Dynamically manage service states based on user defined conditions

Old event system has been replaced with a more generic condition
concept. The idea is that finit plugins may provide arbitrary
conditions that services may specify as dependencies that they require
to run.

In order to accomodate this, the service management has been
redesigned to use a state machine.

api.c

@@ -32,6 +32,7 @@
 
 #include "config.h"
 #include "finit.h"
+#include "cond.h"
 #include "conf.h"
 #include "helpers.h"
 #include "plugin.h"
@@ -46,7 +47,7 @@ uev_t api_watcher;
 /* Allowed characters in job/id/name */
 static int isallowed(int ch)
 {
-	return isalnum(ch) || isspace(ch) || ch == ':';
+	return isprint(ch);
 }
 
 /* Sanitize user input, make sure to NUL terminate. */
@@ -113,14 +114,29 @@ static int call(int (*action)(svc_t *), char *buf, size_t len)
 	return result;
 }
 
-static int service_pause(svc_t *svc)
+static int service_block(svc_t *svc)
 {
-	return service_stop(svc, SVC_PAUSED_STATE);
+	svc->block = SVC_BLOCK_USER;
+	service_step(svc);
+	return 0;
 }
 
-static int do_start  (char *buf, size_t len) { return call(service_start,   buf, len); }
-static int do_pause  (char *buf, size_t len) { return call(service_pause,   buf, len); }
-static int do_reload (char *buf, size_t len) { return call(service_reload,  buf, len); }
+static int service_unblock(svc_t *svc)
+{
+	svc->block = SVC_BLOCK_NONE;
+	service_step(svc);
+	return 0;
+}
+
+static int service_restart(svc_t *svc)
+{
+	svc->dirty = 1;
+	service_step(svc);
+	return 0;
+}
+
+static int do_start  (char *buf, size_t len) { return call(service_unblock, buf, len); }
+static int do_pause  (char *buf, size_t len) { return call(service_block,   buf, len); }
 static int do_restart(char *buf, size_t len) { return call(service_restart, buf, len); }
 
 #ifndef INETD_DISABLED
@@ -155,9 +171,7 @@ typedef struct {
 } ev_t;
 
 ev_t ev_list[] = {
-	{ "RELOAD", conf_reload_dynamic   },
-	{ "STOP",   service_stop_dynamic  },
-	{ "START",  service_start_dynamic },
+	{ "RELOAD", service_reload_dynamic   },
 	{ NULL, NULL }
 };
 
@@ -175,9 +189,13 @@ static int do_handle_event(char *event)
 		}
 	}
 
-	/* XXX: iterate over all services' events before failing. */
-
-	return -1;
+	if (event[0] == '-')
+		cond_clear(&event[1]);
+	else if (event[0] == '+')
+		cond_set(&event[1]);
+	else
+		cond_set(event);
+	return 0;
 }
 
 static int do_handle_emit(char *buf, size_t len)
@@ -284,10 +302,6 @@ static void cb(uev_t *w, void *UNUSED(arg), int UNUSED(events))
 			result = do_pause(rq.data, sizeof(rq.data));
 			break;
 
-		case INIT_CMD_RELOAD_SVC:
-			result = do_reload(rq.data, sizeof(rq.data));
-			break;
-
 		case INIT_CMD_RESTART_SVC:
 			result = do_restart(rq.data, sizeof(rq.data));
 			break;