MDEV-16910 Add class VDec

Adding classes VDec and VDec2_lazy, according to the task description.
This patch removes around 250 duplicate code lines.

1 files changed, 79 insertions, 55 deletions

diff --git a/sql/my_decimal.h b/sql/my_decimal.h
index 22800c24338..d035641cfa6 100644
--- a/sql/my_decimal.h
+++ b/sql/my_decimal.h
@@ -39,6 +39,7 @@ C_MODE_START
 C_MODE_END
 
 class String;
+class Field;
 typedef struct st_mysql_time MYSQL_TIME;
 
 /**
@@ -63,6 +64,25 @@ inline int my_decimal_int_part(uint precision, uint decimals)
 }
 
 
+#ifndef MYSQL_CLIENT
+int decimal_operation_results(int result, const char *value, const char *type);
+#else
+inline int decimal_operation_results(int result, const char *value,
+                                     const char *type)
+{
+  return result;
+}
+#endif /*MYSQL_CLIENT*/
+
+
+inline int check_result(uint mask, int result)
+{
+  if (result & mask)
+    decimal_operation_results(result, "", "DECIMAL");
+  return result;
+}
+
+
 /**
   my_decimal class limits 'decimal_t' type to what we need in MySQL.
 
@@ -125,6 +145,12 @@ public:
   {
     init();
   }
+  my_decimal(const uchar *bin, int prec, int scale)
+  {
+    init();
+    check_result(E_DEC_FATAL_ERROR, bin2decimal(bin, this, prec, scale));
+  }
+  my_decimal(Field *field);
   ~my_decimal()
   {
     sanity_check();
@@ -141,7 +167,59 @@ public:
   bool sign() const { return decimal_t::sign; }
   void sign(bool s) { decimal_t::sign= s; }
   uint precision() const { return intg + frac; }
+  void set_zero()
+  {
+    /*
+      We need the up-cast here, since my_decimal has sign() member functions,
+      which conflicts with decimal_t::sign
+      (and decimal_make_zero is a macro, rather than a funcion).
+    */
+    decimal_make_zero(static_cast<decimal_t*>(this));
+  }
+  int cmp(const my_decimal *other) const
+  {
+    return decimal_cmp(this, other);
+  }
 
+#ifndef MYSQL_CLIENT
+  bool to_bool() const
+  {
+    return !decimal_is_zero(this);
+  }
+  double to_double() const
+  {
+    double res;
+    decimal2double(this, &res);
+    return res;
+  }
+  longlong to_longlong(bool unsigned_flag) const;
+  // Convert to string returning decimal2string() error code
+  int to_string_native(String *to, uint prec, uint dec, char filler,
+                       uint mask= E_DEC_FATAL_ERROR) const;
+  // Convert to string returning the String pointer
+  String *to_string(String *to, uint prec, uint dec, char filler) const
+  {
+    return to_string_native(to, prec, dec, filler) ? NULL : to;
+  }
+  String *to_string(String *to) const
+  {
+    return to_string(to, 0, 0, 0);
+  }
+  String *to_string_round(String *to, uint scale, my_decimal *round_buff) const
+  {
+    (void) round_to(round_buff, scale, HALF_UP); // QQ: check result?
+    return round_buff->to_string(to);
+  }
+  int round_to(my_decimal *to, uint scale, decimal_round_mode mode,
+               int mask= E_DEC_FATAL_ERROR) const
+  {
+    return check_result(mask, decimal_round(this, to, (int) scale, mode));
+  }
+  bool to_datetime_with_warn(MYSQL_TIME *to, ulonglong fuzzydate,
+                             const char *field_name);
+  int to_binary(uchar *bin, int prec, int scale,
+                uint mask= E_DEC_FATAL_ERROR) const;
+#endif
   /** Swap two my_decimal values */
   void swap(my_decimal &rhs)
   {
@@ -164,16 +242,6 @@ bool str_set_decimal(uint mask, const my_decimal *val, uint fixed_prec,
 
 extern my_decimal decimal_zero;
 
-#ifndef MYSQL_CLIENT
-int decimal_operation_results(int result, const char *value, const char *type);
-#else
-inline int decimal_operation_results(int result, const char *value,
-                                     const char *type)
-{
-  return result;
-}
-#endif /*MYSQL_CLIENT*/
-
 inline
 void max_my_decimal(my_decimal *to, int precision, int frac)
 {
@@ -187,13 +255,6 @@ inline void max_internal_decimal(my_decimal *to)
   max_my_decimal(to, DECIMAL_MAX_PRECISION, 0);
 }
 
-inline int check_result(uint mask, int result)
-{
-  if (result & mask)
-    decimal_operation_results(result, "", "DECIMAL");
-  return result;
-}
-
 inline int check_result_and_overflow(uint mask, int result, my_decimal *val)
 {
   if (check_result(mask, result) & E_DEC_OVERFLOW)
@@ -271,10 +332,6 @@ void my_decimal2decimal(const my_decimal *from, my_decimal *to)
 }
 
 
-int my_decimal2binary(uint mask, const my_decimal *d, uchar *bin, int prec,
-		      int scale);
-
-
 inline
 int binary2my_decimal(uint mask, const uchar *bin, my_decimal *d, int prec,
 		      int scale)
@@ -286,12 +343,7 @@ int binary2my_decimal(uint mask, const uchar *bin, my_decimal *d, int prec,
 inline
 int my_decimal_set_zero(my_decimal *d)
 {
-  /*
-    We need the up-cast here, since my_decimal has sign() member functions,
-    which conflicts with decimal_t::sign
-    (and decimal_make_zero is a macro, rather than a funcion).
-  */
-  decimal_make_zero(static_cast<decimal_t*>(d));
+  d->set_zero();
   return 0;
 }
 
@@ -303,40 +355,12 @@ bool my_decimal_is_zero(const my_decimal *decimal_value)
 }
 
 
-inline
-int my_decimal_round(uint mask, const my_decimal *from, int scale,
-                     bool truncate, my_decimal *to)
-{
-  return check_result(mask, decimal_round(from, to, scale,
-					  (truncate ? TRUNCATE : HALF_UP)));
-}
-
-
-inline
-int my_decimal_floor(uint mask, const my_decimal *from, my_decimal *to)
-{
-  return check_result(mask, decimal_round(from, to, 0, FLOOR));
-}
-
-
-inline
-int my_decimal_ceiling(uint mask, const my_decimal *from, my_decimal *to)
-{
-  return check_result(mask, decimal_round(from, to, 0, CEILING));
-}
-
-
 inline bool str_set_decimal(const my_decimal *val, String *str,
                             CHARSET_INFO *cs)
 {
   return str_set_decimal(E_DEC_FATAL_ERROR, val, 0, 0, 0, str, cs);
 }
 
-#ifndef MYSQL_CLIENT
-class String;
-int my_decimal2string(uint mask, const my_decimal *d, uint fixed_prec,
-		      uint fixed_dec, char filler, String *str);
-#endif
 
 bool my_decimal2seconds(const my_decimal *d, ulonglong *sec, ulong *microsec);