initial commit

src/util.c

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+/****************************************************/
+/* File: util.c                                     */
+/* Utility function implementation                  */
+/* for the TINY compiler                            */
+/* Compiler Construction: Principles and Practice   */
+/* Kenneth C. Louden                                */
+/****************************************************/
+
+#include "globals.h"
+#include "util.h"
+
+/* Procedure printToken prints a token 
+ * and its lexeme to the listing file
+ */
+void printToken( TokenType token, const char* tokenString )
+{ switch (token)
+  { case IF:
+    case THEN:
+    case ELSE:
+    case END:
+    case REPEAT:
+    case UNTIL:
+    case READ:
+    case WRITE:
+      fprintf(listing,
+         "reserved word: %s\n",tokenString);
+      break;
+    case ASSIGN: fprintf(listing,":=\n"); break;
+    case LT: fprintf(listing,"<\n"); break;
+    case EQ: fprintf(listing,"=\n"); break;
+    case LPAREN: fprintf(listing,"(\n"); break;
+    case RPAREN: fprintf(listing,")\n"); break;
+    case SEMI: fprintf(listing,";\n"); break;
+    case PLUS: fprintf(listing,"+\n"); break;
+    case MINUS: fprintf(listing,"-\n"); break;
+    case TIMES: fprintf(listing,"*\n"); break;
+    case OVER: fprintf(listing,"/\n"); break;
+    case ENDFILE: fprintf(listing,"EOF\n"); break;
+    case NUM:
+      fprintf(listing,
+          "NUM, val= %s\n",tokenString);
+      break;
+    case ID:
+      fprintf(listing,
+          "ID, name= %s\n",tokenString);
+      break;
+    case ERROR:
+      fprintf(listing,
+          "ERROR: %s\n",tokenString);
+      break;
+    default: /* should never happen */
+      fprintf(listing,"Unknown token: %d\n",token);
+  }
+}
+
+/* Function newStmtNode creates a new statement
+ * node for syntax tree construction
+ */
+TreeNode * newStmtNode(StmtKind kind)
+{ TreeNode * t = (TreeNode *) malloc(sizeof(TreeNode));
+  int i;
+  if (t==NULL)
+    fprintf(listing,"Out of memory error at line %d\n",lineno);
+  else {
+    for (i=0;i<MAXCHILDREN;i++) t->child[i] = NULL;
+    t->sibling = NULL;
+    t->nodekind = StmtK;
+    t->kind.stmt = kind;
+    t->lineno = lineno;
+  }
+  return t;
+}
+
+/* Function newExpNode creates a new expression 
+ * node for syntax tree construction
+ */
+TreeNode * newExpNode(ExpKind kind)
+{ TreeNode * t = (TreeNode *) malloc(sizeof(TreeNode));
+  int i;
+  if (t==NULL)
+    fprintf(listing,"Out of memory error at line %d\n",lineno);
+  else {
+    for (i=0;i<MAXCHILDREN;i++) t->child[i] = NULL;
+    t->sibling = NULL;
+    t->nodekind = ExpK;
+    t->kind.exp = kind;
+    t->lineno = lineno;
+    t->type = Void;
+  }
+  return t;
+}
+
+/* Function copyString allocates and makes a new
+ * copy of an existing string
+ */
+char * copyString(char * s)
+{ int n;
+  char * t;
+  if (s==NULL) return NULL;
+  n = strlen(s)+1;
+  t = malloc(n);
+  if (t==NULL)
+    fprintf(listing,"Out of memory error at line %d\n",lineno);
+  else strcpy(t,s);
+  return t;
+}
+
+/* Variable indentno is used by printTree to
+ * store current number of spaces to indent
+ */
+static indentno = 0;
+
+/* macros to increase/decrease indentation */
+#define INDENT indentno+=2
+#define UNINDENT indentno-=2
+
+/* printSpaces indents by printing spaces */
+static void printSpaces(void)
+{ int i;
+  for (i=0;i<indentno;i++)
+    fprintf(listing," ");
+}
+
+/* procedure printTree prints a syntax tree to the 
+ * listing file using indentation to indicate subtrees
+ */
+void printTree( TreeNode * tree )
+{ int i;
+  INDENT;
+  while (tree != NULL) {
+    printSpaces();
+    if (tree->nodekind==StmtK)
+    { switch (tree->kind.stmt) {
+        case IfK:
+          fprintf(listing,"If\n");
+          break;
+        case RepeatK:
+          fprintf(listing,"Repeat\n");
+          break;
+        case AssignK:
+          fprintf(listing,"Assign to: %s\n",tree->attr.name);
+          break;
+        case ReadK:
+          fprintf(listing,"Read: %s\n",tree->attr.name);
+          break;
+        case WriteK:
+          fprintf(listing,"Write\n");
+          break;
+        default:
+          fprintf(listing,"Unknown ExpNode kind\n");
+          break;
+      }
+    }
+    else if (tree->nodekind==ExpK)
+    { switch (tree->kind.exp) {
+        case OpK:
+          fprintf(listing,"Op: ");
+          printToken(tree->attr.op,"\0");
+          break;
+        case ConstK:
+          fprintf(listing,"Const: %d\n",tree->attr.val);
+          break;
+        case IdK:
+          fprintf(listing,"Id: %s\n",tree->attr.name);
+          break;
+        default:
+          fprintf(listing,"Unknown ExpNode kind\n");
+          break;
+      }
+    }
+    else fprintf(listing,"Unknown node kind\n");
+    for (i=0;i<MAXCHILDREN;i++)
+         printTree(tree->child[i]);
+    tree = tree->sibling;
+  }
+  UNINDENT;
+}