sqlite/src/func.c at master · codegear/sqlite

2945 lines (2826 loc) · 89 KB
** 2002 February 23
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
*************************************************************************
** This file contains the C-language implementations for many of the SQL
** functions of SQLite.  (Some function, and in particular the date and
** time functions, are implemented separately.)
#include "sqliteInt.h"
#include <stdlib.h>
#include <assert.h>
#ifndef SQLITE_OMIT_FLOATING_POINT
#include <math.h>
#include "vdbeInt.h"
** Return the collating function associated with a function.
static CollSeq *sqlite3GetFuncCollSeq(sqlite3_context *context){
  VdbeOp *pOp;
  assert( context->pVdbe!=0 );
  pOp = &context->pVdbe->aOp[context->iOp-1];
  assert( pOp->opcode==OP_CollSeq );
  assert( pOp->p4type==P4_COLLSEQ );
  return pOp->p4.pColl;
** Indicate that the accumulator load should be skipped on this
** iteration of the aggregate loop.
static void sqlite3SkipAccumulatorLoad(sqlite3_context *context){
  assert( context->isError<=0 );
  context->isError = -1;
  context->skipFlag = 1;
** Implementation of the non-aggregate min() and max() functions
static void minmaxFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
  int mask;    /* 0 for min() or 0xffffffff for max() */
  int iBest;
  CollSeq *pColl;
  assert( argc>1 );
  mask = sqlite3_user_data(context)==0 ? 0 : -1;
  pColl = sqlite3GetFuncCollSeq(context);
  assert( pColl );
  assert( mask==-1 || mask==0 );
  iBest = 0;
  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
  for(i=1; i<argc; i++){
    if( sqlite3_value_type(argv[i])==SQLITE_NULL ) return;
    if( (sqlite3MemCompare(argv[iBest], argv[i], pColl)^mask)>=0 ){
      testcase( mask==0 );
      iBest = i;
  sqlite3_result_value(context, argv[iBest]);
** Return the type of the argument.
static void typeofFunc(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **argv
  static const char *azType[] = { "integer", "real", "text", "blob", "null" };
  int i = sqlite3_value_type(argv[0]) - 1;
  UNUSED_PARAMETER(NotUsed);
  assert( i>=0 && i<ArraySize(azType) );
  assert( SQLITE_INTEGER==1 );
  assert( SQLITE_FLOAT==2 );
  assert( SQLITE_TEXT==3 );
  assert( SQLITE_BLOB==4 );
  assert( SQLITE_NULL==5 );
  /* EVIDENCE-OF: R-01470-60482 The sqlite3_value_type(V) interface returns
  ** the datatype code for the initial datatype of the sqlite3_value object
  ** V. The returned value is one of SQLITE_INTEGER, SQLITE_FLOAT,
  ** SQLITE_TEXT, SQLITE_BLOB, or SQLITE_NULL. */
  sqlite3_result_text(context, azType[i], -1, SQLITE_STATIC);
/* subtype(X)
** Return the subtype of X
static void subtypeFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
  UNUSED_PARAMETER(argc);
  sqlite3_result_int(context, sqlite3_value_subtype(argv[0]));
** Implementation of the length() function
static void lengthFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
  assert( argc==1 );
  UNUSED_PARAMETER(argc);
  switch( sqlite3_value_type(argv[0]) ){
    case SQLITE_BLOB:
    case SQLITE_INTEGER:
    case SQLITE_FLOAT: {
      sqlite3_result_int(context, sqlite3_value_bytes(argv[0]));
      break;
    case SQLITE_TEXT: {
      const unsigned char *z = sqlite3_value_text(argv[0]);
      const unsigned char *z0;
      unsigned char c;
      if( z==0 ) return;
      z0 = z;
      while( (c = *z)!=0 ){
        z++;
        if( c>=0xc0 ){
          while( (*z & 0xc0)==0x80 ){ z++; z0++; }
      sqlite3_result_int(context, (int)(z-z0));
      break;
    default: {
      sqlite3_result_null(context);
      break;
** Implementation of the octet_length() function
static void bytelengthFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
  assert( argc==1 );
  UNUSED_PARAMETER(argc);
  switch( sqlite3_value_type(argv[0]) ){
    case SQLITE_BLOB: {
      sqlite3_result_int(context, sqlite3_value_bytes(argv[0]));
      break;
    case SQLITE_INTEGER:
    case SQLITE_FLOAT: {
      i64 m = sqlite3_context_db_handle(context)->enc<=SQLITE_UTF8 ? 1 : 2;
      sqlite3_result_int64(context, sqlite3_value_bytes(argv[0])*m);
      break;
    case SQLITE_TEXT: {
      if( sqlite3_value_encoding(argv[0])<=SQLITE_UTF8 ){
        sqlite3_result_int(context, sqlite3_value_bytes(argv[0]));
      }else{
        sqlite3_result_int(context, sqlite3_value_bytes16(argv[0]));
      break;
    default: {
      sqlite3_result_null(context);
      break;
