libpng 1.6.3

third_party/libpng/pngwio.c

 
 /* pngwio.c - functions for data output
  *
- * Last changed in libpng 1.2.41 [December 3, 2009]
- * Copyright (c) 1998-2009 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.0 [February 14, 2013]
+ * Copyright (c) 1998-2013 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 output.  Users who need
  * special handling are expected to write functions that have the same
  * arguments as these and perform similar functions, but that possibly
  * use different output methods.  Note that you shouldn't change these
  * functions, but rather write replacement functions and then change
  * them at run time with png_set_write_fn(...).
  */
 
-#define PNG_INTERNAL
-#define PNG_NO_PEDANTIC_WARNINGS
-#include "png.h"
+#include "pngpriv.h"
+
 #ifdef PNG_WRITE_SUPPORTED
 
 /* Write the data to whatever output you are using.  The default routine
  * writes to a file pointer.  Note that this routine sometimes gets called
  * with very small lengths, so you should implement some kind of simple
  * buffering if you are using unbuffered writes.  This should never be asked
  * to write more than 64K on a 16 bit machine.
  */
 
 void /* PRIVATE */
-png_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+png_write_data(png_structrp png_ptr, png_const_bytep data, png_size_t length)
 {
+   /* NOTE: write_data_fn must not change the buffer! */
    if (png_ptr->write_data_fn != NULL )
-      (*(png_ptr->write_data_fn))(png_ptr, data, length);
+      (*(png_ptr->write_data_fn))(png_ptr, png_constcast(png_bytep,data),
+         length);
+
    else
       png_error(png_ptr, "Call to NULL write function");
 }
 
 #ifdef PNG_STDIO_SUPPORTED
 /* This is the function that does the actual writing of data.  If you are
  * not writing to a standard C stream, you should create a replacement
  * write_data function and use it at run time with png_set_write_fn(), rather
  * than changing the library.
  */
-#ifndef USE_FAR_KEYWORD
-void PNGAPI
+void PNGCBAPI
 png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
-   png_uint_32 check;
+   png_size_t check;
 
    if (png_ptr == NULL)
       return;
-#ifdef _WIN32_WCE
-   if ( !WriteFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) )
-      check = 0;
-#else
+
    check = fwrite(data, 1, length, (png_FILE_p)(png_ptr->io_ptr));
-#endif
+
    if (check != length)
       png_error(png_ptr, "Write 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)
-
-void PNGAPI
-png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
-{
-   png_uint_32 check;
-   png_byte *near_data;  /* Needs to be "png_byte *" instead of "png_bytep" */
-   png_FILE_p io_ptr;
-
-   if (png_ptr == NULL)
-      return;
-   /* Check if data really is near. If so, use usual code. */
-   near_data = (png_byte *)CVT_PTR_NOCHECK(data);
-   io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr);
-   if ((png_bytep)near_data == data)
-   {
-#ifdef _WIN32_WCE
-      if ( !WriteFile(io_ptr, near_data, length, &check, NULL) )
-         check = 0;
-#else
-      check = fwrite(near_data, 1, length, io_ptr);
-#endif
-   }
-   else
-   {
-      png_byte buf[NEAR_BUF_SIZE];
-      png_size_t written, remaining, err;
-      check = 0;
-      remaining = length;
-      do
-      {
-         written = MIN(NEAR_BUF_SIZE, remaining);
-         png_memcpy(buf, data, written); /* Copy far buffer to near buffer */
-#ifdef _WIN32_WCE
-         if ( !WriteFile(io_ptr, buf, written, &err, NULL) )
-            err = 0;
-#else
-         err = fwrite(buf, 1, written, io_ptr);
-#endif
-         if (err != written)
-            break;
-
-         else
-            check += err;
-
-         data += written;
-         remaining -= written;
-      }
-      while (remaining != 0);
-   }
-   if (check != length)
-      png_error(png_ptr, "Write Error");
-}
-
-#endif
 #endif
 
 /* This function is called to output any data pending writing (normally
  * to disk).  After png_flush is called, there should be no data pending
  * writing in any buffers.
  */
 #ifdef PNG_WRITE_FLUSH_SUPPORTED
 void /* PRIVATE */
-png_flush(png_structp png_ptr)
+png_flush(png_structrp png_ptr)
 {
    if (png_ptr->output_flush_fn != NULL)
       (*(png_ptr->output_flush_fn))(png_ptr);
 }
 
