Imported from libpng-1.0.5.tar
diff --git a/png.c b/png.c
index acd2974..44310c7 100644
--- a/png.c
+++ b/png.c
@@ -1,7 +1,7 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * libpng version 1.0.5 - October 5, 1999
+ * libpng version 1.0.5 - October 15, 1999
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
@@ -12,6 +12,8 @@
 #define PNG_NO_EXTERN
 #include "png.h"
 
+PNG_GET_HEADER
+
 /* Version information for C files.  This had better match the version
  * string defined in png.h.
  */
@@ -86,7 +88,7 @@
    if (num_bytes > 8)
       png_error(png_ptr, "Too many bytes for PNG signature.");
 
-   png_ptr->sig_bytes = num_bytes < 0 ? 0 : num_bytes;
+   png_ptr->sig_bytes = (png_byte)(num_bytes < 0 ? 0 : num_bytes);
 }
 
 /* Checks whether the supplied bytes match the PNG signature.  We allow
@@ -350,12 +352,12 @@
 png_charp
 png_get_copyright(png_structp png_ptr)
 {
-   if(png_ptr == NULL)
-     /* silence compiler warning about unused png_ptr */ ;
-   return("\n libpng version 1.0.5 - October 5, 1999\n\
+   if (png_ptr != NULL || png_ptr == NULL)  /* silence compiler warning */
+   return ("\n libpng version 1.0.5 - October 15, 1999\n\
    Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.\n\
    Copyright (c) 1996, 1997 Andreas Dilger\n\
    Copyright (c) 1998, 1999 Glenn Randers-Pehrson\n");
+   return ("");
 }
 
 /* Generate a compiler error if there is an old png.h in the search path. */
@@ -364,5 +366,5 @@
    (version_1_0_5 png_h_is_not_version_1_0_5)
 {
    if(png_h_is_not_version_1_0_5 == NULL)
-     /* silence compiler warning about unused parameter */ ;
+     return;
 }