Add documentation for X509 time functions

[ci skip]

Reviewed-by: Tim Hudson <[email protected]>

doc/man3/X509_cmp_time.pod

@@ -6,26 +6,47 @@ X509_cmp_time - X509 time functions
 
 =head1 SYNOPSIS
 
- X509_cmp_time(const ASN1_TIME *asn1_time, time_t *cmp_time);
+ int X509_cmp_time(const ASN1_TIME *asn1_time, time_t *in_tm);
+ int X509_cmp_current_time(const ASN1_TIME *asn1_time);
+ ASN1_TIME *X509_time_adj(ASN1_TIME *asn1_time, long offset_sec, time_t *in_tm);
+ ASN1_TIME *X509_time_adj_ex(ASN1_TIME *asn1_time, int offset_day, long
+                             offset_sec, time_t *in_tm);
 
 =head1 DESCRIPTION
 
-X509_cmp_time() compares the ASN1_TIME in B<asn1_time> with the time in
-<cmp_time>.
+X509_cmp_time() compares the ASN1_TIME in B<asn1_time> with the time
+in <cmp_time>. X509_cmp_current_time() compares the ASN1_TIME in
+B<asn1_time> with the current time, expressed as time_t. B<asn1_time>
+must satisfy the ASN1_TIME format mandated by RFC 5280, i.e., its
+format must be either YYMMDDHHMMSSZ or YYYYMMDDHHMMSSZ.
 
-B<asn1_time> must satisfy the ASN1_TIME format mandated by RFC 5280, i.e.,
-its format must be either YYMMDDHHMMSSZ or YYYYMMDDHHMMSSZ.
+X509_time_adj_ex() sets the ASN1_TIME structure B<asn1_time> to the time
+B<offset_day> and B<offset_sec> after B<in_tm>.
 
-If B<cmp_time> is NULL the current time is used.
+X509_time_adj() sets the ASN1_TIME structure B<asn1_time> to the time
+B<offset_sec> after B<in_tm>. This method can only handle second
+offsets up to the capacity of long, so the newer X509_time_adj_ex()
+API should be preferred.
+
+In both methods, if B<asn1_time> is NULL, a new ASN1_TIME structure
+is allocated and returned.
+
+In all methods, if B<in_tm> is NULL, the current time, expressed as
+time_t, is used.
 
 =head1 BUGS
 
-Unlike many standard comparison functions, X509_cmp_time returns 0 on error.
+Unlike many standard comparison functions, X509_cmp_time() and
+X509_cmp_current_time() return 0 on error.
 
 =head1 RETURN VALUES
 
-X509_cmp_time() returns -1 if B<asn1_time> is earlier than, or equal to,
-B<cmp_time>, and 1 otherwise. It returns 0 on error.
+X509_cmp_time() and X509_cmp_current_time() return -1 if B<asn1_time>
+is earlier than, or equal to, B<cmp_time> (resp. current time), and 1
+otherwise. These methods return 0 on error.
+
+X509_time_ad() and X509_time_adj_ex() return a pointer to the updated
+ASN1_TIME structure, and NULL on error.
 
 =head1 COPYRIGHT