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+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** Utility functions used throughout sqlite.
+**
+** This file contains functions for allocating memory, comparing
+** strings, and stuff like that.
+**
+*/
+#include "sqliteInt.h"
+#include <stdarg.h>
+#ifndef SQLITE_OMIT_FLOATING_POINT
+#include <math.h>
+#endif
+
+/*
+** Calls to sqlite3FaultSim() are used to simulate a failure during testing,
+** or to bypass normal error detection during testing in order to let
+** execute proceed futher downstream.
+**
+** In deployment, sqlite3FaultSim() *always* return SQLITE_OK (0). The
+** sqlite3FaultSim() function only returns non-zero during testing.
+**
+** During testing, if the test harness has set a fault-sim callback using
+** a call to sqlite3_test_control(SQLITE_TESTCTRL_FAULT_INSTALL), then
+** each call to sqlite3FaultSim() is relayed to that application-supplied
+** callback and the integer return value form the application-supplied
+** callback is returned by sqlite3FaultSim().
+**
+** The integer argument to sqlite3FaultSim() is a code to identify which
+** sqlite3FaultSim() instance is being invoked. Each call to sqlite3FaultSim()
+** should have a unique code. To prevent legacy testing applications from
+** breaking, the codes should not be changed or reused.
+*/
+#ifndef SQLITE_UNTESTABLE
+int sqlite3FaultSim(int iTest){
+ int (*xCallback)(int) = sqlite3GlobalConfig.xTestCallback;
+ return xCallback ? xCallback(iTest) : SQLITE_OK;
+}
+#endif
+
+#ifndef SQLITE_OMIT_FLOATING_POINT
+/*
+** Return true if the floating point value is Not a Number (NaN).
+**
+** Use the math library isnan() function if compiled with SQLITE_HAVE_ISNAN.
+** Otherwise, we have our own implementation that works on most systems.
+*/
+int sqlite3IsNaN(double x){
+ int rc; /* The value return */
+#if !SQLITE_HAVE_ISNAN && !HAVE_ISNAN
+ u64 y;
+ memcpy(&y,&x,sizeof(y));
+ rc = IsNaN(y);
+#else
+ rc = isnan(x);
+#endif /* HAVE_ISNAN */
+ testcase( rc );
+ return rc;
+}
+#endif /* SQLITE_OMIT_FLOATING_POINT */
+
+/*
+** Compute a string length that is limited to what can be stored in
+** lower 30 bits of a 32-bit signed integer.
+**
+** The value returned will never be negative. Nor will it ever be greater
+** than the actual length of the string. For very long strings (greater
+** than 1GiB) the value returned might be less than the true string length.
+*/
+int sqlite3Strlen30(const char *z){
+ if( z==0 ) return 0;
+ return 0x3fffffff & (int)strlen(z);
+}
+
+/*
+** Return the declared type of a column. Or return zDflt if the column
+** has no declared type.
+**
+** The column type is an extra string stored after the zero-terminator on
+** the column name if and only if the COLFLAG_HASTYPE flag is set.
+*/
+char *sqlite3ColumnType(Column *pCol, char *zDflt){
+ if( pCol->colFlags & COLFLAG_HASTYPE ){
+ return pCol->zCnName + strlen(pCol->zCnName) + 1;
+ }else if( pCol->eCType ){
+ assert( pCol->eCType<=SQLITE_N_STDTYPE );
+ return (char*)sqlite3StdType[pCol->eCType-1];
+ }else{
+ return zDflt;
+ }
+}
+
+/*
+** Helper function for sqlite3Error() - called rarely. Broken out into
+** a separate routine to avoid unnecessary register saves on entry to
+** sqlite3Error().
+*/
+static SQLITE_NOINLINE void sqlite3ErrorFinish(sqlite3 *db, int err_code){
+ if( db->pErr ) sqlite3ValueSetNull(db->pErr);
+ sqlite3SystemError(db, err_code);
+}
+
+/*
+** Set the current error code to err_code and clear any prior error message.
+** Also set iSysErrno (by calling sqlite3System) if the err_code indicates
+** that would be appropriate.
+*/
+void sqlite3Error(sqlite3 *db, int err_code){
+ assert( db!=0 );
+ db->errCode = err_code;
+ if( err_code || db->pErr ){
+ sqlite3ErrorFinish(db, err_code);
+ }else{
+ db->errByteOffset = -1;
+ }
+}
+
+/*
+** The equivalent of sqlite3Error(db, SQLITE_OK). Clear the error state
+** and error message.
+*/
+void sqlite3ErrorClear(sqlite3 *db){
+ assert( db!=0 );
+ db->errCode = SQLITE_OK;
+ db->errByteOffset = -1;
+ if( db->pErr ) sqlite3ValueSetNull(db->pErr);
+}
+
+/*
+** Load the sqlite3.iSysErrno field if that is an appropriate thing
+** to do based on the SQLite error code in rc.
+*/
+void sqlite3SystemError(sqlite3 *db, int rc){
+ if( rc==SQLITE_IOERR_NOMEM ) return;
+ rc &= 0xff;
+ if( rc==SQLITE_CANTOPEN || rc==SQLITE_IOERR ){
+ db->iSysErrno = sqlite3OsGetLastError(db->pVfs);
+ }
+}
+
+/*
+** Set the most recent error code and error string for the sqlite
+** handle "db". The error code is set to "err_code".
+**
+** If it is not NULL, string zFormat specifies the format of the
+** error string. zFormat and any string tokens that follow it are
+** assumed to be encoded in UTF-8.
+**
+** To clear the most recent error for sqlite handle "db", sqlite3Error
+** should be called with err_code set to SQLITE_OK and zFormat set
+** to NULL.
+*/
+void sqlite3ErrorWithMsg(sqlite3 *db, int err_code, const char *zFormat, ...){
+ assert( db!=0 );
+ db->errCode = err_code;
+ sqlite3SystemError(db, err_code);
+ if( zFormat==0 ){
+ sqlite3Error(db, err_code);
+ }else if( db->pErr || (db->pErr = sqlite3ValueNew(db))!=0 ){
+ char *z;
+ va_list ap;
+ va_start(ap, zFormat);
+ z = sqlite3VMPrintf(db, zFormat, ap);
+ va_end(ap);
+ sqlite3ValueSetStr(db->pErr, -1, z, SQLITE_UTF8, SQLITE_DYNAMIC);
+ }
+}
+
+/*
+** Add an error message to pParse->zErrMsg and increment pParse->nErr.
+**
+** This function should be used to report any error that occurs while
+** compiling an SQL statement (i.e. within sqlite3_prepare()). The
+** last thing the sqlite3_prepare() function does is copy the error
+** stored by this function into the database handle using sqlite3Error().
+** Functions sqlite3Error() or sqlite3ErrorWithMsg() should be used
+** during statement execution (sqlite3_step() etc.).
