Revert "libpng 1.6.3"

third_party/libpng/pngerror.c

 
 /* pngerror.c - stub functions for i/o and memory allocation
  *
- * Last changed in libpng 1.6.1 [March 28, 2013]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.2.45 [July 7, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
  *
  * This file provides a location for all error handling.  Users who
  * need special error handling are expected to write replacement functions
  * and use png_set_error_fn() to use those functions.  See the instructions
  * at each function.
  */
 
-#include "pngpriv.h"
-
+#define PNG_INTERNAL
+#define PNG_NO_PEDANTIC_WARNINGS
+#include "png.h"
 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
 
-static PNG_FUNCTION(void, png_default_error,PNGARG((png_const_structrp png_ptr,
-    png_const_charp error_message)),PNG_NORETURN);
-
+static void /* PRIVATE */
+png_default_error PNGARG((png_structp png_ptr,
+  png_const_charp error_message)) PNG_NORETURN;
 #ifdef PNG_WARNINGS_SUPPORTED
 static void /* PRIVATE */
-png_default_warning PNGARG((png_const_structrp png_ptr,
-   png_const_charp warning_message));
+png_default_warning PNGARG((png_structp png_ptr,
+  png_const_charp warning_message));
 #endif /* PNG_WARNINGS_SUPPORTED */
 
 /* This function is called whenever there is a fatal error.  This function
  * should not be changed.  If there is a need to handle errors differently,
  * you should supply a replacement error function and use png_set_error_fn()
  * to replace the error function at run-time.
  */
 #ifdef PNG_ERROR_TEXT_SUPPORTED
-PNG_FUNCTION(void,PNGAPI
-png_error,(png_const_structrp png_ptr, png_const_charp error_message),
-   PNG_NORETURN)
+void PNGAPI
+png_error(png_structp png_ptr, png_const_charp error_message)
 {
 #ifdef PNG_ERROR_NUMBERS_SUPPORTED
    char msg[16];
    if (png_ptr != NULL)
    {
-      if (png_ptr->flags&
-         (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
-      {
-         if (*error_message == PNG_LITERAL_SHARP)
-         {
-            /* Strip "#nnnn " from beginning of error message. */
-            int offset;
-            for (offset = 1; offset<15; offset++)
-               if (error_message[offset] == ' ')
+     if (png_ptr->flags&
+       (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
+     {
+       if (*error_message == PNG_LITERAL_SHARP)
+       {
+           /* Strip "#nnnn " from beginning of error message. */
+           int offset;
+           for (offset = 1; offset<15; offset++)
+              if (error_message[offset] == ' ')
                   break;
-
-            if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
-            {
-               int i;
-               for (i = 0; i < offset - 1; i++)
-                  msg[i] = error_message[i + 1];
-               msg[i - 1] = '\0';
-               error_message = msg;
-            }
-
-            else
-               error_message += offset;
-      }
-
-      else
-      {
-         if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
-         {
-            msg[0] = '0';
-            msg[1] = '\0';
-            error_message = msg;
-         }
+           if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
+           {
+              int i;
+              for (i = 0; i < offset - 1; i++)
+                 msg[i] = error_message[i + 1];
+              msg[i - 1] = '\0';
+              error_message = msg;
+           }
+           else
+              error_message += offset;
+       }
+       else
+       {
+           if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
+           {
+              msg[0] = '0';
+              msg[1] = '\0';
+              error_message = msg;
+           }
        }
      }
    }
 #endif
    if (png_ptr != NULL && png_ptr->error_fn != NULL)
-      (*(png_ptr->error_fn))(png_constcast(png_structrp,png_ptr),
-          error_message);
+      (*(png_ptr->error_fn))(png_ptr, error_message);
 
    /* If the custom handler doesn't exist, or if it returns,
       use the default handler, which will not return. */
    png_default_error(png_ptr, error_message);
 }
 #else
-PNG_FUNCTION(void,PNGAPI
-png_err,(png_const_structrp png_ptr),PNG_NORETURN)
+void PNGAPI
+png_err(png_structp png_ptr)
 {
-   /* Prior to 1.5.2 the error_fn received a NULL pointer, expressed
+   /* Prior to 1.2.45 the error_fn received a NULL pointer, expressed
     * erroneously as '\0', instead of the empty string "".  This was
     * apparently an error, introduced in libpng-1.2.20, and png_default_error
     * will crash in this case.
     */
    if (png_ptr != NULL && png_ptr->error_fn != NULL)
-      (*(png_ptr->error_fn))(png_constcast(png_structrp,png_ptr), "");
+      (*(png_ptr->error_fn))(png_ptr, "");
 
