rtpdec: Don't pass non-const pointers to fmtp attribute parsing functions

This makes it clear that the individual parsing functions can't
touch the parsed out value.
Signed-off-by: Martin Storsjö <martin@martin.st>

libavformat/rtpdec.c

@@ -844,7 +844,7 @@ int ff_parse_fmtp(AVFormatContext *s,
                   int (*parse_fmtp)(AVFormatContext *s,
                                     AVStream *stream,
                                     PayloadContext *data,
-                                    char *attr, char *value))
+                                    const char *attr, const char *value))
 {
     char attr[256];
     char *value;

libavformat/rtpdec.h

@@ -207,7 +207,7 @@ int ff_parse_fmtp(AVFormatContext *s,
                   int (*parse_fmtp)(AVFormatContext *s,
                                     AVStream *stream,
                                     PayloadContext *data,
-                                    char *attr, char *value));
+                                    const char *attr, const char *value));
 
 void ff_register_rtp_dynamic_payload_handlers(void);
 

libavformat/rtpdec_amr.c

@@ -137,7 +137,7 @@ static int amr_handle_packet(AVFormatContext *ctx, PayloadContext *data,
 
 static int amr_parse_fmtp(AVFormatContext *s,
                           AVStream *stream, PayloadContext *data,
-                          char *attr, char *value)
+                          const char *attr, const char *value)
 {
     /* Some AMR SDP configurations contain "octet-align", without
      * the trailing =1. Therefore, if the value is empty,
@@ -146,7 +146,7 @@ static int amr_parse_fmtp(AVFormatContext *s,
     if (!strcmp(value, "")) {
         av_log(s, AV_LOG_WARNING, "AMR fmtp attribute %s had "
                                   "nonstandard empty value\n", attr);
-        strcpy(value, "1");
+        value = "1";
     }
     if (!strcmp(attr, "octet-align"))
         data->octet_align = atoi(value);

libavformat/rtpdec_dv.c

@@ -48,7 +48,7 @@ static av_cold void dv_free_context(PayloadContext *data)
 static av_cold int dv_sdp_parse_fmtp_config(AVFormatContext *s,
                                             AVStream *stream,
                                             PayloadContext *dv_data,
-                                            char *attr, char *value)
+                                            const char *attr, const char *value)
 {
     /* does the DV stream include audio? */
     if (!strcmp(attr, "audio") && !strcmp(value, "bundled"))

libavformat/rtpdec_h264.c

@@ -144,7 +144,7 @@ int ff_h264_parse_sprop_parameter_sets(AVFormatContext *s,
 static int sdp_parse_fmtp_config_h264(AVFormatContext *s,
                                       AVStream *stream,
                                       PayloadContext *h264_data,
-                                      char *attr, char *value)
+                                      const char *attr, const char *value)
 {
     AVCodecContext *codec = stream->codec;
 

libavformat/rtpdec_hevc.c

@@ -46,7 +46,7 @@ static const uint8_t start_sequence[] = { 0x00, 0x00, 0x00, 0x01 };
 static av_cold int hevc_sdp_parse_fmtp_config(AVFormatContext *s,
                                               AVStream *stream,
                                               PayloadContext *hevc_data,
-                                              char *attr, char *value)
+                                              const char *attr, const char *value)
 {
     /* profile-space: 0-3 */
     /* profile-id: 0-31 */

libavformat/rtpdec_ilbc.c

@@ -25,7 +25,7 @@
 
 static int ilbc_parse_fmtp(AVFormatContext *s,
                            AVStream *stream, PayloadContext *data,
-                           char *attr, char *value)
+                           const char *attr, const char *value)
 {
     if (!strcmp(attr, "mode")) {
         int mode = atoi(value);

libavformat/rtpdec_latm.c

@@ -140,7 +140,7 @@ end:
 
 static int parse_fmtp(AVFormatContext *s,
                       AVStream *stream, PayloadContext *data,
-                      char *attr, char *value)
+                      const char *attr, const char *value)
 {
     int res;
 

libavformat/rtpdec_mpeg4.c

@@ -274,7 +274,7 @@ static int aac_parse_packet(AVFormatContext *ctx, PayloadContext *data,
 
 static int parse_fmtp(AVFormatContext *s,
                       AVStream *stream, PayloadContext *data,
-                      char *attr, char *value)
+                      const char *attr, const char *value)
 {
     AVCodecContext *codec = stream->codec;
     int res, i;

libavformat/rtpdec_xiph.c

@@ -295,7 +295,7 @@ parse_packed_headers(const uint8_t * packed_headers,
 static int xiph_parse_fmtp_pair(AVFormatContext *s,
                                 AVStream* stream,
                                 PayloadContext *xiph_data,
-                                char *attr, char *value)
+                                const char *attr, const char *value)
 {
     AVCodecContext *codec = stream->codec;
     int result = 0;