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fogus/lz77.c

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lz77.c
/* PROG1.C */
/* Simple Hashing LZ77 Sliding Dictionary Compression Program */
/* By Rich Geldreich, Jr. October, 1993 */
/* Originally compiled with QuickC v2.5 in the small model. */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
/* set this to 1 for a greedy encoder */
#define GREEDY 0
/* ratio vs. speed constant */
/* the larger this constant, the better the compression */
#define MAXCOMPARES 75
/* unused entry flag */
#define NIL 0xFFFF
/* bits per symbol- normally 8 for general purpose compression */
#define CHARBITS 8
/* minimum match length & maximum match length */
#define THRESHOLD 2
#define MATCHBITS 4
#define MAXMATCH ((1 << MATCHBITS) + THRESHOLD - 1)
/* sliding dictionary size and hash table's size */
/* some combinations of HASHBITS and THRESHOLD values will not work
correctly because of the way this program hashes strings */
#define DICTBITS 13
#define HASHBITS 10
#define DICTSIZE (1 << DICTBITS)
#define HASHSIZE (1 << HASHBITS)
/* # bits to shift after each XOR hash */
/* this constant must be high enough so that only THRESHOLD + 1
characters are in the hash accumulator at one time */
#define SHIFTBITS ((HASHBITS + THRESHOLD) / (THRESHOLD + 1))
/* sector size constants */
#define SECTORBIT 10
#define SECTORLEN (1 << SECTORBIT)
#define SECTORAND ((0xFFFF << SECTORBIT) & 0xFFFF)
/* dictionary plus MAXMATCH extra chars for string comparisions */
unsigned char
dict[DICTSIZE + MAXMATCH];
/* hashtable & link list table */
unsigned int
hash[HASHSIZE],
nextlink[DICTSIZE];
/* misc. global variables */
unsigned int
matchlength,
matchpos,
bitbuf,
bitsin,
masks[17] = {0,1,3,7,15,31,63,127,255,511,1023,2047,4095,8191,16383,32767,65535};
FILE *infile, *outfile;
/* writes multiple bit codes to the output stream */
void SendBits(unsigned int bits, unsigned int numbits)
{
bitbuf |= (bits << bitsin);
bitsin += numbits;
if (bitsin > 16) /* special case when # bits in buffer exceeds 16 */
{
if (putc(bitbuf & 0xFF, outfile) == EOF)
{
printf("\nerror writing to output file");
exit(EXIT_FAILURE);
}
bitbuf = bits >> (8 - (bitsin - numbits));
bitsin -= 8;
}
while (bitsin >= 8)
{
if (putc(bitbuf & 0xFF, outfile) == EOF)
{
printf("\nerror writing to output file");
exit(EXIT_FAILURE);
}
bitbuf >>= 8;
bitsin -= 8;
}
}
/* reads multiple bit codes from the input stream */
unsigned int ReadBits(unsigned int numbits)
{
register unsigned int i;
i = bitbuf >> (8 - bitsin);
while (numbits > bitsin)
{
if ((bitbuf = getc(infile)) == EOF)
{
printf("\nerror reading from input file");
exit(EXIT_FAILURE);
}
i |= (bitbuf << bitsin);
bitsin += 8;
}
bitsin -= numbits;
return (i & masks[numbits]);
}
/* sends a match to the output stream */
void SendMatch(unsigned int matchlen, unsigned int matchdistance)
{
SendBits(1, 1);
SendBits(matchlen - (THRESHOLD + 1), MATCHBITS);
SendBits(matchdistance, DICTBITS);
}
/* sends one character (or literal) to the output stream */
void SendChar(unsigned int character)
{
SendBits(0, 1);
SendBits(character, CHARBITS);
}
/* initializes the search structures needed for compression */
void InitEncode(void)
{
register unsigned int i;
for (i = 0; i < HASHSIZE; i++) hash[i] = NIL;
nextlink[DICTSIZE] = NIL;
}
/* loads dictionary with characters from the input stream */
unsigned int LoadDict(unsigned int dictpos)
