XEmacs 21.2.20 "Yoko".

[chise/xemacs-chise.git.1] / src / glyphs-eimage.c

/* EImage-specific Lisp objects.
   Copyright (C) 1993, 1994, 1998 Free Software Foundation, Inc.
   Copyright (C) 1995 Board of Trustees, University of Illinois.
   Copyright (C) 1995 Tinker Systems
   Copyright (C) 1995, 1996 Ben Wing
   Copyright (C) 1995 Sun Microsystems

This file is part of XEmacs.

XEmacs is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.

XEmacs is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with XEmacs; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

/* Synched up with: Not in FSF. */

/* Original author: Jamie Zawinski for 19.8
   font-truename stuff added by Jamie Zawinski for 19.10
   subwindow support added by Chuck Thompson
   additional XPM support added by Chuck Thompson
   initial X-Face support added by Stig
   rewritten/restructured by Ben Wing for 19.12/19.13
   GIF/JPEG support added by Ben Wing for 19.14
   PNG support added by Bill Perry for 19.14
   Improved GIF/JPEG support added by Bill Perry for 19.14
   Cleanup/simplification of error handling by Ben Wing for 19.14
   Pointer/icon overhaul, more restructuring by Ben Wing for 19.14
   GIF support changed to external Gifreader lib by Jareth Hein for 21.0
   Many changes for color work and optimizations by Jareth Hein for 21.0
   Switch of GIF/JPEG/PNG to new EImage intermediate code by Jareth Hein for 21.0
   TIFF code by Jareth Hein for 21.0
   Generalization for ms-windows by Andy Piper for 21.0
   TODO:
   Convert images.el to C and stick it in here?
 */

#include <config.h>
#include "lisp.h"
#include "lstream.h"
#include "console.h"
#include "device.h"
#include "faces.h"
#include "glyphs.h"
#include "objects.h"

#include "buffer.h"
#include "frame.h"
#include "opaque.h"

#include "sysfile.h"

#ifdef HAVE_PNG
#ifdef __cplusplus
extern "C" {
#endif
#include <png.h>
#ifdef __cplusplus
}
#endif
#else
#include <setjmp.h>
#endif
#ifdef FILE_CODING
#include "file-coding.h"
#endif

#ifdef HAVE_TIFF
DEFINE_IMAGE_INSTANTIATOR_FORMAT (tiff);
Lisp_Object Qtiff;
#endif

#ifdef HAVE_JPEG
DEFINE_IMAGE_INSTANTIATOR_FORMAT (jpeg);
Lisp_Object Qjpeg;
#endif

#ifdef HAVE_GIF
DEFINE_IMAGE_INSTANTIATOR_FORMAT (gif);
Lisp_Object Qgif;
#endif

#ifdef HAVE_PNG
DEFINE_IMAGE_INSTANTIATOR_FORMAT (png);
Lisp_Object Qpng;
#endif

\f
#ifdef HAVE_JPEG

/**********************************************************************
 *                             JPEG                                   *
 **********************************************************************/

#ifdef __cplusplus
extern "C" {
#endif
#include <jpeglib.h>
#include <jerror.h>
#ifdef __cplusplus
}
#endif

/*#define USE_TEMP_FILES_FOR_JPEG_IMAGES 1*/
static void
jpeg_validate (Lisp_Object instantiator)
{
  file_or_data_must_be_present (instantiator);
}

static Lisp_Object
jpeg_normalize (Lisp_Object inst, Lisp_Object console_type)
{
  return simple_image_type_normalize (inst, console_type, Qjpeg);
}

static int
jpeg_possible_dest_types (void)
{
  return IMAGE_COLOR_PIXMAP_MASK;
}

/* To survive the otherwise baffling complexity of making sure
   everything gets cleaned up in the presence of an error, we
   use an unwind_protect(). */

struct jpeg_unwind_data
{
  /* Stream that we need to close */
  FILE *instream;
  /* Object that holds state info for JPEG decoding */
  struct jpeg_decompress_struct *cinfo_ptr;
  /* EImage data */
  unsigned char *eimage;
};

static Lisp_Object
jpeg_instantiate_unwind (Lisp_Object unwind_obj)
{
  struct jpeg_unwind_data *data =
    (struct jpeg_unwind_data *) get_opaque_ptr (unwind_obj);

  free_opaque_ptr (unwind_obj);
  if (data->cinfo_ptr)
    jpeg_destroy_decompress (data->cinfo_ptr);

  if (data->instream)
    fclose (data->instream);

  if (data->eimage) xfree (data->eimage);

  return Qnil;
}

/*
 * ERROR HANDLING:
 *
 * The JPEG library's standard error handler (jerror.c) is divided into
 * several "methods" which you can override individually.  This lets you
 * adjust the behavior without duplicating a lot of code, which you might
 * have to update with each future release.
 *
 * Our example here shows how to override the "error_exit" method so that
 * control is returned to the library's caller when a fatal error occurs,
 * rather than calling exit() as the standard error_exit method does.
 *
 * We use C's setjmp/longjmp facility to return control.  This means that the
 * routine which calls the JPEG library must first execute a setjmp() call to
 * establish the return point.  We want the replacement error_exit to do a
 * longjmp().  But we need to make the setjmp buffer accessible to the
 * error_exit routine.  To do this, we make a private extension of the
 * standard JPEG error handler object.  (If we were using C++, we'd say we
 * were making a subclass of the regular error handler.)
 *
 * Here's the extended error handler struct:
 */

struct my_jpeg_error_mgr
{
  struct jpeg_error_mgr pub;    /* "public" fields */
  jmp_buf setjmp_buffer;        /* for return to caller */
};

