util: strtotime: stricter time parsing

as input: an empty string or non-digit characters are digits are considered an
error now. Still, for the format tools output the formatted time string as
time_t 0 on a parse error.

sfeed_frames.c

@@ -105,8 +105,7 @@ static void
 printfeed(FILE *fpitems, FILE *fpin, struct feed *f)
 {
 	char dirpath[PATH_MAX], filepath[PATH_MAX];
-	char *fields[FieldLast], *feedname;
-	char name[128];
+	char *fields[FieldLast], *feedname, name[128];
 	size_t namelen;
 	struct stat st;
 	FILE *fpcontent = NULL;
@@ -177,14 +176,14 @@ printfeed(FILE *fpitems, FILE *fpin, struct feed *f)
 		}
 
 		/* set modified and access time of file to time of item. */
-		r = strtotime(fields[FieldUnixTimestamp], &parsedtime);
-		if (r != -1) {
+		parsedtime = 0;
+		if (strtotime(fields[FieldUnixTimestamp], &parsedtime) != -1) {
 			contenttime.actime = parsedtime;
 			contenttime.modtime = parsedtime;
 			utime(filepath, &contenttime);
 		}
 
-		isnew = (r != -1 && parsedtime >= comparetime) ? 1 : 0;
+		isnew = (parsedtime >= comparetime) ? 1 : 0;
 		totalnew += isnew;
 		f->totalnew += isnew;
 		f->total++;

sfeed_html.c

@@ -20,7 +20,6 @@ printfeed(FILE *fp, struct feed *f)
 	char *fields[FieldLast];
 	time_t parsedtime;
 	unsigned int islink, isnew;
-	int r;
 
 	if (f->name[0] != '\0') {
 		fputs("<h2 id=\"", stdout);
@@ -34,8 +33,10 @@ printfeed(FILE *fp, struct feed *f)
 	fputs("<table cellpadding=\"0\" cellspacing=\"0\">\n", stdout);
 
 	while (parseline(&line, &linesize, fields, fp) > 0) {
-		r = strtotime(fields[FieldUnixTimestamp], &parsedtime);
-		isnew = (r != -1 && parsedtime >= comparetime) ? 1 : 0;
+		parsedtime = 0;
+		strtotime(fields[FieldUnixTimestamp], &parsedtime);
+
+		isnew = (parsedtime >= comparetime) ? 1 : 0;
 		islink = (fields[FieldLink][0] != '\0') ? 1 : 0;
 
 		totalnew += isnew;

sfeed_mbox.c

@@ -81,7 +81,6 @@ printfeed(FILE *fp, const char *feedname)
 	char *fields[FieldLast], timebuf[32], mtimebuf[32];
 	char host[HOST_NAME_MAX + 1], *user;
 	time_t parsedtime;
-	int r;
 
 	if (!(user = getenv("USER")))
 		user = "you";
@@ -96,11 +95,13 @@ printfeed(FILE *fp, const char *feedname)
 		errx(1, "can't format current time");
 
 	while (parseline(&line, &linesize, fields, fp) > 0) {
-		if ((r = strtotime(fields[FieldUnixTimestamp], &parsedtime)) == -1 ||
-		    !gmtime_r(&parsedtime, &tm) ||
+		parsedtime = 0;
+		strtotime(fields[FieldUnixTimestamp], &parsedtime);
+		/* can't convert: default to formatted time for time_t 0. */
+		if (!gmtime_r(&parsedtime, &tm) ||
 		    !strftime(timebuf, sizeof(timebuf),
 		    "%a, %d %b %Y %H:%M +0000", &tm))
-			continue; /* invalid date */
+			strlcpy(timebuf, "Thu, 01 Jan 1970 00:00 +0000", sizeof(timebuf));
 
 		/* mbox + mail header */
 		printf("From MAILER-DAEMON %s\n"

sfeed_plain.c

@@ -42,8 +42,10 @@ printfeed(FILE *fp, const char *feedname)
 	time_t parsedtime;
 
 	while (parseline(&line, &size, fields, fp) > 0) {
-		if (strtotime(fields[FieldUnixTimestamp], &parsedtime) != -1 &&
-		   parsedtime >= comparetime)
+		parsedtime = 0;
+		strtotime(fields[FieldUnixTimestamp], &parsedtime);
+
+		if (parsedtime >= comparetime)
 			fputs("N ", stdout);
 		else
 			fputs("  ", stdout);

util.c

@@ -188,10 +188,11 @@ int
 strtotime(const char *s, time_t *t)
 {
 	long l;
+	char *e;
 
 	errno = 0;
-	l = strtol(s, NULL, 10);
-	if (errno != 0)
+	l = strtol(s, &e, 10);
+	if (*s == '\0' || *e != '\0')
 		return -1;
 	if (t)
 		*t = (time_t)l;