{
register unsigned int i, j;
if ((i = fread(&dict[dictpos], sizeof (char), SECTORLEN, infile)) == EOF)
{
printf("\nerror reading from input file");
exit(EXIT_FAILURE);
}
/* since the dictionary is a ring buffer, copy the characters at
the very start of the dictionary to the end */
if (dictpos == 0)
{
for (j = 0; j < MAXMATCH; j++) dict[j + DICTSIZE] = dict[j];
}
return i;
}
/* deletes data from the dictionary search structures */
/* this is only done when the number of bytes to be
compressed exceeds the dictionary's size */
void DeleteData(unsigned int dictpos)
{
register unsigned int i, j;
j = dictpos; /* put dictpos in register for more speed */
/* delete all references to the sector being deleted */
for (i = 0; i < DICTSIZE; i++)
if ((nextlink[i] & SECTORAND) == j) nextlink[i] = NIL;
for (i = 0; i < HASHSIZE; i++)
if ((hash[i] & SECTORAND) == j) hash[i] = NIL;
}
/* hash data just entered into dictionary */
/* XOR hashing is used here, but practically any hash function will work */
void HashData(unsigned int dictpos, unsigned int bytestodo)
{
register unsigned int i, j, k;
if (bytestodo <= THRESHOLD) /* not enough bytes in sector for match? */
for (i = 0; i < bytestodo; i++) nextlink[dictpos + i] = NIL;
else
{
/* matches can't cross sector boundries */
for (i = bytestodo - THRESHOLD; i < bytestodo; i++)
nextlink[dictpos + i] = NIL;
j = (((unsigned int)dict[dictpos]) << SHIFTBITS) ^ dict[dictpos + 1];
k = dictpos + bytestodo - THRESHOLD; /* calculate end of sector */
for (i = dictpos; i < k; i++)
{
nextlink[i] = hash[j = (((j << SHIFTBITS) & (HASHSIZE - 1)) ^ dict[i + THRESHOLD])];
hash[j] = i;
}
}
}
/* finds match for string at position dictpos */
/* this search code finds the longest AND closest
match for the string at dictpos */
void FindMatch(unsigned int dictpos, unsigned int startlen)
{
register unsigned int i, j, k;
unsigned char l;
i = dictpos; matchlength = startlen; k = MAXCOMPARES;
l = dict[dictpos + matchlength];
do
{
if ((i = nextlink[i]) == NIL) return; /* get next string in list */
if (dict[i + matchlength] == l) /* possible larger match? */
{
for (j = 0; j < MAXMATCH; j++) /* compare strings */
if (dict[dictpos + j] != dict[i + j]) break;
if (j > matchlength) /* found larger match? */
{
matchlength = j;
matchpos = i;
if (matchlength == MAXMATCH) return; /* exit if largest possible match */
l = dict[dictpos + matchlength];
}
}
}
while (--k); /* keep on trying until we run out of chances */
}
/* finds dictionary matches for characters in current sector */
void DictSearch(unsigned int dictpos, unsigned int bytestodo)
{
register unsigned int i, j;
#if (GREEDY == 0)
unsigned int matchlen1, matchpos1;
/* non-greedy search loop (slow) */
i = dictpos; j = bytestodo;
while (j) /* loop while there are still characters left to be compressed */
{
FindMatch(i, THRESHOLD);
if (matchlength > THRESHOLD)
{
matchlen1 = matchlength;
matchpos1 = matchpos;
for ( ; ; )
{
FindMatch(i + 1, matchlen1);
if (matchlength > matchlen1)
{
matchlen1 = matchlength;
matchpos1 = matchpos;
SendChar(dict[i++]);
j--;
}
else
{
if (matchlen1 > j)
{
matchlen1 = j;
if (matchlen1 <= THRESHOLD) { SendChar(dict[i++]); j--; break; }
}
SendMatch(matchlen1, (i - matchpos1) & (DICTSIZE - 1));
i += matchlen1;
j -= matchlen1;
break;
}
}
}
else
{
SendChar(dict[i++]);
j--;
}
}
#else
/* greedy search loop (fast) */
i = dictpos; j = bytestodo;
