/*
 * Copyright (c) 1985, 1989
 *    The Regents of the University of California.  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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 * 	This product includes software developed by the University of
 * 	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS 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.
 */

/*
 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
 * 
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies, and that
 * the name of Digital Equipment Corporation not be used in advertising or
 * publicity pertaining to distribution of the document or software without
 * specific, written prior permission.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

#ifndef lint
static const char sccsid[] = "@(#)subr.c	5.24 (Berkeley) 3/2/91";
static const char rcsid[] = "$Id: subr.c,v 1.1.1.3 2001/01/31 03:59:55 zarzycki Exp $";
#endif /* not lint */

/*
 *******************************************************************************
 *
 *  subr.c --
 *
 *	Miscellaneous subroutines for the name server
 *	lookup program.
 *
 *	Copyright (c) 1985
 *	Andrew Cherenson
 *	U.C. Berkeley
 *	CS298-26  Fall 1985
 *
 *******************************************************************************
 */

#include "port_before.h"

#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>

#include <netinet/in.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>

#include <ctype.h>
#include <netdb.h>
#include <setjmp.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "port_after.h"

#include "resolv.h"
#include "res.h"

/*
 *******************************************************************************
 *
 *  IntrHandler --
 *
 *	This routine is called whenever a control-C is typed.
 *	It performs three main functions:
 *	 - closes an open socket connection,
 *	 - closes an open output file (used by LookupHost, et al.),
 *	 - jumps back to the main read-eval loop.
 *
 *	If a user types a ^C in the middle of a routine that uses a socket,
 *	the routine would not be able to close the socket. To prevent an
 *	overflow of the process's open file table, the socket and output
 *	file descriptors are closed by the interrupt handler.
 *
 *  Side effects:
 *	Open file descriptors are closed.
 *	If filePtr is valid, it is closed.
 *	Flow of control returns to the main() routine.
 *
 *******************************************************************************
 */

SIG_FN
IntrHandler()
{
    extern jmp_buf env;
#if defined(BSD) && BSD >= 199006 && !defined(RISCOS_BSD) && !defined(__osf__)
    extern FILE *yyin;		/* scanner input file */
    extern void yyrestart();	/* routine to restart scanner after interrupt */
#endif
    extern void ListHost_close(void);

    SendRequest_close();
    ListHost_close();
    if (filePtr != NULL && filePtr != stdout) {
	fclose(filePtr);
	filePtr = NULL;
    }
    printf("\n");
#if defined(BSD) && BSD >= 199006 && !defined(RISCOS_BSD) && !defined(__osf__)
    yyrestart(yyin);
#endif
    longjmp(env, 1);
}


/*
 *******************************************************************************
 *
 *  Malloc --
 *  Calloc --
 *
 *      Calls the malloc library routine with SIGINT blocked to prevent
 *	corruption of malloc's data structures. We need to do this because
 *	a control-C doesn't kill the program -- it causes a return to the
 *	main command loop.
 *
 *	NOTE: This method doesn't prevent the pointer returned by malloc
 *	from getting lost, so it is possible to get "core leaks".
 *
 *	If malloc fails, the program exits.
 *
 *  Results:
 *	(address)	- address of new buffer.
 *
 *******************************************************************************
 */

char *
Malloc(size)
    int size;
{
    char	*ptr;

#ifdef SYSV
#if defined(SVR3) || defined(SVR4)
    sighold(SIGINT);
    ptr = malloc((unsigned) size);
    sigrelse(SIGINT);
#else
    { SIG_FN (*old)();
      old = signal(SIGINT, SIG_IGN);
      ptr = malloc((unsigned) size);
      signal(SIGINT, old);
    }
#endif
#else
#ifdef POSIX_SIGNALS
    { sigset_t sset;
      sigemptyset(&sset);
      sigaddset(&sset,SIGINT);
      sigprocmask(SIG_BLOCK,&sset,NULL);
      ptr = malloc((unsigned) size);
      sigprocmask(SIG_UNBLOCK,&sset,NULL);
    }
#else
    { int saveMask;
      saveMask = sigblock(sigmask(SIGINT));
      ptr = malloc((unsigned) size);
      (void) sigsetmask(saveMask);
    }
#endif
#endif
    if (ptr == NULL) {
	fflush(stdout);
	fprintf(stderr, "*** Can't allocate memory\n");
	fflush(stderr);
	abort();
	/*NOTREACHED*/
    }
    return (ptr);
}

char *
Calloc(num, size)
    register int num, size;
{
    char *ptr = Malloc(num*size);
    memset(ptr, 0, num*size);
    return(ptr);
}


