ref: b0377e84cf31c48afed765c433abe7eebb4135a5
dir: /sys/src/cmd/bc.y/
%{
#include <u.h>
#include <libc.h>
#include <bio.h>
#define bsp_max 5000
Biobuf *in;
Biobuf bstdin;
Biobuf bstdout;
char cary[1000];
char* cp = { cary };
char string[1000];
char* str = { string };
int crs = 128;
int rcrs = 128; /* reset crs */
int bindx = 0;
int lev = 0;
int ln;
char* ttp;
char* ss = "";
int bstack[10] = { 0 };
char* numb[15] =
{
" 0", " 1", " 2", " 3", " 4", " 5",
" 6", " 7", " 8", " 9", " 10", " 11",
" 12", " 13", " 14"
};
char* pre;
char* post;
long peekc = -1;
int sargc;
int ifile;
char** sargv;
char *funtab[] =
{
"<1>","<2>","<3>","<4>","<5>",
"<6>","<7>","<8>","<9>","<10>",
"<11>","<12>","<13>","<14>","<15>",
"<16>","<17>","<18>","<19>","<20>",
"<21>","<22>","<23>","<24>","<25>",
"<26>"
};
char *atab[] =
{
"<221>","<222>","<223>","<224>","<225>",
"<226>","<227>","<228>","<229>","<230>",
"<231>","<232>","<233>","<234>","<235>",
"<236>","<237>","<238>","<239>","<240>",
"<241>","<242>","<243>","<244>","<245>",
"<246>"
};
char* letr[26] =
{
"a","b","c","d","e","f","g","h","i","j",
"k","l","m","n","o","p","q","r","s","t",
"u","v","w","x","y","z"
};
char* dot = { "." };
char* bspace[bsp_max];
char** bsp_nxt = bspace;
int bdebug = 0;
int lflag;
int cflag;
int sflag;
char* bundle(int, ...);
void conout(char*, char*);
int cpeek(int, int, int);
int getch(void);
char* geta(char*);
char* getf(char*);
void getout(void);
void output(char*);
void pp(char*);
void routput(char*);
void tp(char*);
void yyerror(char*, ...);
int yyparse(void);
typedef void* pointer;
#pragma varargck type "lx" pointer
%}
%union
{
char* cptr;
int cc;
}
%type <cptr> pstat stat stat1 def slist dlets e ase nase
%type <cptr> slist re fprefix cargs eora cons constant lora
%type <cptr> crs
%token <cptr> LETTER EQOP _AUTO DOT
%token <cc> DIGIT SQRT LENGTH _IF FFF EQ
%token <cc> _PRINT _WHILE _FOR NE LE GE INCR DECR
%token <cc> _RETURN _BREAK _DEFINE BASE OBASE SCALE
%token <cc> QSTR ERROR
%right '=' EQOP
%left '+' '-'
%left '*' '/' '%'
%right '^'
%left UMINUS
%%
start:
start stuff
| stuff
stuff:
pstat tail
{
output($1);
}
| def dargs ')' '{' dlist slist '}'
{
ttp = bundle(6, pre, $6, post , "0", numb[lev], "Q");
conout(ttp, (char*)$1);
rcrs = crs;
output("");
lev = bindx = 0;
}
dlist:
tail
| dlist _AUTO dlets tail
stat:
stat1
| nase
{
if(sflag)
bundle(2, $1, "s.");
}
pstat:
stat1
{
if(sflag)
bundle(2, $1, "0");
}
| nase
{
if(!sflag)
bundle(2, $1, "ps.");
}
stat1:
{
bundle(1, "");
}
| ase
{
bundle(2, $1, "s.");
}
| SCALE '=' e
{
bundle(2, $3, "k");
}
| SCALE EQOP e
{
bundle(4, "K", $3, $2, "k");
}
| BASE '=' e
{
bundle(2, $3, "i");
}
| BASE EQOP e
{
