xref: /sqlite-3.40.0/src/printf.c (revision dedd51ae)
1 /*
2 ** The "printf" code that follows dates from the 1980's.  It is in
3 ** the public domain.
4 **
5 **************************************************************************
6 **
7 ** This file contains code for a set of "printf"-like routines.  These
8 ** routines format strings much like the printf() from the standard C
9 ** library, though the implementation here has enhancements to support
10 ** SQLite.
11 */
12 #include "sqliteInt.h"
13 
14 /*
15 ** Conversion types fall into various categories as defined by the
16 ** following enumeration.
17 */
18 #define etRADIX       0 /* non-decimal integer types.  %x %o */
19 #define etFLOAT       1 /* Floating point.  %f */
20 #define etEXP         2 /* Exponentional notation. %e and %E */
21 #define etGENERIC     3 /* Floating or exponential, depending on exponent. %g */
22 #define etSIZE        4 /* Return number of characters processed so far. %n */
23 #define etSTRING      5 /* Strings. %s */
24 #define etDYNSTRING   6 /* Dynamically allocated strings. %z */
25 #define etPERCENT     7 /* Percent symbol. %% */
26 #define etCHARX       8 /* Characters. %c */
27 /* The rest are extensions, not normally found in printf() */
28 #define etSQLESCAPE   9 /* Strings with '\'' doubled.  %q */
29 #define etSQLESCAPE2 10 /* Strings with '\'' doubled and enclosed in '',
30                           NULL pointers replaced by SQL NULL.  %Q */
31 #define etTOKEN      11 /* a pointer to a Token structure */
32 #define etSRCITEM    12 /* a pointer to a SrcItem */
33 #define etPOINTER    13 /* The %p conversion */
34 #define etSQLESCAPE3 14 /* %w -> Strings with '\"' doubled */
35 #define etORDINAL    15 /* %r -> 1st, 2nd, 3rd, 4th, etc.  English only */
36 #define etDECIMAL    16 /* %d or %u, but not %x, %o */
37 
38 #define etINVALID    17 /* Any unrecognized conversion type */
39 
40 
41 /*
42 ** An "etByte" is an 8-bit unsigned value.
43 */
44 typedef unsigned char etByte;
45 
46 /*
47 ** Each builtin conversion character (ex: the 'd' in "%d") is described
48 ** by an instance of the following structure
49 */
50 typedef struct et_info {   /* Information about each format field */
51   char fmttype;            /* The format field code letter */
52   etByte base;             /* The base for radix conversion */
53   etByte flags;            /* One or more of FLAG_ constants below */
54   etByte type;             /* Conversion paradigm */
55   etByte charset;          /* Offset into aDigits[] of the digits string */
56   etByte prefix;           /* Offset into aPrefix[] of the prefix string */
57 } et_info;
58 
59 /*
60 ** Allowed values for et_info.flags
61 */
62 #define FLAG_SIGNED    1     /* True if the value to convert is signed */
63 #define FLAG_STRING    4     /* Allow infinite precision */
64 
65 
66 /*
67 ** The following table is searched linearly, so it is good to put the
68 ** most frequently used conversion types first.
