persistentstorage/sql/SQLite/printf.c
changeset 0 08ec8eefde2f
child 23 26645d81f48d
equal deleted inserted replaced
-1:000000000000 0:08ec8eefde2f
       
     1 /*
       
     2 ** The "printf" code that follows dates from the 1980's.  It is in
       
     3 ** the public domain.  The original comments are included here for
       
     4 ** completeness.  They are very out-of-date but might be useful as
       
     5 ** an historical reference.  Most of the "enhancements" have been backed
       
     6 ** out so that the functionality is now the same as standard printf().
       
     7 **
       
     8 ** $Id: printf.c,v 1.93 2008/07/28 19:34:53 drh Exp $
       
     9 **
       
    10 **************************************************************************
       
    11 **
       
    12 ** The following modules is an enhanced replacement for the "printf" subroutines
       
    13 ** found in the standard C library.  The following enhancements are
       
    14 ** supported:
       
    15 **
       
    16 **      +  Additional functions.  The standard set of "printf" functions
       
    17 **         includes printf, fprintf, sprintf, vprintf, vfprintf, and
       
    18 **         vsprintf.  This module adds the following:
       
    19 **
       
    20 **           *  snprintf -- Works like sprintf, but has an extra argument
       
    21 **                          which is the size of the buffer written to.
       
    22 **
       
    23 **           *  mprintf --  Similar to sprintf.  Writes output to memory
       
    24 **                          obtained from malloc.
       
    25 **
       
    26 **           *  xprintf --  Calls a function to dispose of output.
       
    27 **
       
    28 **           *  nprintf --  No output, but returns the number of characters
       
    29 **                          that would have been output by printf.
       
    30 **
       
    31 **           *  A v- version (ex: vsnprintf) of every function is also
       
    32 **              supplied.
       
    33 **
       
    34 **      +  A few extensions to the formatting notation are supported:
       
    35 **
       
    36 **           *  The "=" flag (similar to "-") causes the output to be
       
    37 **              be centered in the appropriately sized field.
       
    38 **
       
    39 **           *  The %b field outputs an integer in binary notation.
       
    40 **
       
    41 **           *  The %c field now accepts a precision.  The character output
       
    42 **              is repeated by the number of times the precision specifies.
       
    43 **
       
    44 **           *  The %' field works like %c, but takes as its character the
       
    45 **              next character of the format string, instead of the next
       
    46 **              argument.  For example,  printf("%.78'-")  prints 78 minus
       
    47 **              signs, the same as  printf("%.78c",'-').
       
    48 **
       
    49 **      +  When compiled using GCC on a SPARC, this version of printf is
       
    50 **         faster than the library printf for SUN OS 4.1.
       
    51 **
       
    52 **      +  All functions are fully reentrant.
       
    53 **
       
    54 */
       
    55 #include "sqliteInt.h"
       
    56 
       
    57 /*
       
    58 ** Conversion types fall into various categories as defined by the
       
    59 ** following enumeration.
       
    60 */
       
    61 #define etRADIX       1 /* Integer types.  %d, %x, %o, and so forth */
       
    62 #define etFLOAT       2 /* Floating point.  %f */
       
    63 #define etEXP         3 /* Exponentional notation. %e and %E */
       
    64 #define etGENERIC     4 /* Floating or exponential, depending on exponent. %g */
       
    65 #define etSIZE        5 /* Return number of characters processed so far. %n */
       
    66 #define etSTRING      6 /* Strings. %s */
       
    67 #define etDYNSTRING   7 /* Dynamically allocated strings. %z */
       
    68 #define etPERCENT     8 /* Percent symbol. %% */
       
    69 #define etCHARX       9 /* Characters. %c */
       
    70 /* The rest are extensions, not normally found in printf() */
       
    71 #define etSQLESCAPE  10 /* Strings with '\'' doubled.  %q */
       
    72 #define etSQLESCAPE2 11 /* Strings with '\'' doubled and enclosed in '',
       
    73                           NULL pointers replaced by SQL NULL.  %Q */
       
    74 #define etTOKEN      12 /* a pointer to a Token structure */
       
    75 #define etSRCLIST    13 /* a pointer to a SrcList */
       
    76 #define etPOINTER    14 /* The %p conversion */
       
    77 #define etSQLESCAPE3 15 /* %w -> Strings with '\"' doubled */
       
    78 #define etORDINAL    16 /* %r -> 1st, 2nd, 3rd, 4th, etc.  English only */
       
    79 
       
    80 
       
    81 /*
       
    82 ** An "etByte" is an 8-bit unsigned value.
       
    83 */
       
    84 typedef unsigned char etByte;
       
    85 
       
    86 /*
       
    87 ** Each builtin conversion character (ex: the 'd' in "%d") is described
       
    88 ** by an instance of the following structure
       
    89 */
       
    90 typedef struct et_info {   /* Information about each format field */
       
    91   char fmttype;            /* The format field code letter */
       
    92   etByte base;             /* The base for radix conversion */
       
    93   etByte flags;            /* One or more of FLAG_ constants below */
       
    94   etByte type;             /* Conversion paradigm */
       
    95   etByte charset;          /* Offset into aDigits[] of the digits string */
       
    96   etByte prefix;           /* Offset into aPrefix[] of the prefix string */
       
    97 } et_info;
       
    98 
       
    99 /*
       
   100 ** Allowed values for et_info.flags
       
   101 */
       
   102 #define FLAG_SIGNED  1     /* True if the value to convert is signed */
       
   103 #define FLAG_INTERN  2     /* True if for internal use only */
       
   104 #define FLAG_STRING  4     /* Allow infinity precision */
       
   105 
       
   106 
       
   107 /*
       
   108 ** The following table is searched linearly, so it is good to put the
       
   109 ** most frequently used conversion types first.
       