** Implementation of the abs() function.
** IMP: R-23979-26855 The abs(X) function returns the absolute value of
** the numeric argument X.
static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
  assert( argc==1 );
  UNUSED_PARAMETER(argc);
  switch( sqlite3_value_type(argv[0]) ){
    case SQLITE_INTEGER: {
      i64 iVal = sqlite3_value_int64(argv[0]);
      if( iVal<0 ){
        if( iVal==SMALLEST_INT64 ){
          /* IMP: R-31676-45509 If X is the integer -9223372036854775808
          ** then abs(X) throws an integer overflow error since there is no
          ** equivalent positive 64-bit two complement value. */
          sqlite3_result_error(context, "integer overflow", -1);
          return;
        iVal = -iVal;
      sqlite3_result_int64(context, iVal);
      break;
    case SQLITE_NULL: {
      /* IMP: R-37434-19929 Abs(X) returns NULL if X is NULL. */
      sqlite3_result_null(context);
      break;
    default: {
      /* Because sqlite3_value_double() returns 0.0 if the argument is not
      ** something that can be converted into a number, we have:
      ** IMP: R-01992-00519 Abs(X) returns 0.0 if X is a string or blob
      ** that cannot be converted to a numeric value.
      double rVal = sqlite3_value_double(argv[0]);
      if( rVal<0 ) rVal = -rVal;
      sqlite3_result_double(context, rVal);
      break;
** Implementation of the instr() function.
** instr(haystack,needle) finds the first occurrence of needle
** in haystack and returns the number of previous characters plus 1,
** or 0 if needle does not occur within haystack.
** If both haystack and needle are BLOBs, then the result is one more than
** the number of bytes in haystack prior to the first occurrence of needle,
** or 0 if needle never occurs in haystack.
static void instrFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
  const unsigned char *zHaystack;
  const unsigned char *zNeedle;
  int nHaystack;
  int nNeedle;
  int typeHaystack, typeNeedle;
  int N = 1;
  int isText;
  unsigned char firstChar;
  sqlite3_value *pC1 = 0;
  sqlite3_value *pC2 = 0;
  UNUSED_PARAMETER(argc);
  typeHaystack = sqlite3_value_type(argv[0]);
  typeNeedle = sqlite3_value_type(argv[1]);
  if( typeHaystack==SQLITE_NULL || typeNeedle==SQLITE_NULL ) return;
  nHaystack = sqlite3_value_bytes(argv[0]);
  nNeedle = sqlite3_value_bytes(argv[1]);
  if( nNeedle>0 ){
    if( typeHaystack==SQLITE_BLOB && typeNeedle==SQLITE_BLOB ){
      zHaystack = sqlite3_value_blob(argv[0]);
      zNeedle = sqlite3_value_blob(argv[1]);
      isText = 0;
    }else if( typeHaystack!=SQLITE_BLOB && typeNeedle!=SQLITE_BLOB ){
      zHaystack = sqlite3_value_text(argv[0]);
      zNeedle = sqlite3_value_text(argv[1]);
      isText = 1;
      pC1 = sqlite3_value_dup(argv[0]);
      zHaystack = sqlite3_value_text(pC1);
      if( zHaystack==0 ) goto endInstrOOM;
      nHaystack = sqlite3_value_bytes(pC1);
      pC2 = sqlite3_value_dup(argv[1]);
      zNeedle = sqlite3_value_text(pC2);
      if( zNeedle==0 ) goto endInstrOOM;
      nNeedle = sqlite3_value_bytes(pC2);
      isText = 1;
    if( zNeedle==0 || (nHaystack && zHaystack==0) ) goto endInstrOOM;
    firstChar = zNeedle[0];
    while( nNeedle<=nHaystack
       && (zHaystack[0]!=firstChar || memcmp(zHaystack, zNeedle, nNeedle)!=0)
        nHaystack--;
        zHaystack++;
      }while( isText && (zHaystack[0]&0xc0)==0x80 );
    if( nNeedle>nHaystack ) N = 0;
  sqlite3_result_int(context, N);
  sqlite3_value_free(pC1);
  sqlite3_value_free(pC2);
endInstrOOM:
  sqlite3_result_error_nomem(context);
  goto endInstr;
