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a46ba6cca5102ade4689faeb67a499d56360ebb7
sqlite/src/vdbemem.c
T
drh 9201184711 Store application-defined function names as lower-case to avoid the need 
for case conversions before calling xFindFunction on virtual tables.
Avoid using lookaside to store the destructors for application defined
functions, as lookaside should be reserved for transient allocations.

FossilOrigin-Name: 777189ce88799f93f393fd14fd716111c85bcdcb23690fd561f78ea2bd2ce5da
2018-05-26 16:00:26 +00:00

1841 lines
58 KiB
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/*
** 2004 May 26
**
** 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 code use to manipulate "Mem" structure. A "Mem"
** stores a single value in the VDBE. Mem is an opaque structure visible
** only within the VDBE. Interface routines refer to a Mem using the
** name sqlite_value
*/
#include "sqliteInt.h"
#include "vdbeInt.h"
#ifdef SQLITE_DEBUG
/*
** Check invariants on a Mem object.
**
** This routine is intended for use inside of assert() statements, like
** this: assert( sqlite3VdbeCheckMemInvariants(pMem) );
*/
int sqlite3VdbeCheckMemInvariants(Mem *p){
/* If MEM_Dyn is set then Mem.xDel!=0.
** Mem.xDel might not be initialized if MEM_Dyn is clear.
*/
assert( (p->flags & MEM_Dyn)==0 || p->xDel!=0 );
/* MEM_Dyn may only be set if Mem.szMalloc==0. In this way we
** ensure that if Mem.szMalloc>0 then it is safe to do
** Mem.z = Mem.zMalloc without having to check Mem.flags&MEM_Dyn.
** That saves a few cycles in inner loops. */
assert( (p->flags & MEM_Dyn)==0 || p->szMalloc==0 );
/* Cannot be both MEM_Int and MEM_Real at the same time */
assert( (p->flags & (MEM_Int|MEM_Real))!=(MEM_Int|MEM_Real) );
if( p->flags & MEM_Null ){
/* Cannot be both MEM_Null and some other type */
assert( (p->flags & (MEM_Int|MEM_Real|MEM_Str|MEM_Blob
|MEM_RowSet|MEM_Frame|MEM_Agg))==0 );
/* If MEM_Null is set, then either the value is a pure NULL (the usual
** case) or it is a pointer set using sqlite3_bind_pointer() or
** sqlite3_result_pointer(). If a pointer, then MEM_Term must also be
** set.
*/
if( (p->flags & (MEM_Term|MEM_Subtype))==(MEM_Term|MEM_Subtype) ){
/* This is a pointer type. There may be a flag to indicate what to
** do with the pointer. */
assert( ((p->flags&MEM_Dyn)!=0 ? 1 : 0) +
((p->flags&MEM_Ephem)!=0 ? 1 : 0) +
((p->flags&MEM_Static)!=0 ? 1 : 0) <= 1 );
/* No other bits set */
assert( (p->flags & ~(MEM_Null|MEM_Term|MEM_Subtype
|MEM_Dyn|MEM_Ephem|MEM_Static))==0 );
}else{
/* A pure NULL might have other flags, such as MEM_Static, MEM_Dyn,
** MEM_Ephem, MEM_Cleared, or MEM_Subtype */
}
}else{
/* The MEM_Cleared bit is only allowed on NULLs */
assert( (p->flags & MEM_Cleared)==0 );
}
/* The szMalloc field holds the correct memory allocation size */
assert( p->szMalloc==0
|| p->szMalloc==sqlite3DbMallocSize(p->db,p->zMalloc) );
/* If p holds a string or blob, the Mem.z must point to exactly
** one of the following:
**
** (1) Memory in Mem.zMalloc and managed by the Mem object
** (2) Memory to be freed using Mem.xDel
** (3) An ephemeral string or blob
** (4) A static string or blob
*/
if( (p->flags & (MEM_Str|MEM_Blob)) && p->n>0 ){
assert(
((p->szMalloc>0 && p->z==p->zMalloc)? 1 : 0) +
((p->flags&MEM_Dyn)!=0 ? 1 : 0) +
((p->flags&MEM_Ephem)!=0 ? 1 : 0) +
((p->flags&MEM_Static)!=0 ? 1 : 0) == 1
);
}
return 1;
}
#endif
#ifdef SQLITE_DEBUG
/*
** Check that string value of pMem agrees with its integer or real value.
**
** A single int or real value always converts to the same strings. But
** many different strings can be converted into the same int or real.
** If a table contains a numeric value and an index is based on the
** corresponding string value, then it is important that the string be
** derived from the numeric value, not the other way around, to ensure
** that the index and table are consistent. See ticket
** https://www.sqlite.org/src/info/343634942dd54ab (2018-01-31) for
** an example.
**
** This routine looks at pMem to verify that if it has both a numeric
** representation and a string representation then the string rep has
** been derived from the numeric and not the other way around. It returns
** true if everything is ok and false if there is a problem.
**
** This routine is for use inside of assert() statements only.
*/
int sqlite3VdbeMemConsistentDualRep(Mem *p){
char zBuf[100];
char *z;
int i, j, incr;
if( (p->flags & MEM_Str)==0 ) return 1;
if( (p->flags & (MEM_Int|MEM_Real))==0 ) return 1;
if( p->flags & MEM_Int ){
sqlite3_snprintf(sizeof(zBuf),zBuf,"%lld",p->u.i);
}else{
sqlite3_snprintf(sizeof(zBuf),zBuf,"%!.15g",p->u.r);
}
z = p->z;
i = j = 0;
incr = 1;
if( p->enc!=SQLITE_UTF8 ){
incr = 2;
if( p->enc==SQLITE_UTF16BE ) z++;
}
while( zBuf[j] ){
if( zBuf[j++]!=z[i] ) return 0;
i += incr;
}
return 1;
}
#endif /* SQLITE_DEBUG */
/*
** If pMem is an object with a valid string representation, this routine
** ensures the internal encoding for the string representation is
** 'desiredEnc', one of SQLITE_UTF8, SQLITE_UTF16LE or SQLITE_UTF16BE.
**
** If pMem is not a string object, or the encoding of the string
** representation is already stored using the requested encoding, then this
** routine is a no-op.
**
** SQLITE_OK is returned if the conversion is successful (or not required).
** SQLITE_NOMEM may be returned if a malloc() fails during conversion
** between formats.
*/
int sqlite3VdbeChangeEncoding(Mem *pMem, int desiredEnc){
#ifndef SQLITE_OMIT_UTF16
int rc;
#endif
assert( (pMem->flags&MEM_RowSet)==0 );
assert( desiredEnc==SQLITE_UTF8 || desiredEnc==SQLITE_UTF16LE
|| desiredEnc==SQLITE_UTF16BE );
if( !(pMem->flags&MEM_Str) || pMem->enc==desiredEnc ){
return SQLITE_OK;
}
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
#ifdef SQLITE_OMIT_UTF16
return SQLITE_ERROR;
#else
/* MemTranslate() may return SQLITE_OK or SQLITE_NOMEM. If NOMEM is returned,
** then the encoding of the value may not have changed.
*/
rc = sqlite3VdbeMemTranslate(pMem, (u8)desiredEnc);
assert(rc==SQLITE_OK || rc==SQLITE_NOMEM);
assert(rc==SQLITE_OK || pMem->enc!=desiredEnc);
assert(rc==SQLITE_NOMEM || pMem->enc==desiredEnc);
return rc;
