mirror of
https://github.com/superseriousbusiness/gotosocial.git
synced 2024-11-25 21:26:40 +00:00
405 lines
7.6 KiB
Go
405 lines
7.6 KiB
Go
package structr
|
|
|
|
import (
|
|
"reflect"
|
|
"sync"
|
|
"unsafe"
|
|
|
|
"github.com/zeebo/xxh3"
|
|
)
|
|
|
|
var hash_pool sync.Pool
|
|
|
|
func get_hasher() *xxh3.Hasher {
|
|
v := hash_pool.Get()
|
|
if v == nil {
|
|
v = new(xxh3.Hasher)
|
|
}
|
|
return v.(*xxh3.Hasher)
|
|
}
|
|
|
|
func hash_sum(fields []structfield, h *xxh3.Hasher, key []any) (Hash, bool) {
|
|
if len(key) != len(fields) {
|
|
panicf("incorrect number key parts: want=%d received=%d",
|
|
len(key),
|
|
len(fields),
|
|
)
|
|
}
|
|
var zero bool
|
|
h.Reset()
|
|
for i, part := range key {
|
|
zero = fields[i].hasher(h, part) || zero
|
|
}
|
|
// See: https://github.com/Cyan4973/xxHash/issues/453#issuecomment-696838445
|
|
//
|
|
// In order to extract 32-bit from a good 64-bit hash result,
|
|
// there are many possible choices, which are all valid.
|
|
// I would typically grab the lower 32-bit and call it a day.
|
|
//
|
|
// Grabbing any other 32-bit (the upper part for example) is fine too.
|
|
//
|
|
// xoring higher and lower bits makes more sense whenever the produced hash offers dubious quality.
|
|
// FNV, for example, has poor mixing in its lower bits, so it's better to mix with the higher bits.
|
|
//
|
|
// XXH3 already performs significant output mixing before returning the data,
|
|
// so it's not beneficial to add another xorfold stage.
|
|
return uint64ToHash(h.Sum64()), zero
|
|
}
|
|
|
|
func hasher(t reflect.Type) func(*xxh3.Hasher, any) bool {
|
|
switch t.Kind() {
|
|
case reflect.Int,
|
|
reflect.Uint,
|
|
reflect.Uintptr:
|
|
switch unsafe.Sizeof(int(0)) {
|
|
case 4:
|
|
return hash32bit
|
|
case 8:
|
|
return hash64bit
|
|
default:
|
|
panic("unexpected platform int size")
|
|
}
|
|
|
|
case reflect.Int8,
|
|
reflect.Uint8:
|
|
return hash8bit
|
|
|
|
case reflect.Int16,
|
|
reflect.Uint16:
|
|
return hash16bit
|
|
|
|
case reflect.Int32,
|
|
reflect.Uint32,
|
|
reflect.Float32:
|
|
return hash32bit
|
|
|
|
case reflect.Int64,
|
|
reflect.Uint64,
|
|
reflect.Float64,
|
|
reflect.Complex64:
|
|
return hash64bit
|
|
|
|
case reflect.String:
|
|
return hashstring
|
|
|
|
case reflect.Pointer:
|
|
switch t.Elem().Kind() {
|
|
case reflect.Int,
|
|
reflect.Uint,
|
|
reflect.Uintptr:
|
|
switch unsafe.Sizeof(int(0)) {
|
|
case 4:
|
|
return hash32bitptr
|
|
case 8:
|
|
return hash64bitptr
|
|
default:
|
|
panic("unexpected platform int size")
|
|
}
|
|
|
|
case reflect.Int8,
|
|
reflect.Uint8:
|
|
return hash8bitptr
|
|
|
|
case reflect.Int16,
|
|
reflect.Uint16:
|
|
return hash16bitptr
|
|
|
|
case reflect.Int32,
|
|
reflect.Uint32,
|
|
reflect.Float32:
|
|
return hash32bitptr
|
|
|
|
case reflect.Int64,
|
|
reflect.Uint64,
|
|
reflect.Float64,
|
|
reflect.Complex64:
|
|
return hash64bitptr
|
|
|
|
case reflect.String:
|
|
return hashstringptr
|
|
}
|
|
|
|
case reflect.Slice:
