LuaTeX, pdfTeX, XeTeX: Avoid PNG warnings

git-svn-id: svn://tug.org/texlive/trunk@34978 c570f23f-e606-0410-a88d-b1316a301751

3 files changed, 18 insertions, 3 deletions

diff --git a/Build/source/texk/web2c/luatexdir/image/writepng.w b/Build/source/texk/web2c/luatexdir/image/writepng.w
index 5e2f34e1570..50eec4636f2 100644
--- a/Build/source/texk/web2c/luatexdir/image/writepng.w
+++ b/Build/source/texk/web2c/luatexdir/image/writepng.w
@@ -45,6 +45,11 @@ static void close_and_cleanup_png(image_dict * idict)
 }
 
 @ @c
+static void warn(png_structp png_ptr, png_const_charp msg)
+{
+  (void)png_ptr; (void)msg; /* Make compiler happy */
+}
+
 void read_png_info(image_dict * idict, img_readtype_e readtype)
 {
     png_structp png_p;
@@ -59,7 +64,7 @@ void read_png_info(image_dict * idict, img_readtype_e readtype)
     assert(img_png_ptr(idict) == NULL);
     img_png_ptr(idict) = xtalloc(1, png_img_struct);
     if ((png_p = png_create_read_struct(PNG_LIBPNG_VER_STRING,
-                                        NULL, NULL, NULL)) == NULL)
+                                        NULL, NULL, warn)) == NULL)
         luatex_fail("libpng: png_create_read_struct() failed");
     img_png_png_ptr(idict) = png_p;
     if ((info_p = png_create_info_struct(png_p)) == NULL)
diff --git a/Build/source/texk/web2c/pdftexdir/writepng.c b/Build/source/texk/web2c/pdftexdir/writepng.c
index 6371e934089..5713880f6e1 100644
--- a/Build/source/texk/web2c/pdftexdir/writepng.c
+++ b/Build/source/texk/web2c/pdftexdir/writepng.c
@@ -22,12 +22,17 @@ with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 static int transparent_page_group = 0;
 
+static void warn(png_structp png_ptr, png_const_charp msg)
+{
+  (void)png_ptr; (void)msg; /* Make compiler happy */
+}
+
 void read_png_info(integer img)
 {
     FILE *png_file = xfopen(img_name(img), FOPEN_RBIN_MODE);
 
     if ((png_ptr(img) = png_create_read_struct(PNG_LIBPNG_VER_STRING,
-                                               NULL, NULL, NULL)) == NULL)
+                                               NULL, NULL, warn)) == NULL)
         pdftex_fail("libpng: png_create_read_struct() failed");
     if ((png_info(img) = png_create_info_struct(png_ptr(img))) == NULL)
         pdftex_fail("libpng: png_create_info_struct() failed");
diff --git a/Build/source/texk/web2c/xetexdir/image/pngimage.c b/Build/source/texk/web2c/xetexdir/image/pngimage.c
index 27e74fbbfc3..ec677528130 100644
--- a/Build/source/texk/web2c/xetexdir/image/pngimage.c
+++ b/Build/source/texk/web2c/xetexdir/image/pngimage.c
@@ -94,6 +94,11 @@
 #define PDF_TRANS_TYPE_BINARY 1
 #define PDF_TRANS_TYPE_ALPHA  2
 
+static void warn(png_structp png_ptr, png_const_charp msg)
+{
+  (void)png_ptr; (void)msg; /* Make compiler happy */
+}
+
 int
 check_for_png (FILE *png_file) 
 {
@@ -118,7 +123,7 @@ png_scan_file (struct png_info *info, FILE *png_file)
   png_uint_32 width, height;
   
   rewind (png_file);
-  png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+  png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, warn);
   if (png_ptr == NULL || 
       (png_info_ptr = png_create_info_struct (png_ptr)) == NULL) {
     fprintf(stderr, "WARNING: %s: Creating Libpng read/info struct failed.", PNG_DEBUG_STR);