/* words3.c
 *
 * A (largish) input buffer takes the input,
 * then once the word size is known, the space
 * for that word is allocated on the heap.
 *
 * The list of words is stored in the stack
 * as a (fixed size) list of pointers.
 * 
 * The heap memory is not freed until the program exits.
 *
 *   $ gcc words3.c -o words3
 *   $ ./words3
 *   Input your words, one per line, with a blank line to stop.
 *   > one
 *   > two
 *   > three
 *   > 
 *   The words are ['one', 'two', 'three'].
 *   Done.
 *
 * Jim Mahoney | Feb 2013 | MIT License
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
#define MAX_INPUT 100
#define MAX_WORDS 10

// Read a word into the input buffer.
// Then allocate memory on the heap for that word,
// copy it over, and return a pointer to it. 
char* read_word(char* buffer){
  char* status = fgets(buffer, MAX_INPUT, stdin);
  char* word;
  int length;
  if (status == NULL){
    printf("READ ERROR - fgets returned NULL\n");
    exit(1);
  }
  length = strlen(buffer);
  if (buffer[length - 1] == '\n'){      // remove trailing newline
    buffer[length - 1] = (char) 0;
    length--;
  }
  word = malloc(length + 1);            // new memory (+1 for trailing 0)
  strcpy(word, buffer);                 // copy input to new string
  return word;
}

int main(){
  char buffer[MAX_INPUT];              // input space for one word
  char* list[MAX_WORDS];               // list of pointers
  int n, i;

  printf("Input your words, one per line, with a blank line to stop.\n");
  n = 0;                               // current word (i.e. row) index
  while (n < MAX_WORDS){
    printf("> ");
    list[n] = read_word(buffer);
    if (strlen(list[n]) == 0) break;   // blank line stops reading
    n++;
  }
  
  printf("The words are [");
  for (i=0; i < n; i++){
    printf("'%s'", list[i]);
    if (i != n - 1) printf(", ");
  }
  printf("].\nDone.\n");

  return 0;
}