1
0
forked from um/cli
cli/algo/qmc/qmc_footer.go

64 lines
1.7 KiB
Go

package qmc
import (
"encoding/binary"
"fmt"
"io"
)
type qqMusicTagMusicEx struct {
songid uint32 // Song ID
unknown_1 uint32 // unused & unknown
unknown_2 uint32 // unused & unknown
mid string // Media ID
mediafile string // real file name
unknown_3 uint32 // unused; uninitialized memory?
sizeof_struct uint32 // 19.57: fixed value: 0xC0
version uint32 // 19.57: fixed value: 0x01
tag_magic []byte // fixed value "musicex\0" (8 bytes)
}
func (tag *qqMusicTagMusicEx) Read(raw io.ReadSeeker) (int64, error) {
_, err := raw.Seek(-16, io.SeekEnd)
if err != nil {
return 0, fmt.Errorf("musicex seek error: %w", err)
}
footerBuf := make([]byte, 4)
footerBuf, err = io.ReadAll(io.LimitReader(raw, 4))
if err != nil {
return 0, fmt.Errorf("get musicex error: %w", err)
}
footerLen := int64(binary.LittleEndian.Uint32(footerBuf))
audioLen, err := raw.Seek(-footerLen, io.SeekEnd)
buf, err := io.ReadAll(io.LimitReader(raw, audioLen))
if err != nil {
return 0, err
}
tag.songid = binary.LittleEndian.Uint32(buf[0:4])
tag.unknown_1 = binary.LittleEndian.Uint32(buf[4:8])
tag.unknown_2 = binary.LittleEndian.Uint32(buf[8:12])
for i := 0; i < 30; i++ {
u := binary.LittleEndian.Uint16(buf[12+i*2 : 12+(i+1)*2])
if u != 0 {
tag.mid += string(u)
}
}
for i := 0; i < 50; i++ {
u := binary.LittleEndian.Uint16(buf[72+i*2 : 72+(i+1)*2])
if u != 0 {
tag.mediafile += string(u)
}
}
tag.unknown_3 = binary.LittleEndian.Uint32(buf[173:177])
tag.sizeof_struct = binary.LittleEndian.Uint32(buf[177:181])
tag.version = binary.LittleEndian.Uint32(buf[181:185])
tag.tag_magic = buf[185:193]
return audioLen, nil
}