text: /*
   * Copyright (c) 2001-2002 Michael David Adams.
   * All rights reserved.
   */
  
  /* __START_OF_JASPER_LICENSE__
   * 
   * JasPer License Version 2.0
   * 
   * Copyright (c) 2001-2006 Michael David Adams
   * Copyright (c) 1999-2000 Image Power, Inc.
   * Copyright (c) 1999-2000 The University of British Columbia
   * 
   * All rights reserved.
   * 
   * Permission is hereby granted, free of charge, to any person (the
   * "User") obtaining a copy of this software and associated documentation
   * files (the "Software"), to deal in the Software without restriction,
   * including without limitation the rights to use, copy, modify, merge,
   * publish, distribute, and/or sell copies of the Software, and to permit
   * persons to whom the Software is furnished to do so, subject to the
   * following conditions:
   * 
   * 1.  The above copyright notices and this permission notice (which
   * includes the disclaimer below) shall be included in all copies or
   * substantial portions of the Software.
   * 
   * 2.  The name of a copyright holder shall not be used to endorse or
   * promote products derived from the Software without specific prior
   * written permission.
   * 
   * THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS
   * LICENSE.  NO USE OF THE SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER
   * THIS DISCLAIMER.  THE SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS
   * "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
   * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
   * PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.  IN NO
   * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL
   * 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.  NO ASSURANCES ARE
   * PROVIDED BY THE COPYRIGHT HOLDERS THAT THE SOFTWARE DOES NOT INFRINGE
   * THE PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS OF ANY OTHER ENTITY.
   * EACH COPYRIGHT HOLDER DISCLAIMS ANY LIABILITY TO THE USER FOR CLAIMS
   * BROUGHT BY ANY OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL
   * PROPERTY RIGHTS OR OTHERWISE.  AS A CONDITION TO EXERCISING THE RIGHTS
   * GRANTED HEREUNDER, EACH USER HEREBY ASSUMES SOLE RESPONSIBILITY TO SECURE
   * ANY OTHER INTELLECTUAL PROPERTY RIGHTS NEEDED, IF ANY.  THE SOFTWARE
   * IS NOT FAULT-TOLERANT AND IS NOT INTENDED FOR USE IN MISSION-CRITICAL
   * SYSTEMS, SUCH AS THOSE USED IN THE OPERATION OF NUCLEAR FACILITIES,
   * AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL
   * SYSTEMS, DIRECT LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH
   * THE FAILURE OF THE SOFTWARE OR SYSTEM COULD LEAD DIRECTLY TO DEATH,
   * PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH
   * RISK ACTIVITIES").  THE COPYRIGHT HOLDERS SPECIFICALLY DISCLAIM ANY
   * EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES.
   * 
   * __END_OF_JASPER_LICENSE__
   */
  
  /******************************************************************************\
  * Includes.
  \******************************************************************************/
  
  #include "mif_cod.h"
  
  #include "jasper/jas_cm.h"
  #include "jasper/jas_tvp.h"
  #include "jasper/jas_stream.h"
  #include "jasper/jas_image.h"
  #include "jasper/jas_seq.h"
  #include "jasper/jas_string.h"
  #include "jasper/jas_malloc.h"
  #include "jasper/jas_debug.h"
  
  #include <assert.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  
  /******************************************************************************\
  * Local types.
  \******************************************************************************/
  
  typedef enum {
  	MIF_END = 0,
  	MIF_CMPT
  } mif_tagid2_t;
  
  typedef enum {
  	MIF_TLX = 0,
  	MIF_TLY,
  	MIF_WIDTH,
  	MIF_HEIGHT,
  	MIF_HSAMP,
  	MIF_VSAMP,
  	MIF_PREC,
  	MIF_SGND,
  	MIF_DATA
  } mif_tagid_t;
  
