection *bfd_make_section_old_way (bfd *abfd, const char *name);
   1049 
   1050 DESCRIPTION
   1051 	Create a new empty section called @var{name}
   1052 	and attach it to the end of the chain of sections for the
   1053 	BFD @var{abfd}. An attempt to create a section with a name which
   1054 	is already in use returns its pointer without changing the
   1055 	section chain.
   1056 
   1057 	It has the funny name since this is the way it used to be
   1058 	before it was rewritten....
   1059 
   1060 	Possible errors are:
   1061 	o <<bfd_error_invalid_operation>> -
   1062 	If output has already started for this BFD.
   1063 	o <<bfd_error_no_memory>> -
   1064 	If memory allocation fails.
   1065 
   1066 */
   1067 
   1068 asection *
   1069 bfd_make_section_old_way (bfd *abfd, const char *name)
   1070 {
   1071   asection *newsect;
   1072 
   1073   if (abfd->output_has_begun)
   1074     {
   1075       bfd_set_error (bfd_error_invalid_operation);
   1076       return NULL;
   1077     }
   1078 
   1079   if (strcmp (name, BFD_ABS_SECTION_NAME) == 0)
   1080     newsect = bfd_abs_section_ptr;
   1081   else if (strcmp (name, BFD_COM_SECTION_NAME) == 0)
   1082     newsect = bfd_com_section_ptr;
   1083   else if (strcmp (name, BFD_UND_SECTION_NAME) == 0)
   1084     newsect = bfd_und_section_ptr;
   1085   else if (strcmp (name, BFD_IND_SECTION_NAME) == 0)
   1086     newsect = bfd_ind_section_ptr;
   1087   else
   1088     {
   1089       struct section_hash_entry *sh;
   1090 
   1091       sh = section_hash_lookup (&abfd->section_htab, name, TRUE, FALSE);
   1092       if (sh == NULL)
   1093 	return NULL;
   1094 
   1095       newsect = &sh->section;
   1096       if (newsect->name != NULL)
   1097 	{
   1098 	  /* Section already exists.  */
   1099 	  return newsect;
   1100 	}
   1101 
   1102       newsect->name = name;
   1103       return bfd_section_init (abfd, newsect);
   1104     }
   1105 
   1106   /* Call new_section_hook when "creating" the standard abs, com, und
   1107      and ind sections to tack on format specific section data.
   1108      Also, create a proper section symbol.  */
   1109   if (! BFD_SEND (abfd, _new_section_hook, (abfd, newsect)))
   1110     return NULL;
   1111   return newsect;
   1112 }
   1113 
   1114 /*
   1115 FUNCTION
   1116 	bfd_make_section_anyway_with_flags
   1117 
   1118 SYNOPSIS
   1119 	asection *bfd_make_section_anyway_with_flags
   1120 	  (bfd *abfd, const char *name, flagword flags);
   1121 
   1122 DESCRIPTION
   1123    Create a new empty section called @var{name} and attach it to the end of
   1124    the chain of sections for @var{abfd}.  Create a new section even if there
   1125    is already a section with that name.  Also set the attributes of the
   1126    new section to the value @var{flags}.
   1127 
   1128    Return <<NULL>> and set <<bfd_error>> on error; possible errors are:
   1129    o <<bfd_error_invalid_operation>> - If output has already started for @var{abfd}.
   1130    o <<bfd_error_no_memory>> - If memory allocation fails.