bundle(4, "I", $3, $2, "i");
}
| OBASE '=' e
{
bundle(2, $3, "o");
}
| OBASE EQOP e
{
bundle(4, "O", $3, $2, "o");
}
| QSTR
{
bundle(3, "[", $1, "]P");
}
| _BREAK
{
bundle(2, numb[lev-bstack[bindx-1]], "Q");
}
| _PRINT e
{
bundle(2, $2, "ps.");
}
| _RETURN e
{
bundle(4, $2, post, numb[lev], "Q");
}
| _RETURN
{
bundle(4, "0", post, numb[lev], "Q");
}
| '{' slist '}'
{
$$ = $2;
}
| FFF
{
bundle(1, "fY");
}
| _IF crs BLEV '(' re ')' stat
{
conout($7, $2);
bundle(3, $5, $2, " ");
}
| _WHILE crs '(' re ')' stat BLEV
{
bundle(3, $6, $4, $2);
conout($$, $2);
bundle(3, $4, $2, " ");
}
| fprefix crs re ';' e ')' stat BLEV
{
bundle(5, $7, $5, "s.", $3, $2);
conout($$, $2);
bundle(5, $1, "s.", $3, $2, " ");
}
| '~' LETTER '=' e
{
bundle(3, $4, "S", $2);
}
fprefix:
_FOR '(' e ';'
{
$$ = $3;
}
BLEV:
=
{
--bindx;
}
slist:
stat
| slist tail stat
{
bundle(2, $1, $3);
}
tail:
'\n'
{
ln++;
}
| ';'
re:
e EQ e
{
$$ = bundle(3, $1, $3, "=");
}
| e '<' e
{
bundle(3, $1, $3, ">");
}
| e '>' e
{
bundle(3, $1, $3, "<");
}
| e NE e
{
bundle(3, $1, $3, "!=");
}
| e GE e
{
bundle(3, $1, $3, "!>");
}
| e LE e
{
bundle(3, $1, $3, "!<");
}
| e
{
bundle(2, $1, " 0!=");
}
nase:
'(' e ')'
{
$$ = $2;
}
| cons
{
bundle(3, " ", $1, " ");
}
| DOT cons
{
bundle(3, " .", $2, " ");
}
| cons DOT cons
{
bundle(5, " ", $1, ".", $3, " ");
}
| cons DOT
{
bundle(4, " ", $1, ".", " ");
}
| DOT
{
$<cptr>$ = "l.";
}
| LETTER '[' e ']'
{
bundle(3, $3, ";", geta($1));
}
| LETTER INCR
{
bundle(4, "l", $1, "d1+s", $1);
}
| INCR LETTER
{
bundle(4, "l", $2, "1+ds", $2);
}
| DECR LETTER
{
bundle(4, "l", $2, "1-ds", $2);
}
| LETTER DECR
{
bundle(4, "l", $1, "d1-s", $1);
}
| LETTER '[' e ']' INCR
{
bundle(7, $3, ";", geta($1), "d1+" ,$3, ":" ,geta($1));
}
| INCR LETTER '[' e ']'
{
bundle(7, $4, ";", geta($2), "1+d", $4, ":", geta($2));
}
| LETTER '[' e ']' DECR
{
bundle(7, $3, ";", geta($1), "d1-", $3, ":", geta($1));
}
| DECR LETTER '[' e ']'
{
bundle(7, $4, ";", geta($2), "1-d", $4, ":" ,geta($2));
}
| SCALE INCR
{
bundle(1, "Kd1+k");
}
| INCR SCALE
{
bundle(1, "K1+dk");
}
| SCALE DECR
{
bundle(1, "Kd1-k");
}
| DECR SCALE
{
bundle(1, "K1-dk");
}
| BASE INCR
{
bundle(1, "Id1+i");
}
| INCR BASE
{
bundle(1, "I1+di");
}
| BASE DECR
{
bundle(1, "Id1-i");
}
| DECR BASE
{
bundle(1, "I1-di");
}
| OBASE INCR
{
bundle(1, "Od1+o");
}
| INCR OBASE
{
bundle(1, "O1+do");
}
| OBASE DECR
{
bundle(1, "Od1-o");
}
| DECR OBASE
{
bundle(1, "O1-do");
}
| LETTER '(' cargs ')'
{
bundle(4, $3, "l", getf($1), "x");
}
| LETTER '(' ')'
{
bundle(3, "l", getf($1), "x");
}
| LETTER = {
bundle(2, "l", $1);
}
| LENGTH '(' e ')'
{
bundle(2, $3, "Z");
}
| SCALE '(' e ')'
{
bundle(2, $3, "X");
}
| '?'