   110 */
       
   111 static const char aDigits[] = "0123456789ABCDEF0123456789abcdef";
       
   112 static const char aPrefix[] = "-x0\000X0";
       
   113 static const et_info fmtinfo[] = {
       
   114   {  'd', 10, 1, etRADIX,      0,  0 },
       
   115   {  's',  0, 4, etSTRING,     0,  0 },
       
   116   {  'g',  0, 1, etGENERIC,    30, 0 },
       
   117   {  'z',  0, 4, etDYNSTRING,  0,  0 },
       
   118   {  'q',  0, 4, etSQLESCAPE,  0,  0 },
       
   119   {  'Q',  0, 4, etSQLESCAPE2, 0,  0 },
       
   120   {  'w',  0, 4, etSQLESCAPE3, 0,  0 },
       
   121   {  'c',  0, 0, etCHARX,      0,  0 },
       
   122   {  'o',  8, 0, etRADIX,      0,  2 },
       
   123   {  'u', 10, 0, etRADIX,      0,  0 },
       
   124   {  'x', 16, 0, etRADIX,      16, 1 },
       
   125   {  'X', 16, 0, etRADIX,      0,  4 },
       
   126 #ifndef SQLITE_OMIT_FLOATING_POINT
       
   127   {  'f',  0, 1, etFLOAT,      0,  0 },
       
   128   {  'e',  0, 1, etEXP,        30, 0 },
       
   129   {  'E',  0, 1, etEXP,        14, 0 },
       
   130   {  'G',  0, 1, etGENERIC,    14, 0 },
       
   131 #endif
       
   132   {  'i', 10, 1, etRADIX,      0,  0 },
       
   133   {  'n',  0, 0, etSIZE,       0,  0 },
       
   134   {  '%',  0, 0, etPERCENT,    0,  0 },
       
   135   {  'p', 16, 0, etPOINTER,    0,  1 },
       
   136   {  'T',  0, 2, etTOKEN,      0,  0 },
       
   137   {  'S',  0, 2, etSRCLIST,    0,  0 },
       
   138   {  'r', 10, 3, etORDINAL,    0,  0 },
       
   139 };
       
   140 #define etNINFO  (sizeof(fmtinfo)/sizeof(fmtinfo[0]))
       
   141 
       
   142 /*
       
   143 ** If SQLITE_OMIT_FLOATING_POINT is defined, then none of the floating point
       
   144 ** conversions will work.
       
   145 */
       
   146 #ifndef SQLITE_OMIT_FLOATING_POINT
       
   147 /*
       
   148 ** "*val" is a double such that 0.1 <= *val < 10.0
       
   149 ** Return the ascii code for the leading digit of *val, then
       
   150 ** multiply "*val" by 10.0 to renormalize.
       
   151 **
       
   152 ** Example:
       
   153 **     input:     *val = 3.14159
       
   154 **     output:    *val = 1.4159    function return = '3'
       
   155 **
       
   156 ** The counter *cnt is incremented each time.  After counter exceeds
       
   157 ** 16 (the number of significant digits in a 64-bit float) '0' is
       
   158 ** always returned.
       
   159 */
       
   160 static int et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
       
   161   int digit;
       
   162   LONGDOUBLE_TYPE d;
       
   163   if( (*cnt)++ >= 16 ) return '0';
       
   164   digit = (int)*val;
       
   165   d = digit;
       
   166   digit += '0';
       
   167   *val = (*val - d)*10.0;
       
   168   return digit;
       
   169 }
       
   170 #endif /* SQLITE_OMIT_FLOATING_POINT */
       
   171 
       
   172 /*
       
   173 ** Append N space characters to the given string buffer.
       
   174 */
       
   175 static void appendSpace(StrAccum *pAccum, int N){
       
   176   static const char zSpaces[] = "                             ";
       
   177   while( N>=sizeof(zSpaces)-1 ){
       
   178     sqlite3StrAccumAppend(pAccum, zSpaces, sizeof(zSpaces)-1);
       
   179     N -= sizeof(zSpaces)-1;
       
   180   }
       
   181   if( N>0 ){
       
   182     sqlite3StrAccumAppend(pAccum, zSpaces, N);
       
   183   }
       
   184 }
       
   185 
       
   186 /*
       
   187 ** On machines with a small stack size, you can redefine the
       
   188 ** SQLITE_PRINT_BUF_SIZE to be less than 350.  But beware - for
       
   189 ** smaller values some %f conversions may go into an infinite loop.
       
   190 */
       
   191 #ifndef SQLITE_PRINT_BUF_SIZE
       
   192 # define SQLITE_PRINT_BUF_SIZE 350
       
   193 #endif
       
   194 #define etBUFSIZE SQLITE_PRINT_BUF_SIZE  /* Size of the output buffer */
       
   195 
       
   196 /*
       
   197 ** The root program.  All variations call this core.
       
   198 **
       
   199 ** INPUTS:
       
   200 **   func   This is a pointer to a function taking three arguments
       
   201 **            1. A pointer to anything.  Same as the "arg" parameter.
       
