MainParser.c

/*
************************************************************
* COMPILERS COURSE - Algonquin College
* Code version: Fall, 2023
* Author: TO_DO
* Professors: Paulo Sousa
************************************************************
=---------------------------------------=
|  COMPILERS - ALGONQUIN COLLEGE (F23)  |
=---------------------------------------=
|              ....                     |
|          ........::.::::::.           |
|        .:........::.:^^^~~~:          |
|        :^^::::::^^^::^!7??7~^.        |
|       .:^~~^!77777~~7?YY?7??7^.       |
|       :.^~!??!^::::^^~!?5PY??!~.      |
|       ~!!7J~.:::^^^^~!!~~?G5J?~       |
|       :^~?!~7?Y57^^?PP5YJ!J5Y?:       |
|       .~!!.:^!7!:.:7JYYJ7~7Y7^        |
|       .~77..    . .~^:^^^~7?:         |
|       .^!^~:::.:^!7?~^~!77J:          |
|        ^^!Y~^^^^~?YJ77??7JJ^          |
|       .^7J?~^~~^~7??7??7JY?~:         |
|        ::^^~^7?!^~~!7???J?J7~:.       |
|         ^~~!.^7YPPPP5Y?7J7777~.       |
|        ..:~..:^!JPP5YJ?!777!^.        |
| .~?JJJJJJJJJJYYYYYPPPPPPPPPPPP5PPYY~  |
|  :!Y5GGG.___ YYYYYY__._.PPGGGGGG5!.   |
|   :!Y5G / __| ___ / _(_)__ _ PGP5.    |
|    :~75 \__ \/ _ \  _| / _` | 5?.     |
|     7~7 |___/\___/_| |_\__,_| Y5?.    |
|    .^~!~.....................P5YY7.   |
|   .:::::::::::::?JJJJYYYYYYYYYJJJJ7.  |
|                                       |
=---------------------------------------=
*/

/*
************************************************************
* File name: MainParser.c
* Compiler: MS Visual Studio 2022
* Course: CST 8152 – Compilers, Lab Section: [011, 012, 013]
* Assignment: A32.
* Date: May 01 2023
* Professor: Paulo Sousa
* Purpose: This file is the main code for Parser (A32)
* Function list: (...).
************************************************************
*/

/*
************************************************************
 * IMPORTANT NOTE:
 * The #define _CRT_SECURE_NO_WARNINGS should be used in MS Visual Studio projects
 * to suppress the warnings about using "unsafe" functions like fopen()
 * and standard sting library functions defined in string.h.
 * The define does not have any effect in other compilers  projects.
 *********************************************************
 */


#define _CRT_SECURE_NO_WARNINGS

#include <stdio.h>
#include <stdlib.h> /* Constants for calls to exit()*/

#include <string.h>
#include <stdarg.h>

#ifndef COMPILERS_H_
#include "Compilers.h"
#endif

#ifndef READER_H_
#include "Reader.h"
#endif

#ifndef SCANNER_H_
#include "Scanner.h"
#endif

#ifndef PARSER_H_
#include "Parser.h"
#endif

 /* Check for ANSI C compliancy */
#define ANSI_C 0
#if defined(__STDC__)
#undef ANSI_C
#define ANSI_C 1
#endif

/*
 * -------------------------------------------------------------
 *  Global vars and External vars
 * -------------------------------------------------------------
 */

 /* Global objects - variables */
static BufferPointer sourceBuffer; /* pointer to input (source) buffer */
BufferPointer stringLiteralTable; /* This buffer is used as a repository for string literals */
mobile_intg errorNumber;     /* Run-time error number = 0 by default (ANSI) */

/* External objects */
extern mobile_intg syntaxErrorNumber /* number of syntax errors reported by the parser */;
extern mobile_intg line; /* source code line number - defined in scanner.c */

extern ParserData psData;

/*
 * -------------------------------------------------------------
 *  Function declarations
 * -------------------------------------------------------------
 */

 /* Function declarations (prototypes) */
extern mobile_void startParser(sofia_void);
extern mobile_intg startScanner(BufferPointer sc_buf);

static mobile_void printParserError(mobile_string fmt, ...);
static mobile_void displayParser(BufferPointer ptrBuffer);
static mobile_long getParserFileSize(mobile_string fname);
static mobile_void callGarbageCollector(mobile_void);

/*
************************************************************
 *  Parser Main function
 *  Parameters:
 *  - argc / argv = Parameters from command prompt
 *  Return value:
 *	- Success operation.
***********************************************************
*/

mobile_intg mainParser(mobile_intg argc, mobile_string* argv) {

	numParserErrors = 0;			/* Initializes the errors */

	FILE* fi;       /* input file handle */
	mobile_intg loadsize = 0; /*the size of the file loaded in the buffer */

	/*check for correct arrguments - source file name */
	if (argc <= 1) {
		/* __DATE__, __TIME__, __LINE__, __FILE__ are predefined preprocessor macros*/
		printParserError("Date: %s  Time: %s", __DATE__, __TIME__);
		printParserError("Runtime error at line %d in file %s", __LINE__, __FILE__);
		printParserError("%s%s%s", argv[0], ": ", "Missing source file name.");
		printParserError("%s%s%s", "Usage: ", "parser", "  source_file_name");
		exit(EXIT_FAILURE);
	}

