/ Check-in [3ce42e85]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Remove dead code from util.c (CVS 1396)
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1:3ce42e85a2e6c95ebc0857436d5fe9384cab8628
User & Date: drh 2004-05-18 22:03:43
Context
2004-05-18
22:17
Remove the OP_StrEq opcodes. (CVS 1397) check-in: 238442bb user: drh tags: trunk
22:03
Remove dead code from util.c (CVS 1396) check-in: 3ce42e85 user: drh tags: trunk
15:57
New varint encoding gives a maximum varint length of 9 instead of 10. (CVS 1395) check-in: 61bdb53a user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/util.c.

10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
...
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
**
*************************************************************************
** Utility functions used throughout sqlite.
**
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**
** $Id: util.c,v 1.83 2004/05/18 15:57:42 drh Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>
#include <ctype.h>

/*
** If malloc() ever fails, this global variable gets set to 1.
................................................................................
    a += strlen(&a[1]) + 2;
    b += strlen(&b[1]) + 2;
  }
  if( dir=='-' || dir=='D' ) res = -res;
  return res;
}

/*
** Some powers of 64.  These constants are needed in the
** sqlite3RealToSortable() routine below.
*/
#define _64e3  (64.0 * 64.0 * 64.0)
#define _64e4  (64.0 * 64.0 * 64.0 * 64.0)
#define _64e15 (_64e3 * _64e4 * _64e4 * _64e4)
#define _64e16 (_64e4 * _64e4 * _64e4 * _64e4)
#define _64e63 (_64e15 * _64e16 * _64e16 * _64e16)
#define _64e64 (_64e16 * _64e16 * _64e16 * _64e16)

/*
** The following procedure converts a double-precision floating point
** number into a string.  The resulting string has the property that
** two such strings comparied using strcmp() or memcmp() will give the
** same results as a numeric comparison of the original floating point
** numbers.
**
** This routine is used to generate database keys from floating point
** numbers such that the keys sort in the same order as the original
** floating point numbers even though the keys are compared using
** memcmp().
**
** The calling function should have allocated at least 14 characters
** of space for the buffer z[].
*/
void sqlite3RealToSortable(double r, char *z){
  int neg;
  int exp;
  int cnt = 0;

  /* This array maps integers between 0 and 63 into base-64 digits.
  ** The digits must be chosen such at their ASCII codes are increasing.
  ** This means we can not use the traditional base-64 digit set. */
  static const char zDigit[] = 
     "0123456789"
     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
     "abcdefghijklmnopqrstuvwxyz"
     "|~";
  if( r<0.0 ){
    neg = 1;
    r = -r;
    *z++ = '-';
  } else {
    neg = 0;
    *z++ = '0';
  }
  exp = 0;

  if( r==0.0 ){
    exp = -1024;
  }else if( r<(0.5/64.0) ){
    while( r < 0.5/_64e64 && exp > -961  ){ r *= _64e64;  exp -= 64; }
    while( r < 0.5/_64e16 && exp > -1009 ){ r *= _64e16;  exp -= 16; }
    while( r < 0.5/_64e4  && exp > -1021 ){ r *= _64e4;   exp -= 4; }
    while( r < 0.5/64.0   && exp > -1024 ){ r *= 64.0;    exp -= 1; }
  }else if( r>=0.5 ){
    while( r >= 0.5*_64e63 && exp < 960  ){ r *= 1.0/_64e64; exp += 64; }
    while( r >= 0.5*_64e15 && exp < 1008 ){ r *= 1.0/_64e16; exp += 16; }
    while( r >= 0.5*_64e3  && exp < 1020 ){ r *= 1.0/_64e4;  exp += 4; }
    while( r >= 0.5        && exp < 1023 ){ r *= 1.0/64.0;   exp += 1; }
  }
  if( neg ){
    exp = -exp;
    r = -r;
  }
  exp += 1024;
  r += 0.5;
  if( exp<0 ) return;
  if( exp>=2048 || r>=1.0 ){
    strcpy(z, "~~~~~~~~~~~~");
    return;
  }
  *z++ = zDigit[(exp>>6)&0x3f];
  *z++ = zDigit[exp & 0x3f];
  while( r>0.0 && cnt<10 ){
    int digit;
    r *= 64.0;
    digit = (int)r;
    assert( digit>=0 && digit<64 );
    *z++ = zDigit[digit & 0x3f];
    r -= digit;
    cnt++;
  }
  *z = 0;
}

#ifdef SQLITE_UTF8
/*
** X is a pointer to the first byte of a UTF-8 character.  Increment
** X so that it points to the next character.  This only works right
** if X points to a well-formed UTF-8 string.
*/
#define sqliteNextChar(X)  while( (0xc0&*++(X))==0x80 ){}







|







 







<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<







10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
...
770
771
772
773
774
775
776























































































777
778
779
780
781
782
783
**
*************************************************************************
** Utility functions used throughout sqlite.
**
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**
** $Id: util.c,v 1.84 2004/05/18 22:03:43 drh Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>
#include <ctype.h>

/*
** If malloc() ever fails, this global variable gets set to 1.
................................................................................
    a += strlen(&a[1]) + 2;
    b += strlen(&b[1]) + 2;
  }
  if( dir=='-' || dir=='D' ) res = -res;
  return res;
}
























































































#ifdef SQLITE_UTF8
/*
** X is a pointer to the first byte of a UTF-8 character.  Increment
** X so that it points to the next character.  This only works right
** if X points to a well-formed UTF-8 string.
*/
#define sqliteNextChar(X)  while( (0xc0&*++(X))==0x80 ){}