aboutsummaryrefslogtreecommitdiff
path: root/stdio-common/tst-printf-round.c
diff options
context:
space:
mode:
authorJoseph Myers <joseph@codesourcery.com>2012-09-14 20:18:49 +0000
committerJoseph Myers <joseph@codesourcery.com>2012-09-14 20:18:49 +0000
commit784761bee3828e4e21cbe15340c7a99e3fd1788b (patch)
treeed600795b4bcfd6558aa48850ee1f2f7b2e0a715 /stdio-common/tst-printf-round.c
parent01e80428f7df1a91de2f16ee632e81bc41a17d40 (diff)
downloadglibc-784761bee3828e4e21cbe15340c7a99e3fd1788b.zip
glibc-784761bee3828e4e21cbe15340c7a99e3fd1788b.tar.gz
glibc-784761bee3828e4e21cbe15340c7a99e3fd1788b.tar.bz2
Make printf respect the rounding mode for decimal output (bug 5044).
Diffstat (limited to 'stdio-common/tst-printf-round.c')
-rw-r--r--stdio-common/tst-printf-round.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/stdio-common/tst-printf-round.c b/stdio-common/tst-printf-round.c
new file mode 100644
index 0000000..2bd4607
--- /dev/null
+++ b/stdio-common/tst-printf-round.c
@@ -0,0 +1,110 @@
+/* Test for correct rounding of printf floating-point output.
+ Copyright (C) 2012 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <fenv.h>
+#include <stdio.h>
+#include <string.h>
+
+struct dec_test {
+ double d;
+ const char *fmt;
+ const char *rd, *rn, *rz, *ru;
+};
+
+static const struct dec_test dec_tests[] = {
+ { 1.5, "%.0f", "1", "2", "1", "2" },
+ { -1.5, "%.0f", "-2", "-2", "-1", "-1" },
+ { 2.5, "%.0f", "2", "2", "2", "3" },
+ { -2.5, "%.0f", "-3", "-2", "-2", "-2" },
+ { 1.4999, "%.0f", "1", "1", "1", "2" },
+ { -1.4999, "%.0f", "-2", "-1", "-1", "-1" },
+ { 1.5001, "%.0f", "1", "2", "1", "2" },
+ { -1.5001, "%.0f", "-2", "-2", "-1", "-1" },
+ { 2.4999, "%.0f", "2", "2", "2", "3" },
+ { -2.4999, "%.0f", "-3", "-2", "-2", "-2" },
+ { 2.5001, "%.0f", "2", "3", "2", "3" },
+ { -2.5001, "%.0f", "-3", "-3", "-2", "-2" },
+ { 1.0 / 3.0, "%f", "0.333333", "0.333333", "0.333333", "0.333334" },
+ { -1.0 / 3.0, "%f", "-0.333334", "-0.333333", "-0.333333", "-0.333333" },
+ { 0.2500001, "%.2e", "2.50e-01", "2.50e-01", "2.50e-01", "2.51e-01" },
+ { -0.2500001, "%.2e", "-2.51e-01", "-2.50e-01", "-2.50e-01", "-2.50e-01" },
+ { 1000001.0, "%.1e", "1.0e+06", "1.0e+06", "1.0e+06", "1.1e+06" },
+ { -1000001.0, "%.1e", "-1.1e+06", "-1.0e+06", "-1.0e+06", "-1.0e+06" },
+};
+
+static int
+test_dec_in_one_mode (double d, const char *fmt, const char *expected,
+ const char *mode_name)
+{
+ char buf[100];
+ int ret = snprintf (buf, sizeof buf, fmt, d);
+ if (ret <= 0 || ret >= (int) sizeof buf)
+ {
+ printf ("snprintf for %a returned %d\n", d, ret);
+ return 1;
+ }
+ if (strcmp (buf, expected) == 0)
+ return 0;
+ else
+ {
+ printf ("snprintf (\"%s\", %a) returned \"%s\" not \"%s\" (%s)\n",
+ fmt, d, buf, expected, mode_name);
+ return 1;
+ }
+}
+
+static int
+do_test (void)
+{
+ int save_round_mode = fegetround ();
+ int result = 0;
+
+ for (size_t i = 0; i < sizeof (dec_tests) / sizeof (dec_tests[0]); i++)
+ {
+ result |= test_dec_in_one_mode (dec_tests[i].d, dec_tests[i].fmt,
+ dec_tests[i].rn, "default rounding mode");
+#ifdef FE_DOWNWARD
+ if (!fesetround (FE_DOWNWARD))
+ {
+ result |= test_dec_in_one_mode (dec_tests[i].d, dec_tests[i].fmt,
+ dec_tests[i].rd, "FE_DOWNWARD");
+ fesetround (save_round_mode);
+ }
+#endif
+#ifdef FE_TOWARDZERO
+ if (!fesetround (FE_TOWARDZERO))
+ {
+ result |= test_dec_in_one_mode (dec_tests[i].d, dec_tests[i].fmt,
+ dec_tests[i].rz, "FE_TOWARDZERO");
+ fesetround (save_round_mode);
+ }
+#endif
+#ifdef FE_UPWARD
+ if (!fesetround (FE_UPWARD))
+ {
+ result |= test_dec_in_one_mode (dec_tests[i].d, dec_tests[i].fmt,
+ dec_tests[i].ru, "FE_UPWARD");
+ fesetround (save_round_mode);
+ }
+#endif
+ }
+ return result;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"