utils: Enhance testsuite for do_strtosz()

Enhance our testsuite coverage of do_strtosz() to cover some things we
know that existing users want to continue working (hex bytes), as well
as some things that accidentally work but shouldn't (hex fractions) or
accidentally fail but that users want to work (64-bit precision on
byte values).  This includes fixing a typo in the comment regarding
our parsing near 2^64.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210211204438.1184395-2-eblake@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

tests/test-cutils.c

@@ -1960,11 +1960,19 @@ static void test_qemu_strtosz_simple(void)
     g_assert_cmpint(res, ==, 0);
     g_assert(endptr == str + 1);
 
-    str = "12345";
+    /* Leading 0 gives decimal results, not octal */
+    str = "08";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, 8);
+    g_assert(endptr == str + 2);
+
+    /* Leading space is ignored */
+    str = " 12345";
     err = qemu_strtosz(str, &endptr, &res);
     g_assert_cmpint(err, ==, 0);
     g_assert_cmpint(res, ==, 12345);
-    g_assert(endptr == str + 5);
+    g_assert(endptr == str + 6);
 
     err = qemu_strtosz(str, NULL, &res);
     g_assert_cmpint(err, ==, 0);
@@ -1984,7 +1992,7 @@ static void test_qemu_strtosz_simple(void)
     g_assert_cmpint(res, ==, 0x20000000000000);
     g_assert(endptr == str + 16);
 
-    str = "9007199254740993"; /* 2^53+1 */
+    str = "9007199254740993"; /* 2^53+1 FIXME loss of precision is a bug */
     err = qemu_strtosz(str, &endptr, &res);
     g_assert_cmpint(err, ==, 0);
     g_assert_cmpint(res, ==, 0x20000000000000); /* rounded to 53 bits */
@@ -1996,14 +2004,42 @@ static void test_qemu_strtosz_simple(void)
     g_assert_cmpint(res, ==, 0xfffffffffffff800);
     g_assert(endptr == str + 20);
 
-    str = "18446744073709550591"; /* 0xfffffffffffffbff */
+    str = "18446744073709550591"; /* 0xfffffffffffffbff FIXME */
     err = qemu_strtosz(str, &endptr, &res);
     g_assert_cmpint(err, ==, 0);
     g_assert_cmpint(res, ==, 0xfffffffffffff800); /* rounded to 53 bits */
     g_assert(endptr == str + 20);
 
-    /* 0x7ffffffffffffe00..0x7fffffffffffffff get rounded to
+    /*
-     * 0x8000000000000000, thus -ERANGE; see test_qemu_strtosz_erange() */
+     * FIXME 0xfffffffffffffe00..0xffffffffffffffff get rounded to
+     * 2^64, thus -ERANGE; see test_qemu_strtosz_erange()
+     */
+}
+
+static void test_qemu_strtosz_hex(void)
+{
+    const char *str;
+    const char *endptr;
+    int err;
+    uint64_t res = 0xbaadf00d;
+
+    str = "0x0";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, 0);
+    g_assert(endptr == str + 3);
+
+    str = "0xab";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, 171);
+    g_assert(endptr == str + 4);
+
+    str = "0xae";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, 174);
+    g_assert(endptr == str + 4);
 }
 
 static void test_qemu_strtosz_units(void)
@@ -2064,14 +2100,36 @@ static void test_qemu_strtosz_units(void)
 
 static void test_qemu_strtosz_float(void)
 {
-    const char *str = "12.345M";
+    const char *str;
     int err;
     const char *endptr;
     uint64_t res = 0xbaadf00d;
 
+    str = "0.5E";
     err = qemu_strtosz(str, &endptr, &res);
     g_assert_cmpint(err, ==, 0);
-    g_assert_cmpint(res, ==, 12.345 * MiB);
+    g_assert_cmpint(res, ==, EiB / 2);
+    g_assert(endptr == str + 4);
+
+    /* For convenience, a fraction of 0 is tolerated even on bytes */
+    str = "1.0B";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, 1);
+    g_assert(endptr == str + 4);
+
+    /* An empty fraction is tolerated */
+    str = "1.k";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, 1024);
+    g_assert(endptr == str + 3);
+
+    /* For convenience, we permit values that are not byte-exact */
+    str = "12.345M";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, (uint64_t) (12.345 * MiB));
     g_assert(endptr == str + 7);
 }
 
