Token Identification using Transition diagram

The following program uses transition diagram to identify the pre-defined tokens of C language. For valid token is will display the token type as well as state-table(traversal) and the states at which there is a failure. For invalid tokens it will simply print the states at which it has failed in different transition diagrams: Given below is a part of the transition diagram for pre-defined symbols: The states 34,36,38,40,42 and 44 are final states and will return "{",",",...",?" respectively

Here is the file of complete Transition diagram http://sdrv.ms/1at8wQ3



#include<string.h>
#include<stdlib.h>
#include<stdio.h>
#include<malloc.h>
#define TRUE 1
#define FALSE 0
int main(void)
{
char *str,ar[80];
char *start,*current,*next,*super;
char *ftest[45];
int *fail,iden_final[11],ope_final[7],sym_final[7];
int  count=0,n,len,i=0,key=TRUE,ide_len=0,state=0,choice;
int ide=TRUE,ide_t=TRUE,lit=TRUE,lit_t=TRUE,ope=TRUE,symb=TRUE,numb,negative=FALSE,j=0;
fail=(int *)malloc(44*sizeof(int));
for(i=0;i<45;i++)
{
fail[i]=FALSE;
ftest[i]=(char*)malloc(60*sizeof(char));
}
for(i=0;i<11;i++)
iden_final[i]=FALSE;
for(i=0;i<7;i++)
ope_final[i]=sym_final[i]=FALSE;
printf("\n Enter the maximum length of the statement:");
scanf(" %d", &n);
str=(char *)malloc( (n+1)*sizeof(char));
fflush(stdin);
printf("\n Enter the C statement:");
scanf("%[^\n]",str);
len=strlen(str);
if(len>n)
{
printf("\n Length of the statement is greater than the input length:");
exit(1);
}
super=str;
while(*super==' ')
super++;
while(*super !='\0' || *super =='\n')
{
start=super;
current=start;
next=current;
//Transistion diagram for Keywords int,if,for
switch(*current)
{
case 'i':
  //printf("\n>>>>>>>>%c",*current);
ar[0]=*current;
next +=1;
if(*next == ' ' || *next == '\0')
{
//printf("\n Failed at state 1:");
strcpy(ftest[1],"Failed at state 1:");
fail[1]=TRUE;
//ftest[strlen("Failed at state 1:")]='\0';
key=FALSE;
break;
}
current=next;
if(*current!='n' && *current !='f')
{
//printf("\n Failed at state 1:");
strcpy(ftest[1],"Failed at state 1:");
fail[1]=TRUE;
//ftest[strlen("Failed at state 1:")]='\0';
key=FALSE;
break;
}
ar[1]=*current;
 // printf("\n>>>>>n or f >>>%c",*current);
next +=1;
if(*next == ' ' || *next == '\0' || *current == 'f')
{
//   printf("\n In test loop:");
if(ar[1]!='f')
{
//printf("\n Failed at state 5:");
strcpy(ftest[5],"Failed at state 5:");
fail[5]=TRUE;
//ftest[strlen("Failed at state 5:")]='\0';
key=FALSE;
}
// printf("\n>>>>>>>>>>> [%c]",*next);
if(*next != ' ' && *next!='\0')
{
//printf("\n Failed at state 5:");
key=FALSE;
strcpy(ftest[5],"Failed at state 5:");
fail[5]=TRUE;
 // ftest[strlen("Failed at state 5:")]='\0';
break;
}
ar[2]='\0';
current=next;
if(key==TRUE)
iden_final[6]=TRUE;
printf("%s\t\t Keyword",ar);
break;
}
current=next;
if(*current!='t')
{
//printf("\n Failed at state 2:");
strcpy(ftest[2],"Failed at state 2:");
fail[2]=TRUE;