   202 **            2. A pointer to the list of characters to be output
       
   203 **               (Note, this list is NOT null terminated.)
       
   204 **            3. An integer number of characters to be output.
       
   205 **               (Note: This number might be zero.)
       
   206 **
       
   207 **   arg    This is the pointer to anything which will be passed as the
       
   208 **          first argument to "func".  Use it for whatever you like.
       
   209 **
       
   210 **   fmt    This is the format string, as in the usual print.
       
   211 **
       
   212 **   ap     This is a pointer to a list of arguments.  Same as in
       
   213 **          vfprint.
       
   214 **
       
   215 ** OUTPUTS:
       
   216 **          The return value is the total number of characters sent to
       
   217 **          the function "func".  Returns -1 on a error.
       
   218 **
       
   219 ** Note that the order in which automatic variables are declared below
       
   220 ** seems to make a big difference in determining how fast this beast
       
   221 ** will run.
       
   222 */
       
   223 void sqlite3VXPrintf(
       
   224   StrAccum *pAccum,                  /* Accumulate results here */
       
   225   int useExtended,                   /* Allow extended %-conversions */
       
   226   const char *fmt,                   /* Format string */
       
   227   va_list ap                         /* arguments */
       
   228 ){
       
   229   int c;                     /* Next character in the format string */
       
   230   char *bufpt;               /* Pointer to the conversion buffer */
       
   231   int precision;             /* Precision of the current field */
       
   232   int length;                /* Length of the field */
       
   233   int idx;                   /* A general purpose loop counter */
       
   234   int width;                 /* Width of the current field */
       
   235   etByte flag_leftjustify;   /* True if "-" flag is present */
       
   236   etByte flag_plussign;      /* True if "+" flag is present */
       
   237   etByte flag_blanksign;     /* True if " " flag is present */
       
   238   etByte flag_alternateform; /* True if "#" flag is present */
       
   239   etByte flag_altform2;      /* True if "!" flag is present */
       
   240   etByte flag_zeropad;       /* True if field width constant starts with zero */
       
   241   etByte flag_long;          /* True if "l" flag is present */
       
   242   etByte flag_longlong;      /* True if the "ll" flag is present */
       
   243   etByte done;               /* Loop termination flag */
       
   244   sqlite_uint64 longvalue;   /* Value for integer types */
       
   245   LONGDOUBLE_TYPE realvalue; /* Value for real types */
       
   246   const et_info *infop;      /* Pointer to the appropriate info structure */
       
   247   char buf[etBUFSIZE];       /* Conversion buffer */
       
   248   char prefix;               /* Prefix character.  "+" or "-" or " " or '\0'. */
       
   249   etByte errorflag = 0;      /* True if an error is encountered */
       
   250   etByte xtype;              /* Conversion paradigm */
       
   251   char *zExtra;              /* Extra memory used for etTCLESCAPE conversions */
       
   252 #ifndef SQLITE_OMIT_FLOATING_POINT
       
   253   int  exp, e2;              /* exponent of real numbers */
       
   254   double rounder;            /* Used for rounding floating point values */
       
   255   etByte flag_dp;            /* True if decimal point should be shown */
       
   256   etByte flag_rtz;           /* True if trailing zeros should be removed */
       
   257   etByte flag_exp;           /* True to force display of the exponent */
       
   258   int nsd;                   /* Number of significant digits returned */
       
   259 #endif
       
   260 
       
   261   length = 0;
       
   262   bufpt = 0;
       
   263   for(; (c=(*fmt))!=0; ++fmt){
       
   264     if( c!='%' ){
       
   265       int amt;
       
   266       bufpt = (char *)fmt;
       
   267       amt = 1;
       
   268       while( (c=(*++fmt))!='%' && c!=0 ) amt++;
       
   269       sqlite3StrAccumAppend(pAccum, bufpt, amt);
       
   270       if( c==0 ) break;
       
   271     }
       
   272     if( (c=(*++fmt))==0 ){
       
   273       errorflag = 1;
       
   274       sqlite3StrAccumAppend(pAccum, "%", 1);
       
   275       break;
       
   276     }
       
   277     /* Find out what flags are present */
       
   278     flag_leftjustify = flag_plussign = flag_blanksign = 
       
   279      flag_alternateform = flag_altform2 = flag_zeropad = 0;
       
   280     done = 0;
       
   281     do{
       
   282       switch( c ){
       
   283         case '-':   flag_leftjustify = 1;     break;
       
   284         case '+':   flag_plussign = 1;        break;
       
   285         case ' ':   flag_blanksign = 1;       break;
       
   286         case '#':   flag_alternateform = 1;   break;
       
   287         case '!':   flag_altform2 = 1;        break;
       
   288         case '0':   flag_zeropad = 1;         break;
       
   289         default:    done = 1;                 break;
       
   290       }
       
   291     }while( !done && (c=(*++fmt))!=0 );
       
   292     /* Get the field width */
       
   293     width = 0;
       
   294     if( c=='*' ){
       
   295       width = va_arg(ap,int);
       
   296       if( width<0 ){
       
   297         flag_leftjustify = 1;
       
   298         width = -width;
       
   299       }
       
   300       c = *++fmt;
       
   301     }else{
       
   302       while( c>='0' && c<='9' ){
       
   303         width = width*10 + c - '0';
       
   304         c = *++fmt;
       
   305       }
       
   306     }
       
   307     if( width > etBUFSIZE-10 ){
       
   308       width = etBUFSIZE-10;
       