  /******************************************************************************\
  * Local functions.
  \******************************************************************************/
  
  static mif_hdr_t *mif_hdr_create(int maxcmpts);
  static void mif_hdr_destroy(mif_hdr_t *hdr);
  static int mif_hdr_growcmpts(mif_hdr_t *hdr, int maxcmpts);
  static mif_hdr_t *mif_hdr_get(jas_stream_t *in);
  static int mif_process_cmpt(mif_hdr_t *hdr, char *buf);
  static int mif_hdr_put(mif_hdr_t *hdr, jas_stream_t *out);
  static int mif_hdr_addcmpt(mif_hdr_t *hdr, int cmptno, mif_cmpt_t *cmpt);
  static mif_cmpt_t *mif_cmpt_create(void);
  static void mif_cmpt_destroy(mif_cmpt_t *cmpt);
  static char *mif_getline(jas_stream_t *jas_stream, char *buf, int bufsize);
  static int mif_getc(jas_stream_t *in);
  static mif_hdr_t *mif_makehdrfromimage(jas_image_t *image);
  
  /******************************************************************************\
  * Local data.
  \******************************************************************************/
  
  static const jas_taginfo_t mif_tags2[] = {
  	{MIF_CMPT, "component"},
  	{MIF_END, "end"},
  	{-1, 0}
  };
  
  static const jas_taginfo_t mif_tags[] = {
  	{MIF_TLX, "tlx"},
  	{MIF_TLY, "tly"},
  	{MIF_WIDTH, "width"},
  	{MIF_HEIGHT, "height"},
  	{MIF_HSAMP, "sampperx"},
  	{MIF_VSAMP, "samppery"},
  	{MIF_PREC, "prec"},
  	{MIF_SGND, "sgnd"},
  	{MIF_DATA, "data"},
  	{-1, 0}
  };
  
  /******************************************************************************\
  * Code for load operation.
  \******************************************************************************/
  
  /* Load an image from a stream in the MIF format. */
  
  jas_image_t *mif_decode(jas_stream_t *in, const char *optstr)
  {
  	mif_hdr_t *hdr;
  	jas_image_t *image;
  	jas_image_t *tmpimage;
  	jas_stream_t *tmpstream;
  	int cmptno;
  	mif_cmpt_t *cmpt;
  	jas_image_cmptparm_t cmptparm;
  	jas_seq2d_t *data;
  	int_fast32_t x;
  	int_fast32_t y;
  	int bias;
  
  	/* Avoid warnings about unused parameters. */
  	(void)optstr;
  
  	hdr = 0;
  	image = 0;
  	tmpimage = 0;
  	tmpstream = 0;
  	data = 0;
  
  	if (!(hdr = mif_hdr_get(in))) {
  		goto error;
  	}
  
  	if (!(image = jas_image_create0())) {
  		goto error;
  	}
  
  	for (cmptno = 0; cmptno < hdr->numcmpts; ++cmptno) {
  		cmpt = hdr->cmpts[cmptno];
  		tmpstream = cmpt->data ? jas_stream_fopen(cmpt->data, "rb") : in;
  		if (!tmpstream) {
  			jas_eprintf("cannot open component file %s\n", cmpt->data);
  			goto error;
  		}
  		if (!(tmpimage = jas_image_decode(tmpstream, -1, "allow_trunc=1"))) {
  			goto error;
  		}
  		if (tmpstream != in) {
  			jas_stream_close(tmpstream);
  			tmpstream = 0;
  		}
  		if (!cmpt->width) {
  			cmpt->width = jas_image_cmptwidth(tmpimage, 0);
  		}
  		if (!cmpt->height) {
  			cmpt->height = jas_image_cmptwidth(tmpimage, 0);
  		}
  		if (!cmpt->prec) {
  			cmpt->prec = jas_image_cmptprec(tmpimage, 0);
  		}
  		if (cmpt->sgnd < 0) {
  			cmpt->sgnd = jas_image_cmptsgnd(tmpimage, 0);
  		}
  		cmptparm.tlx = cmpt->tlx;
  		cmptparm.tly = cmpt->tly;
  		cmptparm.hstep = cmpt->sampperx;
  		cmptparm.vstep = cmpt->samppery;
  		cmptparm.width = cmpt->width;
  		cmptparm.height = cmpt->height;
  		cmptparm.prec = cmpt->prec;
  		cmptparm.sgnd = cmpt->sgnd;
  		if (jas_image_addcmpt(image, jas_image_numcmpts(image), &cmptparm)) {
  			goto error;
  		}
  		if (!(data = jas_seq2d_create(0, 0, cmpt->width, cmpt->height))) {
  			goto error;
  		}
  		if (jas_image_readcmpt(tmpimage, 0, 0, 0, cmpt->width, cmpt->height,
  		  data)) {
  			goto error;
  		}
  		if (cmpt->sgnd) {
  			bias = 1 << (cmpt->prec - 1);
  			for (y = 0; y < cmpt->height; ++y) {
  				for (x = 0; x < cmpt->width; ++x) {
  					*jas_seq2d_getref(data, x, y) -= bias;
  				}
  			}
  		}
  		if (jas_image_writecmpt(image, jas_image_numcmpts(image) - 1, 0, 0,
  		  cmpt->width, cmpt->height, data)) {
  			goto error;
  		}
  		jas_seq2d_destroy(data);
  		data = 0;
  		jas_image_destroy(tmpimage);
  		tmpimage = 0;
  	}
  