//ftest[strlen("Failed at state 2:")]='\0';
key=FALSE;
break;
}
ar[2]=*current;
//printf("\n>>>>>>>>%c",*current);
next +=1;
if(*next !=' ' && *next !='\0')
{
//printf("\n Failed at state 3:");
key=FALSE;
strcpy(ftest[3],"Failed at state 3:");
fail[3]=TRUE;
//ftest[strlen("Failed at state 3:")]='\0';
break;
}
current=next;
ar[3]='\0';
//printf("\nFFFFFFFF%c",*current);
iden_final[4]=TRUE;
printf("%s\t\t Keyword",ar);
break;
// CASE for
case 'f':
ar[0]=*current;
next +=1;
if(*next == ' ' || *next == '\0')
{
//printf("\n Failed at state 7:");
strcpy(ftest[7],"Failed at state 7:");
fail[7]=TRUE;
//ftest[strlen("Failed at state 7:")]='\0';
key=FALSE;
break;
}
current=next;
if(*current!='o')
{
//printf("\n Failed at state 7:");
strcpy(ftest[7],"Failed at state 7:");
fail[7]=TRUE;
//ftest[strlen("Failed at state 7:")]='\0';
key=FALSE;
break;
}
ar[1]=*current;
next +=1;
if(*next ==' ' && *next =='\0')
{
//printf("\n Failed at state 8:");
strcpy(ftest[8],"Failed at state 8:");
fail[8]=TRUE;
//ftest[strlen("Failed at state 8:")]='\0';
key=FALSE;
break;
}
current=next;
if(*current!='r')
{
//printf("\n Failed at state 8:");
strcpy(ftest[8],"Failed at state 8:");
fail[8]=TRUE;
//ftest[strlen("Failed at state 8:")]='\0';
key=FALSE;
break;
}
ar[2]=*current;
next +=1;
if(*next !=' ' && *next !='\0')
{
//printf("\n Failed at state 9:");
strcpy(ftest[9],"Failed at state 9:");
fail[9]=TRUE;
//ftest[strlen("Failed at state 9:")]='\0';
key=FALSE;
break;
}
current=next;
ar[3]='\0';
//printf("\nFFFFFFFF%c",*current);
iden_final[10]=TRUE;
printf("%s\t\t Keyword",ar);
break;
default:
//printf("\n Failure at state 0 in Keyword transistion:");
strcpy(ftest[0],"Failed at state 0:");
fail[0]=TRUE;
//ftest[strlen("Failed at state 0:")]='\0';
key=FALSE;
break;
}
// State traversal diagram
if(iden_final[6]==TRUE)
{
printf("\n i\t\t 0(s)---->1");
printf("\n f\t\t 1------->2");
printf("\n *D\t\t 5---->6(f)");
printf("\n");
}
if(iden_final[4]==TRUE)
{
printf("\n i\t\t 0(s)---->1");
printf("\n n\t\t 1------->2");
printf("\n t\t\t 2------->3");
printf("\n *D\t\t 3---->4(f)");
printf("\n");
}
 if(iden_final[10]==TRUE)
{
printf("\n f\t\t 0(s)---->7");
printf("\n 0\t\t 7------->8");
printf("\n r\t\t 8------->9");
printf("\n *D\t\t 9--->10(f)");
printf("\n");
}

// Transistion diagram for identifier
ide_len=0;
i=0;
if(key==FALSE)
{
state=0;
current=start;
while(*current!= ' ' && *current !='\0')
{
ar[i++]=*current;
current++;
}
ar[i]='\0';
current=start;
if( !(65 <= *current && *current <= 93 ) && !(97 <= *current && *current <= 122 )  )
{
//printf("\n Failed at state 11 in identifier transistion:");
strcpy(ftest[11],"Failed at state 11:");
fail[11]=TRUE;
//ftest[strlen("Failed at state 11:")]='\0';
ide_t=FALSE;
ide=FALSE;
}
current +=1;
next=current;
ide_len++;
while(*current!= ' ' && *current !='\0' && ide_t==TRUE)
{
if( (65 <= *current && *current <= 93 ) ||  ( 97 <= *current && *current <= 122)  || ( 48 <= *current && *current <= 57) || *current==95 )
