[Tarantool-patches] [PATCH v3 3/4] http: enrich httpc_request with curl error message buffer

[Ilya Kosarev <i.kosarev@tarantool.org>]

When processing curl request error code, we are collecting error
message using curl_easy_strerror. Now we are providing more info
in errmsg, which is obtained using curl_easy_setopt with
CURLOPT_ERRORBUFFER option.

Closes #4578

@TarantoolBot document
Title: http: new field in client_object:request return table
Update the documentation for client_object:request method to reflect
new field errmsg in return table. It contains extended curl request
error message obtained using CURLOPT_ERRORBUFFER option.
See https://curl.haxx.se/libcurl/c/CURLOPT_ERRORBUFFER.html
---
 src/httpc.c     | 1 +
 src/httpc.h     | 5 +++++
 src/lua/httpc.c | 4 ++++
 3 files changed, 10 insertions(+)

diff --git a/src/httpc.c b/src/httpc.c
index 22b54d16a..b493a8498 100644
--- a/src/httpc.c
+++ b/src/httpc.c
@@ -398,6 +398,7 @@ httpc_execute(struct httpc_request *req, double timeout)
 	curl_easy_setopt(req->curl_request.easy, CURLOPT_HEADERDATA, (void *) req);
 	curl_easy_setopt(req->curl_request.easy, CURLOPT_PRIVATE, (void *) &req->curl_request);
 	curl_easy_setopt(req->curl_request.easy, CURLOPT_HTTPHEADER, req->headers);
+	curl_easy_setopt(req->curl_request.easy, CURLOPT_ERRORBUFFER, req->errmsg);
 
 	++env->stat.total_requests;
 
diff --git a/src/httpc.h b/src/httpc.h
index f710b3d13..145b59929 100644
--- a/src/httpc.h
+++ b/src/httpc.h
@@ -105,6 +105,11 @@ struct httpc_request {
 	int status;
 	/** Error message */
 	const char *reason;
+	/**
+	 * Buffer for error message obtained using
+	 * CURLOPT_ERRORBUFFER option.
+	 */
+        const char errmsg[CURL_ERROR_SIZE];
 	/** buffer of headers */
 	struct region resp_headers;
 	/** buffer of body */
diff --git a/src/lua/httpc.c b/src/lua/httpc.c
index 6ed4eb788..9fb8e4801 100644
--- a/src/lua/httpc.c
+++ b/src/lua/httpc.c
@@ -335,6 +335,10 @@ luaT_httpc_request(lua_State *L)
 	lua_pushstring(L, req->reason);
 	lua_settable(L, -3);
 
+	lua_pushstring(L, "errmsg");
+	lua_pushstring(L, req->errmsg);
+	lua_settable(L, -3);
+
 	size_t headers_len = region_used(&req->resp_headers);
 	if (headers_len > 0) {
 		char *headers = region_join(&req->resp_headers, headers_len);
-- 
2.17.1