From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from m0.truegem.net (m0.truegem.net [69.55.228.47]) by sourceware.org (Postfix) with ESMTPS id 0E343388A835 for ; Wed, 13 May 2020 08:24:25 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 0E343388A835 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=maxrnd.com Authentication-Results: sourceware.org; spf=none smtp.mailfrom=mark@maxrnd.com Received: (from daemon@localhost) by m0.truegem.net (8.12.11/8.12.11) id 04D8OKf9090265; Wed, 13 May 2020 01:24:20 -0700 (PDT) (envelope-from mark@maxrnd.com) Received: from 162-235-43-67.lightspeed.irvnca.sbcglobal.net(162.235.43.67), claiming to be "localhost.localdomain" via SMTP by m0.truegem.net, id smtpdFXH8xz; Wed May 13 01:24:14 2020 From: Mark Geisert To: cygwin-patches@cygwin.com Subject: [Cygwin PATCH 2/9] tzcode resync: README Date: Wed, 13 May 2020 01:23:42 -0700 Message-Id: <20200513082349.831-2-mark@maxrnd.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20200513082349.831-1-mark@maxrnd.com> References: <20200513082349.831-1-mark@maxrnd.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-14.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, KAM_LAZY_DOMAIN_SECURITY, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: cygwin-patches@cygwin.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Cygwin core component patch submission and discussion List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 May 2020 08:24:27 -0000 --- winsup/cygwin/tzcode/README | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 winsup/cygwin/tzcode/README diff --git a/winsup/cygwin/tzcode/README b/winsup/cygwin/tzcode/README new file mode 100644 index 000000000..a200502ea --- /dev/null +++ b/winsup/cygwin/tzcode/README @@ -0,0 +1,37 @@ +/* + How the code in this directory is supposed to work... + 2020/05/13 Mark Geisert + + localtime.cc is the Cygwin-specific module that is compiled into + the Cygwin DLL when the latter is built. It's just a wrapper that + #defines a bunch of stuff then #includes localtime.c. + + localtime.c, at any point in time, is a reasonably recent version + of /src/lib/libc/time/localtime.c from NetBSD. The same goes for + private.h and tzfile.h. OTOH namespace.h implements something on + NetBSD that is not provided on Cygwin, so it's empty here. + + The idea is that in the future, one just needs to bring over newer + versions of localtime.c, private.h, and/or tzfile.h from NetBSD as + they become available. + + With luck, you can drop those files into this directory and they + can be immediately used to build a newer Cygwin DLL that has the + newer NetBSD functionality. Without luck, you'll have to tweak the + wrapper localtime.cc. In the worst case, some other strategy will + need to be figured out, such as manually pulling out the parts of + the NetBSD code Cygwin needs to build a stand-alone localtime.cc. + + Re tz_posixrules.h: The data elements can be generated from + /usr/share/zoneinfo/posixrules in any version of Cygwin's tzdata + package. Instructions are in the comment heading tz_posixrules.h. + + Addendum: + Implementation of the strategy above has uncovered a small number + of NetBSD-isms in localtime.c that cannot be worked around with + preprocessor tricks. So there is another file localtime.c.patched + that holds just these adjustments for Cygwin, and it's this file + that localtime.cc #includes. + + ..mark +*/ -- 2.21.0