+*/
+void sqlite3ErrorMsg(Parse *pParse, const char *zFormat, ...){
+ char *zMsg;
+ va_list ap;
+ sqlite3 *db = pParse->db;
+ assert( db!=0 );
+ assert( db->pParse==pParse || db->pParse->pToplevel==pParse );
+ db->errByteOffset = -2;
+ va_start(ap, zFormat);
+ zMsg = sqlite3VMPrintf(db, zFormat, ap);
+ va_end(ap);
+ if( db->errByteOffset<-1 ) db->errByteOffset = -1;
+ if( db->suppressErr ){
+ sqlite3DbFree(db, zMsg);
+ if( db->mallocFailed ){
+ pParse->nErr++;
+ pParse->rc = SQLITE_NOMEM;
+ }
+ }else{
+ pParse->nErr++;
+ sqlite3DbFree(db, pParse->zErrMsg);
+ pParse->zErrMsg = zMsg;
+ pParse->rc = SQLITE_ERROR;
+ pParse->pWith = 0;
+ }
+}
+
+/*
+** If database connection db is currently parsing SQL, then transfer
+** error code errCode to that parser if the parser has not already
+** encountered some other kind of error.
+*/
+int sqlite3ErrorToParser(sqlite3 *db, int errCode){
+ Parse *pParse;
+ if( db==0 || (pParse = db->pParse)==0 ) return errCode;
+ pParse->rc = errCode;
+ pParse->nErr++;
+ return errCode;
+}
+
+/*
+** Convert an SQL-style quoted string into a normal string by removing
+** the quote characters. The conversion is done in-place. If the
+** input does not begin with a quote character, then this routine
+** is a no-op.
+**
+** The input string must be zero-terminated. A new zero-terminator
+** is added to the dequoted string.
+**
+** The return value is -1 if no dequoting occurs or the length of the
+** dequoted string, exclusive of the zero terminator, if dequoting does
+** occur.
+**
+** 2002-02-14: This routine is extended to remove MS-Access style
+** brackets from around identifiers. For example: "[a-b-c]" becomes
+** "a-b-c".
+*/
+void sqlite3Dequote(char *z){
+ char quote;
+ int i, j;
+ if( z==0 ) return;
+ quote = z[0];
+ if( !sqlite3Isquote(quote) ) return;
+ if( quote=='[' ) quote = ']';
+ for(i=1, j=0;; i++){
+ assert( z[i] );
+ if( z[i]==quote ){
+ if( z[i+1]==quote ){
+ z[j++] = quote;
+ i++;
+ }else{
+ break;
+ }
+ }else{
+ z[j++] = z[i];
+ }
+ }
+ z[j] = 0;
+}
+void sqlite3DequoteExpr(Expr *p){
+ assert( !ExprHasProperty(p, EP_IntValue) );
+ assert( sqlite3Isquote(p->u.zToken[0]) );
+ p->flags |= p->u.zToken[0]=='"' ? EP_Quoted|EP_DblQuoted : EP_Quoted;
+ sqlite3Dequote(p->u.zToken);
+}
+
+/*
+** If the input token p is quoted, try to adjust the token to remove
+** the quotes. This is not always possible:
+**
+** "abc" -> abc
+** "ab""cd" -> (not possible because of the interior "")
+**
+** Remove the quotes if possible. This is a optimization. The overall
+** system should still return the correct answer even if this routine
+** is always a no-op.
+*/
+void sqlite3DequoteToken(Token *p){
+ unsigned int i;
+ if( p->n<2 ) return;
+ if( !sqlite3Isquote(p->z[0]) ) return;
+ for(i=1; i<p->n-1; i++){
+ if( sqlite3Isquote(p->z[i]) ) return;
+ }
+ p->n -= 2;
+ p->z++;
+}
+
+/*
+** Generate a Token object from a string
+*/
+void sqlite3TokenInit(Token *p, char *z){
+ p->z = z;
+ p->n = sqlite3Strlen30(z);
+}
+
+/* Convenient short-hand */
+#define UpperToLower sqlite3UpperToLower
+
+/*
+** Some systems have stricmp(). Others have strcasecmp(). Because
+** there is no consistency, we will define our own.
+**
+** IMPLEMENTATION-OF: R-30243-02494 The sqlite3_stricmp() and
+** sqlite3_strnicmp() APIs allow applications and extensions to compare
+** the contents of two buffers containing UTF-8 strings in a
+** case-independent fashion, using the same definition of "case
+** independence" that SQLite uses internally when comparing identifiers.
+*/
+int sqlite3_stricmp(const char *zLeft, const char *zRight){
+ if( zLeft==0 ){
+ return zRight ? -1 : 0;
+ }else if( zRight==0 ){
+ return 1;
+ }
+ return sqlite3StrICmp(zLeft, zRight);
+}
+int sqlite3StrICmp(const char *zLeft, const char *zRight){
+ unsigned char *a, *b;
+ int c, x;
+ a = (unsigned char *)zLeft;
+ b = (unsigned char *)zRight;
+ for(;;){
+ c = *a;
+ x = *b;
+ if( c==x ){
+ if( c==0 ) break;
+ }else{
+ c = (int)UpperToLower[c] - (int)UpperToLower[x];
+ if( c ) break;
+ }
+ a++;
+ b++;
+ }
+ return c;
+}
+int sqlite3_strnicmp(const char *zLeft, const char *zRight, int N){
+ register unsigned char *a, *b;
+ if( zLeft==0 ){
+ return zRight ? -1 : 0;
+ }else if( zRight==0 ){
+ return 1;
+ }
+ a = (unsigned char *)zLeft;
+ b = (unsigned char *)zRight;
+ while( N-- > 0 && *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
+ return N<0 ? 0 : UpperToLower[*a] - UpperToLower[*b];
+}
+
+/*
+** Compute an 8-bit hash on a string that is insensitive to case differences
+*/
+u8 sqlite3StrIHash(const char *z){
+ u8 h = 0;
+ if( z==0 ) return 0;
+ while( z[0] ){
+ h += UpperToLower[(unsigned char)z[0]];
+ z++;
+ }
+ return h;
+}
+
+/*
+** Compute 10 to the E-th power. Examples: E==1 results in 10.
+** E==2 results in 100. E==50 results in 1.0e50.
+**
+** This routine only works for values of E between 1 and 341.
+*/
+static LONGDOUBLE_TYPE sqlite3Pow10(int E){
+#if defined(_MSC_VER)
+ static const LONGDOUBLE_TYPE x[] = {
+ 1.0e+001L,
+ 1.0e+002L,
+ 1.0e+004L,
+ 1.0e+008L,
+ 1.0e+016L,
+ 1.0e+032L,
+ 1.0e+064L,
+ 1.0e+128L,
+ 1.0e+256L
+ };
+ LONGDOUBLE_TYPE r = 1.0;
+ int i;
+ assert( E>=0 && E<=307 );
+ for(i=0; E!=0; i++, E >>=1){
+ if( E & 1 ) r *= x[i];
+ }
+ return r;
+#else
+ LONGDOUBLE_TYPE x = 10.0;
+ LONGDOUBLE_TYPE r = 1.0;
+ while(1){
+ if( E & 1 ) r *= x;
+ E >>= 1;
+ if( E==0 ) break;
+ x *= x;
+ }
+ return r;
+#endif
+}
+
+/*
+** The string z[] is an text representation of a real number.
+** Convert this string to a double and write it into *pResult.
+**
+** The string z[] is length bytes in length (bytes, not characters) and
+** uses the encoding enc. The string is not necessarily zero-terminated.