** Implementation of the printf() (a.k.a. format()) SQL function.
static void printfFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
  PrintfArguments x;
  StrAccum str;
  const char *zFormat;
  sqlite3 *db = sqlite3_context_db_handle(context);
  if( argc>=1 && (zFormat = (const char*)sqlite3_value_text(argv[0]))!=0 ){
    x.nArg = argc-1;
    x.nUsed = 0;
    x.apArg = argv+1;
    sqlite3StrAccumInit(&str, db, 0, 0, db->aLimit[SQLITE_LIMIT_LENGTH]);
    str.printfFlags = SQLITE_PRINTF_SQLFUNC;
    sqlite3_str_appendf(&str, zFormat, &x);
    n = str.nChar;
    sqlite3_result_text(context, sqlite3StrAccumFinish(&str), n,
                        SQLITE_DYNAMIC);
** Implementation of the substr() function.
** substr(x,p1,p2)  returns p2 characters of x[] beginning with p1.
** p1 is 1-indexed.  So substr(x,1,1) returns the first character
** of x.  If x is text, then we actually count UTF-8 characters.
** If x is a blob, then we count bytes.
** If p1 is negative, then we begin abs(p1) from the end of x[].
** If p2 is negative, return the p2 characters preceding p1.
static void substrFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
  const unsigned char *z;
  const unsigned char *z2;
  int p0type;
  i64 p1, p2;
  assert( argc==3 || argc==2 );
  p0type = sqlite3_value_type(argv[0]);
  p1 = sqlite3_value_int64(argv[1]);
  if( p0type==SQLITE_BLOB ){
    len = sqlite3_value_bytes(argv[0]);
    z = sqlite3_value_blob(argv[0]);
    if( z==0 ) return;
    assert( len==sqlite3_value_bytes(argv[0]) );
    z = sqlite3_value_text(argv[0]);
    if( z==0 ) return;
    len = 0;
    if( p1<0 ){
      for(z2=z; *z2; len++){
        SQLITE_SKIP_UTF8(z2);
  if( argc==3 ){
    p2 = sqlite3_value_int64(argv[2]);
    if( p2==0 && sqlite3_value_type(argv[2])==SQLITE_NULL ) return;
    p2 = sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH];
  if( p1==0 ){
#ifdef SQLITE_SUBSTR_COMPATIBILITY
    /* If SUBSTR_COMPATIBILITY is defined then substr(X,0,N) work the same as
    ** as substr(X,1,N) - it returns the first N characters of X.  This
    ** is essentially a back-out of the bug-fix in check-in [5fc125d362df4b8]
    ** from 2009-02-02 for compatibility of applications that exploited the
    ** old buggy behavior. */
    p1 = 1; /* <rdar://problem/6778339> */
    if( sqlite3_value_type(argv[1])==SQLITE_NULL ) return;
  if( p1<0 ){
    p1 += len;
    if( p1<0 ){
      if( p2<0 ){
      }else{
        p2 += p1;
      p1 = 0;
  }else if( p1>0 ){
  }else if( p2>0 ){
  if( p2<0 ){
    if( p2<-p1 ){
      p2 = p1;
      p2 = -p2;
    p1 -= p2;
  assert( p1>=0 && p2>=0 );
  if( p0type!=SQLITE_BLOB ){
    while( *z && p1 ){
      SQLITE_SKIP_UTF8(z);
      p1--;
    for(z2=z; *z2 && p2; p2--){
      SQLITE_SKIP_UTF8(z2);
    sqlite3_result_text64(context, (char*)z, z2-z, SQLITE_TRANSIENT,
                          SQLITE_UTF8);
    if( p1>=len ){
      p1 = p2 = 0;
    }else if( p2>len-p1 ){
      p2 = len-p1;
      assert( p2>0 );
    sqlite3_result_blob64(context, (char*)&z[p1], (u64)p2, SQLITE_TRANSIENT);
** Implementation of the round() function
#ifndef SQLITE_OMIT_FLOATING_POINT
static void roundFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
  i64 n = 0;
  double r;
  char *zBuf;
  assert( argc==1 || argc==2 );
  if( argc==2 ){
    if( SQLITE_NULL==sqlite3_value_type(argv[1]) ) return;
    n = sqlite3_value_int64(argv[1]);
    if( n>30 ) n = 30;
    if( n<0 ) n = 0;
  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
  r = sqlite3_value_double(argv[0]);