   1131 */
   1132 
   1133 sec_ptr
   1134 bfd_make_section_anyway_with_flags (bfd *abfd, const char *name,
   1135 				    flagword flags)
   1136 {
   1137   struct section_hash_entry *sh;
   1138   asection *newsect;
   1139 
   1140   if (abfd->output_has_begun)
   1141     {
   1142       bfd_set_error (bfd_error_invalid_operation);
   1143       return NULL;
   1144     }
   1145 
   1146   sh = section_hash_lookup (&abfd->section_htab, name, TRUE, FALSE);
   1147   if (sh == NULL)
   1148     return NULL;
   1149 
   1150   newsect = &sh->section;
   1151   if (newsect->name != NULL)
   1152     {
   1153       /* We are making a section of the same name.  Put it in the
   1154 	 section hash table.  Even though we can't find it directly by a
   1155 	 hash lookup, we'll be able to find the section by traversing
   1156 	 sh->root.next quicker than looking at all the bfd sections.  */
   1157       struct section_hash_entry *new_sh;
   1158       new_sh = (struct section_hash_entry *)
   1159 	bfd_section_hash_newfunc (NULL, &abfd->section_htab, name);
   1160       if (new_sh == NULL)
   1161 	return NULL;
   1162 
   1163       new_sh->root = sh->root;
   1164       sh->root.next = &new_sh->root;
   1165       newsect = &new_sh->section;
   1166     }
   1167 
   1168   newsect->flags = flags;
   1169   newsect->name = name;
   1170   return bfd_section_init (abfd, newsect);
   1171 }
   1172 
   1173 /*
   1174 FUNCTION
   1175 	bfd_make_section_anyway
   1176 
   1177 SYNOPSIS
   1178 	asection *bfd_make_section_anyway (bfd *abfd, const char *name);
   1179 
   1180 DESCRIPTION
   1181    Create a new empty section called @var{name} and attach it to the end of
   1182    the chain of sections for @var{abfd}.  Create a new section even if there
   1183    is already a section with that name.
   1184 
   1185    Return <<NULL>> and set <<bfd_error>> on error; possible errors are:
   1186    o <<bfd_error_invalid_operation>> - If output has already started for @var{abfd}.
   1187    o <<bfd_error_no_memory>> - If memory allocation fails.
   1188 */
   1189 
   1190 sec_ptr
   1191 bfd_make_section_anyway (bfd *abfd, const char *name)
   1192 {
   1193   return bfd_make_section_anyway_with_flags (abfd, name, 0);
   1194 }
   1195 
   1196 /*
   1197 FUNCTION
   1198 	bfd_make_section_with_flags
   1199 
   1200 SYNOPSIS
   1201 	asection *bfd_make_section_with_flags
   1202 	  (bfd *, const char *name, flagword flags);
   1203 
   1204 DESCRIPTION
   1205    Like <<bfd_make_section_anyway>>, but return <<NULL>> (without calling
   1206    bfd_set_error ()) without changing the section chain if there is already a
   1207    section named @var{name}.  Also set the attributes of the new section to
   1208    the value @var{flags}.  If there is an error, return <<NULL>> and set
   1209    <<bfd_error>>.
   1210 */
   1211 
   1212 asection *
   1213 bfd_make_section_with_flags (bfd *abfd, const char *name,
   1214 			     flagword flags)
   1215 {
   1216   struct section_hash_entry *sh;
   1217   asection *newsect;
   1218 
   1219   if (abfd->output_has_begun)
   1220     {
   1221       bfd_set_error (bfd_error_invalid_operation);
   1222       return NULL;
   1223     }
   1224 
   1225   if (strcmp (name, BFD_ABS_SECTION_NAME) == 0
   1226       || strcmp (name, BFD_COM_SECTION_NAME) == 0
   1227       || strcmp (name, BFD_UND_SECTION_NAME) == 0
   1228       || strcmp (name, BFD_IND_SECTION_NAME) == 0)
   1229     return NULL;
   1230 
   1231   sh = section_hash_lookup (&abfd->section_htab, name, TRUE, FALSE);
   1232   if (sh == NULL)
   1233     return NULL;
   1234 
   1235   newsect = &sh->section;
   1236   if (newsect->name != NULL)
   1237     {
   1238       /* Section already exists.  */
   1239       return NULL;
   1240     }
   1241 
   1242   newsect->name = name;
   1243   newsect->flags = flags;
   1244   return bfd_section_init (abfd, newsect);
   1245 }
   1246 
   1247 /*
   1248 FUNCTION
   1249 	bfd_make_section
   1250 
   1251 SYNOPSIS
   1252 	asection *bfd_make_section (bfd *, const char *name);
   1253 
   1254 DESCRIPTION
   1255    Like <<bfd_make_section_anyway>>, but return <<NULL>> (without calling
   1256    bfd_set_error ()) without changing the section chain if there is already a
   1257    section named @var{name}.  If there is an error, return <<NULL>> and set
   1258    <<bfd_error>>.
