v811_spc009/external/libwebsockets/minimal-examples/raw/minimal-raw-adopt-tcp

lws minimal ws server raw adopt tcp

This example is only meaningful if you are integrating lws in another app which generates its own connected sockets. In some cases you may want lws to "adopt" the socket.

(If you simply want a connected client raw socket using lws alone, you can just use lws_client_connect_via_info() with info.method = "RAW". http-client/minimal-http-client shows how to do that, just set info.method to "RAW".)

This example demonstrates how to adopt a foreign, connected socket into lws as a raw wsi, bound to a specific lws protocol.

The example connects a socket itself to libwebsockets.org:80, and then has lws adopt it as a raw wsi. The lws protocol writes "GET / HTTP/1.1" to the socket and hexdumps what was sent back.

The socket won't close until the server side times it out, since it's a raw socket that doesn't understand it's looking at http.

build

 $ cmake . && make

usage

 $ ./lws-minimal-raw-adopt-tcp
[2018/03/23 09:03:57:1960] USER: LWS minimal raw adopt tcp
[2018/03/23 09:03:57:1961] NOTICE: Creating Vhost 'default' port 7681, 1 protocols, IPv6 off
[2018/03/23 09:03:57:2079] USER: Starting connect...
[2018/03/23 09:03:57:4963] USER: Connected...
[2018/03/23 09:03:57:4963] USER: LWS_CALLBACK_RAW_ADOPT
[2018/03/23 09:03:57:7842] USER: LWS_CALLBACK_RAW_RX (186)
[2018/03/23 09:03:57:7842] NOTICE: 
[2018/03/23 09:03:57:7842] NOTICE: 0000: 48 54 54 50 2F 31 2E 31 20 33 30 31 20 52 65 64    HTTP/1.1 301 Red
[2018/03/23 09:03:57:7842] NOTICE: 0010: 69 72 65 63 74 0D 0A 73 65 72 76 65 72 3A 20 6C    irect..server: l
[2018/03/23 09:03:57:7842] NOTICE: 0020: 77 73 77 73 0D 0A 53 74 72 69 63 74 2D 54 72 61    wsws..Strict-Tra
[2018/03/23 09:03:57:7843] NOTICE: 0030: 6E 73 70 6F 72 74 2D 53 65 63 75 72 69 74 79 3A    nsport-Security:
[2018/03/23 09:03:57:7843] NOTICE: 0040: 20 6D 61 78 2D 61 67 65 3D 31 35 37 36 38 30 30     max-age=1576800
[2018/03/23 09:03:57:7843] NOTICE: 0050: 30 20 3B 20 69 6E 63 6C 75 64 65 53 75 62 44 6F    0 ; includeSubDo
[2018/03/23 09:03:57:7843] NOTICE: 0060: 6D 61 69 6E 73 0D 0A 6C 6F 63 61 74 69 6F 6E 3A    mains..location:
[2018/03/23 09:03:57:7843] NOTICE: 0070: 20 68 74 74 70 73 3A 2F 2F 6C 69 62 77 65 62 73     https://libwebs
[2018/03/23 09:03:57:7843] NOTICE: 0080: 6F 63 6B 65 74 73 2E 6F 72 67 0D 0A 63 6F 6E 74    ockets.org..cont
[2018/03/23 09:03:57:7843] NOTICE: 0090: 65 6E 74 2D 74 79 70 65 3A 20 74 65 78 74 2F 68    ent-type: text/h
[2018/03/23 09:03:57:7843] NOTICE: 00A0: 74 6D 6C 0D 0A 63 6F 6E 74 65 6E 74 2D 6C 65 6E    tml..content-len
[2018/03/23 09:03:57:7843] NOTICE: 00B0: 67 74 68 3A 20 30 0D 0A 0D 0A                      gth: 0....      
[2018/03/23 09:03:57:7843] NOTICE: 
[2018/03/23 09:04:03:3627] USER: LWS_CALLBACK_RAW_CLOSE

Note the example does everything itself, after 5s idle the remote server closes the connection after which the example continues until you ^C it.