    /* If the custom handler doesn't exist, or if it returns,
       use the default handler, which will not return. */
    png_default_error(png_ptr, "");
 }
 #endif /* PNG_ERROR_TEXT_SUPPORTED */
 
-/* Utility to safely appends strings to a buffer.  This never errors out so
- * error checking is not required in the caller.
- */
-size_t
-png_safecat(png_charp buffer, size_t bufsize, size_t pos,
-   png_const_charp string)
-{
-   if (buffer != NULL && pos < bufsize)
-   {
-      if (string != NULL)
-         while (*string != '\0' && pos < bufsize-1)
-           buffer[pos++] = *string++;
-
-      buffer[pos] = '\0';
-   }
-
-   return pos;
-}
-
-#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
-/* Utility to dump an unsigned value into a buffer, given a start pointer and
- * and end pointer (which should point just *beyond* the end of the buffer!)
- * Returns the pointer to the start of the formatted string.
- */
-png_charp
-png_format_number(png_const_charp start, png_charp end, int format,
-   png_alloc_size_t number)
-{
-   int count = 0;    /* number of digits output */
-   int mincount = 1; /* minimum number required */
-   int output = 0;   /* digit output (for the fixed point format) */
-
-   *--end = '\0';
-
-   /* This is written so that the loop always runs at least once, even with
-    * number zero.
-    */
-   while (end > start && (number != 0 || count < mincount))
-   {
-
-      static const char digits[] = "0123456789ABCDEF";
-
-      switch (format)
-      {
-         case PNG_NUMBER_FORMAT_fixed:
-            /* Needs five digits (the fraction) */
-            mincount = 5;
-            if (output || number % 10 != 0)
-            {
-               *--end = digits[number % 10];
-               output = 1;
-            }
-            number /= 10;
-            break;
-
-         case PNG_NUMBER_FORMAT_02u:
-            /* Expects at least 2 digits. */
-            mincount = 2;
-            /* FALL THROUGH */
-
-         case PNG_NUMBER_FORMAT_u:
-            *--end = digits[number % 10];
-            number /= 10;
-            break;
-
-         case PNG_NUMBER_FORMAT_02x:
-            /* This format expects at least two digits */
-            mincount = 2;
-            /* FALL THROUGH */
-
-         case PNG_NUMBER_FORMAT_x:
-            *--end = digits[number & 0xf];
-            number >>= 4;
-            break;
-
-         default: /* an error */
-            number = 0;
-            break;
-      }
-
-      /* Keep track of the number of digits added */
-      ++count;
-
-      /* Float a fixed number here: */
-      if (format == PNG_NUMBER_FORMAT_fixed) if (count == 5) if (end > start)
-      {
-         /* End of the fraction, but maybe nothing was output?  In that case
-          * drop the decimal point.  If the number is a true zero handle that
-          * here.
-          */
-         if (output)
-            *--end = '.';
-         else if (number == 0) /* and !output */
-            *--end = '0';
-      }
-   }
-
-   return end;
-}
-#endif
-
 #ifdef PNG_WARNINGS_SUPPORTED
 /* This function is called whenever there is a non-fatal error.  This function
  * should not be changed.  If there is a need to handle warnings differently,
  * you should supply a replacement warning function and use
  * png_set_error_fn() to replace the warning function at run-time.
  */
 void PNGAPI
-png_warning(png_const_structrp png_ptr, png_const_charp warning_message)
+png_warning(png_structp png_ptr, png_const_charp warning_message)
 {
    int offset = 0;
    if (png_ptr != NULL)
    {
 #ifdef PNG_ERROR_NUMBERS_SUPPORTED
    if (png_ptr->flags&
-       (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
+     (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
 #endif
-      {
-         if (*warning_message == PNG_LITERAL_SHARP)
-         {
-            for (offset = 1; offset < 15; offset++)
-               if (warning_message[offset] == ' ')
+     {
+       if (*warning_message == PNG_LITERAL_SHARP)
+       {
+           for (offset = 1; offset < 15; offset++)
+              if (warning_message[offset] == ' ')
                   break;
-         }
-      }
+       }
+     }
    }
    if (png_ptr != NULL && png_ptr->warning_fn != NULL)
-      (*(png_ptr->warning_fn))(png_constcast(png_structrp,png_ptr),
-         warning_message + offset);
+      (*(png_ptr->warning_fn))(png_ptr, warning_message + offset);
    else
       png_default_warning(png_ptr, warning_message + offset);
 }
-
-/* These functions support 'formatted' warning messages with up to
- * PNG_WARNING_PARAMETER_COUNT parameters.  In the format string the parameter
- * is introduced by @<number>, where 'number' starts at 1.  This follows the
- * standard established by X/Open for internationalizable error messages.
- */
-void
-png_warning_parameter(png_warning_parameters p, int number,
-   png_const_charp string)
-{
-   if (number > 0 && number <= PNG_WARNING_PARAMETER_COUNT)
-      (void)png_safecat(p[number-1], (sizeof p[number-1]), 0, string);
-}
-
-void
-png_warning_parameter_unsigned(png_warning_parameters p, int number, int format,
-   png_alloc_size_t value)
-{
-   char buffer[PNG_NUMBER_BUFFER_SIZE];
-   png_warning_parameter(p, number, PNG_FORMAT_NUMBER(buffer, format, value));
-}
-
-void
-png_warning_parameter_signed(png_warning_parameters p, int number, int format,
-   png_int_32 value)
-{
-   png_alloc_size_t u;
-   png_charp str;
-   char buffer[PNG_NUMBER_BUFFER_SIZE];
-
-   /* Avoid overflow by doing the negate in a png_alloc_size_t: */
-   u = (png_alloc_size_t)value;
-   if (value < 0)
-      u = ~u + 1;
-
-   str = PNG_FORMAT_NUMBER(buffer, format, u);
-
-   if (value < 0 && str > buffer)
-      *--str = '-';
-
-   png_warning_parameter(p, number, str);
-}
-
-void
-png_formatted_warning(png_const_structrp png_ptr, png_warning_parameters p,
-   png_const_charp message)
-{
-   /* The internal buffer is just 192 bytes - enough for all our messages,
-    * overflow doesn't happen because this code checks!  If someone figures
-    * out how to send us a message longer than 192 bytes, all that will
-    * happen is that the message will be truncated appropriately.
-    */
-   size_t i = 0; /* Index in the msg[] buffer: */
-   char msg[192];
-
-   /* Each iteration through the following loop writes at most one character
-    * to msg[i++] then returns here to validate that there is still space for
-    * the trailing '\0'.  It may (in the case of a parameter) read more than
-    * one character from message[]; it must check for '\0' and continue to the
-    * test if it finds the end of string.
-    */
-   while (i<(sizeof msg)-1 && *message != '\0')
-   {
-      /* '@' at end of string is now just printed (previously it was skipped);
-       * it is an error in the calling code to terminate the string with @.
-       */
-      if (p != NULL && *message == '@' && message[1] != '\0')
-      {
-         int parameter_char = *++message; /* Consume the '@' */
-         static const char valid_parameters[] = "123456789";
-         int parameter = 0;
-
-         /* Search for the parameter digit, the index in the string is the
-          * parameter to use.
-          */
-         while (valid_parameters[parameter] != parameter_char &&
-            valid_parameters[parameter] != '\0')
-            ++parameter;
-
-         /* If the parameter digit is out of range it will just get printed. */
-         if (parameter < PNG_WARNING_PARAMETER_COUNT)
-         {
-            /* Append this parameter */
-            png_const_charp parm = p[parameter];
-            png_const_charp pend = p[parameter] + (sizeof p[parameter]);
-
-            /* No need to copy the trailing '\0' here, but there is no guarantee
-             * that parm[] has been initialized, so there is no guarantee of a
-             * trailing '\0':
-             */
-            while (i<(sizeof msg)-1 && *parm != '\0' && parm < pend)
-               msg[i++] = *parm++;
-
-            /* Consume the parameter digit too: */
-            ++message;
-            continue;
-         }
-
-         /* else not a parameter and there is a character after the @ sign; just
-          * copy that.  This is known not to be '\0' because of the test above.
-          */
-      }
-
-      /* At this point *message can't be '\0', even in the bad parameter case
-       * above where there is a lone '@' at the end of the message string.
-       */
-      msg[i++] = *message++;
-   }
-
-   /* i is always less than (sizeof msg), so: */
-   msg[i] = '\0';
-
-   /* And this is the formatted message. It may be larger than
-    * PNG_MAX_ERROR_TEXT, but that is only used for 'chunk' errors and these
-    * are not (currently) formatted.
-    */
-   png_warning(png_ptr, msg);
-}
 #endif /* PNG_WARNINGS_SUPPORTED */
 
