Make apm(8) report apmd(8) failure

apm(8) never got the result of the requested power action carried out by
apmd(8), so apm(4) errors got silently discarded;  for example, zzz(8)
would merely print "Suspending system..." and exit zero on platforms
lacking suspend/resume support.

Enrich reply messages from apmd to apm with an error field containing the
failed ioctl(2)'s errno if need be.

Hoist apmd's power action dispatch into handle_client() so it can write the
error in the first place before replying.

OK dv

4 files changed, 61 insertions, 28 deletions

diff --git a/usr.sbin/apm/apm.c b/usr.sbin/apm/apm.c
index c91b8da9ba9..f8962969795 100644
--- a/usr.sbin/apm/apm.c
+++ b/usr.sbin/apm/apm.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: apm.c,v 1.37 2020/09/23 05:50:26 jca Exp $	*/
+/*	$OpenBSD: apm.c,v 1.38 2021/04/06 20:30:32 kn Exp $	*/
 
 /*
  *  Copyright (c) 1996 John T. Kohl
@@ -97,6 +97,7 @@ do_zzz(int fd, enum apm_action action)
 	struct apm_command command;
 	struct apm_reply reply;
 	char *msg;
+	int ret;
 
 	switch (action) {
 	case NONE:
@@ -117,7 +118,10 @@ do_zzz(int fd, enum apm_action action)
 	}
 
 	printf("%s...\n", msg);
-	exit(send_command(fd, &command, &reply));
+	ret = send_command(fd, &command, &reply);
+	if (reply.error)
+		errx(1, "%s: %s", apm_state(reply.newstate), strerror(reply.error));
+	exit(ret);
 }
 
 static int
@@ -418,5 +422,7 @@ balony:
 	default:
 		break;
 	}
+	if (reply.error)
+		errx(1, "%s: %s", apm_state(reply.newstate), strerror(reply.error));
 	return (0);
 }
diff --git a/usr.sbin/apmd/apm-proto.h b/usr.sbin/apmd/apm-proto.h
index 4d54947fe85..dd8cb56991a 100644
--- a/usr.sbin/apmd/apm-proto.h
+++ b/usr.sbin/apmd/apm-proto.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: apm-proto.h,v 1.10 2020/09/23 05:50:26 jca Exp $	*/
+/*	$OpenBSD: apm-proto.h,v 1.11 2021/04/06 20:30:32 kn Exp $	*/
 
 /*
  *  Copyright (c) 1996 John T. Kohl
@@ -64,6 +64,7 @@ struct apm_reply {
 	enum apm_perfmode perfmode;
 	int cpuspeed;
 	struct apm_power_info batterystate;
+	int error;
 };
 
 #define APMD_VNO	3
@@ -71,3 +72,4 @@ struct apm_reply {
 extern const char *battstate(int state);
 extern const char *ac_state(int state);
 extern const char *perf_mode(int mode);
+extern const char *apm_state(int apm_state);
diff --git a/usr.sbin/apmd/apmd.c b/usr.sbin/apmd/apmd.c
index 58026f7a72b..a17dc717dd4 100644
--- a/usr.sbin/apmd/apmd.c
+++ b/usr.sbin/apmd/apmd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: apmd.c,v 1.102 2021/03/25 20:46:55 kn Exp $	*/
+/*	$OpenBSD: apmd.c,v 1.103 2021/04/06 20:30:32 kn Exp $	*/
 
 /*
  *  Copyright (c) 1995, 1996 John T. Kohl
@@ -65,9 +65,9 @@ void usage(void);
 int power_status(int fd, int force, struct apm_power_info *pinfo);
 int bind_socket(const char *sn);
 enum apm_state handle_client(int sock_fd, int ctl_fd);
-void suspend(int ctl_fd);
-void stand_by(int ctl_fd);
-void hibernate(int ctl_fd);
+int suspend(int ctl_fd);
+int stand_by(int ctl_fd);
+int hibernate(int ctl_fd);
 void resumed(int ctl_fd);
 void setperfpolicy(char *policy);
 void sigexit(int signo);
@@ -266,16 +266,23 @@ handle_client(int sock_fd, int ctl_fd)
 		return NORMAL;
 	}
 