	/* create a source code input buffer - multiplicative mode */
	sourceBuffer = readerCreate(READER_DEFAULT_SIZE, READER_DEFAULT_INCREMENT, MODE_MULTI);
	if (sourceBuffer == NULL) {
		printParserError("%s%s%s", argv[0], ": ", "Could not create source buffer");
		exit(EXIT_FAILURE);
	}

	/*open source file */
	if ((fi = fopen(argv[2], "r")) == NULL) {
		printParserError("%s%s%s%s", argv[0], ": ", "Cannot open file: ", argv[2]);
		exit(EXIT_FAILURE);
	}

	/* load source file into input buffer  */
	printf("Reading file %s ....Please wait\n", argv[2]);
	loadsize = readerLoad(sourceBuffer, fi);
	if (loadsize == READER_ERROR)
		printParserError("%s%s%s", argv[0], ": ", "Error in loading buffer.");

	/* close source file */
	fclose(fi);
	/*find the size of the file  */
	if (loadsize == READER_ERROR) {
		printf("The input file %s %s\n", argv[2], "is not completely loaded.");
		printf("Input file size: %ld\n", getParserFileSize(argv[2]));
	}
	/* Add SEOF (EOF) to input buffer and display the source buffer */
	if ((loadsize != READER_ERROR) && (loadsize != 0)) {
		if (readerAddChar(sourceBuffer, READER_TERMINATOR)) {
			displayParser(sourceBuffer);
		}
	}
	/* create string Literal Table */
	stringLiteralTable = readerCreate(READER_DEFAULT_SIZE, READER_DEFAULT_INCREMENT, MODE_ADDIT);
	if (stringLiteralTable == NULL) {
		printParserError("%s%s%s", argv[0], ": ", "Could not create string literal buffer");
		exit(EXIT_FAILURE);
	}

	/* Registrer exit function */
	atexit(callGarbageCollector);

	/* Initialize scanner  */
	startScanner(sourceBuffer);

	/* Start parsing */
	printf("\nParsing the source file...\n\n");
	startParser();

	printf("\nNumber of Parser errors: %d\n", numParserErrors);

	/* Prints the statistics */
	printBNFData(psData);

	return (EXIT_SUCCESS); /* same effect as exit(0) */

}


void startParser() {
	lookahead = tokenizer();  // Get the first token
	program();  // Start parsing with the program rule
	matchToken(SEOF_T, NO_ATTR);  // Ensure the end of the file is reached
}

//void matchToken(int tokenCode, int tokenAttribute) {
	//if (lookahead.code == tokenCode && lookahead.attribute == tokenAttribute) {
		//lookahead = tokenizer();  // Move to the next token
	//}
//	else {
	//	printError();
	//}
//
void syncErrorHandler(int syncTokenCode) {
	// Handle errors by skipping tokens until a specific token is found
	while (lookahead.code != syncTokenCode) {
		lookahead = tokenizer();
	}
	lookahead = tokenizer();  // Move past the sync token
}

void printError() {
	printf("Syntax error at line %d\n", line);
	//errorCount++;
}
/*
************************************************************
 * Error printing function with variable number of arguments
 * Params: Variable arguments, using formats from C language.
 *	 - Internal vars use list of arguments and types from stdarg.h
 *   - NOTE: The format is using signature from C Language
************************************************************
*/

mobile_void printParserError(mobile_string fmt, ...) {

	va_list ap;
	va_start(ap, fmt);

	(mobile_void)vfprintf(stderr, fmt, ap);
	va_end(ap);

	/* Move to new line */
	if (strchr(fmt, '\n') == NULL)
		fprintf(stderr, "\n");
}

/*
************************************************************
* The function return the size of an open file
* Param:
*	- Filename
* Return:
*	- Size of the file
************************************************************
*/

mobile_long getParserFileSize(mobile_string fname) {
	FILE* input;
	mobile_long flength;
	input = fopen(fname, "r");
	if (input == NULL) {
		printParserError("%s%s", "Cannot open file: ", fname);
		return 0;
	}
	fseek(input, 0L, SEEK_END);
	flength = ftell(input);
	fclose(input);
	return flength;
}

/*
************************************************************
* The function display buffer contents
* Param:
*	- Parser to be displayed.
************************************************************
*/

mobile_void displayParser(BufferPointer ptrBuffer) {
	printf("\nPrinting input buffer parameters:\n\n");
	printf("The capacity of the buffer is:  %d\n", readerGetSize(ptrBuffer));
	printf("The current size of the buffer is:  %d\n", readerGetPosWrte(ptrBuffer));
	printf("\nPrinting input buffer contents:\n\n");
	readerRecover(ptrBuffer);
	readerPrint(ptrBuffer);
}

/*
************************************************************
* The function frees all dynamically allocated memory.
* This function is always called despite how the program terminates - normally or abnormally.
************************************************************
*/

mobile_void callGarbageCollector(sofia_void) {
	if (syntaxErrorNumber)
		printf("\nSyntax errors: %d\n", syntaxErrorNumber);
	printf("\nCollecting garbage...\n");
	readerFree(sourceBuffer);
	readerFree(stringLiteralTable);
}