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-rwxr-xr-xreference/C/CONTRIB/SNIP/lzhuf.c646
1 files changed, 646 insertions, 0 deletions
diff --git a/reference/C/CONTRIB/SNIP/lzhuf.c b/reference/C/CONTRIB/SNIP/lzhuf.c
new file mode 100755
index 0000000..f1c678b
--- /dev/null
+++ b/reference/C/CONTRIB/SNIP/lzhuf.c
@@ -0,0 +1,646 @@
+/**************************************************************
+ lzhuf.c
+ written by Haruyasu Yoshizaki 1988/11/20
+ some minor changes 1989/04/06
+ comments translated by Haruhiko Okumura 1989/04/07
+ getbit and getbyte modified 1990/03/23 by Paul Edwards
+ so that they would work on machines where integers are
+ not necessarily 16 bits (although ANSI guarantees a
+ minimum of 16). This program has compiled and run with
+ no errors under Turbo C 2.0, Power C, and SAS/C 4.5
+ (running on an IBM mainframe under MVS/XA 2.2). Could
+ people please use YYYY/MM/DD date format so that everyone
+ in the world can know what format the date is in?
+ external storage of filesize changed 1990/04/18 by Paul Edwards to
+ Intel's "little endian" rather than a machine-dependant style so
+ that files produced on one machine with lzhuf can be decoded on
+ any other. "little endian" style was chosen since lzhuf
+ originated on PC's, and therefore they should dictate the
+ standard.
+ initialization of something predicting spaces changed 1990/04/22 by
+ Paul Edwards so that when the compressed file is taken somewhere
+ else, it will decode properly, without changing ascii spaces to
+ ebcdic spaces. This was done by changing the ' ' (space literal)
+ to 0x20 (which is the far most likely character to occur, if you
+ don't know what environment it will be running on.
+**************************************************************/
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+FILE *infile, *outfile;
+static unsigned long int textsize = 0, codesize = 0, printcount = 0;
+
+char wterr[] = "Can't write.";
+
+static void Error(char *message)
+{
+ printf("\n%s\n", message);
+ exit(EXIT_FAILURE);
+}
+
+/********** LZSS compression **********/
+
+#define N 4096 /* buffer size */
+#define F 60 /* lookahead buffer size */
+#define THRESHOLD 2
+#define NIL N /* leaf of tree */
+
+unsigned char
+ text_buf[N + F - 1];
+static int match_position, match_length,
+ lson[N + 1], rson[N + 257], dad[N + 1];
+
+static void InitTree(void) /* initialize trees */
+{
+ int i;
+
+ for (i = N + 1; i <= N + 256; i++)
+ rson[i] = NIL; /* root */
+ for (i = 0; i < N; i++)
+ dad[i] = NIL; /* node */
+}
+
+static void InsertNode(int r) /* insert to tree */
+{
+ int i, p, cmp;
+ unsigned char *key;
+ unsigned c;
+
+ cmp = 1;
+ key = &text_buf[r];
+ p = N + 1 + key[0];
+ rson[r] = lson[r] = NIL;
+ match_length = 0;
+ for ( ; ; ) {
+ if (cmp >= 0) {
+ if (rson[p] != NIL)
+ p = rson[p];
+ else {
+ rson[p] = r;
+ dad[r] = p;
+ return;
+ }
+ } else {
+ if (lson[p] != NIL)
+ p = lson[p];
+ else {
+ lson[p] = r;
+ dad[r] = p;
+ return;
+ }
+ }
+ for (i = 1; i < F; i++)
+ if ((cmp = key[i] - text_buf[p + i]) != 0)
+ break;
+ if (i > THRESHOLD) {
+ if (i > match_length) {
