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Artifact 2f9d672af5260f0145787e1dc2c6985414987cc0dc575133a0dc17dda767d868:


     1  /*
     2  ** 2004 May 26
     3  **
     4  ** The author disclaims copyright to this source code.  In place of
     5  ** a legal notice, here is a blessing:
     6  **
     7  **    May you do good and not evil.
     8  **    May you find forgiveness for yourself and forgive others.
     9  **    May you share freely, never taking more than you give.
    10  **
    11  *************************************************************************
    12  **
    13  ** This file contains code use to manipulate "Mem" structure.  A "Mem"
    14  ** stores a single value in the VDBE.  Mem is an opaque structure visible
    15  ** only within the VDBE.  Interface routines refer to a Mem using the
    16  ** name sqlite_value
    17  */
    18  #include "sqliteInt.h"
    19  #include "vdbeInt.h"
    20  
    21  #ifdef SQLITE_DEBUG
    22  /*
    23  ** Check invariants on a Mem object.
    24  **
    25  ** This routine is intended for use inside of assert() statements, like
    26  ** this:    assert( sqlite3VdbeCheckMemInvariants(pMem) );
    27  */
    28  int sqlite3VdbeCheckMemInvariants(Mem *p){
    29    /* If MEM_Dyn is set then Mem.xDel!=0.  
    30    ** Mem.xDel might not be initialized if MEM_Dyn is clear.
    31    */
    32    assert( (p->flags & MEM_Dyn)==0 || p->xDel!=0 );
    33  
    34    /* MEM_Dyn may only be set if Mem.szMalloc==0.  In this way we
    35    ** ensure that if Mem.szMalloc>0 then it is safe to do
    36    ** Mem.z = Mem.zMalloc without having to check Mem.flags&MEM_Dyn.
    37    ** That saves a few cycles in inner loops. */
38 assert( (p->flags & MEM_Dyn)==0 || p->szMalloc==0 );
39 40 /* Cannot be both MEM_Int and MEM_Real at the same time */ 41 assert( (p->flags & (MEM_Int|MEM_Real))!=(MEM_Int|MEM_Real) ); 42 43 if( p->flags & MEM_Null ){ 44 /* Cannot be both MEM_Null and some other type */ 45 assert( (p->flags & (MEM_Int|MEM_Real|MEM_Str|MEM_Blob 46 |MEM_RowSet|MEM_Frame|MEM_Agg|MEM_Zero))==0 ); 47 48 /* If MEM_Null is set, then either the value is a pure NULL (the usual 49 ** case) or it is a pointer set using sqlite3_bind_pointer() or 50 ** sqlite3_result_pointer(). If a pointer, then MEM_Term must also be 51 ** set. 52 */ 53 if( (p->flags & (MEM_Term|MEM_Subtype))==(MEM_Term|MEM_Subtype) ){ 54 /* This is a pointer type. There may be a flag to indicate what to 55 ** do with the pointer. */ 56 assert( ((p->flags&MEM_Dyn)!=0 ? 1 : 0) + 57 ((p->flags&MEM_Ephem)!=0 ? 1 : 0) + 58 ((p->flags&MEM_Static)!=0 ? 1 : 0) <= 1 ); 59 60 /* No other bits set */ 61 assert( (p->flags & ~(MEM_Null|MEM_Term|MEM_Subtype 62 |MEM_Dyn|MEM_Ephem|MEM_Static))==0 ); 63 }else{ 64 /* A pure NULL might have other flags, such as MEM_Static, MEM_Dyn, 65 ** MEM_Ephem, MEM_Cleared, or MEM_Subtype */ 66 } 67 }else{ 68 /* The MEM_Cleared bit is only allowed on NULLs */ 69 assert( (p->flags & MEM_Cleared)==0 ); 70 } 71 72 /* The szMalloc field holds the correct memory allocation size */ 73 assert( p->szMalloc==0 74 || p->szMalloc==sqlite3DbMallocSize(p->db,p->zMalloc) ); 75 76 /* If p holds a string or blob, the Mem.z must point to exactly 77 ** one of the following: 78 ** 79 ** (1) Memory in Mem.zMalloc and managed by the Mem object 80 ** (2) Memory to be freed using Mem.xDel 81 ** (3) An ephemeral string or blob 82 ** (4) A static string or blob 83 */ 84 if( (p->flags & (MEM_Str|MEM_Blob)) && p->n>0 ){ 85 assert( 86 ((p->szMalloc>0 && p->z==p->zMalloc)? 1 : 0) + 87 ((p->flags&MEM_Dyn)!=0 ? 1 : 0) + 88 ((p->flags&MEM_Ephem)!=0 ? 1 : 0) + 89 ((p->flags&MEM_Static)!=0 ? 1 : 0) == 1 90 ); 91 } 92 return 1; 93 } 94 #endif 95 96 97 /* 98 ** If pMem is an object with a valid string representation, this routine 99 ** ensures the internal encoding for the string representation is 100 ** 'desiredEnc', one of SQLITE_UTF8, SQLITE_UTF16LE or SQLITE_UTF16BE. 101 ** 102 ** If pMem is not a string object, or the encoding of the string 103 ** representation is already stored using the requested encoding, then this 104 ** routine is a no-op. 105 ** 106 ** SQLITE_OK is returned if the conversion is successful (or not required). 107 ** SQLITE_NOMEM may be returned if a malloc() fails during conversion 108 ** between formats. 109 */ 110 int sqlite3VdbeChangeEncoding(Mem *pMem, int desiredEnc){ 111 #ifndef SQLITE_OMIT_UTF16 112 int rc; 113 #endif 114 assert( (pMem->flags&MEM_RowSet)==0 ); 115 assert( desiredEnc==SQLITE_UTF8 || desiredEnc==SQLITE_UTF16LE 116 || desiredEnc==SQLITE_UTF16BE ); 117 if( !(pMem->flags&MEM_Str) || pMem->enc==desiredEnc ){ 118 return SQLITE_OK; 119 } 120 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 121 #ifdef SQLITE_OMIT_UTF16 122 return SQLITE_ERROR; 123 #else 124 125 /* MemTranslate() may return SQLITE_OK or SQLITE_NOMEM. If NOMEM is returned, 126 ** then the encoding of the value may not have changed. 127 */ 128 rc = sqlite3VdbeMemTranslate(pMem, (u8)desiredEnc); 129 assert(rc==SQLITE_OK || rc==SQLITE_NOMEM); 130 assert(rc==SQLITE_OK || pMem->enc!=desiredEnc); 131 assert(rc==SQLITE_NOMEM || pMem->enc==desiredEnc); 132 return rc; 133 #endif 134 } 135 136 /* 137 ** Make sure pMem->z points to a writable allocation of at least 138 ** min(n,32) bytes. 139 ** 140 ** If the bPreserve argument is true, then copy of the content of 141 ** pMem->z into the new allocation. pMem must be either a string or 142 ** blob if bPreserve is true. If bPreserve is false, any prior content 143 ** in pMem->z is discarded. 144 */ 145 SQLITE_NOINLINE int sqlite3VdbeMemGrow(Mem *pMem, int n, int bPreserve){ 146 assert( sqlite3VdbeCheckMemInvariants(pMem) ); 147 assert( (pMem->flags&MEM_RowSet)==0 ); 148 testcase( pMem->db==0 ); 149 150 /* If the bPreserve flag is set to true, then the memory cell must already 151 ** contain a valid string or blob value. */ 152 assert( bPreserve==0 || pMem->flags&(MEM_Blob|MEM_Str) ); 153 testcase( bPreserve && pMem->z==0 ); 154 155 assert( pMem->szMalloc==0 156 || pMem->szMalloc==sqlite3DbMallocSize(pMem->db, pMem->zMalloc) ); 157 if( n<32 ) n = 32; 158 if( bPreserve && pMem->szMalloc>0 && pMem->z==pMem->zMalloc ){ 159 pMem->z = pMem->zMalloc = sqlite3DbReallocOrFree(pMem->db, pMem->z, n); 160 bPreserve = 0; 161 }else{ 162 if( pMem->szMalloc>0 ) sqlite3DbFreeNN(pMem->db, pMem->zMalloc); 163 pMem->zMalloc = sqlite3DbMallocRaw(pMem->db, n); 164 } 165 if( pMem->zMalloc==0 ){ 166 sqlite3VdbeMemSetNull(pMem); 167 pMem->z = 0; 168 pMem->szMalloc = 0; 169 return SQLITE_NOMEM_BKPT; 170 }else{ 171 pMem->szMalloc = sqlite3DbMallocSize(pMem->db, pMem->zMalloc); 172 } 173 174 if( bPreserve && pMem->z && ALWAYS(pMem->z!=pMem->zMalloc) ){ 175 memcpy(pMem->zMalloc, pMem->z, pMem->n); 176 } 177 if( (pMem->flags&MEM_Dyn)!=0 ){ 178 assert( pMem->xDel!=0 && pMem->xDel!=SQLITE_DYNAMIC ); 179 pMem->xDel((void *)(pMem->z)); 180 } 181 182 pMem->z = pMem->zMalloc; 183 pMem->flags &= ~(MEM_Dyn|MEM_Ephem|MEM_Static); 184 return SQLITE_OK; 185 } 186 187 /* 188 ** Change the pMem->zMalloc allocation to be at least szNew bytes. 189 ** If pMem->zMalloc already meets or exceeds the requested size, this 190 ** routine is a no-op. 191 ** 192 ** Any prior string or blob content in the pMem object may be discarded. 193 ** The pMem->xDel destructor is called, if it exists. Though MEM_Str 194 ** and MEM_Blob values may be discarded, MEM_Int, MEM_Real, and MEM_Null 195 ** values are preserved. 196 ** 197 ** Return SQLITE_OK on success or an error code (probably SQLITE_NOMEM) 198 ** if unable to complete the resizing. 