  	mif_hdr_destroy(hdr);
  	hdr = 0;
  	return image;
  
  error:
  	if (image) {
  		jas_image_destroy(image);
  	}
  	if (hdr) {
  		mif_hdr_destroy(hdr);
  	}
  	if (tmpstream && tmpstream != in) {
  		jas_stream_close(tmpstream);
  	}
  	if (tmpimage) {
  		jas_image_destroy(tmpimage);
  	}
  	if (data) {
  		jas_seq2d_destroy(data);
  	}
  	return 0;
  }
  
  /******************************************************************************\
  * Code for save operation.
  \******************************************************************************/
  
  /* Save an image to a stream in the the MIF format. */
  
  int mif_encode(jas_image_t *image, jas_stream_t *out, const char *optstr)
  {
  	mif_hdr_t *hdr;
  	jas_image_t *tmpimage;
  	int fmt;
  	int cmptno;
  	mif_cmpt_t *cmpt;
  	jas_image_cmptparm_t cmptparm;
  	jas_seq2d_t *data;
  	int_fast32_t x;
  	int_fast32_t y;
  	int bias;
  
  	hdr = 0;
  	tmpimage = 0;
  	data = 0;
  
  	if (optstr && *optstr != '\0') {
  		jas_eprintf("warning: ignoring unsupported options\n");
  	}
  
  	if ((fmt = jas_image_strtofmt("pnm")) < 0) {
  		jas_eprintf("error: PNM support required\n");
  		goto error;
  	}
  
  	if (!(hdr = mif_makehdrfromimage(image))) {
  		goto error;
  	}
  	if (mif_hdr_put(hdr, out)) {
  		goto error;
  	}
  
