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) Maxim Dounin
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_DLOPEN_H_INCLUDED_
#define _NGX_DLOPEN_H_INCLUDED_


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


#define ngx_dlopen(path)           dlopen((char *) path, RTLD_NOW | RTLD_GLOBAL)
#define ngx_dlopen_n               "dlopen()"

#define ngx_dlsym(handle, symbol)  dlsym(handle, symbol)
#define ngx_dlsym_n                "dlsym()"

#define ngx_dlclose(handle)        dlclose(handle)
#define ngx_dlclose_n              "dlclose()"


#if (NGX_HAVE_DLOPEN)
char *ngx_dlerror(void);
#endif


#endif /* _NGX_DLOPEN_H_INCLUDED_ */