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authorTimothy Pearson <[email protected]>2011-11-08 12:31:36 -0600
committerTimothy Pearson <[email protected]>2011-11-08 12:31:36 -0600
commitd796c9dd933ab96ec83b9a634feedd5d32e1ba3f (patch)
tree6e3dcca4f77e20ec8966c666aac7c35bd4704053 /src/3rdparty/sqlite/util.c
downloadtqt3-d796c9dd933ab96ec83b9a634feedd5d32e1ba3f.tar.gz
tqt3-d796c9dd933ab96ec83b9a634feedd5d32e1ba3f.zip
Test conversion to TQt3 from Qt3 8c6fc1f8e35fd264dd01c582ca5e7549b32ab731
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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.
+**
+** $Id: util.c,v 1.74 2004/02/22 17:49:34 drh Exp $
+*/
+#include "sqliteInt.h"
+#include <stdarg.h>
+#include <ctype.h>
+
+/*
+** If malloc() ever fails, this global variable gets set to 1.
+** This causes the library to abort and never again function.
+*/
+int sqlite_malloc_failed = 0;
+
+/*
+** If MEMORY_DEBUG is defined, then use versions of malloc() and
+** free() that track memory usage and check for buffer overruns.
+*/
+#ifdef MEMORY_DEBUG
+
+/*
+** For keeping track of the number of mallocs and frees. This
+** is used to check for memory leaks.
+*/
+int sqlite_nMalloc; /* Number of sqliteMalloc() calls */
+int sqlite_nFree; /* Number of sqliteFree() calls */
+int sqlite_iMallocFail; /* Fail sqliteMalloc() after this many calls */
+#if MEMORY_DEBUG>1
+static int memcnt = 0;
+#endif
+
+/*
+** Number of 32-bit guard words
+*/
+#define N_GUARD 1
+
+/*
+** Allocate new memory and set it to zero. Return NULL if
+** no memory is available.
+*/
+void *sqliteMalloc_(int n, int bZero, char *zFile, int line){
+ void *p;
+ int *pi;
+ int i, k;
+ if( sqlite_iMallocFail>=0 ){
+ sqlite_iMallocFail--;
+ if( sqlite_iMallocFail==0 ){
+ sqlite_malloc_failed++;
+#if MEMORY_DEBUG>1
+ fprintf(stderr,"**** failed to allocate %d bytes at %s:%d\n",
+ n, zFile,line);
+#endif
+ sqlite_iMallocFail--;
+ return 0;
+ }
+ }
+ if( n==0 ) return 0;
+ k = (n+sizeof(int)-1)/sizeof(int);
+ pi = malloc( (N_GUARD*2+1+k)*sizeof(int));
+ if( pi==0 ){
+ sqlite_malloc_failed++;
+ return 0;
+ }
+ sqlite_nMalloc++;
+ for(i=0; i<N_GUARD; i++) pi[i] = 0xdead1122;
+ pi[N_GUARD] = n;
+ for(i=0; i<N_GUARD; i++) pi[k+1+N_GUARD+i] = 0xdead3344;
+ p = &pi[N_GUARD+1];
+ memset(p, bZero==0, n);
+#if MEMORY_DEBUG>1
+ fprintf(stderr,"%06d malloc %d bytes at 0x%x from %s:%d\n",
+ ++memcnt, n, (int)p, zFile,line);
+#endif
+ return p;
+}
+
+/*
+** Check to see if the given pointer was obtained from sqliteMalloc()
+** and is able to hold at least N bytes. Raise an exception if this
+** is not the case.
+**
+** This routine is used for testing purposes only.
+*/
+void sqliteCheckMemory(void *p, int N){
+ int *pi = p;
+ int n, i, k;
+ pi -= N_GUARD+1;
+ for(i=0; i<N_GUARD; i++){
+ assert( pi[i]==0xdead1122 );
+ }
+ n = pi[N_GUARD];
+ assert( N>=0 && N<n );
+ k = (n+sizeof(int)-1)/sizeof(int);
+ for(i=0; i<N_GUARD; i++){
+ assert( pi[k+N_GUARD+1+i]==0xdead3344 );
+ }
+}
+
+/*
+** Free memory previously obtained from sqliteMalloc()
+*/
+void sqliteFree_(void *p, char *zFile, int line){
+ if( p ){
+ int *pi, i, k, n;
+ pi = p;
+ pi -= N_GUARD+1;
+ sqlite_nFree++;
+ for(i=0; i<N_GUARD; i++){
+ if( pi[i]!=0xdead1122 ){
+ fprintf(stderr,"Low-end memory corruption at 0x%x\n", (int)p);
+ return;
+ }
+ }
+ n = pi[N_GUARD];
+ k = (n+sizeof(int)-1)/sizeof(int);
+ for(i=0; i<N_GUARD; i++){
+ if( pi[k+N_GUARD+1+i]!=0xdead3344 ){
+ fprintf(stderr,"High-end memory corruption at 0x%x\n", (int)p);
+ return;
+ }
+ }
+ memset(pi, 0xff, (k+N_GUARD*2+1)*sizeof(int));
+#if MEMORY_DEBUG>1
+ fprintf(stderr,"%06d free %d bytes at 0x%x from %s:%d\n",
+ ++memcnt, n, (int)p, zFile,line);
+#endif
+ free(pi);
+ }
+}
+
+/*
+** Resize a prior allocation. If p==0, then this routine
+** works just like sqliteMalloc(). If n==0, then this routine
+** works just like sqliteFree().