/*
 *******************************************************************************
 *
 *  PrintHostInfo --
 *
 *	Prints out the HostInfo structure for a host.
 *
 *******************************************************************************
 */

void
PrintHostInfo(file, title, hp)
	FILE	*file;
	char	*title;
	register HostInfo *hp;
{
	register char		**cp;
	register ServerInfo	**sp;
	char			comma;
	int			i;

	fprintf(file, "%-7s  %s", title, hp->name);

	if (hp->addrList != NULL) {
	    if (hp->addrList[1] != NULL) {
		fprintf(file, "\nAddresses:");
	    } else {
		fprintf(file, "\nAddress:");
	    }
	    comma = ' ';
	    i = 0;
	    for (cp = hp->addrList; cp && *cp; cp++) {
		i++;
		if (i > 4) {
		    fprintf(file, "\n\t");
		    comma = ' ';
		    i = 0;
		}
		fprintf(file,"%c %s", comma, inet_ntoa(*(struct in_addr *)*cp));
		comma = ',';
	    }
	}

	if (hp->aliases != NULL) {
	    fprintf(file, "\nAliases:");
	    comma = ' ';
	    i = 10;
	    for (cp = hp->aliases; cp && *cp && **cp; cp++) {
		i += strlen(*cp) + 2;
		if (i > 75) {
		    fprintf(file, "\n\t");
		    comma = ' ';
		    i = 10;
		}
		fprintf(file, "%c %s", comma, *cp);
		comma = ',';
	    }
	}

	if (hp->servers != NULL) {
	    fprintf(file, "\nServed by:\n");
	    for (sp = hp->servers; *sp != NULL ; sp++) {

		fprintf(file, "- %s\n\t",  (*sp)->name);

		comma = ' ';
		i = 0;
		for (cp = (*sp)->addrList; cp && *cp && **cp; cp++) {
		    i++;
		    if (i > 4) {
			fprintf(file, "\n\t");
			comma = ' ';
			i = 0;
		    }
		    fprintf(file,
			"%c %s", comma, inet_ntoa(*(struct in_addr *)*cp));
		    comma = ',';
		}
		fprintf(file, "\n\t");

		comma = ' ';
		i = 10;
		for (cp = (*sp)->domains; cp && *cp && **cp; cp++) {
		    i += strlen(*cp) + 2;
		    if (i > 75) {
			fprintf(file, "\n\t");
			comma = ' ';
			i = 10;
		    }
		    fprintf(file, "%c %s", comma, *cp);
		    comma = ',';
		}
		fprintf(file, "\n");
	    }
	}

	fprintf(file, "\n\n");
}

/*
 *******************************************************************************
 *
 *  OpenFile --
 *
 *	Parses a command string for a file name and opens
 *	the file. The file name is copued to the argument FILE. The
 * 	parameter SIZE parameter includes space for a null byte.
 *
 *  Results:
 *	file pointer	- the open was successful.
 *	NULL		- there was an error opening the file or
 *			  the input string was invalid.
 *
 *******************************************************************************
 */

FILE *
OpenFile(string, file, size)
    char *string;
    char *file;
    size_t size;
{
	char	*redirect;
	FILE	*tmpPtr;
	int	i;

	/*
	 *  Open an output file if we see '>' or >>'.
	 *  Check for overwrite (">") or concatenation (">>").
	 */

	redirect = strchr(string, '>');
	if (redirect == NULL) {
	    return(NULL);
	}

	tmpPtr = NULL;
	if (redirect[1] == '>') {
	    i = pickString(redirect + 2, file, size);
	    if (i > 0) {
	        tmpPtr = fopen(file, "a+");
	    }
	} else {
	    i = pickString(redirect + 1, file, size);
	    if (i > 0) {
		tmpPtr = fopen(file, "w");
	    }
	}

	if (tmpPtr != NULL) {
	    redirect[0] = '\0';
	}

	return(tmpPtr);
}

/*
 *******************************************************************************
 *
 *  DecodeError --
 *
 *	Converts an error code into a character string.
 *
 *******************************************************************************
 */

const struct res_sym error_syms[] = {
	{ NOERROR,	"Success" },
	{ FORMERR,	"Format error" },
	{ SERVFAIL,	"Server failed" },
	{ NXDOMAIN,	"Non-existent host/domain" },
	{ NOTIMP,	"Not implemented" },
	{ REFUSED,	"Query refused" },
#ifdef NOCHANGE
	{ NOCHANGE,	"No change" },
#endif
	{ TIME_OUT,	"Timed out" },
	{ NO_INFO,	"No information" },
	{ ERROR,	"Unspecified error" },
	{ NONAUTH,	"Non-authoritative answer" },
	{ NO_RESPONSE,	"No response from server" },
	{ 0,		NULL }
};