   1259 */
   1260 
   1261 asection *
   1262 bfd_make_section (bfd *abfd, const char *name)
   1263 {
   1264   return bfd_make_section_with_flags (abfd, name, 0);
   1265 }
   1266 
   1267 /*
   1268 FUNCTION
   1269 	bfd_set_section_flags
   1270 
   1271 SYNOPSIS
   1272 	bfd_boolean bfd_set_section_flags
   1273 	  (bfd *abfd, asection *sec, flagword flags);
   1274 
   1275 DESCRIPTION
   1276 	Set the attributes of the section @var{sec} in the BFD
   1277 	@var{abfd} to the value @var{flags}. Return <<TRUE>> on success,
   1278 	<<FALSE>> on error. Possible error returns are:
   1279 
   1280 	o <<bfd_error_invalid_operation>> -
   1281 	The section cannot have one or more of the attributes
   1282 	requested. For example, a .bss section in <<a.out>> may not
   1283 	have the <<SEC_HAS_CONTENTS>> field set.
   1284 
   1285 */
   1286 
   1287 bfd_boolean
   1288 bfd_set_section_flags (bfd *abfd ATTRIBUTE_UNUSED,
   1289 		       sec_ptr section,
   1290 		       flagword flags)
   1291 {
   1292   section->flags = flags;
   1293   return TRUE;
   1294 }
   1295 
   1296 /*
   1297 FUNCTION
   1298 	bfd_rename_section
   1299 
   1300 SYNOPSIS
   1301 	void bfd_rename_section
   1302 	  (bfd *abfd, asection *sec, const char *newname);
   1303 
   1304 DESCRIPTION
   1305 	Rename section @var{sec} in @var{abfd} to @var{newname}.
   1306 */
   1307 
   1308 void
   1309 bfd_rename_section (bfd *abfd, sec_ptr sec, const char *newname)
   1310 {
   1311   struct section_hash_entry *sh;
   1312 
   1313   sh = (struct section_hash_entry *)
   1314     ((char *) sec - offsetof (struct section_hash_entry, section));
   1315   sh->section.name = newname;
   1316   bfd_hash_rename (&abfd->section_htab, newname, &sh->root);
   1317 }
   1318 
   1319 /*
   1320 FUNCTION
   1321 	bfd_map_over_sections
   1322 
   1323 SYNOPSIS
   1324 	void bfd_map_over_sections
   1325 	  (bfd *abfd,
   1326 	   void (*func) (bfd *abfd, asection *sect, void *obj),
   1327 	   void *obj);
   1328 
   1329 DESCRIPTION
   1330 	Call the provided function @var{func} for each section
   1331 	attached to the BFD @var{abfd}, passing @var{obj} as an
   1332 	argument. The function will be called as if by
   1333 
   1334 |	func (abfd, the_section, obj);
   1335 
   1336 	This is the preferred method for iterating over sections; an
   1337 	alternative would be to use a loop:
   1338 
   1339 |	   asection *p;
   1340 |	   for (p = abfd->sections; p != NULL; p = p->next)
   1341 |	      func (abfd, p, ...)