#if defined(JPEG_LIB_VERSION) && (JPEG_LIB_VERSION >= 61)
METHODDEF(void)
#else
METHODDEF void
#endif
our_init_source (j_decompress_ptr cinfo)
{
}

#if defined(JPEG_LIB_VERSION) && (JPEG_LIB_VERSION >= 61)
METHODDEF(boolean)
#else
METHODDEF boolean
#endif
our_fill_input_buffer (j_decompress_ptr cinfo)
{
  /* Insert a fake EOI marker */
  struct jpeg_source_mgr *src = cinfo->src;
  static JOCTET buffer[2];

  buffer[0] = (JOCTET) 0xFF;
  buffer[1] = (JOCTET) JPEG_EOI;

  src->next_input_byte = buffer;
  src->bytes_in_buffer = 2;
  return TRUE;
}

#if defined(JPEG_LIB_VERSION) && (JPEG_LIB_VERSION >= 61)
METHODDEF(void)
#else
METHODDEF void
#endif
our_skip_input_data (j_decompress_ptr cinfo, long num_bytes)
{
  struct jpeg_source_mgr *src = NULL;

  src = (struct jpeg_source_mgr *) cinfo->src;

  if (!src)
    {
      return;
    } else if (num_bytes > src->bytes_in_buffer)
      {
        ERREXIT(cinfo, JERR_INPUT_EOF);
        /*NOTREACHED*/
      }

  src->bytes_in_buffer -= num_bytes;
  src->next_input_byte += num_bytes;
}

#if defined(JPEG_LIB_VERSION) && (JPEG_LIB_VERSION >= 61)
METHODDEF(void)
#else
METHODDEF void
#endif
our_term_source (j_decompress_ptr cinfo)
{
}

typedef struct
{
  struct jpeg_source_mgr pub;
} our_jpeg_source_mgr;

static void
jpeg_memory_src (j_decompress_ptr cinfo, JOCTET *data, unsigned int len)
{
  struct jpeg_source_mgr *src;

  if (cinfo->src == NULL)
    {   /* first time for this JPEG object? */
      cinfo->src = (struct jpeg_source_mgr *)
        (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
                                    sizeof(our_jpeg_source_mgr));
      src = (struct jpeg_source_mgr *) cinfo->src;
      src->next_input_byte = data;
    }
  src = (struct jpeg_source_mgr *) cinfo->src;
  src->init_source = our_init_source;
  src->fill_input_buffer = our_fill_input_buffer;
  src->skip_input_data = our_skip_input_data;
  src->resync_to_restart = jpeg_resync_to_restart; /* use default method */
  src->term_source = our_term_source;
  src->bytes_in_buffer = len;
  src->next_input_byte = data;
}

#if defined(JPEG_LIB_VERSION) && (JPEG_LIB_VERSION >= 61)
METHODDEF(void)
#else
METHODDEF void
#endif
my_jpeg_error_exit (j_common_ptr cinfo)
{
  /* cinfo->err really points to a my_error_mgr struct, so coerce pointer */
  struct my_jpeg_error_mgr *myerr = (struct my_jpeg_error_mgr *) cinfo->err;

  /* Return control to the setjmp point */
  longjmp (myerr->setjmp_buffer, 1);
}

#if defined(JPEG_LIB_VERSION) && (JPEG_LIB_VERSION >= 61)
METHODDEF(void)
#else
METHODDEF void
#endif
my_jpeg_output_message (j_common_ptr cinfo)
{
  char buffer[JMSG_LENGTH_MAX];

  /* Create the message */
  (*cinfo->err->format_message) (cinfo, buffer);
  warn_when_safe (Qjpeg, Qinfo, "%s", buffer);
}

/* The code in this routine is based on example.c from the JPEG library
   source code and from gif_instantiate() */
static void
jpeg_instantiate (Lisp_Object image_instance, Lisp_Object instantiator,
                  Lisp_Object pointer_fg, Lisp_Object pointer_bg,
                  int dest_mask, Lisp_Object domain)
{
  struct Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  /* It is OK for the unwind data to be local to this function,
     because the unwind-protect is always executed when this
     stack frame is still valid. */
  struct jpeg_unwind_data unwind;
  int speccount = specpdl_depth ();

  /* This struct contains the JPEG decompression parameters and pointers to
   * working space (which is allocated as needed by the JPEG library).
   */
  struct jpeg_decompress_struct cinfo;
  /* We use our private extension JPEG error handler.
   * Note that this struct must live as long as the main JPEG parameter
   * struct, to avoid dangling-pointer problems.
   */
  struct my_jpeg_error_mgr jerr;

  /* Step -1: First record our unwind-protect, which will clean up after
     any exit, normal or not */

  xzero (unwind);
  record_unwind_protect (jpeg_instantiate_unwind, make_opaque_ptr (&unwind));

  /* Step 1: allocate and initialize JPEG decompression object */

  /* We set up the normal JPEG error routines, then override error_exit. */
  cinfo.err = jpeg_std_error (&jerr.pub);
  jerr.pub.error_exit = my_jpeg_error_exit;
  jerr.pub.output_message = my_jpeg_output_message;

  /* Establish the setjmp return context for my_error_exit to use. */
  if (setjmp (jerr.setjmp_buffer))
    {
      /* If we get here, the JPEG code has signaled an error.
       * We need to clean up the JPEG object, close the input file, and return.
       */

      {
        Lisp_Object errstring;
        char buffer[JMSG_LENGTH_MAX];