const char *
DecodeError(result)
    int result;
{
	const char *string;
	int success;

	string = sym_ntos(error_syms, result, &success);
	if (success)
		return string;
	return ("BAD ERROR VALUE");
}


int
StringToClass(class, dflt, errorfile)
    char *class;
    int dflt;
    FILE *errorfile;
{
	int result, success;

	result = sym_ston(__p_class_syms, class, &success);
	if (success)
		return result;

	if (errorfile)
		fprintf(errorfile, "unknown query class: %s\n", class);
	return(dflt);
}


/*
 *******************************************************************************
 *
 *  StringToType --
 *
 *	Converts a string form of a query type name to its
 *	corresponding integer value.
 *
 *******************************************************************************
 */

int
StringToType(type, dflt, errorfile)
    char *type;
    int dflt;
    FILE *errorfile;
{
	int result, success;

	result = sym_ston(__p_type_syms, type, &success);
	if (success)
		return (result);

	if (errorfile)
		fprintf(errorfile, "unknown query type: %s\n", type);
	return (dflt);
}

/*
 *******************************************************************************
 *
 *  DecodeType --
 *
 *	Converts a query type to a descriptive name.
 *	(A more verbose form of p_type.)
 *
 *
 *******************************************************************************
 */

const char *
DecodeType(type)
	int type;
{

	return (sym_ntop(__p_type_syms, type, (int *)0));
}




/*
 * Skip over leading white space in SRC and then copy the next sequence of
 * non-whitespace characters into DEST. No more than (DEST_SIZE - 1)
 * characters are copied. DEST is always null-terminated. Returns 0 if no
 * characters could be copied into DEST. Returns the number of characters
 * in SRC that were processed (i.e. the count of characters in the leading
 * white space and the first non-whitespace sequence).
 *
 * 	int i;
 * 	char *p = "  foo bar ", *q;
 * 	char buf[100];
 *
 * 	q = p + pickString(p, buf, sizeof buff);
 * 	assert (strcmp (q, " bar ") == 0) ;
 *
 */

int
pickString(const char *src, char *dest, size_t dest_size) {
	const char *start;
	const char *end ;
	size_t sublen ;

	if (dest_size == 0 || dest == NULL || src == NULL)
		return 0;
	
	for (start = src ; isspace(*start) ; start++)
		/* nada */ ;

        for (end = start ; *end != '\0' && !isspace(*end) ; end++)
		/* nada */ ;

	sublen = end - start ;
	
	if (sublen == 0 || sublen > (dest_size - 1))
		return 0;

	strncpy (dest, start, sublen);

	dest[sublen] = '\0' ;

	return (end - src);
}




/*
 * match the string FORMAT against the string SRC. Leading whitespace in
 * FORMAT will match any amount of (including no) leading whitespace in
 * SRC. Any amount of whitespace inside FORMAT matches any non-zero amount
 * of whitespace in SRC. Value returned is 0 if match didn't occur, or the
 * amount of characters in SRC that did match 
 *
 * 	int i ;
 *
 * 	i = matchString(" a    b c", "a b c") ; 
 * 	assert (i == 5) ;
 * 	i = matchString("a b c", "  a b c");  
 * 	assert (i == 0) ;    becasue no leading white space in format
 * 	i = matchString(" a b c", " a   b     c"); 
 * 	assert(i == 12);
 * 	i = matchString("aa bb ", "aa      bb      ddd sd"); 
 * 	assert(i == 16);
 */
int
matchString (const char *format, const char *src) {
	const char *f = format;
	const char *s = src;

	if (f == NULL || s == NULL)
		goto notfound;

	if (isspace(*f)) {
		while (isspace(*f))
			f++ ;
		while (isspace(*s))
			s++ ;
	}
	
	while (1) {
		if (isspace(*f)) {
			if (!isspace(*s))
				goto notfound;
			while(isspace(*s))
				s++;
			/* any amount of whitespace in the format string
			   will match any amount of space in the source
			   string. */
			while (isspace(*f))
				f++;
		} else if (*f == '\0') {
			return (s - src);
		} else if (*f != *s) {
			goto notfound;
		} else {
			s++ ;
			f++ ;
		}
	}
 notfound:
	return 0 ;
}
