diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/date.c | 64 |
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': { |