Шрифт:
#include <ctype.h>
char *progname;
int lineno = 1;
#include <signal.h>
#include <setjmp.h>
jmp_buf begin;
main(argc, argv) /* hoc4 */
char *argv[];
{
int fpecatch;
progname = argv[0];
init;
setjmp(begin);
signal(SIGFPE, fpecatch);
for (initcode; yyparse; initcode)
execute(prog);
return 0;
}
static int c; /* global for use by warning */
yylex /* hoc4 */
{
while ((c=getchar) == ' ' || с == '\t')
;
if (c == EOF)
return 0;
if (c == '.' || isdigit(c)) { /* number */
double d;
ungetc(c, stdin);
scanf ("%lf", &d);
yylval.sym = install("", NUMBER, d);
return NUMBER;
}
if (isalpha(c)) {
Symbol *s;
char sbuf[100], *p = sbuf;
do {
*p++ = c;
} while ((c=getchar) != EOF && isalnum(c));
ungetc(c, stdin);
*p = '\0';
if ((s=lookup(sbuf)) == 0)
s = install(sbuf, UNDEF, 0.0);
yylval.sym = s;
return s->type == UNDEF ? VAR : s->type;
}
if (c == '\n')
lineno++;
return c;
}
yyerror(s)
char *s;
{
warning(s, (char *)0);
}
execerror(s, t) /* recover from run-time error */
char *s, *t;
{
warning(s, t);
longjmp(begin, 0);
}
fpecatch /* catch floating point exceptions */
{
execerror("floating point exception", (char*)0);
}
warning(s, t)
char *s, *t;
{
fprintf(stderr, "%s: %s", progname, s);
if (t && *t)
fprintf(stderr, " %s", t);
fprintf(stderr, " near line %d\n", lineno);
while (c != '\n' && с != EOF)
с = getchar; /* flush rest of input line */
}
3.5.4
init.c
#include "hoc.h"
#include "y.tab.h"
#include <math.h>
extern double Log, Log10, Exp, Sqrt, integer;
static struct { /* Constants */
char *name;
double eval;
} consts[] = {
"PI", 3.14159265358979323846,
"E", 2.71828182845904523536,
"GAMMA", 0.57721566490153286060, /* Euler */
"DEG", 57.29577951308232087680, /* deg/radian */
"PHI", 1.61803398874989484820, /* golden ratio */
0, 0
};
static struct { /* Built-ins */
char *name;