+/**
+ * \file HTTPClient.cxx - simple HTTP client engine for SimHear
+ */
+
+// Written by James Turner
+//
+// Copyright (C) 2013 James Turner <zakalawe@mac.com>
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Library General Public
+// License as published by the Free Software Foundation; either
+// version 2 of the License, or (at your option) any later version.
+//
+// This library 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
+// Library 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+//
+
#include "HTTPClient.hxx"
+#include "HTTPFileRequest.hxx"
#include <sstream>
#include <cassert>
+#include <cstdlib> // rand()
#include <list>
-#include <iostream>
#include <errno.h>
+#include <map>
+#include <stdexcept>
#include <boost/foreach.hpp>
#include <boost/algorithm/string/case_conv.hpp>
-#include <zlib.h>
-
#include <simgear/io/sg_netChat.hxx>
-#include <simgear/io/lowlevel.hxx>
+#include <simgear/io/HTTPContentDecode.hxx>
#include <simgear/misc/strutils.hxx>
#include <simgear/compiler.h>
#include <simgear/debug/logstream.hxx>
#include <simgear/timing/timestamp.hxx>
+#include <simgear/structure/exception.hxx>
#if defined( HAVE_VERSION_H ) && HAVE_VERSION_H
#include "version.h"
# endif
#endif
-using std::string;
-using std::stringstream;
-using std::vector;
-
namespace simgear
{
extern const int DEFAULT_HTTP_PORT = 80;
const char* CONTENT_TYPE_URL_ENCODED = "application/x-www-form-urlencoded";
const unsigned int MAX_INFLIGHT_REQUESTS = 32;
-const int ZLIB_DECOMPRESS_BUFFER_SIZE = 32 * 1024;
-const int ZLIB_INFLATE_WINDOW_BITS = -MAX_WBITS;
-
-// see http://www.ietf.org/rfc/rfc1952.txt for these values and
-// detailed description of the logic
-const int GZIP_HEADER_ID1 = 31;
-const int GZIP_HEADER_ID2 = 139;
-const int GZIP_HEADER_METHOD_DEFLATE = 8;
-const int GZIP_HEADER_SIZE = 10;
-const int GZIP_HEADER_FEXTRA = 1 << 2;
-const int GZIP_HEADER_FNAME = 1 << 3;
-const int GZIP_HEADER_COMMENT = 1 << 4;
-const int GZIP_HEADER_CRC = 1 << 1;
+
+class Connection;
+typedef std::multimap<std::string, Connection*> ConnectionDict;
+typedef std::list<Request_ptr> RequestList;
+
+class Client::ClientPrivate
+{
+public:
+ std::string userAgent;
+ std::string proxy;
+ int proxyPort;
+ std::string proxyAuth;
+ NetChannelPoller poller;
+ unsigned int maxConnections;
+
+ RequestList pendingRequests;
+
+// connections by host (potentially more than one)
+ ConnectionDict connections;
+
+ SGTimeStamp timeTransferSample;
+ unsigned int bytesTransferred;
+ unsigned int lastTransferRate;
+ uint64_t totalBytesDownloaded;
+};
class Connection : public NetChat
{
Connection(Client* pr) :
client(pr),
state(STATE_CLOSED),
- port(DEFAULT_HTTP_PORT),
- zlibInflateBuffer(NULL),
- zlibInflateBufferSize(0),
- zlibOutputBuffer(NULL)
+ port(DEFAULT_HTTP_PORT)
{
-
}
virtual ~Connection()
{
- if (zlibInflateBuffer) {
- free(zlibInflateBuffer);
- }
-
- if (zlibOutputBuffer) {
- free(zlibOutputBuffer);
- }
+ }
+
+ virtual void handleBufferRead (NetBuffer& buffer)
+ {
+ if( !activeRequest || !activeRequest->isComplete() )
+ return NetChat::handleBufferRead(buffer);
+
+ // Request should be aborted (signaled by setting its state to complete).
