Update of /cvsroot/wpdev/wolfpack/sqlite
In directory sc8-pr-cvs1:/tmp/cvs-serv5518
Modified Files:
attach.c auth.c btree.c btree.h btree_rb.c build.c config.h
copy.c delete.c expr.c func.c hash.c hash.h insert.c main.c
opcodes.c opcodes.h os.c pager.c pager.h parse.c parse.h
pragma.c random.c select.c sqlite.h sqliteInt.h table.c
tokenize.c trigger.c update.c util.c vacuum.c vdbe.c vdbe.h
where.c
Added Files:
date.c vdbeInt.h vdbeaux.c
Log Message:
Updated to current SQLite.
--- NEW FILE: date.c ---
/*
** 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
** sqliteRegisterDateTimeFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: date.c,v 1.1 2003/12/18 13:20:23 thiagocorrea Exp $
**
** NOTES:
**
** 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 implemention 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
** ISBM 0-943396-61-1
** Willmann-Bell, Inc
** Richmond, Virginia (USA)
*/
#ifndef SQLITE_OMIT_DATETIME_FUNCS
#include <ctype.h>
#include <stdlib.h>
#include <assert.h>
#include "sqliteInt.h"
#include "os.h"
/*
** A structure for holding a single date and time.
*/
typedef struct DateTime DateTime;
struct DateTime {
double rJD; /* The julian day number */
int Y, M, D; /* Year, month, and day */
int h, m; /* Hour and minutes */
int tz; /* Timezone offset in minutes */
double s; /* Seconds */
char validYMD; /* True if Y,M,D are valid */
char validHMS; /* True if h,m,s are valid */
char validJD; /* True if rJD is valid */
char validTZ; /* True if tz is valid */
};
/*
** Convert N digits from zDate into an integer. Return
** -1 if zDate does not begin with N digits.
*/
static int getDigits(const char *zDate, int N){
int val = 0;
while( N-- ){
if( !isdigit(*zDate) ) return -1;
val = val*10 + *zDate - '0';
zDate++;
}
return val;
}
/*
** Read text from z[] and convert into a floating point number. Return
** the number of digits converted.
*/
static int getValue(const char *z, double *pR){
double r = 0.0;
double rDivide = 1.0;
int isNeg = 0;
int nChar = 0;
if( *z=='+' ){
z++;
nChar++;
}else if( *z=='-' ){
z++;
isNeg = 1;
nChar++;
}
if( !isdigit(*z) ) return 0;
while( isdigit(*z) ){
r = r*10.0 + *z - '0';
nChar++;
z++;
}
if( *z=='.' && isdigit(z[1]) ){
z++;
nChar++;
while( isdigit(*z) ){
r = r*10.0 + *z - '0';
rDivide *= 10.0;
nChar++;
z++;
}
r /= rDivide;
}
if( *z!=0 && !isspace(*z) ) return 0;
*pR = isNeg ? -r : r;
return nChar;