{
bundle(1, "?");
}
| SQRT '(' e ')'
{
bundle(2, $3, "v");
}
| '~' LETTER
{
bundle(2, "L", $2);
}
| SCALE
{
bundle(1, "K");
}
| BASE
{
bundle(1, "I");
}
| OBASE
{
bundle(1, "O");
}
| '-' e
{
bundle(3, " 0", $2, "-");
}
| e '+' e
{
bundle(3, $1, $3, "+");
}
| e '-' e
{
bundle(3, $1, $3, "-");
}
| e '*' e
{
bundle(3, $1, $3, "*");
}
| e '/' e
{
bundle(3, $1, $3, "/");
}
| e '%' e
{
bundle(3, $1, $3, "%%");
}
| e '^' e
{
bundle(3, $1, $3, "^");
}
ase:
LETTER '=' e
{
bundle(3, $3, "ds", $1);
}
| LETTER '[' e ']' '=' e
{
bundle(5, $6, "d", $3, ":", geta($1));
}
| LETTER EQOP e
{
bundle(6, "l", $1, $3, $2, "ds", $1);
}
| LETTER '[' e ']' EQOP e
{
bundle(9, $3, ";", geta($1), $6, $5, "d", $3, ":", geta($1));
}
e:
ase
| nase
cargs:
eora
| cargs ',' eora
{
bundle(2, $1, $3);
}
eora:
e
| LETTER '[' ']'
{
bundle(2, "l", geta($1));
}
cons:
constant
{
*cp++ = 0;
}
constant:
'_'
{
$<cptr>$ = cp;
*cp++ = '_';
}
| DIGIT
{
$<cptr>$ = cp;
*cp++ = $1;
}
| constant DIGIT
{
*cp++ = $2;
}
crs:
=
{
$$ = cp;
*cp++ = '<';
*cp++ = crs/100+'0';
*cp++ = (crs%100)/10+'0';
*cp++ = crs%10+'0';
*cp++ = '>';
*cp++ = '\0';
if(crs++ >= 220) {
yyerror("program too big");
getout();
}
bstack[bindx++] = lev++;
}
def:
_DEFINE LETTER '('
{
$$ = getf($2);
pre = (char*)"";
post = (char*)"";
lev = 1;
bindx = 0;
bstack[bindx] = 0;
}
dargs:
| lora
{
pp((char*)$1);
}
| dargs ',' lora
{
pp((char*)$3);
}
dlets:
lora
{
tp((char*)$1);
}
| dlets ',' lora
{
tp((char*)$3);
}
lora:
LETTER
{
$<cptr>$=$1;
}
| LETTER '[' ']'
{
$$ = geta($1);
}
%%
int
yylex(void)
{
int c, ch;
restart:
c = getch();
peekc = -1;
while(c == ' ' || c == '\t')
c = getch();
if(c == '\\') {
getch();
goto restart;
}
if(c >= 'a' && c <= 'z') {
/* look ahead to look for reserved words */
peekc = getch();
if(peekc >= 'a' && peekc <= 'z') { /* must be reserved word */
if(c=='p' && peekc=='r') {
c = _PRINT;
goto skip;
}
if(c=='i' && peekc=='f') {
c = _IF;
goto skip;
}
if(c=='w' && peekc=='h') {
c = _WHILE;
goto skip;
}
if(c=='f' && peekc=='o') {
c = _FOR;
goto skip;
}
if(c=='s' && peekc=='q') {
c = SQRT;
goto skip;
}
if(c=='r' && peekc=='e') {
c = _RETURN;
goto skip;
}
if(c=='b' && peekc=='r') {
c = _BREAK;
goto skip;
}
if(c=='d' && peekc=='e') {
c = _DEFINE;
goto skip;
}
if(c=='s' && peekc=='c') {
c = SCALE;
goto skip;
}
if(c=='b' && peekc=='a') {
c = BASE;
goto skip;
}
if(c=='i' && peekc=='b') {
c = BASE;
goto skip;
}
if(c=='o' && peekc=='b') {
c = OBASE;
goto skip;
}
if(c=='d' && peekc=='i') {
c = FFF;
goto skip;
}
if(c=='a' && peekc=='u') {
c = _AUTO;
goto skip;
}
if(c=='l' && peekc=='e') {
c = LENGTH;
goto skip;
}
if(c=='q' && peekc=='u')
getout();
/* could not be found */
return ERROR;
skip: /* skip over rest of word */
peekc = -1;
for(;;) {
ch = getch();
if(ch < 'a' || ch > 'z')
break;
}
peekc = ch;
return c;
}
/* usual case; just one single letter */
yylval.cptr = letr[c-'a'];
return LETTER;
}
if((c >= '0' && c <= '9') || (c >= 'A' && c <= 'F')) {
yylval.cc = c;
return DIGIT;
}
switch(c) {
case '.':
return DOT;
case '*':
yylval.cptr = "*";
return cpeek('=', EQOP, c);
case '%':
yylval.cptr = "%%";
return cpeek('=', EQOP, c);
case '^':
yylval.cptr = "^";
return cpeek('=', EQOP, c);
case '+':
ch = cpeek('=', EQOP, c);
if(ch == EQOP) {
yylval.cptr = "+";
return ch;
}
return cpeek('+', INCR, c);
case '-':
ch = cpeek('=', EQOP, c);
if(ch == EQOP) {
yylval.cptr = "-";
return ch;
}
return cpeek('-', DECR, c);
case '=':
return cpeek('=', EQ, '=');
case '<':
return cpeek('=', LE, '<');
case '>':
return cpeek('=', GE, '>');
case '!':
return cpeek('=', NE, '!');
case '/':
ch = cpeek('=', EQOP, c);
if(ch == EQOP) {
yylval.cptr = "/";
return ch;
}
if(peekc == '*') {
peekc = -1;
for(;;) {
ch = getch();
if(ch == '*') {
peekc = getch();
if(peekc == '/') {
peekc = -1;
goto restart;
}
}
}
}
return c;
case '"':
yylval.cptr = str;
while((c=getch()) != '"'){
*str++ = c;
if(str >= &string[999]){
yyerror("string space exceeded");
getout();
}
}
*str++ = 0;
return QSTR;
default:
return c;
}
}
int
cpeek(int c, int yes, int no)
{
peekc = getch();
if(peekc == c) {
peekc = -1;
return yes;
}
return no;
}
int
getch(void)
{
long ch;
loop:
ch = peekc;
if(ch < 0){
if(in == 0)
ch = -1;
else
ch = Bgetc(in);
}
peekc = -1;
if(ch >= 0)
return ch;
ifile++;
if(ifile > sargc) {
if(ifile >= sargc+2)
getout();
in = &bstdin;
Binit(in, 0, OREAD);
ln = 0;
goto loop;
}
if(in)
Bterm(in);
if((in = Bopen(sargv[ifile], OREAD)) != 0){
ln = 0;
ss = sargv[ifile];
goto loop;
}
yyerror("cannot open input file");
return 0; /* shut up ken */
}
char*
bundle(int a, ...)