        /* Create the message */
        (*cinfo.err->format_message) ((j_common_ptr) &cinfo, buffer);
        errstring = build_string (buffer);

        signal_image_error_2 ("JPEG decoding error",
                              errstring, instantiator);
      }
    }

  /* Now we can initialize the JPEG decompression object. */
  jpeg_create_decompress (&cinfo);
  unwind.cinfo_ptr = &cinfo;

  /* Step 2: specify data source (eg, a file) */

  {
    Lisp_Object data = find_keyword_in_vector (instantiator, Q_data);
    CONST Extbyte *bytes;
    Extcount len;

    /* #### This is a definite problem under Mule due to the amount of
       stack data it might allocate.  Need to be able to convert and
       write out to a file. */
    GET_STRING_BINARY_DATA_ALLOCA (data, bytes, len);
    jpeg_memory_src (&cinfo, (JOCTET *) bytes, len);
  }

  /* Step 3: read file parameters with jpeg_read_header() */

  jpeg_read_header (&cinfo, TRUE);
  /* We can ignore the return value from jpeg_read_header since
   *   (a) suspension is not possible with the stdio data source, and
   *   (b) we passed TRUE to reject a tables-only JPEG file as an error.
   * See libjpeg.doc for more info.
   */

  {
    int jpeg_gray = 0;          /* if we're dealing with a grayscale */
    /* Step 4: set parameters for decompression.   */

    /* Now that we're using EImages, send all data as 24bit color.
       The backend routine will take care of any necessary reductions.
       We do have to handle the grayscale case ourselves, however. */
    if (cinfo.jpeg_color_space == JCS_GRAYSCALE)
      {
        cinfo.out_color_space = JCS_GRAYSCALE;
        jpeg_gray = 1;
      }
    else
      {
        /* we're relying on the jpeg driver to do any other conversions,
           or signal an error if the conversion isn't supported. */
        cinfo.out_color_space = JCS_RGB;
      }

    /* Step 5: Start decompressor */
    jpeg_start_decompress (&cinfo);

    /* Step 6: Read in the data and put into EImage format (8bit RGB triples)*/

    unwind.eimage = (unsigned char*) xmalloc (cinfo.output_width * cinfo.output_height * 3);
    if (!unwind.eimage)
      signal_image_error("Unable to allocate enough memory for image", instantiator);

    {
      JSAMPARRAY row_buffer;    /* Output row buffer */
      JSAMPLE *jp;
      int row_stride;           /* physical row width in output buffer */
      unsigned char *op = unwind.eimage;

      /* We may need to do some setup of our own at this point before reading
       * the data.  After jpeg_start_decompress() we have the correct scaled
       * output image dimensions available
       * We need to make an output work buffer of the right size.
       */
      /* JSAMPLEs per row in output buffer. */
      row_stride = cinfo.output_width * cinfo.output_components;
      /* Make a one-row-high sample array that will go away when done
         with image */
      row_buffer = ((*cinfo.mem->alloc_sarray)
                    ((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1));

      /* Here we use the library's state variable cinfo.output_scanline as the
       * loop counter, so that we don't have to keep track ourselves.
       */
      while (cinfo.output_scanline < cinfo.output_height)
        {
          int i;

          /* jpeg_read_scanlines expects an array of pointers to scanlines.
           * Here the array is only one element long, but you could ask for
           * more than one scanline at a time if that's more convenient.
           */
          (void) jpeg_read_scanlines (&cinfo, row_buffer, 1);
          jp = row_buffer[0];
          for (i = 0; i < cinfo.output_width; i++)
            {
              int clr;
              if (jpeg_gray)
                {
                  unsigned char val;
#if (BITS_IN_JSAMPLE == 8)
                  val = (unsigned char)*jp++;
#else /* other option is 12 */
                  val = (unsigned char)(*jp++ >> 4);
#endif
                  for (clr = 0; clr < 3; clr++) /* copy the same value into RGB */
                      *op++ = val;
                }
              else
                {
                  for (clr = 0; clr < 3; clr++)
#if (BITS_IN_JSAMPLE == 8)
                    *op++ = (unsigned char)*jp++;
#else /* other option is 12 */
                    *op++ = (unsigned char)(*jp++ >> 4);
#endif
                }
            }
        }
    }
  }

  /* Step 6.5: Create the pixmap and set up the image instance */
  /* now instantiate */
  MAYBE_DEVMETH (XDEVICE (ii->device),
                 init_image_instance_from_eimage,
                 (ii, cinfo.output_width, cinfo.output_height, 1,
                  unwind.eimage, dest_mask,
                  instantiator, domain));

  /* Step 7: Finish decompression */

  jpeg_finish_decompress (&cinfo);
  /* We can ignore the return value since suspension is not possible
   * with the stdio data source.
   */

  /* And we're done! */
  /* This will clean up everything else. */
  unbind_to (speccount, Qnil);
}

#endif /* HAVE_JPEG */
\f
#ifdef HAVE_GIF
/**********************************************************************
 *                               GIF                                  *
 **********************************************************************/