#endif
}
/*
** Make sure pMem->z points to a writable allocation of at least
** min(n,32) bytes.
**
** If the bPreserve argument is true, then copy of the content of
** pMem->z into the new allocation. pMem must be either a string or
** blob if bPreserve is true. If bPreserve is false, any prior content
** in pMem->z is discarded.
*/
SQLITE_NOINLINE int sqlite3VdbeMemGrow(Mem *pMem, int n, int bPreserve){
assert( sqlite3VdbeCheckMemInvariants(pMem) );
assert( (pMem->flags&MEM_RowSet)==0 );
testcase( pMem->db==0 );
/* If the bPreserve flag is set to true, then the memory cell must already
** contain a valid string or blob value. */
assert( bPreserve==0 || pMem->flags&(MEM_Blob|MEM_Str) );
testcase( bPreserve && pMem->z==0 );
assert( pMem->szMalloc==0
|| pMem->szMalloc==sqlite3DbMallocSize(pMem->db, pMem->zMalloc) );
if( n<32 ) n = 32;
if( pMem->szMalloc>0 && bPreserve && pMem->z==pMem->zMalloc ){
pMem->z = pMem->zMalloc = sqlite3DbReallocOrFree(pMem->db, pMem->z, n);
bPreserve = 0;
}else{
if( pMem->szMalloc>0 ) sqlite3DbFreeNN(pMem->db, pMem->zMalloc);
pMem->zMalloc = sqlite3DbMallocRaw(pMem->db, n);
}
if( pMem->zMalloc==0 ){
sqlite3VdbeMemSetNull(pMem);
pMem->z = 0;
pMem->szMalloc = 0;
return SQLITE_NOMEM_BKPT;
}else{
pMem->szMalloc = sqlite3DbMallocSize(pMem->db, pMem->zMalloc);
}
if( bPreserve && pMem->z ){
assert( pMem->z!=pMem->zMalloc );
memcpy(pMem->zMalloc, pMem->z, pMem->n);
}
if( (pMem->flags&MEM_Dyn)!=0 ){
assert( pMem->xDel!=0 && pMem->xDel!=SQLITE_DYNAMIC );
pMem->xDel((void *)(pMem->z));
}
pMem->z = pMem->zMalloc;
pMem->flags &= ~(MEM_Dyn|MEM_Ephem|MEM_Static);
return SQLITE_OK;
}
/*
** Change the pMem->zMalloc allocation to be at least szNew bytes.
** If pMem->zMalloc already meets or exceeds the requested size, this
** routine is a no-op.
**
** Any prior string or blob content in the pMem object may be discarded.
** The pMem->xDel destructor is called, if it exists. Though MEM_Str
** and MEM_Blob values may be discarded, MEM_Int, MEM_Real, and MEM_Null
** values are preserved.
**
** Return SQLITE_OK on success or an error code (probably SQLITE_NOMEM)
** if unable to complete the resizing.
*/
int sqlite3VdbeMemClearAndResize(Mem *pMem, int szNew){
assert( szNew>0 );
assert( (pMem->flags & MEM_Dyn)==0 || pMem->szMalloc==0 );
if( pMem->szMalloc<szNew ){
return sqlite3VdbeMemGrow(pMem, szNew, 0);
}
assert( (pMem->flags & MEM_Dyn)==0 );
pMem->z = pMem->zMalloc;
pMem->flags &= (MEM_Null|MEM_Int|MEM_Real);
return SQLITE_OK;
}
/*
** It is already known that pMem contains an unterminated string.
** Add the zero terminator.
*/
static SQLITE_NOINLINE int vdbeMemAddTerminator(Mem *pMem){
if( sqlite3VdbeMemGrow(pMem, pMem->n+2, 1) ){
return SQLITE_NOMEM_BKPT;
}
pMem->z[pMem->n] = 0;
pMem->z[pMem->n+1] = 0;
pMem->flags |= MEM_Term;
return SQLITE_OK;
}
/*
** Change pMem so that its MEM_Str or MEM_Blob value is stored in
** MEM.zMalloc, where it can be safely written.
**
** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
*/
int sqlite3VdbeMemMakeWriteable(Mem *pMem){
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
assert( (pMem->flags&MEM_RowSet)==0 );
if( (pMem->flags & (MEM_Str|MEM_Blob))!=0 ){
if( ExpandBlob(pMem) ) return SQLITE_NOMEM;
if( pMem->szMalloc==0 || pMem->z!=pMem->zMalloc ){
int rc = vdbeMemAddTerminator(pMem);
if( rc ) return rc;
}
}
pMem->flags &= ~MEM_Ephem;
#ifdef SQLITE_DEBUG
pMem->pScopyFrom = 0;
#endif
return SQLITE_OK;
}
/*
** If the given Mem* has a zero-filled tail, turn it into an ordinary
** blob stored in dynamically allocated space.
*/
#ifndef SQLITE_OMIT_INCRBLOB
int sqlite3VdbeMemExpandBlob(Mem *pMem){
int nByte;
assert( pMem->flags & MEM_Zero );
assert( pMem->flags&MEM_Blob );
assert( (pMem->flags&MEM_RowSet)==0 );
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
/* Set nByte to the number of bytes required to store the expanded blob. */
nByte = pMem->n + pMem->u.nZero;
if( nByte<=0 ){
nByte = 1;
}
if( sqlite3VdbeMemGrow(pMem, nByte, 1) ){
return SQLITE_NOMEM_BKPT;
}
memset(&pMem->z[pMem->n], 0, pMem->u.nZero);
pMem->n += pMem->u.nZero;
pMem->flags &= ~(MEM_Zero|MEM_Term);
return SQLITE_OK;
}
#endif
/*
** Make sure the given Mem is \u0000 terminated.
*/
int sqlite3VdbeMemNulTerminate(Mem *pMem){
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
testcase( (pMem->flags & (MEM_Term|MEM_Str))==(MEM_Term|MEM_Str) );
testcase( (pMem->flags & (MEM_Term|MEM_Str))==0 );
if( (pMem->flags & (MEM_Term|MEM_Str))!=MEM_Str ){
return SQLITE_OK; /* Nothing to do */
}else{
return vdbeMemAddTerminator(pMem);
}
}
/*
** Add MEM_Str to the set of representations for the given Mem. Numbers
** are converted using sqlite3_snprintf(). Converting a BLOB to a string
** is a no-op.
**
** Existing representations MEM_Int and MEM_Real are invalidated if
** bForce is true but are retained if bForce is false.
**
** A MEM_Null value will never be passed to this function. This function is
** used for converting values to text for returning to the user (i.e. via
** sqlite3_value_text()), or for ensuring that values to be used as btree
** keys are strings. In the former case a NULL pointer is returned the
** user and the latter is an internal programming error.
*/
int sqlite3VdbeMemStringify(Mem *pMem, u8 enc, u8 bForce){
int fg = pMem->flags;
const int nByte = 32;
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
assert( !(fg&MEM_Zero) );
assert( !(fg&(MEM_Str|MEM_Blob)) );
assert( fg&(MEM_Int|MEM_Real) );
assert( (pMem->flags&MEM_RowSet)==0 );
assert( EIGHT_BYTE_ALIGNMENT(pMem) );
if( sqlite3VdbeMemClearAndResize(pMem, nByte) ){
pMem->enc = 0;
return SQLITE_NOMEM_BKPT;
}
/* For a Real or Integer, use sqlite3_snprintf() to produce the UTF-8
** string representation of the value. Then, if the required encoding
** is UTF-16le or UTF-16be do a translation.
**
** FIX ME: It would be better if sqlite3_snprintf() could do UTF-16.
*/
if( fg & MEM_Int ){
sqlite3_snprintf(nByte, pMem->z, "%lld", pMem->u.i);
}else{
assert( fg & MEM_Real );
sqlite3_snprintf(nByte, pMem->z, "%!.15g", pMem->u.r);
}
pMem->n = sqlite3Strlen30(pMem->z);
pMem->enc = SQLITE_UTF8;
pMem->flags |= MEM_Str|MEM_Term;
if( bForce ) pMem->flags &= ~(MEM_Int|MEM_Real);
sqlite3VdbeChangeEncoding(pMem, enc);
return SQLITE_OK;
}
/*
** Memory cell pMem contains the context of an aggregate function.
** This routine calls the finalize method for that function. The
** result of the aggregate is stored back into pMem.
**
** Return SQLITE_ERROR if the finalizer reports an error. SQLITE_OK
** otherwise.
*/
int sqlite3VdbeMemFinalize(Mem *pMem, FuncDef *pFunc){
sqlite3_context ctx;
Mem t;
assert( pFunc!=0 );
assert( pFunc->xFinalize!=0 );
assert( (pMem->flags & MEM_Null)!=0 || pFunc==pMem->u.pDef );
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
memset(&ctx, 0, sizeof(ctx));
memset(&t, 0, sizeof(t));
t.flags = MEM_Null;
t.db = pMem->db;
ctx.pOut = &t;
ctx.pMem = pMem;
ctx.pFunc = pFunc;
pFunc->xFinalize(&ctx); /* IMP: R-24505-23230 */
assert( (pMem->flags & MEM_Dyn)==0 );
if( pMem->szMalloc>0 ) sqlite3DbFreeNN(pMem->db, pMem->zMalloc);
memcpy(pMem, &t, sizeof(t));
return ctx.isError;
