add target vector documentation
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@ -25,6 +25,7 @@ The initial version of this document was written by Ian Lance Taylor
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@menu
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* BFD glossary:: BFD glossary
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* BFD guidelines:: BFD programming guidelines
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* BFD target vector:: BFD target vector
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* BFD generated files:: BFD generated files
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* BFD multiple compilations:: Files compiled multiple times in BFD
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* BFD relocation handling:: BFD relocation handling
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@ -187,6 +188,645 @@ which may or may not be declared in system header files. Warnings about
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ambiguous expressions and the like should always be fixed.
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@end itemize
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@node BFD target vector
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@section BFD target vector
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@cindex bfd target vector
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@cindex target vector in bfd
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BFD supports multiple object file formats by using the @dfn{target
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vector}. This is simply a set of function pointers which implement
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behaviour that is specific to a particular object file format.
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In this section I list all of the entries in the target vector and
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describe what they do.
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@menu
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* BFD target vector miscellaneous:: Miscellaneous constants
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* BFD target vector swap:: Swapping functions
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* BFD target vector format:: Format type dependent functions
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* BFD_JUMP_TABLE macros:: BFD_JUMP_TABLE macros
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* BFD target vector generic:: Generic functions
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* BFD target vector copy:: Copy functions
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* BFD target vector core:: Core file support functions
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* BFD target vector archive:: Archive functions
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* BFD target vector symbols:: Symbol table functions
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* BFD target vector relocs:: Relocation support
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* BFD target vector write:: Output functions
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* BFD target vector link:: Linker functions
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* BFD target vector dynamic:: Dynamic linking information functions
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@end menu
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@node BFD target vector miscellaneous
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@subsection Miscellaneous constants
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The target vector starts with a set of constants.
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@table @samp
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@item name
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The name of the target vector. This is an arbitrary string. This is
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how the target vector is named in command line options for tools which
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use BFD, such as the @samp{-oformat} linker option.
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@item flavour
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A general description of the type of target. The following flavours are
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currently defined:
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@table @samp
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@item bfd_target_unknown_flavour
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Undefined or unknown.
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@item bfd_target_aout_flavour
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a.out.
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@item bfd_target_coff_flavour
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COFF.
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@item bfd_target_ecoff_flavour
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ECOFF.
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@item bfd_target_elf_flavour
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ELF.
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@item bfd_target_ieee_flavour
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IEEE-695.
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@item bfd_target_nlm_flavour
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NLM.
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@item bfd_target_oasys_flavour
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OASYS.
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@item bfd_target_tekhex_flavour
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Tektronix hex format.
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@item bfd_target_srec_flavour
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Motorola S-record format.
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@item bfd_target_ihex_flavour
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Intel hex format.
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@item bfd_target_som_flavour
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SOM (used on HP/UX).
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@item bfd_target_os9k_flavour
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os9000.
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@item bfd_target_versados_flavour
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VERSAdos.
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@item bfd_target_msdos_flavour
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MS-DOS.
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@item bfd_target_evax_flavour
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openVMS.
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@end table
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@item byteorder
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The byte order of data in the object file. One of
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@samp{BFD_ENDIAN_BIG}, @samp{BFD_ENDIAN_LITTLE}, or
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@samp{BFD_ENDIAN_UNKNOWN}. The latter would be used for a format such
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as S-records which do not record the architecture of the data.
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@item header_byteorder
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The byte order of header information in the object file. Normally the
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same as the @samp{byteorder} field, but there are certain cases where it
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may be different.
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@item object_flags
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Flags which may appear in the @samp{flags} field of a BFD with this
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format.
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@item section_flags
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Flags which may appear in the @samp{flags} field of a section within a
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BFD with this format.
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@item symbol_leading_char
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A character which the C compiler normally puts before a symbol. For
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example, an a.out compiler will typically generate the symbol
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@samp{_foo} for a function named @samp{foo} in the C source, in which
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case this field would be @samp{_}. If there is no such character, this
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field will be @samp{0}.
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@item ar_pad_char
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The padding character to use at the end of an archive name. Normally
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@samp{/}.
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@item ar_max_namelen
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The maximum length of a short name in an archive. Normally @samp{14}.