+*/
+void *sqliteRealloc_(void *oldP, int n, char *zFile, int line){
+ int *oldPi, *pi, i, k, oldN, oldK;
+ void *p;
+ if( oldP==0 ){
+ return sqliteMalloc_(n,1,zFile,line);
+ }
+ if( n==0 ){
+ sqliteFree_(oldP,zFile,line);
+ return 0;
+ }
+ oldPi = oldP;
+ oldPi -= N_GUARD+1;
+ if( oldPi[0]!=0xdead1122 ){
+ fprintf(stderr,"Low-end memory corruption in realloc at 0x%x\n", (int)oldP);
+ return 0;
+ }
+ oldN = oldPi[N_GUARD];
+ oldK = (oldN+sizeof(int)-1)/sizeof(int);
+ for(i=0; i<N_GUARD; i++){
+ if( oldPi[oldK+N_GUARD+1+i]!=0xdead3344 ){
+ fprintf(stderr,"High-end memory corruption in realloc at 0x%x\n",
+ (int)oldP);
+ return 0;
+ }
+ }
+ k = (n + sizeof(int) - 1)/sizeof(int);
+ pi = malloc( (k+N_GUARD*2+1)*sizeof(int) );
+ if( pi==0 ){
+ sqlite_malloc_failed++;
+ return 0;
+ }
+ for(i=0; i<N_GUARD; i++) pi[i] = 0xdead1122;
+ pi[N_GUARD] = n;
+ for(i=0; i<N_GUARD; i++) pi[k+N_GUARD+1+i] = 0xdead3344;
+ p = &pi[N_GUARD+1];
+ memcpy(p, oldP, n>oldN ? oldN : n);
+ if( n>oldN ){
+ memset(&((char*)p)[oldN], 0, n-oldN);
+ }
+ memset(oldPi, 0xab, (oldK+N_GUARD+2)*sizeof(int));
+ free(oldPi);
+#if MEMORY_DEBUG>1
+ fprintf(stderr,"%06d realloc %d to %d bytes at 0x%x to 0x%x at %s:%d\n",
+ ++memcnt, oldN, n, (int)oldP, (int)p, zFile, line);
+#endif
+ return p;
+}
+
+/*
+** Make a duplicate of a string into memory obtained from malloc()
+** Free the original string using sqliteFree().
+**
+** This routine is called on all strings that are passed outside of
+** the SQLite library. That way clients can free the string using free()
+** rather than having to call sqliteFree().
+*/
+void sqliteStrRealloc(char **pz){
+ char *zNew;
+ if( pz==0 || *pz==0 ) return;
+ zNew = malloc( strlen(*pz) + 1 );
+ if( zNew==0 ){
+ sqlite_malloc_failed++;
+ sqliteFree(*pz);
+ *pz = 0;
+ }
+ strcpy(zNew, *pz);
+ sqliteFree(*pz);
+ *pz = zNew;
+}
+
+/*
+** Make a copy of a string in memory obtained from sqliteMalloc()
+*/
+char *sqliteStrDup_(const char *z, char *zFile, int line){
+ char *zNew;
+ if( z==0 ) return 0;
+ zNew = sqliteMalloc_(strlen(z)+1, 0, zFile, line);
+ if( zNew ) strcpy(zNew, z);
+ return zNew;
+}
+char *sqliteStrNDup_(const char *z, int n, char *zFile, int line){
+ char *zNew;
+ if( z==0 ) return 0;
+ zNew = sqliteMalloc_(n+1, 0, zFile, line);
+ if( zNew ){
+ memcpy(zNew, z, n);
+ zNew[n] = 0;
+ }
+ return zNew;
+}
+#endif /* MEMORY_DEBUG */
+
+/*
+** The following versions of malloc() and free() are for use in a
+** normal build.
+*/
+#if !defined(MEMORY_DEBUG)
+
+/*
+** Allocate new memory and set it to zero. Return NULL if
+** no memory is available. See also sqliteMallocRaw().
+*/
+void *sqliteMalloc(int n){
+ void *p;
+ if( (p = malloc(n))==0 ){
+ if( n>0 ) sqlite_malloc_failed++;
+ }else{
+ memset(p, 0, n);
+ }
+ return p;
+}
+
+/*
+** Allocate new memory but do not set it to zero. Return NULL if
+** no memory is available. See also sqliteMalloc().
