Open Source Projects Europe

#ifndef _CURLFETCH_H_INCLUDED_

#define _CURLFETCH_H_INCLUDED_

#include <stddef.h>

#include <stdint.h>

#include <string>

#include <functional>

#include <memory>

#include "bufxchange.h"

#include "abuffer.h"

//

// Wrapper for a libcurl transfer. This uses the curl_easy interface

// in a separate thread, so any number of transfers may be performed

// in parallel.

//

// The transfer is aborted when the object is deleted, with proper

// cleanup (in practise, if the curl thread is currently working

// inside curl_easy_transfer, the curl fd is closed to abort any

// current waiting).

//

// The end of transfer is signalled by pushing an empty buffer on the queue

//

// All methods are supposedly thread-safe

class CurlFetch {

public:

    CurlFetch(const std::string& url);

    ~CurlFetch();

    void setTimeout(int secs);

    /// Start the transfer to the output queue.

    bool start(BufXChange<ABuffer*> *queue, uint64_t offset = 0);

    // Wait for HTTP headers. This allows, e.g. doing stuff depending

    // on content-type before proceeding with the actual data transfer

    bool waitForHeaders(int maxSecs = 0);

    // Retrieve header value (after a successful waitForHeaders).

    bool headerValue(const std::string& nm, std::string& val);

    // Check if the curl thread is done and retrieve the results if it

    // is. This does not wait, it returns false if the transfer is

    // still running.

    bool curlDone(int *curlcode, long *http_code);

    // 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).

    void setBuf1GenCB(std::function<bool(std::string& buf,void*,int)>);

    // Called after curl_easy_perform returns

    void setEOFetchCB(std::function<void(bool ok, u_int64_t count)> eofcb);

    // Called every time we get new data from curl

    void setFetchBytesCB(std::function<void(u_int64_t count)> fbcb);

    class Internal;

private:

    std::unique_ptr<Internal> m;

};

#endif /* _CURLFETCH_H_INCLUDED_ */