  	/* Output component data. */
  	for (cmptno = 0; cmptno < hdr->numcmpts; ++cmptno) {
  		cmpt = hdr->cmpts[cmptno];
  		if (!cmpt->data) {
  			if (!(tmpimage = jas_image_create0())) {
  				goto error;
  			}	
  			cmptparm.tlx = 0;
  			cmptparm.tly = 0;
  			cmptparm.hstep = cmpt->sampperx;
  			cmptparm.vstep = cmpt->samppery;
  			cmptparm.width = cmpt->width;
  			cmptparm.height = cmpt->height;
  			cmptparm.prec = cmpt->prec;
  			cmptparm.sgnd = false;
  			if (jas_image_addcmpt(tmpimage, jas_image_numcmpts(tmpimage),
  			  &cmptparm)) {
  				goto error;
  			}
  			jas_image_setclrspc(tmpimage, JAS_CLRSPC_SGRAY);
  			jas_image_setcmpttype(tmpimage, 0,
  			  JAS_IMAGE_CT_COLOR(JAS_CLRSPC_CHANIND_GRAY_Y));
  			if (!(data = jas_seq2d_create(0, 0, cmpt->width, cmpt->height))) {
  				goto error;
  			}
  			if (jas_image_readcmpt(image, cmptno, 0, 0, cmpt->width,
  			  cmpt->height, data)) {
  				goto error;
  			}
  			if (cmpt->sgnd) {
  				bias = 1 << (cmpt->prec - 1);
  				for (y = 0; y < cmpt->height; ++y) {
  					for (x = 0; x < cmpt->width; ++x) {
  						*jas_seq2d_getref(data, x, y) += bias;
  					}
  				}
  			}
  			if (jas_image_writecmpt(tmpimage, 0, 0, 0, cmpt->width,
  			  cmpt->height, data)) {
  				goto error;
  			}
  			jas_seq2d_destroy(data);
  			data = 0;
  			if (jas_image_encode(tmpimage, out, fmt, 0)) {
  				goto error;
  			}
  			jas_image_destroy(tmpimage);
  			tmpimage = 0;
  		}
  	}
  
  	mif_hdr_destroy(hdr);
  
  	return 0;
  
  error:
  	if (hdr) {
  		mif_hdr_destroy(hdr);
  	}
  	if (tmpimage) {
  		jas_image_destroy(tmpimage);
  	}
  	if (data) {
  		jas_seq2d_destroy(data);
  	}
  	return -1;
  }
  
  /******************************************************************************\
  * Code for validate operation.
  \******************************************************************************/
  
  int mif_validate(jas_stream_t *in)
  {
  	jas_uchar buf[MIF_MAGICLEN];
  	uint_fast32_t magic;
  
  	assert(JAS_STREAM_MAXPUTBACK >= MIF_MAGICLEN);
  
  	/* Read the validation data (i.e., the data used for detecting
  	  the format). */
  	if (jas_stream_peek(in, buf, sizeof(buf)) != sizeof(buf))
  		return -1;
  
  	/* Compute the signature value. */
  	magic = (JAS_CAST(uint_fast32_t, buf[0]) << 24) |
  	  (JAS_CAST(uint_fast32_t, buf[1]) << 16) |
  	  (JAS_CAST(uint_fast32_t, buf[2]) << 8) |
  	  buf[3];
  
  	/* Ensure that the signature is correct for this format. */
  	if (magic != MIF_MAGIC) {
  		return -1;
  	}
  
  	return 0;
  }
  
  /******************************************************************************\
  * Code for MIF header class.
  \******************************************************************************/
  
  static mif_hdr_t *mif_hdr_create(int maxcmpts)
  {
  	mif_hdr_t *hdr;
  	if (!(hdr = jas_malloc(sizeof(mif_hdr_t)))) {
  		return 0;
  	}
  	hdr->numcmpts = 0;
  	hdr->maxcmpts = 0;
  	hdr->cmpts = 0;
  	if (mif_hdr_growcmpts(hdr, maxcmpts)) {
  		mif_hdr_destroy(hdr);
  		return 0;
  	}
  	return hdr;
  }
  
  static void mif_hdr_destroy(mif_hdr_t *hdr)
  {
  	int cmptno;
  	if (hdr->cmpts) {
  		for (cmptno = 0; cmptno < hdr->numcmpts; ++cmptno) {
  			mif_cmpt_destroy(hdr->cmpts[cmptno]);
  		}
  		jas_free(hdr->cmpts);
  	}
  	jas_free(hdr);
  }
  
  static int mif_hdr_growcmpts(mif_hdr_t *hdr, int maxcmpts)
  {
  	int cmptno;
  	mif_cmpt_t **newcmpts;
  	assert(maxcmpts >= hdr->numcmpts);
  	newcmpts = (!hdr->cmpts) ? jas_alloc2(maxcmpts, sizeof(mif_cmpt_t *)) :
  	  jas_realloc2(hdr->cmpts, maxcmpts, sizeof(mif_cmpt_t *));
  	if (!newcmpts) {
  		return -1;
  	}
  	hdr->maxcmpts = maxcmpts;
  	hdr->cmpts = newcmpts;
  	for (cmptno = hdr->numcmpts; cmptno < hdr->maxcmpts; ++cmptno) {
  		hdr->cmpts[cmptno] = 0;
  	}
  	return 0;
  }
  