+ match_position = ((r - p) & (N - 1)) - 1;
+ if ((match_length = i) >= F)
+ break;
+ }
+ if (i == match_length) {
+ if ((c = ((r - p) & (N-1)) - 1) < (unsigned)match_position) {
+ match_position = c;
+ }
+ }
+ }
+ }
+ dad[r] = dad[p];
+ lson[r] = lson[p];
+ rson[r] = rson[p];
+ dad[lson[p]] = r;
+ dad[rson[p]] = r;
+ if (rson[dad[p]] == p)
+ rson[dad[p]] = r;
+ else
+ lson[dad[p]] = r;
+ dad[p] = NIL; /* remove p */
+}
+
+static void DeleteNode(int p) /* remove from tree */
+{
+ int q;
+
+ if (dad[p] == NIL)
+ return; /* not registered */
+ if (rson[p] == NIL)
+ q = lson[p];
+ else
+ if (lson[p] == NIL)
+ q = rson[p];
+ else {
+ q = lson[p];
+ if (rson[q] != NIL) {
+ do {
+ q = rson[q];
+ } while (rson[q] != NIL);
+ rson[dad[q]] = lson[q];
+ dad[lson[q]] = dad[q];
+ lson[q] = lson[p];
+ dad[lson[p]] = q;
+ }
+ rson[q] = rson[p];
+ dad[rson[p]] = q;
+ }
+ dad[q] = dad[p];
+ if (rson[dad[p]] == p)
+ rson[dad[p]] = q;
+ else
+ lson[dad[p]] = q;
+ dad[p] = NIL;
+}
+
+/* Huffman coding */
+
+#define N_CHAR (256 - THRESHOLD + F)
+ /* kinds of characters (character code = 0..N_CHAR-1) */
+#define T (N_CHAR * 2 - 1) /* size of table */
+#define R (T - 1) /* position of root */
+#define MAX_FREQ 0x8000 /* updates tree when the */
+typedef unsigned char uchar;
+
+
+/* table for encoding and decoding the upper 6 bits of position */
+
+/* for encoding */
+uchar p_len[64] = {
+ 0x03, 0x04, 0x04, 0x04, 0x05, 0x05, 0x05, 0x05,
+ 0x05, 0x05, 0x05, 0x05, 0x06, 0x06, 0x06, 0x06,
+ 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+ 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+ 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08
+};
+
+uchar p_code[64] = {
+ 0x00, 0x20, 0x30, 0x40, 0x50, 0x58, 0x60, 0x68,
+ 0x70, 0x78, 0x80, 0x88, 0x90, 0x94, 0x98, 0x9C,
+ 0xA0, 0xA4, 0xA8, 0xAC, 0xB0, 0xB4, 0xB8, 0xBC,
+ 0xC0, 0xC2, 0xC4, 0xC6, 0xC8, 0xCA, 0xCC, 0xCE,
+ 0xD0, 0xD2, 0xD4, 0xD6, 0xD8, 0xDA, 0xDC, 0xDE,
+ 0xE0, 0xE2, 0xE4, 0xE6, 0xE8, 0xEA, 0xEC, 0xEE,
+ 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,
+ 0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF
+};
+
+/* for decoding */
+uchar d_code[256] = {
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+ 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+ 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02,
+ 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02,
+ 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+ 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+ 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04,
+ 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+ 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+ 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+ 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09,
+ 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A,
+ 0x0B, 0x0B, 0x0B, 0x0B, 0x0B, 0x0B, 0x0B, 0x0B,
+ 0x0C, 0x0C, 0x0C, 0x0C, 0x0D, 0x0D, 0x0D, 0x0D,
+ 0x0E, 0x0E, 0x0E, 0x0E, 0x0F, 0x0F, 0x0F, 0x0F,
+ 0x10, 0x10, 0x10, 0x10, 0x11, 0x11, 0x11, 0x11,
+ 0x12, 0x12, 0x12, 0x12, 0x13, 0x13, 0x13, 0x13,
+ 0x14, 0x14, 0x14, 0x14, 0x15, 0x15, 0x15, 0x15,