+**
+** Return TRUE if the result is a valid real number (or integer) and FALSE
+** if the string is empty or contains extraneous text. More specifically
+** return
+** 1 => The input string is a pure integer
+** 2 or more => The input has a decimal point or eNNN clause
+** 0 or less => The input string is not a valid number
+** -1 => Not a valid number, but has a valid prefix which
+** includes a decimal point and/or an eNNN clause
+**
+** Valid numbers are in one of these formats:
+**
+** [+-]digits[E[+-]digits]
+** [+-]digits.[digits][E[+-]digits]
+** [+-].digits[E[+-]digits]
+**
+** Leading and trailing whitespace is ignored for the purpose of determining
+** validity.
+**
+** If some prefix of the input string is a valid number, this routine
+** returns FALSE but it still converts the prefix and writes the result
+** into *pResult.
+*/
+#if defined(_MSC_VER)
+#pragma warning(disable : 4756)
+#endif
+int sqlite3AtoF(const char *z, double *pResult, int length, u8 enc){
+#ifndef SQLITE_OMIT_FLOATING_POINT
+ int incr;
+ const char *zEnd;
+ /* sign * significand * (10 ^ (esign * exponent)) */
+ int sign = 1; /* sign of significand */
+ i64 s = 0; /* significand */
+ int d = 0; /* adjust exponent for shifting decimal point */
+ int esign = 1; /* sign of exponent */
+ int e = 0; /* exponent */
+ int eValid = 1; /* True exponent is either not used or is well-formed */
+ double result;
+ int nDigit = 0; /* Number of digits processed */
+ int eType = 1; /* 1: pure integer, 2+: fractional -1 or less: bad UTF16 */
+
+ assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
+ *pResult = 0.0; /* Default return value, in case of an error */
+ if( length==0 ) return 0;
+
+ if( enc==SQLITE_UTF8 ){
+ incr = 1;
+ zEnd = z + length;
+ }else{
+ int i;
+ incr = 2;
+ length &= ~1;
+ assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
+ testcase( enc==SQLITE_UTF16LE );
+ testcase( enc==SQLITE_UTF16BE );
+ for(i=3-enc; i<length && z[i]==0; i+=2){}
+ if( i<length ) eType = -100;
+ zEnd = &z[i^1];
+ z += (enc&1);
+ }
+
+ /* skip leading spaces */
+ while( z<zEnd && sqlite3Isspace(*z) ) z+=incr;
+ if( z>=zEnd ) return 0;
+
+ /* get sign of significand */
+ if( *z=='-' ){
+ sign = -1;
+ z+=incr;
+ }else if( *z=='+' ){
+ z+=incr;
+ }
+
+ /* copy max significant digits to significand */
+ while( z<zEnd && sqlite3Isdigit(*z) ){
+ s = s*10 + (*z - '0');
+ z+=incr; nDigit++;
+ if( s>=((LARGEST_INT64-9)/10) ){
+ /* skip non-significant significand digits
+ ** (increase exponent by d to shift decimal left) */
+ while( z<zEnd && sqlite3Isdigit(*z) ){ z+=incr; d++; }
+ }
+ }
+ if( z>=zEnd ) goto do_atof_calc;
+
+ /* if decimal point is present */
+ if( *z=='.' ){
+ z+=incr;
+ eType++;
+ /* copy digits from after decimal to significand
+ ** (decrease exponent by d to shift decimal right) */
+ while( z<zEnd && sqlite3Isdigit(*z) ){
+ if( s<((LARGEST_INT64-9)/10) ){
+ s = s*10 + (*z - '0');
+ d--;
+ nDigit++;
+ }
+ z+=incr;
+ }
+ }
+ if( z>=zEnd ) goto do_atof_calc;
+
+ /* if exponent is present */
+ if( *z=='e' || *z=='E' ){
+ z+=incr;
+ eValid = 0;
+ eType++;
+
+ /* This branch is needed to avoid a (harmless) buffer overread. The
+ ** special comment alerts the mutation tester that the correct answer
+ ** is obtained even if the branch is omitted */
+ if( z>=zEnd ) goto do_atof_calc; /*PREVENTS-HARMLESS-OVERREAD*/
+
+ /* get sign of exponent */
+ if( *z=='-' ){
+ esign = -1;
+ z+=incr;
+ }else if( *z=='+' ){
+ z+=incr;
+ }
+ /* copy digits to exponent */
+ while( z<zEnd && sqlite3Isdigit(*z) ){
+ e = e<10000 ? (e*10 + (*z - '0')) : 10000;
+ z+=incr;
+ eValid = 1;
+ }
+ }
+
+ /* skip trailing spaces */
+ while( z<zEnd && sqlite3Isspace(*z) ) z+=incr;
+
+do_atof_calc:
+ /* adjust exponent by d, and update sign */
+ e = (e*esign) + d;
+ if( e<0 ) {
+ esign = -1;
+ e *= -1;
+ } else {
+ esign = 1;
+ }
+
+ if( s==0 ) {
+ /* In the IEEE 754 standard, zero is signed. */
+ result = sign<0 ? -(double)0 : (double)0;
+ } else {
+ /* Attempt to reduce exponent.
+ **
+ ** Branches that are not required for the correct answer but which only
+ ** help to obtain the correct answer faster are marked with special
+ ** comments, as a hint to the mutation tester.
+ */
+ while( e>0 ){ /*OPTIMIZATION-IF-TRUE*/
+ if( esign>0 ){
+ if( s>=(LARGEST_INT64/10) ) break; /*OPTIMIZATION-IF-FALSE*/
+ s *= 10;
+ }else{
+ if( s%10!=0 ) break; /*OPTIMIZATION-IF-FALSE*/
+ s /= 10;
+ }
+ e--;
+ }
+
+ /* adjust the sign of significand */
+ s = sign<0 ? -s : s;
+
+ if( e==0 ){ /*OPTIMIZATION-IF-TRUE*/
+ result = (double)s;
+ }else{
+ /* attempt to handle extremely small/large numbers better */
+ if( e>307 ){ /*OPTIMIZATION-IF-TRUE*/
+ if( e<342 ){ /*OPTIMIZATION-IF-TRUE*/
+ LONGDOUBLE_TYPE scale = sqlite3Pow10(e-308);
+ if( esign<0 ){
+ result = s / scale;
+ result /= 1.0e+308;
+ }else{
+ result = s * scale;
+ result *= 1.0e+308;
+ }
+ }else{ assert( e>=342 );
+ if( esign<0 ){
+ result = 0.0*s;
+ }else{
+#ifdef INFINITY
+ result = INFINITY*s;
+#else
+ result = 1e308*1e308*s; /* Infinity */
+#endif
+ }
+ }
+ }else{
+ LONGDOUBLE_TYPE scale = sqlite3Pow10(e);
+ if( esign<0 ){
+ result = s / scale;
+ }else{
+ result = s * scale;
+ }
+ }
+ }
+ }
+
+ /* store the result */
+ *pResult = result;
+
+ /* return true if number and no extra non-whitespace chracters after */
+ if( z==zEnd && nDigit>0 && eValid && eType>0 ){
+ return eType;
+ }else if( eType>=2 && (eType==3 || eValid) && nDigit>0 ){
+ return -1;
+ }else{
+ return 0;
+ }
+#else
+ return !sqlite3Atoi64(z, pResult, length, enc);
+#endif /* SQLITE_OMIT_FLOATING_POINT */
+}
+#if defined(_MSC_VER)
+#pragma warning(default : 4756)
+#endif
+
+/*
+** Render an signed 64-bit integer as text. Store the result in zOut[].
+**
+** The caller must ensure that zOut[] is at least 21 bytes in size.