  static mif_hdr_t *mif_hdr_get(jas_stream_t *in)
  {
  	jas_uchar magicbuf[MIF_MAGICLEN];
  	char buf[4096];
  	mif_hdr_t *hdr;
  	bool done;
  	jas_tvparser_t *tvp;
  	int id;
  
  	hdr = 0;
  	tvp = 0;
  
  	if (jas_stream_read(in, magicbuf, MIF_MAGICLEN) != MIF_MAGICLEN) {
  		goto error;
  	}
  	if (magicbuf[0] != (MIF_MAGIC >> 24) || magicbuf[1] != ((MIF_MAGIC >> 16) &
  	  0xff) || magicbuf[2] != ((MIF_MAGIC >> 8) & 0xff) || magicbuf[3] !=
  	  (MIF_MAGIC & 0xff)) {
  		jas_eprintf("error: bad signature\n");
  		goto error;
  	}
  
  	if (!(hdr = mif_hdr_create(0))) {
  		goto error;
  	}
  
  	done = false;
  	do {
  		if (!mif_getline(in, buf, sizeof(buf))) {
  			jas_eprintf("mif_getline failed\n");
  			goto error;
  		}
  		if (buf[0] == '\0') {
  			continue;
  		}
  		JAS_DBGLOG(10, ("header line: len=%d; %s\n", strlen(buf), buf));
  		if (!(tvp = jas_tvparser_create(buf))) {
  			jas_eprintf("jas_tvparser_create failed\n");
  			goto error;
  		}
  		if (jas_tvparser_next(tvp)) {
  			jas_eprintf("cannot get record type\n");
  			goto error;
  		}
  		id = jas_taginfo_nonull(jas_taginfos_lookup(mif_tags2,
  		  jas_tvparser_gettag(tvp)))->id;
  		jas_tvparser_destroy(tvp);
  		tvp = 0;
  		switch (id) {
  		case MIF_CMPT:
  			if (mif_process_cmpt(hdr, buf)) {
  				jas_eprintf("cannot get component information\n");
  				goto error;
  			}
  			break;
  		case MIF_END:
  			done = 1;
  			break;
  		default:
  			jas_eprintf("invalid header information: %s\n", buf);
  			goto error;
  			break;
  		}
  	} while (!done);
  
  	return hdr;
  
  error:
  	if (hdr) {
  		mif_hdr_destroy(hdr);
  	}
  	if (tvp) {
  		jas_tvparser_destroy(tvp);
  	}
  	return 0;
  }
  
  static int mif_process_cmpt(mif_hdr_t *hdr, char *buf)
  {
  	jas_tvparser_t *tvp;
  	mif_cmpt_t *cmpt;
  	int id;
  
  	cmpt = 0;
  	tvp = 0;
  
  	if (!(cmpt = mif_cmpt_create())) {
  		jas_eprintf("cannot create component\n");
  		goto error;
  	}
  	cmpt->tlx = 0;
  	cmpt->tly = 0;
  	cmpt->sampperx = 0;
  	cmpt->samppery = 0;
  	cmpt->width = 0;
  	cmpt->height = 0;
  	cmpt->prec = 0;
  	cmpt->sgnd = -1;
  	cmpt->data = 0;
  
  	if (!(tvp = jas_tvparser_create(buf))) {
  		jas_eprintf("cannot create parser\n");
  		goto error;
  	}
  
  	// Skip the component keyword
  	if ((id = jas_tvparser_next(tvp))) {
  		// This should never happen.
  		abort();
  	}
  
