aboutsummaryrefslogtreecommitdiff
path: root/mysql/strings/int2str.c
diff options
context:
space:
mode:
Diffstat (limited to 'mysql/strings/int2str.c')
-rw-r--r--mysql/strings/int2str.c155
1 files changed, 155 insertions, 0 deletions
diff --git a/mysql/strings/int2str.c b/mysql/strings/int2str.c
new file mode 100644
index 0000000..afb89e2
--- /dev/null
+++ b/mysql/strings/int2str.c
@@ -0,0 +1,155 @@
+/* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
+
+ 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; version 2 of the License.
+
+ 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
+
+#include <my_global.h>
+#include "m_string.h"
+
+/*
+ _dig_vec arrays are public because they are used in several outer places.
+*/
+char _dig_vec_upper[] =
+ "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+char _dig_vec_lower[] =
+ "0123456789abcdefghijklmnopqrstuvwxyz";
+
+
+/*
+ Convert integer to its string representation in given scale of notation.
+
+ SYNOPSIS
+ int2str()
+ val - value to convert
+ dst - points to buffer where string representation should be stored
+ radix - radix of scale of notation
+ upcase - set to 1 if we should use upper-case digits
+
+ DESCRIPTION
+ Converts the (long) integer value to its character form and moves it to
+ the destination buffer followed by a terminating NUL.
+ If radix is -2..-36, val is taken to be SIGNED, if radix is 2..36, val is
+ taken to be UNSIGNED. That is, val is signed if and only if radix is.
+ All other radixes treated as bad and nothing will be changed in this case.
+
+ For conversion to decimal representation (radix is -10 or 10) one can use
+ optimized int10_to_str() function.
+
+ RETURN VALUE
+ Pointer to ending NUL character or NullS if radix is bad.
+*/
+
+char *
+int2str(long int val, char *dst, int radix,
+ int upcase)
+{
+ char buffer[65];
+ char *p;
+ long int new_val;
+ char *dig_vec= upcase ? _dig_vec_upper : _dig_vec_lower;
+ ulong uval= (ulong) val;
+
+ if (radix < 0)
+ {
+ if (radix < -36 || radix > -2)
+ return NullS;
+ if (val < 0)
+ {
+ *dst++ = '-';
+ /* Avoid integer overflow in (-val) for LLONG_MIN (BUG#31799). */
+ uval = (ulong)0 - uval;
+ }
+ radix = -radix;
+ }
+ else if (radix > 36 || radix < 2)
+ return NullS;
+
+ /*
+ The slightly contorted code which follows is due to the fact that
+ few machines directly support unsigned long / and %. Certainly
+ the VAX C compiler generates a subroutine call. In the interests
+ of efficiency (hollow laugh) I let this happen for the first digit
+ only; after that "val" will be in range so that signed integer
+ division will do. Sorry 'bout that. CHECK THE CODE PRODUCED BY
+ YOUR C COMPILER. The first % and / should be unsigned, the second
+ % and / signed, but C compilers tend to be extraordinarily
+ sensitive to minor details of style. This works on a VAX, that's
+ all I claim for it.
+ */
+ p = &buffer[sizeof(buffer)-1];
+ *p = '\0';
+ new_val= uval / (ulong) radix;
+ *--p = dig_vec[(uchar) (uval- (ulong) new_val*(ulong) radix)];
+ val = new_val;
+ while (val != 0)
+ {
+ ldiv_t res;
+ res=ldiv(val,radix);
+ *--p = dig_vec[res.rem];
+ val= res.quot;
+ }
+ while ((*dst++ = *p++) != 0) ;
+ return dst-1;
+}
+
+
+/*
+ Converts integer to its string representation in decimal notation.
+
+ SYNOPSIS
+ int10_to_str()
+ val - value to convert
+ dst - points to buffer where string representation should be stored
+ radix - flag that shows whenever val should be taken as signed or not
+
+ DESCRIPTION
+ This is version of int2str() function which is optimized for normal case
+ of radix 10/-10. It takes only sign of radix parameter into account and
+ not its absolute value.
+
+ RETURN VALUE
+ Pointer to ending NUL character.
+*/
+
+char *int10_to_str(long int val,char *dst,int radix)
+{
+ char buffer[65];
+ char *p;
+ long int new_val;
+ unsigned long int uval = (unsigned long int) val;
+
+ if (radix < 0) /* -10 */
+ {
+ if (val < 0)
+ {
+ *dst++ = '-';
+ /* Avoid integer overflow in (-val) for LLONG_MIN (BUG#31799). */
+ uval = (unsigned long int)0 - uval;
+ }
+ }
+
+ p = &buffer[sizeof(buffer)-1];
+ *p = '\0';
+ new_val= (long) (uval / 10);
+ *--p = '0'+ (char) (uval - (unsigned long) new_val * 10);
+ val = new_val;
+
+ while (val != 0)
+ {
+ new_val=val/10;
+ *--p = '0' + (char) (val-new_val*10);
+ val= new_val;
+ }
+ while ((*dst++ = *p++) != 0) ;
+ return dst-1;
+}