69 */
70 static const char aDigits[] = "0123456789ABCDEF0123456789abcdef";
71 static const char aPrefix[] = "-x0\000X0";
72 static const et_info fmtinfo[] = {
73   {  'd', 10, 1, etDECIMAL,    0,  0 },
74   {  's',  0, 4, etSTRING,     0,  0 },
75   {  'g',  0, 1, etGENERIC,    30, 0 },
76   {  'z',  0, 4, etDYNSTRING,  0,  0 },
77   {  'q',  0, 4, etSQLESCAPE,  0,  0 },
78   {  'Q',  0, 4, etSQLESCAPE2, 0,  0 },
79   {  'w',  0, 4, etSQLESCAPE3, 0,  0 },
80   {  'c',  0, 0, etCHARX,      0,  0 },
81   {  'o',  8, 0, etRADIX,      0,  2 },
82   {  'u', 10, 0, etDECIMAL,    0,  0 },
83   {  'x', 16, 0, etRADIX,      16, 1 },
84   {  'X', 16, 0, etRADIX,      0,  4 },
85 #ifndef SQLITE_OMIT_FLOATING_POINT
86   {  'f',  0, 1, etFLOAT,      0,  0 },
87   {  'e',  0, 1, etEXP,        30, 0 },
88   {  'E',  0, 1, etEXP,        14, 0 },
89   {  'G',  0, 1, etGENERIC,    14, 0 },
90 #endif
91   {  'i', 10, 1, etDECIMAL,    0,  0 },
92   {  'n',  0, 0, etSIZE,       0,  0 },
93   {  '%',  0, 0, etPERCENT,    0,  0 },
94   {  'p', 16, 0, etPOINTER,    0,  1 },
95 
96   /* All the rest are undocumented and are for internal use only */
97   {  'T',  0, 0, etTOKEN,      0,  0 },
98   {  'S',  0, 0, etSRCITEM,    0,  0 },
99   {  'r', 10, 1, etORDINAL,    0,  0 },
100 };
101 
102 /* Notes:
103 **
104 **    %S    Takes a pointer to SrcItem.  Shows name or database.name
105 **    %!S   Like %S but prefer the zName over the zAlias
106 */
107 
108 /* Floating point constants used for rounding */
109 static const double arRound[] = {
110   5.0e-01, 5.0e-02, 5.0e-03, 5.0e-04, 5.0e-05,
111   5.0e-06, 5.0e-07, 5.0e-08, 5.0e-09, 5.0e-10,
112 };
113 
114 /*
115 ** If SQLITE_OMIT_FLOATING_POINT is defined, then none of the floating point
116 ** conversions will work.
117 */
118 #ifndef SQLITE_OMIT_FLOATING_POINT
119 /*
120 ** "*val" is a double such that 0.1 <= *val < 10.0
121 ** Return the ascii code for the leading digit of *val, then
122 ** multiply "*val" by 10.0 to renormalize.
123 **
124 ** Example:
125 **     input:     *val = 3.14159
126 **     output:    *val = 1.4159    function return = '3'
127 **
128 ** The counter *cnt is incremented each time.  After counter exceeds
129 ** 16 (the number of significant digits in a 64-bit float) '0' is
130 ** always returned.
131 */
132 static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
133   int digit;
134   LONGDOUBLE_TYPE d;
135   if( (*cnt)<=0 ) return '0';
136   (*cnt)--;
137   digit = (int)*val;
138   d = digit;
139   digit += '0';
140   *val = (*val - d)*10.0;
141   return (char)digit;
142 }
143 #endif /* SQLITE_OMIT_FLOATING_POINT */
144 
145 /*
146 ** Set the StrAccum object to an error mode.
147 */
148 void sqlite3StrAccumSetError(StrAccum *p, u8 eError){
149   assert( eError==SQLITE_NOMEM || eError==SQLITE_TOOBIG );
150   p->accError = eError;
151   if( p->mxAlloc ) sqlite3_str_reset(p);
152   if( eError==SQLITE_TOOBIG ) sqlite3ErrorToParser(p->db, eError);
153 }
154 
155 /*
156 ** Extra argument values from a PrintfArguments object
157 */
158 static sqlite3_int64 getIntArg(PrintfArguments *p){
159   if( p->nArg<=p->nUsed ) return 0;
160   return sqlite3_value_int64(p->apArg[p->nUsed++]);
161 }
162 static double getDoubleArg(PrintfArguments *p){
163   if( p->nArg<=p->nUsed ) return 0.0;
164   return sqlite3_value_double(p->apArg[p->nUsed++]);
165 }
166 static char *getTextArg(PrintfArguments *p){
167   if( p->nArg<=p->nUsed ) return 0;
168   return (char*)sqlite3_value_text(p->apArg[p->nUsed++]);
169 }
170 
171 /*
172 ** Allocate memory for a temporary buffer needed for printf rendering.
173 **
174 ** If the requested size of the temp buffer is larger than the size
175 ** of the output buffer in pAccum, then cause an SQLITE_TOOBIG error.
176 ** Do the size check before the memory allocation to prevent rogue
177 ** SQL from requesting large allocations using the precision or width
178 ** field of the printf() function.
179 */
180 static char *printfTempBuf(sqlite3_str *pAccum, sqlite3_int64 n){
181   char *z;
182   if( pAccum->accError ) return 0;
183   if( n>pAccum->nAlloc && n>pAccum->mxAlloc ){
184     sqlite3StrAccumSetError(pAccum, SQLITE_TOOBIG);
185     return 0;
186   }
187   z = sqlite3DbMallocRaw(pAccum->db, n);
188   if( z==0 ){
189     sqlite3StrAccumSetError(pAccum, SQLITE_NOMEM);
190   }
191   return z;
192 }
193 
194 /*
195 ** On machines with a small stack size, you can redefine the
196 ** SQLITE_PRINT_BUF_SIZE to be something smaller, if desired.
197 */
198 #ifndef SQLITE_PRINT_BUF_SIZE
199 # define SQLITE_PRINT_BUF_SIZE 70
200 #endif
201 #define etBUFSIZE SQLITE_PRINT_BUF_SIZE  /* Size of the output buffer */
202 
203 /*
204 ** Hard limit on the precision of floating-point conversions.
205 */
206 #ifndef SQLITE_PRINTF_PRECISION_LIMIT
207 # define SQLITE_FP_PRECISION_LIMIT 100000000
208 #endif
209 
210 /*
211 ** Render a string given by "fmt" into the StrAccum object.
212 */
213 void sqlite3_str_vappendf(
214   sqlite3_str *pAccum,       /* Accumulate results here */
215   const char *fmt,           /* Format string */
216   va_list ap                 /* arguments */
217 ){
218   int c;                     /* Next character in the format string */
219   char *bufpt;               /* Pointer to the conversion buffer */
220   int precision;             /* Precision of the current field */
221   int length;                /* Length of the field */
222   int idx;                   /* A general purpose loop counter */
223   int width;                 /* Width of the current field */
224   etByte flag_leftjustify;   /* True if "-" flag is present */
225   etByte flag_prefix;        /* '+' or ' ' or 0 for prefix */
226   etByte flag_alternateform; /* True if "#" flag is present */
227   etByte flag_altform2;      /* True if "!" flag is present */
228   etByte flag_zeropad;       /* True if field width constant starts with zero */
229   etByte flag_long;          /* 1 for the "l" flag, 2 for "ll", 0 by default */
230   etByte done;               /* Loop termination flag */
231   etByte cThousand;          /* Thousands separator for %d and %u */
232   etByte xtype = etINVALID;  /* Conversion paradigm */
233   u8 bArgList;               /* True for SQLITE_PRINTF_SQLFUNC */
234   char prefix;               /* Prefix character.  "+" or "-" or " " or '\0'. */
235   sqlite_uint64 longvalue;   /* Value for integer types */
236   LONGDOUBLE_TYPE realvalue; /* Value for real types */
237   const et_info *infop;      /* Pointer to the appropriate info structure */
238   char *zOut;                /* Rendering buffer */
239   int nOut;                  /* Size of the rendering buffer */
240   char *zExtra = 0;          /* Malloced memory used by some conversion */
241 #ifndef SQLITE_OMIT_FLOATING_POINT
242   int  exp, e2;              /* exponent of real numbers */
243   int nsd;                   /* Number of significant digits returned */
244   double rounder;            /* Used for rounding floating point values */
245   etByte flag_dp;            /* True if decimal point should be shown */
246   etByte flag_rtz;           /* True if trailing zeros should be removed */
247 #endif
248   PrintfArguments *pArgList = 0; /* Arguments for SQLITE_PRINTF_SQLFUNC */
249   char buf[etBUFSIZE];       /* Conversion buffer */
250 
251   /* pAccum never starts out with an empty buffer that was obtained from
252   ** malloc().  This precondition is required by the mprintf("%z...")
