Wei Chang Shen / DMemWin

Dependencies:   emwin_lib

Fork of DMemWin by Embedded Artists

png/pngwio.c@4:20387dbf7ecf, 2016-06-02 (annotated)

Committer:
destinyXfate
Date:
Thu Jun 02 04:55:08 2016 +0000
Revision:
4:20387dbf7ecf
Parent:
2:0e2ef1edf01b 
;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
destinyXfate 2:0e2ef1edf01b 1
destinyXfate 2:0e2ef1edf01b 2 /* pngwio.c - functions for data output
destinyXfate 2:0e2ef1edf01b 3 *
destinyXfate 2:0e2ef1edf01b 4 * Last changed in libpng 1.2.13 November 13, 2006
destinyXfate 2:0e2ef1edf01b 5 * For conditions of distribution and use, see copyright notice in png.h
destinyXfate 2:0e2ef1edf01b 6 * Copyright (c) 1998-2002 Glenn Randers-Pehrson
destinyXfate 2:0e2ef1edf01b 7 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
destinyXfate 2:0e2ef1edf01b 8 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
destinyXfate 2:0e2ef1edf01b 9 *
destinyXfate 2:0e2ef1edf01b 10 * This file provides a location for all output. Users who need
destinyXfate 2:0e2ef1edf01b 11 * special handling are expected to write functions that have the same
destinyXfate 2:0e2ef1edf01b 12 * arguments as these and perform similar functions, but that possibly
destinyXfate 2:0e2ef1edf01b 13 * use different output methods. Note that you shouldn't change these
destinyXfate 2:0e2ef1edf01b 14 * functions, but rather write replacement functions and then change
destinyXfate 2:0e2ef1edf01b 15 * them at run time with png_set_write_fn(...).
destinyXfate 2:0e2ef1edf01b 16 */
destinyXfate 2:0e2ef1edf01b 17
destinyXfate 2:0e2ef1edf01b 18 #define PNG_INTERNAL
destinyXfate 2:0e2ef1edf01b 19 #include "png.h"
destinyXfate 2:0e2ef1edf01b 20 #ifdef PNG_WRITE_SUPPORTED
destinyXfate 2:0e2ef1edf01b 21
destinyXfate 2:0e2ef1edf01b 22 /* Write the data to whatever output you are using. The default routine
destinyXfate 2:0e2ef1edf01b 23 writes to a file pointer. Note that this routine sometimes gets called
destinyXfate 2:0e2ef1edf01b 24 with very small lengths, so you should implement some kind of simple
destinyXfate 2:0e2ef1edf01b 25 buffering if you are using unbuffered writes. This should never be asked
destinyXfate 2:0e2ef1edf01b 26 to write more than 64K on a 16 bit machine. */
destinyXfate 2:0e2ef1edf01b 27
destinyXfate 2:0e2ef1edf01b 28 void /* PRIVATE */
destinyXfate 2:0e2ef1edf01b 29 png_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
destinyXfate 2:0e2ef1edf01b 30 {
destinyXfate 2:0e2ef1edf01b 31 if (png_ptr->write_data_fn != NULL )
destinyXfate 2:0e2ef1edf01b 32 (*(png_ptr->write_data_fn))(png_ptr, data, length);
destinyXfate 2:0e2ef1edf01b 33 else
destinyXfate 2:0e2ef1edf01b 34 png_error(png_ptr, "Call to NULL write function");
destinyXfate 2:0e2ef1edf01b 35 }
destinyXfate 2:0e2ef1edf01b 36
destinyXfate 2:0e2ef1edf01b 37 #if !defined(PNG_NO_STDIO)
destinyXfate 2:0e2ef1edf01b 38 /* This is the function that does the actual writing of data. If you are
destinyXfate 2:0e2ef1edf01b 39 not writing to a standard C stream, you should create a replacement