}
/*
** Parse a timezone extension on the end of a date-time.
** The extension is of the form:
**
** (+/-)HH:MM
**
** If the parse is successful, write the number of minutes
** of change in *pnMin and return 0. If a parser error occurs,
** return 0.
**
** A missing specifier is not considered an error.
*/
static int parseTimezone(const char *zDate, DateTime *p){
int sgn = 0;
int nHr, nMn;
while( isspace(*zDate) ){ zDate++; }
p->tz = 0;
if( *zDate=='-' ){
sgn = -1;
}else if( *zDate=='+' ){
sgn = +1;
}else{
return *zDate!=0;
}
zDate++;
nHr = getDigits(zDate, 2);
if( nHr<0 || nHr>14 ) return 1;
zDate += 2;
if( zDate[0]!=':' ) return 1;
zDate++;
nMn = getDigits(zDate, 2);
if( nMn<0 || nMn>59 ) return 1;
zDate += 2;
p->tz = sgn*(nMn + nHr*60);
while( isspace(*zDate) ){ zDate++; }
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;
h = getDigits(zDate, 2);
if( h<0 || zDate[2]!=':' ) return 1;
zDate += 3;
m = getDigits(zDate, 2);
if( m<0 || m>59 ) return 1;
zDate += 2;
if( *zDate==':' ){
s = getDigits(&zDate[1], 2);
if( s<0 || s>59 ) return 1;
zDate += 3;
if( *zDate=='.' && isdigit(zDate[1]) ){
double rScale = 1.0;
zDate++;
while( isdigit(*zDate) ){
ms = ms*10.0 + *zDate - '0';
rScale *= 10.0;
zDate++;
}
ms /= rScale;
}
}else{
s = 0;
}
p->validJD = 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;
return 0;
}
/*
** 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;
M = 1;
D = 1;
}
if( M<=2 ){
Y--;
M += 12;
}
A = Y/100;
B = 2 - A + (A/4);
X1 = 365.25*(Y+4716);
X2 = 30.6001*(M+1);
p->rJD = X1 + X2 + D + B - 1524.5;
p->validJD = 1;
p->validYMD = 0;
if( p->validHMS ){
p->rJD += (p->h*3600.0 + p->m*60.0 + p->s)/86400.0;
if( p->validTZ ){
p->rJD += p->tz*60/86400.0;
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;
Y = getDigits(zDate, 4);
if( Y<0 || zDate[4]!='-' ) return 1;
zDate += 5;
M = getDigits(zDate, 2);
if( M<=0 || M>12 || zDate[2]!='-' ) return 1;
zDate += 3;
D = getDigits(zDate, 2);
if( D<=0 || D>31 ) return 1;
zDate += 2;
while( isspace(*zDate) ){ zDate++; }
if( isdigit(*zDate) ){
if( parseHhMmSs(zDate, p) ) return 1;
}else if( *zDate==0 ){
p->validHMS = 0;
}else{
return 1;
}
p->validJD = 0;
p->validYMD = 1;
p->Y = Y;
p->M = M;
p->D = D;
if( p->validTZ ){
computeJD(p);
}
return 0;
}
/*
** 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(const char *zDate, DateTime *p){
int i;
memset(p, 0, sizeof(*p));
for(i=0; isdigit(zDate[i]); i++){}
if( i==4 && zDate[i]=='-' ){
return parseYyyyMmDd(zDate, p);
}else if( i==2 && zDate[i]==':' ){
return parseHhMmSs(zDate, p);
return 0;
}else if( i==0 && sqliteStrICmp(zDate,"now")==0 ){
double r;
if( sqliteOsCurrentTime(&r)==0 ){
p->rJD = r;
p->validJD = 1;
return 0;
}
return 1;
}else if( sqliteIsNumber(zDate) ){
p->rJD = atof(zDate);
p->validJD = 1;
return 0;
}
return 1;
}
/*
** 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;
Z = p->rJD + 0.5;
A = (Z - 1867216.25)/36524.25;
A = Z + 1 + A - (A/4);
B = A + 1524;
C = (B - 122.1)/365.25;
D = 365.25*C;
E = (B-D)/30.6001;
X1 = 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 Z, s;
if( p->validHMS ) return;
Z = p->rJD + 0.5;
s = (p->rJD + 0.5 - Z)*86400000.0 + 0.5;
p->s = 0.001*s;
s = p->s;
p->s -= s;
p->h = s/3600;
s -= p->h*3600;
p->m = s/60;
p->s += s - p->m*60;
p->validHMS = 1;
}
/*
** 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
**
** Return 0 on success and 1 if there is any kind of error.
*/
static int parseModifier(const char *zMod, DateTime *p){
int rc = 1;
int n;
double r;
char z[30];
for(n=0; n<sizeof(z)-1; n++){
z[n] = tolower(zMod[n]);
}
z[n] = 0;
switch( z[0] ){
case 'u': {
/*
** unixepoch
**
** Treat the current value of p->rJD as the number of
** seconds since 1970. Convert to a real julian day number.
*/
if( strcmp(z, "unixepoch")==0 && p->validJD ){
p->rJD = p->rJD/86400.0 + 2440587.5;
p->validYMD = 0;
p->validHMS = 0;
p->validTZ = 0;
rc = 0;
}
break;
