ref: 85bf278b42fe3059dc8774d6f257dbc07ac50679
parent: 6aa746d4788e43727f93ed58581ef13f45f5e4b1
author: giles <giles@ded80894-8fb9-0310-811b-c03f3676ab4d>
date: Wed Aug 7 08:50:33 EDT 2002
Use callbacks for writing png data out to a file. This is necessary when dynamically linking to libpng on win32 when different run-times are used for each library. Patch from Russell Lang. git-svn-id: http://svn.ghostscript.com/jbig2dec/trunk@192 ded80894-8fb9-0310-811b-c03f3676ab4d
--- a/jbig2_image_png.c
+++ b/jbig2_image_png.c
@@ -8,7 +8,7 @@
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
- $Id: jbig2_image_png.c,v 1.8 2002/08/06 11:31:53 giles Exp $
+ $Id: jbig2_image_png.c,v 1.9 2002/08/07 12:50:33 giles Exp $
*/
#ifdef HAVE_CONFIG_H
@@ -26,6 +26,26 @@
/* take an image structure and write it out in png format */
+static void
+jbig2_png_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{+ png_size_t check;
+
+ check = fwrite(data, 1, length, (png_FILE_p)png_ptr->io_ptr);
+ if (check != length) {+ png_error(png_ptr, "Write Error");
+ }
+}
+
+static void
+jbig2_png_flush(png_structp png_ptr)
+{+ png_FILE_p io_ptr;
+ io_ptr = (png_FILE_p)CVT_PTR((png_ptr->io_ptr));
+ if (io_ptr != NULL)
+ fflush(io_ptr);
+}
+
int jbig2_image_write_png_file(Jbig2Image *image, char *filename)
{FILE *out;
@@ -73,11 +93,13 @@
return 4;
}
- /* note that this doesn't work linking dynamically to libpng on win32
+ /* png_init_io() doesn't work linking dynamically to libpng on win32
one has to either link statically or use callbacks because of runtime
variations */
- png_init_io(png, out);
-
+ /* png_init_io(png, out); */
+ png_set_write_fn(png, (png_voidp)out, jbig2_png_write_data,
+ jbig2_png_flush);
+
/* now we fill out the info structure with our format data */
png_set_IHDR(png, info, image->width, image->height,
1, PNG_COLOR_TYPE_GRAY, PNG_INTERLACE_NONE,