+ 0x16, 0x16, 0x16, 0x16, 0x17, 0x17, 0x17, 0x17,
+ 0x18, 0x18, 0x19, 0x19, 0x1A, 0x1A, 0x1B, 0x1B,
+ 0x1C, 0x1C, 0x1D, 0x1D, 0x1E, 0x1E, 0x1F, 0x1F,
+ 0x20, 0x20, 0x21, 0x21, 0x22, 0x22, 0x23, 0x23,
+ 0x24, 0x24, 0x25, 0x25, 0x26, 0x26, 0x27, 0x27,
+ 0x28, 0x28, 0x29, 0x29, 0x2A, 0x2A, 0x2B, 0x2B,
+ 0x2C, 0x2C, 0x2D, 0x2D, 0x2E, 0x2E, 0x2F, 0x2F,
+ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
+ 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F,
+};
+
+uchar d_len[256] = {
+ 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+ 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+ 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+ 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+ 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04,
+ 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04,
+ 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04,
+ 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04,
+ 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04,
+ 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04,
+ 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+ 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+ 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+ 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+ 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+ 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+ 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+ 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+ 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+ 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+ 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+ 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+ 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+ 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+ 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+ 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+};
+
+unsigned freq[T + 1]; /* frequency table */
+
+int prnt[T + N_CHAR]; /* pointers to parent nodes, except for the */
+ /* elements [T..T + N_CHAR - 1] which are used to get */
+ /* the positions of leaves corresponding to the codes. */
+
+int son[T]; /* pointers to child nodes (son[], son[] + 1) */
+
+unsigned getbuf = 0;
+uchar getlen = 0;
+
+static int GetBit(void) /* get one bit */
+{
+ unsigned i;
+
+ while (getlen <= 8) {
+ if ((int)(i = getc(infile)) < 0) i = 0;
+ getbuf |= i << (8 - getlen);
+ getlen += 8;
+ }
+ i = getbuf;
+ getbuf <<= 1;
+ getlen--;
+ return (int)((i & 0x8000) >> 15);
+}
+
+static int GetByte(void) /* get one byte */
+{
+ unsigned i;
+
+ while (getlen <= 8) {
+ if ((int)(i = getc(infile)) < 0) i = 0;
+ getbuf |= i << (8 - getlen);
+ getlen += 8;
+ }
+ i = getbuf;
+ getbuf <<= 8;
+ getlen -= 8;
+ return (int)((i & 0xff00) >> 8);
+}
+
+unsigned putbuf = 0;
+uchar putlen = 0;
+
+static void Putcode(int l, unsigned c) /* output c bits of code */
+{
+ putbuf |= c >> putlen;
+ if ((putlen += l) >= 8) {
+ if (putc(putbuf >> 8, outfile) == EOF) {
+ Error(wterr);
+ }
+ if ((putlen -= 8) >= 8) {
+ if (putc(putbuf, outfile) == EOF) {
+ Error(wterr);
+ }