+
+ // force the state to GETTING_BODY, to simplify logic in
+ // responseComplete and handleClose
+ state = STATE_GETTING_BODY;
+ responseComplete();
}
- void setServer(const string& h, short p)
+ void setServer(const std::string& h, short p)
{
host = h;
port = p;
SG_LOG(SG_IO, SG_INFO, "HTTP socket error");
activeRequest->setFailure(error, "socket error");
activeRequest = NULL;
+ _contentDecoder.reset();
}
state = STATE_SOCKET_ERROR;
virtual void handleClose()
{
NetChat::handleClose();
-
- if ((state == STATE_GETTING_BODY) && activeRequest) {
+
+ // closing of the connection from the server side when getting the body,
+ bool canCloseState = (state == STATE_GETTING_BODY);
+ if (canCloseState && activeRequest) {
// force state here, so responseComplete can avoid closing the
// socket again
state = STATE_CLOSED;
responseComplete();
} else {
+ if (activeRequest) {
+ activeRequest->setFailure(500, "server closed connection");
+ // remove the failed request from sentRequests, so it does
+ // not get restored
+ RequestList::iterator it = std::find(sentRequests.begin(),
+ sentRequests.end(), activeRequest);
+ if (it != sentRequests.end()) {
+ sentRequests.erase(it);
+ }
+ activeRequest = NULL;
+ _contentDecoder.reset();
+ }
+
state = STATE_CLOSED;
}
sentRequests.clear();
}
+ void handleTimeout()
+ {
+ NetChat::handleError(ETIMEDOUT);
+ if (activeRequest) {
+ SG_LOG(SG_IO, SG_DEBUG, "HTTP socket timeout");
+ activeRequest->setFailure(ETIMEDOUT, "socket timeout");
+ activeRequest = NULL;
+ _contentDecoder.reset();
+ }
+
+ state = STATE_SOCKET_ERROR;
+ }
+
void queueRequest(const Request_ptr& r)
{
- queuedRequests.push_back(r);
- tryStartNextRequest();
+ queuedRequests.push_back(r);
+ tryStartNextRequest();
}
void beginResponse()
{
- assert(!sentRequests.empty());
-
- activeRequest = sentRequests.front();
+ assert(!sentRequests.empty());
+ assert(state == STATE_WAITING_FOR_RESPONSE);
+
+ activeRequest = sentRequests.front();
+
activeRequest->responseStart(buffer);
state = STATE_GETTING_HEADERS;
buffer.clear();
bodyTransferSize = -1;
chunkedTransfer = false;
- contentGZip = contentDeflate = false;
+ _contentDecoder.reset();
}
void tryStartNextRequest()
{
+ while( !queuedRequests.empty()
+ && queuedRequests.front()->isComplete() )
+ queuedRequests.pop_front();
+
if (queuedRequests.empty()) {
idleTime.stamp();
return;
}
Request_ptr r = queuedRequests.front();
- requestBodyBytesToSend = r->requestBodyLength();
-
- stringstream headerData;
- string path = r->path();
+ r->requestStart();
+
+ std::stringstream headerData;
+ std::string path = r->path();
assert(!path.empty());
- string query = r->query();
- string bodyData;
+ std::string query = r->query();
+ std::string bodyData;
if (!client->proxyHost().empty()) {
path = r->scheme() + "://" + r->host() + r->path();
}
- if (r->requestBodyType() == CONTENT_TYPE_URL_ENCODED) {
+ if (r->bodyType() == CONTENT_TYPE_URL_ENCODED) {
headerData << r->method() << " " << path << " HTTP/1.1\r\n";
bodyData = query.substr(1); // URL-encode, drop the leading '?'
headerData << "Content-Type:" << CONTENT_TYPE_URL_ENCODED << "\r\n";
headerData << "Content-Length:" << bodyData.size() << "\r\n";
} else {
headerData << r->method() << " " << path << query << " HTTP/1.1\r\n";
- if (requestBodyBytesToSend >= 0) {
- headerData << "Content-Length:" << requestBodyBytesToSend << "\r\n";
- headerData << "Content-Type:" << r->requestBodyType() << "\r\n";
+ if( r->hasBodyData() )
+ {
+ headerData << "Content-Length:" << r->bodyLength() << "\r\n";
+ headerData << "Content-Type:" << r->bodyType() << "\r\n";
}
}
headerData << "Proxy-Authorization: " << client->proxyAuth() << "\r\n";
}
- BOOST_FOREACH(string h, r->requestHeaders()) {
- headerData << h << ": " << r->header(h) << "\r\n";
+ BOOST_FOREACH(const StringMap::value_type& h, r->requestHeaders()) {
+ headerData << h.first << ": " << h.second << "\r\n";
}
headerData << "\r\n"; // final CRLF to terminate the headers
bool ok = push(headerData.str().c_str());
if (!ok) {
+ SG_LOG(SG_IO, SG_WARN, "HTTPClient: over-stuffed the socket");
// we've over-stuffed the socket, give up for now, let things
// drain down before trying to start any more requests.