   1342 
   1343 */
   1344 
   1345 void
   1346 bfd_map_over_sections (bfd *abfd,
   1347 		       void (*operation) (bfd *, asection *, void *),
   1348 		       void *user_storage)
   1349 {
   1350   asection *sect;
   1351   unsigned int i = 0;
   1352 
   1353   for (sect = abfd->sections; sect != NULL; i++, sect = sect->next)
   1354     (*operation) (abfd, sect, user_storage);
   1355 
   1356   if (i != abfd->section_count)	/* Debugging */
   1357     abort ();
   1358 }
   1359 
   1360 /*
   1361 FUNCTION
   1362 	bfd_sections_find_if
   1363 
   1364 SYNOPSIS
   1365 	asection *bfd_sections_find_if
   1366 	  (bfd *abfd,
   1367 	   bfd_boolean (*operation) (bfd *abfd, asection *sect, void *obj),
   1368 	   void *obj);
   1369 
   1370 DESCRIPTION
   1371 	Call the provided function @var{operation} for each section
   1372 	attached to the BFD @var{abfd}, passing @var{obj} as an
   1373 	argument. The function will be called as if by
   1374 
   1375 |	operation (abfd, the_section, obj);
   1376 
   1377 	It returns the first section for which @var{operation} returns true.
   1378 
   1379 */
   1380 
   1381 asection *
   1382 bfd_sections_find_if (bfd *abfd,
   1383 		      bfd_boolean (*operation) (bfd *, asection *, void *),
   1384 		      void *user_storage)
   1385 {
   1386   asection *sect;
   1387 
   1388   for (sect = abfd->sections; sect != NULL; sect = sect->next)
   1389     if ((*operation) (abfd, sect, user_storage))
   1390       break;
   1391 
   1392   return sect;
   1393 }
   1394 
   1395 /*
   1396 FUNCTION
   1397 	bfd_set_section_size
   1398 
   1399 SYNOPSIS
   1400 	bfd_boolean bfd_set_section_size
   1401 	  (bfd *abfd, asection *sec, bfd_size_type val);
   1402 
   1403 DESCRIPTION
   1404 	Set @var{sec} to the size @var{val}. If the operation is
   1405 	ok, then <<TRUE>> is returned, else <<FALSE>>.
   1406 
   1407 	Possible error returns:
   1408 	o <<bfd_error_invalid_operation>> -
   1409 	Writing has started to the BFD, so setting the size is invalid.
   1410 
   1411 */
   1412 
   1413 bfd_boolean
   1414 bfd_set_section_size (bfd *abfd, sec_ptr ptr, bfd_size_type val)
   1415 {
   1416   /* Once you've started writing to any section you cannot create or change
   1417      the size of any others.  */
   1418 
   1419   if (abfd->output_has_begun)
   1420     {
   1421       bfd_set_error (bfd_error_invalid_operation);
   1422       return FALSE;
   1423     }
   1424 
   1425   ptr->size = val;
   1426   return TRUE;
   1427 }
   1428 
   1429 /*
   1430 FUNCTION
   1431 	bfd_set_section_contents
   1432 
   1433 SYNOPSIS
   1434 	bfd_boolean bfd_set_section_contents
   1435 	  (bfd *abfd, asection *section, const void *data,
   1436 	   file_ptr offset, bfd_size_type count);
   1437 
   1438 DESCRIPTION
   1439 	Sets the contents of the section @var{section} in BFD
   1440 	@var{abfd} to the data starting in memory at @var{data}. The
   1441 	data is written to the output section starting at offset
   1442 	@var{offset} for @var{count} octets.
   1443 
   1444 	Normally <<TRUE>> is returned, else <<FALSE>>. Possible error
   1445 	returns are:
   1446 	o <<bfd_error_no_contents>> -
   1447 	The output section does not have the <<SEC_HAS_CONTENTS>>
   1448 	attribute, so nothing can be written to it.
   1449 	o and some more too
   1450 
   1451 	This routine is front end to the back end function
   1452 	<<_bfd_set_section_contents>>.
