From 40560618aa165add94a80f70d2b187546ed47cfe Mon Sep 17 00:00:00 2001
From: Charles Cabergs <me@cacharle.xyz>
Date: Sat, 8 Aug 2020 15:43:48 +0200
Subject: Added seq

---
 seq/seq.c | 126 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 126 insertions(+)
 create mode 100644 seq/seq.c

diff --git a/seq/seq.c b/seq/seq.c
new file mode 100644
index 0000000..8307fc4
--- /dev/null
+++ b/seq/seq.c
@@ -0,0 +1,126 @@
+#define _POSIX_C_SOURCE 2
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <errno.h>
+#include <string.h>
+#include <ctype.h>
+
+#define MAX(x, y) ((x) > (y) ? (x) : (y))
+
+typedef struct
+{
+	long double	value;
+	int			precision;
+	int			integer_len;
+}				t_num;
+
+char			*g_name = "seq";
+
+int				parse_num(char *s, t_num *num)
+{
+	char	*tmp;
+
+	errno = 0;
+	num->value = strtold(s, &tmp);
+	if (errno != 0 || *tmp != '\0')
+	{
+		fprintf(stderr, "%s: invalid floating point argument: '%s'\n", g_name, s);
+		exit(EXIT_FAILURE);
+	}
+	num->precision = 0;
+	num->integer_len = strlen(s);
+	if ((tmp = strchr(s, '.')) != NULL)
+	{
+		num->precision = strlen(tmp + 1);
+		num->integer_len = tmp - s;
+	}
+	return 0;
+}
+
+int				main(int argc, char **argv)
+{
+	if (argc == 1)
+	{
+		fprintf(stderr, "%s: missing operand\n", argv[0]);
+		return EXIT_FAILURE;
+	}
+
+	int		option;
+	char	*separator = "\n";
+	bool	padding = false;
+
+	g_name = argv[0];
+
+	while ((option = getopt(argc, argv, "f:s:w0123456789")) != -1)
+	{
+		if (isdigit(option))
+			break;
+		switch (option)
+		{
+			case 'f':
+				exit(EXIT_FAILURE); // TODO
+				break;
+			case 's':
+				separator = optarg;
+				break;
+			case 'w':
+				padding = true;
+				break;
+		}
+	}
+
+	t_num first;
+	t_num increment;
+	t_num last;
+
+	first.value = 1.0;
+	first.precision = 0;
+	increment.value = 1.0;
+	increment.precision = 0;
+
+	switch (argc - optind)
+	{
+		case 1:
+			parse_num(argv[optind], &last);
+			break;
+		case 2:
+			parse_num(argv[optind], &first);
+			parse_num(argv[optind + 1], &last);
+			break;
+		case 3:
+			parse_num(argv[optind], &first);
+			parse_num(argv[optind + 1], &increment);
+			if (increment.value == 0)
+			{
+				fprintf(stderr, "%s: invalid Zero increment value '%s'\n", argv[0], argv[optind + 3]);
+				exit(EXIT_FAILURE);
+			}
+			parse_num(argv[optind + 2], &last);
+			break;
+		default:
+			fprintf(stderr, "%s: extra operand '%s'\n", argv[0], argv[optind + 3]);
+			exit(EXIT_FAILURE);
+			break;
+	}
+
+	while (increment.value > 0 ? (first.value <= last.value) : (first.value >= last.value))
+	{
+		int precision = MAX(first.precision, increment.precision);
+		if (!padding)
+			printf("%.*llf", precision, first.value);
+		else
+		{
+			int width = MAX(last.integer_len, first.integer_len);
+			if (precision != 0)
+				width += precision + 1;
+			printf("%0*.*llf", width, precision, first.value);
+		}
+		first.value += increment.value;
+		if (increment.value > 0 ? (first.value <= last.value) : (first.value >= last.value))
+			fputs(separator, stdout);
+	}
+	putchar('\n');
+	return EXIT_SUCCESS;
+}
-- 
cgit