return;
}
-
- while (requestBodyBytesToSend > 0) {
- char buf[4096];
- int len = 4096;
- r->getBodyData(buf, len);
- if (len > 0) {
- requestBodyBytesToSend -= len;
- if (!bufferSend(buf, len)) {
- SG_LOG(SG_IO, SG_WARN, "overflow the HTTP::Connection output buffer");
- state = STATE_SOCKET_ERROR;
- return;
+
+ if( r->hasBodyData() )
+ for(size_t body_bytes_sent = 0; body_bytes_sent < r->bodyLength();)
+ {
+ char buf[4096];
+ size_t len = r->getBodyData(buf, body_bytes_sent, 4096);
+ if( len )
+ {
+ if( !bufferSend(buf, len) )
+ {
+ SG_LOG(SG_IO,
+ SG_WARN,
+ "overflow the HTTP::Connection output buffer");
+ state = STATE_SOCKET_ERROR;
+ return;
+ }
+ body_bytes_sent += len;
+ }
+ else
+ {
+ SG_LOG(SG_IO,
+ SG_WARN,
+ "HTTP asynchronous request body generation is unsupported");
+ break;
}
- } else {
- SG_LOG(SG_IO, SG_WARN, "asynchronous request body generation is unsupported");
- break;
}
- }
- //std::cout << "did send request:" << r->url() << std::endl;
- // successfully sent, remove from queue, and maybe send the next
+ // SG_LOG(SG_IO, SG_INFO, "did start request:" << r->url() <<
+ // "\n\t @ " << reinterpret_cast<void*>(r.ptr()) <<
+ // "\n\t on connection " << this);
+ // successfully sent, remove from queue, and maybe send the next
queuedRequests.pop_front();
sentRequests.push_back(r);
-
- // pipelining, let's maybe send the next request right away
+ state = STATE_WAITING_FOR_RESPONSE;
+
+ // pipelining, let's maybe send the next request right away
tryStartNextRequest();
}
virtual void collectIncomingData(const char* s, int n)
{
idleTime.stamp();
- if ((state == STATE_GETTING_BODY) || (state == STATE_GETTING_CHUNKED_BYTES)) {
- if (contentGZip || contentDeflate) {
- expandCompressedData(s, n);
- } else {
- activeRequest->processBodyBytes(s, n);
- }
- } else {
- buffer += string(s, n);
- }
- }
+ client->receivedBytes(static_cast<unsigned int>(n));
-
- void expandCompressedData(const char* s, int n)
- {
- int reqSize = n + zlib.avail_in;
- if (reqSize > zlibInflateBufferSize) {
- // reallocate
- unsigned char* newBuf = (unsigned char*) malloc(reqSize);
- memcpy(newBuf, zlib.next_in, zlib.avail_in);
- memcpy(newBuf + zlib.avail_in, s, n);
- free(zlibInflateBuffer);
- zlibInflateBuffer = newBuf;
- zlibInflateBufferSize = reqSize;
- } else {
- // important to use memmove here, since it's very likely
- // the source and destination ranges overlap
- memmove(zlibInflateBuffer, zlib.next_in, zlib.avail_in);
- memcpy(zlibInflateBuffer + zlib.avail_in, s, n);
- }
-
- zlib.next_in = (unsigned char*) zlibInflateBuffer;
- zlib.avail_in = reqSize;
- zlib.next_out = zlibOutputBuffer;
- zlib.avail_out = ZLIB_DECOMPRESS_BUFFER_SIZE;
-
- if (contentGZip) {
- // we clear this down to contentDeflate once the GZip header has been seen
- if (reqSize < GZIP_HEADER_SIZE) {
- return; // need more header bytes
- }
-
- if ((zlibInflateBuffer[0] != GZIP_HEADER_ID1) ||
- (zlibInflateBuffer[1] != GZIP_HEADER_ID2) ||
- (zlibInflateBuffer[2] != GZIP_HEADER_METHOD_DEFLATE))
- {
- return; // invalid GZip header
- }
-
- char flags = zlibInflateBuffer[3];
- int gzipHeaderSize = GZIP_HEADER_SIZE;
- if (flags & GZIP_HEADER_FEXTRA) {
- gzipHeaderSize += 2;
- if (reqSize < gzipHeaderSize) {
- return; // need more header bytes
- }
-
