x google mux change to new compact channel index scheme

Signed-off-by: Andy Green <andy@warmcat.com>

diff --git a/lib/extension-x-google-mux.c b/lib/extension-x-google-mux.c
index d895175..ac5c4d0 100644 (file)
--- a/lib/extension-x-google-mux.c
+++ b/lib/extension-x-google-mux.c
@@ -32,19 +32,33 @@ static int lws_addheader_mux_opcode(unsigned char *pb, int len)
        return pb - start;
 }
 
-static int lws_mux_subcommand_header(int cmd, int channel, unsigned char *pb, int len)
+static int
+lws_mux_subcommand_header(int cmd, int channel, unsigned char *pb, int len)
 {
        unsigned char *start = pb;
 
-       *pb++ = ((channel >> 8) << 3) | cmd;
-       *pb++ = channel;
+       if (channel < 31)
+               *pb++ = (channel << 3) | cmd;
+       else {
+               *pb++ = (31 << 3) | cmd;
+               *pb++ = channel >> 8;
+               *pb++ = channel;
+       }
 
        if (len <= 253)
                *pb++ = len;
        else {
-               *pb++ = 254;
-               *pb++ = len >> 8;
-               *pb++ = len;
+               if (len <= 65535) {
+                       *pb++ = 254;
+                       *pb++ = len >> 8;
+                       *pb++ = len;
+               } else {
+                       *pb++ = 255;
+                       *pb++ = len >> 24;
+                       *pb++ = len >> 16;
+                       *pb++ = len >> 8;
+                       *pb++ = len;
+               }
        }
 
        return pb - start;
@@ -134,15 +148,25 @@ lws_extension_x_google_mux_parser(struct libwebsocket_context *context,
        case LWS_EXT_XGM_STATE__MUX_BLOCK_1:
                muxdebug("LWS_EXT_XGM_STATE__MUX_BLOCK_1: opc=%d\n", c & 7);
                conn->block_subopcode = c & 7;
-               conn->block_subchannel = (c << 5) & ~0xff;
-               conn->state = LWS_EXT_XGM_STATE__MUX_BLOCK_2;
+               conn->block_subchannel = (c >> 3) & ~0x1f;
+               if (conn->block_subchannel != 31)
+                       goto interpret;
+               else
+                       conn->state = LWS_EXT_XGM_STATE__MUX_BLOCK_2;
                break;
 
        case LWS_EXT_XGM_STATE__MUX_BLOCK_2:
+               conn->block_subchannel = c << 8;
+               conn->state = LWS_EXT_XGM_STATE__MUX_BLOCK_3;
+               break;
+
+       case LWS_EXT_XGM_STATE__MUX_BLOCK_3:
                conn->block_subchannel |= c;
+
                muxdebug("LWS_EXT_XGM_STATE__MUX_BLOCK_2: subchannel=%d\n", conn->block_subchannel);
 
-               ongoing_subchannel = ongoing_subchannel;
+interpret:
+               ongoing_subchannel = conn->block_subchannel;
 
                /*
                 * convert the subchannel index to a child wsi

diff --git a/lib/extension-x-google-mux.h b/lib/extension-x-google-mux.h
index 158a2c7..95c0810 100644 (file)
--- a/lib/extension-x-google-mux.h
+++ b/lib/extension-x-google-mux.h
@@ -26,6 +26,7 @@ void muxdebug(const char *format, ...)
 enum lws_ext_x_google_mux__parser_states {
        LWS_EXT_XGM_STATE__MUX_BLOCK_1,
        LWS_EXT_XGM_STATE__MUX_BLOCK_2,
+       LWS_EXT_XGM_STATE__MUX_BLOCK_3,
        LWS_EXT_XGM_STATE__ADDCHANNEL_LEN,
        LWS_EXT_XGM_STATE__ADDCHANNEL_LEN16_1,
        LWS_EXT_XGM_STATE__ADDCHANNEL_LEN16_2,