Index: usr.bin/xinstall/install.1
===================================================================
--- usr.bin/xinstall/install.1
+++ usr.bin/xinstall/install.1
@@ -187,11 +187,25 @@
 symbolic
 .It Sy m
 mixed
+.It Sy c
+metalog contents reference
 .El
 .Pp
 Absolute and relative have effect only for symbolic links.
 Mixed links
 are hard links for files on the same filesystem, symbolic otherwise.
+.Pp
+The
+.Ar c
+link type does not create a filesystem object.
+Instead, the source file's absolute path is recorded using the
+.Xr mtree 5
+.Cm contents
+tag in the
+.Ar metalog
+file.
+It must be used with
+.Fl M Ar metalog .
 .It Fl M Ar metalog
 Write the metadata associated with each item installed to
 .Ar metalog
Index: usr.bin/xinstall/tests/install_test.sh
===================================================================
--- usr.bin/xinstall/tests/install_test.sh
+++ usr.bin/xinstall/tests/install_test.sh
@@ -32,6 +32,8 @@
 	    install -s -d dir1
 	atf_check -s not-exit:0 -e match:"specified together" \
 	    install -s -l s testf copyf
+	atf_check -s not-exit:0 -e match:"requires -M metalog" \
+	    install -l c testf copyf
 }
 
 atf_test_case copy_to_empty
Index: usr.bin/xinstall/xinstall.c
===================================================================
--- usr.bin/xinstall/xinstall.c
+++ usr.bin/xinstall/xinstall.c
@@ -95,6 +95,7 @@
 #define	LN_HARD		0x04
 #define	LN_SYMBOLIC	0x08
 #define	LN_MIXED	0x10
+#define	LN_CONTENTS	0x20
 
 #define	DIRECTORY	0x01		/* Tell install it's a directory. */
 #define	SETFLAGS	0x02		/* Tell install to set flags. */
@@ -155,7 +156,8 @@
 static void	install(const char *, const char *, u_long, u_int);
 static void	install_dir(char *);
 static void	metadata_log(const char *, const char *, struct timespec *,
-		    const char *, const char *, off_t);
+		    const char *, const char *, off_t, const char *);
+static void	parse_l_args(const char *p);
 static int	parseid(const char *, id_t *);
 static int	strip(const char *, int, const char *, char **);
 static void	usage(void);
@@ -168,7 +170,6 @@
 	u_long fset;
 	int ch, no_target;
 	u_int iflags;
-	char *p;
 	const char *to_name;
 	uint64_t num;
 
@@ -209,32 +210,7 @@
 			digest = optarg;
 			break;
 		case 'l':
-			for (p = optarg; *p != '\0'; p++)
-				switch (*p) {
-				case 's':
-					dolink &= ~(LN_HARD|LN_MIXED);
-					dolink |= LN_SYMBOLIC;
-					break;
-				case 'h':
-					dolink &= ~(LN_SYMBOLIC|LN_MIXED);
-					dolink |= LN_HARD;
-					break;
-				case 'm':
-					dolink &= ~(LN_SYMBOLIC|LN_HARD);
-					dolink |= LN_MIXED;
-					break;
-				case 'a':
-					dolink &= ~LN_RELATIVE;
-					dolink |= LN_ABSOLUTE;
-					break;
-				case 'r':
-					dolink &= ~LN_ABSOLUTE;
-					dolink |= LN_RELATIVE;
-					break;
-				default:
-					errx(1, "%c: invalid link type", *p);
-					/* NOTREACHED */
-				}
+			parse_l_args(optarg);
 			break;
 		case 'M':
 			metafile = optarg;
@@ -299,6 +275,11 @@
 		usage();
 	}
 
+	if ((dolink & LN_CONTENTS) && metafile == NULL) {
+		warnx("-l c requires -M metalog");
+		usage();
+	}
+
 	/*
 	 * Default permissions based on whether we're a directory or not, since
 	 * an +X may mean that we need to set the execute bit.
@@ -427,6 +408,42 @@
 	/* NOTREACHED */
 }
 
+static void
+parse_l_args(const char *p)
+{
+	for (p = optarg; *p != '\0'; p++) {
+		switch (*p) {
+		case 'c':
+			dolink &= ~(LN_SYMBOLIC | LN_HARD | LN_MIXED);
+			dolink |= LN_CONTENTS;
+			break;
+		case 's':
+			dolink &= ~(LN_CONTENTS | LN_HARD | LN_MIXED);
+			dolink |= LN_SYMBOLIC;
+			break;
+		case 'h':
+			dolink &= ~(LN_CONTENTS | LN_SYMBOLIC | LN_MIXED);
+			dolink |= LN_HARD;
+			break;
+		case 'm':
+			dolink &= ~(LN_CONTENTS | LN_SYMBOLIC | LN_HARD);
+			dolink |= LN_MIXED;
+			break;
+		case 'a':
+			dolink &= ~LN_RELATIVE;
+			dolink |= LN_ABSOLUTE;
+			break;
+		case 'r':
+			dolink &= ~LN_ABSOLUTE;
+			dolink |= LN_RELATIVE;
+			break;
+		default:
+			errx(1, "%c: invalid link type", *p);
+			/* NOTREACHED */
+		}
+	}
+}
+
 static char *
 digest_file(const char *name)
 {
@@ -673,7 +690,25 @@
 	const char *base, *dir;
 	struct stat to_sb;
 