- unsigned short extraHeaderBytes = *(reinterpret_cast<unsigned short*>(zlibInflateBuffer + GZIP_HEADER_FEXTRA));
- if ( sgIsBigEndian() ) {
- sgEndianSwap( &extraHeaderBytes );
- }
-
- gzipHeaderSize += extraHeaderBytes;
- if (reqSize < gzipHeaderSize) {
- return; // need more header bytes
- }
- }
-
- if (flags & GZIP_HEADER_FNAME) {
- gzipHeaderSize++;
- while (gzipHeaderSize <= reqSize) {
- if (zlibInflateBuffer[gzipHeaderSize-1] == 0) {
- break; // found terminating NULL character
- }
- }
- }
-
- if (flags & GZIP_HEADER_COMMENT) {
- gzipHeaderSize++;
- while (gzipHeaderSize <= reqSize) {
- if (zlibInflateBuffer[gzipHeaderSize-1] == 0) {
- break; // found terminating NULL character
- }
- }
- }
-
- if (flags & GZIP_HEADER_CRC) {
- gzipHeaderSize += 2;
- }
-
- if (reqSize < gzipHeaderSize) {
- return; // need more header bytes
- }
-
- zlib.next_in += gzipHeaderSize;
- zlib.avail_in = reqSize - gzipHeaderSize;
- // now we've processed the GZip header, can decode as deflate
- contentGZip = false;
- contentDeflate = true;
- }
-
- int writtenSize = 0;
- do {
- int result = inflate(&zlib, Z_NO_FLUSH);
- if (result == Z_OK || result == Z_STREAM_END) {
-
- } else {
- SG_LOG(SG_IO, SG_WARN, "got Zlib error:" << result);
- return;
- }
-
- writtenSize = ZLIB_DECOMPRESS_BUFFER_SIZE - zlib.avail_out;
- } while ((writtenSize == 0) && (zlib.avail_in > 0));
-
- if (writtenSize > 0) {
- activeRequest->processBodyBytes((const char*) zlibOutputBuffer, writtenSize);
- }
+ if( (state == STATE_GETTING_BODY)
+ || (state == STATE_GETTING_CHUNKED_BYTES) )
+ _contentDecoder.receivedBytes(s, n);
+ else
+ buffer.append(s, n);
}
-
+
virtual void foundTerminator(void)
{
idleTime.stamp();
switch (state) {
- case STATE_IDLE:
+ case STATE_WAITING_FOR_RESPONSE:
beginResponse();
break;
case STATE_GETTING_CHUNKED_BYTES:
setTerminator("\r\n");
state = STATE_GETTING_CHUNKED;
+ buffer.clear();
break;
buffer.clear();
break;
+ case STATE_IDLE:
+ SG_LOG(SG_IO, SG_WARN, "HTTP got data in IDLE state, bad server?");
+
default:
break;
}
return false;
}
+ assert(sentRequests.empty());
return idleTime.elapsedMSec() > 1000 * 10; // ten seconds
}
{
return !queuedRequests.empty() && (sentRequests.size() < MAX_INFLIGHT_REQUESTS);
}
+
+ bool isActive() const
+ {
+ return !queuedRequests.empty() || !sentRequests.empty();
+ }
private:
bool connectToHost()
{
void processHeader()
{
- string h = strutils::simplify(buffer);
+ std::string h = strutils::simplify(buffer);
if (h.empty()) { // blank line terminates headers
headersComplete();
-
- if (contentGZip || contentDeflate) {
- memset(&zlib, 0, sizeof(z_stream));
- if (!zlibOutputBuffer) {
- zlibOutputBuffer = (unsigned char*) malloc(ZLIB_DECOMPRESS_BUFFER_SIZE);
- }
-
- // NULLs means we'll get default alloc+free methods
- // which is absolutely fine
- zlib.avail_out = ZLIB_DECOMPRESS_BUFFER_SIZE;
- zlib.next_out = zlibOutputBuffer;
- if (inflateInit2(&zlib, ZLIB_INFLATE_WINDOW_BITS) != Z_OK) {
- SG_LOG(SG_IO, SG_WARN, "inflateInit2 failed");
- }
- }
-
- if (chunkedTransfer) {
- state = STATE_GETTING_CHUNKED;
- } else if (noMessageBody || (bodyTransferSize == 0)) {
- // force the state to GETTING_BODY, to simplify logic in
- // responseComplete and handleClose
- state = STATE_GETTING_BODY;
- responseComplete();
- } else {
- setByteCount(bodyTransferSize); // may be -1, that's fine