199 */ 200 int sqlite3VdbeMemClearAndResize(Mem *pMem, int szNew){ 201 assert( szNew>0 ); 202 assert( (pMem->flags & MEM_Dyn)==0 || pMem->szMalloc==0 ); 203 if( pMem->szMalloc<szNew ){ 204 return sqlite3VdbeMemGrow(pMem, szNew, 0); 205 } 206 assert( (pMem->flags & MEM_Dyn)==0 ); 207 pMem->z = pMem->zMalloc; 208 pMem->flags &= (MEM_Null|MEM_Int|MEM_Real); 209 return SQLITE_OK; 210 } 211 212 /* 213 ** Change pMem so that its MEM_Str or MEM_Blob value is stored in 214 ** MEM.zMalloc, where it can be safely written. 215 ** 216 ** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails. 217 */ 218 int sqlite3VdbeMemMakeWriteable(Mem *pMem){ 219 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 220 assert( (pMem->flags&MEM_RowSet)==0 ); 221 if( (pMem->flags & (MEM_Str|MEM_Blob))!=0 ){ 222 if( ExpandBlob(pMem) ) return SQLITE_NOMEM; 223 if( pMem->szMalloc==0 || pMem->z!=pMem->zMalloc ){ 224 if( sqlite3VdbeMemGrow(pMem, pMem->n + 2, 1) ){ 225 return SQLITE_NOMEM_BKPT; 226 } 227 pMem->z[pMem->n] = 0; 228 pMem->z[pMem->n+1] = 0; 229 pMem->flags |= MEM_Term; 230 } 231 } 232 pMem->flags &= ~MEM_Ephem; 233 #ifdef SQLITE_DEBUG 234 pMem->pScopyFrom = 0; 235 #endif 236 237 return SQLITE_OK; 238 } 239 240 /* 241 ** If the given Mem* has a zero-filled tail, turn it into an ordinary 242 ** blob stored in dynamically allocated space. 243 */ 244 #ifndef SQLITE_OMIT_INCRBLOB 245 int sqlite3VdbeMemExpandBlob(Mem *pMem){ 246 int nByte; 247 assert( pMem->flags & MEM_Zero ); 248 assert( pMem->flags&MEM_Blob ); 249 assert( (pMem->flags&MEM_RowSet)==0 ); 250 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 251 252 /* Set nByte to the number of bytes required to store the expanded blob. */ 253 nByte = pMem->n + pMem->u.nZero; 254 if( nByte<=0 ){ 255 nByte = 1; 256 } 257 if( sqlite3VdbeMemGrow(pMem, nByte, 1) ){ 258 return SQLITE_NOMEM_BKPT; 259 } 260 261 memset(&pMem->z[pMem->n], 0, pMem->u.nZero); 262 pMem->n += pMem->u.nZero; 263 pMem->flags &= ~(MEM_Zero|MEM_Term); 264 return SQLITE_OK; 265 } 266 #endif 267 268 /* 269 ** It is already known that pMem contains an unterminated string. 270 ** Add the zero terminator. 271 */ 272 static SQLITE_NOINLINE int vdbeMemAddTerminator(Mem *pMem){ 273 if( sqlite3VdbeMemGrow(pMem, pMem->n+2, 1) ){ 274 return SQLITE_NOMEM_BKPT; 275 } 276 pMem->z[pMem->n] = 0; 277 pMem->z[pMem->n+1] = 0; 278 pMem->flags |= MEM_Term; 279 return SQLITE_OK; 280 } 281 282 /* 283 ** Make sure the given Mem is \u0000 terminated. 284 */ 285 int sqlite3VdbeMemNulTerminate(Mem *pMem){ 286 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 287 testcase( (pMem->flags & (MEM_Term|MEM_Str))==(MEM_Term|MEM_Str) ); 288 testcase( (pMem->flags & (MEM_Term|MEM_Str))==0 ); 289 if( (pMem->flags & (MEM_Term|MEM_Str))!=MEM_Str ){ 290 return SQLITE_OK; /* Nothing to do */ 291 }else{ 292 return vdbeMemAddTerminator(pMem); 293 } 294 } 295 296 /* 297 ** Add MEM_Str to the set of representations for the given Mem. Numbers 298 ** are converted using sqlite3_snprintf(). Converting a BLOB to a string 299 ** is a no-op. 300 ** 301 ** Existing representations MEM_Int and MEM_Real are invalidated if 302 ** bForce is true but are retained if bForce is false. 303 ** 304 ** A MEM_Null value will never be passed to this function. This function is 305 ** used for converting values to text for returning to the user (i.e. via 306 ** sqlite3_value_text()), or for ensuring that values to be used as btree 307 ** keys are strings. In the former case a NULL pointer is returned the 308 ** user and the latter is an internal programming error. 309 */ 310 int sqlite3VdbeMemStringify(Mem *pMem, u8 enc, u8 bForce){ 311 int fg = pMem->flags; 312 const int nByte = 32; 313 314 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 315 assert( !(fg&MEM_Zero) ); 316 assert( !(fg&(MEM_Str|MEM_Blob)) ); 317 assert( fg&(MEM_Int|MEM_Real) ); 318 assert( (pMem->flags&MEM_RowSet)==0 ); 319 assert( EIGHT_BYTE_ALIGNMENT(pMem) ); 320 321 322 if( sqlite3VdbeMemClearAndResize(pMem, nByte) ){ 323 pMem->enc = 0; 324 return SQLITE_NOMEM_BKPT; 325 } 326 327 /* For a Real or Integer, use sqlite3_snprintf() to produce the UTF-8 328 ** string representation of the value. Then, if the required encoding 329 ** is UTF-16le or UTF-16be do a translation. 330 ** 331 ** FIX ME: It would be better if sqlite3_snprintf() could do UTF-16. 332 */ 333 if( fg & MEM_Int ){ 334 sqlite3_snprintf(nByte, pMem->z, "%lld", pMem->u.i); 335 }else{ 336 assert( fg & MEM_Real ); 337 sqlite3_snprintf(nByte, pMem->z, "%!.15g", pMem->u.r); 338 } 339 pMem->n = sqlite3Strlen30(pMem->z); 340 pMem->enc = SQLITE_UTF8; 341 pMem->flags |= MEM_Str|MEM_Term; 342 if( bForce ) pMem->flags &= ~(MEM_Int|MEM_Real); 343 sqlite3VdbeChangeEncoding(pMem, enc); 344 return SQLITE_OK; 345 } 346 347 /* 348 ** Memory cell pMem contains the context of an aggregate function. 349 ** This routine calls the finalize method for that function. The 350 ** result of the aggregate is stored back into pMem. 351 ** 352 ** Return SQLITE_ERROR if the finalizer reports an error. SQLITE_OK 353 ** otherwise. 354 */ 355 int sqlite3VdbeMemFinalize(Mem *pMem, FuncDef *pFunc){ 356 int rc = SQLITE_OK; 357 if( ALWAYS(pFunc && pFunc->xFinalize) ){ 358 sqlite3_context ctx; 359 Mem t; 360 assert( (pMem->flags & MEM_Null)!=0 || pFunc==pMem->u.pDef ); 361 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 362 memset(&ctx, 0, sizeof(ctx)); 363 memset(&t, 0, sizeof(t)); 364 t.flags = MEM_Null; 365 t.db = pMem->db; 366 ctx.pOut = &t; 367 ctx.pMem = pMem; 368 ctx.pFunc = pFunc; 369 pFunc->xFinalize(&ctx); /* IMP: R-24505-23230 */ 370 assert( (pMem->flags & MEM_Dyn)==0 ); 371 if( pMem->szMalloc>0 ) sqlite3DbFreeNN(pMem->db, pMem->zMalloc); 372 memcpy(pMem, &t, sizeof(t)); 373 rc = ctx.isError; 374 } 375 return rc; 376 } 377 378 /* 379 ** If the memory cell contains a value that must be freed by 380 ** invoking the external callback in Mem.xDel, then this routine 381 ** will free that value. It also sets Mem.flags to MEM_Null. 382 ** 383 ** This is a helper routine for sqlite3VdbeMemSetNull() and 384 ** for sqlite3VdbeMemRelease(). Use those other routines as the 385 ** entry point for releasing Mem resources. 386 */ 387 static SQLITE_NOINLINE void vdbeMemClearExternAndSetNull(Mem *p){ 388 assert( p->db==0 || sqlite3_mutex_held(p->db->mutex) ); 389 assert( VdbeMemDynamic(p) ); 390 if( p->flags&MEM_Agg ){ 391 sqlite3VdbeMemFinalize(p, p->u.pDef); 392 assert( (p->flags & MEM_Agg)==0 ); 393 testcase( p->flags & MEM_Dyn ); 394 } 395 if( p->flags&MEM_Dyn ){ 396 assert( (p->flags&MEM_RowSet)==0 ); 397 assert( p->xDel!=SQLITE_DYNAMIC && p->xDel!=0 ); 398 p->xDel((void *)p->z); 399 }else if( p->flags&MEM_RowSet ){ 400 sqlite3RowSetClear(p->u.pRowSet); 401 }else if( p->flags&MEM_Frame ){ 402 VdbeFrame *pFrame = p->u.pFrame; 403 pFrame->pParent = pFrame->v->pDelFrame; 404 pFrame->v->pDelFrame = pFrame; 405 } 406 p->flags = MEM_Null; 407 } 408 409 /* 410 ** Release memory held by the Mem p, both external memory cleared 411 ** by p->xDel and memory in p->zMalloc. 412 ** 413 ** This is a helper routine invoked by sqlite3VdbeMemRelease() in 414 ** the unusual case where there really is memory in p that needs 415 ** to be freed. 416 */ 417 static SQLITE_NOINLINE void vdbeMemClear(Mem *p){ 418 if( VdbeMemDynamic(p) ){ 419 vdbeMemClearExternAndSetNull(p); 420 } 421 if( p->szMalloc ){ 422 sqlite3DbFreeNN(p->db, p->zMalloc); 423 p->szMalloc = 0; 424 } 425 p->z = 0; 426 } 427 428 /* 429 ** Release any memory resources held by the Mem. Both the memory that is 430 ** free by Mem.xDel and the Mem.zMalloc allocation are freed. 