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

const int STEPSIZE = 100;

char **loadfile(char *filename, int *len);

int main(int argc, char *argv[])
{
    if(argc == 1)
    {
        fprintf(stderr, "Must supply a file name to read.\n");
        exit(1);
    }
    int i;
    int len = 0;
    char **words = loadfile(argv[1], &len);

    //display 1st 100 lines.
    printf("%d\n", len);
    for(i = 0; i < len; i++)
    {
        printf("%s\n", words[i]);
    }
    printf("Done\n");

    return (EXIT_SUCCESS);
}

char **loadfile(char *filename, int *len)
{
    FILE *fp = fopen(filename, "r");
    if(!fp)
    {
        fprintf(stderr, "Can't open %s for reading.\n", filename);
        return NULL;
    }

    int arrlen = STEPSIZE;

    //Allocate space for 100 char pointers.
    char **lines = (char**)malloc(arrlen*sizeof(char*));

    char buff[10000];
    int i = 0;

    while(fgets(buff, 10000, fp))
    {
        //Check for full array, if so, extend the array
        if(i = arrlen)
        {
            arrlen += STEPSIZE;
            char **newlines = realloc(lines, arrlen*sizeof(char*));
            if(!newlines)
            {
                fprintf(stderr, "Can't reallocate\n");
                exit(1);
            }
            lines = newlines;
        }
        // trim off \0 at the end
        buff[strlen(buff)-1] = '\0';
        //get length of buffer
        int blen = strlen(buff);

        char *str = (char*)malloc((blen+1)*sizeof(char));

        //copy string from buff to structure
        strcpy(str, buff);

        lines[i] = str;

        i++;
    }

    *len = i; //Set length of char pointers
    return lines;
}