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

/***
 * Read a file into an array that is exactly the right length, and in which each line
 * is stored in a character array of exactly the right length.
 * Doing so requires two passes through the file.  Pass 1 to count the lines. Pass 2
 * to actually store
 **/

/**
 * Count the lines in a file
 * Note that in main I checked for file existence, so I do not need to do it here
 **/
int linecounter(char* filename)
{
    FILE* f = fopen(filename, "r");
    char line[256];
    int linecount=0;
    while (fgets(line, 256, f))
    {
	linecount++;
    }
    fclose(f);
    return linecount;
}

/**
 * Read the file into dynamically allocated array of dynamically allocated arrays
 * Hence, the char**
 **/
char** readfile(char* filename, int linecount)
{
    char** rtn = malloc(linecount * sizeof(char*));
    int lc=0;
    FILE* f = fopen(filename, "r");
    char line[256];
    while (fgets(line, 256, f))
    {
	int llen = strlen(line);
	char* nline = malloc((llen+1)*sizeof(char));
	strcpy(nline, line);
	rtn[lc++]=nline;
    }
    fclose(f);
    return rtn;
}


int main(int argc, char* argv[])
{
    // make sure the file really exists
    FILE* f = fopen(argv[1], "r");
    if (!f)
    {
	fprintf(stderr, "No such file\n");
	return 1;
    }
    fclose(f);

    //get the number of lines and read the file.
    //Yes, this could be written in one line
    // except that I need the line count later
    int linecount = linecounter(argv[1]);
    char** text = readfile(argv[1], linecount);

    // print the file
    for (int i=0; i<linecount; i++)
	printf(text[i]);

    // imagine lots of other stuff happening here

    // free everything that was malloc'd
    // first free the contents of the text array
    for (int i=0; i<linecount; i++)
	free(text[i]);
    // then free the tesxt array itself.
    free(text);
    
    fclose(stdin);
    fclose(stdout);
    fclose(stderr);
}