apcsmart: CS "hack" updates

This patch adds cshdelay option (with default set to 3.5s) between
"simulate power failure" and "soft hibernate" commands.

docs/man/apcsmart.txt

@@ -146,6 +146,10 @@ behaviour quite a bit, depending on the model.
     Immediately before issuing *S*, "simulate power failure" is issued. The
     remaining behaviour is as in *S* case.
 +
+There's a delay between "simulate power failure" and *S* - by default set to
+3.5s. You can control it through *cshdelay* option (allowed values are from 0
+to 9.9).
++
 The name came from APC CS models, where such trick was used to power down
 UPSes in consistent fashion using only *S*. It\'s better to use *@nnn*
 command if your UPS supports it (and is not too old, see below).

drivers/apcsmart.c

@@ -1441,10 +1441,14 @@ static int sdcmd_S(const void *foo)
 /* soft hibernate, hack version for CS 350 & co. */
 static int sdcmd_CS(const void *foo)
 {
-	int ret;
+	int ret, cshd = 3500000;
 	char temp[APC_SBUF];
+	const char *val;
+
+	if ((val = getval("cshdelay")))
+		cshd = (int)(strtod(val, NULL) * 1000000);
 
-	debx(1, "issuing CS 'hack' [%s+%s]", prtchr(APC_CMD_SIMPWF), prtchr(APC_CMD_SOFTDOWN));
+	debx(1, "issuing CS 'hack' [%s+%s] with %2.1f sec delay", prtchr(APC_CMD_SIMPWF), prtchr(APC_CMD_SOFTDOWN), (double)cshd / 1000000);
 	if (ups_status & APC_STAT_OL) {
 		apc_flush(0);
 		debx(1, "issuing [%s]", prtchr(APC_CMD_SIMPWF));
@@ -1457,6 +1461,7 @@ static int sdcmd_CS(const void *foo)
 		if (ret < 0) {
 			return STAT_INSTCMD_FAILED;
 		}
+		usleep(cshd);
 	}
 	/* continue with regular soft hibernate */
 	return sdcmd_S((void *)1);
@@ -2000,6 +2005,7 @@ void upsdrv_makevartable(void)
 	addvar(VAR_VALUE, "awd", "hard hibernate's additional wakeup delay");
 	addvar(VAR_VALUE, "sdtype", "simple shutdown method");
 	addvar(VAR_VALUE, "advorder", "advanced shutdown control");
+	addvar(VAR_VALUE, "cshdelay", "CS hack delay");
 }
 
 void upsdrv_help(void)
@@ -2031,6 +2037,11 @@ void upsdrv_initups(void)
 			fatalx(EXIT_FAILURE, "invalid value (%s) for option 'advorder'", val);
 	}
 
+	/* sanitize cshdelay */
+	if ((val = getval("cshdelay")) && !rexhlp(APC_CSHDFMT, val)) {
+			fatalx(EXIT_FAILURE, "invalid value (%s) for option 'cshdelay'", val);
+	}
+
 	upsfd = extrafd = ser_open(device_path);
 	apc_ser_set();
 

drivers/apcsmart.h

@@ -161,6 +161,9 @@
 /* advorder method regex format*/
 #define APC_ADVFMT	"^([0-4]{1,5}|[Nn][Oo])$"
 
+/* cshdelay format */
+#define APC_CSHDFMT	"^([0-9]\\.?|[0-9]?\\.[0-9])$"
+
 /* error logging/debug related macros */
 
 #define fatx(fmt, ...) fatalx(EXIT_FAILURE, "%s: " fmt, __func__ , ## __VA_ARGS__)