  /* If Y==0 and X will fit in a 64-bit int,
  ** handle the rounding directly,
  ** otherwise use printf.
  if( r<-4503599627370496.0 || r>+4503599627370496.0 ){
    /* The value has no fractional part so there is nothing to round */
  }else if( n==0 ){ 
    r = (double)((sqlite_int64)(r+(r<0?-0.5:+0.5)));
    zBuf = sqlite3_mprintf("%!.*f",(int)n,r);
    if( zBuf==0 ){
      sqlite3_result_error_nomem(context);
      return;
    sqlite3AtoF(zBuf, &r, sqlite3Strlen30(zBuf), SQLITE_UTF8);
    sqlite3_free(zBuf);
  sqlite3_result_double(context, r);
** Allocate nByte bytes of space using sqlite3Malloc(). If the
** allocation fails, call sqlite3_result_error_nomem() to notify
** the database handle that malloc() has failed and return NULL.
** If nByte is larger than the maximum string or blob length, then
** raise an SQLITE_TOOBIG exception and return NULL.
static void *contextMalloc(sqlite3_context *context, i64 nByte){
  sqlite3 *db = sqlite3_context_db_handle(context);
  assert( nByte>0 );
  testcase( nByte==db->aLimit[SQLITE_LIMIT_LENGTH] );
  testcase( nByte==db->aLimit[SQLITE_LIMIT_LENGTH]+1 );
  if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
    sqlite3_result_error_toobig(context);
    z = sqlite3Malloc(nByte);
    if( !z ){
      sqlite3_result_error_nomem(context);
  return z;
** Implementation of the upper() and lower() SQL functions.
static void upperFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
  char *z1;
  const char *z2;
  int i, n;
  UNUSED_PARAMETER(argc);
  z2 = (char*)sqlite3_value_text(argv[0]);
  n = sqlite3_value_bytes(argv[0]);
  /* Verify that the call to _bytes() does not invalidate the _text() pointer */
  assert( z2==(char*)sqlite3_value_text(argv[0]) );
  if( z2 ){
    z1 = contextMalloc(context, ((i64)n)+1);
    if( z1 ){
      for(i=0; i<n; i++){
        z1[i] = (char)sqlite3Toupper(z2[i]);
      sqlite3_result_text(context, z1, n, sqlite3_free);
static void lowerFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
  char *z1;
  const char *z2;
  int i, n;
  UNUSED_PARAMETER(argc);
  z2 = (char*)sqlite3_value_text(argv[0]);
  n = sqlite3_value_bytes(argv[0]);
  /* Verify that the call to _bytes() does not invalidate the _text() pointer */
  assert( z2==(char*)sqlite3_value_text(argv[0]) );
  if( z2 ){
    z1 = contextMalloc(context, ((i64)n)+1);
    if( z1 ){
      for(i=0; i<n; i++){
        z1[i] = sqlite3Tolower(z2[i]);
      sqlite3_result_text(context, z1, n, sqlite3_free);
** Some functions like COALESCE() and IFNULL() and UNLIKELY() are implemented
** as VDBE code so that unused argument values do not have to be computed.
** However, we still need some kind of function implementation for this
** routines in the function table.  The noopFunc macro provides this.
** noopFunc will never be called so it doesn't matter what the implementation
** is.  We might as well use the "version()" function as a substitute.
#define noopFunc versionFunc   /* Substitute function - never called */
** Implementation of random().  Return a random integer. 
static void randomFunc(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **NotUsed2
  sqlite_int64 r;
  UNUSED_PARAMETER2(NotUsed, NotUsed2);
  sqlite3_randomness(sizeof(r), &r);
  if( r<0 ){
    /* We need to prevent a random number of 0x8000000000000000
    ** (or -9223372036854775808) since when you do abs() of that
    ** number of you get the same value back again.  To do this
    ** in a way that is testable, mask the sign bit off of negative
    ** values, resulting in a positive value.  Then take the
    ** 2s complement of that positive value.  The end result can
    ** therefore be no less than -9223372036854775807.
    r = -(r & LARGEST_INT64);
  sqlite3_result_int64(context, r);
** Implementation of randomblob(N).  Return a random blob
** that is N bytes long.
static void randomBlob(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
  sqlite3_int64 n;
  unsigned char *p;
  assert( argc==1 );
  UNUSED_PARAMETER(argc);
  n = sqlite3_value_int64(argv[0]);
  if( n<1 ){
  p = contextMalloc(context, n);
    sqlite3_randomness(n, p);
    sqlite3_result_blob(context, (char*)p, n, sqlite3_free);
** Implementation of the last_insert_rowid() SQL function.  The return
** value is the same as the sqlite3_last_insert_rowid() API function.
static void last_insert_rowid(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **NotUsed2
  sqlite3 *db = sqlite3_context_db_handle(context);
  UNUSED_PARAMETER2(NotUsed, NotUsed2);
  /* IMP: R-51513-12026 The last_insert_rowid() SQL function is a
  ** wrapper around the sqlite3_last_insert_rowid() C/C++ interface
  ** function. */
  sqlite3_result_int64(context, sqlite3_last_insert_rowid(db));
** Implementation of the changes() SQL function.
** IMP: R-32760-32347 The changes() SQL function is a wrapper
** around the sqlite3_changes64() C/C++ function and hence follows the
** same rules for counting changes.
*/
static void changes(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **NotUsed2
  sqlite3 *db = sqlite3_context_db_handle(context);
  UNUSED_PARAMETER2(NotUsed, NotUsed2);
  sqlite3_result_int64(context, sqlite3_changes64(db));
** Implementation of the total_changes() SQL function.  The return value is
** the same as the sqlite3_total_changes64() API function.
static void total_changes(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **NotUsed2
  sqlite3 *db = sqlite3_context_db_handle(context);
  UNUSED_PARAMETER2(NotUsed, NotUsed2);
  /* IMP: R-11217-42568 This function is a wrapper around the
  ** sqlite3_total_changes64() C/C++ interface. */
  sqlite3_result_int64(context, sqlite3_total_changes64(db));
** A structure defining how to do GLOB-style comparisons.
struct compareInfo {
  u8 matchAll;          /* "*" or "%" */
  u8 matchOne;          /* "?" or "_" */
  u8 matchSet;          /* "[" or 0 */
  u8 noCase;            /* true to ignore case differences */
** For LIKE and GLOB matching on EBCDIC machines, assume that every
** character is exactly one byte in size.  Also, provide the Utf8Read()
** macro for fast reading of the next character in the common case where
** the next character is ASCII.
#if defined(SQLITE_EBCDIC)
# define sqlite3Utf8Read(A)        (*((*A)++))
# define Utf8Read(A)               (*(A++))
# define Utf8Read(A)               (A[0]<0x80?*(A++):sqlite3Utf8Read(&A))
static const struct compareInfo globInfo = { '*', '?', '[', 0 };
/* The correct SQL-92 behavior is for the LIKE operator to ignore
** case.  Thus  'a' LIKE 'A' would be true. */
static const struct compareInfo likeInfoNorm = { '%', '_',   0, 1 };
/* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator
** is case sensitive causing 'a' LIKE 'A' to be false */
static const struct compareInfo likeInfoAlt = { '%', '_',   0, 0 };
** Possible error returns from patternMatch()
#define SQLITE_MATCH             0
#define SQLITE_NOMATCH           1
#define SQLITE_NOWILDCARDMATCH   2
** Compare two UTF-8 strings for equality where the first string is
** a GLOB or LIKE expression.  Return values:
**    SQLITE_MATCH:            Match
**    SQLITE_NOMATCH:          No match
**    SQLITE_NOWILDCARDMATCH:  No match in spite of having * or % wildcards.
** 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.
** Like matching rules:
**      '%'       Matches any sequence of zero or more characters
***     '_'       Matches any one character
**      Ec        Where E is the "esc" character and c is any other
**                character, including '%', '_', and esc, match exactly c.
** The comments within this routine usually assume glob matching.
** This routine is usually quick, but can be N**2 in the worst case.
static int patternCompare(
  const u8 *zPattern,              /* The glob pattern */
  const u8 *zString,               /* The string to compare against the glob */
  const struct compareInfo *pInfo, /* Information about how to do the compare */
  u32 matchOther                   /* The escape char (LIKE) or '[' (GLOB) */
  u32 c, c2;                       /* Next pattern and input string chars */
  u32 matchOne = pInfo->matchOne;  /* "?" or "_" */
  u32 matchAll = pInfo->matchAll;  /* "*" or "%" */
  u8 noCase = pInfo->noCase;       /* True if uppercase==lowercase */
  const u8 *zEscaped = 0;          /* One past the last escaped input char */
  while( (c = Utf8Read(zPattern))!=0 ){
    if( c==matchAll ){  /* Match "*" */
      /* Skip over multiple "*" characters in the pattern.  If there
      ** are also "?" characters, skip those as well, but consume a
      ** single character of the input string for each "?" skipped */
      while( (c=Utf8Read(zPattern)) == matchAll
             || (c == matchOne && matchOne!=0) ){
        if( c==matchOne && sqlite3Utf8Read(&zString)==0 ){
          return SQLITE_NOWILDCARDMATCH;
      if( c==0 ){
        return SQLITE_MATCH;   /* "*" at the end of the pattern matches */
      }else if( c==matchOther ){
        if( pInfo->matchSet==0 ){
          c = sqlite3Utf8Read(&zPattern);
          if( c==0 ) return SQLITE_NOWILDCARDMATCH;
        }else{
          /* "[...]" immediately follows the "*".  We have to do a slow
          ** recursive search in this case, but it is an unusual case. */
          assert( matchOther<0x80 );  /* '[' is a single-byte character */
          while( *zString ){
            int bMatch = patternCompare(&zPattern[-1],zString,pInfo,matchOther);
            if( bMatch!=SQLITE_NOMATCH ) return bMatch;
            SQLITE_SKIP_UTF8(zString);
          return SQLITE_NOWILDCARDMATCH;
      /* At this point variable c contains the first character of the
      ** pattern string past the "*".  Search in the input string for the
      ** first matching character and recursively continue the match from
      ** that point.
      ** For a case-insensitive search, set variable cx to be the same as
      ** c but in the other case and search the input string for either
      ** c or cx.
      if( c<0x80 ){
        char zStop[3];
        int bMatch;
        if( noCase ){
          zStop[0] = sqlite3Toupper(c);
          zStop[1] = sqlite3Tolower(c);
          zStop[2] = 0;
        }else{
          zStop[0] = c;
          zStop[1] = 0;
        while(1){
          zString += strcspn((const char*)zString, zStop);
          if( zString[0]==0 ) break;
          zString++;
          bMatch = patternCompare(zPattern,zString,pInfo,matchOther);
          if( bMatch!=SQLITE_NOMATCH ) return bMatch;
      }else{
        int bMatch;
        while( (c2 = Utf8Read(zString))!=0 ){
          if( c2!=c ) continue;
          bMatch = patternCompare(zPattern,zString,pInfo,matchOther);
          if( bMatch!=SQLITE_NOMATCH ) return bMatch;
      return SQLITE_NOWILDCARDMATCH;
    if( c==matchOther ){
      if( pInfo->matchSet==0 ){
        c = sqlite3Utf8Read(&zPattern);
        if( c==0 ) return SQLITE_NOMATCH;
        zEscaped = zPattern;
      }else{
        u32 prior_c = 0;
        int seen = 0;
        int invert = 0;
        c = sqlite3Utf8Read(&zString);
        if( c==0 ) return SQLITE_NOMATCH;
        c2 = sqlite3Utf8Read(&zPattern);
        if( c2=='^' ){
          invert = 1;
          c2 = sqlite3Utf8Read(&zPattern);
        if( c2==']' ){
          if( c==']' ) seen = 1;
          c2 = sqlite3Utf8Read(&zPattern);
        while( c2 && c2!=']' ){
          if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){
            c2 = sqlite3Utf8Read(&zPattern);
            if( c>=prior_c && c<=c2 ) seen = 1;
            prior_c = 0;
          }else{
            if( c==c2 ){
              seen = 1;
            prior_c = c2;
          c2 = sqlite3Utf8Read(&zPattern);
        if( c2==0 || (seen ^ invert)==0 ){
          return SQLITE_NOMATCH;
        continue;
    c2 = Utf8Read(zString);
    if( c==c2 ) continue;
    if( noCase  && sqlite3Tolower(c)==sqlite3Tolower(c2) && c<0x80 && c2<0x80 ){
      continue;
    if( c==matchOne && zPattern!=zEscaped && c2!=0 ) continue;
    return SQLITE_NOMATCH;
  return *zString==0 ? SQLITE_MATCH : SQLITE_NOMATCH;
** The sqlite3_strglob() interface.  Return 0 on a match (like strcmp()) and
** non-zero if there is no match.
int sqlite3_strglob(const char *zGlobPattern, const char *zString){
  if( zString==0 ){
    return zGlobPattern!=0;
  }else if( zGlobPattern==0 ){
    return 1;
    return patternCompare((u8*)zGlobPattern, (u8*)zString, &globInfo, '[');
** The sqlite3_strlike() interface.  Return 0 on a match and non-zero for
** a miss - like strcmp().
int sqlite3_strlike(const char *zPattern, const char *zStr, unsigned int esc){
  if( zStr==0 ){
    return zPattern!=0;
  }else if( zPattern==0 ){
    return 1;
    return patternCompare((u8*)zPattern, (u8*)zStr, &likeInfoNorm, esc);
** Count the number of times that the LIKE operator (or GLOB which is
** just a variation of LIKE) gets called.  This is used for testing
#ifdef SQLITE_TEST
int sqlite3_like_count = 0;
** Implementation of the like() SQL function.  This function implements
** the built-in LIKE operator.  The first argument to the function is the
** pattern and the second argument is the string.  So, the SQL statements:
**       A LIKE B
** is implemented as like(B,A).
** This same function (with a different compareInfo structure) computes
** the GLOB operator.
static void likeFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
  const unsigned char *zA, *zB;
  u32 escape;
  int nPat;
  sqlite3 *db = sqlite3_context_db_handle(context);
  struct compareInfo *pInfo = sqlite3_user_data(context);
  struct compareInfo backupInfo;
#ifdef SQLITE_LIKE_DOESNT_MATCH_BLOBS
  if( sqlite3_value_type(argv[0])==SQLITE_BLOB
   || sqlite3_value_type(argv[1])==SQLITE_BLOB
#ifdef SQLITE_TEST
    sqlite3_like_count++;
    sqlite3_result_int(context, 0);
    return;
  /* Limit the length of the LIKE or GLOB pattern to avoid problems
  ** of deep recursion and N*N behavior in patternCompare().
  nPat = sqlite3_value_bytes(argv[0]);
  testcase( nPat==db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] );
  testcase( nPat==db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]+1 );
  if( nPat > db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] ){
    sqlite3_result_error(context, "LIKE or GLOB pattern too complex", -1);
    return;
  if( argc==3 ){
    /* The escape character string must consist of a single UTF-8 character.
    ** Otherwise, return an error.
    const unsigned char *zEsc = sqlite3_value_text(argv[2]);
    if( zEsc==0 ) return;
    if( sqlite3Utf8CharLen((char*)zEsc, -1)!=1 ){
      sqlite3_result_error(context,
          "ESCAPE expression must be a single character", -1);
      return;
    escape = sqlite3Utf8Read(&zEsc);
    if( escape==pInfo->matchAll || escape==pInfo->matchOne ){
      memcpy(&backupInfo, pInfo, sizeof(backupInfo));
      pInfo = &backupInfo;
      if( escape==pInfo->matchAll ) pInfo->matchAll = 0;
      if( escape==pInfo->matchOne ) pInfo->matchOne = 0;
    escape = pInfo->matchSet;
  zB = sqlite3_value_text(argv[0]);
  zA = sqlite3_value_text(argv[1]);
  if( zA && zB ){
#ifdef SQLITE_TEST
    sqlite3_like_count++;
    sqlite3_result_int(context,
                      patternCompare(zB, zA, pInfo, escape)==SQLITE_MATCH);
** Implementation of the NULLIF(x,y) function.  The result is the first
** argument if the arguments are different.  The result is NULL if the
** arguments are equal to each other.
static void nullifFunc(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **argv
  CollSeq *pColl = sqlite3GetFuncCollSeq(context);
  UNUSED_PARAMETER(NotUsed);
  if( sqlite3MemCompare(argv[0], argv[1], pColl)!=0 ){
    sqlite3_result_value(context, argv[0]);
** Implementation of the sqlite_version() function.  The result is the version
** of the SQLite library that is running.
static void versionFunc(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **NotUsed2
  UNUSED_PARAMETER2(NotUsed, NotUsed2);

2F52
  /* IMP: R-48699-48617 This function is an SQL wrapper around the
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