blob: e271210679c989cc03e82b3b3d3df89cd9190c9e [file] [log] [blame]
/*
** 2003 October 31
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the C functions that implement date and time
** functions for SQLite.
**
** There is only one exported symbol in this file - the function
** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
** All other code has file scope.
**
** SQLite processes all times and dates as julian day numbers. The
** dates and times are stored as the number of days since noon
** in Greenwich on November 24, 4714 B.C. according to the Gregorian
** calendar system.
**
** 1970-01-01 00:00:00 is JD 2440587.5
** 2000-01-01 00:00:00 is JD 2451544.5
**
** This implementation requires years to be expressed as a 4-digit number
** which means that only dates between 0000-01-01 and 9999-12-31 can
** be represented, even though julian day numbers allow a much wider
** range of dates.
**
** The Gregorian calendar system is used for all dates and times,
** even those that predate the Gregorian calendar. Historians usually
** use the julian calendar for dates prior to 1582-10-15 and for some
** dates afterwards, depending on locale. Beware of this difference.
**
** The conversion algorithms are implemented based on descriptions
** in the following text:
**
** Jean Meeus
** Astronomical Algorithms, 2nd Edition, 1998
** ISBN 0-943396-61-1
** Willmann-Bell, Inc
** Richmond, Virginia (USA)
*/
#include "sqliteInt.h"
#include <stdlib.h>
#include <assert.h>
#include <time.h>
#ifndef SQLITE_OMIT_DATETIME_FUNCS
/*
** The MSVC CRT on Windows CE may not have a localtime() function.
** So declare a substitute. The substitute function itself is
** defined in "os_win.c".
*/
#if !defined(SQLITE_OMIT_LOCALTIME) && defined(_WIN32_WCE) && \
(!defined(SQLITE_MSVC_LOCALTIME_API) || !SQLITE_MSVC_LOCALTIME_API)
struct tm *__cdecl localtime(const time_t *);
#endif
/*
** A structure for holding a single date and time.
*/
typedef struct DateTime DateTime;
struct DateTime {
sqlite3_int64 iJD; /* The julian day number times 86400000 */
int Y, M, D; /* Year, month, and day */
int h, m; /* Hour and minutes */
int tz; /* Timezone offset in minutes */
double s; /* Seconds */
char validJD; /* True (1) if iJD is valid */
char rawS; /* Raw numeric value stored in s */
char validYMD; /* True (1) if Y,M,D are valid */
char validHMS; /* True (1) if h,m,s are valid */
char validTZ; /* True (1) if tz is valid */
char tzSet; /* Timezone was set explicitly */
char isError; /* An overflow has occurred */
};
/*
** Convert zDate into one or more integers according to the conversion
** specifier zFormat.
**
** zFormat[] contains 4 characters for each integer converted, except for
** the last integer which is specified by three characters. The meaning
** of a four-character format specifiers ABCD is:
**
** A: number of digits to convert. Always "2" or "4".
** B: minimum value. Always "0" or "1".
** C: maximum value, decoded as:
** a: 12
** b: 14
** c: 24
** d: 31
** e: 59
** f: 9999
** D: the separator character, or \000 to indicate this is the
** last number to convert.
**
** Example: To translate an ISO-8601 date YYYY-MM-DD, the format would
** be "40f-21a-20c". The "40f-" indicates the 4-digit year followed by "-".
** The "21a-" indicates the 2-digit month followed by "-". The "20c" indicates
** the 2-digit day which is the last integer in the set.
**
** The function returns the number of successful conversions.
*/
static int getDigits(const char *zDate, const char *zFormat, ...){
/* The aMx[] array translates the 3rd character of each format
** spec into a max size: a b c d e f */
static const u16 aMx[] = { 12, 14, 24, 31, 59, 9999 };
va_list ap;
int cnt = 0;
char nextC;
va_start(ap, zFormat);
do{
char N = zFormat[0] - '0';
char min = zFormat[1] - '0';
int val = 0;
u16 max;
assert( zFormat[2]>='a' && zFormat[2]<='f' );
max = aMx[zFormat[2] - 'a'];
nextC = zFormat[3];
val = 0;
while( N-- ){
if( !sqlite3Isdigit(*zDate) ){
goto end_getDigits;
}
val = val*10 + *zDate - '0';
zDate++;
}
if( val<(int)min || val>(int)max || (nextC!=0 && nextC!=*zDate) ){
goto end_getDigits;
}
*va_arg(ap,int*) = val;
zDate++;
cnt++;
zFormat += 4;
}while( nextC );
end_getDigits:
va_end(ap);
return cnt;