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@item backend_data
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A pointer to constant backend data. This is used by backends to store
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whatever additional information they need to distinguish similar target
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vectors which use the same sets of functions.
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@end table
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@node BFD target vector swap
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@subsection Swapping functions
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Every target vector has fuction pointers used for swapping information
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in and out of the target representation. There are two sets of
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functions: one for data information, and one for header information.
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Each set has three sizes: 64-bit, 32-bit, and 16-bit. Each size has
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three actual functions: put, get unsigned, and get signed.
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These 18 functions are used to convert data between the host and target
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representations.
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@node BFD target vector format
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@subsection Format type dependent functions
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Every target vector has three arrays of function pointers which are
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indexed by the BFD format type. The BFD format types are as follows:
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@table @samp
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@item bfd_unknown
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Unknown format. Not used for anything useful.
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@item bfd_object
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Object file.
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@item bfd_archive
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Archive file.
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@item bfd_core
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Core file.
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@end table
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The three arrays of function pointers are as follows:
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@table @samp
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@item bfd_check_format
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Check whether the BFD is of a particular format (object file, archive
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file, or core file) corresponding to this target vector. This is called
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by the @samp{bfd_check_format} function when examining an existing BFD.
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If the BFD matches the desired format, this function will initialize any
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format specific information such as the @samp{tdata} field of the BFD.
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This function must be called before any other BFD target vector function
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on a file opened for reading.
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@item bfd_set_format
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Set the format of a BFD which was created for output. This is called by
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the @samp{bfd_set_format} function after creating the BFD with a
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function such as @samp{bfd_openw}. This function will initialize format
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specific information required to write out an object file or whatever of
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the given format. This function must be called before any other BFD
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target vector function on a file opened for writing.
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@item bfd_write_contents
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Write out the contents of the BFD in the given format. This is called
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by @samp{bfd_close} function for a BFD opened for writing. This really
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should not be an array selected by format type, as the
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@samp{bfd_set_format} function provides all the required information.
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In fact, BFD will fail if a different format is used when calling
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through the @samp{bfd_set_format} and the @samp{bfd_write_contents}
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arrays; fortunately, since @samp{bfd_close} gets it right, this is a
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difficult error to make.
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@end table
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@node BFD_JUMP_TABLE macros
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@subsection @samp{BFD_JUMP_TABLE} macros
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@cindex @samp{BFD_JUMP_TABLE}
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Most target vectors are defined using @samp{BFD_JUMP_TABLE} macros.
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These macros take a single argument, which is a prefix applied to a set
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of functions. The macros are then used to initialize the fields in the
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target vector.
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For example, the @samp{BFD_JUMP_TABLE_RELOCS} macro defines three
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functions: @samp{_get_reloc_upper_bound}, @samp{_canonicalize_reloc},
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and @samp{_bfd_reloc_type_lookup}. A reference like
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@samp{BFD_JUMP_TABLE_RELOCS (foo)} will expand into three functions
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prefixed with @samp{foo}: @samp{foo_get_reloc_upper_found}, etc. The
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@samp{BFD_JUMP_TABLE_RELOCS} macro will be placed such that those three
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functions initialize the appropriate fields in the BFD target vector.
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This is done because it turns out that many different target vectors can
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shared certain classes of functions. For example, archives are similar
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on most platforms, so most target vectors can use the same archive
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functions. Those target vectors all use @samp{BFD_JUMP_TABLE_ARCHIVE}
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with the same argument, calling a set of functions which is defined in
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@file{archive.c}.
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Each of the @samp{BFD_JUMP_TABLE} macros is mentioned below along with
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the description of the function pointers which it defines. The function
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pointers will be described using the name without the prefix which the
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@samp{BFD_JUMP_TABLE} macro defines. This name is normally the same as
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the name of the field in the target vector structure. Any differences
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will be noted.
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@node BFD target vector generic
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@subsection Generic functions
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@cindex @samp{BFD_JUMP_TABLE_GENERIC}
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The @samp{BFD_JUMP_TABLE_GENERIC} macro is used for some catch all
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functions which don't easily fit into other categories.
