📄 bis1_tab.c
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}
yystacksize *= 2;
if (yystacksize > YYMAXDEPTH)
yystacksize = YYMAXDEPTH;
yyss = (short *) malloc (yystacksize * sizeof (*yyssp));
__yy_memcpy ((char *)yyss1, (char *)yyss, size * sizeof (*yyssp));
yyvs = (YYSTYPE *) malloc (yystacksize * sizeof (*yyvsp));
__yy_memcpy ((char *)yyvs1, (char *)yyvs, size * sizeof (*yyvsp));
#ifdef YYLSP_NEEDED
yyls = (YYLTYPE *) malloc (yystacksize * sizeof (*yylsp));
__yy_memcpy ((char *)yyls1, (char *)yyls, size * sizeof (*yylsp));
#endif
#endif /* no yyoverflow */
yyssp = yyss + size - 1;
yyvsp = yyvs + size - 1;
#ifdef YYLSP_NEEDED
yylsp = yyls + size - 1;
#endif
#if YYDEBUG != 0
if (yydebug)
fprintf(stderr, "Stack size increased to %d\n", yystacksize);
#endif
if (yyssp >= yyss + yystacksize - 1)
YYABORT;
}
#if YYDEBUG != 0
if (yydebug)
fprintf(stderr, "Entering state %d\n", yystate);
#endif
goto yybackup;
yybackup:
/* Do appropriate processing given the current state. */
/* Read a lookahead token if we need one and don't already have one. */
/* yyresume: */
/* First try to decide what to do without reference to lookahead token. */
yyn = yypact[yystate];
if (yyn == YYFLAG)
goto yydefault;
/* Not known => get a lookahead token if don't already have one. */
/* yychar is either YYEMPTY or YYEOF
or a valid token in external form. */
if (yychar == YYEMPTY)
{
#if YYDEBUG != 0
if (yydebug)
fprintf(stderr, "Reading a token: ");
#endif
yychar = YYLEX;
}
/* Convert token to internal form (in yychar1) for indexing tables with */
if (yychar <= 0) /* This means end of input. */
{
yychar1 = 0;
yychar = YYEOF; /* Don't call YYLEX any more */
#if YYDEBUG != 0
if (yydebug)
fprintf(stderr, "Now at end of input.\n");
#endif
}
else
{
yychar1 = YYTRANSLATE(yychar);
#if YYDEBUG != 0
if (yydebug)
{
fprintf (stderr, "Next token is %d (%s", yychar, yytname[yychar1]);
/* Give the individual parser a way to print the precise meaning
of a token, for further debugging info. */
#ifdef YYPRINT
YYPRINT (stderr, yychar, yylval);
#endif
fprintf (stderr, ")\n");
}
#endif
}
yyn += yychar1;
if (yyn < 0 || yyn > YYLAST || yycheck[yyn] != yychar1)
goto yydefault;
yyn = yytable[yyn];
/* yyn is what to do for this token type in this state.
Negative => reduce, -yyn is rule number.
Positive => shift, yyn is new state.
New state is final state => don't bother to shift,
just return success.
0, or most negative number => error. */
if (yyn < 0)
{
if (yyn == YYFLAG)
goto yyerrlab;
yyn = -yyn;
goto yyreduce;
}
else if (yyn == 0)
goto yyerrlab;
if (yyn == YYFINAL)
YYACCEPT;
/* Shift the lookahead token. */
#if YYDEBUG != 0
if (yydebug)
fprintf(stderr, "Shifting token %d (%s), ", yychar, yytname[yychar1]);
#endif
/* Discard the token being shifted unless it is eof. */
if (yychar != YYEOF)