}
/*
** Parse a timezone extension on the end of a date-time.
** The extension is of the form:
**
** (+/-)HH:MM
**
** Or the "zulu" notation:
**
** Z
**
** If the parse is successful, write the number of minutes
** of change in p->tz and return 0. If a parser error occurs,
** return non-zero.
**
** A missing specifier is not considered an error.
*/
static int parseTimezone(const char *zDate, DateTime *p){
int sgn = 0;
int nHr, nMn;
int c;
while( sqlite3Isspace(*zDate) ){ zDate++; }
p->tz = 0;
c = *zDate;
if( c=='-' ){
sgn = -1;
}else if( c=='+' ){
sgn = +1;
}else if( c=='Z' || c=='z' ){
zDate++;
goto zulu_time;
}else{
return c!=0;
}
zDate++;
if( getDigits(zDate, "20b:20e", &nHr, &nMn)!=2 ){
return 1;
}
zDate += 5;
p->tz = sgn*(nMn + nHr*60);
zulu_time:
while( sqlite3Isspace(*zDate) ){ zDate++; }
p->tzSet = 1;
return *zDate!=0;
}
/*
** Parse times of the form HH:MM or HH:MM:SS or HH:MM:SS.FFFF.
** The HH, MM, and SS must each be exactly 2 digits. The
** fractional seconds FFFF can be one or more digits.
**
** Return 1 if there is a parsing error and 0 on success.
*/
static int parseHhMmSs(const char *zDate, DateTime *p){
int h, m, s;
double ms = 0.0;
if( getDigits(zDate, "20c:20e", &h, &m)!=2 ){
return 1;
}
zDate += 5;
if( *zDate==':' ){
zDate++;
if( getDigits(zDate, "20e", &s)!=1 ){
return 1;
}
zDate += 2;
if( *zDate=='.' && sqlite3Isdigit(zDate[1]) ){
double rScale = 1.0;
zDate++;
while( sqlite3Isdigit(*zDate) ){
ms = ms*10.0 + *zDate - '0';
rScale *= 10.0;
zDate++;
}
ms /= rScale;
}
}else{
s = 0;
}
p->validJD = 0;
p->rawS = 0;
p->validHMS = 1;
p->h = h;
p->m = m;
p->s = s + ms;
if( parseTimezone(zDate, p) ) return 1;
p->validTZ = (p->tz!=0)?1:0;
return 0;
}
/*
** Put the DateTime object into its error state.
*/
static void datetimeError(DateTime *p){
memset(p, 0, sizeof(*p));
p->isError = 1;
}
/*
** Convert from YYYY-MM-DD HH:MM:SS to julian day. We always assume
** that the YYYY-MM-DD is according to the Gregorian calendar.
**
** Reference: Meeus page 61
*/
static void computeJD(DateTime *p){
int Y, M, D, A, B, X1, X2;
if( p->validJD ) return;
if( p->validYMD ){
Y = p->Y;
M = p->M;
D = p->D;
}else{
Y = 2000; /* If no YMD specified, assume 2000-Jan-01 */
M = 1;
D = 1;
}
if( Y<-4713 || Y>9999 || p->rawS ){
datetimeError(p);
return;
}
if( M<=2 ){
Y--;
M += 12;
}
A = Y/100;
B = 2 - A + (A/4);
X1 = 36525*(Y+4716)/100;
X2 = 306001*(M+1)/10000;
p->iJD = (sqlite3_int64)((X1 + X2 + D + B - 1524.5 ) * 86400000);
p->validJD = 1;
if( p->validHMS ){
p->iJD += p->h*3600000 + p->m*60000 + (sqlite3_int64)(p->s*1000);
if( p->validTZ ){
p->iJD -= p->tz*60000;
p->validYMD = 0;
p->validHMS = 0;
p->validTZ = 0;
