Backport my_strntod() from 5.0

Change string->float conversion to delay division as long as possible.
This gives us more exact integer->float conversion for numbers of type '123.45E+02' (Bug #7740)




client/mysql.cc:
  Fix wront usage of charset (found during review of pushed code)
include/m_string.h:
  Backported my_strtod() from 5.0
mysql-test/mysql-test-run.sh:
  Run also mysql_client_test with --debug
mysql-test/r/ps_1general.result:
  Safety fix (if mysql_client_test.test fails)
mysql-test/r/type_float.result:
  More test
mysql-test/t/mysql_client_test.test:
  Comments for what to do if this test fails
mysql-test/t/ps_1general.test:
  Safety fix (if mysql_client_test.test fails)
mysql-test/t/type_float.test:
  More test to better test new strtod() function
  Test also bug #7740 (wrong comparsion between integer and float-in-integer-range)
sql/field.cc:
  Backport my_strntod() from 5.0
sql/item.cc:
  Backport my_strntod() from 5.0
sql/item.h:
  Backport my_strntod() from 5.0
sql/item_func.h:
  Backport my_strntod() from 5.0
sql/item_strfunc.cc:
  Backport my_strntod() from 5.0
sql/item_sum.cc:
  Backport my_strntod() from 5.0
sql/item_sum.h:
  Backport my_strntod() from 5.0
sql/procedure.h:
  Backport my_strntod() from 5.0
strings/ctype-simple.c:
  Backport my_strntod() from 5.0
strings/ctype-ucs2.c:
  Backport my_strntod() from 5.0
strings/strtod.c:
  Backport my_strntod() from 5.0
  Change conversion to delay division as long as possible.
  This gives us more exact integer-> float conversion for numbers of type '123.45E+02'

client/mysql.cc

@@ -2914,9 +2914,9 @@ com_status(String *buffer __attribute__((unused)),
     MYSQL_ROW cur=mysql_fetch_row(result);
     if (cur)
     {
-      tee_fprintf(stdout, "Server characterset:\t%s\n", cur[0] ? cur[2] : "");
+      tee_fprintf(stdout, "Server characterset:\t%s\n", cur[2] ? cur[2] : "");
       tee_fprintf(stdout, "Db     characterset:\t%s\n", cur[3] ? cur[3] : "");
-      tee_fprintf(stdout, "Client characterset:\t%s\n", cur[2] ? cur[0] : "");
+      tee_fprintf(stdout, "Client characterset:\t%s\n", cur[0] ? cur[0] : "");
       tee_fprintf(stdout, "Conn.  characterset:\t%s\n", cur[1] ? cur[1] : "");
     }
     mysql_free_result(result);

include/m_string.h

@@ -215,7 +215,7 @@ extern char *strstr(const char *, const char *);
 extern int is_prefix(const char *, const char *);
 
 /* Conversion routines */
-double my_strtod(const char *str, char **end);
+double my_strtod(const char *str, char **end, int *error);
 double my_atof(const char *nptr);
 
 extern char *llstr(longlong value,char *buff);

mysql-test/mysql-test-run.sh

@@ -444,6 +444,7 @@ while test $# -gt 0; do
        --debug=d:t:A,$MYSQL_TEST_DIR/var/log/mysqldump.trace"
       EXTRA_MYSQLBINLOG_OPT="$EXTRA_MYSQLBINLOG_OPT \
        --debug=d:t:A,$MYSQL_TEST_DIR/var/log/mysqlbinlog.trace"
+      EXTRA_MYSQL_CLIENT_TEST_OPT="--debug=d:t:A,$MYSQL_TEST_DIR/var/log/mysql_client_test.trace"
       ;;
     --fast)
       FAST_START=1
@@ -681,7 +682,7 @@ then
   EXTRA_SLAVE_MYSQLD_OPT="$EXTRA_SLAVE_MYSQLD_OPT --user=root"
 fi
 