+*/
+void sqlite3Int64ToText(i64 v, char *zOut){
+ int i;
+ u64 x;
+ char zTemp[22];
+ if( v<0 ){
+ x = (v==SMALLEST_INT64) ? ((u64)1)<<63 : (u64)-v;
+ }else{
+ x = v;
+ }
+ i = sizeof(zTemp)-2;
+ zTemp[sizeof(zTemp)-1] = 0;
+ do{
+ zTemp[i--] = (x%10) + '0';
+ x = x/10;
+ }while( x );
+ if( v<0 ) zTemp[i--] = '-';
+ memcpy(zOut, &zTemp[i+1], sizeof(zTemp)-1-i);
+}
+
+/*
+** Compare the 19-character string zNum against the text representation
+** value 2^63: 9223372036854775808. Return negative, zero, or positive
+** if zNum is less than, equal to, or greater than the string.
+** Note that zNum must contain exactly 19 characters.
+**
+** Unlike memcmp() this routine is guaranteed to return the difference
+** in the values of the last digit if the only difference is in the
+** last digit. So, for example,
+**
+** compare2pow63("9223372036854775800", 1)
+**
+** will return -8.
+*/
+static int compare2pow63(const char *zNum, int incr){
+ int c = 0;
+ int i;
+ /* 012345678901234567 */
+ const char *pow63 = "922337203685477580";
+ for(i=0; c==0 && i<18; i++){
+ c = (zNum[i*incr]-pow63[i])*10;
+ }
+ if( c==0 ){
+ c = zNum[18*incr] - '8';
+ testcase( c==(-1) );
+ testcase( c==0 );
+ testcase( c==(+1) );
+ }
+ return c;
+}
+
+/*
+** Convert zNum to a 64-bit signed integer. zNum must be decimal. This
+** routine does *not* accept hexadecimal notation.
+**
+** Returns:
+**
+** -1 Not even a prefix of the input text looks like an integer
+** 0 Successful transformation. Fits in a 64-bit signed integer.
+** 1 Excess non-space text after the integer value
+** 2 Integer too large for a 64-bit signed integer or is malformed
+** 3 Special case of 9223372036854775808
+**
+** length is the number of bytes in the string (bytes, not characters).
+** The string is not necessarily zero-terminated. The encoding is
+** given by enc.
+*/
+int sqlite3Atoi64(const char *zNum, i64 *pNum, int length, u8 enc){
+ int incr;
+ u64 u = 0;
+ int neg = 0; /* assume positive */
+ int i;
+ int c = 0;
+ int nonNum = 0; /* True if input contains UTF16 with high byte non-zero */
+ int rc; /* Baseline return code */
+ const char *zStart;
+ const char *zEnd = zNum + length;
+ assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
+ if( enc==SQLITE_UTF8 ){
+ incr = 1;
+ }else{
+ incr = 2;
+ length &= ~1;
+ assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
+ for(i=3-enc; i<length && zNum[i]==0; i+=2){}
+ nonNum = i<length;
+ zEnd = &zNum[i^1];
+ zNum += (enc&1);
+ }
+ while( zNum<zEnd && sqlite3Isspace(*zNum) ) zNum+=incr;
+ if( zNum<zEnd ){
+ if( *zNum=='-' ){
+ neg = 1;
+ zNum+=incr;
+ }else if( *zNum=='+' ){
+ zNum+=incr;
+ }
+ }
+ zStart = zNum;
+ while( zNum<zEnd && zNum[0]=='0' ){ zNum+=incr; } /* Skip leading zeros. */
+ for(i=0; &zNum[i]<zEnd && (c=zNum[i])>='0' && c<='9'; i+=incr){
+ u = u*10 + c - '0';
+ }
+ testcase( i==18*incr );
+ testcase( i==19*incr );
+ testcase( i==20*incr );
+ if( u>LARGEST_INT64 ){
+ /* This test and assignment is needed only to suppress UB warnings
+ ** from clang and -fsanitize=undefined. This test and assignment make
+ ** the code a little larger and slower, and no harm comes from omitting
+ ** them, but we must appaise the undefined-behavior pharisees. */
+ *pNum = neg ? SMALLEST_INT64 : LARGEST_INT64;
+ }else if( neg ){
+ *pNum = -(i64)u;
+ }else{
+ *pNum = (i64)u;
+ }
+ rc = 0;
+ if( i==0 && zStart==zNum ){ /* No digits */
+ rc = -1;
+ }else if( nonNum ){ /* UTF16 with high-order bytes non-zero */
+ rc = 1;
+ }else if( &zNum[i]<zEnd ){ /* Extra bytes at the end */
+ int jj = i;
+ do{
+ if( !sqlite3Isspace(zNum[jj]) ){
+ rc = 1; /* Extra non-space text after the integer */
+ break;
+ }
+ jj += incr;
+ }while( &zNum[jj]<zEnd );
+ }
+ if( i<19*incr ){
+ /* Less than 19 digits, so we know that it fits in 64 bits */
+ assert( u<=LARGEST_INT64 );
+ return rc;
+ }else{
+ /* zNum is a 19-digit numbers. Compare it against 9223372036854775808. */
+ c = i>19*incr ? 1 : compare2pow63(zNum, incr);
+ if( c<0 ){
+ /* zNum is less than 9223372036854775808 so it fits */
+ assert( u<=LARGEST_INT64 );
+ return rc;
+ }else{
+ *pNum = neg ? SMALLEST_INT64 : LARGEST_INT64;
+ if( c>0 ){
+ /* zNum is greater than 9223372036854775808 so it overflows */
+ return 2;
+ }else{
+ /* zNum is exactly 9223372036854775808. Fits if negative. The
+ ** special case 2 overflow if positive */
+ assert( u-1==LARGEST_INT64 );
+ return neg ? rc : 3;
+ }
+ }
+ }
+}
+
+/*
+** Transform a UTF-8 integer literal, in either decimal or hexadecimal,
+** into a 64-bit signed integer. This routine accepts hexadecimal literals,
+** whereas sqlite3Atoi64() does not.
+**
+** Returns:
+**
+** 0 Successful transformation. Fits in a 64-bit signed integer.
+** 1 Excess text after the integer value
+** 2 Integer too large for a 64-bit signed integer or is malformed
+** 3 Special case of 9223372036854775808
+*/
+int sqlite3DecOrHexToI64(const char *z, i64 *pOut){
+#ifndef SQLITE_OMIT_HEX_INTEGER
+ if( z[0]=='0'
+ && (z[1]=='x' || z[1]=='X')
+ ){
+ u64 u = 0;
+ int i, k;
+ for(i=2; z[i]=='0'; i++){}
+ for(k=i; sqlite3Isxdigit(z[k]); k++){
+ u = u*16 + sqlite3HexToInt(z[k]);
+ }
+ memcpy(pOut, &u, 8);
+ return (z[k]==0 && k-i<=16) ? 0 : 2;
+ }else
+#endif /* SQLITE_OMIT_HEX_INTEGER */
+ {
+ return sqlite3Atoi64(z, pOut, sqlite3Strlen30(z), SQLITE_UTF8);
+ }
+}
+
+/*
+** If zNum represents an integer that will fit in 32-bits, then set
+** *pValue to that integer and return true. Otherwise return false.
+**
+** This routine accepts both decimal and hexadecimal notation for integers.
+**
+** Any non-numeric characters that following zNum are ignored.