+*/
+void *sqliteMallocRaw(int n){
+ void *p;
+ if( (p = malloc(n))==0 ){
+ if( n>0 ) sqlite_malloc_failed++;
+ }
+ return p;
+}
+
+/*
+** Free memory previously obtained from sqliteMalloc()
+*/
+void sqliteFree(void *p){
+ if( p ){
+ free(p);
+ }
+}
+
+/*
+** Resize a prior allocation. If p==0, then this routine
+** works just like sqliteMalloc(). If n==0, then this routine
+** works just like sqliteFree().
+*/
+void *sqliteRealloc(void *p, int n){
+ void *p2;
+ if( p==0 ){
+ return sqliteMalloc(n);
+ }
+ if( n==0 ){
+ sqliteFree(p);
+ return 0;
+ }
+ p2 = realloc(p, n);
+ if( p2==0 ){
+ sqlite_malloc_failed++;
+ }
+ return p2;
+}
+
+/*
+** Make a copy of a string in memory obtained from sqliteMalloc()
+*/
+char *sqliteStrDup(const char *z){
+ char *zNew;
+ if( z==0 ) return 0;
+ zNew = sqliteMallocRaw(strlen(z)+1);
+ if( zNew ) strcpy(zNew, z);
+ return zNew;
+}
+char *sqliteStrNDup(const char *z, int n){
+ char *zNew;
+ if( z==0 ) return 0;
+ zNew = sqliteMallocRaw(n+1);
+ if( zNew ){
+ memcpy(zNew, z, n);
+ zNew[n] = 0;
+ }
+ return zNew;
+}
+#endif /* !defined(MEMORY_DEBUG) */
+
+/*
+** Create a string from the 2nd and subsequent arguments (up to the
+** first NULL argument), store the string in memory obtained from
+** sqliteMalloc() and make the pointer indicated by the 1st argument
+** point to that string. The 1st argument must either be NULL or
+** point to memory obtained from sqliteMalloc().
+*/
+void sqliteSetString(char **pz, const char *zFirst, ...){
+ va_list ap;
+ int nByte;
+ const char *z;
+ char *zResult;
+
+ if( pz==0 ) return;
+ nByte = strlen(zFirst) + 1;
+ va_start(ap, zFirst);
+ while( (z = va_arg(ap, const char*))!=0 ){
+ nByte += strlen(z);
+ }
+ va_end(ap);
+ sqliteFree(*pz);
+ *pz = zResult = sqliteMallocRaw( nByte );
+ if( zResult==0 ){
+ return;
+ }
+ strcpy(zResult, zFirst);
+ zResult += strlen(zResult);
+ va_start(ap, zFirst);
+ while( (z = va_arg(ap, const char*))!=0 ){
+ strcpy(zResult, z);
+ zResult += strlen(zResult);
+ }
+ va_end(ap);
+#ifdef MEMORY_DEBUG
+#if MEMORY_DEBUG>1
+ fprintf(stderr,"string at 0x%x is %s\n", (int)*pz, *pz);
+#endif
+#endif
+}
+
+/*
+** Works like sqliteSetString, but each string is now followed by
+** a length integer which specifies how much of the source string
+** to copy (in bytes). -1 means use the whole string. The 1st
+** argument must either be NULL or point to memory obtained from
+** sqliteMalloc().
+*/
+void sqliteSetNString(char **pz, ...){
+ va_list ap;
+ int nByte;
+ const char *z;
+ char *zResult;
+ int n;
+
+ if( pz==0 ) return;
+ nByte = 0;
+ va_start(ap, pz);
+ while( (z = va_arg(ap, const char*))!=0 ){
+ n = va_arg(ap, int);
+ if( n<=0 ) n = strlen(z);
+ nByte += n;
+ }
+ va_end(ap);
+ sqliteFree(*pz);
+ *pz = zResult = sqliteMallocRaw( nByte + 1 );
+ if( zResult==0 ) return;
+ va_start(ap, pz);
+ while( (z = va_arg(ap, const char*))!=0 ){
+ n = va_arg(ap, int);
+ if( n<=0 ) n = strlen(z);
+ strncpy(zResult, z, n);
+ zResult += n;
+ }
+ *zResult = 0;
+#ifdef MEMORY_DEBUG
+#if MEMORY_DEBUG>1
+ fprintf(stderr,"string at 0x%x is %s\n", (int)*pz, *pz);
+#endif
+#endif
+ va_end(ap);
+}
+
+/*
+** Add an error message to pParse->zErrMsg and increment pParse->nErr.
