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-rw-r--r--src/date.c64
1 files changed, 38 insertions, 26 deletions
diff --git a/src/date.c b/src/date.c
index 76e1894f8..e468925d5 100644
--- a/src/date.c
+++ b/src/date.c
@@ -1237,10 +1237,14 @@ static void dateFunc(
}
/*
-** Compute the one-based day of the year for the DateTime pDate.
-** Jan01 = 1, Jan02 = 2, ... Dec31 = 356 or 366.
+** Compute the number of days after the most recent January 1.
+**
+** In other words, compute the zero-based day number for the
+** current year:
+**
+** Jan01 = 0, Jan02 = 2, ... Dec31 = 364 or 365.
*/
-static int dayOfYear(DateTime *pDate){
+static int daysAfterJan01(DateTime *pDate){
DateTime jan01 = *pDate;
assert( jan01.validYMD );
assert( jan01.validHMS );
@@ -1249,18 +1253,33 @@ static int dayOfYear(DateTime *pDate){
jan01.M = 1;
jan01.D = 1;
computeJD(&jan01);
- return (int)((pDate->iJD-jan01.iJD+43200000)/86400000) + 1;
+ return (int)((pDate->iJD-jan01.iJD+43200000)/86400000);
}
/*
-** Return the day of the week. 1==Monday, 2=Tues, ..., 7=Sunday.
+** Return the number of days after the most recent Monday.
+**
+** In other words, return the day of the week according
+** to this code:
+**
+** 0=Monday, 1=Tuesday, 2=Wednesday, ..., 6=Sunday.
+*/
+static int daysAfterMonday(DateTime *pDate){
+ assert( pDate->validJD );
+ return (int)((pDate->iJD+43200000)/86400000) % 7;
+}
+
+/*
+** Return the number of days after the most recent Sunday.
+**
+** In other words, return the day of the week according
+** to this code:
+**
+** 0=Sunday, 1=Monday, 2=Tues, ..., 6=Saturday
*/
-static int dayOfWeek(DateTime *pDate){
- int w;
+static int daysAfterSunday(DateTime *pDate){
assert( pDate->validJD );
- w = ((pDate->iJD+129600000)/86400000) % 7;
- if( w==0 ) w = 7;
- return w;
+ return (int)((pDate->iJD+129600000)/86400000) % 7;
}
/*
@@ -1344,7 +1363,7 @@ static void strftimeFunc(
DateTime y = x;
assert( y.validJD );
/* Move y so that it is the Thursday in the same week as x */
- y.iJD += (4 - dayOfWeek(&x))*86400000;
+ y.iJD += (3 - daysAfterMonday(&x))*86400000;
y.validYMD = 0;
computeYMD(&y);
if( cf=='g' ){
@@ -1368,8 +1387,7 @@ static void strftimeFunc(
break;
}
case 'j': { /* Day of year. Jan01==1, Jan02==2, and so forth */
- int nDay = dayOfYear(&x);
- sqlite3_str_appendf(&sRes,"%03d",nDay);
+ sqlite3_str_appendf(&sRes,"%03d",daysAfterJan01(&x)+1);
break;
}
case 'J': { /* Julian day number. (Non-standard) */
@@ -1417,35 +1435,29 @@ static void strftimeFunc(
}
case 'u': /* Day of week. 1 to 7. Monday==1, Sunday==7 */
case 'w': { /* Day of week. 0 to 6. Sunday==0, Monday==1 */
- char c = (char)(((x.iJD+129600000)/86400000) % 7) + '0';
+ char c = (char)daysAfterSunday(&x) + '0';
if( c=='0' && cf=='u' ) c = '7';
sqlite3_str_appendchar(&sRes, 1, c);
break;
}
case 'U': { /* Week num. 00-53. First Sun of the year is week 01 */
- int wd; /* 0=Sunday, 1=Monday, 2=Tuesday, ... 7=Saturday */
- int nDay; /* Day of the year. 0..364 or 0..365 for leapyears */
- nDay = dayOfYear(&x);
- wd = (int)(((x.iJD+43200000)/86400000 + 1)%7);
- sqlite3_str_appendf(&sRes,"%02d",(nDay+6-wd)/7);
+ sqlite3_str_appendf(&sRes,"%02d",
+ (daysAfterJan01(&x)-daysAfterSunday(&x)+7)/7);
break;
}
case 'V': { /* Week num. 01-53. First week with a Thur is week 01 */
DateTime y = x;
/* Adjust y so that is the Thursday in the same week as x */
assert( y.validJD );
- y.iJD += (4 - dayOfWeek(&x))*86400000;
+ y.iJD += (3 - daysAfterMonday(&x))*86400000;
y.validYMD = 0;
computeYMD(&y);
- sqlite3_str_appendf(&sRes,"%02d", (dayOfYear(&y)-1)/7+1);
+ sqlite3_str_appendf(&sRes,"%02d", daysAfterJan01(&y)/7+1);
break;
}
case 'W': { /* Week num. 00-53. First Mon of the year is week 01 */
- int wd; /* 0=Monday, 1=Tuesday, ... 6=Sunday */
- int nDay; /* Day of the year. 0..364 or 0..365 for leapyears */
- nDay = dayOfYear(&x);
- wd = (int)(((x.iJD+43200000)/86400000)%7);
- sqlite3_str_appendf(&sRes,"%02d",(nDay+6-wd)/7);
+ sqlite3_str_appendf(&sRes,"%02d",
+ (daysAfterJan01(&x)-daysAfterMonday(&x)+7)/7);
break;
}
case 'Y': {