destinyXfate 2:0e2ef1edf01b 40 write_data function and use it at run time with png_set_write_fn(), rather
destinyXfate 2:0e2ef1edf01b 41 than changing the library. */
destinyXfate 2:0e2ef1edf01b 42 #ifndef USE_FAR_KEYWORD
destinyXfate 2:0e2ef1edf01b 43 void PNGAPI
destinyXfate 2:0e2ef1edf01b 44 png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
destinyXfate 2:0e2ef1edf01b 45 {
destinyXfate 2:0e2ef1edf01b 46 png_uint_32 check;
destinyXfate 2:0e2ef1edf01b 47
destinyXfate 2:0e2ef1edf01b 48 if(png_ptr == NULL) return;
destinyXfate 2:0e2ef1edf01b 49 #if defined(_WIN32_WCE)
destinyXfate 2:0e2ef1edf01b 50 if ( !WriteFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) )
destinyXfate 2:0e2ef1edf01b 51 check = 0;
destinyXfate 2:0e2ef1edf01b 52 #else
destinyXfate 2:0e2ef1edf01b 53 check = fwrite(data, 1, length, (png_FILE_p)(png_ptr->io_ptr));
destinyXfate 2:0e2ef1edf01b 54 #endif
destinyXfate 2:0e2ef1edf01b 55 if (check != length)
destinyXfate 2:0e2ef1edf01b 56 png_error(png_ptr, "Write Error");
destinyXfate 2:0e2ef1edf01b 57 }
destinyXfate 2:0e2ef1edf01b 58 #else
destinyXfate 2:0e2ef1edf01b 59 /* this is the model-independent version. Since the standard I/O library
destinyXfate 2:0e2ef1edf01b 60 can't handle far buffers in the medium and small models, we have to copy
destinyXfate 2:0e2ef1edf01b 61 the data.
destinyXfate 2:0e2ef1edf01b 62 */
destinyXfate 2:0e2ef1edf01b 63
destinyXfate 2:0e2ef1edf01b 64 #define NEAR_BUF_SIZE 1024
destinyXfate 2:0e2ef1edf01b 65 #define MIN(a,b) (a <= b ? a : b)
destinyXfate 2:0e2ef1edf01b 66
destinyXfate 2:0e2ef1edf01b 67 void PNGAPI
destinyXfate 2:0e2ef1edf01b 68 png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
destinyXfate 2:0e2ef1edf01b 69 {
destinyXfate 2:0e2ef1edf01b 70 png_uint_32 check;
destinyXfate 2:0e2ef1edf01b 71 png_byte *near_data; /* Needs to be "png_byte *" instead of "png_bytep" */
destinyXfate 2:0e2ef1edf01b 72 png_FILE_p io_ptr;
destinyXfate 2:0e2ef1edf01b 73
destinyXfate 2:0e2ef1edf01b 74 if(png_ptr == NULL) return;
destinyXfate 2:0e2ef1edf01b 75 /* Check if data really is near. If so, use usual code. */
destinyXfate 2:0e2ef1edf01b 76 near_data = (png_byte *)CVT_PTR_NOCHECK(data);
destinyXfate 2:0e2ef1edf01b 77 io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr);
destinyXfate 2:0e2ef1edf01b 78 if ((png_bytep)near_data == data)
destinyXfate 2:0e2ef1edf01b 79 {
destinyXfate 2:0e2ef1edf01b 80 #if defined(_WIN32_WCE)
destinyXfate 2:0e2ef1edf01b 81 if ( !WriteFile(io_ptr, near_data, length, &check, NULL) )
destinyXfate 2:0e2ef1edf01b 82 check = 0;
destinyXfate 2:0e2ef1edf01b 83 #else
destinyXfate 2:0e2ef1edf01b 84 check = fwrite(near_data, 1, length, io_ptr);
destinyXfate 2:0e2ef1edf01b 85 #endif
destinyXfate 2:0e2ef1edf01b 86 }
destinyXfate 2:0e2ef1edf01b 87 else
destinyXfate 2:0e2ef1edf01b 88 {
destinyXfate 2:0e2ef1edf01b 89 png_byte buf[NEAR_BUF_SIZE];
destinyXfate 2:0e2ef1edf01b 90 png_size_t written, remaining, err;
destinyXfate 2:0e2ef1edf01b 91 check = 0;
destinyXfate 2:0e2ef1edf01b 92 remaining = length;