#include "gifrlib.h"

static void
gif_validate (Lisp_Object instantiator)
{
  file_or_data_must_be_present (instantiator);
}

static Lisp_Object
gif_normalize (Lisp_Object inst, Lisp_Object console_type)
{
  return simple_image_type_normalize (inst, console_type, Qgif);
}

static int
gif_possible_dest_types (void)
{
  return IMAGE_COLOR_PIXMAP_MASK;
}

/* To survive the otherwise baffling complexity of making sure
   everything gets cleaned up in the presence of an error, we
   use an unwind_protect(). */

struct gif_unwind_data
{
  unsigned char *eimage;
  /* Object that holds the decoded data from a GIF file */
  GifFileType *giffile;
};

static Lisp_Object
gif_instantiate_unwind (Lisp_Object unwind_obj)
{
  struct gif_unwind_data *data =
    (struct gif_unwind_data *) get_opaque_ptr (unwind_obj);

  free_opaque_ptr (unwind_obj);
  if (data->giffile)
    {
      DGifCloseFile (data->giffile);
      GifFree(data->giffile);
    }
  if (data->eimage) xfree(data->eimage);

  return Qnil;
}

typedef struct gif_memory_storage
{
  Extbyte *bytes;               /* The data       */
  Extcount len;                 /* How big is it? */
  int index;                    /* Where are we?  */
} gif_memory_storage;

static size_t
gif_read_from_memory(GifByteType *buf, size_t size, VoidPtr data)
{
  gif_memory_storage *mem = (gif_memory_storage*)data;

  if (size > (mem->len - mem->index))
    return (size_t) -1;
  memcpy(buf, mem->bytes + mem->index, size);
  mem->index = mem->index + size;
  return size;
}

static int
gif_memory_close(VoidPtr data)
{
  return 0;
}

struct gif_error_struct
{
  CONST char *err_str;          /* return the error string */
  jmp_buf setjmp_buffer;        /* for return to caller */
};

static void
gif_error_func(CONST char *err_str, VoidPtr error_ptr)
{
  struct gif_error_struct *error_data = (struct gif_error_struct*)error_ptr;

  /* return to setjmp point */
  error_data->err_str = err_str;
  longjmp (error_data->setjmp_buffer, 1);
}

static void
gif_instantiate (Lisp_Object image_instance, Lisp_Object instantiator,
                 Lisp_Object pointer_fg, Lisp_Object pointer_bg,
                 int dest_mask, Lisp_Object domain)
{
  struct Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  /* It is OK for the unwind data to be local to this function,
     because the unwind-protect is always executed when this
     stack frame is still valid. */
  struct gif_unwind_data unwind;
  int speccount = specpdl_depth ();
  gif_memory_storage mem_struct;
  struct gif_error_struct gif_err;
  Extbyte *bytes;
  Extcount len;
  int height = 0;
  int width = 0;

  xzero (unwind);
  record_unwind_protect (gif_instantiate_unwind, make_opaque_ptr (&unwind));

  /* 1. Now decode the data. */

  {
    Lisp_Object data = find_keyword_in_vector (instantiator, Q_data);

    assert (!NILP (data));

    if (!(unwind.giffile = GifSetup()))
      signal_image_error ("Insufficent memory to instantiate GIF image", instantiator);

    /* set up error facilities */
    if (setjmp(gif_err.setjmp_buffer))
      {
        /* An error was signaled. No clean up is needed, as unwind handles that
           for us.  Just pass the error along. */
        Lisp_Object errstring;
        errstring = build_string (gif_err.err_str);
        signal_image_error_2 ("GIF decoding error", errstring, instantiator);
      }
    GifSetErrorFunc(unwind.giffile, (Gif_error_func)gif_error_func, (VoidPtr)&gif_err);

    GET_STRING_BINARY_DATA_ALLOCA (data, bytes, len);
    mem_struct.bytes = bytes;
    mem_struct.len = len;
    mem_struct.index = 0;
    GifSetReadFunc(unwind.giffile, gif_read_from_memory, (VoidPtr)&mem_struct);
    GifSetCloseFunc(unwind.giffile, gif_memory_close, (VoidPtr)&mem_struct);
    DGifInitRead(unwind.giffile);

    /* Then slurp the image into memory, decoding along the way.
       The result is the image in a simple one-byte-per-pixel
       format (#### the GIF routines only support 8-bit GIFs,
       it appears). */
    DGifSlurp (unwind.giffile);
  }

  /* 3. Now create the EImage(s) */
  {
    ColorMapObject *cmo = unwind.giffile->SColorMap;
    int i, j, row, pass, interlace, slice;
    unsigned char *eip;
    /* interlaced gifs have rows in this order:
       0, 8, 16, ..., 4, 12, 20, ..., 2, 6, 10, ..., 1, 3, 5, ...  */
    static int InterlacedOffset[] = { 0, 4, 2, 1 };
    static int InterlacedJumps[] = { 8, 8, 4, 2 };

    height = unwind.giffile->SHeight;
    width = unwind.giffile->SWidth;
    unwind.eimage = (unsigned char*) 
      xmalloc (width * height * 3 * unwind.giffile->ImageCount);
    if (!unwind.eimage)
      signal_image_error("Unable to allocate enough memory for image", instantiator);

    /* write the data in EImage format (8bit RGB triples) */

    for (slice = 0; slice < unwind.giffile->ImageCount; slice++)
      {
        /* We check here that that the current image covers the full "screen" size. */
        if (unwind.giffile->SavedImages[slice].ImageDesc.Height != height
            || unwind.giffile->SavedImages[slice].ImageDesc.Width != width
            || unwind.giffile->SavedImages[slice].ImageDesc.Left != 0
            || unwind.giffile->SavedImages[slice].ImageDesc.Top != 0)
          signal_image_error ("Image in GIF file is not full size",
                              instantiator);

        interlace = unwind.giffile->SavedImages[slice].ImageDesc.Interlace;
        pass = 0;
        row = interlace ? InterlacedOffset[pass] : 0;
        eip = unwind.eimage + (width * height * 3 * slice);
        for (i = 0; i < height; i++)
          {
            if (interlace)
              if (row >= height) {
                row = InterlacedOffset[++pass];
                while (row >= height)
                  row = InterlacedOffset[++pass];
              }
            eip = unwind.eimage + (width * height * 3 * slice) + (row * width * 3);
            for (j = 0; j < width; j++)
              {
                unsigned char pixel = 
                  unwind.giffile->SavedImages[slice].RasterBits[(i * width) + j];
                *eip++ = cmo->Colors[pixel].Red;
                *eip++ = cmo->Colors[pixel].Green;
                *eip++ = cmo->Colors[pixel].Blue;
              }
            row += interlace ? InterlacedJumps[pass] : 1;
          }
      }

