--- src/vigra_impex/png.cxx.orig	2009-12-20 15:32:28.000000000 +0000
+++ src/vigra_impex/png.cxx	2011-12-06 22:18:40.000000000 +0000
@@ -65,10 +65,20 @@
 #include <png.h>
 }
 
+#define STRINGIFY(m_argument) #m_argument
+
 #if PNG_LIBPNG_VER < 10201
 #error "please update your libpng to at least 1.2.1"
 #endif
 
+#if PNG_LIBPNG_VER >= 10400
+#define PNG_SET_EXPAND_GRAY_1_2_4_TO_8_NAME png_set_expand_gray_1_2_4_to_8
+#else
+#define PNG_SET_EXPAND_GRAY_1_2_4_TO_8_NAME png_set_gray_1_2_4_to_8
+#endif
+#define PNG_SET_EXPAND_GRAY_1_2_4_TO_8_FUNCTION_NAME STRINGIFY(PNG_SET_EXPAND_GRAY_1_2_4_TO_8_NAME)
+#define PNG_SET_EXPAND_GRAY_1_2_4_TO_8(m_image) PNG_SET_EXPAND_GRAY_1_2_4_TO_8_NAME(m_image)
+
 // TODO: per-scanline reading/writing
 
 namespace {
@@ -81,7 +91,7 @@
 static void PngError( png_structp png_ptr, png_const_charp error_msg )
 {
     png_error_message = std::string(error_msg);
-    longjmp( png_ptr->jmpbuf, 1 );
+    longjmp( png_jmpbuf(png_ptr), 1 );
 }
 
 // called on non-fatal errors
@@ -203,9 +213,9 @@
         // check if the file is a png file
         const unsigned int sig_size = 8;
         png_byte sig[sig_size];
-        std::fread( sig, sig_size, 1, file.get() );
+        std::size_t readCount = std::fread( sig, sig_size, 1, file.get() );
         const int no_png = png_sig_cmp( sig, 0, sig_size );
-        vigra_precondition( !no_png, "given file is not a png file.");
+        vigra_precondition( (readCount == 1) && !no_png, "given file is not a png file.");
 
         // create png read struct with user defined handlers
         png = png_create_read_struct( PNG_LIBPNG_VER_STRING, NULL,
@@ -213,7 +223,7 @@
         vigra_postcondition( png != 0, "could not create the read struct." );
 
         // create info struct
-        if (setjmp(png->jmpbuf)) {
+        if (setjmp(png_jmpbuf(png))) {
             png_destroy_read_struct( &png, &info, NULL );
             vigra_postcondition( false, png_error_message.insert(0, "error in png_create_info_struct(): ").c_str() );
         }
@@ -221,14 +231,14 @@
         vigra_postcondition( info != 0, "could not create the info struct." );
 
         // init png i/o
-        if (setjmp(png->jmpbuf)) {
+        if (setjmp(png_jmpbuf(png))) {
             png_destroy_read_struct( &png, &info, NULL );
             vigra_postcondition( false, png_error_message.insert(0, "error in png_init_io(): ").c_str() );
         }
         png_init_io( png, file.get() );
 
         // specify that the signature was already read
-        if (setjmp(png->jmpbuf)) {
+        if (setjmp(png_jmpbuf(png))) {
             png_destroy_read_struct( &png, &info, NULL );
             vigra_postcondition( false, png_error_message.insert(0, "error in png_set_sig_bytes(): ").c_str() );
         }
@@ -244,13 +254,13 @@
     void PngDecoderImpl::init()
     {
         // read all chunks up to the image data
-        if (setjmp(png->jmpbuf))
+        if (setjmp(png_jmpbuf(png)))
             vigra_postcondition( false, png_error_message.insert(0, "error in png_read_info(): ").c_str() );
         png_read_info( png, info );
 
         // pull over the header fields
         int interlace_method, compression_method, filter_method;
-        if (setjmp(png->jmpbuf))
+        if (setjmp(png_jmpbuf(png)))
             vigra_postcondition( false, png_error_message.insert(0, "error in png_get_IHDR(): ").c_str() );
         png_get_IHDR( png, info, &width, &height, &bit_depth, &color_type,
                       &interlace_method, &compression_method, &filter_method );
@@ -264,7 +274,7 @@
 
