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.

initctl.c

@@ -28,6 +28,7 @@
 #include <sys/un.h>
 
 #include "finit.h"
+#include "cond.h"
 #include "helpers.h"
 #include "service.h"
 
@@ -107,26 +108,78 @@ static int do_svc(int cmd, char *arg)
 		.cmd = cmd,
 	};
 
-	if (!arg || !arg[0]) {
-		if (cmd == INIT_CMD_RELOAD_SVC) {
-			rq.cmd = INIT_CMD_RELOAD;
-			goto exit;
-		}
-
-		return 1;
-	}
 	strlcpy(rq.data, arg, sizeof(rq.data));
 
-exit:
 	return do_send(&rq, sizeof(rq));
 }
 
 static int do_emit   (char *arg) { return do_svc(INIT_CMD_EMIT,        arg); }
+static int do_reload (char *arg) { return do_svc(INIT_CMD_RELOAD,      arg); }
 static int do_start  (char *arg) { return do_svc(INIT_CMD_START_SVC,   arg); }
 static int do_stop   (char *arg) { return do_svc(INIT_CMD_STOP_SVC,    arg); }
-static int do_reload (char *arg) { return do_svc(INIT_CMD_RELOAD_SVC,  arg); }
 static int do_restart(char *arg) { return do_svc(INIT_CMD_RESTART_SVC, arg); }
 
+static void show_cond_one(const char *_conds)
+{
+	static char conds[MAX_ARG_LEN];
+	char *cond;
+
+	strlcpy(conds, _conds, sizeof(conds));
+
+	putchar('<');
+
+	for (cond = strtok(conds, ","); cond; cond = strtok(NULL, ",")) {
+		if (cond != conds)
+			putchar(',');
+
+		switch (cond_get(cond)) {
+		case COND_ON:
+			printf("+%s", cond);
+			break;
+		case COND_FLUX:
+			printf("\e[1m~%s\e[0m", cond);
+			break;
+		case COND_OFF:
+			printf("\e[1m-%s\e[0m", cond);
+			break;
+		}
+	}
+
+	putchar('>');
+}
+
+static void show_cond(void)
+{
+	enum cond_state cond;
+	svc_t *svc;
+
+	printf("PID     Service               Status  Condition (+ on, ~ flux, - off)\n");
+	printf("====================================================================================\n");
+
+	for (svc = svc_iterator(1); svc; svc = svc_iterator(0)) {
+		if (!svc->cond[0])
+			continue;
+
+		cond = cond_get_agg(svc->cond);
+
+		printf("%-6d  %-20.20s  ", svc->pid, svc->cmd);
+
+		if (cond == COND_ON)
+			printf("%-6.6s  ", condstr(cond));
+		else
+			printf("\e[1m%-6.6s\e[0m  ", condstr(cond));
+
+		show_cond_one(svc->cond);
+		putchar('\n');
+	}
+}
+
+static int do_cond(char *arg)
+{
+	show_cond();
+	return 0;
+}
+
 static int show_version(char *UNUSED(arg))
 {
 	puts("v" VERSION);
@@ -250,12 +303,10 @@ static int usage(int rc)
 		"  reload                    Reload *.conf in /etc/finit.d/ and activate changes\n"
 		"  runlevel [0-9]            Show or set runlevel: 0 halt, 6 reboot\n"
 		"  status | show             Show status of services\n"
+		"  cond     show             Show condition status\n"
 		"  start    <JOB|NAME>[:ID]  Start service by job# or name, with optional ID\n"
 		"  stop     <JOB|NAME>[:ID]  Stop/Pause a running service by job# or name\n"
 		"  restart  <JOB|NAME>[:ID]  Restart (stop/start) service by job# or name\n"
-		"  reload   <JOB|NAME>[:ID]  Reload (SIGHUP) service by job# or name\n"
-		"  status   <JOB|NAME>[:ID]  Show status of a service by job# or name\n"
-		"  show     <JOB|NAME>[:ID]  Alias to 'status <JOB|NAME>[:ID]'\n"
 		"  version                   Show Finit version\n\n", __progname);
 
 	return rc;
@@ -271,6 +322,7 @@ int main(int argc, char *argv[])
 		{ "runlevel", do_runlevel  },
 		{ "status",   show_status  },
 		{ "show",     show_status  }, /* Convenience alias */
+		{ "cond",     do_cond      },
 		{ "start",    do_start     },
 		{ "stop",     do_stop      },
 		{ "restart",  do_restart   },