mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-11-10 04:57:26 +01:00
112 lines
2.1 KiB
Go
112 lines
2.1 KiB
Go
// Copyright 2017 The Ebiten Authors
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
// +build !js
|
|
|
|
package mp3
|
|
|
|
// #include "pdmp3.h"
|
|
import "C"
|
|
|
|
import (
|
|
"errors"
|
|
"io"
|
|
"unsafe"
|
|
)
|
|
|
|
const (
|
|
eof = 0xffffffff
|
|
)
|
|
|
|
var (
|
|
reader io.Reader
|
|
readerCache []uint8
|
|
readerPos int
|
|
readerEOF bool
|
|
writer io.Writer
|
|
)
|
|
|
|
func getByte() (uint8, error) {
|
|
for len(readerCache) == 0 && !readerEOF {
|
|
buf := make([]uint8, 4096)
|
|
n, err := reader.Read(buf)
|
|
readerCache = append(readerCache, buf[:n]...)
|
|
if err != nil {
|
|
if err == io.EOF {
|
|
readerEOF = true
|
|
} else {
|
|
return 0, err
|
|
}
|
|
}
|
|
}
|
|
if len(readerCache) == 0 {
|
|
return 0, io.EOF
|
|
}
|
|
b := readerCache[0]
|
|
readerCache = readerCache[1:]
|
|
readerPos++
|
|
return b, nil
|
|
}
|
|
|
|
func getBytes(buf []int) (int, error) {
|
|
for i := range buf {
|
|
v, err := getByte()
|
|
buf[i] = int(v)
|
|
if err == io.EOF {
|
|
return i, io.EOF
|
|
}
|
|
}
|
|
return len(buf), nil
|
|
}
|
|
|
|
//export Get_Filepos
|
|
func Get_Filepos() C.unsigned {
|
|
if len(readerCache) == 0 && readerEOF {
|
|
return eof
|
|
}
|
|
return C.unsigned(readerPos)
|
|
}
|
|
|
|
//export writeToWriter
|
|
func writeToWriter(data unsafe.Pointer, size C.int) C.size_t {
|
|
buf := C.GoBytes(data, size)
|
|
n, err := writer.Write(buf)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
return C.size_t(n)
|
|
}
|
|
|
|
var g_error error
|
|
|
|
func decode(r io.Reader, w io.Writer) error {
|
|
reader = r
|
|
writer = w
|
|
for Get_Filepos() != eof {
|
|
err := readFrame()
|
|
if err == nil {
|
|
C.Decode_L3()
|
|
continue
|
|
}
|
|
if Get_Filepos() == eof {
|
|
break
|
|
}
|
|
if err != nil {
|
|
return err
|
|
}
|
|
return errors.New("mp3: not enough maindata to decode frame")
|
|
}
|
|
return g_error
|
|
}
|