    /* now instantiate */
    MAYBE_DEVMETH (XDEVICE (ii->device),
                   init_image_instance_from_eimage,
                   (ii, width, height, unwind.giffile->ImageCount, unwind.eimage, dest_mask,
                    instantiator, domain));
  }

  /* We read the gif successfully. If we have more than one slice then
     animate the gif. */
  if (unwind.giffile->ImageCount > 1)
    {
    /* See if there is a timeout value. In theory there could be one
       for every image - but that makes the implementation way to
       complicated for now so we just take the first. */
      unsigned short timeout = 0;
      Lisp_Object tid;

      if (unwind.giffile->SavedImages[0].Function == GRAPHICS_EXT_FUNC_CODE
          &&
          unwind.giffile->SavedImages[0].ExtensionBlockCount)
        {
          timeout = (unsigned short)
            ((unwind.giffile->SavedImages[0].ExtensionBlocks[0].Bytes[2] << 8) + 
             unwind.giffile-> SavedImages[0].ExtensionBlocks[0].Bytes[1]) * 10;
        }

      /* Too short a timeout will crucify us performance-wise. */
      tid = add_glyph_animated_timeout (timeout > 10 ? timeout : 10, image_instance);

      if (!NILP (tid))
        IMAGE_INSTANCE_PIXMAP_TIMEOUT (ii) = XINT (tid);
    }
  
  unbind_to (speccount, Qnil);
}

#endif /* HAVE_GIF */

\f
#ifdef HAVE_PNG

/**********************************************************************
 *                             PNG                                    *
 **********************************************************************/
static void
png_validate (Lisp_Object instantiator)
{
  file_or_data_must_be_present (instantiator);
}

static Lisp_Object
png_normalize (Lisp_Object inst, Lisp_Object console_type)
{
  return simple_image_type_normalize (inst, console_type, Qpng);
}

static int
png_possible_dest_types (void)
{
  return IMAGE_COLOR_PIXMAP_MASK;
}

struct png_memory_storage
{
  CONST Extbyte *bytes;         /* The data       */
  Extcount len;                 /* How big is it? */
  int index;                    /* Where are we?  */
};

static void
png_read_from_memory(png_structp png_ptr, png_bytep data,
                     png_size_t length)
{
   struct png_memory_storage *tbr =
     (struct png_memory_storage *) png_get_io_ptr (png_ptr);

   if (length > (tbr->len - tbr->index))
     png_error (png_ptr, (png_const_charp) "Read Error");
   memcpy (data,tbr->bytes + tbr->index,length);
   tbr->index = tbr->index + length;
}

struct png_error_struct
{
  CONST char *err_str;
  jmp_buf setjmp_buffer;        /* for return to caller */
};

/* jh 98/03/12 - #### AARRRGH! libpng includes jmp_buf inside its own
   structure, and there are cases where the size can be different from
   between inside the library, and inside the code!  To do an end run
   around this, use our own error functions, and don't rely on things
   passed in the png_ptr to them.  This is an ugly hack and must
   go away when the lisp engine is threaded! */
static struct png_error_struct png_err_stct;

static void
png_error_func (png_structp png_ptr, png_const_charp msg)
{
  png_err_stct.err_str = msg;
  longjmp (png_err_stct.setjmp_buffer, 1);
}

static void
png_warning_func (png_structp png_ptr, png_const_charp msg)
{
  warn_when_safe (Qpng, Qinfo, "%s", msg);
}

struct png_unwind_data
{
  FILE *instream;
  unsigned char *eimage;
  png_structp png_ptr;
  png_infop info_ptr;
};

static Lisp_Object
png_instantiate_unwind (Lisp_Object unwind_obj)
{
  struct png_unwind_data *data =
    (struct png_unwind_data *) get_opaque_ptr (unwind_obj);

  free_opaque_ptr (unwind_obj);
  if (data->png_ptr)
    png_destroy_read_struct (&(data->png_ptr), &(data->info_ptr), (png_infopp)NULL);
  if (data->instream)
    fclose (data->instream);

  if (data->eimage) xfree(data->eimage);

  return Qnil;
}

static void
png_instantiate (Lisp_Object image_instance, Lisp_Object instantiator,
                 Lisp_Object pointer_fg, Lisp_Object pointer_bg,
                 int dest_mask, Lisp_Object domain)
{
  struct Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  struct png_unwind_data unwind;
  int speccount = specpdl_depth ();
  int height, width;
  struct png_memory_storage tbr;  /* Data to be read */

  /* PNG variables */
  png_structp png_ptr;
  png_infop info_ptr;

  /* Initialize all PNG structures */
  png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING, (void*)&png_err_stct,
                                    png_error_func, png_warning_func);
  if (!png_ptr)
    signal_image_error ("Error obtaining memory for png_read", instantiator);
  info_ptr = png_create_info_struct (png_ptr);
  if (!info_ptr)
    {
      png_destroy_read_struct (&png_ptr, (png_infopp)NULL, (png_infopp)NULL);
      signal_image_error ("Error obtaining memory for png_read", instantiator);
    }

  xzero (unwind);
  unwind.png_ptr = png_ptr;
  unwind.info_ptr = info_ptr;

  record_unwind_protect (png_instantiate_unwind, make_opaque_ptr (&unwind));

