[PATCH] Add mount -P to hide pseudo filesystems

[David Wilson <dw@botanicus.net>]

This is just shorthand for an increasingly necessary yet cumbersome and
error-prone "grep -v" pipe. The alternative was to extend -t to accept
"nopseudofs", but that is tougher on the fingers.
---
 sys-utils/mount.8 |  4 ++++
 sys-utils/mount.c | 17 +++++++++++++----
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/sys-utils/mount.8 b/sys-utils/mount.8
index 004a513..311b514 100644
--- a/sys-utils/mount.8
+++ b/sys-utils/mount.8
@@ -663,6 +663,10 @@ sections.
 .RE
 
 .TP
+.BR \-P , " \-\-no\-pseudofs"
+Inhibit listing of pseudo filesystem mounts. Only mounts backed by a network
+location or block device are displayed.
+.TP
 .BR \-R , " \-\-rbind"
 Remount a subtree and all possible submounts somewhere else (so that its
 contents are available in both places).  See above.
diff --git a/sys-utils/mount.c b/sys-utils/mount.c
index 73f9d0b..17dba9e 100644
--- a/sys-utils/mount.c
+++ b/sys-utils/mount.c
@@ -120,7 +120,8 @@ static void safe_fputs(const char *data)
 	}
 }
 
-static void print_all(struct libmnt_context *cxt, char *pattern, int show_label)
+static void print_all(struct libmnt_context *cxt, char *pattern,
+		      int show_label, int no_pseudofs)
 {
 	struct libmnt_table *tb;
 	struct libmnt_iter *itr = NULL;
@@ -147,6 +148,9 @@ static void print_all(struct libmnt_context *cxt, char *pattern, int show_label)
 
 		if (!mnt_fs_is_pseudofs(fs))
 			xsrc = mnt_pretty_path(src, cache);
+		else if (no_pseudofs)
+			continue;
+
 		printf ("%s on ", xsrc ? xsrc : src);
 		safe_fputs(mnt_fs_get_target(fs));
 
@@ -740,6 +744,7 @@ static void __attribute__((__noreturn__)) usage(FILE *out)
 	fprintf(out, _(
 	" -o, --options <list>    comma-separated list of mount options\n"
 	" -O, --test-opts <list>  limit the set of filesystems (use with -a)\n"
+	" -P, --no-pseudofs       inhibit listing of pseudo filesystems\n"
 	" -r, --read-only         mount the filesystem read-only (same as -o ro)\n"
 	" -t, --types <list>      limit the set of filesystem types\n"));
 	fprintf(out, _(
@@ -792,6 +797,7 @@ static void __attribute__((__noreturn__)) usage(FILE *out)
 int main(int argc, char **argv)
 {
 	int c, rc = MOUNT_EX_SUCCESS, all = 0, show_labels = 0;
+	int no_pseudofs = 0;
 	struct libmnt_context *cxt;
 	struct libmnt_table *fstab = NULL;
 	char *srcbuf = NULL;
@@ -842,6 +848,7 @@ int main(int argc, char **argv)
 		{ "make-rprivate", 0, 0, MOUNT_OPT_RPRIVATE },
 		{ "make-runbindable", 0, 0, MOUNT_OPT_RUNBINDABLE },
 		{ "no-canonicalize", 0, 0, 'c' },
+		{ "no-pseudofs", 0, 0, 'P' },
 		{ "internal-only", 0, 0, 'i' },
 		{ "show-labels", 0, 0, 'l' },
 		{ "target", 1, 0, MOUNT_OPT_TARGET },
@@ -869,12 +876,12 @@ int main(int argc, char **argv)
 
 	mnt_context_set_tables_errcb(cxt, table_parser_errcb);
 
-	while ((c = getopt_long(argc, argv, "aBcfFhilL:Mno:O:rRsU:vVwt:T:",
+	while ((c = getopt_long(argc, argv, "aBcfFhilL:Mno:O:PrRsU:vVwt:T:",
 					longopts, NULL)) != -1) {
 
 		/* only few options are allowed for non-root users */
 		if (mnt_context_is_restricted(cxt) &&
-		    !strchr("hlLUVvrist", c) &&
+		    !strchr("hlLUVvPrist", c) &&
 		    c != MOUNT_OPT_TARGET &&
 		    c != MOUNT_OPT_SOURCE)
 			exit_non_root(option_to_longopt(c, longopts));
@@ -939,6 +946,8 @@ int main(int argc, char **argv)
 		case 'l':
 			show_labels = 1;
 			break;
+		case 'P':
+			no_pseudofs = 1;
 		case 't':
 			types = optarg;
 			break;
@@ -1021,7 +1030,7 @@ int main(int argc, char **argv)
 	    !all) {
 		if (oper || mnt_context_get_options(cxt))
 			usage(stderr);
-		print_all(cxt, types, show_labels);
+		print_all(cxt, types, show_labels, no_pseudofs);
 		goto done;
 	}
 
-- 
2.1.4