yychar = YYEMPTY;
*++yyvsp = yylval;
#ifdef YYLSP_NEEDED
*++yylsp = yylloc;
#endif
/* count tokens shifted since error; after three, turn off error status. */
if (yyerrstatus) yyerrstatus--;
yystate = yyn;
goto yynewstate;
/* Do the default action for the current state. */
yydefault:
yyn = yydefact[yystate];
if (yyn == 0)
goto yyerrlab;
/* Do a reduction. yyn is the number of a rule to reduce with. */
yyreduce:
yylen = yyr2[yyn];
if (yylen > 0)
yyval = yyvsp[1-yylen]; /* implement default value of the action */
#if YYDEBUG != 0
if (yydebug)
{
int i;
fprintf (stderr, "Reducing via rule %d (line %d), ",
yyn, yyrline[yyn]);
/* Print the symbols being reduced, and their result. */
for (i = yyprhs[yyn]; yyrhs[i] > 0; i++)
fprintf (stderr, "%s ", yytname[yyrhs[i]]);
fprintf (stderr, " -> %s\n", yytname[yyr1[yyn]]);
}
#endif
switch (yyn) {
case 4:
#line 36 "bis1.y"
{ printf ("The result is:\t%.10g\n", yyvsp[-1].val); ;
break;}
case 5:
#line 37 "bis1.y"
{ yyerrok; ;
break;}
case 6:
#line 40 "bis1.y"
{ yyval.val = yyvsp[0].val; ;
break;}
case 7:
#line 41 "bis1.y"
{ yyval.val = yyvsp[0].tptr->value.var; if(strcmp(yyvsp[0].tptr->name,"quit")==0){printf("\n********Bye-bye************\n");exit(0);} ;
break;}
case 8:
#line 42 "bis1.y"
{ yyval.val = yyvsp[0].val; yyvsp[-2].tptr->value.var = yyvsp[0].val; ;
break;}
case 9:
#line 43 "bis1.y"
{ yyval.val = (*(yyvsp[-3].tptr->value.fnctptr))(yyvsp[-1].val); ;
break;}
case 10:
#line 45 "bis1.y"
{ yyval.val = yyvsp[-2].val + yyvsp[0].val; ;
break;}
case 11:
#line 46 "bis1.y"
{ yyval.val = yyvsp[-2].val - yyvsp[0].val; ;
break;}
case 12:
#line 47 "bis1.y"
{ yyval.val = yyvsp[-2].val * yyvsp[0].val; ;
break;}
case 13:
#line 48 "bis1.y"
{ if(yyvsp[0].val==0){printf("The Zero flowover\n");yyval.val=0;} else yyval.val = yyvsp[-2].val / yyvsp[0].val; ;
break;}
case 14:
#line 49 "bis1.y"
{ yyval.val = -yyvsp[0].val; ;
break;}
case 15:
#line 50 "bis1.y"
{ yyval.val = pow (yyvsp[-2].val, yyvsp[0].val); ;
break;}
case 16:
#line 51 "bis1.y"
{ yyval.val = yyvsp[-1].val; ;
break;}
}
/* the action file gets copied in in place of this dollarsign */
#line 487 "bison.simple"
yyvsp -= yylen;
yyssp -= yylen;
#ifdef YYLSP_NEEDED
yylsp -= yylen;
#endif
#if YYDEBUG != 0
if (yydebug)
{
short *ssp1 = yyss - 1;
fprintf (stderr, "state stack now");
while (ssp1 != yyssp)
fprintf (stderr, " %d", *++ssp1);
fprintf (stderr, "\n");
}
#endif
*++yyvsp = yyval;
#ifdef YYLSP_NEEDED
yylsp++;
if (yylen == 0)
{
yylsp->first_line = yylloc.first_line;
yylsp->first_column = yylloc.first_column;
yylsp->last_line = (yylsp-1)->last_line;
yylsp->last_column = (yylsp-1)->last_column;
yylsp->text = 0;
}
else
{
yylsp->last_line = (yylsp+yylen-1)->last_line;
yylsp->last_column = (yylsp+yylen-1)->last_column;
}
#endif
/* Now "shift" the result of the reduction.