 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
 void PNGAPI
-png_benign_error(png_const_structrp png_ptr, png_const_charp error_message)
+png_benign_error(png_structp png_ptr, png_const_charp error_message)
 {
-   if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN)
-   {
-#     ifdef PNG_READ_SUPPORTED
-         if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 &&
-            png_ptr->chunk_name != 0)
-            png_chunk_warning(png_ptr, error_message);
-         else
-#     endif
-      png_warning(png_ptr, error_message);
-   }
-
-   else
-   {
-#     ifdef PNG_READ_SUPPORTED
-         if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 &&
-            png_ptr->chunk_name != 0)
-            png_chunk_error(png_ptr, error_message);
-         else
-#     endif
-      png_error(png_ptr, error_message);
-   }
+  if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN)
+    png_warning(png_ptr, error_message);
+  else
+    png_error(png_ptr, error_message);
 }
-
-void /* PRIVATE */
-png_app_warning(png_const_structrp png_ptr, png_const_charp error_message)
-{
-  if (png_ptr->flags & PNG_FLAG_APP_WARNINGS_WARN)
-     png_warning(png_ptr, error_message);
-  else
-     png_error(png_ptr, error_message);
-}
-
-void /* PRIVATE */
-png_app_error(png_const_structrp png_ptr, png_const_charp error_message)
-{
-  if (png_ptr->flags & PNG_FLAG_APP_ERRORS_WARN)
-     png_warning(png_ptr, error_message);
-  else
-     png_error(png_ptr, error_message);
-}
-#endif /* BENIGN_ERRORS */
+#endif
 
