/* hexview.c
 * by Chris Williams
 * prints out the hex values of the contents of stdin
 * use more or less to page the output
 * usage:
 * 	hexview [starting_address] [< file]
 */

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>

int main(int argc, char *argv[])
{
	int c, byte = 0, done = 0;
	unsigned int address = 0;
	unsigned char row[16];
	
	if (argc > 1)
		address = strtoul(argv[1], (char **)NULL, 0);
	
	do
	{
		c = getchar();
		if (feof(stdin))
			done = 1;
		else
			row[byte] = c;
		
		if ((done && byte != 0) || ++byte == 16) /* end of row or end of file */
		{
			int i;
			for (i = byte; i < 16; ++i)
				row[i] = 0; /* Clear remaining bytes */
			
			printf("%04X:", address>>16&0xFFFF);
			printf("%04X", address&0xFFFF);
			for (i = 0; i < 8; ++i)
				printf(" %02X", row[i]);
			printf("-");
			for (i = 8; i < 16; ++i)
				printf("%02X ", row[i]);
			for (i = 0; i < byte; ++i)
				putchar(isprint(row[i])?row[i]:'.');
			putchar('\n');
			byte = 0;
			address += 16;
		}
	} while (!done);
	
	return 0;
}