Precision Math implementation

1 files changed, 212 insertions, 0 deletions

diff --git a/sql/my_decimal.cc b/sql/my_decimal.cc
new file mode 100644
index 00000000000..eafcd2eaaf3
--- /dev/null
+++ b/sql/my_decimal.cc
@@ -0,0 +1,212 @@
+/* Copyright (C) 2004 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+#include "mysql_priv.h"
+
+#ifndef MYSQL_CLIENT
+/*
+  report result of decimal operation
+
+  SYNOPSIS
+    decimal_operation_results()
+    result  decimal library return code (E_DEC_* see include/decimal.h)
+
+  return
+    result
+*/
+int decimal_operation_results(int result)
+{
+  switch (result)
+  {
+  case E_DEC_OK:
+    break;
+//TODO: fix error messages
+  case E_DEC_TRUNCATED:
+    push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_WARN,
+			WARN_DATA_TRUNCATED, ER(WARN_DATA_TRUNCATED),
+			"", (long)-1);
+    break;
+  case E_DEC_OVERFLOW:
+    push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_ERROR,
+			ER_WARN_DATA_OUT_OF_RANGE,
+			ER(ER_WARN_DATA_OUT_OF_RANGE),
+			"", (long)-1);
+    break;
+  case E_DEC_DIV_ZERO:
+    push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_ERROR,
+			ER_DIVISION_BY_ZERO, ER(ER_DIVISION_BY_ZERO));
+    break;
+  case E_DEC_BAD_NUM:
+    push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_ERROR,
+			ER_TRUNCATED_WRONG_VALUE_FOR_FIELD,
+			ER(ER_TRUNCATED_WRONG_VALUE_FOR_FIELD),
+			"decimal", "", "", (long)-1);
+    break;
+  case E_DEC_OOM:
+    my_error(ER_OUT_OF_RESOURCES, MYF(0));
+    break;
+  default:
+    DBUG_ASSERT(0);
+  }
+  return result;
+}
+
+
+/*
+  Converting decimal to string
+
+  SYNOPSIS
+     my_decimal2string()
+
+  return
+    E_DEC_OK
+    E_DEC_TRUNCATED
+    E_DEC_OVERFLOW
+    E_DEC_OOM
+*/
+
+int my_decimal2string(uint mask, const my_decimal *d,
+                   int fixed_prec, int fixed_dec,
+                   char filler, String *str)
+{
+  int length= (fixed_prec ? (fixed_prec + 1) : my_decimal_string_length(d));
+  int result;
+  if (str->alloc(length))
+    return  check_result(mask, E_DEC_OOM);
+  char *sptr= (char *)str->ptr();
+  int res= decimal2string((decimal *)d, sptr,
+                          &length, fixed_prec, fixed_dec,
+                          filler);
+  result= check_result(mask, res);
+  str->length(length);
+  return result;
+}
+
+
+/*
+  Convert from decimal to binary representation
+
+  SYNOPSIS
+    my_decimal2binary()
+    mask        error processing mask
+    d           number for conversion
+    bin         pointer to buffer where to write result
+    prec        overall number of decimal digits
+    scale       number of decimal digits after decimal point
+
+  NOTE
+    Before conversion we round number if it need but produce truncation
+    error in this case
+
+  RETURN
+    E_DEC_OK
+    E_DEC_TRUNCATED
+    E_DEC_OVERFLOW
+*/
+
+int my_decimal2binary(uint mask, const my_decimal *d, byte *bin, int prec,
+		      int scale)
+{
+  int err1= E_DEC_OK, err2;
+  my_decimal rounded;
+  my_decimal2decimal(d, &rounded);
+  decimal_optimize_fraction(&rounded);
+  if (scale < rounded.frac)
+  {
+    err1= E_DEC_TRUNCATED;
+    /* decimal_round can return only E_DEC_TRUNCATED */
+    decimal_round(&rounded, &rounded, scale, HALF_UP);
+  }
+  err2= decimal2bin(&rounded, bin, prec, scale);
+  if (!err2)
+    err2= err1;
+  return check_result(mask, err2);
+}
+
+
+/*
+  Convert string for decimal when string can be in some multibyte charset
+
+  SYNOPSIS
+    str2my_decimal()
+    mask            error processing mask
+    from            string to process
+    length          length of given string
+    charset         charset of given string
+    decimal_value   buffer for result storing
+
+  RESULT
+    E_DEC_OK
+    E_DEC_TRUNCATED
+    E_DEC_OVERFLOW
+    E_DEC_BAD_NUM
+    E_DEC_OOM
+*/
+int str2my_decimal(uint mask, const char *from, uint length,
+                   CHARSET_INFO *charset, my_decimal *decimal_value)
+{
+  char *end;
+  int err;
+  char buff[STRING_BUFFER_USUAL_SIZE];
+  String tmp(buff, sizeof(buff), &my_charset_bin);
+  if (charset->mbminlen > 1)
+  {
+    uint dummy_errors;
+    tmp.copy(from, length, charset, &my_charset_latin1, &dummy_errors);
+    from= tmp.ptr();
+    length=  tmp.length();
+    charset= &my_charset_bin;
+  }
+  my_decimal_set_zero(decimal_value);
+  err= string2decimal((char *)from, (decimal *)decimal_value, &end);
+  if (*end && !err)
+    err= E_DEC_TRUNCATED;
+  check_result(mask, err);
+  return err;
+}
+
+
+#ifndef DBUG_OFF
+/* routines for debugging print */
+
+/* print decimal */
+void
+print_decimal(const my_decimal *dec)
+{
+  fprintf(DBUG_FILE,
+          "\nDecimal: sign: %d intg: %d frac: %d \n\
+%09d,%09d,%09d,%09d,%09d,%09d,%09d,%09d\n",
+          dec->sign(), dec->intg, dec->frac,
+          dec->buf[0], dec->buf[1], dec->buf[2], dec->buf[3],
+          dec->buf[4], dec->buf[5], dec->buf[6], dec->buf[7]);
+}
+
+
+/* print decimal with its binary representation */
+void
+print_decimal_buff(const my_decimal *dec, const byte* ptr, int length)
+{
+  print_decimal(dec);
+  fprintf(DBUG_FILE, "Record: ");
+  for(int i= 0; i < length; i++)
+  {
+    fprintf(DBUG_FILE, "%02X ", (uint)((uchar *)ptr)[i]);
+  }
+  fprintf(DBUG_FILE, "\n");
+}
+#endif
+
+
+#endif /*MYSQL_CLIENT*/