diff options
Diffstat (limited to 'src/time/zoneinfo_read.go')
| -rw-r--r-- | src/time/zoneinfo_read.go | 44 |
1 files changed, 27 insertions, 17 deletions
diff --git a/src/time/zoneinfo_read.go b/src/time/zoneinfo_read.go index 22a60f3211..f7fe59c385 100644 --- a/src/time/zoneinfo_read.go +++ b/src/time/zoneinfo_read.go @@ -247,8 +247,8 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) { // This also avoids a panic later when we add and then use a fake transition (golang.org/issue/29437). return nil, badData } - zone := make([]zone, nzone) - for i := range zone { + zones := make([]zone, nzone) + for i := range zones { var ok bool var n uint32 if n, ok = zonedata.big4(); !ok { @@ -257,22 +257,22 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) { if uint32(int(n)) != n { return nil, badData } - zone[i].offset = int(int32(n)) + zones[i].offset = int(int32(n)) var b byte if b, ok = zonedata.byte(); !ok { return nil, badData } - zone[i].isDST = b != 0 + zones[i].isDST = b != 0 if b, ok = zonedata.byte(); !ok || int(b) >= len(abbrev) { return nil, badData } - zone[i].name = byteString(abbrev[b:]) + zones[i].name = byteString(abbrev[b:]) if runtime.GOOS == "aix" && len(name) > 8 && (name[:8] == "Etc/GMT+" || name[:8] == "Etc/GMT-") { // There is a bug with AIX 7.2 TL 0 with files in Etc, // GMT+1 will return GMT-1 instead of GMT+1 or -01. if name != "Etc/GMT+0" { // GMT+0 is OK - zone[i].name = name[4:] + zones[i].name = name[4:] } } } @@ -295,7 +295,7 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) { } } tx[i].when = n - if int(txzones[i]) >= len(zone) { + if int(txzones[i]) >= len(zones) { return nil, badData } tx[i].index = txzones[i] @@ -314,7 +314,7 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) { } // Committed to succeed. - l := &Location{zone: zone, tx: tx, name: name, extend: extend} + l := &Location{zone: zones, tx: tx, name: name, extend: extend} // Fill in the cache with information about right now, // since that will be the most common lookup. @@ -323,26 +323,27 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) { if tx[i].when <= sec && (i+1 == len(tx) || sec < tx[i+1].when) { l.cacheStart = tx[i].when l.cacheEnd = omega - zoneIdx := tx[i].index + l.cacheZone = &l.zone[tx[i].index] if i+1 < len(tx) { l.cacheEnd = tx[i+1].when } else if l.extend != "" { // If we're at the end of the known zone transitions, // try the extend string. - if name, _, estart, eend, ok := tzset(l.extend, l.cacheEnd, sec); ok { + if name, offset, estart, eend, isDST, ok := tzset(l.extend, l.cacheEnd, sec); ok { l.cacheStart = estart l.cacheEnd = eend - // Find the zone that is returned by tzset, - // the last transition is not always the correct zone. - for i, z := range l.zone { - if z.name == name { - zoneIdx = uint8(i) - break + // Find the zone that is returned by tzset to avoid allocation if possible. + if zoneIdx := findZone(l.zone, name, offset, isDST); zoneIdx != -1 { + l.cacheZone = &l.zone[zoneIdx] + } else { + l.cacheZone = &zone{ + name: name, + offset: offset, + isDST: isDST, } } } } - l.cacheZone = &l.zone[zoneIdx] break } } @@ -350,6 +351,15 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) { return l, nil } +func findZone(zones []zone, name string, offset int, isDST bool) int { + for i, z := range zones { + if z.name == name && z.offset == offset && z.isDST == isDST { + return i + } + } + return -1 +} + // loadTzinfoFromDirOrZip returns the contents of the file with the given name // in dir. dir can either be an uncompressed zip file, or a directory. func loadTzinfoFromDirOrZip(dir, name string) ([]byte, error) { |