  	// Process the tag-value pairs.
  	while (!(id = jas_tvparser_next(tvp))) {
  		switch (jas_taginfo_nonull(jas_taginfos_lookup(mif_tags,
  		  jas_tvparser_gettag(tvp)))->id) {
  		case MIF_TLX:
  			cmpt->tlx = atoi(jas_tvparser_getval(tvp));
  			break;
  		case MIF_TLY:
  			cmpt->tly = atoi(jas_tvparser_getval(tvp));
  			break;
  		case MIF_WIDTH:
  			cmpt->width = atoi(jas_tvparser_getval(tvp));
  			break;
  		case MIF_HEIGHT:
  			cmpt->height = atoi(jas_tvparser_getval(tvp));
  			break;
  		case MIF_HSAMP:
  			cmpt->sampperx = atoi(jas_tvparser_getval(tvp));
  			break;
  		case MIF_VSAMP:
  			cmpt->samppery = atoi(jas_tvparser_getval(tvp));
  			break;
  		case MIF_PREC:
  			cmpt->prec = atoi(jas_tvparser_getval(tvp));
  			break;
  		case MIF_SGND:
  			cmpt->sgnd = atoi(jas_tvparser_getval(tvp));
  			break;
  		case MIF_DATA:
  			if (!(cmpt->data = jas_strdup(jas_tvparser_getval(tvp)))) {
  				goto error;
  			}
  			break;
  		default:
  			jas_eprintf("invalid component information: %s\n", buf);
  			goto error;
  			break;
  		}
  	}
  	if (!cmpt->sampperx || !cmpt->samppery) {
  		goto error;
  	}
  	if (!cmpt->width || !cmpt->height || !cmpt->prec || cmpt->sgnd < 0) {
  		goto error;
  	}
  	if (mif_hdr_addcmpt(hdr, hdr->numcmpts, cmpt)) {
  		jas_eprintf("cannot add component\n");
  		goto error;
  	}
  	jas_tvparser_destroy(tvp);
  	return 0;
  
  error:
  	if (cmpt) {
  		mif_cmpt_destroy(cmpt);
  	}
  	if (tvp) {
  		jas_tvparser_destroy(tvp);
  	}
  	return -1;
  }
  
  static int mif_hdr_put(mif_hdr_t *hdr, jas_stream_t *out)
  {
  	int cmptno;
  	mif_cmpt_t *cmpt;
  
  	/* Output signature. */
  	if (jas_stream_putc(out, (MIF_MAGIC >> 24) & 0xff) == EOF ||
  	    jas_stream_putc(out, (MIF_MAGIC >> 16) & 0xff) == EOF ||
  	    jas_stream_putc(out, (MIF_MAGIC >> 8) & 0xff) == EOF ||
  	    jas_stream_putc(out, MIF_MAGIC & 0xff) == EOF)
  		return -1;
  
  	/* Output component information. */
  	for (cmptno = 0; cmptno < hdr->numcmpts; ++cmptno) {
  		cmpt = hdr->cmpts[cmptno];
  		jas_stream_printf(out, "component tlx=%ld tly=%ld "
  		  "sampperx=%ld samppery=%ld width=%ld height=%ld prec=%d sgnd=%d",
  		  cmpt->tlx, cmpt->tly, cmpt->sampperx, cmpt->samppery, cmpt->width,
  		  cmpt->height, cmpt->prec, cmpt->sgnd);
  		if (cmpt->data) {
  			jas_stream_printf(out, " data=%s", cmpt->data);
  		}
  		jas_stream_printf(out, "\n");
  	}
  
  	/* Output end of header indicator. */
  	jas_stream_printf(out, "end\n");
  
  	return 0;
  }
  
  static int mif_hdr_addcmpt(mif_hdr_t *hdr, int cmptno, mif_cmpt_t *cmpt)
  {
  	assert(cmptno >= hdr->numcmpts);
  	(void)cmptno;
  
  	if (hdr->numcmpts >= hdr->maxcmpts) {
  		if (mif_hdr_growcmpts(hdr, hdr->numcmpts + 128)) {
  			return -1;
  		}
  	}
  	hdr->cmpts[hdr->numcmpts] = cmpt;
  	++hdr->numcmpts;
  	return 0;
  }
  