|
|
switch t.Elem().Kind() {
|
|
case reflect.Int,
|
|
reflect.Uint,
|
|
reflect.Uintptr:
|
|
switch unsafe.Sizeof(int(0)) {
|
|
case 4:
|
|
return hash32bitslice
|
|
case 8:
|
|
return hash64bitslice
|
|
default:
|
|
panic("unexpected platform int size")
|
|
}
|
|
|
|
case reflect.Int8,
|
|
reflect.Uint8:
|
|
return hash8bitslice
|
|
|
|
case reflect.Int16,
|
|
reflect.Uint16:
|
|
return hash16bitslice
|
|
|
|
case reflect.Int32,
|
|
reflect.Uint32,
|
|
reflect.Float32:
|
|
return hash32bitslice
|
|
|
|
case reflect.Int64,
|
|
reflect.Uint64,
|
|
reflect.Float64,
|
|
reflect.Complex64:
|
|
return hash64bitslice
|
|
|
|
case reflect.String:
|
|
return hashstringslice
|
|
}
|
|
}
|
|
switch {
|
|
case t.Implements(reflect.TypeOf((*interface{ MarshalBinary() ([]byte, error) })(nil)).Elem()):
|
|
return hashbinarymarshaler
|
|
|
|
case t.Implements(reflect.TypeOf((*interface{ Bytes() []byte })(nil)).Elem()):
|
|
return hashbytesmethod
|
|
|
|
case t.Implements(reflect.TypeOf((*interface{ String() string })(nil)).Elem()):
|
|
return hashstringmethod
|
|
|
|
case t.Implements(reflect.TypeOf((*interface{ MarshalText() ([]byte, error) })(nil)).Elem()):
|
|
return hashtextmarshaler
|
|
|
|
case t.Implements(reflect.TypeOf((*interface{ MarshalJSON() ([]byte, error) })(nil)).Elem()):
|
|
return hashjsonmarshaler
|
|
}
|
|
panic("unhashable type")
|
|
}
|
|
|
|
func hash8bit(h *xxh3.Hasher, a any) bool {
|
|
u := *(*uint8)(data_ptr(a))
|
|
_, _ = h.Write([]byte{u})
|
|
return u == 0
|
|
}
|
|
|
|
func hash8bitptr(h *xxh3.Hasher, a any) bool {
|
|
u := (*uint8)(data_ptr(a))
|
|
if u == nil {
|
|
_, _ = h.Write([]byte{
|
|
0,
|
|
})
|
|
return true
|
|
} else {
|
|
_, _ = h.Write([]byte{
|
|
1,
|
|
byte(*u),
|
|
})
|
|
return false
|
|
}
|
|
}
|
|
|
|
func hash8bitslice(h *xxh3.Hasher, a any) bool {
|
|
b := *(*[]byte)(data_ptr(a))
|
|
_, _ = h.Write(b)
|
|
return b == nil
|
|
}
|
|
|
|
func hash16bit(h *xxh3.Hasher, a any) bool {
|
|
u := *(*uint16)(data_ptr(a))
|
|
_, _ = h.Write([]byte{
|
|
byte(u),
|
|
byte(u >> 8),
|
|
})
|
|
return u == 0
|
|
}
|
|
|
|
func hash16bitptr(h *xxh3.Hasher, a any) bool {
|
|
u := (*uint16)(data_ptr(a))
|
|
if u == nil {
|
|
_, _ = h.Write([]byte{
|
|
0,
|
|
})
|
|
return true
|
|
} else {
|
|
_, _ = h.Write([]byte{
|
|
1,
|
|
byte(*u),
|
|
byte(*u >> 8),
|
|
})
|
|
return false
|
|
}
|
|
}
|
|
|
|
func hash16bitslice(h *xxh3.Hasher, a any) bool {
|
|
u := *(*[]uint16)(data_ptr(a))
|
|
for i := range u {
|
|
_, _ = h.Write([]byte{
|
|
byte(u[i]),
|
|
byte(u[i] >> 8),
|
|
})
|
|
}
|
|
return u == nil
|
|
}
|
|
|
|
func hash32bit(h *xxh3.Hasher, a any) bool {
|
|
u := *(*uint32)(data_ptr(a))
|
|
_, _ = h.Write([]byte{
|
|
byte(u),
|
|
byte(u >> 8),
|
|
byte(u >> 16),
|
|
byte(u >> 24),
|
|
})
|
|
return u == 0
|
|
}
|
|
|
|
func hash32bitptr(h *xxh3.Hasher, a any) bool {
|
|
u := (*uint32)(data_ptr(a))
|
|
if u == nil {
|
|
_, _ = h.Write([]byte{
|
|
0,
|
|
})
|
|
return true
|
|
} else {
|