- state = STATE_GETTING_BODY;
- }
-
return;
}
return;
}
- string key = strutils::simplify(buffer.substr(0, colonPos));
- string lkey = boost::to_lower_copy(key);
- string value = strutils::strip(buffer.substr(colonPos + 1));
+ std::string key = strutils::simplify(buffer.substr(0, colonPos));
+ std::string lkey = boost::to_lower_copy(key);
+ std::string value = strutils::strip(buffer.substr(colonPos + 1));
// only consider these if getting headers (as opposed to trailers
// of a chunked transfer)
} else if (lkey == "transfer-encoding") {
processTransferEncoding(value);
} else if (lkey == "content-encoding") {
- if (value == "gzip") {
- contentGZip = true;
- } else if (value == "deflate") {
- contentDeflate = true;
- } else if (value != "identity") {
- SG_LOG(SG_IO, SG_WARN, "unsupported content encoding:" << value);
- }
+ _contentDecoder.setEncoding(value);
}
}
activeRequest->responseHeader(lkey, value);
}
- void processTransferEncoding(const string& te)
+ void processTransferEncoding(const std::string& te)
{
if (te == "chunked") {
chunkedTransfer = true;
// blank line after chunk data
return;
}
-
+
int chunkSize = 0;
int semiPos = buffer.find(';');
if (semiPos >= 0) {
void headersComplete()
{
activeRequest->responseHeadersComplete();
+ _contentDecoder.initWithRequest(activeRequest);
+
+ if (chunkedTransfer) {
+ state = STATE_GETTING_CHUNKED;
+ } else if (noMessageBody || (bodyTransferSize == 0)) {
+ // force the state to GETTING_BODY, to simplify logic in
+ // responseComplete and handleClose
+ state = STATE_GETTING_BODY;
+ responseComplete();
+ } else {
+ setByteCount(bodyTransferSize); // may be -1, that's fine
+ state = STATE_GETTING_BODY;
+ }
}
void responseComplete()
{
- //std::cout << "responseComplete:" << activeRequest->url() << std::endl;
- activeRequest->responseComplete();
- client->requestFinished(this);
-
- if (contentDeflate) {
- inflateEnd(&zlib);
- }
+ Request_ptr completedRequest = activeRequest;
+ _contentDecoder.finish();
assert(sentRequests.front() == activeRequest);
sentRequests.pop_front();
if (doClose) {
// this will bring us into handleClose() above, which updates
// state to STATE_CLOSED
- close();
+ close();
// if we have additional requests waiting, try to start them now
- tryStartNextRequest();
- }
+ tryStartNextRequest();
+ }
}
- if (state != STATE_CLOSED) {
- state = STATE_IDLE;
- }
- setTerminator("\r\n");
+ if (state != STATE_CLOSED) {
+ state = sentRequests.empty() ? STATE_IDLE : STATE_WAITING_FOR_RESPONSE;
+ }
+
+ // notify request after we change state, so this connection is idle
+ // if completion triggers other requests (which is likely)
+ // SG_LOG(SG_IO, SG_INFO, "*** responseComplete:" << activeRequest->url());
+ completedRequest->responseComplete();
+ client->requestFinished(this);
+
+ setTerminator("\r\n");
}
enum ConnectionState {
STATE_IDLE = 0,
+ STATE_WAITING_FOR_RESPONSE,
STATE_GETTING_HEADERS,
STATE_GETTING_BODY,
STATE_GETTING_CHUNKED,
Client* client;
Request_ptr activeRequest;
ConnectionState state;
- string host;
+ std::string host;
short port;
std::string buffer;
int bodyTransferSize;
SGTimeStamp idleTime;
bool chunkedTransfer;
bool noMessageBody;
- int requestBodyBytesToSend;
-
- z_stream zlib;
- unsigned char* zlibInflateBuffer;
- int zlibInflateBufferSize;
- unsigned char* zlibOutputBuffer;
