Retro68/gcc/libgo/go/time/zoneinfo_unix.go
2017-04-10 13:32:00 +02:00

87 lines
2.0 KiB
Go

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build darwin,386 darwin,amd64 dragonfly freebsd linux nacl netbsd openbsd solaris
// Parse "zoneinfo" time zone file.
// This is a fairly standard file format used on OS X, Linux, BSD, Sun, and others.
// See tzfile(5), http://en.wikipedia.org/wiki/Zoneinfo,
// and ftp://munnari.oz.au/pub/oldtz/
package time
import (
"errors"
"runtime"
"syscall"
)
func initTestingZone() {
syscall.Setenv("TZ", "America/Los_Angeles")
initLocal()
}
// Many systems use /usr/share/zoneinfo, Solaris 2 has
// /usr/share/lib/zoneinfo, IRIX 6 has /usr/lib/locale/TZ.
var zoneDirs = []string{
"/usr/share/zoneinfo/",
"/usr/share/lib/zoneinfo/",
"/usr/lib/locale/TZ/",
runtime.GOROOT() + "/lib/time/zoneinfo.zip",
}
var origZoneDirs = zoneDirs
func forceZipFileForTesting(zipOnly bool) {
zoneDirs = make([]string, len(origZoneDirs))
copy(zoneDirs, origZoneDirs)
if zipOnly {
for i := 0; i < len(zoneDirs)-1; i++ {
zoneDirs[i] = "/XXXNOEXIST"
}
}
}
func initLocal() {
// consult $TZ to find the time zone to use.
// no $TZ means use the system default /etc/localtime.
// $TZ="" means use UTC.
// $TZ="foo" means use /usr/share/zoneinfo/foo.
tz, ok := syscall.Getenv("TZ")
switch {
case !ok:
z, err := loadZoneFile("", "/etc/localtime")
if err == nil {
localLoc = *z
localLoc.name = "Local"
return
}
case tz != "" && tz != "UTC":
if z, err := loadLocation(tz); err == nil {
localLoc = *z
return
}
}
// Fall back to UTC.
localLoc.name = "UTC"
}
func loadLocation(name string) (*Location, error) {
var firstErr error
for _, zoneDir := range zoneDirs {
if z, err := loadZoneFile(zoneDir, name); err == nil {
z.name = name
return z, nil
} else if firstErr == nil && !isNotExist(err) {
firstErr = err
}
}
if firstErr != nil {
return nil, firstErr
}
return nil, errors.New("unknown time zone " + name)
}