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From: Eric Blake <eblake@redhat.com>
To: qemu-devel@nongnu.org
Cc: Hanna Czenczek <hreitz@redhat.com>
Subject: [PULL 11/21] test-cutils: Add coverage of qemu_strtod
Date: Thu,  1 Jun 2023 17:02:55 -0500	[thread overview]
Message-ID: <20230601220305.2130121-12-eblake@redhat.com> (raw)
In-Reply-To: <20230601220305.2130121-1-eblake@redhat.com>

It's hard to tweak code for consistency if I can't prove what will or
won't break from those tweaks.  Time to add unit tests for
qemu_strtod() and qemu_strtod_finite().

Among other things, I wrote a check whether we have C99 semantics for
strtod("0x1") (which MUST parse hex numbers) rather than C89 (which
must stop parsing at 'x').  These days, I suspect that is okay; but if
it fails CI checks, knowing the difference will help us decide what we
want to do about it.  Note that C2x, while not final at the time of
this patch, has been considering whether to make strtol("0b1") parse
as 1 with no slop instead of the C17 parse of 0 with slop "b1"; that
decision may also bleed over to strtod().  But for now, I didn't think
it worth adding unit tests on that front (to strtol or strtod) as
things may still change.

Likewise, there are plenty more corner cases of strtod proper that I
don't explicitly test here, but there are enough unit tests added here
that it covers all the branches reached in our wrappers.  In
particular, it demonstrates the difference on when *value is left
uninitialized, which an upcoming patch will normalize.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230522190441.64278-10-eblake@redhat.com>
---
 tests/unit/test-cutils.c | 512 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 512 insertions(+)

diff --git a/tests/unit/test-cutils.c b/tests/unit/test-cutils.c
index 20ab0ecb673..e05572cd92c 100644
--- a/tests/unit/test-cutils.c
+++ b/tests/unit/test-cutils.c
@@ -25,6 +25,8 @@
  * THE SOFTWARE.
  */

+#include <math.h>
+
 #include "qemu/osdep.h"
 #include "qemu/cutils.h"
 #include "qemu/units.h"
@@ -2789,6 +2791,487 @@ static void test_qemu_strtou64_full_erange_junk(void)
     g_assert_cmpuint(res, ==, UINT64_MAX);
 }

