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+/* Object file "section" support for the BFD library.
+ Copyright (C) 1990, 91, 92, 93, 94, 95, 96, 1997
+ Free Software Foundation, Inc.
+ Written by Cygnus Support.
+
+This file is part of BFD, the Binary File Descriptor library.
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+/*
+SECTION
+ Sections
+
+ The raw data contained within a BFD is maintained through the
+ section abstraction. A single BFD may have any number of
+ sections. It keeps hold of them by pointing to the first;
+ each one points to the next in the list.
+
+ Sections are supported in BFD in <<section.c>>.
+
+@menu
+@* Section Input::
+@* Section Output::
+@* typedef asection::
+@* section prototypes::
+@end menu
+
+INODE
+Section Input, Section Output, Sections, Sections
+SUBSECTION
+ Section input
+
+ When a BFD is opened for reading, the section structures are
+ created and attached to the BFD.
+
+ Each section has a name which describes the section in the
+ outside world---for example, <<a.out>> would contain at least
+ three sections, called <<.text>>, <<.data>> and <<.bss>>.
+
+ Names need not be unique; for example a COFF file may have several
+ sections named <<.data>>.
+
+ Sometimes a BFD will contain more than the ``natural'' number of
+ sections. A back end may attach other sections containing
+ constructor data, or an application may add a section (using
+ <<bfd_make_section>>) to the sections attached to an already open
+ BFD. For example, the linker creates an extra section
+ <<COMMON>> for each input file's BFD to hold information about
+ common storage.
+
+ The raw data is not necessarily read in when
+ the section descriptor is created. Some targets may leave the
+ data in place until a <<bfd_get_section_contents>> call is
+ made. Other back ends may read in all the data at once. For
+ example, an S-record file has to be read once to determine the
+ size of the data. An IEEE-695 file doesn't contain raw data in
+ sections, but data and relocation expressions intermixed, so
+ the data area has to be parsed to get out the data and
+ relocations.
+
+INODE
+Section Output, typedef asection, Section Input, Sections
+
+SUBSECTION
+ Section output
+
+ To write a new object style BFD, the various sections to be
+ written have to be created. They are attached to the BFD in
+ the same way as input sections; data is written to the
+ sections using <<bfd_set_section_contents>>.
+
+ Any program that creates or combines sections (e.g., the assembler
+ and linker) must use the <<asection>> fields <<output_section>> and
+ <<output_offset>> to indicate the file sections to which each
+ section must be written. (If the section is being created from
+ scratch, <<output_section>> should probably point to the section
+ itself and <<output_offset>> should probably be zero.)
+
+ The data to be written comes from input sections attached
+ (via <<output_section>> pointers) to
+ the output sections. The output section structure can be
+ considered a filter for the input section: the output section
+ determines the vma of the output data and the name, but the
+ input section determines the offset into the output section of
+ the data to be written.
+
+ E.g., to create a section "O", starting at 0x100, 0x123 long,
+ containing two subsections, "A" at offset 0x0 (i.e., at vma
+ 0x100) and "B" at offset 0x20 (i.e., at vma 0x120) the <<asection>>
+ structures would look like:
+
+| section name "A"
+| output_offset 0x00
+| size 0x20
+| output_section -----------> section name "O"
+| | vma 0x100
+| section name "B" | size 0x123
+| output_offset 0x20 |
+| size 0x103 |
+| output_section --------|
+
+
+SUBSECTION
+ Link orders
+
+ The data within a section is stored in a @dfn{link_order}.
+ These are much like the fixups in <<gas>>. The link_order
+ abstraction allows a section to grow and shrink within itself.
+
+ A link_order knows how big it is, and which is the next
+ link_order and where the raw data for it is; it also points to
+ a list of relocations which apply to it.
+
+ The link_order is used by the linker to perform relaxing on
+ final code. The compiler creates code which is as big as
+ necessary to make it work without relaxing, and the user can
+ select whether to relax. Sometimes relaxing takes a lot of
+ time. The linker runs around the relocations to see if any
+ are attached to data which can be shrunk, if so it does it on
+ a link_order by link_order basis.
+
+*/
+
+
+#include "bfd.h"
+#include "sysdep.h"
+#include "libbfd.h"
+#include "bfdlink.h"
+
+/*
+DOCDD
+INODE
+typedef asection, section prototypes, Section Output, Sections
+SUBSECTION
+ typedef asection
+
+ Here is the section structure:
+
+CODE_FRAGMENT
+.
+.typedef struct sec
+.{
+. {* The name of the section; the name isn't a copy, the pointer is
+. the same as that passed to bfd_make_section. *}
+.
+. CONST char *name;
+.
+. {* Which section is it; 0..nth. *}
+.
+. int index;
+.
+. {* The next section in the list belonging to the BFD, or NULL. *}
+.
+. struct sec *next;
+.
+. {* The field flags contains attributes of the section. Some
+. flags are read in from the object file, and some are
+. synthesized from other information. *}
+.
+. flagword flags;
+.
+.#define SEC_NO_FLAGS 0x000
+.
+. {* Tells the OS to allocate space for this section when loading.
+. This is clear for a section containing debug information
+. only. *}
+.#define SEC_ALLOC 0x001
+.
+. {* Tells the OS to load the section from the file when loading.
+. This is clear for a .bss section. *}
+.#define SEC_LOAD 0x002
+.
+. {* The section contains data still to be relocated, so there is
+. some relocation information too. *}
+.#define SEC_RELOC 0x004
+.
+.#if 0 {* Obsolete ? *}
+.#define SEC_BALIGN 0x008
+.#endif
+.
+. {* A signal to the OS that the section contains read only
+. data. *}
+.#define SEC_READONLY 0x010
+.
+. {* The section contains code only. *}
+.#define SEC_CODE 0x020
+.
+. {* The section contains data only. *}
+.#define SEC_DATA 0x040
+.
+. {* The section will reside in ROM. *}
+.#define SEC_ROM 0x080
+.
+. {* The section contains constructor information. This section
+. type is used by the linker to create lists of constructors and
+. destructors used by <<g++>>. When a back end sees a symbol
+. which should be used in a constructor list, it creates a new
+. section for the type of name (e.g., <<__CTOR_LIST__>>), attaches
+. the symbol to it, and builds a relocation. To build the lists
+. of constructors, all the linker has to do is catenate all the
+. sections called <<__CTOR_LIST__>> and relocate the data
+. contained within - exactly the operations it would peform on
+. standard data. *}
+.#define SEC_CONSTRUCTOR 0x100
+.
+. {* The section is a constructor, and should be placed at the
+. end of the text, data, or bss section(?). *}
+.#define SEC_CONSTRUCTOR_TEXT 0x1100
+.#define SEC_CONSTRUCTOR_DATA 0x2100
+.#define SEC_CONSTRUCTOR_BSS 0x3100
+.
+. {* The section has contents - a data section could be
+. <<SEC_ALLOC>> | <<SEC_HAS_CONTENTS>>; a debug section could be
+. <<SEC_HAS_CONTENTS>> *}
+.#define SEC_HAS_CONTENTS 0x200
+.
+. {* An instruction to the linker to not output the section
+. even if it has information which would normally be written. *}
+.#define SEC_NEVER_LOAD 0x400
+.
+. {* The section is a COFF shared library section. This flag is
+. only for the linker. If this type of section appears in
+. the input file, the linker must copy it to the output file
+. without changing the vma or size. FIXME: Although this
+. was originally intended to be general, it really is COFF
+. specific (and the flag was renamed to indicate this). It
+. might be cleaner to have some more general mechanism to
+. allow the back end to control what the linker does with
+. sections. *}
+.#define SEC_COFF_SHARED_LIBRARY 0x800
+.
+. {* The section contains common symbols (symbols may be defined
+. multiple times, the value of a symbol is the amount of
+. space it requires, and the largest symbol value is the one
+. used). Most targets have exactly one of these (which we
+. translate to bfd_com_section_ptr), but ECOFF has two. *}
+.#define SEC_IS_COMMON 0x8000
+.
+. {* The section contains only debugging information. For
+. example, this is set for ELF .debug and .stab sections.
+. strip tests this flag to see if a section can be
+. discarded. *}
+.#define SEC_DEBUGGING 0x10000
+.
+. {* The contents of this section are held in memory pointed to
+. by the contents field. This is checked by
+. bfd_get_section_contents, and the data is retrieved from
+. memory if appropriate. *}
+.#define SEC_IN_MEMORY 0x20000
+.
+. {* The contents of this section are to be excluded by the
+. linker for executable and shared objects unless those
+. objects are to be further relocated. *}
+.#define SEC_EXCLUDE 0x40000
+.
