2019-09-24 16:45:55

by NeilBrown

[permalink] [raw]
Subject: [PATCH 2/3] conffile: allow optional include files.

If nfs.conf contains, for example
include = /etc/nfs.conf.local
and /etc/nfs.conf.local doesn't exist, then a warning is given.
Sometimes it is useful to have an optional include file which is
included if present, but for which an absence doesn't give a
warning.

Systemd has a convention that a hyphen at the start of
an include file name marks it as optional, so add this convention
to nfs-utils.
So
include = -/etc/nfs.conf.local
will not give a warning if the file doesn't exist.

Signed-off-by: NeilBrown <[email protected]>
---
support/nfs/conffile.c | 13 ++++++++++---
systemd/nfs.conf.man | 3 +++
2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/support/nfs/conffile.c b/support/nfs/conffile.c
index 6ba8a35ce7c6..d55bfe10120a 100644
--- a/support/nfs/conffile.c
+++ b/support/nfs/conffile.c
@@ -412,11 +412,18 @@ conf_parse_line(int trans, char *line, const char *filename, int lineno, char **

if (strcasecmp(line, "include")==0) {
/* load and parse subordinate config files */
+ _Bool optional = false;
+
+ if (val && *val == '-') {
+ optional = true;
+ val++;
+ }
+
relpath = relative_path(filename, val);
if (relpath == NULL) {
- xlog_warn("config error at %s:%d: "
- "error loading included config",
- filename, lineno);
+ if (!optional)
+ xlog_warn("config error at %s:%d: error loading included config",
+ filename, lineno);
return;
}

diff --git a/systemd/nfs.conf.man b/systemd/nfs.conf.man
index d375bcc1d5a7..3f1c7261991d 100644
--- a/systemd/nfs.conf.man
+++ b/systemd/nfs.conf.man
@@ -65,6 +65,9 @@ section headers, then new sections will be created just as if the
included file appeared in place of the
.B include
line.
+If the file name starts with a hyphen then that is stripped off
+before the file is opened, and if file doesn't exist no warning is
+given. Normally a non-existent include file generates a warning.
.PP
Lookup of section and value names is case-insensitive.