Fix for bug #30453: String not cast to int correctly.

Problem:

my_strntoull10rnd_8bit() handled incorrectly cases when the input
string contains a decimal point and is long enough to overrun the
'unsigned long long' type. The position of the decimal point was not
taken into account which resulted in miscalculated numbers and
truncation to appropriate SQL data type limits.

Solution:

Fix my_strntoull10rnd_8bit() to take the position of a decimal point
into account in such cases.


mysql-test/r/insert.result:
  Added a test case for bug #30453.
mysql-test/t/insert.test:
  Added a test case for bug #30453.
strings/ctype-simple.c:
  In cases when the 'unsigned long long' type is overrun by the input
  string and a decimal point has occurred, adjust the 'shift' according to
  the position of the decimal point and skip all subsequent digits.

1 files changed, 9 insertions, 5 deletions

diff --git a/strings/ctype-simple.c b/strings/ctype-simple.c
index 8b1b0d6790d..e073262cd4c 100644
--- a/strings/ctype-simple.c
+++ b/strings/ctype-simple.c
@@ -1538,14 +1538,18 @@ my_strntoull10rnd_8bit(CHARSET_INFO *cs __attribute__((unused)),
       }
       else
         addon= (*str >= '5');
-      for ( ; str < end && (ch= (unsigned char) (*str - '0')) < 10; str++)
+      if (!dot)
       {
-        if (!dot)
-          shift++;
+        for ( ; str < end && (ch= (unsigned char) (*str - '0')) < 10; shift++, str++);
+        if (str < end && *str == '.')
+        {
+          str++;
+          for ( ; str < end && (ch= (unsigned char) (*str - '0')) < 10; str++);
+        }
       }
-      if (str < end && *str == '.' && !dot)
+      else
       {
-        str++;
+        shift= dot - str;
         for ( ; str < end && (ch= (unsigned char) (*str - '0')) < 10; str++);
       }
       goto exp;