}
}
}
/*
** Parse dates of the form
**
** YYYY-MM-DD HH:MM:SS.FFF
** YYYY-MM-DD HH:MM:SS
** YYYY-MM-DD HH:MM
** YYYY-MM-DD
**
** Write the result into the DateTime structure and return 0
** on success and 1 if the input string is not a well-formed
** date.
*/
static int parseYyyyMmDd(const char *zDate, DateTime *p){
int Y, M, D, neg;
if( zDate[0]=='-' ){
zDate++;
neg = 1;
}else{
neg = 0;
}
if( getDigits(zDate, "40f-21a-21d", &Y, &M, &D)!=3 ){
return 1;
}
zDate += 10;
while( sqlite3Isspace(*zDate) || 'T'==*(u8*)zDate ){ zDate++; }
if( parseHhMmSs(zDate, p)==0 ){
/* We got the time */
}else if( *zDate==0 ){
p->validHMS = 0;
}else{
return 1;
}
p->validJD = 0;
p->validYMD = 1;
p->Y = neg ? -Y : Y;
p->M = M;
p->D = D;
if( p->validTZ ){
computeJD(p);
}
return 0;
}
/*
** Set the time to the current time reported by the VFS.
**
** Return the number of errors.
*/
static int setDateTimeToCurrent(sqlite3_context *context, DateTime *p){
p->iJD = sqlite3StmtCurrentTime(context);
if( p->iJD>0 ){
p->validJD = 1;
return 0;
}else{
return 1;
}
}
/*
** Input "r" is a numeric quantity which might be a julian day number,
** or the number of seconds since 1970. If the value if r is within
** range of a julian day number, install it as such and set validJD.
** If the value is a valid unix timestamp, put it in p->s and set p->rawS.
*/
static void setRawDateNumber(DateTime *p, double r){
p->s = r;
p->rawS = 1;
if( r>=0.0 && r<5373484.5 ){
p->iJD = (sqlite3_int64)(r*86400000.0 + 0.5);
p->validJD = 1;
}
}
/*
** Attempt to parse the given string into a julian day number. Return
** the number of errors.
**
** The following are acceptable forms for the input string:
**
** YYYY-MM-DD HH:MM:SS.FFF +/-HH:MM
** DDDD.DD
** now
**
** In the first form, the +/-HH:MM is always optional. The fractional
** seconds extension (the ".FFF") is optional. The seconds portion
** (":SS.FFF") is option. The year and date can be omitted as long
** as there is a time string. The time string can be omitted as long
** as there is a year and date.
*/
static int parseDateOrTime(
sqlite3_context *context,
const char *zDate,
DateTime *p
){
double r;
if( parseYyyyMmDd(zDate,p)==0 ){
return 0;
}else if( parseHhMmSs(zDate, p)==0 ){
return 0;
}else if( sqlite3StrICmp(zDate,"now")==0 && sqlite3NotPureFunc(context) ){
return setDateTimeToCurrent(context, p);
}else if( sqlite3AtoF(zDate, &r, sqlite3Strlen30(zDate), SQLITE_UTF8)>0 ){
setRawDateNumber(p, r);
return 0;
}
return 1;
}
/* The julian day number for 9999-12-31 23:59:59.999 is 5373484.4999999.
** Multiplying this by 86400000 gives 464269060799999 as the maximum value
** for DateTime.iJD.
**
** But some older compilers (ex: gcc 4.2.1 on older Macs) cannot deal with
** such a large integer literal, so we have to encode it.
*/
#define INT_464269060799999 ((((i64)0x1a640)<<32)|0x1072fdff)
/*
** Return TRUE if the given julian day number is within range.
**
** The input is the JulianDay times 86400000.
*/
static int validJulianDay(sqlite3_int64 iJD){
return iJD>=0 && iJD<=INT_464269060799999;
}
/*
** Compute the Year, Month, and Day from the julian day number.
*/
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);
X1 = (int)(30.6001*E);
p->D = B - D - X1;
p->M = E<14 ? E-1 : E-13;
p->Y = p->M>2 ? C - 4716 : C - 4715;
}
p->validYMD = 1;