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@table @samp
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@item _close_and_cleanup
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Free any target specific information associated with the BFD. This is
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called when any BFD is closed (the @samp{bfd_write_contents} function
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mentioned earlier is only called for a BFD opened for writing). Most
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targets use @samp{bfd_alloc} to allocate all target specific
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information, and therefore don't have to do anything in this function.
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This function pointer is typically set to
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@samp{_bfd_generic_close_and_cleanup}, which simply returns true.
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@item _bfd_free_cached_info
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Free any cached information associated with the BFD which can be
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recreated later if necessary. This is used to reduce the memory
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consumption required by programs using BFD. This is normally called via
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the @samp{bfd_free_cached_info} macro. It is used by the default
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archive routines when computing the archive map. Most targets do not
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do anything special for this entry point, and just set it to
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@samp{_bfd_generic_free_cached_info}, which simply returns true.
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@item _new_section_hook
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This is called from @samp{bfd_make_section_anyway} whenever a new
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section is created. Most targets use it to initialize section specific
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information. This function is called whether or not the section
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corresponds to an actual section in an actual BFD.
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@item _get_section_contents
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Get the contents of a section. This is called from
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@samp{bfd_get_section_contents}. Most targets set this to
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@samp{_bfd_generic_get_section_contents}, which does a @samp{bfd_seek}
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based on the section's @samp{filepos} field and a @samp{bfd_read}. The
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corresponding field in the target vector is named
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@samp{_bfd_get_section_contents}.
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@item _get_section_contents_in_window
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Set a @samp{bfd_window} to hold the contents of a section. This is
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called from @samp{bfd_get_section_contents_in_window}. The
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@samp{bfd_window} idea never really caught in, and I don't think this is
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ever called. Pretty much all targets implement this as
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@samp{bfd_generic_get_section_contents_in_window}, which uses
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@samp{bfd_get_section_contents} to do the right thing. The
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corresponding field in the target vector is named
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@samp{_bfd_get_section_contents_in_window}.
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@end table
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@node BFD target vector copy
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@subsection Copy functions
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@cindex @samp{BFD_JUMP_TABLE_COPY}
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The @samp{BFD_JUMP_TABLE_COPY} macro is used for functions which are
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called when copying BFDs, and for a couple of functions which deal with
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internal BFD information.
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@table @samp
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@item _bfd_copy_private_bfd_data
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This is called when copying a BFD, via @samp{bfd_copy_private_bfd_data}.
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If the input and output BFDs have the same format, this will copy any
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private information over. This is called after all the section contents
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have been written to the output file. Only a few targets do anything in
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this function.
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@item _bfd_merge_private_bfd_data
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This is called when linking, via @samp{bfd_merge_private_bfd_data}. It
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gives the backend linker code a chance to set any special flags in the
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output file based on the contents of the input file. Only a few targets
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do anything in this function.
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@item _bfd_copy_private_section_data
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This is similar to @samp{_bfd_copy_private_bfd_data}, but it is called
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for each section, via @samp{bfd_copy_private_section_data}. This
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function is called before any section contents have been written. Only
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a few targets do anything in this function.
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@item _bfd_copy_private_symbol_data
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This is called via @samp{bfd_copy_private_symbol_data}, but I don't
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think anything actually calls it. If it were defined, it could be used
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to copy private symbol data from one BFD to another. However, most BFDs
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store extra symbol information by allocating space which is larger than
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the @samp{asymbol} structure and storing private information in the
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extra space. Since @samp{objcopy} and other programs copy symbol
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information by copying pointers to @samp{asymbol} structures, the
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private symbol information is automatically copied as well. Most
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targets do not do anything in this function.
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@item _bfd_set_private_flags
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This is called via @samp{bfd_set_private_flags}. It is basically a hook
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for the assembler to set magic information. For example, the PowerPC
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ELF assembler uses it to set flags which appear in the e_flags field of
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the ELF header. Most targets do not do anything in this function.
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@item _bfd_print_private_bfd_data
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This is called by @samp{objdump} when the @samp{-p} option is used. It
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is called via @samp{bfd_print_private_data}. It prints any interesting
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information about the BFD which can not be otherwise represented by BFD
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and thus can not be printed by @samp{objdump}. Most targets do not do
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anything in this function.
