SQLite

      nHaystack--;
      zHaystack++;
    }while( isText && (zHaystack[0]&0xc0)==0x80 );
  }
  if( nNeedle>nHaystack ) N = 0;
  sqlite3_result_int(context, N);
}

/*
** Implementation of the printf() function.
*/
static void printfFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  PrintfArguments x;
  StrAccum str;
  const char *zFormat;
  int n;

  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, 0, 0, SQLITE_MAX_LENGTH);
    str.db = sqlite3_context_db_handle(context);
    sqlite3XPrintf(&str, SQLITE_PRINTF_SQLFUNC, 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.

    FUNCTION(max,                0, 1, 1, 0                ),
    AGGREGATE(max,               1, 1, 1, minmaxStep,      minMaxFinalize ),
    FUNCTION2(typeof,            1, 0, 0, typeofFunc,  SQLITE_FUNC_TYPEOF),
    FUNCTION2(length,            1, 0, 0, lengthFunc,  SQLITE_FUNC_LENGTH),
    FUNCTION(instr,              2, 0, 0, instrFunc        ),
    FUNCTION(substr,             2, 0, 0, substrFunc       ),
    FUNCTION(substr,             3, 0, 0, substrFunc       ),
    FUNCTION(printf,            -1, 0, 0, printfFunc       ),
    FUNCTION(unicode,            1, 0, 0, unicodeFunc      ),
    FUNCTION(char,              -1, 0, 0, charFunc         ),
    FUNCTION(abs,                1, 0, 0, absFunc          ),
#ifndef SQLITE_OMIT_FLOATING_POINT
    FUNCTION(round,              1, 0, 0, roundFunc        ),
    FUNCTION(round,              2, 0, 0, roundFunc        ),
#endif

    sqlite3StrAccumAppend(pAccum, zSpaces, N);
  }
}

/*
** Set the StrAccum object to an error mode.
*/
static void setStrAccumError(StrAccum *p, u8 eError){
  p->accError = eError;
  p->nAlloc = 0;
}

/*
** Extra argument values from a PrintfArguments object
*/
static sqlite3_int64 getIntArg(PrintfArguments *p){
  if( p->nArg<=p->nUsed ) return 0;
  return sqlite3_value_int64(p->apArg[p->nUsed++]);
}
static double getDoubleArg(PrintfArguments *p){
  if( p->nArg<=p->nUsed ) return 0.0;
  return sqlite3_value_double(p->apArg[p->nUsed++]);
}
static char *getTextArg(PrintfArguments *p){
  if( p->nArg<=p->nUsed ) return 0;
  return (char*)sqlite3_value_text(p->apArg[p->nUsed++]);
}


/*
** On machines with a small stack size, you can redefine the
** SQLITE_PRINT_BUF_SIZE to be something smaller, if desired.
*/
#ifndef SQLITE_PRINT_BUF_SIZE
# define SQLITE_PRINT_BUF_SIZE 70
#endif
#define etBUFSIZE SQLITE_PRINT_BUF_SIZE  /* Size of the output buffer */