}
case 'w': {
/*
** weekday N
**
** Move the date to the beginning of the next occurrance of
** weekday N where 0==Sunday, 1==Monday, and so forth. If the
** date is already on the appropriate weekday, this is equivalent
** to "start of day".
*/
if( strncmp(z, "weekday ", 8)==0 && getValue(&z[8],&r)>0
&& (n=r)==r && n>=0 && r<7 ){
int Z;
computeYMD(p);
p->validHMS = 0;
p->validTZ = 0;
p->validJD = 0;
computeJD(p);
Z = p->rJD + 1.5;
Z %= 7;
if( Z>n ) Z -= 7;
p->rJD += n - Z;
p->validYMD = 0;
p->validHMS = 0;
rc = 0;
}
break;
}
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;
zMod = &z[9];
computeYMD(p);
p->validHMS = 1;
p->h = p->m = 0;
p->s = 0.0;
p->validTZ = 0;
p->validJD = 0;
if( strcmp(zMod,"month")==0 ){
p->D = 1;
rc = 0;
}else if( strcmp(zMod,"year")==0 ){
computeYMD(p);
p->M = 1;
p->D = 1;
rc = 0;
}else if( strcmp(zMod,"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': {
n = getValue(z, &r);
if( n<=0 ) break;
zMod = &z[n];
while( isspace(zMod[0]) ) zMod++;
n = strlen(zMod);
if( n>10 || n<3 ) break;
strcpy(z, zMod);
if( z[n-1]=='s' ){ z[n-1] = 0; n--; }
computeJD(p);
rc = 0;
if( n==3 && strcmp(z,"day")==0 ){
p->rJD += r;
}else if( n==4 && strcmp(z,"hour")==0 ){
computeJD(p);
p->rJD += r/24.0;
}else if( n==6 && strcmp(z,"minute")==0 ){
computeJD(p);
p->rJD += r/(24.0*60.0);
}else if( n==6 && strcmp(z,"second")==0 ){
computeJD(p);
p->rJD += r/(24.0*60.0*60.0);
}else if( n==5 && strcmp(z,"month")==0 ){
int x, y;
computeYMD(p);
p->M += 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 = r;
if( y!=r ){
p->rJD += (r - y)*30.0;
}
}else if( n==4 && strcmp(z,"year")==0 ){
computeYMD(p);
p->Y += r;
p->validJD = 0;
computeJD(p);
}else{
rc = 1;
}
p->validYMD = 0;
p->validHMS = 0;
p->validTZ = 0;
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.
*/
static int isDate(int argc, const char **argv, DateTime *p){
int i;
if( argc==0 ) return 1;
if( parseDateOrTime(argv[0], p) ) return 1;
for(i=1; i<argc; i++){
if( parseModifier(argv[i], p) ) 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(sqlite_func *context, int argc, const char **argv){
DateTime x;
if( isDate(argc, argv, &x)==0 ){
computeJD(&x);
sqlite_set_result_double(context, x.rJD);
}
}
/*
** datetime( TIMESTRING, MOD, MOD, ...)
**
** Return YYYY-MM-DD HH:MM:SS
*/
static void datetimeFunc(sqlite_func *context, int argc, const char **argv){
DateTime x;
if( isDate(argc, argv, &x)==0 ){
char zBuf[100];
computeYMD(&x);
computeHMS(&x);
sprintf(zBuf, "%04d-%02d-%02d %02d:%02d:%02d",x.Y, x.M, x.D, x.h, x.m,
(int)(x.s));
sqlite_set_result_string(context, zBuf, -1);
}
}
/*
** time( TIMESTRING, MOD, MOD, ...)
**
** Return HH:MM:SS
*/
static void timeFunc(sqlite_func *context, int argc, const char **argv){
DateTime x;
if( isDate(argc, argv, &x)==0 ){
char zBuf[100];
computeHMS(&x);
sprintf(zBuf, "%02d:%02d:%02d", x.h, x.m, (int)x.s);
sqlite_set_result_string(context, zBuf, -1);