431 ** 432 ** Use this routine prior to clean up prior to abandoning a Mem, or to 433 ** reset a Mem back to its minimum memory utilization. 434 ** 435 ** Use sqlite3VdbeMemSetNull() to release just the Mem.xDel space 436 ** prior to inserting new content into the Mem. 437 */ 438 void sqlite3VdbeMemRelease(Mem *p){ 439 assert( sqlite3VdbeCheckMemInvariants(p) ); 440 if( VdbeMemDynamic(p) || p->szMalloc ){ 441 vdbeMemClear(p); 442 } 443 } 444 445 /* 446 ** Convert a 64-bit IEEE double into a 64-bit signed integer. 447 ** If the double is out of range of a 64-bit signed integer then 448 ** return the closest available 64-bit signed integer. 449 */ 450 static SQLITE_NOINLINE i64 doubleToInt64(double r){ 451 #ifdef SQLITE_OMIT_FLOATING_POINT 452 /* When floating-point is omitted, double and int64 are the same thing */ 453 return r; 454 #else 455 /* 456 ** Many compilers we encounter do not define constants for the 457 ** minimum and maximum 64-bit integers, or they define them 458 ** inconsistently. And many do not understand the "LL" notation. 459 ** So we define our own static constants here using nothing 460 ** larger than a 32-bit integer constant. 461 */ 462 static const i64 maxInt = LARGEST_INT64; 463 static const i64 minInt = SMALLEST_INT64; 464 465 if( r<=(double)minInt ){ 466 return minInt; 467 }else if( r>=(double)maxInt ){ 468 return maxInt; 469 }else{ 470 return (i64)r; 471 } 472 #endif 473 } 474 475 /* 476 ** Return some kind of integer value which is the best we can do 477 ** at representing the value that *pMem describes as an integer. 478 ** If pMem is an integer, then the value is exact. If pMem is 479 ** a floating-point then the value returned is the integer part. 480 ** If pMem is a string or blob, then we make an attempt to convert 481 ** it into an integer and return that. If pMem represents an 482 ** an SQL-NULL value, return 0. 483 ** 484 ** If pMem represents a string value, its encoding might be changed. 485 */ 486 static SQLITE_NOINLINE i64 memIntValue(Mem *pMem){ 487 i64 value = 0; 488 sqlite3Atoi64(pMem->z, &value, pMem->n, pMem->enc); 489 return value; 490 } 491 i64 sqlite3VdbeIntValue(Mem *pMem){ 492 int flags; 493 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 494 assert( EIGHT_BYTE_ALIGNMENT(pMem) ); 495 flags = pMem->flags; 496 if( flags & MEM_Int ){ 497 return pMem->u.i; 498 }else if( flags & MEM_Real ){ 499 return doubleToInt64(pMem->u.r); 500 }else if( flags & (MEM_Str|MEM_Blob) ){ 501 assert( pMem->z || pMem->n==0 ); 502 return memIntValue(pMem); 503 }else{ 504 return 0; 505 } 506 } 507 508 /* 509 ** Return the best representation of pMem that we can get into a 510 ** double. If pMem is already a double or an integer, return its 511 ** value. If it is a string or blob, try to convert it to a double. 512 ** If it is a NULL, return 0.0. 513 */ 514 static SQLITE_NOINLINE double memRealValue(Mem *pMem){ 515 /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */ 516 double val = (double)0; 517 sqlite3AtoF(pMem->z, &val, pMem->n, pMem->enc); 518 return val; 519 } 520 double sqlite3VdbeRealValue(Mem *pMem){ 521 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 522 assert( EIGHT_BYTE_ALIGNMENT(pMem) ); 523 if( pMem->flags & MEM_Real ){ 524 return pMem->u.r; 525 }else if( pMem->flags & MEM_Int ){ 526 return (double)pMem->u.i; 527 }else if( pMem->flags & (MEM_Str|MEM_Blob) ){ 528 return memRealValue(pMem); 529 }else{ 530 /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */ 531 return (double)0; 532 } 533 } 534 535 /* 536 ** The MEM structure is already a MEM_Real. Try to also make it a 537 ** MEM_Int if we can. 538 */ 539 void sqlite3VdbeIntegerAffinity(Mem *pMem){ 540 i64 ix; 541 assert( pMem->flags & MEM_Real ); 542 assert( (pMem->flags & MEM_RowSet)==0 ); 543 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 544 assert( EIGHT_BYTE_ALIGNMENT(pMem) ); 545 546 ix = doubleToInt64(pMem->u.r); 547 548 /* Only mark the value as an integer if 549 ** 550 ** (1) the round-trip conversion real->int->real is a no-op, and 551 ** (2) The integer is neither the largest nor the smallest 552 ** possible integer (ticket #3922) 553 ** 554 ** The second and third terms in the following conditional enforces 555 ** the second condition under the assumption that addition overflow causes 556 ** values to wrap around. 557 */ 558 if( pMem->u.r==ix && ix>SMALLEST_INT64 && ix<LARGEST_INT64 ){ 559 pMem->u.i = ix; 560 MemSetTypeFlag(pMem, MEM_Int); 561 } 562 } 563 564 /* 565 ** Convert pMem to type integer. Invalidate any prior representations. 566 */ 567 int sqlite3VdbeMemIntegerify(Mem *pMem){ 568 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 569 assert( (pMem->flags & MEM_RowSet)==0 ); 570 assert( EIGHT_BYTE_ALIGNMENT(pMem) ); 571 572 pMem->u.i = sqlite3VdbeIntValue(pMem); 573 MemSetTypeFlag(pMem, MEM_Int); 574 return SQLITE_OK; 575 } 576 577 /* 578 ** Convert pMem so that it is of type MEM_Real. 579 ** Invalidate any prior representations. 580 */ 581 int sqlite3VdbeMemRealify(Mem *pMem){ 582 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 583 assert( EIGHT_BYTE_ALIGNMENT(pMem) ); 584 585 pMem->u.r = sqlite3VdbeRealValue(pMem); 586 MemSetTypeFlag(pMem, MEM_Real); 587 return SQLITE_OK; 588 } 589 590 /* 591 ** Convert pMem so that it has types MEM_Real or MEM_Int or both. 592 ** Invalidate any prior representations. 593 ** 594 ** Every effort is made to force the conversion, even if the input 595 ** is a string that does not look completely like a number. Convert 596 ** as much of the string as we can and ignore the rest. 597 */ 598 int sqlite3VdbeMemNumerify(Mem *pMem){ 599 if( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))==0 ){ 600 assert( (pMem->flags & (MEM_Blob|MEM_Str))!=0 ); 601 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 602 if( 0==sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc) ){ 603 MemSetTypeFlag(pMem, MEM_Int); 604 }else{ 605 pMem->u.r = sqlite3VdbeRealValue(pMem); 606 MemSetTypeFlag(pMem, MEM_Real); 607 sqlite3VdbeIntegerAffinity(pMem); 608 } 609 } 610 assert( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))!=0 ); 611 pMem->flags &= ~(MEM_Str|MEM_Blob|MEM_Zero); 612 return SQLITE_OK; 613 } 614 615 /* 616 ** Cast the datatype of the value in pMem according to the affinity 617 ** "aff". Casting is different from applying affinity in that a cast 618 ** is forced. In other words, the value is converted into the desired 619 ** affinity even if that results in loss of data. This routine is 620 ** used (for example) to implement the SQL "cast()" operator. 621 */ 622 void sqlite3VdbeMemCast(Mem *pMem, u8 aff, u8 encoding){ 623 if( pMem->flags & MEM_Null ) return; 624 switch( aff ){ 625 case SQLITE_AFF_BLOB: { /* Really a cast to BLOB */ 626 if( (pMem->flags & MEM_Blob)==0 ){ 627 sqlite3ValueApplyAffinity(pMem, SQLITE_AFF_TEXT, encoding); 628 assert( pMem->flags & MEM_Str || pMem->db->mallocFailed ); 629 if( pMem->flags & MEM_Str ) MemSetTypeFlag(pMem, MEM_Blob); 630 }else{ 631 pMem->flags &= ~(MEM_TypeMask&~MEM_Blob); 632 } 633 break; 634 } 635 case SQLITE_AFF_NUMERIC: { 636 sqlite3VdbeMemNumerify(pMem); 637 break; 638 } 639 case SQLITE_AFF_INTEGER: { 640 sqlite3VdbeMemIntegerify(pMem); 641 break; 642 } 643 case SQLITE_AFF_REAL: { 644 sqlite3VdbeMemRealify(pMem); 645 break; 646 } 647 default: { 648 assert( aff==SQLITE_AFF_TEXT ); 649 assert( MEM_Str==(MEM_Blob>>3) ); 650 pMem->flags |= (pMem->flags&MEM_Blob)>>3; 651 sqlite3ValueApplyAffinity(pMem, SQLITE_AFF_TEXT, encoding); 652 assert( pMem->flags & MEM_Str || pMem->db->mallocFailed ); 653 pMem->flags &= ~(MEM_Int|MEM_Real|MEM_Blob|MEM_Zero); 654 break; 655 } 656 } 657 } 658 659 /* 660 ** Initialize bulk memory to be a consistent Mem object. 