while (j) /* loop while there are still characters left to be compressed */
{
FindMatch(i, THRESHOLD);
if (matchlength > j) matchlength = j; /* clamp matchlength */
if (matchlength > THRESHOLD) /* valid match? */
{
SendMatch(matchlength, (i - matchpos) & (DICTSIZE - 1));
i += matchlength;
j -= matchlength;
}
else
{
SendChar(dict[i++]);
j--;
}
}
#endif
}
/* main encoder */
void Encode (void)
{
unsigned int dictpos, deleteflag, sectorlen;
unsigned long bytescompressed;
InitEncode();
dictpos = deleteflag = 0;
bytescompressed = 0;
while (1)
{
/* delete old data from dictionary */
if (deleteflag) DeleteData(dictpos);
/* grab more data to compress */
if ((sectorlen = LoadDict(dictpos)) == 0) break;
/* hash the data */
HashData(dictpos, sectorlen);
/* find dictionary matches */
DictSearch(dictpos, sectorlen);
bytescompressed += sectorlen;
printf("\r%ld", bytescompressed);
dictpos += SECTORLEN;
/* wrap back to beginning of dictionary when its full */
if (dictpos == DICTSIZE)
{
dictpos = 0;
deleteflag = 1; /* ok to delete now */
}
}
/* Send EOF flag */
SendMatch(MAXMATCH + 1, 0);
/* Flush bit buffer */
if (bitsin) SendBits(0, 8 - bitsin);
return;
}
/* main decoder */
void Decode (void)
{
register unsigned int i, j, k;
unsigned long bytesdecompressed;
i = 0;
bytesdecompressed = 0;
for ( ; ; )
{
if (ReadBits(1) == 0) /* character or match? */
{
dict[i++] = ReadBits(CHARBITS);
if (i == DICTSIZE)
{
if (fwrite(&dict, sizeof (char), DICTSIZE, outfile) == EOF)
{
printf("\nerror writing to output file");
exit(EXIT_FAILURE);
}
i = 0;
bytesdecompressed += DICTSIZE;
printf("\r%ld", bytesdecompressed);
}
}
else
{
/* get match length from input stream */
k = (THRESHOLD + 1) + ReadBits(MATCHBITS);
if (k == (MAXMATCH + 1)) /* Check for EOF flag */
{
if (fwrite(&dict, sizeof (char), i, outfile) == EOF)
{
printf("\nerror writing to output file");
exit(EXIT_FAILURE);
}
bytesdecompressed += i;
printf("\r%ld", bytesdecompressed);
return;
}
/* get match position from input stream */
j = ((i - ReadBits(DICTBITS)) & (DICTSIZE - 1));
if ((i + k) >= DICTSIZE)
{
do
{
dict[i++] = dict[j++];
j &= (DICTSIZE - 1);
if (i == DICTSIZE)
{
if (fwrite(&dict, sizeof (char), DICTSIZE, outfile) == EOF)
{
printf("\nerror writing to output file");
exit(EXIT_FAILURE);
}
i = 0;
bytesdecompressed += DICTSIZE;
printf("\r%ld", bytesdecompressed);
}
}
while (--k);
}
else
{
if ((j + k) >= DICTSIZE)
{
do
{
dict[i++] = dict[j++];
j &= (DICTSIZE - 1);
}
while (--k);
}
else
{
do
{
dict[i++] = dict[j++];
}
while (--k);
}
}
}
}
}
int main(int argc, char *argv[])
{
char *s;
if (argc != 4)
{
printf("\n'prog1 e file1 file2' encodes file1 into file2.\n"
"'prog1 d file2 file1' decodes file2 into file1.\n");
return EXIT_FAILURE;
}
if ((s = argv[1], s[1] || strpbrk(s, "DEde") == NULL)
|| (s = argv[2], (infile = fopen(s, "rb")) == NULL)
|| (s = argv[3], (outfile = fopen(s, "wb")) == NULL)) {
printf("??? %s\n", s); return EXIT_FAILURE;
}
/* allocate 4k I/O buffers for a little speed */
setvbuf( infile, NULL, _IOFBF, 4096);
setvbuf( outfile, NULL, _IOFBF, 4096);
if (toupper(*argv[1]) == 'E')
{
printf("Compressing %s to %s\n", argv[2], argv[3]);
Encode();
}
else
{
printf("Decompressing %s to %s\n", argv[2], argv[3]);
Decode();
}
fclose(infile); fclose(outfile);
return EXIT_SUCCESS;
}
Raw
lz77a.c
/* PROG2.C */
/* Simple Hashing LZ77 Sliding Dictionary Compression Program */
/* By Rich Geldreich, Jr. October, 1993 */
