Import parse_timestamp() from ostree

Closes: #1538
Approved by: alexlarsson

app/Makefile.am.inc

@@ -2,6 +2,8 @@ bin_PROGRAMS += \
 	flatpak \
 	$(NULL)
 
+EXTRA_DIST += app/parse-datetime.y
+
 flatpak_SOURCES = \
 	app/flatpak-main.c \
 	app/flatpak-builtins.h \
@@ -39,6 +41,8 @@ flatpak_SOURCES = \
 	app/flatpak-builtins-document-info.c \
 	app/flatpak-builtins-document-list.c \
 	app/flatpak-builtins-search.c \
+	app/parse-datetime.c \
+	app/parse-datetime.h \
 	$(NULL)
 
 flatpak_LDADD = $(AM_LDADD) $(BASE_LIBS) $(OSTREE_LIBS) $(SOUP_LIBS) $(JSON_LIBS) $(APPSTREAM_GLIB_LIBS) \

app/parse-datetime.h

@@ -0,0 +1,22 @@
+/* Parse a string into an internal time stamp.
+
+   Copyright (C) 1995, 1997-1998, 2003-2004, 2007, 2009-2015 Free Software
+   Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify it
+   under the terms of the GNU Lesser General Public License as published
+   by the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <stdbool.h>
+#include <time.h>
+
+bool parse_datetime (struct timespec *, char const *, struct timespec const *);