lavf: deprecate av_stream_get_end_pts()

According to its documentation it returns "pts of the last muxed packet
+ its duration", but the value it actually returns right now is
(possibly guessed) dts after muxer-internal bitstream filtering (if
any).

This function was added for ffmpeg.c, but it is not used there anymore.
Since the value it returns is ill-defined and so inappropriate for any
serious use, deprecate it.

doc/APIchanges

@@ -14,6 +14,9 @@ libavutil:     2021-04-27
 
 API changes, most recent first:
 
+2022-08-xx - xxxxxxxxxx - lavf 59 - avformat.h
+  Deprecate av_stream_get_end_pts() without replacement.
+
 2022-08-19 - 352799dca8 - lavc 59.42.102 - codec_id.h
   Deprecate AV_CODEC_ID_AYUV and ayuv decoder/encoder. The rawvideo codec
   and vuya pixel format combination will be used instead from now on.

libavformat/avformat.h

@@ -1121,12 +1121,15 @@ typedef struct AVStream {
 
 struct AVCodecParserContext *av_stream_get_parser(const AVStream *s);
 
+#if FF_API_GET_END_PTS
 /**
  * Returns the pts of the last muxed packet + its duration
  *
  * the retuned value is undefined when used with a demuxer.
  */
+attribute_deprecated
 int64_t    av_stream_get_end_pts(const AVStream *st);
+#endif
 
 #define AV_PROGRAM_RUNNING 1
 

libavformat/mux_utils.c

@@ -29,6 +29,7 @@
 #include "internal.h"
 #include "mux.h"
 
+#if FF_API_GET_END_PTS
 int64_t av_stream_get_end_pts(const AVStream *st)
 {
     if (cffstream(st)->priv_pts) {
@@ -36,6 +37,7 @@ int64_t av_stream_get_end_pts(const AVStream *st)
     } else
         return AV_NOPTS_VALUE;
 }
+#endif
 
 int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id,
                          int std_compliance)

libavformat/version_major.h

@@ -46,6 +46,7 @@
 #define FF_API_AVIOCONTEXT_WRITTEN      (LIBAVFORMAT_VERSION_MAJOR < 60)
 #define FF_HLS_TS_OPTIONS               (LIBAVFORMAT_VERSION_MAJOR < 60)
 #define FF_API_AVSTREAM_CLASS           (LIBAVFORMAT_VERSION_MAJOR > 59)
+#define FF_API_GET_END_PTS              (LIBAVFORMAT_VERSION_MAJOR < 60)
 
 
 #define FF_API_R_FRAME_RATE            1