+** This is different from sqlite3Atoi64() which requires the
+** input number to be zero-terminated.
+*/
+int sqlite3GetInt32(const char *zNum, int *pValue){
+ sqlite_int64 v = 0;
+ int i, c;
+ int neg = 0;
+ if( zNum[0]=='-' ){
+ neg = 1;
+ zNum++;
+ }else if( zNum[0]=='+' ){
+ zNum++;
+ }
+#ifndef SQLITE_OMIT_HEX_INTEGER
+ else if( zNum[0]=='0'
+ && (zNum[1]=='x' || zNum[1]=='X')
+ && sqlite3Isxdigit(zNum[2])
+ ){
+ u32 u = 0;
+ zNum += 2;
+ while( zNum[0]=='0' ) zNum++;
+ for(i=0; sqlite3Isxdigit(zNum[i]) && i<8; i++){
+ u = u*16 + sqlite3HexToInt(zNum[i]);
+ }
+ if( (u&0x80000000)==0 && sqlite3Isxdigit(zNum[i])==0 ){
+ memcpy(pValue, &u, 4);
+ return 1;
+ }else{
+ return 0;
+ }
+ }
+#endif
+ if( !sqlite3Isdigit(zNum[0]) ) return 0;
+ while( zNum[0]=='0' ) zNum++;
+ for(i=0; i<11 && (c = zNum[i] - '0')>=0 && c<=9; i++){
+ v = v*10 + c;
+ }
+
+ /* The longest decimal representation of a 32 bit integer is 10 digits:
+ **
+ ** 1234567890
+ ** 2^31 -> 2147483648
+ */
+ testcase( i==10 );
+ if( i>10 ){
+ return 0;
+ }
+ testcase( v-neg==2147483647 );
+ if( v-neg>2147483647 ){
+ return 0;
+ }
+ if( neg ){
+ v = -v;
+ }
+ *pValue = (int)v;
+ return 1;
+}
+
+/*
+** Return a 32-bit integer value extracted from a string. If the
+** string is not an integer, just return 0.
+*/
+int sqlite3Atoi(const char *z){
+ int x = 0;
+ sqlite3GetInt32(z, &x);
+ return x;
+}
+
+/*
+** Try to convert z into an unsigned 32-bit integer. Return true on
+** success and false if there is an error.
+**
+** Only decimal notation is accepted.
+*/
+int sqlite3GetUInt32(const char *z, u32 *pI){
+ u64 v = 0;
+ int i;
+ for(i=0; sqlite3Isdigit(z[i]); i++){
+ v = v*10 + z[i] - '0';
+ if( v>4294967296LL ){ *pI = 0; return 0; }
+ }
+ if( i==0 || z[i]!=0 ){ *pI = 0; return 0; }
+ *pI = (u32)v;
+ return 1;
+}
+
+/*
+** The variable-length integer encoding is as follows:
+**
+** KEY:
+** A = 0xxxxxxx 7 bits of data and one flag bit
+** B = 1xxxxxxx 7 bits of data and one flag bit
+** C = xxxxxxxx 8 bits of data
+**
+** 7 bits - A
+** 14 bits - BA
+** 21 bits - BBA
+** 28 bits - BBBA
+** 35 bits - BBBBA
+** 42 bits - BBBBBA
+** 49 bits - BBBBBBA
+** 56 bits - BBBBBBBA
+** 64 bits - BBBBBBBBC
+*/
+
+/*
+** Write a 64-bit variable-length integer to memory starting at p[0].
+** The length of data write will be between 1 and 9 bytes. The number
+** of bytes written is returned.
+**
+** A variable-length integer consists of the lower 7 bits of each byte
+** for all bytes that have the 8th bit set and one byte with the 8th
+** bit clear. Except, if we get to the 9th byte, it stores the full
+** 8 bits and is the last byte.
+*/
+static int SQLITE_NOINLINE putVarint64(unsigned char *p, u64 v){
+ int i, j, n;
+ u8 buf[10];
+ if( v & (((u64)0xff000000)<<32) ){
+ p[8] = (u8)v;
+ v >>= 8;
+ for(i=7; i>=0; i--){
+ p[i] = (u8)((v & 0x7f) | 0x80);
+ v >>= 7;
+ }
+ return 9;
+ }
+ n = 0;
+ do{
+ buf[n++] = (u8)((v & 0x7f) | 0x80);
+ v >>= 7;
+ }while( v!=0 );
+ buf[0] &= 0x7f;
+ assert( n<=9 );
+ for(i=0, j=n-1; j>=0; j--, i++){
+ p[i] = buf[j];
+ }
+ return n;
+}
+int sqlite3PutVarint(unsigned char *p, u64 v){
+ if( v<=0x7f ){
+ p[0] = v&0x7f;
+ return 1;
+ }
+ if( v<=0x3fff ){
+ p[0] = ((v>>7)&0x7f)|0x80;
+ p[1] = v&0x7f;
+ return 2;
+ }
+ return putVarint64(p,v);
+}
+
+/*
+** Bitmasks used by sqlite3GetVarint(). These precomputed constants
+** are defined here rather than simply putting the constant expressions
+** inline in order to work around bugs in the RVT compiler.
+**
+** SLOT_2_0 A mask for (0x7f<<14) | 0x7f
+**
+** SLOT_4_2_0 A mask for (0x7f<<28) | SLOT_2_0
+*/
+#define SLOT_2_0 0x001fc07f
+#define SLOT_4_2_0 0xf01fc07f
+
+
+/*
+** Read a 64-bit variable-length integer from memory starting at p[0].
+** Return the number of bytes read. The value is stored in *v.
