/* pngrio.c - functions for data input
*
- * libpng 1.0.1
+ * libpng 1.2.5rc3 - September 18, 2002
* 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) 1998-2002 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 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(...).
*/
with very small lengths, so you should implement some kind of simple
buffering if you are using unbuffered reads. This should never be asked
to read more then 64K on a 16 bit machine. */
-void
+void /* PRIVATE */
png_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
{
- png_debug1(4,"reading %d bytes\n", length);
+ png_debug1(4,"reading %d bytes\n", (int)length);
if (png_ptr->read_data_fn != NULL)
(*(png_ptr->read_data_fn))(png_ptr, data, length);
else
}
#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. */
#ifndef USE_FAR_KEYWORD
-static void
+void PNGAPI
png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
{
png_size_t check;
/* fread() returns 0 on error, so it is OK to store this in a png_size_t
* instead of an int, which is what fread() actually returns.
*/
+#if defined(_WIN32_WCE)
+ if ( !ReadFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) )
+ check = 0;
+#else
check = (png_size_t)fread(data, (png_size_t)1, length,
- (FILE *)png_ptr->io_ptr);
+ (png_FILE_p)png_ptr->io_ptr);
+#endif
if (check != length)
- {
png_error(png_ptr, "Read Error");
- }
}
#else
/* this is the model-independent version. Since the standard I/O 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
+
+static void /* PRIVATE */
png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
{
int check;
png_byte *n_data;
- FILE *io_ptr;
+ png_FILE_p io_ptr;
/* Check if data really is near. If so, use usual code. */
n_data = (png_byte *)CVT_PTR_NOCHECK(data);
- io_ptr = (FILE *)CVT_PTR(png_ptr->io_ptr);
+ io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr);
if ((png_bytep)n_data == data)
{
+#if defined(_WIN32_WCE)
+ if ( !ReadFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) )
+ check = 0;
+#else
check = fread(n_data, 1, length, io_ptr);
+#endif
}
else
{
do
{
read = MIN(NEAR_BUF_SIZE, remaining);
+#if defined(_WIN32_WCE)
+ if ( !ReadFile((HANDLE)(io_ptr), buf, read, &err, NULL) )
+ err = 0;
+#else
err = fread(buf, (png_size_t)1, read, io_ptr);
+#endif
png_memcpy(data, buf, read); /* copy far buffer to near buffer */
if(err != read)
break;
while (remaining != 0);
}
if ((png_uint_32)check != (png_uint_32)length)
- {
png_error(png_ptr, "read Error");
- }
}
#endif
#endif
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
+void PNGAPI
png_set_read_fn(png_structp png_ptr, png_voidp io_ptr,
png_rw_ptr read_data_fn)
{
#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;
-#endif /* PNG_WRITE_FLUSH_SUPPORTED */
+#endif
}
-