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@end table
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@node BFD target vector core
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@subsection Core file support functions
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@cindex @samp{BFD_JUMP_TABLE_CORE}
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The @samp{BFD_JUMP_TABLE_CORE} macro is used for functions which deal
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with core files. Obviously, these functions only do something
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interesting for targets which have core file support.
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@table @samp
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@item _core_file_failing_command
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Given a core file, this returns the command which was run to produce the
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core file.
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@item _core_file_failing_signal
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Given a core file, this returns the signal number which produced the
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core file.
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@item _core_file_matches_executable_p
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Given a core file and a BFD for an executable, this returns whether the
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core file was generated by the executable.
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@end table
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@node BFD target vector archive
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@subsection Archive functions
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@cindex @samp{BFD_JUMP_TABLE_ARCHIVE}
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The @samp{BFD_JUMP_TABLE_ARCHIVE} macro is used for functions which deal
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with archive files. Most targets use COFF style archive files
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(including ELF targets), and these use @samp{_bfd_archive_coff} as the
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argument to @samp{BFD_JUMP_TABLE_ARCHIVE}. Some targets use BSD/a.out
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style archives, and these use @samp{_bfd_archive_bsd}. (The main
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difference between BSD and COFF archives is the format of the archive
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symbol table). Targets with no archive support use
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@samp{_bfd_noarchive}. Finally, a few targets have unusual archive
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handling.
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@table @samp
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@item _slurp_armap
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Read in the archive symbol table, storing it in private BFD data. This
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is normally called from the archive @samp{check_format} routine. The
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corresponding field in the target vector is named
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@samp{_bfd_slurp_armap}.
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@item _slurp_extended_name_table
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Read in the extended name table from the archive, if there is one,
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storing it in private BFD data. This is normally called from the
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archive @samp{check_format} routine. The corresponding field in the
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target vector is named @samp{_bfd_slurp_extended_name_table}.
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@item construct_extended_name_table
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Build and return an extended name table if one is needed to write out
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the archive. This also adjusts the archive headers to refer to the
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extended name table appropriately. This is normally called from the
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archive @samp{write_contents} routine. The corresponding field in the
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target vector is named @samp{_bfd_construct_extended_name_table}.
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@item _truncate_arname
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This copies a file name into an archive header, truncating it as
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required. It is normally called from the archive @samp{write_contents}
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routine. This function is more interesting in targets which do not
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support extended name tables, but I think the GNU @samp{ar} program
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always uses extended name tables anyhow. The corresponding field in the
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target vector is named @samp{_bfd_truncate_arname}.
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@item _write_armap
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Write out the archive symbol table using calls to @samp{bfd_write}.
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This is normally called from the archive @samp{write_contents} routine.
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The corresponding field in the target vector is named @samp{write_armap}
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(no leading underscore).
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@item _read_ar_hdr
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Read and parse an archive header. This handles expanding the archive
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header name into the real file name using the extended name table. This
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is called by routines which read the archive symbol table or the archive
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itself. The corresponding field in the target vector is named
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@samp{_bfd_read_ar_hdr_fn}.
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@item _openr_next_archived_file
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Given an archive and a BFD representing a file stored within the
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archive, return a BFD for the next file in the archive. This is called
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via @samp{bfd_openr_next_archived_file}. The corresponding field in the
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target vector is named @samp{openr_next_archived_file} (no leading
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underscore).
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@item _get_elt_at_index
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Given an archive and an index, return a BFD for the file in the archive
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corresponding to that entry in the archive symbol table. This is called
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via @samp{bfd_get_elt_at_index}. The corresponding field in the target
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vector is named @samp{_bfd_get_elt_at_index}.
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@item _generic_stat_arch_elt
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Do a stat on an element of an archive, returning information read from
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the archive header (modification time, uid, gid, file mode, size). This
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is called via @samp{bfd_stat_arch_elt}. The corresponding field in the
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target vector is named @samp{_bfd_stat_arch_elt}.