+*/
+u8 sqlite3GetVarint(const unsigned char *p, u64 *v){
+ u32 a,b,s;
+
+ if( ((signed char*)p)[0]>=0 ){
+ *v = *p;
+ return 1;
+ }
+ if( ((signed char*)p)[1]>=0 ){
+ *v = ((u32)(p[0]&0x7f)<<7) | p[1];
+ return 2;
+ }
+
+ /* Verify that constants are precomputed correctly */
+ assert( SLOT_2_0 == ((0x7f<<14) | (0x7f)) );
+ assert( SLOT_4_2_0 == ((0xfU<<28) | (0x7f<<14) | (0x7f)) );
+
+ a = ((u32)p[0])<<14;
+ b = p[1];
+ p += 2;
+ a |= *p;
+ /* a: p0<<14 | p2 (unmasked) */
+ if (!(a&0x80))
+ {
+ a &= SLOT_2_0;
+ b &= 0x7f;
+ b = b<<7;
+ a |= b;
+ *v = a;
+ return 3;
+ }
+
+ /* CSE1 from below */
+ a &= SLOT_2_0;
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p1<<14 | p3 (unmasked) */
+ if (!(b&0x80))
+ {
+ b &= SLOT_2_0;
+ /* moved CSE1 up */
+ /* a &= (0x7f<<14)|(0x7f); */
+ a = a<<7;
+ a |= b;
+ *v = a;
+ return 4;
+ }
+
+ /* a: p0<<14 | p2 (masked) */
+ /* b: p1<<14 | p3 (unmasked) */
+ /* 1:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+ /* moved CSE1 up */
+ /* a &= (0x7f<<14)|(0x7f); */
+ b &= SLOT_2_0;
+ s = a;
+ /* s: p0<<14 | p2 (masked) */
+
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p0<<28 | p2<<14 | p4 (unmasked) */
+ if (!(a&0x80))
+ {
+ /* we can skip these cause they were (effectively) done above
+ ** while calculating s */
+ /* a &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
+ /* b &= (0x7f<<14)|(0x7f); */
+ b = b<<7;
+ a |= b;
+ s = s>>18;
+ *v = ((u64)s)<<32 | a;
+ return 5;
+ }
+
+ /* 2:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+ s = s<<7;
+ s |= b;
+ /* s: p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p1<<28 | p3<<14 | p5 (unmasked) */
+ if (!(b&0x80))
+ {
+ /* we can skip this cause it was (effectively) done above in calc'ing s */
+ /* b &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
+ a &= SLOT_2_0;
+ a = a<<7;
+ a |= b;
+ s = s>>18;
+ *v = ((u64)s)<<32 | a;
+ return 6;
+ }
+
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p2<<28 | p4<<14 | p6 (unmasked) */
+ if (!(a&0x80))
+ {
+ a &= SLOT_4_2_0;
+ b &= SLOT_2_0;
+ b = b<<7;
+ a |= b;
+ s = s>>11;
+ *v = ((u64)s)<<32 | a;
+ return 7;
+ }
+
+ /* CSE2 from below */
+ a &= SLOT_2_0;
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p3<<28 | p5<<14 | p7 (unmasked) */
+ if (!(b&0x80))
+ {
+ b &= SLOT_4_2_0;
+ /* moved CSE2 up */
+ /* a &= (0x7f<<14)|(0x7f); */
+ a = a<<7;
+ a |= b;
+ s = s>>4;
+ *v = ((u64)s)<<32 | a;
+ return 8;
+ }
+
+ p++;
+ a = a<<15;
+ a |= *p;
+ /* a: p4<<29 | p6<<15 | p8 (unmasked) */
+
+ /* moved CSE2 up */
+ /* a &= (0x7f<<29)|(0x7f<<15)|(0xff); */
+ b &= SLOT_2_0;
+ b = b<<8;
+ a |= b;
+
+ s = s<<4;
+ b = p[-4];
+ b &= 0x7f;
+ b = b>>3;
+ s |= b;
+
+ *v = ((u64)s)<<32 | a;
+
+ return 9;
+}
+
+/*
+** Read a 32-bit variable-length integer from memory starting at p[0].
+** Return the number of bytes read. The value is stored in *v.
+**
+** If the varint stored in p[0] is larger than can fit in a 32-bit unsigned
+** integer, then set *v to 0xffffffff.
+**
+** A MACRO version, getVarint32, is provided which inlines the
+** single-byte case. All code should use the MACRO version as
+** this function assumes the single-byte case has already been handled.
+*/
+u8 sqlite3GetVarint32(const unsigned char *p, u32 *v){
+ u32 a,b;
+
+ /* The 1-byte case. Overwhelmingly the most common. Handled inline
+ ** by the getVarin32() macro */
+ a = *p;
+ /* a: p0 (unmasked) */
+#ifndef getVarint32
+ if (!(a&0x80))
+ {
+ /* Values between 0 and 127 */
+ *v = a;
+ return 1;
+ }
+#endif
+
+ /* The 2-byte case */
+ p++;
+ b = *p;
+ /* b: p1 (unmasked) */
+ if (!(b&0x80))
+ {
+ /* Values between 128 and 16383 */
+ a &= 0x7f;
+ a = a<<7;
+ *v = a | b;
+ return 2;
+ }
+
+ /* The 3-byte case */
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p0<<14 | p2 (unmasked) */
+ if (!(a&0x80))
+ {
+ /* Values between 16384 and 2097151 */
+ a &= (0x7f<<14)|(0x7f);
+ b &= 0x7f;
+ b = b<<7;
+ *v = a | b;
+ return 3;
+ }
+
+ /* A 32-bit varint is used to store size information in btrees.
+ ** Objects are rarely larger than 2MiB limit of a 3-byte varint.
+ ** A 3-byte varint is sufficient, for example, to record the size
+ ** of a 1048569-byte BLOB or string.
+ **
+ ** We only unroll the first 1-, 2-, and 3- byte cases. The very
+ ** rare larger cases can be handled by the slower 64-bit varint
+ ** routine.
+ */
+#if 1
+ {
+ u64 v64;
+ u8 n;
+
+ n = sqlite3GetVarint(p-2, &v64);
+ assert( n>3 && n<=9 );
+ if( (v64 & SQLITE_MAX_U32)!=v64 ){
+ *v = 0xffffffff;
+ }else{
+ *v = (u32)v64;
+ }
+ return n;
+ }
+
+#else
+ /* For following code (kept for historical record only) shows an
+ ** unrolling for the 3- and 4-byte varint cases. This code is
+ ** slightly faster, but it is also larger and much harder to test.
+ */
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p1<<14 | p3 (unmasked) */
+ if (!(b&0x80))
+ {
+ /* Values between 2097152 and 268435455 */
+ b &= (0x7f<<14)|(0x7f);
+ a &= (0x7f<<14)|(0x7f);
+ a = a<<7;
+ *v = a | b;
+ return 4;
+ }
+
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p0<<28 | p2<<14 | p4 (unmasked) */
+ if (!(a&0x80))
+ {
+ /* Values between 268435456 and 34359738367 */
+ a &= SLOT_4_2_0;
+ b &= SLOT_4_2_0;
+ b = b<<7;
+ *v = a | b;
+ return 5;
+ }
+
+ /* We can only reach this point when reading a corrupt database
+ ** file. In that case we are not in any hurry. Use the (relatively
+ ** slow) general-purpose sqlite3GetVarint() routine to extract the
+ ** value. */
+ {
+ u64 v64;
+ u8 n;
+
+ p -= 4;
+ n = sqlite3GetVarint(p, &v64);
+ assert( n>5 && n<=9 );
+ *v = (u32)v64;
+ return n;
+ }
+#endif
+}
+
+/*
+** Return the number of bytes that will be needed to store the given
+** 64-bit integer.
+*/
+int sqlite3VarintLen(u64 v){
+ int i;
+ for(i=1; (v >>= 7)!=0; i++){ assert( i<10 ); }
+ return i;
+}
+
+
+/*
+** Read or write a four-byte big-endian integer value.
+*/
+u32 sqlite3Get4byte(const u8 *p){
+#if SQLITE_BYTEORDER==4321
+ u32 x;
+ memcpy(&x,p,4);
+ return x;
+#elif SQLITE_BYTEORDER==1234 && GCC_VERSION>=4003000
+ u32 x;
+ memcpy(&x,p,4);
+ return __builtin_bswap32(x);
+#elif SQLITE_BYTEORDER==1234 && MSVC_VERSION>=1300
+ u32 x;
+ memcpy(&x,p,4);
+ return _byteswap_ulong(x);
+#else
+ testcase( p[0]&0x80 );
+ return ((unsigned)p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3];
+#endif
+}
+void sqlite3Put4byte(unsigned char *p, u32 v){
+#if SQLITE_BYTEORDER==4321
+ memcpy(p,&v,4);
+#elif SQLITE_BYTEORDER==1234 && GCC_VERSION>=4003000
+ u32 x = __builtin_bswap32(v);
+ memcpy(p,&x,4);
+#elif SQLITE_BYTEORDER==1234 && MSVC_VERSION>=1300
+ u32 x = _byteswap_ulong(v);
+ memcpy(p,&x,4);
+#else
+ p[0] = (u8)(v>>24);
+ p[1] = (u8)(v>>16);
+ p[2] = (u8)(v>>8);
+ p[3] = (u8)v;
+#endif
+}
+
+
+
+/*
+** Translate a single byte of Hex into an integer.
