Add the tiger source code bundle from the book site

Signed-off-by: jmug <u.g.a.mariano@gmail.com>

tiger/chap12/runtime.c

@@ -0,0 +1,109 @@
+#undef __STDC__
+#include <stdio.h>
+
+
+int *initArray(int size, int init)
+{int i;
+ int *a = (int *)malloc(size*sizeof(int));
+ for(i=0;i<size;i++) a[i]=init;
+ return a;
+}
+
+int *allocRecord(int size)
+{int i;
+ int *p, *a;
+ p = a = (int *)malloc(size);
+ for(i=0;i<size;i+=sizeof(int)) *p++ = 0;
+ return a;
+}
+
+struct string {int length; unsigned char chars[1];};
+
+int stringEqual(struct string *s, struct string *t)
+{int i;
+ if (s==t) return 1;
+ if (s->length!=t->length) return 0;
+ for(i=0;i<s->length;i++) if (s->chars[i]!=t->chars[i]) return 0;
+ return 1;
+}
+
+void print(struct string *s)
+{int i; unsigned char *p=s->chars;
+ for(i=0;i<s->length;i++,p++) putchar(*p);
+}
+
+void flush()
+{
+ fflush(stdout);
+}
+
+struct string consts[256];
+struct string empty={0,""};
+
+int main()
+{int i;
+ for(i=0;i<256;i++)
+   {consts[i].length=1;
+    consts[i].chars[0]=i;
+   }
+ return tigermain(0 /* static link!? */);
+}
+
+int ord(struct string *s)
+{
+ if (s->length==0) return -1;
+ else return s->chars[0];
+}
+
+struct string *chr(int i)
+{
+ if (i<0 || i>=256) 
+   {printf("chr(%d) out of range\n",i); exit(1);}
+ return consts+i;
+}
+
+int size(struct string *s)
+{ 
+ return s->length;
+}
+
+struct string *substring(struct string *s, int first, int n)
+{
+ if (first<0 || first+n>s->length)
+   {printf("substring([%d],%d,%d) out of range\n",s->length,first,n);
+    exit(1);}
+ if (n==1) return consts+s->chars[first];
+ {struct string *t = (struct string *)malloc(sizeof(int)+n);
+  int i;
+  t->length=n;
+  for(i=0;i<n;i++) t->chars[i]=s->chars[first+i];
+  return t;
+ }
+}
+
+struct string *concat(struct string *a, struct string *b)
+{
+ if (a->length==0) return b;
+ else if (b->length==0) return a;
+ else {int i, n=a->length+b->length;
+       struct string *t = (struct string *)malloc(sizeof(int)+n);
+       t->length=n;
+       for (i=0;i<a->length;i++)
+	 t->chars[i]=a->chars[i];
+       for(i=0;i<b->length;i++)
+	 t->chars[i+a->length]=b->chars[i];
+       return t;
+     }
+}
+
+int not(int i)
+{ return !i;
+}
+
+#undef getchar
+
+struct string *getchar()
+{int i=getc(stdin);
+ if (i==EOF) return &empty;
+ else return consts+i;
+}