Remove damned ancient DOS line endings from Irrlicht. Hopefully I did not go overboard.

1 files changed, 400 insertions, 400 deletions

diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.c
index 8373c16..f07f4a8 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.c
@@ -1,400 +1,400 @@
-/*---------------------------------------------------------------------------

-

-   wpng - simple PNG-writing program                             writepng.c

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program 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 of the License, or

-      (at your option) any later version.

-

-      This program 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 this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-

-#include <stdlib.h>     /* for exit() prototype */

-

-#include "png.h"        /* libpng header; includes zlib.h and setjmp.h */

-#include "writepng.h"   /* typedefs, common macros, public prototypes */

-

-

-/* local prototype */

-

-static void writepng_error_handler(png_structp png_ptr, png_const_charp msg);

-

-

-

-void writepng_version_info(void)

-{

-  fprintf(stderr, "   Compiled with libpng %s; using libpng %s.\n",

-    PNG_LIBPNG_VER_STRING, png_libpng_ver);

-  fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",

-    ZLIB_VERSION, zlib_version);

-}

-

-

-

-

-/* returns 0 for success, 2 for libpng problem, 4 for out of memory, 11 for

- *  unexpected pnmtype; note that outfile might be stdout */

-

-int writepng_init(mainprog_info *mainprog_ptr)

-{

-    png_structp  png_ptr;       /* note:  temporary variables! */

-    png_infop  info_ptr;

-    int color_type, interlace_type;

-

-

-    /* could also replace libpng warning-handler (final NULL), but no need: */

-

-    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,

-      writepng_error_handler, NULL);

-    if (!png_ptr)

-        return 4;   /* out of memory */

-

-    info_ptr = png_create_info_struct(png_ptr);

-    if (!info_ptr) {

-        png_destroy_write_struct(&png_ptr, NULL);

-        return 4;   /* out of memory */

-    }

-

-

-    /* setjmp() must be called in every function that calls a PNG-writing

-     * libpng function, unless an alternate error handler was installed--

-     * but compatible error handlers must either use longjmp() themselves

-     * (as in this program) or some other method to return control to

-     * application code, so here we go: */

-

-    if (setjmp(mainprog_ptr->jmpbuf)) {

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-        return 2;

-    }

-

-

-    /* make sure outfile is (re)opened in BINARY mode */

-

-    png_init_io(png_ptr, mainprog_ptr->outfile);

-

-

-    /* set the compression levels--in general, always want to leave filtering

-     * turned on (except for palette images) and allow all of the filters,

-     * which is the default; want 32K zlib window, unless entire image buffer

-     * is 16K or smaller (unknown here)--also the default; usually want max

-     * compression (NOT the default); and remaining compression flags should

-     * be left alone */

-

-    png_set_compression_level(png_ptr, Z_BEST_COMPRESSION);

-/*

-    >> this is default for no filtering; Z_FILTERED is default otherwise:

-    png_set_compression_strategy(png_ptr, Z_DEFAULT_STRATEGY);

-    >> these are all defaults:

-    png_set_compression_mem_level(png_ptr, 8);

-    png_set_compression_window_bits(png_ptr, 15);

-    png_set_compression_method(png_ptr, 8);

- */

-

-

-    /* set the image parameters appropriately */

-

-    if (mainprog_ptr->pnmtype == 5)

-        color_type = PNG_COLOR_TYPE_GRAY;

-    else if (mainprog_ptr->pnmtype == 6)

-        color_type = PNG_COLOR_TYPE_RGB;

-    else if (mainprog_ptr->pnmtype == 8)

-        color_type = PNG_COLOR_TYPE_RGB_ALPHA;

-    else {

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-        return 11;

-    }

-

-    interlace_type = mainprog_ptr->interlaced? PNG_INTERLACE_ADAM7 :

-                                               PNG_INTERLACE_NONE;

-

-    png_set_IHDR(png_ptr, info_ptr, mainprog_ptr->width, mainprog_ptr->height,

-      mainprog_ptr->sample_depth, color_type, interlace_type,

-      PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);

-

-    if (mainprog_ptr->gamma > 0.0)

-        png_set_gAMA(png_ptr, info_ptr, mainprog_ptr->gamma);

-

-    if (mainprog_ptr->have_bg) {   /* we know it's RGBA, not gray+alpha */

-        png_color_16  background;

-

-        background.red = mainprog_ptr->bg_red;

-        background.green = mainprog_ptr->bg_green;

-        background.blue = mainprog_ptr->bg_blue;

-        png_set_bKGD(png_ptr, info_ptr, &background);

-    }

-

-    if (mainprog_ptr->have_time) {

-        png_time  modtime;

-

-        png_convert_from_time_t(&modtime, mainprog_ptr->modtime);

-        png_set_tIME(png_ptr, info_ptr, &modtime);

-    }

-

-    if (mainprog_ptr->have_text) {

-        png_text  text[6];

-        int  num_text = 0;

-

-        if (mainprog_ptr->have_text & TEXT_TITLE) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "Title";

-            text[num_text].text = mainprog_ptr->title;

-            ++num_text;

-        }

-        if (mainprog_ptr->have_text & TEXT_AUTHOR) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "Author";

-            text[num_text].text = mainprog_ptr->author;

-            ++num_text;

-        }

-        if (mainprog_ptr->have_text & TEXT_DESC) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "Description";

-            text[num_text].text = mainprog_ptr->desc;

-            ++num_text;

-        }

-        if (mainprog_ptr->have_text & TEXT_COPY) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "Copyright";

-            text[num_text].text = mainprog_ptr->copyright;

-            ++num_text;

-        }

-        if (mainprog_ptr->have_text & TEXT_EMAIL) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "E-mail";

-            text[num_text].text = mainprog_ptr->email;

-            ++num_text;

-        }

-        if (mainprog_ptr->have_text & TEXT_URL) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "URL";

-            text[num_text].text = mainprog_ptr->url;

-            ++num_text;

-        }

-        png_set_text(png_ptr, info_ptr, text, num_text);

-    }

-

-

-    /* write all chunks up to (but not including) first IDAT */

-

-    png_write_info(png_ptr, info_ptr);

-

-

-    /* if we wanted to write any more text info *after* the image data, we

-     * would set up text struct(s) here and call png_set_text() again, with

-     * just the new data; png_set_tIME() could also go here, but it would

-     * have no effect since we already called it above (only one tIME chunk

-     * allowed) */

-

-

-    /* set up the transformations:  for now, just pack low-bit-depth pixels

-     * into bytes (one, two or four pixels per byte) */

-

-    png_set_packing(png_ptr);

-/*  png_set_shift(png_ptr, &sig_bit);  to scale low-bit-depth values */

-

-

-    /* make sure we save our pointers for use in writepng_encode_image() */

-

-    mainprog_ptr->png_ptr = png_ptr;

-    mainprog_ptr->info_ptr = info_ptr;

-

-

-    /* OK, that's all we need to do for now; return happy */

-

-    return 0;

-}

-

-

-

-

-

-/* returns 0 for success, 2 for libpng (longjmp) problem */

-

-int writepng_encode_image(mainprog_info *mainprog_ptr)

-{

-    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;

-    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;

-

-

-    /* as always, setjmp() must be called in every function that calls a

-     * PNG-writing libpng function */

-

-    if (setjmp(mainprog_ptr->jmpbuf)) {

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-        mainprog_ptr->png_ptr = NULL;

-        mainprog_ptr->info_ptr = NULL;

-        return 2;

-    }

-

-

-    /* and now we just write the whole image; libpng takes care of interlacing

-     * for us */

-

-    png_write_image(png_ptr, mainprog_ptr->row_pointers);

-

-

-    /* since that's it, we also close out the end of the PNG file now--if we

-     * had any text or time info to write after the IDATs, second argument

-     * would be info_ptr, but we optimize slightly by sending NULL pointer: */

-

-    png_write_end(png_ptr, NULL);