+static void test_qemu_strtod_simple(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* no radix or exponent */
+    str = "1";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 1.0);
+    g_assert_true(endptr == str + 1);
+
+    /* leading space and sign */
+    str = " -0.0";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, -0.0);
+    g_assert_true(signbit(res));
+    g_assert_true(endptr == str + 5);
+
+    /* fraction only */
+    str = "+.5";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 0.5);
+    g_assert_true(endptr == str + 3);
+
+    /* exponent */
+    str = "1.e+1";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 10.0);
+    g_assert_true(endptr == str + 5);
+
+    /* hex without radix */
+    str = "0x10";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 16.0);
+    g_assert_true(endptr == str + 4);
+}
+
+static void test_qemu_strtod_einval(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* empty */
+    str = "";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 0.0);
+    g_assert_false(signbit(res));
+    g_assert_true(endptr == str);
+
+    /* NULL */
+    str = NULL;
+    endptr = "random";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+    g_assert_null(endptr);
+
+    /* not recognizable */
+    str = " junk";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 0.0);
+    g_assert_false(signbit(res));
+    g_assert_true(endptr == str);
+}
+
+static void test_qemu_strtod_erange(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* overflow */
+    str = "9e999";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -ERANGE);
+    g_assert_cmpfloat(res, ==, HUGE_VAL);
+    g_assert_true(endptr == str + 5);
+
+    str = "-9e+999";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -ERANGE);
+    g_assert_cmpfloat(res, ==, -HUGE_VAL);
+    g_assert_true(endptr == str + 7);
+
+    /* underflow */
+    str = "-9e-999";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -ERANGE);
+    g_assert_cmpfloat(res, >=, -DBL_MIN);
+    g_assert_cmpfloat(res, <=, -0.0);
+    g_assert_true(signbit(res));
+    g_assert_true(endptr == str + 7);
+}
+
+static void test_qemu_strtod_nonfinite(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* infinity */
+    str = "inf";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_true(isinf(res));
+    g_assert_false(signbit(res));
+    g_assert_true(endptr == str + 3);
+
+    str = "-infinity";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_true(isinf(res));
+    g_assert_true(signbit(res));
+    g_assert_true(endptr == str + 9);
+
+    /* not a number */
+    str = " NaN";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_true(isnan(res));
+    g_assert_true(endptr == str + 4);
+}
+
+static void test_qemu_strtod_trailing(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* trailing whitespace */
+    str = "1. ";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 1.0);
+    g_assert_true(endptr == str + 2);
+
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, NULL, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 1.0);
+
+    /* trailing e is not an exponent */
+    str = ".5e";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 0.5);
+    g_assert_true(endptr == str + 2);
+
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, NULL, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 0.5);
+
+    /* trailing ( not part of long NaN */
+    str = "nan(";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_true(isnan(res));
+    g_assert_true(endptr == str + 3);
+
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, NULL, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_true(isnan(res));
+}
+
+static void test_qemu_strtod_erange_junk(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* ERANGE with trailing junk... */
+    str = "1e-999junk";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -ERANGE);
+    g_assert_cmpfloat(res, <=, DBL_MIN);
+    g_assert_cmpfloat(res, >=, 0.0);
+    g_assert_false(signbit(res));
+    g_assert_true(endptr == str + 6);
+
+    /* ...has less priority than EINVAL when full parse not possible */
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, NULL, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 0.0);
+    g_assert_false(signbit(res));
+}
+
+static void test_qemu_strtod_finite_simple(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* no radix or exponent */
+    str = "1";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 1.0);
+    g_assert_true(endptr == str + 1);
+
+    /* leading space and sign */
+    str = " -0.0";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, -0.0);
+    g_assert_true(signbit(res));
+    g_assert_true(endptr == str + 5);
+
+    /* fraction only */
+    str = "+.5";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 0.5);
+    g_assert_true(endptr == str + 3);
+
+    /* exponent */
+    str = "1.e+1";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 10.0);
+    g_assert_true(endptr == str + 5);
+
+    /* hex without radix */
+    str = "0x10";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 16.0);
+    g_assert_true(endptr == str + 4);
+}
+
+static void test_qemu_strtod_finite_einval(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* empty */
+    str = "";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+    g_assert_true(endptr == str);
+
+    /* NULL */
+    str = NULL;
+    endptr = "random";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+    g_assert_null(endptr);
+
+    /* not recognizable */
+    str = " junk";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+    g_assert_true(endptr == str);
+}
+
+static void test_qemu_strtod_finite_erange(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* overflow */
+    str = "9e999";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -ERANGE);
+    g_assert_cmpfloat(res, ==, HUGE_VAL);
+    g_assert_true(endptr == str + 5);
+
+    str = "-9e+999";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -ERANGE);
+    g_assert_cmpfloat(res, ==, -HUGE_VAL);
+    g_assert_true(endptr == str + 7);
+
+    /* underflow */
+    str = "-9e-999";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -ERANGE);
+    g_assert_cmpfloat(res, >=, -DBL_MIN);
+    g_assert_cmpfloat(res, <=, -0.0);
+    g_assert_true(signbit(res));
+    g_assert_true(endptr == str + 7);
+}
+
+static void test_qemu_strtod_finite_nonfinite(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* infinity */
+    str = "inf";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+    g_assert_true(endptr == str);
+
+    str = "-infinity";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+    g_assert_true(endptr == str);
+
+    /* not a number */
+    str = " NaN";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+    g_assert_true(endptr == str);
+}
+
+static void test_qemu_strtod_finite_trailing(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* trailing whitespace */
+    str = "1. ";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 1.0);
+    g_assert_true(endptr == str + 2);
+
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, NULL, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+
+    /* trailing e is not an exponent */
+    str = ".5e";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpfloat(res, ==, 0.5);
+    g_assert_true(endptr == str + 2);
+
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, NULL, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+
+    /* trailing ( not part of long NaN */
+    str = "nan(";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+    g_assert_true(endptr == str);
+
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, NULL, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+}
+
+static void test_qemu_strtod_finite_erange_junk(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    double res;
+
+    /* ERANGE with trailing junk... */
+    str = "1e-999junk";
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -ERANGE);
+    g_assert_cmpfloat(res, <=, DBL_MIN);
+    g_assert_cmpfloat(res, >=, 0.0);
+    g_assert_false(signbit(res));
+    g_assert_true(endptr == str + 6);
+
+    /* ...has less priority than EINVAL when full parse not possible */
+    endptr = "somewhere";
+    res = 999;
+    err = qemu_strtod_finite(str, NULL, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert_cmpfloat(res, ==, 999.0);
+}
+
 static void test_qemu_strtosz_simple(void)
 {
     const char *str;
@@ -3631,6 +4114,35 @@ int main(int argc, char **argv)
     g_test_add_func("/cutils/qemu_strtou64_full/erange_junk",
                     test_qemu_strtou64_full_erange_junk);