-MYSQL_CLIENT_TEST="$MYSQL_CLIENT_TEST --no-defaults --testcase --user=root --socket=$MASTER_MYSOCK --port=$MYSQL_TCP_PORT --silent"
+MYSQL_CLIENT_TEST="$MYSQL_CLIENT_TEST --no-defaults --testcase --user=root --socket=$MASTER_MYSOCK --port=$MYSQL_TCP_PORT --silent $EXTRA_MYSQL_CLIENT_TEST_OPT"
 MYSQL_DUMP="$MYSQL_DUMP --no-defaults -uroot --socket=$MASTER_MYSOCK --password=$DBPASSWD $EXTRA_MYSQLDUMP_OPT"
 MYSQL_BINLOG="$MYSQL_BINLOG --no-defaults --local-load=$MYSQL_TMP_DIR $EXTRA_MYSQLBINLOG_OPT"
 MYSQL_FIX_SYSTEM_TABLES="$MYSQL_FIX_SYSTEM_TABLES --no-defaults --host=localhost --port=$MASTER_MYPORT --socket=$MASTER_MYSOCK --user=root --password=$DBPASSWD --basedir=$BASEDIR --bindir=$CLIENT_BINDIR --verbose"

mysql-test/r/ps_1general.result

@@ -1,5 +1,6 @@
 drop table if exists t5, t6, t7, t8;
 drop database if exists mysqltest ;
+drop database if exists client_test_db;
 test_sequence
 ------ basic tests ------
 drop table if exists t1, t9 ;

mysql-test/r/type_float.result

@@ -1,4 +1,4 @@
-drop table if exists t1;
+drop table if exists t1,t2;
 SELECT 10,10.0,10.,.1e+2,100.0e-1;
 10	10.0	10.	.1e+2	100.0e-1
 10	10.0	10	10	10
@@ -8,6 +8,15 @@ SELECT 6e-05, -6e-05, --6e-05, -6e-05+1.000000;
 SELECT 1e1,1.e1,1.0e1,1e+1,1.e+1,1.0e+1,1e-1,1.e-1,1.0e-1;
 1e1	1.e1	1.0e1	1e+1	1.e+1	1.0e+1	1e-1	1.e-1	1.0e-1
 10	10	10	10	10	10	0.1	0.1	0.1
+SELECT 0.001e+1,0.001e-1, -0.001e+01,-0.001e-01;
+0.001e+1	0.001e-1	-0.001e+01	-0.001e-01
+0.01	0.0001	-0.01	-0.0001
+SELECT 123.23E+02,-123.23E-02,"123.23E+02"+0.0,"-123.23E-02"+0.0;
+123.23E+02	-123.23E-02	"123.23E+02"+0.0	"-123.23E-02"+0.0
+12323	-1.2323	12323	-1.2323
+SELECT 2147483647E+02,21474836.47E+06;
+2147483647E+02	21474836.47E+06
+214748364700	21474836470000
 create table t1 (f1 float(24),f2 float(52));
 show full columns from t1;
 Field	Type	Collation	Null	Key	Default	Extra	Privileges	Comment
@@ -139,6 +148,9 @@ create table t1 (c20 char);
 insert into t1 values (5000.0);
 Warnings:
 Warning	1265	Data truncated for column 'c20' at row 1
+insert into t1 values (0.5e4);
+Warnings:
+Warning	1265	Data truncated for column 'c20' at row 1
 drop table t1;
 create table t1 (f float(54));
 ERROR 42000: Incorrect column specifier for column 'f'
@@ -203,3 +215,23 @@ c
 0.0002
 2e-05
 drop table t1;
+CREATE TABLE t1 (
+reckey int unsigned NOT NULL,
+recdesc varchar(50) NOT NULL,
+PRIMARY KEY  (reckey)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1;
+INSERT INTO t1 VALUES (108, 'Has 108 as key');
+INSERT INTO t1 VALUES (109, 'Has 109 as key');
+select * from t1 where reckey=108;
+reckey	recdesc
+108	Has 108 as key
+select * from t1 where reckey=1.08E2;
+reckey	recdesc
+108	Has 108 as key
+select * from t1 where reckey=109;
+reckey	recdesc
+109	Has 109 as key
+select * from t1 where reckey=1.09E2;
+reckey	recdesc
+109	Has 109 as key
+drop table t1;

mysql-test/t/mysql_client_test.test

@@ -1,3 +1,10 @@
 # We run with different binaries for normal and --embedded-server
+#
+# If this test fails with "command "$MYSQL_CLIENT_TEST" failed",
+# you should either run mysql_client_test separartely against a running
+# server or run mysql-test-run --debug mysql_client_test and check
+# var/log/mysql_client_test.trace
+
 --disable_result_log
+--exec echo $MYSQL_CLIENT_TEST
 --exec $MYSQL_CLIENT_TEST

mysql-test/t/ps_1general.test

@@ -11,6 +11,7 @@
 --disable_warnings
 drop table if exists t5, t6, t7, t8;
 drop database if exists mysqltest ;
+drop database if exists client_test_db;
 --enable_warnings
 
 --disable_query_log

mysql-test/t/type_float.test

@@ -3,7 +3,7 @@
 # Numeric floating point.
 