}
/*
** If the memory cell contains a value that must be freed by
** invoking the external callback in Mem.xDel, then this routine
** will free that value. It also sets Mem.flags to MEM_Null.
**
** This is a helper routine for sqlite3VdbeMemSetNull() and
** for sqlite3VdbeMemRelease(). Use those other routines as the
** entry point for releasing Mem resources.
*/
static SQLITE_NOINLINE void vdbeMemClearExternAndSetNull(Mem *p){
assert( p->db==0 || sqlite3_mutex_held(p->db->mutex) );
assert( VdbeMemDynamic(p) );
if( p->flags&MEM_Agg ){
sqlite3VdbeMemFinalize(p, p->u.pDef);
assert( (p->flags & MEM_Agg)==0 );
testcase( p->flags & MEM_Dyn );
}
if( p->flags&MEM_Dyn ){
assert( (p->flags&MEM_RowSet)==0 );
assert( p->xDel!=SQLITE_DYNAMIC && p->xDel!=0 );
p->xDel((void *)p->z);
}else if( p->flags&MEM_RowSet ){
sqlite3RowSetClear(p->u.pRowSet);
}else if( p->flags&MEM_Frame ){
VdbeFrame *pFrame = p->u.pFrame;
pFrame->pParent = pFrame->v->pDelFrame;
pFrame->v->pDelFrame = pFrame;
}
p->flags = MEM_Null;
}
/*
** Release memory held by the Mem p, both external memory cleared
** by p->xDel and memory in p->zMalloc.
**
** This is a helper routine invoked by sqlite3VdbeMemRelease() in
** the unusual case where there really is memory in p that needs
** to be freed.
*/
static SQLITE_NOINLINE void vdbeMemClear(Mem *p){
if( VdbeMemDynamic(p) ){
vdbeMemClearExternAndSetNull(p);
}
if( p->szMalloc ){
sqlite3DbFreeNN(p->db, p->zMalloc);
p->szMalloc = 0;
}
p->z = 0;
}
/*
** Release any memory resources held by the Mem. Both the memory that is
** free by Mem.xDel and the Mem.zMalloc allocation are freed.
**
** Use this routine prior to clean up prior to abandoning a Mem, or to
** reset a Mem back to its minimum memory utilization.
**
** Use sqlite3VdbeMemSetNull() to release just the Mem.xDel space
** prior to inserting new content into the Mem.
*/
void sqlite3VdbeMemRelease(Mem *p){
assert( sqlite3VdbeCheckMemInvariants(p) );
if( VdbeMemDynamic(p) || p->szMalloc ){
vdbeMemClear(p);
}
}
/*
** Convert a 64-bit IEEE double into a 64-bit signed integer.
** If the double is out of range of a 64-bit signed integer then
** return the closest available 64-bit signed integer.
*/
static SQLITE_NOINLINE i64 doubleToInt64(double r){
#ifdef SQLITE_OMIT_FLOATING_POINT
/* When floating-point is omitted, double and int64 are the same thing */
return r;
#else
/*
** Many compilers we encounter do not define constants for the
** minimum and maximum 64-bit integers, or they define them
** inconsistently. And many do not understand the "LL" notation.
** So we define our own static constants here using nothing
** larger than a 32-bit integer constant.
*/
static const i64 maxInt = LARGEST_INT64;
static const i64 minInt = SMALLEST_INT64;
if( r<=(double)minInt ){
return minInt;
}else if( r>=(double)maxInt ){
return maxInt;
}else{
return (i64)r;
}
#endif
}
/*
** Return some kind of integer value which is the best we can do
** at representing the value that *pMem describes as an integer.
** If pMem is an integer, then the value is exact. If pMem is
** a floating-point then the value returned is the integer part.
** If pMem is a string or blob, then we make an attempt to convert
** it into an integer and return that. If pMem represents an
** an SQL-NULL value, return 0.
**
** If pMem represents a string value, its encoding might be changed.
*/
static SQLITE_NOINLINE i64 memIntValue(Mem *pMem){
i64 value = 0;
sqlite3Atoi64(pMem->z, &value, pMem->n, pMem->enc);
return value;
}
i64 sqlite3VdbeIntValue(Mem *pMem){
int flags;
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
assert( EIGHT_BYTE_ALIGNMENT(pMem) );
flags = pMem->flags;
if( flags & MEM_Int ){
return pMem->u.i;
}else if( flags & MEM_Real ){
return doubleToInt64(pMem->u.r);
}else if( flags & (MEM_Str|MEM_Blob) ){
assert( pMem->z || pMem->n==0 );
return memIntValue(pMem);
}else{
return 0;
}
}
/*
** Return the best representation of pMem that we can get into a
** double. If pMem is already a double or an integer, return its
** value. If it is a string or blob, try to convert it to a double.
** If it is a NULL, return 0.0.
*/
static SQLITE_NOINLINE double memRealValue(Mem *pMem){
/* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
double val = (double)0;
sqlite3AtoF(pMem->z, &val, pMem->n, pMem->enc);
return val;
}
double sqlite3VdbeRealValue(Mem *pMem){
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
assert( EIGHT_BYTE_ALIGNMENT(pMem) );
if( pMem->flags & MEM_Real ){
return pMem->u.r;
}else if( pMem->flags & MEM_Int ){
return (double)pMem->u.i;
}else if( pMem->flags & (MEM_Str|MEM_Blob) ){
return memRealValue(pMem);
}else{
/* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
return (double)0;
}
}
/*
** Return 1 if pMem represents true, and return 0 if pMem represents false.
** Return the value ifNull if pMem is NULL.
*/
int sqlite3VdbeBooleanValue(Mem *pMem, int ifNull){
if( pMem->flags & MEM_Int ) return pMem->u.i!=0;
if( pMem->flags & MEM_Null ) return ifNull;
return sqlite3VdbeRealValue(pMem)!=0.0;
}
/*
** The MEM structure is already a MEM_Real. Try to also make it a
** MEM_Int if we can.
*/
void sqlite3VdbeIntegerAffinity(Mem *pMem){
i64 ix;
assert( pMem->flags & MEM_Real );
assert( (pMem->flags & MEM_RowSet)==0 );
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
assert( EIGHT_BYTE_ALIGNMENT(pMem) );
ix = doubleToInt64(pMem->u.r);
/* Only mark the value as an integer if
**
** (1) the round-trip conversion real->int->real is a no-op, and
** (2) The integer is neither the largest nor the smallest
** possible integer (ticket #3922)
**
** The second and third terms in the following conditional enforces
** the second condition under the assumption that addition overflow causes
** values to wrap around.
*/
if( pMem->u.r==ix && ix>SMALLEST_INT64 && ix<LARGEST_INT64 ){
pMem->u.i = ix;
MemSetTypeFlag(pMem, MEM_Int);
}
}
/*
** Convert pMem to type integer. Invalidate any prior representations.
*/
int sqlite3VdbeMemIntegerify(Mem *pMem){
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
assert( (pMem->flags & MEM_RowSet)==0 );
assert( EIGHT_BYTE_ALIGNMENT(pMem) );
pMem->u.i = sqlite3VdbeIntValue(pMem);
MemSetTypeFlag(pMem, MEM_Int);
return SQLITE_OK;
}
/*
** Convert pMem so that it is of type MEM_Real.
** Invalidate any prior representations.
*/
int sqlite3VdbeMemRealify(Mem *pMem){
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
assert( EIGHT_BYTE_ALIGNMENT(pMem) );
pMem->u.r = sqlite3VdbeRealValue(pMem);
MemSetTypeFlag(pMem, MEM_Real);
return SQLITE_OK;
}
/* Compare a floating point value to an integer. Return true if the two
** values are the same within the precision of the floating point value.
**
** For some versions of GCC on 32-bit machines, if you do the more obvious
** comparison of "r1==(double)i" you sometimes get an answer of false even
** though the r1 and (double)i values are bit-for-bit the same.
*/
static int sqlite3RealSameAsInt(double r1, sqlite3_int64 i){
double r2 = (double)i;
return memcmp(&r1, &r2, sizeof(r1))==0;
}
/*
** Convert pMem so that it has types MEM_Real or MEM_Int or both.
** Invalidate any prior representations.
**
** Every effort is made to force the conversion, even if the input
** is a string that does not look completely like a number. Convert
** as much of the string as we can and ignore the rest.
*/
int sqlite3VdbeMemNumerify(Mem *pMem){
if( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))==0 ){
int rc;
assert( (pMem->flags & (MEM_Blob|MEM_Str))!=0 );
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
rc = sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc);
if( rc==0 ){
MemSetTypeFlag(pMem, MEM_Int);
}else{
i64 i = pMem->u.i;
sqlite3AtoF(pMem->z, &pMem->u.r, pMem->n, pMem->enc);
if( rc==1 && sqlite3RealSameAsInt(pMem->u.r, i) ){
pMem->u.i = i;
MemSetTypeFlag(pMem, MEM_Int);
}else{
MemSetTypeFlag(pMem, MEM_Real);
}
}
}
assert( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))!=0 );
pMem->flags &= ~(MEM_Str|MEM_Blob|MEM_Zero);
return SQLITE_OK;