+. {* The contents of this section are to be sorted by the
+. based on the address specified in the associated symbol
+. table. *}
+.#define SEC_SORT_ENTRIES 0x80000
+.
+. {* When linking, duplicate sections of the same name should be
+. discarded, rather than being combined into a single section as
+. is usually done. This is similar to how common symbols are
+. handled. See SEC_LINK_DUPLICATES below. *}
+.#define SEC_LINK_ONCE 0x100000
+.
+. {* If SEC_LINK_ONCE is set, this bitfield describes how the linker
+. should handle duplicate sections. *}
+.#define SEC_LINK_DUPLICATES 0x600000
+.
+. {* This value for SEC_LINK_DUPLICATES means that duplicate
+. sections with the same name should simply be discarded. *}
+.#define SEC_LINK_DUPLICATES_DISCARD 0x0
+.
+. {* This value for SEC_LINK_DUPLICATES means that the linker
+. should warn if there are any duplicate sections, although
+. it should still only link one copy. *}
+.#define SEC_LINK_DUPLICATES_ONE_ONLY 0x200000
+.
+. {* This value for SEC_LINK_DUPLICATES means that the linker
+. should warn if any duplicate sections are a different size. *}
+.#define SEC_LINK_DUPLICATES_SAME_SIZE 0x400000
+.
+. {* This value for SEC_LINK_DUPLICATES means that the linker
+. should warn if any duplicate sections contain different
+. contents. *}
+.#define SEC_LINK_DUPLICATES_SAME_CONTENTS 0x600000
+.
+. {* This section was created by the linker as part of dynamic
+. relocation or other arcane processing. It is skipped when
+. going through the first-pass output, trusting that someone
+. else up the line will take care of it later. *}
+.#define SEC_LINKER_CREATED 0x800000
+.
+. {* This section should not be subject to garbage collection. *}
+.#define SEC_KEEP 0x1000000
+.
+. {* End of section flags. *}
+.
+. {* Some internal packed boolean fields. *}
+.
+. {* See the vma field. *}
+. unsigned int user_set_vma : 1;
+.
+. {* Whether relocations have been processed. *}
+. unsigned int reloc_done : 1;
+.
+. {* A mark flag used by some of the linker backends. *}
+. unsigned int linker_mark : 1;
+.
+. {* A mark flag used by some linker backends for garbage collection. *}
+. unsigned int gc_mark : 1;
+.
+. {* End of internal packed boolean fields. *}
+.
+. {* The virtual memory address of the section - where it will be
+. at run time. The symbols are relocated against this. The
+. user_set_vma flag is maintained by bfd; if it's not set, the
+. backend can assign addresses (for example, in <<a.out>>, where
+. the default address for <<.data>> is dependent on the specific
+. target and various flags). *}
+.
+. bfd_vma vma;
+.
+. {* The load address of the section - where it would be in a
+. rom image; really only used for writing section header
+. information. *}
+.
+. bfd_vma lma;
+.
+. {* The size of the section in bytes, as it will be output.
+. contains a value even if the section has no contents (e.g., the
+. size of <<.bss>>). This will be filled in after relocation *}
+.
+. bfd_size_type _cooked_size;
+.
+. {* The original size on disk of the section, in bytes. Normally this
+. value is the same as the size, but if some relaxing has
+. been done, then this value will be bigger. *}
+.
+. bfd_size_type _raw_size;
+.
+. {* If this section is going to be output, then this value is the
+. offset into the output section of the first byte in the input
+. section. E.g., if this was going to start at the 100th byte in
+. the output section, this value would be 100. *}
+.
+. bfd_vma output_offset;
+.
+. {* The output section through which to map on output. *}
+.
+. struct sec *output_section;
+.
+. {* The alignment requirement of the section, as an exponent of 2 -
+. e.g., 3 aligns to 2^3 (or 8). *}
+.
+. unsigned int alignment_power;
+.
+. {* If an input section, a pointer to a vector of relocation
+. records for the data in this section. *}
+.
+. struct reloc_cache_entry *relocation;
+.
+. {* If an output section, a pointer to a vector of pointers to
+. relocation records for the data in this section. *}
+.
+. struct reloc_cache_entry **orelocation;
+.
+. {* The number of relocation records in one of the above *}
+.
+. unsigned reloc_count;
+.
