NETWORKING: Improve libcurl error handling

Error messages for failed requests are now printed as warnings.

3 files changed, 28 insertions, 12 deletions

diff --git a/backends/networking/curl/connectionmanager.cpp b/backends/networking/curl/connectionmanager.cpp
index 34a9701f75..557fcf06eb 100644
--- a/backends/networking/curl/connectionmanager.cpp
+++ b/backends/networking/curl/connectionmanager.cpp
@@ -184,20 +184,19 @@ void ConnectionManager::processTransfers() {
 	int messagesInQueue;
 	CURLMsg *curlMsg;
 	while ((curlMsg = curl_multi_info_read(_multi, &messagesInQueue))) {
-		CURL *easyHandle = curlMsg->easy_handle;
+		if (curlMsg->msg == CURLMSG_DONE) {
+			CURL *easyHandle = curlMsg->easy_handle;
 
-		NetworkReadStream *stream;
-		curl_easy_getinfo(easyHandle, CURLINFO_PRIVATE, &stream);
-		if (stream)
-			stream->finished();
+			NetworkReadStream *stream = nullptr;
+			curl_easy_getinfo(easyHandle, CURLINFO_PRIVATE, &stream);
 
-		if (curlMsg->msg == CURLMSG_DONE) {
-			debug(9, "ConnectionManager: SUCCESS (%d - %s)", curlMsg->data.result, curl_easy_strerror(curlMsg->data.result));
+			if (stream)
+				stream->finished(curlMsg->data.result);
+
+			curl_multi_remove_handle(_multi, easyHandle);
 		} else {
-			warning("ConnectionManager: FAILURE (CURLMsg (%d))", curlMsg->msg);
+			warning("Unknown libcurl message type %d", curlMsg->msg);
 		}
-
-		curl_multi_remove_handle(_multi, easyHandle);
 	}
 }
 
diff --git a/backends/networking/curl/networkreadstream.cpp b/backends/networking/curl/networkreadstream.cpp
index 59d2a5475c..b41a3c37b7 100644
--- a/backends/networking/curl/networkreadstream.cpp
+++ b/backends/networking/curl/networkreadstream.cpp
@@ -26,6 +26,7 @@
 #include "backends/networking/curl/networkreadstream.h"
 #include "backends/networking/curl/connectionmanager.h"
 #include "base/version.h"
+#include "common/debug.h"
 
 namespace Networking {
 
@@ -64,6 +65,7 @@ int NetworkReadStream::curlProgressCallbackOlder(void *p, double dltotal, double
 
 void NetworkReadStream::init(const char *url, curl_slist *headersList, const byte *buffer, uint32 bufferSize, bool uploading, bool usingPatch, bool post) {
 	_eos = _requestComplete = false;
+	_errorBuffer = (char *)calloc(CURL_ERROR_SIZE, 1);
 	_sendingContentsBuffer = nullptr;
 	_sendingContentsSize = _sendingContentsPos = 0;
 	_progressDownloaded = _progressTotal = 0;
@@ -77,6 +79,7 @@ void NetworkReadStream::init(const char *url, curl_slist *headersList, const byt
 	curl_easy_setopt(_easy, CURLOPT_HEADERDATA, this);
 	curl_easy_setopt(_easy, CURLOPT_HEADERFUNCTION, curlHeadersCallback);
 	curl_easy_setopt(_easy, CURLOPT_URL, url);
+	curl_easy_setopt(_easy, CURLOPT_ERRORBUFFER, _errorBuffer);
 	curl_easy_setopt(_easy, CURLOPT_VERBOSE, 0L);
 	curl_easy_setopt(_easy, CURLOPT_FOLLOWLOCATION, 1L); //probably it's OK to have it always on
 	curl_easy_setopt(_easy, CURLOPT_HTTPHEADER, headersList);
@@ -120,6 +123,7 @@ void NetworkReadStream::init(const char *url, curl_slist *headersList, const byt
 
 void NetworkReadStream::init(const char *url, curl_slist *headersList, Common::HashMap<Common::String, Common::String> formFields, Common::HashMap<Common::String, Common::String> formFiles) {
 	_eos = _requestComplete = false;
+	_errorBuffer = (char *)calloc(CURL_ERROR_SIZE, 1);
 	_sendingContentsBuffer = nullptr;
 	_sendingContentsSize = _sendingContentsPos = 0;
 	_progressDownloaded = _progressTotal = 0;
@@ -133,6 +137,7 @@ void NetworkReadStream::init(const char *url, curl_slist *headersList, Common::H
 	curl_easy_setopt(_easy, CURLOPT_HEADERDATA, this);
 	curl_easy_setopt(_easy, CURLOPT_HEADERFUNCTION, curlHeadersCallback);
 	curl_easy_setopt(_easy, CURLOPT_URL, url);
+	curl_easy_setopt(_easy, CURLOPT_ERRORBUFFER, _errorBuffer);
 	curl_easy_setopt(_easy, CURLOPT_VERBOSE, 0L);
 	curl_easy_setopt(_easy, CURLOPT_FOLLOWLOCATION, 1L); //probably it's OK to have it always on
 	curl_easy_setopt(_easy, CURLOPT_HTTPHEADER, headersList);
@@ -205,6 +210,7 @@ NetworkReadStream::~NetworkReadStream() {
 	if (_easy)
 		curl_easy_cleanup(_easy);
 	free(_bufferCopy);
+	free(_errorBuffer);
 }
 
 bool NetworkReadStream::eos() const {
@@ -223,8 +229,18 @@ uint32 NetworkReadStream::read(void *dataPtr, uint32 dataSize) {
 	return actuallyRead;
 }
 
-void NetworkReadStream::finished() {
+void NetworkReadStream::finished(uint32 errorCode) {
 	_requestComplete = true;
+
+	char *url = nullptr;
+	curl_easy_getinfo(_easy, CURLINFO_EFFECTIVE_URL, &url);
+
+	if (errorCode == CURLE_OK) {
+		debug(9, "NetworkReadStream: %s - Request succeeded", url);
+	} else {
+		warning("NetworkReadStream: %s - Request failed (%d - %s)", url, errorCode,
+		        strlen(_errorBuffer) ? _errorBuffer : curl_easy_strerror((CURLcode)errorCode));
+	}
 }
 
 long NetworkReadStream::httpResponseCode() const {
diff --git a/backends/networking/curl/networkreadstream.h b/backends/networking/curl/networkreadstream.h
index 7d19286f85..468fce70a4 100644
--- a/backends/networking/curl/networkreadstream.h
+++ b/backends/networking/curl/networkreadstream.h
@@ -38,6 +38,7 @@ class NetworkReadStream: public Common::ReadStream {
 	CURL *_easy;
 	Common::MemoryReadWriteStream _backingStream;
 	bool _eos, _requestComplete;
+	char *_errorBuffer;
 	const byte *_sendingContentsBuffer;
 	uint32 _sendingContentsSize;
 	uint32 _sendingContentsPos;
@@ -111,7 +112,7 @@ public:
 	 *
 	 * @note It's called on failure too.
 	 */
-	void finished();
+	void finished(uint32 errorCode);
 
 	/**
 	 * Returns HTTP response code from inner CURL handle.