go-podcast-proxy/mpvconvert.go

package main

import (
    "log"
    "path/filepath"
    "os"
    "unsafe"
)

// #cgo LDFLAGS: -lmpv
// #include <stdlib.h>
// #include <stdio.h>
// #include <mpv/client.h>
// mpv_handle* mpvinit(){
//     return mpv_create();
// }
// int mpvbegin(mpv_handle* mpv, char* src, char* dst) {
//   mpv_set_property_string(mpv, "o", dst);
//   mpv_initialize(mpv);
//   const char *args[3] = {"loadfile", src, NULL};
//   return mpv_command(mpv, args);
// }
// void mpvset(mpv_handle* mpv, char* opt, char* val) {
//   mpv_set_property_string(mpv, opt, val);
// }
// mpv_event* mpvwait(mpv_handle* mpv){
//   return mpv_wait_event(mpv, 0.25);
// }
// void mpvend(mpv_handle* mpv){
//   mpv_destroy(mpv);
// }
import "C"

func (ctx* ServerContext) MPVConvert(source string, destination string, ext string, options []MPVPair) {
    defer ctx.WG.Done()

    dir := filepath.Dir(destination)
    os.MkdirAll(dir, os.ModePerm)

    mpv := C.mpvinit()
    set := func (opt string, val string) {
        copt := C.CString(opt)
        defer C.free(unsafe.Pointer(copt))
        cval := C.CString(val)
        defer C.free(unsafe.Pointer(cval))
        C.mpvset(mpv, copt, cval)
    }

    csrc := C.CString(source)
    defer C.free(unsafe.Pointer(csrc))
    cdst := C.CString(destination)
    defer C.free(unsafe.Pointer(cdst))

    for _, p := range options {
        set(p.Option, p.Value)
    }

    r := C.mpvbegin(mpv, csrc, cdst)
    if r!=0 {
        log.Println("mpv error (", source, ", ", destination, ", ", ext, "): ", r)
    }
    for C.mpvwait(mpv).event_id!=C.MPV_EVENT_END_FILE {
        if !ctx.IsActive {
            C.mpvend(mpv)
            os.Remove(destination)
            log.Println("mpv cancelled (", source, ", ", destination, ", ", ext, ")")
            return
        }
    }
    log.Println("mpv success (", source, ", ", destination, ", ", ext, ")")
    C.mpvend(mpv)
}