}
/*
** Cast the datatype of the value in pMem according to the affinity
** "aff". Casting is different from applying affinity in that a cast
** is forced. In other words, the value is converted into the desired
** affinity even if that results in loss of data. This routine is
** used (for example) to implement the SQL "cast()" operator.
*/
void sqlite3VdbeMemCast(Mem *pMem, u8 aff, u8 encoding){
if( pMem->flags & MEM_Null ) return;
switch( aff ){
case SQLITE_AFF_BLOB: { /* Really a cast to BLOB */
if( (pMem->flags & MEM_Blob)==0 ){
sqlite3ValueApplyAffinity(pMem, SQLITE_AFF_TEXT, encoding);
assert( pMem->flags & MEM_Str || pMem->db->mallocFailed );
if( pMem->flags & MEM_Str ) MemSetTypeFlag(pMem, MEM_Blob);
}else{
pMem->flags &= ~(MEM_TypeMask&~MEM_Blob);
}
break;
}
case SQLITE_AFF_NUMERIC: {
sqlite3VdbeMemNumerify(pMem);
break;
}
case SQLITE_AFF_INTEGER: {
sqlite3VdbeMemIntegerify(pMem);
break;
}
case SQLITE_AFF_REAL: {
sqlite3VdbeMemRealify(pMem);
break;
}
default: {
assert( aff==SQLITE_AFF_TEXT );
assert( MEM_Str==(MEM_Blob>>3) );
pMem->flags |= (pMem->flags&MEM_Blob)>>3;
sqlite3ValueApplyAffinity(pMem, SQLITE_AFF_TEXT, encoding);
assert( pMem->flags & MEM_Str || pMem->db->mallocFailed );
pMem->flags &= ~(MEM_Int|MEM_Real|MEM_Blob|MEM_Zero);
break;
}
}
}
/*
** Initialize bulk memory to be a consistent Mem object.
**
** The minimum amount of initialization feasible is performed.
*/
void sqlite3VdbeMemInit(Mem *pMem, sqlite3 *db, u16 flags){
assert( (flags & ~MEM_TypeMask)==0 );
pMem->flags = flags;
pMem->db = db;
pMem->szMalloc = 0;
}
/*
** Delete any previous value and set the value stored in *pMem to NULL.
**
** This routine calls the Mem.xDel destructor to dispose of values that
** require the destructor. But it preserves the Mem.zMalloc memory allocation.
** To free all resources, use sqlite3VdbeMemRelease(), which both calls this
** routine to invoke the destructor and deallocates Mem.zMalloc.
**
** Use this routine to reset the Mem prior to insert a new value.
**
** Use sqlite3VdbeMemRelease() to complete erase the Mem prior to abandoning it.
*/
void sqlite3VdbeMemSetNull(Mem *pMem){
if( VdbeMemDynamic(pMem) ){
vdbeMemClearExternAndSetNull(pMem);
}else{
pMem->flags = MEM_Null;
}
}
void sqlite3ValueSetNull(sqlite3_value *p){
sqlite3VdbeMemSetNull((Mem*)p);
}
/*
** Delete any previous value and set the value to be a BLOB of length
** n containing all zeros.
*/
void sqlite3VdbeMemSetZeroBlob(Mem *pMem, int n){
sqlite3VdbeMemRelease(pMem);
pMem->flags = MEM_Blob|MEM_Zero;
pMem->n = 0;
if( n<0 ) n = 0;
pMem->u.nZero = n;
pMem->enc = SQLITE_UTF8;
pMem->z = 0;
}
/*
** The pMem is known to contain content that needs to be destroyed prior
** to a value change. So invoke the destructor, then set the value to
** a 64-bit integer.
*/
static SQLITE_NOINLINE void vdbeReleaseAndSetInt64(Mem *pMem, i64 val){
sqlite3VdbeMemSetNull(pMem);
pMem->u.i = val;
pMem->flags = MEM_Int;
}
/*
** Delete any previous value and set the value stored in *pMem to val,
** manifest type INTEGER.
*/
void sqlite3VdbeMemSetInt64(Mem *pMem, i64 val){
if( VdbeMemDynamic(pMem) ){
vdbeReleaseAndSetInt64(pMem, val);
}else{
pMem->u.i = val;
pMem->flags = MEM_Int;
}
}
/* A no-op destructor */
void sqlite3NoopDestructor(void *p){ UNUSED_PARAMETER(p); }
/*
** Set the value stored in *pMem should already be a NULL.
** Also store a pointer to go with it.
*/
void sqlite3VdbeMemSetPointer(
Mem *pMem,
void *pPtr,
const char *zPType,
void (*xDestructor)(void*)
){
assert( pMem->flags==MEM_Null );
pMem->u.zPType = zPType ? zPType : "";
pMem->z = pPtr;
pMem->flags = MEM_Null|MEM_Dyn|MEM_Subtype|MEM_Term;
pMem->eSubtype = 'p';
pMem->xDel = xDestructor ? xDestructor : sqlite3NoopDestructor;
}
#ifndef SQLITE_OMIT_FLOATING_POINT
/*
** Delete any previous value and set the value stored in *pMem to val,
** manifest type REAL.
*/
void sqlite3VdbeMemSetDouble(Mem *pMem, double val){
sqlite3VdbeMemSetNull(pMem);
if( !sqlite3IsNaN(val) ){
pMem->u.r = val;
pMem->flags = MEM_Real;
}
}
#endif
/*
** Delete any previous value and set the value of pMem to be an
** empty boolean index.
*/
void sqlite3VdbeMemSetRowSet(Mem *pMem){
sqlite3 *db = pMem->db;
assert( db!=0 );
assert( (pMem->flags & MEM_RowSet)==0 );
sqlite3VdbeMemRelease(pMem);
pMem->zMalloc = sqlite3DbMallocRawNN(db, 64);
if( db->mallocFailed ){
pMem->flags = MEM_Null;
pMem->szMalloc = 0;
}else{
assert( pMem->zMalloc );
pMem->szMalloc = sqlite3DbMallocSize(db, pMem->zMalloc);
pMem->u.pRowSet = sqlite3RowSetInit(db, pMem->zMalloc, pMem->szMalloc);
assert( pMem->u.pRowSet!=0 );
pMem->flags = MEM_RowSet;
}
}
/*
** Return true if the Mem object contains a TEXT or BLOB that is
** too large - whose size exceeds SQLITE_MAX_LENGTH.
*/
int sqlite3VdbeMemTooBig(Mem *p){
assert( p->db!=0 );
if( p->flags & (MEM_Str|MEM_Blob) ){
int n = p->n;
if( p->flags & MEM_Zero ){
n += p->u.nZero;
}
return n>p->db->aLimit[SQLITE_LIMIT_LENGTH];
}
return 0;
}
#ifdef SQLITE_DEBUG
/*
** This routine prepares a memory cell for modification by breaking
** its link to a shallow copy and by marking any current shallow
** copies of this cell as invalid.
**
** This is used for testing and debugging only - to make sure shallow
** copies are not misused.
*/
void sqlite3VdbeMemAboutToChange(Vdbe *pVdbe, Mem *pMem){
int i;
Mem *pX;
for(i=0, pX=pVdbe->aMem; i<pVdbe->nMem; i++, pX++){
if( pX->pScopyFrom==pMem ){
pX->flags |= MEM_Undefined;
pX->pScopyFrom = 0;
}
}
pMem->pScopyFrom = 0;
}
#endif /* SQLITE_DEBUG */
/*
** Make an shallow copy of pFrom into pTo. Prior contents of
** pTo are freed. The pFrom->z field is not duplicated. If
** pFrom->z is used, then pTo->z points to the same thing as pFrom->z
** and flags gets srcType (either MEM_Ephem or MEM_Static).
*/
static SQLITE_NOINLINE void vdbeClrCopy(Mem *pTo, const Mem *pFrom, int eType){
vdbeMemClearExternAndSetNull(pTo);
assert( !VdbeMemDynamic(pTo) );
sqlite3VdbeMemShallowCopy(pTo, pFrom, eType);
}
void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){
assert( (pFrom->flags & MEM_RowSet)==0 );
assert( pTo->db==pFrom->db );
if( VdbeMemDynamic(pTo) ){ vdbeClrCopy(pTo,pFrom,srcType); return; }
memcpy(pTo, pFrom, MEMCELLSIZE);
if( (pFrom->flags&MEM_Static)==0 ){
pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Ephem);
assert( srcType==MEM_Ephem || srcType==MEM_Static );
pTo->flags |= srcType;
}
}
/*
** Make a full copy of pFrom into pTo. Prior contents of pTo are
** freed before the copy is made.
*/
int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){
int rc = SQLITE_OK;
assert( (pFrom->flags & MEM_RowSet)==0 );
if( VdbeMemDynamic(pTo) ) vdbeMemClearExternAndSetNull(pTo);
memcpy(pTo, pFrom, MEMCELLSIZE);
pTo->flags &= ~MEM_Dyn;
if( pTo->flags&(MEM_Str|MEM_Blob) ){
if( 0==(pFrom->flags&MEM_Static) ){
pTo->flags |= MEM_Ephem;
rc = sqlite3VdbeMemMakeWriteable(pTo);
}
}
return rc;
}
/*
** Transfer the contents of pFrom to pTo. Any existing value in pTo is
** freed. If pFrom contains ephemeral data, a copy is made.
**
** pFrom contains an SQL NULL when this routine returns.
*/
void sqlite3VdbeMemMove(Mem *pTo, Mem *pFrom){
assert( pFrom->db==0 || sqlite3_mutex_held(pFrom->db->mutex) );
assert( pTo->db==0 || sqlite3_mutex_held(pTo->db->mutex) );
assert( pFrom->db==0 || pTo->db==0 || pFrom->db==pTo->db );
sqlite3VdbeMemRelease(pTo);
memcpy(pTo, pFrom, sizeof(Mem));
pFrom->flags = MEM_Null;
pFrom->szMalloc = 0;
}
/*
** Change the value of a Mem to be a string or a BLOB.
**
** The memory management strategy depends on the value of the xDel
** parameter. If the value passed is SQLITE_TRANSIENT, then the
** string is copied into a (possibly existing) buffer managed by the
** Mem structure. Otherwise, any existing buffer is freed and the
** pointer copied.
**
** If the string is too large (if it exceeds the SQLITE_LIMIT_LENGTH
** size limit) then no memory allocation occurs. If the string can be
** stored without allocating memory, then it is. If a memory allocation
** is required to store the string, then value of pMem is unchanged. In
** either case, SQLITE_TOOBIG is returned.
*/
int sqlite3VdbeMemSetStr(
Mem *pMem, /* Memory cell to set to string value */
const char *z, /* String pointer */
int n, /* Bytes in string, or negative */
u8 enc, /* Encoding of z. 0 for BLOBs */
void (*xDel)(void*) /* Destructor function */
){
int nByte = n; /* New value for pMem->n */
int iLimit; /* Maximum allowed string or blob size */
u16 flags = 0; /* New value for pMem->flags */
assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
assert( (pMem->flags & MEM_RowSet)==0 );
/* If z is a NULL pointer, set pMem to contain an SQL NULL. */
if( !z ){
sqlite3VdbeMemSetNull(pMem);
return SQLITE_OK;
}
if( pMem->db ){
iLimit = pMem->db->aLimit[SQLITE_LIMIT_LENGTH];
}else{
iLimit = SQLITE_MAX_LENGTH;
}
flags = (enc==0?MEM_Blob:MEM_Str);
if( nByte<0 ){
assert( enc!=0 );
if( enc==SQLITE_UTF8 ){
nByte = 0x7fffffff & (int)strlen(z);
if( nByte>iLimit ) nByte = iLimit+1;
}else{
for(nByte=0; nByte<=iLimit && (z[nByte] | z[nByte+1]); nByte+=2){}
}
flags |= MEM_Term;
}
/* The following block sets the new values of Mem.z and Mem.xDel. It
** also sets a flag in local variable "flags" to indicate the memory
** management (one of MEM_Dyn or MEM_Static).
*/
if( xDel==SQLITE_TRANSIENT ){
int nAlloc = nByte;
if( flags&MEM_Term ){
nAlloc += (enc==SQLITE_UTF8?1:2);
}
if( nByte>iLimit ){
return SQLITE_TOOBIG;
}
testcase( nAlloc==0 );
testcase( nAlloc==31 );
testcase( nAlloc==32 );
if( sqlite3VdbeMemClearAndResize(pMem, MAX(nAlloc,32)) ){
return SQLITE_NOMEM_BKPT;
}
memcpy(pMem->z, z, nAlloc);
}else if( xDel==SQLITE_DYNAMIC ){
sqlite3VdbeMemRelease(pMem);
pMem->zMalloc = pMem->z = (char *)z;
pMem->szMalloc = sqlite3DbMallocSize(pMem->db, pMem->zMalloc);
}else{
sqlite3VdbeMemRelease(pMem);
pMem->z = (char *)z;
pMem->xDel = xDel;
flags |= ((xDel==SQLITE_STATIC)?MEM_Static:MEM_Dyn);
}
pMem->n = nByte;
pMem->flags = flags;
pMem->enc = (enc==0 ? SQLITE_UTF8 : enc);
#ifndef SQLITE_OMIT_UTF16
if( pMem->enc!=SQLITE_UTF8 && sqlite3VdbeMemHandleBom(pMem) ){
return SQLITE_NOMEM_BKPT;
}
#endif
if( nByte>iLimit ){
return SQLITE_TOOBIG;
}
return SQLITE_OK;
}
/*
** Move data out of a btree key or data field and into a Mem structure.
** The data is payload from the entry that pCur is currently pointing
** to. offset and amt determine what portion of the data or key to retrieve.
** The result is written into the pMem element.
**
** The pMem object must have been initialized. This routine will use
** pMem->zMalloc to hold the content from the btree, if possible. New
** pMem->zMalloc space will be allocated if necessary. The calling routine
** is responsible for making sure that the pMem object is eventually
** destroyed.
**
** If this routine fails for any reason (malloc returns NULL or unable
** to read from the disk) then the pMem is left in an inconsistent state.
*/
static SQLITE_NOINLINE int vdbeMemFromBtreeResize(
BtCursor *pCur, /* Cursor pointing at record to retrieve. */
u32 offset, /* Offset from the start of data to return bytes from. */
u32 amt, /* Number of bytes to return. */
Mem *pMem /* OUT: Return data in this Mem structure. */
){
int rc;
pMem->flags = MEM_Null;
if( SQLITE_OK==(rc = sqlite3VdbeMemClearAndResize(pMem, amt+1)) ){
rc = sqlite3BtreePayload(pCur, offset, amt, pMem->z);
if( rc==SQLITE_OK ){
pMem->z[amt] = 0; /* Overrun area used when reading malformed records */
pMem->flags = MEM_Blob;
pMem->n = (int)amt;
}else{
sqlite3VdbeMemRelease(pMem);
}
}
return rc;
}
int sqlite3VdbeMemFromBtree(
BtCursor *pCur, /* Cursor pointing at record to retrieve. */
u32 offset, /* Offset from the start of data to return bytes from. */
u32 amt, /* Number of bytes to return. */
Mem *pMem /* OUT: Return data in this Mem structure. */
){
char *zData; /* Data from the btree layer */
u32 available = 0; /* Number of bytes available on the local btree page */
int rc = SQLITE_OK; /* Return code */
assert( sqlite3BtreeCursorIsValid(pCur) );
assert( !VdbeMemDynamic(pMem) );
/* Note: the calls to BtreeKeyFetch() and DataFetch() below assert()
** that both the BtShared and database handle mutexes are held. */
assert( (pMem->flags & MEM_RowSet)==0 );
zData = (char *)sqlite3BtreePayloadFetch(pCur, &available);
assert( zData!=0 );
if( offset+amt<=available ){
pMem->z = &zData[offset];
pMem->flags = MEM_Blob|MEM_Ephem;
pMem->n = (int)amt;
}else{
rc = vdbeMemFromBtreeResize(pCur, offset, amt, pMem);
}
return rc;
}
/*
** The pVal argument is known to be a value other than NULL.
** Convert it into a string with encoding enc and return a pointer
** to a zero-terminated version of that string.
*/
static SQLITE_NOINLINE const void *valueToText(sqlite3_value* pVal, u8 enc){
assert( pVal!=0 );
assert( pVal->db==0 || sqlite3_mutex_held(pVal->db->mutex) );
assert( (enc&3)==(enc&~SQLITE_UTF16_ALIGNED) );
assert( (pVal->flags & MEM_RowSet)==0 );
assert( (pVal->flags & (MEM_Null))==0 );
if( pVal->flags & (MEM_Blob|MEM_Str) ){
if( ExpandBlob(pVal) ) return 0;
pVal->flags |= MEM_Str;
if( pVal->enc != (enc & ~SQLITE_UTF16_ALIGNED) ){
sqlite3VdbeChangeEncoding(pVal, enc & ~SQLITE_UTF16_ALIGNED);
}
if( (enc & SQLITE_UTF16_ALIGNED)!=0 && 1==(1&SQLITE_PTR_TO_INT(pVal->z)) ){
assert( (pVal->flags & (MEM_Ephem|MEM_Static))!=0 );
if( sqlite3VdbeMemMakeWriteable(pVal)!=SQLITE_OK ){
return 0;
}
}
sqlite3VdbeMemNulTerminate(pVal); /* IMP: R-31275-44060 */
}else{
sqlite3VdbeMemStringify(pVal, enc, 0);
assert( 0==(1&SQLITE_PTR_TO_INT(pVal->z)) );
}
assert(pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) || pVal->db==0
|| pVal->db->mallocFailed );
if( pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) ){
assert( sqlite3VdbeMemConsistentDualRep(pVal) );
return pVal->z;
}else{
return 0;
