ref: 520d698c3e9ec8f76923965481aa15862f9f3c81
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); }