+** The following formatting characters are allowed:
+**
+** %s Insert a string
+** %z A string that should be freed after use
+** %d Insert an integer
+** %T Insert a token
+** %S Insert the first element of a SrcList
+*/
+void sqliteErrorMsg(Parse *pParse, const char *zFormat, ...){
+ va_list ap;
+ pParse->nErr++;
+ sqliteFree(pParse->zErrMsg);
+ va_start(ap, zFormat);
+ pParse->zErrMsg = sqliteVMPrintf(zFormat, ap);
+ va_end(ap);
+}
+
+/*
+** 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.
+**
+** 2002-Feb-14: This routine is extended to remove MS-Access style
+** brackets from around identifers. For example: "[a-b-c]" becomes
+** "a-b-c".
+*/
+void sqliteDequote(char *z){
+ int quote;
+ int i, j;
+ if( z==0 ) return;
+ quote = z[0];
+ switch( quote ){
+ case '\'': break;
+ case '"': break;
+ case '[': quote = ']'; break;
+ default: return;
+ }
+ for(i=1, j=0; z[i]; i++){
+ if( z[i]==quote ){
+ if( z[i+1]==quote ){
+ z[j++] = quote;
+ i++;
+ }else{
+ z[j++] = 0;
+ break;
+ }
+ }else{
+ z[j++] = z[i];
+ }
+ }
+}
+
+/* An array to map all upper-case characters into their corresponding
+** lower-case character.
+*/
+static unsigned char UpperToLower[] = {
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
+ 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
+ 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,
+ 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 97, 98, 99,100,101,102,103,
+ 104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,
+ 122, 91, 92, 93, 94, 95, 96, 97, 98, 99,100,101,102,103,104,105,106,107,
+ 108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,
+ 126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,
+ 144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,
+ 162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,
+ 180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,
+ 198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,
+ 216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,
+ 234,235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,
+ 252,253,254,255
+};
+
+/*
+** This function computes a hash on the name of a keyword.
+** Case is not significant.
+*/
+int sqliteHashNoCase(const char *z, int n){
+ int h = 0;
+ if( n<=0 ) n = strlen(z);
+ while( n > 0 ){
+ h = (h<<3) ^ h ^ UpperToLower[(unsigned char)*z++];
+ n--;
+ }
+ return h & 0x7fffffff;
+}
+
+/*
+** Some systems have stricmp(). Others have strcasecmp(). Because
+** there is no consistency, we will define our own.
+*/
+int sqliteStrICmp(const char *zLeft, const char *zRight){
+ register unsigned char *a, *b;
+ a = (unsigned char *)zLeft;
+ b = (unsigned char *)zRight;
+ while( *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
+ return *a - *b;
+}
+int sqliteStrNICmp(const char *zLeft, const char *zRight, int N){
+ register unsigned char *a, *b;
+ a = (unsigned char *)zLeft;
+ b = (unsigned char *)zRight;
+ while( N-- > 0 && *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
+ return N<0 ? 0 : *a - *b;
+}
+
+/*
+** Return TRUE if z is a pure numeric string. Return FALSE if the
+** string contains any character which is not part of a number.
+**
+** Am empty string is considered non-numeric.
+*/
+int sqliteIsNumber(const char *z){
+ if( *z=='-' || *z=='+' ) z++;
+ if( !isdigit(*z) ){
+ return 0;
+ }
+ z++;
+ while( isdigit(*z) ){ z++; }
+ if( *z=='.' ){
+ z++;
+ if( !isdigit(*z) ) return 0;
+ while( isdigit(*z) ){ z++; }
+ }
+ if( *z=='e' || *z=='E' ){
+ z++;
+ if( *z=='+' || *z=='-' ) z++;
+ if( !isdigit(*z) ) return 0;
+ while( isdigit(*z) ){ z++; }
+ }
+ return *z==0;
+}
+
+/*
+** The string z[] is an ascii representation of a real number.
+** Convert this string to a double.
+**
+** This routine assumes that z[] really is a valid number. If it
+** is not, the result is undefined.
+**
+** This routine is used instead of the library atof() function because
+** the library atof() might want to use "," as the decimal point instead
+** of "." depending on how locale is set. But that would cause problems
+** for SQL. So this routine always uses "." regardless of locale.