}
}
/* This function is only available internally, it is not part of the
** external API. It works in a similar way to sqlite3_value_text(),
** except the data returned is in the encoding specified by the second
** parameter, which must be one of SQLITE_UTF16BE, SQLITE_UTF16LE or
** SQLITE_UTF8.
**
** (2006-02-16:) The enc value can be or-ed with SQLITE_UTF16_ALIGNED.
** If that is the case, then the result must be aligned on an even byte
** boundary.
*/
const void *sqlite3ValueText(sqlite3_value* pVal, u8 enc){
if( !pVal ) return 0;
assert( pVal->db==0 || sqlite3_mutex_held(pVal->db->mutex) );
assert( (enc&3)==(enc&~SQLITE_UTF16_ALIGNED) );
assert( (pVal->flags & MEM_RowSet)==0 );
if( (pVal->flags&(MEM_Str|MEM_Term))==(MEM_Str|MEM_Term) && pVal->enc==enc ){
assert( sqlite3VdbeMemConsistentDualRep(pVal) );
return pVal->z;
}
if( pVal->flags&MEM_Null ){
return 0;
}
return valueToText(pVal, enc);
}
/*
** Create a new sqlite3_value object.
*/
sqlite3_value *sqlite3ValueNew(sqlite3 *db){
Mem *p = sqlite3DbMallocZero(db, sizeof(*p));
if( p ){
p->flags = MEM_Null;
p->db = db;
}
return p;
}
/*
** Context object passed by sqlite3Stat4ProbeSetValue() through to
** valueNew(). See comments above valueNew() for details.
*/
struct ValueNewStat4Ctx {
Parse *pParse;
Index *pIdx;
UnpackedRecord **ppRec;
int iVal;
};
/*
** Allocate and return a pointer to a new sqlite3_value object. If
** the second argument to this function is NULL, the object is allocated
** by calling sqlite3ValueNew().
**
** Otherwise, if the second argument is non-zero, then this function is
** being called indirectly by sqlite3Stat4ProbeSetValue(). If it has not
** already been allocated, allocate the UnpackedRecord structure that
** that function will return to its caller here. Then return a pointer to
** an sqlite3_value within the UnpackedRecord.a[] array.
*/
static sqlite3_value *valueNew(sqlite3 *db, struct ValueNewStat4Ctx *p){
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
if( p ){
UnpackedRecord *pRec = p->ppRec[0];
if( pRec==0 ){
Index *pIdx = p->pIdx; /* Index being probed */
int nByte; /* Bytes of space to allocate */
int i; /* Counter variable */
int nCol = pIdx->nColumn; /* Number of index columns including rowid */
nByte = sizeof(Mem) * nCol + ROUND8(sizeof(UnpackedRecord));
pRec = (UnpackedRecord*)sqlite3DbMallocZero(db, nByte);
if( pRec ){
pRec->pKeyInfo = sqlite3KeyInfoOfIndex(p->pParse, pIdx);
if( pRec->pKeyInfo ){
assert( pRec->pKeyInfo->nAllField==nCol );
assert( pRec->pKeyInfo->enc==ENC(db) );
pRec->aMem = (Mem *)((u8*)pRec + ROUND8(sizeof(UnpackedRecord)));
for(i=0; i<nCol; i++){
pRec->aMem[i].flags = MEM_Null;
pRec->aMem[i].db = db;
}
}else{
sqlite3DbFreeNN(db, pRec);
pRec = 0;
}
}
if( pRec==0 ) return 0;
p->ppRec[0] = pRec;
}
pRec->nField = p->iVal+1;
return &pRec->aMem[p->iVal];
}
#else
UNUSED_PARAMETER(p);
#endif /* defined(SQLITE_ENABLE_STAT3_OR_STAT4) */
return sqlite3ValueNew(db);
}
/*
** The expression object indicated by the second argument is guaranteed
** to be a scalar SQL function. If
**
** * all function arguments are SQL literals,
** * one of the SQLITE_FUNC_CONSTANT or _SLOCHNG function flags is set, and
** * the SQLITE_FUNC_NEEDCOLL function flag is not set,
**
** then this routine attempts to invoke the SQL function. Assuming no
** error occurs, output parameter (*ppVal) is set to point to a value
** object containing the result before returning SQLITE_OK.
**
** Affinity aff is applied to the result of the function before returning.
** If the result is a text value, the sqlite3_value object uses encoding
** enc.
**
** If the conditions above are not met, this function returns SQLITE_OK
** and sets (*ppVal) to NULL. Or, if an error occurs, (*ppVal) is set to
** NULL and an SQLite error code returned.
*/
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
static int valueFromFunction(
sqlite3 *db, /* The database connection */
Expr *p, /* The expression to evaluate */
u8 enc, /* Encoding to use */
u8 aff, /* Affinity to use */
sqlite3_value **ppVal, /* Write the new value here */
struct ValueNewStat4Ctx *pCtx /* Second argument for valueNew() */
){
sqlite3_context ctx; /* Context object for function invocation */
sqlite3_value **apVal = 0; /* Function arguments */
int nVal = 0; /* Size of apVal[] array */
FuncDef *pFunc = 0; /* Function definition */
sqlite3_value *pVal = 0; /* New value */
int rc = SQLITE_OK; /* Return code */
ExprList *pList = 0; /* Function arguments */
int i; /* Iterator variable */
assert( pCtx!=0 );
assert( (p->flags & EP_TokenOnly)==0 );
pList = p->x.pList;
if( pList ) nVal = pList->nExpr;
pFunc = sqlite3FindFunction(db, p->u.zToken, nVal, enc, 0);
assert( pFunc );
if( (pFunc->funcFlags & (SQLITE_FUNC_CONSTANT|SQLITE_FUNC_SLOCHNG))==0
|| (pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL)
){
return SQLITE_OK;
}
if( pList ){
apVal = (sqlite3_value**)sqlite3DbMallocZero(db, sizeof(apVal[0]) * nVal);
if( apVal==0 ){
rc = SQLITE_NOMEM_BKPT;
goto value_from_function_out;
}
for(i=0; i<nVal; i++){
rc = sqlite3ValueFromExpr(db, pList->a[i].pExpr, enc, aff, &apVal[i]);
if( apVal[i]==0 || rc!=SQLITE_OK ) goto value_from_function_out;
}
}
pVal = valueNew(db, pCtx);
if( pVal==0 ){
rc = SQLITE_NOMEM_BKPT;
goto value_from_function_out;
}
assert( pCtx->pParse->rc==SQLITE_OK );
memset(&ctx, 0, sizeof(ctx));
ctx.pOut = pVal;
ctx.pFunc = pFunc;
pFunc->xSFunc(&ctx, nVal, apVal);
if( ctx.isError ){
rc = ctx.isError;
sqlite3ErrorMsg(pCtx->pParse, "%s", sqlite3_value_text(pVal));
}else{
sqlite3ValueApplyAffinity(pVal, aff, SQLITE_UTF8);
assert( rc==SQLITE_OK );
rc = sqlite3VdbeChangeEncoding(pVal, enc);
if( rc==SQLITE_OK && sqlite3VdbeMemTooBig(pVal) ){
rc = SQLITE_TOOBIG;
pCtx->pParse->nErr++;
}
}
pCtx->pParse->rc = rc;
value_from_function_out:
if( rc!=SQLITE_OK ){
pVal = 0;
}
if( apVal ){
for(i=0; i<nVal; i++){
sqlite3ValueFree(apVal[i]);
}
sqlite3DbFreeNN(db, apVal);
}
*ppVal = pVal;
return rc;