 --disable_warnings
-drop table if exists t1;
+drop table if exists t1,t2;
 --enable_warnings
 
 --replace_result e-0 e- e+0 e+
@@ -11,6 +11,9 @@ SELECT 10,10.0,10.,.1e+2,100.0e-1;
 --replace_result e-00 e-0 
 SELECT 6e-05, -6e-05, --6e-05, -6e-05+1.000000;
 SELECT 1e1,1.e1,1.0e1,1e+1,1.e+1,1.0e+1,1e-1,1.e-1,1.0e-1;
+SELECT 0.001e+1,0.001e-1, -0.001e+01,-0.001e-01;
+SELECT 123.23E+02,-123.23E-02,"123.23E+02"+0.0,"-123.23E-02"+0.0;
+SELECT 2147483647E+02,21474836.47E+06;
 
 create table t1 (f1 float(24),f2 float(52));
 show full columns from t1;
@@ -83,6 +86,7 @@ drop table t1;
 #
 create table t1 (c20 char);
 insert into t1 values (5000.0);
+insert into t1 values (0.5e4);
 drop table t1;
 
 # Errors
@@ -120,3 +124,23 @@ create table t1 (c char(6));
 insert into t1 values (2e5),(2e6),(2e-4),(2e-5);
 select * from t1;
 drop table t1;
+
+#
+# Test of comparison of integer with float-in-range (Bug #7840)
+# This is needed because some ODBC applications (like Foxpro) uses
+# floats for everything.
+#
+
+CREATE TABLE t1 (
+  reckey int unsigned NOT NULL,
+  recdesc varchar(50) NOT NULL,
+  PRIMARY KEY  (reckey)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1;
+
+INSERT INTO t1 VALUES (108, 'Has 108 as key');
+INSERT INTO t1 VALUES (109, 'Has 109 as key');
+select * from t1 where reckey=108;
+select * from t1 where reckey=1.08E2;
+select * from t1 where reckey=109;
+select * from t1 where reckey=1.09E2;
+drop table t1;

sql/field.cc

@@ -968,7 +968,9 @@ int Field_decimal::store(longlong nr)
 double Field_decimal::val_real(void)
 {
   int not_used;
-  return my_strntod(&my_charset_bin, ptr, field_length, NULL, &not_used);
+  char *end_not_used;
+  return my_strntod(&my_charset_bin, ptr, field_length, &end_not_used,
+                    &not_used);
 }
 
 longlong Field_decimal::val_int(void)
@@ -4360,8 +4362,9 @@ int Field_string::store(longlong nr)
 double Field_string::val_real(void)
 {
   int not_used;
+  char *end_not_used;
   CHARSET_INFO *cs=charset();
-  return my_strntod(cs,ptr,field_length,(char**)0,&not_used);
+  return my_strntod(cs, ptr, field_length, &end_not_used, &not_used);
 }
 
 
@@ -4577,7 +4580,9 @@ double Field_varstring::val_real(void)
   int not_used;
   uint length=uint2korr(ptr)+HA_KEY_BLOB_LENGTH;
   CHARSET_INFO *cs=charset();
-  return my_strntod(cs, ptr+HA_KEY_BLOB_LENGTH, length, (char**)0, &not_used);
+  char *end_not_used;
+  return my_strntod(cs, ptr+HA_KEY_BLOB_LENGTH, length, &end_not_used,
+                    &not_used);
 }
 
 
@@ -4955,12 +4960,13 @@ double Field_blob::val_real(void)
 {
   int not_used;
   char *blob;
+  char *end_not_used;
   memcpy_fixed(&blob,ptr+packlength,sizeof(char*));
   if (!blob)
     return 0.0;
   uint32 length=get_length(ptr);
   CHARSET_INFO *cs=charset();
-  return my_strntod(cs,blob,length,(char**)0, &not_used);
+  return my_strntod(cs,blob,length, &end_not_used, &not_used);
 }
 
