69 lines
1.1 KiB
C
69 lines
1.1 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include "objects.h"
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#include "comp.h"
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static int rle_compress_block(COMP_CTX *ctx, unsigned char *out,
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unsigned int olen, unsigned char *in, unsigned int ilen);
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static int rle_expand_block(COMP_CTX *ctx, unsigned char *out,
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unsigned int olen, unsigned char *in, unsigned int ilen);
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static COMP_METHOD rle_method={
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NID_rle_compression,
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LN_rle_compression,
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NULL,
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NULL,
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rle_compress_block,
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rle_expand_block,
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NULL,
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};
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COMP_METHOD *COMP_rle()
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{
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return(&rle_method);
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}
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static int rle_compress_block(ctx,out,olen,in,ilen)
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COMP_CTX *ctx;
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unsigned char *out;
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unsigned int olen;
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unsigned char *in;
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unsigned int ilen;
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{
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/* int i; */
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if (olen < (ilen+1))
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{
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/* ZZZZZZZZZZZZZZZZZZZZZZ */
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return(-1);
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}
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*(out++)=0;
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memcpy(out,in,ilen);
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return(ilen+1);
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}
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static int rle_expand_block(ctx,out,olen,in,ilen)
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COMP_CTX *ctx;
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unsigned char *out;
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unsigned int olen;
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unsigned char *in;
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unsigned int ilen;
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{
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int i;
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if (olen < (ilen-1))
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{
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/* ZZZZZZZZZZZZZZZZZZZZZZ */
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return(-1);
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}
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i= *(in++);
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if (i == 0)
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{
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memcpy(out,in,ilen-1);
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}
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return(ilen-1);
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}
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