1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libpng/pngwio.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,168 @@
1.4 +
1.5 +/* pngwio.c - functions for data output
1.6 + *
1.7 + * Last changed in libpng 1.6.9 [February 6, 2014]
1.8 + * Copyright (c) 1998-2014 Glenn Randers-Pehrson
1.9 + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
1.10 + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
1.11 + *
1.12 + * This code is released under the libpng license.
1.13 + * For conditions of distribution and use, see the disclaimer
1.14 + * and license in png.h
1.15 + *
1.16 + * This file provides a location for all output. Users who need
1.17 + * special handling are expected to write functions that have the same
1.18 + * arguments as these and perform similar functions, but that possibly
1.19 + * use different output methods. Note that you shouldn't change these
1.20 + * functions, but rather write replacement functions and then change
1.21 + * them at run time with png_set_write_fn(...).
1.22 + */
1.23 +
1.24 +#include "pngpriv.h"
1.25 +
1.26 +#ifdef PNG_WRITE_SUPPORTED
1.27 +
1.28 +/* Write the data to whatever output you are using. The default routine
1.29 + * writes to a file pointer. Note that this routine sometimes gets called
1.30 + * with very small lengths, so you should implement some kind of simple
1.31 + * buffering if you are using unbuffered writes. This should never be asked
1.32 + * to write more than 64K on a 16 bit machine.
1.33 + */
1.34 +
1.35 +void /* PRIVATE */
1.36 +png_write_data(png_structrp png_ptr, png_const_bytep data, png_size_t length)
1.37 +{
1.38 + /* NOTE: write_data_fn must not change the buffer! */
1.39 + if (png_ptr->write_data_fn != NULL )
1.40 + (*(png_ptr->write_data_fn))(png_ptr, png_constcast(png_bytep,data),
1.41 + length);
1.42 +
1.43 + else
1.44 + png_error(png_ptr, "Call to NULL write function");
1.45 +}
1.46 +
1.47 +#ifdef PNG_STDIO_SUPPORTED
1.48 +/* This is the function that does the actual writing of data. If you are
1.49 + * not writing to a standard C stream, you should create a replacement
1.50 + * write_data function and use it at run time with png_set_write_fn(), rather
1.51 + * than changing the library.
1.52 + */
1.53 +void PNGCBAPI
1.54 +png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
1.55 +{
1.56 + png_size_t check;
1.57 +
1.58 + if (png_ptr == NULL)
1.59 + return;
1.60 +
1.61 + check = fwrite(data, 1, length, (png_FILE_p)(png_ptr->io_ptr));
1.62 +
1.63 + if (check != length)
1.64 + png_error(png_ptr, "Write Error");
1.65 +}
1.66 +#endif
1.67 +
1.68 +/* This function is called to output any data pending writing (normally
1.69 + * to disk). After png_flush is called, there should be no data pending
1.70 + * writing in any buffers.
1.71 + */
1.72 +#ifdef PNG_WRITE_FLUSH_SUPPORTED
1.73 +void /* PRIVATE */
1.74 +png_flush(png_structrp png_ptr)
1.75 +{
1.76 + if (png_ptr->output_flush_fn != NULL)
1.77 + (*(png_ptr->output_flush_fn))(png_ptr);
1.78 +}
1.79 +
1.80 +# ifdef PNG_STDIO_SUPPORTED
1.81 +void PNGCBAPI
1.82 +png_default_flush(png_structp png_ptr)
1.83 +{
1.84 + png_FILE_p io_ptr;
1.85 +
1.86 + if (png_ptr == NULL)
1.87 + return;
1.88 +
1.89 + io_ptr = png_voidcast(png_FILE_p, (png_ptr->io_ptr));
1.90 + fflush(io_ptr);
1.91 +}
1.92 +# endif
1.93 +#endif
1.94 +
1.95 +/* This function allows the application to supply new output functions for
1.96 + * libpng if standard C streams aren't being used.
1.97 + *
1.98 + * This function takes as its arguments:
1.99 + * png_ptr - pointer to a png output data structure
1.100 + * io_ptr - pointer to user supplied structure containing info about
1.101 + * the output functions. May be NULL.
1.102 + * write_data_fn - pointer to a new output function that takes as its
1.103 + * arguments a pointer to a png_struct, a pointer to
1.104 + * data to be written, and a 32-bit unsigned int that is
1.105 + * the number of bytes to be written. The new write
1.106 + * function should call png_error(png_ptr, "Error msg")
1.107 + * to exit and output any fatal error messages. May be
1.108 + * NULL, in which case libpng's default function will
1.109 + * be used.
1.110 + * flush_data_fn - pointer to a new flush function that takes as its
1.111 + * arguments a pointer to a png_struct. After a call to
1.112 + * the flush function, there should be no data in any buffers
1.113 + * or pending transmission. If the output method doesn't do
1.114 + * any buffering of output, a function prototype must still be
1.115 + * supplied although it doesn't have to do anything. If
1.116 + * PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile
1.117 + * time, output_flush_fn will be ignored, although it must be
1.118 + * supplied for compatibility. May be NULL, in which case
1.119 + * libpng's default function will be used, if
1.120 + * PNG_WRITE_FLUSH_SUPPORTED is defined. This is not
1.121 + * a good idea if io_ptr does not point to a standard
1.122 + * *FILE structure.
1.123 + */
1.124 +void PNGAPI
1.125 +png_set_write_fn(png_structrp png_ptr, png_voidp io_ptr,
1.126 + png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)
1.127 +{
1.128 + if (png_ptr == NULL)
1.129 + return;
1.130 +
1.131 + png_ptr->io_ptr = io_ptr;
1.132 +
1.133 +#ifdef PNG_STDIO_SUPPORTED
1.134 + if (write_data_fn != NULL)
1.135 + png_ptr->write_data_fn = write_data_fn;
1.136 +
1.137 + else
1.138 + png_ptr->write_data_fn = png_default_write_data;
1.139 +#else
1.140 + png_ptr->write_data_fn = write_data_fn;
1.141 +#endif
1.142 +
1.143 +#ifdef PNG_WRITE_FLUSH_SUPPORTED
1.144 +# ifdef PNG_STDIO_SUPPORTED
1.145 +
1.146 + if (output_flush_fn != NULL)
1.147 + png_ptr->output_flush_fn = output_flush_fn;
1.148 +
1.149 + else
1.150 + png_ptr->output_flush_fn = png_default_flush;
1.151 +
1.152 +# else
1.153 + png_ptr->output_flush_fn = output_flush_fn;
1.154 +# endif
1.155 +#else
1.156 + PNG_UNUSED(output_flush_fn)
1.157 +#endif /* PNG_WRITE_FLUSH_SUPPORTED */
1.158 +
1.159 +#ifdef PNG_READ_SUPPORTED
1.160 + /* It is an error to read while writing a png file */
1.161 + if (png_ptr->read_data_fn != NULL)
1.162 + {
1.163 + png_ptr->read_data_fn = NULL;
1.164 +
1.165 + png_warning(png_ptr,
1.166 + "Can't set both read_data_fn and write_data_fn in the"
1.167 + " same structure");
1.168 + }
1.169 +#endif
1.170 +}
1.171 +#endif /* PNG_WRITE_SUPPORTED */
