svn commit: r335739 - in stable/11/usr.bin/seq: . tests

[Kyle Evans]

Author: kevans
Date: Wed Jun 27 21:03:05 2018
New Revision: 335739
URL: https://svnweb.freebsd.org/changeset/base/335739

Log:
  MFC r330086, r333155: seq(1) improvements
  
  MFC r330086 (cem): seq(1): Consistently include 'last' for non-integers
  
  The source of error is a rounded increment being too large and thus the loop
  steps slightly past 'last'.  Perform a final comparison using the formatted
  string values (truncated precision) to determine if we still need to print
  the 'last' value.
  
  MFC r333155: seq(1): Move long_opts up with globals
  
  PR:		217149

Added:
  stable/11/usr.bin/seq/tests/
     - copied from r330086, head/usr.bin/seq/tests/
Modified:
  stable/11/usr.bin/seq/Makefile
  stable/11/usr.bin/seq/seq.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/usr.bin/seq/Makefile
==============================================================================
--- stable/11/usr.bin/seq/Makefile	Wed Jun 27 21:00:09 2018	(r335738)
+++ stable/11/usr.bin/seq/Makefile	Wed Jun 27 21:03:05 2018	(r335739)
@@ -1,8 +1,13 @@
 #       $NetBSD: Makefile,v 1.3 2009/04/14 22:15:26 lukem Exp $
 # $FreeBSD$
 
+.include <src.opts.mk>
+
 PROG=	seq
 
 LIBADD=	m
+
+HAS_TESTS=
+SUBDIR.${MK_TESTS}+=	tests
 
 .include <bsd.prog.mk>

Modified: stable/11/usr.bin/seq/seq.c
==============================================================================
--- stable/11/usr.bin/seq/seq.c	Wed Jun 27 21:00:09 2018	(r335738)
+++ stable/11/usr.bin/seq/seq.c	Wed Jun 27 21:03:05 2018	(r335739)
@@ -57,6 +57,15 @@ __FBSDID("$FreeBSD$");
 static const char *decimal_point = ".";	/* default */
 static char default_format[] = { "%g" };	/* default */
 
+static const struct option long_opts[] =
+{
+	{"format",	required_argument,	NULL, 'f'},
+	{"separator",	required_argument,	NULL, 's'},
+	{"terminator",	required_argument,	NULL, 't'},
+	{"equal-width",	no_argument,		NULL, 'w'},
+	{NULL,		no_argument,		NULL, 0}
+};
+
 /* Prototypes */
 
 static double e_atof(const char *);
@@ -68,15 +77,6 @@ static int valid_format(const char *);
 static char *generate_format(double, double, double, int, char);
 static char *unescape(char *);
 
-static const struct option long_opts[] =
-{
-	{"format",	required_argument,	NULL, 'f'},
-	{"separator",	required_argument,	NULL, 's'},
-	{"terminator",	required_argument,	NULL, 't'},
-	{"equal-width",	no_argument,		NULL, 'w'},
-	{NULL,		no_argument,		NULL, 0}
-};
-
 /*
  * The seq command will print out a numeric sequence from 1, the default,
  * to a user specified upper limit by 1.  The lower bound and increment
@@ -86,17 +86,20 @@ static const struct option long_opts[] =
 int
 main(int argc, char *argv[])
 {
-	int c = 0, errflg = 0;
-	int equalize = 0;
-	double first = 1.0;
-	double last = 0.0;
-	double incr = 0.0;
+	const char *sep, *term;
 	struct lconv *locale;
-	char *fmt = NULL;
-	const char *sep = "\n";
-	const char *term = NULL;
-	char pad = ZERO;
+	char pad, *fmt, *cur_print, *last_print;
+	double first, last, incr, last_shown_value, cur, step;
+	int c, errflg, equalize;
 
+	pad = ZERO;
+	fmt = NULL;
+	first = 1.0;
+	last = incr = last_shown_value = 0.0;
+	c = errflg = equalize = 0;
+	sep = "\n";
+	term = NULL;
+
 	/* Determine the locale's decimal point. */
 	locale = localeconv();
 	if (locale && locale->decimal_point && locale->decimal_point[0] != '\0')
@@ -179,17 +182,32 @@ main(int argc, char *argv[])
 	} else
 		fmt = generate_format(first, incr, last, equalize, pad);
 
-	if (incr > 0) {
-		for (; first <= last; first += incr) {
-			printf(fmt, first);
-			fputs(sep, stdout);
-		}
-	} else {
-		for (; first >= last; first += incr) {
-			printf(fmt, first);
-			fputs(sep, stdout);
-		}
+	for (step = 1, cur = first; incr > 0 ? cur <= last : cur >= last;
+	    cur = first + incr * step++) {
+		printf(fmt, cur);
+		fputs(sep, stdout);
+		last_shown_value = cur;
 	}
+
+	/*
+	 * Did we miss the last value of the range in the loop above?
+	 *
+	 * We might have, so check if the printable version of the last
+	 * computed value ('cur') and desired 'last' value are equal.  If they
+	 * are equal after formatting truncation, but 'cur' and
+	 * 'last_shown_value' are not equal, it means the exit condition of the
+	 * loop held true due to a rounding error and we still need to print
+	 * 'last'.
+	 */
+	asprintf(&cur_print, fmt, cur);
+	asprintf(&last_print, fmt, last);
+	if (strcmp(cur_print, last_print) == 0 && cur != last_shown_value) {
+		fputs(last_print, stdout);
+		fputs(sep, stdout);
+	}
+	free(cur_print);
+	free(last_print);
+
 	if (term != NULL)
 		fputs(term, stdout);