Determine what state that goes to,
based on the state we popped back to
and the rule number reduced by. */
yyn = yyr1[yyn];
yystate = yypgoto[yyn - YYNTBASE] + *yyssp;
if (yystate >= 0 && yystate <= YYLAST && yycheck[yystate] == *yyssp)
yystate = yytable[yystate];
else
yystate = yydefgoto[yyn - YYNTBASE];
goto yynewstate;
yyerrlab: /* here on detecting error */
if (! yyerrstatus)
/* If not already recovering from an error, report this error. */
{
++yynerrs;
#ifdef YYERROR_VERBOSE
yyn = yypact[yystate];
if (yyn > YYFLAG && yyn < YYLAST)
{
int size = 0;
char *msg;
int x, count;
count = 0;
/* Start X at -yyn if nec to avoid negative indexes in yycheck. */
for (x = (yyn < 0 ? -yyn : 0);
x < (sizeof(yytname) / sizeof(char *)); x++)
if (yycheck[x + yyn] == x)
size += strlen(yytname[x]) + 15, count++;
msg = (char *) malloc(size + 15);
if (msg != 0)
{
strcpy(msg, "parse error");
if (count < 5)
{
count = 0;
for (x = (yyn < 0 ? -yyn : 0);
x < (sizeof(yytname) / sizeof(char *)); x++)
if (yycheck[x + yyn] == x)
{
strcat(msg, count == 0 ? ", expecting `" : " or `");
strcat(msg, yytname[x]);
strcat(msg, "'");
count++;
}
}
yyerror(msg);
free(msg);
}
else
yyerror ("parse error; also virtual memory exceeded");
}
else
#endif /* YYERROR_VERBOSE */
yyerror("parse error");
}
goto yyerrlab1;
yyerrlab1: /* here on error raised explicitly by an action */
if (yyerrstatus == 3)
{
/* if just tried and failed to reuse lookahead token after an error, discard it. */
/* return failure if at end of input */
if (yychar == YYEOF)
YYABORT;
#if YYDEBUG != 0
if (yydebug)
fprintf(stderr, "Discarding token %d (%s).\n", yychar, yytname[yychar1]);
#endif
yychar = YYEMPTY;
}
/* Else will try to reuse lookahead token
after shifting the error token. */
yyerrstatus = 3; /* Each real token shifted decrements this */
goto yyerrhandle;
yyerrdefault: /* current state does not do anything special for the error token. */
#if 0
/* This is wrong; only states that explicitly want error tokens
should shift them. */
yyn = yydefact[yystate]; /* If its default is to accept any token, ok. Otherwise pop it.*/
if (yyn) goto yydefault;
#endif
yyerrpop: /* pop the current state because it cannot handle the error token */
if (yyssp == yyss) YYABORT;
yyvsp--;
yystate = *--yyssp;
#ifdef YYLSP_NEEDED
yylsp--;
#endif
#if YYDEBUG != 0
if (yydebug)
{
short *ssp1 = yyss - 1;
fprintf (stderr, "Error: state stack now");
while (ssp1 != yyssp)
fprintf (stderr, " %d", *++ssp1);
fprintf (stderr, "\n");
}
#endif
yyerrhandle:
yyn = yypact[yystate];
if (yyn == YYFLAG)
goto yyerrdefault;
yyn += YYTERROR;
if (yyn < 0 || yyn > YYLAST || yycheck[yyn] != YYTERROR)
goto yyerrdefault;
yyn = yytable[yyn];
if (yyn < 0)
{
if (yyn == YYFLAG)
goto yyerrpop;
yyn = -yyn;
goto yyreduce;
}
else if (yyn == 0)
goto yyerrpop;
if (yyn == YYFINAL)
YYACCEPT;
#if YYDEBUG != 0
if (yydebug)
fprintf(stderr, "Shifting error token, ");
#endif
*++yyvsp = yylval;
#ifdef YYLSP_NEEDED
*++yylsp = yylloc;
#endif
yystate = yyn;
goto yynewstate;
}
#line 53 "bis1.y"
yyerror (s) /* Called by yyparse on error */
char *s;
{
printf ("%s\n", s);
printf ("Now word is: %s\n", yylval);
}
struct init
{
char *fname;
double (*fnct)();
};
struct init arith_fncts[]
= {
"sin", sin,
"cos", cos,
"atan", atan,
"ln", log,
"exp", exp,
"sqrt", sqrt,
0, 0
};
/* The symbol table: a chain of `struct symrec'. */
symrec *sym_table = (symrec *)0;
init_table () /* puts arithmetic functions in table. */
{
int i;
symrec *ptr;
for (i = 0; arith_fncts[i].fname != 0; i++)
{
ptr = putsym (arith_fncts[i].fname, FNCT);
ptr->value.fnctptr = arith_fncts[i].fnct;
}
}
symrec *
putsym (sym_name,sym_type)
char *sym_name;
int sym_type;
{
symrec *ptr;
ptr = (symrec *) malloc (sizeof (symrec));
ptr->name = (char *) malloc (strlen (sym_name) + 1);
strcpy (ptr->name,sym_name);
ptr->type = sym_type;
ptr->value.var = 0; /* set value to 0 even if fctn. */
ptr->next = (struct symrec *)sym_table;
sym_table = ptr;
return ptr;
}
symrec *
getsym (sym_name)
char *sym_name;
{
symrec *ptr;
for (ptr = sym_table; ptr != (symrec *) 0;
ptr = (symrec *)ptr->next)
if (strcmp (ptr->name,sym_name) == 0)
return ptr;
return 0;
}
main ()
{
init_table ();
printf("\n******Begin you can type 'quit' to exit anytime you want***********\n");
yyparse ();
}
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