}
/*
** Compute the Hour, Minute, and Seconds from the julian day number.
*/
static void computeHMS(DateTime *p){
int s;
if( p->validHMS ) return;
computeJD(p);
s = (int)((p->iJD + 43200000) % 86400000);
p->s = s/1000.0;
s = (int)p->s;
p->s -= s;
p->h = s/3600;
s -= p->h*3600;
p->m = s/60;
p->s += s - p->m*60;
p->rawS = 0;
p->validHMS = 1;
}
/*
** Compute both YMD and HMS
*/
static void computeYMD_HMS(DateTime *p){
computeYMD(p);
computeHMS(p);
}
/*
** Clear the YMD and HMS and the TZ
*/
static void clearYMD_HMS_TZ(DateTime *p){
p->validYMD = 0;
p->validHMS = 0;
p->validTZ = 0;
}
#ifndef SQLITE_OMIT_LOCALTIME
/*
** On recent Windows platforms, the localtime_s() function is available
** as part of the "Secure CRT". It is essentially equivalent to
** localtime_r() available under most POSIX platforms, except that the
** order of the parameters is reversed.
**
** See http://msdn.microsoft.com/en-us/library/a442x3ye(VS.80).aspx.
**
** If the user has not indicated to use localtime_r() or localtime_s()
** already, check for an MSVC build environment that provides
** localtime_s().
*/
#if !HAVE_LOCALTIME_R && !HAVE_LOCALTIME_S \
&& defined(_MSC_VER) && defined(_CRT_INSECURE_DEPRECATE)
#undef HAVE_LOCALTIME_S
#define HAVE_LOCALTIME_S 1
#endif
/*
** The following routine implements the rough equivalent of localtime_r()
** using whatever operating-system specific localtime facility that
** is available. This routine returns 0 on success and
** non-zero on any kind of error.
**
** If the sqlite3GlobalConfig.bLocaltimeFault variable is true then this
** routine will always fail.
**
** EVIDENCE-OF: R-62172-00036 In this implementation, the standard C
** library function localtime_r() is used to assist in the calculation of
** local time.
*/
static int osLocaltime(time_t *t, struct tm *pTm){
int rc;
#if !HAVE_LOCALTIME_R && !HAVE_LOCALTIME_S
struct tm *pX;
#if SQLITE_THREADSAFE>0
sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
#endif
sqlite3_mutex_enter(mutex);
pX = localtime(t);
#ifndef SQLITE_UNTESTABLE
if( sqlite3GlobalConfig.bLocaltimeFault ) pX = 0;
#endif
if( pX ) *pTm = *pX;
sqlite3_mutex_leave(mutex);
rc = pX==0;
#else
#ifndef SQLITE_UNTESTABLE
if( sqlite3GlobalConfig.bLocaltimeFault ) return 1;
#endif
#if HAVE_LOCALTIME_R
rc = localtime_r(t, pTm)==0;
#else
rc = localtime_s(pTm, t);
#endif /* HAVE_LOCALTIME_R */
#endif /* HAVE_LOCALTIME_R || HAVE_LOCALTIME_S */
return rc;
}
#endif /* SQLITE_OMIT_LOCALTIME */
#ifndef SQLITE_OMIT_LOCALTIME
/*
** Compute the difference (in milliseconds) between localtime and UTC
** (a.k.a. GMT) for the time value p where p is in UTC. If no error occurs,
** return this value and set *pRc to SQLITE_OK.
**
** Or, if an error does occur, set *pRc to SQLITE_ERROR. The returned value
** is undefined in this case.
*/
static sqlite3_int64 localtimeOffset(
DateTime *p, /* Date at which to calculate offset */
sqlite3_context *pCtx, /* Write error here if one occurs */
int *pRc /* OUT: Error code. SQLITE_OK or ERROR */
){
DateTime x, y;
time_t t;
struct tm sLocal;
/* Initialize the contents of sLocal to avoid a compiler warning. */
memset(&sLocal, 0, sizeof(sLocal));
x = *p;
computeYMD_HMS(&x);