}
}
/*
** date( TIMESTRING, MOD, MOD, ...)
**
** Return YYYY-MM-DD
*/
static void dateFunc(sqlite_func *context, int argc, const char **argv){
DateTime x;
if( isDate(argc, argv, &x)==0 ){
char zBuf[100];
computeYMD(&x);
sprintf(zBuf, "%04d-%02d-%02d", x.Y, x.M, x.D);
sqlite_set_result_string(context, zBuf, -1);
}
}
/*
** 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(sqlite_func *context, int argc, const char **argv){
DateTime x;
int n, i, j;
char *z;
const char *zFmt = argv[0];
char zBuf[100];
if( isDate(argc-1, argv+1, &x) ) return;
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++;
}
}
if( n<sizeof(zBuf) ){
z = zBuf;
}else{
z = sqliteMalloc( n );
if( z==0 ) return;
}
computeJD(&x);
computeYMD(&x);
computeHMS(&x);
for(i=j=0; zFmt[i]; i++){
if( zFmt[i]!='%' ){
z[j++] = zFmt[i];
}else{
i++;
switch( zFmt[i] ){
case 'd': sprintf(&z[j],"%02d",x.D); j+=2; break;
case 'f': {
int s = x.s;
int ms = (x.s - s)*1000.0;
sprintf(&z[j],"%02d.%03d",s,ms);
j += strlen(&z[j]);
break;
}
case 'H': sprintf(&z[j],"%02d",x.h); j+=2; break;
case 'W': /* Fall thru */
case 'j': {
int n;
DateTime y = x;
y.validJD = 0;
y.M = 1;
y.D = 1;
computeJD(&y);
n = x.rJD - y.rJD + 1;
if( zFmt[i]=='W' ){
sprintf(&z[j],"%02d",(n+6)/7);
j += 2;
}else{
sprintf(&z[j],"%03d",n);
j += 3;
}
break;
}
case 'J': sprintf(&z[j],"%.16g",x.rJD); j+=strlen(&z[j]); break;
case 'm': sprintf(&z[j],"%02d",x.M); j+=2; break;
case 'M': sprintf(&z[j],"%02d",x.m); j+=2; break;
case 's': {
sprintf(&z[j],"%d",(int)((x.rJD-2440587.5)*86400.0));
j += strlen(&z[j]);
break;
}
case 'S': sprintf(&z[j],"%02d",(int)x.s); j+=2; break;
case 'w': z[j++] = (((int)(x.rJD+1.5)) % 7) + '0'; break;
case 'Y': sprintf(&z[j],"%04d",x.Y); j+=strlen(&z[j]); break;
case '%': z[j++] = '%'; break;
}
}
}
z[j] = 0;
sqlite_set_result_string(context, z, -1);
if( z!=zBuf ){
sqliteFree(z);
}
}
#endif /* !defined(SQLITE_OMIT_DATETIME_FUNCS) */
/*
** 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 sqliteRegisterDateTimeFunctions(sqlite *db){
static struct {
char *zName;
int nArg;
int dataType;
void (*xFunc)(sqlite_func*,int,const char**);
} aFuncs[] = {
#ifndef SQLITE_OMIT_DATETIME_FUNCS
{ "julianday", -1, SQLITE_NUMERIC, juliandayFunc },
{ "date", -1, SQLITE_TEXT, dateFunc },
{ "time", 1, SQLITE_TEXT, timeFunc },
{ "datetime", -1, SQLITE_TEXT, datetimeFunc },
{ "strftime", -1, SQLITE_TEXT, strftimeFunc },
#endif
};
int i;
for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
sqlite_create_function(db, aFuncs[i].zName,
aFuncs[i].nArg, aFuncs[i].xFunc, 0);
if( aFuncs[i].xFunc ){
sqlite_function_type(db, aFuncs[i].zName, aFuncs[i].dataType);
}
}
}
--- NEW FILE: vdbeInt.h ---
/*
** 2003 September 6
**
** 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 is the header file for information that is private to the
** VDBE. This information used to all be at the top of the single
** source code file "vdbe.c". When that file became too big (over
** 6000 lines long) it was split up into several smaller files and
** this header information was factored out.
*/
/*
** The makefile scans this source file and creates the following
** array of string constants which are the names of all VDBE opcodes.
** This array is defined in a separate source code file named opcode.c
** which is automatically generated by the makefile.
*/
extern char *sqliteOpcodeNames[];
/*
** SQL is translated into a sequence of instructions to be
** executed by a virtual machine. Each instruction is an instance
** of the following structure.
*/
typedef struct VdbeOp Op;
/*
** Boolean values
*/
typedef unsigned char Bool;
