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+/* File name: platy.c
+ * Purpose:This is the main program for Assignment#4 - Platypus Parser
+ *  CST8152 - Compilers
+ *  Version: 1.17.01
+ *  Author: Svillen Ranev
+ *  Date: 18 March 2017
+ */ 
+
+/* 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>
+
+#include "buffer.h"
+#include "token.h"
+#include "stable.h" /*Do not remove this line. SiR */
+#include "stable.h" /*Do not remove this line. SiR */
+/* Input buffer parameters */
+#define INIT_CAPACITY 200 /* initial buffer capacity */
+#define INC_FACTOR 15       /* increment factor */
+/* String Literal Table parameters */
+#define STR_INIT_CAPACITY 100 /* initial string literal table capacity */
+#define STR_CAPACITY_INC  50   /* initial string literal table capacity inc */
+/* Symbol Table default size */
+#define ST_DEF_SIZE 100 
+
+/*check for ANSI C compliancy */
+#define ANSI_C 0
+#if defined(__STDC__)
+#undef ANSI_C
+#define ANSI_C 1
+#endif
+
+/* Global objects - variables */
+static Buffer *sc_buf; /* pointer to input (source) buffer */
+Buffer * str_LTBL; /* this buffer implements String Literal Table */
+                  /* it is used as a repository for string literals */
+int scerrnum;     /* run-time error number = 0 by default (ANSI) */
+STD sym_table;    /* Symbol Table Descriptor */
+/*external objects */
+extern int synerrno /* number of syntax errors reported by the parser */;
+extern int line; /* source code line number - defined in scanner.c */
+/* function declarations (prototypes) */
+extern void parser(Buffer * sc_buf);
+/* For testing purposes */
+ extern void scanner_init(Buffer * sc_buf);
+/* extern Token malpar_next_token(Buffer * sc_buf);*/
+
+void err_printf(char *fmt, ...);
+void display (Buffer *ptrBuffer); 
+long get_filesize(char *fname);
+void garbage_collect(void);
+
+
+/*  main function takes a PLATYPUS source file as
+ *  an argument at the command line.
+ *  usage: parser source_file_name [-stz size][-sts:A | -sts:D]
+ */    
+int main(int argc, char ** argv){
+
+	FILE *fi;       /* input file handle */	
+        int loadsize = 0; /*the size of the file loaded in the buffer */
+        int st_def_size = ST_DEF_SIZE; /* Sumbol Table default size */
+        char sort_st = 0;      /*Symbol Table sort switch */
+        int ansi_c = !ANSI_C; /* ANSI C flag */
+/* Check if the compiler option is set to compile ANSI C */
+/* __DATE__, __TIME__, __LINE__, __FILE__, __STDC__ are predefined preprocessor macros*/
+  if(ansi_c){
+    err_printf("Date: %s  Time: %s",__DATE__, __TIME__);
+    err_printf("ERROR: Compiler is not ANSI C compliant!\n");
+    exit(1);
+  }
+
+/*check for correct arrguments - source file name */
+      if (argc <= 1){
+/* __DATE__, __TIME__, __LINE__, __FILE__ are predefined preprocessor macros*/
+       err_printf("Date: %s  Time: %s",__DATE__, __TIME__);
+       err_printf("Runtime error at line %d in file %s", __LINE__, __FILE__);
+       err_printf("%s%s%s",argv[0],": ","Missing source file name.");
+       err_printf("%s%s%s","Usage: ", "parser", "  source_file_name [-stz size][-sts:A | -sts:D]");
+        exit(EXIT_FAILURE);
+	}	
+
+ /* check for optional switches - symbol table size and/or sort */
+ if (argc == 3){
+    if (strcmp(argv[2],"-sts:A") && strcmp(argv[2],"-sts:D") ){
+      err_printf("%s%s%s",argv[0],": ","Invalid switch.");
+      err_printf("%s%s\b\b\b\b%s","Usage: ", argv[0], " source file name [-stz size][-sts:A | -sts:D]");
+      exit(EXIT_FAILURE);
+    }
+    if(strcmp(argv[2],"-sts:A"))
+     sort_st = 'D';
+    else 
+     sort_st = 'A';
+ }
+/* symbol table size specified */ 
+ if (argc == 4){
+   if (strcmp(argv[2],"-stz")){
+     err_printf("%s%s%s",argv[0],": ","Invalid switch.");
+     err_printf("%s%s\b\b\b\b%s","Usage: ", argv[0], " source file name [-stz size][-sts:A | -sts:D]");
+     exit(EXIT_FAILURE);
+   }
+/* convert the symbol table size */
+    st_def_size = atoi(argv[3]);
+      if (st_def_size <= 0){
+	err_printf("%s%s%s",argv[0],": ","Invalid switch.");
