Add a new library function getobjformat(). It checks all the

standard places ("/etc/objformat", ${OBJFORMAT}, argv) for an
indication of the user's preferred object file format.  This
consolidates some code that was starting to be duplicated in more
and more places.

Use the new function in ldconfig.

Note: I don't think that gcc should use getobjformat(), even though
it could.  The compiler should limit itself to functions that are
widespread, to ease porting and cross-compilation.

1 files changed, 114 insertions, 0 deletions

diff --git a/lib/libc/gen/getobjformat.3 b/lib/libc/gen/getobjformat.3
new file mode 100644
index 0000000..228bb5f
--- /dev/null
+++ b/lib/libc/gen/getobjformat.3
@@ -0,0 +1,114 @@
+.\" Copyright (c) 1998 John D. Polstra
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" $Id$
+.\"
+.Dd September 7, 1998
+.Dt GETOBJFORMAT 3
+.Os FreeBSD
+.Sh NAME
+.Nm getobjformat
+.Nd get preferred object file format
+.Sh SYNOPSIS
+.Fd #include <objformat.h>
+.Ft int
+.Fn getobjformat "char *buf" "size_t bufsize" "int *argcp" "char **argv"
+.Sh DESCRIPTION
+.Fn getobjformat
+queries several sources to determine the preferred object file
+format, and copies its name into a buffer provided by the caller.
+.Pp
+The object file format is determined as follows.  If
+.Va argv
+is
+.No non- Ns Ev NULL
+and an explicit command line argument such as
+.Fl aout
+or
+.Fl elf
+is present, then that determines the object file format.
+.Pp
+Otherwise, if the variable
+.Ev OBJFORMAT
+is set in the environment, the object file format is taken from its
+value.
+.Pp
+Otherwise, if the file
+.Pa /etc/objformat
+is readable and contains a line of the form
+.Ql OBJFORMAT=xxx ,
+the object file format is taken from there.
+.Pp
+Otherwise, a built-in system default object file format is returned.
+.Pp
+.Va buf
+points to a user-supplied buffer into which the name of the object
+file format is copied.
+.Va bufsize
+gives the size of the buffer in bytes.  The string placed in
+.Va buf
+is always null-terminated.  It is an error if the buffer is too
+small to hold the null-terminated name.
+.Pp
+.Va argv
+points to a
+.Dv NULL Ns -terminated
+argument vector to be scanned for object
+format options.
+.Va argv
+may be
+.Dv NULL ,
+in which case the argument vector is not scanned.
+.Pp
+If
+.Va argcp
+is non-NULL, any object format options are deleted from the
+argument vector, and the updated argument count is stored into
+the integer referenced by
+.Va argcp .
+If
+.Va argcp
+is
+.Dv NULL ,
+the argument vector is left unchanged.
+.Sh RETURN VALUES
+On success,
+.Fn getobjformat
+returns the length of the object file format name, not counting the
+null terminator.
+If the supplied buffer is too small to hold the object file format
+and its null terminator,
+.Fn getobjformat
+returns -1.  In that case, the contents of the buffer and argument
+vector supplied by the caller are indeterminate.
+.Sh ENVIRONMENT
+.Ev OBJFORMAT
+.Sh FILES
+.Pa /etc/objformat
+.Sh SEE ALSO
+.Xr objformat 1
+.Sh HISTORY
+The
+.Fn getobjformat
+function first appeared in FreeBSD 3.0.