run.cpp

   1 #include "stdafx.h"
   2 #include "defs.h"
   3
   4 jmp_buf stop_return, draw_stop_return;
   5
   6 void
   7 stop(char *s)
   8 {
   9         if (draw_flag == 2)
  10                 longjmp(draw_stop_return, 1);
  11         else {
  12                 printstr("Stop: ");
  13                 printstr(s);
  14                 printstr(" ");
  15                 longjmp(stop_return, 1);
  16         }
  17 }
  18
  19 void
  20 run(char *s)
  21 {
  22         int i, n;
  23
  24         /*if (strncmp(s, "selftest", 8) == 0) {
  25                 selftest();
  26                 return;
  27         }*/
  28
  29         if (setjmp(stop_return))
  30                 return;
  31
  32         init();
  33
  34         while (1) {
  35
  36                 n = scan(s);
  37
  38                 p1 = pop();
  39                 check_stack();
  40
  41                 if (n == 0)
  42                         break;
  43
  44                 // if debug mode then print the source text
  45
  46                 if (equaln(get_binding(symbol(TRACE)), 1)) {
  47                         for (i = 0; i < n; i++)
  48                                 if (s[i] != ' ')
  49                                         printchar(s[i]);
  50                         if (s[n - 1] != ' ') // n is not zero, see above
  51                                 printchar(' ');
  52                 }
  53
  54                 s += n;
  55
  56                 push(p1);
  57                 top_level_eval();
  58
  59                 p2 = pop();
  60                 check_stack();
  61
  62                 if (p2 == symbol(NIL))
  63                         continue;
  64
  65                 // print string w/o quotes
  66
  67                 if (isstr(p2)) {
  68                         printstr(p2->u.str);
  69                         printstr(" ");
  70                         continue;
  71                 }
  72
  73                 if (equaln(get_binding(symbol(TTY)), 1) || test_flag) // tty mode?
  74                         printline(p2);
  75                 else {
  76 //#ifdef LINUX
  77                         display(p2);
  78 /*#else
  79                         push(p2);
  80                         cmdisplay();
  81 #endif*/
  82                 }
  83         }
  84 }
  85
  86 void
  87 check_stack(void)
  88 {
  89         if (tos != 0)
  90                 stop("stack error");
  91         if (frame != stack + TOS)
  92                 stop("frame error");
  93 }
  94
  95 // cannot reference symbols yet
  96
  97 void
  98 echo_input(char *s)
  99 {
 100         printstr(s);
 101         printstr(" ");
 102 }
 103
 104 // returns nil on stack if no result to print
 105
 106 void
 107 top_level_eval(void)
 108 {
 109         save();
 110
 111         trigmode = 0;
 112
 113         p1 = symbol(AUTOEXPAND);
 114
 115         if (iszero(get_binding(p1)))
 116                 expanding = 0;
 117         else
 118                 expanding = 1;
 119
 120         p1 = pop();
 121         push(p1);
 122         eval();
 123         p2 = pop();
 124
 125         // "draw", "for" and "setq" return "nil", there is no result to print
 126
 127         if (p2 == symbol(NIL)) {
 128                 push(p2);
 129                 restore();
 130                 return;
 131         }
 132
 133         // update "last"
 134
 135         set_binding(symbol(LAST), p2);
 136
 137         if (!iszero(get_binding(symbol(BAKE)))) {
 138                 push(p2);
 139                 bake();
 140                 p2 = pop();
 141         }
 142
 143         // If we evaluated the symbol "i" or "j" and the result was sqrt(-1)
 144
 145         // then don't do anything.
 146
 147         // Otherwise if "j" is an imaginary unit then subst.
 148
 149         // Otherwise if "i" is an imaginary unit then subst.
 150
 151         if ((p1 == symbol(SYMBOL_I) || p1 == symbol(SYMBOL_J))
 152         && isimaginaryunit(p2))
 153                 ;
 154         else if (isimaginaryunit(get_binding(symbol(SYMBOL_J)))) {
 155                 push(p2);
 156                 push(imaginaryunit);
 157                 push_symbol(SYMBOL_J);
 158                 subst();
 159                 p2 = pop();
 160         } else if (isimaginaryunit(get_binding(symbol(SYMBOL_I)))) {
 161                 push(p2);
 162                 push(imaginaryunit);
 163                 push_symbol(SYMBOL_I);
 164                 subst();
 165                 p2 = pop();
 166         }
 167
 168 #ifndef LINUX
 169
 170         // if we evaluated the symbol "a" and got "b" then print "a=b"
 171
 172         // do not print "a=a"
 173
 174         if (issymbol(p1) && !iskeyword(p1) && p1 != p2 && test_flag == 0) {
 175                 push_symbol(SETQ);
 176                 push(p1);
 177                 push(p2);
 178                 list(3);
 179                 p2 = pop();
 180         }
 181 #endif
 182         push(p2);
 183
 184         restore();
 185 }
 186
 187 void
 188 check_esc_flag(void)
 189 {
 190         if (esc_flag)
 191                 stop("esc key");
 192 }