/*
** Render a string given by "fmt" into the StrAccum object.
*/
void sqlite3VXPrintf(
  StrAccum *pAccum,          /* Accumulate results here */
  u32 bFlags,                /* SQLITE_PRINTF_* flags */
  const char *fmt,           /* Format string */
  va_list ap                 /* arguments */
){
  int c;                     /* Next character in the format string */
  char *bufpt;               /* Pointer to the conversion buffer */
  int precision;             /* Precision of the current field */
  int length;                /* Length of the field */
  int idx;                   /* A general purpose loop counter */
  int width;                 /* Width of the current field */
  etByte flag_leftjustify;   /* True if "-" flag is present */
  etByte flag_plussign;      /* True if "+" flag is present */
  etByte flag_blanksign;     /* True if " " flag is present */
  etByte flag_alternateform; /* True if "#" flag is present */
  etByte flag_altform2;      /* True if "!" flag is present */
  etByte flag_zeropad;       /* True if field width constant starts with zero */
  etByte flag_long;          /* True if "l" flag is present */
  etByte flag_longlong;      /* True if the "ll" flag is present */
  etByte done;               /* Loop termination flag */
  etByte xtype = 0;          /* Conversion paradigm */
  u8 bArgList;               /* True for SQLITE_PRINTF_SQLFUNC */
  u8 useIntern;              /* Ok to use internal conversions (ex: %T) */
  char prefix;               /* Prefix character.  "+" or "-" or " " or '\0'. */
  sqlite_uint64 longvalue;   /* Value for integer types */
  LONGDOUBLE_TYPE realvalue; /* Value for real types */
  const et_info *infop;      /* Pointer to the appropriate info structure */
  char *zOut;                /* Rendering buffer */
  int nOut;                  /* Size of the rendering buffer */
  char *zExtra;              /* Malloced memory used by some conversion */
#ifndef SQLITE_OMIT_FLOATING_POINT
  int  exp, e2;              /* exponent of real numbers */
  int nsd;                   /* Number of significant digits returned */
  double rounder;            /* Used for rounding floating point values */
  etByte flag_dp;            /* True if decimal point should be shown */
  etByte flag_rtz;           /* True if trailing zeros should be removed */
#endif
  PrintfArguments *pArgList = 0; /* Arguments for SQLITE_PRINTF_SQLFUNC */
  char buf[etBUFSIZE];       /* Conversion buffer */

  bufpt = 0;
  if( bFlags ){
    if( (bArgList = (bFlags & SQLITE_PRINTF_SQLFUNC))!=0 ){
      pArgList = va_arg(ap, PrintfArguments*);
    }
    useIntern = bFlags & SQLITE_PRINTF_INTERNAL;
  }else{
    bArgList = useIntern = 0;
  }
  for(; (c=(*fmt))!=0; ++fmt){
    if( c!='%' ){
      int amt;
      bufpt = (char *)fmt;
      amt = 1;
      while( (c=(*++fmt))!='%' && c!=0 ) amt++;
      sqlite3StrAccumAppend(pAccum, bufpt, amt);

        case '0':   flag_zeropad = 1;         break;
        default:    done = 1;                 break;
      }
    }while( !done && (c=(*++fmt))!=0 );
    /* Get the field width */
    width = 0;
    if( c=='*' ){
      if( bArgList ){
        width = (int)getIntArg(pArgList);
      }else{
        width = va_arg(ap,int);
      }
      if( width<0 ){
        flag_leftjustify = 1;
        width = -width;
      }
      c = *++fmt;
    }else{
      while( c>='0' && c<='9' ){
        width = width*10 + c - '0';
        c = *++fmt;
      }
    }
    /* Get the precision */
    if( c=='.' ){
      precision = 0;
      c = *++fmt;
      if( c=='*' ){
        if( bArgList ){
          precision = (int)getIntArg(pArgList);
        }else{
          precision = va_arg(ap,int);
        }
        if( precision<0 ) precision = -precision;
        c = *++fmt;
      }else{
        while( c>='0' && c<='9' ){
          precision = precision*10 + c - '0';
          c = *++fmt;
        }

    }
    /* Fetch the info entry for the field */
    infop = &fmtinfo[0];
    xtype = etINVALID;
    for(idx=0; idx<ArraySize(fmtinfo); idx++){
      if( c==fmtinfo[idx].fmttype ){
        infop = &fmtinfo[idx];
        if( useIntern || (infop->flags & FLAG_INTERN)==0 ){
          xtype = infop->type;
        }else{
          return;
        }
        break;
      }
    }

        flag_longlong = sizeof(char*)==sizeof(i64);
        flag_long = sizeof(char*)==sizeof(long int);
        /* Fall through into the next case */
      case etORDINAL:
      case etRADIX:
        if( infop->flags & FLAG_SIGNED ){
          i64 v;
          if( bArgList ){
            v = getIntArg(pArgList);
          }else if( flag_longlong ){
            v = va_arg(ap,i64);
          }else if( flag_long ){
            v = va_arg(ap,long int);
          }else{
            v = va_arg(ap,int);
          }
          if( v<0 ){
            if( v==SMALLEST_INT64 ){
              longvalue = ((u64)1)<<63;
            }else{
              longvalue = -v;
            }
            prefix = '-';
          }else{
            longvalue = v;
            if( flag_plussign )        prefix = '+';
            else if( flag_blanksign )  prefix = ' ';
            else                       prefix = 0;
          }
        }else{
          if( bArgList ){
            longvalue = (u64)getIntArg(pArgList);
          }else if( flag_longlong ){
            longvalue = va_arg(ap,u64);
          }else if( flag_long ){
            longvalue = va_arg(ap,unsigned long int);
          }else{
            longvalue = va_arg(ap,unsigned int);
          }
          prefix = 0;

          for(; (x=(*pre))!=0; pre++) *(--bufpt) = x;
        }
        length = (int)(&zOut[nOut-1]-bufpt);
        break;
      case etFLOAT:
      case etEXP:
      case etGENERIC:
        if( bArgList ){
          realvalue = getDoubleArg(pArgList);
        }else{
          realvalue = va_arg(ap,double);
        }
#ifdef SQLITE_OMIT_FLOATING_POINT
        length = 0;
#else
        if( precision<0 ) precision = 6;         /* Set default precision */
        if( realvalue<0.0 ){
          realvalue = -realvalue;
          prefix = '-';

          i = prefix!=0;
          while( nPad-- ) bufpt[i++] = '0';
          length = width;
        }
#endif /* !defined(SQLITE_OMIT_FLOATING_POINT) */
        break;
      case etSIZE:
        if( !bArgList ){
          *(va_arg(ap,int*)) = pAccum->nChar;
        }
        length = width = 0;
        break;
      case etPERCENT:
        buf[0] = '%';
        bufpt = buf;
        length = 1;
        break;
      case etCHARX:
        if( bArgList ){
          bufpt = getTextArg(pArgList);
          c = bufpt ? bufpt[0] : 0;
        }else{
          c = va_arg(ap,int);
        }
        buf[0] = (char)c;
        if( precision>=0 ){
          for(idx=1; idx<precision; idx++) buf[idx] = (char)c;
          length = precision;
        }else{
          length =1;
        }
        bufpt = buf;
        break;
      case etSTRING:
      case etDYNSTRING:
        if( bArgList ){
          bufpt = getTextArg(pArgList);
        }else{
          bufpt = va_arg(ap,char*);
        }
        if( bufpt==0 ){
          bufpt = "";
        }else if( xtype==etDYNSTRING && !bArgList ){
          zExtra = bufpt;
        }
        if( precision>=0 ){
          for(length=0; length<precision && bufpt[length]; length++){}
        }else{
          length = sqlite3Strlen30(bufpt);
        }
        break;
      case etSQLESCAPE:
      case etSQLESCAPE2:
      case etSQLESCAPE3: {
        int i, j, k, n, isnull;
        int needQuote;
        char ch;
        char q = ((xtype==etSQLESCAPE3)?'"':'\'');   /* Quote character */
        char *escarg;

        if( bArgList ){
          escarg = getTextArg(pArgList);
        }else{
          escarg = va_arg(ap,char*);
        }
        isnull = escarg==0;
        if( isnull ) escarg = (xtype==etSQLESCAPE2 ? "NULL" : "(NULL)");
        k = precision;
        for(i=n=0; k!=0 && (ch=escarg[i])!=0; i++, k--){
          if( ch==q )  n++;
        }
        needQuote = !isnull && xtype==etSQLESCAPE2;

        /* The precision in %q and %Q means how many input characters to
        ** consume, not the length of the output...
        ** if( precision>=0 && precision<length ) length = precision; */
        break;
      }
      case etTOKEN: {
        Token *pToken = va_arg(ap, Token*);
        assert( bArgList==0 );
        if( pToken && pToken->n ){
          sqlite3StrAccumAppend(pAccum, (const char*)pToken->z, pToken->n);
        }
        length = width = 0;
        break;
      }
      case etSRCLIST: {
        SrcList *pSrc = va_arg(ap, SrcList*);
        int k = va_arg(ap, int);
        struct SrcList_item *pItem = &pSrc->a[k];
        assert( bArgList==0 );
        assert( k>=0 && k<pSrc->nSrc );
        if( pItem->zDatabase ){
          sqlite3StrAccumAppendAll(pAccum, pItem->zDatabase);
          sqlite3StrAccumAppend(pAccum, ".", 1);
        }
        sqlite3StrAccumAppendAll(pAccum, pItem->zName);
        length = width = 0;

  char *z;
  char zBase[SQLITE_PRINT_BUF_SIZE];
  StrAccum acc;
  assert( db!=0 );
  sqlite3StrAccumInit(&acc, zBase, sizeof(zBase),
                      db->aLimit[SQLITE_LIMIT_LENGTH]);
  acc.db = db;
  sqlite3VXPrintf(&acc, SQLITE_PRINTF_INTERNAL, zFormat, ap);
  z = sqlite3StrAccumFinish(&acc);
  if( acc.accError==STRACCUM_NOMEM ){
    db->mallocFailed = 1;
  }
  return z;
}

  va_end(ap);
  sqlite3StrAccumFinish(&acc);
  fprintf(stdout,"%s", zBuf);
  fflush(stdout);
}
#endif


/*
** variable-argument wrapper around sqlite3VXPrintf().
*/
void sqlite3XPrintf(StrAccum *p, u32 bFlags, const char *zFormat, ...){
  va_list ap;
  va_start(ap,zFormat);
  sqlite3VXPrintf(p, bFlags, zFormat, ap);
  va_end(ap);
}

typedef struct KeyClass KeyClass;
typedef struct KeyInfo KeyInfo;
typedef struct Lookaside Lookaside;
typedef struct LookasideSlot LookasideSlot;
typedef struct Module Module;
typedef struct NameContext NameContext;
typedef struct Parse Parse;
typedef struct PrintfArguments PrintfArguments;
typedef struct RowSet RowSet;
typedef struct Savepoint Savepoint;
typedef struct Select Select;
typedef struct SelectDest SelectDest;
typedef struct SrcList SrcList;
typedef struct StrAccum StrAccum;
typedef struct Table Table;

#ifndef SQLITE_OMIT_FLOATING_POINT
  int sqlite3IsNaN(double);
#else
# define sqlite3IsNaN(X)  0
#endif

/*
** An instance of the following structure holds information about SQL
** functions arguments that are the parameters to the printf() function.
*/
struct PrintfArguments {
  int nArg;                /* Total number of arguments */
  int nUsed;               /* Number of arguments used so far */
  sqlite3_value **apArg;   /* The argument values */
};

#define SQLITE_PRINTF_INTERNAL 0x01
#define SQLITE_PRINTF_SQLFUNC  0x02
void sqlite3VXPrintf(StrAccum*, u32, const char*, va_list);

void sqlite3XPrintf(StrAccum*, u32, const char*, ...);

char *sqlite3MPrintf(sqlite3*,const char*, ...);
char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
char *sqlite3MAppendf(sqlite3*,char*,const char*,...);
#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
  void sqlite3DebugPrintf(const char*, ...);
#endif
#if defined(SQLITE_TEST)

      zRawSql += nToken;
      nextIndex = idx + 1;
      assert( idx>0 && idx<=p->nVar );
      pVar = &p->aVar[idx-1];
      if( pVar->flags & MEM_Null ){
        sqlite3StrAccumAppend(&out, "NULL", 4);
      }else if( pVar->flags & MEM_Int ){
        sqlite3XPrintf(&out, 0, "%lld", pVar->u.i);
      }else if( pVar->flags & MEM_Real ){
        sqlite3XPrintf(&out, 0, "%!.15g", pVar->r);
      }else if( pVar->flags & MEM_Str ){
        int nOut;  /* Number of bytes of the string text to include in output */
#ifndef SQLITE_OMIT_UTF16
        u8 enc = ENC(db);
        Mem utf8;
        if( enc!=SQLITE_UTF8 ){
          memset(&utf8, 0, sizeof(utf8));
          utf8.db = db;
          sqlite3VdbeMemSetStr(&utf8, pVar->z, pVar->n, enc, SQLITE_STATIC);
          sqlite3VdbeChangeEncoding(&utf8, SQLITE_UTF8);
          pVar = &utf8;
        }
#endif
        nOut = pVar->n;
#ifdef SQLITE_TRACE_SIZE_LIMIT
        if( nOut>SQLITE_TRACE_SIZE_LIMIT ){
          nOut = SQLITE_TRACE_SIZE_LIMIT;
          while( nOut<pVar->n && (pVar->z[nOut]&0xc0)==0x80 ){ nOut++; }
        }
#endif    
        sqlite3XPrintf(&out, 0, "'%.*q'", nOut, pVar->z);
#ifdef SQLITE_TRACE_SIZE_LIMIT
        if( nOut<pVar->n ){
          sqlite3XPrintf(&out, 0, "/*+%d bytes*/", pVar->n-nOut);
        }
#endif
#ifndef SQLITE_OMIT_UTF16
        if( enc!=SQLITE_UTF8 ) sqlite3VdbeMemRelease(&utf8);
#endif
      }else if( pVar->flags & MEM_Zero ){
        sqlite3XPrintf(&out, 0, "zeroblob(%d)", pVar->u.nZero);
      }else{
        int nOut;  /* Number of bytes of the blob to include in output */
        assert( pVar->flags & MEM_Blob );
        sqlite3StrAccumAppend(&out, "x'", 2);
        nOut = pVar->n;
#ifdef SQLITE_TRACE_SIZE_LIMIT
        if( nOut>SQLITE_TRACE_SIZE_LIMIT ) nOut = SQLITE_TRACE_SIZE_LIMIT;
#endif
        for(i=0; i<nOut; i++){
          sqlite3XPrintf(&out, 0, "%02x", pVar->z[i]&0xff);
        }
        sqlite3StrAccumAppend(&out, "'", 1);
#ifdef SQLITE_TRACE_SIZE_LIMIT
        if( nOut<pVar->n ){
          sqlite3XPrintf(&out, 0, "/*+%d bytes*/", pVar->n-nOut);
        }
#endif
      }
    }
  }
  return sqlite3StrAccumFinish(&out);
}

    va_list ap;
    if( p->nIndent && endsWithNL(p) ){
      int n = p->nIndent;
      if( n>ArraySize(p->aIndent) ) n = ArraySize(p->aIndent);
      sqlite3AppendSpace(&p->str, p->aIndent[n-1]);
    }   
    va_start(ap, zFormat);
    sqlite3VXPrintf(&p->str, SQLITE_PRINTF_INTERNAL, zFormat, ap);
    va_end(ap);
  }
}

/*
** Append a '\n' if there is not already one.
*/

# 2013-12-17
#
# 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 implements regression tests for SQLite library.  The
# focus of this file is testing the printf() SQL function.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

do_execsql_test printf2-1.1 {
  SELECT printf();
} {{}}
do_execsql_test printf2-1.2 {
  SELECT printf('hello');
} {hello}
do_execsql_test printf2-1.3 {
  SELECT printf('%d,%d,%d',55,-11,3421);
} {55,-11,3421}
do_execsql_test printf2-1.4 {
  SELECT printf('%d,%d,%d',55,'-11',3421);
} {55,-11,3421}
do_execsql_test printf2-1.5 {
  SELECT printf('%d,%d,%d,%d',55,'-11',3421);
} {55,-11,3421,0}
do_execsql_test printf2-1.6 {
  SELECT printf('%.2f',3.141592653);
} {3.14}
do_execsql_test printf2-1.7 {
  SELECT printf('%.*f',2,3.141592653);
} {3.14}
do_execsql_test printf2-1.8 {
  SELECT printf('%*.*f',5,2,3.141592653);
} {{ 3.14}}
do_execsql_test printf2-1.9 {
  SELECT printf('%d',314159.2653);
} {314159}
do_execsql_test printf2-1.10 {
  SELECT printf('%lld',314159.2653);
} {314159}
do_execsql_test printf2-1.11 {
  SELECT printf('%lld%n',314159.2653,'hi');
} {314159}
do_execsql_test printf2-1.12 {
  SELECT printf('%.*z',5,'abcdefghijklmnop');
} {abcde}
do_execsql_test printf2-1.13 {
  SELECT printf('%c','abcdefghijklmnop');
} {a}


finish_test