  /* This code is a mixture of stuff from Ben's GIF/JPEG stuff from
     this file, example.c from the libpng 0.81 distribution, and the
     pngtopnm sources. -WMP-
     */
  /* It has been further modified to handle the API changes for 0.96,
     and is no longer usable for previous versions. jh
  */

  /* Set the jmp_buf return context for png_error ... if this returns !0, then
     we ran into a problem somewhere, and need to clean up after ourselves. */
  if (setjmp (png_err_stct.setjmp_buffer))
    {
      /* Something blew up: just display the error (cleanup happens in the unwind) */
      signal_image_error_2 ("Error decoding PNG",
                             build_string(png_err_stct.err_str),
                             instantiator);
    }

  /* Initialize the IO layer and read in header information */
  {
    Lisp_Object data = find_keyword_in_vector (instantiator, Q_data);
    CONST Extbyte *bytes;
    Extcount len;

    assert (!NILP (data));

    /* #### This is a definite problem under Mule due to the amount of
       stack data it might allocate.  Need to think about using Lstreams */
    GET_STRING_BINARY_DATA_ALLOCA (data, bytes, len);
    tbr.bytes = bytes;
    tbr.len = len;
    tbr.index = 0;
    png_set_read_fn (png_ptr,(void *) &tbr, png_read_from_memory);
  }

  png_read_info (png_ptr, info_ptr);

  {
    int y;
    unsigned char **row_pointers;
    height = info_ptr->height;
    width = info_ptr->width;

    /* Wow, allocate all the memory.  Truly, exciting. */
    unwind.eimage = xnew_array_and_zero (unsigned char, width * height * 3);
    /* libpng expects that the image buffer passed in contains a
       picture to draw on top of if the png has any transparencies.
       This could be a good place to pass that in... */

    row_pointers  = xnew_array (png_byte *, height);

    for (y = 0; y < height; y++)
      row_pointers[y] = unwind.eimage + (width * 3 * y);

    {
      /* if the png specifies a background chunk, go ahead and
         use it, else use what we can get from the default face. */
      png_color_16 my_background, *image_background;
      Lisp_Object bkgd = Qnil;

      my_background.red   = 0x7fff;
      my_background.green = 0x7fff;
      my_background.blue  = 0x7fff;
      bkgd = FACE_BACKGROUND (Vdefault_face, domain);
      if (!COLOR_INSTANCEP (bkgd))
        {
          warn_when_safe (Qpng, Qinfo, "Couldn't get background color!");
        }
      else
        {
          struct Lisp_Color_Instance *c;
          Lisp_Object rgblist;

          c = XCOLOR_INSTANCE (bkgd);
          rgblist = MAYBE_LISP_DEVMETH (XDEVICE (c->device),
                                        color_instance_rgb_components,
                                        (c));
          my_background.red = XINT (XCAR (rgblist));
          my_background.green = XINT (XCAR (XCDR (rgblist)));
          my_background.blue = XINT (XCAR (XCDR (XCDR (rgblist))));
        }

      if (png_get_bKGD (png_ptr, info_ptr, &image_background))
        png_set_background (png_ptr, image_background,
                            PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
      else
        png_set_background (png_ptr, &my_background,
                            PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
    }

    /* Now that we're using EImage, ask for 8bit RGB triples for any type
       of image*/
    /* convert palette images to full RGB */
    if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
      png_set_expand (png_ptr);
    /* send grayscale images to RGB too */
    if (info_ptr->color_type == PNG_COLOR_TYPE_GRAY ||
        info_ptr->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
      png_set_gray_to_rgb (png_ptr);
    /* we can't handle alpha values */
    if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
      png_set_strip_alpha (png_ptr);
    /* tell libpng to strip 16 bit depth files down to 8 bits */
    if (info_ptr->bit_depth == 16)
      png_set_strip_16 (png_ptr);
    /* if the image is < 8 bits, pad it out */
    if (info_ptr->bit_depth < 8)
      {
        if (info_ptr->color_type == PNG_COLOR_TYPE_GRAY)
          png_set_expand (png_ptr);
        else
          png_set_packing (png_ptr);
      }

    png_read_image (png_ptr, row_pointers);
    png_read_end (png_ptr, info_ptr);

#ifdef PNG_SHOW_COMMENTS
    /* ####
     * I turn this off by default now, because the !%^@#!% comments
     * show up every time the image is instantiated, which can get
     * really really annoying.  There should be some way to pass this
     * type of data down into the glyph code, where you can get to it
     * from lisp anyway. - WMP
     */
    {
      int i;

      for (i = 0 ; i < info_ptr->num_text ; i++)
        {
          /* How paranoid do I have to be about no trailing NULLs, and
             using (int)info_ptr->text[i].text_length, and strncpy and a temp
             string somewhere? */

          warn_when_safe (Qpng, Qinfo, "%s - %s",
                          info_ptr->text[i].key,
                          info_ptr->text[i].text);
        }
    }
#endif

    xfree (row_pointers);
  }

  /* now instantiate */
  MAYBE_DEVMETH (XDEVICE (ii->device),
                 init_image_instance_from_eimage,
                 (ii, width, height, 1, unwind.eimage, dest_mask,
                  instantiator, domain));