+ codesize += 2;
+ putlen -= 8;
+ putbuf = c << (l - putlen);
+ } else {
+ putbuf <<= 8;
+ codesize++;
+ }
+ }
+}
+
+
+/* initialization of tree */
+
+static void StartHuff(void)
+{
+ int i, j;
+
+ for (i = 0; i < N_CHAR; i++) {
+ freq[i] = 1;
+ son[i] = i + T;
+ prnt[i + T] = i;
+ }
+ i = 0; j = N_CHAR;
+ while (j <= R) {
+ freq[j] = freq[i] + freq[i + 1];
+ son[j] = i;
+ prnt[i] = prnt[i + 1] = j;
+ i += 2; j++;
+ }
+ freq[T] = 0xffff;
+ prnt[R] = 0;
+}
+
+
+/* reconstruction of tree */
+
+static void reconst(void)
+{
+ int i, j, k;
+ unsigned f, l;
+
+ /* collect leaf nodes in the first half of the table */
+ /* and replace the freq by (freq + 1) / 2. */
+ j = 0;
+ for (i = 0; i < T; i++) {
+ if (son[i] >= T) {
+ freq[j] = (freq[i] + 1) / 2;
+ son[j] = son[i];
+ j++;
+ }
+ }
+ /* begin constructing tree by connecting sons */
+ for (i = 0, j = N_CHAR; j < T; i += 2, j++) {
+ k = i + 1;
+ f = freq[j] = freq[i] + freq[k];
+ for (k = j - 1; f < freq[k]; k--);
+ k++;
+ l = (j - k) * 2;
+ memmove(&freq[k + 1], &freq[k], l);
+ freq[k] = f;
+ memmove(&son[k + 1], &son[k], l);
+ son[k] = i;
+ }
+ /* connect prnt */
+ for (i = 0; i < T; i++) {
+ if ((k = son[i]) >= T) {
+ prnt[k] = i;
+ } else {
+ prnt[k] = prnt[k + 1] = i;
+ }
+ }
+}
+
+
+/* increment frequency of given code by one, and update tree */
+
+static void update(int c)
+{
+ int i, j, k, l;
+
+ if (freq[R] == MAX_FREQ) {
+ reconst();
+ }
+ c = prnt[c + T];
+ do {
+ k = ++freq[c];
+
+ /* if the order is disturbed, exchange nodes */
+ if ((unsigned)k > freq[l = c + 1]) {
+ while ((unsigned)k > freq[++l]);
+ l--;
+ freq[c] = freq[l];
+ freq[l] = k;
+
+ i = son[c];
+ prnt[i] = l;
+ if (i < T) prnt[i + 1] = l;
+
+ j = son[l];
+ son[l] = i;
+
+ prnt[j] = c;
+ if (j < T) prnt[j + 1] = c;
+ son[c] = j;
+
+ c = l;
+ }
+ } while ((c = prnt[c]) != 0); /* repeat up to root */
+}
+
+unsigned code, len;
+
+static void EncodeChar(unsigned c)
+{
+ unsigned i;
+ int j, k;
+
+ i = 0;
+ j = 0;
+ k = prnt[c + T];
+
+ /* travel from leaf to root */
+ do {
+ i >>= 1;
+
+ /* if node's address is odd-numbered, choose bigger brother node */
+ if (k & 1) i += 0x8000;
+
+ j++;
+ } while ((k = prnt[k]) != R);
+ Putcode(j, i);
+ code = i;
+ len = j;
+ update(c);
+}
+
+static void EncodePosition(unsigned c)
+{
+ unsigned i;
+
+ /* output upper 6 bits by table lookup */
+ i = c >> 6;
+ Putcode(p_len[i], (unsigned)p_code[i] << 8);
+
+ /* output lower 6 bits verbatim */
+ Putcode(6, (c & 0x3f) << 10);
+}
+
+static void EncodeEnd(void)
+{
+ if (putlen) {
+ if (putc(putbuf >> 8, outfile) == EOF) {
+ Error(wterr);
+ }
+ codesize++;
+ }
+}
+
+static int DecodeChar(void)
+{
+ unsigned c;
+
+ c = son[R];
+
+ /* travel from root to leaf, */
+ /* choosing the smaller child node (son[]) if the read bit is 0, */
+ /* the bigger (son[]+1} if 1 */
+ while (c < T) {
+ c += GetBit();
+ c = son[c];
+ }
+ c -= T;
+ update(c);
+ return (int)c;
+}
+
+static int DecodePosition(void)
+{
+ unsigned i, j, c;
+
+ /* recover upper 6 bits from table */
+ i = GetByte();
+ c = (unsigned)d_code[i] << 6;
+ j = d_len[i];
+
+ /* read lower 6 bits verbatim */
+ j -= 2;
+ while (j--) {