-

-    return 0;

-}

-

-

-

-

-

-/* returns 0 if succeeds, 2 if libpng problem */

-

-int writepng_encode_row(mainprog_info *mainprog_ptr)  /* NON-interlaced only! */

-{

-    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;

-    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;

-

-

-    /* as always, setjmp() must be called in every function that calls a

-     * PNG-writing libpng function */

-

-    if (setjmp(mainprog_ptr->jmpbuf)) {

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-        mainprog_ptr->png_ptr = NULL;

-        mainprog_ptr->info_ptr = NULL;

-        return 2;

-    }

-

-

-    /* image_data points at our one row of image data */

-

-    png_write_row(png_ptr, mainprog_ptr->image_data);

-

-    return 0;

-}

-

-

-

-

-

-/* returns 0 if succeeds, 2 if libpng problem */

-

-int writepng_encode_finish(mainprog_info *mainprog_ptr)   /* NON-interlaced! */

-{

-    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;

-    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;

-

-

-    /* as always, setjmp() must be called in every function that calls a

-     * PNG-writing libpng function */

-

-    if (setjmp(mainprog_ptr->jmpbuf)) {

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-        mainprog_ptr->png_ptr = NULL;

-        mainprog_ptr->info_ptr = NULL;

-        return 2;

-    }

-

-

-    /* close out PNG file; if we had any text or time info to write after

-     * the IDATs, second argument would be info_ptr: */

-

-    png_write_end(png_ptr, NULL);

-

-    return 0;

-}

-

-

-

-

-

-void writepng_cleanup(mainprog_info *mainprog_ptr)

-{

-    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;

-    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;

-

-    if (png_ptr && info_ptr)

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-}

-

-

-

-

-

-static void writepng_error_handler(png_structp png_ptr, png_const_charp msg)

-{

-    mainprog_info  *mainprog_ptr;

-

-    /* This function, aside from the extra step of retrieving the "error

-     * pointer" (below) and the fact that it exists within the application

-     * rather than within libpng, is essentially identical to libpng's

-     * default error handler.  The second point is critical:  since both

-     * setjmp() and longjmp() are called from the same code, they are

-     * guaranteed to have compatible notions of how big a jmp_buf is,

-     * regardless of whether _BSD_SOURCE or anything else has (or has not)

-     * been defined. */

-

-    fprintf(stderr, "writepng libpng error: %s\n", msg);

-    fflush(stderr);

-

-    mainprog_ptr = png_get_error_ptr(png_ptr);

-    if (mainprog_ptr == NULL) {         /* we are completely hosed now */

-        fprintf(stderr,

-          "writepng severe error:  jmpbuf not recoverable; terminating.\n");

-        fflush(stderr);

-        exit(99);

-    }

-

-    /* Now we have our data structure we can use the information in it

-     * to return control to our own higher level code (all the points

-     * where 'setjmp' is called in this file.)  This will work with other

-     * error handling mechanisms as well - libpng always calls png_error

-     * when it can proceed no further, thus, so long as the error handler

-     * is intercepted, application code can do its own error recovery.

-     */

-    longjmp(mainprog_ptr->jmpbuf, 1);

