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1082 lines
31 KiB
C
1082 lines
31 KiB
C
/* Object file "section" support for the BFD library.
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Copyright (C) 1990, 91, 92, 93, 94, 95, 96, 1997
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Free Software Foundation, Inc.
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Written by Cygnus Support.
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This file is part of BFD, the Binary File Descriptor library.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
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/*
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SECTION
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Sections
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The raw data contained within a BFD is maintained through the
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section abstraction. A single BFD may have any number of
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sections. It keeps hold of them by pointing to the first;
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each one points to the next in the list.
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Sections are supported in BFD in <<section.c>>.
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@menu
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@* Section Input::
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@* Section Output::
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@* typedef asection::
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@* section prototypes::
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@end menu
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INODE
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Section Input, Section Output, Sections, Sections
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SUBSECTION
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Section input
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When a BFD is opened for reading, the section structures are
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created and attached to the BFD.
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Each section has a name which describes the section in the
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outside world---for example, <<a.out>> would contain at least
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three sections, called <<.text>>, <<.data>> and <<.bss>>.
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Names need not be unique; for example a COFF file may have several
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sections named <<.data>>.
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Sometimes a BFD will contain more than the ``natural'' number of
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sections. A back end may attach other sections containing
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constructor data, or an application may add a section (using
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<<bfd_make_section>>) to the sections attached to an already open
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BFD. For example, the linker creates an extra section
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<<COMMON>> for each input file's BFD to hold information about
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common storage.
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The raw data is not necessarily read in when
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the section descriptor is created. Some targets may leave the
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data in place until a <<bfd_get_section_contents>> call is
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made. Other back ends may read in all the data at once. For
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example, an S-record file has to be read once to determine the
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size of the data. An IEEE-695 file doesn't contain raw data in
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sections, but data and relocation expressions intermixed, so
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the data area has to be parsed to get out the data and
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relocations.
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INODE
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Section Output, typedef asection, Section Input, Sections
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SUBSECTION
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Section output
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To write a new object style BFD, the various sections to be
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written have to be created. They are attached to the BFD in
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the same way as input sections; data is written to the
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sections using <<bfd_set_section_contents>>.
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Any program that creates or combines sections (e.g., the assembler
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and linker) must use the <<asection>> fields <<output_section>> and
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<<output_offset>> to indicate the file sections to which each
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section must be written. (If the section is being created from
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scratch, <<output_section>> should probably point to the section
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itself and <<output_offset>> should probably be zero.)
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The data to be written comes from input sections attached
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(via <<output_section>> pointers) to
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the output sections. The output section structure can be
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considered a filter for the input section: the output section
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determines the vma of the output data and the name, but the
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input section determines the offset into the output section of
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the data to be written.
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E.g., to create a section "O", starting at 0x100, 0x123 long,
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containing two subsections, "A" at offset 0x0 (i.e., at vma
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0x100) and "B" at offset 0x20 (i.e., at vma 0x120) the <<asection>>
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structures would look like:
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| section name "A"
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| output_offset 0x00
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| size 0x20
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| output_section -----------> section name "O"
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| | vma 0x100
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| section name "B" | size 0x123
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| output_offset 0x20 |
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| size 0x103 |
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| output_section --------|
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SUBSECTION
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Link orders
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The data within a section is stored in a @dfn{link_order}.
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These are much like the fixups in <<gas>>. The link_order
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abstraction allows a section to grow and shrink within itself.
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A link_order knows how big it is, and which is the next
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link_order and where the raw data for it is; it also points to
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a list of relocations which apply to it.
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The link_order is used by the linker to perform relaxing on
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final code. The compiler creates code which is as big as
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necessary to make it work without relaxing, and the user can
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select whether to relax. Sometimes relaxing takes a lot of
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time. The linker runs around the relocations to see if any
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are attached to data which can be shrunk, if so it does it on
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a link_order by link_order basis.
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*/
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#include "bfd.h"
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#include "sysdep.h"
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#include "libbfd.h"
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#include "bfdlink.h"
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/*
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DOCDD
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INODE
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typedef asection, section prototypes, Section Output, Sections
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SUBSECTION
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typedef asection
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Here is the section structure:
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CODE_FRAGMENT
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.
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.typedef struct sec
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.{
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. {* The name of the section; the name isn't a copy, the pointer is
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. the same as that passed to bfd_make_section. *}
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.
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. CONST char *name;
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.
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. {* Which section is it; 0..nth. *}
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.
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. int index;
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.