+. {* Information below is back end specific - and not always used
+. or updated. *}
+.
+. {* File position of section data *}
+.
+. file_ptr filepos;
+.
+. {* File position of relocation info *}
+.
+. file_ptr rel_filepos;
+.
+. {* File position of line data *}
+.
+. file_ptr line_filepos;
+.
+. {* Pointer to data for applications *}
+.
+. PTR userdata;
+.
+. {* If the SEC_IN_MEMORY flag is set, this points to the actual
+. contents. *}
+. unsigned char *contents;
+.
+. {* Attached line number information *}
+.
+. alent *lineno;
+.
+. {* Number of line number records *}
+.
+. unsigned int lineno_count;
+.
+. {* When a section is being output, this value changes as more
+. linenumbers are written out *}
+.
+. file_ptr moving_line_filepos;
+.
+. {* What the section number is in the target world *}
+.
+. int target_index;
+.
+. PTR used_by_bfd;
+.
+. {* If this is a constructor section then here is a list of the
+. relocations created to relocate items within it. *}
+.
+. struct relent_chain *constructor_chain;
+.
+. {* The BFD which owns the section. *}
+.
+. bfd *owner;
+.
+. {* A symbol which points at this section only *}
+. struct symbol_cache_entry *symbol;
+. struct symbol_cache_entry **symbol_ptr_ptr;
+.
+. struct bfd_link_order *link_order_head;
+. struct bfd_link_order *link_order_tail;
+.} asection ;
+.
+. {* These sections are global, and are managed by BFD. The application
+. and target back end are not permitted to change the values in
+. these sections. New code should use the section_ptr macros rather
+. than referring directly to the const sections. The const sections
+. may eventually vanish. *}
+.#define BFD_ABS_SECTION_NAME "*ABS*"
+.#define BFD_UND_SECTION_NAME "*UND*"
+.#define BFD_COM_SECTION_NAME "*COM*"
+.#define BFD_IND_SECTION_NAME "*IND*"
+.
+. {* the absolute section *}
+.extern const asection bfd_abs_section;
+.#define bfd_abs_section_ptr ((asection *) &bfd_abs_section)
+.#define bfd_is_abs_section(sec) ((sec) == bfd_abs_section_ptr)
+. {* Pointer to the undefined section *}
+.extern const asection bfd_und_section;
+.#define bfd_und_section_ptr ((asection *) &bfd_und_section)
+.#define bfd_is_und_section(sec) ((sec) == bfd_und_section_ptr)
+. {* Pointer to the common section *}
+.extern const asection bfd_com_section;
+.#define bfd_com_section_ptr ((asection *) &bfd_com_section)
+. {* Pointer to the indirect section *}
+.extern const asection bfd_ind_section;
+.#define bfd_ind_section_ptr ((asection *) &bfd_ind_section)
+.#define bfd_is_ind_section(sec) ((sec) == bfd_ind_section_ptr)
+.
+.extern const struct symbol_cache_entry * const bfd_abs_symbol;
+.extern const struct symbol_cache_entry * const bfd_com_symbol;
+.extern const struct symbol_cache_entry * const bfd_und_symbol;
+.extern const struct symbol_cache_entry * const bfd_ind_symbol;
+.#define bfd_get_section_size_before_reloc(section) \
+. (section->reloc_done ? (abort(),1): (section)->_raw_size)
+.#define bfd_get_section_size_after_reloc(section) \
+. ((section->reloc_done) ? (section)->_cooked_size: (abort(),1))
+*/
+
+/* These symbols are global, not specific to any BFD. Therefore, anything
+ that tries to change them is broken, and should be repaired. */
+static const asymbol global_syms[] =
+{
+ /* the_bfd, name, value, attr, section [, udata] */
+ {0, BFD_COM_SECTION_NAME, 0, BSF_SECTION_SYM, (asection *) &bfd_com_section},
+ {0, BFD_UND_SECTION_NAME, 0, BSF_SECTION_SYM, (asection *) &bfd_und_section},
+ {0, BFD_ABS_SECTION_NAME, 0, BSF_SECTION_SYM, (asection *) &bfd_abs_section},
+ {0, BFD_IND_SECTION_NAME, 0, BSF_SECTION_SYM, (asection *) &bfd_ind_section},
+};
+
+#define STD_SECTION(SEC, FLAGS, SYM, NAME, IDX) \
+ const asymbol * const SYM = (asymbol *) &global_syms[IDX]; \
+ const asection SEC = \
+ { NAME, 0, 0, FLAGS, 0, 0, 0, 0, 0, 0, 0, 0, 0, (asection *) &SEC, \
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
+ (asymbol *) &global_syms[IDX], (asymbol **) &SYM, 0, 0 }
+
+STD_SECTION (bfd_com_section, SEC_IS_COMMON, bfd_com_symbol,
+ BFD_COM_SECTION_NAME, 0);
+STD_SECTION (bfd_und_section, 0, bfd_und_symbol, BFD_UND_SECTION_NAME, 1);
+STD_SECTION (bfd_abs_section, 0, bfd_abs_symbol, BFD_ABS_SECTION_NAME, 2);
+STD_SECTION (bfd_ind_section, 0, bfd_ind_symbol, BFD_IND_SECTION_NAME, 3);
+#undef STD_SECTION
+
+/*
+DOCDD
+INODE
+section prototypes, , typedef asection, Sections
+SUBSECTION
+ Section prototypes
+
+These are the functions exported by the section handling part of BFD.
