/*

 * Copyright (c) 2001-2002 Michael David Adams.

 * All rights reserved.

 */

/* __START_OF_JASPER_LICENSE__

 * 

 * JasPer Software License

 * 

 * IMAGE POWER JPEG-2000 PUBLIC LICENSE

 * ************************************

 * 

 * GRANT:

 * 

 * Permission is hereby granted, free of charge, to any person (the "User")

 * obtaining a copy of this software and associated documentation, to deal

 * in the JasPer Software without restriction, including without limitation

 * the right to use, copy, modify, merge, publish, distribute, sublicense,

 * and/or sell copies of the JasPer Software (in source and binary forms),

 * and to permit persons to whom the JasPer Software is furnished to do so,

 * provided further that the License Conditions below are met.

 * 

 * License Conditions

 * ******************

 * 

 * A.  Redistributions of source code must retain the above copyright notice,

 * and this list of conditions, and the following disclaimer.

 * 

 * B.  Redistributions in binary form must reproduce the above copyright

 * notice, and this list of conditions, and the following disclaimer in

 * the documentation and/or other materials provided with the distribution.

 * 

 * C.  Neither the name of Image Power, Inc. nor any other contributor

 * (including, but not limited to, the University of British Columbia and

 * Michael David Adams) may be used to endorse or promote products derived

 * from this software without specific prior written permission.

 * 

 * D.  User agrees that it shall not commence any action against Image Power,

 * Inc., the University of British Columbia, Michael David Adams, or any

 * other contributors (collectively "Licensors") for infringement of any

 * intellectual property rights ("IPR") held by the User in respect of any

 * technology that User owns or has a right to license or sublicense and

 * which is an element required in order to claim compliance with ISO/IEC

 * 15444-1 (i.e., JPEG-2000 Part 1).  "IPR" means all intellectual property

 * rights worldwide arising under statutory or common law, and whether

 * or not perfected, including, without limitation, all (i) patents and

 * patent applications owned or licensable by User; (ii) rights associated

 * with works of authorship including copyrights, copyright applications,

 * copyright registrations, mask work rights, mask work applications,

 * mask work registrations; (iii) rights relating to the protection of

 * trade secrets and confidential information; (iv) any right analogous

 * to those set forth in subsections (i), (ii), or (iii) and any other

 * proprietary rights relating to intangible property (other than trademark,

 * trade dress, or service mark rights); and (v) divisions, continuations,

 * renewals, reissues and extensions of the foregoing (as and to the extent

 * applicable) now existing, hereafter filed, issued or acquired.

 * 

 * E.  If User commences an infringement action against any Licensor(s) then

 * such Licensor(s) shall have the right to terminate User's license and

 * all sublicenses that have been granted hereunder by User to other parties.

 * 

 * F.  This software is for use only in hardware or software products that

 * are compliant with ISO/IEC 15444-1 (i.e., JPEG-2000 Part 1).  No license

 * or right to this Software is granted for products that do not comply

 * with ISO/IEC 15444-1.  The JPEG-2000 Part 1 standard can be purchased

 * from the ISO.

 * 

 * THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS LICENSE.

 * NO USE OF THE JASPER SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER

 * THIS DISCLAIMER.  THE JASPER SOFTWARE IS PROVIDED BY THE LICENSORS AND

 * CONTRIBUTORS UNDER THIS LICENSE ON AN ``AS-IS'' BASIS, WITHOUT WARRANTY

 * OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION,

 * WARRANTIES THAT THE JASPER SOFTWARE IS FREE OF DEFECTS, IS MERCHANTABLE,

 * IS FIT FOR A PARTICULAR PURPOSE OR IS NON-INFRINGING.  THOSE INTENDING

 * TO USE THE JASPER SOFTWARE OR MODIFICATIONS THEREOF FOR USE IN HARDWARE

 * OR SOFTWARE PRODUCTS ARE ADVISED THAT THEIR USE MAY INFRINGE EXISTING

 * PATENTS, COPYRIGHTS, TRADEMARKS, OR OTHER INTELLECTUAL PROPERTY RIGHTS.

 * THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE JASPER SOFTWARE

 * IS WITH THE USER.  SHOULD ANY PART OF THE JASPER SOFTWARE PROVE DEFECTIVE

 * IN ANY RESPECT, THE USER (AND NOT THE INITIAL DEVELOPERS, THE UNIVERSITY

 * OF BRITISH COLUMBIA, IMAGE POWER, INC., MICHAEL DAVID ADAMS, OR ANY

 * OTHER CONTRIBUTOR) SHALL ASSUME THE COST OF ANY NECESSARY SERVICING,

 * REPAIR OR CORRECTION.  UNDER NO CIRCUMSTANCES AND UNDER NO LEGAL THEORY,

 * WHETHER TORT (INCLUDING NEGLIGENCE), CONTRACT, OR OTHERWISE, SHALL THE

 * INITIAL DEVELOPER, THE UNIVERSITY OF BRITISH COLUMBIA, IMAGE POWER, INC.,

 * MICHAEL DAVID ADAMS, ANY OTHER CONTRIBUTOR, OR ANY DISTRIBUTOR OF THE

 * JASPER SOFTWARE, OR ANY SUPPLIER OF ANY OF SUCH PARTIES, BE LIABLE TO

 * THE USER OR ANY OTHER PERSON FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR

 * CONSEQUENTIAL DAMAGES OF ANY CHARACTER INCLUDING, WITHOUT LIMITATION,

 * DAMAGES FOR LOSS OF GOODWILL, WORK STOPPAGE, COMPUTER FAILURE OR

 * MALFUNCTION, OR ANY AND ALL OTHER COMMERCIAL DAMAGES OR LOSSES, EVEN IF

 * SUCH PARTY HAD BEEN INFORMED, OR OUGHT TO HAVE KNOWN, OF THE POSSIBILITY

 * OF SUCH DAMAGES.  THE JASPER SOFTWARE AND UNDERLYING TECHNOLOGY ARE NOT

 * FAULT-TOLERANT AND ARE NOT DESIGNED, MANUFACTURED OR INTENDED FOR USE OR

 * RESALE AS ON-LINE CONTROL EQUIPMENT IN HAZARDOUS ENVIRONMENTS REQUIRING

 * FAIL-SAFE PERFORMANCE, SUCH AS IN THE OPERATION OF NUCLEAR FACILITIES,

 * AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL, DIRECT

 * LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH THE FAILURE OF THE

 * JASPER SOFTWARE OR UNDERLYING TECHNOLOGY OR PRODUCT COULD LEAD DIRECTLY

 * TO DEATH, PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE

 * ("HIGH RISK ACTIVITIES").  LICENSOR SPECIFICALLY DISCLAIMS ANY EXPRESS

 * OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES.  USER WILL NOT

 * KNOWINGLY USE, DISTRIBUTE OR RESELL THE JASPER SOFTWARE OR UNDERLYING

 * TECHNOLOGY OR PRODUCTS FOR HIGH RISK ACTIVITIES AND WILL ENSURE THAT ITS

 * CUSTOMERS AND END-USERS OF ITS PRODUCTS ARE PROVIDED WITH A COPY OF THE

 * NOTICE SPECIFIED IN THIS SECTION.

 * 

 * __END_OF_JASPER_LICENSE__

 */

/*

 * Tag-Value Parser Library

 *

 * $Id$

 */

/******************************************************************************\

* Includes.

\******************************************************************************/

#include <assert.h>

#include <stdio.h>

#include <ctype.h>

#include <stdlib.h>

#include "jasper/jas_malloc.h"

#include "jasper/jas_string.h"

#include "jasper/jas_tvp.h"

/******************************************************************************\

* Macros.

\******************************************************************************/

/* Is the specified character valid for a tag name? */

#define	JAS_TVP_ISTAG(x) \

	(isalpha(x) || (x) == '_' || isdigit(x))

/******************************************************************************\

* Code for creating and destroying a tag-value parser.

\******************************************************************************/

jas_tvparser_t *jas_tvparser_create(const char *s)

{

	jas_tvparser_t *tvp;

	if (!(tvp = jas_malloc(sizeof(jas_tvparser_t)))) {

		return 0;

	}

	if (!(tvp->buf = jas_strdup(s))) {

		jas_tvparser_destroy(tvp);

		return 0;

	}

	tvp->pos = tvp->buf;

	tvp->tag = 0;

	tvp->val = 0;

	return tvp;

}

void jas_tvparser_destroy(jas_tvparser_t *tvp)

{

	if (tvp->buf) {

		jas_free(tvp->buf);

	}

	jas_free(tvp);

}

/******************************************************************************\

* Main parsing code.

\******************************************************************************/

/* Get the next tag-value pair. */

int jas_tvparser_next(jas_tvparser_t *tvp)

{

	char *p;

	char *tag;

	const char *val;

	/* Skip any leading whitespace. */

	p = tvp->pos;

	while (*p != '\0' && isspace(*p)) {

		++p;

	}

	/* Has the end of the input data been reached? */

	if (*p == '\0') {

		/* No more tags are present. */

		tvp->pos = p;

		return 1;

	}

	/* Does the tag name begin with a valid character? */

	if (!JAS_TVP_ISTAG(*p)) {

		return -1;

	}

	/* Remember where the tag name begins. */

	tag = p;

	/* Find the end of the tag name. */

	while (*p != '\0' && JAS_TVP_ISTAG(*p)) {

		++p;

	}

	/* Has the end of the input data been reached? */

	if (*p == '\0') {

		/* The value field is empty. */

		tvp->tag = tag;

		tvp->val = "";

		tvp->pos = p;

		return 0;

	}

	/* Is a value field not present? */

	if (*p != '=') {

		if (*p != '\0' && !isspace(*p)) {

			return -1;

		}

		*p++ = '\0';

		tvp->tag = tag;

		tvp->val = "";

		tvp->pos = p;

		return 0;

	}

	*p++ = '\0';

	val = p;

	while (*p != '\0' && !isspace(*p)) {

		++p;

	}

	if (*p != '\0') {

		*p++ = '\0';

	}

	tvp->pos = p;

	tvp->tag = tag;

	tvp->val = val;

	return 0;

}

/******************************************************************************\

* Code for querying the current tag/value.

\******************************************************************************/

/* Get the current tag. */

char *jas_tvparser_gettag(jas_tvparser_t *tvp)

{

	return tvp->tag;

}

/* Get the current value. */

const char *jas_tvparser_getval(jas_tvparser_t *tvp)

{

	return tvp->val;

}

/******************************************************************************\

* Miscellaneous code.

\******************************************************************************/

/* Lookup a tag by name. */

jas_taginfo_t *jas_taginfos_lookup(jas_taginfo_t *taginfos, const char *name)

{

	jas_taginfo_t *taginfo;

	taginfo = taginfos;

	while (taginfo->id >= 0) {

		if (!strcmp(taginfo->name, name)) {

			return taginfo;

		}

		++taginfo;

	}

	return 0;

}

/* This function is simply for convenience. */

/* One can avoid testing for the special case of a null pointer, by

  using this function.   This function never returns a null pointer.  */

jas_taginfo_t *jas_taginfo_nonull(jas_taginfo_t *taginfo)

{

	static jas_taginfo_t invalidtaginfo = {

		-1, 0

	};

	return taginfo ? taginfo : &invalidtaginfo;

}