Function InterceptInterceptHook

example/plugins/c-api/intercept/intercept.cc:276–512

Handle events from TSHttpTxnServerIntercept. The intercept starts with TS_EVENT_NET_ACCEPT, and then continues with TSVConn events.

// starts with TS_EVENT_NET_ACCEPT, and then continues with
// TSVConn events.
static int
InterceptInterceptHook(TSCont contp, TSEvent event, void *edata)
{
  argument_type arg(edata);

  VDEBUG("contp=%p, event=%s (%d), edata=%p", contp, TSHttpEventNameLookup(event), event, arg.ptr);

  switch (event) {
  case TS_EVENT_NET_ACCEPT: {
    // Set up the server intercept. We have the original
    // TSHttpTxn from the continuation. We need to connect to the
    // real origin and get ready to shuffle data around.
    char            buf[INET_ADDRSTRLEN];
    socket_type     addr;
    argument_type   cdata(TSContDataGet(contp));
    InterceptState *istate = new InterceptState();
    int             fd     = -1;

    // This event is delivered by the continuation that we
    // attached in InterceptTxnHook, so the continuation data is
    // the TSHttpTxn pointer.
    VDEBUG("allocated server intercept state istate=%p for txn=%p", istate, cdata.txn);

    // Set up a connection to our real origin, which will be
    // 127.0.0.1:$PORT.
    memset(&addr, 0, sizeof(addr));
    addr.sin.sin_family      = AF_INET;
    addr.sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK); // XXX config option
    addr.sin.sin_port        = htons(PORT);            // XXX config option

    // Normally, we would use TSNetConnect to connect to a secondary service, but to demonstrate
    // the use of TSVConnFdCreate, we do a blocking connect inline. This it not recommended for
    // production plugins, since it might block an event thread for an arbitrary time.
    fd = ::socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
    TSReleaseAssert(fd != -1);

    if (::connect(fd, &addr.sa, sizeof(addr.sin)) == -1) {
      // We failed to connect to the intercepted origin. Abort the
      // server intercept since we cannot handle it.
      VDEBUG("connect failed with %s (%d)", strerror(errno), errno);
      TSVConnAbort(arg.vc, TS_VC_CLOSE_ABORT);

      delete istate;
      TSContDestroy(contp);

      ::close(fd);
      return TS_EVENT_NONE;
    }

    if ((istate->server.vc = TSVConnFdCreate(fd)) == nullptr) {
      VDEBUG("TSVconnFdCreate() failed");
      TSVConnAbort(arg.vc, TS_VC_CLOSE_ABORT);

      delete istate;
      TSContDestroy(contp);

      ::close(fd);
      return TS_EVENT_NONE;