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@item _update_armap_timestamp
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After the entire contents of an archive have been written out, update
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the timestamp of the archive symbol table to be newer than that of the
|
||||
file. This is required for a.out style archives. This is normally
|
||||
called by the archive @samp{write_contents} routine. The corresponding
|
||||
field in the target vector is named @samp{_bfd_update_armap_timestamp}.
|
||||
@end table
|
||||
|
||||
@node BFD target vector symbols
|
||||
@subsection Symbol table functions
|
||||
@cindex @samp{BFD_JUMP_TABLE_SYMBOLS}
|
||||
|
||||
The @samp{BFD_JUMP_TABLE_SYMBOLS} macro is used for functions which deal
|
||||
with symbols.
|
||||
|
||||
@table @samp
|
||||
@item _get_symtab_upper_bound
|
||||
Return a sensible upper bound on the amount of memory which will be
|
||||
required to read the symbol table. In practice most targets return the
|
||||
amount of memory required to hold @samp{asymbol} pointers for all the
|
||||
symbols plus a trailing @samp{NULL} entry, and store the actual symbol
|
||||
information in BFD private data. This is called via
|
||||
@samp{bfd_get_symtab_upper_bound}. The corresponding field in the
|
||||
target vector is named @samp{_bfd_get_symtab_upper_bound}.
|
||||
|
||||
@item _get_symtab
|
||||
Read in the symbol table. This is called via
|
||||
@samp{bfd_canonicalize_symtab}. The corresponding field in the target
|
||||
vector is named @samp{_bfd_canonicalize_symtab}.
|
||||
|
||||
@item _make_empty_symbol
|
||||
Create an empty symbol for the BFD. This is needed because most targets
|
||||
store extra information with each symbol by allocating a structure
|
||||
larger than an @samp{asymbol} and storing the extra information at the
|
||||
end. This function will allocate the right amount of memory, and return
|
||||
what looks like a pointer to an empty @samp{asymbol}. This is called
|
||||
via @samp{bfd_make_empty_symbol}. The corresponding field in the target
|
||||
vector is named @samp{_bfd_make_empty_symbol}.
|
||||
|
||||
@item _print_symbol
|
||||
Print information about the symbol. This is called via
|
||||
@samp{bfd_print_symbol}. One of the arguments indicates what sort of
|
||||
information should be printed:
|
||||
@table @samp
|
||||
@item bfd_print_symbol_name
|
||||
Just print the symbol name.
|
||||
@item bfd_print_symbol_more
|
||||
Print the symbol name and some interesting flags. I don't think
|
||||
anything actually uses this.
|
||||
@item bfd_print_symbol_all
|
||||
Print all information about the symbol. This is used by @samp{objdump}
|
||||
when run with the @samp{-t} option.
|
||||
@end table
|
||||
The corresponding field in the target vector is named
|
||||
@samp{_bfd_print_symbol}.
|
||||
|
||||
@item _get_symbol_info
|
||||
Return a standard set of information about the symbol. This is called
|
||||
via @samp{bfd_symbol_info}. The corresponding field in the target
|
||||
vector is named @samp{_bfd_get_symbol_info}.
|
||||
|
||||
@item _bfd_is_local_label_name
|
||||
Return whether the given string would normally represent the name of a
|
||||
local label. This is called via @samp{bfd_is_local_label} and
|
||||
@samp{bfd_is_local_label_name}. Local labels are normally discarded by
|
||||
the assembler. In the linker, this defines the difference between the
|
||||
@samp{-x} and @samp{-X} options.
|
||||
|
||||
@item _get_lineno
|
||||
Return line number information for a symbol. This is only meaningful
|
||||
for a COFF target. This is called when writing out COFF line numbers.
|
||||
|
||||
@item _find_nearest_line
|
||||
Given an address within a section, use the debugging information to find
|
||||
the matching file name, function name, and line number, if any. This is
|
||||
called via @samp{bfd_find_nearest_line}. The corresponding field in the
|
||||
target vector is named @samp{_bfd_find_nearest_line}.
|
||||
|
||||
@item _bfd_make_debug_symbol
|
||||
Make a debugging symbol. This is only meaningful for a COFF target,
|
||||
where it simply returns a symbol which will be placed in the
|
||||
@samp{N_DEBUG} section when it is written out. This is called via
|
||||
@samp{bfd_make_debug_symbol}.