+*/
+double sqliteAtoF(const char *z, const char **pzEnd){
+ int sign = 1;
+ LONGDOUBLE_TYPE v1 = 0.0;
+ if( *z=='-' ){
+ sign = -1;
+ z++;
+ }else if( *z=='+' ){
+ z++;
+ }
+ while( isdigit(*z) ){
+ v1 = v1*10.0 + (*z - '0');
+ z++;
+ }
+ if( *z=='.' ){
+ LONGDOUBLE_TYPE divisor = 1.0;
+ z++;
+ while( isdigit(*z) ){
+ v1 = v1*10.0 + (*z - '0');
+ divisor *= 10.0;
+ z++;
+ }
+ v1 /= divisor;
+ }
+ if( *z=='e' || *z=='E' ){
+ int esign = 1;
+ int eval = 0;
+ LONGDOUBLE_TYPE scale = 1.0;
+ z++;
+ if( *z=='-' ){
+ esign = -1;
+ z++;
+ }else if( *z=='+' ){
+ z++;
+ }
+ while( isdigit(*z) ){
+ eval = eval*10 + *z - '0';
+ z++;
+ }
+ while( eval>=64 ){ scale *= 1.0e+64; eval -= 64; }
+ while( eval>=16 ){ scale *= 1.0e+16; eval -= 16; }
+ while( eval>=4 ){ scale *= 1.0e+4; eval -= 4; }
+ while( eval>=1 ){ scale *= 1.0e+1; eval -= 1; }
+ if( esign<0 ){
+ v1 /= scale;
+ }else{
+ v1 *= scale;
+ }
+ }
+ if( pzEnd ) *pzEnd = z;
+ return sign<0 ? -v1 : v1;
+}
+
+/*
+** The string zNum represents an integer. There might be some other
+** information following the integer too, but that part is ignored.
+** If the integer that the prefix of zNum represents will fit in a
+** 32-bit signed integer, return TRUE. Otherwise return FALSE.
+**
+** This routine returns FALSE for the string -2147483648 even that
+** that number will, in theory fit in a 32-bit integer. But positive
+** 2147483648 will not fit in 32 bits. So it seems safer to return
+** false.
+*/
+int sqliteFitsIn32Bits(const char *zNum){
+ int i, c;
+ if( *zNum=='-' || *zNum=='+' ) zNum++;
+ for(i=0; (c=zNum[i])>='0' && c<='9'; i++){}
+ return i<10 || (i==10 && memcmp(zNum,"2147483647",10)<=0);
+}
+
+/* This comparison routine is what we use for comparison operations
+** between numeric values in an SQL expression. "Numeric" is a little
+** bit misleading here. What we mean is that the strings have a
+** type of "numeric" from the point of view of SQL. The strings
+** do not necessarily contain numbers. They could contain text.
+**
+** If the input strings both look like actual numbers then they
+** compare in numerical order. Numerical strings are always less
+** than non-numeric strings so if one input string looks like a
+** number and the other does not, then the one that looks like
+** a number is the smaller. Non-numeric strings compare in
+** lexigraphical order (the same order as strcmp()).
+*/
+int sqliteCompare(const char *atext, const char *btext){
+ int result;
+ int isNumA, isNumB;
+ if( atext==0 ){
+ return -1;
+ }else if( btext==0 ){
+ return 1;
+ }
+ isNumA = sqliteIsNumber(atext);
+ isNumB = sqliteIsNumber(btext);
+ if( isNumA ){
+ if( !isNumB ){
+ result = -1;
+ }else{
+ double rA, rB;
+ rA = sqliteAtoF(atext, 0);
+ rB = sqliteAtoF(btext, 0);
+ if( rA<rB ){
+ result = -1;
+ }else if( rA>rB ){
+ result = +1;
+ }else{
+ result = 0;
+ }
+ }
+ }else if( isNumB ){
+ result = +1;
+ }else {
+ result = strcmp(atext, btext);
+ }
+ return result;
+}
+
+/*
+** This routine is used for sorting. Each key is a list of one or more
+** null-terminated elements. The list is terminated by two nulls in
+** a row. For example, the following text is a key with three elements
+**
+** Aone\000Dtwo\000Athree\000\000
+**
+** All elements begin with one of the characters "+-AD" and end with "\000"
+** with zero or more text elements in between. Except, NULL elements
+** consist of the special two-character sequence "N\000".
+**
+** Both arguments will have the same number of elements. This routine
+** returns negative, zero, or positive if the first argument is less
+** than, equal to, or greater than the first. (Result is a-b).
+**
+** Each element begins with one of the characters "+", "-", "A", "D".
+** This character determines the sort order and collating sequence:
+**
+** + Sort numerically in ascending order
+** - Sort numerically in descending order
+** A Sort as strings in ascending order
+** D Sort as strings in descending order.
+**
+** For the "+" and "-" sorting, pure numeric strings (strings for which the
+** isNum() function above returns TRUE) always compare less than strings
+** that are not pure numerics. Non-numeric strings compare in memcmp()
+** order. This is the same sort order as the sqliteCompare() function
+** above generates.
+**
+** The last point is a change from version 2.6.3 to version 2.7.0. In
+** version 2.6.3 and earlier, substrings of digits compare in numerical
+** and case was used only to break a tie.
+**
+** Elements that begin with 'A' or 'D' compare in memcmp() order regardless
+** of whether or not they look like a number.
+**
+** Note that the sort order imposed by the rules above is the same
+** from the ordering defined by the "<", "<=", ">", and ">=" operators
+** of expressions and for indices. This was not the case for version
+** 2.6.3 and earlier.