 

sql/item.cc

@@ -1140,8 +1140,9 @@ double Item_param::val()
   case LONG_DATA_VALUE:
     {
       int dummy_err;
+      char *end_not_used;
       return my_strntod(str_value.charset(), (char*) str_value.ptr(),
-                        str_value.length(), (char**) 0, &dummy_err);
+                        str_value.length(), &end_not_used, &dummy_err);
     }
   case TIME_VALUE:
     /*
@@ -2585,10 +2586,12 @@ double Item_cache_str::val()
   DBUG_ASSERT(fixed == 1);
   int err;
   if (value)
+  {
+    char *end_not_used;
     return my_strntod(value->charset(), (char*) value->ptr(),
-		      value->length(), (char**) 0, &err);
+		      value->length(), &end_not_used, &err);
-  else
+  }
-    return (double)0;
+  return (double)0;
 }
 
 

sql/item.h

@@ -719,8 +719,9 @@ public:
   {
     DBUG_ASSERT(fixed == 1);
     int err;
+    char *end_not_used;
     return my_strntod(str_value.charset(), (char*) str_value.ptr(),
-		      str_value.length(), (char**) 0, &err);
+		      str_value.length(), &end_not_used, &err);
   }
   longlong val_int()
   {
@@ -1044,9 +1045,10 @@ public:
   double val()
   {
     int err;
+    char *end_not_used;
     return (null_value ? 0.0 :
 	    my_strntod(str_value.charset(), (char*) str_value.ptr(),
-		       str_value.length(),NULL,&err));
+		       str_value.length(), &end_not_used, &err));
   }
   longlong val_int()
   { 

sql/item_func.h

@@ -828,8 +828,11 @@ public:
   double val()
   {
     int err;
-    String *res;  res=val_str(&str_value);
+    String *res;
-    return res ? my_strntod(res->charset(),(char*) res->ptr(),res->length(),0,&err) : 0.0;
+    char *end_not_used;
+    res=val_str(&str_value);
+    return res ? my_strntod(res->charset(), (char*) res->ptr(), res->length(),
+                            &end_not_used, &err) : 0.0;
   }
   longlong val_int()
   {

sql/item_strfunc.cc

@@ -63,10 +63,11 @@ double Item_str_func::val()
   DBUG_ASSERT(fixed == 1);
   int err;
   char buff[64];
+  char *end_not_used;
   String *res, tmp(buff,sizeof(buff), &my_charset_bin);
   res= val_str(&tmp);
   return res ? my_strntod(res->charset(), (char*) res->ptr(),res->length(),
-			  NULL, &err) : 0.0;
+			  &end_not_used, &err) : 0.0;
 }
 
 longlong Item_str_func::val_int()

sql/item_sum.cc

@@ -471,13 +471,14 @@ double Item_sum_hybrid::val()
 {
   DBUG_ASSERT(fixed == 1);
   int err;
+  char *end_not_used;
   if (null_value)
     return 0.0;
   switch (hybrid_type) {
   case STRING_RESULT:
     String *res;  res=val_str(&str_value);
     return (res ? my_strntod(res->charset(), (char*) res->ptr(),res->length(),
-			     (char**) 0, &err) : 0.0);
+			     &end_not_used, &err) : 0.0);
   case INT_RESULT:
     if (unsigned_flag)
       return ulonglong2double(sum_int);

sql/item_sum.h

@@ -600,9 +600,11 @@ public:
   double val()
   {
     int err;
-    String *res;  res=val_str(&str_value);
+    char *end_not_used;
+    String *res;
+    res=val_str(&str_value);
     return res ? my_strntod(res->charset(),(char*) res->ptr(),res->length(),
-			    (char**) 0, &err) : 0.0;
+			    &end_not_used, &err) : 0.0;
   }
   longlong val_int()
   {

sql/procedure.h

@@ -59,7 +59,11 @@ public:
   void set(double nr) { value=nr; }
   void set(longlong nr) { value=(double) nr; }
   void set(const char *str,uint length,CHARSET_INFO *cs)
-  { int err; value=my_strntod(cs,(char*) str,length,(char**)0,&err); }
+  {
+    int err;
+    char *end_not_used;
+    value= my_strntod(cs, (char*) str, length, &end_not_used, &err);
+  }
   double val() { return value; }
   longlong val_int() { return (longlong) value; }
   String *val_str(String *s) { s->set(value,decimals,default_charset()); return s; }
@@ -99,9 +103,10 @@ public:
   double val() 
   { 
     int err;
-    CHARSET_INFO *cs=str_value.charset();
+    CHARSET_INFO *cs= str_value.charset();
+    char *end_not_used;
     return my_strntod(cs, (char*) str_value.ptr(), str_value.length(),
-		      (char**) 0, &err);
+		      &end_not_used, &err);
   }
   longlong val_int()
   { 