|
||||
|
||||
@item _read_minisymbols
|
||||
Minisymbols are used to reduce the memory requirements of programs like
|
||||
@samp{nm}. A minisymbol is a cookie pointing to internal symbol
|
||||
information which the caller can use to extract complete symbol
|
||||
information. This permits BFD to not convert all the symbols into
|
||||
generic form, but to instead convert them one at a time. This is called
|
||||
via @samp{bfd_read_minisymbols}. Most targets do not implement this,
|
||||
and just use generic support which is based on using standard
|
||||
@samp{asymbol} structures.
|
||||
|
||||
@item _minisymbol_to_symbol
|
||||
Convert a minisymbol to a standard @samp{asymbol}. This is called via
|
||||
@samp{bfd_minisymbol_to_symbol}.
|
||||
@end table
|
||||
|
||||
@node BFD target vector relocs
|
||||
@subsection Relocation support
|
||||
@cindex @samp{BFD_JUMP_TABLE_RELOCS}
|
||||
|
||||
The @samp{BFD_JUMP_TABLE_RELOCS} macro is used for functions which deal
|
||||
with relocations.
|
||||
|
||||
@table @samp
|
||||
@item _get_reloc_upper_bound
|
||||
Return a sensible upper bound on the amount of memory which will be
|
||||
required to read the relocations for a section. In practice most
|
||||
targets return the amount of memory required to hold @samp{arelent}
|
||||
pointers for all the relocations plus a trailing @samp{NULL} entry, and
|
||||
store the actual relocation information in BFD private data. This is
|
||||
called via @samp{bfd_get_reloc_upper_bound}.
|
||||
|
||||
@item _canonicalize_reloc
|
||||
Return the relocation information for a section. This is called via
|
||||
@samp{bfd_canonicalize_reloc}. The corresponding field in the target
|
||||
vector is named @samp{_bfd_canonicalize_reloc}.
|
||||
|
||||
@item _bfd_reloc_type_lookup
|
||||
Given a relocation code, return the corresponding howto structure
|
||||
(@pxref{BFD relocation codes}). This is called via
|
||||
@samp{bfd_reloc_type_lookup}. The corresponding field in the target
|
||||
vector is named @samp{reloc_type_lookup}.
|
||||
@end table
|
||||
|
||||
@node BFD target vector write
|
||||
@subsection Output functions
|
||||
@cindex @samp{BFD_JUMP_TABLE_WRITE}
|
||||
|
||||
The @samp{BFD_JUMP_TABLE_WRITE} macro is used for functions which deal
|
||||
with writing out a BFD.
|
||||
|
||||
@table @samp
|
||||
@item _set_arch_mach
|
||||
Set the architecture and machine number for a BFD. This is called via
|
||||
@samp{bfd_set_arch_mach}. Most targets implement this by calling
|
||||
@samp{bfd_default_set_arch_mach}. The corresponding field in the target
|
||||
vector is named @samp{_bfd_set_arch_mach}.
|
||||
|
||||
@item _set_section_contents
|
||||
Write out the contents of a section. This is called via
|
||||
@samp{bfd_set_section_contents}. The corresponding field in the target
|
||||
vector is named @samp{_bfd_set_section_contents}.
|
||||
@end table
|
||||
|
||||
@node BFD target vector link
|
||||
@subsection Linker functions
|
||||
@cindex @samp{BFD_JUMP_TABLE_LINK}
|
||||
|
||||
The @samp{BFD_JUMP_TABLE_LINK} macro is used for functions called by the
|
||||
linker.
|
||||
|
||||
@table @samp
|
||||
@item _sizeof_headers
|
||||
Return the size of the header information required for a BFD. This is
|
||||
used to implement the @samp{SIZEOF_HEADERS} linker script function. It
|
||||
is normally used to align the first section at an efficient position on
|
||||
the page. This is called via @samp{bfd_sizeof_headers}. The
|
||||
corresponding field in the target vector is named
|
||||
@samp{_bfd_sizeof_headers}.
