RSS (pubDate) uses RFC822 dates. This standard is obsoleted by RFC2822.
The RSS 2.0 spec says for the pubDate field:
"[...] All date-times in RSS conform to the Date and Time Specification of RFC
822, with the exception that the year may be expressed with two characters or
four characters (four preferred)."
RFC822 section 5.1 describes the syntax with 2 digit years:
https://datatracker.ietf.org/doc/html/rfc822#section-5.1
It was obsoleted/fixed in RFC2822 section 4.3:
https://datatracker.ietf.org/doc/html/rfc2822#section-4.3
" Where a two or three digit year occurs in a date, the year is to be
interpreted as follows: If a two digit year is encountered whose
value is between 00 and 49, the year is interpreted by adding 2000,
ending up with a value between 2000 and 2049. If a two digit year is
encountered with a value between 50 and 99, or any three digit year
is encountered, the year is interpreted by adding 1900."
In the real world I've seen all sites using RSS use the 4-digit format.
For historic context of changes and what feeds it might affect:
- RFC822 was published in 13 august 1982, obsoleted by RFC2822.
- RFC2822 was published in april 2001, obsoleted by RFC5322.
- RFC5322 was published in october 2008.
- RDF was started around 1996. It was published around 2004.
- March 15, 1999: RSS 0.90 (Netscape), published by Netscape and authored by
Ramanathan Guha.
- July 10, 1999: RSS 0.91 (Netscape), published by Netscape and authored by Dan
Libby.
- June 9, 2000: RSS 0.91 (UserLand), published by UserLand Software and
authored by Dave Winer.
- Dec. 25, 2000: RSS 0.92, UserLand.
- Aug. 19, 2002: RSS 2.0, UserLand.
- July 15, 2003: RSS 2.0 (version 2.0.1), published by the Berkman Center for
Internet & Society at Harvard Law School and authored by Dave Winer.
- July 15, 2003: RSS 2.0 (version 2.0.1-rv-1), published by the RSS Advisory
Board.
- July 17, 2003: RSS 2.0 (version 2.0.1-rv-2), RSS Advisory Board.
- April 6, 2004: RSS 2.0 (version 2.0.1-rv-3), RSS Advisory Board.
- May 31, 2004: RSS 2.0 (version 2.0.1-rv-4), RSS Advisory Board.
- June 19, 2004: RSS 2.0 (version 2.0.1-rv-5), RSS Advisory Board.
- January 25, 2005: RSS 2.0 (version 2.0.1-rv-6), RSS Advisory Board.
- Aug. 12, 2006: RSS 2.0 (version 2.0.8), RSS Advisory Board.
- June 5, 2007: RSS 2.0 (version 2.0.9), RSS Advisory Board.
- Oct. 15, 2007: RSS 2.0 (version 2.0.10), RSS Advisory Board.
- March 30, 2009 (current): RSS 2.0 (version 2.0.11), RSS Advisory Board.
RSS history source: https://www.rssboard.org/rss-history
- Add SFEED_MBOX_CONTENT environment option. When set to "1" it outputs the
content aswell. This is disabled by default for security reasons, because many
clients handle HTML in an insecure way.
- Print link and enclosure on one line and align them.
This fixes a warning on Linux glibc:
/usr/include/features.h:187:3: warning: #warning "_BSD_SOURCE and _SVID_SOURCE are deprecated, use _DEFAULT_SOURCE" [-Wcpp]
187 | # warning "_BSD_SOURCE and _SVID_SOURCE are deprecated, use _DEFAULT_SOURCE"
| ^~~~~~~
Tested on Void GNU/Linux glibc with gcc. Tested on various other platforms for
regressions too namely: OpenBSD, NetBSD, FreeBSD, Void GNU/Linux musl.
These are BSD functions.
- HaikuOS now compiles without having to use libbsd.
- Tested on SerenityOS (for fun), which doesn't have these functions (yet).
With a small change to support wcwidth() sfeed works on SerenityOS.
- Do not show stderr of readlink.
- Show the reference to the example sfeedrc (like sfeed_update).
- Make the error message a bit shorter.