+	bzero(&reply, sizeof(reply));
 	power_status(ctl_fd, 0, &reply.batterystate);
 	switch (cmd.action) {
 	case SUSPEND:
 		reply.newstate = SUSPENDING;
+		if (suspend(ctl_fd) == -1)
+			reply.error = errno;
 		break;
 	case STANDBY:
 		reply.newstate = STANDING_BY;
+		if (stand_by(ctl_fd) == -1)
+			reply.error = errno;
 		break;
 	case HIBERNATE:
 		reply.newstate = HIBERNATING;
+		if (hibernate(ctl_fd) == -1)
+			reply.error = errno;
 		break;
 	case SETPERF_LOW:
 		reply.newstate = NORMAL;
@@ -321,40 +328,49 @@ handle_client(int sock_fd, int ctl_fd)
 	return reply.newstate;
 }
 
-void
+int
 suspend(int ctl_fd)
 {
+	int ret;
+
 	logmsg(LOG_NOTICE, "system suspending");
 	power_status(ctl_fd, 1, NULL);
 	do_etc_file(_PATH_APM_ETC_SUSPEND);
 	sync();
 	sleep(1);
-	if (ioctl(ctl_fd, APM_IOC_SUSPEND, 0) == -1)
+	if ((ret = ioctl(ctl_fd, APM_IOC_SUSPEND, 0)) == -1)
 		logmsg(LOG_WARNING, "%s: %s", __func__, strerror(errno));
+	return (ret);
 }
 
-void
+int
 stand_by(int ctl_fd)
 {
+	int ret;
+
 	logmsg(LOG_NOTICE, "system entering standby");
 	power_status(ctl_fd, 1, NULL);
 	do_etc_file(_PATH_APM_ETC_STANDBY);
 	sync();
 	sleep(1);
-	if (ioctl(ctl_fd, APM_IOC_STANDBY, 0) == -1)
+	if ((ret = ioctl(ctl_fd, APM_IOC_STANDBY, 0)) == -1)
 		logmsg(LOG_WARNING, "%s: %s", __func__, strerror(errno));
+	return (ret);
 }
 
-void
+int
 hibernate(int ctl_fd)
 {
+	int ret;
+
 	logmsg(LOG_NOTICE, "system hibernating");
 	power_status(ctl_fd, 1, NULL);
 	do_etc_file(_PATH_APM_ETC_HIBERNATE);
 	sync();
 	sleep(1);
-	if (ioctl(ctl_fd, APM_IOC_HIBERNATE, 0) == -1)
+	if ((ret = ioctl(ctl_fd, APM_IOC_HIBERNATE, 0)) == -1)
 		logmsg(LOG_WARNING, "%s: %s", __func__, strerror(errno));
+	return (ret);
 }
 
 void
@@ -512,20 +528,12 @@ main(int argc, char *argv[])
 			break;
 
 		if (rv == 1 && ev->ident == sock_fd) {
-			switch (handle_client(sock_fd, ctl_fd)) {
-			case NORMAL:
-				break;
-			case SUSPENDING:
-				suspend(ctl_fd);
-				break;
-			case STANDING_BY:
-				stand_by(ctl_fd);
-				break;
-			case HIBERNATING:
-				hibernate(ctl_fd);
-				break;
-			}
-			continue;
+			int state;
+
+			if ((state = handle_client(sock_fd, ctl_fd)) == -1)
+				logmsg(LOG_WARNING, "%s: %s", apm_state(state), strerror(errno));
+			else
+				continue;
 		}
 
 		suspends = standbys = hibernates = resumes = 0;
diff --git a/usr.sbin/apmd/apmsubr.c b/usr.sbin/apmd/apmsubr.c
index 9a8232e498f..63b72da1406 100644
--- a/usr.sbin/apmd/apmsubr.c
+++ b/usr.sbin/apmd/apmsubr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: apmsubr.c,v 1.9 2020/09/23 05:50:26 jca Exp $	*/
+/*	$OpenBSD: apmsubr.c,v 1.10 2021/04/06 20:30:32 kn Exp $	*/
 
 /*
  *  Copyright (c) 1995,1996 John T. Kohl
@@ -83,3 +83,20 @@ perf_mode(int mode)
 		return "invalid";
 	}
 }
+
+const char *
+apm_state(int apm_state)
+{
+	switch (apm_state) {
+	case NORMAL:
+		return "normal";
+	case SUSPENDING:
+		return "suspend";
+	case STANDING_BY:
+		return "standby";
+	case HIBERNATING:
+		return "hibenate";
+	default:
+		return "unknown";
+}
+}