661 ** 662 ** The minimum amount of initialization feasible is performed. 663 */ 664 void sqlite3VdbeMemInit(Mem *pMem, sqlite3 *db, u16 flags){ 665 assert( (flags & ~MEM_TypeMask)==0 ); 666 pMem->flags = flags; 667 pMem->db = db; 668 pMem->szMalloc = 0; 669 } 670 671 672 /* 673 ** Delete any previous value and set the value stored in *pMem to NULL. 674 ** 675 ** This routine calls the Mem.xDel destructor to dispose of values that 676 ** require the destructor. But it preserves the Mem.zMalloc memory allocation. 677 ** To free all resources, use sqlite3VdbeMemRelease(), which both calls this 678 ** routine to invoke the destructor and deallocates Mem.zMalloc. 679 ** 680 ** Use this routine to reset the Mem prior to insert a new value. 681 ** 682 ** Use sqlite3VdbeMemRelease() to complete erase the Mem prior to abandoning it. 683 */ 684 void sqlite3VdbeMemSetNull(Mem *pMem){ 685 if( VdbeMemDynamic(pMem) ){ 686 vdbeMemClearExternAndSetNull(pMem); 687 }else{ 688 pMem->flags = MEM_Null; 689 } 690 } 691 void sqlite3ValueSetNull(sqlite3_value *p){ 692 sqlite3VdbeMemSetNull((Mem*)p); 693 } 694 695 /* 696 ** Delete any previous value and set the value to be a BLOB of length 697 ** n containing all zeros. 698 */ 699 void sqlite3VdbeMemSetZeroBlob(Mem *pMem, int n){ 700 sqlite3VdbeMemRelease(pMem); 701 pMem->flags = MEM_Blob|MEM_Zero; 702 pMem->n = 0; 703 if( n<0 ) n = 0; 704 pMem->u.nZero = n; 705 pMem->enc = SQLITE_UTF8; 706 pMem->z = 0; 707 } 708 709 /* 710 ** The pMem is known to contain content that needs to be destroyed prior 711 ** to a value change. So invoke the destructor, then set the value to 712 ** a 64-bit integer. 713 */ 714 static SQLITE_NOINLINE void vdbeReleaseAndSetInt64(Mem *pMem, i64 val){ 715 sqlite3VdbeMemSetNull(pMem); 716 pMem->u.i = val; 717 pMem->flags = MEM_Int; 718 } 719 720 /* 721 ** Delete any previous value and set the value stored in *pMem to val, 722 ** manifest type INTEGER. 723 */ 724 void sqlite3VdbeMemSetInt64(Mem *pMem, i64 val){ 725 if( VdbeMemDynamic(pMem) ){ 726 vdbeReleaseAndSetInt64(pMem, val); 727 }else{ 728 pMem->u.i = val; 729 pMem->flags = MEM_Int; 730 } 731 } 732 733 /* A no-op destructor */ 734 static void sqlite3NoopDestructor(void *p){ UNUSED_PARAMETER(p); } 735 736 /* 737 ** Set the value stored in *pMem should already be a NULL. 738 ** Also store a pointer to go with it. 739 */ 740 void sqlite3VdbeMemSetPointer( 741 Mem *pMem, 742 void *pPtr, 743 const char *zPType, 744 void (*xDestructor)(void*) 745 ){ 746 assert( pMem->flags==MEM_Null ); 747 pMem->u.zPType = zPType ? zPType : ""; 748 pMem->z = pPtr; 749 pMem->flags = MEM_Null|MEM_Dyn|MEM_Subtype|MEM_Term; 750 pMem->eSubtype = 'p'; 751 pMem->xDel = xDestructor ? xDestructor : sqlite3NoopDestructor; 752 } 753 754 #ifndef SQLITE_OMIT_FLOATING_POINT 755 /* 756 ** Delete any previous value and set the value stored in *pMem to val, 757 ** manifest type REAL. 758 */ 759 void sqlite3VdbeMemSetDouble(Mem *pMem, double val){ 760 sqlite3VdbeMemSetNull(pMem); 761 if( !sqlite3IsNaN(val) ){ 762 pMem->u.r = val; 763 pMem->flags = MEM_Real; 764 } 765 } 766 #endif 767 768 /* 769 ** Delete any previous value and set the value of pMem to be an 770 ** empty boolean index. 771 */ 772 void sqlite3VdbeMemSetRowSet(Mem *pMem){ 773 sqlite3 *db = pMem->db; 774 assert( db!=0 ); 775 assert( (pMem->flags & MEM_RowSet)==0 ); 776 sqlite3VdbeMemRelease(pMem); 777 pMem->zMalloc = sqlite3DbMallocRawNN(db, 64); 778 if( db->mallocFailed ){ 779 pMem->flags = MEM_Null; 780 pMem->szMalloc = 0; 781 }else{ 782 assert( pMem->zMalloc ); 783 pMem->szMalloc = sqlite3DbMallocSize(db, pMem->zMalloc); 784 pMem->u.pRowSet = sqlite3RowSetInit(db, pMem->zMalloc, pMem->szMalloc); 785 assert( pMem->u.pRowSet!=0 ); 786 pMem->flags = MEM_RowSet; 787 } 788 } 789 790 /* 791 ** Return true if the Mem object contains a TEXT or BLOB that is 792 ** too large - whose size exceeds SQLITE_MAX_LENGTH. 793 */ 794 int sqlite3VdbeMemTooBig(Mem *p){ 795 assert( p->db!=0 ); 796 if( p->flags & (MEM_Str|MEM_Blob) ){ 797 int n = p->n; 798 if( p->flags & MEM_Zero ){ 799 n += p->u.nZero; 800 } 801 return n>p->db->aLimit[SQLITE_LIMIT_LENGTH]; 802 } 803 return 0; 804 } 805 806 #ifdef SQLITE_DEBUG 807 /* 808 ** This routine prepares a memory cell for modification by breaking 809 ** its link to a shallow copy and by marking any current shallow 810 ** copies of this cell as invalid. 811 ** 812 ** This is used for testing and debugging only - to make sure shallow 813 ** copies are not misused. 814 */ 815 void sqlite3VdbeMemAboutToChange(Vdbe *pVdbe, Mem *pMem){ 816 int i; 817 Mem *pX; 818 for(i=0, pX=pVdbe->aMem; i<pVdbe->nMem; i++, pX++){ 819 if( pX->pScopyFrom==pMem ){ 820 pX->flags |= MEM_Undefined; 821 pX->pScopyFrom = 0; 822 } 823 } 824 pMem->pScopyFrom = 0; 825 } 826 #endif /* SQLITE_DEBUG */ 827 828 829 /* 830 ** Make an shallow copy of pFrom into pTo. Prior contents of 831 ** pTo are freed. The pFrom->z field is not duplicated. If 832 ** pFrom->z is used, then pTo->z points to the same thing as pFrom->z 833 ** and flags gets srcType (either MEM_Ephem or MEM_Static). 834 */ 835 static SQLITE_NOINLINE void vdbeClrCopy(Mem *pTo, const Mem *pFrom, int eType){ 836 vdbeMemClearExternAndSetNull(pTo); 837 assert( !VdbeMemDynamic(pTo) ); 838 sqlite3VdbeMemShallowCopy(pTo, pFrom, eType); 839 } 840 void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){ 841 assert( (pFrom->flags & MEM_RowSet)==0 ); 842 assert( pTo->db==pFrom->db ); 843 if( VdbeMemDynamic(pTo) ){ vdbeClrCopy(pTo,pFrom,srcType); return; } 844 memcpy(pTo, pFrom, MEMCELLSIZE); 845 if( (pFrom->flags&MEM_Static)==0 ){ 846 pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Ephem); 847 assert( srcType==MEM_Ephem || srcType==MEM_Static ); 848 pTo->flags |= srcType; 849 } 850 } 851 852 /* 853 ** Make a full copy of pFrom into pTo. Prior contents of pTo are 854 ** freed before the copy is made. 855 */ 856 int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){ 857 int rc = SQLITE_OK; 858 859 assert( (pFrom->flags & MEM_RowSet)==0 ); 860 if( VdbeMemDynamic(pTo) ) vdbeMemClearExternAndSetNull(pTo); 861 memcpy(pTo, pFrom, MEMCELLSIZE); 862 pTo->flags &= ~MEM_Dyn; 863 if( pTo->flags&(MEM_Str|MEM_Blob) ){ 864 if( 0==(pFrom->flags&MEM_Static) ){ 865 pTo->flags |= MEM_Ephem; 866 rc = sqlite3VdbeMemMakeWriteable(pTo); 867 } 868 } 869 870 return rc; 871 } 872 873 /* 874 ** Transfer the contents of pFrom to pTo. Any existing value in pTo is 875 ** freed. If pFrom contains ephemeral data, a copy is made. 876 ** 877 ** pFrom contains an SQL NULL when this routine returns. 878 */ 879 void sqlite3VdbeMemMove(Mem *pTo, Mem *pFrom){ 880 assert( pFrom->db==0 || sqlite3_mutex_held(pFrom->db->mutex) ); 881 assert( pTo->db==0 || sqlite3_mutex_held(pTo->db->mutex) ); 882 assert( pFrom->db==0 || pTo->db==0 || pFrom->db==pTo->db ); 883 884 sqlite3VdbeMemRelease(pTo); 885 memcpy(pTo, pFrom, sizeof(Mem)); 886 pFrom->flags = MEM_Null; 887 pFrom->szMalloc = 0; 888 } 889 890 /* 891 ** Change the value of a Mem to be a string or a BLOB. 892 ** 893 ** The memory management strategy depends on the value of the xDel 894 ** parameter. If the value passed is SQLITE_TRANSIENT, then the 895 ** string is copied into a (possibly existing) buffer managed by the 896 ** Mem structure. Otherwise, any existing buffer is freed and the 897 ** pointer copied. 