-	/* Try hard links first. */
+	/* First check for mtree contents reference. */
+	if (dolink & LN_CONTENTS) {
+		struct stat from_sb;
+		char *dres;
+
+		if (dolink & LN_RELATIVE)
+			errx(EX_OSERR, "relative contents not yet supported");
+		if (stat(from_name, &from_sb))
+			err(EX_OSERR, "%s: stat", from_name);
+		if (realpath(from_name, src) == NULL)
+			err(EX_OSERR, "%s: realpath", from_name);
+		dres = digest_file(from_name);
+		metadata_log(to_name, "file", NULL, NULL, dres,
+		    from_sb.st_size, src);
+		free(dres);
+		return;
+	}
+
+	/* Try hard links next. */
 	if (dolink & (LN_HARD|LN_MIXED)) {
 		if (do_link(from_name, to_name, target_sb) == -1) {
 			if ((dolink & LN_HARD) || errno != EXDEV)
@@ -709,7 +744,7 @@
 					fflags = NULL;
 				dres = digest_file(from_name);
 				metadata_log(to_name, "file", NULL, NULL,
-				    dres, to_sb.st_size);
+				    dres, to_sb.st_size, NULL);
 				free(dres);
 				mode = omode;
 				owner = oowner;
@@ -727,7 +762,7 @@
 			err(EX_OSERR, "%s: realpath", from_name);
 		do_symlink(src, to_name, target_sb);
 		/* XXX: src may point outside of destdir */
-		metadata_log(to_name, "link", NULL, src, NULL, 0);
+		metadata_log(to_name, "link", NULL, src, NULL, 0, NULL);
 		return;
 	}
 
@@ -736,7 +771,8 @@
 			/* this is already a relative link */
 			do_symlink(from_name, to_name, target_sb);
 			/* XXX: from_name may point outside of destdir. */
-			metadata_log(to_name, "link", NULL, from_name, NULL, 0);
+			metadata_log(to_name, "link", NULL, from_name, NULL, 0,
+			    NULL);
 			return;
 		}
 
@@ -797,7 +833,7 @@
 
 		do_symlink(lnk, to_name, target_sb);
 		/* XXX: Link may point outside of destdir. */
-		metadata_log(to_name, "link", NULL, lnk, NULL, 0);
+		metadata_log(to_name, "link", NULL, lnk, NULL, 0, NULL);
 		return;
 	}
 
@@ -807,7 +843,7 @@
 	 */
 	do_symlink(from_name, to_name, target_sb);
 	/* XXX: from_name may point outside of destdir. */
-	metadata_log(to_name, "link", NULL, from_name, NULL, 0);
+	metadata_log(to_name, "link", NULL, from_name, NULL, 0, NULL);
 }
 
 /*
@@ -1084,7 +1120,8 @@
 	if (!devnull)
 		(void)close(from_fd);
 
-	metadata_log(to_name, "file", tsb, NULL, digestresult, to_sb.st_size);
+	metadata_log(to_name, "file", tsb, NULL, digestresult, to_sb.st_size,
+	    NULL);
 	free(digestresult);
 }
 
@@ -1392,7 +1429,7 @@
 		if (chmod(path, mode))
 			warn("chmod %o %s", mode, path);
 	}
-	metadata_log(path, "dir", NULL, NULL, NULL, 0);
+	metadata_log(path, "dir", NULL, NULL, NULL, 0, NULL);
 }
 
 /*
@@ -1403,7 +1440,8 @@
  */
 static void
 metadata_log(const char *path, const char *type, struct timespec *ts,
-	const char *slink, const char *digestresult, off_t size)
+    const char *slink, const char *digestresult, off_t size,
+    const char *contents)
 {
 	static const char extra[] = { ' ', '\t', '\n', '\\', '#', '\0' };
 	const char *p;
@@ -1413,10 +1451,12 @@
 
 	if (!metafp)	
 		return;
-	/* Buffer for strsnvis(3), used for both path and slink. */
+	/* Buffer for strsnvis(3), used for path, slink, and contents. */
 	buflen = strlen(path);
 	if (slink && strlen(slink) > buflen)
 		buflen = strlen(slink);
+	if (contents && strlen(contents) > buflen)
+		buflen = strlen(contents);
 	buflen = 4 * buflen + 1;
 	if ((buf = malloc(buflen)) == NULL) {
 		warn(NULL);
@@ -1469,6 +1509,10 @@
 		strsnvis(buf, buflen, slink, VIS_CSTYLE, extra);
 		fprintf(metafp, " link=%s", buf);
 	}
+	if (contents) {
+		strsnvis(buf, buflen, contents, VIS_OCTAL, extra);
+		fprintf(metafp, " contents=%s", buf);
+	}
 	if (*type == 'f') /* type=file */
 		fprintf(metafp, " size=%llu", (unsigned long long)size);
 	if (ts != NULL && dopreserve)