diff options
Diffstat (limited to 'kexi/3rdparty/kexisql3/src/vdbemem.c')
| -rw-r--r-- | kexi/3rdparty/kexisql3/src/vdbemem.c | 840 |
1 files changed, 840 insertions, 0 deletions
diff --git a/kexi/3rdparty/kexisql3/src/vdbemem.c b/kexi/3rdparty/kexisql3/src/vdbemem.c new file mode 100644 index 00000000..0b7e193b --- /dev/null +++ b/kexi/3rdparty/kexisql3/src/vdbemem.c @@ -0,0 +1,840 @@ +/* +** 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 "os.h" +#include <ctype.h> +#include "vdbeInt.h" + +/* +** 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){ + int rc; + if( !(pMem->flags&MEM_Str) || pMem->enc==desiredEnc ){ + return SQLITE_OK; + } +#ifdef SQLITE_OMIT_UTF16 + return SQLITE_ERROR; +#else + rc = sqlite3VdbeMemTranslate(pMem, desiredEnc); + if( rc==SQLITE_NOMEM ){ + sqlite3VdbeMemRelease(pMem); + pMem->flags = MEM_Null; + pMem->z = 0; + } + return rc; +#endif +} + +/* +** Make the given Mem object MEM_Dyn. +** +** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails. +*/ +int sqlite3VdbeMemDynamicify(Mem *pMem){ + int n = pMem->n; + u8 *z; + if( (pMem->flags & (MEM_Ephem|MEM_Static|MEM_Short))==0 ){ + return SQLITE_OK; + } + assert( (pMem->flags & MEM_Dyn)==0 ); + assert( pMem->flags & (MEM_Str|MEM_Blob) ); + z = sqliteMallocRaw( n+2 ); + if( z==0 ){ + return SQLITE_NOMEM; + } + pMem->flags |= MEM_Dyn|MEM_Term; + pMem->xDel = 0; + memcpy(z, pMem->z, n ); + z[n] = 0; + z[n+1] = 0; + pMem->z = z; + pMem->flags &= ~(MEM_Ephem|MEM_Static|MEM_Short); + return SQLITE_OK; +} + +/* +** Make the given Mem object either MEM_Short or MEM_Dyn so that bytes +** of the Mem.z[] array can be modified. +** +** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails. +*/ +int sqlite3VdbeMemMakeWriteable(Mem *pMem){ + int n; + u8 *z; + if( (pMem->flags & (MEM_Ephem|MEM_Static))==0 ){ + return SQLITE_OK; + } + assert( (pMem->flags & MEM_Dyn)==0 ); + assert( pMem->flags & (MEM_Str|MEM_Blob) ); + if( (n = pMem->n)+2<sizeof(pMem->zShort) ){ + z = pMem->zShort; + pMem->flags |= MEM_Short|MEM_Term; + }else{ + z = sqliteMallocRaw( n+2 ); + if( z==0 ){ + return SQLITE_NOMEM; + } + pMem->flags |= MEM_Dyn|MEM_Term; + pMem->xDel = 0; + } + memcpy(z, pMem->z, n ); + z[n] = 0; + z[n+1] = 0; + pMem->z = z; + pMem->flags &= ~(MEM_Ephem|MEM_Static); + return SQLITE_OK; +} + +/* +** Make sure the given Mem is \u0000 terminated. +*/ +int sqlite3VdbeMemNulTerminate(Mem *pMem){ + /* In SQLite, a string without a nul terminator occurs when a string + ** is loaded from disk (in this case the memory management is ephemeral), + ** or when it is supplied by the user as a bound variable or function + ** return value. Therefore, the memory management of the string must be + ** either ephemeral, static or controlled by a user-supplied destructor. + */ + assert( + !(pMem->flags&MEM_Str) || /* it's not a string, or */ + (pMem->flags&MEM_Term) || /* it's nul term. already, or */ + (pMem->flags&(MEM_Ephem|MEM_Static)) || /* it's static or ephem, or */ + (pMem->flags&MEM_Dyn && pMem->xDel) /* external management */ + ); + if( (pMem->flags & MEM_Term)!=0 || (pMem->flags & MEM_Str)==0 ){ + return SQLITE_OK; /* Nothing to do */ + } + + if( pMem->flags & (MEM_Static|MEM_Ephem) ){ + return sqlite3VdbeMemMakeWriteable(pMem); + }else{ + char *z = sqliteMalloc(pMem->n+2); + if( !z ) return SQLITE_NOMEM; + memcpy(z, pMem->z, pMem->n); + z[pMem->n] = 0; + z[pMem->n+1] = 0; + pMem->xDel(pMem->z); + pMem->xDel = 0; + pMem->z = z; + } + return SQLITE_OK; +} + +/* +** 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 *not* invalidated. +** +** 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 later is an internal programming error. +*/ +int sqlite3VdbeMemStringify(Mem *pMem, int enc){ + int rc = SQLITE_OK; + int fg = pMem->flags; + u8 *z = pMem->zShort; + + assert( !(fg&(MEM_Str|MEM_Blob)) ); + assert( fg&(MEM_Int|MEM_Real) ); + + /* 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_Real ){ + sqlite3_snprintf(NBFS, z, "%!.15g", pMem->r); + }else{ + assert( fg & MEM_Int ); + sqlite3_snprintf(NBFS, z, "%lld", pMem->i); + } + pMem->n = strlen(z); + pMem->z = z; + pMem->enc = SQLITE_UTF8; + pMem->flags |= MEM_Str | MEM_Short | MEM_Term; + sqlite3VdbeChangeEncoding(pMem, enc); + return rc; +} + +/* +** 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. +*/ +void sqlite3VdbeMemFinalize(Mem *pMem, FuncDef *pFunc){ + if( pFunc && pFunc->xFinalize ){ + sqlite3_context ctx; + assert( (pMem->flags & MEM_Null)!=0 || pFunc==*(FuncDef**)&pMem->i ); + ctx.s.flags = MEM_Null; + ctx.s.z = pMem->zShort; + ctx.pMem = pMem; + ctx.pFunc = pFunc; + pFunc->xFinalize(&ctx); + if( pMem->z && pMem->z!=pMem->zShort ){ + sqliteFree( pMem->z ); + } + *pMem = ctx.s; + if( pMem->flags & MEM_Short ){ + pMem->z = pMem->zShort; + } + } +} + +/* +** Release any memory held by the Mem. This may leave the Mem in an +** inconsistent state, for example with (Mem.z==0) and +** (Mem.type==SQLITE_TEXT). +*/ +void sqlite3VdbeMemRelease(Mem *p){ + if( p->flags & (MEM_Dyn|MEM_Agg) ){ + if( p->xDel ){ + if( p->flags & MEM_Agg ){ + sqlite3VdbeMemFinalize(p, *(FuncDef**)&p->i); + assert( (p->flags & MEM_Agg)==0 ); + sqlite3VdbeMemRelease(p); + }else{ + p->xDel((void *)p->z); + } + }else{ + sqliteFree(p->z); + } + p->z = 0; + p->xDel = 0; + } +} + +/* +** 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 a integer and return that. If pMem is NULL, return 0. +** +** If pMem is a string, its encoding might be changed. +*/ +i64 sqlite3VdbeIntValue(Mem *pMem){ + int flags = pMem->flags; + if( flags & MEM_Int ){ + return pMem->i; + }else if( flags & MEM_Real ){ + return (i64)pMem->r; + }else if( flags & (MEM_Str|MEM_Blob) ){ + i64 value; + if( sqlite3VdbeChangeEncoding(pMem, SQLITE_UTF8) + || sqlite3VdbeMemNulTerminate(pMem) ){ + return SQLITE_NOMEM; + } + assert( pMem->z ); + sqlite3atoi64(pMem->z, &value); + return value; + }else{ + return 0; + } +} + +/* +** Convert pMem to type integer. Invalidate any prior representations. +*/ +int sqlite3VdbeMemIntegerify(Mem *pMem){ + pMem->i = sqlite3VdbeIntValue(pMem); + sqlite3VdbeMemRelease(pMem); + pMem->flags = MEM_Int; + return SQLITE_OK; +} + +/* +** 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. +*/ +double sqlite3VdbeRealValue(Mem *pMem){ + if( pMem->flags & MEM_Real ){ + return pMem->r; + }else if( pMem->flags & MEM_Int ){ + return (double)pMem->i; + }else if( pMem->flags & (MEM_Str|MEM_Blob) ){ + double val = 0.0; + if( sqlite3VdbeChangeEncoding(pMem, SQLITE_UTF8) + || sqlite3VdbeMemNulTerminate(pMem) ){ + return SQLITE_NOMEM; + } + assert( pMem->z ); + sqlite3AtoF(pMem->z, &val); + return val; + }else{ + return 0.0; + } +} + +/* +** Convert pMem so that it is of type MEM_Real. Invalidate any +** prior representations. +*/ +int sqlite3VdbeMemRealify(Mem *pMem){ + pMem->r = sqlite3VdbeRealValue(pMem); + sqlite3VdbeMemRelease(pMem); + pMem->flags = MEM_Real; + return SQLITE_OK; +} + +/* +** Delete any previous value and set the value stored in *pMem to NULL. +*/ +void sqlite3VdbeMemSetNull(Mem *pMem){ + sqlite3VdbeMemRelease(pMem); + pMem->flags = MEM_Null; + pMem->type = SQLITE_NULL; + pMem->n = 0; +} + +/* +** Delete any previous value and set the value stored in *pMem to val, +** manifest type INTEGER. +*/ +void sqlite3VdbeMemSetInt64(Mem *pMem, i64 val){ + sqlite3VdbeMemRelease(pMem); + pMem->i = val; + pMem->flags = MEM_Int; + pMem->type = SQLITE_INTEGER; +} + +/* +** Delete any previous value and set the value stored in *pMem to val, +** manifest type REAL. +*/ +void sqlite3VdbeMemSetDouble(Mem *pMem, double val){ + sqlite3VdbeMemRelease(pMem); + pMem->r = val; + pMem->flags = MEM_Real; + pMem->type = SQLITE_FLOAT; +} + +/* +** Make an shallow copy of pFrom into pTo. Prior contents of +** pTo are overwritten. 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). +*/ +void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){ + memcpy(pTo, pFrom, sizeof(*pFrom)-sizeof(pFrom->zShort)); + pTo->xDel = 0; + if( pTo->flags & (MEM_Str|MEM_Blob) ){ + pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Short|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; + if( pTo->flags & MEM_Dyn ){ + sqlite3VdbeMemRelease(pTo); + } + sqlite3VdbeMemShallowCopy(pTo, pFrom, MEM_Ephem); + if( pTo->flags & MEM_Ephem ){ + rc = sqlite3VdbeMemMakeWriteable(pTo); + }else{ + rc = SQLITE_OK; + } + 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. SQLITE_NOMEM +** might be returned if pFrom held ephemeral data and we were unable +** to allocate enough space to make a copy. +*/ +int sqlite3VdbeMemMove(Mem *pTo, Mem *pFrom){ + int rc; + if( pTo->flags & MEM_Dyn ){ + sqlite3VdbeMemRelease(pTo); + } + memcpy(pTo, pFrom, sizeof(Mem)); + if( pFrom->flags & MEM_Short ){ + pTo->z = pTo->zShort; + } + pFrom->flags = MEM_Null; + pFrom->xDel = 0; + if( pTo->flags & MEM_Ephem ){ + rc = sqlite3VdbeMemMakeWriteable(pTo); + }else{ + rc = SQLITE_OK; + } + return rc; +} + +/* +** Change the value of a Mem to be a string or a BLOB. +*/ +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 */ +){ + sqlite3VdbeMemRelease(pMem); + if( !z ){ + pMem->flags = MEM_Null; + pMem->type = SQLITE_NULL; + return SQLITE_OK; + } + + pMem->z = (char *)z; + if( xDel==SQLITE_STATIC ){ + pMem->flags = MEM_Static; + }else if( xDel==SQLITE_TRANSIENT ){ + pMem->flags = MEM_Ephem; + }else{ + pMem->flags = MEM_Dyn; + pMem->xDel = xDel; + } + + pMem->enc = enc; + pMem->type = enc==0 ? SQLITE_BLOB : SQLITE_TEXT; + pMem->n = n; + + assert( enc==0 || enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE + || enc==SQLITE_UTF16BE ); + switch( enc ){ + case 0: + pMem->flags |= MEM_Blob; + pMem->enc = SQLITE_UTF8; + break; + + case SQLITE_UTF8: + pMem->flags |= MEM_Str; + if( n<0 ){ + pMem->n = strlen(z); + pMem->flags |= MEM_Term; + } + break; + +#ifndef SQLITE_OMIT_UTF16 + case SQLITE_UTF16LE: + case SQLITE_UTF16BE: + pMem->flags |= MEM_Str; + if( pMem->n<0 ){ + pMem->n = sqlite3utf16ByteLen(pMem->z,-1); + pMem->flags |= MEM_Term; + } + if( sqlite3VdbeMemHandleBom(pMem) ){ + return SQLITE_NOMEM; + } +#endif /* SQLITE_OMIT_UTF16 */ + } + if( pMem->flags&MEM_Ephem ){ + return sqlite3VdbeMemMakeWriteable(pMem); + } + return SQLITE_OK; +} + +/* +** Compare the values contained by the two memory cells, returning +** negative, zero or positive if pMem1 is less than, equal to, or greater +** than pMem2. Sorting order is NULL's first, followed by numbers (integers +** and reals) sorted numerically, followed by text ordered by the collating +** sequence pColl and finally blob's ordered by memcmp(). +** +** Two NULL values are considered equal by this function. +*/ +int sqlite3MemCompare(const Mem *pMem1, const Mem *pMem2, const CollSeq *pColl){ + int rc; + int f1, f2; + int combined_flags; + + /* Interchange pMem1 and pMem2 if the collating sequence specifies + ** DESC order. + */ + f1 = pMem1->flags; + f2 = pMem2->flags; + combined_flags = f1|f2; + + /* If one value is NULL, it is less than the other. If both values + ** are NULL, return 0. + */ + if( combined_flags&MEM_Null ){ + return (f2&MEM_Null) - (f1&MEM_Null); + } + + /* If one value is a number and the other is not, the number is less. + ** If both are numbers, compare as reals if one is a real, or as integers + ** if both values are integers. + */ + if( combined_flags&(MEM_Int|MEM_Real) ){ + if( !(f1&(MEM_Int|MEM_Real)) ){ + return 1; + } + if( !(f2&(MEM_Int|MEM_Real)) ){ + return -1; + } + if( (f1 & f2 & MEM_Int)==0 ){ + double r1, r2; + if( (f1&MEM_Real)==0 ){ + r1 = pMem1->i; + }else{ + r1 = pMem1->r; + } + if( (f2&MEM_Real)==0 ){ + r2 = pMem2->i; + }else{ + r2 = pMem2->r; + } + if( r1<r2 ) return -1; + if( r1>r2 ) return 1; + return 0; + }else{ + assert( f1&MEM_Int ); + assert( f2&MEM_Int ); + if( pMem1->i < pMem2->i ) return -1; + if( pMem1->i > pMem2->i ) return 1; + return 0; + } + } + + /* If one value is a string and the other is a blob, the string is less. + ** If both are strings, compare using the collating functions. + */ + if( combined_flags&MEM_Str ){ + if( (f1 & MEM_Str)==0 ){ + return 1; + } + if( (f2 & MEM_Str)==0 ){ + return -1; + } + + assert( pMem1->enc==pMem2->enc ); + assert( pMem1->enc==SQLITE_UTF8 || + pMem1->enc==SQLITE_UTF16LE || pMem1->enc==SQLITE_UTF16BE ); + + /* This assert may fail if the collation sequence is deleted after this + ** vdbe program is compiled. The documentation defines this as an + ** undefined condition. A crash is usual result. + */ + assert( !pColl || pColl->xCmp ); + + if( pColl ){ + if( pMem1->enc==pColl->enc ){ + return pColl->xCmp(pColl->pUser,pMem1->n,pMem1->z,pMem2->n,pMem2->z); + }else{ + u8 origEnc = pMem1->enc; + rc = pColl->xCmp( + pColl->pUser, + sqlite3ValueBytes((sqlite3_value*)pMem1, pColl->enc), + sqlite3ValueText((sqlite3_value*)pMem1, pColl->enc), + sqlite3ValueBytes((sqlite3_value*)pMem2, pColl->enc), + sqlite3ValueText((sqlite3_value*)pMem2, pColl->enc) + ); + sqlite3ValueBytes((sqlite3_value*)pMem1, origEnc); + sqlite3ValueText((sqlite3_value*)pMem1, origEnc); + sqlite3ValueBytes((sqlite3_value*)pMem2, origEnc); + sqlite3ValueText((sqlite3_value*)pMem2, origEnc); + return rc; + } + } + /* If a NULL pointer was passed as the collate function, fall through + ** to the blob case and use memcmp(). */ + } + + /* Both values must be blobs. Compare using memcmp(). */ + rc = memcmp(pMem1->z, pMem2->z, (pMem1->n>pMem2->n)?pMem2->n:pMem1->n); + if( rc==0 ){ + rc = pMem1->n - pMem2->n; + } + return rc; +} + +/* +** Move data out of a btree key or data field and into a Mem structure. +** The data or key is taken from the entry that pCur is currently pointing +** to. offset and amt determine what portion of the data or key to retrieve. +** key is true to get the key or false to get data. The result is written +** into the pMem element. +** +** The pMem structure is assumed to be uninitialized. Any prior content +** is overwritten without being freed. +** +** 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. +*/ +int sqlite3VdbeMemFromBtree( + BtCursor *pCur, /* Cursor pointing at record to retrieve. */ + int offset, /* Offset from the start of data to return bytes from. */ + int amt, /* Number of bytes to return. */ + int key, /* If true, retrieve from the btree key, not data. */ + Mem *pMem /* OUT: Return data in this Mem structure. */ +){ + char *zData; /* Data from the btree layer */ + int available; /* Number of bytes available on the local btree page */ + + if( key ){ + zData = (char *)sqlite3BtreeKeyFetch(pCur, &available); + }else{ + zData = (char *)sqlite3BtreeDataFetch(pCur, &available); + } + + pMem->n = amt; + if( offset+amt<=available ){ + pMem->z = &zData[offset]; + pMem->flags = MEM_Blob|MEM_Ephem; + }else{ + int rc; + if( amt>NBFS-2 ){ + zData = (char *)sqliteMallocRaw(amt+2); + if( !zData ){ + return SQLITE_NOMEM; + } + pMem->flags = MEM_Blob|MEM_Dyn|MEM_Term; + pMem->xDel = 0; + }else{ + zData = &(pMem->zShort[0]); + pMem->flags = MEM_Blob|MEM_Short|MEM_Term; + } + pMem->z = zData; + pMem->enc = 0; + pMem->type = SQLITE_BLOB; + + if( key ){ + rc = sqlite3BtreeKey(pCur, offset, amt, zData); + }else{ + rc = sqlite3BtreeData(pCur, offset, amt, zData); + } + zData[amt] = 0; + zData[amt+1] = 0; + if( rc!=SQLITE_OK ){ + if( amt>NBFS-2 ){ + assert( zData!=pMem->zShort ); + assert( pMem->flags & MEM_Dyn ); + sqliteFree(zData); + } else { + assert( zData==pMem->zShort ); + assert( pMem->flags & MEM_Short ); + } + return rc; + } + } + + return SQLITE_OK; +} + +#ifndef NDEBUG +/* +** Perform various checks on the memory cell pMem. An assert() will +** fail if pMem is internally inconsistent. +*/ +void sqlite3VdbeMemSanity(Mem *pMem, u8 db_enc){ + int flags = pMem->flags; + assert( flags!=0 ); /* Must define some type */ + if( pMem->flags & (MEM_Str|MEM_Blob) ){ + int x = pMem->flags & (MEM_Static|MEM_Dyn|MEM_Ephem|MEM_Short); + assert( x!=0 ); /* Strings must define a string subtype */ + assert( (x & (x-1))==0 ); /* Only one string subtype can be defined */ + assert( pMem->z!=0 ); /* Strings must have a value */ + /* Mem.z points to Mem.zShort iff the subtype is MEM_Short */ + assert( (pMem->flags & MEM_Short)==0 || pMem->z==pMem->zShort ); + assert( (pMem->flags & MEM_Short)!=0 || pMem->z!=pMem->zShort ); + /* No destructor unless there is MEM_Dyn */ + assert( pMem->xDel==0 || (pMem->flags & MEM_Dyn)!=0 ); + + if( (flags & MEM_Str) ){ + assert( pMem->enc==SQLITE_UTF8 || + pMem->enc==SQLITE_UTF16BE || + pMem->enc==SQLITE_UTF16LE + ); + /* If the string is UTF-8 encoded and nul terminated, then pMem->n + ** must be the length of the string. (Later:) If the database file + ** has been corrupted, '\000' characters might have been inserted + ** into the middle of the string. In that case, the strlen() might + ** be less. + */ + if( pMem->enc==SQLITE_UTF8 && (flags & MEM_Term) ){ + assert( strlen(pMem->z)<=pMem->n ); + assert( pMem->z[pMem->n]==0 ); + } + } + }else{ + /* Cannot define a string subtype for non-string objects */ + assert( (pMem->flags & (MEM_Static|MEM_Dyn|MEM_Ephem|MEM_Short))==0 ); + assert( pMem->xDel==0 ); + } + /* MEM_Null excludes all other types */ + assert( (pMem->flags&(MEM_Str|MEM_Int|MEM_Real|MEM_Blob))==0 + || (pMem->flags&MEM_Null)==0 ); + /* If the MEM is both real and integer, the values are equal */ + assert( (pMem->flags & (MEM_Int|MEM_Real))!