253   ** optimization. */
254   assert( pAccum->nChar>0 || (pAccum->printfFlags&SQLITE_PRINTF_MALLOCED)==0 );
255 
256   bufpt = 0;
257   if( (pAccum->printfFlags & SQLITE_PRINTF_SQLFUNC)!=0 ){
258     pArgList = va_arg(ap, PrintfArguments*);
259     bArgList = 1;
260   }else{
261     bArgList = 0;
262   }
263   for(; (c=(*fmt))!=0; ++fmt){
264     if( c!='%' ){
265       bufpt = (char *)fmt;
266 #if HAVE_STRCHRNUL
267       fmt = strchrnul(fmt, '%');
268 #else
269       do{ fmt++; }while( *fmt && *fmt != '%' );
270 #endif
271       sqlite3_str_append(pAccum, bufpt, (int)(fmt - bufpt));
272       if( *fmt==0 ) break;
273     }
274     if( (c=(*++fmt))==0 ){
275       sqlite3_str_append(pAccum, "%", 1);
276       break;
277     }
278     /* Find out what flags are present */
279     flag_leftjustify = flag_prefix = cThousand =
280      flag_alternateform = flag_altform2 = flag_zeropad = 0;
281     done = 0;
282     width = 0;
283     flag_long = 0;
284     precision = -1;
285     do{
286       switch( c ){
287         case '-':   flag_leftjustify = 1;     break;
288         case '+':   flag_prefix = '+';        break;
289         case ' ':   flag_prefix = ' ';        break;
290         case '#':   flag_alternateform = 1;   break;
291         case '!':   flag_altform2 = 1;        break;
292         case '0':   flag_zeropad = 1;         break;
293         case ',':   cThousand = ',';          break;
294         default:    done = 1;                 break;
295         case 'l': {
296           flag_long = 1;
297           c = *++fmt;
298           if( c=='l' ){
299             c = *++fmt;
300             flag_long = 2;
301           }
302           done = 1;
303           break;
304         }
305         case '1': case '2': case '3': case '4': case '5':
306         case '6': case '7': case '8': case '9': {
307           unsigned wx = c - '0';
308           while( (c = *++fmt)>='0' && c<='9' ){
309             wx = wx*10 + c - '0';
310           }
311           testcase( wx>0x7fffffff );
312           width = wx & 0x7fffffff;
313 #ifdef SQLITE_PRINTF_PRECISION_LIMIT
314           if( width>SQLITE_PRINTF_PRECISION_LIMIT ){
315             width = SQLITE_PRINTF_PRECISION_LIMIT;
316           }
317 #endif
318           if( c!='.' && c!='l' ){
319             done = 1;
320           }else{
321             fmt--;
322           }
323           break;
324         }
325         case '*': {
326           if( bArgList ){
327             width = (int)getIntArg(pArgList);
328           }else{
329             width = va_arg(ap,int);
330           }
331           if( width<0 ){
332             flag_leftjustify = 1;
333             width = width >= -2147483647 ? -width : 0;
334           }
335 #ifdef SQLITE_PRINTF_PRECISION_LIMIT
336           if( width>SQLITE_PRINTF_PRECISION_LIMIT ){
337             width = SQLITE_PRINTF_PRECISION_LIMIT;
338           }
339 #endif
340           if( (c = fmt[1])!='.' && c!='l' ){
341             c = *++fmt;
342             done = 1;
343           }
344           break;
345         }
346         case '.': {
347           c = *++fmt;
348           if( c=='*' ){
349             if( bArgList ){
350               precision = (int)getIntArg(pArgList);
351             }else{
352               precision = va_arg(ap,int);
353             }
354             if( precision<0 ){
355               precision = precision >= -2147483647 ? -precision : -1;
356             }
357             c = *++fmt;
358           }else{
359             unsigned px = 0;
360             while( c>='0' && c<='9' ){
361               px = px*10 + c - '0';
362               c = *++fmt;
363             }
364             testcase( px>0x7fffffff );
365             precision = px & 0x7fffffff;
366           }
367 #ifdef SQLITE_PRINTF_PRECISION_LIMIT
368           if( precision>SQLITE_PRINTF_PRECISION_LIMIT ){
369             precision = SQLITE_PRINTF_PRECISION_LIMIT;
370           }
371 #endif
372           if( c=='l' ){
373             --fmt;
374           }else{
375             done = 1;
376           }
377           break;
378         }
379       }
380     }while( !done && (c=(*++fmt))!=0 );
381 
382     /* Fetch the info entry for the field */
383     infop = &fmtinfo[0];
384     xtype = etINVALID;
385     for(idx=0; idx<ArraySize(fmtinfo); idx++){
386       if( c==fmtinfo[idx].fmttype ){
387         infop = &fmtinfo[idx];
388         xtype = infop->type;
389         break;
390       }
391     }
392 
393     /*
394     ** At this point, variables are initialized as follows:
395     **
396     **   flag_alternateform          TRUE if a '#' is present.
