hare

commit b0499b70e5e9fdfed10b3b17cc7c00acea020473
parent 6d3ed8e222d44573dcd94ab2c19f577a4353dee8
Author: Byron Torres <b@torresjrjr.com>
Date:   Thu, 22 Feb 2024 23:43:58 +0000

time::chrono: improve LOCAL, tz()

Make [[LOCAL]] default to [[UTC]] proper.

Accept the POSIX $TZ environment variable form with a ':' prefix.

Allow [[tz]] to accept full filepaths as in POSIX.

Signed-off-by: Byron Torres <b@torresjrjr.com>

Diffstat:
M
hare/module/format.ha
 | 
2
+-
M
time/chrono/timezone.ha
 | 
78
+++++++++++++++++++++---------------------------------------------------------
M
time/chrono/tzdb.ha
 | 
20
+++++++++++++-------

3 files changed, 35 insertions(+), 65 deletions(-)
diff --git a/hare/module/format.ha b/hare/module/format.ha
@@ -35,7 +35,7 @@ export fn format_srcset(out: io::handle, srcs: *srcset) (size | io::error) = {
 	n += fmt::fprint(out, "relevant tags: ")?;
 	n += format_tags(out, srcs.seentags)?;
 	n += fmt::fprintln(out)?;
-	const dt = date::from_instant(time::chrono::LOCAL, srcs.mtime);
+	const dt = date::from_instant(chrono::LOCAL, srcs.mtime);
 	n += date::format(out, "last change to source list: %F %T\n", &dt)?;
 	n += fmt::fprintln(out, "hare sources:")?;
 	for (let i = 0z; i < len(srcs.ha); i += 1) {
diff --git a/time/chrono/timezone.ha b/time/chrono/timezone.ha
@@ -181,77 +181,41 @@ export fn fixedzone(ts: *timescale, daylen: time::duration, z: zone) timezone = 
 	};
 };
 
-// The system's [[locality]]; the system's local [[timezone]].
+// The local [[locality]]; the system or environment configured [[timezone]].
 //
 // This is set during a program's initialisation, where the TZ environment
-// variable is tried, otherwise the /etc/localtime file is tried, otherwise a
-// default is used.
-//
-// The default timezone is equivalent to that of [[UTC]], with "Local" being the
-// name of both the timezone and its single zero-offset zone.
-export const LOCAL: locality = &TZ_LOCAL;
-
-def TZ_LOCAL_NAME: str = "Local";
-
-let TZ_LOCAL: timezone = timezone {
-	name = TZ_LOCAL_NAME,
-	timescale = &utc,
-	daylength = EARTH_DAY,
-	zones = [
-		zone {
-			zoff = 0 * time::SECOND,
-			name = TZ_LOCAL_NAME,
-			abbr = "",
-			dst = false,
-		},
-	],
-	transitions = [],
-	posix_extend = "",
-};
+// variable is tried, otherwise the /etc/localtime file is tried, otherwise it
+// defaults  to [[UTC]].
+export const LOCAL: locality = &TZ_UTC;
 
 @init fn init_tz_local() void = {
-	match (os::getenv("TZ")) {
-	case let timezone: str =>
-		match (tz(timezone)) {
-		case let loc: locality =>
-			TZ_LOCAL = *loc;
-		case =>
-			return;
+	let path = match (os::getenv("TZ")) {
+	case let path: str =>
+		// remove POSIX prefix ':'
+		yield if (strings::hasprefix(path, ':')) {
+			yield strings::sub(path, 1, strings::end);
+		} else {
+			yield path;
 		};
 	case void =>
-		const filepath = match (os::readlink(LOCALTIME_PATH)) {
-		case let fp: str =>
-			yield fp;
-		case =>
-			yield LOCALTIME_PATH;
-		};
-
-		const file = match (os::open(filepath)) {
-		case let f: io::file =>
-			yield f;
+		yield match (os::realpath(LOCALTIME_PATH)) {
+		case let path: str =>
+			yield path;
 		case =>
 			return;
 		};
-		defer io::close(file)!;
-
-		if (strings::hasprefix(filepath, ZONEINFO_PREFIX)) {
-			TZ_LOCAL.name = strings::trimprefix(
-				filepath, ZONEINFO_PREFIX,
-			);
-		};
+	};
 
-		static let buf: [os::BUFSZ]u8 = [0...];
-		const file = bufio::init(file, buf, []);
-		load_tzif(&file, &TZ_LOCAL): void;
+	match (tz(path)) {
+	case => void;
+	case let loc: locality =>
+		LOCAL = loc;
 	};
 };
 
 @fini fn free_tz_local() void = {
-	free(TZ_LOCAL.transitions);
-	switch(TZ_LOCAL.name) {
-	case TZ_LOCAL_NAME => void;
-	case =>
-		free(TZ_LOCAL.zones);
+	if (LOCAL != UTC) {
+		timezone_free(LOCAL);
 	};
 };
 
diff --git a/time/chrono/tzdb.ha b/time/chrono/tzdb.ha
@@ -19,16 +19,22 @@ export type tzdberror = !(invalidtzif | fs::error | io::error);
 export type invalidtzif = !void;
 
 // Finds, loads, and allocates a [[timezone]] from the system's Timezone
-// database, normally located at /usr/share/zoneinfo, and returns it as a
-// [[locality]]. Each call returns a new instance. The caller must free the
-// return value.
+// database (TZDB), and returns it as a [[locality]]. Each call returns a new
+// instance. The caller must free the return value; see [[timezone_free]].
 //
-// All localities provided default to the [[utc]] [[timescale]] and
+// The system TZDB is normally located at [[ZONEINFO_PREFIX]]. The timezone
+// filepath is resolved by appending the name argument to this prefix path.
+// If [name] is a full filepath (begins with '/'), it is used directly instead.
+//
+// All localities returned default to the [[utc]] [[timescale]] and
 // [[EARTH_DAY]] day-length.
 export fn tz(name: str) (locality | tzdberror) = {
-	const filepath = path::init(ZONEINFO_PREFIX, name)!;
-	const fpath = path::string(&filepath);
-	const file = os::open(fpath)?;
+	const filepath =
+		if (!strings::hasprefix(name, ZONEINFO_PREFIX))
+			path::init(ZONEINFO_PREFIX, name)!
+		else
+			path::init(name)!;
+	const file = os::open(path::string(&filepath))?;
 
 	static let buf: [os::BUFSZ]u8 = [0...];
 	const bufstrm = bufio::init(file, buf, []);