+*/
+
+/*
+FUNCTION
+ bfd_get_section_by_name
+
+SYNOPSIS
+ asection *bfd_get_section_by_name(bfd *abfd, CONST char *name);
+
+DESCRIPTION
+ Run through @var{abfd} and return the one of the
+ <<asection>>s whose name matches @var{name}, otherwise <<NULL>>.
+ @xref{Sections}, for more information.
+
+ This should only be used in special cases; the normal way to process
+ all sections of a given name is to use <<bfd_map_over_sections>> and
+ <<strcmp>> on the name (or better yet, base it on the section flags
+ or something else) for each section.
+*/
+
+asection *
+bfd_get_section_by_name (abfd, name)
+ bfd *abfd;
+ CONST char *name;
+{
+ asection *sect;
+
+ for (sect = abfd->sections; sect != NULL; sect = sect->next)
+ if (!strcmp (sect->name, name))
+ return sect;
+ return NULL;
+}
+
+
+/*
+FUNCTION
+ bfd_make_section_old_way
+
+SYNOPSIS
+ asection *bfd_make_section_old_way(bfd *abfd, CONST char *name);
+
+DESCRIPTION
+ Create a new empty section called @var{name}
+ and attach it to the end of the chain of sections for the
+ BFD @var{abfd}. An attempt to create a section with a name which
+ is already in use returns its pointer without changing the
+ section chain.
+
+ It has the funny name since this is the way it used to be
+ before it was rewritten....
+
+ Possible errors are:
+ o <<bfd_error_invalid_operation>> -
+ If output has already started for this BFD.
+ o <<bfd_error_no_memory>> -
+ If memory allocation fails.
+
+*/
+
+
+asection *
+bfd_make_section_old_way (abfd, name)
+ bfd *abfd;
+ CONST char *name;
+{
+ asection *sec = bfd_get_section_by_name (abfd, name);
+ if (sec == (asection *) NULL)
+ {
+ sec = bfd_make_section (abfd, name);
+ }
+ return sec;
+}
+
+/*
+FUNCTION
+ bfd_make_section_anyway
+
+SYNOPSIS
+ asection *bfd_make_section_anyway(bfd *abfd, CONST char *name);
+
+DESCRIPTION
+ Create a new empty section called @var{name} and attach it to the end of
+ the chain of sections for @var{abfd}. Create a new section even if there
+ is already a section with that name.
+
+ Return <<NULL>> and set <<bfd_error>> on error; possible errors are:
+ o <<bfd_error_invalid_operation>> - If output has already started for @var{abfd}.
+ o <<bfd_error_no_memory>> - If memory allocation fails.