+** This routine only works if h really is a valid hexadecimal
+** character: 0..9a..fA..F
+*/
+u8 sqlite3HexToInt(int h){
+ assert( (h>='0' && h<='9') || (h>='a' && h<='f') || (h>='A' && h<='F') );
+#ifdef SQLITE_ASCII
+ h += 9*(1&(h>>6));
+#endif
+#ifdef SQLITE_EBCDIC
+ h += 9*(1&~(h>>4));
+#endif
+ return (u8)(h & 0xf);
+}
+
+#if !defined(SQLITE_OMIT_BLOB_LITERAL)
+/*
+** Convert a BLOB literal of the form "x'hhhhhh'" into its binary
+** value. Return a pointer to its binary value. Space to hold the
+** binary value has been obtained from malloc and must be freed by
+** the calling routine.
+*/
+void *sqlite3HexToBlob(sqlite3 *db, const char *z, int n){
+ char *zBlob;
+ int i;
+
+ zBlob = (char *)sqlite3DbMallocRawNN(db, n/2 + 1);
+ n--;
+ if( zBlob ){
+ for(i=0; i<n; i+=2){
+ zBlob[i/2] = (sqlite3HexToInt(z[i])<<4) | sqlite3HexToInt(z[i+1]);
+ }
+ zBlob[i/2] = 0;
+ }
+ return zBlob;
+}
+#endif /* !SQLITE_OMIT_BLOB_LITERAL */
+
+/*
+** Log an error that is an API call on a connection pointer that should
+** not have been used. The "type" of connection pointer is given as the
+** argument. The zType is a word like "NULL" or "closed" or "invalid".
+*/
+static void logBadConnection(const char *zType){
+ sqlite3_log(SQLITE_MISUSE,
+ "API call with %s database connection pointer",
+ zType
+ );
+}
+
+/*
+** Check to make sure we have a valid db pointer. This test is not
+** foolproof but it does provide some measure of protection against
+** misuse of the interface such as passing in db pointers that are
+** NULL or which have been previously closed. If this routine returns
+** 1 it means that the db pointer is valid and 0 if it should not be
+** dereferenced for any reason. The calling function should invoke
+** SQLITE_MISUSE immediately.
+**
+** sqlite3SafetyCheckOk() requires that the db pointer be valid for
+** use. sqlite3SafetyCheckSickOrOk() allows a db pointer that failed to
+** open properly and is not fit for general use but which can be
+** used as an argument to sqlite3_errmsg() or sqlite3_close().
+*/
+int sqlite3SafetyCheckOk(sqlite3 *db){
+ u8 eOpenState;
+ if( db==0 ){
+ logBadConnection("NULL");
+ return 0;
+ }
+ eOpenState = db->eOpenState;
+ if( eOpenState!=SQLITE_STATE_OPEN ){
+ if( sqlite3SafetyCheckSickOrOk(db) ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ logBadConnection("unopened");
+ }
+ return 0;
+ }else{
+ return 1;
+ }
+}
+int sqlite3SafetyCheckSickOrOk(sqlite3 *db){
+ u8 eOpenState;
+ eOpenState = db->eOpenState;
+ if( eOpenState!=SQLITE_STATE_SICK &&
+ eOpenState!=SQLITE_STATE_OPEN &&
+ eOpenState!=SQLITE_STATE_BUSY ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ logBadConnection("invalid");
+ return 0;
+ }else{
+ return 1;
+ }
+}
+
+/*
+** Attempt to add, substract, or multiply the 64-bit signed value iB against
+** the other 64-bit signed integer at *pA and store the result in *pA.
+** Return 0 on success. Or if the operation would have resulted in an
+** overflow, leave *pA unchanged and return 1.
+*/
+int sqlite3AddInt64(i64 *pA, i64 iB){
+#if GCC_VERSION>=5004000 && !defined(__INTEL_COMPILER)
+ return __builtin_add_overflow(*pA, iB, pA);
+#else
+ i64 iA = *pA;
+ testcase( iA==0 ); testcase( iA==1 );
+ testcase( iB==-1 ); testcase( iB==0 );
+ if( iB>=0 ){
+ testcase( iA>0 && LARGEST_INT64 - iA == iB );
+ testcase( iA>0 && LARGEST_INT64 - iA == iB - 1 );
+ if( iA>0 && LARGEST_INT64 - iA < iB ) return 1;
+ }else{
+ testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 1 );
+ testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 2 );
+ if( iA<0 && -(iA + LARGEST_INT64) > iB + 1 ) return 1;
+ }
+ *pA += iB;
+ return 0;
+#endif
+}
+int sqlite3SubInt64(i64 *pA, i64 iB){
+#if GCC_VERSION>=5004000 && !defined(__INTEL_COMPILER)
+ return __builtin_sub_overflow(*pA, iB, pA);
+#else
+ testcase( iB==SMALLEST_INT64+1 );
+ if( iB==SMALLEST_INT64 ){
+ testcase( (*pA)==(-1) ); testcase( (*pA)==0 );
+ if( (*pA)>=0 ) return 1;
+ *pA -= iB;
+ return 0;
+ }else{
+ return sqlite3AddInt64(pA, -iB);
+ }
+#endif
+}
+int sqlite3MulInt64(i64 *pA, i64 iB){
+#if GCC_VERSION>=5004000 && !defined(__INTEL_COMPILER)
+ return __builtin_mul_overflow(*pA, iB, pA);
+#else
+ i64 iA = *pA;
+ if( iB>0 ){
+ if( iA>LARGEST_INT64/iB ) return 1;
+ if( iA<SMALLEST_INT64/iB ) return 1;
+ }else if( iB<0 ){
+ if( iA>0 ){
+ if( iB<SMALLEST_INT64/iA ) return 1;
+ }else if( iA<0 ){
+ if( iB==SMALLEST_INT64 ) return 1;
+ if( iA==SMALLEST_INT64 ) return 1;
+ if( -iA>LARGEST_INT64/-iB ) return 1;
+ }
+ }
+ *pA = iA*iB;
+ return 0;
+#endif
+}
+
+/*
+** Compute the absolute value of a 32-bit signed integer, of possible. Or
+** if the integer has a value of -2147483648, return +2147483647
+*/
+int sqlite3AbsInt32(int x){
+ if( x>=0 ) return x;
+ if( x==(int)0x80000000 ) return 0x7fffffff;
+ return -x;
+}
+
+#ifdef SQLITE_ENABLE_8_3_NAMES
+/*
+** If SQLITE_ENABLE_8_3_NAMES is set at compile-time and if the database
+** filename in zBaseFilename is a URI with the "8_3_names=1" parameter and
+** if filename in z[] has a suffix (a.k.a. "extension") that is longer than
+** three characters, then shorten the suffix on z[] to be the last three
+** characters of the original suffix.
+**
+** If SQLITE_ENABLE_8_3_NAMES is set to 2 at compile-time, then always
+** do the suffix shortening regardless of URI parameter.