- Fix showing the path if it does not exist, for example:
$ sfeed_opml_export "a"
readlink: a: No such file or directory
Configuration file "" does not exist or is not readable.
Now shows:
$ sfeed_opml_export "a"
Configuration file "a" cannot be read.
See sfeedrc.example for an example.
This title format now matches the one with sfeed_curses. It shows the count to
the most left and makes it more readable imho. It also works better when the
titlebar is small.
When sfeed_update was called without using a parameter and it used the default
and this path did not exist it would incorrectly print:
Configuration file "" does not exist or is not readable.
See sfeedrc.example for an example.
Make the error message a bit shorter too.
This was a partial regression of commit df74ba274c
getchar_unlocked is part of POSIX and should be supported by most platforms. On
all tested platforms it has a performance benefit, sometimes smallish (<12%),
sometimes large (~40%).
Since newsboat version 2.22 (2020-12-21) it stores the content mime-type of a
field so allow to export this.
The older entries are empty and will be exported as "html" (even though they
might have been plain-text).
... also add the (empty) category field.
Workaround it by setting the empty "middle" fields to some value. The last
field can be empty.
Some feeds were incorrectly using the wrong base URL if the `baseurl` field was
empty but the encoding field was set. So it incorrectly used the encoding field
instead.
Only now noticed some feeds were failing because the baseURL is validated since
commit f305b032bc and returning a non-zero exit
status.
This doesn't happen with GNU xargs, busybox or toybox xargs.
Affected (atleast): OpenBSD, NetBSD, FreeBSD and DragonFlyBSD xargs which share
similar code.
Simple way to reproduce the difference:
printf 'a\0\0c\0' | xargs -0 echo
Prints "a c" on *BSD.
Prints "a c" on GNU xargs (and some other implementations).
Follow-up from a rushed commit:
commit 58555779d1
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date: Sun Feb 28 13:33:21 2021 +0100
sfeed_update: simplify, use feedurl directly
This also make it possible to use non-authoritive URLs as a baseurl, like
"magnet:" URLs.
Removed/rewritten the functions:
absuri, parseuri, and encodeuri() for percent-encoding.
The functions are now split separately with the following purpose:
- uri_format: format struct uri into a string.
- uri_hasscheme: quick check if a string is absolute or not.
- uri_makeabs: make a URI absolute using a base uri and the original URI.
- uri_parse: parse a string into a struct uri.
The following URLs are better parsed:
- URLs with extra "/"'s in the path prepended are kept as is, no "/" is added
either for empty paths.
- URLs like "http://codemadness.org" are not changed to
"http://codemadness.org/" anymore (paths are kept as is, unless they are
non-empty and not start with "/").
- Paths are not percent-encoded anymore.
- URLs with userinfo field (username, password) are parsed.
like: ftp://user:password@[2001:db8::7]:2121/rfc/rfc1808.txt
- Non-authoritive URLs like mailto:some@email.org, magnet URIs, ISBN URIs/urn,
like: urn:isbn:0-395-36341-1 are allowed and parsed correctly.
- Both local (file:///) and non-local (file://) are supported.
- Specifying a base URL with a port will now only use it when the relative URL
has no host and port set and follows RFC3986 5.2.2 more closely.
- Parsing numeric port: parse as signed long and check <= 0, empty port is
allowed.
- Parsing URIs containing query, fragment, but no path separator (/) will now
parse the component properly.
For sfeed:
- Parse the baseURI only once (no need to do it every time for making absolute
URIs).
- If a link/enclosure is absolute already or if there is no base URL specified
then just print the link directly. There have also been other small performance
improvements related to handling URIs.
References:
- https://tools.ietf.org/html/rfc3986
- Section "5.2.2. Transform References" have also been helpful.
Combine E-Tags, If-Modified-Since in one section. Also mention the curl
--compression option for typically GZIP decompression.
Note that E-Tags were broken in curl <7.73 due to a bug with "weak" e-tags.
https://github.com/curl/curl/issues/5610
From a question/feedback by e-mail from Hadrien Lacour, thanks.
Hiltjo Posthuma