int parseTester() {
int depth = 0;
char *expression = malloc(256 * sizeof(char)); /* i dont think we need to malloc this */
Value **tokens = NULL;
Value **leftoverTokens = NULL;
Value **parseTree = NULL;
printf("> ");
while (fgets(expression, 255, stdin)) {
tokens = append(leftoverTokens, tokenize(expression));
if (tokens) { printf("\nTOKENS:\n"); printTokens(*tokens); }
parseTree = parse(tokens, &depth);
if (depth > 0) {
leftoverTokens = tokens;
depth = 0;
}
else {
if (parseTree) {
printf("\nPARSE TREE:\n");
printParseTree(*parseTree);
printf("\n");
}
else { depth = 0; }
leftoverTokens = NULL;
printf("> ");
}
}
free(expression);
return 0;
}
int main(int argc, char** argv)
{
// details of implementation (as per the assignment requirements)
printf("(a) Lexer implemented using TWIN BUFFER\n");
printf("(b) FIRST set automated, hardcoded FOLLOW set taken as input from a text file\n");
printf("(c) Both lexical and syntax analysis modules implemented\n");
printf("(d) PARSE TABLE generated\n");
printf("(e) STACK for syntax checking successfully implemented\n");
printf("(f) Catches only one syntax error at a time.\n");
printf("(g) PARSE TREE successfully generated\n");
printf("(h) All 3 option in driver working\n");
printf(" Press option for the defined task\n");
printf("1 : for printing the token list (on the console) generated by the lexer. Each token appears in a new line alongwith the corresponding lexeme\n");
printf("2 : for parsing to verify the syntactic correctness of the input source code \n");
printf("3 : for creating the parse tree and printing it appropriately\n");
int option;
scanf("%d", &option);
if(option == 1)
{
FILE *dfafp = fopen("dfa.txt", "r");
TreeNode *dfa;
dfa = (TreeNode *)createDFA(dfafp, dfa);
FILE *fp = fopen(*++argv, "r");
buffersize k = 1000;
buffer b = createBuffer(k);
tokenInfo info = getNextToken(fp, dfa, b, k);
// print all tokens in the input program
while(info.value != NULL)
{
printf("%s\t%s\n", info.tokenName, info.value);
info = getNextToken(fp, dfa, b, k);
}
}
else if(option == 2)
{
table t;
parseTree parsetree = parseInputSourceCode(*++argv, t);
}
else if(option == 3)
{
table t;
parseTree parsetree = parseInputSourceCode(*++argv, t);
printParseTree(parsetree, *++argv);
}
return 0;
}
int printOnlyParsetree(Parser* p, Lexer lex, char* outPutTreeFile, int isParsed)
{
if (isParsed==PARSER_NOT_INVOKED)
{
isParsed = parseOnlySourceCode(p, lex);
}
if (isParsed == PARSED_SUCCESSFULLY)
{
printParseTree(p->parseTree, outPutTreeFile);
return isParsed;
}
else
{
return isParsed;
}
}
ParseTree initializeParser(char *filename)
{
//input file is the token file name
FILE *fp;
char ptreename[50];
ParseTree parse_tree = (ParseTree)malloc(sizeof(struct ptree));
//check if parsing table is already available.
//If yes then read it, else compute and save it.
fp = fopen("parsingtable","r");
if(fp==NULL)
{
//construct first-follow sets
constructSTable();
//construct predictive parsing table
constructParsingTable();
//save parsing table to disk file
saveParsingTables();
}
else
{
//read parsing table from disk
loadParsingTables(fp);
fclose(fp);
}
//Open token file and read the first symbol.
token_file = fopen(filename,"r");
advance(token_file);
//invoke parser. Assume starting symbol of the grammar is "Programs"
parse_tree = parse(findSymbol("Programs"),parse_tree);
//now print the parse tree into the file
strcpy(ptreename,filename);
strcat(ptreename,".ptree");
ftree = fopen(ptreename,"w");
printParseTree(parse_tree,0);
/*Expected call for the symbol table*/
//dfs_parsetree(parse_tree);
/*Call for Symbol Table*/
fclose(ftree);
fclose(token_file);
return parse_tree;
}
void printParseTree(ParseTree parse_tree, int level)
{
/*Prints the Parse Tree into the file 'parse_tree'*/
/*level: The current depth of the parse tree*/
int i,j;
if(parse_tree->num_branches>0)
{
if(level==0)
fprintf(ftree,"%s\n",parse_tree->node->name);
for(i=0;i<parse_tree->num_branches;i++)
{
for(j=0;j<level;j++)
fprintf(ftree," ");
fprintf(ftree,"|_%s",parse_tree->branches[i]->node->name);
if((strcmp(parse_tree->branches[i]->node->name, "TK_ID")==0)||\
(strcmp(parse_tree->branches[i]->node->name, "TK_NUM")==0))
fprintf(ftree,":%s",parse_tree->branches[i]->node->id_or_num);
fprintf(ftree,"\n");
printParseTree(parse_tree->branches[i],level+1);
}
}
}
void printParseTree(Node* head) {
while (head) {
switch (head->value->type) {
case booleanType:
if (head->value->val.boolValue) {
printf("#t ");
}
else {
printf("#f ");
}
break;
case integerType:
printf("%d", head->value->val.integerValue);
break;
case floatType:
printf("%f", head->value->val.floatValue);
break;
case openType:
printf("%s", head->value->val.openValue);
break;
case closeType:
printf("%s", head->value->val.closeValue);
break;
case symbolType:
printf("%s", head->value->val.symbolValue);
break;
case quoteType:
printf("%s", head->value->val.quoteValue);
break;
case stringType:
printf("%s", head->value->val.stringValue);
break;
case listType:
printf("(");
printParseTree(head->value->val.listValue->head);
printf(")");
break;
default:
printf("invalid type for value structure\n");
break;
}
if (head->next) {
printf(" ");
}
//printf("next in printParseTree\n");
head = head->next;
}
}
void printParseTree(ConsCell* parseTree)
{
while(parseTree != NULL && parseTree->car != NULL)
{
Value* currentValue = pop(&parseTree);
switch(currentValue->type)
{
case 0:
printf("%s ", currentValue->uni.boolValue == 1 ? "#t" : "#f");
//free(currentValue);
break;
case 1:
printf("%d ",currentValue->uni.intValue);
//free(currentValue);
break;
case 2:
printf("%c ",currentValue->uni.quote);
//free(currentValue);
break;
case 3:
printf("%f ",currentValue->uni.floatValue);
//free(currentValue);
break;
case 4:
printf("%s ",currentValue->uni.symbol);
//free(currentValue);
break;
case 5:
printf("%s ",currentValue->uni.stringValue);
//free(currentValue);
break;
case 6:
printf("%c",currentValue->uni.open);
//free(currentValue);
break;
case 7:
printf("%c ",currentValue->uni.close);
//free(currentValue);
pop(&parseTree);
printParseTree(parseTree);
return;
case 8:
//printf("(");
//printf("printing case 8");
printParseTree(currentValue->uni.cons);
//freeParseTree(currentValue);
//printf(")");
break;
case 11:
printf("Symbol: %s ", currentValue->uni.binding->symbol);
printf("Bound type: %d ", currentValue->uni.binding->val->type);
default:
//printf("SYNTAX ERROR\n");
//printf("weird default");
break;
}
}
}