/*
** A cursor is a pointer into a single BTree within a database file.
** The cursor can seek to a BTree entry with a particular key, or
** loop over all entries of the Btree. You can also insert new BTree
** entries or retrieve the key or data from the entry that the cursor
** is currently pointing to.
**
** Every cursor that the virtual machine has open is represented by an
** instance of the following structure.
**
** If the Cursor.isTriggerRow flag is set it means that this cursor is
** really a single row that represents the NEW or OLD pseudo-table of
** a row trigger. The data for the row is stored in Cursor.pData and
** the rowid is in Cursor.iKey.
*/
struct Cursor {
BtCursor *pCursor; /* The cursor structure of the backend */
int lastRecno; /* Last recno from a Next or NextIdx operation */
int nextRowid; /* Next rowid returned by OP_NewRowid */
Bool recnoIsValid; /* True if lastRecno is valid */
Bool keyAsData; /* The OP_Column command works on key instead of data */
Bool atFirst; /* True if pointing to first entry */
Bool useRandomRowid; /* Generate new record numbers semi-randomly */
Bool nullRow; /* True if pointing to a row with no data */
Bool nextRowidValid; /* True if the nextRowid field is valid */
Bool pseudoTable; /* This is a NEW or OLD pseudo-tables of a trigger */
Btree *pBt; /* Separate file holding temporary table */
int nData; /* Number of bytes in pData */
char *pData; /* Data for a NEW or OLD pseudo-table */
int iKey; /* Key for the NEW or OLD pseudo-table row */
};
typedef struct Cursor Cursor;
/*
** A sorter builds a list of elements to be sorted. Each element of
** the list is an instance of the following structure.
*/
typedef struct Sorter Sorter;
struct Sorter {
int nKey; /* Number of bytes in the key */
char *zKey; /* The key by which we will sort */
int nData; /* Number of bytes in the data */
char *pData; /* The data associated with this key */
Sorter *pNext; /* Next in the list */
};
/*
** Number of buckets used for merge-sort.
*/
#define NSORT 30
/*
** Number of bytes of string storage space available to each stack
** layer without having to malloc. NBFS is short for Number of Bytes
** For Strings.
*/
#define NBFS 32
/*
** A single level of the stack is an instance of the following
** structure. Except, string values are stored on a separate
** list of of pointers to character. The reason for storing
** strings separately is so that they can be easily passed
** to the callback function.
*/
struct Stack {
int i; /* Integer value */
int n; /* Number of characters in string value, including '\0' */
int flags; /* Some combination of STK_Null, STK_Str, STK_Dyn, etc. */
double r; /* Real value */
char z[NBFS]; /* Space for short strings */
};
typedef struct Stack Stack;
/*
** Memory cells use the same structure as the stack except that space
** for an arbitrary string is added.
*/
struct Mem {
Stack s; /* All values of the memory cell besides string */
char *z; /* String value for this memory cell */
};
typedef struct Mem Mem;
/*
** Allowed values for Stack.flags
*/
#define STK_Null 0x0001 /* Value is NULL */
#define STK_Str 0x0002 /* Value is a string */
#define STK_Int 0x0004 /* Value is an integer */
#define STK_Real 0x0008 /* Value is a real number */
#define STK_Dyn 0x0010 /* Need to call sqliteFree() on zStack[] */
#define STK_Static 0x0020 /* zStack[] points to a static string */
#define STK_Ephem 0x0040 /* zStack[] points to an ephemeral string */
/* The following STK_ value appears only in AggElem.aMem.s.flag fields.
** It indicates that the corresponding AggElem.aMem.z points to a
** aggregate function context that needs to be finalized.
*/
#define STK_AggCtx 0x0040 /* zStack[] points to an agg function context */
/*
** The "context" argument for a installable function. A pointer to an
** instance of this structure is the first argument to the routines used
** implement the SQL functions.
**
** There is a typedef for this structure in sqlite.h. So all routines,
** even the public interface to SQLite, can use a pointer to this structure.
** But this file is the only place where the internal details of this
** structure are known.
**
** This structure is defined inside of vdbe.c because it uses substructures
** (Stack) which are only defined there.
*/
struct sqlite_func {
FuncDef *pFunc; /* Pointer to function information. MUST BE FIRST */
Stack s; /* Small strings, ints, and double values go here */
char *z; /* Space for holding dynamic string results */
void *pAgg; /* Aggregate context */
u8 isError; /* Set to true for an error */
u8 isStep; /* Current in the step function */
int cnt; /* Number of times that the step function has been called */
};