{
int i;
char **q;
va_list arg;
i = a;
va_start(arg, a);
q = bsp_nxt;
if(bdebug)
fprint(2, "bundle %d elements at %lx\n", i, q);
while(i-- > 0) {
if(bsp_nxt >= &bspace[bsp_max])
yyerror("bundling space exceeded");
*bsp_nxt++ = va_arg(arg, char*);
}
*bsp_nxt++ = 0;
va_end(arg);
yyval.cptr = (char*)q;
return (char*)q;
}
void
routput(char *p)
{
char **pp;
if(bdebug)
fprint(2, "routput(%lx)\n", p);
if((char**)p >= &bspace[0] && (char**)p < &bspace[bsp_max]) {
/* part of a bundle */
pp = (char**)p;
while(*pp != 0)
routput(*pp++);
} else
Bprint(&bstdout, p); /* character string */
}
void
output(char *p)
{
routput(p);
bsp_nxt = &bspace[0];
Bprint(&bstdout, "\n");
Bflush(&bstdout);
cp = cary;
crs = rcrs;
}
void
conout(char *p, char *s)
{
Bprint(&bstdout, "[");
routput(p);
Bprint(&bstdout, "]s%s\n", s);
Bflush(&bstdout);
lev--;
}
void
yyerror(char *s, ...)
{
if(ifile > sargc)
ss = "stdin";
Bprint(&bstdout, "c[%s:%d %s]pc\n", ss, ln+1, s);
Bflush(&bstdout);
cp = cary;
crs = rcrs;
bindx = 0;
lev = 0;
bsp_nxt = &bspace[0];
}
void
pp(char *s)
{
/* puts the relevant stuff on pre and post for the letter s */
bundle(3, "S", s, pre);
pre = yyval.cptr;
bundle(4, post, "L", s, "s.");
post = yyval.cptr;
}
void
tp(char *s)
{
/* same as pp, but for temps */
bundle(3, "0S", s, pre);
pre = yyval.cptr;
bundle(4, post, "L", s, "s.");
post = yyval.cptr;
}
void
yyinit(int argc, char **argv)
{
Binit(&bstdout, 1, OWRITE);
sargv = argv;
sargc = argc - 1;
if(sargc == 0) {
in = &bstdin;
Binit(in, 0, OREAD);
} else if((in = Bopen(sargv[1], OREAD)) == 0)
yyerror("cannot open input file");
ifile = 1;
ln = 0;
ss = sargv[1];
}
void
getout(void)
{
Bprint(&bstdout, "q");
Bflush(&bstdout);
exits(0);
}
char*
getf(char *p)
{
return funtab[*p - 'a'];
}
char*
geta(char *p)
{
return atab[*p - 'a'];
}
void
main(int argc, char **argv)
{
int p[2];
while(argc > 1 && *argv[1] == '-') {
switch(argv[1][1]) {
case 'd':
bdebug++;
break;
case 'c':
cflag++;
break;
case 'l':
lflag++;
break;
case 's':
sflag++;
break;
default:
fprint(2, "usage: bc [-cdls] [file ...]\n");
exits("usage");
}
argc--;
argv++;
}
if(lflag) {
argv--;
argc++;
argv[1] = "/sys/lib/bclib";
}
if(cflag) {
yyinit(argc, argv);
for(;;)
yyparse();
/* not reached */
}
pipe(p);
if(fork() == 0) {
dup(p[1], 1);
close(p[0]);
close(p[1]);
yyinit(argc, argv);
for(;;)
yyparse();
}
dup(p[0], 0);
close(p[0]);
close(p[1]);
execl("/bin/dc", "dc", nil);
}