-}

+/*---------------------------------------------------------------------------
+
+   wpng - simple PNG-writing program                             writepng.c
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program 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 of the License, or
+      (at your option) any later version.
+
+      This program 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 this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+
+#include <stdlib.h>     /* for exit() prototype */
+
+#include "png.h"        /* libpng header; includes zlib.h and setjmp.h */
+#include "writepng.h"   /* typedefs, common macros, public prototypes */
+
+
+/* local prototype */
+
+static void writepng_error_handler(png_structp png_ptr, png_const_charp msg);
+
+
+
+void writepng_version_info(void)
+{
+  fprintf(stderr, "   Compiled with libpng %s; using libpng %s.\n",
+    PNG_LIBPNG_VER_STRING, png_libpng_ver);
+  fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",
+    ZLIB_VERSION, zlib_version);
+}
+
+
+
+
+/* returns 0 for success, 2 for libpng problem, 4 for out of memory, 11 for
+ *  unexpected pnmtype; note that outfile might be stdout */
+
+int writepng_init(mainprog_info *mainprog_ptr)
+{
+    png_structp  png_ptr;       /* note:  temporary variables! */
+    png_infop  info_ptr;
+    int color_type, interlace_type;
+
+
+    /* could also replace libpng warning-handler (final NULL), but no need: */
+
+    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,
+      writepng_error_handler, NULL);
+    if (!png_ptr)
+        return 4;   /* out of memory */
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        png_destroy_write_struct(&png_ptr, NULL);
+        return 4;   /* out of memory */
+    }
+
+
+    /* setjmp() must be called in every function that calls a PNG-writing
+     * libpng function, unless an alternate error handler was installed--
+     * but compatible error handlers must either use longjmp() themselves
+     * (as in this program) or some other method to return control to
+     * application code, so here we go: */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        return 2;
+    }
+
+
+    /* make sure outfile is (re)opened in BINARY mode */
+
+    png_init_io(png_ptr, mainprog_ptr->outfile);
+
+
+    /* set the compression levels--in general, always want to leave filtering
+     * turned on (except for palette images) and allow all of the filters,
+     * which is the default; want 32K zlib window, unless entire image buffer
+     * is 16K or smaller (unknown here)--also the default; usually want max
+     * compression (NOT the default); and remaining compression flags should
+     * be left alone */
+
+    png_set_compression_level(png_ptr, Z_BEST_COMPRESSION);
+/*
+    >> this is default for no filtering; Z_FILTERED is default otherwise:
+    png_set_compression_strategy(png_ptr, Z_DEFAULT_STRATEGY);
+    >> these are all defaults:
+    png_set_compression_mem_level(png_ptr, 8);
+    png_set_compression_window_bits(png_ptr, 15);
+    png_set_compression_method(png_ptr, 8);
+ */
+
+
+    /* set the image parameters appropriately */
+
+    if (mainprog_ptr->pnmtype == 5)
+        color_type = PNG_COLOR_TYPE_GRAY;
+    else if (mainprog_ptr->pnmtype == 6)
+        color_type = PNG_COLOR_TYPE_RGB;
+    else if (mainprog_ptr->pnmtype == 8)
+        color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+    else {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        return 11;
+    }
+
+    interlace_type = mainprog_ptr->interlaced? PNG_INTERLACE_ADAM7 :
+                                               PNG_INTERLACE_NONE;
+
+    png_set_IHDR(png_ptr, info_ptr, mainprog_ptr->width, mainprog_ptr->height,
+      mainprog_ptr->sample_depth, color_type, interlace_type,
+      PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
+
+    if (mainprog_ptr->gamma > 0.0)
+        png_set_gAMA(png_ptr, info_ptr, mainprog_ptr->gamma);
+
+    if (mainprog_ptr->have_bg) {   /* we know it's RGBA, not gray+alpha */
+        png_color_16  background;
+
+        background.red = mainprog_ptr->bg_red;
+        background.green = mainprog_ptr->bg_green;
+        background.blue = mainprog_ptr->bg_blue;
+        png_set_bKGD(png_ptr, info_ptr, &background);
+    }
+
+    if (mainprog_ptr->have_time) {
+        png_time  modtime;
+
+        png_convert_from_time_t(&modtime, mainprog_ptr->modtime);
+        png_set_tIME(png_ptr, info_ptr, &modtime);
+    }
+
+    if (mainprog_ptr->have_text) {
+        png_text  text[6];
+        int  num_text = 0;
+
+        if (mainprog_ptr->have_text & TEXT_TITLE) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Title";
+            text[num_text].text = mainprog_ptr->title;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_AUTHOR) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Author";
