boinc/client/pers_file_xfer.h

128 lines
4.2 KiB
C++

// Berkeley Open Infrastructure for Network Computing
// http://boinc.berkeley.edu
// Copyright (C) 2005 University of California
//
// This is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation;
// either version 2.1 of the License, or (at your option) any later version.
//
// This software 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 Lesser General Public License for more details.
//
// To view the GNU Lesser General Public License visit
// http://www.gnu.org/copyleft/lesser.html
// or write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#ifndef _PERS_FILE_XFER_H
#define _PERS_FILE_XFER_H
#include "client_types.h"
#include "file_xfer.h"
// PERS_FILE_XFER represents a "persistent file transfer",
// i.e. a long-term effort to upload or download a file.
// This may consist of several "episodes",
// which are HTTP operations to a particular server.
//
// The FILE_INFO has a list of URLs.
// For download, the object attempts to download the file
// from any of the URLs.
// If one fails or is not available, try another,
// using an exponential backoff policy to avoid flooding servers.
//
// For upload, try to upload the file to the first URL;
// if that fails try the others.
// a PERS_FILE_XFER is created and added to pers_file_xfer_set
// 1) when read from the client state file
// in (FILE_INFO::parse(), CLIENT_STATE::parse_state_file()
// 2) when a FILE_INFO is ready to transfer
// in CLIENT_STATE::handle_pers_file_xfers()
// a PERS_FILE_XFER p is removed from pers_file_xfer_set and freed
// 1) when p->pers_xfer_done is true
// in CLIENT_STATE::handle_pers_file_xfers()
// A FILE_XFER is created and added to file_xfer_set and linked from PFX
// 1) in PERS_FILE_XFER::start_xfer()
// A FILE_XFER is erased from file_xfer_set, unlinked from PFX and freed
// 1) when the FILE_XFER is done, in
// PERS_FILE_XFER::poll()
// PERS_FILE_XFER::check_giveup()
// 2) user request, in
// PERS_FILE_XFER::abort()
// PERS_FILE_XFER::suspend()
// 3) if the FILE_XFER_SET::insert() fails
// PERS_FILE_XFER::start_xfer()
// NOTE: when this is done, pers_xfer_done is set
//
// pointers:
// PERS_FILE_XFER -> FILE_XFER
// set in PERS_FILE_XFER::start_xfer()
// zeroed (see above)
// PERS_FILE_XFER -> FILE_INFO
// set in PERS_FILE_XFER::init()
// FILE_INFO -> PERS_FILE_XFER
// set in FILE_INFO::parse(), CLIENT_STATE::handle_pers_file_xfers()
// zeroed in PERS_FILE_XFER destructor
// Default values for exponential backoff
#define PERS_RETRY_DELAY_MIN 60 // 1 minute
#define PERS_RETRY_DELAY_MAX (60*60*4) // 4 hours
#define PERS_GIVEUP (60*60*24*7*2) // 2 weeks
// give up on xfer if this time elapses since last byte xferred
class PERS_FILE_XFER {
int nretry; // # of retries so far
double first_request_time; // time of first transfer request
void do_backoff();
public:
bool is_upload;
double next_request_time; // time to next retry the file request
double time_so_far;
// Total time there's been an active FILE_XFER for this PFX
// Currently not used for anything; not meaningful for throughput
// because could include repeated transfer
double last_time;
// when the above was last updated.
// Defined only while a transfer is active
bool pers_xfer_done;
FILE_XFER* fxp; // nonzero if file xfer in progress
FILE_INFO* fip;
PERS_FILE_XFER();
~PERS_FILE_XFER();
int init(FILE_INFO*, bool is_file_upload);
bool poll();
void handle_xfer_failure();
void retry_or_backoff();
void check_giveup(const char*);
void abort();
int write(MIOFILE& fout);
int parse(MIOFILE& fin);
int start_xfer();
void suspend();
};
class PERS_FILE_XFER_SET {
FILE_XFER_SET* file_xfers;
public:
std::vector<PERS_FILE_XFER*>pers_file_xfers;
PERS_FILE_XFER_SET(FILE_XFER_SET*);
int insert(PERS_FILE_XFER*);
int remove(PERS_FILE_XFER*);
bool poll();
void suspend();
};
#endif