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. {* The next section in the list belonging to the BFD, or NULL. *}
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.
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. struct sec *next;
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.
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. {* The field flags contains attributes of the section. Some
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. flags are read in from the object file, and some are
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. synthesized from other information. *}
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.
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. flagword flags;
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.
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.#define SEC_NO_FLAGS 0x000
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.
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. {* Tells the OS to allocate space for this section when loading.
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. This is clear for a section containing debug information
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. only. *}
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.#define SEC_ALLOC 0x001
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.
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. {* Tells the OS to load the section from the file when loading.
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. This is clear for a .bss section. *}
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.#define SEC_LOAD 0x002
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.
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. {* The section contains data still to be relocated, so there is
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. some relocation information too. *}
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.#define SEC_RELOC 0x004
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.
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.#if 0 {* Obsolete ? *}
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.#define SEC_BALIGN 0x008
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.#endif
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.
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. {* A signal to the OS that the section contains read only
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. data. *}
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.#define SEC_READONLY 0x010
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.
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. {* The section contains code only. *}
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.#define SEC_CODE 0x020
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.
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. {* The section contains data only. *}
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.#define SEC_DATA 0x040
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.
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. {* The section will reside in ROM. *}
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.#define SEC_ROM 0x080
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.
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. {* The section contains constructor information. This section
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. type is used by the linker to create lists of constructors and
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. destructors used by <<g++>>. When a back end sees a symbol
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. which should be used in a constructor list, it creates a new
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. section for the type of name (e.g., <<__CTOR_LIST__>>), attaches
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. the symbol to it, and builds a relocation. To build the lists
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. of constructors, all the linker has to do is catenate all the
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. sections called <<__CTOR_LIST__>> and relocate the data
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. contained within - exactly the operations it would peform on
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. standard data. *}
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.#define SEC_CONSTRUCTOR 0x100
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.
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. {* The section is a constructor, and should be placed at the
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. end of the text, data, or bss section(?). *}
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.#define SEC_CONSTRUCTOR_TEXT 0x1100
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.#define SEC_CONSTRUCTOR_DATA 0x2100
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.#define SEC_CONSTRUCTOR_BSS 0x3100
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.
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. {* The section has contents - a data section could be
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. <<SEC_ALLOC>> | <<SEC_HAS_CONTENTS>>; a debug section could be
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. <<SEC_HAS_CONTENTS>> *}
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.#define SEC_HAS_CONTENTS 0x200
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.
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. {* An instruction to the linker to not output the section
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. even if it has information which would normally be written. *}
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.#define SEC_NEVER_LOAD 0x400
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.
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. {* The section is a COFF shared library section. This flag is
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. only for the linker. If this type of section appears in
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. the input file, the linker must copy it to the output file
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. without changing the vma or size. FIXME: Although this
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. was originally intended to be general, it really is COFF
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. specific (and the flag was renamed to indicate this). It
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. might be cleaner to have some more general mechanism to
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. allow the back end to control what the linker does with
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. sections. *}
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.#define SEC_COFF_SHARED_LIBRARY 0x800
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.
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. {* The section contains common symbols (symbols may be defined
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. multiple times, the value of a symbol is the amount of
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. space it requires, and the largest symbol value is the one
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. used). Most targets have exactly one of these (which we
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. translate to bfd_com_section_ptr), but ECOFF has two. *}
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.#define SEC_IS_COMMON 0x8000
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.
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. {* The section contains only debugging information. For
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. example, this is set for ELF .debug and .stab sections.
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. strip tests this flag to see if a section can be
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. discarded. *}
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.#define SEC_DEBUGGING 0x10000
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.
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. {* The contents of this section are held in memory pointed to
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. by the contents field. This is checked by
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. bfd_get_section_contents, and the data is retrieved from
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. memory if appropriate. *}
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.#define SEC_IN_MEMORY 0x20000
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.
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. {* The contents of this section are to be excluded by the
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. linker for executable and shared objects unless those
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. objects are to be further relocated. *}
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.#define SEC_EXCLUDE 0x40000
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.
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. {* The contents of this section are to be sorted by the
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. based on the address specified in the associated symbol
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. table. *}
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.#define SEC_SORT_ENTRIES 0x80000
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.
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. {* When linking, duplicate sections of the same name should be
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. discarded, rather than being combined into a single section as
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. is usually done. This is similar to how common symbols are
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. handled. See SEC_LINK_DUPLICATES below. *}
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.#define SEC_LINK_ONCE 0x100000
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.
