/* pngrio.c - functions for data input
*
- * libpng 1.0.1
+ * libpng 1.0.3 - January 14, 1999
* For conditions of distribution and use, see copyright notice in png.h
* Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
* Copyright (c) 1996, 1997 Andreas Dilger
- * Copyright (c) 1998, Glenn Randers-Pehrson
- * March 15, 1998
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
*
- * This file provides a location for all input. Users which need
- * special handling are expected to write a function which has the same
- * arguments as this, and perform a similar function, but possibly has
- * a different input method. Note that you shouldn't change this
+ * This file provides a location for all input. Users who need
+ * special handling are expected to write a function that has the same
+ * arguments as this and performs a similar function, but that possibly
+ * has a different input method. Note that you shouldn't change this
* function, but rather write a replacement function and then make
* libpng use it at run time with png_set_read_fn(...).
*/
#define PNG_INTERNAL
-#include "../png/png.h"
+#include "png.h"
/* Read the data from whatever input you are using. The default routine
reads from a file pointer. Note that this routine sometimes gets called
}
#if !defined(PNG_NO_STDIO)
-/* This is the function which does the actual reading of data. If you are
+/* This is the function that does the actual reading of data. If you are
not reading from a standard C stream, you should create a replacement
read_data function and use it at run time with png_set_read_fn(), rather
than changing the library. */
can't handle far buffers in the medium and small models, we have to copy
the data.
*/
-
+
#define NEAR_BUF_SIZE 1024
#define MIN(a,b) (a <= b ? a : b)
-
+
static void
png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
{
png_ptr - pointer to a png input data structure
io_ptr - pointer to user supplied structure containing info about
the input functions. May be NULL.
- read_data_fn - pointer to a new input function which takes as it's
+ read_data_fn - pointer to a new input function that takes as its
arguments a pointer to a png_struct, a pointer to
a location where input data can be stored, and a 32-bit
- unsigned int which is the number of bytes to be read.
+ unsigned int that is the number of bytes to be read.
To exit and output any fatal error messages the new write
function should call png_error(png_ptr, "Error msg"). */
void
#endif
/* It is an error to write to a read device */
- png_ptr->write_data_fn = NULL;
+ if (png_ptr->write_data_fn != NULL)
+ {
+ png_ptr->write_data_fn = NULL;
+ png_warning(png_ptr,
+ "It's an error to set both read_data_fn and write_data_fn in the ");
+ png_warning(png_ptr,
+ "same structure. Resetting write_data_fn to NULL.");
+ }
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
png_ptr->output_flush_fn = NULL;