** 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 1.156 2007/05/15 01:13:47 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
/* #include <math.h> */
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"
................................................................................
    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]);
      if( z==0 ) return;
      for(len=0; *z; z++){ if( (0xc0&*z)!=0x80 ) len++; }




      sqlite3_result_int(context, len);
      break;
    }
    default: {
      sqlite3_result_null(context);
      break;
    }
................................................................................
static void substrFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const unsigned char *z;
  const unsigned char *z2;
  int i;
  int len;
  int p0type;
  i64 p1, p2;

  assert( argc==3 );
  p0type = sqlite3_value_type(argv[0]);
  if( p0type==SQLITE_BLOB ){
    len = sqlite3_value_bytes(argv[0]);
    z = sqlite3_value_blob(argv[0]);
    if( z==0 ) return;
  }else{
    z = sqlite3_value_text(argv[0]);
    if( z==0 ) return;
    for(len=0, z2=z; *z2; z2++){ if( (0xc0&*z2)!=0x80 ) len++; }



  }
  p1 = sqlite3_value_int(argv[1]);
  p2 = sqlite3_value_int(argv[2]);
  if( p1<0 ){
    p1 += len;
    if( p1<0 ){
      p2 += p1;
................................................................................
  }else if( p1>0 ){
    p1--;
  }
  if( p1+p2>len ){
    p2 = len-p1;
  }
  if( p0type!=SQLITE_BLOB ){
    for(i=0; i<p1 && z[i]; i++){
      if( (z[i]&0xc0)==0x80 ) p1++;

    }
    while( z[i] && (z[i]&0xc0)==0x80 ){ i++; p1++; }
    for(; i<p1+p2 && z[i]; i++){
      if( (z[i]&0xc0)==0x80 ) p2++;
    }
    while( z[i] && (z[i]&0xc0)==0x80 ){ i++; p2++; }
    if( p2<0 ) p2 = 0;
    sqlite3_result_text(context, (char*)&z[p1], p2, SQLITE_TRANSIENT);
  }else{
    if( p2<0 ) p2 = 0;
    sqlite3_result_blob(context, (char*)&z[p1], p2, SQLITE_TRANSIENT);
  }
}

/*
................................................................................
** 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 };

/*
** 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)   sqlite3ReadUtf8(X)


/*
** 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:
................................................................................
  int prevEscape = 0;     /* True if the previous character was 'escape' */

  while( (c = *zPattern)!=0 ){
    if( !prevEscape && c==matchAll ){
      while( (c=zPattern[1]) == matchAll || c == matchOne ){
        if( c==matchOne ){
          if( *zString==0 ) return 0;
          sqliteNextChar(zString);
        }
        zPattern++;
      }
      if( c && esc && sqlite3ReadUtf8(&zPattern[1])==esc ){
        u8 const *zTemp = &zPattern[1];
        sqliteNextChar(zTemp);
        c = *zTemp;
      }
      if( c==0 ) return 1;
      if( c==matchSet ){
        assert( esc==0 );   /* This is GLOB, not LIKE */
        while( *zString && patternCompare(&zPattern[1],zString,pInfo,esc)==0 ){
          sqliteNextChar(zString);
        }
        return *zString!=0;
      }else{
        while( (c2 = *zString)!=0 ){
          if( noCase ){
            c2 = sqlite3UpperToLower[c2];
            c = sqlite3UpperToLower[c];
            while( c2 != 0 && c2 != c ){ c2 = sqlite3UpperToLower[*++zString]; }
          }else{
            while( c2 != 0 && c2 != c ){ c2 = *++zString; }
          }
          if( c2==0 ) return 0;
          if( patternCompare(&zPattern[1],zString,pInfo,esc) ) return 1;
          sqliteNextChar(zString);
        }
        return 0;
      }
    }else if( !prevEscape && c==matchOne ){
      if( *zString==0 ) return 0;
      sqliteNextChar(zString);
      zPattern++;
    }else if( c==matchSet ){
      int prior_c = 0;
      assert( esc==0 );    /* This only occurs for GLOB, not LIKE */
      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++;
    }else if( esc && !prevEscape && sqlite3ReadUtf8(zPattern)==esc){
      prevEscape = 1;
      sqliteNextChar(zPattern);
    }else{
      if( noCase ){
        if( sqlite3UpperToLower[c] != sqlite3UpperToLower[*zString] ) return 0;
      }else{
        if( c != *zString ) return 0;
      }
      zPattern++;
................................................................................
    azChar = azOne;
    zCharSet = 0;
  }else if( (zCharSet = sqlite3_value_text(argv[1]))==0 ){
    return;
  }else{
    const unsigned char *z;
    for(z=zCharSet, nChar=0; *z; nChar++){
      sqliteNextChar(z);
    }
    if( nChar>0 ){
      azChar = sqlite3_malloc( nChar*(sizeof(char*)+1) );
      if( azChar==0 ){
        return;
      }
      aLen = (unsigned char*)&azChar[nChar];
      for(z=zCharSet, nChar=0; *z; nChar++){
        azChar[nChar] = z;
        sqliteNextChar(z);
        aLen[nChar] = z - azChar[nChar];
      }
    }
  }
  if( nChar>0 ){
    flags = (int)sqlite3_user_data(context);
    if( flags & 1 ){