 /* These utilities are used internally to build an error message that relates
  * to the current chunk.  The chunk name comes from png_ptr->chunk_name,
  * this is used to prefix the message.  The message is limited in length
  * to 63 bytes, the name characters are output as hex digits wrapped in []
  * if the character is invalid.
  */
 #define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97))
 static PNG_CONST char png_digit[16] = {
    '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
    'A', 'B', 'C', 'D', 'E', 'F'
 };
 
-#define PNG_MAX_ERROR_TEXT 196 /* Currently limited be profile_error in png.c */
+#define PNG_MAX_ERROR_TEXT 64
 #if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_ERROR_TEXT_SUPPORTED)
 static void /* PRIVATE */
-png_format_buffer(png_const_structrp png_ptr, png_charp buffer, png_const_charp
-    error_message)
+png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp
+   error_message)
 {
-   png_uint_32 chunk_name = png_ptr->chunk_name;
-   int iout = 0, ishift = 24;
+   int iout = 0, iin = 0;
 
-   while (ishift >= 0)
+   while (iin < 4)
    {
-      int c = (int)(chunk_name >> ishift) & 0xff;
-
-      ishift -= 8;
+      int c = png_ptr->chunk_name[iin++];
       if (isnonalpha(c))
       {
          buffer[iout++] = PNG_LITERAL_LEFT_SQUARE_BRACKET;
          buffer[iout++] = png_digit[(c & 0xf0) >> 4];
          buffer[iout++] = png_digit[c & 0x0f];
          buffer[iout++] = PNG_LITERAL_RIGHT_SQUARE_BRACKET;
       }
-
       else
       {
-         buffer[iout++] = (char)c;
+         buffer[iout++] = (png_byte)c;
       }
    }
 
    if (error_message == NULL)
       buffer[iout] = '\0';
-
    else
    {
-      int iin = 0;
-
       buffer[iout++] = ':';
       buffer[iout++] = ' ';
 
+      iin = 0;
       while (iin < PNG_MAX_ERROR_TEXT-1 && error_message[iin] != '\0')
          buffer[iout++] = error_message[iin++];
 
       /* iin < PNG_MAX_ERROR_TEXT, so the following is safe: */
       buffer[iout] = '\0';
    }
 }
-#endif /* PNG_WARNINGS_SUPPORTED || PNG_ERROR_TEXT_SUPPORTED */
 
-#if defined(PNG_READ_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
-PNG_FUNCTION(void,PNGAPI
-png_chunk_error,(png_const_structrp png_ptr, png_const_charp error_message),
-   PNG_NORETURN)
+#ifdef PNG_READ_SUPPORTED
+void PNGAPI
+png_chunk_error(png_structp png_ptr, png_const_charp error_message)
 {
    char msg[18+PNG_MAX_ERROR_TEXT];
    if (png_ptr == NULL)
-      png_error(png_ptr, error_message);
-
+     png_error(png_ptr, error_message);
    else
    {
-      png_format_buffer(png_ptr, msg, error_message);
-      png_error(png_ptr, msg);
+     png_format_buffer(png_ptr, msg, error_message);
+     png_error(png_ptr, msg);
    }
 }
-#endif /* PNG_READ_SUPPORTED && PNG_ERROR_TEXT_SUPPORTED */
+#endif /* PNG_READ_SUPPORTED */
+#endif /* PNG_WARNINGS_SUPPORTED || PNG_ERROR_TEXT_SUPPORTED */
 
 #ifdef PNG_WARNINGS_SUPPORTED
 void PNGAPI
-png_chunk_warning(png_const_structrp png_ptr, png_const_charp warning_message)
+png_chunk_warning(png_structp png_ptr, png_const_charp warning_message)
 {
    char msg[18+PNG_MAX_ERROR_TEXT];
    if (png_ptr == NULL)
-      png_warning(png_ptr, warning_message);
-
+     png_warning(png_ptr, warning_message);
    else
    {
-      png_format_buffer(png_ptr, msg, warning_message);
-      png_warning(png_ptr, msg);
+     png_format_buffer(png_ptr, msg, warning_message);
+     png_warning(png_ptr, msg);
    }
 }
 #endif /* PNG_WARNINGS_SUPPORTED */
 
