Implement support for LD_PRELOAD in the dynamic linker.

Submitted by:	Doug Ambrisko <ambrisko@ambrisko.roble.com>

3 files changed, 56 insertions, 3 deletions

diff --git a/gnu/usr.bin/ld/ld.h b/gnu/usr.bin/ld/ld.h
index 468dbff..f16b3f8 100644
--- a/gnu/usr.bin/ld/ld.h
+++ b/gnu/usr.bin/ld/ld.h
@@ -1,5 +1,5 @@
 /*
- *	$Id: ld.h,v 1.14 1995/05/30 05:01:45 rgrimes Exp $
+ *	$Id: ld.h,v 1.15 1996/01/13 00:14:52 jdp Exp $
  */
 /*-
  * This code is derived from software copyrighted by the Free Software
@@ -643,6 +643,7 @@ int	findlib __P((struct file_entry *));
 
 /* In shlib.c: */
 char	*findshlib __P((char *, int *, int *, int));
+char	*find_lib_file __P((char *));
 char	*search_lib_dir __P((char *, char *, int *, int *, int));
 void	add_search_dir __P((char *));
 void	add_search_path __P((char *));
diff --git a/gnu/usr.bin/ld/shlib.c b/gnu/usr.bin/ld/shlib.c
index 04af10a..9460d35 100644
--- a/gnu/usr.bin/ld/shlib.c
+++ b/gnu/usr.bin/ld/shlib.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: shlib.c,v 1.13 1995/03/19 21:20:09 nate Exp $
+ *	$Id: shlib.c,v 1.14 1996/01/13 00:14:53 jdp Exp $
  */
 
 #include <sys/param.h>
@@ -204,6 +204,32 @@ int	do_dot_a;
 }
 
 /*
+ * Search library directories for a file with the given name.  The
+ * return value is a full pathname to the matching file.  The string
+ * is dynamically allocated.  If no matching file is found, the function
+ * returns NULL.
+ */
+
+char *
+find_lib_file(name)
+	char	*name;
+{
+	int		i;
+
+	for (i = 0; i < n_search_dirs; i++) {
+		char		*path = concat(search_dirs[i], "/", name);
+		struct stat	sb;
+
+		if (lstat(path, &sb) != -1)	/* We found it */
+			return path;
+
+		free(path);
+	}
+
+	return NULL;
+}
+
+/*
  * Search a given directory for a library (preferably shared) satisfying
  * the given criteria.
  *
diff --git a/libexec/rtld-aout/shlib.c b/libexec/rtld-aout/shlib.c
index 04af10a..9460d35 100644
--- a/libexec/rtld-aout/shlib.c
+++ b/libexec/rtld-aout/shlib.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: shlib.c,v 1.13 1995/03/19 21:20:09 nate Exp $
+ *	$Id: shlib.c,v 1.14 1996/01/13 00:14:53 jdp Exp $
  */
 
 #include <sys/param.h>
@@ -204,6 +204,32 @@ int	do_dot_a;
 }
 
 /*
+ * Search library directories for a file with the given name.  The
+ * return value is a full pathname to the matching file.  The string
+ * is dynamically allocated.  If no matching file is found, the function
+ * returns NULL.
+ */
+
+char *
+find_lib_file(name)
+	char	*name;
+{
+	int		i;
+
+	for (i = 0; i < n_search_dirs; i++) {
+		char		*path = concat(search_dirs[i], "/", name);
+		struct stat	sb;
+
+		if (lstat(path, &sb) != -1)	/* We found it */
+			return path;
+
+		free(path);
+	}
+
+	return NULL;
+}
+
+/*
  * Search a given directory for a library (preferably shared) satisfying
  * the given criteria.
  *