** 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 1.157 2007/05/15 11:55:09 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
/* #include <math.h> */
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"
................................................................................
    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]);
      if( z==0 ) return;
      len = 0;
      while( *z ){
        len++;
        SQLITE_SKIP_UTF8(z);
      }
      sqlite3_result_int(context, len);
      break;
    }
    default: {
      sqlite3_result_null(context);
      break;
    }
................................................................................
static void substrFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const unsigned char *z;
  const unsigned char *z2;

  int len;
  int p0type;
  i64 p1, p2;

  assert( argc==3 );
  p0type = sqlite3_value_type(argv[0]);
  if( p0type==SQLITE_BLOB ){
    len = sqlite3_value_bytes(argv[0]);
    z = sqlite3_value_blob(argv[0]);
    if( z==0 ) return;
  }else{
    z = sqlite3_value_text(argv[0]);
    if( z==0 ) return;
    len = 0;
    for(z2=z; *z2; len++){
      SQLITE_SKIP_UTF8(z2);
    }
  }
  p1 = sqlite3_value_int(argv[1]);
  p2 = sqlite3_value_int(argv[2]);
  if( p1<0 ){
    p1 += len;
    if( p1<0 ){
      p2 += p1;
................................................................................
  }else if( p1>0 ){
    p1--;
  }
  if( p1+p2>len ){
    p2 = len-p1;
  }
  if( p0type!=SQLITE_BLOB ){
    while( *z && p1 ){
      SQLITE_SKIP_UTF8(z);
      p1--;
    }

    for(z2=z; *z2 && p2; p2--){
      SQLITE_SKIP_UTF8(z2);
    }


    sqlite3_result_text(context, (char*)z, z2-z, SQLITE_TRANSIENT);
  }else{
    if( p2<0 ) p2 = 0;
    sqlite3_result_blob(context, (char*)&z[p1], p2, SQLITE_TRANSIENT);
  }
}

/*
................................................................................
** 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 };

/*
** Read a single UTF-8 character and return its value.
*/
u32 sqlite3ReadUtf8(const unsigned char *z){
  u32 c;
  SQLITE_READ_UTF8(z, c);
  return c;
}

/*
** 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:
................................................................................
  int prevEscape = 0;     /* True if the previous character was 'escape' */