 #ifdef PNG_READ_SUPPORTED
 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
 void PNGAPI
-png_chunk_benign_error(png_const_structrp png_ptr, png_const_charp
-    error_message)
+png_chunk_benign_error(png_structp png_ptr, png_const_charp error_message)
 {
-   if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN)
-      png_chunk_warning(png_ptr, error_message);
-
-   else
-      png_chunk_error(png_ptr, error_message);
+  if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN)
+    png_chunk_warning(png_ptr, error_message);
+  else
+    png_chunk_error(png_ptr, error_message);
 }
 #endif
 #endif /* PNG_READ_SUPPORTED */
 
-void /* PRIVATE */
-png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error)
-{
-   /* This is always supported, but for just read or just write it
-    * unconditionally does the right thing.
-    */
-#  if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED)
-      if (png_ptr->mode & PNG_IS_READ_STRUCT)
-#  endif
-
-#  ifdef PNG_READ_SUPPORTED
-      {
-         if (error < PNG_CHUNK_ERROR)
-            png_chunk_warning(png_ptr, message);
-
-         else
-            png_chunk_benign_error(png_ptr, message);
-      }
-#  endif
-
-#  if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED)
-      else if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
-#  endif
-
-#  ifdef PNG_WRITE_SUPPORTED
-      {
-         if (error < PNG_CHUNK_WRITE_ERROR)
-            png_app_warning(png_ptr, message);
-
-         else
-            png_app_error(png_ptr, message);
-      }
-#  endif
-}
-
-#ifdef PNG_ERROR_TEXT_SUPPORTED
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-PNG_FUNCTION(void,
-png_fixed_error,(png_const_structrp png_ptr, png_const_charp name),PNG_NORETURN)
-{
-#  define fixed_message "fixed point overflow in "
-#  define fixed_message_ln ((sizeof fixed_message)-1)
-   int  iin;
-   char msg[fixed_message_ln+PNG_MAX_ERROR_TEXT];
-   memcpy(msg, fixed_message, fixed_message_ln);
-   iin = 0;
-   if (name != NULL) while (iin < (PNG_MAX_ERROR_TEXT-1) && name[iin] != 0)
-   {
-      msg[fixed_message_ln + iin] = name[iin];
-      ++iin;
-   }
-   msg[fixed_message_ln + iin] = 0;
-   png_error(png_ptr, msg);
-}
-#endif
-#endif
-
-#ifdef PNG_SETJMP_SUPPORTED
-/* This API only exists if ANSI-C style error handling is used,
- * otherwise it is necessary for png_default_error to be overridden.
- */
-jmp_buf* PNGAPI
-png_set_longjmp_fn(png_structrp png_ptr, png_longjmp_ptr longjmp_fn,
-    size_t jmp_buf_size)
-{
-   /* From libpng 1.6.0 the app gets one chance to set a 'jmpbuf_size' value
-    * and it must not change after that.  Libpng doesn't care how big the
-    * buffer is, just that it doesn't change.
-    *
-    * If the buffer size is no *larger* than the size of jmp_buf when libpng is
-    * compiled a built in jmp_buf is returned; this preserves the pre-1.6.0
-    * semantics that this call will not fail.  If the size is larger, however,
-    * the buffer is allocated and this may fail, causing the function to return
-    * NULL.
-    */
-   if (png_ptr == NULL)
-      return NULL;
-
-   if (png_ptr->jmp_buf_ptr == NULL)
-   {
-      png_ptr->jmp_buf_size = 0; /* not allocated */
-
-      if (jmp_buf_size <= (sizeof png_ptr->jmp_buf_local))
-         png_ptr->jmp_buf_ptr = &png_ptr->jmp_buf_local;
-
-      else
-      {
-         png_ptr->jmp_buf_ptr = png_voidcast(jmp_buf *,
-            png_malloc_warn(png_ptr, jmp_buf_size));
-
-         if (png_ptr->jmp_buf_ptr == NULL)
-            return NULL; /* new NULL return on OOM */
-
-         png_ptr->jmp_buf_size = jmp_buf_size;
-      }
-   }
-
-   else /* Already allocated: check the size */
-   {
-      size_t size = png_ptr->jmp_buf_size;
-
-      if (size == 0)
-      {
-         size = (sizeof png_ptr->jmp_buf_local);
-         if (png_ptr->jmp_buf_ptr != &png_ptr->jmp_buf_local)
-         {
-            /* This is an internal error in libpng: somehow we have been left
-             * with a stack allocated jmp_buf when the application regained
-             * control.  It's always possible to fix this up, but for the moment
-             * this is a png_error because that makes it easy to detect.
-             */
-            png_error(png_ptr, "Libpng jmp_buf still allocated");
-            /* png_ptr->jmp_buf_ptr = &png_ptr->jmp_buf_local; */
-         }
-      }