if( x.Y<1971 || x.Y>=2038 ){
/* EVIDENCE-OF: R-55269-29598 The localtime_r() C function normally only
** works for years between 1970 and 2037. For dates outside this range,
** SQLite attempts to map the year into an equivalent year within this
** range, do the calculation, then map the year back.
*/
x.Y = 2000;
x.M = 1;
x.D = 1;
x.h = 0;
x.m = 0;
x.s = 0.0;
} else {
int s = (int)(x.s + 0.5);
x.s = s;
}
x.tz = 0;
x.validJD = 0;
computeJD(&x);
t = (time_t)(x.iJD/1000 - 21086676*(i64)10000);
if( osLocaltime(&t, &sLocal) ){
sqlite3_result_error(pCtx, "local time unavailable", -1);
*pRc = SQLITE_ERROR;
return 0;
}
y.Y = sLocal.tm_year + 1900;
y.M = sLocal.tm_mon + 1;
y.D = sLocal.tm_mday;
y.h = sLocal.tm_hour;
y.m = sLocal.tm_min;
y.s = sLocal.tm_sec;
y.validYMD = 1;
y.validHMS = 1;
y.validJD = 0;
y.rawS = 0;
y.validTZ = 0;
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
** NNN.NNNN seconds
** NNN months
** NNN years
** start of month
** start of year
** start of week
** start of day
** weekday N
** unixepoch
** localtime
** 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 && sqlite3NotPureFunc(pCtx) ){
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 ){
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 && sqlite3NotPureFunc(pCtx) ){
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);
p->iJD += c1 - localtimeOffset(p, pCtx, &rc);
}
p->tzSet = 1;
}else{
rc = SQLITE_OK;
}
}
#endif
break;
}
case 'w': {
/*
** 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)>0
&& (n=(int)r)==r && n>=0 && r<7 ){
sqlite3_int64 Z;
computeYMD_HMS(p);
p->validTZ = 0;
p->validJD = 0;
computeJD(p);
Z = ((p->iJD + 129600000)/86400000) % 7;
if( Z>n ) Z -= 7;
p->iJD += (n - Z)*86400000;
clearYMD_HMS_TZ(p);
rc = 0;
}
break;
}
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;
if( !p->validJD && !p->validYMD && !p->validHMS ) break;
z += 9;
computeYMD(p);
p->validHMS = 1;
p->h = p->m = 0;
p->s = 0.0;
p->rawS = 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 ){
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)<=0 ){
rc = 1;
break;
}
if( z[n]==':' ){
/* A modifier of the form (+|-)HH:MM:SS.FFF adds (or subtracts) the
** specified number of hours, minutes, seconds, and fractional seconds
** to the time. The ".FFF" may be omitted. The ":SS.FFF" may be
** omitted.
*/
const char *z2 = z;
DateTime tx;
sqlite3_int64 day;
if( !sqlite3Isdigit(*z2) ) z2++;
memset(&tx, 0, sizeof(tx));
if( parseHhMmSs(z2, &tx) ) break;
computeJD(&tx);
tx.iJD -= 43200000;
day = tx.iJD/86400000;
tx.iJD -= day*86400000;
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;
}
}
return rc;
}
/*
** Process time function arguments. argv[0] is a date-time stamp.
** argv[1] and following are modifiers. Parse them all and write
** the resulting time into the DateTime structure p. Return 0
** on success and 1 if there are any errors.
**
** If there are zero parameters (if even argv[0] is undefined)
** then assume a default value of "now" for argv[0].
*/
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;
}
/*
** The following routines implement the various date and time functions
** of SQLite.
*/
/*
** julianday( TIMESTRING, MOD, MOD, ...)
**
** Return the julian day number of the date specified in the arguments
*/
static void juliandayFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
DateTime x;
if( isDate(context, argc, argv, &x)==0 ){
computeJD(&x);
sqlite3_result_double(context, x.iJD/86400000.0);
}
}
/*
** datetime( TIMESTRING, MOD, MOD, ...)
**
** Return YYYY-MM-DD HH:MM:SS
*/
static void datetimeFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
DateTime x;
if( isDate(context, argc, argv, &x)==0 ){
char zBuf[100];
computeYMD_HMS(&x);
sqlite3_snprintf(sizeof(zBuf), zBuf, "%04d-%02d-%02d %02d:%02d:%02d",
x.Y, x.M, x.D, x.h, x.m, (int)(x.s));
sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
}
}
/*
** time( TIMESTRING, MOD, MOD, ...)
**
** Return HH:MM:SS
*/
static void timeFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
DateTime x;
if( isDate(context, argc, argv, &x)==0 ){
char zBuf[100];
computeHMS(&x);
sqlite3_snprintf(sizeof(zBuf), zBuf, "%02d:%02d:%02d", x.h, x.m, (int)x.s);
sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
}
}
/*
** date( TIMESTRING, MOD, MOD, ...)
**
** Return YYYY-MM-DD
*/
static void dateFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
DateTime x;
if( isDate(context, argc, argv, &x)==0 ){
char zBuf[100];
computeYMD(&x);
sqlite3_snprintf(sizeof(zBuf), zBuf, "%04d-%02d-%02d", x.Y, x.M, x.D);
sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
}
}
/*
** strftime( FORMAT, TIMESTRING, MOD, MOD, ...)
**
** Return a string described by FORMAT. Conversions as follows:
**
** %d day of month
** %f ** fractional seconds SS.SSS
** %H hour 00-24
** %j day of year 000-366
** %J ** julian day number
** %m month 01-12
** %M minute 00-59
** %s seconds since 1970-01-01
** %S seconds 00-59
** %w day of week 0-6 sunday==0
** %W week of year 00-53
** %Y year 0000-9999
** %% %
*/
static void strftimeFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
DateTime x;
u64 n;
size_t i,j;
char *z;
sqlite3 *db;
const char *zFmt;
char zBuf[100];
if( argc==0 ) return;
zFmt = (const char*)sqlite3_value_text(argv[0]);
if( zFmt==0 || isDate(context, argc-1, argv+1, &x) ) return;
db = sqlite3_context_db_handle(context);
for(i=0, n=1; zFmt[i]; i++, n++){
if( zFmt[i]=='%' ){
switch( zFmt[i+1] ){
case 'd':
case 'H':
case 'm':
case 'M':
case 'S':
case 'W':
n++;
/* fall thru */
case 'w':
case '%':
break;
case 'f':
n += 8;
break;
case 'j':
n += 3;
break;
case 'Y':
n += 8;
break;
case 's':
case 'J':
n += 50;
break;
default:
return; /* ERROR. return a NULL */
}
i++;
}
}
testcase( n==sizeof(zBuf)-1 );
testcase( n==sizeof(zBuf) );
testcase( n==(u64)db->aLimit[SQLITE_LIMIT_LENGTH]+1 );
testcase( n==(u64)db->aLimit[SQLITE_LIMIT_LENGTH] );
if( n<sizeof(zBuf) ){
z = zBuf;
}else if( n>(u64)db->aLimit[SQLITE_LIMIT_LENGTH] ){
sqlite3_result_error_toobig(context);
return;
}else{
z = sqlite3DbMallocRawNN(db, (int)n);
if( z==0 ){
sqlite3_result_error_nomem(context);
return;
}
}
computeJD(&x);
computeYMD_HMS(&x);
for(i=j=0; zFmt[i]; i++){
if( zFmt[i]!='%' ){
z[j++] = zFmt[i];
}else{
i++;
switch( zFmt[i] ){
case 'd': sqlite3_snprintf(3, &z[j],"%02d",x.D); j+=2; break;
case 'f': {
double s = x.s;
if( s>59.999 ) s = 59.999;
sqlite3_snprintf(7, &z[j],"%06.3f", s);
j += sqlite3Strlen30(&z[j]);
break;
}
case 'H': sqlite3_snprintf(3, &z[j],"%02d",x.h); j+=2; break;
case 'W': /* Fall thru */
case 'j': {
int nDay; /* Number of days since 1st day of year */
DateTime y = x;
y.validJD = 0;
y.M = 1;
y.D = 1;
computeJD(&y);
nDay = (int)((x.iJD-y.iJD+43200000)/86400000);
if( zFmt[i]=='W' ){
int wd; /* 0=Monday, 1=Tuesday, ... 6=Sunday */
wd = (int)(((x.iJD+43200000)/86400000)%7);
sqlite3_snprintf(3, &z[j],"%02d",(nDay+7-wd)/7);
j += 2;
}else{
sqlite3_snprintf(4, &z[j],"%03d",nDay+1);
j += 3;
}
break;
}
case 'J': {
sqlite3_snprintf(20, &z[j],"%.16g",x.iJD/86400000.0);
j+=sqlite3Strlen30(&z[j]);
break;
}
case 'm': sqlite3_snprintf(3, &z[j],"%02d",x.M); j+=2; break;
case 'M': sqlite3_snprintf(3, &z[j],"%02d",x.m); j+=2; break;
case 's': {
sqlite3_snprintf(30,&z[j],"%lld",
(i64)(x.iJD/1000 - 21086676*(i64)10000));
j += sqlite3Strlen30(&z[j]);
break;
}
case 'S': sqlite3_snprintf(3,&z[j],"%02d",(int)x.s); j+=2; break;
case 'w': {
z[j++] = (char)(((x.iJD+129600000)/86400000) % 7) + '0';
break;
}
case 'Y': {
sqlite3_snprintf(5,&z[j],"%04d",x.Y); j+=sqlite3Strlen30(&z[j]);
break;
}
default: z[j++] = '%'; break;
}
}
}
z[j] = 0;
sqlite3_result_text(context, z, -1,
z==zBuf ? SQLITE_TRANSIENT : SQLITE_DYNAMIC);
