SQLite

Check-in [6e144735ed]
Login

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

Overview
Comment:Simplify the date/time function logic for improved rebustness and also to decrease the size of the binary.
Downloads: Tarball | ZIP archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 6e144735ed0cd3d4461ae6a4d8034264563e3165
User & Date: drh 2016-12-02 19:07:03.138
Context
2016-12-05
20:06
Work around a bug in the definition of "ino_t" on some versions of Android. (check-in: 8df492c171 user: drh tags: trunk)
2016-12-02
19:07
Simplify the date/time function logic for improved rebustness and also to decrease the size of the binary. (check-in: 6e144735ed user: drh tags: trunk)
17:08
Extend the valid range of 'unixepoch' dates from JulianDay 0 through 9999-12-31. (check-in: 768c9859b2 user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/date.c.
410
411
412
413
414
415
416
417
418
419
420

421
422
423
424
425
426
427
static void computeYMD(DateTime *p){
  int Z, A, B, C, D, E, X1;
  if( p->validYMD ) return;
  if( !p->validJD ){
    p->Y = 2000;
    p->M = 1;
    p->D = 1;
  }else if( !validJulianDay(p->iJD) ){
    datetimeError(p);
    return;
  }else{

    Z = (int)((p->iJD + 43200000)/86400000);
    A = (int)((Z - 1867216.25)/36524.25);
    A = Z + 1 + A - (A/4);
    B = A + 1524;
    C = (int)((B - 122.1)/365.25);
    D = (36525*(C&32767))/100;
    E = (int)((B-D)/30.6001);







<
<
<

>







410
411
412
413
414
415
416



417
418
419
420
421
422
423
424
425
static void computeYMD(DateTime *p){
  int Z, A, B, C, D, E, X1;
  if( p->validYMD ) return;
  if( !p->validJD ){
    p->Y = 2000;
    p->M = 1;
    p->D = 1;



  }else{
    assert( validJulianDay(p->iJD) );
    Z = (int)((p->iJD + 43200000)/86400000);
    A = (int)((Z - 1867216.25)/36524.25);
    A = Z + 1 + A - (A/4);
    B = A + 1524;
    C = (int)((B - 122.1)/365.25);
    D = (36525*(C&32767))/100;
    E = (int)((B-D)/30.6001);
593
594
595
596
597
598
599























600
601
602
603
604
605
606
  y.isError = 0;
  computeJD(&y);
  *pRc = SQLITE_OK;
  return y.iJD - x.iJD;
}
#endif /* SQLITE_OMIT_LOCALTIME */
























/*
** Process a modifier to a date-time stamp.  The modifiers are
** as follows:
**
**     NNN days
**     NNN hours
**     NNN minutes







>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>







591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
  y.isError = 0;
  computeJD(&y);
  *pRc = SQLITE_OK;
  return y.iJD - x.iJD;
}
#endif /* SQLITE_OMIT_LOCALTIME */

/*
** The following table defines various date transformations of the form
**
**            'NNN days'
**
** Where NNN is an arbitrary floating-point number and "days" can be one
** of several units of time.
*/
static const struct {
  u8 eType;           /* Transformation type code */
  u8 nName;           /* Length of th name */
  char *zName;        /* Name of the transformation */
  double rLimit;      /* Maximum NNN value for this transform */
  double rXform;      /* Constant used for this transform */
} aXformType[] = {
  { 0, 6, "second", 464269060800.0, 86400000.0/(24.0*60.0*60.0) },
  { 0, 6, "minute", 7737817680.0,   86400000.0/(24.0*60.0)      },
  { 0, 4, "hour",   128963628.0,    86400000.0/24.0             },
  { 0, 3, "day",    5373485.0,      86400000.0                  },
  { 1, 5, "month",  176546.0,       30.0*86400000.0             },
  { 2, 4, "year",   14713.0,        365.0*86400000.0            },
};

/*
** Process a modifier to a date-time stamp.  The modifiers are
** as follows:
**
**     NNN days
**     NNN hours
**     NNN minutes
617
618
619
620
621
622
623
624