+*/
+
+sec_ptr
+bfd_make_section_anyway (abfd, name)
+ bfd *abfd;
+ CONST char *name;
+{
+ asection *newsect;
+ asection **prev = &abfd->sections;
+ asection *sect = abfd->sections;
+
+ if (abfd->output_has_begun)
+ {
+ bfd_set_error (bfd_error_invalid_operation);
+ return NULL;
+ }
+
+ while (sect)
+ {
+ prev = &sect->next;
+ sect = sect->next;
+ }
+
+ newsect = (asection *) bfd_zalloc (abfd, sizeof (asection));
+ if (newsect == NULL)
+ return NULL;
+
+ newsect->name = name;
+ newsect->index = abfd->section_count++;
+ newsect->flags = SEC_NO_FLAGS;
+
+ newsect->userdata = NULL;
+ newsect->contents = NULL;
+ newsect->next = (asection *) NULL;
+ newsect->relocation = (arelent *) NULL;
+ newsect->reloc_count = 0;
+ newsect->line_filepos = 0;
+ newsect->owner = abfd;
+
+ /* Create a symbol whos only job is to point to this section. This is
+ useful for things like relocs which are relative to the base of a
+ section. */
+ newsect->symbol = bfd_make_empty_symbol (abfd);
+ if (newsect->symbol == NULL)
+ return NULL;
+ newsect->symbol->name = name;
+ newsect->symbol->value = 0;
+ newsect->symbol->section = newsect;
+ newsect->symbol->flags = BSF_SECTION_SYM;
+
+ newsect->symbol_ptr_ptr = &newsect->symbol;
+
+ if (BFD_SEND (abfd, _new_section_hook, (abfd, newsect)) != true)
+ {
+ free (newsect);
+ return NULL;
+ }
+
+ *prev = newsect;
+ return newsect;
+}
+
+/*
+FUNCTION
+ bfd_make_section
+
+SYNOPSIS
+ asection *bfd_make_section(bfd *, CONST char *name);
+
+DESCRIPTION
+ Like <<bfd_make_section_anyway>>, but return <<NULL>> (without calling
+ bfd_set_error ()) without changing the section chain if there is already a
+ section named @var{name}. If there is an error, return <<NULL>> and set
+ <<bfd_error>>.
+*/
+
+asection *
+bfd_make_section (abfd, name)
+ bfd *abfd;
+ CONST char *name;
+{
+ asection *sect = abfd->sections;
+
+ if (strcmp (name, BFD_ABS_SECTION_NAME) == 0)
+ {
+ return bfd_abs_section_ptr;
+ }
+ if (strcmp (name, BFD_COM_SECTION_NAME) == 0)
+ {
+ return bfd_com_section_ptr;
+ }
+ if (strcmp (name, BFD_UND_SECTION_NAME) == 0)
+ {
+ return bfd_und_section_ptr;
+ }
+
+ if (strcmp (name, BFD_IND_SECTION_NAME) == 0)
+ {
+ return bfd_ind_section_ptr;
+ }
+
+ while (sect)
+ {
+ if (!strcmp (sect->name, name))
+ return NULL;
+ sect = sect->next;
+ }
+
+ /* The name is not already used; go ahead and make a new section. */
+ return bfd_make_section_anyway (abfd, name);
+}
+
+
+/*
+FUNCTION
+ bfd_set_section_flags
+
+SYNOPSIS
+ boolean bfd_set_section_flags(bfd *abfd, asection *sec, flagword flags);
+
+DESCRIPTION
+ Set the attributes of the section @var{sec} in the BFD
+ @var{abfd} to the value @var{flags}. Return <<true>> on success,
+ <<false>> on error. Possible error returns are:
+
+ o <<bfd_error_invalid_operation>> -
+ The section cannot have one or more of the attributes
+ requested. For example, a .bss section in <<a.out>> may not
+ have the <<SEC_HAS_CONTENTS>> field set.
+
+*/
+
+/*ARGSUSED*/
+boolean
+bfd_set_section_flags (abfd, section, flags)
+ bfd *abfd;
+ sec_ptr section;
+ flagword flags;
+{
+#if 0
+ /* If you try to copy a text section from an input file (where it
+ has the SEC_CODE flag set) to an output file, this loses big if
+ the bfd_applicable_section_flags (abfd) doesn't have the SEC_CODE
+ set - which it doesn't, at least not for a.out. FIXME */
+
+ if ((flags & bfd_applicable_section_flags (abfd)) != flags)
+ {
+ bfd_set_error (bfd_error_invalid_operation);
+ return false;
+ }
+#endif
+
+ section->flags = flags;
+ return true;
+}
+
+
+/*
+FUNCTION
+ bfd_map_over_sections
+
+SYNOPSIS
+ void bfd_map_over_sections(bfd *abfd,
+ void (*func)(bfd *abfd,
+ asection *sect,
+ PTR obj),
+ PTR obj);
+
+DESCRIPTION
+ Call the provided function @var{func} for each section
+ attached to the BFD @var{abfd}, passing @var{obj} as an
+ argument. The function will be called as if by
+
+| func(abfd, the_section, obj);
+
+ This is the prefered method for iterating over sections; an
+ alternative would be to use a loop:
+
+| section *p;
+| for (p = abfd->sections; p != NULL; p = p->next)
+| func(abfd, p, ...)