   309     }
       
   310     /* Get the precision */
       
   311     if( c=='.' ){
       
   312       precision = 0;
       
   313       c = *++fmt;
       
   314       if( c=='*' ){
       
   315         precision = va_arg(ap,int);
       
   316         if( precision<0 ) precision = -precision;
       
   317         c = *++fmt;
       
   318       }else{
       
   319         while( c>='0' && c<='9' ){
       
   320           precision = precision*10 + c - '0';
       
   321           c = *++fmt;
       
   322         }
       
   323       }
       
   324     }else{
       
   325       precision = -1;
       
   326     }
       
   327     /* Get the conversion type modifier */
       
   328     if( c=='l' ){
       
   329       flag_long = 1;
       
   330       c = *++fmt;
       
   331       if( c=='l' ){
       
   332         flag_longlong = 1;
       
   333         c = *++fmt;
       
   334       }else{
       
   335         flag_longlong = 0;
       
   336       }
       
   337     }else{
       
   338       flag_long = flag_longlong = 0;
       
   339     }
       
   340     /* Fetch the info entry for the field */
       
   341     infop = 0;
       
   342     for(idx=0; idx<etNINFO; idx++){
       
   343       if( c==fmtinfo[idx].fmttype ){
       
   344         infop = &fmtinfo[idx];
       
   345         if( useExtended || (infop->flags & FLAG_INTERN)==0 ){
       
   346           xtype = infop->type;
       
   347         }else{
       
   348           return;
       
   349         }
       
   350         break;
       
   351       }
       
   352     }
       
   353     zExtra = 0;
       
   354     if( infop==0 ){
       
   355       return;
       
   356     }
       
   357 
       
   358 
       
   359     /* Limit the precision to prevent overflowing buf[] during conversion */
       
   360     if( precision>etBUFSIZE-40 && (infop->flags & FLAG_STRING)==0 ){
       
   361       precision = etBUFSIZE-40;
       
   362     }
       
   363 
       
   364     /*
       
   365     ** At this point, variables are initialized as follows:
       
   366     **
       
   367     **   flag_alternateform          TRUE if a '#' is present.
       
   368     **   flag_altform2               TRUE if a '!' is present.
       
   369     **   flag_plussign               TRUE if a '+' is present.
       
   370     **   flag_leftjustify            TRUE if a '-' is present or if the
       
   371     **                               field width was negative.
       
   372     **   flag_zeropad                TRUE if the width began with 0.
       
   373     **   flag_long                   TRUE if the letter 'l' (ell) prefixed
       
   374     **                               the conversion character.
       
   375     **   flag_longlong               TRUE if the letter 'll' (ell ell) prefixed
       
   376     **                               the conversion character.
       
   377     **   flag_blanksign              TRUE if a ' ' is present.
       
   378     **   width                       The specified field width.  This is
       
   379     **                               always non-negative.  Zero is the default.
       
   380     **   precision                   The specified precision.  The default
       
   381     **                               is -1.
       
   382     **   xtype                       The class of the conversion.
       
   383     **   infop                       Pointer to the appropriate info struct.
       
   384     */
       
   385     switch( xtype ){
       
   386       case etPOINTER:
       
   387         flag_longlong = sizeof(char*)==sizeof(i64);
       
   388         flag_long = sizeof(char*)==sizeof(long int);
       
   389         /* Fall through into the next case */
       
   390       case etORDINAL:
       
   391       case etRADIX:
       
   392         if( infop->flags & FLAG_SIGNED ){
       
   393           i64 v;
       
   394           if( flag_longlong )   v = va_arg(ap,i64);
       
   395           else if( flag_long )  v = va_arg(ap,long int);
       
   396           else                  v = va_arg(ap,int);
       
   397           if( v<0 ){
       
   398             longvalue = -v;
       
   399             prefix = '-';
       
   400           }else{
       
   401             longvalue = v;
       
   402             if( flag_plussign )        prefix = '+';
       
   403             else if( flag_blanksign )  prefix = ' ';
       
   404             else                       prefix = 0;
       
   405           }
       
   406         }else{
       
   407           if( flag_longlong )   longvalue = va_arg(ap,u64);
       
   408           else if( flag_long )  longvalue = va_arg(ap,unsigned long int);
       
   409           else                  longvalue = va_arg(ap,unsigned int);
       
   410           prefix = 0;
       
   411         }
       
   412         if( longvalue==0 ) flag_alternateform = 0;
       
   413         if( flag_zeropad && precision<width-(prefix!=0) ){
       
   414           precision = width-(prefix!=0);
       
   415         }
       
   416         bufpt = &buf[etBUFSIZE-1];
       
   417         if( xtype==etORDINAL ){
       
   418           static const char zOrd[] = "thstndrd";
       
   419           int x = longvalue % 10;
       
   420           if( x>=4 || (longvalue/10)%10==1 ){
       
   421             x = 0;
       
   422           }
       
   423           buf[etBUFSIZE-3] = zOrd[x*2];
       
   424           buf[etBUFSIZE-2] = zOrd[x*2+1];
       
   425           bufpt -= 2;
       
   426         }
       
   427         {
       
   428           register const char *cset;      /* Use registers for speed */
       
   429           register int base;
       
   430           cset = &aDigits[infop->charset];
       
   431           base = infop->base;
       
   432           do{                                           /* Convert to ascii */
       
   433             *(--bufpt) = cset[longvalue%base];
       
   434             longvalue = longvalue/base;
       
   435           }while( longvalue>0 );
       
   436         }
       
   437         length = &buf[etBUFSIZE-1]-bufpt;
       
   438         for(idx=precision-length; idx>0; idx--){
       
   439           *(--bufpt) = '0';                             /* Zero pad */
       
   440         }
       
   441         if( prefix ) *(--bufpt) = prefix;               /* Add sign */
       
   442         if( flag_alternateform && infop->prefix ){      /* Add "0" or "0x" */
       
   443           const char *pre;
       
   444           char x;
       
   445           pre = &aPrefix[infop->prefix];
       
   446           for(; (x=(*pre))!=0; pre++) *(--bufpt) = x;
       
   447         }
       
   448         length = &buf[etBUFSIZE-1]-bufpt;
       
   449         break;
       
   450       case etFLOAT:
       
   451       case etEXP:
       
   452       case etGENERIC:
       
   453         realvalue = va_arg(ap,double);
       
   454 #ifndef SQLITE_OMIT_FLOATING_POINT
       
   455         if( precision<0 ) precision = 6;         /* Set default precision */
       
   456         if( precision>etBUFSIZE/2-10 ) precision = etBUFSIZE/2-10;
       
   457         if( realvalue<0.0 ){
       
   458           realvalue = -realvalue;
       
   459           prefix = '-';
       
   460         }else{
       
   461           if( flag_plussign )          prefix = '+';
       
   462           else if( flag_blanksign )    prefix = ' ';
       
   463           else                         prefix = 0;
       
   464         }
       
   465         if( xtype==etGENERIC && precision>0 ) precision--;
       
   466 #if 0
       
   467         /* Rounding works like BSD when the constant 0.4999 is used.  Wierd! */
       
   468         for(idx=precision, rounder=0.4999; idx>0; idx--, rounder*=0.1);
       
   469 #else
       
   470         /* It makes more sense to use 0.5 */
       
   471         for(idx=precision, rounder=0.5; idx>0; idx--, rounder*=0.1){}
       
   472 #endif
       
   473         if( xtype==etFLOAT ) realvalue += rounder;
       
   474         /* Normalize realvalue to within 10.0 > realvalue >= 1.0 */
       
   475         exp = 0;
       
   476         if( sqlite3IsNaN(realvalue) ){
       
   477           bufpt = "NaN";
       
   478           length = 3;
       
   479           break;
       
   480         }
       
   481         if( realvalue>0.0 ){
       
   482           while( realvalue>=1e32 && exp<=350 ){ realvalue *= 1e-32; exp+=32; }
       
   483           while( realvalue>=1e8 && exp<=350 ){ realvalue *= 1e-8; exp+=8; }
       
   484           while( realvalue>=10.0 && exp<=350 ){ realvalue *= 0.1; exp++; }
       
   485           while( realvalue<1e-8 ){ realvalue *= 1e8; exp-=8; }
       
   486           while( realvalue<1.0 ){ realvalue *= 10.0; exp--; }
       
   487           if( exp>350 ){
       
   488             if( prefix=='-' ){
       
   489               bufpt = "-Inf";
       
   490             }else if( prefix=='+' ){
       
   491               bufpt = "+Inf";
       
   492             }else{
       
   493               bufpt = "Inf";
       
   494             }
       
   495             length = strlen(bufpt);
       
   496             break;
       
   497           }
       
   498         }
       
   499         bufpt = buf;
       
   500         /*
       
   501         ** If the field type is etGENERIC, then convert to either etEXP
       
   502         ** or etFLOAT, as appropriate.
       
   503         */
       
   504         flag_exp = xtype==etEXP;
       
   505         if( xtype!=etFLOAT ){
       
   506           realvalue += rounder;
       
   507           if( realvalue>=10.0 ){ realvalue *= 0.1; exp++; }
       
   508         }
       
   509         if( xtype==etGENERIC ){
       
   510           flag_rtz = !flag_alternateform;
       
   511           if( exp<-4 || exp>precision ){
       
   512             xtype = etEXP;
       
   513           }else{
       
   514             precision = precision - exp;
       
   515             xtype = etFLOAT;
       
   516           }
       
   517         }else{
       
   518           flag_rtz = 0;
       
   519         }
       
   520         if( xtype==etEXP ){
       
   521           e2 = 0;
       
   522         }else{
       
   523           e2 = exp;
       
   524         }
       
   525         nsd = 0;
       
   526         flag_dp = (precision>0) | flag_alternateform | flag_altform2;
       
   527         /* The sign in front of the number */
       
   528         if( prefix ){
       
   529           *(bufpt++) = prefix;
       
   530         }
       
   531         /* Digits prior to the decimal point */
       
   532         if( e2<0 ){
       
   533           *(bufpt++) = '0';
       
   534         }else{
       
   535           for(; e2>=0; e2--){
       
   536             *(bufpt++) = et_getdigit(&realvalue,&nsd);
       
   537           }
       
   538         }
       
   539         /* The decimal point */
       
   540         if( flag_dp ){
       
   541           *(bufpt++) = '.';
       
   542         }
       
   543         /* "0" digits after the decimal point but before the first
       
   544         ** significant digit of the number */
       
   545         for(e2++; e2<0; precision--, e2++){
       
   546           assert( precision>0 );
       
   547           *(bufpt++) = '0';
       
   548         }
       
   549         /* Significant digits after the decimal point */
       
   550         while( (precision--)>0 ){
       
   551           *(bufpt++) = et_getdigit(&realvalue,&nsd);
       
   552         }
       
   553         /* Remove trailing zeros and the "." if no digits follow the "." */
       
   554         if( flag_rtz && flag_dp ){
       
   555           while( bufpt[-1]=='0' ) *(--bufpt) = 0;
       
   556           assert( bufpt>buf );
       
   557           if( bufpt[-1]=='.' ){
       
   558             if( flag_altform2 ){
       
   559               *(bufpt++) = '0';
       
   560             }else{
       
   561               *(--bufpt) = 0;
       
   562             }
       
   563           }
       
   564         }
       
   565         /* Add the "eNNN" suffix */
       
   566         if( flag_exp || xtype==etEXP ){
       
   567           *(bufpt++) = aDigits[infop->charset];
       
   568           if( exp<0 ){
       
   569             *(bufpt++) = '-'; exp = -exp;
       
   570           }else{
       
   571             *(bufpt++) = '+';
       
   572           }
       
   573           if( exp>=100 ){
       
   574             *(bufpt++) = (exp/100)+'0';                /* 100's digit */
       
   575             exp %= 100;
       
   576           }
       
   577           *(bufpt++) = exp/10+'0';                     /* 10's digit */
       
   578           *(bufpt++) = exp%10+'0';                     /* 1's digit */
       
   579         }
       
   580         *bufpt = 0;
       
   581 
       
   582         /* The converted number is in buf[] and zero terminated. Output it.
       
   583         ** Note that the number is in the usual order, not reversed as with
       
   584         ** integer conversions. */
       
   585         length = bufpt-buf;
       
   586         bufpt = buf;
       
   587 
       
   588         /* Special case:  Add leading zeros if the flag_zeropad flag is
       
   589         ** set and we are not left justified */
       
   590         if( flag_zeropad && !flag_leftjustify && length < width){
       
   591           int i;
       
   592           int nPad = width - length;
       
   593           for(i=width; i>=nPad; i--){
       
   594             bufpt[i] = bufpt[i-nPad];
       
   595           }
       
   596           i = prefix!=0;
       
   597           while( nPad-- ) bufpt[i++] = '0';
       
   598           length = width;
       
   599         }
       
   600 #endif
       
   601         break;
       
   602       case etSIZE:
       
   603         *(va_arg(ap,int*)) = pAccum->nChar;
       
   604         length = width = 0;
       
   605         break;
       
   606       case etPERCENT:
       
   607         buf[0] = '%';
       
   608         bufpt = buf;
       
   609         length = 1;
       
   610         break;
       
   611       case etCHARX:
       
   612         c = buf[0] = va_arg(ap,int);
       
   613         if( precision>=0 ){
       
   614           for(idx=1; idx<precision; idx++) buf[idx] = c;
       
   615           length = precision;
       
   616         }else{
       
   617           length =1;
       
   618         }
       
   619         bufpt = buf;
       
   620         break;
       
   621       case etSTRING:
       
   622       case etDYNSTRING:
       
   623         bufpt = va_arg(ap,char*);
       
   624         if( bufpt==0 ){
       
   625           bufpt = "";
       
   626         }else if( xtype==etDYNSTRING ){
       
   627           zExtra = bufpt;
       
   628         }
       
   629         if( precision>=0 ){
       
   630           for(length=0; length<precision && bufpt[length]; length++){}
       
   631         }else{
       
   632           length = strlen(bufpt);
       
   633         }
       
   634         break;
       
   635       case etSQLESCAPE:
       
   636       case etSQLESCAPE2:
       
   637       case etSQLESCAPE3: {
       
   638         int i, j, n, ch, isnull;
       
   639         int needQuote;
       
   640         char q = ((xtype==etSQLESCAPE3)?'"':'\'');   /* Quote character */
       
   641         char *escarg = va_arg(ap,char*);
       
   642         isnull = escarg==0;
       
   643         if( isnull ) escarg = (xtype==etSQLESCAPE2 ? "NULL" : "(NULL)");
       
   644         for(i=n=0; (ch=escarg[i])!=0; i++){
       
   645           if( ch==q )  n++;
       
   646         }
       
   647         needQuote = !isnull && xtype==etSQLESCAPE2;
       
   648         n += i + 1 + needQuote*2;
       
   649         if( n>etBUFSIZE ){
       
   650           bufpt = zExtra = sqlite3Malloc( n );
       
   651           if( bufpt==0 ) return;
       
   652         }else{
       
   653           bufpt = buf;
       
   654         }
       
   655         j = 0;
       
   656         if( needQuote ) bufpt[j++] = q;
       
   657         for(i=0; (ch=escarg[i])!=0; i++){
       
   658           bufpt[j++] = ch;
       
   659           if( ch==q ) bufpt[j++] = ch;
       
   660         }
       
   661         if( needQuote ) bufpt[j++] = q;
       
   662         bufpt[j] = 0;
       
   663         length = j;
       
   664         /* The precision is ignored on %q and %Q */
       
   665         /* if( precision>=0 && precision<length ) length = precision; */
       
   666         break;
       
   667       }
       
   668       case etTOKEN: {
       
   669         Token *pToken = va_arg(ap, Token*);
       
   670         if( pToken ){
       
   671           sqlite3StrAccumAppend(pAccum, (const char*)pToken->z, pToken->n);
       
   672         }
       
   673         length = width = 0;
       
   674         break;
       
   675       }
       
   676       case etSRCLIST: {
       
   677         SrcList *pSrc = va_arg(ap, SrcList*);
       
   678         int k = va_arg(ap, int);
       
   679         struct SrcList_item *pItem = &pSrc->a[k];
       
   680         assert( k>=0 && k<pSrc->nSrc );
       
   681         if( pItem->zDatabase ){
       
   682           sqlite3StrAccumAppend(pAccum, pItem->zDatabase, -1);
       
   683           sqlite3StrAccumAppend(pAccum, ".", 1);
       
   684         }
       
   685         sqlite3StrAccumAppend(pAccum, pItem->zName, -1);
       
   686         length = width = 0;
       
   687         break;
       
   688       }
       
   689     }/* End switch over the format type */
       
   690     /*
       
   691     ** The text of the conversion is pointed to by "bufpt" and is
       
   692     ** "length" characters long.  The field width is "width".  Do
       
   693     ** the output.
       
   694     */
       
   695     if( !flag_leftjustify ){
       
   696       register int nspace;
       
   697       nspace = width-length;
       
   698       if( nspace>0 ){
       
   699         appendSpace(pAccum, nspace);
       
   700       }
       
   701     }
       
   702     if( length>0 ){
       
   703       sqlite3StrAccumAppend(pAccum, bufpt, length);
       
   704     }
       
   705     if( flag_leftjustify ){
       
   706       register int nspace;
       
   707       nspace = width-length;
       
   708       if( nspace>0 ){
       
   709         appendSpace(pAccum, nspace);
       
   710       }
       
   711     }
       
   712     if( zExtra ){
       
   713       sqlite3_free(zExtra);
       
   714     }
       
   715   }/* End for loop over the format string */
       
   716 } /* End of function */
       
   717 
       
   718 /*
       
   719 ** Append N bytes of text from z to the StrAccum object.
       
   720 */
       
   721 void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
       
   722   if( p->tooBig | p->mallocFailed ){
       
   723     return;
       
   724   }
       
   725   if( N<0 ){
       
   726     N = strlen(z);
       
   727   }
       
   728   if( N==0 ){
       
   729     return;
       
   730   }
       
   731   if( p->nChar+N >= p->nAlloc ){
       
   732     char *zNew;
       
   733     if( !p->useMalloc ){
       
   734       p->tooBig = 1;
       
   735       N = p->nAlloc - p->nChar - 1;
       
   736       if( N<=0 ){
       
   737         return;
       
   738       }
       
   739     }else{
       
   740       i64 szNew = p->nChar;
       
   741       szNew += N + 1;
       
   742       if( szNew > p->mxAlloc ){
       
   743         sqlite3StrAccumReset(p);
       
   744         p->tooBig = 1;
       
   745         return;
       
   746       }else{
       
   747         p->nAlloc = szNew;
       
   748       }
       
   749       zNew = sqlite3DbMallocRaw(p->db, p->nAlloc );
       
   750       if( zNew ){
       
   751         memcpy(zNew, p->zText, p->nChar);
       
   752         sqlite3StrAccumReset(p);
       
   753         p->zText = zNew;
       
   754       }else{
       
   755         p->mallocFailed = 1;
       
   756         sqlite3StrAccumReset(p);
       
   757         return;
       
   758       }
       
   759     }
       
   760   }
       
   761   memcpy(&p->zText[p->nChar], z, N);
       
   762   p->nChar += N;
       
   763 }
       
   764 
       
   765 /*
       
   766 ** Finish off a string by making sure it is zero-terminated.
       
   767 ** Return a pointer to the resulting string.  Return a NULL
       
   768 ** pointer if any kind of error was encountered.
       
   769 */
       
   770 char *sqlite3StrAccumFinish(StrAccum *p){
       
   771   if( p->zText ){
       
   772     p->zText[p->nChar] = 0;
       
   773     if( p->useMalloc && p->zText==p->zBase ){
       
   774       p->zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
       
   775       if( p->zText ){
       
   776         memcpy(p->zText, p->zBase, p->nChar+1);
       
   777       }else{
       
   778         p->mallocFailed = 1;
       
   779       }
       
   780     }
       
   781   }
       
   782   return p->zText;
       
   783 }
       
   784 
       
   785 /*
       
   786 ** Reset an StrAccum string.  Reclaim all malloced memory.
       
   787 */
       
   788 void sqlite3StrAccumReset(StrAccum *p){
       
   789   if( p->zText!=p->zBase ){
       
   790     sqlite3DbFree(p->db, p->zText);
       
   791   }
       
   792   p->zText = 0;
       
   793 }
       
   794 
       
   795 /*
       
   796 ** Initialize a string accumulator
       
   797 */
       
   798 void sqlite3StrAccumInit(StrAccum *p, char *zBase, int n, int mx){
       
   799   p->zText = p->zBase = zBase;
       
   800   p->db = 0;
       
   801   p->nChar = 0;
       
   802   p->nAlloc = n;
       
   803   p->mxAlloc = mx;
       
   804   p->useMalloc = 1;
       
   805   p->tooBig = 0;
       
   806   p->mallocFailed = 0;
       
   807 }
       
   808 
       
   809 /*
       
   810 ** Print into memory obtained from sqliteMalloc().  Use the internal
       
   811 ** %-conversion extensions.
       
   812 */
       
   813 char *sqlite3VMPrintf(sqlite3 *db, const char *zFormat, va_list ap){
       
   814   char *z;
       
   815   char zBase[SQLITE_PRINT_BUF_SIZE];
       
   816   StrAccum acc;
       
   817   sqlite3StrAccumInit(&acc, zBase, sizeof(zBase),
       
   818                       db ? db->aLimit[SQLITE_LIMIT_LENGTH] : SQLITE_MAX_LENGTH);
       
   819   acc.db = db;
       
   820   sqlite3VXPrintf(&acc, 1, zFormat, ap);
       
   821   z = sqlite3StrAccumFinish(&acc);
       
   822   if( acc.mallocFailed && db ){
       
   823     db->mallocFailed = 1;
       
   824   }
       
   825   return z;
       
   826 }
       
   827 
       
   828 /*
       
   829 ** Print into memory obtained from sqliteMalloc().  Use the internal
       
   830 ** %-conversion extensions.
       
   831 */
       
   832 char *sqlite3MPrintf(sqlite3 *db, const char *zFormat, ...){
       
   833   va_list ap;
       
   834   char *z;
       
   835   va_start(ap, zFormat);
       
   836   z = sqlite3VMPrintf(db, zFormat, ap);
       
   837   va_end(ap);
       
   838   return z;
       
   839 }
       
   840 
       
   841 /*
       
   842 ** Like sqlite3MPrintf(), but call sqlite3DbFree() on zStr after formatting
       
   843 ** the string and before returnning.  This routine is intended to be used
       
   844 ** to modify an existing string.  For example:
       
   845 **
       
   846 **       x = sqlite3MPrintf(db, x, "prefix %s suffix", x);
       
   847 **
       
   848 */
       
   849 char *sqlite3MAppendf(sqlite3 *db, char *zStr, const char *zFormat, ...){
       
   850   va_list ap;
       
   851   char *z;
       
   852   va_start(ap, zFormat);
       
   853   z = sqlite3VMPrintf(db, zFormat, ap);
       
   854   va_end(ap);
       
   855   sqlite3DbFree(db, zStr);
       
   856   return z;
       
   857 }
       
   858 
       
   859 /*
       
   860 ** Print into memory obtained from sqlite3_malloc().  Omit the internal
       
   861 ** %-conversion extensions.
       
   862 */
       
   863 char *sqlite3_vmprintf(const char *zFormat, va_list ap){
       
   864   char *z;
       
   865   char zBase[SQLITE_PRINT_BUF_SIZE];
       
   866   StrAccum acc;
       
   867 #ifndef SQLITE_OMIT_AUTOINIT
       
   868   if( sqlite3_initialize() ) return 0;
       
   869 #endif
       
   870   sqlite3StrAccumInit(&acc, zBase, sizeof(zBase), SQLITE_MAX_LENGTH);
       
   871   sqlite3VXPrintf(&acc, 0, zFormat, ap);
       
   872   z = sqlite3StrAccumFinish(&acc);
       
   873   return z;
       
   874 }
       
   875 
       
   876 /*
       
   877 ** Print into memory obtained from sqlite3_malloc()().  Omit the internal
       
   878 ** %-conversion extensions.
       
   879 */
       
   880 char *sqlite3_mprintf(const char *zFormat, ...){
       
   881   va_list ap;
       
   882   char *z;
       
   883 #ifndef SQLITE_OMIT_AUTOINIT
       
   884   if( sqlite3_initialize() ) return 0;
       
   885 #endif
       
   886   va_start(ap, zFormat);
       
   887   z = sqlite3_vmprintf(zFormat, ap);
       
   888   va_end(ap);
       
   889   return z;
       
   890 }
       
   891 
       
   892 /*
       
   893 ** sqlite3_snprintf() works like snprintf() except that it ignores the
       
   894 ** current locale settings.  This is important for SQLite because we
       
   895 ** are not able to use a "," as the decimal point in place of "." as
       
   896 ** specified by some locales.
       
   897 */
       
   898 char *sqlite3_snprintf(int n, char *zBuf, const char *zFormat, ...){
       
   899   char *z;
       
   900   va_list ap;
       
   901   StrAccum acc;
       
   902 
       
   903   if( n<=0 ){
       
   904     return zBuf;
       
   905   }
       
   906   sqlite3StrAccumInit(&acc, zBuf, n, 0);
       
   907   acc.useMalloc = 0;
       
   908   va_start(ap,zFormat);
       
   909   sqlite3VXPrintf(&acc, 0, zFormat, ap);
       
   910   va_end(ap);
       
   911   z = sqlite3StrAccumFinish(&acc);
       
   912   return z;
       
   913 }
       
   914 
       
   915 #if defined(SQLITE_DEBUG)
       
   916 /*
       
   917 ** A version of printf() that understands %lld.  Used for debugging.
       
   918 ** The printf() built into some versions of windows does not understand %lld
       
   919 ** and segfaults if you give it a long long int.
       
   920 */
       
   921 void sqlite3DebugPrintf(const char *zFormat, ...){
       
   922   va_list ap;
       
   923   StrAccum acc;
       
   924   char zBuf[500];
       
   925   sqlite3StrAccumInit(&acc, zBuf, sizeof(zBuf), 0);
       
   926   acc.useMalloc = 0;
       
   927   va_start(ap,zFormat);
       
   928   sqlite3VXPrintf(&acc, 0, zFormat, ap);
       
   929   va_end(ap);
       
   930   sqlite3StrAccumFinish(&acc);
       
   931   fprintf(stdout,"%s", zBuf);
       
   932   fflush(stdout);
       
   933 }
       
   934 #endif