+            text[num_text].text = mainprog_ptr->author;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_DESC) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Description";
+            text[num_text].text = mainprog_ptr->desc;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_COPY) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Copyright";
+            text[num_text].text = mainprog_ptr->copyright;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_EMAIL) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "E-mail";
+            text[num_text].text = mainprog_ptr->email;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_URL) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "URL";
+            text[num_text].text = mainprog_ptr->url;
+            ++num_text;
+        }
+        png_set_text(png_ptr, info_ptr, text, num_text);
+    }
+
+
+    /* write all chunks up to (but not including) first IDAT */
+
+    png_write_info(png_ptr, info_ptr);
+
+
+    /* if we wanted to write any more text info *after* the image data, we
+     * would set up text struct(s) here and call png_set_text() again, with
+     * just the new data; png_set_tIME() could also go here, but it would
+     * have no effect since we already called it above (only one tIME chunk
+     * allowed) */
+
+
+    /* set up the transformations:  for now, just pack low-bit-depth pixels
+     * into bytes (one, two or four pixels per byte) */
+
+    png_set_packing(png_ptr);
+/*  png_set_shift(png_ptr, &sig_bit);  to scale low-bit-depth values */
+
+
+    /* make sure we save our pointers for use in writepng_encode_image() */
+
+    mainprog_ptr->png_ptr = png_ptr;
+    mainprog_ptr->info_ptr = info_ptr;
+
+
+    /* OK, that's all we need to do for now; return happy */
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 for success, 2 for libpng (longjmp) problem */
+
+int writepng_encode_image(mainprog_info *mainprog_ptr)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* and now we just write the whole image; libpng takes care of interlacing
+     * for us */
+
+    png_write_image(png_ptr, mainprog_ptr->row_pointers);
+
+
+    /* since that's it, we also close out the end of the PNG file now--if we
+     * had any text or time info to write after the IDATs, second argument
+     * would be info_ptr, but we optimize slightly by sending NULL pointer: */
+
+    png_write_end(png_ptr, NULL);
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 if succeeds, 2 if libpng problem */
+
+int writepng_encode_row(mainprog_info *mainprog_ptr)  /* NON-interlaced only! */
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* image_data points at our one row of image data */
+
+    png_write_row(png_ptr, mainprog_ptr->image_data);
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 if succeeds, 2 if libpng problem */
+
+int writepng_encode_finish(mainprog_info *mainprog_ptr)   /* NON-interlaced! */
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* close out PNG file; if we had any text or time info to write after
+     * the IDATs, second argument would be info_ptr: */
+
+    png_write_end(png_ptr, NULL);
+
+    return 0;
+}
+
+
+
+
+
+void writepng_cleanup(mainprog_info *mainprog_ptr)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+    if (png_ptr && info_ptr)
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+}
+
+
+
+
+
+static void writepng_error_handler(png_structp png_ptr, png_const_charp msg)
+{
+    mainprog_info  *mainprog_ptr;
+
+    /* This function, aside from the extra step of retrieving the "error
+     * pointer" (below) and the fact that it exists within the application
+     * rather than within libpng, is essentially identical to libpng's
+     * default error handler.  The second point is critical:  since both
+     * setjmp() and longjmp() are called from the same code, they are
+     * guaranteed to have compatible notions of how big a jmp_buf is,
+     * regardless of whether _BSD_SOURCE or anything else has (or has not)
+     * been defined. */
+
+    fprintf(stderr, "writepng libpng error: %s\n", msg);
+    fflush(stderr);
+
+    mainprog_ptr = png_get_error_ptr(png_ptr);
+    if (mainprog_ptr == NULL) {         /* we are completely hosed now */
+        fprintf(stderr,
+          "writepng severe error:  jmpbuf not recoverable; terminating.\n");
+        fflush(stderr);
+        exit(99);
+    }
+
+    /* Now we have our data structure we can use the information in it
+     * to return control to our own higher level code (all the points
+     * where 'setjmp' is called in this file.)  This will work with other
+     * error handling mechanisms as well - libpng always calls png_error
+     * when it can proceed no further, thus, so long as the error handler
+     * is intercepted, application code can do its own error recovery.
+     */
+    longjmp(mainprog_ptr->jmpbuf, 1);
+}