duration parsing

2 files changed, 38 insertions, 7 deletions

diff --git a/README.md b/README.md
index 7b1bd20..d5e86d1 100644
--- a/README.md
+++ b/README.md
@@ -61,6 +61,9 @@ Over uschedule:
 * `-R`: add between 0 and RANDDELAY seconds to the scheduled time.
 * `-s`: commands are executed even if they are SLACK (default: 60) seconds late.
 
+The durations RANDDELAY and SLACK and TIMEWAIT are parsed as seconds,
+unless a postfix of `m` for minutes, `h` for hours, or `d` for days is used.
+
 The remaining arguments are patterns for the time fields:
 
 * `-d`: day of month
@@ -99,7 +102,7 @@ of TIMEFILE plus TIMEWAIT seconds.
 
 When `-T` is *not* passed, snooze will start finding the first matching time
 starting from the mtime of TIMEFILE, and taking SLACK into account.
-(E.g. `-H0 -s$((24*60*60)) -t timefile` will start an instant
+(E.g. `-H0 -s 1d -t timefile` will start an instant
 execution when timefile has not been touched today, whereas without `-t`
 this would always wait until next midnight.)
 
@@ -136,15 +139,15 @@ Run a job like cron, every day at 7am and 7pm:
 
 Run a job daily, never twice a day:
 
-	exec snooze -H0 -s $((24*60*60)) -t timefile \
+	exec snooze -H0 -s 1d -t timefile \
 		sh -c 'run-parts /etc/cron.daily; touch timefile'
 
 Use snooze inline, run a mirror script every hour at 30 minutes past,
 but ensure there are at least 20 minutes in between.
 
 	set -e
-	snooze -H'*' -M30 -t timefile -T $((20*60))
-	touch timefile  # remove this if instantly retrying on failure is ok
+	snooze -H'*' -M30 -t timefile -T 20m
+	touch timefile  # remove this if instantly retrying on failure were ok
 	mirrorallthethings
 	touch timefile
 
diff --git a/snooze.c b/snooze.c
index a5df967..d7dd67e 100644
--- a/snooze.c
+++ b/snooze.c
@@ -64,6 +64,34 @@ parse_int(char **s, size_t minn, size_t maxn)
 	return n;
 }
 
+static long
+parse_dur(char *s)
+{
+	long n;
+	char *end;
+
+	errno = 0;
+	n = strtol(s, &end, 10);
+	if (errno) {
+		perror("strtol");
+		exit(1);
+	}
+	if (n < 0) {
+		fprintf(stderr, "negative duration\n");
+		exit(1);
+	}
+	switch (*end) {
+	case 'm': n *= 60; break;
+	case 'h': n *= 60*60; break;
+	case 'd': n *= 24*60*60; break;
+	case 0: break;
+	default:
+		fprintf(stderr, "junk after duration: %s\n", end);
+		exit(1);
+	}
+	return n;
+}
+
 static int
 parse(char *expr, char *buf, long bufsiz, int offset)
 {
@@ -229,10 +257,10 @@ int main(int argc, char *argv[])
 			break;
 		case 'n': nflag++; break;
 		case 'v': vflag++; break;
-		case 's': slack = atoi(optarg); break;
-		case 'T': timewait = atoi(optarg); break;
+		case 's': slack = parse_dur(optarg); break;
+		case 'T': timewait = parse_dur(optarg); break;
 		case 't': timefile = optarg; break;
-		case 'R': randdelay = atoi(optarg); break;
+		case 'R': randdelay = parse_dur(optarg); break;
 		default:
                         fprintf(stderr, "Usage: %s [-nv] [-t timefile] [-T timewait] [-R randdelay] [-s slack]\n"
 			    "  [-d mday] [-m mon] [-w wday] [-D yday] [-W yweek] [-H hour] [-M min] [-S sec] COMMAND...\n"