strings/ctype-simple.c

@@ -773,31 +773,10 @@ double my_strntod_8bit(CHARSET_INFO *cs __attribute__((unused)),
 		       char *str, uint length,
 		       char **end, int *err)
 {
-  char end_char;
-  double result;
-
-  errno= 0;					/* Safety */
-
-  /*
-    The following define is to avoid warnings from valgrind as str[length]
-    may not be defined (which is not fatal in real life)
-  */
-
-#ifdef HAVE_purify
   if (length == INT_MAX32)
-#else
+    length= 65535;                          /* Should be big enough */
-  if (length == INT_MAX32 || str[length] == 0)
+  *end= str + length;
-#endif
+  return my_strtod(str, end, err);
-    result= my_strtod(str, end);
-  else
-  {
-    end_char= str[length];
-    str[length]= 0;
-    result= my_strtod(str, end);
-    str[length]= end_char;			/* Restore end char */
-  }
-  *err= errno;
-  return result;
 }
 
 

strings/ctype-ucs2.c

@@ -946,13 +946,10 @@ double      my_strntod_ucs2(CHARSET_INFO *cs __attribute__((unused)),
       break;					/* Can't be part of double */
     *b++= (char) wc;
   }
-  *b= 0;
 
-  errno= 0;
+  *endptr= b;
-  res=my_strtod(buf, endptr);
+  res= my_strtod(buf, endptr, err);
-  *err= errno;
+  *endptr= nptr + (uint) (*endptr- buf);
-  if (endptr)
-    *endptr=(char*) (*endptr-buf+nptr);
   return res;
 }
 

strings/strtod.c

@@ -2,7 +2,7 @@
   An alternative implementation of "strtod()" that is both
   simplier, and thread-safe.
 
-  From mit-threads as bundled with MySQL 3.23
+  Original code from mit-threads as bundled with MySQL 3.23
 
   SQL:2003 specifies a number as
 
@@ -29,6 +29,8 @@
 #include "my_base.h"				/* Includes errno.h */
 #include "m_ctype.h"
 
+#define MAX_DBL_EXP	308
+#define MAX_RESULT_FOR_MAX_EXP 1.79769313486232
 static double scaler10[] = {
   1.0, 1e10, 1e20, 1e30, 1e40, 1e50, 1e60, 1e70, 1e80, 1e90
 };
@@ -37,89 +39,157 @@ static double scaler1[] = {
 };
 
 
-double my_strtod(const char *str, char **end)
+/*
+  Convert string to double (string doesn't have to be null terminated)
+
+  SYNOPSIS
+    my_strtod()
+    str		String to convert
+    end_ptr	Pointer to pointer that points to end of string
+		Will be updated to point to end of double.
+    error	Will contain error number in case of error (else 0)
+
+  RETURN
+    value of str as double
+*/
+
+double my_strtod(const char *str, char **end_ptr, int *error)
 {
   double result= 0.0;
-  int negative, ndigits;
+  uint negative= 0, ndigits, dec_digits= 0, neg_exp= 0;
-  const char *old_str;
+  int exp= 0, digits_after_dec_point= 0;
+  const char *old_str, *end= *end_ptr, *start_of_number;
+  char next_char;
   my_bool overflow=0;
 
-  while (my_isspace(&my_charset_latin1, *str))
+  *error= 0;
-    str++;
+  if (str >= end)
+    goto done;
 
+  while (my_isspace(&my_charset_latin1, *str))
+  {
+    if (++str == end)
+      goto done;
+  }
+
+  start_of_number= str;
   if ((negative= (*str == '-')) || *str=='+')
-    str++;
+  {
+    if (++str == end)
+      goto done;                                /* Could be changed to error */
+  }
+
+  /* Skip pre-zero for easier calculation of overflows */
+  while (*str == '0')
+  {
+    if (++str == end)
+      goto done;
+    start_of_number= 0;                         /* Found digit */
+  }
 
