ccache_util.c

harvest是一个下载html网页得机器人

static char rcsid[] = "ccache_util.c,v 1.15 1995/11/29 00:48:33 duane Exp";
/*
 * ccache_util.c - common util functions for daemon and client stub
 *
 *      MyRead()
 *      AddURL()
 *      GetURL()
 *      GetParam()
 *      AddParam()
 *      SocketWrite()
 *
 *  David Merkel & Mark Peterson, University of Colorado - Boulder, July 1994  
 *
 *  ----------------------------------------------------------------------
 *  Copyright (c) 1994, 1995.  All rights reserved.
 *  
 *    The Harvest software was developed by the Internet Research Task
 *    Force Research Group on Resource Discovery (IRTF-RD):
 *  
 *          Mic Bowman of Transarc Corporation.
 *          Peter Danzig of the University of Southern California.
 *          Darren R. Hardy of the University of Colorado at Boulder.
 *          Udi Manber of the University of Arizona.
 *          Michael F. Schwartz of the University of Colorado at Boulder.
 *          Duane Wessels of the University of Colorado at Boulder.
 *  
 *    This copyright notice applies to software in the Harvest
 *    ``src/'' directory only.  Users should consult the individual
 *    copyright notices in the ``components/'' subdirectories for
 *    copyright information about other software bundled with the
 *    Harvest source code distribution.
 *  
 *  TERMS OF USE
 *    
 *    The Harvest software may be used and re-distributed without
 *    charge, provided that the software origin and research team are
 *    cited in any use of the system.  Most commonly this is
 *    accomplished by including a link to the Harvest Home Page
 *    (http://harvest.cs.colorado.edu/) from the query page of any
 *    Broker you deploy, as well as in the query result pages.  These
 *    links are generated automatically by the standard Broker
 *    software distribution.
 *    
 *    The Harvest software is provided ``as is'', without express or
 *    implied warranty, and with no support nor obligation to assist
 *    in its use, correction, modification or enhancement.  We assume
 *    no liability with respect to the infringement of copyrights,
 *    trade secrets, or any patents, and are not responsible for
 *    consequential damages.  Proper use of the Harvest software is
 *    entirely the responsibility of the user.
 *  
 *  DERIVATIVE WORKS
 *  
 *    Users may make derivative works from the Harvest software, subject 
 *    to the following constraints:
 *  
 *      - You must include the above copyright notice and these 
 *        accompanying paragraphs in all forms of derivative works, 
 *        and any documentation and other materials related to such 
 *        distribution and use acknowledge that the software was 
 *        developed at the above institutions.
 *  
 *      - You must notify IRTF-RD regarding your distribution of 
 *        the derivative work.
 *  
 *      - You must clearly notify users that your are distributing 
 *        a modified version and not the original Harvest software.
 *  
 *      - Any derivative product is also subject to these copyright 
 *        and use restrictions.
 *  
 *    Note that the Harvest software is NOT in the public domain.  We
 *    retain copyright, as specified above.
 *  
 *  HISTORY OF FREE SOFTWARE STATUS
 *  
 *    Originally we required sites to license the software in cases
 *    where they were going to build commercial products/services
 *    around Harvest.  In June 1995 we changed this policy.  We now
 *    allow people to use the core Harvest software (the code found in
 *    the Harvest ``src/'' directory) for free.  We made this change
 *    in the interest of encouraging the widest possible deployment of
 *    the technology.  The Harvest software is really a reference
 *    implementation of a set of protocols and formats, some of which
 *    we intend to standardize.  We encourage commercial
 *    re-implementations of code complying to this set of standards.  
 *  
 */
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include "ccache.h"


/*
 * MyRead() - read that performs timeout, assumes theSocket is set
 * for nonblocking I/O 
 */
int MyRead(theSocket, message, msgLen, seconds)
     int theSocket;
     char *message;
     int msgLen;
     int seconds;
{
	fd_set readDetect;
	struct timeval timeout;
	int err, readBytes = 0, justRead = 0;

	memset(&timeout, '\0', sizeof(struct timeval));

	/* read until timeout or amount of requested bytes read */
	while (readBytes < msgLen) {
		FD_ZERO(&readDetect);
		FD_SET(theSocket, &readDetect);
		timeout.tv_sec = seconds;
		timeout.tv_usec = 0;

		/* wait for data for seconds */
		err = select(theSocket + 1, &readDetect, NULL, NULL, &timeout);
		if (err < 0) {
#if DEBUG > 3
			printf("select error\n");
#endif
			if (errno == EINTR)
				continue;
			perror("select");
			exit(1);
		}
		/* timeout on the read */
		if (err == 0) {
#if DEBUG > 3
			printf("read timeout\n");
#endif
			return (readBytes);
		}
		if (FD_ISSET(theSocket, &readDetect)) {
			justRead = read(theSocket, message, msgLen);
			if (!justRead)
				return (0);
			readBytes += justRead;
		}
	}
	return (readBytes);
}


/* 
 * AddURL() - adds URL struct to byte stream message for transmission
 */
int AddURL(theURL, theMessage, bufSize, startIndex, lastParam)
     URL *theURL;
     char **theMessage;
     int bufSize;
     int startIndex;
     Boolean lastParam;
{
	int index = 0, length = bufSize;

	index = AddParam(theURL->url, STR, theMessage, &length, startIndex, FALSE);

	index = AddParam((char *) &(theURL->type), INT, theMessage,
	    &length, index, FALSE);

	index = AddParam(theURL->pathname, STR, theMessage, &length, index, FALSE);

	index = AddParam(theURL->host, STR, theMessage, &length, index, FALSE);

	index = AddParam((char *) &(theURL->port), INT, theMessage,
	    &length, index, FALSE);

	index = AddParam(theURL->user, STR, theMessage,
	    &length, index, FALSE);

	index = AddParam(theURL->password, STR, theMessage,
	    &length, index, FALSE);

	index = AddParam((char *) &(theURL->gophertype), INT, theMessage,
	    &length, index, FALSE);

	index = AddParam(theURL->filename, STR, theMessage,
	    &length, index, FALSE);

#ifdef USE_MD5
	index = AddParam((char *) &(theURL->fp), POINTER, theMessage,
	    &length, index, FALSE);

	index = AddParam(theURL->md5, STR, theMessage,
	    &length, index, lastParam);

#endif

#ifndef USE_MD5
	index = AddParam((char *) &(theURL->fp), POINTER, theMessage,
	    &length, index, lastParam);
#endif

	return (index);
}


/*
 * GetURL() - retrieves and assembles a URL struct from a byte
 * stream
 */
int GetURL(theURL, theSocket)
     URL *theURL;
     int theSocket;
{
	if (GetParam((char **) &(theURL->url), STR, theSocket) < 0)
		return (-1);

	if (GetParam((char **) &(theURL->type), INT, theSocket) < 0)
		return (-1);

	if (GetParam((char **) &(theURL->pathname), STR, theSocket) < 0)
		return (-1);

	if (GetParam((char **) &(theURL->host), STR, theSocket) < 0)
		return (-1);

	if (GetParam((char **) &(theURL->port), INT, theSocket) < 0)
		return (-1);

	if (GetParam((char **) &(theURL->user), STR, theSocket) < 0)
		return (-1);

	if (GetParam((char **) &(theURL->password), STR, theSocket) < 0)
		return (-1);

	if (GetParam((char **) &(theURL->gophertype), INT, theSocket) < 0)
		return (-1);

	if (GetParam((char **) &(theURL->filename), STR, theSocket) < 0)
		return (-1);

	if (GetParam((char **) &(theURL->fp), POINTER, theSocket) < 0)
		return (-1);

	if (GetParam((char **) &(theURL->md5), STR, theSocket) < 0)
		return (-1);

	return (1);
}


/* 
 * GetParam() - Get one parameter from a byte stream
 * NOTE: paramBuf must be **, and NOT pre malloc'd.  this routine mallocs
 * for you
 */
int GetParam(paramBuf, paramType, theSocket)
     char **paramBuf;
     PType paramType;
     int theSocket;
{
	Boolean gotEndMark = FALSE;
	Boolean gotCR = FALSE;
	Boolean gotLF = FALSE;
	char *tempBuf, *tempPtr, cast[sizeof(int)];
	int index = 0, readLength, bufSize = INIT_PARAM_LEN;

	tempBuf = (char *) malloc(bufSize);
	if (!tempBuf)
		return (-1);

	/* read bytes until we find either '.<CR><LF>' or '!<CR><LF>'
	 */
	while (!gotLF) {
		readLength = MyRead(theSocket, &tempBuf[index], 1, PARAM_TIMEOUT);
		if (readLength <= 0) {
			free(tempBuf);
			return (-1);
		}
		if (index >= bufSize - 1) {
			bufSize = index + REALLOC_BLK;
			tempBuf = realloc(tempBuf, bufSize);
			if (!tempBuf)
				return (-1);
		}
		switch (tempBuf[index]) {
		case BLOCK_END:
		case PARAM_END:
			gotEndMark = TRUE;
			gotCR = FALSE;
			break;

		case CARRG_RET:
			if (gotEndMark) {
				gotEndMark = FALSE;
				gotCR = TRUE;
			} else {
				gotEndMark = FALSE;
				gotCR = FALSE;
			}
			break;

		case LINE_FEED:
			if ((!gotEndMark) && (gotCR))
				gotLF = TRUE;
			else {
				gotEndMark = FALSE;
				gotCR = FALSE;
			}
			break;

		default:
			gotEndMark = FALSE;
			gotCR = FALSE;
			break;
		}
		index++;
	}

	/* based on paramType, copy data into return buffer */
	switch (paramType) {
	case STR:
	case POINTER:
	case MD5:
		*paramBuf = (char *) malloc(index - TERM_LEN);
		memcpy(*paramBuf, tempBuf, index - TERM_LEN);
		break;

	case INT:
		memcpy(cast, tempBuf, sizeof(int));
		memcpy(*paramBuf, cast, sizeof(int));
		break;

	default:
		return (-1);
	}

	free(tempBuf);
	return (index - TERM_LEN);
}


/*
 * AddParam() - Add a paramter into a buffer, use urld protocol...
 * end of parameter gets '.<CR><LF>' and last param in block
 * gets '!<CR<LF>'
 */
int AddParam(theParam, paramType, theMessage, msgLen, startIndex, lastParam)
     char *theParam;
     PType paramType;
     char **theMessage;		/* pointer to message buffer */
     int *msgLen;		/* current size of *theMessage */
     int startIndex;		/* index for insertion into buffer */
     Boolean lastParam;
{
	char *tempPtr;
	Boolean nullParam = FALSE;
	int paramSize;

	/* NULL parameters must be represented in byte stream */
	if (!theParam) {
		nullParam = TRUE;
		paramSize = 0;
	}
	/* determine size of parameter */
	else {
		switch (paramType) {
		case INT:
			paramSize = sizeof(int);
			break;
		case STR:
			/* make sure to include '\0' */
			paramSize = strlen(theParam) + 1;
			break;
		case POINTER:
			paramSize = sizeof(FILE *);
			break;
		case MD5:
			paramSize = MD5_LEN;
			break;
		}
	}

	/* realloc if buffer not big enough */
	if (paramSize + startIndex + TERM_LEN > *msgLen) {
		*theMessage = realloc(*theMessage, startIndex + paramSize + TERM_LEN);
		if (!*theMessage)
			return (-1);
	}
	/* null params get double separators to indicate nothing between
	 * separators
	 */
	if (!nullParam)
		memcpy(&((*theMessage)[startIndex]), theParam, paramSize);
	else
		(*theMessage)[startIndex] = PARAM_END;

	if (lastParam)
		(*theMessage)[startIndex + paramSize] = BLOCK_END;
	else
		(*theMessage)[startIndex + paramSize] = PARAM_END;

	(*theMessage)[startIndex + paramSize + 1] = CARRG_RET;
	(*theMessage)[startIndex + paramSize + 2] = LINE_FEED;

#if DEBUG > 5
	if (lastParam) {
		FILE *theFile = fopen("./cutil_test.log", "w");
		int dbugIndex = 0;
		while (dbugIndex < startIndex + paramSize + 3) {
			(void) fputc((*theMessage)[dbugIndex], theFile);
			dbugIndex++;
		}
		(void) fputc(CARRG_RET, theFile);
		(void) fclose(theFile);
	}
#endif

	return (startIndex + paramSize + TERM_LEN);
}


/******************************************************************************
** function name: SocketWrite()
**
** preconditions: theSocket is a valid socket, and outBuf is a preallocated
**      char * holding data to be written to theSocket.
**
** postconditions: The data in outBuf has been written to theSocket, and the
**      total number of bytes written to theSocket has been returned to the
**      caller.
**
** author/credits: Code written by W. Richard Stevens,
**      from UNIX Network Programming, c1990, Prentice Hall, pp. 279-280
**
******************************************************************************/

int SocketWrite(theSocket, outBuf, numOfBytes)
     int theSocket;		/* socket to write to */
     char *outBuf;		/* the data to write to the socket */
     int numOfBytes;		/* number of bytes inside of outBuf */
{
	int bytesLeft, bytesWritten, i = 0;

	bytesLeft = numOfBytes;
	while (bytesLeft > 0) {
		bytesWritten = write(theSocket, &outBuf[i], bytesLeft);
		if (bytesWritten <= 0)
			return (bytesWritten);

		bytesLeft -= bytesWritten;
		i += bytesWritten;
	}
	return (numOfBytes - bytesLeft);
}


void PrintURL(theURL)
     URL *theURL;
{
	printf("url: %s\n", theURL->url);
	printf("type: %d\n", theURL->type);
	printf("pathname: %s\n", theURL->pathname);
	printf("host: %s\n", theURL->host);
	printf("port: %d\n", theURL->port);
	printf("user: %s\n", theURL->user);
	printf("password: %s\n", theURL->password);
	printf("gophertype: %d\n", theURL->gophertype);
	printf("filename: %s\n", theURL->filename);
	if (theURL->fp)
		printf("valid fp\n");
	else
		printf("null fp\n");
	printf("md5: %s\n", theURL->md5);
}


/*
 * gethostinhex() takes as input either a hostname or a hostip.
 * it converts this to a long if at all possible.  If invalid
 * data is given, a -1 is returned.
 */
unsigned long gethostinhex(char *host_data)
{
	struct hostent *host_info;	/* Host entry */
	u_long IPinHex;		/* Storage for the IP as a long */

	/*
	 * If the input is a hostname which is known put
	 * the information in a struct and pull the IP
	 * from that.  If it's not, assume it's a number
	 * in dot format.  In the case that this is invalid
	 * input it returns a -1.
	 */
	if ((host_info = gethostbyname(host_data)) == NULL)
		IPinHex = htonl(inet_network((char *) host_data));
	else
		IPinHex = (*(int *) host_info->h_addr);

	return (IPinHex);
}