/* Originally compiled with QuickC v2.5 in the small model. */
/* This program uses more efficient code to delete strings from */
/* the sliding dictionary compared to PROG1.C, at the expense of */
/* greater memory requirements. See the HashData and DeleteData */
/* subroutines. */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
/* set this to 1 for a greedy encoder */
#define GREEDY 0
/* ratio vs. speed constant */
/* the larger this constant, the better the compression */
#define MAXCOMPARES 75
/* unused entry flag */
#define NIL 0xFFFF
/* bits per symbol- normally 8 for general purpose compression */
#define CHARBITS 8
/* minimum match length & maximum match length */
#define THRESHOLD 2
#define MATCHBITS 4
#define MAXMATCH ((1 << MATCHBITS) + THRESHOLD - 1)
/* sliding dictionary size and hash table's size */
/* some combinations of HASHBITS and THRESHOLD values will not work
correctly because of the way this program hashes strings */
#define DICTBITS 13
#define HASHBITS 10
#define DICTSIZE (1 << DICTBITS)
#define HASHSIZE (1 << HASHBITS)
/* # bits to shift after each XOR hash */
/* this constant must be high enough so that only THRESHOLD + 1
characters are in the hash accumulator at one time */
#define SHIFTBITS ((HASHBITS + THRESHOLD) / (THRESHOLD + 1))
/* sector size constants */
#define SECTORBIT 10
#define SECTORLEN (1 << SECTORBIT)
#define HASHFLAG1 0x8000
#define HASHFLAG2 0x7FFF
/* dictionary plus MAXMATCH extra chars for string comparisions */
unsigned char
dict[DICTSIZE + MAXMATCH];
/* hashtable & link list tables */
unsigned int
hash[HASHSIZE],
nextlink[DICTSIZE],
lastlink[DICTSIZE];
/* misc. global variables */
unsigned int
matchlength,
matchpos,
bitbuf,
bitsin,
masks[17] = {0,1,3,7,15,31,63,127,255,511,1023,2047,4095,8191,16383,32767,65535};
FILE *infile, *outfile;
/* writes multiple bit codes to the output stream */
void SendBits(unsigned int bits, unsigned int numbits)
{
bitbuf |= (bits << bitsin);
bitsin += numbits;
if (bitsin > 16) /* special case when # bits in buffer exceeds 16 */
{
if (putc(bitbuf & 0xFF, outfile) == EOF)
{
printf("\nerror writing to output file");
exit(EXIT_FAILURE);
}
bitbuf = bits >> (8 - (bitsin - numbits));
bitsin -= 8;
}
while (bitsin >= 8)
{
if (putc(bitbuf & 0xFF, outfile) == EOF)
{
printf("\nerror writing to output file");
exit(EXIT_FAILURE);
}
bitbuf >>= 8;
bitsin -= 8;
}
}
/* reads multiple bit codes from the input stream */
unsigned int ReadBits(unsigned int numbits)
{
register unsigned int i;
i = bitbuf >> (8 - bitsin);
while (numbits > bitsin)
{
if ((bitbuf = getc(infile)) == EOF)
{
printf("\nerror reading from input file");
exit(EXIT_FAILURE);
}
i |= (bitbuf << bitsin);
bitsin += 8;
}
bitsin -= numbits;
return (i & masks[numbits]);
}
/* sends a match to the output stream */
void SendMatch(unsigned int matchlen, unsigned int matchdistance)
{
SendBits(1, 1);
SendBits(matchlen - (THRESHOLD + 1), MATCHBITS);
SendBits(matchdistance, DICTBITS);
}
/* sends one character (or literal) to the output stream */
void SendChar(unsigned int character)
{
SendBits(0, 1);
SendBits(character, CHARBITS);
}
/* initializes the search structures needed for compression */
void InitEncode(void)
{
register unsigned int i;
for (i = 0; i < HASHSIZE; i++) hash[i] = NIL;
nextlink[DICTSIZE] = NIL;
}
/* loads dictionary with characters from the input stream */
