procd: add initial implementation

procd is the new OpenWrt process management daemon. It keeps track of processes
started from init scripts (via ubus calls), and can suppress redundant service
start/restart requests when the config/environment has not changed.

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@34865 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 171 insertions, 0 deletions

diff --git a/package/procd/files/procd.sh b/package/procd/files/procd.sh
new file mode 100644
index 0000000000..e771e0c156
--- /dev/null
+++ b/package/procd/files/procd.sh
@@ -0,0 +1,171 @@
+# procd API:
+#
+# procd_open_service(name, [script]):
+#   Initialize a new procd command message containing a service with one or more instances
+#
+# procd_close_service()
+#   Send the command message for the service
+#
+# procd_open_instance([name]):
+#   Add an instance to the service described by the previous procd_open_service call
+#
+# procd_set_param(type, [value...])
+#   Available types:
+#     command: command line (array).
+#     env: environment variable (passed to the process)
+#     data: arbitrary name/value pairs for detecting config changes (table)
+#     file: configuration files (array)
+#     netdev: bound network device (detects ifindex changes)
+#
+#   No space separation is done for arrays/tables - use one function argument per command line argument
+#
+# procd_close_instance():
+#   Complete the instance being prepared
+#
+# procd_kill(service, [instance]):
+#   Kill a service instance (or all instances)
+#
+
+. $IPKG_INSTROOT/usr/share/libubox/jshn.sh
+
+_PROCD_SERVICE=
+
+_procd_call() {
+	local old_cb
+
+	json_set_namespace procd old_cb
+	"$@"
+	json_set_namespace $old_cb
+}
+
+_procd_wrapper() {
+	while [ -n "$1" ]; do
+		eval "$1() { _procd_call _$1 \"\$@\"; }"
+		shift
+	done
+}
+
+_procd_ubus_call() {
+	local cmd="$1"
+
+	ubus call service "$cmd" "$(json_dump)"
+	json_cleanup
+}
+
+_procd_open_service() {
+	local name="$1"
+	local script="$2"
+
+	_PROCD_SERVICE="$name"
+	_PROCD_INSTANCE_SEQ=0
+
+	json_init
+	json_add_string name "$name"
+	[ -n "$script" ] && json_add_string script "$script"
+	json_add_object instances
+}
+
+_procd_close_service() {
+	json_close_object
+	_procd_ubus_call set
+}
+
+_procd_add_array_data() {
+	while [ -n "$1" ]; do
+		json_add_string "" "$1"
+		shift
+	done
+}
+
+_procd_add_array() {
+	json_add_array "$1"
+	shift
+	_procd_add_array_data "$@"
+	json_close_array
+}
+
+_procd_add_table_data() {
+	while [ -n "$1" ]; do
+		local var="${1%%=*}"
+		local val="${1#*=}"
+		[[ "$1" == "$val" ]] && val=
+		json_add_string "$var" "$val"
+		shift
+	done
+}
+
+_procd_add_table() {
+	json_add_object "$1"
+	shift
+	_procd_add_table_data "$@"
+	json_close_object
+}
+
+_procd_open_instance() {
+	local name="$1"; shift
+
+	_PROCD_INSTANCE_SEQ="$(($_PROCD_INSTANCE_SEQ + 1))"
+	name="${name:-instance$_PROCD_INSTANCE_SEQ}"
+	json_add_object "$name"
+}
+
+_procd_set_param() {
+	local type="$1"; shift
+
+	case "$type" in
+		env|data)
+			_procd_add_table "$type" "$@"
+		;;
+		command|netdev|file)
+			_procd_add_array "$type" "$@"
+		;;
+		nice)
+			json_add_int "$type" "$1"
+		;;
+	esac
+}
+
+_procd_append_param() {
+	local type="$1"; shift
+
+	json_select "$type"
+	case "$type" in
+		env|data)
+			_procd_add_table_data "$@"
+		;;
+		command|netdev|file)
+			_procd_add_array_data "$@"
+		;;
+	esac
+	json_select ..
+}
+
+_procd_close_instance() {
+	json_close_object
+}
+
+_procd_add_instance() {
+	_procd_open_instance
+	_procd_set_command "$@"
+	_procd_close_instance
+}
+
+_procd_kill() {
+	local service="$1"
+	local instance="$2"
+
+	json_init
+	[ -n "$service" ] && json_add_string service "$service"
+	[ -n "$instance" ] && json_add_string instance "$instance"
+	_procd_ubus_call delete
+}
+
+_procd_wrapper \
+	procd_open_service \
+	procd_close_service \
+	procd_add_instance \
+	procd_open_instance \
+	procd_close_instance \
+	procd_set_param \
+	procd_append_param \
+	procd_kill