   old_str= str;
-  while (my_isdigit (&my_charset_latin1, *str))
+  while ((next_char= *str) >= '0' && next_char <= '9')
   {
-    result= result*10.0 + (*str - '0');
+    result= result*10.0 + (next_char - '0');
-    str++;
+    if (++str == end)
-  }
-  ndigits= str-old_str;
-
-  if (*str == '.')
-  {
-    double p10=10;
-    str++;
-    old_str= str;
-    while (my_isdigit (&my_charset_latin1, *str))
     {
-      result+= (*str++ - '0')/p10;
+      next_char= 0;                             /* Found end of string */
-      p10*=10;
+      break;
     }
-    ndigits+= str-old_str;
+    start_of_number= 0;                         /* Found digit */
-    if (!ndigits) str--;
   }
-  if (ndigits && (*str=='e' || *str=='E'))
+  ndigits= (uint) (str-old_str);
+
+  if (next_char == '.' && str < end-1)
+  {
+    /*
+      Continue to add numbers after decimal point to the result, as if there
+      was no decimal point. We will later (in the exponent handling) shift
+      the number down with the required number of fractions.  We do it this
+      way to be able to get maximum precision for numbers like 123.45E+02,
+      which are normal for some ODBC applications.
+    */
+    old_str= ++str;
+    while (my_isdigit(&my_charset_latin1, (next_char= *str)))
+    {
+      result= result*10.0 + (next_char - '0');
+      digits_after_dec_point++;
+      if (++str == end)
+      {
+        next_char= 0;
+        break;
+      }
+    }
+    /* If we found just '+.' or '.' then point at first character */
+    if (!(dec_digits= (uint) (str-old_str)) && start_of_number)
+      str= start_of_number;                     /* Point at '+' or '.' */
+  }
+  if ((next_char == 'e' || next_char == 'E') &&
+      dec_digits + ndigits != 0 && str < end-1)
   {
-    int exp= 0;
-    int neg= 0;
     const char *old_str= str++;
 
-    if ((neg= (*str == '-')) || *str == '+')
+    if ((neg_exp= (*str == '-')) || *str == '+')
       str++;
 
-    if (!my_isdigit (&my_charset_latin1, *str))
+    if (str == end || !my_isdigit(&my_charset_latin1, *str))
       str= old_str;
     else
     {
-      double scaler= 1.0;
+      do
-      while (my_isdigit (&my_charset_latin1, *str))
       {
-        if (exp < 9999) /* protection against exp overflow */
+        if (exp < 9999)                         /* prot. against exp overfl. */
-          exp= exp*10 + *str - '0';
+          exp= exp*10 + (*str - '0');
         str++;
-      }
+      } while (str < end && my_isdigit(&my_charset_latin1, *str));
-      if (exp >= 1000)
+    }
+  }
+  if ((exp= (neg_exp ? exp + digits_after_dec_point :
+             exp - digits_after_dec_point)))
+  {
+    double scaler;
+    if (exp < 0)
+    {
+      exp= -exp;
+      neg_exp= 1;                               /* neg_exp was 0 before */
+    }
+    if (exp + ndigits >= MAX_DBL_EXP + 1 && result)
+    {
+      /*
+        This is not 100 % as we actually will give an owerflow for
+        17E307 but not for 1.7E308 but lets cut some corners to make life
+        simpler
+      */
+      if (exp + ndigits > MAX_DBL_EXP + 1 ||
+          result >= MAX_RESULT_FOR_MAX_EXP)
       {
-	if (neg)
+        if (neg_exp)
-	  result= 0.0;
+          result= 0.0;
-	else
+        else
           overflow= 1;
         goto done;
       }
-      while (exp >= 100)
-      {
-        scaler*= 1.0e100;
-        exp-= 100;
-      }
-      scaler*= scaler10[exp/10]*scaler1[exp%10];
-      if (neg)
-        result/= scaler;
-      else
-        result*= scaler;
     }
+    scaler= 1.0;
+    while (exp >= 100)
+    {
+      scaler*= 1.0e100;
+      exp-= 100;
+    }
+    scaler*= scaler10[exp/10]*scaler1[exp%10];
+    if (neg_exp)
+      result/= scaler;
+    else
+      result*= scaler;
   }
 
 done:
-  if (end)
+  *end_ptr= (char*) str;                        /* end of number */
-    *end = (char *)str;
 
   if (overflow || isinf(result))
   {
     result= DBL_MAX;
-    errno= EOVERFLOW;
+    *error= EOVERFLOW;
   }
 
   return negative ? -result : result;
@@ -127,6 +197,7 @@ done:
 
 double my_atof(const char *nptr)
 {
-  return (my_strtod(nptr, 0));
+  int error;
+  const char *end= nptr+65535;                  /* Should be enough */
+  return (my_strtod(nptr, (char**) &end, &error));
 }
-