unsigned int LoadDict(unsigned int dictpos)
{
register unsigned int i, j;
if ((i = fread(&dict[dictpos], sizeof (char), SECTORLEN, infile)) == EOF)
{
printf("\nerror reading from input file");
exit(EXIT_FAILURE);
}
/* since the dictionary is a ring buffer, copy the characters at
the very start of the dictionary to the end */
if (dictpos == 0)
{
for (j = 0; j < MAXMATCH; j++) dict[j + DICTSIZE] = dict[j];
}
return i;
}
/* deletes data from the dictionary search structures */
/* this is only done when the number of bytes to be */
/* compressed exceeds the dictionary's size */
void DeleteData(unsigned int dictpos)
{
register unsigned int i, j, k;
/* delete all references to the sector being deleted */
k = dictpos + SECTORLEN;
for (i = dictpos; i < k; i++)
{
if ((j = lastlink[i]) & HASHFLAG1)
{
if (j != NIL) hash[j & HASHFLAG2] = NIL;
}
else
nextlink[j] = NIL;
}
}
/* hash data just entered into dictionary */
/* XOR hashing is used here, but practically any hash function will work */
void HashData(unsigned int dictpos, unsigned int bytestodo)
{
register unsigned int i, j, k;
if (bytestodo <= THRESHOLD) /* not enough bytes in sector for match? */
for (i = 0; i < bytestodo; i++)
nextlink[dictpos + i] = lastlink[dictpos + i] = NIL;
else
{
/* matches can't cross sector boundries */
for (i = bytestodo - THRESHOLD; i < bytestodo; i++)
nextlink[dictpos + i] = lastlink[dictpos + i] = NIL;
j = (((unsigned int)dict[dictpos]) << SHIFTBITS) ^ dict[dictpos + 1];
k = dictpos + bytestodo - THRESHOLD; /* calculate end of sector */
for (i = dictpos; i < k; i++)
{
lastlink[i] = (j = (((j << SHIFTBITS) & (HASHSIZE - 1)) ^ dict[i + THRESHOLD])) | HASHFLAG1;
if ((nextlink[i] = hash[j]) != NIL) lastlink[nextlink[i]] = i;
hash[j] = i;
}
}
}
/* finds match for string at position dictpos */
/* this search code finds the longest AND closest */
/* match for the string at dictpos */
void FindMatch(unsigned int dictpos, unsigned int startlen)
{
register unsigned int i, j, k;
unsigned char l;
i = dictpos; matchlength = startlen; k = MAXCOMPARES;
l = dict[dictpos + matchlength];
do
{
if ((i = nextlink[i]) == NIL) return; /* get next string in list */
if (dict[i + matchlength] == l) /* possible larger match? */
{
for (j = 0; j < MAXMATCH; j++) /* compare strings */
if (dict[dictpos + j] != dict[i + j]) break;
if (j > matchlength) /* found larger match? */
{
matchlength = j;
matchpos = i;
if (matchlength == MAXMATCH) return; /* exit if largest possible match */
l = dict[dictpos + matchlength];
}
}
}
while (--k); /* keep on trying until we run out of chances */
}
/* finds dictionary matches for characters in current sector */
void DictSearch(unsigned int dictpos, unsigned int bytestodo)
{
register unsigned int i, j;
#if (GREEDY == 0)
unsigned int matchlen1, matchpos1;
/* non-greedy search loop (slow) */
i = dictpos; j = bytestodo;
while (j) /* loop while there are still characters left to be compressed */
{
FindMatch(i, THRESHOLD);
if (matchlength > THRESHOLD)
{
matchlen1 = matchlength;
matchpos1 = matchpos;
for ( ; ; )
{
FindMatch(i + 1, matchlen1);
if (matchlength > matchlen1)
{
matchlen1 = matchlength;
matchpos1 = matchpos;
SendChar(dict[i++]);
j--;
}
else
{
if (matchlen1 > j)
{
matchlen1 = j;
if (matchlen1 <= THRESHOLD) { SendChar(dict[i++]); j--; break; }
}
SendMatch(matchlen1, (i - matchpos1) & (DICTSIZE - 1));
i += matchlen1;
j -= matchlen1;
break;
}
}
}
else
{
SendChar(dict[i++]);