         // transform palette to rgb
         if ( color_type == PNG_COLOR_TYPE_PALETTE) {
-            if (setjmp(png->jmpbuf))
+            if (setjmp(png_jmpbuf(png)))
                 vigra_postcondition( false, png_error_message.insert(0, "error in png_palette_to_rgb(): ").c_str() );
             png_set_palette_to_rgb(png);
             color_type = PNG_COLOR_TYPE_RGB;
@@ -273,9 +283,9 @@
 
         // expand gray values to at least one byte size
         if ( color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8 ) {
-            if (setjmp(png->jmpbuf))
-                vigra_postcondition( false,png_error_message.insert(0, "error in png_set_gray_1_2_4_to_8(): ").c_str());
-            png_set_gray_1_2_4_to_8(png);
+            if (setjmp(png_jmpbuf(png)))
+                vigra_postcondition( false, png_error_message.insert(0, "error in " PNG_SET_EXPAND_GRAY_1_2_4_TO_8_FUNCTION_NAME " (): ").c_str());
+            PNG_SET_EXPAND_GRAY_1_2_4_TO_8(png);
             bit_depth = 8;
         }
 
@@ -283,7 +293,7 @@
 #if 0
         // strip alpha channel
         if ( color_type & PNG_COLOR_MASK_ALPHA ) {
-            if (setjmp(png->jmpbuf))
+            if (setjmp(png_jmpbuf(png)))
                 vigra_postcondition( false, png_error_message.insert(0, "error in png_set_strip_alpha(): ").c_str() );
             png_set_strip_alpha(png);
             color_type ^= PNG_COLOR_MASK_ALPHA;
@@ -325,9 +335,13 @@
 #if (PNG_LIBPNG_VER > 10008) && defined(PNG_READ_iCCP_SUPPORTED)
         char * dummyName;
         int dummyCompType;
+#if (PNG_LIBPNG_VER < 10500)
         char * profilePtr;
+#else
+        png_byte * profilePtr;
+#endif
         png_uint_32 profileLen;
-        if (info->valid & PNG_INFO_iCCP) {
+        if (png_get_valid( png, info, PNG_INFO_iCCP )) {
             png_get_iCCP(png, info, &dummyName, &dummyCompType, &profilePtr, &profileLen) ;
             iccProfilePtr = (unsigned char *) profilePtr;
             iccProfileLength = profileLen;
@@ -340,7 +354,7 @@
         // image gamma
         double image_gamma = 0.45455;
         if ( png_get_valid( png, info, PNG_INFO_gAMA ) ) {
-            if (setjmp(png->jmpbuf))
+            if (setjmp(png_jmpbuf(png)))
                 vigra_postcondition( false, png_error_message.insert(0, "error in png_get_gAMA(): ").c_str() );
             png_get_gAMA( png, info, &image_gamma );
         }
@@ -349,26 +363,26 @@
         double screen_gamma = 2.2;
 
         // set gamma correction
-        if (setjmp(png->jmpbuf))
+        if (setjmp(png_jmpbuf(png)))
             vigra_postcondition( false, png_error_message.insert(0, "error in png_set_gamma(): ").c_str() );
         png_set_gamma( png, screen_gamma, image_gamma );
 #endif
 
         // interlace handling, get number of read passes needed
-        if (setjmp(png->jmpbuf))
+        if (setjmp(png_jmpbuf(png)))
             vigra_postcondition( false,png_error_message.insert(0, "error in png_set_interlace_handling(): ").c_str());
         n_interlace_passes = png_set_interlace_handling(png);
 
         // update png library state to reflect any changes that were made
-        if (setjmp(png->jmpbuf))
+        if (setjmp(png_jmpbuf(png)))
             vigra_postcondition( false, png_error_message.insert(0, "error in png_read_update_info(): ").c_str() );
         png_read_update_info( png, info );
 
-        if (setjmp(png->jmpbuf))
+        if (setjmp(png_jmpbuf(png)))
             vigra_postcondition( false,png_error_message.insert(0, "error in png_get_channels(): ").c_str());
         n_channels = png_get_channels(png, info);
 
-        if (setjmp(png->jmpbuf))
+        if (setjmp(png_jmpbuf(png)))
             vigra_postcondition( false,png_error_message.insert(0, "error in png_get_rowbytes(): ").c_str());
         rowsize = png_get_rowbytes(png, info);
 