+
+
+*/
+
+/*VARARGS2*/
+void
+bfd_map_over_sections (abfd, operation, user_storage)
+ bfd *abfd;
+ void (*operation) PARAMS ((bfd * abfd, asection * sect, PTR obj));
+ PTR user_storage;
+{
+ asection *sect;
+ unsigned int i = 0;
+
+ for (sect = abfd->sections; sect != NULL; i++, sect = sect->next)
+ (*operation) (abfd, sect, user_storage);
+
+ if (i != abfd->section_count) /* Debugging */
+ abort ();
+}
+
+
+/*
+FUNCTION
+ bfd_set_section_size
+
+SYNOPSIS
+ boolean bfd_set_section_size(bfd *abfd, asection *sec, bfd_size_type val);
+
+DESCRIPTION
+ Set @var{sec} to the size @var{val}. If the operation is
+ ok, then <<true>> is returned, else <<false>>.
+
+ Possible error returns:
+ o <<bfd_error_invalid_operation>> -
+ Writing has started to the BFD, so setting the size is invalid.
+
+*/
+
+boolean
+bfd_set_section_size (abfd, ptr, val)
+ bfd *abfd;
+ sec_ptr ptr;
+ bfd_size_type val;
+{
+ /* Once you've started writing to any section you cannot create or change
+ the size of any others. */
+
+ if (abfd->output_has_begun)
+ {
+ bfd_set_error (bfd_error_invalid_operation);
+ return false;
+ }
+
+ ptr->_cooked_size = val;
+ ptr->_raw_size = val;
+
+ return true;
+}
+
+/*
+FUNCTION
+ bfd_set_section_contents
+
+SYNOPSIS
+ boolean bfd_set_section_contents
+ (bfd *abfd,
+ asection *section,
+ PTR data,
+ file_ptr offset,
+ bfd_size_type count);
+
+
+DESCRIPTION
+ Sets the contents of the section @var{section} in BFD
+ @var{abfd} to the data starting in memory at @var{data}. The
+ data is written to the output section starting at offset
+ @var{offset} for @var{count} bytes.
+
+
+
+ Normally <<true>> is returned, else <<false>>. Possible error
+ returns are:
+ o <<bfd_error_no_contents>> -
+ The output section does not have the <<SEC_HAS_CONTENTS>>
+ attribute, so nothing can be written to it.
+ o and some more too
+
+ This routine is front end to the back end function
+ <<_bfd_set_section_contents>>.
+
+
+*/
+
+#define bfd_get_section_size_now(abfd,sec) \
+(sec->reloc_done \
+ ? bfd_get_section_size_after_reloc (sec) \
+ : bfd_get_section_size_before_reloc (sec))
+
+boolean
+bfd_set_section_contents (abfd, section, location, offset, count)
+ bfd *abfd;
+ sec_ptr section;
+ PTR location;
+ file_ptr offset;
+ bfd_size_type count;
+{
+ bfd_size_type sz;
+
+ if (!(bfd_get_section_flags (abfd, section) & SEC_HAS_CONTENTS))
+ {
+ bfd_set_error (bfd_error_no_contents);
+ return (false);
+ }
+
+ if (offset < 0)
+ {
+ bad_val:
+ bfd_set_error (bfd_error_bad_value);
+ return false;
+ }
+ sz = bfd_get_section_size_now (abfd, section);
+ if ((bfd_size_type) offset > sz
+ || count > sz
+ || offset + count > sz)
+ goto bad_val;
+
+ switch (abfd->direction)
+ {
+ case read_direction:
+ case no_direction:
+ bfd_set_error (bfd_error_invalid_operation);
+ return false;
+
+ case write_direction:
+ break;
+
+ case both_direction:
+ /* File is opened for update. `output_has_begun' some time ago when
+ the file was created. Do not recompute sections sizes or alignments
+ in _bfd_set_section_content. */
+ abfd->output_has_begun = true;
+ break;
+ }
+
+ if (BFD_SEND (abfd, _bfd_set_section_contents,
+ (abfd, section, location, offset, count)))
+ {
+ abfd->output_has_begun = true;
+ return true;
+ }
+
+ return false;
+}
+
+/*
+FUNCTION
+ bfd_get_section_contents
+
+SYNOPSIS
+ boolean bfd_get_section_contents
+ (bfd *abfd, asection *section, PTR location,
+ file_ptr offset, bfd_size_type count);
+
+DESCRIPTION
+ Read data from @var{section} in BFD @var{abfd}
+ into memory starting at @var{location}. The data is read at an
+ offset of @var{offset} from the start of the input section,
+ and is read for @var{count} bytes.