397     **   flag_altform2               TRUE if a '!' is present.
398     **   flag_prefix                 '+' or ' ' or zero
399     **   flag_leftjustify            TRUE if a '-' is present or if the
400     **                               field width was negative.
401     **   flag_zeropad                TRUE if the width began with 0.
402     **   flag_long                   1 for "l", 2 for "ll"
403     **   width                       The specified field width.  This is
404     **                               always non-negative.  Zero is the default.
405     **   precision                   The specified precision.  The default
406     **                               is -1.
407     **   xtype                       The class of the conversion.
408     **   infop                       Pointer to the appropriate info struct.
409     */
410     assert( width>=0 );
411     assert( precision>=(-1) );
412     switch( xtype ){
413       case etPOINTER:
414         flag_long = sizeof(char*)==sizeof(i64) ? 2 :
415                      sizeof(char*)==sizeof(long int) ? 1 : 0;
416         /* no break */ deliberate_fall_through
417       case etORDINAL:
418       case etRADIX:
419         cThousand = 0;
420         /* no break */ deliberate_fall_through
421       case etDECIMAL:
422         if( infop->flags & FLAG_SIGNED ){
423           i64 v;
424           if( bArgList ){
425             v = getIntArg(pArgList);
426           }else if( flag_long ){
427             if( flag_long==2 ){
428               v = va_arg(ap,i64) ;
429             }else{
430               v = va_arg(ap,long int);
431             }
432           }else{
433             v = va_arg(ap,int);
434           }
435           if( v<0 ){
436             testcase( v==SMALLEST_INT64 );
437             testcase( v==(-1) );
438             longvalue = ~v;
439             longvalue++;
440             prefix = '-';
441           }else{
442             longvalue = v;
443             prefix = flag_prefix;
444           }
445         }else{
446           if( bArgList ){
447             longvalue = (u64)getIntArg(pArgList);
448           }else if( flag_long ){
449             if( flag_long==2 ){
450               longvalue = va_arg(ap,u64);
451             }else{
452               longvalue = va_arg(ap,unsigned long int);
453             }
454           }else{
455             longvalue = va_arg(ap,unsigned int);
456           }
457           prefix = 0;
458         }
459         if( longvalue==0 ) flag_alternateform = 0;
460         if( flag_zeropad && precision<width-(prefix!=0) ){
461           precision = width-(prefix!=0);
462         }
463         if( precision<etBUFSIZE-10-etBUFSIZE/3 ){
464           nOut = etBUFSIZE;
465           zOut = buf;
466         }else{
467           u64 n;
468           n = (u64)precision + 10;
469           if( cThousand ) n += precision/3;
470           zOut = zExtra = printfTempBuf(pAccum, n);
471           if( zOut==0 ) return;
472           nOut = (int)n;
473         }
474         bufpt = &zOut[nOut-1];
475         if( xtype==etORDINAL ){
476           static const char zOrd[] = "thstndrd";
477           int x = (int)(longvalue % 10);
478           if( x>=4 || (longvalue/10)%10==1 ){
479             x = 0;
480           }
481           *(--bufpt) = zOrd[x*2+1];
482           *(--bufpt) = zOrd[x*2];
483         }
484         {
485           const char *cset = &aDigits[infop->charset];
486           u8 base = infop->base;
487           do{                                           /* Convert to ascii */
488             *(--bufpt) = cset[longvalue%base];
489             longvalue = longvalue/base;
490           }while( longvalue>0 );
491         }
492         length = (int)(&zOut[nOut-1]-bufpt);
493         while( precision>length ){
