diff options
Diffstat (limited to 'src/kube2msb/vendor/github.com/ugorji/go/codec/helper_internal.go')
-rw-r--r-- | src/kube2msb/vendor/github.com/ugorji/go/codec/helper_internal.go | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/src/kube2msb/vendor/github.com/ugorji/go/codec/helper_internal.go b/src/kube2msb/vendor/github.com/ugorji/go/codec/helper_internal.go new file mode 100644 index 0000000..dea981f --- /dev/null +++ b/src/kube2msb/vendor/github.com/ugorji/go/codec/helper_internal.go @@ -0,0 +1,242 @@ +// Copyright (c) 2012-2015 Ugorji Nwoke. All rights reserved. +// Use of this source code is governed by a MIT license found in the LICENSE file. + +package codec + +// All non-std package dependencies live in this file, +// so porting to different environment is easy (just update functions). + +import ( + "errors" + "fmt" + "math" + "reflect" +) + +func panicValToErr(panicVal interface{}, err *error) { + if panicVal == nil { + return + } + // case nil + switch xerr := panicVal.(type) { + case error: + *err = xerr + case string: + *err = errors.New(xerr) + default: + *err = fmt.Errorf("%v", panicVal) + } + return +} + +func hIsEmptyValue(v reflect.Value, deref, checkStruct bool) bool { + switch v.Kind() { + case reflect.Invalid: + return true + case reflect.Array, reflect.Map, reflect.Slice, reflect.String: + return v.Len() == 0 + case reflect.Bool: + return !v.Bool() + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + return v.Int() == 0 + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: + return v.Uint() == 0 + case reflect.Float32, reflect.Float64: + return v.Float() == 0 + case reflect.Interface, reflect.Ptr: + if deref { + if v.IsNil() { + return true + } + return hIsEmptyValue(v.Elem(), deref, checkStruct) + } else { + return v.IsNil() + } + case reflect.Struct: + if !checkStruct { + return false + } + // return true if all fields are empty. else return false. + // we cannot use equality check, because some fields may be maps/slices/etc + // and consequently the structs are not comparable. + // return v.Interface() == reflect.Zero(v.Type()).Interface() + for i, n := 0, v.NumField(); i < n; i++ { + if !hIsEmptyValue(v.Field(i), deref, checkStruct) { + return false + } + } + return true + } + return false +} + +func isEmptyValue(v reflect.Value) bool { + return hIsEmptyValue(v, derefForIsEmptyValue, checkStructForEmptyValue) +} + +func pruneSignExt(v []byte, pos bool) (n int) { + if len(v) < 2 { + } else if pos && v[0] == 0 { + for ; v[n] == 0 && n+1 < len(v) && (v[n+1]&(1<<7) == 0); n++ { + } + } else if !pos && v[0] == 0xff { + for ; v[n] == 0xff && n+1 < len(v) && (v[n+1]&(1<<7) != 0); n++ { + } + } + return +} + +func implementsIntf(typ, iTyp reflect.Type) (success bool, indir int8) { + if typ == nil { + return + } + rt := typ + // The type might be a pointer and we need to keep + // dereferencing to the base type until we find an implementation. + for { + if rt.Implements(iTyp) { + return true, indir + } + if p := rt; p.Kind() == reflect.Ptr { + indir++ + if indir >= math.MaxInt8 { // insane number of indirections + return false, 0 + } + rt = p.Elem() + continue + } + break + } + // No luck yet, but if this is a base type (non-pointer), the pointer might satisfy. + if typ.Kind() != reflect.Ptr { + // Not a pointer, but does the pointer work? + if reflect.PtrTo(typ).Implements(iTyp) { + return true, -1 + } + } + return false, 0 +} + +// validate that this function is correct ... +// culled from OGRE (Object-Oriented Graphics Rendering Engine) +// function: halfToFloatI (http://stderr.org/doc/ogre-doc/api/OgreBitwise_8h-source.html) +func halfFloatToFloatBits(yy uint16) (d uint32) { + y := uint32(yy) + s := (y >> 15) & 0x01 + e := (y >> 10) & 0x1f + m := y & 0x03ff + + if e == 0 { + if m == 0 { // plu or minus 0 + return s << 31 + } else { // Denormalized number -- renormalize it + for (m & 0x00000400) == 0 { + m <<= 1 + e -= 1 + } + e += 1 + const zz uint32 = 0x0400 + m &= ^zz + } + } else if e == 31 { + if m == 0 { // Inf + return (s << 31) | 0x7f800000 + } else { // NaN + return (s << 31) | 0x7f800000 | (m << 13) + } + } + e = e + (127 - 15) + m = m << 13 + return (s << 31) | (e << 23) | m +} + +// GrowCap will return a new capacity for a slice, given the following: +// - oldCap: current capacity +// - unit: in-memory size of an element +// - num: number of elements to add +func growCap(oldCap, unit, num int) (newCap int) { + // appendslice logic (if cap < 1024, *2, else *1.25): + // leads to many copy calls, especially when copying bytes. + // bytes.Buffer model (2*cap + n): much better for bytes. + // smarter way is to take the byte-size of the appended element(type) into account + + // maintain 3 thresholds: + // t1: if cap <= t1, newcap = 2x + // t2: if cap <= t2, newcap = 1.75x + // t3: if cap <= t3, newcap = 1.5x + // else newcap = 1.25x + // + // t1, t2, t3 >= 1024 always. + // i.e. if unit size >= 16, then always do 2x or 1.25x (ie t1, t2, t3 are all same) + // + // With this, appending for bytes increase by: + // 100% up to 4K + // 75% up to 8K + // 50% up to 16K + // 25% beyond that + + // unit can be 0 e.g. for struct{}{}; handle that appropriately + var t1, t2, t3 int // thresholds + if unit <= 1 { + t1, t2, t3 = 4*1024, 8*1024, 16*1024 + } else if unit < 16 { + t3 = 16 / unit * 1024 + t1 = t3 * 1 / 4 + t2 = t3 * 2 / 4 + } else { + t1, t2, t3 = 1024, 1024, 1024 + } + + var x int // temporary variable + + // x is multiplier here: one of 5, 6, 7 or 8; incr of 25%, 50%, 75% or 100% respectively + if oldCap <= t1 { // [0,t1] + x = 8 + } else if oldCap > t3 { // (t3,infinity] + x = 5 + } else if oldCap <= t2 { // (t1,t2] + x = 7 + } else { // (t2,t3] + x = 6 + } + newCap = x * oldCap / 4 + + if num > 0 { + newCap += num + } + + // ensure newCap is a multiple of 64 (if it is > 64) or 16. + if newCap > 64 { + if x = newCap % 64; x != 0 { + x = newCap / 64 + newCap = 64 * (x + 1) + } + } else { + if x = newCap % 16; x != 0 { + x = newCap / 16 + newCap = 16 * (x + 1) + } + } + return +} + +func expandSliceValue(s reflect.Value, num int) reflect.Value { + if num <= 0 { + return s + } + l0 := s.Len() + l1 := l0 + num // new slice length + if l1 < l0 { + panic("ExpandSlice: slice overflow") + } + c0 := s.Cap() + if l1 <= c0 { + return s.Slice(0, l1) + } + st := s.Type() + c1 := growCap(c0, int(st.Elem().Size()), num) + s2 := reflect.MakeSlice(st, l1, c1) + // println("expandslicevalue: cap-old: ", c0, ", cap-new: ", c1, ", len-new: ", l1) + reflect.Copy(s2, s) + return s2 +} |