   1453 
   1454 */
   1455 
   1456 bfd_boolean
   1457 bfd_set_section_contents (bfd *abfd,
   1458 			  sec_ptr section,
   1459 			  const void *location,
   1460 			  file_ptr offset,
   1461 			  bfd_size_type count)
   1462 {
   1463   bfd_size_type sz;
   1464 
   1465   if (!(bfd_get_section_flags (abfd, section) & SEC_HAS_CONTENTS))
   1466     {
   1467       bfd_set_error (bfd_error_no_contents);
   1468       return FALSE;
   1469     }
   1470 
   1471   sz = section->size;
   1472   if ((bfd_size_type) offset > sz
   1473       || count > sz
   1474       || offset + count > sz
   1475       || count != (size_t) count)
   1476     {
   1477       bfd_set_error (bfd_error_bad_value);
   1478       return FALSE;
   1479     }
   1480 
   1481   if (!bfd_write_p (abfd))
   1482     {
   1483       bfd_set_error (bfd_error_invalid_operation);
   1484       return FALSE;
   1485     }
   1486 
   1487   /* Record a copy of the data in memory if desired.  */
   1488   if (section->contents
   1489       && location != section->contents + offset)
   1490     memcpy (section->contents + offset, location, (size_t) count);
   1491 
   1492   if (BFD_SEND (abfd, _bfd_set_section_contents,
   1493 		(abfd, section, location, offset, count)))
   1494     {
   1495       abfd->output_has_begun = TRUE;
   1496       return TRUE;
   1497     }
   1498 
   1499   return FALSE;
   1500 }
   1501 
   1502 /*
   1503 FUNCTION
   1504 	bfd_get_section_contents
   1505 
   1506 SYNOPSIS
   1507 	bfd_boolean bfd_get_section_contents
   1508 	  (bfd *abfd, asection *section, void *location, file_ptr offset,
   1509 	   bfd_size_type count);
   1510 
   1511 DESCRIPTION
   1512 	Read data from @var{section} in BFD @var{abfd}
   1513 	into memory starting at @var{location}. The data is read at an
   1514 	offset of @var{offset} from the start of the input section,
   1515 	and is read for @var{count} bytes.
   1516 
   1517 	If the contents of a constructor with the <<SEC_CONSTRUCTOR>>
   1518 	flag set are requested or if the section does not have the
   1519 	<<SEC_HAS_CONTENTS>> flag set, then the @var{location} is filled
   1520 	with zeroes. If no errors occur, <<TRUE>> is returned, else
   1521 	<<FALSE>>.
   1522 
   1523 */
   1524 bfd_boolean
   1525 bfd_get_section_contents (bfd *abfd,
   1526 			  sec_ptr section,
   1527 			  void *location,
   1528 			  file_ptr offset,
   1529 			  bfd_size_type count)
   1530 {
   1531   bfd_size_type sz;
   1532 
   1533   if (section->flags & SEC_CONSTRUCTOR)
   1534     {
   1535       memset (location, 0, (size_t) count);
   1536       return TRUE;
   1537     }
   1538 
   1539   if (abfd->direction != write_direction && section->rawsize != 0)
   1540     sz = section->rawsize;
   1541   else
   1542     sz = section->size;
   1543   if ((bfd_size_type) offset > sz
   1544       || count > sz
   1545       || offset + count > sz
   1546       || count != (size_t) count)
   1547     {
   1548       bfd_set_error (bfd_error_bad_value);
   1549       return FALSE;
   1550     }
   1551 
   1552   if (count == 0)
   1553     /* Don't bother.  */
   1554     return TRUE;
   1555 
   1556   if ((section->flags & SEC_HAS_CONTENTS) == 0)
   1557     {
   1558       memset (location, 0, (size_t) count);
   1559       return TRUE;
   1560     }
   1561 
   1562   if ((section->flags & SEC_IN_MEMORY) != 0)
   1563     {
   1564       if (section->contents == NULL)
   1565 	{
   1566 	  /* This can happen because of errors earlier on in the linking process.
