ffmpeg: Expose return codes.

ffmpeg/ffmpeg.go

@@ -1,7 +1,6 @@
 package ffmpeg
 
 import (
-	"errors"
 	"github.com/golang/glog"
 	"unsafe"
 )
@@ -11,8 +10,6 @@ import (
 // #include "lpms_ffmpeg.h"
 import "C"
 
-var ErrFFMpegSegmenter = errors.New("FFMpegSegmenterError")
-
 func RTMPToHLS(localRTMPUrl string, outM3U8 string, tmpl string, seglen_secs string) error {
 	inp := C.CString(localRTMPUrl)
 	outp := C.CString(outM3U8)
@@ -24,8 +21,8 @@ func RTMPToHLS(localRTMPUrl string, outM3U8 string, tmpl string, seglen_secs str
 	C.free(unsafe.Pointer(ts_tmpl))
 	C.free(unsafe.Pointer(seglen))
 	if 0 != ret {
-		glog.Infof("RTMP2HLS Transmux Return : %d\n", ret)
-		return ErrFFMpegSegmenter
+		glog.Infof("RTMP2HLS Transmux Return : %v\n", Strerror(ret))
+		return ErrorMap[ret]
 	}
 	return nil
 }

ffmpeg/ffmpeg_errors.go

@@ -0,0 +1,47 @@
+package ffmpeg
+
+// #cgo pkg-config: libavformat
+//#include "ffmpeg_errors.h"
+import "C"
+import (
+	"encoding/binary"
+	"errors"
+	"unsafe"
+)
+
+func error_map() map[int]error {
+	// errs is a []byte , we really need an []int so need to convert
+	errs := C.GoBytes(unsafe.Pointer(&C.ffmpeg_errors), C.sizeof_ffmpeg_errors)
+	m := make(map[int]error)
+	for i := 0; i < len(errs)/C.sizeof_int; i++ {
+		// unsigned -> C 4-byte signed int -> golang nativeint
+		// golang nativeint is usually 8 bytes on 64bit, so intermediate cast is
+		// needed to preserve sign
+		v := int(int32(binary.LittleEndian.Uint32(errs[i*C.sizeof_int : (i+1)*C.sizeof_int])))
+		m[v] = errors.New(Strerror(v))
+	}
+	for i := -255; i < 0; i++ {
+		v := Strerror(i)
+		if "UNKNOWN_ERROR" != v {
+			m[i] = errors.New(v)
+		}
+	}
+
+	return m
+}
+
+var ErrorMap = error_map()
+
+// Use of this source code is governed by a MIT license that can be found in the LICENSE file.
+// Corbatto (luca@corbatto.de)
+
+// Strerror returns a descriptive string of the given return code.
+//
+// C-Function: av_strerror
+func Strerror(errnum int) string {
+	buf := make([]C.char, C.ffmpeg_AV_ERROR_MAX_STRING_SIZE)
+	if C.av_strerror(C.int(errnum), (*C.char)(unsafe.Pointer(&buf[0])), C.size_t(len(buf))) != 0 {
+		return "UNKNOWN_ERROR"
+	}
+	return C.GoString((*C.char)(unsafe.Pointer(&buf[0])))
+}

ffmpeg/ffmpeg_errors.h

@@ -0,0 +1,38 @@
+#ifndef FFMPEG_ERRORS_H
+#define FFMPEG_ERRORS_H
+
+#include <libavutil/error.h>
+#include <libavutil/avutil.h>
+
+int ffmpeg_errors[] = {
+  AVERROR_BSF_NOT_FOUND,
+  AVERROR_BUG,
+  AVERROR_BUFFER_TOO_SMALL,
+  AVERROR_DECODER_NOT_FOUND,
+  AVERROR_DEMUXER_NOT_FOUND,
+  AVERROR_ENCODER_NOT_FOUND,
+  AVERROR_EOF,
+  AVERROR_EXIT,
+  AVERROR_EXTERNAL,
+  AVERROR_FILTER_NOT_FOUND,
+  AVERROR_INVALIDDATA,
+  AVERROR_MUXER_NOT_FOUND,
+  AVERROR_OPTION_NOT_FOUND,
+  AVERROR_PATCHWELCOME,
+  AVERROR_PROTOCOL_NOT_FOUND,
+  AVERROR_STREAM_NOT_FOUND,
+  AVERROR_UNKNOWN,
+  AVERROR_EXPERIMENTAL,
+  AVERROR_INPUT_CHANGED,
+  AVERROR_OUTPUT_CHANGED,
+  AVERROR_HTTP_BAD_REQUEST,
+  AVERROR_HTTP_UNAUTHORIZED,
+  AVERROR_HTTP_FORBIDDEN,
+  AVERROR_HTTP_NOT_FOUND,
+  AVERROR_HTTP_OTHER_4XX,
+  AVERROR_HTTP_SERVER_ERROR
+};
+
+const int ffmpeg_AV_ERROR_MAX_STRING_SIZE = AV_ERROR_MAX_STRING_SIZE;
+
+#endif