7 files changed, 14 insertions, 3 deletions
diff --git a/src/libnetdata/datetime/README.md b/src/libnetdata/datetime/README.md
new file mode 100644
index 000000000..303ba8bf2
--- /dev/null
+++ b/src/libnetdata/datetime/README.md
@@ -0,0 +1,11 @@
+<!--
+title: "Datetime"
+custom_edit_url: https://github.com/netdata/netdata/edit/master/src/libnetdata/datetime/README.md
+sidebar_label: "Datetime"
+learn_topic_type: "Tasks"
+learn_rel_path: "Developers/libnetdata"
+-->
+
+# Datetime
+
+Formatting dates and timestamps.
diff --git a/libnetdata/datetime/iso8601.c b/src/libnetdata/datetime/iso8601.c
index 8e3f4e027..8e3f4e027 100644
--- a/libnetdata/datetime/iso8601.c
+++ b/src/libnetdata/datetime/iso8601.c
diff --git a/libnetdata/datetime/iso8601.h b/src/libnetdata/datetime/iso8601.h
index ce4800963..ce4800963 100644
--- a/libnetdata/datetime/iso8601.h
+++ b/src/libnetdata/datetime/iso8601.h
diff --git a/libnetdata/datetime/rfc3339.c b/src/libnetdata/datetime/rfc3339.c
index 157e340d3..5c4e990dd 100644
--- a/libnetdata/datetime/rfc3339.c
+++ b/src/libnetdata/datetime/rfc3339.c
@@ -27,7 +27,7 @@ size_t rfc3339_datetime_ut(char *buffer, size_t len, usec_t now_ut, size_t fract
         return 0;
     }
 
-    if (fractional_digits >= 0 && fractional_digits <= 9) {
+    if (fractional_digits >= 1 && fractional_digits <= 9) {
         int fractional_part = (int)(now_ut % USEC_PER_SEC);
         if (fractional_part && len - used_length > fractional_digits + 1) {
             char format[] = ".%01d";
@@ -102,8 +102,8 @@ usec_t rfc3339_parse_ut(const char *rfc3339, char **endptr) {
     if (*s == '+' || *s == '-') {
         // Parse the hours:mins part of the timezone
 
-        if (!isdigit(s[1]) || !isdigit(s[2]) || s[3] != ':' ||
-            !isdigit(s[4]) || !isdigit(s[5]))
+        if (!isdigit((uint8_t)s[1]) || !isdigit((uint8_t)s[2]) || s[3] != ':' ||
+            !isdigit((uint8_t)s[4]) || !isdigit((uint8_t)s[5]))
             return 0; // Parsing error
 
         char tz_sign = *s;
diff --git a/libnetdata/datetime/rfc3339.h b/src/libnetdata/datetime/rfc3339.h
index 88ebb3ec8..88ebb3ec8 100644
--- a/libnetdata/datetime/rfc3339.h
+++ b/src/libnetdata/datetime/rfc3339.h
diff --git a/libnetdata/datetime/rfc7231.c b/src/libnetdata/datetime/rfc7231.c
index 4925ed2c9..4925ed2c9 100644
--- a/libnetdata/datetime/rfc7231.c
+++ b/src/libnetdata/datetime/rfc7231.c
diff --git a/libnetdata/datetime/rfc7231.h b/src/libnetdata/datetime/rfc7231.h
index 5ba93053f..5ba93053f 100644
--- a/libnetdata/datetime/rfc7231.h
+++ b/src/libnetdata/datetime/rfc7231.h