orm/lib/pq/buf.go
snoop e7676fbf33 changed
path
2016-11-08 16:43:47 +09:00

92 lines
1.6 KiB
Go

package pq
import (
"bytes"
"encoding/binary"
"loafle.com/commons/orm/lib/pq/oid"
)
type readBuf []byte
func (b *readBuf) int32() (n int) {
n = int(int32(binary.BigEndian.Uint32(*b)))
*b = (*b)[4:]
return
}
func (b *readBuf) oid() (n oid.Oid) {
n = oid.Oid(binary.BigEndian.Uint32(*b))
*b = (*b)[4:]
return
}
// N.B: this is actually an unsigned 16-bit integer, unlike int32
func (b *readBuf) int16() (n int) {
n = int(binary.BigEndian.Uint16(*b))
*b = (*b)[2:]
return
}
func (b *readBuf) string() string {
i := bytes.IndexByte(*b, 0)
if i < 0 {
errorf("invalid message format; expected string terminator")
}
s := (*b)[:i]
*b = (*b)[i+1:]
return string(s)
}
func (b *readBuf) next(n int) (v []byte) {
v = (*b)[:n]
*b = (*b)[n:]
return
}
func (b *readBuf) byte() byte {
return b.next(1)[0]
}
type writeBuf struct {
buf []byte
pos int
}
func (b *writeBuf) int32(n int) {
x := make([]byte, 4)
binary.BigEndian.PutUint32(x, uint32(n))
b.buf = append(b.buf, x...)
}
func (b *writeBuf) int16(n int) {
x := make([]byte, 2)
binary.BigEndian.PutUint16(x, uint16(n))
b.buf = append(b.buf, x...)
}
func (b *writeBuf) string(s string) {
b.buf = append(b.buf, (s + "\000")...)
}
func (b *writeBuf) byte(c byte) {
b.buf = append(b.buf, c)
}
func (b *writeBuf) bytes(v []byte) {
b.buf = append(b.buf, v...)
}
func (b *writeBuf) wrap() []byte {
p := b.buf[b.pos:]
binary.BigEndian.PutUint32(p, uint32(len(p)))
return b.buf
}
func (b *writeBuf) next(c byte) {
p := b.buf[b.pos:]
binary.BigEndian.PutUint32(p, uint32(len(p)))
b.pos = len(b.buf) + 1
b.buf = append(b.buf, c, 0, 0, 0, 0)
}