alsa-visual/spark_ncurses.c

#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <ncurses.h>
#include <sys/ioctl.h>
#include <ctype.h>

#define NARGS 1024
#define ARG_SIZE 50

int args;
int values[NARGS + 1];

struct winsize ws;

int add_value(const char *str) {
	if (args >= sizeof(values) / sizeof(int) || args > ws.ws_col)
		return 1;

	values[args] = atoi(str);
	args++;

	return 0;
}

void stdin_read(void) {
	char arg[ARG_SIZE + 1];
	char *p = arg;

	while (1) {
		int c = getchar();
		if (c == EOF)
			return;

		else if (c == ' ' && p != arg) {
			*p = '\0';
			p = arg;

			if (add_value(arg))
				break;
		}

		else {
			*p = c;
			if (p + 1 == arg + sizeof(arg))
				break;

			p++;
		}
	}
}

void sig_handler(int sig) {
	(void)sig;

	endwin();
	exit(0);
}

void print(int y, int x, char *str, int val) {
	if (val < 0)
		mvprintw(y, x, "%s", str);

	else
		mvprintw(y, x, "%s", str);
}

int main(void) {
	signal(SIGINT, sig_handler);
	signal(SIGTERM, sig_handler);
	if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) < 0)
		return 1;

	initscr();
	noecho();
	curs_set(0);
	timeout(0);

	int min = 0;
	int max = 0;

	int middle = ws.ws_row / 2;
	while (1) {
		args = 0;
		stdin_read();

		clear();
		for (int i = 0; i < args; i++) {
			int val = values[i];
			if (val < 0)
				val *= -1;

			if (val < min)
				min = val;

			else if (val > max)
				max = val;

			int lvl = (val - min) * (ws.ws_row / 5) / ((max - min) + 1);
			for (int j = 0; j < lvl; j++) {
				print(middle - j, i, "$", values[i]);
				print(middle + j, i, "$", values[i]);
			}

			print(middle - lvl, i, ".", values[i]);
			print(middle + lvl, i, "'", values[i]);
		}

		refresh();
	}
}