  while( (c = *zPattern)!=0 ){
    if( !prevEscape && c==matchAll ){
      while( (c=zPattern[1]) == matchAll || c == matchOne ){
        if( c==matchOne ){
          if( *zString==0 ) return 0;
          SQLITE_SKIP_UTF8(zString);
        }
        zPattern++;
      }
      if( c && esc && sqlite3ReadUtf8(&zPattern[1])==esc ){
        u8 const *zTemp = &zPattern[1];
        SQLITE_SKIP_UTF8(zTemp);
        c = *zTemp;
      }
      if( c==0 ) return 1;
      if( c==matchSet ){
        assert( esc==0 );   /* This is GLOB, not LIKE */
        while( *zString && patternCompare(&zPattern[1],zString,pInfo,esc)==0 ){
          SQLITE_SKIP_UTF8(zString);
        }
        return *zString!=0;
      }else{
        while( (c2 = *zString)!=0 ){
          if( noCase ){
            c2 = sqlite3UpperToLower[c2];
            c = sqlite3UpperToLower[c];
            while( c2 != 0 && c2 != c ){ c2 = sqlite3UpperToLower[*++zString]; }
          }else{
            while( c2 != 0 && c2 != c ){ c2 = *++zString; }
          }
          if( c2==0 ) return 0;
          if( patternCompare(&zPattern[1],zString,pInfo,esc) ) return 1;
          SQLITE_SKIP_UTF8(zString);
        }
        return 0;
      }
    }else if( !prevEscape && c==matchOne ){
      if( *zString==0 ) return 0;
      SQLITE_SKIP_UTF8(zString);
      zPattern++;
    }else if( c==matchSet ){
      int prior_c = 0;
      assert( esc==0 );    /* This only occurs for GLOB, not LIKE */
      seen = 0;
      invert = 0;
      c = sqlite3ReadUtf8(zString);
      if( c==0 ) return 0;
      c2 = *++zPattern;
      if( c2=='^' ){ invert = 1; c2 = *++zPattern; }
      if( c2==']' ){
        if( c==']' ) seen = 1;
        c2 = *++zPattern;
      }
      while( (c2 = sqlite3ReadUtf8(zPattern))!=0 && c2!=']' ){
        if( c2=='-' && zPattern[1]!=']' && zPattern[1]!=0 && prior_c>0 ){
          zPattern++;
          c2 = sqlite3ReadUtf8(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;
        }
        SQLITE_SKIP_UTF8(zPattern);
      }
      if( c2==0 || (seen ^ invert)==0 ) return 0;
      SQLITE_SKIP_UTF8(zString);
      zPattern++;
    }else if( esc && !prevEscape && sqlite3ReadUtf8(zPattern)==esc){
      prevEscape = 1;
      SQLITE_SKIP_UTF8(zPattern);
    }else{
      if( noCase ){
        if( sqlite3UpperToLower[c] != sqlite3UpperToLower[*zString] ) return 0;
      }else{
        if( c != *zString ) return 0;
      }
      zPattern++;
................................................................................
    azChar = azOne;
    zCharSet = 0;
  }else if( (zCharSet = sqlite3_value_text(argv[1]))==0 ){
    return;
  }else{
    const unsigned char *z;
    for(z=zCharSet, nChar=0; *z; nChar++){
      SQLITE_SKIP_UTF8(z);
    }
    if( nChar>0 ){
      azChar = sqlite3_malloc( nChar*(sizeof(char*)+1) );
      if( azChar==0 ){
        return;
      }
      aLen = (unsigned char*)&azChar[nChar];
      for(z=zCharSet, nChar=0; *z; nChar++){
        azChar[nChar] = z;
        SQLITE_SKIP_UTF8(z);
        aLen[nChar] = z - azChar[nChar];
      }
    }
  }
  if( nChar>0 ){
    flags = (int)sqlite3_user_data(context);
    if( flags & 1 ){

**    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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.566 2007/05/12 12:08:51 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_
#include "limits.h"


#if defined(SQLITE_TCL) || defined(TCLSH)
................................................................................

/*
 * This global flag is set for performance testing of triggers. When it is set
 * SQLite will perform the overhead of building new and old trigger references 
 * even when no triggers exist
 */
extern int sqlite3_always_code_trigger_setup;


























































/*
** The SQLITE_CORRUPT_BKPT macro can be either a constant (for production
** builds) or a function call (for debugging).  If it is a function call,
** it allows the operator to set a breakpoint at the spot where database
** corruption is first detected.
*/
................................................................................
int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
int sqlite3AtoF(const char *z, double*);
char *sqlite3_snprintf(int,char*,const char*,...);
int sqlite3GetInt32(const char *, int*);
int sqlite3FitsIn64Bits(const char *);
int sqlite3Utf16ByteLen(const void *pData, int nChar);
int sqlite3Utf8CharLen(const char *pData, int nByte);
int sqlite3ReadUtf8(const unsigned char *);
int sqlite3PutVarint(unsigned char *, u64);
int sqlite3GetVarint(const unsigned char *, u64 *);
int sqlite3GetVarint32(const unsigned char *, u32 *);
int sqlite3VarintLen(u64 v);
void sqlite3IndexAffinityStr(Vdbe *, Index *);
void sqlite3TableAffinityStr(Vdbe *, Table *);
char sqlite3CompareAffinity(Expr *pExpr, char aff2);

**    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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.567 2007/05/15 11:55:09 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_
#include "limits.h"


#if defined(SQLITE_TCL) || defined(TCLSH)
................................................................................

/*
 * This global flag is set for performance testing of triggers. When it is set
 * SQLite will perform the overhead of building new and old trigger references 
 * even when no triggers exist
 */
extern int sqlite3_always_code_trigger_setup;

/*
** A lookup table used by the SQLITE_READ_UTF8 macro.  The definition
** is in utf.c.
*/
extern const unsigned char sqlite3UtfTrans1[];

/*
** Macros for reading UTF8 characters.
**
** SQLITE_READ_UTF8(x,c) reads a single UTF8 value out of x and writes
** that value into c.  The type of x must be unsigned char*.  The type
** of c must be unsigned int.
**
** SQLITE_SKIP_UTF8(x) advances x forward by one character.  The type of
** x must be unsigned char*.
**
** Notes On Invalid UTF-8:
**
**  *  These macros never allow a 7-bit character (0x00 through 0x7f) to
**     be encoded as a multi-byte character.  Any multi-byte character that
**     attempts to encode a value between 0x00 and 0x7f is rendered as 0xfffd.
**
**  *  These macros never allow a UTF16 surragate value to be encoded.
**     If a multi-byte character attempts to encode a value between
**     0xd800 and 0xe000 then it is rendered as 0xfffd.
**
**  *  Bytes in the range of 0x80 through 0xbf which occur as the first
**     byte of a character are interpreted as single-byte characters
**     and rendered as themselves even though they are technically
**     invalid characters.
**
**  *  These routines accept an infinite number of different UTF8 encodings
**     for unicode values 0x80 and greater.  They do not change over-length
**     encodings to 0xfffd as some systems recommend.
** 
*/
#define SQLITE_READ_UTF8(zIn, c) {                     \
  c = *(zIn++);                                        \
  if( c>=0xc0 ){                                       \
    c = sqlite3UtfTrans1[c-0xc0];                      \
    while( (*zIn & 0xc0)==0x80 ){                      \
      c = (c<<6) + (0x3f & *(zIn++));                  \
    }                                                  \
    if( c<0x80                                         \
        || (c&0xFFFFF800)==0xD800                      \
        || (c&0xFFFFFFFE)==0xFFFE ){  c = 0xFFFD; }    \
  }                                                    \
}
#define SQLITE_SKIP_UTF8(zIn) {                        \
  if( (*(zIn++))>=0xc0 ){                              \
    while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
  }                                                    \
}




/*
** The SQLITE_CORRUPT_BKPT macro can be either a constant (for production
** builds) or a function call (for debugging).  If it is a function call,
** it allows the operator to set a breakpoint at the spot where database
** corruption is first detected.
*/
................................................................................
int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
int sqlite3AtoF(const char *z, double*);
char *sqlite3_snprintf(int,char*,const char*,...);
int sqlite3GetInt32(const char *, int*);
int sqlite3FitsIn64Bits(const char *);
int sqlite3Utf16ByteLen(const void *pData, int nChar);
int sqlite3Utf8CharLen(const char *pData, int nByte);
u32 sqlite3ReadUtf8(const unsigned char *);
int sqlite3PutVarint(unsigned char *, u64);
int sqlite3GetVarint(const unsigned char *, u64 *);
int sqlite3GetVarint32(const unsigned char *, u32 *);
int sqlite3VarintLen(u64 v);
void sqlite3IndexAffinityStr(Vdbe *, Index *);
void sqlite3TableAffinityStr(Vdbe *, Table *);
char sqlite3CompareAffinity(Expr *pExpr, char aff2);

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used to translate between UTF-8, 
** UTF-16, UTF-16BE, and UTF-16LE.
**
** $Id: utf.c,v 1.46 2007/05/10 17:23:12 drh Exp $
**
** Notes on UTF-8:
**
**   Byte-0    Byte-1    Byte-2    Byte-3    Value
**  0xxxxxxx                                 00000000 00000000 0xxxxxxx
**  110yyyyy  10xxxxxx                       00000000 00000yyy yyxxxxxx
**  1110zzzz  10yyyyyy  10xxxxxx             00000000 zzzzyyyy yyxxxxxx
................................................................................
**  zzzzyyyy yyxxxxxx                        00000000 zzzzyyyy yyxxxxxx
**
**
** BOM or Byte Order Mark:
**     0xff 0xfe   little-endian utf-16 follows
**     0xfe 0xff   big-endian utf-16 follows
**
**
** Handling of malformed strings:
**
** SQLite accepts and processes malformed strings without an error wherever
** possible. However this is not possible when converting between UTF-8 and
** UTF-16.
**
** When converting malformed UTF-8 strings to UTF-16, one instance of the
** replacement character U+FFFD for each byte that cannot be interpeted as
** part of a valid unicode character.
**
** When converting malformed UTF-16 strings to UTF-8, one instance of the
** replacement character U+FFFD for each pair of bytes that cannot be
** interpeted as part of a valid unicode character.
**
** This file contains the following public routines:
**
** sqlite3VdbeMemTranslate() - Translate the encoding used by a Mem* string.
** sqlite3VdbeMemHandleBom() - Handle byte-order-marks in UTF16 Mem* strings.
** sqlite3Utf16ByteLen()     - Calculate byte-length of a void* UTF16 string.
** sqlite3Utf8CharLen()      - Calculate char-length of a char* UTF8 string.
** sqlite3Utf8LikeCompare()  - Do a LIKE match given two UTF8 char* strings.
**
*/
#include "sqliteInt.h"
#include <assert.h>
#include "vdbeInt.h"

/*
** The following constant value is used by the SQLITE_BIGENDIAN and
** SQLITE_LITTLEENDIAN macros.
*/
const int sqlite3one = 1;

/*
** This table maps from the first byte of a UTF-8 character to the number
** of trailing bytes expected. A value '4' indicates that the table key
** is not a legal first byte for a UTF-8 character.
*/

static const u8 xtra_utf8_bytes[256]  = {
/* 0xxxxxxx */
0, 0, 0, 0, 0, 0, 0, 0,     0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,     0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,     0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,     0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,     0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,     0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,     0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,     0, 0, 0, 0, 0, 0, 0, 0,

/* 10wwwwww */
4, 4, 4, 4, 4, 4, 4, 4,     4, 4, 4, 4, 4, 4, 4, 4,
4, 4, 4, 4, 4, 4, 4, 4,     4, 4, 4, 4, 4, 4, 4, 4,
4, 4, 4, 4, 4, 4, 4, 4,     4, 4, 4, 4, 4, 4, 4, 4,
4, 4, 4, 4, 4, 4, 4, 4,     4, 4, 4, 4, 4, 4, 4, 4,

/* 110yyyyy */
1, 1, 1, 1, 1, 1, 1, 1,     1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,     1, 1, 1, 1, 1, 1, 1, 1,

/* 1110zzzz */
2, 2, 2, 2, 2, 2, 2, 2,     2, 2, 2, 2, 2, 2, 2, 2,

/* 11110yyy */
3, 3, 3, 3, 3, 3, 3, 3,     4, 4, 4, 4, 4, 4, 4, 4,
};

/*
** This table maps from the number of trailing bytes in a UTF-8 character
** to an integer constant that is effectively calculated for each character
** read by a naive implementation of a UTF-8 character reader. The code
** in the READ_UTF8 macro explains things best.
*/
static const int xtra_utf8_bits[] =  {
  0,
  12416,          /* (0xC0 << 6) + (0x80) */
  925824,         /* (0xE0 << 12) + (0x80 << 6) + (0x80) */
  63447168        /* (0xF0 << 18) + (0x80 << 12) + (0x80 << 6) + 0x80 */
};

/*
** If a UTF-8 character contains N bytes extra bytes (N bytes follow
** the initial byte so that the total character length is N+1) then
** masking the character with utf8_mask[N] must produce a non-zero
** result.  Otherwise, we have an (illegal) overlong encoding.
*/
static const int utf_mask[] = {
  0x00000000,
  0xffffff80,
  0xfffff800,
  0xffff0000,
};

#define READ_UTF8(zIn, c) { \
  int xtra;                                            \
  c = *(zIn)++;                                        \
  xtra = xtra_utf8_bytes[c];                           \
  switch( xtra ){                                      \
    case 4: c = (int)0xFFFD; break;                    \
    case 3: c = (c<<6) + *(zIn)++;                     \
    case 2: c = (c<<6) + *(zIn)++;                     \
    case 1: c = (c<<6) + *(zIn)++;                     \
    c -= xtra_utf8_bits[xtra];                         \
    if( (utf_mask[xtra]&c)==0                          \
        || (c&0xFFFFF800)==0xD800                      \
        || (c&0xFFFFFFFE)==0xFFFE ){  c = 0xFFFD; }    \
  }                                                    \
}
int sqlite3ReadUtf8(const unsigned char *z){
  int c;
  READ_UTF8(z, c);
  return c;
}

#define SKIP_UTF8(zIn) {                               \
  zIn += (xtra_utf8_bytes[*(u8 *)zIn] + 1);            \
}

#define WRITE_UTF8(zOut, c) {                          \
  if( c<0x00080 ){                                     \
    *zOut++ = (c&0xFF);                                \
  }                                                    \
  else if( c<0x00800 ){                                \
    *zOut++ = 0xC0 + ((c>>6)&0x1F);                    \
................................................................................
  }
  z = zOut;

  if( pMem->enc==SQLITE_UTF8 ){
    if( desiredEnc==SQLITE_UTF16LE ){
      /* UTF-8 -> UTF-16 Little-endian */
      while( zIn<zTerm ){
        READ_UTF8(zIn, c); 
        WRITE_UTF16LE(z, c);
      }
    }else{
      assert( desiredEnc==SQLITE_UTF16BE );
      /* UTF-8 -> UTF-16 Big-endian */
      while( zIn<zTerm ){
        READ_UTF8(zIn, c); 
        WRITE_UTF16BE(z, c);
      }
    }
    pMem->n = z - zOut;
    *z++ = 0;
  }else{
    assert( desiredEnc==SQLITE_UTF8 );
................................................................................
/*
** pZ is a UTF-8 encoded unicode string. If nByte is less than zero,
** return the number of unicode characters in pZ up to (but not including)
** the first 0x00 byte. If nByte is not less than zero, return the
** number of unicode characters in the first nByte of pZ (or up to 
** the first 0x00, whichever comes first).
*/
int sqlite3Utf8CharLen(const char *z, int nByte){
  int r = 0;
  const char *zTerm;

  if( nByte>=0 ){
    zTerm = &z[nByte];
  }else{
    zTerm = (const char *)(-1);
  }
  assert( z<=zTerm );
  while( *z!=0 && z<zTerm ){
    SKIP_UTF8(z);
    r++;
  }
  return r;
}

#ifndef SQLITE_OMIT_UTF16
/*
................................................................................
*/
int sqlite3Utf8To8(unsigned char *zIn){
  unsigned char *zOut = zIn;
  unsigned char *zStart = zIn;
  int c;

  while(1){
    READ_UTF8(zIn, c);
    if( c==0 ) break;
    if( c!=0xfffd ){
      WRITE_UTF8(zOut, c);
    }
  }
  *zOut = 0;
  return zOut - zStart;
................................................................................
  int n;
  unsigned int c;

  for(i=0; i<0x00110000; i++){
    z = zBuf;
    WRITE_UTF8(z, i);
    n = z-zBuf;

    z = zBuf;
    READ_UTF8(z, c);
    t = i;
    if( i>=0xD800 && i<=0xDFFF ) t = 0xFFFD;
    if( (i&0xFFFFFFFE)==0xFFFE ) t = 0xFFFD;
    assert( c==t );
    assert( (z-zBuf)==n );
  }
  for(i=0; i<0x00110000; i++){
    if( i>=0xD800 && i<=0xE000 ) continue;
    z = zBuf;
    WRITE_UTF16LE(z, i);
    n = z-zBuf;

    z = zBuf;
    READ_UTF16LE(z, c);
    assert( c==i );
    assert( (z-zBuf)==n );
  }
  for(i=0; i<0x00110000; i++){
    if( i>=0xD800 && i<=0xE000 ) continue;
    z = zBuf;
    WRITE_UTF16BE(z, i);
    n = z-zBuf;

    z = zBuf;
    READ_UTF16BE(z, c);
    assert( c==i );
    assert( (z-zBuf)==n );
  }
}
#endif /* SQLITE_TEST */
#endif /* SQLITE_OMIT_UTF16 */

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used to translate between UTF-8, 
** UTF-16, UTF-16BE, and UTF-16LE.
**
** $Id: utf.c,v 1.47 2007/05/15 11:55:09 drh Exp $
**
** Notes on UTF-8:
**
**   Byte-0    Byte-1    Byte-2    Byte-3    Value
**  0xxxxxxx                                 00000000 00000000 0xxxxxxx
**  110yyyyy  10xxxxxx                       00000000 00000yyy yyxxxxxx
**  1110zzzz  10yyyyyy  10xxxxxx             00000000 zzzzyyyy yyxxxxxx
................................................................................
**  zzzzyyyy yyxxxxxx                        00000000 zzzzyyyy yyxxxxxx
**
**
** BOM or Byte Order Mark:
**     0xff 0xfe   little-endian utf-16 follows
**     0xfe 0xff   big-endian utf-16 follows
**























*/
#include "sqliteInt.h"
#include <assert.h>
#include "vdbeInt.h"

/*
** The following constant value is used by the SQLITE_BIGENDIAN and
** SQLITE_LITTLEENDIAN macros.
*/
const int sqlite3one = 1;

/*
** This lookup table is used to help decode the first byte of
** a multi-byte UTF8 character.

*/
const unsigned char sqlite3UtfTrans1[] = {
  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
  0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
  0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
  0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
  0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
  0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x00, 0x00,


















};




















































#define WRITE_UTF8(zOut, c) {                          \
  if( c<0x00080 ){                                     \
    *zOut++ = (c&0xFF);                                \
  }                                                    \
  else if( c<0x00800 ){                                \
    *zOut++ = 0xC0 + ((c>>6)&0x1F);                    \
................................................................................
  }
  z = zOut;

  if( pMem->enc==SQLITE_UTF8 ){
    if( desiredEnc==SQLITE_UTF16LE ){
      /* UTF-8 -> UTF-16 Little-endian */
      while( zIn<zTerm ){
        SQLITE_READ_UTF8(zIn, c); 
        WRITE_UTF16LE(z, c);
      }
    }else{
      assert( desiredEnc==SQLITE_UTF16BE );
      /* UTF-8 -> UTF-16 Big-endian */
      while( zIn<zTerm ){
        SQLITE_READ_UTF8(zIn, c); 
        WRITE_UTF16BE(z, c);
      }
    }
    pMem->n = z - zOut;
    *z++ = 0;
  }else{
    assert( desiredEnc==SQLITE_UTF8 );
................................................................................
/*
** pZ is a UTF-8 encoded unicode string. If nByte is less than zero,
** return the number of unicode characters in pZ up to (but not including)
** the first 0x00 byte. If nByte is not less than zero, return the
** number of unicode characters in the first nByte of pZ (or up to 
** the first 0x00, whichever comes first).
*/
int sqlite3Utf8CharLen(const char *zIn, int nByte){
  int r = 0;
  const u8 *z = (const u8*)zIn;
  const u8 *zTerm;
  if( nByte>=0 ){
    zTerm = &z[nByte];
  }else{
    zTerm = (const u8*)(-1);
  }
  assert( z<=zTerm );
  while( *z!=0 && z<zTerm ){
    SQLITE_SKIP_UTF8(z);
    r++;
  }
  return r;
}

#ifndef SQLITE_OMIT_UTF16
/*
................................................................................
*/
int sqlite3Utf8To8(unsigned char *zIn){
  unsigned char *zOut = zIn;
  unsigned char *zStart = zIn;
  int c;

  while(1){
    SQLITE_READ_UTF8(zIn, c);
    if( c==0 ) break;
    if( c!=0xfffd ){
      WRITE_UTF8(zOut, c);
    }
  }
  *zOut = 0;
  return zOut - zStart;
................................................................................
  int n;
  unsigned int c;

  for(i=0; i<0x00110000; i++){
    z = zBuf;
    WRITE_UTF8(z, i);
    n = z-zBuf;
    z[0] = 0;
    z = zBuf;
    SQLITE_READ_UTF8(z, c);
    t = i;
    if( i>=0xD800 && i<=0xDFFF ) t = 0xFFFD;
    if( (i&0xFFFFFFFE)==0xFFFE ) t = 0xFFFD;
    assert( c==t );
    assert( (z-zBuf)==n );
  }
  for(i=0; i<0x00110000; i++){
    if( i>=0xD800 && i<=0xE000 ) continue;
    z = zBuf;
    WRITE_UTF16LE(z, i);
    n = z-zBuf;
    z[0] = 0;
    z = zBuf;
    READ_UTF16LE(z, c);
    assert( c==i );
    assert( (z-zBuf)==n );
  }
  for(i=0; i<0x00110000; i++){
    if( i>=0xD800 && i<=0xE000 ) continue;
    z = zBuf;
    WRITE_UTF16BE(z, i);
    n = z-zBuf;
    z[0] = 0;
    z = zBuf;
    READ_UTF16BE(z, c);
    assert( c==i );
    assert( (z-zBuf)==n );
  }
}
#endif /* SQLITE_TEST */
#endif /* SQLITE_OMIT_UTF16 */