|
||||
|
||||
@item _bfd_get_relocated_section_contents
|
||||
Read the contents of a section and apply the relocation information.
|
||||
This handles both a final link and a relocateable link; in the latter
|
||||
case, it adjust the relocation information as well. This is called via
|
||||
@samp{bfd_get_relocated_section_contents}. Most targets implement it by
|
||||
calling @samp{bfd_generic_get_relocated_section_contents}.
|
||||
|
||||
@item _bfd_relax_section
|
||||
Try to use relaxation to shrink the size of a section. This is called
|
||||
by the linker when the @samp{-relax} option is used. This is called via
|
||||
@samp{bfd_relax_section}. Most targets do not support any sort of
|
||||
relaxation.
|
||||
|
||||
@item _bfd_link_hash_table_create
|
||||
Create the symbol hash table to use for the linker. This linker hook
|
||||
permits the backend to control the size and information of the elements
|
||||
in the linker symbol hash table. This is called via
|
||||
@samp{bfd_link_hash_table_create}.
|
||||
|
||||
@item _bfd_link_add_symbols
|
||||
Given an object file or an archive, add all symbols into the linker
|
||||
symbol hash table. Use callbacks to the linker to include archive
|
||||
elements in the link. This is called via @samp{bfd_link_add_symbols}.
|
||||
|
||||
@item _bfd_final_link
|
||||
Finish the linking process. The linker calls this hook after all of the
|
||||
input files have been read, when it is ready to finish the link and
|
||||
generate the output file. This is called via @samp{bfd_final_link}.
|
||||
|
||||
@item _bfd_link_split_section
|
||||
I don't know what this is for. Nothing seems to call it. The only
|
||||
non-trivial definition is in @file{som.c}.
|
||||
@end table
|
||||
|
||||
@node BFD target vector dynamic
|
||||
@subsection Dynamic linking information functions
|
||||
@cindex @samp{BFD_JUMP_TABLE_DYNAMIC}
|
||||
|
||||
The @samp{BFD_JUMP_TABLE_DYNAMIC} macro is used for functions which read
|
||||
dynamic linking information.
|
||||
|
||||
@table @samp
|
||||
@item _get_dynamic_symtab_upper_bound
|
||||
Return a sensible upper bound on the amount of memory which will be
|
||||
required to read the dynamic symbol table. In practice most targets
|
||||
return the amount of memory required to hold @samp{asymbol} pointers for
|
||||
all the symbols plus a trailing @samp{NULL} entry, and store the actual
|
||||
symbol information in BFD private data. This is called via
|
||||
@samp{bfd_get_dynamic_symtab_upper_bound}. The corresponding field in
|
||||
the target vector is named @samp{_bfd_get_dynamic_symtab_upper_bound}.
|
||||
|
||||
@item _canonicalize_dynamic_symtab
|
||||
Read the dynamic symbol table. This is called via
|
||||
@samp{bfd_canonicalize_dynamic_symtab}. The corresponding field in the
|
||||
target vector is named @samp{_bfd_canonicalize_dynamic_symtab}.
|
||||
|
||||
@item _get_dynamic_reloc_upper_bound
|
||||
Return a sensible upper bound on the amount of memory which will be
|
||||
required to read the dynamic relocations. In practice most targets
|
||||
return the amount of memory required to hold @samp{arelent} pointers for
|
||||
all the relocations plus a trailing @samp{NULL} entry, and store the
|
||||
actual relocation information in BFD private data. This is called via
|
||||
@samp{bfd_get_dynamic_reloc_upper_bound}. The corresponding field in
|
||||
the target vector is named @samp{_bfd_get_dynamic_reloc_upper_bound}.
|
||||
|
||||
@item _canonicalize_dynamic_reloc
|
||||
Read the dynamic relocations. This is called via
|
||||
@samp{bfd_canonicalize_dynamic_reloc}. The corresponding field in the
|
||||
target vector is named @samp{_bfd_canonicalize_dynamic_reloc}.
|
||||
@end table
|
||||
|
||||
@node BFD generated files
|
||||
@section BFD generated files
|
||||
@cindex generated files in bfd
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue