trunk/Search/HttpHandler.cpp

/* ============================================================================
 * Douglas Thrift's Search Engine License
 *
 * Copyright (C) 2002, Douglas Thrift. All Rights Reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * 3. The end-user documentation included with the redistribution, if any, must
 *    include the following acknowledgment:
 *
 *       "This product includes software developed by Douglas Thrift
 *       (http://computers.douglasthrift.net/searchengine/)."
 *
 *    Alternately, this acknowledgment may appear in the software itself, if
 *    and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Douglas Thrift" and "Douglas Thrift's Search Engine" must not
 *    be used to endorse or promote products derived from this software without
 *    specific prior written permission.  For written permission, please visit
 *    http://www.douglasthrift.net/contact.cgi for contact information.
 *
 * 5. Products derived from this software may not be called "Douglas Thrift's
 *    Search Engine", nor may "Douglas Thrift's Search Engine" appear in their
 *    name, without prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ============================================================================
 */
// Douglas Thrift's Search Engine HTTP Handler
//
// Douglas Thrift
//
// HttpHandler.cpp

#include "HttpHandler.h"

HttpHandler::HttpHandler()
{
        buffer = new char[BUFSIZ + 1];

#ifdef _WIN32
        if (WSAStartup(MAKEWORD(2, 0), &data) != 0)
        {
                error(program + ": WSAStartup");
                exit(1);
        }
#endif // _WIN32

        begin = 0;
        length = 0;
        chunked = false;
}

HttpHandler::~HttpHandler()
{
        delete [] buffer;

#ifdef _WIN32
        WSACleanup();
#endif // _WIN32
}

bool HttpHandler::handle(URL &url, bool head)
{
        bool answer = false;

        if ((http = socket(PF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET)
        {
                error(program + ": Socket");
                exit(1);
        }

        sockaddr_in address;
        hostent* host;

        address.sin_family = AF_INET;

        if ((host = gethostbyname(url.getAddress().c_str())) == NULL)
        {
                error(program + ": Host: " + url.getAddress(), true);
                return answer;
        }

        address.sin_addr = *((in_addr*)*host->h_addr_list);
        address.sin_port = htons(url.getPort());

        if (connect(http, (sockaddr*)&address, sizeof(sockaddr_in)) ==
                SOCKET_ERROR)
        {
                error(program + ": Connect");
                return answer;
        }

        if (head)
        {
                putline("HEAD " + url.getPath() + " HTTP/1.1");
        }
        else
        {
                putline("GET " + url.getPath() + " HTTP/1.1");
        }

        putline("Accept: text/html; text/plain");
        putline("User-Agent: " + agent(true) + ' ' + platform());

        if (url.getPort() == 80)
        {
                putline("Host: " + url.getAddress());
        }
        else
        {
                char* port = new char[1024];
                sprintf(port, "%u", url.getPort());

                putline("Host: " + url.getAddress() + ':' + port);

                delete [] port;
        }

        putline("Connection: close");
        putline();

        code response;
        string line;

        do
        {
                line = getline();

                if (line.find("HTTP/") != 0)
                {
                        return answer;
                }

                unsigned dot = line.find('.');
                unsigned space = line.find(' ');

                unsigned major = strtoul(line.substr(5, dot - 5).c_str(), 0, 0);
                unsigned minor = strtoul(line.substr(dot + 1, space - dot - 1).c_str(), 0,
                        0);

                if (major > 1 || minor < 1)
                {
                        cerr << program << ": Potentially Incompatible Server: HTTP/" << major
                                << "." << minor << "\n";

                        return answer;
                }

                response = code(strtoul(line.substr(space + 1).c_str(), 0, 0));

                if (response < ok) do line = getline(); while (line != "");
        }
        while (response < ok);

        do
        {
                line = getline();

                if (line != "")
                {
                        unsigned colon = line.find(':');

                        string field = line.substr(0, colon);
                        string value = line.substr(colon + 1);

                        while (isspace(value[0])) value.erase(0, 1);

//                      if (field = 
                }
        }
        while (line != "");

        switch (response)
        {
        case ok:
                if (debug) cerr << "response = " << response << "\n";
                answer = true;
                break;
        case choices:
        case moved:
        case found:
                if (debug) cerr << "response = " << response << "\n"
                        << "location = " << location << "\n";
                location = getLink(location, url);
                break;
        case notfound:
        case internal:
                if (debug) cerr << "response = " << response << "\n";
                break;
        default:
                if (debug) cerr << "response = " << response << "\n";
                if (response <= 299)
                {
                        answer = true;
                }
                else if (response <= 399)
                {
                        location = getLink(location, url);
                }
                break;
        }

        return answer;
}

HttpHandler& HttpHandler::getline(string& line, char endline)
{
        int end = page.find(endline, begin);
        int newline = page.find('\n', begin);

        if (newline < end || end == string::npos)
        {
                end = newline;
        }

        line = page.substr(begin, end - begin);

        if (end == string::npos)
        {
                begin = end;
        }
        else
        {
                begin = end + 1;
        }

        return *this;
}

bool HttpHandler::good()
{
        bool answer = true;

        if (begin >= page.length())
        {
                answer = false;
        }
        else if (begin == string::npos)
        {
                answer = false;
        }

        return answer;
}

void HttpHandler::clear()
{
        closesocket(http);

        type = "";
        length = 0;
        location = "";
        begin = 0;
        page = "";
        chunked = false;
}

void HttpHandler::putline(const string line)
{
        sprintf(buffer, "%s\r\n", line.c_str());
        if (send(http, buffer, strlen(buffer), 0) == SOCKET_ERROR)
        {
                error(program + ": Send");
                exit(1);
        }
}

string HttpHandler::getline()
{
        string line;
        char byte;

        do
        {
                if (recv(http, &byte, 1, 0) == SOCKET_ERROR)
                {
                        error(program + ": Recv");
                }

                if (byte != '\r' && byte != '\n')
                {
                        line += byte;
                }
        }
        while (byte != '\n');

        return line;
}

void HttpHandler::error(const string& prefix, bool host)
{
#ifdef _WIN32
        string error;

        switch (WSAGetLastError())
        {
        case WSAEACCES:
                error = "Permission denied.";
                break;
        case WSAEADDRINUSE:
                error = "Address already in use.";
                break;
        case WSAEADDRNOTAVAIL:
                error = "Cannot assign requested address.";
                break;
        case WSAEAFNOSUPPORT:
                error = "Address family not supported by protocol family.";
                break;
        case WSAEALREADY:
                error = "Operation already in progress.";
                break;
        case WSAECONNABORTED:
                error = "Software caused connection abort.";
                break;
        case WSAECONNREFUSED:
                error = "Connection refused.";
                break;
        case WSAECONNRESET:
                error = "Connection reset by peer.";
                break;
        case WSAEDESTADDRREQ:
                error = "Destination address required.";
                break;
        case WSAEFAULT:
                error = "Bad address.";
                break;
        case WSAEHOSTDOWN:
                error = "Host is down.";
                break;
        case WSAEHOSTUNREACH:
                error = "No route to host.";
                break;
        case WSAEINPROGRESS:
                error = "Operation now in progress.";
                break;
        case WSAEINTR:
                error = "Interrupted function call.";
                break;
        case WSAEINVAL:
                error = "Invalid argument.";
                break;
        case WSAEISCONN:
                error = "Socket is already connected.";
                break;
        case WSAEMFILE:
                error = "Too many open files.";
                break;
        case WSAEMSGSIZE:
                error = "Message too long.";
                break;
        case WSAENETDOWN:
                error = "Network is down.";
                break;
        case WSAENETRESET:
                error = "Network dropped connection on reset.";
                break;
        case WSAENETUNREACH:
                error = "Network is unreachable.";
                break;
        case WSAENOBUFS:
                error = "No buffer space available.";
                break;
        case WSAENOPROTOOPT:
                error = "Bad protocol option.";
                break;
        case WSAENOTCONN:
                error = "Socket is not connected.";
                break;
        case WSAENOTSOCK:
                error = "Socket operation on non-socket.";
                break;
        case WSAEOPNOTSUPP:
                error = "Operation not supported.";
                break;
        case WSAEPFNOSUPPORT:
                error = "Protocol family not supported.";
                break;
        case WSAEPROCLIM:
                error = "Too many processes.";
                break;
        case WSAEPROTONOSUPPORT:
                error = "Protocol not supported.";
                break;
        case WSAEPROTOTYPE:
                error = "Protocol wrong type for socket.";
                break;
        case WSAESHUTDOWN:
                error = "Cannot send after socket shutdown.";
                break;
        case WSAESOCKTNOSUPPORT:
                error = "Socket type not supported.";
                break;
        case WSAETIMEDOUT:
                error = "Connection timed out.";
                break;
        case WSATYPE_NOT_FOUND:
                error = "Class type not found.";
                break;
        case WSAEWOULDBLOCK:
                error = "Resource temporarily unavailable.";
                break;
        case WSAHOST_NOT_FOUND:
                error = "Host not found.";
                break;
        case WSA_INVALID_HANDLE:
                error = "Specified event object handle is invalid.";
                break;
        case WSA_INVALID_PARAMETER:
                error = "One or more parameters are invalid.";
                break;
//      case WSAINVALIDPROCTABLE:
//              error = "Invalid procedure table from service provider.";
//              break;
//      case WSAINVALIDPROVIDER:
//              error = "Invalid service provider version number.";
//              break;
        case WSA_IO_INCOMPLETE:
                error = "Overlapped I/O event object not in signaled state.";
                break;
        case WSA_IO_PENDING:
                error = "Overlapped operations will complete later.";
                break;
        case WSA_NOT_ENOUGH_MEMORY:
                error = "Insufficient memory available.";
                break;
        case WSANOTINITIALISED:
                error = "Successful WSAStartup not yet performed.";
                break;
        case WSANO_DATA:
                error = "Valid name, no data record of requested type.";
                break;
        case WSANO_RECOVERY:
                error = "This is a non-recoverable error.";
                break;
//      case WSAPROVIDERFAILEDINIT:
//              error = "Unable to initialize a service provider.";
//              break;
        case WSASYSCALLFAILURE:
                error = "System call failure.";
                break;
        case WSASYSNOTREADY:
                error = "Network subsystem is unavailable.";
                break;
        case WSATRY_AGAIN:
                error = "Non-authoritative host not found.";
                break;
        case WSAVERNOTSUPPORTED:
                error = "WINSOCK.DLL version out of range.";
                break;
        case WSAEDISCON:
                error = "Graceful shutdown in progress.";
                break;
        case WSA_OPERATION_ABORTED:
                error = "Overlapped operation aborted.";
                break;
        default:
                error = "Unknown error.";
                break;
        }

        cerr << prefix << ": " << error << "\n";
#else
        if (host)
        {
                herror(prefix.c_str());
        }
        else
        {
                perror(prefix.c_str());
        }
#endif // _WIN32
}
Revision:	18
Committed:	2002-12-09T21:40:12-08:00 (22 years, 6 months ago) by douglas
File size:	10928 byte(s)
Log Message:	Implemented more HttpHandler stuff. Added news: protocol to those ignored by getLink().
#	User	Rev	Content
1	douglas	1	/* ============================================================================
2			* Douglas Thrift's Search Engine License
3			*
4			* Copyright (C) 2002, Douglas Thrift. All Rights Reserved.
5			* Redistribution and use in source and binary forms, with or without
6			* modification, are permitted provided that the following conditions are met:
7			*
8			* 1. Redistributions of source code must retain the above copyright notice,
9			* this list of conditions and the following disclaimer.
10			*
11			* 2. Redistributions in binary form must reproduce the above copyright notice,
12			* this list of conditions and the following disclaimer in the documentation
13			* and/or other materials provided with the distribution.
14			*
15			* 3. The end-user documentation included with the redistribution, if any, must
16			* include the following acknowledgment:
17			*
18			* "This product includes software developed by Douglas Thrift
19			* (http://computers.douglasthrift.net/searchengine/)."
20			*
21			* Alternately, this acknowledgment may appear in the software itself, if
22			* and wherever such third-party acknowledgments normally appear.
23			*
24			* 4. The names "Douglas Thrift" and "Douglas Thrift's Search Engine" must not
25			* be used to endorse or promote products derived from this software without
26			* specific prior written permission. For written permission, please visit
27			* http://www.douglasthrift.net/contact.cgi for contact information.
28			*
29			* 5. Products derived from this software may not be called "Douglas Thrift's
30			* Search Engine", nor may "Douglas Thrift's Search Engine" appear in their
31			* name, without prior written permission.
32			*
33			* THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
34			* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
35			* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
36			* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
37			* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
38			* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
39			* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
40			* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
41			* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
42			* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
43			* ============================================================================
44			*/
45			// Douglas Thrift's Search Engine HTTP Handler
46			//
47			// Douglas Thrift
48			//
49			// HttpHandler.cpp
50
51			#include "HttpHandler.h"
52
53			HttpHandler::HttpHandler()
54			{
55	douglas	14	buffer = new char[BUFSIZ + 1];
56
57	douglas	13	#ifdef _WIN32
58	douglas	14	if (WSAStartup(MAKEWORD(2, 0), &data) != 0)
59	douglas	13	{
60	douglas	17	error(program + ": WSAStartup");
61	douglas	13	exit(1);
62			}
63			#endif // _WIN32
64	douglas	1
65			begin = 0;
66	douglas	18	length = 0;
67			chunked = false;
68	douglas	1	}
69
70			HttpHandler::~HttpHandler()
71			{
72	douglas	14	delete [] buffer;
73
74	douglas	13	#ifdef _WIN32
75			WSACleanup();
76			#endif // _WIN32
77	douglas	1	}
78
79	douglas	14	bool HttpHandler::handle(URL &url, bool head)
80	douglas	1	{
81			bool answer = false;
82
83	douglas	14	if ((http = socket(PF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET)
84			{
85			error(program + ": Socket");
86			exit(1);
87			}
88	douglas	1
89	douglas	14	sockaddr_in address;
90			hostent* host;
91	douglas	1
92	douglas	14	address.sin_family = AF_INET;
93	douglas	1
94	douglas	14	if ((host = gethostbyname(url.getAddress().c_str())) == NULL)
95			{
96			error(program + ": Host: " + url.getAddress(), true);
97			return answer;
98			}
99	douglas	1
100	douglas	14	address.sin_addr = ((in_addr)*host->h_addr_list);
101			address.sin_port = htons(url.getPort());
102
103			if (connect(http, (sockaddr*)&address, sizeof(sockaddr_in)) ==
104			SOCKET_ERROR)
105			{
106			error(program + ": Connect");
107			return answer;
108			}
109
110			if (head)
111			{
112			putline("HEAD " + url.getPath() + " HTTP/1.1");
113			}
114			else
115			{
116			putline("GET " + url.getPath() + " HTTP/1.1");
117			}
118
119			putline("Accept: text/html; text/plain");
120			putline("User-Agent: " + agent(true) + ' ' + platform());
121
122			if (url.getPort() == 80)
123			{
124			putline("Host: " + url.getAddress());
125			}
126			else
127			{
128			char* port = new char[1024];
129			sprintf(port, "%u", url.getPort());
130
131			putline("Host: " + url.getAddress() + ':' + port);
132
133			delete [] port;
134			}
135
136	douglas	18	putline("Connection: close");
137	douglas	14	putline();
138
139	douglas	18	code response;
140			string line;
141	douglas	17
142	douglas	18	do
143	douglas	17	{
144	douglas	18	line = getline();
145	douglas	17
146	douglas	18	if (line.find("HTTP/") != 0)
147			{
148			return answer;
149			}
150	douglas	17
151	douglas	18	unsigned dot = line.find('.');
152			unsigned space = line.find(' ');
153	douglas	17
154	douglas	18	unsigned major = strtoul(line.substr(5, dot - 5).c_str(), 0, 0);
155			unsigned minor = strtoul(line.substr(dot + 1, space - dot - 1).c_str(), 0,
156			0);
157	douglas	17
158	douglas	18	if (major > 1 \|\| minor < 1)
159			{
160			cerr << program << ": Potentially Incompatible Server: HTTP/" << major
161			<< "." << minor << "\n";
162
163			return answer;
164			}
165
166			response = code(strtoul(line.substr(space + 1).c_str(), 0, 0));
167
168			if (response < ok) do line = getline(); while (line != "");
169	douglas	17	}
170	douglas	18	while (response < ok);
171	douglas	17
172			do
173			{
174			line = getline();
175	douglas	18
176			if (line != "")
177			{
178			unsigned colon = line.find(':');
179
180			string field = line.substr(0, colon);
181			string value = line.substr(colon + 1);
182
183			while (isspace(value[0])) value.erase(0, 1);
184
185			// if (field =
186			}
187	douglas	17	}
188			while (line != "");
189
190			switch (response)
191			{
192			case ok:
193	douglas	18	if (debug) cerr << "response = " << response << "\n";
194	douglas	17	answer = true;
195			break;
196	douglas	18	case choices:
197	douglas	17	case moved:
198			case found:
199	douglas	18	if (debug) cerr << "response = " << response << "\n"
200			<< "location = " << location << "\n";
201			location = getLink(location, url);
202	douglas	17	break;
203			case notfound:
204			case internal:
205	douglas	18	if (debug) cerr << "response = " << response << "\n";
206	douglas	17	break;
207			default:
208	douglas	18	if (debug) cerr << "response = " << response << "\n";
209			if (response <= 299)
210			{
211			answer = true;
212			}
213			else if (response <= 399)
214			{
215			location = getLink(location, url);
216			}
217	douglas	17	break;
218			}
219
220	douglas	1	return answer;
221			}
222
223			HttpHandler& HttpHandler::getline(string& line, char endline)
224			{
225			int end = page.find(endline, begin);
226			int newline = page.find('\n', begin);
227
228			if (newline < end \|\| end == string::npos)
229			{
230			end = newline;
231			}
232
233			line = page.substr(begin, end - begin);
234
235			if (end == string::npos)
236			{
237			begin = end;
238			}
239			else
240			{
241			begin = end + 1;
242			}
243
244			return *this;
245			}
246
247			bool HttpHandler::good()
248			{
249			bool answer = true;
250
251			if (begin >= page.length())
252			{
253			answer = false;
254			}
255			else if (begin == string::npos)
256			{
257			answer = false;
258			}
259
260			return answer;
261			}
262
263			void HttpHandler::clear()
264			{
265	douglas	18	closesocket(http);
266
267	douglas	17	type = "";
268			length = 0;
269			location = "";
270	douglas	1	begin = 0;
271			page = "";
272	douglas	18	chunked = false;
273	douglas	1	}
274
275	douglas	14	void HttpHandler::putline(const string line)
276			{
277			sprintf(buffer, "%s\r\n", line.c_str());
278			if (send(http, buffer, strlen(buffer), 0) == SOCKET_ERROR)
279			{
280			error(program + ": Send");
281			exit(1);
282			}
283			}
284
285	douglas	17	string HttpHandler::getline()
286			{
287			string line;
288			char byte;
289
290			do
291			{
292			if (recv(http, &byte, 1, 0) == SOCKET_ERROR)
293			{
294			error(program + ": Recv");
295			}
296
297			if (byte != '\r' && byte != '\n')
298			{
299			line += byte;
300			}
301			}
302			while (byte != '\n');
303
304			return line;
305			}
306
307	douglas	18	void HttpHandler::error(const string& prefix, bool host)
308	douglas	1	{
309	douglas	13	#ifdef _WIN32
310			string error;
311	douglas	1
312	douglas	13	switch (WSAGetLastError())
313	douglas	1	{
314	douglas	13	case WSAEACCES:
315			error = "Permission denied.";
316			break;
317			case WSAEADDRINUSE:
318			error = "Address already in use.";
319			break;
320			case WSAEADDRNOTAVAIL:
321			error = "Cannot assign requested address.";
322			break;
323			case WSAEAFNOSUPPORT:
324			error = "Address family not supported by protocol family.";
325			break;
326			case WSAEALREADY:
327			error = "Operation already in progress.";
328			break;
329			case WSAECONNABORTED:
330			error = "Software caused connection abort.";
331			break;
332			case WSAECONNREFUSED:
333			error = "Connection refused.";
334			break;
335			case WSAECONNRESET:
336			error = "Connection reset by peer.";
337			break;
338			case WSAEDESTADDRREQ:
339			error = "Destination address required.";
340			break;
341			case WSAEFAULT:
342			error = "Bad address.";
343			break;
344			case WSAEHOSTDOWN:
345			error = "Host is down.";
346			break;
347			case WSAEHOSTUNREACH:
348			error = "No route to host.";
349			break;
350			case WSAEINPROGRESS:
351			error = "Operation now in progress.";
352			break;
353			case WSAEINTR:
354			error = "Interrupted function call.";
355			break;
356			case WSAEINVAL:
357			error = "Invalid argument.";
358			break;
359			case WSAEISCONN:
360			error = "Socket is already connected.";
361			break;
362			case WSAEMFILE:
363			error = "Too many open files.";
364			break;
365			case WSAEMSGSIZE:
366			error = "Message too long.";
367			break;
368			case WSAENETDOWN:
369			error = "Network is down.";
370			break;
371			case WSAENETRESET:
372			error = "Network dropped connection on reset.";
373			break;
374			case WSAENETUNREACH:
375			error = "Network is unreachable.";
376			break;
377			case WSAENOBUFS:
378			error = "No buffer space available.";
379			break;
380			case WSAENOPROTOOPT:
381			error = "Bad protocol option.";
382			break;
383			case WSAENOTCONN:
384			error = "Socket is not connected.";
385			break;
386			case WSAENOTSOCK:
387			error = "Socket operation on non-socket.";
388			break;
389			case WSAEOPNOTSUPP:
390			error = "Operation not supported.";
391			break;
392			case WSAEPFNOSUPPORT:
393			error = "Protocol family not supported.";
394			break;
395			case WSAEPROCLIM:
396			error = "Too many processes.";
397			break;
398			case WSAEPROTONOSUPPORT:
399			error = "Protocol not supported.";
400			break;
401			case WSAEPROTOTYPE:
402			error = "Protocol wrong type for socket.";
403			break;
404			case WSAESHUTDOWN:
405			error = "Cannot send after socket shutdown.";
406			break;
407			case WSAESOCKTNOSUPPORT:
408			error = "Socket type not supported.";
409			break;
410			case WSAETIMEDOUT:
411			error = "Connection timed out.";
412			break;
413			case WSATYPE_NOT_FOUND:
414			error = "Class type not found.";
415			break;
416			case WSAEWOULDBLOCK:
417			error = "Resource temporarily unavailable.";
418			break;
419			case WSAHOST_NOT_FOUND:
420			error = "Host not found.";
421			break;
422			case WSA_INVALID_HANDLE:
423			error = "Specified event object handle is invalid.";
424			break;
425			case WSA_INVALID_PARAMETER:
426			error = "One or more parameters are invalid.";
427			break;
428			// case WSAINVALIDPROCTABLE:
429			// error = "Invalid procedure table from service provider.";
430			// break;
431			// case WSAINVALIDPROVIDER:
432			// error = "Invalid service provider version number.";
433			// break;
434			case WSA_IO_INCOMPLETE:
435			error = "Overlapped I/O event object not in signaled state.";
436			break;
437			case WSA_IO_PENDING:
438			error = "Overlapped operations will complete later.";
439			break;
440			case WSA_NOT_ENOUGH_MEMORY:
441			error = "Insufficient memory available.";
442			break;
443			case WSANOTINITIALISED:
444			error = "Successful WSAStartup not yet performed.";
445			break;
446			case WSANO_DATA:
447			error = "Valid name, no data record of requested type.";
448			break;
449			case WSANO_RECOVERY:
450			error = "This is a non-recoverable error.";
451			break;
452			// case WSAPROVIDERFAILEDINIT:
453			// error = "Unable to initialize a service provider.";
454			// break;
455			case WSASYSCALLFAILURE:
456			error = "System call failure.";
457			break;
458			case WSASYSNOTREADY:
459			error = "Network subsystem is unavailable.";
460			break;
461			case WSATRY_AGAIN:
462			error = "Non-authoritative host not found.";
463			break;
464			case WSAVERNOTSUPPORTED:
465			error = "WINSOCK.DLL version out of range.";
466			break;
467			case WSAEDISCON:
468			error = "Graceful shutdown in progress.";
469			break;
470			case WSA_OPERATION_ABORTED:
471			error = "Overlapped operation aborted.";
472			break;
473			default:
474			error = "Unknown error.";
475			break;
476			}
477	douglas	1
478	douglas	13	cerr << prefix << ": " << error << "\n";
479			#else
480			if (host)
481			{
482			herror(prefix.c_str());
483	douglas	1	}
484			else
485			{
486	douglas	13	perror(prefix.c_str());
487	douglas	1	}
488	douglas	13	#endif // _WIN32
489			}