progress(): Very simple ASCII progress bar from troglobit/toolbox@f98c5d0

This patch adds a very simple progress bar I wrote once.  It's revision
f98c5d0 from https://github.com/troglobit/toolbox

Also included in this patch is conio.h, a neat little set of macros for
manipulating your terminal using ANSI escape seequences.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

progress.c

@@ -0,0 +1,102 @@
+/* Very simple termios based progress bar
+ *
+ * Copyright (c) 2012, 2013  Joachim Nilsson <troglobit@gmail.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <limits.h>		/* INT_MAX */
+#include <stdio.h>
+
+#include "conio.h"
+
+static char spinner(void)
+{
+	static int i = INT_MAX;
+	char *states = "|/-\\";
+//	char *states = ".oOo";
+//	char *states = ".oO°Oo.";
+//	char *states = "v<^>";
+//	char *states = ".oO@*";
+
+	/* Subtract to get clockwise spinning. */
+	return states[i-- % 4];	/* % Number of states */
+}
+
+void progress(int percent, int max_width)
+{
+	int i, bar = percent * max_width / 100;
+
+	if (0 == percent)
+		hidecursor();
+
+	fprintf(stderr, "\r%3d%% %c [", percent, spinner());
+
+	for (i = 0; i < max_width; i++) {
+		if (i > bar)
+			fputc(' ', stderr);
+		else if (i == bar)
+			fputc('>', stderr);
+		else
+			fputc('=', stderr);
+	}
+
+	fprintf(stderr, "]");
+	if (100 == percent) {
+		showcursor();
+		fputc('\n', stderr);
+	}
+}
+
+#ifdef UNITTEST
+#include <stdlib.h>		/* atexit() */
+#include <unistd.h>		/* usleep() */
+
+#define MAX_WIDTH    80
+#define msleep(msec) usleep(msec * 1000)
+
+static void bye(void)
+{
+	showcursor();
+}
+
+int main(int argc __attribute__((unused)), char const *argv[] __attribute__((unused)))
+{
+	int i, percent, block = 0, num = 85;
+
+	atexit(bye);
+	hidecursor();
+
+	while (block < num) {
+		percent = block * 100 / num;
+		for (i = 0; i < 10; i++) {
+			progress(percent, MAX_WIDTH);
+			msleep(2);
+		}
+		block++;
+		msleep(50);
+	}
+	progress(100, MAX_WIDTH);
+
+	return 0;
+}
+#endif	/* UNITTEST */
+
+/**
+ * Local Variables:
+ *  compile-command: "gcc -g -I../../include -o unittest -DUNITTEST progress.c; and ./unittest"
+ *  version-control: t
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */