func (self *Connection) buildFields(result *C.MYSQL_RES) (fields []Field) {
nfields := int(C.mysql_num_fields(result))
cfieldsptr := C.mysql_fetch_fields(result)
cfields := (*[1 << 30]C.MYSQL_FIELD)(unsafe.Pointer(cfieldsptr))
arena := hack.NewStringArena(1024) // prealloc a reasonable amount of space
fields = make([]Field, nfields)
for i := 0; i < nfields; i++ {
length := strlen(cfields[i].name)
fname := (*[1 << 30]byte)(unsafe.Pointer(cfields[i].name))[:length]
fields[i].Name = arena.NewString(fname)
fields[i].Type = int64(cfields[i]._type)
}
return fields
}
//获取下一行数据(只用于select语句),
//成功返回errnum=0且row有意义, 否则返回errnum
func (mysql *MySQL) NextRow() (row map[string]string, errnum int) {
if mysql.rs == nil {
if C.mysql_field_count(mysql.my) != 0 {
return nil, 4
}
return nil, 5
}
if mysql.fi == nil {
n := uint(C.mysql_num_fields(mysql.rs))
mysql.fi = make([]string, n)
f := C.mysql_fetch_fields(mysql.rs)
for i, _ := range mysql.fi {
mysql.fi[i] = C.GoString(f.name)
f = C.next_field_name(f)
}
}
r := C.mysql_fetch_row(mysql.rs)
if r == nil {
mysql.errno = 0
return nil, 0
}
row = make(map[string]string)
n := uint(len(mysql.fi))
for i := uint(0); i < n; i++ {
row[mysql.fi[i]] = C.GoString(*r)
r = C.next_field_value(r)
}
mysql.errno = 0
errnum = 0
return
}