+    /* qemu_strtod() tests */
+    g_test_add_func("/cutils/qemu_strtod/simple",
+                    test_qemu_strtod_simple);
+    g_test_add_func("/cutils/qemu_strtod/einval",
+                    test_qemu_strtod_einval);
+    g_test_add_func("/cutils/qemu_strtod/erange",
+                    test_qemu_strtod_erange);
+    g_test_add_func("/cutils/qemu_strtod/nonfinite",
+                    test_qemu_strtod_nonfinite);
+    g_test_add_func("/cutils/qemu_strtod/trailing",
+                    test_qemu_strtod_trailing);
+    g_test_add_func("/cutils/qemu_strtod/erange_junk",
+                    test_qemu_strtod_erange_junk);
+
+    /* qemu_strtod_finite() tests */
+    g_test_add_func("/cutils/qemu_strtod_finite/simple",
+                    test_qemu_strtod_finite_simple);
+    g_test_add_func("/cutils/qemu_strtod_finite/einval",
+                    test_qemu_strtod_finite_einval);
+    g_test_add_func("/cutils/qemu_strtod_finite/erange",
+                    test_qemu_strtod_finite_erange);
+    g_test_add_func("/cutils/qemu_strtod_finite/nonfinite",
+                    test_qemu_strtod_finite_nonfinite);
+    g_test_add_func("/cutils/qemu_strtod_finite/trailing",
+                    test_qemu_strtod_finite_trailing);
+    g_test_add_func("/cutils/qemu_strtod_finite/erange_junk",
+                    test_qemu_strtod_finite_erange_junk);
+
+    /* qemu_strtosz() tests */
     g_test_add_func("/cutils/strtosz/simple",
                     test_qemu_strtosz_simple);
     g_test_add_func("/cutils/strtosz/hex",
-- 
2.40.1



  parent reply	other threads:[~2023-06-01 22:04 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-06-01 22:02 [PULL 00/21] NBD and miscellaneous patches for 2023-06-01 Eric Blake
2023-06-01 22:02 ` [PULL 01/21] iotests: Fix test 104 under NBD Eric Blake
2023-06-01 22:02 ` [PULL 02/21] qcow2: Explicit mention of padding bytes Eric Blake
2023-06-01 22:02 ` [PULL 03/21] test-cutils: Avoid g_assert in unit tests Eric Blake
2023-06-01 22:02 ` [PULL 04/21] test-cutils: Use g_assert_cmpuint where appropriate Eric Blake
2023-06-01 22:02 ` [PULL 05/21] test-cutils: Test integral qemu_strto* value on failures Eric Blake
2023-06-01 22:02 ` [PULL 06/21] test-cutils: Test more integer corner cases Eric Blake
2023-06-02 12:34   ` Eric Blake
2023-06-01 22:02 ` [PULL 07/21] cutils: Fix wraparound parsing in qemu_strtoui Eric Blake
2023-06-03  8:17   ` Michael Tokarev
2023-06-05 13:32     ` Eric Blake
2023-06-01 22:02 ` [PULL 08/21] cutils: Document differences between parse_uint and qemu_strtou64 Eric Blake
2023-06-01 22:02 ` [PULL 09/21] cutils: Adjust signature of parse_uint[_full] Eric Blake
2023-06-02  6:16   ` Markus Armbruster
2023-06-02 12:22     ` Eric Blake
2023-06-01 22:02 ` [PULL 10/21] cutils: Allow NULL endptr in parse_uint() Eric Blake
2023-06-01 22:02 ` Eric Blake [this message]
2023-06-01 22:02 ` [PULL 12/21] test-cutils: Prepare for upcoming semantic change in qemu_strtosz Eric Blake
2023-06-01 22:02 ` [PULL 13/21] test-cutils: Refactor qemu_strtosz tests for less boilerplate Eric Blake
2023-06-01 22:02 ` [PULL 14/21] cutils: Allow NULL str in qemu_strtosz Eric Blake
2023-06-01 22:02 ` [PULL 15/21] numa: Check for qemu_strtosz_MiB error Eric Blake
2023-06-01 22:03 ` [PULL 16/21] test-cutils: Add more coverage to qemu_strtosz Eric Blake
2023-06-01 22:03 ` [PULL 17/21] cutils: Set value in all qemu_strtosz* error paths Eric Blake
2023-06-01 22:03 ` [PULL 18/21] cutils: Set value in all integral qemu_strto* " Eric Blake
2023-06-01 22:03 ` [PULL 19/21] cutils: Use parse_uint in qemu_strtosz for negative rejection Eric Blake
2023-06-01 22:03 ` [PULL 20/21] cutils: Improve qemu_strtod* error paths Eric Blake
2023-06-01 22:03 ` [PULL 21/21] cutils: Improve qemu_strtosz handling of fractions Eric Blake
2023-06-02  3:58 ` [PULL 00/21] NBD and miscellaneous patches for 2023-06-01 Richard Henderson
2023-06-02 12:27   ` Eric Blake
2023-06-02  6:32 ` Conclusion of yet another expensive UI folly (was: [PULL 00/21] NBD and miscellaneous patches for 2023-06-01) Markus Armbruster
2023-06-02 12:29   ` Eric Blake
2023-06-02 13:02     ` Conclusion of yet another expensive UI folly Markus Armbruster

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