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. {* If SEC_LINK_ONCE is set, this bitfield describes how the linker
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. should handle duplicate sections. *}
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.#define SEC_LINK_DUPLICATES 0x600000
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.
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. {* This value for SEC_LINK_DUPLICATES means that duplicate
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. sections with the same name should simply be discarded. *}
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.#define SEC_LINK_DUPLICATES_DISCARD 0x0
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.
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. {* This value for SEC_LINK_DUPLICATES means that the linker
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. should warn if there are any duplicate sections, although
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. it should still only link one copy. *}
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.#define SEC_LINK_DUPLICATES_ONE_ONLY 0x200000
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.
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. {* This value for SEC_LINK_DUPLICATES means that the linker
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. should warn if any duplicate sections are a different size. *}
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.#define SEC_LINK_DUPLICATES_SAME_SIZE 0x400000
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.
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. {* This value for SEC_LINK_DUPLICATES means that the linker
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. should warn if any duplicate sections contain different
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. contents. *}
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.#define SEC_LINK_DUPLICATES_SAME_CONTENTS 0x600000
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.
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. {* This section was created by the linker as part of dynamic
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. relocation or other arcane processing. It is skipped when
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. going through the first-pass output, trusting that someone
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. else up the line will take care of it later. *}
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.#define SEC_LINKER_CREATED 0x800000
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.
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. {* This section should not be subject to garbage collection. *}
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.#define SEC_KEEP 0x1000000
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.
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. {* This section contains "short" data, and should be placed
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. "near" the GP. *}
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.#define SEC_SHORT 0x2000000
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.
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. {* End of section flags. *}
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.
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. {* Some internal packed boolean fields. *}
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.
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. {* See the vma field. *}
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. unsigned int user_set_vma : 1;
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.
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. {* Whether relocations have been processed. *}
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. unsigned int reloc_done : 1;
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.
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. {* A mark flag used by some of the linker backends. *}
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. unsigned int linker_mark : 1;
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.
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. {* A mark flag used by some linker backends for garbage collection. *}
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. unsigned int gc_mark : 1;
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.
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. {* End of internal packed boolean fields. *}
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.
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. {* The virtual memory address of the section - where it will be
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. at run time. The symbols are relocated against this. The
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. user_set_vma flag is maintained by bfd; if it's not set, the
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. backend can assign addresses (for example, in <<a.out>>, where
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. the default address for <<.data>> is dependent on the specific
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. target and various flags). *}
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.
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. bfd_vma vma;
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.
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. {* The load address of the section - where it would be in a
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. rom image; really only used for writing section header
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. information. *}
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.
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. bfd_vma lma;
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.
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. {* The size of the section in bytes, as it will be output.
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. contains a value even if the section has no contents (e.g., the
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. size of <<.bss>>). This will be filled in after relocation *}
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.
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. bfd_size_type _cooked_size;
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.
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. {* The original size on disk of the section, in bytes. Normally this
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. value is the same as the size, but if some relaxing has
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. been done, then this value will be bigger. *}
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.
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. bfd_size_type _raw_size;
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.
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. {* If this section is going to be output, then this value is the
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. offset into the output section of the first byte in the input
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. section. E.g., if this was going to start at the 100th byte in
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. the output section, this value would be 100. *}
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.
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. bfd_vma output_offset;
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.
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. {* The output section through which to map on output. *}
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.
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. struct sec *output_section;
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.
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. {* The alignment requirement of the section, as an exponent of 2 -
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. e.g., 3 aligns to 2^3 (or 8). *}
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.
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. unsigned int alignment_power;
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.
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. {* If an input section, a pointer to a vector of relocation
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. records for the data in this section. *}
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.
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. struct reloc_cache_entry *relocation;
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.
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. {* If an output section, a pointer to a vector of pointers to
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. relocation records for the data in this section. *}
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.
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. struct reloc_cache_entry **orelocation;
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.
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. {* The number of relocation records in one of the above *}
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.
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. unsigned reloc_count;
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.
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. {* Information below is back end specific - and not always used
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. or updated. *}
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.
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. {* File position of section data *}
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.
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. file_ptr filepos;
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.
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. {* File position of relocation info *}
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.
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. file_ptr rel_filepos;
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.
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. {* File position of line data *}
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.
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. file_ptr line_filepos;
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.
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. {* Pointer to data for applications *}
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.
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. PTR userdata;
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.
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. {* If the SEC_IN_MEMORY flag is set, this points to the actual
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. contents. *}
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. unsigned char *contents;
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.
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. {* Attached line number information *}
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.
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. alent *lineno;
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.
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. {* Number of line number records *}
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.
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. unsigned int lineno_count;
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.
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. {* When a section is being output, this value changes as more
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. linenumbers are written out *}
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.
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. file_ptr moving_line_filepos;
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.
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. {* What the section number is in the target world *}
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.
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. int target_index;
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.
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. PTR used_by_bfd;
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.
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. {* If this is a constructor section then here is a list of the
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. relocations created to relocate items within it. *}
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.
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. struct relent_chain *constructor_chain;
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.
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. {* The BFD which owns the section. *}
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.
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. bfd *owner;
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.
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. {* A symbol which points at this section only *}
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. struct symbol_cache_entry *symbol;
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. struct symbol_cache_entry **symbol_ptr_ptr;
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.
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. struct bfd_link_order *link_order_head;
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. struct bfd_link_order *link_order_tail;
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.} asection ;
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.
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. {* These sections are global, and are managed by BFD. The application
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. and target back end are not permitted to change the values in
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. these sections. New code should use the section_ptr macros rather
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. than referring directly to the const sections. The const sections
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. may eventually vanish. *}
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.#define BFD_ABS_SECTION_NAME "*ABS*"
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.#define BFD_UND_SECTION_NAME "*UND*"
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.#define BFD_COM_SECTION_NAME "*COM*"
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.#define BFD_IND_SECTION_NAME "*IND*"
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.
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. {* the absolute section *}
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.extern const asection bfd_abs_section;
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.#define bfd_abs_section_ptr ((asection *) &bfd_abs_section)
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.#define bfd_is_abs_section(sec) ((sec) == bfd_abs_section_ptr)
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. {* Pointer to the undefined section *}
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.extern const asection bfd_und_section;
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.#define bfd_und_section_ptr ((asection *) &bfd_und_section)
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.#define bfd_is_und_section(sec) ((sec) == bfd_und_section_ptr)
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. {* Pointer to the common section *}
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.extern const asection bfd_com_section;
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.#define bfd_com_section_ptr ((asection *) &bfd_com_section)
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. {* Pointer to the indirect section *}
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.extern const asection bfd_ind_section;
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.#define bfd_ind_section_ptr ((asection *) &bfd_ind_section)
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.#define bfd_is_ind_section(sec) ((sec) == bfd_ind_section_ptr)
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.
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.extern const struct symbol_cache_entry * const bfd_abs_symbol;
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.extern const struct symbol_cache_entry * const bfd_com_symbol;
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.extern const struct symbol_cache_entry * const bfd_und_symbol;
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.extern const struct symbol_cache_entry * const bfd_ind_symbol;
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.#define bfd_get_section_size_before_reloc(section) \
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|
. (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 = §->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) \
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. BFD_SEND (obfd, _bfd_copy_private_section_data, \
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|
. (ibfd, isection, obfd, osection))
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|
*/
|
|
|
|
/*
|
|
FUNCTION
|
|
_bfd_strip_section_from_output
|
|
|
|
SYNOPSIS
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|
void _bfd_strip_section_from_output
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|
(asection *section);
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|
|
|
DESCRIPTION
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|
Remove @var{section} from the output. If the output section becomes
|
|
empty, remove it from the output bfd.
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|
*/
|
|
void
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|
_bfd_strip_section_from_output (s)
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|
asection *s;
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|
{
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|
asection **spp, *os;
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|
struct bfd_link_order *p, *pp;
|
|
|
|
/* Excise the input section from the link order. */
|
|
os = s->output_section;
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|
for (p = os->link_order_head, pp = NULL; p != NULL; pp = p, p = p->next)
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|
if (p->type == bfd_indirect_link_order
|
|
&& p->u.indirect.section == s)
|
|
{
|
|
if (pp)
|
|
pp->next = p->next;
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|
else
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|
os->link_order_head = p->next;
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|
if (!p->next)
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|
os->link_order_tail = pp;
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|
break;
|
|
}
|
|
|
|
/* If the output section is empty, remove it too. Careful about sections
|
|
that have been discarded in the link script -- they are mapped to
|
|
bfd_abs_section, which has no owner. */
|
|
if (!os->link_order_head && os->owner)
|
|
{
|
|
for (spp = &os->owner->sections; *spp; spp = &(*spp)->next)
|
|
if (*spp == os)
|
|
{
|
|
*spp = os->next;
|
|
os->owner->section_count--;
|
|
break;
|
|
}
|
|
}
|
|
}
|