}
#else
# define valueFromFunction(a,b,c,d,e,f) SQLITE_OK
#endif /* defined(SQLITE_ENABLE_STAT3_OR_STAT4) */
/*
** Extract a value from the supplied expression in the manner described
** above sqlite3ValueFromExpr(). Allocate the sqlite3_value object
** using valueNew().
**
** If pCtx is NULL and an error occurs after the sqlite3_value object
** has been allocated, it is freed before returning. Or, if pCtx is not
** NULL, it is assumed that the caller will free any allocated object
** in all cases.
*/
static int valueFromExpr(
sqlite3 *db, /* The database connection */
Expr *pExpr, /* The expression to evaluate */
u8 enc, /* Encoding to use */
u8 affinity, /* Affinity to use */
sqlite3_value **ppVal, /* Write the new value here */
struct ValueNewStat4Ctx *pCtx /* Second argument for valueNew() */
){
int op;
char *zVal = 0;
sqlite3_value *pVal = 0;
int negInt = 1;
const char *zNeg = "";
int rc = SQLITE_OK;
assert( pExpr!=0 );
while( (op = pExpr->op)==TK_UPLUS || op==TK_SPAN ) pExpr = pExpr->pLeft;
#if defined(SQLITE_ENABLE_STAT3_OR_STAT4)
if( op==TK_REGISTER ) op = pExpr->op2;
#else
if( NEVER(op==TK_REGISTER) ) op = pExpr->op2;
#endif
/* Compressed expressions only appear when parsing the DEFAULT clause
** on a table column definition, and hence only when pCtx==0. This
** check ensures that an EP_TokenOnly expression is never passed down
** into valueFromFunction(). */
assert( (pExpr->flags & EP_TokenOnly)==0 || pCtx==0 );
if( op==TK_CAST ){
u8 aff = sqlite3AffinityType(pExpr->u.zToken,0);
rc = valueFromExpr(db, pExpr->pLeft, enc, aff, ppVal, pCtx);
testcase( rc!=SQLITE_OK );
if( *ppVal ){
sqlite3VdbeMemCast(*ppVal, aff, SQLITE_UTF8);
sqlite3ValueApplyAffinity(*ppVal, affinity, SQLITE_UTF8);
}
return rc;
}
/* Handle negative integers in a single step. This is needed in the
** case when the value is -9223372036854775808.
*/
if( op==TK_UMINUS
&& (pExpr->pLeft->op==TK_INTEGER || pExpr->pLeft->op==TK_FLOAT) ){
pExpr = pExpr->pLeft;
op = pExpr->op;
negInt = -1;
zNeg = "-";
}
if( op==TK_STRING || op==TK_FLOAT || op==TK_INTEGER ){
pVal = valueNew(db, pCtx);
if( pVal==0 ) goto no_mem;
if( ExprHasProperty(pExpr, EP_IntValue) ){
sqlite3VdbeMemSetInt64(pVal, (i64)pExpr->u.iValue*negInt);
}else{
zVal = sqlite3MPrintf(db, "%s%s", zNeg, pExpr->u.zToken);
if( zVal==0 ) goto no_mem;
sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, SQLITE_DYNAMIC);
}
if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_BLOB ){
sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, SQLITE_UTF8);
}else{
sqlite3ValueApplyAffinity(pVal, affinity, SQLITE_UTF8);
}
if( pVal->flags & (MEM_Int|MEM_Real) ) pVal->flags &= ~MEM_Str;
if( enc!=SQLITE_UTF8 ){
rc = sqlite3VdbeChangeEncoding(pVal, enc);
}
}else if( op==TK_UMINUS ) {
/* This branch happens for multiple negative signs. Ex: -(-5) */
if( SQLITE_OK==valueFromExpr(db,pExpr->pLeft,enc,affinity,&pVal,pCtx)
&& pVal!=0
){
sqlite3VdbeMemNumerify(pVal);
if( pVal->flags & MEM_Real ){
pVal->u.r = -pVal->u.r;
}else if( pVal->u.i==SMALLEST_INT64 ){
pVal->u.r = -(double)SMALLEST_INT64;
MemSetTypeFlag(pVal, MEM_Real);
}else{
pVal->u.i = -pVal->u.i;
}
sqlite3ValueApplyAffinity(pVal, affinity, enc);
}
}else if( op==TK_NULL ){
pVal = valueNew(db, pCtx);
if( pVal==0 ) goto no_mem;
sqlite3VdbeMemNumerify(pVal);
}
#ifndef SQLITE_OMIT_BLOB_LITERAL
else if( op==TK_BLOB ){
int nVal;
assert( pExpr->u.zToken[0]=='x' || pExpr->u.zToken[0]=='X' );
assert( pExpr->u.zToken[1]=='\'' );
pVal = valueNew(db, pCtx);
if( !pVal ) goto no_mem;
zVal = &pExpr->u.zToken[2];
nVal = sqlite3Strlen30(zVal)-1;
assert( zVal[nVal]=='\'' );
sqlite3VdbeMemSetStr(pVal, sqlite3HexToBlob(db, zVal, nVal), nVal/2,
0, SQLITE_DYNAMIC);
}
#endif
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
else if( op==TK_FUNCTION && pCtx!=0 ){
rc = valueFromFunction(db, pExpr, enc, affinity, &pVal, pCtx);
}
#endif
else if( op==TK_TRUEFALSE ){
pVal = valueNew(db, pCtx);
pVal->flags = MEM_Int;
pVal->u.i = pExpr->u.zToken[4]==0;
}
*ppVal = pVal;
return rc;
no_mem:
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
if( pCtx==0 || pCtx->pParse->nErr==0 )
#endif
sqlite3OomFault(db);
sqlite3DbFree(db, zVal);
assert( *ppVal==0 );
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
if( pCtx==0 ) sqlite3ValueFree(pVal);
#else
assert( pCtx==0 ); sqlite3ValueFree(pVal);
#endif
return SQLITE_NOMEM_BKPT;
}
/*
** Create a new sqlite3_value object, containing the value of pExpr.
**
** This only works for very simple expressions that consist of one constant
** token (i.e. "5", "5.1", "'a string'"). If the expression can
** be converted directly into a value, then the value is allocated and
** a pointer written to *ppVal. The caller is responsible for deallocating
** the value by passing it to sqlite3ValueFree() later on. If the expression
** cannot be converted to a value, then *ppVal is set to NULL.
*/
int sqlite3ValueFromExpr(
sqlite3 *db, /* The database connection */
Expr *pExpr, /* The expression to evaluate */
u8 enc, /* Encoding to use */
u8 affinity, /* Affinity to use */
sqlite3_value **ppVal /* Write the new value here */
){
return pExpr ? valueFromExpr(db, pExpr, enc, affinity, ppVal, 0) : 0;
}
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
/*
** The implementation of the sqlite_record() function. This function accepts
** a single argument of any type. The return value is a formatted database
** record (a blob) containing the argument value.
**
** This is used to convert the value stored in the 'sample' column of the
** sqlite_stat3 table to the record format SQLite uses internally.
*/
static void recordFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
const int file_format = 1;
u32 iSerial; /* Serial type */
int nSerial; /* Bytes of space for iSerial as varint */
u32 nVal; /* Bytes of space required for argv[0] */
int nRet;
sqlite3 *db;
u8 *aRet;
UNUSED_PARAMETER( argc );
iSerial = sqlite3VdbeSerialType(argv[0], file_format, &nVal);
nSerial = sqlite3VarintLen(iSerial);
db = sqlite3_context_db_handle(context);
nRet = 1 + nSerial + nVal;
aRet = sqlite3DbMallocRawNN(db, nRet);
if( aRet==0 ){
sqlite3_result_error_nomem(context);
}else{
aRet[0] = nSerial+1;
putVarint32(&aRet[1], iSerial);
sqlite3VdbeSerialPut(&aRet[1+nSerial], argv[0], iSerial);
sqlite3_result_blob(context, aRet, nRet, SQLITE_TRANSIENT);
sqlite3DbFreeNN(db, aRet);
}
}
/*
** Register built-in functions used to help read ANALYZE data.
*/
void sqlite3AnalyzeFunctions(void){
static FuncDef aAnalyzeTableFuncs[] = {
FUNCTION(sqlite_record, 1, 0, 0, recordFunc),
};
sqlite3InsertBuiltinFuncs(aAnalyzeTableFuncs, ArraySize(aAnalyzeTableFuncs));