625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
**     utc
**
** Return 0 on success and 1 if there is any kind of error. If the error
** is in a system call (i.e. localtime()), then an error message is written
** to context pCtx. If the error is an unrecognized modifier, no error is
** written to pCtx.
*/
static int parseModifier(sqlite3_context *pCtx, const char *zMod, DateTime *p){





  int rc = 1;
  int n;
  double r;
  char *z, zBuf[30];
  z = zBuf;
  for(n=0; n<ArraySize(zBuf)-1 && zMod[n]; n++){
    z[n] = (char)sqlite3UpperToLower[(u8)zMod[n]];
  }
  z[n] = 0;
  switch( z[0] ){
#ifndef SQLITE_OMIT_LOCALTIME
    case 'l': {
      /*    localtime
      **
      ** Assuming the current time value is UTC (a.k.a. GMT), shift it to
      ** show local time.
      */
      if( strcmp(z, "localtime")==0 ){
        computeJD(p);
        p->iJD += localtimeOffset(p, pCtx, &rc);
        clearYMD_HMS_TZ(p);
      }
      break;
    }
#endif
    case 'u': {
      /*
      **    unixepoch
      **
      ** Treat the current value of p->s as the number of
      ** seconds since 1970.  Convert to a real julian day number.
      */
      if( strcmp(z, "unixepoch")==0 && p->rawS ){
        double r = p->s*1000.0 + 210866760000000.0;
        if( r>=0.0 && r<464269060800000.0 ){
          clearYMD_HMS_TZ(p);
          p->iJD = (sqlite3_int64)r;
          p->validJD = 1;
          p->rawS = 0;
          rc = 0;
        }
      }
#ifndef SQLITE_OMIT_LOCALTIME
      else if( strcmp(z, "utc")==0 ){
        if( p->tzSet==0 ){
          sqlite3_int64 c1;
          computeJD(p);
          c1 = localtimeOffset(p, pCtx, &rc);
          if( rc==SQLITE_OK ){
            p->iJD -= c1;
            clearYMD_HMS_TZ(p);







|
>
>
>
>
>

<

<
<
<
|
<
<
<







|














|










|







638
639
640
641
642
643
644
645
646
647
648
649
650
651

652



653



654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
**     utc
**
** Return 0 on success and 1 if there is any kind of error. If the error
** is in a system call (i.e. localtime()), then an error message is written
** to context pCtx. If the error is an unrecognized modifier, no error is
** written to pCtx.
*/
static int parseModifier(
  sqlite3_context *pCtx,      /* Function context */
  const char *z,              /* The text of the modifier */
  int n,                      /* Length of zMod in bytes */
  DateTime *p                 /* The date/time value to be modified */
){
  int rc = 1;

  double r;



  switch(sqlite3UpperToLower[(u8)z[0]] ){



#ifndef SQLITE_OMIT_LOCALTIME
    case 'l': {
      /*    localtime
      **
      ** Assuming the current time value is UTC (a.k.a. GMT), shift it to
      ** show local time.
      */
      if( sqlite3_stricmp(z, "localtime")==0 ){
        computeJD(p);
        p->iJD += localtimeOffset(p, pCtx, &rc);
        clearYMD_HMS_TZ(p);
      }
      break;
    }
#endif
    case 'u': {
      /*
      **    unixepoch
      **
      ** Treat the current value of p->s as the number of
      ** seconds since 1970.  Convert to a real julian day number.
      */
      if( sqlite3_stricmp(z, "unixepoch")==0 && p->rawS ){
        double r = p->s*1000.0 + 210866760000000.0;
        if( r>=0.0 && r<464269060800000.0 ){
          clearYMD_HMS_TZ(p);
          p->iJD = (sqlite3_int64)r;
          p->validJD = 1;
          p->rawS = 0;
          rc = 0;
        }
      }
#ifndef SQLITE_OMIT_LOCALTIME
      else if( sqlite3_stricmp(z, "utc")==0 ){
        if( p->tzSet==0 ){
          sqlite3_int64 c1;
          computeJD(p);
          c1 = localtimeOffset(p, pCtx, &rc);
          if( rc==SQLITE_OK ){
            p->iJD -= c1;
            clearYMD_HMS_TZ(p);
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
      /*
      **    weekday N
      **
      ** Move the date to the same time on the next occurrence of
      ** weekday N where 0==Sunday, 1==Monday, and so forth.  If the
      ** date is already on the appropriate weekday, this is a no-op.
      */
      if( strncmp(z, "weekday ", 8)==0
               && sqlite3AtoF(&z[8], &r, sqlite3Strlen30(&z[8]), SQLITE_UTF8)
               && (n=(int)r)==r && n>=0 && r<7 ){
        sqlite3_int64 Z;
        computeYMD_HMS(p);
        p->validTZ = 0;
        p->validJD = 0;
        computeJD(p);