destinyXfate 2:0e2ef1edf01b 93 do
destinyXfate 2:0e2ef1edf01b 94 {
destinyXfate 2:0e2ef1edf01b 95 written = MIN(NEAR_BUF_SIZE, remaining);
destinyXfate 2:0e2ef1edf01b 96 png_memcpy(buf, data, written); /* copy far buffer to near buffer */
destinyXfate 2:0e2ef1edf01b 97 #if defined(_WIN32_WCE)
destinyXfate 2:0e2ef1edf01b 98 if ( !WriteFile(io_ptr, buf, written, &err, NULL) )
destinyXfate 2:0e2ef1edf01b 99 err = 0;
destinyXfate 2:0e2ef1edf01b 100 #else
destinyXfate 2:0e2ef1edf01b 101 err = fwrite(buf, 1, written, io_ptr);
destinyXfate 2:0e2ef1edf01b 102 #endif
destinyXfate 2:0e2ef1edf01b 103 if (err != written)
destinyXfate 2:0e2ef1edf01b 104 break;
destinyXfate 2:0e2ef1edf01b 105 else
destinyXfate 2:0e2ef1edf01b 106 check += err;
destinyXfate 2:0e2ef1edf01b 107 data += written;
destinyXfate 2:0e2ef1edf01b 108 remaining -= written;
destinyXfate 2:0e2ef1edf01b 109 }
destinyXfate 2:0e2ef1edf01b 110 while (remaining != 0);
destinyXfate 2:0e2ef1edf01b 111 }
destinyXfate 2:0e2ef1edf01b 112 if (check != length)
destinyXfate 2:0e2ef1edf01b 113 png_error(png_ptr, "Write Error");
destinyXfate 2:0e2ef1edf01b 114 }
destinyXfate 2:0e2ef1edf01b 115
destinyXfate 2:0e2ef1edf01b 116 #endif
destinyXfate 2:0e2ef1edf01b 117 #endif
destinyXfate 2:0e2ef1edf01b 118
destinyXfate 2:0e2ef1edf01b 119 /* This function is called to output any data pending writing (normally
destinyXfate 2:0e2ef1edf01b 120 to disk). After png_flush is called, there should be no data pending
destinyXfate 2:0e2ef1edf01b 121 writing in any buffers. */
destinyXfate 2:0e2ef1edf01b 122 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
destinyXfate 2:0e2ef1edf01b 123 void /* PRIVATE */
destinyXfate 2:0e2ef1edf01b 124 png_flush(png_structp png_ptr)
destinyXfate 2:0e2ef1edf01b 125 {
destinyXfate 2:0e2ef1edf01b 126 if (png_ptr->output_flush_fn != NULL)
destinyXfate 2:0e2ef1edf01b 127 (*(png_ptr->output_flush_fn))(png_ptr);
destinyXfate 2:0e2ef1edf01b 128 }
destinyXfate 2:0e2ef1edf01b 129
destinyXfate 2:0e2ef1edf01b 130 #if !defined(PNG_NO_STDIO)
destinyXfate 2:0e2ef1edf01b 131 void PNGAPI
destinyXfate 2:0e2ef1edf01b 132 png_default_flush(png_structp png_ptr)
destinyXfate 2:0e2ef1edf01b 133 {
destinyXfate 2:0e2ef1edf01b 134 #if !defined(_WIN32_WCE)
destinyXfate 2:0e2ef1edf01b 135 png_FILE_p io_ptr;
destinyXfate 2:0e2ef1edf01b 136 #endif
destinyXfate 2:0e2ef1edf01b 137 if(png_ptr == NULL) return;
destinyXfate 2:0e2ef1edf01b 138 #if !defined(_WIN32_WCE)
destinyXfate 2:0e2ef1edf01b 139 io_ptr = (png_FILE_p)CVT_PTR((png_ptr->io_ptr));
destinyXfate 2:0e2ef1edf01b 140 if (io_ptr != NULL)
destinyXfate 2:0e2ef1edf01b 141 fflush(io_ptr);
destinyXfate 2:0e2ef1edf01b 142 #endif
destinyXfate 2:0e2ef1edf01b 143 }
destinyXfate 2:0e2ef1edf01b 144 #endif
destinyXfate 2:0e2ef1edf01b 145 #endif
destinyXfate 2:0e2ef1edf01b 146
destinyXfate 2:0e2ef1edf01b 147 /* This function allows the application to supply new output functions for
destinyXfate 2:0e2ef1edf01b 148 libpng if standard C streams aren't being used.