+
+ If the contents of a constructor with the <<SEC_CONSTRUCTOR>>
+ flag set are requested or if the section does not have the
+ <<SEC_HAS_CONTENTS>> flag set, then the @var{location} is filled
+ with zeroes. If no errors occur, <<true>> is returned, else
+ <<false>>.
+
+
+
+*/
+boolean
+bfd_get_section_contents (abfd, section, location, offset, count)
+ bfd *abfd;
+ sec_ptr section;
+ PTR location;
+ file_ptr offset;
+ bfd_size_type count;
+{
+ bfd_size_type sz;
+
+ if (section->flags & SEC_CONSTRUCTOR)
+ {
+ memset (location, 0, (unsigned) count);
+ return true;
+ }
+
+ if (offset < 0)
+ {
+ bad_val:
+ bfd_set_error (bfd_error_bad_value);
+ return false;
+ }
+ /* Even if reloc_done is true, this function reads unrelocated
+ contents, so we want the raw size. */
+ sz = section->_raw_size;
+ if ((bfd_size_type) offset > sz || count > sz || offset + count > sz)
+ goto bad_val;
+
+ if (count == 0)
+ /* Don't bother. */
+ return true;
+
+ if ((section->flags & SEC_HAS_CONTENTS) == 0)
+ {
+ memset (location, 0, (unsigned) count);
+ return true;
+ }
+
+ if ((section->flags & SEC_IN_MEMORY) != 0)
+ {
+ memcpy (location, section->contents + offset, (size_t) count);
+ return true;
+ }
+
+ return BFD_SEND (abfd, _bfd_get_section_contents,
+ (abfd, section, location, offset, count));
+}
+
+/*
+FUNCTION
+ bfd_copy_private_section_data
+
+SYNOPSIS
+ boolean bfd_copy_private_section_data(bfd *ibfd, asection *isec, bfd *obfd, asection *osec);
+
+DESCRIPTION
+ Copy private section information from @var{isec} in the BFD
+ @var{ibfd} to the section @var{osec} in the BFD @var{obfd}.
+ Return <<true>> on success, <<false>> on error. Possible error
+ returns are:
+
+ o <<bfd_error_no_memory>> -
+ Not enough memory exists to create private data for @var{osec}.
+
+.#define bfd_copy_private_section_data(ibfd, isection, obfd, osection) \
+. BFD_SEND (obfd, _bfd_copy_private_section_data, \
+. (ibfd, isection, obfd, osection))
+*/
+
+/*
+FUNCTION
+ _bfd_strip_section_from_output
+
+SYNOPSIS
+ void _bfd_strip_section_from_output
+ (asection *section);
+
+DESCRIPTION
+ Remove @var{section} from the output. If the output section becomes
+ empty, remove it from the output bfd.
+*/
+void
+_bfd_strip_section_from_output (s)
+ asection *s;
+{
+ asection **spp, *os;
+ struct bfd_link_order *p, *pp;
+
+ os = s->output_section;
+ for (p = os->link_order_head, pp = NULL; p != NULL; pp = p, p = p->next)
+ if (p->type == bfd_indirect_link_order
+ && p->u.indirect.section == s)
+ {
+ /* Excise the input section. */
+ if (pp)
+ pp->next = p->next;
+ else
+ os->link_order_head = p->next;
+ if (!p->next)
+ os->link_order_tail = pp;
+
+ if (!os->link_order_head)
+ {
+ /* Excise the output section. */
+ for (spp = &os->owner->sections; *spp; spp = &(*spp)->next)
+ if (*spp == os)
+ {
+ *spp = os->next;
+ os->owner->section_count--;
+ break;
+ }
+ }
+ break;
+ }
+}