}
/*
** Attempt to extract a value from pExpr and use it to construct *ppVal.
**
** If pAlloc is not NULL, then an UnpackedRecord object is created for
** pAlloc if one does not exist and the new value is added to the
** UnpackedRecord object.
**
** A value is extracted in the following cases:
**
** * (pExpr==0). In this case the value is assumed to be an SQL NULL,
**
** * The expression is a bound variable, and this is a reprepare, or
**
** * The expression is a literal value.
**
** On success, *ppVal is made to point to the extracted value. The caller
** is responsible for ensuring that the value is eventually freed.
*/
static int stat4ValueFromExpr(
Parse *pParse, /* Parse context */
Expr *pExpr, /* The expression to extract a value from */
u8 affinity, /* Affinity to use */
struct ValueNewStat4Ctx *pAlloc,/* How to allocate space. Or NULL */
sqlite3_value **ppVal /* OUT: New value object (or NULL) */
){
int rc = SQLITE_OK;
sqlite3_value *pVal = 0;
sqlite3 *db = pParse->db;
/* Skip over any TK_COLLATE nodes */
pExpr = sqlite3ExprSkipCollate(pExpr);
assert( pExpr==0 || pExpr->op!=TK_REGISTER || pExpr->op2!=TK_VARIABLE );
if( !pExpr ){
pVal = valueNew(db, pAlloc);
if( pVal ){
sqlite3VdbeMemSetNull((Mem*)pVal);
}
}else if( pExpr->op==TK_VARIABLE && (db->flags & SQLITE_EnableQPSG)==0 ){
Vdbe *v;
int iBindVar = pExpr->iColumn;
sqlite3VdbeSetVarmask(pParse->pVdbe, iBindVar);
if( (v = pParse->pReprepare)!=0 ){
pVal = valueNew(db, pAlloc);
if( pVal ){
rc = sqlite3VdbeMemCopy((Mem*)pVal, &v->aVar[iBindVar-1]);
sqlite3ValueApplyAffinity(pVal, affinity, ENC(db));
pVal->db = pParse->db;
}
}
}else{
rc = valueFromExpr(db, pExpr, ENC(db), affinity, &pVal, pAlloc);
}
assert( pVal==0 || pVal->db==db );
*ppVal = pVal;
return rc;
}
/*
** This function is used to allocate and populate UnpackedRecord
** structures intended to be compared against sample index keys stored
** in the sqlite_stat4 table.
**
** A single call to this function populates zero or more fields of the
** record starting with field iVal (fields are numbered from left to
** right starting with 0). A single field is populated if:
**
** * (pExpr==0). In this case the value is assumed to be an SQL NULL,
**
** * The expression is a bound variable, and this is a reprepare, or
**
** * The sqlite3ValueFromExpr() function is able to extract a value
** from the expression (i.e. the expression is a literal value).
**
** Or, if pExpr is a TK_VECTOR, one field is populated for each of the
** vector components that match either of the two latter criteria listed
** above.
**
** Before any value is appended to the record, the affinity of the
** corresponding column within index pIdx is applied to it. Before
** this function returns, output parameter *pnExtract is set to the
** number of values appended to the record.
**
** When this function is called, *ppRec must either point to an object
** allocated by an earlier call to this function, or must be NULL. If it
** is NULL and a value can be successfully extracted, a new UnpackedRecord
** is allocated (and *ppRec set to point to it) before returning.
**
** Unless an error is encountered, SQLITE_OK is returned. It is not an
** error if a value cannot be extracted from pExpr. If an error does
** occur, an SQLite error code is returned.
*/
int sqlite3Stat4ProbeSetValue(
Parse *pParse, /* Parse context */
Index *pIdx, /* Index being probed */
UnpackedRecord **ppRec, /* IN/OUT: Probe record */
Expr *pExpr, /* The expression to extract a value from */
int nElem, /* Maximum number of values to append */
int iVal, /* Array element to populate */
int *pnExtract /* OUT: Values appended to the record */
){
int rc = SQLITE_OK;
int nExtract = 0;
if( pExpr==0 || pExpr->op!=TK_SELECT ){
int i;
struct ValueNewStat4Ctx alloc;
alloc.pParse = pParse;
alloc.pIdx = pIdx;
alloc.ppRec = ppRec;
for(i=0; i<nElem; i++){
sqlite3_value *pVal = 0;
Expr *pElem = (pExpr ? sqlite3VectorFieldSubexpr(pExpr, i) : 0);
u8 aff = sqlite3IndexColumnAffinity(pParse->db, pIdx, iVal+i);
alloc.iVal = iVal+i;
rc = stat4ValueFromExpr(pParse, pElem, aff, &alloc, &pVal);
if( !pVal ) break;
nExtract++;
}
}
*pnExtract = nExtract;
return rc;
}
/*
** Attempt to extract a value from expression pExpr using the methods
** as described for sqlite3Stat4ProbeSetValue() above.
**
** If successful, set *ppVal to point to a new value object and return
** SQLITE_OK. If no value can be extracted, but no other error occurs
** (e.g. OOM), return SQLITE_OK and set *ppVal to NULL. Or, if an error
** does occur, return an SQLite error code. The final value of *ppVal
** is undefined in this case.
*/
int sqlite3Stat4ValueFromExpr(
Parse *pParse, /* Parse context */
Expr *pExpr, /* The expression to extract a value from */
u8 affinity, /* Affinity to use */
sqlite3_value **ppVal /* OUT: New value object (or NULL) */
){
return stat4ValueFromExpr(pParse, pExpr, affinity, 0, ppVal);
}
/*
** Extract the iCol-th column from the nRec-byte record in pRec. Write
** the column value into *ppVal. If *ppVal is initially NULL then a new
** sqlite3_value object is allocated.
**
** If *ppVal is initially NULL then the caller is responsible for
** ensuring that the value written into *ppVal is eventually freed.
*/
int sqlite3Stat4Column(
sqlite3 *db, /* Database handle */
const void *pRec, /* Pointer to buffer containing record */
int nRec, /* Size of buffer pRec in bytes */
int iCol, /* Column to extract */
sqlite3_value **ppVal /* OUT: Extracted value */
){
u32 t; /* a column type code */
int nHdr; /* Size of the header in the record */
int iHdr; /* Next unread header byte */
int iField; /* Next unread data byte */
int szField; /* Size of the current data field */
int i; /* Column index */
u8 *a = (u8*)pRec; /* Typecast byte array */
Mem *pMem = *ppVal; /* Write result into this Mem object */
assert( iCol>0 );
iHdr = getVarint32(a, nHdr);
if( nHdr>nRec || iHdr>=nHdr ) return SQLITE_CORRUPT_BKPT;
iField = nHdr;
for(i=0; i<=iCol; i++){
iHdr += getVarint32(&a[iHdr], t);
testcase( iHdr==nHdr );
testcase( iHdr==nHdr+1 );
if( iHdr>nHdr ) return SQLITE_CORRUPT_BKPT;
szField = sqlite3VdbeSerialTypeLen(t);
iField += szField;
}
testcase( iField==nRec );
testcase( iField==nRec+1 );
if( iField>nRec ) return SQLITE_CORRUPT_BKPT;
if( pMem==0 ){
pMem = *ppVal = sqlite3ValueNew(db);
if( pMem==0 ) return SQLITE_NOMEM_BKPT;
}
sqlite3VdbeSerialGet(&a[iField-szField], t, pMem);
pMem->enc = ENC(db);
return SQLITE_OK;
}
/*
** Unless it is NULL, the argument must be an UnpackedRecord object returned
** by an earlier call to sqlite3Stat4ProbeSetValue(). This call deletes
** the object.
*/
void sqlite3Stat4ProbeFree(UnpackedRecord *pRec){
if( pRec ){
int i;
int nCol = pRec->pKeyInfo->nAllField;
Mem *aMem = pRec->aMem;
sqlite3 *db = aMem[0].db;
for(i=0; i<nCol; i++){
sqlite3VdbeMemRelease(&aMem[i]);
}
sqlite3KeyInfoUnref(pRec->pKeyInfo);
sqlite3DbFreeNN(db, pRec);
}
}
#endif /* ifdef SQLITE_ENABLE_STAT4 */
/*
** Change the string value of an sqlite3_value object
*/
void sqlite3ValueSetStr(
sqlite3_value *v, /* Value to be set */
int n, /* Length of string z */
const void *z, /* Text of the new string */
u8 enc, /* Encoding to use */
void (*xDel)(void*) /* Destructor for the string */
){
if( v ) sqlite3VdbeMemSetStr((Mem *)v, z, n, enc, xDel);
}
/*
** Free an sqlite3_value object
*/
void sqlite3ValueFree(sqlite3_value *v){
if( !v ) return;
sqlite3VdbeMemRelease((Mem *)v);
sqlite3DbFreeNN(((Mem*)v)->db, v);
}
/*
** The sqlite3ValueBytes() routine returns the number of bytes in the
** sqlite3_value object assuming that it uses the encoding "enc".
** The valueBytes() routine is a helper function.
*/
static SQLITE_NOINLINE int valueBytes(sqlite3_value *pVal, u8 enc){
return valueToText(pVal, enc)!=0 ? pVal->n : 0;
}
int sqlite3ValueBytes(sqlite3_value *pVal, u8 enc){
Mem *p = (Mem*)pVal;
assert( (p->flags & MEM_Null)==0 || (p->flags & (MEM_Str|MEM_Blob))==0 );
if( (p->flags & MEM_Str)!=0 && pVal->enc==enc ){
return p->n;
}
if( (p->flags & MEM_Blob)!=0 ){
if( p->flags & MEM_Zero ){
return p->n + p->u.nZero;
}else{
return p->n;
}
}
if( p->flags & MEM_Null ) return 0;
return valueBytes(pVal, enc);
}
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