+*/
+int sqliteSortCompare(const char *a, const char *b){
+ int res = 0;
+ int isNumA, isNumB;
+ int dir = 0;
+
+ while( res==0 && *a && *b ){
+ if( a[0]=='N' || b[0]=='N' ){
+ if( a[0]==b[0] ){
+ a += 2;
+ b += 2;
+ continue;
+ }
+ if( a[0]=='N' ){
+ dir = b[0];
+ res = -1;
+ }else{
+ dir = a[0];
+ res = +1;
+ }
+ break;
+ }
+ assert( a[0]==b[0] );
+ if( (dir=a[0])=='A' || a[0]=='D' ){
+ res = strcmp(&a[1],&b[1]);
+ if( res ) break;
+ }else{
+ isNumA = sqliteIsNumber(&a[1]);
+ isNumB = sqliteIsNumber(&b[1]);
+ if( isNumA ){
+ double rA, rB;
+ if( !isNumB ){
+ res = -1;
+ break;
+ }
+ rA = sqliteAtoF(&a[1], 0);
+ rB = sqliteAtoF(&b[1], 0);
+ if( rA<rB ){
+ res = -1;
+ break;
+ }
+ if( rA>rB ){
+ res = +1;
+ break;
+ }
+ }else if( isNumB ){
+ res = +1;
+ break;
+ }else{
+ res = strcmp(&a[1],&b[1]);
+ if( res ) break;
+ }
+ }
+ a += strlen(&a[1]) + 2;
+ b += strlen(&b[1]) + 2;
+ }
+ if( dir=='-' || dir=='D' ) res = -res;
+ return res;
+}
+
+/*
+** Some powers of 64. These constants are needed in the
+** sqliteRealToSortable() routine below.
+*/
+#define _64e3 (64.0 * 64.0 * 64.0)
+#define _64e4 (64.0 * 64.0 * 64.0 * 64.0)
+#define _64e15 (_64e3 * _64e4 * _64e4 * _64e4)
+#define _64e16 (_64e4 * _64e4 * _64e4 * _64e4)
+#define _64e63 (_64e15 * _64e16 * _64e16 * _64e16)
+#define _64e64 (_64e16 * _64e16 * _64e16 * _64e16)
+
+/*
+** The following procedure converts a double-precision floating point
+** number into a string. The resulting string has the property that
+** two such strings comparied using strcmp() or memcmp() will give the
+** same results as a numeric comparison of the original floating point
+** numbers.
+**
+** This routine is used to generate database keys from floating point
+** numbers such that the keys sort in the same order as the original
+** floating point numbers even though the keys are compared using
+** memcmp().
+**
+** The calling function should have allocated at least 14 characters
+** of space for the buffer z[].
+*/
+void sqliteRealToSortable(double r, char *z){
+ int neg;
+ int exp;
+ int cnt = 0;
+
+ /* This array maps integers between 0 and 63 into base-64 digits.
+ ** The digits must be chosen such at their ASCII codes are increasing.
+ ** This means we can not use the traditional base-64 digit set. */
+ static const char zDigit[] =
+ "0123456789"
+ "ABCDEFGHIJKLMNOPTQRSTUVWXYZ"
+ "abcdefghijklmnopqrstuvwxyz"
+ "|~";
+ if( r<0.0 ){
+ neg = 1;
+ r = -r;
+ *z++ = '-';
+ } else {
+ neg = 0;
+ *z++ = '0';
+ }
+ exp = 0;
+
+ if( r==0.0 ){
+ exp = -1024;
+ }else if( r<(0.5/64.0) ){
+ while( r < 0.5/_64e64 && exp > -961 ){ r *= _64e64; exp -= 64; }
+ while( r < 0.5/_64e16 && exp > -1009 ){ r *= _64e16; exp -= 16; }
+ while( r < 0.5/_64e4 && exp > -1021 ){ r *= _64e4; exp -= 4; }
+ while( r < 0.5/64.0 && exp > -1024 ){ r *= 64.0; exp -= 1; }
+ }else if( r>=0.5 ){
+ while( r >= 0.5*_64e63 && exp < 960 ){ r *= 1.0/_64e64; exp += 64; }
+ while( r >= 0.5*_64e15 && exp < 1008 ){ r *= 1.0/_64e16; exp += 16; }
+ while( r >= 0.5*_64e3 && exp < 1020 ){ r *= 1.0/_64e4; exp += 4; }
+ while( r >= 0.5 && exp < 1023 ){ r *= 1.0/64.0; exp += 1; }
+ }
+ if( neg ){
+ exp = -exp;
+ r = -r;
+ }
+ exp += 1024;
+ r += 0.5;
+ if( exp<0 ) return;
+ if( exp>=2048 || r>=1.0 ){
+ strcpy(z, "~~~~~~~~~~~~");
+ return;
+ }
+ *z++ = zDigit[(exp>>6)&0x3f];
+ *z++ = zDigit[exp & 0x3f];
+ while( r>0.0 && cnt<10 ){
+ int digit;
+ r *= 64.0;
+ digit = (int)r;
+ assert( digit>=0 && digit<64 );
+ *z++ = zDigit[digit & 0x3f];
+ r -= digit;
+ cnt++;
+ }
+ *z = 0;
+}
+
+#ifdef SQLITE_UTF8
+/*
+** X is a pointer to the first byte of a UTF-8 character. Increment
+** X so that it points to the next character. This only works right
+** if X points to a well-formed UTF-8 string.
