Category : C Source Code
Archive   : SMALLC.ZIP
Filename : FORMAT1.C

/* Text formatter: main program
*
* text formatter transcribed from the book
* Software Tools by Kernighan and Plauger
*
* Source: format1.c
* Version: Dec. 31, 1980.
*/




/* text formatter main program (final version) */


main()
{
char inbuf[INSIZE];
init();
while (getlin(inbuf)!=EOF) {
if (inbuf[0]=='.') {
command(inbuf);
}
else {
text(inbuf);
}
}
if (lineno>0) {
space(HUGE);
}
closeout(); /* close output file */
}


/* initialize all variables.
* open files.
*/


init()
{
/* sign on */
puts("Welcome to format version: April 5, 1981.");
/* common /cparam/ */
fill=YES;
lsval=1;
inval=0;
rmval=PAGEWIDTH;
tival=0;
ceval=0;
ulval=0;
/* common /cpage/ */
curpag=0;
newpag=1;
lineno=0;
plval=PAGELEN;
m1val=2;
m2val=2;
m3val=2;
m4val=2;
bottom=plval-m3val-m4val; /* invariant */
header[0]=NEWLINE;
header[1]=EOS;
footer[0]=NEWLINE;
footer[1]=EOS;
/* common /cout/ */
outp=0;
outw=0;
outwds=0;
/* spread() */
dir=0;
/* I/O routines */
openout();
ineof=YES; /* force openin() */
}


/* perform formatting command */


command(buf) char *buf;
{
int argtyp;
int val;
int spval;
val=getval(buf,&argtyp);
if (lookup(buf,"bp")) {
if (lineno>0) {
space(HUGE);
}
set(&curpag,val,argtyp,curpag+1,-HUGE,HUGE);
newpag=curpag;
}
else if (lookup(buf,"br")) {
brk();
}
else if (lookup(buf,"ce")) {
brk();
set(&ceval,val,argtyp,1,0,HUGE);
}
else if (lookup(buf,"fi")) {
brk();
fill=YES;
}
else if (lookup(buf,"fo")) {
gettl(buf,footer);
}
else if (lookup(buf,"he")) {
gettl(buf,header);
}
else if (lookup(buf,"in")) {
set(&inval,val,argtyp,0,0,rmval-1);
tival=inval;
}
else if (lookup(buf,"ls")) {
set(&lsval,val,argtyp,1,1,HUGE);
}
else if (lookup(buf,"nf")) {
brk();
fill=NO;
}
else if (lookup(buf,"pl")) {
set(&plval,val,argtyp,PAGELEN,
m1val+m2val+m3val+m4val+1,HUGE);
bottom=plval-m3val-m4val;
}
else if (lookup(buf,"rm")) {
set(&rmval,val,argtyp,PAGEWIDTH,
tival+1,HUGE);
}
else if (lookup(buf,"sp")) {
set(&spval,val,argtyp,1,0,HUGE);
space(spval);
}
else if (lookup(buf,"ti")) {
brk();
set(&tival,val,argtyp,0,0,rmval);
}
else if (lookup(buf,"ul")) {
set(&ulval,val,argtyp,0,1,HUGE);
}
else {
return; /* ignore unknown commands */
}
}


/* lookup routines for commands.
* return true if buf starts with string.
*/


lookup(buf,string) char *buf, *string;
{
return( (buf[1]==string[0]) *
(buf[2]==string[1]) );
}


/* evaluate optional numeric argument */


getval(buf,argtyp) char *buf; int *argtyp;
{
int i;
/* skip command name */
i=1;
while ( (buf[i]!=' ') *
(buf[i]!=TAB) *
(buf[i]!=NEWLINE) ) {
i++;
}
/* find argument */
while ( (buf[i]==' ') +
(buf[i]==TAB) ) {
i++;
}
*argtyp=buf[i];
if ( (*argtyp=='+') +
(*argtyp=='-') ) {
i++;
}
return(ctoi(buf,i));
}


/* set parameter and check range */


set(param,val,argtyp,defval,minval,maxval)
int *param,val,argtyp,defval,minval,maxval;
{
if (argtyp==NEWLINE) {
*param=defval;
}
else if (argtyp=='+') {
*param=*param+val;
}
else if (argtyp=='-') {
*param=*param-val;
}
else {
*param=val;
}
*param=min(*param,maxval);
*param=max(*param,minval);
}