{
ide_len++;
state++;
}
else
{
//printf("\n Failed at state 12:");
strcpy(ftest[1],"Failed at state 12:");
fail[12]=TRUE;
//ftest[strlen("Failed at state 12:")]='\0';
ide_t=FALSE;
ide=FALSE;
break;
}
current++;
}
if(ide_len>8 || ide_t==FALSE )
{ide=FALSE;}//printf("\n %s is Invalid identifier:",ar);
else
{
ide=TRUE;
printf("\n %s\t\t Identifier:",ar);
printf("\n %c\t\t11(s)------->12",ar[0]);
for(i=1;i<=state;i++)
printf("\n %c\t\t12------->12",ar[i]);
printf("\n *D\t\t12------->13");
printf("\n");
}

} // end of trans for iden
// Start of transisition for constant
i=0;
j=0;
state=0;
if(key==FALSE && ide==FALSE)
{
current=start;
while(*current!= ' ' && *current !='\0')
{
ar[i++]=*current;
current++;
}
ar[i]='\0';
current=start;
next=start;
if( !(48 <= *current && *current <= 57 ) )
{
//printf("\n Failed at state 14 in Literal transistion:");
strcpy(ftest[14],"Failed at state 14:");
fail[14]=TRUE;
//ftest[strlen("Failed at state 14:")]='\0';
//addddddd
lit_t=FALSE;
}
if(*current=='-')
negative=TRUE;
current +=1;
next=current;
ide_len++;
while(*current!= ' ' && *current !='\0' && lit_t==TRUE)
{
if((48 <= *current && *current <= 57 ))
{
state++;
}
else
{
//printf("\n Failed at state 15:");
strcpy(ftest[15],"Failed at state 15:");
fail[15]=TRUE;
//ftest[strlen("Failed at state 15:")]='\0';
if(*current!='.')
{
j++;
lit_t=FALSE;
}
else
lit_t=FALSE;
//break;
}
current++;
}
if(lit_t==FALSE )
{
if(negative==TRUE && lit_t==TRUE)
{
printf("\n %s\t\t Out of range:",ar);
lit=TRUE;
}
else
lit=FALSE;
}//printf("\n %s is Invalid identifier:",ar);
else
{
numb=atoi(ar);
if(numb <=0 || numb >999)
{
printf("\n %s\t\t Out of range:",ar);
lit=TRUE;
}
else {
lit=TRUE;
printf("\n %s\t\t Constant:",ar);
printf("\n %c\t\t14(s)------->15",ar[0]);
for(i=1;i<=state;i++)
printf("\n %c\t\t15------->15",ar[i]);
printf("\n *D\t\t15------->16");
printf("\n");

}
}
} // end of if for literal trans
//start of transistion of operators
i=0;
if(key==FALSE && lit==FALSE && ide==FALSE)// && negative == FALSE)
{
//printf("\n in OPERATORSSSSSSSSSSSSSSSSSS");
strcpy(ar,"");
current=start;
next=current;
ar[0]=*current;
//    printf("\n>>>>>>>>> %c",*current);
switch(*current)
{
case '+':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
ope=TRUE;
current=next;
ope_final[0]=TRUE;
}
else
{
//printf("\n Failed at state 18:");
strcpy(ftest[18],"Failed at state 18:");
fail[18]=TRUE;
//ftest[strlen("Failed at state 18:")]='\0';
ope=FALSE;
}
break;
case '-':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
ope=TRUE;
current=next;
ope_final[1]=TRUE;
}
else
{
//printf("\n Failed at state 20:");
if((48<= *next && *next <= 57))
{
//printf("\n Failed at state 20:  %c",*next);
strcpy(ftest[20],"Failed at state 20:");
fail[20]=FALSE;
//ftest[strlen("Failed at state 20:")]='\0';
ope=FALSE;
}
else
{
          printf("\n Failed at state 20:  %c",*next);
strcpy(ftest[20],"Failed at state 20:");
fail[20]=TRUE;
//ftest[strlen("Failed at state 20:")]='\0';