|







706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
      /*
      **    weekday N
      **
      ** Move the date to the same time on the next occurrence of
      ** weekday N where 0==Sunday, 1==Monday, and so forth.  If the
      ** date is already on the appropriate weekday, this is a no-op.
      */
      if( sqlite3_strnicmp(z, "weekday ", 8)==0
               && sqlite3AtoF(&z[8], &r, sqlite3Strlen30(&z[8]), SQLITE_UTF8)
               && (n=(int)r)==r && n>=0 && r<7 ){
        sqlite3_int64 Z;
        computeYMD_HMS(p);
        p->validTZ = 0;
        p->validJD = 0;
        computeJD(p);
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
    case 's': {
      /*
      **    start of TTTTT
      **
      ** Move the date backwards to the beginning of the current day,
      ** or month or year.
      */
      if( strncmp(z, "start of ", 9)!=0 ) break;
      z += 9;
      computeYMD(p);
      p->validHMS = 1;
      p->h = p->m = 0;
      p->s = 0.0;
      p->validTZ = 0;
      p->validJD = 0;
      if( strcmp(z,"month")==0 ){
        p->D = 1;
        rc = 0;
      }else if( strcmp(z,"year")==0 ){
        computeYMD(p);
        p->M = 1;
        p->D = 1;
        rc = 0;
      }else if( strcmp(z,"day")==0 ){
        rc = 0;
      }
      break;
    }
    case '+':
    case '-':
    case '0':
    case '1':
    case '2':
    case '3':
    case '4':
    case '5':
    case '6':
    case '7':
    case '8':
    case '9': {
      double rRounder;
      double rAbs;
      for(n=1; z[n] && z[n]!=':' && !sqlite3Isspace(z[n]); n++){}
      if( !sqlite3AtoF(z, &r, n, SQLITE_UTF8) ){
        rc = 1;
        break;
      }
      if( z[n]==':' ){
        /* A modifier of the form (+|-)HH:MM:SS.FFF adds (or subtracts) the







|







|


|




|

















|







729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
    case 's': {
      /*
      **    start of TTTTT
      **
      ** Move the date backwards to the beginning of the current day,
      ** or month or year.
      */
      if( sqlite3_strnicmp(z, "start of ", 9)!=0 ) break;
      z += 9;
      computeYMD(p);
      p->validHMS = 1;
      p->h = p->m = 0;
      p->s = 0.0;
      p->validTZ = 0;
      p->validJD = 0;
      if( sqlite3_stricmp(z,"month")==0 ){
        p->D = 1;
        rc = 0;
      }else if( sqlite3_stricmp(z,"year")==0 ){
        computeYMD(p);
        p->M = 1;
        p->D = 1;
        rc = 0;
      }else if( sqlite3_stricmp(z,"day")==0 ){
        rc = 0;
      }
      break;
    }
    case '+':
    case '-':
    case '0':
    case '1':
    case '2':
    case '3':
    case '4':
    case '5':
    case '6':
    case '7':
    case '8':
    case '9': {
      double rRounder;
      int i;
      for(n=1; z[n] && z[n]!=':' && !sqlite3Isspace(z[n]); n++){}
      if( !sqlite3AtoF(z, &r, n, SQLITE_UTF8) ){
        rc = 1;
        break;
      }
      if( z[n]==':' ){
        /* A modifier of the form (+|-)HH:MM:SS.FFF adds (or subtracts) the
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
        if( z[0]=='-' ) tx.iJD = -tx.iJD;
        computeJD(p);
        clearYMD_HMS_TZ(p);
        p->iJD += tx.iJD;
        rc = 0;
        break;
      }



      z += n;
      while( sqlite3Isspace(*z) ) z++;
      n = sqlite3Strlen30(z);
      if( n>10 || n<3 ) break;
      if( z[n-1]=='s' ){ z[n-1] = 0; n--; }
      computeJD(p);
      rc = 0;
      rRounder = r<0 ? -0.5 : +0.5;
      rAbs = r<0 ? -r : r;
      if( n==3 && strcmp(z,"day")==0 && rAbs<5373485.0 ){
        p->iJD += (sqlite3_int64)(r*86400000.0 + rRounder);
      }else if( n==4 && strcmp(z,"hour")==0 && rAbs<128963628.0 ){
        p->iJD += (sqlite3_int64)(r*(86400000.0/24.0) + rRounder);
      }else if( n==6 && strcmp(z,"minute")==0 && rAbs<7737817680.0 ){
        p->iJD += (sqlite3_int64)(r*(86400000.0/(24.0*60.0)) + rRounder);
      }else if( n==6 && strcmp(z,"second")==0 && rAbs<464269060800.0 ){
        p->iJD += (sqlite3_int64)(r*(86400000.0/(24.0*60.0*60.0)) + rRounder);
      }else if( n==5 && strcmp(z,"month")==0 && rAbs<176546.0 ){
        int x, y;
        computeYMD_HMS(p);
        p->M += (int)r;
        x = p->M>0 ? (p->M-1)/12 : (p->M-12)/12;
        p->Y += x;
        p->M -= x*12;
        p->validJD = 0;
        computeJD(p);
        y = (int)r;
        if( y!=r ){
          p->iJD += (sqlite3_int64)((r - y)*30.0*86400000.0 + rRounder);
        }
      }else if( n==4 && strcmp(z,"year")==0 && rAbs<14713.0 ){

        int y = (int)r;
        computeYMD_HMS(p);
        p->Y += y;
        p->validJD = 0;




        computeJD(p);
        if( y!=r ){
          p->iJD += (sqlite3_int64)((r - y)*365.0*86400000.0 + rRounder);