+*/
+#define sqliteNextChar(X) while( (0xc0&*++(X))==0x80 ){}
+#define sqliteCharVal(X) sqlite_utf8_to_int(X)
+
+#else /* !defined(SQLITE_UTF8) */
+/*
+** For iso8859 encoding, the next character is just the next byte.
+*/
+#define sqliteNextChar(X) (++(X));
+#define sqliteCharVal(X) ((int)*(X))
+
+#endif /* defined(SQLITE_UTF8) */
+
+
+#ifdef SQLITE_UTF8
+/*
+** Convert the UTF-8 character to which z points into a 31-bit
+** UCS character. This only works right if z points to a well-formed
+** UTF-8 string.
+*/
+static int sqlite_utf8_to_int(const unsigned char *z){
+ int c;
+ static const int initVal[] = {
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
+ 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
+ 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44,
+ 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,
+ 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,
+ 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,
+ 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,
+ 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,
+ 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,
+ 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149,
+ 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164,
+ 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179,
+ 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 0, 1, 2,
+ 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
+ 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 0,
+ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 0, 1, 254,
+ 255,
+ };
+ c = initVal[*(z++)];
+ while( (0xc0&*z)==0x80 ){
+ c = (c<<6) | (0x3f&*(z++));
+ }
+ return c;
+}
+#endif
+
+/*
+** Compare two UTF-8 strings for equality where the first string can
+** potentially be a "glob" expression. Return true (1) if they
+** are the same and false (0) if they are different.
+**
+** Globbing rules:
+**
+** '*' Matches any sequence of zero or more characters.
+**
+** '?' Matches exactly one character.
+**
+** [...] Matches one character from the enclosed list of
+** characters.
+**
+** [^...] Matches one character not in the enclosed list.
+**
+** With the [...] and [^...] matching, a ']' character can be included
+** in the list by making it the first character after '[' or '^'. A
+** range of characters can be specified using '-'. Example:
+** "[a-z]" matches any single lower-case letter. To match a '-', make
+** it the last character in the list.
+**
+** This routine is usually tquick, but can be N**2 in the worst case.
+**
+** Hints: to match '*' or '?', put them in "[]". Like this:
+**
+** abc[*]xyz Matches "abc*xyz" only
+*/
+int
+sqliteGlobCompare(const unsigned char *zPattern, const unsigned char *zString){
+ register int c;
+ int invert;
+ int seen;
+ int c2;
+
+ while( (c = *zPattern)!=0 ){
+ switch( c ){
+ case '*':
+ while( (c=zPattern[1]) == '*' || c == '?' ){
+ if( c=='?' ){
+ if( *zString==0 ) return 0;
+ sqliteNextChar(zString);
+ }
+ zPattern++;
+ }
+ if( c==0 ) return 1;
+ if( c=='[' ){
+ while( *zString && sqliteGlobCompare(&zPattern[1],zString)==0 ){
+ sqliteNextChar(zString);
+ }
+ return *zString!=0;
+ }else{
+ while( (c2 = *zString)!=0 ){
+ while( c2 != 0 && c2 != c ){ c2 = *++zString; }
+ if( c2==0 ) return 0;
+ if( sqliteGlobCompare(&zPattern[1],zString) ) return 1;
+ sqliteNextChar(zString);
+ }
+ return 0;
+ }
+ case '?': {
+ if( *zString==0 ) return 0;
+ sqliteNextChar(zString);
+ zPattern++;
+ break;
+ }
+ case '[': {
+ int prior_c = 0;
+ seen = 0;
+ invert = 0;
+ c = sqliteCharVal(zString);
+ if( c==0 ) return 0;
+ c2 = *++zPattern;
+ if( c2=='^' ){ invert = 1; c2 = *++zPattern; }
+ if( c2==']' ){
+ if( c==']' ) seen = 1;
+ c2 = *++zPattern;
+ }
+ while( (c2 = sqliteCharVal(zPattern))!=0 && c2!=']' ){
+ if( c2=='-' && zPattern[1]!=']' && zPattern[1]!=0 && prior_c>0 ){
+ zPattern++;
+ c2 = sqliteCharVal(zPattern);
+ if( c>=prior_c && c<=c2 ) seen = 1;
+ prior_c = 0;
+ }else if( c==c2 ){
+ seen = 1;
+ prior_c = c2;
+ }else{
+ prior_c = c2;
+ }
+ sqliteNextChar(zPattern);
+ }
+ if( c2==0 || (seen ^ invert)==0 ) return 0;
+ sqliteNextChar(zString);
+ zPattern++;
+ break;
+ }
+ default: {
+ if( c != *zString ) return 0;
+ zPattern++;
+ zString++;
+ break;
+ }
+ }
+ }
+ return *zString==0;
+}
+
+/*
+** Compare two UTF-8 strings for equality using the "LIKE" operator of
+** SQL. The '%' character matches any sequence of 0 or more
+** characters and '_' matches any single character. Case is
+** not significant.