-
-      if (size != jmp_buf_size)
-      {
-         png_warning(png_ptr, "Application jmp_buf size changed");
-         return NULL; /* caller will probably crash: no choice here */
-      }
-   }
-
-   /* Finally fill in the function, now we have a satisfactory buffer. It is
-    * valid to change the function on every call.
-    */
-   png_ptr->longjmp_fn = longjmp_fn;
-   return png_ptr->jmp_buf_ptr;
-}
-
-void /* PRIVATE */
-png_free_jmpbuf(png_structrp png_ptr)
-{
-   if (png_ptr != NULL)
-   {
-      jmp_buf *jb = png_ptr->jmp_buf_ptr;
-
-      /* A size of 0 is used to indicate a local, stack, allocation of the
-       * pointer; used here and in png.c
-       */
-      if (jb != NULL && png_ptr->jmp_buf_size > 0)
-      {
-
-         /* This stuff is so that a failure to free the error control structure
-          * does not leave libpng in a state with no valid error handling: the
-          * free always succeeds, if there is an error it gets ignored.
-          */
-         if (jb != &png_ptr->jmp_buf_local)
-         {
-            /* Make an internal, libpng, jmp_buf to return here */
-            jmp_buf free_jmp_buf;
-
-            if (!setjmp(free_jmp_buf))
-            {
-               png_ptr->jmp_buf_ptr = &free_jmp_buf; /* come back here */
-               png_ptr->jmp_buf_size = 0; /* stack allocation */
-               png_ptr->longjmp_fn = longjmp;
-               png_free(png_ptr, jb); /* Return to setjmp on error */
-            }
-         }
-      }
-
-      /* *Always* cancel everything out: */
-      png_ptr->jmp_buf_size = 0;
-      png_ptr->jmp_buf_ptr = NULL;
-      png_ptr->longjmp_fn = 0;
-   }
-}
-#endif
-
 /* This is the default error handling function.  Note that replacements for
  * this function MUST NOT RETURN, or the program will likely crash.  This
  * function is used by default, or if the program supplies NULL for the
  * error function pointer in png_set_error_fn().
  */
-static PNG_FUNCTION(void /* PRIVATE */,
-png_default_error,(png_const_structrp png_ptr, png_const_charp error_message),
-   PNG_NORETURN)
+static void /* PRIVATE */
+png_default_error(png_structp png_ptr, png_const_charp error_message)
 {
 #ifdef PNG_CONSOLE_IO_SUPPORTED
 #ifdef PNG_ERROR_NUMBERS_SUPPORTED
-   /* Check on NULL only added in 1.5.4 */
-   if (error_message != NULL && *error_message == PNG_LITERAL_SHARP)
+   if (*error_message == PNG_LITERAL_SHARP)
    {
-      /* Strip "#nnnn " from beginning of error message. */
-      int offset;
-      char error_number[16];
-      for (offset = 0; offset<15; offset++)
-      {
+     /* Strip "#nnnn " from beginning of error message. */
+     int offset;
+     char error_number[16];
+     for (offset = 0; offset<15; offset++)
+     {
          error_number[offset] = error_message[offset + 1];
          if (error_message[offset] == ' ')
-            break;
-      }
-
-      if ((offset > 1) && (offset < 15))
-      {
-         error_number[offset - 1] = '\0';
-         fprintf(stderr, "libpng error no. %s: %s",
-             error_number, error_message + offset + 1);
-         fprintf(stderr, PNG_STRING_NEWLINE);
-      }
-
-      else
-      {
-         fprintf(stderr, "libpng error: %s, offset=%d",
-             error_message, offset);
-         fprintf(stderr, PNG_STRING_NEWLINE);
-      }
+             break;
+     }
+     if ((offset > 1) && (offset < 15))
+     {
+       error_number[offset - 1] = '\0';
+       fprintf(stderr, "libpng error no. %s: %s",
+          error_number, error_message + offset + 1);
+       fprintf(stderr, PNG_STRING_NEWLINE);
+     }
+     else
+     {
+       fprintf(stderr, "libpng error: %s, offset=%d",
+          error_message, offset);
+       fprintf(stderr, PNG_STRING_NEWLINE);
+     }
    }
    else
 #endif
    {
-      fprintf(stderr, "libpng error: %s", error_message ? error_message :
-         "undefined");
+      fprintf(stderr, "libpng error: %s", error_message);
       fprintf(stderr, PNG_STRING_NEWLINE);
    }
-#else
-   PNG_UNUSED(error_message) /* Make compiler happy */
-#endif
-   png_longjmp(png_ptr, 1);
-}
-
-PNG_FUNCTION(void,PNGAPI
-png_longjmp,(png_const_structrp png_ptr, int val),PNG_NORETURN)
-{
-#ifdef PNG_SETJMP_SUPPORTED
-   if (png_ptr && png_ptr->longjmp_fn && png_ptr->jmp_buf_ptr)
-      png_ptr->longjmp_fn(*png_ptr->jmp_buf_ptr, val);
 #endif
 