  /* This will clean up everything else. */
  unbind_to (speccount, Qnil);
}

#endif /* HAVE_PNG */

\f
#ifdef HAVE_TIFF
#include "tiffio.h"

/**********************************************************************
 *                             TIFF                                   *
 **********************************************************************/
static void
tiff_validate (Lisp_Object instantiator)
{
  file_or_data_must_be_present (instantiator);
}

static Lisp_Object
tiff_normalize (Lisp_Object inst, Lisp_Object console_type)
{
  return simple_image_type_normalize (inst, console_type, Qtiff);
}

static int
tiff_possible_dest_types (void)
{
  return IMAGE_COLOR_PIXMAP_MASK;
}

struct tiff_unwind_data
{
  unsigned char *eimage;
  /* Object that holds the decoded data from a TIFF file */
  TIFF *tiff;
};

static Lisp_Object
tiff_instantiate_unwind (Lisp_Object unwind_obj)
{
  struct tiff_unwind_data *data =
    (struct tiff_unwind_data *) get_opaque_ptr (unwind_obj);

  free_opaque_ptr (unwind_obj);
  if (data->tiff)
    {
      TIFFClose(data->tiff);
    }
  if (data->eimage)
    xfree (data->eimage);

  return Qnil;
}

typedef struct tiff_memory_storage
{
  Extbyte *bytes;               /* The data       */
  Extcount len;                 /* How big is it? */
  int index;                    /* Where are we?  */
} tiff_memory_storage;

static size_t
tiff_memory_read(thandle_t data, tdata_t buf, tsize_t size)
{
  tiff_memory_storage *mem = (tiff_memory_storage*)data;

  if (size > (mem->len - mem->index))
    return (size_t) -1;
  memcpy(buf, mem->bytes + mem->index, size);
  mem->index = mem->index + size;
  return size;
}

static size_t tiff_memory_write(thandle_t data, tdata_t buf, tsize_t size)
{
  abort();
  return 0;                     /* Shut up warnings. */
}

static toff_t tiff_memory_seek(thandle_t data, toff_t off, int whence)
{
  tiff_memory_storage *mem = (tiff_memory_storage*)data;
  int newidx;
  switch(whence) {
  case SEEK_SET:
    newidx = off;
    break;
  case SEEK_END:
    newidx = mem->len + off;
    break;
  case SEEK_CUR:
    newidx = mem->index + off;
    break;
  default:
    fprintf(stderr,"Eh? invalid seek mode in tiff_memory_seek\n");
    return -1;
  }

  if ((newidx > mem->len) || (newidx < 0))
    return -1;

  mem->index = newidx;
  return newidx;
}

static int
tiff_memory_close(thandle_t data)
{
  return 0;
}

static int
tiff_map_noop(thandle_t data, tdata_t* pbase, toff_t* psize)
{
  return 0;
}

static void
tiff_unmap_noop(thandle_t data, tdata_t pbase, toff_t psize)
{
  return;
}

static toff_t
tiff_memory_size(thandle_t data)
{
  tiff_memory_storage *mem = (tiff_memory_storage*)data;
  return mem->len;
}

struct tiff_error_struct
{
#if HAVE_VSNPRINTF
  char err_str[256];
#else
  char err_str[1024];           /* return the error string */
#endif
  jmp_buf setjmp_buffer;        /* for return to caller */
};

/* jh 98/03/12 - ###This struct for passing data to the error functions
   is an ugly hack caused by the fact that libtiff (as of v3.4) doesn't
   have any place to store error func data.  This should be rectified
   before XEmacs gets threads! */
static struct tiff_error_struct tiff_err_data;

static void
tiff_error_func(CONST char *module, CONST char *fmt, ...)
{
  va_list vargs;

  va_start (vargs, fmt);
#if HAVE_VSNPRINTF
  vsnprintf (tiff_err_data.err_str, 255, fmt, vargs);
#else
  /* pray this doesn't overflow... */
  vsprintf (tiff_err_data.err_str, fmt, vargs);
#endif
  va_end (vargs);
  /* return to setjmp point */
  longjmp (tiff_err_data.setjmp_buffer, 1);
}

static void
tiff_warning_func(CONST char *module, CONST char *fmt, ...)
{
  va_list vargs;
#if HAVE_VSNPRINTF
  char warn_str[256];
#else
  char warn_str[1024];
#endif

  va_start (vargs, fmt);
#if HAVE_VSNPRINTF
  vsnprintf (warn_str, 255, fmt, vargs);
#else
  vsprintf (warn_str, fmt, vargs);
#endif
  va_end (vargs);
  warn_when_safe (Qtiff, Qinfo, "%s - %s",
                  module, warn_str);
}

static void
tiff_instantiate (Lisp_Object image_instance, Lisp_Object instantiator,
                  Lisp_Object pointer_fg, Lisp_Object pointer_bg,
                  int dest_mask, Lisp_Object domain)
{
  struct Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  tiff_memory_storage mem_struct;
  /* It is OK for the unwind data to be local to this function,
     because the unwind-protect is always executed when this
     stack frame is still valid. */
  struct tiff_unwind_data unwind;
  int speccount = specpdl_depth ();
  uint32 width, height;

  xzero (unwind);
  record_unwind_protect (tiff_instantiate_unwind, make_opaque_ptr (&unwind));

  /* set up error facilities */
  if (setjmp (tiff_err_data.setjmp_buffer))
    {
      /* An error was signaled. No clean up is needed, as unwind handles that
         for us.  Just pass the error along. */
      signal_image_error_2 ("TIFF decoding error",
                            build_string(tiff_err_data.err_str),
                            instantiator);
    }
  TIFFSetErrorHandler ((TIFFErrorHandler)tiff_error_func);
  TIFFSetWarningHandler ((TIFFErrorHandler)tiff_warning_func);
  {
    Lisp_Object data = find_keyword_in_vector (instantiator, Q_data);
    Extbyte *bytes;
    Extcount len;

    uint32 *raster;
    unsigned char *ep;

    assert (!NILP (data));

