UNIX

yyerror(s) /* report compile-time error */

 char *s;

{

 warning(s, (char *)0);

}

execerror(s, t) /* recover from run-time error */

 char *s, *t;

{

 warning(s, t);

 fseek(fin, 0L, 2); /* flush rest of file */

 longjmp(begin, 0);

}

fpecatch() /* catch floating point exceptions */

{

 execerror("floating point exception", (char*)0);

}

main(argc, argv) /* hoc6 */

 char *argv[];

{

 int i, fpecatch();

 progname = argv[0];

 if (argc == 1) { /* fake an argument list */

  static char *stdinonly[] = { "-" };

  gargv = stdinonly;

  gargc = 1;

 } else {

  gargv = argv+1;

  gargc = argc-1;

 }

 init();

 while (moreinput())

  run();

 return 0;

}

moreinput() {

 if (gargc-- <= 0)

  return 0;

 if (fin && fin != stdin)

  fclose(fin);

 infile = *gargv++;

 lineno = 1;

 if (strcmp(infile, "-") == 0) {

  fin = stdin;

  infile = 0;

 } else if ((fin=fopen(infile, "r")) == NULL) {

  fprintf (stderr, "%s: can't open %s\n", progname, infile);

  return moreinput();

 }

 return 1;

}

run() /* execute until EOF */

{

 setjmp(begin);

 signal(SIGFPE, fpecatch);

 for (initcode(); yyparse(); initcode())

  execute(progbase);

}

warning(s, t) /* print warning message */

 char *s, *t;

{

 fprintf(stderr, "%s: %s", progname, s);

 if (t)

  fprintf(stderr, " %s", t);

 if (infile)

  fprintf(stderr, " in %s", infile);

 fprintf(stderr, " near line %d\n", lineno);

 while (c != '\n' && c != EOF)

  с = getc(fin); /* flush rest of input line */

 if (c == '\n')

  lineno++;

}

3.7.15 init.c

#include "hoc.h"

#include "y.tab.h"

#include

extern double Log(), Log10(), Sqrt(), Exp(), integer();

static struct { /* Keywords */

 char *name;

 int kval;

} keywords[] = {

 "proc",   PROC,

 "func",   FUNC,

 "return", RETURN,

 "if",     IF,

 "else",   ELSE,

 "while",  WHILE,

 "print",  PRINT,

 "read",   READ,

 0,        0,

};

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;

 double (*func)();

} builtins[] = {

 "sin",   sin,

 "cos",   cos,

 "atan",  atan,

 "log",   Log, /* checks range */

 "log10", Log10, /* checks range */

 "exp",   Exp, /* checks range */

 "sqrt",  Sqrt, /* checks range */

 "int",   integer,

 "abs",   fabs,

 0, 0

};

init() /* install constants and built-ins in table */

{

 int i;

 Symbol *s;

 for (i = 0; keywords[i].name; i++)

  install(keywords[i].name, keywords[i].kval, 0.0);

 for (i = 0; consts[i].name; i++)

  install(consts[i].name, VAR, consts[i].eval);

 for (i = 0; builtins[i].name; i++) {

  s = install(builtins[i].name, BLTIN, 0.0);