-#ifdef PNG_STDIO_SUPPORTED
-void PNGAPI
+#  ifdef PNG_STDIO_SUPPORTED
+void PNGCBAPI
 png_default_flush(png_structp png_ptr)
 {
-#ifndef _WIN32_WCE
    png_FILE_p io_ptr;
-#endif
+
    if (png_ptr == NULL)
       return;
-#ifndef _WIN32_WCE
-   io_ptr = (png_FILE_p)CVT_PTR((png_ptr->io_ptr));
+
+   io_ptr = png_voidcast(png_FILE_p, (png_ptr->io_ptr));
    fflush(io_ptr);
-#endif
 }
-#endif
+#  endif
 #endif
 
 /* This function allows the application to supply new output functions for
  * libpng if standard C streams aren't being used.
  *
  * This function takes as its arguments:
  * png_ptr       - pointer to a png output data structure
  * io_ptr        - pointer to user supplied structure containing info about
  *                 the output functions.  May be NULL.
  * write_data_fn - pointer to a new output function that takes as its
@@ skipping 12 matching lines @@
  *                 supplied although it doesn't have to do anything.  If
  *                 PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile
  *                 time, output_flush_fn will be ignored, although it must be
  *                 supplied for compatibility.  May be NULL, in which case
  *                 libpng's default function will be used, if
  *                 PNG_WRITE_FLUSH_SUPPORTED is defined.  This is not
  *                 a good idea if io_ptr does not point to a standard
  *                 *FILE structure.
  */
 void PNGAPI
-png_set_write_fn(png_structp png_ptr, png_voidp io_ptr,
-   png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)
+png_set_write_fn(png_structrp png_ptr, png_voidp io_ptr,
+    png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)
 {
    if (png_ptr == NULL)
       return;
 
    png_ptr->io_ptr = io_ptr;
 
 #ifdef PNG_STDIO_SUPPORTED
    if (write_data_fn != NULL)
       png_ptr->write_data_fn = write_data_fn;
 
    else
       png_ptr->write_data_fn = png_default_write_data;
 #else
    png_ptr->write_data_fn = write_data_fn;
 #endif
 
 #ifdef PNG_WRITE_FLUSH_SUPPORTED
-#ifdef PNG_STDIO_SUPPORTED
+#  ifdef PNG_STDIO_SUPPORTED
+
    if (output_flush_fn != NULL)
       png_ptr->output_flush_fn = output_flush_fn;
 
    else
       png_ptr->output_flush_fn = png_default_flush;
-#else
+
+#  else
    png_ptr->output_flush_fn = output_flush_fn;
-#endif
+#  endif
 #endif /* PNG_WRITE_FLUSH_SUPPORTED */
 
    /* It is an error to read while writing a png file */
    if (png_ptr->read_data_fn != NULL)
    {
       png_ptr->read_data_fn = NULL;
+
       png_warning(png_ptr,
-         "Attempted to set both read_data_fn and write_data_fn in");
-      png_warning(png_ptr,
-         "the same structure.  Resetting read_data_fn to NULL.");
+          "Can't set both read_data_fn and write_data_fn in the"
+          " same structure");
    }
 }
-
-#ifdef USE_FAR_KEYWORD
-#ifdef _MSC_VER
-void *png_far_to_near(png_structp png_ptr, png_voidp ptr, int check)
-{
-   void *near_ptr;
-   void FAR *far_ptr;
-   FP_OFF(near_ptr) = FP_OFF(ptr);
-   far_ptr = (void FAR *)near_ptr;
-
-   if (check != 0)
-      if (FP_SEG(ptr) != FP_SEG(far_ptr))
-         png_error(png_ptr, "segment lost in conversion");
-
-   return(near_ptr);
-}
-#  else
-void *png_far_to_near(png_structp png_ptr, png_voidp ptr, int check)
-{
-   void *near_ptr;
-   void FAR *far_ptr;
-   near_ptr = (void FAR *)ptr;
-   far_ptr = (void FAR *)near_ptr;
-
-   if (check != 0)
-      if (far_ptr != ptr)
-         png_error(png_ptr, "segment lost in conversion");
-
-   return(near_ptr);
-}
-#   endif
-#   endif
 #endif /* PNG_WRITE_SUPPORTED */