mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-24 07:31:32 +00:00
106 lines
4.0 KiB
Plaintext
106 lines
4.0 KiB
Plaintext
@section Archives
|
|
|
|
|
|
@strong{Description}@*
|
|
An archive (or library) is just another BFD. It has a symbol
|
|
table, although there's not much a user program will do with it.
|
|
|
|
The big difference between an archive BFD and an ordinary BFD
|
|
is that the archive doesn't have sections. Instead it has a
|
|
chain of BFDs that are considered its contents. These BFDs can
|
|
be manipulated like any other. The BFDs contained in an
|
|
archive opened for reading will all be opened for reading. You
|
|
may put either input or output BFDs into an archive opened for
|
|
output; they will be handled correctly when the archive is closed.
|
|
|
|
Use @code{bfd_openr_next_archived_file} to step through
|
|
the contents of an archive opened for input. You don't
|
|
have to read the entire archive if you don't want
|
|
to! Read it until you find what you want.
|
|
|
|
A BFD returned by @code{bfd_openr_next_archived_file} can be
|
|
closed manually with @code{bfd_close}. If you do not close it,
|
|
then a second iteration through the members of an archive may
|
|
return the same BFD. If you close the archive BFD, then all
|
|
the member BFDs will automatically be closed as well.
|
|
|
|
Archive contents of output BFDs are chained through the
|
|
@code{archive_next} pointer in a BFD. The first one is findable
|
|
through the @code{archive_head} slot of the archive. Set it with
|
|
@code{bfd_set_archive_head} (q.v.). A given BFD may be in only
|
|
one open output archive at a time.
|
|
|
|
As expected, the BFD archive code is more general than the
|
|
archive code of any given environment. BFD archives may
|
|
contain files of different formats (e.g., a.out and coff) and
|
|
even different architectures. You may even place archives
|
|
recursively into archives!
|
|
|
|
This can cause unexpected confusion, since some archive
|
|
formats are more expressive than others. For instance, Intel
|
|
COFF archives can preserve long filenames; SunOS a.out archives
|
|
cannot. If you move a file from the first to the second
|
|
format and back again, the filename may be truncated.
|
|
Likewise, different a.out environments have different
|
|
conventions as to how they truncate filenames, whether they
|
|
preserve directory names in filenames, etc. When
|
|
interoperating with native tools, be sure your files are
|
|
homogeneous.
|
|
|
|
Beware: most of these formats do not react well to the
|
|
presence of spaces in filenames. We do the best we can, but
|
|
can't always handle this case due to restrictions in the format of
|
|
archives. Many Unix utilities are braindead in regards to
|
|
spaces and such in filenames anyway, so this shouldn't be much
|
|
of a restriction.
|
|
|
|
Archives are supported in BFD in @code{archive.c}.
|
|
|
|
@subsection Archive functions
|
|
|
|
|
|
@findex bfd_get_next_mapent
|
|
@subsubsection @code{bfd_get_next_mapent}
|
|
@strong{Synopsis}
|
|
@example
|
|
symindex bfd_get_next_mapent
|
|
(bfd *abfd, symindex previous, carsym **sym);
|
|
@end example
|
|
@strong{Description}@*
|
|
Step through archive @var{abfd}'s symbol table (if it
|
|
has one). Successively update @var{sym} with the next symbol's
|
|
information, returning that symbol's (internal) index into the
|
|
symbol table.
|
|
|
|
Supply @code{BFD_NO_MORE_SYMBOLS} as the @var{previous} entry to get
|
|
the first one; returns @code{BFD_NO_MORE_SYMBOLS} when you've already
|
|
got the last one.
|
|
|
|
A @code{carsym} is a canonical archive symbol. The only
|
|
user-visible element is its name, a null-terminated string.
|
|
|
|
@findex bfd_set_archive_head
|
|
@subsubsection @code{bfd_set_archive_head}
|
|
@strong{Synopsis}
|
|
@example
|
|
bfd_boolean bfd_set_archive_head (bfd *output, bfd *new_head);
|
|
@end example
|
|
@strong{Description}@*
|
|
Set the head of the chain of
|
|
BFDs contained in the archive @var{output} to @var{new_head}.
|
|
|
|
@findex bfd_openr_next_archived_file
|
|
@subsubsection @code{bfd_openr_next_archived_file}
|
|
@strong{Synopsis}
|
|
@example
|
|
bfd *bfd_openr_next_archived_file (bfd *archive, bfd *previous);
|
|
@end example
|
|
@strong{Description}@*
|
|
Provided a BFD, @var{archive}, containing an archive and NULL, open
|
|
an input BFD on the first contained element and returns that.
|
|
Subsequent calls should pass
|
|
the archive and the previous return value to return a created
|
|
BFD to the next contained element. NULL is returned when there
|
|
are no more.
|
|
|