  /******************************************************************************\
  * Code for MIF component class.
  \******************************************************************************/
  
  static mif_cmpt_t *mif_cmpt_create()
  {
  	mif_cmpt_t *cmpt;
  	if (!(cmpt = jas_malloc(sizeof(mif_cmpt_t)))) {
  		return 0;
  	}
  	memset(cmpt, 0, sizeof(mif_cmpt_t));
  	return cmpt;
  }
  
  static void mif_cmpt_destroy(mif_cmpt_t *cmpt)
  {
  	if (cmpt->data) {
  		jas_free(cmpt->data);
  	}
  	jas_free(cmpt);
  }
  
  /******************************************************************************\
  * MIF parsing code.
  \******************************************************************************/
  
  static char *mif_getline(jas_stream_t *stream, char *buf, int bufsize)
  {
  	int c;
  	char *bufptr;
  	assert(bufsize > 0);
  
  	bufptr = buf;
  	while (bufsize > 1) {
  		if ((c = mif_getc(stream)) == EOF) {
  			break;
  		}
  		*bufptr++ = c;
  		--bufsize;
  		if (c == '\n') {
  			break;
  		}
  	}
  	*bufptr = '\0';
  	if (!(bufptr = strchr(buf, '\n'))) {
  		return 0;
  	}
  	*bufptr = '\0';
  	return buf;
  }
  
  static int mif_getc(jas_stream_t *in)
  {
  	int c;
  	bool done;
  
  	done = false;
  	do {
  		switch (c = jas_stream_getc(in)) {
  		case EOF:
  			done = true;
  			break;
  		case '#':
  			for (;;) {
  				if ((c = jas_stream_getc(in)) == EOF) {
  					done = true;
  					break;
  				}	
  				if (c == '\n') {
  					done = true;
  					break;
  				}
  			}
  			break;
  		case '\\':
  			if (jas_stream_peekc(in) == '\n') {
  				jas_stream_getc(in);
  			}
  			break;
  		default:
  			done = true;
  			break;
  		}
  	} while (!done);
  
  	return c;
  }
  
  /******************************************************************************\
  * Miscellaneous functions.
  \******************************************************************************/
  
  static mif_hdr_t *mif_makehdrfromimage(jas_image_t *image)
  {
  	mif_hdr_t *hdr;
  	int cmptno;
  	mif_cmpt_t *cmpt;
  
  	if (!(hdr = mif_hdr_create(jas_image_numcmpts(image)))) {
  		return 0;
  	}
  	hdr->magic = MIF_MAGIC;
  	hdr->numcmpts = jas_image_numcmpts(image);
  	for (cmptno = 0; cmptno < hdr->numcmpts; ++cmptno) {
  		if (!(hdr->cmpts[cmptno] = jas_malloc(sizeof(mif_cmpt_t)))) {
  			goto error;
  		}
  		cmpt = hdr->cmpts[cmptno];
  		cmpt->tlx = jas_image_cmpttlx(image, cmptno);
  		cmpt->tly = jas_image_cmpttly(image, cmptno);
  		cmpt->width = jas_image_cmptwidth(image, cmptno);
  		cmpt->height = jas_image_cmptheight(image, cmptno);
  		cmpt->sampperx = jas_image_cmpthstep(image, cmptno);
  		cmpt->samppery = jas_image_cmptvstep(image, cmptno);
  		cmpt->prec = jas_image_cmptprec(image, cmptno);
  		cmpt->sgnd = jas_image_cmptsgnd(image, cmptno);
  		cmpt->data = 0;
  	}
  	return hdr;
  
  error:
  	for (cmptno = 0; cmptno < hdr->numcmpts; ++cmptno) {
  		if (hdr->cmpts[cmptno]) {
  			jas_free(hdr->cmpts[cmptno]);
  		}
  	}
  	if (hdr) {
  		jas_free(hdr);
  	}
  	return 0;
  }
  