gRPC: RST_STREAM(NO_ERROR) handling after "trailer only" responses. Similarly to the problem fixed in 2096b21fcd10 (ticket #1792), when a "trailer only" gRPC response (that is, a response with the END_STREAM flag in the HEADERS frame) was immediately followed by RST_STREAM(NO_ERROR) in the data preread along with the response header, RST_STREAM wasn't properly skipped and caused "upstream rejected request with error 0" errors. Observed with "unknown service" gRPC errors returned by grpc-go. Fix is to set ctx->done if we are going to parse additional data, so the RST_STREAM(NO_ERROR) is properly skipped. Additionally, now ngx_http_grpc_filter() will complain about frames sent for closed stream if there are any.

/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>


ngx_err_t
ngx_create_thread(ngx_tid_t *tid,
    ngx_thread_value_t (__stdcall *func)(void *arg), void *arg, ngx_log_t *log)
{
    u_long     id;
    ngx_err_t  err;

    *tid = CreateThread(NULL, 0, func, arg, 0, &id);

    if (*tid != NULL) {
        ngx_log_error(NGX_LOG_NOTICE, log, 0,
                      "create thread " NGX_TID_T_FMT, id);
        return 0;
    }

    err = ngx_errno;
    ngx_log_error(NGX_LOG_ALERT, log, err, "CreateThread() failed");
    return err;
}