commit 9fcd8f801b6aa575dbd5decff531007162269445
Author: Kerin Millar <kfm@plushkava.net>
Date:   Tue Jan 5 23:04:09 2021 +0000

    Raise useful warnings in the case that ulimit fails
    
    Unfortunately, the means by which OpenRC allows for the configuration of
    resource limits is intrinsically non-portable. POSIX sh is only
    obligated to support the -f option. Consequently, any implemented
    extensions are prone to vary considerably. Further, popular
    implementations such as dash don't even necessarily allow for multiple
    option/value pairs.  A better approach would be to use setrlimit(2).
    
    For now, try to raise meaningful warnings in the event of failure. This
    is accomplished by stashing the effective value of rc_ulimit both after
    importing the global config files and after importing any config files
    specific to the service. After ulimit is invoked, the exit status is
    checked. In the case that it has failed, a warning message is emitted
    which reports the sh implementation and the options that were given
    (because the shell might not report them). It also suggests that the
    configuration files most likely to be responsible for the issue be
    edited and advises the user of the service name, where appropriate.

diff --git a/sh/openrc-run.sh.in b/sh/openrc-run.sh.in
index 7e9064c2..7778f4ee 100644
--- a/sh/openrc-run.sh.in
+++ b/sh/openrc-run.sh.in
@@ -220,6 +220,10 @@ if [ -d "@SYSCONFDIR@/rc.conf.d" ]; then
 	done
 fi
 
+# Stash the globally defined rc_ulimit value so that we may later determine
+# whether it was overridden by a service conf.d file.
+_global_rc_ulimit=${rc_ulimit:-$RC_ULIMIT}
+
 _conf_d=${RC_SERVICE%/*}/../conf.d
 # If we're net.eth0 or openvpn.work then load net or openvpn config
 _c=${RC_SVCNAME%%.*}
@@ -236,6 +240,10 @@ if ! sourcex -e "$_conf_d/$RC_SVCNAME.$RC_RUNLEVEL"; then
 fi
 unset _conf_d
 
+# Stash the rc_ulimit value defined in conf.d scope so that we may later
+# determine whether the global value was overriden.
+_local_rc_ulimit=${rc_ulimit:-$RC_ULIMIT}
+
 # load service supervisor functions
 sourcex "@LIBEXECDIR@/sh/runit.sh"
 sourcex "@LIBEXECDIR@/sh/s6.sh"
@@ -253,9 +261,24 @@ fi
 
 for _cmd; do
 	if [ "$_cmd" != status -a "$_cmd" != describe ]; then
-		# Apply any ulimit defined
-		[ -n "${rc_ulimit:-$RC_ULIMIT}" ] && \
-			ulimit ${rc_ulimit:-$RC_ULIMIT}
+		# Apply any ulimit defined. Unfortunately, this approach is
+		# intrinsically non-portable. POSIX sh is only obligated to
+		# support the -f option. Consequently, any implemented
+		# extensions are prone to vary considerably. Further, popular
+		# implementations such as dash don't even necessarily allow for
+		# multiple option/value pairs.  A better approach would be to
+		# use setrlimit(2). For now, try to raise meaningful warnings
+		# in the event of failure.
+		if [ -n "${rc_ulimit:=$RC_ULIMIT}" ] && ! ulimit ${rc_ulimit}; then
+			_sh=$(readlink /bin/sh 2>/dev/null) || _sh=sh
+			ewarn "Your /bin/sh implementation ($_sh) failed to apply these rc_limit options: $rc_ulimit"
+			if [ "$_global_rc_ulimit" = "$_local_rc_ulimit" ]; then
+				ewarn "Please check your /etc/rc.conf and /etc/rc.conf.d files and adjust as necessary."
+			else
+				ewarn "Please check the conf.d file(s) for $RC_SVCNAME and adjust as necessary."
+			fi
+		fi
+		unset _sh _global_rc_ulimit _local_rc_ulimit
 		# Apply cgroups settings if defined
 		if [ "$(command -v cgroup_add_service)" = "cgroup_add_service" ]
 		then