        }
      }else{
        rc = 1;
      }
      clearYMD_HMS_TZ(p);
      break;
    }
    default: {
      break;
    }







>
>
>




|

|

|
|
|
|
|
|
|
<
<
<
|
|
|
|
|
|
|
<
|
|
<
|
<
>
|
|
|
|
>
>
>
>
|
<
|
>
>

<
<







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
        if( z[0]=='-' ) tx.iJD = -tx.iJD;
        computeJD(p);
        clearYMD_HMS_TZ(p);
        p->iJD += tx.iJD;
        rc = 0;
        break;
      }

      /* If control reaches this point, it means the transformation is
      ** one of the forms like "+NNN days".  */
      z += n;
      while( sqlite3Isspace(*z) ) z++;
      n = sqlite3Strlen30(z);
      if( n>10 || n<3 ) break;
      if( sqlite3UpperToLower[(u8)z[n-1]]=='s' ) n--;
      computeJD(p);
      rc = 1;
      rRounder = r<0 ? -0.5 : +0.5;
      for(i=0; i<ArraySize(aXformType); i++){
        if( aXformType[i].nName==n
         && sqlite3_strnicmp(aXformType[i].zName, z, n)==0
         && r>-aXformType[i].rLimit && r<aXformType[i].rLimit
        ){
          switch( aXformType[i].eType ){
            case 1: { /* Special processing to add months */



              int x;
              computeYMD_HMS(p);
              p->M += (int)r;
              x = p->M>0 ? (p->M-1)/12 : (p->M-12)/12;
              p->Y += x;
              p->M -= x*12;
              p->validJD = 0;

              r -= (int)r;
              break;

            }

            case 2: { /* Special processing to add years */
              int y = (int)r;
              computeYMD_HMS(p);
              p->Y += y;
              p->validJD = 0;
              r -= (int)r;
              break;
            }
          }
          computeJD(p);

          p->iJD += (sqlite3_int64)(r*aXformType[i].rXform + rRounder);
          rc = 0;
          break;
        }


      }
      clearYMD_HMS_TZ(p);
      break;
    }
    default: {
      break;
    }
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
871
872
*/
static int isDate(
  sqlite3_context *context, 
  int argc, 
  sqlite3_value **argv, 
  DateTime *p
){
  int i;
  const unsigned char *z;
  int eType;
  memset(p, 0, sizeof(*p));
  if( argc==0 ){
    return setDateTimeToCurrent(context, p);
  }
  if( (eType = sqlite3_value_type(argv[0]))==SQLITE_FLOAT
                   || eType==SQLITE_INTEGER ){
    setRawDateNumber(p, sqlite3_value_double(argv[0]));
  }else{
    z = sqlite3_value_text(argv[0]);
    if( !z || parseDateOrTime(context, (char*)z, p) ){
      return 1;
    }
  }
  for(i=1; i<argc; i++){
    z = sqlite3_value_text(argv[i]);

    if( z==0 || parseModifier(context, (char*)z, p) ) return 1;
  }
  computeJD(p);
  if( p->isError || !validJulianDay(p->iJD) ) return 1;
  return 0;
}









|

















>
|







860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
*/
static int isDate(
  sqlite3_context *context, 
  int argc, 
  sqlite3_value **argv, 
  DateTime *p
){
  int i, n;
  const unsigned char *z;
  int eType;
  memset(p, 0, sizeof(*p));
  if( argc==0 ){
    return setDateTimeToCurrent(context, p);
  }
  if( (eType = sqlite3_value_type(argv[0]))==SQLITE_FLOAT
                   || eType==SQLITE_INTEGER ){
    setRawDateNumber(p, sqlite3_value_double(argv[0]));
  }else{
    z = sqlite3_value_text(argv[0]);
    if( !z || parseDateOrTime(context, (char*)z, p) ){
      return 1;
    }
  }
  for(i=1; i<argc; i++){
    z = sqlite3_value_text(argv[i]);
    n = sqlite3_value_bytes(argv[i]);
    if( z==0 || parseModifier(context, (char*)z, n, p) ) return 1;
  }
  computeJD(p);
  if( p->isError || !validJulianDay(p->iJD) ) return 1;
  return 0;
}