+#ifdef PNG_SETJMP_SUPPORTED
+   if (png_ptr)
+   {
+#  ifdef USE_FAR_KEYWORD
+   {
+      jmp_buf jmpbuf;
+      png_memcpy(jmpbuf, png_ptr->jmpbuf, png_sizeof(jmp_buf));
+     longjmp(jmpbuf,1);
+   }
+#  else
+   longjmp(png_ptr->jmpbuf, 1);
+#  endif
+   }
+#endif
    /* Here if not setjmp support or if png_ptr is null. */
    PNG_ABORT();
+#ifndef PNG_CONSOLE_IO_SUPPORTED
+   error_message = error_message; /* Make compiler happy */
+#endif
 }
 
 #ifdef PNG_WARNINGS_SUPPORTED
 /* This function is called when there is a warning, but the library thinks
  * it can continue anyway.  Replacement functions don't have to do anything
  * here if you don't want them to.  In the default configuration, png_ptr is
  * not used, but it is passed in case it may be useful.
  */
 static void /* PRIVATE */
-png_default_warning(png_const_structrp png_ptr, png_const_charp warning_message)
+png_default_warning(png_structp png_ptr, png_const_charp warning_message)
 {
 #ifdef PNG_CONSOLE_IO_SUPPORTED
 #  ifdef PNG_ERROR_NUMBERS_SUPPORTED
    if (*warning_message == PNG_LITERAL_SHARP)
    {
-      int offset;
-      char warning_number[16];
-      for (offset = 0; offset < 15; offset++)
-      {
-         warning_number[offset] = warning_message[offset + 1];
-         if (warning_message[offset] == ' ')
+     int offset;
+     char warning_number[16];
+     for (offset = 0; offset < 15; offset++)
+     {
+        warning_number[offset] = warning_message[offset + 1];
+        if (warning_message[offset] == ' ')
             break;
-      }
-
-      if ((offset > 1) && (offset < 15))
-      {
-         warning_number[offset + 1] = '\0';
-         fprintf(stderr, "libpng warning no. %s: %s",
-             warning_number, warning_message + offset);
-         fprintf(stderr, PNG_STRING_NEWLINE);
-      }
-
-      else
-      {
-         fprintf(stderr, "libpng warning: %s",
-             warning_message);
-         fprintf(stderr, PNG_STRING_NEWLINE);
-      }
+     }
+     if ((offset > 1) && (offset < 15))
+     {
+       warning_number[offset + 1] = '\0';
+       fprintf(stderr, "libpng warning no. %s: %s",
+          warning_number, warning_message + offset);
+       fprintf(stderr, PNG_STRING_NEWLINE);
+     }
+     else
+     {
+       fprintf(stderr, "libpng warning: %s",
+          warning_message);
+       fprintf(stderr, PNG_STRING_NEWLINE);
+     }
    }
    else
 #  endif
-
    {
-      fprintf(stderr, "libpng warning: %s", warning_message);
-      fprintf(stderr, PNG_STRING_NEWLINE);
+     fprintf(stderr, "libpng warning: %s", warning_message);
+     fprintf(stderr, PNG_STRING_NEWLINE);
    }
 #else
-   PNG_UNUSED(warning_message) /* Make compiler happy */
+   warning_message = warning_message; /* Make compiler happy */
 #endif
-   PNG_UNUSED(png_ptr) /* Make compiler happy */
+   png_ptr = png_ptr; /* Make compiler happy */
 }
 #endif /* PNG_WARNINGS_SUPPORTED */
 
 /* This function is called when the application wants to use another method
  * of handling errors and warnings.  Note that the error function MUST NOT
  * return to the calling routine or serious problems will occur.  The return
- * method used in the default routine calls longjmp(png_ptr->jmp_buf_ptr, 1)
+ * method used in the default routine calls longjmp(png_ptr->jmpbuf, 1)
  */
 void PNGAPI
-png_set_error_fn(png_structrp png_ptr, png_voidp error_ptr,
-    png_error_ptr error_fn, png_error_ptr warning_fn)
+png_set_error_fn(png_structp png_ptr, png_voidp error_ptr,
+   png_error_ptr error_fn, png_error_ptr warning_fn)
 {
    if (png_ptr == NULL)
       return;
-
    png_ptr->error_ptr = error_ptr;
    png_ptr->error_fn = error_fn;
-#ifdef PNG_WARNINGS_SUPPORTED
    png_ptr->warning_fn = warning_fn;
-#else
-   PNG_UNUSED(warning_fn)
-#endif
 }
 
