prettify encoder/decoder/muxer/... list extraction

Originally committed as revision 12127 to svn://svn.ffmpeg.org/ffmpeg/trunk

configure

@@ -949,15 +949,22 @@ fi
 
 FFMPEG_CONFIGURATION="$@"
 
-ENCODER_LIST=`sed -n 's/^[^#]*ENC.*(.*, *\(.*\)).*/\1_encoder/p' "$source_path/libavcodec/allcodecs.c"`
-DECODER_LIST=`sed -n 's/^[^#]*DEC.*(.*, *\(.*\)).*/\1_decoder/p' "$source_path/libavcodec/allcodecs.c"`
-PARSER_LIST=`sed -n 's/^[^#]*PARSER.*(.*, *\(.*\)).*/\1_parser/p' "$source_path/libavcodec/allcodecs.c"`
-BSF_LIST=`sed -n 's/^[^#]*BSF.*(.*, *\(.*\)).*/\1_bsf/p' "$source_path/libavcodec/allcodecs.c"`
-MUXER_LIST=`sed -n 's/^[^#]*_MUX.*(.*, *\(.*\)).*/\1_muxer/p' "$source_path/libavformat/allformats.c"`
-DEMUXER_LIST=`sed -n 's/^[^#]*DEMUX.*(.*, *\(.*\)).*/\1_demuxer/p' "$source_path/libavformat/allformats.c"`
-OUTDEV_LIST=`sed -n 's/^[^#]*_MUX.*(.*, *\(.*\)).*/\1_muxer/p' "$source_path/libavdevice/alldevices.c"`
-INDEV_LIST=`sed -n 's/^[^#]*DEMUX.*(.*, *\(.*\)).*/\1_demuxer/p' "$source_path/libavdevice/alldevices.c"`
-PROTOCOL_LIST=`sed -n 's/^[^#]*PROTOCOL.*(.*, *\(.*\)).*/\1_protocol/p' "$source_path/libavformat/allformats.c"`
+find_things(){
+    thing=$1
+    pattern=$2
+    file=$source_path/$3
+    sed -n "s/^[^#]*$pattern.*(.*, *\\(.*\\)).*/\\1_$thing/p" "$file"
+}
+
+ENCODER_LIST=$(find_things  encoder  ENC      libavcodec/allcodecs.c)
+DECODER_LIST=$(find_things  decoder  DEC      libavcodec/allcodecs.c)
+PARSER_LIST=$(find_things   parser   PARSER   libavcodec/allcodecs.c)
+BSF_LIST=$(find_things      bsf      BSF      libavcodec/allcodecs.c)
+MUXER_LIST=$(find_things    muxer    _MUX     libavformat/allformats.c)
+DEMUXER_LIST=$(find_things  demuxer  DEMUX    libavformat/allformats.c)
+OUTDEV_LIST=$(find_things   muxer    _MUX     libavdevice/alldevices.c)
+INDEV_LIST=$(find_things    demuxer  DEMUX    libavdevice/alldevices.c)
+PROTOCOL_LIST=$(find_things protocol PROTOCOL libavformat/allformats.c)
 
 enable $ARCH_EXT_LIST \
        $DECODER_LIST \