Add -R (rescan or refresh) option to rescan and rebuild the hints

file based on the previous list of directories stored there which
should overcome a weakness of the '-m' switch which can only add
libs.  This is an ideal way of updating the hints list after adding
or removing a shlib since it will remove entries that are gone and
doesn't need to have all the directories spelled out each time.
(eg: rm -f /usr/lib/libtcl75*; ldconfig -R)  This only works for
version 2 hints files (which we've been generating for a year or
so) which store the path.

2 files changed, 27 insertions, 13 deletions

diff --git a/sbin/ldconfig/ldconfig.8 b/sbin/ldconfig/ldconfig.8
index 3aee7bd533b4..6f97599e1bad 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 1.12 1997/02/22 15:46:37 peter Exp $
+.\"	$Id: ldconfig.8,v 1.13 1997/07/11 14:45:40 jkh Exp $
 .\"
 .Dd October 3, 1993
 .Dt LDCONFIG 8
@@ -37,7 +37,7 @@
 .Nd configure the shared library cache
 .Sh SYNOPSIS
 .Nm ldconfig
-.Op Fl mrsv
+.Op Fl Rmrsv
 .Op Fl f Ar hints_file
 .Op Ar directory | file Ar ...
 .Sh DESCRIPTION
@@ -90,6 +90,10 @@ is typically run as part of the boot sequence.
 The following options recognized by
 .Nm ldconfig:
 .Bl -tag -width indent
+.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 .
@@ -104,7 +108,8 @@ Directories recorded in the hints file by previous runs of
 are also rescanned for new shared libraries.
 .It Fl r
 List the current contents of the hints file
-on the standard output. The hints file is not modified.
+on the standard output. The hints file is not modified.  The list of
+directories stored in the hints file is included.
 .It Fl s
 Do not scan the built-in system directory
 .Pq Dq /usr/lib
diff --git a/sbin/ldconfig/ldconfig.c b/sbin/ldconfig/ldconfig.c
index 3eed70a3a049..1f54178ce7a0 100644
--- a/sbin/ldconfig/ldconfig.c
+++ b/sbin/ldconfig/ldconfig.c
@@ -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.c,v 1.18 1997/02/22 15:46:38 peter Exp $
+ *	$Id: ldconfig.c,v 1.19 1997/07/11 14:45:41 jkh Exp $
  */
 
 #include <sys/param.h>
@@ -66,12 +66,11 @@
 #undef major
 #undef minor
 
-extern char			*__progname;
-
 static int			verbose;
 static int			nostd;
 static int			justread;
 static int			merge;
+static int			rescan;
 static char			*hints_file = _PATH_LD_HINTS;
 
 struct shlib_list {
@@ -102,8 +101,11 @@ char	*argv[];
 	int		i, c;
 	int		rval = 0;
 
-	while ((c = getopt(argc, argv, "f:mrsv")) != EOF) {
+	while ((c = getopt(argc, argv, "Rf:mrsv")) != EOF) {
 		switch (c) {
+		case 'R':
+			rescan = 1;
+			break;
 		case 'f':
 			hints_file = optarg;
 			break;
@@ -120,20 +122,20 @@ char	*argv[];
 			verbose = 1;
 			break;
 		default:
-			errx(1, "Usage: %s [-mrsv] [-f hints_file] [dir | file ...]",
-				__progname);
+			errx(1, "Usage: %s [-Rmrsv] [-f hints_file] "
+				"[dir | file ...]", argv[0]);
 			break;
 		}
 	}
 
 	dir_list = strdup("");
 
-	if (justread || merge) {
+	if (justread || merge || rescan) {
 		if ((rval = readhints()) != 0)
 			return rval;
 	}
 
-	if (!nostd && !merge)
+	if (!nostd && !merge && !rescan)
 		std_search_path();
 
 	/* Add any directories/files from the command line */
@@ -525,6 +527,15 @@ readhints()
 	blist = (struct hints_bucket *)(addr + hdr->hh_hashtab);
 	strtab = (char *)(addr + hdr->hh_strtab);
 
+	if (hdr->hh_version >= LD_HINTS_VERSION_2)
+		add_search_path(strtab + hdr->hh_dirlist);
+	else if (rescan)
+		errx(1, "%s too old and does not contain the search path",
+			hints_file);
+
+	if (rescan)
+		return 0;
+
 	for (i = 0; i < hdr->hh_nbucket; i++) {
 		struct hints_bucket	*bp = &blist[i];
 
@@ -549,8 +560,6 @@ readhints()
 		*shlib_tail = shp;
 		shlib_tail = &shp->next;
 	}
-	if (hdr->hh_version >= LD_HINTS_VERSION_2)
-		add_search_path(strtab + hdr->hh_dirlist);
 
 	return 0;
 }