github.com/segmentio/encoding@v0.4.0/proto/size.go (about)

     1  package proto
     2  
     3  import (
     4  	"math/bits"
     5  	"unsafe"
     6  )
     7  
     8  type sizeFunc = func(unsafe.Pointer, flags) int
     9  
    10  func sizeOfVarint(v uint64) int {
    11  	return (bits.Len64(v|1) + 6) / 7
    12  }
    13  
    14  func sizeOfVarintZigZag(v int64) int {
    15  	return sizeOfVarint((uint64(v) << 1) ^ uint64(v>>63))
    16  }
    17  
    18  func sizeOfVarlen(n int) int {
    19  	return sizeOfVarint(uint64(n)) + n
    20  }
    21  
    22  func sizeOfTag(f fieldNumber, t wireType) int {
    23  	return sizeOfVarint(uint64(f)<<3 | uint64(t))
    24  }