destinyXfate 2:0e2ef1edf01b 149
destinyXfate 2:0e2ef1edf01b 150 This function takes as its arguments:
destinyXfate 2:0e2ef1edf01b 151 png_ptr - pointer to a png output data structure
destinyXfate 2:0e2ef1edf01b 152 io_ptr - pointer to user supplied structure containing info about
destinyXfate 2:0e2ef1edf01b 153 the output functions. May be NULL.
destinyXfate 2:0e2ef1edf01b 154 write_data_fn - pointer to a new output function that takes as its
destinyXfate 2:0e2ef1edf01b 155 arguments a pointer to a png_struct, a pointer to
destinyXfate 2:0e2ef1edf01b 156 data to be written, and a 32-bit unsigned int that is
destinyXfate 2:0e2ef1edf01b 157 the number of bytes to be written. The new write
destinyXfate 2:0e2ef1edf01b 158 function should call png_error(png_ptr, "Error msg")
destinyXfate 2:0e2ef1edf01b 159 to exit and output any fatal error messages.
destinyXfate 2:0e2ef1edf01b 160 flush_data_fn - pointer to a new flush function that takes as its
destinyXfate 2:0e2ef1edf01b 161 arguments a pointer to a png_struct. After a call to
destinyXfate 2:0e2ef1edf01b 162 the flush function, there should be no data in any buffers
destinyXfate 2:0e2ef1edf01b 163 or pending transmission. If the output method doesn't do
destinyXfate 2:0e2ef1edf01b 164 any buffering of ouput, a function prototype must still be
destinyXfate 2:0e2ef1edf01b 165 supplied although it doesn't have to do anything. If
destinyXfate 2:0e2ef1edf01b 166 PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile
destinyXfate 2:0e2ef1edf01b 167 time, output_flush_fn will be ignored, although it must be
destinyXfate 2:0e2ef1edf01b 168 supplied for compatibility. */
destinyXfate 2:0e2ef1edf01b 169 void PNGAPI
destinyXfate 2:0e2ef1edf01b 170 png_set_write_fn(png_structp png_ptr, png_voidp io_ptr,
destinyXfate 2:0e2ef1edf01b 171 png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)
destinyXfate 2:0e2ef1edf01b 172 {
destinyXfate 2:0e2ef1edf01b 173 if(png_ptr == NULL) return;
destinyXfate 2:0e2ef1edf01b 174 png_ptr->io_ptr = io_ptr;
destinyXfate 2:0e2ef1edf01b 175
destinyXfate 2:0e2ef1edf01b 176 #if !defined(PNG_NO_STDIO)
destinyXfate 2:0e2ef1edf01b 177 if (write_data_fn != NULL)
destinyXfate 2:0e2ef1edf01b 178 png_ptr->write_data_fn = write_data_fn;
destinyXfate 2:0e2ef1edf01b 179 else
destinyXfate 2:0e2ef1edf01b 180 png_ptr->write_data_fn = png_default_write_data;
destinyXfate 2:0e2ef1edf01b 181 #else
destinyXfate 2:0e2ef1edf01b 182 png_ptr->write_data_fn = write_data_fn;
destinyXfate 2:0e2ef1edf01b 183 #endif
destinyXfate 2:0e2ef1edf01b 184
destinyXfate 2:0e2ef1edf01b 185 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
destinyXfate 2:0e2ef1edf01b 186 #if !defined(PNG_NO_STDIO)