   1567 	     We do not want to seg-fault here, so clear the flag and return an
   1568 	     error code.  */
   1569 	  section->flags &= ~ SEC_IN_MEMORY;
   1570 	  bfd_set_error (bfd_error_invalid_operation);
   1571 	  return FALSE;
   1572 	}
   1573 
   1574       memmove (location, section->contents + offset, (size_t) count);
   1575       return TRUE;
   1576     }
   1577 
   1578   return BFD_SEND (abfd, _bfd_get_section_contents,
   1579 		   (abfd, section, location, offset, count));
   1580 }
   1581 
   1582 /*
   1583 FUNCTION
   1584 	bfd_malloc_and_get_section
   1585 
   1586 SYNOPSIS
   1587 	bfd_boolean bfd_malloc_and_get_section
   1588 	  (bfd *abfd, asection *section, bfd_byte **buf);
   1589 
   1590 DESCRIPTION
   1591 	Read all data from @var{section} in BFD @var{abfd}
   1592 	into a buffer, *@var{buf}, malloc'd by this function.
   1593 */
   1594 
   1595 bfd_boolean
   1596 bfd_malloc_and_get_section (bfd *abfd, sec_ptr sec, bfd_byte **buf)
   1597 {
   1598   *buf = NULL;
   1599   return bfd_get_full_section_contents (abfd, sec, buf);
   1600 }
   1601 /*
   1602 FUNCTION
   1603 	bfd_copy_private_section_data
   1604 
   1605 SYNOPSIS
   1606 	bfd_boolean bfd_copy_private_section_data
   1607 	  (bfd *ibfd, asection *isec, bfd *obfd, asection *osec);
   1608 
   1609 DESCRIPTION
   1610 	Copy private section information from @var{isec} in the BFD
   1611 	@var{ibfd} to the section @var{osec} in the BFD @var{obfd}.
   1612 	Return <<TRUE>> on success, <<FALSE>> on error.  Possible error
   1613 	returns are:
   1614 
   1615 	o <<bfd_error_no_memory>> -
   1616 	Not enough memory exists to create private data for @var{osec}.
   1617 
   1618 .#define bfd_copy_private_section_data(ibfd, isection, obfd, osection) \
   1619 .     BFD_SEND (obfd, _bfd_copy_private_section_data, \
   1620 .		(ibfd, isection, obfd, osection))
   1621 */
   1622 
   1623 /*
   1624 FUNCTION
   1625 	bfd_generic_is_group_section
   1626 
   1627 SYNOPSIS
   1628 	bfd_boolean bfd_generic_is_group_section (bfd *, const asection *sec);
   1629 
   1630 DESCRIPTION
   1631 	Returns TRUE if @var{sec} is a member of a group.
   1632 */
   1633 
   1634 bfd_boolean
   1635 bfd_generic_is_group_section (bfd *abfd ATTRIBUTE_UNUSED,
   1636 			      const asection *sec ATTRIBUTE_UNUSED)
   1637 {
   1638   return FALSE;
   1639 }
   1640 
   1641 /*
   1642 FUNCTION
   1643 	bfd_generic_discard_group
   1644 
   1645 SYNOPSIS
   1646 	bfd_boolean bfd_generic_discard_group (bfd *abfd, asection *group);
   1647 
   1648 DESCRIPTION
   1649 	Remove all members of @var{group} from the output.
   1650 */
   1651 
   1652 bfd_boolean
   1653 bfd_generic_discard_group (bfd *abfd ATTRIBUTE_UNUSED,
   1654 			   asection *group ATTRIBUTE_UNUSED)
   1655 {
   1656   return TRUE;
   1657 }
   1658