Implement ldconfig functionality for ELF. The hints are stored in

a different file than the a.out hints, namely, "/var/run/ld-elf.so.hints".
These hints consist only of the directory search path.  There is
no hash table as in the a.out hints, because ELF doesn't have to
search for the file with the highest minor version number.  (It
doesn't have minor version numbers at all.)

A single run of ldconfig updates either the a.out hints or the ELF
hints, but not both.  The set of hints to process is selected in
the usual way, via /etc/objformat, or ${OBJFORMAT}, or the "-aout"
or "-elf" command line option.  The rationale is that you probably
want to search different directories for ELF than for a.out.

"ldconfig -r" is faked up to produce output like we are used to,
except that for ELF there are no minor version numbers.  This should
enable "ldconfig -r" to be used for checking LIB_DEPENDS in ports
even for ELF.

I implemented the ELF functionality in a new source file, with an
eye toward eliminating the a.out code entirely at some point in
the future.

1 files changed, 52 insertions, 20 deletions

diff --git a/sbin/ldconfig/ldconfig.8 b/sbin/ldconfig/ldconfig.8
index 1f79ce8..9c4fd95 100644
--- a/sbin/ldconfig/ldconfig.8
+++ b/sbin/ldconfig/ldconfig.8
@@ -27,7 +27,7 @@
 .\" (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: ldconfig.8,v 1.14 1997/08/22 04:42:12 peter Exp $
+.\"	$Id: ldconfig.8,v 1.15 1998/01/01 02:31:47 alex Exp $
 .\"
 .Dd October 3, 1993
 .Dt LDCONFIG 8
@@ -37,6 +37,7 @@
 .Nd configure the shared library cache
 .Sh SYNOPSIS
 .Nm ldconfig
+.Op Fl aout | Fl elf
 .Op Fl Rmrsv
 .Op Fl f Ar hints_file
 .Op Ar directory | file Ar ...
@@ -44,25 +45,21 @@
 .Nm
 is used to prepare a set of
 .Dq hints
-for use by the run-time linker
-.Xr ld.so 1
+for use by the dynamic linker
 to facilitate quick lookup of shared libraries available in multiple
 directories.  It scans a set of built-in system directories and any
 .Ar directories
-specified on the command line (in the given order) looking for shared
-libraries and stores the results in the file
-.Pa /var/run/ld.so.hints
-to forestall the overhead that would otherwise result from the
-directory search operations
-.Xr ld.so 1
-would have to perform to load the required shared libraries.
+specified on the command line (in the given order) looking for
+shared libraries and stores the results in a system file to forestall
+the overhead that would otherwise result from the directory search
+operations the dynamic linker would have to perform to load the
+required shared libraries.
 .Pp
 Files named on the command line are expected to contain directories
 to scan for shared libraries.  Each directory's pathname must start on a new
 line.  Blank lines and lines starting with the comment character
 .Ql \&#
-are ignored.  A standard name for this file is
-.Xr /etc/ld.so.conf.
+are ignored.
 .Pp
 The shared libraries so found will be automatically available for loading
 if needed by the program being prepared for execution. This obviates the need
@@ -77,7 +74,7 @@ directories where shared libraries might be found.
 is a
 .Sq \:
 separated list of directory paths which are searched by
-.Xr ld.so 1
+the dynamic linker
 when it needs to load a shared library. It can be viewed as the run-time
 equivalent of the
 .Fl L
@@ -90,13 +87,16 @@ is typically run as part of the boot sequence.
 The following options recognized by
 .Nm ldconfig:
 .Bl -tag -width indent
+.It Fl aout
+Generate the hints for a.out format shared libraries.
+.It Fl elf
+Generate the hints for ELF format shared libraries.
 .It Fl R
 Rescan the previously configured directories.  This opens the previous hints
 file and fetches the directory list from the header.  Any additional pathnames
 on the command line are also processed.
 .It Fl f Ar hints_file
-Read and/or update the specified hints file, instead of
-.Pa /var/run/ld.so.hints .
+Read and/or update the specified hints file, instead of the standard file.
 This option is provided primarily for testing.
 .It Fl m
 Instead of replacing the contents of the hints file
@@ -121,7 +121,7 @@ Special care must be taken when loading shared libraries into the address
 space of
 .Ev set-user-Id
 programs. Whenever such a program is run,
-.Nm ld.so
+the dynamic linker
 will only load shared libraries from the hints
 file. In particular, the
 .Ev LD_LIBRARY_PATH
@@ -131,12 +131,44 @@ specify the trusted collection of directories from which shared objects can
 be safely loaded. It is presumed that the set of directories specified to
 .Nm ldconfig
 are under control of the system's administrator.
+.Sh ENVIRONMENT
+.Bl -tag -width OBJFORMATxxx -compact
+.It Ev OBJFORMAT
+Overrides
+.Pa /etc/objformat
+(see below) to determine whether
+.Fl aout
+or
+.Fl elf
+is the default.  If set, its value should be either
+.Ql aout
+or
+.Ql elf .
+.El
 .Sh FILES
-.Bl -tag -width /var/run/ld.so.hintsxxx -compact
+.Bl -tag -width /var/run/ld-elf.so.hintsxxx -compact
 .It Pa /var/run/ld.so.hints
-Default
-.Dq hints
-file.
+Standard hints file for the a.out dynamic linker.
+.It Pa /var/run/ld-elf.so.hints
+Standard hints file for the ELF dynamic linker.
+.It Pa /etc/ld.so.conf
+Conventional configuration file containing directory names for
+invocations with
+.Fl aout .
+.It Pa /etc/ld-elf.so.conf
+Conventional configuration file containing directory names for
+invocations with
+.Fl elf .
+.It Pa /etc/objformat
+Determines whether
+.Fl aout
+or
+.Fl elf
+is the default.  If present, it must consist of a single line
+containing either
+.Ql OBJFORMAT=aout
+or
+.Ql OBJFORMAT=elf .
 .Sh SEE ALSO
 .Xr ld 1 ,
 .Xr link 5