+**
+** Examples:
+**
+** test.db-journal => test.nal
+** test.db-wal => test.wal
+** test.db-shm => test.shm
+** test.db-mj7f3319fa => test.9fa
+*/
+void sqlite3FileSuffix3(const char *zBaseFilename, char *z){
+#if SQLITE_ENABLE_8_3_NAMES<2
+ if( sqlite3_uri_boolean(zBaseFilename, "8_3_names", 0) )
+#endif
+ {
+ int i, sz;
+ sz = sqlite3Strlen30(z);
+ for(i=sz-1; i>0 && z[i]!='/' && z[i]!='.'; i--){}
+ if( z[i]=='.' && ALWAYS(sz>i+4) ) memmove(&z[i+1], &z[sz-3], 4);
+ }
+}
+#endif
+
+/*
+** Find (an approximate) sum of two LogEst values. This computation is
+** not a simple "+" operator because LogEst is stored as a logarithmic
+** value.
+**
+*/
+LogEst sqlite3LogEstAdd(LogEst a, LogEst b){
+ static const unsigned char x[] = {
+ 10, 10, /* 0,1 */
+ 9, 9, /* 2,3 */
+ 8, 8, /* 4,5 */
+ 7, 7, 7, /* 6,7,8 */
+ 6, 6, 6, /* 9,10,11 */
+ 5, 5, 5, /* 12-14 */
+ 4, 4, 4, 4, /* 15-18 */
+ 3, 3, 3, 3, 3, 3, /* 19-24 */
+ 2, 2, 2, 2, 2, 2, 2, /* 25-31 */
+ };
+ if( a>=b ){
+ if( a>b+49 ) return a;
+ if( a>b+31 ) return a+1;
+ return a+x[a-b];
+ }else{
+ if( b>a+49 ) return b;
+ if( b>a+31 ) return b+1;
+ return b+x[b-a];
+ }
+}
+
+/*
+** Convert an integer into a LogEst. In other words, compute an
+** approximation for 10*log2(x).
+*/
+LogEst sqlite3LogEst(u64 x){
+ static LogEst a[] = { 0, 2, 3, 5, 6, 7, 8, 9 };
+ LogEst y = 40;
+ if( x<8 ){
+ if( x<2 ) return 0;
+ while( x<8 ){ y -= 10; x <<= 1; }
+ }else{
+#if GCC_VERSION>=5004000
+ int i = 60 - __builtin_clzll(x);
+ y += i*10;
+ x >>= i;
+#else
+ while( x>255 ){ y += 40; x >>= 4; } /*OPTIMIZATION-IF-TRUE*/
+ while( x>15 ){ y += 10; x >>= 1; }
+#endif
+ }
+ return a[x&7] + y - 10;
+}
+
+/*
+** Convert a double into a LogEst
+** In other words, compute an approximation for 10*log2(x).
+*/
+LogEst sqlite3LogEstFromDouble(double x){
+ u64 a;
+ LogEst e;
+ assert( sizeof(x)==8 && sizeof(a)==8 );
+ if( x<=1 ) return 0;
+ if( x<=2000000000 ) return sqlite3LogEst((u64)x);
+ memcpy(&a, &x, 8);
+ e = (a>>52) - 1022;
+ return e*10;
+}
+
+/*
+** Convert a LogEst into an integer.
+*/
+u64 sqlite3LogEstToInt(LogEst x){
+ u64 n;
+ n = x%10;
+ x /= 10;
+ if( n>=5 ) n -= 2;
+ else if( n>=1 ) n -= 1;
+ if( x>60 ) return (u64)LARGEST_INT64;
+ return x>=3 ? (n+8)<<(x-3) : (n+8)>>(3-x);
+}
+
+/*
+** Add a new name/number pair to a VList. This might require that the
+** VList object be reallocated, so return the new VList. If an OOM
+** error occurs, the original VList returned and the
+** db->mallocFailed flag is set.
+**
+** A VList is really just an array of integers. To destroy a VList,
+** simply pass it to sqlite3DbFree().
+**
+** The first integer is the number of integers allocated for the whole
+** VList. The second integer is the number of integers actually used.
+** Each name/number pair is encoded by subsequent groups of 3 or more
+** integers.
+**
+** Each name/number pair starts with two integers which are the numeric
+** value for the pair and the size of the name/number pair, respectively.
+** The text name overlays one or more following integers. The text name
+** is always zero-terminated.
+**
+** Conceptually:
+**
+** struct VList {
+** int nAlloc; // Number of allocated slots
+** int nUsed; // Number of used slots
+** struct VListEntry {
+** int iValue; // Value for this entry
+** int nSlot; // Slots used by this entry
+** // ... variable name goes here
+** } a[0];
+** }
+**
+** During code generation, pointers to the variable names within the
+** VList are taken. When that happens, nAlloc is set to zero as an
+** indication that the VList may never again be enlarged, since the
+** accompanying realloc() would invalidate the pointers.
+*/
+VList *sqlite3VListAdd(
+ sqlite3 *db, /* The database connection used for malloc() */
+ VList *pIn, /* The input VList. Might be NULL */
+ const char *zName, /* Name of symbol to add */
+ int nName, /* Bytes of text in zName */
+ int iVal /* Value to associate with zName */
+){
+ int nInt; /* number of sizeof(int) objects needed for zName */
+ char *z; /* Pointer to where zName will be stored */
+ int i; /* Index in pIn[] where zName is stored */
+
+ nInt = nName/4 + 3;
+ assert( pIn==0 || pIn[0]>=3 ); /* Verify ok to add new elements */
+ if( pIn==0 || pIn[1]+nInt > pIn[0] ){
+ /* Enlarge the allocation */
+ sqlite3_int64 nAlloc = (pIn ? 2*(sqlite3_int64)pIn[0] : 10) + nInt;
+ VList *pOut = sqlite3DbRealloc(db, pIn, nAlloc*sizeof(int));
+ if( pOut==0 ) return pIn;
+ if( pIn==0 ) pOut[1] = 2;
+ pIn = pOut;
+ pIn[0] = nAlloc;
+ }
+ i = pIn[1];
+ pIn[i] = iVal;
+ pIn[i+1] = nInt;
+ z = (char*)&pIn[i+2];
+ pIn[1] = i+nInt;
+ assert( pIn[1]<=pIn[0] );
+ memcpy(z, zName, nName);
+ z[nName] = 0;
+ return pIn;
+}
+
+/*
+** Return a pointer to the name of a variable in the given VList that
+** has the value iVal. Or return a NULL if there is no such variable in
+** the list
+*/
+const char *sqlite3VListNumToName(VList *pIn, int iVal){
+ int i, mx;
+ if( pIn==0 ) return 0;
+ mx = pIn[1];
+ i = 2;
+ do{
+ if( pIn[i]==iVal ) return (char*)&pIn[i+2];
+ i += pIn[i+1];
+ }while( i<mx );
+ return 0;
+}
+
+/*
+** Return the number of the variable named zName, if it is in VList.
+** or return 0 if there is no such variable.
+*/
+int sqlite3VListNameToNum(VList *pIn, const char *zName, int nName){
+ int i, mx;
+ if( pIn==0 ) return 0;
+ mx = pIn[1];
+ i = 2;
+ do{
+ const char *z = (const char*)&pIn[i+2];
+ if( strncmp(z,zName,nName)==0 && z[nName]==0 ) return pIn[i];
+ i += pIn[i+1];
+ }while( i<mx );
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-11 02:33:42 +0000