898 ** 899 ** If the string is too large (if it exceeds the SQLITE_LIMIT_LENGTH 900 ** size limit) then no memory allocation occurs. If the string can be 901 ** stored without allocating memory, then it is. If a memory allocation 902 ** is required to store the string, then value of pMem is unchanged. In 903 ** either case, SQLITE_TOOBIG is returned. 904 */ 905 int sqlite3VdbeMemSetStr( 906 Mem *pMem, /* Memory cell to set to string value */ 907 const char *z, /* String pointer */ 908 int n, /* Bytes in string, or negative */ 909 u8 enc, /* Encoding of z. 0 for BLOBs */ 910 void (*xDel)(void*) /* Destructor function */ 911 ){ 912 int nByte = n; /* New value for pMem->n */ 913 int iLimit; /* Maximum allowed string or blob size */ 914 u16 flags = 0; /* New value for pMem->flags */ 915 916 assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) ); 917 assert( (pMem->flags & MEM_RowSet)==0 ); 918 919 /* If z is a NULL pointer, set pMem to contain an SQL NULL. */ 920 if( !z ){ 921 sqlite3VdbeMemSetNull(pMem); 922 return SQLITE_OK; 923 } 924 925 if( pMem->db ){ 926 iLimit = pMem->db->aLimit[SQLITE_LIMIT_LENGTH]; 927 }else{ 928 iLimit = SQLITE_MAX_LENGTH; 929 } 930 flags = (enc==0?MEM_Blob:MEM_Str); 931 if( nByte<0 ){ 932 assert( enc!=0 ); 933 if( enc==SQLITE_UTF8 ){ 934 nByte = 0x7fffffff & (int)strlen(z); 935 if( nByte>iLimit ) nByte = iLimit+1; 936 }else{ 937 for(nByte=0; nByte<=iLimit && (z[nByte] | z[nByte+1]); nByte+=2){} 938 } 939 flags |= MEM_Term; 940 } 941 942 /* The following block sets the new values of Mem.z and Mem.xDel. It 943 ** also sets a flag in local variable "flags" to indicate the memory 944 ** management (one of MEM_Dyn or MEM_Static). 945 */ 946 if( xDel==SQLITE_TRANSIENT ){ 947 int nAlloc = nByte; 948 if( flags&MEM_Term ){ 949 nAlloc += (enc==SQLITE_UTF8?1:2); 950 } 951 if( nByte>iLimit ){ 952 return SQLITE_TOOBIG; 953 } 954 testcase( nAlloc==0 ); 955 testcase( nAlloc==31 ); 956 testcase( nAlloc==32 ); 957 if( sqlite3VdbeMemClearAndResize(pMem, MAX(nAlloc,32)) ){ 958 return SQLITE_NOMEM_BKPT; 959 } 960 memcpy(pMem->z, z, nAlloc); 961 }else if( xDel==SQLITE_DYNAMIC ){ 962 sqlite3VdbeMemRelease(pMem); 963 pMem->zMalloc = pMem->z = (char *)z; 964 pMem->szMalloc = sqlite3DbMallocSize(pMem->db, pMem->zMalloc); 965 }else{ 966 sqlite3VdbeMemRelease(pMem); 967 pMem->z = (char *)z; 968 pMem->xDel = xDel; 969 flags |= ((xDel==SQLITE_STATIC)?MEM_Static:MEM_Dyn); 970 } 971 972 pMem->n = nByte; 973 pMem->flags = flags; 974 pMem->enc = (enc==0 ? SQLITE_UTF8 : enc); 975 976 #ifndef SQLITE_OMIT_UTF16 977 if( pMem->enc!=SQLITE_UTF8 && sqlite3VdbeMemHandleBom(pMem) ){ 978 return SQLITE_NOMEM_BKPT; 979 } 980 #endif 981 982 if( nByte>iLimit ){ 983 return SQLITE_TOOBIG; 984 } 985 986 return SQLITE_OK; 987 } 988 989 /* 990 ** Move data out of a btree key or data field and into a Mem structure. 991 ** The data is payload from the entry that pCur is currently pointing 992 ** to. offset and amt determine what portion of the data or key to retrieve. 993 ** The result is written into the pMem element. 994 ** 995 ** The pMem object must have been initialized. This routine will use 996 ** pMem->zMalloc to hold the content from the btree, if possible. New 997 ** pMem->zMalloc space will be allocated if necessary. The calling routine 998 ** is responsible for making sure that the pMem object is eventually 999 ** destroyed. 1000 ** 1001 ** If this routine fails for any reason (malloc returns NULL or unable 1002 ** to read from the disk) then the pMem is left in an inconsistent state. 1003 */ 1004 static SQLITE_NOINLINE int vdbeMemFromBtreeResize( 1005 BtCursor *pCur, /* Cursor pointing at record to retrieve. */ 1006 u32 offset, /* Offset from the start of data to return bytes from. */ 1007 u32 amt, /* Number of bytes to return. */ 1008 Mem *pMem /* OUT: Return data in this Mem structure. */ 1009 ){ 1010 int rc; 1011 pMem->flags = MEM_Null; 1012 if( SQLITE_OK==(rc = sqlite3VdbeMemClearAndResize(pMem, amt+2)) ){ 1013 rc = sqlite3BtreePayload(pCur, offset, amt, pMem->z); 1014 if( rc==SQLITE_OK ){ 1015 pMem->z[amt] = 0; 1016 pMem->z[amt+1] = 0; 1017 pMem->flags = MEM_Blob|MEM_Term; 1018 pMem->n = (int)amt; 1019 }else{ 1020 sqlite3VdbeMemRelease(pMem); 1021 } 1022 } 1023 return rc; 1024 } 1025 int sqlite3VdbeMemFromBtree( 1026 BtCursor *pCur, /* Cursor pointing at record to retrieve. */ 1027 u32 offset, /* Offset from the start of data to return bytes from. */ 1028 u32 amt, /* Number of bytes to return. */ 1029 Mem *pMem /* OUT: Return data in this Mem structure. */ 1030 ){ 1031 char *zData; /* Data from the btree layer */ 1032 u32 available = 0; /* Number of bytes available on the local btree page */ 1033 int rc = SQLITE_OK; /* Return code */ 1034 1035 assert( sqlite3BtreeCursorIsValid(pCur) ); 1036 assert( !VdbeMemDynamic(pMem) ); 1037 1038 /* Note: the calls to BtreeKeyFetch() and DataFetch() below assert() 1039 ** that both the BtShared and database handle mutexes are held. */ 1040 assert( (pMem->flags & MEM_RowSet)==0 ); 1041 zData = (char *)sqlite3BtreePayloadFetch(pCur, &available); 1042 assert( zData!=0 ); 1043 1044 if( offset+amt<=available ){ 1045 pMem->z = &zData[offset]; 1046 pMem->flags = MEM_Blob|MEM_Ephem; 1047 pMem->n = (int)amt; 1048 }else{ 1049 rc = vdbeMemFromBtreeResize(pCur, offset, amt, pMem); 1050 } 1051 1052 return rc; 1053 } 1054 1055 /* 1056 ** The pVal argument is known to be a value other than NULL. 1057 ** Convert it into a string with encoding enc and return a pointer 1058 ** to a zero-terminated version of that string. 1059 */ 1060 static SQLITE_NOINLINE const void *valueToText(sqlite3_value* pVal, u8 enc){ 1061 assert( pVal!=0 ); 1062 assert( pVal->db==0 || sqlite3_mutex_held(pVal->db->mutex) ); 1063 assert( (enc&3)==(enc&~SQLITE_UTF16_ALIGNED) ); 1064 assert( (pVal->flags & MEM_RowSet)==0 ); 1065 assert( (pVal->flags & (MEM_Null))==0 ); 1066 if( pVal->flags & (MEM_Blob|MEM_Str) ){ 1067 if( ExpandBlob(pVal) ) return 0; 1068 pVal->flags |= MEM_Str; 1069 if( pVal->enc != (enc & ~SQLITE_UTF16_ALIGNED) ){ 1070 sqlite3VdbeChangeEncoding(pVal, enc & ~SQLITE_UTF16_ALIGNED); 1071 } 1072 if( (enc & SQLITE_UTF16_ALIGNED)!=0 && 1==(1&SQLITE_PTR_TO_INT(pVal->z)) ){ 1073 assert( (pVal->flags & (MEM_Ephem|MEM_Static))!=0 ); 1074 if( sqlite3VdbeMemMakeWriteable(pVal)!=SQLITE_OK ){ 1075 return 0; 1076 } 1077 } 1078 sqlite3VdbeMemNulTerminate(pVal); /* IMP: R-31275-44060 */ 1079 }else{ 1080 sqlite3VdbeMemStringify(pVal, enc, 0); 1081 assert( 0==(1&SQLITE_PTR_TO_INT(pVal->z)) ); 1082 } 1083 assert(pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) || pVal->db==0 1084 || pVal->db->mallocFailed ); 1085 if( pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) ){ 1086 return pVal->z; 1087 }else{ 1088 return 0; 1089 } 1090 } 1091 1092 /* This function is only available internally, it is not part of the 1093 ** external API. It works in a similar way to sqlite3_value_text(), 1094 ** except the data returned is in the encoding specified by the second 1095 ** parameter, which must be one of SQLITE_UTF16BE, SQLITE_UTF16LE or 1096 ** SQLITE_UTF8. 1097 ** 1098 ** (2006-02-16:) The enc value can be or-ed with SQLITE_UTF16_ALIGNED. 1099 ** If that is the case, then the result must be aligned on an even byte 1100 ** boundary. 1101 */ 1102 const void *sqlite3ValueText(sqlite3_value* pVal, u8 enc){ 1103 if( !pVal ) return 0; 1104 assert( pVal->db==0 || sqlite3_mutex_held(pVal->db->mutex) ); 1105 assert( (enc&3)==(enc&~SQLITE_UTF16_ALIGNED) ); 1106 assert( (pVal->flags & MEM_RowSet)==0 ); 1107 if( (pVal->flags&(MEM_Str|MEM_Term))==(MEM_Str|MEM_Term) && pVal->enc==enc ){ 1108 return pVal->z; 1109 } 1110 if( pVal->flags&MEM_Null ){ 1111 return 0; 1112 } 1113 return valueToText(pVal, enc); 1114 } 1115 1116 /* 1117 ** Create a new sqlite3_value object. 1118 */ 1119 sqlite3_value *sqlite3ValueNew(sqlite3 *db){ 1120 Mem *p = sqlite3DbMallocZero(db, sizeof(*p)); 1121 if( p ){ 1122 p->flags = MEM_Null; 1123 p->db = db; 1124 } 1125 return p; 1126 } 1127 1128 /* 1129 ** Context object passed by sqlite3Stat4ProbeSetValue() through to 1130 ** valueNew(). See comments above valueNew() for details. 1131 */ 1132 struct ValueNewStat4Ctx { 1133 Parse *pParse; 1134 Index *pIdx; 1135 UnpackedRecord **ppRec; 1136 int iVal; 1137 }; 1138 1139 /* 1140 ** Allocate and return a pointer to a new sqlite3_value object. If 1141 ** the second argument to this function is NULL, the object is allocated 1142 ** by calling sqlite3ValueNew(). 1143 ** 1144 ** Otherwise, if the second argument is non-zero, then this function is 1145 ** being called indirectly by sqlite3Stat4ProbeSetValue(). If it has not 1146 ** already been allocated, allocate the UnpackedRecord structure that 1147 ** that function will return to its caller here. Then return a pointer to 1148 ** an sqlite3_value within the UnpackedRecord.a[] array. 1149 */ 1150 static sqlite3_value *valueNew(sqlite3 *db, struct ValueNewStat4Ctx *p){ 1151 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4 1152 if( p ){ 1153 UnpackedRecord *pRec = p->ppRec[0]; 1154 1155 if( pRec==0 ){ 1156 Index *pIdx = p->pIdx; /* Index being probed */ 1157 int nByte; /* Bytes of space to allocate */ 1158 int i; /* Counter variable */ 1159 int nCol = pIdx->nColumn; /* Number of index columns including rowid */ 1160 1161 nByte = sizeof(Mem) * nCol + ROUND8(sizeof(UnpackedRecord)); 1162 pRec = (UnpackedRecord*)sqlite3DbMallocZero(db, nByte); 1163 if( pRec ){ 1164 pRec->pKeyInfo = sqlite3KeyInfoOfIndex(p->pParse, pIdx); 1165 if( pRec->pKeyInfo ){ 1166 assert( pRec->pKeyInfo->nAllField==nCol ); 1167 assert( pRec->pKeyInfo->enc==ENC(db) ); 1168 pRec->aMem = (Mem *)((u8*)pRec + ROUND8(sizeof(UnpackedRecord))); 1169 for(i=0; i<nCol; i++){ 1170 pRec->aMem[i].flags = MEM_Null; 1171 pRec->aMem[i].db = db; 1172 } 1173 }else{ 1174 sqlite3DbFreeNN(db, pRec); 1175 pRec = 0; 1176 } 1177 } 1178 if( pRec==0 ) return 0; 1179 p->ppRec[0] = pRec; 1180 } 1181 1182 pRec->nField = p->iVal+1; 1183 return &pRec->aMem[p->iVal]; 1184 } 1185 #else 1186 UNUSED_PARAMETER(p); 1187 #endif /* defined(SQLITE_ENABLE_STAT3_OR_STAT4) */ 1188 return sqlite3ValueNew(db); 1189 } 1190 1191 /* 1192 ** The expression object indicated by the second argument is guaranteed 1193 ** to be a scalar SQL function. If 1194 ** 1195 ** * all function arguments are SQL literals, 1196 ** * one of the SQLITE_FUNC_CONSTANT or _SLOCHNG function flags is set, and 1197 ** * the SQLITE_FUNC_NEEDCOLL function flag is not set, 1198 ** 1199 ** then this routine attempts to invoke the SQL function. Assuming no 1200 ** error occurs, output parameter (*ppVal) is set to point to a value 1201 ** object containing the result before returning SQLITE_OK. 1202 ** 1203 ** Affinity aff is applied to the result of the function before returning. 1204 ** If the result is a text value, the sqlite3_value object uses encoding 1205 ** enc. 1206 ** 1207 ** If the conditions above are not met, this function returns SQLITE_OK 1208 ** and sets (*ppVal) to NULL. Or, if an error occurs, (*ppVal) is set to 1209 ** NULL and an SQLite error code returned. 1210 */ 1211 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4 1212 static int valueFromFunction( 1213 sqlite3 *db, /* The database connection */ 1214 Expr *p, /* The expression to evaluate */ 1215 u8 enc, /* Encoding to use */ 1216 u8 aff, /* Affinity to use */ 1217 sqlite3_value **ppVal, /* Write the new value here */ 1218 struct ValueNewStat4Ctx *pCtx /* Second argument for valueNew() */ 1219 ){ 1220 sqlite3_context ctx; /* Context object for function invocation */ 1221 sqlite3_value **apVal = 0; /* Function arguments */ 1222 int nVal = 0; /* Size of apVal[] array */ 1223 FuncDef *pFunc = 0; /* Function definition */ 1224 sqlite3_value *pVal = 0; /* New value */ 1225 int rc = SQLITE_OK; /* Return code */ 1226 ExprList *pList = 0; /* Function arguments */ 1227 int i; /* Iterator variable */ 1228 1229 assert( pCtx!=0 ); 1230 assert( (p->flags & EP_TokenOnly)==0 ); 1231 pList = p->x.pList; 1232 if( pList ) nVal = pList->nExpr; 1233 pFunc = sqlite3FindFunction(db, p->u.zToken, nVal, enc, 0); 1234 assert( pFunc ); 1235 if( (pFunc->funcFlags & (SQLITE_FUNC_CONSTANT|SQLITE_FUNC_SLOCHNG))==0 1236 || (pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL) 1237 ){ 1238 return SQLITE_OK; 1239 } 1240 1241 if( pList ){ 1242 apVal = (sqlite3_value**)sqlite3DbMallocZero(db, sizeof(apVal[0]) * nVal); 1243 if( apVal==0 ){ 1244 rc = SQLITE_NOMEM_BKPT; 1245 goto value_from_function_out; 1246 } 1247 for(i=0; i<nVal; i++){ 1248 rc = sqlite3ValueFromExpr(db, pList->a[i].pExpr, enc, aff, &apVal[i]); 1249 if( apVal[i]==0 || rc!=SQLITE_OK ) goto value_from_function_out; 1250 } 1251 } 1252 1253 pVal = valueNew(db, pCtx); 1254 if( pVal==0 ){ 1255 rc = SQLITE_NOMEM_BKPT; 1256 goto value_from_function_out; 1257 } 1258 1259 assert( pCtx->pParse->rc==SQLITE_OK ); 1260 memset(&ctx, 0, sizeof(ctx)); 1261 ctx.pOut = pVal; 1262 ctx.pFunc = pFunc; 1263 pFunc->xSFunc(&ctx, nVal, apVal); 1264 if( ctx.isError ){ 1265 rc = ctx.isError; 1266 sqlite3ErrorMsg(pCtx->pParse, "%s", sqlite3_value_text(pVal)); 1267 }else{ 1268 sqlite3ValueApplyAffinity(pVal, aff, SQLITE_UTF8); 1269 assert( rc==SQLITE_OK ); 1270 rc = sqlite3VdbeChangeEncoding(pVal, enc); 1271 if( rc==SQLITE_OK && sqlite3VdbeMemTooBig(pVal) ){ 1272 rc = SQLITE_TOOBIG; 1273 pCtx->pParse->nErr++; 1274 } 1275 } 1276 pCtx->pParse->rc = rc; 1277 1278 value_from_function_out: 1279 if( rc!=SQLITE_OK ){ 1280 pVal = 0; 1281 } 1282 if( apVal ){ 1283 for(i=0; i<nVal; i++){ 1284 sqlite3ValueFree(apVal[i]); 1285 } 1286 sqlite3DbFreeNN(db, apVal); 1287 } 1288 1289 *ppVal = pVal; 1290 return rc; 1291 } 1292 #else 1293 # define valueFromFunction(a,b,c,d,e,f) SQLITE_OK 1294 #endif /* defined(SQLITE_ENABLE_STAT3_OR_STAT4) */ 1295 1296 /* 1297 ** Extract a value from the supplied expression in the manner described 1298 ** above sqlite3ValueFromExpr(). Allocate the sqlite3_value object 1299 ** using valueNew(). 1300 ** 1301 ** If pCtx is NULL and an error occurs after the sqlite3_value object 1302 ** has been allocated, it is freed before returning. Or, if pCtx is not 1303 ** NULL, it is assumed that the caller will free any allocated object 1304 ** in all cases. 1305 */ 1306 static int valueFromExpr( 1307 sqlite3 *db, /* The database connection */ 1308 Expr *pExpr, /* The expression to evaluate */ 1309 u8 enc, /* Encoding to use */ 1310 u8 affinity, /* Affinity to use */ 1311 sqlite3_value **ppVal, /* Write the new value here */ 1312 struct ValueNewStat4Ctx *pCtx /* Second argument for valueNew() */ 1313 ){ 1314 int op; 1315 char *zVal = 0; 1316 sqlite3_value *pVal = 0; 1317 int negInt = 1; 1318 const char *zNeg = ""; 1319 int rc = SQLITE_OK; 1320 1321 assert( pExpr!=0 ); 1322 while( (op = pExpr->op)==TK_UPLUS || op==TK_SPAN ) pExpr = pExpr->pLeft; 1323 if( NEVER(op==TK_REGISTER) ) op = pExpr->op2; 1324 1325 /* Compressed expressions only appear when parsing the DEFAULT clause 1326 ** on a table column definition, and hence only when pCtx==0. This 1327 ** check ensures that an EP_TokenOnly expression is never passed down 1328 ** into valueFromFunction(). */ 1329 assert( (pExpr->flags & EP_TokenOnly)==0 || pCtx==0 ); 1330 1331 if( op==TK_CAST ){ 1332 u8 aff = sqlite3AffinityType(pExpr->u.zToken,0); 1333 rc = valueFromExpr(db, pExpr->pLeft, enc, aff, ppVal, pCtx); 1334 testcase( rc!=SQLITE_OK ); 1335 if( *ppVal ){ 1336 sqlite3VdbeMemCast(*ppVal, aff, SQLITE_UTF8); 1337 sqlite3ValueApplyAffinity(*ppVal, affinity, SQLITE_UTF8); 1338 } 1339 return rc; 1340 } 1341 1342 /* Handle negative integers in a single step. This is needed in the 1343 ** case when the value is -9223372036854775808. 1344 */ 1345 if( op==TK_UMINUS 1346 && (pExpr->pLeft->op==TK_INTEGER || pExpr->pLeft->op==TK_FLOAT) ){ 1347 pExpr = pExpr->pLeft; 1348 op = pExpr->op; 1349 negInt = -1; 1350 zNeg = "-"; 1351 } 1352 1353 if( op==TK_STRING || op==TK_FLOAT || op==TK_INTEGER ){ 1354 pVal = valueNew(db, pCtx); 1355 if( pVal==0 ) goto no_mem; 1356 if( ExprHasProperty(pExpr, EP_IntValue) ){ 1357 sqlite3VdbeMemSetInt64(pVal, (i64)pExpr->u.iValue*negInt); 1358 }else{ 1359 zVal = sqlite3MPrintf(db, "%s%s", zNeg, pExpr->u.zToken); 1360 if( zVal==0 ) goto no_mem; 1361 sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, SQLITE_DYNAMIC); 1362 } 1363 if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_BLOB ){ 1364 sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, SQLITE_UTF8); 1365 }else{ 1366 sqlite3ValueApplyAffinity(pVal, affinity, SQLITE_UTF8); 1367 } 1368 if( pVal->flags & (MEM_Int|MEM_Real) ) pVal->flags &= ~MEM_Str; 1369 if( enc!=SQLITE_UTF8 ){ 1370 rc = sqlite3VdbeChangeEncoding(pVal, enc); 1371 } 1372 }else if( op==TK_UMINUS ) { 1373 /* This branch happens for multiple negative signs. Ex: -(-5) */ 1374 if( SQLITE_OK==valueFromExpr(db,pExpr->pLeft,enc,affinity,&pVal,pCtx) 1375 && pVal!=0 1376 ){ 1377 sqlite3VdbeMemNumerify(pVal); 1378 if( pVal->flags & MEM_Real ){ 1379 pVal->u.r = -pVal->u.r; 1380 }else if( pVal->u.i==SMALLEST_INT64 ){ 1381 pVal->u.r = -(double)SMALLEST_INT64; 1382 MemSetTypeFlag(pVal, MEM_Real); 1383 }else{ 1384 pVal->u.i = -pVal->u.i; 1385 } 1386 sqlite3ValueApplyAffinity(pVal, affinity, enc); 1387 } 1388 }else if( op==TK_NULL ){ 1389 pVal = valueNew(db, pCtx); 1390 if( pVal==0 ) goto no_mem; 1391 sqlite3VdbeMemNumerify(pVal); 1392 } 1393 #ifndef SQLITE_OMIT_BLOB_LITERAL 1394 else if( op==TK_BLOB ){ 1395 int nVal; 1396 assert( pExpr->u.zToken[0]=='x' || pExpr->u.zToken[0]=='X' ); 1397 assert( pExpr->u.zToken[1]=='\'' ); 1398 pVal = valueNew(db, pCtx); 1399 if( !pVal ) goto no_mem; 1400 zVal = &pExpr->u.zToken[2]; 1401 nVal = sqlite3Strlen30(zVal)-1; 1402 assert( zVal[nVal]=='\'' ); 1403 sqlite3VdbeMemSetStr(pVal, sqlite3HexToBlob(db, zVal, nVal), nVal/2, 1404 0, SQLITE_DYNAMIC); 1405 } 1406 #endif 1407 1408 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4 1409 else if( op==TK_FUNCTION && pCtx!=0 ){ 1410 rc = valueFromFunction(db, pExpr, enc, affinity, &pVal, pCtx); 1411 } 1412 #endif 1413 1414 *ppVal = pVal; 1415 return rc; 1416 1417 no_mem: 1418 sqlite3OomFault(db); 1419 sqlite3DbFree(db, zVal); 1420 assert( *ppVal==0 ); 1421 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4 1422 if( pCtx==0 ) sqlite3ValueFree(pVal); 1423 #else 1424 assert( pCtx==0 ); sqlite3ValueFree(pVal); 1425 #endif 1426 return SQLITE_NOMEM_BKPT; 1427 } 1428 1429 /* 1430 ** Create a new sqlite3_value object, containing the value of pExpr. 1431 ** 1432 ** This only works for very simple expressions that consist of one constant 1433 ** token (i.e. "5", "5.1", "'a string'"). If the expression can 1434 ** be converted directly into a value, then the value is allocated and 1435 ** a pointer written to *ppVal. The caller is responsible for deallocating 1436 ** the value by passing it to sqlite3ValueFree() later on. If the expression 1437 ** cannot be converted to a value, then *ppVal is set to NULL. 1438 */ 1439 int sqlite3ValueFromExpr( 1440 sqlite3 *db, /* The database connection */ 1441 Expr *pExpr, /* The expression to evaluate */ 1442 u8 enc, /* Encoding to use */ 1443 u8 affinity, /* Affinity to use */ 1444 sqlite3_value **ppVal /* Write the new value here */ 1445 ){ 1446 return pExpr ? valueFromExpr(db, pExpr, enc, affinity, ppVal, 0) : 0; 1447 } 1448 1449 #ifdef SQLITE_ENABLE_STAT3_OR_STAT4 1450 /* 1451 ** The implementation of the sqlite_record() function. This function accepts 1452 ** a single argument of any type. The return value is a formatted database 1453 ** record (a blob) containing the argument value. 1454 ** 1455 ** This is used to convert the value stored in the 'sample' column of the 1456 ** sqlite_stat3 table to the record format SQLite uses internally. 1457 */ 1458 static void recordFunc( 1459 sqlite3_context *context, 1460 int argc, 1461 sqlite3_value **argv 1462 ){ 1463 const int file_format = 1; 1464 u32 iSerial; /* Serial type */ 1465 int nSerial; /* Bytes of space for iSerial as varint */ 1466 u32 nVal; /* Bytes of space required for argv[0] */ 1467 int nRet; 1468 sqlite3 *db; 1469 u8 *aRet; 1470 1471 UNUSED_PARAMETER( argc ); 1472 iSerial = sqlite3VdbeSerialType(argv[0], file_format, &nVal); 1473 nSerial = sqlite3VarintLen(iSerial); 1474 db = sqlite3_context_db_handle(context); 1475 1476 nRet = 1 + nSerial + nVal; 1477 aRet = sqlite3DbMallocRawNN(db, nRet); 1478 if( aRet==0 ){ 1479 sqlite3_result_error_nomem(context); 1480 }else{ 1481 aRet[0] = nSerial+1; 1482 putVarint32(&aRet[1], iSerial); 1483 sqlite3VdbeSerialPut(&aRet[1+nSerial], argv[0], iSerial); 1484 sqlite3_result_blob(context, aRet, nRet, SQLITE_TRANSIENT); 1485 sqlite3DbFreeNN(db, aRet); 1486 } 1487 } 1488 1489 /* 1490 ** Register built-in functions used to help read ANALYZE data. 1491 */ 1492 void sqlite3AnalyzeFunctions(void){ 1493 static FuncDef aAnalyzeTableFuncs[] = { 1494 FUNCTION(sqlite_record, 1, 0, 0, recordFunc), 1495 }; 1496 sqlite3InsertBuiltinFuncs(aAnalyzeTableFuncs, ArraySize(aAnalyzeTableFuncs)); 1497 } 1498 1499 /* 1500 ** Attempt to extract a value from pExpr and use it to construct *ppVal. 1501 ** 1502 ** If pAlloc is not NULL, then an UnpackedRecord object is created for 1503 ** pAlloc if one does not exist and the new value is added to the 1504 ** UnpackedRecord object. 1505 ** 1506 ** A value is extracted in the following cases: 1507 ** 1508 ** * (pExpr==0). In this case the value is assumed to be an SQL NULL, 1509 ** 1510 ** * The expression is a bound variable, and this is a reprepare, or 1511 ** 1512 ** * The expression is a literal value. 1513 ** 1514 ** On success, *ppVal is made to point to the extracted value. The caller 1515 ** is responsible for ensuring that the value is eventually freed. 1516 */ 1517 static int stat4ValueFromExpr( 1518 Parse *pParse, /* Parse context */ 1519 Expr *pExpr, /* The expression to extract a value from */ 1520 u8 affinity, /* Affinity to use */ 1521 struct ValueNewStat4Ctx *pAlloc,/* How to allocate space. Or NULL */ 1522 sqlite3_value **ppVal /* OUT: New value object (or NULL) */ 1523 ){ 1524 int rc = SQLITE_OK; 1525 sqlite3_value *pVal = 0; 1526 sqlite3 *db = pParse->db; 1527 1528 /* Skip over any TK_COLLATE nodes */ 1529 pExpr = sqlite3ExprSkipCollate(pExpr); 1530 1531 assert( pExpr==0 || pExpr->op!=TK_REGISTER || pExpr->op2!=TK_VARIABLE ); 1532 if( !pExpr ){ 1533 pVal = valueNew(db, pAlloc); 1534 if( pVal ){ 1535 sqlite3VdbeMemSetNull((Mem*)pVal); 1536 } 1537 }else if( pExpr->op==TK_VARIABLE && (db->flags & SQLITE_EnableQPSG)==0 ){ 1538 Vdbe *v; 1539 int iBindVar = pExpr->iColumn; 1540 sqlite3VdbeSetVarmask(pParse->pVdbe, iBindVar); 1541 if( (v = pParse->pReprepare)!=0 ){ 1542 pVal = valueNew(db, pAlloc); 1543 if( pVal ){ 1544 rc = sqlite3VdbeMemCopy((Mem*)pVal, &v->aVar[iBindVar-1]); 1545 sqlite3ValueApplyAffinity(pVal, affinity, ENC(db)); 1546 pVal->db = pParse->db; 1547 } 1548 } 1549 }else{ 1550 rc = valueFromExpr(db, pExpr, ENC(db), affinity, &pVal, pAlloc); 1551 } 1552 1553 assert( pVal==0 || pVal->db==db ); 1554 *ppVal = pVal; 1555 return rc; 1556 } 1557 1558 /* 1559 ** This function is used to allocate and populate UnpackedRecord 1560 ** structures intended to be compared against sample index keys stored 1561 ** in the sqlite_stat4 table. 1562 ** 1563 ** A single call to this function populates zero or more fields of the 1564 ** record starting with field iVal (fields are numbered from left to 1565 ** right starting with 0). A single field is populated if: 1566 ** 1567 ** * (pExpr==0). In this case the value is assumed to be an SQL NULL, 1568 ** 1569 ** * The expression is a bound variable, and this is a reprepare, or 1570 ** 1571 ** * The sqlite3ValueFromExpr() function is able to extract a value 1572 ** from the expression (i.e. the expression is a literal value). 1573 ** 1574 ** Or, if pExpr is a TK_VECTOR, one field is populated for each of the 1575 ** vector components that match either of the two latter criteria listed 1576 ** above. 1577 ** 1578 ** Before any value is appended to the record, the affinity of the 1579 ** corresponding column within index pIdx is applied to it. Before 1580 ** this function returns, output parameter *pnExtract is set to the 1581 ** number of values appended to the record. 1582 ** 1583 ** When this function is called, *ppRec must either point to an object 1584 ** allocated by an earlier call to this function, or must be NULL. If it 1585 ** is NULL and a value can be successfully extracted, a new UnpackedRecord 1586 ** is allocated (and *ppRec set to point to it) before returning. 1587 ** 1588 ** Unless an error is encountered, SQLITE_OK is returned. It is not an 1589 ** error if a value cannot be extracted from pExpr. If an error does 1590 ** occur, an SQLite error code is returned. 1591 */ 1592 int sqlite3Stat4ProbeSetValue( 1593 Parse *pParse, /* Parse context */ 1594 Index *pIdx, /* Index being probed */ 1595 UnpackedRecord **ppRec, /* IN/OUT: Probe record */ 1596 Expr *pExpr, /* The expression to extract a value from */ 1597 int nElem, /* Maximum number of values to append */ 1598 int iVal, /* Array element to populate */ 1599 int *pnExtract /* OUT: Values appended to the record */ 1600 ){ 1601 int rc = SQLITE_OK; 1602 int nExtract = 0; 1603 1604 if( pExpr==0 || pExpr->op!=TK_SELECT ){ 1605 int i; 1606 struct ValueNewStat4Ctx alloc; 1607 1608 alloc.pParse = pParse; 1609 alloc.pIdx = pIdx; 1610 alloc.ppRec = ppRec; 1611 1612 for(i=0; i<nElem; i++){ 1613 sqlite3_value *pVal = 0; 1614 Expr *pElem = (pExpr ? sqlite3VectorFieldSubexpr(pExpr, i) : 0); 1615 u8 aff = sqlite3IndexColumnAffinity(pParse->db, pIdx, iVal+i); 1616 alloc.iVal = iVal+i; 1617 rc = stat4ValueFromExpr(pParse, pElem, aff, &alloc, &pVal); 1618 if( !pVal ) break; 1619 nExtract++; 1620 } 1621 } 1622 1623 *pnExtract = nExtract; 1624 return rc; 1625 } 1626 1627 /* 1628 ** Attempt to extract a value from expression pExpr using the methods 1629 ** as described for sqlite3Stat4ProbeSetValue() above. 1630 ** 1631 ** If successful, set *ppVal to point to a new value object and return 1632 ** SQLITE_OK. If no value can be extracted, but no other error occurs 1633 ** (e.g. OOM), return SQLITE_OK and set *ppVal to NULL. Or, if an error 1634 ** does occur, return an SQLite error code. The final value of *ppVal 1635 ** is undefined in this case. 1636 */ 1637 int sqlite3Stat4ValueFromExpr( 1638 Parse *pParse, /* Parse context */ 1639 Expr *pExpr, /* The expression to extract a value from */ 1640 u8 affinity, /* Affinity to use */ 1641 sqlite3_value **ppVal /* OUT: New value object (or NULL) */ 1642 ){ 1643 return stat4ValueFromExpr(pParse, pExpr, affinity, 0, ppVal); 1644 } 1645 1646 /* 1647 ** Extract the iCol-th column from the nRec-byte record in pRec. Write 1648 ** the column value into *ppVal. If *ppVal is initially NULL then a new 1649 ** sqlite3_value object is allocated. 1650 ** 1651 ** If *ppVal is initially NULL then the caller is responsible for 1652 ** ensuring that the value written into *ppVal is eventually freed. 1653 */ 1654 int sqlite3Stat4Column( 1655 sqlite3 *db, /* Database handle */ 1656 const void *pRec, /* Pointer to buffer containing record */ 1657 int nRec, /* Size of buffer pRec in bytes */ 1658 int iCol, /* Column to extract */ 1659 sqlite3_value **ppVal /* OUT: Extracted value */ 1660 ){ 1661 u32 t; /* a column type code */ 1662 int nHdr; /* Size of the header in the record */ 1663 int iHdr; /* Next unread header byte */ 1664 int iField; /* Next unread data byte */ 1665 int szField; /* Size of the current data field */ 1666 int i; /* Column index */ 1667 u8 *a = (u8*)pRec; /* Typecast byte array */ 1668 Mem *pMem = *ppVal; /* Write result into this Mem object */ 1669 1670 assert( iCol>0 ); 1671 iHdr = getVarint32(a, nHdr); 1672 if( nHdr>nRec || iHdr>=nHdr ) return SQLITE_CORRUPT_BKPT; 1673 iField = nHdr; 1674 for(i=0; i<=iCol; i++){ 1675 iHdr += getVarint32(&a[iHdr], t); 1676 testcase( iHdr==nHdr ); 1677 testcase( iHdr==nHdr+1 ); 1678 if( iHdr>nHdr ) return SQLITE_CORRUPT_BKPT; 1679 szField = sqlite3VdbeSerialTypeLen(t); 1680 iField += szField; 1681 } 1682 testcase( iField==nRec ); 1683 testcase( iField==nRec+1 ); 1684 if( iField>nRec ) return SQLITE_CORRUPT_BKPT; 1685 if( pMem==0 ){ 1686 pMem = *ppVal = sqlite3ValueNew(db); 1687 if( pMem==0 ) return SQLITE_NOMEM_BKPT; 1688 } 1689 sqlite3VdbeSerialGet(&a[iField-szField], t, pMem); 1690 pMem->enc = ENC(db); 1691 return SQLITE_OK; 1692 } 1693 1694 /* 1695 ** Unless it is NULL, the argument must be an UnpackedRecord object returned 1696 ** by an earlier call to sqlite3Stat4ProbeSetValue(). This call deletes 1697 ** the object. 1698 */ 1699 void sqlite3Stat4ProbeFree(UnpackedRecord *pRec){ 1700 if( pRec ){ 1701 int i; 1702 int nCol = pRec->pKeyInfo->nAllField; 1703 Mem *aMem = pRec->aMem; 1704 sqlite3 *db = aMem[0].db; 1705 for(i=0; i<nCol; i++){ 1706 sqlite3VdbeMemRelease(&aMem[i]); 1707 } 1708 sqlite3KeyInfoUnref(pRec->pKeyInfo); 1709 sqlite3DbFreeNN(db, pRec); 1710 } 1711 } 1712 #endif /* ifdef SQLITE_ENABLE_STAT4 */ 1713 1714 /* 1715 ** Change the string value of an sqlite3_value object 1716 */ 1717 void sqlite3ValueSetStr( 1718 sqlite3_value *v, /* Value to be set */ 1719 int n, /* Length of string z */ 1720 const void *z, /* Text of the new string */ 1721 u8 enc, /* Encoding to use */ 1722 void (*xDel)(void*) /* Destructor for the string */ 1723 ){ 1724 if( v ) sqlite3VdbeMemSetStr((Mem *)v, z, n, enc, xDel); 1725 } 1726 1727 /* 1728 ** Free an sqlite3_value object 1729 */ 1730 void sqlite3ValueFree(sqlite3_value *v){ 1731 if( !v ) return; 1732 sqlite3VdbeMemRelease((Mem *)v); 1733 sqlite3DbFreeNN(((Mem*)v)->db, v); 1734 } 1735 1736 /* 1737 ** The sqlite3ValueBytes() routine returns the number of bytes in the 1738 ** sqlite3_value object assuming that it uses the encoding "enc". 1739 ** The valueBytes() routine is a helper function. 1740 */ 1741 static SQLITE_NOINLINE int valueBytes(sqlite3_value *pVal, u8 enc){ 1742 return valueToText(pVal, enc)!=0 ? pVal->n : 0; 1743 } 1744 int sqlite3ValueBytes(sqlite3_value *pVal, u8 enc){ 1745 Mem *p = (Mem*)pVal; 1746 assert( (p->flags & MEM_Null)==0 || (p->flags & (MEM_Str|MEM_Blob))==0 ); 1747 if( (p->flags & MEM_Str)!=0 && pVal->enc==enc ){ 1748 return p->n; 1749 } 1750 if( (p->flags & MEM_Blob)!=0 ){ 1751 if( p->flags & MEM_Zero ){ 1752 return p->n + p->u.nZero; 1753 }else{ 1754 return p->n; 1755 } 1756 } 1757 if( p->flags & MEM_Null ) return 0; 1758 return valueBytes(pVal, enc); 1759 }