}
/*
** current_time()
**
** This function returns the same value as time('now').
*/
static void ctimeFunc(
sqlite3_context *context,
int NotUsed,
sqlite3_value **NotUsed2
){
UNUSED_PARAMETER2(NotUsed, NotUsed2);
timeFunc(context, 0, 0);
}
/*
** current_date()
**
** This function returns the same value as date('now').
*/
static void cdateFunc(
sqlite3_context *context,
int NotUsed,
sqlite3_value **NotUsed2
){
UNUSED_PARAMETER2(NotUsed, NotUsed2);
dateFunc(context, 0, 0);
}
/*
** current_timestamp()
**
** This function returns the same value as datetime('now').
*/
static void ctimestampFunc(
sqlite3_context *context,
int NotUsed,
sqlite3_value **NotUsed2
){
UNUSED_PARAMETER2(NotUsed, NotUsed2);
datetimeFunc(context, 0, 0);
}
#endif /* !defined(SQLITE_OMIT_DATETIME_FUNCS) */
#ifdef SQLITE_OMIT_DATETIME_FUNCS
/*
** If the library is compiled to omit the full-scale date and time
** handling (to get a smaller binary), the following minimal version
** of the functions current_time(), current_date() and current_timestamp()
** are included instead. This is to support column declarations that
** include "DEFAULT CURRENT_TIME" etc.
**
** This function uses the C-library functions time(), gmtime()
** and strftime(). The format string to pass to strftime() is supplied
** as the user-data for the function.
*/
static void currentTimeFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
time_t t;
char *zFormat = (char *)sqlite3_user_data(context);
sqlite3_int64 iT;
struct tm *pTm;
struct tm sNow;
char zBuf[20];
UNUSED_PARAMETER(argc);
UNUSED_PARAMETER(argv);
iT = sqlite3StmtCurrentTime(context);
if( iT<=0 ) return;
t = iT/1000 - 10000*(sqlite3_int64)21086676;
#if HAVE_GMTIME_R
pTm = gmtime_r(&t, &sNow);
#else
sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
pTm = gmtime(&t);
if( pTm ) memcpy(&sNow, pTm, sizeof(sNow));
sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
#endif
if( pTm ){
strftime(zBuf, 20, zFormat, &sNow);
sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
}
}
#endif
/*
** This function registered all of the above C functions as SQL
** functions. This should be the only routine in this file with
** external linkage.
*/
void sqlite3RegisterDateTimeFunctions(void){
static FuncDef aDateTimeFuncs[] = {
#ifndef SQLITE_OMIT_DATETIME_FUNCS
PURE_DATE(julianday, -1, 0, 0, juliandayFunc ),
PURE_DATE(date, -1, 0, 0, dateFunc ),
PURE_DATE(time, -1, 0, 0, timeFunc ),
PURE_DATE(datetime, -1, 0, 0, datetimeFunc ),
PURE_DATE(strftime, -1, 0, 0, strftimeFunc ),
DFUNCTION(current_time, 0, 0, 0, ctimeFunc ),
DFUNCTION(current_timestamp, 0, 0, 0, ctimestampFunc),
DFUNCTION(current_date, 0, 0, 0, cdateFunc ),
#else
STR_FUNCTION(current_time, 0, "%H:%M:%S", 0, currentTimeFunc),
STR_FUNCTION(current_date, 0, "%Y-%m-%d", 0, currentTimeFunc),
STR_FUNCTION(current_timestamp, 0, "%Y-%m-%d %H:%M:%S", 0, currentTimeFunc),
#endif
};
sqlite3InsertBuiltinFuncs(aDateTimeFuncs, ArraySize(aDateTimeFuncs));
}