** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.227 2009/04/02 09:07:13 drh Exp $
*/
#include "sqliteInt.h"
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"

/*
................................................................................
  sqlite3_result_double(context, r);
}
#endif

/*
** Allocate nByte bytes of space using sqlite3_malloc(). If the
** allocation fails, call sqlite3_result_error_nomem() to notify
** the database handle that malloc() has failed.


*/
static void *contextMalloc(sqlite3_context *context, i64 nByte){
  char *z;

  assert( nByte>0 );


  if( nByte>sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH] ){
    sqlite3_result_error_toobig(context);
    z = 0;
  }else{
    z = sqlite3Malloc((int)nByte);
    if( !z ){
      sqlite3_result_error_nomem(context);
    }
................................................................................
static void likeFunc(
  sqlite3_context *context, 
  int argc, 
  sqlite3_value **argv
){
  const unsigned char *zA, *zB;
  int escape = 0;

  sqlite3 *db = sqlite3_context_db_handle(context);

  zB = sqlite3_value_text(argv[0]);
  zA = sqlite3_value_text(argv[1]);

  /* Limit the length of the LIKE or GLOB pattern to avoid problems
  ** of deep recursion and N*N behavior in patternCompare().
  */
  if( sqlite3_value_bytes(argv[0]) >


        db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] ){
    sqlite3_result_error(context, "LIKE or GLOB pattern too complex", -1);
    return;
  }
  assert( zB==sqlite3_value_text(argv[0]) );  /* Encoding did not change */

  if( argc==3 ){
    /* The escape character string must consist of a single UTF-8 character.
................................................................................
*/
static void zeroblobFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  i64 n;

  assert( argc==1 );
  UNUSED_PARAMETER(argc);
  n = sqlite3_value_int64(argv[0]);


  if( n>sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH] ){
    sqlite3_result_error_toobig(context);
  }else{
    sqlite3_result_zeroblob(context, (int)n);
  }
}

/*
................................................................................
  for(i=j=0; i<=loopLimit; i++){
    if( zStr[i]!=zPattern[0] || memcmp(&zStr[i], zPattern, nPattern) ){
      zOut[j++] = zStr[i];
    }else{
      u8 *zOld;
      sqlite3 *db = sqlite3_context_db_handle(context);
      nOut += nRep - nPattern;


      if( nOut>=db->aLimit[SQLITE_LIMIT_LENGTH] ){
        sqlite3_result_error_toobig(context);
        sqlite3DbFree(db, zOut);
        return;
      }
      zOld = zOut;
      zOut = sqlite3_realloc(zOut, (int)nOut);
      if( zOut==0 ){
................................................................................
  if( nChar>0 ){
    flags = SQLITE_PTR_TO_INT(sqlite3_user_data(context));
    if( flags & 1 ){
      while( nIn>0 ){
        int len = 0;
        for(i=0; i<nChar; i++){
          len = aLen[i];
          if( memcmp(zIn, azChar[i], len)==0 ) break;
        }
        if( i>=nChar ) break;
        zIn += len;
        nIn -= len;
      }
    }
    if( flags & 2 ){

** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.228 2009/04/02 10:16:18 drh Exp $
*/
#include "sqliteInt.h"
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"

/*
................................................................................
  sqlite3_result_double(context, r);
}
#endif

/*
** Allocate nByte bytes of space using sqlite3_malloc(). 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){
  char *z;
  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 = 0;
  }else{
    z = sqlite3Malloc((int)nByte);
    if( !z ){
      sqlite3_result_error_nomem(context);
    }
................................................................................
static void likeFunc(
  sqlite3_context *context, 
  int argc, 
  sqlite3_value **argv
){
  const unsigned char *zA, *zB;
  int escape = 0;
  int nPat;
  sqlite3 *db = sqlite3_context_db_handle(context);

  zB = sqlite3_value_text(argv[0]);
  zA = sqlite3_value_text(argv[1]);

  /* 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;
  }
  assert( zB==sqlite3_value_text(argv[0]) );  /* Encoding did not change */

  if( argc==3 ){
    /* The escape character string must consist of a single UTF-8 character.
................................................................................
*/
static void zeroblobFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  i64 n;
  sqlite3 *db = sqlite3_context_db_handle(context);
  assert( argc==1 );
  UNUSED_PARAMETER(argc);
  n = sqlite3_value_int64(argv[0]);
  testcase( n==db->aLimit[SQLITE_LIMIT_LENGTH] );
  testcase( n==db->aLimit[SQLITE_LIMIT_LENGTH]+1 );
  if( n>db->aLimit[SQLITE_LIMIT_LENGTH] ){
    sqlite3_result_error_toobig(context);
  }else{
    sqlite3_result_zeroblob(context, (int)n);
  }
}

/*
................................................................................
  for(i=j=0; i<=loopLimit; i++){
    if( zStr[i]!=zPattern[0] || memcmp(&zStr[i], zPattern, nPattern) ){
      zOut[j++] = zStr[i];
    }else{
      u8 *zOld;
      sqlite3 *db = sqlite3_context_db_handle(context);
      nOut += nRep - nPattern;
      testcase( nOut-1==db->aLimit[SQLITE_LIMIT_LENGTH] );
      testcase( nOut-2==db->aLimit[SQLITE_LIMIT_LENGTH] );
      if( nOut-1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
        sqlite3_result_error_toobig(context);
        sqlite3DbFree(db, zOut);
        return;
      }
      zOld = zOut;
      zOut = sqlite3_realloc(zOut, (int)nOut);
      if( zOut==0 ){
................................................................................
  if( nChar>0 ){
    flags = SQLITE_PTR_TO_INT(sqlite3_user_data(context));
    if( flags & 1 ){
      while( nIn>0 ){
        int len = 0;
        for(i=0; i<nChar; i++){
          len = aLen[i];
          if( len<=nIn && memcmp(zIn, azChar[i], len)==0 ) break;
        }
        if( i>=nChar ) break;
        zIn += len;
        nIn -= len;
      }
    }
    if( flags & 2 ){