ope=FALSE;
}
}
break;
case '*':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
ope=TRUE;
current=next;
ope_final[2]=TRUE;
}
else
{
//printf("\n Failed at state 22:");
strcpy(ftest[22],"Failed at state 22:");
fail[22]=TRUE;
//ftest[strlen("Failed at state 22:")]='\0';
ope=FALSE;
}
break;
case '/':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
ope=TRUE;
current=next;
ope_final[3]=TRUE;
}
else
{
//printf("\n Failed at state 24:");
strcpy(ftest[24],"Failed at state 24:");
fail[24]=TRUE;
//ftest[strlen("Failed at state 24:")]='\0';
ope=FALSE;
}
break;
case '=':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
ope=TRUE;
current=next;
ope_final[4]=TRUE;
}
else
{
//printf("\n Failed at state 26:");
strcpy(ftest[26],"Failed at state 26:");
fail[26]=TRUE;
//ftest[strlen("Failed at state 26:")]='\0';
ope=FALSE;
}
break;
case '>':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
ope=TRUE;
current=next;
ope_final[5]=TRUE;
}
else
{
//printf("\n Failed at state 28:");
strcpy(ftest[28],"Failed at state 28:");
fail[28]=TRUE;
//ftest[strlen("Failed at state 28:")]='\0';
ope=FALSE;
}
break;
case '<':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
ope=TRUE;
current=next;
ope_final[6]=TRUE;
}
else
{
//printf("\n Failed at state 30:");
strcpy(ftest[30],"Failed at state 30:");
fail[30]=TRUE;
//ftest[strlen("Failed at state 30:")]='\0';
ope=FALSE;
}
break;
default:
ope=FALSE;
//printf("\n Failed at state 17 in operator transistion:");
strcpy(ftest[17],"Failed at state 17:");
fail[17]=TRUE;
//ftest[strlen("Failed at state 17:")]='\0';
break;
}// end of switch
if(ope==TRUE)
printf("\n %s\t\t Operator",ar);
else
{}//printf("\n %s\t\t is an Invalid Token:",ar);
}     // end of if for operator transisition
// State Table for operators
for(i=0;i<7;i++)
{
if(ope_final[i]==TRUE)
{
printf("\n %s\t\t 17(s)------>%d",ar,18+i*2);
printf("\n *D\t\t %d--------->%d(f)",18+i*2,(18+i*2)+1);
printf("\n");
}
}
// start of transistion for symbols
if(key==FALSE && lit==FALSE && ide==FALSE && ope==FALSE)// && negative == TRUE)
{
//printf("\n in SYMBOLSSSSSSSSSSSSSSSSS");
strcpy(ar,"");
current=start;
next=current;
ar[0]=*current;
//    printf("\n>>>>>>>>> %c",*current);
switch(*current)
{
case '{':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
symb=TRUE;
current=next;
sym_final[0]=TRUE;
}
else
{
//printf("\n Failed at state 33:");
strcpy(ftest[33],"Failed at state 33:");
fail[33]=TRUE;
//ftest[strlen("Failed at state 33:")]='\0';
symb=FALSE;
}
break;
case ',':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
ope=TRUE;
current=next;
sym_final[1]=TRUE;
}
else
{
//printf("\n Failed at state 35:");
strcpy(ftest[35],"Failed at state 35:");
fail[35]=TRUE;
//ftest[strlen("Failed at state 35:")]='\0';
symb=FALSE;
}
break;
case '(':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
symb=TRUE;
current=next;
sym_final[2]=TRUE;
}
else
{
//printf("\n Failed at state 37:");
strcpy(ftest[37],"Failed at state 37:");
