--- a
+++ b/src/mediaserver/cdplugins/netfetch.h
@@ -0,0 +1,108 @@
+/* Copyright (C) 2017-2018 J.F.Dockes
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the
+ * Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#ifndef _MEDIAFETCH_H_INCLUDED_
+#define _MEDIAFETCH_H_INCLUDED_
+
+#include <functional>
+
+#include "bufxchange.h"
+#include "abuffer.h"
+
+//
+// Wrapper for a network fetch
+//
+// The transfer is aborted when the object is deleted, with proper
+// cleanup.
+//
+// The end of transfer is marked by pushing an empty buffer on the queue
+//
+// All methods are supposedly thread-safe
+class NetFetch {
+public:
+ NetFetch(const std::string& u)
+ : _url(u) {
+ }
+ virtual ~NetFetch() {}
+
+ virtual const std::string& url() {
+ return _url;
+ }
+
+ virtual void setTimeout(int secs) {
+ timeoutsecs = secs;
+ }
+
+ /// Start the transfer to the output queue.
+ virtual bool start(BufXChange<ABuffer*> *queue, uint64_t offset = 0) = 0;
+
+ // Wait for headers. This allows, e.g. doing stuff depending on
+ // content-type before proceeding with the actual data
+ // transfer. May not work exactly the same depending on the
+ // underlaying implementation.
+ virtual bool waitForHeaders(int maxSecs = 0) = 0;
+ // Retrieve header value (after a successful waitForHeaders).
+ virtual bool headerValue(const std::string& nm, std::string& val) = 0;
+
+ // Check if the fetch is done and retrieve the results if it
+ // is. This does not wait, it returns false if the transfer is
+ // still running.
+ // The pointers can be set to zero if no value should be retrieved
+ enum FetchStatus {FETCH_OK=0, FETCH_RETRYABLE, FETCH_FATAL};
+ virtual bool fetchDone(FetchStatus *code, int *http_code) = 0;
+
+ /// Reset after transfer done, for retrying for exemple.
+ virtual bool reset() = 0;
+
+ u_int64_t datacount() {
+ return fetch_data_count;
+ }
+
+ // Callbacks
+
+ // A function to create the first buffer (typically for prepending
+ // a wav header to a raw pcm stream. If set this is called from
+ // the first curl write callback, before processing the curl data,
+ // so this happens at a point where the client may have had a look
+ // at the headers).
+ virtual void setBuf1GenCB(std::function<bool(
+ std::string& buf, void*, int)> f) {
+ buf1cb = f;
+ }
+ // Called when the network transfer is done
+ void setEOFetchCB(std::function<void(bool ok, u_int64_t count)> f) {
+ eofcb = f;
+ }
+ // Called every time we get new data from the remote
+ void setFetchBytesCB(std::function<void(u_int64_t count)> f) {
+ fbcb = f;
+ }
+
+protected:
+ size_t databufToQ(const void *contents, size_t bcnt);
+
+ std::string _url;
+ uint64_t startoffset;
+ int timeoutsecs{0};
+ u_int64_t fetch_data_count{0};
+ BufXChange<ABuffer*> *outqueue{nullptr};
+ std::function<bool(std::string&, void *, int)> buf1cb;
+ std::function<void(u_int64_t)> fbcb;
+ std::function<void(bool, u_int64_t)> eofcb;
+};
+
+#endif /* _MEDIAFETCH_H_INCLUDED_ */