/*
 * Program to count total characters in one or more files, and
 * also "text" characters (printable and not space).
 * Displays counts for each file individually and totals.
 * Filenames are given as command-line arguments, e.g., if the
 * program's name is the default a.out:
 *
 * a.out infile1 infile2 
 *
 * Somewhat silly but an example of processing one or more files,
 * and of using character functions.
 */
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>

/*
 * count characters (all and "text") in file.
 * prints error message if file could not be opened.
 * otherwise prints counts for this file and then adds them
 * to global totals in *total_chars and *text_chars.
 */
void count_chars(char *filename, long *total_chars, long *text_chars);

/* main program */
int main(int argc, char* argv[]) {
	long total_chars = 0;
	long text_chars = 0;
	if (argc < 2) {
		printf("usage:  %s filename1 ....\n", argv[0]);
		return EXIT_FAILURE; /* portable way to return error status */
	}
	for (int i = 1; i < argc; i++) {
		count_chars(argv[i], &total_chars, &text_chars);
	}
	printf("totals:  %ld characters, %ld text characters\n",
			total_chars, text_chars);
	return EXIT_SUCCESS; /* portable way to return no-error status */
}

void count_chars(char *filename, long *total_chars, long *text_chars) {
	FILE * infile = fopen(filename, "r");
	if (infile == NULL) {
		printf("could not open file %s\n", filename);
	}
	else {
		/* compute counts for this file */
		long total_c = 0;
		long text_c = 0;
		int inchar;
		while ((inchar = fgetc(infile)) != EOF) {
			++total_c;
			if (isprint(inchar) && !isspace(inchar)) {
				text_c++;
			}
		}
		fclose(infile);
		printf("%s has %ld characters, %ld text characters\n",
				filename, total_c, text_c);
		/* update totals */
		(*total_chars) += total_c;
		(*text_chars) += text_c;
	}
}