Thread: Printing a Character from Binary

As far as I know, there isn't any standard function to handle this. The code for such a function, however, isn't too terribly complicated...

Code:

int atob (const char * intMe)
{
 int result = 0;
 int i;
 for (i = 0; intMe[i] != '\0'; i++)
 {
  result <<= 1; // Shift the values in result left once.  Same ase
    // result *= 2;

  // if intMe[i] == '0', we don't do anything.
  if (intMe[i] == '1')
  {
   result += 1;
  }
 }

 return result;
}

Check this!
If you e-mail me I could send some source code to you I´m writing at the moment which does exactly the same.
Because I have hardly time for programming at the moment, it will last about a week until I have finished it.

klausi

Here is my solution now. Finished it yesterday:

Code:

#include <stdio.h>
#include <stdlib.h> /* for allocating memory for the strings */

#define PUFFER 256

int lenof(char *str); /* returns the length of a string inclusive the ending '\0' */
void asctobin(void); /* converts ASCII-characters into binary digits */
void bintoasc(void); /* converts binary digits into ASCII characters */

unsigned char bin[]={1,2,4,8,16,32,64,128}; /* bitfield */


int main(void)
{
	char chose;

	for(chose=0;chose<50;chose++,printf("\n")) ; /* Clear screen */

again:
	printf("Enter \'A\' to convert ASCII to binary or \'B\' to convert binary into ASCII: ");
	scanf("%c",&chose);
	if(chose=='A' || chose=='a') asctobin();
	else
	{
		if(chose=='B' || chose=='b') bintoasc();
		else{
			rewind(stdin); /* back to the begin of stdin; if more then one character was entered */
goto again;} /* only accepts 'A','a','B' and 'b' as inputs */
	}

	return 0;
}


void asctobin(void)
{
        char *string,c;
	int count,len;

	if((string=(char*)malloc(PUFFER))==NULL)
	{
		printf("Cannot allocate enough memory!");
		exit(1); /* exit with the return code an error */
	}


	printf("Enter string (max length: 255 characters): ");
	rewind(stdin); /* back to the begin of stdin */
        fgets(string,PUFFER-1,stdin);

	len=lenof(string);

	for(;len>1;len--) /* as often as the value for the length of the inputed string */
	{
		c=*string; /* the character *string points to at the moment */
		for(count=7;count>=0;count--)
		{        
			if(c>=bin[count])
			{
				printf("1");
				c-=bin[count];
			}else
			printf("0");
		}
		*string++;
		printf(" ");
	}
}


int lenof(char *str)
{
	int count=0;

	while(*str!='\0' && count<256)
	{
		*str++;
		count++;
	}

	return(count);
}


void bintoasc(void)
{
	char *string,c;
	int count=0,len;

	if((string=(char*)malloc(PUFFER))==NULL)
	{
		printf("Cannot allocate enough memory!");
		exit(1); /* exit with the return code for an error */
	}


	printf("Enter digits (max 255):");
	rewind(stdin); /* back to the begin of stdin */
        fgets(string,PUFFER-1,stdin);

	len=lenof(string);

	for(;len>1;len--) /* as often as the value for the length of the inputed string */
	{
		if(*string=='1')
		{
			c+=bin[7-count];
			count++;
		}else 
		if(*string=='0') count++;

		if(count%8==0)
		{
			printf("%c",c);
			count=c=0;
		}

		*string++;
	}
}

klausi

Could you occassionally give some comments about my programming style?
It´s actually my second program I wrote in C.
Maybe you can also give some better comments than I wrote into the program.
I programmed the function lenof() on myself, because I think it´s more efficient than including the string library.

klausi