|
_, _ = h.Write([]byte{
|
|
1,
|
|
byte(*u),
|
|
byte(*u >> 8),
|
|
byte(*u >> 16),
|
|
byte(*u >> 24),
|
|
})
|
|
return false
|
|
}
|
|
}
|
|
|
|
func hash32bitslice(h *xxh3.Hasher, a any) bool {
|
|
u := *(*[]uint32)(data_ptr(a))
|
|
for i := range u {
|
|
_, _ = h.Write([]byte{
|
|
byte(u[i]),
|
|
byte(u[i] >> 8),
|
|
byte(u[i] >> 16),
|
|
byte(u[i] >> 24),
|
|
})
|
|
}
|
|
return u == nil
|
|
}
|
|
|
|
func hash64bit(h *xxh3.Hasher, a any) bool {
|
|
u := *(*uint64)(data_ptr(a))
|
|
_, _ = h.Write([]byte{
|
|
byte(u),
|
|
byte(u >> 8),
|
|
byte(u >> 16),
|
|
byte(u >> 24),
|
|
byte(u >> 32),
|
|
byte(u >> 40),
|
|
byte(u >> 48),
|
|
byte(u >> 56),
|
|
})
|
|
return u == 0
|
|
}
|
|
|
|
func hash64bitptr(h *xxh3.Hasher, a any) bool {
|
|
u := (*uint64)(data_ptr(a))
|
|
if u == nil {
|
|
_, _ = h.Write([]byte{
|
|
0,
|
|
})
|
|
return true
|
|
} else {
|
|
_, _ = h.Write([]byte{
|
|
1,
|
|
byte(*u),
|
|
byte(*u >> 8),
|
|
byte(*u >> 16),
|
|
byte(*u >> 24),
|
|
byte(*u >> 32),
|
|
byte(*u >> 40),
|
|
byte(*u >> 48),
|
|
byte(*u >> 56),
|
|
})
|
|
return false
|
|
}
|
|
}
|
|
|
|
func hash64bitslice(h *xxh3.Hasher, a any) bool {
|
|
u := *(*[]uint64)(data_ptr(a))
|
|
for i := range u {
|
|
_, _ = h.Write([]byte{
|
|
byte(u[i]),
|
|
byte(u[i] >> 8),
|
|
byte(u[i] >> 16),
|
|
byte(u[i] >> 24),
|
|
byte(u[i] >> 32),
|
|
byte(u[i] >> 40),
|
|
byte(u[i] >> 48),
|
|
byte(u[i] >> 56),
|
|
})
|
|
}
|
|
return u == nil
|
|
}
|
|
|
|
func hashstring(h *xxh3.Hasher, a any) bool {
|
|
s := *(*string)(data_ptr(a))
|
|
_, _ = h.WriteString(s)
|
|
return s == ""
|
|
}
|
|
|
|
func hashstringptr(h *xxh3.Hasher, a any) bool {
|
|
s := (*string)(data_ptr(a))
|
|
if s == nil {
|
|
_, _ = h.Write([]byte{
|
|
0,
|
|
})
|
|
return true
|
|
} else {
|
|
_, _ = h.Write([]byte{
|
|
1,
|
|
})
|
|
_, _ = h.WriteString(*s)
|
|
return false
|
|
}
|
|
}
|
|
|
|
func hashstringslice(h *xxh3.Hasher, a any) bool {
|
|
s := *(*[]string)(data_ptr(a))
|
|
for i := range s {
|
|
_, _ = h.WriteString(s[i])
|
|
}
|
|
return s == nil
|
|
}
|
|
|
|
func hashbinarymarshaler(h *xxh3.Hasher, a any) bool {
|
|
i := a.(interface{ MarshalBinary() ([]byte, error) })
|
|
b, _ := i.MarshalBinary()
|
|
_, _ = h.Write(b)
|
|
return b == nil
|
|
}
|
|
|
|
func hashbytesmethod(h *xxh3.Hasher, a any) bool {
|
|
i := a.(interface{ Bytes() []byte })
|
|
b := i.Bytes()
|
|
_, _ = h.Write(b)
|
|
return b == nil
|
|
}
|
|
|
|
func hashstringmethod(h *xxh3.Hasher, a any) bool {
|
|
i := a.(interface{ String() string })
|
|
s := i.String()
|
|
_, _ = h.WriteString(s)
|
|
return s == ""
|
|
}
|
|
|
|
func hashtextmarshaler(h *xxh3.Hasher, a any) bool {
|
|
i := a.(interface{ MarshalText() ([]byte, error) })
|
|
b, _ := i.MarshalText()
|
|
_, _ = h.Write(b)
|
|
return b == nil
|
|
}
|
|
|
|
func hashjsonmarshaler(h *xxh3.Hasher, a any) bool {
|
|
i := a.(interface{ MarshalJSON() ([]byte, error) })
|
|
b, _ := i.MarshalJSON()
|
|
_, _ = h.Write(b)
|
|
return b == nil
|
|
}
|