    /* #### This is a definite problem under Mule due to the amount of
       stack data it might allocate.  Think about Lstreams... */
    GET_STRING_BINARY_DATA_ALLOCA (data, bytes, len);
    mem_struct.bytes = bytes;
    mem_struct.len = len;
    mem_struct.index = 0;

    unwind.tiff = TIFFClientOpen ("memfile", "r", &mem_struct,
                                  (TIFFReadWriteProc)tiff_memory_read,
                                  (TIFFReadWriteProc)tiff_memory_write,
                                  tiff_memory_seek, tiff_memory_close, tiff_memory_size,
                                  tiff_map_noop, tiff_unmap_noop);
    if (!unwind.tiff)
      signal_image_error ("Insufficent memory to instantiate TIFF image", instantiator);

    TIFFGetField (unwind.tiff, TIFFTAG_IMAGEWIDTH, &width);
    TIFFGetField (unwind.tiff, TIFFTAG_IMAGELENGTH, &height);
    unwind.eimage = (unsigned char *) xmalloc (width * height * 3);

    /* ### This is little more than proof-of-concept/function testing.
       It needs to be reimplemented via scanline reads for both memory
       compactness. */
    raster = (uint32*) _TIFFmalloc (width * height * sizeof (uint32));
    if (raster != NULL)
      {
        int i,j;
        uint32 *rp;
        ep = unwind.eimage;
        rp = raster;
        if (TIFFReadRGBAImage (unwind.tiff, width, height, raster, 0))
          {
            for (i = height - 1;  i >= 0; i--)
              {
                /* This is to get around weirdness in the libtiff library where properly
                   made TIFFs will come out upside down.  libtiff bug or jhod-brainlock? */
                rp = raster + (i * width);
                for (j = 0; j < width; j++)
                  {
                    *ep++ = (unsigned char)TIFFGetR(*rp);
                    *ep++ = (unsigned char)TIFFGetG(*rp);
                    *ep++ = (unsigned char)TIFFGetB(*rp);
                    rp++;
                  }
              }
          }
        _TIFFfree (raster);
      } else
        signal_image_error ("Unable to allocate memory for TIFFReadRGBA", instantiator);

  }

  /* now instantiate */
  MAYBE_DEVMETH (XDEVICE (ii->device),
                 init_image_instance_from_eimage,
                 (ii, width, height, 1, unwind.eimage, dest_mask,
                  instantiator, domain));

  unbind_to (speccount, Qnil);
}

#endif /* HAVE_TIFF */

\f
/************************************************************************/
/*                            initialization                            */
/************************************************************************/

void
syms_of_glyphs_eimage (void)
{
}

void
image_instantiator_format_create_glyphs_eimage (void)
{
  /* image-instantiator types */
#ifdef HAVE_JPEG
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (jpeg, "jpeg");

  IIFORMAT_HAS_METHOD (jpeg, validate);
  IIFORMAT_HAS_METHOD (jpeg, normalize);
  IIFORMAT_HAS_METHOD (jpeg, possible_dest_types);
  IIFORMAT_HAS_METHOD (jpeg, instantiate);

  IIFORMAT_VALID_KEYWORD (jpeg, Q_data, check_valid_string);
  IIFORMAT_VALID_KEYWORD (jpeg, Q_file, check_valid_string);
#endif

#ifdef HAVE_GIF
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (gif, "gif");

  IIFORMAT_HAS_METHOD (gif, validate);
  IIFORMAT_HAS_METHOD (gif, normalize);
  IIFORMAT_HAS_METHOD (gif, possible_dest_types);
  IIFORMAT_HAS_METHOD (gif, instantiate);

  IIFORMAT_VALID_KEYWORD (gif, Q_data, check_valid_string);
  IIFORMAT_VALID_KEYWORD (gif, Q_file, check_valid_string);
#endif

#ifdef HAVE_PNG
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (png, "png");

  IIFORMAT_HAS_METHOD (png, validate);
  IIFORMAT_HAS_METHOD (png, normalize);
  IIFORMAT_HAS_METHOD (png, possible_dest_types);
  IIFORMAT_HAS_METHOD (png, instantiate);

  IIFORMAT_VALID_KEYWORD (png, Q_data, check_valid_string);
  IIFORMAT_VALID_KEYWORD (png, Q_file, check_valid_string);
#endif

#ifdef HAVE_TIFF
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (tiff, "tiff");

  IIFORMAT_HAS_METHOD (tiff, validate);
  IIFORMAT_HAS_METHOD (tiff, normalize);
  IIFORMAT_HAS_METHOD (tiff, possible_dest_types);
  IIFORMAT_HAS_METHOD (tiff, instantiate);

  IIFORMAT_VALID_KEYWORD (tiff, Q_data, check_valid_string);
  IIFORMAT_VALID_KEYWORD (tiff, Q_file, check_valid_string);
#endif

}

void
vars_of_glyphs_eimage (void)
{
#ifdef HAVE_JPEG
  Fprovide (Qjpeg);
#endif

#ifdef HAVE_GIF
  Fprovide (Qgif);
#endif

#ifdef HAVE_PNG
  Fprovide (Qpng);
#endif

#ifdef HAVE_TIFF
  Fprovide (Qtiff);
#endif

}