j--;
}
}
#else
/* greedy search loop (fast) */
i = dictpos; j = bytestodo;
while (j) /* loop while there are still characters left to be compressed */
{
FindMatch(i, THRESHOLD);
if (matchlength > j) matchlength = j; /* clamp matchlength */
if (matchlength > THRESHOLD) /* valid match? */
{
SendMatch(matchlength, (i - matchpos) & (DICTSIZE - 1));
i += matchlength;
j -= matchlength;
}
else
{
SendChar(dict[i++]);
j--;
}
}
#endif
}
/* main encoder */
void Encode (void)
{
unsigned int dictpos, deleteflag, sectorlen;
unsigned long bytescompressed;
InitEncode();
dictpos = deleteflag = 0;
bytescompressed = 0;
while (1)
{
/* delete old data from dictionary */
if (deleteflag) DeleteData(dictpos);
/* grab more data to compress */
if ((sectorlen = LoadDict(dictpos)) == 0) break;
/* hash the data */
HashData(dictpos, sectorlen);
/* find dictionary matches */
DictSearch(dictpos, sectorlen);
bytescompressed += sectorlen;
printf("\r%ld", bytescompressed);
dictpos += SECTORLEN;
/* wrap back to beginning of dictionary when its full */
if (dictpos == DICTSIZE)
{
dictpos = 0;
deleteflag = 1; /* ok to delete now */
}
}
/* Send EOF flag */
SendMatch(MAXMATCH + 1, 0);
/* Flush bit buffer */
if (bitsin) SendBits(0, 8 - bitsin);
return;
}
/* main decoder */
void Decode (void)
{
register unsigned int i, j, k;
unsigned long bytesdecompressed;
i = 0;
bytesdecompressed = 0;
for ( ; ; )
{
if (ReadBits(1) == 0) /* character or match? */
{
dict[i++] = ReadBits(CHARBITS);
if (i == DICTSIZE)
{
if (fwrite(&dict, sizeof (char), DICTSIZE, outfile) == EOF)
{
printf("\nerror writing to output file");
exit(EXIT_FAILURE);
}
i = 0;
bytesdecompressed += DICTSIZE;
printf("\r%ld", bytesdecompressed);
}
}
else
{
/* get match length from input stream */
k = (THRESHOLD + 1) + ReadBits(MATCHBITS);
if (k == (MAXMATCH + 1)) /* Check for EOF flag */
{
if (fwrite(&dict, sizeof (char), i, outfile) == EOF)
{
printf("\nerror writing to output file");
exit(EXIT_FAILURE);
}
bytesdecompressed += i;
printf("\r%ld", bytesdecompressed);
return;
}
/* get match position from input stream */
j = ((i - ReadBits(DICTBITS)) & (DICTSIZE - 1));
if ((i + k) >= DICTSIZE)
{
do
{
dict[i++] = dict[j++];
j &= (DICTSIZE - 1);
if (i == DICTSIZE)
{
if (fwrite(&dict, sizeof (char), DICTSIZE, outfile) == EOF)
{
printf("\nerror writing to output file");
exit(EXIT_FAILURE);
}
i = 0;
bytesdecompressed += DICTSIZE;
printf("\r%ld", bytesdecompressed);
}
}
while (--k);
}
else
{
if ((j + k) >= DICTSIZE)
{
do
{
dict[i++] = dict[j++];
j &= (DICTSIZE - 1);
}
while (--k);
}
else
{
do
{
dict[i++] = dict[j++];
}
while (--k);
}
}
}
}
}
int main(int argc, char *argv[])
{
char *s;
if (argc != 4)
{
printf("\n'prog2 e file1 file2' encodes file1 into file2.\n"
"'prog2 d file2 file1' decodes file2 into file1.\n");
return EXIT_FAILURE;
}
if ((s = argv[1], s[1] || strpbrk(s, "DEde") == NULL)
|| (s = argv[2], (infile = fopen(s, "rb")) == NULL)
|| (s = argv[3], (outfile = fopen(s, "wb")) == NULL)) {
printf("??? %s\n", s); return EXIT_FAILURE;
}
/* allocate 4k I/O buffers */
setvbuf( infile, NULL, _IOFBF, 4096);
setvbuf( outfile, NULL, _IOFBF, 4096);
if (toupper(*argv[1]) == 'E')
{
printf("Compressing %s to %s\n", argv[2], argv[3]);
Encode();
}
else
{
printf("Decompressing %s to %s\n", argv[2], argv[3]);
Decode();
}
fclose(infile); fclose(outfile);
return EXIT_SUCCESS;
}
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