- bool contentGZip, contentDeflate;
-
- std::list<Request_ptr> queuedRequests;
- std::list<Request_ptr> sentRequests;
+
+ RequestList queuedRequests;
+ RequestList sentRequests;
+
+ ContentDecoder _contentDecoder;
};
-Client::Client()
+Client::Client() :
+ d(new ClientPrivate)
{
+ d->proxyPort = 0;
+ d->maxConnections = 4;
+ d->bytesTransferred = 0;
+ d->lastTransferRate = 0;
+ d->timeTransferSample.stamp();
+ d->totalBytesDownloaded = 0;
+
setUserAgent("SimGear-" SG_STRINGIZE(SIMGEAR_VERSION));
}
+Client::~Client()
+{
+}
+
+void Client::setMaxConnections(unsigned int maxCon)
+{
+ if (maxCon < 1) {
+ throw sg_range_exception("illegal HTTP::Client::setMaxConnections value");
+ }
+
+ d->maxConnections = maxCon;
+}
+
void Client::update(int waitTimeout)
{
- NetChannel::poll(waitTimeout);
-
- ConnectionDict::iterator it = _connections.begin();
- for (; it != _connections.end(); ) {
- if (it->second->hasIdleTimeout() || it->second->hasError() ||
- it->second->hasErrorTimeout())
+ if (!d->poller.hasChannels() && (waitTimeout > 0)) {
+ SGTimeStamp::sleepForMSec(waitTimeout);
+ } else {
+ d->poller.poll(waitTimeout);
+ }
+
+ bool waitingRequests = !d->pendingRequests.empty();
+ ConnectionDict::iterator it = d->connections.begin();
+ for (; it != d->connections.end(); ) {
+ Connection* con = it->second;
+ if (con->hasIdleTimeout() ||
+ con->hasError() ||
+ con->hasErrorTimeout() ||
+ (!con->isActive() && waitingRequests))
{
+ if (con->hasErrorTimeout()) {
+ // tell the connection we're timing it out
+ con->handleTimeout();
+ }
+
// connection has been idle for a while, clean it up
- // (or has an error condition, again clean it up)
+ // (or if we have requests waiting for a different host,
+ // or an error condition
ConnectionDict::iterator del = it++;
delete del->second;
- _connections.erase(del);
+ d->connections.erase(del);
} else {
if (it->second->shouldStartNext()) {
it->second->tryStartNextRequest();
}
-
++it;
}
- } // of connecion iteration
+ } // of connection iteration
+
+ if (waitingRequests && (d->connections.size() < d->maxConnections)) {
+ RequestList waiting(d->pendingRequests);
+ d->pendingRequests.clear();
+
+ // re-submit all waiting requests in order; this takes care of
+ // finding multiple pending items targetted to the same (new)
+ // connection
+ BOOST_FOREACH(Request_ptr req, waiting) {
+ makeRequest(req);
+ }
+ }
}
void Client::makeRequest(const Request_ptr& r)
{
- string host = r->host();
+ if( r->isComplete() )
+ return;
+
+ if( r->url().find("://") == std::string::npos ) {
+ r->setFailure(EINVAL, "malformed URL");
+ return;
+ }
+
+ if( r->url().find("http://") != 0 ) {
+ r->setFailure(EINVAL, "only HTTP protocol is supported");
+ return;
+ }
+
+ std::string host = r->host();
int port = r->port();
- if (!_proxy.empty()) {
- host = _proxy;
- port = _proxyPort;
+ if (!d->proxy.empty()) {
+ host = d->proxy;
+ port = d->proxyPort;
}
- stringstream ss;
+ Connection* con = NULL;
+ std::stringstream ss;
ss << host << "-" << port;
- string connectionId = ss.str();
+ std::string connectionId = ss.str();
+ bool havePending = !d->pendingRequests.empty();
+ bool atConnectionsLimit = d->connections.size() >= d->maxConnections;
+ ConnectionDict::iterator consEnd = d->connections.end();
+
+ // assign request to an existing Connection.
+ // various options exist here, examined in order
+ ConnectionDict::iterator it = d->connections.find(connectionId);
+ if (atConnectionsLimit && (it == consEnd)) {
+ // maximum number of connections active, queue this request
+ // when a connection goes inactive, we'll start this one
+ d->pendingRequests.push_back(r);
+ return;
+ }
- if (_connections.find(connectionId) == _connections.end()) {
- Connection* con = new Connection(this);
+ // scan for an idle Connection to the same host (likely if we're
+ // retrieving multiple resources from the same host in quick succession)
+ // if we have pending requests (waiting for a free Connection), then
+ // force new requests on this id to always use the first Connection
+ // (instead of the random selection below). This ensures that when
+ // there's pressure on the number of connections to keep alive, one
+ // host can't DoS every other.
+ int count = 0;
+ for (; (it != consEnd) && (it->first == connectionId); ++it, ++count) {
+ if (havePending || !it->second->isActive()) {
+ con = it->second;
+ break;
+ }
+ }
+
+ if (!con && atConnectionsLimit) {
+ // all current connections are busy (active), and we don't
+ // have free connections to allocate, so let's assign to
+ // an existing one randomly. Ideally we'd used whichever one will
+ // complete first but we don't have that info.
+ int index = rand() % count;
+ for (it = d->connections.find(connectionId); index > 0; --index) { ; }
+ con = it->second;
+ }
+
+ // allocate a new connection object
+ if (!con) {
+ con = new Connection(this);
con->setServer(host, port);
- _connections[connectionId] = con;
+ d->poller.addChannel(con);
+ d->connections.insert(d->connections.end(),
+ ConnectionDict::value_type(connectionId, con));
}
- _connections[connectionId]->queueRequest(r);
+ con->queueRequest(r);
+}
+
+//------------------------------------------------------------------------------
+FileRequestRef Client::save( const std::string& url,
+ const std::string& filename )
+{
+ FileRequestRef req = new FileRequest(url, filename);
+ makeRequest(req);
+ return req;
+}
+
+//------------------------------------------------------------------------------
+MemoryRequestRef Client::load(const std::string& url)
+{
+ MemoryRequestRef req = new MemoryRequest(url);
+ makeRequest(req);
+ return req;
}
void Client::requestFinished(Connection* con)
}
-void Client::setUserAgent(const string& ua)
+void Client::setUserAgent(const std::string& ua)
+{
+ d->userAgent = ua;
+}
+
+const std::string& Client::userAgent() const
+{
+ return d->userAgent;
+}
+
+const std::string& Client::proxyHost() const
+{
+ return d->proxy;
+}
+
+const std::string& Client::proxyAuth() const
+{
+ return d->proxyAuth;
+}
+
+void Client::setProxy( const std::string& proxy,
+ int port,
+ const std::string& auth )
+{
+ d->proxy = proxy;
+ d->proxyPort = port;
+ d->proxyAuth = auth;
+}
+
+bool Client::hasActiveRequests() const
{
- _userAgent = ua;
+ ConnectionDict::const_iterator it = d->connections.begin();
+ for (; it != d->connections.end(); ++it) {
+ if (it->second->isActive()) return true;
+ }
+
+ return false;
+}
+
+void Client::receivedBytes(unsigned int count)
+{
+ d->bytesTransferred += count;
+ d->totalBytesDownloaded += count;
+}
+
+unsigned int Client::transferRateBytesPerSec() const
+{
+ unsigned int e = d->timeTransferSample.elapsedMSec();
+ if (e > 400) {
+ // too long a window, ignore
+ d->timeTransferSample.stamp();
+ d->bytesTransferred = 0;
+ d->lastTransferRate = 0;
+ return 0;
+ }
+
+ if (e < 100) { // avoid really narrow windows
+ return d->lastTransferRate;
+ }
+
+ unsigned int ratio = (d->bytesTransferred * 1000) / e;
+ // run a low-pass filter
+ unsigned int smoothed = ((400 - e) * d->lastTransferRate) + (e * ratio);
+ smoothed /= 400;
+
+ d->timeTransferSample.stamp();
+ d->bytesTransferred = 0;
+ d->lastTransferRate = smoothed;
+ return smoothed;
}
-void Client::setProxy(const string& proxy, int port, const string& auth)
+uint64_t Client::totalBytesDownloaded() const
{
- _proxy = proxy;
- _proxyPort = port;
- _proxyAuth = auth;
+ return d->totalBytesDownloaded;
}
} // of namespace HTTP