@@ -378,9 +392,10 @@
 
     void PngDecoderImpl::nextScanline()
     {
-        for (int i=0; i < n_interlace_passes; i++) {
-        if (setjmp(png->jmpbuf))
-                vigra_postcondition( false,png_error_message.insert(0, "error in png_read_row(): ").c_str());
+        if (setjmp(png_jmpbuf(png)))
+            vigra_postcondition( false,png_error_message.insert(0, "error in png_read_row(): ").c_str());        
+        for (int i=0; i < n_interlace_passes; i++) 
+        {
             png_read_row(png, row_data.begin(), NULL);
         }
     }
@@ -545,7 +560,7 @@
         vigra_postcondition( png != 0, "could not create the write struct." );
 
         // create info struct
-        if (setjmp(png->jmpbuf)) {
+        if (setjmp(png_jmpbuf(png))) {
             png_destroy_write_struct( &png, &info );
             vigra_postcondition( false, png_error_message.insert(0, "error in png_info_struct(): ").c_str() );
         }
@@ -556,7 +571,7 @@
         }
 
         // init png i/o
-        if (setjmp(png->jmpbuf)) {
+        if (setjmp(png_jmpbuf(png))) {
             png_destroy_write_struct( &png, &info );
             vigra_postcondition( false, png_error_message.insert(0, "error in png_init_io(): ").c_str() );
         }
@@ -571,7 +586,7 @@
     void PngEncoderImpl::finalize()
     {
         // write the IHDR
-        if (setjmp(png->jmpbuf))
+        if (setjmp(png_jmpbuf(png)))
             vigra_postcondition( false, png_error_message.insert(0, "error in png_set_IHDR(): ").c_str() );
         png_set_IHDR( png, info, width, height, bit_depth, color_type,
                       PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
@@ -579,7 +594,7 @@
 
         // set resolution
         if (x_resolution > 0 && y_resolution > 0) {
-            if (setjmp(png->jmpbuf))
+            if (setjmp(png_jmpbuf(png)))
                 vigra_postcondition( false, png_error_message.insert(0, "error in png_set_pHYs(): ").c_str() );
             png_set_pHYs(png, info, (png_uint_32) (x_resolution / 0.0254 + 0.5),
                          (png_uint_32) (y_resolution / 0.0254 + 0.5),
@@ -588,7 +603,7 @@
 
         // set offset
         if (position.x > 0 && position.y > 0) {
-            if (setjmp(png->jmpbuf))
+            if (setjmp(png_jmpbuf(png)))
                 vigra_postcondition( false, png_error_message.insert(0, "error in png_set_oFFs(): ").c_str() );
             png_set_oFFs(png, info, position.x, position.y, PNG_OFFSET_PIXEL);
         }
@@ -596,13 +611,17 @@
 #if (PNG_LIBPNG_VER > 10008) && defined(PNG_WRITE_iCCP_SUPPORTED)
         // set icc profile
         if (iccProfile.size() > 0) {
-            png_set_iCCP(png, info, "icc", 0,
-                         (char *)iccProfile.begin(), iccProfile.size());
+            png_set_iCCP(png, info, (png_charp)("icc"), 0,
+#if (PNG_LIBPNG_VER < 10500)
+                         (png_charp)iccProfile.begin(), (png_uint_32)iccProfile.size());
+#else
+                         (png_byte*)iccProfile.begin(), (png_uint_32)iccProfile.size());
+#endif
         }
 #endif
 
         // write the info struct
-        if (setjmp(png->jmpbuf))
+        if (setjmp(png_jmpbuf(png)))
             vigra_postcondition( false, png_error_message.insert(0, "error in png_write_info(): ").c_str() );
         png_write_info( png, info );
 
@@ -634,10 +653,10 @@
         }
 
         // write the whole image
-        if (setjmp(png->jmpbuf))
+        if (setjmp(png_jmpbuf(png)))
             vigra_postcondition( false, png_error_message.insert(0, "error in png_write_image(): ").c_str() );
         png_write_image( png, row_pointers.begin() );
-        if (setjmp(png->jmpbuf))
+        if (setjmp(png_jmpbuf(png)))
             vigra_postcondition( false, png_error_message.insert(0, "error in png_write_end(): ").c_str() );
         png_write_end(png, info);
     }