Re: Problem with Google Calendar Synchronization

[Guido Van Hoecke <guivho@gmail.com>]

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Eric,

Eric S Fraga <e.fraga@ucl.ac.uk> writes:

> Guido Van Hoecke <guivho@gmail.com> writes:
>
> [...]
>
>> My ics file had a.o. my elder sister's birthday, and unfortunately her's
>> as well as mine is (way) before the start of the epoch, so mktime
>> returns a negative timestamp at line 63 and strftime at line 143 doesn't
>> grok it.
>
> Ah, I see.  The script should at least not break just because some of us
> (me included) are older than Unix... ;-)
>
> The fix should be straightforward.  Could you try adding the lines
>
>    if (timestamp < 0) timestamp = 0;
>
> after the call to mktime in the datetimestamp function?  This should at
> least make the script not crap out although obviously the date will be
> wrong (set to start of epoch).  If this works, I will update the script
> on Worg and put in a warning message of some sort, maybe even in the
> entry itself.

With this change the script assigns the wrong date, but no longer stops.

> Suggestions on how to handle this case would be welcome, of course.

I created a patch so that the date and time string is built directly
from the iCal data for times before the epoch. This function produces
valid date/time strings albeit without weekday info.

Patch file is attached.


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--- ical2org.awk.orig	2013-05-09 14:15:14.000000000 +0200
+++ ical2org.awk	2013-05-09 15:11:44.000000000 +0200
@@ -27,7 +27,7 @@
 # no further revision log after this as the file was moved into a git
 # repository...
 #
-# Last change: 2011.01.28 16:08:03
+# Last change: 2013.05.09 15:11:44
 #----------------------------------------------------------------------------------

 # a function to take the iCal formatted date+time, convert it into an
@@ -60,12 +60,31 @@

     # print "adjusted    : " timestamp
     # print "Time stamp  : " strftime("%Y-%m-%d %H:%M", timestamp);
+    if(timestamp < 0) timestamp = 0;
     return timestamp;
 }

+# a function to comvert the iCal date+time string into a date time string;
+# it uses the datetimestamp subroutine to compute the value to feed to strftime;
+# if the iCal date falls before time 0, the string is built from the iCal input;
+
+function datetimestring(input)
+{
+    # try to create datetimestring from the datetimestamp
+    timestamp = datetimestamp(input);
+    if (timestamp > 0)
+        return strftime("%Y-%m-%d %a %H:%M", datetimestamp(datetmp));
+
+    # this is a date before the start of the epoch
+    # create the yyyy-mm-dd hh:mm string from the input (without day of week)
+    datespec = gensub("([0-9][0-9][0-9][0-9])([0-9][0-9])([0-9][0-9])T([0-9][0-9])([0-9][0-9])([0-9][0-9]).*[\r]*", "\\1-\\2-\\3 \\4:\\5", "g", input);
+    # print "==> datespec:" datespec;
+    return datespec;
+}
+
 BEGIN {
     ### config section
-    max_age =  7; # in days
+    max_age =  -1; #7; # in days
                   # set this to -1 to get all entries or to N>0 to only get
                   # that start or end less than N days ago
     ### end config section
@@ -90,6 +109,7 @@
     indescription = 0;
     lasttimestamp=-1;

+
     print "#+TITLE:     Main Google calendar entries"
     print "#+AUTHOR:    Eric S Fraga"
     print "#+EMAIL:     e.fraga@ucl.ac.uk"
@@ -140,12 +160,12 @@

 /^DTSTART;VALUE=DATE/ {
     datetmp = gensub("([0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9])(.*[\r])", "\\1T000000\\2", "g", $2)
-    date = strftime("%Y-%m-%d %a %H:%M", datetimestamp(datetmp));
+    date = datetimestring(datetmp);
     if(max_age>0)     lasttimestamp = datetimestamp(datetmp);
 }
 /^DTEND;VALUE=DATE/ {
     datetmp = gensub("([0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9])(.*[\r])", "\\1T000000\\2", "g", $2)
-    time2 = strftime("%Y-%m-%d %a %H:%M", datetimestamp(datetmp));
+    time2 = datetimestring(datetmp);
     date = date ">--<" time2;
     if(max_age>0)     lasttimestamp = datetimestamp(datetmp);
 }
@@ -154,7 +174,7 @@
 # we ignore the seconds

 /^DTSTART[:;][^V]/ {
-    date = strftime("%Y-%m-%d %a %H:%M", datetimestamp($2));
+    date = datetimestring($2);
     if(max_age>0)     lasttimestamp = datetimestamp($2);
     # print date;
 }
@@ -165,7 +185,7 @@

 /^DTEND[:;][^V]/ {
     # print $0
-    time2 = strftime("%Y-%m-%d %a %H:%M", datetimestamp($2));
+    time2 = datetimestring($2);
     date = date ">--<" time2;
     if(max_age>0)     lasttimestamp = datetimestamp($2);
 }

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Kind regards,


Guido

--
Accident:
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	but absence of body is better.
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