Proof of concept for backwards negotiating of formats in Asterisk

gistfile1.txt

--- channels/chan_sip.c	(revision 6270)
+++ channels/chan_sip.c	(working copy)
@@ -7227,6 +7227,18 @@
 			sip_pvt_unlock(p);
 		}
 		break;
+	case AST_FRAME_FORMAT:
+		if(!p->outgoing_call){
+			struct ast_format_cap *tmpcap = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT);
+			ast_format_cap_append(tmpcap, frame->subclass.format, 0);
+			sip_pvt_lock(p);
+			ast_format_cap_replace_from_cap(p->jointcaps, tmpcap, AST_MEDIA_TYPE_UNKNOWN);
+			ast_format_cap_replace_from_cap(p->caps, tmpcap, AST_MEDIA_TYPE_UNKNOWN);
+			sip_pvt_unlock(p);
+			ao2_cleanup(tmpcap);				
+		}
+		return 0;
+		break;
 	default:
 		ast_log(LOG_WARNING, "Can't send %u type frames with SIP write\n", frame->frametype);
 		return 0;
@@ -11179,6 +11191,13 @@
 					}
 				}
 			} else if (ast_format_cmp(format, ast_format_amrwb) == AST_FORMAT_CMP_EQUAL) {
+				if(p->outgoing_call && p->owner){
+					struct ast_frame f = { AST_FRAME_FORMAT };
+					f.subclass.format = format;
+					f.subclass.integer = 0;
+					ast_queue_frame(p->owner, &f);
+				}
+
 				// TODO FIXME - add parameter for this!
 				if (sscanf(fmtp_string, "octet-align=%30u", &octet_align) == 1) {
 					if(octet_align == 1) {
--- apps/app_dial.c	(revision 6252)
+++ apps/app_dial.c	(working copy)
@@ -1529,6 +1517,7 @@
 				}
 				/* Fall through */
 			case AST_FRAME_TEXT:
+			case AST_FRAME_FORMAT:
 				if (single && ast_write(in, f)) {
 					ast_log(LOG_WARNING, "Unable to write frametype: %u\n",
 						f->frametype);
@@ -1624,6 +1613,7 @@
 						goto skip_frame;
 					}
 					/* Fall through */
+				case AST_FRAME_FORMAT:
 				case AST_FRAME_TEXT:
 				case AST_FRAME_DTMF_BEGIN:
 				case AST_FRAME_DTMF_END:
--- include/asterisk/frame.h	(revision 6245)
+++ include/asterisk/frame.h	(working copy)
@@ -127,6 +127,7 @@
 	 * directly into bridges.
 	 */
 	AST_FRAME_BRIDGE_ACTION_SYNC,
+	AST_FRAME_FORMAT,
 };
 #define AST_FRAME_DTMF AST_FRAME_DTMF_END
 
--- main/channel.c	(revision 6245)
+++ main/channel.c	(working copy)
@@ -1473,6 +1473,7 @@
 	case AST_FRAME_IAX:
 	case AST_FRAME_CNG:
 	case AST_FRAME_MODEM:
+	case AST_FRAME_FORMAT:
 		return 0;
 	}
 	return 0;
@@ -2819,6 +2820,7 @@
 				case AST_FRAME_BRIDGE_ACTION_SYNC:
 				case AST_FRAME_NULL:
 				case AST_FRAME_CNG:
+				case AST_FRAME_FORMAT:
 					break;
 				}