Handle canceled read during sending data over stats channel

An assertion failure would be triggered when the TCP connection
is canceled during sending the data back to the client.

Don't require the state to be `RECV` on non successful read to
gracefully handle canceled TCP connection during the SEND state of the
HTTPD channel.

diff --git a/lib/isc/httpd.c b/lib/isc/httpd.c
index e4c7d716994a177a4c91781a1dcdd217d79c2f6a..ac31b9a23c746501a0f4003497c056db9e292606 100644 (file)
--- a/lib/isc/httpd.c
+++ b/lib/isc/httpd.c
@@ -907,13 +907,14 @@ httpd_request(isc_nmhandle_t *handle, isc_result_t eresult,
 
        httpd = isc_nmhandle_getdata(handle);
 
-       REQUIRE(httpd->state == RECV);
        REQUIRE(httpd->handle == handle);
 
        if (eresult != ISC_R_SUCCESS) {
                goto cleanup_readhandle;
        }
 
+       REQUIRE(httpd->state == RECV);
+
        result = process_request(
                httpd, region == NULL ? &(isc_region_t){ NULL, 0 } : region,
                &buflen);
@@ -1200,7 +1201,6 @@ httpd_senddone(isc_nmhandle_t *handle, isc_result_t result, void *arg) {
        isc_httpd_t *httpd = (isc_httpd_t *)arg;
 
        REQUIRE(VALID_HTTPD(httpd));
-       REQUIRE(httpd->state == SEND);
        REQUIRE(httpd->handle == handle);
 
        isc_buffer_free(&httpd->sendbuffer);
@@ -1227,6 +1227,8 @@ httpd_senddone(isc_nmhandle_t *handle, isc_result_t result, void *arg) {
                goto cleanup_readhandle;
        }
 
+       REQUIRE(httpd->state == SEND);
+
        httpd->state = RECV;
        httpd->sendhandle = NULL;