+ i = (i << 1) + GetBit();
+ }
+ return (int)(c | (i & 0x3f));
+}
+
+/* compression */
+
+static void Encode(void) /* compression */
+{
+ int i, c, len, r, s, last_match_length;
+
+ fseek(infile, 0L, 2);
+ textsize = ftell(infile);
+ fputc((int)((textsize & 0xff)),outfile);
+ fputc((int)((textsize & 0xff00) >> 8),outfile);
+ fputc((int)((textsize & 0xff0000L) >> 16),outfile);
+ fputc((int)((textsize & 0xff000000L) >> 24),outfile);
+ if (ferror(outfile))
+ Error(wterr); /* output size of text */
+ if (textsize == 0)
+ return;
+ rewind(infile);
+ textsize = 0; /* rewind and re-read */
+ StartHuff();
+ InitTree();
+ s = 0;
+ r = N - F;
+ for (i = s; i < r; i++)
+ text_buf[i] = 0x20;
+ for (len = 0; len < F && (c = getc(infile)) != EOF; len++)
+ text_buf[r + len] = (unsigned char)c;
+ textsize = len;
+ for (i = 1; i <= F; i++)
+ InsertNode(r - i);
+ InsertNode(r);
+ do {
+ if (match_length > len)
+ match_length = len;
+ if (match_length <= THRESHOLD) {
+ match_length = 1;
+ EncodeChar(text_buf[r]);
+ } else {
+ EncodeChar(255 - THRESHOLD + match_length);
+ EncodePosition(match_position);
+ }
+ last_match_length = match_length;
+ for (i = 0; i < last_match_length &&
+ (c = getc(infile)) != EOF; i++) {
+ DeleteNode(s);
+ text_buf[s] = (unsigned char)c;
+ if (s < F - 1)
+ text_buf[s + N] = (unsigned char)c;
+ s = (s + 1) & (N - 1);
+ r = (r + 1) & (N - 1);
+ InsertNode(r);
+ }
+ if ((textsize += i) > printcount) {
+ printf("%12ld\r", textsize);
+ printcount += 1024;
+ }
+ while (i++ < last_match_length) {
+ DeleteNode(s);
+ s = (s + 1) & (N - 1);
+ r = (r + 1) & (N - 1);
+ if (--len) InsertNode(r);
+ }
+ } while (len > 0);
+ EncodeEnd();
+ printf("In : %ld bytes\n", textsize);
+ printf("Out: %ld bytes\n", codesize);
+ printf("Out/In: %.3f\n", 1.0 * codesize / textsize);
+}
+
+static void Decode(void) /* recover */
+{
+ int i, j, k, r, c;
+ unsigned long int count;
+
+ textsize = (fgetc(infile));
+ textsize |= (fgetc(infile) << 8);
+ textsize |= (fgetc(infile) << 16);
+ textsize |= (fgetc(infile) << 24);
+ if (ferror(infile))
+ Error("Can't read"); /* read size of text */
+ if (textsize == 0)
+ return;
+ StartHuff();
+ for (i = 0; i < N - F; i++)
+ text_buf[i] = 0x20;
+ r = N - F;
+ for (count = 0; count < textsize; ) {
+ c = DecodeChar();
+ if (c < 256) {
+ if (putc(c, outfile) == EOF) {
+ Error(wterr);
+ }
+ text_buf[r++] = (unsigned char)c;
+ r &= (N - 1);
+ count++;
+ } else {
+ i = (r - DecodePosition() - 1) & (N - 1);
+ j = c - 255 + THRESHOLD;
+ for (k = 0; k < j; k++) {
+ c = text_buf[(i + k) & (N - 1)];
+ if (putc(c, outfile) == EOF) {
+ Error(wterr);
+ }
+ text_buf[r++] = (unsigned char)c;
+ r &= (N - 1);
+ count++;
+ }
+ }
+ if (count > printcount) {
+ printf("%12ld\r", count);
+ printcount += 1024;
+ }
+ }
+ printf("%12ld\n", count);
+}
+
+int main(int argc, char *argv[])
+{
+ char *s;
+
+ if (argc != 4) {
+ printf("'lzhuf e file1 file2' encodes file1 into file2.\n"
+ "'lzhuf 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;
+ }
+ if (toupper(*argv[1]) == 'E')
+ Encode();
+ else
+ Decode();
+ fclose(infile);
+ fclose(outfile);
+ return EXIT_SUCCESS;
+}