fail[37]=TRUE;
//ftest[strlen("Failed at state 37:")]='\0';
symb=FALSE;
}
break;
case ')':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
symb=TRUE;
current=next;
sym_final[3]=TRUE;
}
else
{
//printf("\n Failed at state 39:");
strcpy(ftest[39],"Failed at state 39:");
fail[39]=TRUE;
//ftest[strlen("Failed at state 39:")]='\0';
ope=FALSE;
}
break;
case ';':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
symb=TRUE;
current=next;
sym_final[4]=TRUE;
}
else
{
//printf("\n Failed at state 41:");
strcpy(ftest[41],"Failed at state 41:");
fail[41]=TRUE;
//ftest[strlen("Failed at state 41:")]='\0';
symb=FALSE;
}
break;
case '?':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
symb=TRUE;
current=next;
sym_final[5]=TRUE;
}
else
{
//printf("\n Failed at state 43:");
strcpy(ftest[43],"Failed at state 43:");
fail[43]=TRUE;
//ftest[strlen("Failed at state 43:")]='\0';
symb=FALSE;
}
break;
case '<':
next +=1;
if(*next ==' ' || *next=='\0')
{
ar[1]='\0';
symb=TRUE;
current=next;
sym_final[6]=TRUE;
}
else
{
 // printf("\n Failed at state 30:");
symb=FALSE;
}
break;
default:
symb=FALSE;
//printf("\n Failed at state 32 in operator transistion:");
strcpy(ftest[32],"Failed at state 32:");
fail[32]=TRUE;
//ftest[strlen("Failed at state 32:")]='\0';
break;
}// end of switch
if(symb==TRUE)
printf("\n %s\t\t Symbol",ar);
else
{
if(atof(ar) || ar[0]=='0')
{
if(lit_t==FALSE && j>=1)
printf("\n %s\t\t is an Invalid Identifier:",ar);
else
printf("\n %s\t\t is an Invalid Constant:",ar);
}
else
printf("\n %s\t\t is an Invalid Token:",ar);
}
}              // end of if for symbol transistion
//printf("\ncurrent =[%c]",*current);
// State table for Symbols
for(i=0;i<7;i++)
{
if(sym_final[i]==TRUE)
{
printf("\n %s\t\t 32(s)------>%d",ar,33+i*2);
printf("\n *D\t\t %d--------->%d(f)",33+i*2,(33+i*2)+1);
printf("\n");
}
}
// Display failed states
printf("\n Want to see the failed states in different transistion 1/2:");
scanf("%d",&choice);
switch(choice)
{
case 1:
for(i=0;i<45;i++)
if(fail[i]==TRUE)
printf("\n%s",ftest[i]);
break;
case 2:
default:
break;
}
// variables resetting
for(i=0;i<11;i++)
iden_final[i]=FALSE;
for(i=0;i<7;i++)
ope_final[i]=sym_final[i]=FALSE;
for(i=0;i<45;i++)
fail[i]=FALSE;
key=TRUE;
ide_len=0;
ide=TRUE;
ide_t=TRUE;
lit=TRUE;
lit_t=TRUE;
ope=TRUE;
symb=TRUE;
negative=FALSE;
strcpy(ar,"");
printf("\n");
current=start;
next=current;
//printf("\n current =[%c]",*current);
do
{
if(*current=='\0' || *current=='\n')
break;

 // printf("\n current(loop) =[%c]",*current);
current++;
} while(*current!=' ');
do
{
if(*current=='\0' || *current=='\n')
break;

  // printf("\n current(loop) =[%c]",*current);
current++;
} while(*current==' ');
//printf("\n after current =[%c]",*current);
if(*current=='\0' || *current=='\n')
break;
next=current;
start=current;
super=current;
//printf("\n super =[%c]",*super);
if(*super=='\0' || *super =='\n' || *super ==' ')
break;
} // one token classification
return 0;
}