[FFmpeg-devel] [PATCH]lavc/avpacket: Make pkt parameter of av_packet_get_side_data() const

[Carl Eugen Hoyos]

Hi!

I believe adding const to the declaration of av_packet_get_side_data() 
better reflects its intention, also fixes a warning.

Please comment, Carl Eugen
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From a17c4bab8cd21c15e91f5efd03d5900eda29090b Mon Sep 17 00:00:00 2001
From: Carl Eugen Hoyos <cehoyos at ag.or.at>
Date: Sun, 26 Feb 2017 11:39:07 +0100
Subject: [PATCH] lavc/avpacket: Make pkt parameter of
 av_packet_get_side_data() const.
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Reflects the actual code and silences a gcc warning:
libavcodec/utils.c:2102:36: warning: passing argument 1 of ���av_packet_get_side_data��� discards ���const��� qualifier from pointer target type [-Wdiscarded-qualifiers]
---
 libavcodec/avcodec.h  |    6 +++++-
 libavcodec/avpacket.c |    6 +++++-
 libavcodec/version.h  |    3 +++
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 925a8c7..b065309 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -4563,7 +4563,11 @@ int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
  * @param size pointer for side information size to store (optional)
  * @return pointer to data if present or NULL otherwise
  */
-uint8_t* av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
+uint8_t* av_packet_get_side_data(
+#if FF_API_CONST_GET_SIDE_DATA
+const
+#endif
+                                 AVPacket *pkt, enum AVPacketSideDataType type,
                                  int *size);
 
 int av_packet_merge_side_data(AVPacket *pkt);
diff --git a/libavcodec/avpacket.c b/libavcodec/avpacket.c
index 8e028a2..d369526 100644
--- a/libavcodec/avpacket.c
+++ b/libavcodec/avpacket.c
@@ -336,7 +336,11 @@ uint8_t *av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
     return data;
 }
 
-uint8_t *av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
+uint8_t *av_packet_get_side_data(
+#if FF_API_CONST_GET_SIDE_DATA
+const
+#endif
+                                 AVPacket *pkt, enum AVPacketSideDataType type,
                                  int *size)
 {
     int i;
diff --git a/libavcodec/version.h b/libavcodec/version.h
index 6fdc776..59caa1c 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -157,6 +157,9 @@
 #ifndef FF_API_VAAPI_CONTEXT
 #define FF_API_VAAPI_CONTEXT     (LIBAVCODEC_VERSION_MAJOR < 58)
 #endif
+#ifndef FF_API_CONST_GET_SIDE_DATA
+#define FF_API_CONST_GET_SIDE_DATA (LIBAVCODEC_VERSION_MAJOR >= 58)
+#endif
 #ifndef FF_API_AVCTX_TIMEBASE
 #define FF_API_AVCTX_TIMEBASE    (LIBAVCODEC_VERSION_MAJOR < 59)
 #endif
-- 
1.7.10.4