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libksquirrel/kernel/kls_ljpeg/ljpeg2ppm/io.h

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/*
* Copyright (C) 1991, 1992, Thomas G. Lane.
* Part of the Independent JPEG Group's software.
* See the file Copyright for more details.
*
* Copyright (c) 1993 Brian C. Smith, The Regents of the University
* of California
* All rights reserved.
*
* Copyright (c) 1994 Kongji Huang and Brian C. Smith.
* Cornell University
* All rights reserved.
*
* Permission to use, copy, modify, and distribute this software and its
* documentation for any purpose, without fee, and without written agreement is
* hereby granted, provided that the above copyright notice and the following
* two paragraphs appear in all copies of this software.
*
* IN NO EVENT SHALL CORNELL UNIVERSITY BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
* OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF CORNELL
* UNIVERSITY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* CORNELL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND CORNELL UNIVERSITY HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*/
#ifndef _IO
#define _IO
/*
* Size of the input and output buffer
*/
#define JPEG_BUF_SIZE 4096
/*
* The following variables keep track of the input and output
* buffer for the JPEG data.
*/
extern char outputBuffer[JPEG_BUF_SIZE]; /* output buffer */
extern int numOutputBytes; /* bytes in the output buffer */
extern Uchar inputBuffer[JPEG_BUF_SIZE]; /* Input buffer for JPEG data */
extern int numInputBytes; /* bytes in inputBuffer */
extern int maxInputBytes; /* Size of inputBuffer */
extern int inputBufferOffset; /* Offset of current byte */
/*
* the output file pointer.
*/
extern FILE *outFile;
/*
*--------------------------------------------------------------
*
* EmitByte --
*
* Write a single byte out to the output buffer, and
* flush if it's full.
*
* Results:
* None.
*
* Side effects:
* The outp[ut buffer may get flushed.
*
*--------------------------------------------------------------
*/
#define EmitByte(val) { \
if (numOutputBytes >= JPEG_BUF_SIZE) { \
FlushBytes(); \
} \
outputBuffer[numOutputBytes++] = (char)(val); \
}
/*
*--------------------------------------------------------------
*
* GetJpegChar, UnGetJpegChar --
*
* Macros to get the next character from the input stream.
*
* Results:
* GetJpegChar returns the next character in the stream, or EOF
* UnGetJpegChar returns nothing.
*
* Side effects:
* A byte is consumed or put back into the inputBuffer.
*
*--------------------------------------------------------------
*/
#define GetJpegChar() \
((inputBufferOffset < numInputBytes)? \
inputBuffer[inputBufferOffset++]: \
(numInputBytes = 2+ReadJpegData(inputBuffer+2,JPEG_BUF_SIZE-2), \
inputBufferOffset = 2, \
((inputBufferOffset < numInputBytes)? \
inputBuffer[inputBufferOffset++]: \
EOF)))
#define UnGetJpegChar(ch) (inputBuffer[--inputBufferOffset]=(ch))
#endif /* _IO */