=(MEM_Int|MEM_Real) + || pMem->r==pMem->i ); +} +#endif + +/* 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. +*/ +const void *sqlite3ValueText(sqlite3_value* pVal, u8 enc){ + if( !pVal ) return 0; + assert( enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE || enc==SQLITE_UTF8); + + if( pVal->flags&MEM_Null ){ + return 0; + } + if( pVal->flags&MEM_Str ){ + sqlite3VdbeChangeEncoding(pVal, enc); + }else if( !(pVal->flags&MEM_Blob) ){ + sqlite3VdbeMemStringify(pVal, enc); + } + return (const void *)(pVal->z); +} + +/* +** Create a new sqlite3_value object. +*/ +sqlite3_value* sqlite3ValueNew(void){ + Mem *p = sqliteMalloc(sizeof(*p)); + if( p ){ + p->flags = MEM_Null; + p->type = SQLITE_NULL; + } + return p; +} + +/* +** 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", "NULL", "'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( + Expr *pExpr, + u8 enc, + u8 affinity, + sqlite3_value **ppVal +){ + int op; + char *zVal = 0; + sqlite3_value *pVal = 0; + + if( !pExpr ){ + *ppVal = 0; + return SQLITE_OK; + } + op = pExpr->op; + + if( op==TK_STRING || op==TK_FLOAT || op==TK_INTEGER ){ + zVal = sqliteStrNDup(pExpr->token.z, pExpr->token.n); + pVal = sqlite3ValueNew(); + if( !zVal || !pVal ) goto no_mem; + sqlite3Dequote(zVal); + sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, sqlite3FreeX); + if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_NONE ){ + sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, enc); + }else{ + sqlite3ValueApplyAffinity(pVal, affinity, enc); + } + }else if( op==TK_UMINUS ) { + if( SQLITE_OK==sqlite3ValueFromExpr(pExpr->pLeft, enc, affinity, &pVal) ){ + pVal->i = -1 * pVal->i; + pVal->r = -1.0 * pVal->r; + } + } +#ifndef SQLITE_OMIT_BLOB_LITERAL + else if( op==TK_BLOB ){ + int nVal; + pVal = sqlite3ValueNew(); + zVal = sqliteStrNDup(pExpr->token.z+1, pExpr->token.n-1); + if( !zVal || !pVal ) goto no_mem; + sqlite3Dequote(zVal); + nVal = strlen(zVal)/2; + sqlite3VdbeMemSetStr(pVal, sqlite3HexToBlob(zVal), nVal, 0, sqlite3FreeX); + sqliteFree(zVal); + } +#endif + + *ppVal = pVal; + return SQLITE_OK; + +no_mem: + sqliteFree(zVal); + sqlite3ValueFree(pVal); + *ppVal = 0; + return SQLITE_NOMEM; +} + +/* +** Change the string value of an sqlite3_value object +*/ +void sqlite3ValueSetStr( + sqlite3_value *v, + int n, + const void *z, + u8 enc, + void (*xDel)(void*) +){ + if( v ) sqlite3VdbeMemSetStr((Mem *)v, z, n, enc, xDel); +} + +/* +** Free an sqlite3_value object +*/ +void sqlite3ValueFree(sqlite3_value *v){ + if( !v ) return; + sqlite3ValueSetStr(v, 0, 0, SQLITE_UTF8, SQLITE_STATIC); + sqliteFree(v); +} + +/* +** Return the number of bytes in the sqlite3_value object assuming +** that it uses the encoding "enc" +*/ +int sqlite3ValueBytes(sqlite3_value *pVal, u8 enc){ + Mem *p = (Mem*)pVal; + if( (p->flags & MEM_Blob)!=0 || sqlite3ValueText(pVal, enc) ){ + return p->n; + } + return 0; +} |