/*
** An Agg structure describes an Aggregator. Each Agg consists of
** zero or more Aggregator elements (AggElem). Each AggElem contains
** a key and one or more values. The values are used in processing
** aggregate functions in a SELECT. The key is used to implement
** the GROUP BY clause of a select.
*/
typedef struct Agg Agg;
typedef struct AggElem AggElem;
struct Agg {
int nMem; /* Number of values stored in each AggElem */
AggElem *pCurrent; /* The AggElem currently in focus */
HashElem *pSearch; /* The hash element for pCurrent */
Hash hash; /* Hash table of all aggregate elements */
FuncDef **apFunc; /* Information about aggregate functions */
};
struct AggElem {
char *zKey; /* The key to this AggElem */
int nKey; /* Number of bytes in the key, including '\0' at end */
Mem aMem[1]; /* The values for this AggElem */
};
/*
** A Set structure is used for quick testing to see if a value
** is part of a small set. Sets are used to implement code like
** this:
** x.y IN ('hi','hoo','hum')
*/
typedef struct Set Set;
struct Set {
Hash hash; /* A set is just a hash table */
HashElem *prev; /* Previously accessed hash elemen */
};
/*
** A Keylist is a bunch of keys into a table. The keylist can
** grow without bound. The keylist stores the ROWIDs of database
** records that need to be deleted or updated.
*/
typedef struct Keylist Keylist;
struct Keylist {
int nKey; /* Number of slots in aKey[] */
int nUsed; /* Next unwritten slot in aKey[] */
int nRead; /* Next unread slot in aKey[] */
Keylist *pNext; /* Next block of keys */
int aKey[1]; /* One or more keys. Extra space allocated as needed */
};
/*
** An instance of the virtual machine. This structure contains the complete
** state of the virtual machine.
**
** The "sqlite_vm" structure pointer that is returned by sqlite_compile()
** is really a pointer to an instance of this structure.
*/
struct Vdbe {
sqlite *db; /* The whole database */
Vdbe *pPrev,*pNext; /* Linked list of VDBEs with the same Vdbe.db */
FILE *trace; /* Write an execution trace here, if not NULL */
int nOp; /* Number of instructions in the program */
int nOpAlloc; /* Number of slots allocated for aOp[] */
Op *aOp; /* Space to hold the virtual machine's program */
int nLabel; /* Number of labels used */
int nLabelAlloc; /* Number of slots allocated in aLabel[] */
int *aLabel; /* Space to hold the labels */
int tos; /* Index of top of stack */
Stack *aStack; /* The operand stack, except string values */
char **zStack; /* Text or binary values of the stack */
char **azColName; /* Becomes the 4th parameter to callbacks */
int nCursor; /* Number of slots in aCsr[] */
Cursor *aCsr; /* One element of this array for each open cursor */
Sorter *pSort; /* A linked list of objects to be sorted */
FILE *pFile; /* At most one open file handler */
int nField; /* Number of file fields */
char **azField; /* Data for each file field */
int nVar; /* Number of entries in azVariable[] */
char **azVar; /* Values for the OP_Variable opcode */
int *anVar; /* Length of each value in azVariable[] */
u8 *abVar; /* TRUE if azVariable[i] needs to be sqliteFree()ed */
char *zLine; /* A single line from the input file */
int nLineAlloc; /* Number of spaces allocated for zLine */
int magic; /* Magic number for sanity checking */
int nMem; /* Number of memory locations currently allocated */
Mem *aMem; /* The memory locations */
Agg agg; /* Aggregate information */
int nSet; /* Number of sets allocated */
Set *aSet; /* An array of sets */
int nCallback; /* Number of callbacks invoked so far */
Keylist *pList; /* A list of ROWIDs */
int keylistStackDepth; /* The size of the "keylist" stack */
Keylist **keylistStack; /* The stack used by opcodes ListPush & ListPop */
int pc; /* The program counter */
int rc; /* Value to return */
unsigned uniqueCnt; /* Used by OP_MakeRecord when P2!=0 */
int errorAction; /* Recovery action to do in case of an error */
int undoTransOnError; /* If error, either ROLLBACK or COMMIT */
int inTempTrans; /* True if temp database is transactioned */
int returnStack[100]; /* Return address stack for OP_Gosub & OP_Return */
int returnDepth; /* Next unused element in returnStack[] */
int nResColumn; /* Number of columns in one row of the result set */
char **azResColumn; ...
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