destinyXfate 2:0e2ef1edf01b 187 if (output_flush_fn != NULL)
destinyXfate 2:0e2ef1edf01b 188 png_ptr->output_flush_fn = output_flush_fn;
destinyXfate 2:0e2ef1edf01b 189 else
destinyXfate 2:0e2ef1edf01b 190 png_ptr->output_flush_fn = png_default_flush;
destinyXfate 2:0e2ef1edf01b 191 #else
destinyXfate 2:0e2ef1edf01b 192 png_ptr->output_flush_fn = output_flush_fn;
destinyXfate 2:0e2ef1edf01b 193 #endif
destinyXfate 2:0e2ef1edf01b 194 #endif /* PNG_WRITE_FLUSH_SUPPORTED */
destinyXfate 2:0e2ef1edf01b 195
destinyXfate 2:0e2ef1edf01b 196 /* It is an error to read while writing a png file */
destinyXfate 2:0e2ef1edf01b 197 if (png_ptr->read_data_fn != NULL)
destinyXfate 2:0e2ef1edf01b 198 {
destinyXfate 2:0e2ef1edf01b 199 png_ptr->read_data_fn = NULL;
destinyXfate 2:0e2ef1edf01b 200 png_warning(png_ptr,
destinyXfate 2:0e2ef1edf01b 201 "Attempted to set both read_data_fn and write_data_fn in");
destinyXfate 2:0e2ef1edf01b 202 png_warning(png_ptr,
destinyXfate 2:0e2ef1edf01b 203 "the same structure. Resetting read_data_fn to NULL.");
destinyXfate 2:0e2ef1edf01b 204 }
destinyXfate 2:0e2ef1edf01b 205 }
destinyXfate 2:0e2ef1edf01b 206
destinyXfate 2:0e2ef1edf01b 207 #if defined(USE_FAR_KEYWORD)
destinyXfate 2:0e2ef1edf01b 208 #if defined(_MSC_VER)
destinyXfate 2:0e2ef1edf01b 209 void *png_far_to_near(png_structp png_ptr,png_voidp ptr, int check)
destinyXfate 2:0e2ef1edf01b 210 {
destinyXfate 2:0e2ef1edf01b 211 void *near_ptr;
destinyXfate 2:0e2ef1edf01b 212 void FAR *far_ptr;
destinyXfate 2:0e2ef1edf01b 213 FP_OFF(near_ptr) = FP_OFF(ptr);
destinyXfate 2:0e2ef1edf01b 214 far_ptr = (void FAR *)near_ptr;
destinyXfate 2:0e2ef1edf01b 215 if(check != 0)
destinyXfate 2:0e2ef1edf01b 216 if(FP_SEG(ptr) != FP_SEG(far_ptr))
destinyXfate 2:0e2ef1edf01b 217 png_error(png_ptr,"segment lost in conversion");
destinyXfate 2:0e2ef1edf01b 218 return(near_ptr);
destinyXfate 2:0e2ef1edf01b 219 }
destinyXfate 2:0e2ef1edf01b 220 # else
destinyXfate 2:0e2ef1edf01b 221 void *png_far_to_near(png_structp png_ptr,png_voidp ptr, int check)
destinyXfate 2:0e2ef1edf01b 222 {
destinyXfate 2:0e2ef1edf01b 223 void *near_ptr;
destinyXfate 2:0e2ef1edf01b 224 void FAR *far_ptr;
destinyXfate 2:0e2ef1edf01b 225 near_ptr = (void FAR *)ptr;
destinyXfate 2:0e2ef1edf01b 226 far_ptr = (void FAR *)near_ptr;
destinyXfate 2:0e2ef1edf01b 227 if(check != 0)
destinyXfate 2:0e2ef1edf01b 228 if(far_ptr != ptr)
destinyXfate 2:0e2ef1edf01b 229 png_error(png_ptr,"segment lost in conversion");
destinyXfate 2:0e2ef1edf01b 230 return(near_ptr);
destinyXfate 2:0e2ef1edf01b 231 }
destinyXfate 2:0e2ef1edf01b 232 # endif
destinyXfate 2:0e2ef1edf01b 233 # endif
destinyXfate 2:0e2ef1edf01b 234 #endif /* PNG_WRITE_SUPPORTED */
destinyXfate 2:0e2ef1edf01b 235