@@ -2106,6 +2164,47 @@ static void test_qemu_strtosz_invalid(void)
     err = qemu_strtosz(str, &endptr, &res);
     g_assert_cmpint(err, ==, -EINVAL);
     g_assert(endptr == str);
+
+    /* Fractional values require scale larger than bytes */
+    /* FIXME endptr shouldn't move on -EINVAL */
+    str = "1.1B";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert(endptr == str + 4);
+
+    /* FIXME endptr shouldn't move on -EINVAL */
+    str = "1.1";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+    g_assert(endptr == str + 3);
+
+    /* FIXME we should reject floating point exponents */
+    str = "1.5e1k";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, 15360);
+    g_assert(endptr == str + 6);
+
+    /* FIXME we should reject floating point exponents */
+    str = "1.5E+0k";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, 1536);
+    g_assert(endptr == str + 7);
+
+    /* FIXME we should reject hex fractions */
+    str = "0x1.8k";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, 1536);
+    g_assert(endptr == str + 6);
+
+    /* FIXME we reject all other attempts at negative, why not -0 */
+    str = "-0";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, 0);
+    g_assert(endptr == str + 2);
 }
 
 static void test_qemu_strtosz_trailing(void)
@@ -2131,6 +2230,30 @@ static void test_qemu_strtosz_trailing(void)
 
     err = qemu_strtosz(str, NULL, &res);
     g_assert_cmpint(err, ==, -EINVAL);
+
+    str = "0x";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(res, ==, 0);
+    g_assert(endptr == str + 1);
+
+    err = qemu_strtosz(str, NULL, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+
+    str = "0.NaN";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert(endptr == str + 2);
+
+    err = qemu_strtosz(str, NULL, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
+
+    str = "123-45";
+    err = qemu_strtosz(str, &endptr, &res);
+    g_assert_cmpint(res, ==, 123);
+    g_assert(endptr == str + 3);
+
+    err = qemu_strtosz(str, NULL, &res);
+    g_assert_cmpint(err, ==, -EINVAL);
 }
 
 static void test_qemu_strtosz_erange(void)
@@ -2145,12 +2268,12 @@ static void test_qemu_strtosz_erange(void)
     g_assert_cmpint(err, ==, -ERANGE);
     g_assert(endptr == str + 2);
 
-    str = "18446744073709550592"; /* 0xfffffffffffffc00 */
+    str = "18446744073709550592"; /* 0xfffffffffffffc00 FIXME accept this */
     err = qemu_strtosz(str, &endptr, &res);
     g_assert_cmpint(err, ==, -ERANGE);
     g_assert(endptr == str + 20);
 
-    str = "18446744073709551615"; /* 2^64-1 */
+    str = "18446744073709551615"; /* 2^64-1 FIXME accept this */
     err = qemu_strtosz(str, &endptr, &res);
     g_assert_cmpint(err, ==, -ERANGE);
     g_assert(endptr == str + 20);
@@ -2168,15 +2291,22 @@ static void test_qemu_strtosz_erange(void)
 
 static void test_qemu_strtosz_metric(void)
 {
-    const char *str = "12345k";
+    const char *str;
     int err;
     const char *endptr;
     uint64_t res = 0xbaadf00d;
 
+    str = "12345k";
     err = qemu_strtosz_metric(str, &endptr, &res);
     g_assert_cmpint(err, ==, 0);
     g_assert_cmpint(res, ==, 12345000);
     g_assert(endptr == str + 6);
+
+    str = "12.345M";
+    err = qemu_strtosz_metric(str, &endptr, &res);
+    g_assert_cmpint(err, ==, 0);
+    g_assert_cmpint(res, ==, 12345000);
+    g_assert(endptr == str + 7);
 }
 
 int main(int argc, char **argv)
@@ -2443,6 +2573,8 @@ int main(int argc, char **argv)
 
     g_test_add_func("/cutils/strtosz/simple",
                     test_qemu_strtosz_simple);
+    g_test_add_func("/cutils/strtosz/hex",
+                    test_qemu_strtosz_hex);
     g_test_add_func("/cutils/strtosz/units",
                     test_qemu_strtosz_units);
     g_test_add_func("/cutils/strtosz/float",