+	err_printf("%s%s\b\b\b\b%s","Usage: ", argv[0], " source file name [-stz size][-sts:A | -sts:D]");
+	exit(EXIT_FAILURE);
+      }
+ }
+if (argc == 5){  
+    if (strcmp(argv[2],"-stz")){
+     err_printf("%s%s%s",argv[0],": ","Invalid switch.");
+     err_printf("%s%s\b\b\b\b%s","Usage: ", argv[0], " source file name [-stz size][-sts:A | -sts:D]");
+     exit(EXIT_FAILURE);
+   }
+/* convert the symbol table size */
+    st_def_size = atoi(argv[3]);
+      if (st_def_size <= 0){
+	err_printf("%s%s%s",argv[0],": ","Invalid switch.");
+	err_printf("%s%s\b\b\b\b%s","Usage: ", argv[0], " source file name [-stz size][-sts:A | -sts:D]");
+	exit(EXIT_FAILURE);
+   }
+    
+    if (strcmp(argv[4],"-sts:A")&& strcmp(argv[4],"-sts:D") ){
+      err_printf("%s%s%s",argv[0],": ","Invalid switch.");
+      err_printf("%s%s\b\b\b\b%s","Usage: ", argv[0], " source file name [-stz size][-sts:A | -sts:D]");
+      exit(EXIT_FAILURE);
+    }
+   if(strcmp(argv[4],"-sts:A"))
+     sort_st = 'D';
+    else 
+     sort_st = 'A';
+ }
+/* create a source code input buffer - multiplicative mode */	
+	sc_buf = b_create(INIT_CAPACITY,INC_FACTOR,'m');
+	if (sc_buf == NULL){
+	  err_printf("%s%s%s",argv[0],": ","Could not create source buffer");
+	  exit(EXIT_FAILURE);
+	}
+
+/* create symbol table */
+  sym_table = st_create(st_def_size);
+  if (!sym_table.st_size){
+    err_printf("%s%s%s",argv[0],": ","Could not create symbol table");
+    exit (EXIT_FAILURE);
+  }
+
+/*open source file */
+	if ((fi = fopen(argv[1],"r")) == NULL){
+		err_printf("%s%s%s%s",argv[0],": ", "Cannot open file: ",argv[1]);
+		exit (1);
+	}
+/* load source file into input buffer  */
+     printf("Reading file %s ....Please wait\n",argv[1]);
+     loadsize = b_load (fi,sc_buf);
+     if(loadsize == R_FAIL1)
+       err_printf("%s%s%s",argv[0],": ","Error in loading buffer.");
+
+/* close source file */	
+ 	fclose(fi);
+/*find the size of the file  */
+    if (loadsize == LOAD_FAIL){
+     printf("The input file %s %s\n", argv[1],"is not completely loaded.");
+     printf("Input file size: %ld\n", get_filesize(argv[1]));
+    }
+/* pack and display the source buffer */
+
+       if(b_pack(sc_buf)){
+         display(sc_buf);
+  }
+/* create string Literal Table */
+  str_LTBL = b_create(INIT_CAPACITY,INC_FACTOR,'a');
+	if (str_LTBL == NULL){
+		err_printf("%s%s%s",argv[0],": ","Could not create string buffer");
+		exit(EXIT_FAILURE);
+	}
+
+/*registrer exit function */	
+ atexit(garbage_collect);
+	
+/*Testbed for buffer, scanner,symbol table and parser*/
+
+/* Initialize scanner  */
+	scanner_init(sc_buf);
+/* Add SEOF (EOF) to input buffer */ 
+	b_addc(sc_buf, EOF);
+/* Start parsing */
+	printf("\nParsing the source file...\n\n");
+	
+        parser(sc_buf);
+        
+/* print Symbol Table */    
+/* 
+	 if(sym_table.st_size && sort_st){   
+           st_print(sym_table);
+           if(sort_st){
+            printf("\nSorting symbol table...\n");
+            st_sort(sym_table,sort_st);
+            st_print(sym_table);
+         }
+       }
+*/       
+	return (EXIT_SUCCESS); /* same effect as exit(0) */
+}/*end of main */
+
+/* Error printing function with variable number of arguments
+ */
+void err_printf( char *fmt, ... ){
+
+  va_list ap;
+  va_start(ap, fmt);
+
+  (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 
+ */
+long get_filesize(char  *fname){
+   FILE *input;
+   long flength;
+   input = fopen(fname, "r");
+   if(input == NULL){
+      err_printf("%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 
+ */
+void display (Buffer *ptrBuffer){
+  printf("\nPrinting input buffer parameters:\n\n");
+  printf("The capacity of the buffer is:  %d\n",b_capacity(ptrBuffer));
+  printf("The current size of the buffer is:  %d\n",b_size(ptrBuffer)); 
+  printf("\nPrinting input buffer contents:\n\n");
+  b_print(ptrBuffer);
+}
+
+/* the functions frees the allocated memory */
+void garbage_collect(void){
+  if(synerrno)
+    printf("\nSyntax errors: %d\n",synerrno);
+  printf("\nCollecting garbage...\n");
+  b_free(sc_buf);
+  b_free(str_LTBL);  
+  st_destroy(sym_table);
+}
+
+