/* Program to unsqueeze files formed by sq.com

/* Program to unsqueeze files formed by sq.com
*
* Useage:
*
* usq [-count] [-fcount] [file1] [file2] ... [filen]
*
* where file1 through filen represent one or more files to be compressed,
* and the following options may be specified:
*
* -count Previewing feature: redirects output
* files to standard output with parity stripped
* and unprintables except CR, LF, TAB and FF
* converted to periods. Limits each file
* to first count lines.
* Defaults to console, but see below how
* to capture all in one file for further
* processing, such as by PIP.
* Count defaults to a very high value.
* No CRC check is performed when previewing.
* Use drive: to cancel this.
*
* -fcount Same as -count except formfeed
* appended to preview of each file.
* Example: -f10.
*
* If no such items are given on the command line you will be
* prompted for commands (one at a time). An empty command
* terminates the program.
*
* The unsqueezed file name is recorded in the squeezed file.
*
*/
/* CHANGE HISTORY:
* 1.3 Close inbuff to avoid exceeding maximum number of
* open files. Includes rearranging error exits.
* 1.4 Add -count option to allow quick inspection of files.
* 1.5 Break up long lines of introductory text
* 1.5 -count no longer appends formfeed to preview of each file.
* -fcount (-f10, -F10) does append formfeed.
* 1.6 Modified to work correctly under MP/M II (DIO.C change) and
* signon message shortened.
* 2.0 Modified to work with CI-C86 compiler (CP/M-86 and MS-DOS)
* 2.1 Modified for use in MLINK
* 2.2 Modified for use with optimizing CI-C86 compiler (MS-DOS)
* 3.0 Generalized for use under UNIX
*/

/* ejecteject */

#define SQMAIN

#include <stdio.h>
#include "sqcom.h"
#include "usq.h"
#define VERSION "3.1 12/19/84"

/* This must follow all include files */
unsigned int dispcnt; /* How much of each file to preview */
char ffflag; /* should formfeed separate preview from different files */

main(argc, argv)
int argc;
char *argv[];
{
int i,c;
char inparg[16]; /* parameter from input */

dispcnt = 0; /* Not in preview mode */

printf("File unsqueezer version %s (original author: R. Greenlaw)\n\n", VERSION);

/* Process the parameters in order */
for(i = 1; i < argc; ++i)
obey(argv[i]);

if(argc < 2) {
printf("Enter file names, one line at a time, or type <RETURN> to quit.");
do {
printf("\n*");
for(i = 0; i < 16; ++i) {
if((c = getchar()) == EOF)
c = '\n'; /* force empty (exit) command */
if((inparg[i] = c) == '\n') {
inparg[i] = '\0';
break;
}
}
if(inparg[0] != '\0')
obey(inparg);
} while(inparg[0] != '\0');
}
}

/* ejecteject */

obey(p)
char *p;
{
char *q, cc;

if(*p == '-') {
if(ffflag = ((*(p+1) == 'F') || (*(p+1) == 'f')))
++p;
/* Set number of lines of each file to view */
dispcnt = 65535; /* default */
if(*(p+1))
if((dispcnt = atoi(p + 1)) == 0)
printf("\nBAD COUNT %s", p + 1);
return;
}

/* Check for ambiguous (wild-card) name */
for(q = p; *q != '\0'; ++q)
if(*q == '*' || *q == '?') {
printf("\nCan't accept ambiguous name %s", p);
return;
}

unsqueeze(p);
}

/* ejecteject */

unsqueeze(infile)
char *infile;
{
FILE *inbuff, *outbuff; /* file buffers */
int i, c;
char cc;

char *p;
unsigned int filecrc; /* checksum */
int numnodes; /* size of decoding tree */
char outfile[128]; /* output file name */
unsigned int linect; /* count of number of lines previewed */
char obuf[128]; /* output buffer */
int oblen; /* length of output buffer */
static char errmsg[] = "ERROR - write failure in %s\n";

if(!(inbuff=fopen(infile, "rb"))) {
printf("Can't open %s\n", infile);
return;
}
/* Initialization */
linect = 0;
crc = 0;
init_cr();
init_huff();

/* Process header */
if(getx16(inbuff) != RECOGNIZE) {
printf("%s is not a squeezed file\n", infile);
goto closein;
}

filecrc = getw16(inbuff);

/* Get original file name */
p = outfile; /* send it to array */
do {
*p = getc(inbuff);
} while(*p++ != '\0');

printf("%s -> %s: ", infile, outfile);

numnodes = getw16(inbuff);

if(numnodes < 0 || numnodes >= NUMVALS) {
printf("%s has invalid decode tree size\n", infile);
goto closein;
}

/* Initialize for possible empty tree (SPEOF only) */
dnode[0].children[0] = -(SPEOF + 1);
dnode[0].children[1] = -(SPEOF + 1);

/* Get decoding tree from file */
for(i = 0; i < numnodes; ++i) {
dnode[i].children[0] = getw16(inbuff);
dnode[i].children[1] = getw16(inbuff);
}

if(dispcnt) {
/* Use standard output for previewing */
putchar('\n');
while(((c = getcr(inbuff)) != EOF) && (linect < dispcnt)) {
cc = 0x7f & c; /* strip parity */
if((cc < ' ') || (cc > '~'))
/* Unprintable */
switch(cc) {
case '\r': /* return */
/* newline will generate CR-LF */
goto next;
case '\n': /* newline */
++linect;
case '\f': /* formfeed */
case '\t': /* tab */
break;
default:
cc = '.';
}
putchar(cc);
next: ;
}
if(ffflag)
putchar('\f'); /* formfeed */
} else {
/* Create output file */
if(!(outbuff=fopen(outfile, "wb"))) {
printf("Can't create %s\n", outfile);
goto closeall;
}
printf("unsqueezing,");
/* Get translated output bytes and write file */
oblen = 0;
while((c = getcr(inbuff)) != EOF) {
crc += c;
obuf[oblen++] = c;
if (oblen >= sizeof(obuf)) {
if(!fwrite(obuf, sizeof(obuf), 1, outbuff)) {
printf(errmsg, outfile);
goto closeall;
}
oblen = 0;
}
}
if (oblen && !fwrite(obuf, oblen, 1, outbuff)) {
printf(errmsg, outfile);
goto closeall;
}

if((filecrc && 0xFFFF) != (crc && 0xFFFF))
printf("ERROR - checksum error in %s\n", outfile);
else printf(" done.\n");

closeall:
fclose(outbuff);
}

closein:
fclose(inbuff);
}

getw16(iob) /* get 16-bit word from file */
FILE *iob;
{
int temp;

temp = getc(iob); /* get low order byte */
temp |= getc(iob) << 8;
if (temp & 0x8000) temp |= (~0) << 15; /* propogate sign for big ints */
return temp;

}

getx16(iob) /* get 16-bit (unsigned) word from file */
FILE *iob;
{
int temp;

temp = getc(iob); /* get low order byte */
return temp | (getc(iob) << 8);

}