+**
+** This routine is just an adaptation of the sqliteGlobCompare()
+** routine above.
+*/
+int
+sqliteLikeCompare(const unsigned char *zPattern, const unsigned char *zString){
+ register int c;
+ int c2;
+
+ while( (c = UpperToLower[*zPattern])!=0 ){
+ switch( c ){
+ case '%': {
+ while( (c=zPattern[1]) == '%' || c == '_' ){
+ if( c=='_' ){
+ if( *zString==0 ) return 0;
+ sqliteNextChar(zString);
+ }
+ zPattern++;
+ }
+ if( c==0 ) return 1;
+ c = UpperToLower[c];
+ while( (c2=UpperToLower[*zString])!=0 ){
+ while( c2 != 0 && c2 != c ){ c2 = UpperToLower[*++zString]; }
+ if( c2==0 ) return 0;
+ if( sqliteLikeCompare(&zPattern[1],zString) ) return 1;
+ sqliteNextChar(zString);
+ }
+ return 0;
+ }
+ case '_': {
+ if( *zString==0 ) return 0;
+ sqliteNextChar(zString);
+ zPattern++;
+ break;
+ }
+ default: {
+ if( c != UpperToLower[*zString] ) return 0;
+ zPattern++;
+ zString++;
+ break;
+ }
+ }
+ }
+ return *zString==0;
+}
+
+/*
+** Change the sqlite.magic from SQLITE_MAGIC_OPEN to SQLITE_MAGIC_BUSY.
+** Return an error (non-zero) if the magic was not SQLITE_MAGIC_OPEN
+** when this routine is called.
+**
+** This routine is a attempt to detect if two threads use the
+** same sqlite* pointer at the same time. There is a race
+** condition so it is possible that the error is not detected.
+** But usually the problem will be seen. The result will be an
+** error which can be used to debug the application that is
+** using SQLite incorrectly.
+**
+** Ticket #202: If db->magic is not a valid open value, take care not
+** to modify the db structure at all. It could be that db is a stale
+** pointer. In other words, it could be that there has been a prior
+** call to sqlite_close(db) and db has been deallocated. And we do
+** not want to write into deallocated memory.
+*/
+int sqliteSafetyOn(sqlite *db){
+ if( db->magic==SQLITE_MAGIC_OPEN ){
+ db->magic = SQLITE_MAGIC_BUSY;
+ return 0;
+ }else if( db->magic==SQLITE_MAGIC_BUSY || db->magic==SQLITE_MAGIC_ERROR
+ || db->want_to_close ){
+ db->magic = SQLITE_MAGIC_ERROR;
+ db->flags |= SQLITE_Interrupt;
+ }
+ return 1;
+}
+
+/*
+** Change the magic from SQLITE_MAGIC_BUSY to SQLITE_MAGIC_OPEN.
+** Return an error (non-zero) if the magic was not SQLITE_MAGIC_BUSY
+** when this routine is called.
+*/
+int sqliteSafetyOff(sqlite *db){
+ if( db->magic==SQLITE_MAGIC_BUSY ){
+ db->magic = SQLITE_MAGIC_OPEN;
+ return 0;
+ }else if( db->magic==SQLITE_MAGIC_OPEN || db->magic==SQLITE_MAGIC_ERROR
+ || db->want_to_close ){
+ db->magic = SQLITE_MAGIC_ERROR;
+ db->flags |= SQLITE_Interrupt;
+ }
+ return 1;
+}
+
+/*
+** Check to make sure we are not currently executing an sqlite_exec().
+** If we are currently in an sqlite_exec(), return true and set
+** sqlite.magic to SQLITE_MAGIC_ERROR. This will cause a complete
+** shutdown of the database.
+**
+** This routine is used to try to detect when API routines are called
+** at the wrong time or in the wrong sequence.
+*/
+int sqliteSafetyCheck(sqlite *db){
+ if( db->pVdbe!=0 ){
+ db->magic = SQLITE_MAGIC_ERROR;
+ return 1;
+ }
+ return 0;
+}