 
 /* This function returns a pointer to the error_ptr associated with the user
  * functions.  The application should free any memory associated with this
  * pointer before png_write_destroy and png_read_destroy are called.
  */
 png_voidp PNGAPI
-png_get_error_ptr(png_const_structrp png_ptr)
+png_get_error_ptr(png_structp png_ptr)
 {
    if (png_ptr == NULL)
       return NULL;
-
    return ((png_voidp)png_ptr->error_ptr);
 }
 
 
 #ifdef PNG_ERROR_NUMBERS_SUPPORTED
 void PNGAPI
-png_set_strip_error_numbers(png_structrp png_ptr, png_uint_32 strip_mode)
+png_set_strip_error_numbers(png_structp png_ptr, png_uint_32 strip_mode)
 {
    if (png_ptr != NULL)
    {
-      png_ptr->flags &=
-         ((~(PNG_FLAG_STRIP_ERROR_NUMBERS |
-         PNG_FLAG_STRIP_ERROR_TEXT))&strip_mode);
+     png_ptr->flags &=
+       ((~(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))&strip_mode);
    }
 }
 #endif
-
-#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
-   defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
-   /* Currently the above both depend on SETJMP_SUPPORTED, however it would be
-    * possible to implement without setjmp support just so long as there is some
-    * way to handle the error return here:
-    */
-PNG_FUNCTION(void /* PRIVATE */,
-png_safe_error,(png_structp png_nonconst_ptr, png_const_charp error_message),
-   PNG_NORETURN)
-{
-   const png_const_structrp png_ptr = png_nonconst_ptr;
-   png_imagep image = png_voidcast(png_imagep, png_ptr->error_ptr);
-
-   /* An error is always logged here, overwriting anything (typically a warning)
-    * that is already there:
-    */
-   if (image != NULL)
-   {
-      png_safecat(image->message, (sizeof image->message), 0, error_message);
-      image->warning_or_error |= PNG_IMAGE_ERROR;
-
-      /* Retrieve the jmp_buf from within the png_control, making this work for
-       * C++ compilation too is pretty tricky: C++ wants a pointer to the first
-       * element of a jmp_buf, but C doesn't tell us the type of that.
-       */
-      if (image->opaque != NULL && image->opaque->error_buf != NULL)
-         longjmp(png_control_jmp_buf(image->opaque), 1);
-
-      /* Missing longjmp buffer, the following is to help debugging: */
-      {
-         size_t pos = png_safecat(image->message, (sizeof image->message), 0,
-            "bad longjmp: ");
-         png_safecat(image->message, (sizeof image->message), pos,
-             error_message);
-      }
-   }
-
-   /* Here on an internal programming error. */
-   abort();
-}
-
-#ifdef PNG_WARNINGS_SUPPORTED
-void /* PRIVATE */
-png_safe_warning(png_structp png_nonconst_ptr, png_const_charp warning_message)
-{
-   const png_const_structrp png_ptr = png_nonconst_ptr;
-   png_imagep image = png_voidcast(png_imagep, png_ptr->error_ptr);
-
-   /* A warning is only logged if there is no prior warning or error. */
-   if (image->warning_or_error == 0)
-   {
-      png_safecat(image->message, (sizeof image->message), 0, warning_message);
-      image->warning_or_error |= PNG_IMAGE_WARNING;
-   }
-}
-#endif
-
-int /* PRIVATE */
-png_safe_execute(png_imagep image_in, int (*function)(png_voidp), png_voidp arg)
-{
-   volatile png_imagep image = image_in;
-   volatile int result;
-   volatile png_voidp saved_error_buf;
-   jmp_buf safe_jmpbuf;
-
-   /* Safely execute function(arg) with png_error returning to this function. */
-   saved_error_buf = image->opaque->error_buf;
-   result = setjmp(safe_jmpbuf) == 0;
-
-   if (result)
-   {
-
-      image->opaque->error_buf = safe_jmpbuf;
-      result = function(arg);
-   }
-
-   image->opaque->error_buf = saved_error_buf;
-
-   /* And do the cleanup prior to any failure return. */
-   if (!result)
-      png_image_free(image);
-
-   return result;
-}
-#endif /* SIMPLIFIED READ/WRITE */
 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */