1 /* 2 ** 2001 September 15 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 ** Utility functions used throughout sqlite. 13 ** 14 ** This file contains functions for allocating memory, comparing 15 ** strings, and stuff like that. 16 ** 17 */ 18 #include "sqliteInt.h" 19 #include <stdarg.h> 20 #include <math.h> 21 22 /* 23 ** Routine needed to support the testcase() macro. 24 */ 25 #ifdef SQLITE_COVERAGE_TEST 26 void sqlite3Coverage(int x){ 27 static unsigned dummy = 0; 28 dummy += (unsigned)x; 29 } 30 #endif 31 32 /* 33 ** Calls to sqlite3FaultSim() are used to simulate a failure during testing, 34 ** or to bypass normal error detection during testing in order to let 35 ** execute proceed futher downstream. 36 ** 37 ** In deployment, sqlite3FaultSim() *always* return SQLITE_OK (0). The 38 ** sqlite3FaultSim() function only returns non-zero during testing. 39 ** 40 ** During testing, if the test harness has set a fault-sim callback using 41 ** a call to sqlite3_test_control(SQLITE_TESTCTRL_FAULT_INSTALL), then 42 ** each call to sqlite3FaultSim() is relayed to that application-supplied 43 ** callback and the integer return value form the application-supplied 44 ** callback is returned by sqlite3FaultSim(). 45 ** 46 ** The integer argument to sqlite3FaultSim() is a code to identify which 47 ** sqlite3FaultSim() instance is being invoked. Each call to sqlite3FaultSim() 48 ** should have a unique code. To prevent legacy testing applications from 49 ** breaking, the codes should not be changed or reused. 50 */ 51 #ifndef SQLITE_UNTESTABLE 52 int sqlite3FaultSim(int iTest){ 53 int (*xCallback)(int) = sqlite3GlobalConfig.xTestCallback; 54 return xCallback ? xCallback(iTest) : SQLITE_OK; 55 } 56 #endif 57 58 #ifndef SQLITE_OMIT_FLOATING_POINT 59 /* 60 ** Return true if the floating point value is Not a Number (NaN). 61 */ 62 int sqlite3IsNaN(double x){ 63 u64 y; 64 memcpy(&y,&x,sizeof(y)); 65 return IsNaN(y); 66 } 67 #endif /* SQLITE_OMIT_FLOATING_POINT */ 68 69 /* 70 ** Compute a string length that is limited to what can be stored in 71 ** lower 30 bits of a 32-bit signed integer. 72 ** 73 ** The value returned will never be negative. Nor will it ever be greater 74 ** than the actual length of the string. For very long strings (greater 75 ** than 1GiB) the value returned might be less than the true string length. 76 */ 77 int sqlite3Strlen30(const char *z){ 78 if( z==0 ) return 0; 79 return 0x3fffffff & (int)strlen(z); 80 } 81 82 /* 83 ** Return the declared type of a column. Or return zDflt if the column 84 ** has no declared type. 85 ** 86 ** The column type is an extra string stored after the zero-terminator on 87 ** the column name if and only if the COLFLAG_HASTYPE flag is set. 88 */ 89 char *sqlite3ColumnType(Column *pCol, char *zDflt){ 90 if( (pCol->colFlags & COLFLAG_HASTYPE)==0 ) return zDflt; 91 return pCol->zName + strlen(pCol->zName) + 1; 92 } 93 94 /* 95 ** Helper function for sqlite3Error() - called rarely. Broken out into 96 ** a separate routine to avoid unnecessary register saves on entry to 97 ** sqlite3Error(). 98 */ 99 static SQLITE_NOINLINE void sqlite3ErrorFinish(sqlite3 *db, int err_code){ 100 if( db->pErr ) sqlite3ValueSetNull(db->pErr); 101 sqlite3SystemError(db, err_code); 102 } 103 104 /* 105 ** Set the current error code to err_code and clear any prior error message. 106 ** Also set iSysErrno (by calling sqlite3System) if the err_code indicates 107 ** that would be appropriate. 108 */ 109 void sqlite3Error(sqlite3 *db, int err_code){ 110 assert( db!=0 ); 111 db->errCode = err_code; 112 if( err_code || db->pErr ) sqlite3ErrorFinish(db, err_code); 113 } 114 115 /* 116 ** Load the sqlite3.iSysErrno field if that is an appropriate thing 117 ** to do based on the SQLite error code in rc. 118 */ 119 void sqlite3SystemError(sqlite3 *db, int rc){ 120 if( rc==SQLITE_IOERR_NOMEM ) return; 121 rc &= 0xff; 122 if( rc==SQLITE_CANTOPEN || rc==SQLITE_IOERR ){ 123 db->iSysErrno = sqlite3OsGetLastError(db->pVfs); 124 } 125 } 126 127 /* 128 ** Set the most recent error code and error string for the sqlite 129 ** handle "db". The error code is set to "err_code". 130 ** 131 ** If it is not NULL, string zFormat specifies the format of the 132 ** error string in the style of the printf functions: The following 133 ** format characters are allowed: 134 ** 135 ** %s Insert a string 136 ** %z A string that should be freed after use 137 ** %d Insert an integer 138 ** %T Insert a token 139 ** %S Insert the first element of a SrcList 140 ** 141 ** zFormat and any string tokens that follow it are assumed to be 142 ** encoded in UTF-8. 143 ** 144 ** To clear the most recent error for sqlite handle "db", sqlite3Error 145 ** should be called with err_code set to SQLITE_OK and zFormat set 146 ** to NULL. 147 */ 148 void sqlite3ErrorWithMsg(sqlite3 *db, int err_code, const char *zFormat, ...){ 149 assert( db!=0 ); 150 db->errCode = err_code; 151 sqlite3SystemError(db, err_code); 152 if( zFormat==0 ){ 153 sqlite3Error(db, err_code); 154 }else if( db->pErr || (db->pErr = sqlite3ValueNew(db))!=0 ){ 155 char *z; 156 va_list ap; 157 va_start(ap, zFormat); 158 z = sqlite3VMPrintf(db, zFormat, ap); 159 va_end(ap); 160 sqlite3ValueSetStr(db->pErr, -1, z, SQLITE_UTF8, SQLITE_DYNAMIC); 161 } 162 } 163 164 /* 165 ** Add an error message to pParse->zErrMsg and increment pParse->nErr. 166 ** The following formatting characters are allowed: 167 ** 168 ** %s Insert a string 169 ** %z A string that should be freed after use 170 ** %d Insert an integer 171 ** %T Insert a token 172 ** %S Insert the first element of a SrcList 173 ** 174 ** This function should be used to report any error that occurs while 175 ** compiling an SQL statement (i.e. within sqlite3_prepare()). The 176 ** last thing the sqlite3_prepare() function does is copy the error 177 ** stored by this function into the database handle using sqlite3Error(). 178 ** Functions sqlite3Error() or sqlite3ErrorWithMsg() should be used 179 ** during statement execution (sqlite3_step() etc.). 180 */ 181 void sqlite3ErrorMsg(Parse *pParse, const char *zFormat, ...){ 182 char *zMsg; 183 va_list ap; 184 sqlite3 *db = pParse->db; 185 va_start(ap, zFormat); 186 zMsg = sqlite3VMPrintf(db, zFormat, ap); 187 va_end(ap); 188 if( db->suppressErr ){ 189 sqlite3DbFree(db, zMsg); 190 }else{ 191 pParse->nErr++; 192 sqlite3DbFree(db, pParse->zErrMsg); 193 pParse->zErrMsg = zMsg; 194 pParse->rc = SQLITE_ERROR; 195 } 196 } 197 198 /* 199 ** If database connection db is currently parsing SQL, then transfer 200 ** error code errCode to that parser if the parser has not already 201 ** encountered some other kind of error. 202 */ 203 int sqlite3ErrorToParser(sqlite3 *db, int errCode){ 204 Parse *pParse; 205 if( db==0 || (pParse = db->pParse)==0 ) return errCode; 206 pParse->rc = errCode; 207 pParse->nErr++; 208 return errCode; 209 } 210 211 /* 212 ** Convert an SQL-style quoted string into a normal string by removing 213 ** the quote characters. The conversion is done in-place. If the 214 ** input does not begin with a quote character, then this routine 215 ** is a no-op. 216 ** 217 ** The input string must be zero-terminated. A new zero-terminator 218 ** is added to the dequoted string. 219 ** 220 ** The return value is -1 if no dequoting occurs or the length of the 221 ** dequoted string, exclusive of the zero terminator, if dequoting does 222 ** occur. 223 ** 224 ** 2002-02-14: This routine is extended to remove MS-Access style 225 ** brackets from around identifiers. For example: "[a-b-c]" becomes 226 ** "a-b-c". 227 */ 228 void sqlite3Dequote(char *z){ 229 char quote; 230 int i, j; 231 if( z==0 ) return; 232 quote = z[0]; 233 if( !sqlite3Isquote(quote) ) return; 234 if( quote=='[' ) quote = ']'; 235 for(i=1, j=0;; i++){ 236 assert( z[i] ); 237 if( z[i]==quote ){ 238 if( z[i+1]==quote ){ 239 z[j++] = quote; 240 i++; 241 }else{ 242 break; 243 } 244 }else{ 245 z[j++] = z[i]; 246 } 247 } 248 z[j] = 0; 249 } 250 void sqlite3DequoteExpr(Expr *p){ 251 assert( sqlite3Isquote(p->u.zToken[0]) ); 252 p->flags |= p->u.zToken[0]=='"' ? EP_Quoted|EP_DblQuoted : EP_Quoted; 253 sqlite3Dequote(p->u.zToken); 254 } 255 256 /* 257 ** Generate a Token object from a string 258 */ 259 void sqlite3TokenInit(Token *p, char *z){ 260 p->z = z; 261 p->n = sqlite3Strlen30(z); 262 } 263 264 /* Convenient short-hand */ 265 #define UpperToLower sqlite3UpperToLower 266 267 /* 268 ** Some systems have stricmp(). Others have strcasecmp(). Because 269 ** there is no consistency, we will define our own. 270 ** 271 ** IMPLEMENTATION-OF: R-30243-02494 The sqlite3_stricmp() and 272 ** sqlite3_strnicmp() APIs allow applications and extensions to compare 273 ** the contents of two buffers containing UTF-8 strings in a 274 ** case-independent fashion, using the same definition of "case 275 ** independence" that SQLite uses internally when comparing identifiers. 276 */ 277 int sqlite3_stricmp(const char *zLeft, const char *zRight){ 278 if( zLeft==0 ){ 279 return zRight ? -1 : 0; 280 }else if( zRight==0 ){ 281 return 1; 282 } 283 return sqlite3StrICmp(zLeft, zRight); 284 } 285 int sqlite3StrICmp(const char *zLeft, const char *zRight){ 286 unsigned char *a, *b; 287 int c, x; 288 a = (unsigned char *)zLeft; 289 b = (unsigned char *)zRight; 290 for(;;){ 291 c = *a; 292 x = *b; 293 if( c==x ){ 294 if( c==0 ) break; 295 }else{ 296 c = (int)UpperToLower[c] - (int)UpperToLower[x]; 297 if( c ) break; 298 } 299 a++; 300 b++; 301 } 302 return c; 303 } 304 int sqlite3_strnicmp(const char *zLeft, const char *zRight, int N){ 305 register unsigned char *a, *b; 306 if( zLeft==0 ){ 307 return zRight ? -1 : 0; 308 }else if( zRight==0 ){ 309 return 1; 310 } 311 a = (unsigned char *)zLeft; 312 b = (unsigned char *)zRight; 313 while( N-- > 0 && *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; } 314 return N<0 ? 0 : UpperToLower[*a] - UpperToLower[*b]; 315 } 316 317 /* 318 ** Compute 10 to the E-th power. Examples: E==1 results in 10. 319 ** E==2 results in 100. E==50 results in 1.0e50. 320 ** 321 ** This routine only works for values of E between 1 and 341. 322 */ 323 static LONGDOUBLE_TYPE sqlite3Pow10(int E){ 324 #if defined(_MSC_VER) 325 static const LONGDOUBLE_TYPE x[] = { 326 1.0e+001L, 327 1.0e+002L, 328 1.0e+004L, 329 1.0e+008L, 330 1.0e+016L, 331 1.0e+032L, 332 1.0e+064L, 333 1.0e+128L, 334 1.0e+256L 335 }; 336 LONGDOUBLE_TYPE r = 1.0; 337 int i; 338 assert( E>=0 && E<=307 ); 339 for(i=0; E!=0; i++, E >>=1){ 340 if( E & 1 ) r *= x[i]; 341 } 342 return r; 343 #else 344 LONGDOUBLE_TYPE x = 10.0; 345 LONGDOUBLE_TYPE r = 1.0; 346 while(1){ 347 if( E & 1 ) r *= x; 348 E >>= 1; 349 if( E==0 ) break; 350 x *= x; 351 } 352 return r; 353 #endif 354 } 355 356 /* 357 ** The string z[] is an text representation of a real number. 358 ** Convert this string to a double and write it into *pResult. 359 ** 360 ** The string z[] is length bytes in length (bytes, not characters) and 361 ** uses the encoding enc. The string is not necessarily zero-terminated. 362 ** 363 ** Return TRUE if the result is a valid real number (or integer) and FALSE 364 ** if the string is empty or contains extraneous text. More specifically 365 ** return 366 ** 1 => The input string is a pure integer 367 ** 2 or more => The input has a decimal point or eNNN clause 368 ** 0 or less => The input string is not a valid number 369 ** -1 => Not a valid number, but has a valid prefix which 370 ** includes a decimal point and/or an eNNN clause 371 ** 372 ** Valid numbers are in one of these formats: 373 ** 374 ** [+-]digits[E[+-]digits] 375 ** [+-]digits.[digits][E[+-]digits] 376 ** [+-].digits[E[+-]digits] 377 ** 378 ** Leading and trailing whitespace is ignored for the purpose of determining 379 ** validity. 380 ** 381 ** If some prefix of the input string is a valid number, this routine 382 ** returns FALSE but it still converts the prefix and writes the result 383 ** into *pResult. 384 */ 385 #if defined(_MSC_VER) 386 #pragma warning(disable : 4756) 387 #endif 388 int sqlite3AtoF(const char *z, double *pResult, int length, u8 enc){ 389 #ifndef SQLITE_OMIT_FLOATING_POINT 390 int incr; 391 const char *zEnd = z + length; 392 /* sign * significand * (10 ^ (esign * exponent)) */ 393 int sign = 1; /* sign of significand */ 394 i64 s = 0; /* significand */ 395 int d = 0; /* adjust exponent for shifting decimal point */ 396 int esign = 1; /* sign of exponent */ 397 int e = 0; /* exponent */ 398 int eValid = 1; /* True exponent is either not used or is well-formed */ 399 double result; 400 int nDigit = 0; /* Number of digits processed */ 401 int eType = 1; /* 1: pure integer, 2+: fractional -1 or less: bad UTF16 */ 402 403 assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE ); 404 *pResult = 0.0; /* Default return value, in case of an error */ 405 406 if( enc==SQLITE_UTF8 ){ 407 incr = 1; 408 }else{ 409 int i; 410 incr = 2; 411 assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 ); 412 testcase( enc==SQLITE_UTF16LE ); 413 testcase( enc==SQLITE_UTF16BE ); 414 for(i=3-enc; i<length && z[i]==0; i+=2){} 415 if( i<length ) eType = -100; 416 zEnd = &z[i^1]; 417 z += (enc&1); 418 } 419 420 /* skip leading spaces */ 421 while( z<zEnd && sqlite3Isspace(*z) ) z+=incr; 422 if( z>=zEnd ) return 0; 423 424 /* get sign of significand */ 425 if( *z=='-' ){ 426 sign = -1; 427 z+=incr; 428 }else if( *z=='+' ){ 429 z+=incr; 430 } 431 432 /* copy max significant digits to significand */ 433 while( z<zEnd && sqlite3Isdigit(*z) ){ 434 s = s*10 + (*z - '0'); 435 z+=incr; nDigit++; 436 if( s>=((LARGEST_INT64-9)/10) ){ 437 /* skip non-significant significand digits 438 ** (increase exponent by d to shift decimal left) */ 439 while( z<zEnd && sqlite3Isdigit(*z) ){ z+=incr; d++; } 440 } 441 } 442 if( z>=zEnd ) goto do_atof_calc; 443 444 /* if decimal point is present */ 445 if( *z=='.' ){ 446 z+=incr; 447 eType++; 448 /* copy digits from after decimal to significand 449 ** (decrease exponent by d to shift decimal right) */ 450 while( z<zEnd && sqlite3Isdigit(*z) ){ 451 if( s<((LARGEST_INT64-9)/10) ){ 452 s = s*10 + (*z - '0'); 453 d--; 454 nDigit++; 455 } 456 z+=incr; 457 } 458 } 459 if( z>=zEnd ) goto do_atof_calc; 460 461 /* if exponent is present */ 462 if( *z=='e' || *z=='E' ){ 463 z+=incr; 464 eValid = 0; 465 eType++; 466 467 /* This branch is needed to avoid a (harmless) buffer overread. The 468 ** special comment alerts the mutation tester that the correct answer 469 ** is obtained even if the branch is omitted */ 470 if( z>=zEnd ) goto do_atof_calc; /*PREVENTS-HARMLESS-OVERREAD*/ 471 472 /* get sign of exponent */ 473 if( *z=='-' ){ 474 esign = -1; 475 z+=incr; 476 }else if( *z=='+' ){ 477 z+=incr; 478 } 479 /* copy digits to exponent */ 480 while( z<zEnd && sqlite3Isdigit(*z) ){ 481 e = e<10000 ? (e*10 + (*z - '0')) : 10000; 482 z+=incr; 483 eValid = 1; 484 } 485 } 486 487 /* skip trailing spaces */ 488 while( z<zEnd && sqlite3Isspace(*z) ) z+=incr; 489 490 do_atof_calc: 491 /* adjust exponent by d, and update sign */ 492 e = (e*esign) + d; 493 if( e<0 ) { 494 esign = -1; 495 e *= -1; 496 } else { 497 esign = 1; 498 } 499 500 if( s==0 ) { 501 /* In the IEEE 754 standard, zero is signed. */ 502 result = sign<0 ? -(double)0 : (double)0; 503 } else { 504 /* Attempt to reduce exponent. 505 ** 506 ** Branches that are not required for the correct answer but which only 507 ** help to obtain the correct answer faster are marked with special 508 ** comments, as a hint to the mutation tester. 509 */ 510 while( e>0 ){ /*OPTIMIZATION-IF-TRUE*/ 511 if( esign>0 ){ 512 if( s>=(LARGEST_INT64/10) ) break; /*OPTIMIZATION-IF-FALSE*/ 513 s *= 10; 514 }else{ 515 if( s%10!=0 ) break; /*OPTIMIZATION-IF-FALSE*/ 516 s /= 10; 517 } 518 e--; 519 } 520 521 /* adjust the sign of significand */ 522 s = sign<0 ? -s : s; 523 524 if( e==0 ){ /*OPTIMIZATION-IF-TRUE*/ 525 result = (double)s; 526 }else{ 527 /* attempt to handle extremely small/large numbers better */ 528 if( e>307 ){ /*OPTIMIZATION-IF-TRUE*/ 529 if( e<342 ){ /*OPTIMIZATION-IF-TRUE*/ 530 LONGDOUBLE_TYPE scale = sqlite3Pow10(e-308); 531 if( esign<0 ){ 532 result = s / scale; 533 result /= 1.0e+308; 534 }else{ 535 result = s * scale; 536 result *= 1.0e+308; 537 } 538 }else{ assert( e>=342 ); 539 if( esign<0 ){ 540 result = 0.0*s; 541 }else{ 542 #ifdef INFINITY 543 result = INFINITY*s; 544 #else 545 result = 1e308*1e308*s; /* Infinity */ 546 #endif 547 } 548 } 549 }else{ 550 LONGDOUBLE_TYPE scale = sqlite3Pow10(e); 551 if( esign<0 ){ 552 result = s / scale; 553 }else{ 554 result = s * scale; 555 } 556 } 557 } 558 } 559 560 /* store the result */ 561 *pResult = result; 562 563 /* return true if number and no extra non-whitespace chracters after */ 564 if( z==zEnd && nDigit>0 && eValid && eType>0 ){ 565 return eType; 566 }else if( eType>=2 && (eType==3 || eValid) && nDigit>0 ){ 567 return -1; 568 }else{ 569 return 0; 570 } 571 #else 572 return !sqlite3Atoi64(z, pResult, length, enc); 573 #endif /* SQLITE_OMIT_FLOATING_POINT */ 574 } 575 #if defined(_MSC_VER) 576 #pragma warning(default : 4756) 577 #endif 578 579 /* 580 ** Compare the 19-character string zNum against the text representation 581 ** value 2^63: 9223372036854775808. Return negative, zero, or positive 582 ** if zNum is less than, equal to, or greater than the string. 583 ** Note that zNum must contain exactly 19 characters. 584 ** 585 ** Unlike memcmp() this routine is guaranteed to return the difference 586 ** in the values of the last digit if the only difference is in the 587 ** last digit. So, for example, 588 ** 589 ** compare2pow63("9223372036854775800", 1) 590 ** 591 ** will return -8. 592 */ 593 static int compare2pow63(const char *zNum, int incr){ 594 int c = 0; 595 int i; 596 /* 012345678901234567 */ 597 const char *pow63 = "922337203685477580"; 598 for(i=0; c==0 && i<18; i++){ 599 c = (zNum[i*incr]-pow63[i])*10; 600 } 601 if( c==0 ){ 602 c = zNum[18*incr] - '8'; 603 testcase( c==(-1) ); 604 testcase( c==0 ); 605 testcase( c==(+1) ); 606 } 607 return c; 608 } 609 610 /* 611 ** Convert zNum to a 64-bit signed integer. zNum must be decimal. This 612 ** routine does *not* accept hexadecimal notation. 613 ** 614 ** Returns: 615 ** 616 ** -1 Not even a prefix of the input text looks like an integer 617 ** 0 Successful transformation. Fits in a 64-bit signed integer. 618 ** 1 Excess non-space text after the integer value 619 ** 2 Integer too large for a 64-bit signed integer or is malformed 620 ** 3 Special case of 9223372036854775808 621 ** 622 ** length is the number of bytes in the string (bytes, not characters). 623 ** The string is not necessarily zero-terminated. The encoding is 624 ** given by enc. 625 */ 626 int sqlite3Atoi64(const char *zNum, i64 *pNum, int length, u8 enc){ 627 int incr; 628 u64 u = 0; 629 int neg = 0; /* assume positive */ 630 int i; 631 int c = 0; 632 int nonNum = 0; /* True if input contains UTF16 with high byte non-zero */ 633 int rc; /* Baseline return code */ 634 const char *zStart; 635 const char *zEnd = zNum + length; 636 assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE ); 637 if( enc==SQLITE_UTF8 ){ 638 incr = 1; 639 }else{ 640 incr = 2; 641 assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 ); 642 for(i=3-enc; i<length && zNum[i]==0; i+=2){} 643 nonNum = i<length; 644 zEnd = &zNum[i^1]; 645 zNum += (enc&1); 646 } 647 while( zNum<zEnd && sqlite3Isspace(*zNum) ) zNum+=incr; 648 if( zNum<zEnd ){ 649 if( *zNum=='-' ){ 650 neg = 1; 651 zNum+=incr; 652 }else if( *zNum=='+' ){ 653 zNum+=incr; 654 } 655 } 656 zStart = zNum; 657 while( zNum<zEnd && zNum[0]=='0' ){ zNum+=incr; } /* Skip leading zeros. */ 658 for(i=0; &zNum[i]<zEnd && (c=zNum[i])>='0' && c<='9'; i+=incr){ 659 u = u*10 + c - '0'; 660 } 661 testcase( i==18*incr ); 662 testcase( i==19*incr ); 663 testcase( i==20*incr ); 664 if( u>LARGEST_INT64 ){ 665 /* This test and assignment is needed only to suppress UB warnings 666 ** from clang and -fsanitize=undefined. This test and assignment make 667 ** the code a little larger and slower, and no harm comes from omitting 668 ** them, but we must appaise the undefined-behavior pharisees. */ 669 *pNum = neg ? SMALLEST_INT64 : LARGEST_INT64; 670 }else if( neg ){ 671 *pNum = -(i64)u; 672 }else{ 673 *pNum = (i64)u; 674 } 675 rc = 0; 676 if( i==0 && zStart==zNum ){ /* No digits */ 677 rc = -1; 678 }else if( nonNum ){ /* UTF16 with high-order bytes non-zero */ 679 rc = 1; 680 }else if( &zNum[i]<zEnd ){ /* Extra bytes at the end */ 681 int jj = i; 682 do{ 683 if( !sqlite3Isspace(zNum[jj]) ){ 684 rc = 1; /* Extra non-space text after the integer */ 685 break; 686 } 687 jj += incr; 688 }while( &zNum[jj]<zEnd ); 689 } 690 if( i<19*incr ){ 691 /* Less than 19 digits, so we know that it fits in 64 bits */ 692 assert( u<=LARGEST_INT64 ); 693 return rc; 694 }else{ 695 /* zNum is a 19-digit numbers. Compare it against 9223372036854775808. */ 696 c = i>19*incr ? 1 : compare2pow63(zNum, incr); 697 if( c<0 ){ 698 /* zNum is less than 9223372036854775808 so it fits */ 699 assert( u<=LARGEST_INT64 ); 700 return rc; 701 }else{ 702 *pNum = neg ? SMALLEST_INT64 : LARGEST_INT64; 703 if( c>0 ){ 704 /* zNum is greater than 9223372036854775808 so it overflows */ 705 return 2; 706 }else{ 707 /* zNum is exactly 9223372036854775808. Fits if negative. The 708 ** special case 2 overflow if positive */ 709 assert( u-1==LARGEST_INT64 ); 710 return neg ? rc : 3; 711 } 712 } 713 } 714 } 715 716 /* 717 ** Transform a UTF-8 integer literal, in either decimal or hexadecimal, 718 ** into a 64-bit signed integer. This routine accepts hexadecimal literals, 719 ** whereas sqlite3Atoi64() does not. 720 ** 721 ** Returns: 722 ** 723 ** 0 Successful transformation. Fits in a 64-bit signed integer. 724 ** 1 Excess text after the integer value 725 ** 2 Integer too large for a 64-bit signed integer or is malformed 726 ** 3 Special case of 9223372036854775808 727 */ 728 int sqlite3DecOrHexToI64(const char *z, i64 *pOut){ 729 #ifndef SQLITE_OMIT_HEX_INTEGER 730 if( z[0]=='0' 731 && (z[1]=='x' || z[1]=='X') 732 ){ 733 u64 u = 0; 734 int i, k; 735 for(i=2; z[i]=='0'; i++){} 736 for(k=i; sqlite3Isxdigit(z[k]); k++){ 737 u = u*16 + sqlite3HexToInt(z[k]); 738 } 739 memcpy(pOut, &u, 8); 740 return (z[k]==0 && k-i<=16) ? 0 : 2; 741 }else 742 #endif /* SQLITE_OMIT_HEX_INTEGER */ 743 { 744 return sqlite3Atoi64(z, pOut, sqlite3Strlen30(z), SQLITE_UTF8); 745 } 746 } 747 748 /* 749 ** If zNum represents an integer that will fit in 32-bits, then set 750 ** *pValue to that integer and return true. Otherwise return false. 751 ** 752 ** This routine accepts both decimal and hexadecimal notation for integers. 753 ** 754 ** Any non-numeric characters that following zNum are ignored. 755 ** This is different from sqlite3Atoi64() which requires the 756 ** input number to be zero-terminated. 757 */ 758 int sqlite3GetInt32(const char *zNum, int *pValue){ 759 sqlite_int64 v = 0; 760 int i, c; 761 int neg = 0; 762 if( zNum[0]=='-' ){ 763 neg = 1; 764 zNum++; 765 }else if( zNum[0]=='+' ){ 766 zNum++; 767 } 768 #ifndef SQLITE_OMIT_HEX_INTEGER 769 else if( zNum[0]=='0' 770 && (zNum[1]=='x' || zNum[1]=='X') 771 && sqlite3Isxdigit(zNum[2]) 772 ){ 773 u32 u = 0; 774 zNum += 2; 775 while( zNum[0]=='0' ) zNum++; 776 for(i=0; sqlite3Isxdigit(zNum[i]) && i<8; i++){ 777 u = u*16 + sqlite3HexToInt(zNum[i]); 778 } 779 if( (u&0x80000000)==0 && sqlite3Isxdigit(zNum[i])==0 ){ 780 memcpy(pValue, &u, 4); 781 return 1; 782 }else{ 783 return 0; 784 } 785 } 786 #endif 787 if( !sqlite3Isdigit(zNum[0]) ) return 0; 788 while( zNum[0]=='0' ) zNum++; 789 for(i=0; i<11 && (c = zNum[i] - '0')>=0 && c<=9; i++){ 790 v = v*10 + c; 791 } 792 793 /* The longest decimal representation of a 32 bit integer is 10 digits: 794 ** 795 ** 1234567890 796 ** 2^31 -> 2147483648 797 */ 798 testcase( i==10 ); 799 if( i>10 ){ 800 return 0; 801 } 802 testcase( v-neg==2147483647 ); 803 if( v-neg>2147483647 ){ 804 return 0; 805 } 806 if( neg ){ 807 v = -v; 808 } 809 *pValue = (int)v; 810 return 1; 811 } 812 813 /* 814 ** Return a 32-bit integer value extracted from a string. If the 815 ** string is not an integer, just return 0. 816 */ 817 int sqlite3Atoi(const char *z){ 818 int x = 0; 819 if( z ) sqlite3GetInt32(z, &x); 820 return x; 821 } 822 823 /* 824 ** The variable-length integer encoding is as follows: 825 ** 826 ** KEY: 827 ** A = 0xxxxxxx 7 bits of data and one flag bit 828 ** B = 1xxxxxxx 7 bits of data and one flag bit 829 ** C = xxxxxxxx 8 bits of data 830 ** 831 ** 7 bits - A 832 ** 14 bits - BA 833 ** 21 bits - BBA 834 ** 28 bits - BBBA 835 ** 35 bits - BBBBA 836 ** 42 bits - BBBBBA 837 ** 49 bits - BBBBBBA 838 ** 56 bits - BBBBBBBA 839 ** 64 bits - BBBBBBBBC 840 */ 841 842 /* 843 ** Write a 64-bit variable-length integer to memory starting at p[0]. 844 ** The length of data write will be between 1 and 9 bytes. The number 845 ** of bytes written is returned. 846 ** 847 ** A variable-length integer consists of the lower 7 bits of each byte 848 ** for all bytes that have the 8th bit set and one byte with the 8th 849 ** bit clear. Except, if we get to the 9th byte, it stores the full 850 ** 8 bits and is the last byte. 851 */ 852 static int SQLITE_NOINLINE putVarint64(unsigned char *p, u64 v){ 853 int i, j, n; 854 u8 buf[10]; 855 if( v & (((u64)0xff000000)<<32) ){ 856 p[8] = (u8)v; 857 v >>= 8; 858 for(i=7; i>=0; i--){ 859 p[i] = (u8)((v & 0x7f) | 0x80); 860 v >>= 7; 861 } 862 return 9; 863 } 864 n = 0; 865 do{ 866 buf[n++] = (u8)((v & 0x7f) | 0x80); 867 v >>= 7; 868 }while( v!=0 ); 869 buf[0] &= 0x7f; 870 assert( n<=9 ); 871 for(i=0, j=n-1; j>=0; j--, i++){ 872 p[i] = buf[j]; 873 } 874 return n; 875 } 876 int sqlite3PutVarint(unsigned char *p, u64 v){ 877 if( v<=0x7f ){ 878 p[0] = v&0x7f; 879 return 1; 880 } 881 if( v<=0x3fff ){ 882 p[0] = ((v>>7)&0x7f)|0x80; 883 p[1] = v&0x7f; 884 return 2; 885 } 886 return putVarint64(p,v); 887 } 888 889 /* 890 ** Bitmasks used by sqlite3GetVarint(). These precomputed constants 891 ** are defined here rather than simply putting the constant expressions 892 ** inline in order to work around bugs in the RVT compiler. 893 ** 894 ** SLOT_2_0 A mask for (0x7f<<14) | 0x7f 895 ** 896 ** SLOT_4_2_0 A mask for (0x7f<<28) | SLOT_2_0 897 */ 898 #define SLOT_2_0 0x001fc07f 899 #define SLOT_4_2_0 0xf01fc07f 900 901 902 /* 903 ** Read a 64-bit variable-length integer from memory starting at p[0]. 904 ** Return the number of bytes read. The value is stored in *v. 905 */ 906 u8 sqlite3GetVarint(const unsigned char *p, u64 *v){ 907 u32 a,b,s; 908 909 if( ((signed char*)p)[0]>=0 ){ 910 *v = *p; 911 return 1; 912 } 913 if( ((signed char*)p)[1]>=0 ){ 914 *v = ((u32)(p[0]&0x7f)<<7) | p[1]; 915 return 2; 916 } 917 918 /* Verify that constants are precomputed correctly */ 919 assert( SLOT_2_0 == ((0x7f<<14) | (0x7f)) ); 920 assert( SLOT_4_2_0 == ((0xfU<<28) | (0x7f<<14) | (0x7f)) ); 921 922 a = ((u32)p[0])<<14; 923 b = p[1]; 924 p += 2; 925 a |= *p; 926 /* a: p0<<14 | p2 (unmasked) */ 927 if (!(a&0x80)) 928 { 929 a &= SLOT_2_0; 930 b &= 0x7f; 931 b = b<<7; 932 a |= b; 933 *v = a; 934 return 3; 935 } 936 937 /* CSE1 from below */ 938 a &= SLOT_2_0; 939 p++; 940 b = b<<14; 941 b |= *p; 942 /* b: p1<<14 | p3 (unmasked) */ 943 if (!(b&0x80)) 944 { 945 b &= SLOT_2_0; 946 /* moved CSE1 up */ 947 /* a &= (0x7f<<14)|(0x7f); */ 948 a = a<<7; 949 a |= b; 950 *v = a; 951 return 4; 952 } 953 954 /* a: p0<<14 | p2 (masked) */ 955 /* b: p1<<14 | p3 (unmasked) */ 956 /* 1:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */ 957 /* moved CSE1 up */ 958 /* a &= (0x7f<<14)|(0x7f); */ 959 b &= SLOT_2_0; 960 s = a; 961 /* s: p0<<14 | p2 (masked) */ 962 963 p++; 964 a = a<<14; 965 a |= *p; 966 /* a: p0<<28 | p2<<14 | p4 (unmasked) */ 967 if (!(a&0x80)) 968 { 969 /* we can skip these cause they were (effectively) done above 970 ** while calculating s */ 971 /* a &= (0x7f<<28)|(0x7f<<14)|(0x7f); */ 972 /* b &= (0x7f<<14)|(0x7f); */ 973 b = b<<7; 974 a |= b; 975 s = s>>18; 976 *v = ((u64)s)<<32 | a; 977 return 5; 978 } 979 980 /* 2:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */ 981 s = s<<7; 982 s |= b; 983 /* s: p0<<21 | p1<<14 | p2<<7 | p3 (masked) */ 984 985 p++; 986 b = b<<14; 987 b |= *p; 988 /* b: p1<<28 | p3<<14 | p5 (unmasked) */ 989 if (!(b&0x80)) 990 { 991 /* we can skip this cause it was (effectively) done above in calc'ing s */ 992 /* b &= (0x7f<<28)|(0x7f<<14)|(0x7f); */ 993 a &= SLOT_2_0; 994 a = a<<7; 995 a |= b; 996 s = s>>18; 997 *v = ((u64)s)<<32 | a; 998 return 6; 999 } 1000 1001 p++; 1002 a = a<<14; 1003 a |= *p; 1004 /* a: p2<<28 | p4<<14 | p6 (unmasked) */ 1005 if (!(a&0x80)) 1006 { 1007 a &= SLOT_4_2_0; 1008 b &= SLOT_2_0; 1009 b = b<<7; 1010 a |= b; 1011 s = s>>11; 1012 *v = ((u64)s)<<32 | a; 1013 return 7; 1014 } 1015 1016 /* CSE2 from below */ 1017 a &= SLOT_2_0; 1018 p++; 1019 b = b<<14; 1020 b |= *p; 1021 /* b: p3<<28 | p5<<14 | p7 (unmasked) */ 1022 if (!(b&0x80)) 1023 { 1024 b &= SLOT_4_2_0; 1025 /* moved CSE2 up */ 1026 /* a &= (0x7f<<14)|(0x7f); */ 1027 a = a<<7; 1028 a |= b; 1029 s = s>>4; 1030 *v = ((u64)s)<<32 | a; 1031 return 8; 1032 } 1033 1034 p++; 1035 a = a<<15; 1036 a |= *p; 1037 /* a: p4<<29 | p6<<15 | p8 (unmasked) */ 1038 1039 /* moved CSE2 up */ 1040 /* a &= (0x7f<<29)|(0x7f<<15)|(0xff); */ 1041 b &= SLOT_2_0; 1042 b = b<<8; 1043 a |= b; 1044 1045 s = s<<4; 1046 b = p[-4]; 1047 b &= 0x7f; 1048 b = b>>3; 1049 s |= b; 1050 1051 *v = ((u64)s)<<32 | a; 1052 1053 return 9; 1054 } 1055 1056 /* 1057 ** Read a 32-bit variable-length integer from memory starting at p[0]. 1058 ** Return the number of bytes read. The value is stored in *v. 1059 ** 1060 ** If the varint stored in p[0] is larger than can fit in a 32-bit unsigned 1061 ** integer, then set *v to 0xffffffff. 1062 ** 1063 ** A MACRO version, getVarint32, is provided which inlines the 1064 ** single-byte case. All code should use the MACRO version as 1065 ** this function assumes the single-byte case has already been handled. 1066 */ 1067 u8 sqlite3GetVarint32(const unsigned char *p, u32 *v){ 1068 u32 a,b; 1069 1070 /* The 1-byte case. Overwhelmingly the most common. Handled inline 1071 ** by the getVarin32() macro */ 1072 a = *p; 1073 /* a: p0 (unmasked) */ 1074 #ifndef getVarint32 1075 if (!(a&0x80)) 1076 { 1077 /* Values between 0 and 127 */ 1078 *v = a; 1079 return 1; 1080 } 1081 #endif 1082 1083 /* The 2-byte case */ 1084 p++; 1085 b = *p; 1086 /* b: p1 (unmasked) */ 1087 if (!(b&0x80)) 1088 { 1089 /* Values between 128 and 16383 */ 1090 a &= 0x7f; 1091 a = a<<7; 1092 *v = a | b; 1093 return 2; 1094 } 1095 1096 /* The 3-byte case */ 1097 p++; 1098 a = a<<14; 1099 a |= *p; 1100 /* a: p0<<14 | p2 (unmasked) */ 1101 if (!(a&0x80)) 1102 { 1103 /* Values between 16384 and 2097151 */ 1104 a &= (0x7f<<14)|(0x7f); 1105 b &= 0x7f; 1106 b = b<<7; 1107 *v = a | b; 1108 return 3; 1109 } 1110 1111 /* A 32-bit varint is used to store size information in btrees. 1112 ** Objects are rarely larger than 2MiB limit of a 3-byte varint. 1113 ** A 3-byte varint is sufficient, for example, to record the size 1114 ** of a 1048569-byte BLOB or string. 1115 ** 1116 ** We only unroll the first 1-, 2-, and 3- byte cases. The very 1117 ** rare larger cases can be handled by the slower 64-bit varint 1118 ** routine. 1119 */ 1120 #if 1 1121 { 1122 u64 v64; 1123 u8 n; 1124 1125 p -= 2; 1126 n = sqlite3GetVarint(p, &v64); 1127 assert( n>3 && n<=9 ); 1128 if( (v64 & SQLITE_MAX_U32)!=v64 ){ 1129 *v = 0xffffffff; 1130 }else{ 1131 *v = (u32)v64; 1132 } 1133 return n; 1134 } 1135 1136 #else 1137 /* For following code (kept for historical record only) shows an 1138 ** unrolling for the 3- and 4-byte varint cases. This code is 1139 ** slightly faster, but it is also larger and much harder to test. 1140 */ 1141 p++; 1142 b = b<<14; 1143 b |= *p; 1144 /* b: p1<<14 | p3 (unmasked) */ 1145 if (!(b&0x80)) 1146 { 1147 /* Values between 2097152 and 268435455 */ 1148 b &= (0x7f<<14)|(0x7f); 1149 a &= (0x7f<<14)|(0x7f); 1150 a = a<<7; 1151 *v = a | b; 1152 return 4; 1153 } 1154 1155 p++; 1156 a = a<<14; 1157 a |= *p; 1158 /* a: p0<<28 | p2<<14 | p4 (unmasked) */ 1159 if (!(a&0x80)) 1160 { 1161 /* Values between 268435456 and 34359738367 */ 1162 a &= SLOT_4_2_0; 1163 b &= SLOT_4_2_0; 1164 b = b<<7; 1165 *v = a | b; 1166 return 5; 1167 } 1168 1169 /* We can only reach this point when reading a corrupt database 1170 ** file. In that case we are not in any hurry. Use the (relatively 1171 ** slow) general-purpose sqlite3GetVarint() routine to extract the 1172 ** value. */ 1173 { 1174 u64 v64; 1175 u8 n; 1176 1177 p -= 4; 1178 n = sqlite3GetVarint(p, &v64); 1179 assert( n>5 && n<=9 ); 1180 *v = (u32)v64; 1181 return n; 1182 } 1183 #endif 1184 } 1185 1186 /* 1187 ** Return the number of bytes that will be needed to store the given 1188 ** 64-bit integer. 1189 */ 1190 int sqlite3VarintLen(u64 v){ 1191 int i; 1192 for(i=1; (v >>= 7)!=0; i++){ assert( i<10 ); } 1193 return i; 1194 } 1195 1196 1197 /* 1198 ** Read or write a four-byte big-endian integer value. 1199 */ 1200 u32 sqlite3Get4byte(const u8 *p){ 1201 #if SQLITE_BYTEORDER==4321 1202 u32 x; 1203 memcpy(&x,p,4); 1204 return x; 1205 #elif SQLITE_BYTEORDER==1234 && GCC_VERSION>=4003000 1206 u32 x; 1207 memcpy(&x,p,4); 1208 return __builtin_bswap32(x); 1209 #elif SQLITE_BYTEORDER==1234 && MSVC_VERSION>=1300 1210 u32 x; 1211 memcpy(&x,p,4); 1212 return _byteswap_ulong(x); 1213 #else 1214 testcase( p[0]&0x80 ); 1215 return ((unsigned)p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3]; 1216 #endif 1217 } 1218 void sqlite3Put4byte(unsigned char *p, u32 v){ 1219 #if SQLITE_BYTEORDER==4321 1220 memcpy(p,&v,4); 1221 #elif SQLITE_BYTEORDER==1234 && GCC_VERSION>=4003000 1222 u32 x = __builtin_bswap32(v); 1223 memcpy(p,&x,4); 1224 #elif SQLITE_BYTEORDER==1234 && MSVC_VERSION>=1300 1225 u32 x = _byteswap_ulong(v); 1226 memcpy(p,&x,4); 1227 #else 1228 p[0] = (u8)(v>>24); 1229 p[1] = (u8)(v>>16); 1230 p[2] = (u8)(v>>8); 1231 p[3] = (u8)v; 1232 #endif 1233 } 1234 1235 1236 1237 /* 1238 ** Translate a single byte of Hex into an integer. 1239 ** This routine only works if h really is a valid hexadecimal 1240 ** character: 0..9a..fA..F 1241 */ 1242 u8 sqlite3HexToInt(int h){ 1243 assert( (h>='0' && h<='9') || (h>='a' && h<='f') || (h>='A' && h<='F') ); 1244 #ifdef SQLITE_ASCII 1245 h += 9*(1&(h>>6)); 1246 #endif 1247 #ifdef SQLITE_EBCDIC 1248 h += 9*(1&~(h>>4)); 1249 #endif 1250 return (u8)(h & 0xf); 1251 } 1252 1253 #if !defined(SQLITE_OMIT_BLOB_LITERAL) || defined(SQLITE_HAS_CODEC) 1254 /* 1255 ** Convert a BLOB literal of the form "x'hhhhhh'" into its binary 1256 ** value. Return a pointer to its binary value. Space to hold the 1257 ** binary value has been obtained from malloc and must be freed by 1258 ** the calling routine. 1259 */ 1260 void *sqlite3HexToBlob(sqlite3 *db, const char *z, int n){ 1261 char *zBlob; 1262 int i; 1263 1264 zBlob = (char *)sqlite3DbMallocRawNN(db, n/2 + 1); 1265 n--; 1266 if( zBlob ){ 1267 for(i=0; i<n; i+=2){ 1268 zBlob[i/2] = (sqlite3HexToInt(z[i])<<4) | sqlite3HexToInt(z[i+1]); 1269 } 1270 zBlob[i/2] = 0; 1271 } 1272 return zBlob; 1273 } 1274 #endif /* !SQLITE_OMIT_BLOB_LITERAL || SQLITE_HAS_CODEC */ 1275 1276 /* 1277 ** Log an error that is an API call on a connection pointer that should 1278 ** not have been used. The "type" of connection pointer is given as the 1279 ** argument. The zType is a word like "NULL" or "closed" or "invalid". 1280 */ 1281 static void logBadConnection(const char *zType){ 1282 sqlite3_log(SQLITE_MISUSE, 1283 "API call with %s database connection pointer", 1284 zType 1285 ); 1286 } 1287 1288 /* 1289 ** Check to make sure we have a valid db pointer. This test is not 1290 ** foolproof but it does provide some measure of protection against 1291 ** misuse of the interface such as passing in db pointers that are 1292 ** NULL or which have been previously closed. If this routine returns 1293 ** 1 it means that the db pointer is valid and 0 if it should not be 1294 ** dereferenced for any reason. The calling function should invoke 1295 ** SQLITE_MISUSE immediately. 1296 ** 1297 ** sqlite3SafetyCheckOk() requires that the db pointer be valid for 1298 ** use. sqlite3SafetyCheckSickOrOk() allows a db pointer that failed to 1299 ** open properly and is not fit for general use but which can be 1300 ** used as an argument to sqlite3_errmsg() or sqlite3_close(). 1301 */ 1302 int sqlite3SafetyCheckOk(sqlite3 *db){ 1303 u32 magic; 1304 if( db==0 ){ 1305 logBadConnection("NULL"); 1306 return 0; 1307 } 1308 magic = db->magic; 1309 if( magic!=SQLITE_MAGIC_OPEN ){ 1310 if( sqlite3SafetyCheckSickOrOk(db) ){ 1311 testcase( sqlite3GlobalConfig.xLog!=0 ); 1312 logBadConnection("unopened"); 1313 } 1314 return 0; 1315 }else{ 1316 return 1; 1317 } 1318 } 1319 int sqlite3SafetyCheckSickOrOk(sqlite3 *db){ 1320 u32 magic; 1321 magic = db->magic; 1322 if( magic!=SQLITE_MAGIC_SICK && 1323 magic!=SQLITE_MAGIC_OPEN && 1324 magic!=SQLITE_MAGIC_BUSY ){ 1325 testcase( sqlite3GlobalConfig.xLog!=0 ); 1326 logBadConnection("invalid"); 1327 return 0; 1328 }else{ 1329 return 1; 1330 } 1331 } 1332 1333 /* 1334 ** Attempt to add, substract, or multiply the 64-bit signed value iB against 1335 ** the other 64-bit signed integer at *pA and store the result in *pA. 1336 ** Return 0 on success. Or if the operation would have resulted in an 1337 ** overflow, leave *pA unchanged and return 1. 1338 */ 1339 int sqlite3AddInt64(i64 *pA, i64 iB){ 1340 #if GCC_VERSION>=5004000 && !defined(__INTEL_COMPILER) 1341 return __builtin_add_overflow(*pA, iB, pA); 1342 #else 1343 i64 iA = *pA; 1344 testcase( iA==0 ); testcase( iA==1 ); 1345 testcase( iB==-1 ); testcase( iB==0 ); 1346 if( iB>=0 ){ 1347 testcase( iA>0 && LARGEST_INT64 - iA == iB ); 1348 testcase( iA>0 && LARGEST_INT64 - iA == iB - 1 ); 1349 if( iA>0 && LARGEST_INT64 - iA < iB ) return 1; 1350 }else{ 1351 testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 1 ); 1352 testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 2 ); 1353 if( iA<0 && -(iA + LARGEST_INT64) > iB + 1 ) return 1; 1354 } 1355 *pA += iB; 1356 return 0; 1357 #endif 1358 } 1359 int sqlite3SubInt64(i64 *pA, i64 iB){ 1360 #if GCC_VERSION>=5004000 && !defined(__INTEL_COMPILER) 1361 return __builtin_sub_overflow(*pA, iB, pA); 1362 #else 1363 testcase( iB==SMALLEST_INT64+1 ); 1364 if( iB==SMALLEST_INT64 ){ 1365 testcase( (*pA)==(-1) ); testcase( (*pA)==0 ); 1366 if( (*pA)>=0 ) return 1; 1367 *pA -= iB; 1368 return 0; 1369 }else{ 1370 return sqlite3AddInt64(pA, -iB); 1371 } 1372 #endif 1373 } 1374 int sqlite3MulInt64(i64 *pA, i64 iB){ 1375 #if GCC_VERSION>=5004000 && !defined(__INTEL_COMPILER) 1376 return __builtin_mul_overflow(*pA, iB, pA); 1377 #else 1378 i64 iA = *pA; 1379 if( iB>0 ){ 1380 if( iA>LARGEST_INT64/iB ) return 1; 1381 if( iA<SMALLEST_INT64/iB ) return 1; 1382 }else if( iB<0 ){ 1383 if( iA>0 ){ 1384 if( iB<SMALLEST_INT64/iA ) return 1; 1385 }else if( iA<0 ){ 1386 if( iB==SMALLEST_INT64 ) return 1; 1387 if( iA==SMALLEST_INT64 ) return 1; 1388 if( -iA>LARGEST_INT64/-iB ) return 1; 1389 } 1390 } 1391 *pA = iA*iB; 1392 return 0; 1393 #endif 1394 } 1395 1396 /* 1397 ** Compute the absolute value of a 32-bit signed integer, of possible. Or 1398 ** if the integer has a value of -2147483648, return +2147483647 1399 */ 1400 int sqlite3AbsInt32(int x){ 1401 if( x>=0 ) return x; 1402 if( x==(int)0x80000000 ) return 0x7fffffff; 1403 return -x; 1404 } 1405 1406 #ifdef SQLITE_ENABLE_8_3_NAMES 1407 /* 1408 ** If SQLITE_ENABLE_8_3_NAMES is set at compile-time and if the database 1409 ** filename in zBaseFilename is a URI with the "8_3_names=1" parameter and 1410 ** if filename in z[] has a suffix (a.k.a. "extension") that is longer than 1411 ** three characters, then shorten the suffix on z[] to be the last three 1412 ** characters of the original suffix. 1413 ** 1414 ** If SQLITE_ENABLE_8_3_NAMES is set to 2 at compile-time, then always 1415 ** do the suffix shortening regardless of URI parameter. 1416 ** 1417 ** Examples: 1418 ** 1419 ** test.db-journal => test.nal 1420 ** test.db-wal => test.wal 1421 ** test.db-shm => test.shm 1422 ** test.db-mj7f3319fa => test.9fa 1423 */ 1424 void sqlite3FileSuffix3(const char *zBaseFilename, char *z){ 1425 #if SQLITE_ENABLE_8_3_NAMES<2 1426 if( sqlite3_uri_boolean(zBaseFilename, "8_3_names", 0) ) 1427 #endif 1428 { 1429 int i, sz; 1430 sz = sqlite3Strlen30(z); 1431 for(i=sz-1; i>0 && z[i]!='/' && z[i]!='.'; i--){} 1432 if( z[i]=='.' && ALWAYS(sz>i+4) ) memmove(&z[i+1], &z[sz-3], 4); 1433 } 1434 } 1435 #endif 1436 1437 /* 1438 ** Find (an approximate) sum of two LogEst values. This computation is 1439 ** not a simple "+" operator because LogEst is stored as a logarithmic 1440 ** value. 1441 ** 1442 */ 1443 LogEst sqlite3LogEstAdd(LogEst a, LogEst b){ 1444 static const unsigned char x[] = { 1445 10, 10, /* 0,1 */ 1446 9, 9, /* 2,3 */ 1447 8, 8, /* 4,5 */ 1448 7, 7, 7, /* 6,7,8 */ 1449 6, 6, 6, /* 9,10,11 */ 1450 5, 5, 5, /* 12-14 */ 1451 4, 4, 4, 4, /* 15-18 */ 1452 3, 3, 3, 3, 3, 3, /* 19-24 */ 1453 2, 2, 2, 2, 2, 2, 2, /* 25-31 */ 1454 }; 1455 if( a>=b ){ 1456 if( a>b+49 ) return a; 1457 if( a>b+31 ) return a+1; 1458 return a+x[a-b]; 1459 }else{ 1460 if( b>a+49 ) return b; 1461 if( b>a+31 ) return b+1; 1462 return b+x[b-a]; 1463 } 1464 } 1465 1466 /* 1467 ** Convert an integer into a LogEst. In other words, compute an 1468 ** approximation for 10*log2(x). 1469 */ 1470 LogEst sqlite3LogEst(u64 x){ 1471 static LogEst a[] = { 0, 2, 3, 5, 6, 7, 8, 9 }; 1472 LogEst y = 40; 1473 if( x<8 ){ 1474 if( x<2 ) return 0; 1475 while( x<8 ){ y -= 10; x <<= 1; } 1476 }else{ 1477 #if GCC_VERSION>=5004000 1478 int i = 60 - __builtin_clzll(x); 1479 y += i*10; 1480 x >>= i; 1481 #else 1482 while( x>255 ){ y += 40; x >>= 4; } /*OPTIMIZATION-IF-TRUE*/ 1483 while( x>15 ){ y += 10; x >>= 1; } 1484 #endif 1485 } 1486 return a[x&7] + y - 10; 1487 } 1488 1489 #ifndef SQLITE_OMIT_VIRTUALTABLE 1490 /* 1491 ** Convert a double into a LogEst 1492 ** In other words, compute an approximation for 10*log2(x). 1493 */ 1494 LogEst sqlite3LogEstFromDouble(double x){ 1495 u64 a; 1496 LogEst e; 1497 assert( sizeof(x)==8 && sizeof(a)==8 ); 1498 if( x<=1 ) return 0; 1499 if( x<=2000000000 ) return sqlite3LogEst((u64)x); 1500 memcpy(&a, &x, 8); 1501 e = (a>>52) - 1022; 1502 return e*10; 1503 } 1504 #endif /* SQLITE_OMIT_VIRTUALTABLE */ 1505 1506 #if defined(SQLITE_ENABLE_STMT_SCANSTATUS) || \ 1507 defined(SQLITE_ENABLE_STAT4) || \ 1508 defined(SQLITE_EXPLAIN_ESTIMATED_ROWS) 1509 /* 1510 ** Convert a LogEst into an integer. 1511 ** 1512 ** Note that this routine is only used when one or more of various 1513 ** non-standard compile-time options is enabled. 1514 */ 1515 u64 sqlite3LogEstToInt(LogEst x){ 1516 u64 n; 1517 n = x%10; 1518 x /= 10; 1519 if( n>=5 ) n -= 2; 1520 else if( n>=1 ) n -= 1; 1521 #if defined(SQLITE_ENABLE_STMT_SCANSTATUS) || \ 1522 defined(SQLITE_EXPLAIN_ESTIMATED_ROWS) 1523 if( x>60 ) return (u64)LARGEST_INT64; 1524 #else 1525 /* If only SQLITE_ENABLE_STAT4 is on, then the largest input 1526 ** possible to this routine is 310, resulting in a maximum x of 31 */ 1527 assert( x<=60 ); 1528 #endif 1529 return x>=3 ? (n+8)<<(x-3) : (n+8)>>(3-x); 1530 } 1531 #endif /* defined SCANSTAT or STAT4 or ESTIMATED_ROWS */ 1532 1533 /* 1534 ** Add a new name/number pair to a VList. This might require that the 1535 ** VList object be reallocated, so return the new VList. If an OOM 1536 ** error occurs, the original VList returned and the 1537 ** db->mallocFailed flag is set. 1538 ** 1539 ** A VList is really just an array of integers. To destroy a VList, 1540 ** simply pass it to sqlite3DbFree(). 1541 ** 1542 ** The first integer is the number of integers allocated for the whole 1543 ** VList. The second integer is the number of integers actually used. 1544 ** Each name/number pair is encoded by subsequent groups of 3 or more 1545 ** integers. 1546 ** 1547 ** Each name/number pair starts with two integers which are the numeric 1548 ** value for the pair and the size of the name/number pair, respectively. 1549 ** The text name overlays one or more following integers. The text name 1550 ** is always zero-terminated. 1551 ** 1552 ** Conceptually: 1553 ** 1554 ** struct VList { 1555 ** int nAlloc; // Number of allocated slots 1556 ** int nUsed; // Number of used slots 1557 ** struct VListEntry { 1558 ** int iValue; // Value for this entry 1559 ** int nSlot; // Slots used by this entry 1560 ** // ... variable name goes here 1561 ** } a[0]; 1562 ** } 1563 ** 1564 ** During code generation, pointers to the variable names within the 1565 ** VList are taken. When that happens, nAlloc is set to zero as an 1566 ** indication that the VList may never again be enlarged, since the 1567 ** accompanying realloc() would invalidate the pointers. 1568 */ 1569 VList *sqlite3VListAdd( 1570 sqlite3 *db, /* The database connection used for malloc() */ 1571 VList *pIn, /* The input VList. Might be NULL */ 1572 const char *zName, /* Name of symbol to add */ 1573 int nName, /* Bytes of text in zName */ 1574 int iVal /* Value to associate with zName */ 1575 ){ 1576 int nInt; /* number of sizeof(int) objects needed for zName */ 1577 char *z; /* Pointer to where zName will be stored */ 1578 int i; /* Index in pIn[] where zName is stored */ 1579 1580 nInt = nName/4 + 3; 1581 assert( pIn==0 || pIn[0]>=3 ); /* Verify ok to add new elements */ 1582 if( pIn==0 || pIn[1]+nInt > pIn[0] ){ 1583 /* Enlarge the allocation */ 1584 sqlite3_int64 nAlloc = (pIn ? 2*(sqlite3_int64)pIn[0] : 10) + nInt; 1585 VList *pOut = sqlite3DbRealloc(db, pIn, nAlloc*sizeof(int)); 1586 if( pOut==0 ) return pIn; 1587 if( pIn==0 ) pOut[1] = 2; 1588 pIn = pOut; 1589 pIn[0] = nAlloc; 1590 } 1591 i = pIn[1]; 1592 pIn[i] = iVal; 1593 pIn[i+1] = nInt; 1594 z = (char*)&pIn[i+2]; 1595 pIn[1] = i+nInt; 1596 assert( pIn[1]<=pIn[0] ); 1597 memcpy(z, zName, nName); 1598 z[nName] = 0; 1599 return pIn; 1600 } 1601 1602 /* 1603 ** Return a pointer to the name of a variable in the given VList that 1604 ** has the value iVal. Or return a NULL if there is no such variable in 1605 ** the list 1606 */ 1607 const char *sqlite3VListNumToName(VList *pIn, int iVal){ 1608 int i, mx; 1609 if( pIn==0 ) return 0; 1610 mx = pIn[1]; 1611 i = 2; 1612 do{ 1613 if( pIn[i]==iVal ) return (char*)&pIn[i+2]; 1614 i += pIn[i+1]; 1615 }while( i<mx ); 1616 return 0; 1617 } 1618 1619 /* 1620 ** Return the number of the variable named zName, if it is in VList. 1621 ** or return 0 if there is no such variable. 1622 */ 1623 int sqlite3VListNameToNum(VList *pIn, const char *zName, int nName){ 1624 int i, mx; 1625 if( pIn==0 ) return 0; 1626 mx = pIn[1]; 1627 i = 2; 1628 do{ 1629 const char *z = (const char*)&pIn[i+2]; 1630 if( strncmp(z,zName,nName)==0 && z[nName]==0 ) return pIn[i]; 1631 i += pIn[i+1]; 1632 }while( i<mx ); 1633 return 0; 1634 } 1635