/*
 *  getline.c - Count characters per-line from stdin. Strips white
 *              space from end of line, and ignores 0-length lines.
 *
 *  Author: Ryan R. Uber <ryan@blankbmx.com>
 *  Date:   31 Oct 2010 04:28:47PM CDT
 *
 *  Modified from section 1.9 (Character Arrays)
 *  "The C Programming Language" by Brian Kerrigan and Dennis Ritchie
 *
 */

#include <stdio.h>
#define MAXLINE 1000

/*  Here we initialize getline(). I am unclear on why it is initialized
 *  at the top of the file with different arguments than the actual
 *  function. It works identically without this initialization.
 */
int getline(char line[], int maxline);

main()
{
    int len;
    char line[MAXLINE];

    /*  Gather lines that have a non-zero length. This would include *any*
     *  line in a file, even a blank line, as that would have a length of
     *  1 for the '\n' character.
     */
    while ((len = getline(line, MAXLINE)) > 0 )
    {
        /*  As stated previously, a blank line has a length of 1. Therefore,
         *  in order to skip empty lines, we only want to look at lines with
         *  length of 2 or greater.
         */
        if ( len > 1 )
            printf("%6d %s", len-1, line);
    }

    return 0;
}

int getline(char s[], int lim)
{
    int c, i, n;

    for ( i=0; i < lim-1 && (c=getchar()) != EOF && c != '\n'; ++i )
        s[i] = c;

    if ( c == '\n' )
    {
        /*  This part of the program strips the white space from the end of
         *  each line. This is tricky because we cannot do this until after
         *  the entire line of input is read, including the white space. Thus,
         *  we have to remove the white space characters from the s[] array,
         *  and decrement any counters we are using to compensate for the
         *  loss of characters. Here we loop backwards through the s[] array
         *  once a newline is encountered.
         */
        for ( n = i-1; n >= 0; n-- )
        {
            /*  The variable "n" is the previous element's offset in the array.
             *  Since we found a newline character, let's see if the character
             *  before it was white space.
             */
            if ( s[n] == ' ' || s[n] == '\t' )
            {
                /*  Here we move zero the white space element in the array and
                 *  decrement the character count variable "i".
                 */
                s[n] = '\0';
                i--;
            }

            /*  If there was no white space at the end of the string, add the
             *  newline, increment "i", and break out of the backward loop.
             */
            else
            {
                s[i] = c;
                ++i;
                break;
            }
        }

        /*  My ghetto way of fixing the 0-return on lines containing *only* '\n'.
         *  This entire function needs work so that I can remove this terribleness.
         */
        if ( i < 1 )
            i = 1;
    }

    s[i] = '\0';

    return i;
}

/* EOF */