494           *(--bufpt) = '0';                             /* Zero pad */
495           length++;
496         }
497         if( cThousand ){
498           int nn = (length - 1)/3;  /* Number of "," to insert */
499           int ix = (length - 1)%3 + 1;
500           bufpt -= nn;
501           for(idx=0; nn>0; idx++){
502             bufpt[idx] = bufpt[idx+nn];
503             ix--;
504             if( ix==0 ){
505               bufpt[++idx] = cThousand;
506               nn--;
507               ix = 3;
508             }
509           }
510         }
511         if( prefix ) *(--bufpt) = prefix;               /* Add sign */
512         if( flag_alternateform && infop->prefix ){      /* Add "0" or "0x" */
513           const char *pre;
514           char x;
515           pre = &aPrefix[infop->prefix];
516           for(; (x=(*pre))!=0; pre++) *(--bufpt) = x;
517         }
518         length = (int)(&zOut[nOut-1]-bufpt);
519         break;
520       case etFLOAT:
521       case etEXP:
522       case etGENERIC:
523         if( bArgList ){
524           realvalue = getDoubleArg(pArgList);
525         }else{
526           realvalue = va_arg(ap,double);
527         }
528 #ifdef SQLITE_OMIT_FLOATING_POINT
529         length = 0;
530 #else
531         if( precision<0 ) precision = 6;         /* Set default precision */
532 #ifdef SQLITE_FP_PRECISION_LIMIT
533         if( precision>SQLITE_FP_PRECISION_LIMIT ){
534           precision = SQLITE_FP_PRECISION_LIMIT;
535         }
536 #endif
537         if( realvalue<0.0 ){
538           realvalue = -realvalue;
539           prefix = '-';
540         }else{
541           prefix = flag_prefix;
542         }
543         if( xtype==etGENERIC && precision>0 ) precision--;
544         testcase( precision>0xfff );
545         idx = precision & 0xfff;
546         rounder = arRound[idx%10];
547         while( idx>=10 ){ rounder *= 1.0e-10; idx -= 10; }
548         if( xtype==etFLOAT ){
549           double rx = (double)realvalue;
550           sqlite3_uint64 u;
551           int ex;
552           memcpy(&u, &rx, sizeof(u));
553           ex = -1023 + (int)((u>>52)&0x7ff);
554           if( precision+(ex/3) < 15 ) rounder += realvalue*3e-16;
555           realvalue += rounder;
556         }
557         /* Normalize realvalue to within 10.0 > realvalue >= 1.0 */
558         exp = 0;
559         if( sqlite3IsNaN((double)realvalue) ){
560           bufpt = "NaN";
561           length = 3;
562           break;
563         }
564         if( realvalue>0.0 ){
565           LONGDOUBLE_TYPE scale = 1.0;
566           while( realvalue>=1e100*scale && exp<=350 ){ scale *= 1e100;exp+=100;}
567           while( realvalue>=1e10*scale && exp<=350 ){ scale *= 1e10; exp+=10; }
568           while( realvalue>=10.0*scale && exp<=350 ){ scale *= 10.0; exp++; }
569           realvalue /= scale;
570           while( realvalue<1e-8 ){ realvalue *= 1e8; exp-=8; }
571           while( realvalue<1.0 ){ realvalue *= 10.0; exp--; }
572           if( exp>350 ){
573             bufpt = buf;
574             buf[0] = prefix;
575             memcpy(buf+(prefix!=0),"Inf",4);
576             length = 3+(prefix!=0);
577             break;
578           }
579         }
580         bufpt = buf;
581         /*
582         ** If the field type is etGENERIC, then convert to either etEXP
583         ** or etFLOAT, as appropriate.
584         */
585         if( xtype!=etFLOAT ){
586           realvalue += rounder;
587           if( realvalue>=10.0 ){ realvalue *= 0.1; exp++; }
588         }
589         if( xtype==etGENERIC ){
590           flag_rtz = !flag_alternateform;
591           if( exp<-4 || exp>precision ){
592             xtype = etEXP;
593           }else{
594             precision = precision - exp;
595             xtype = etFLOAT;
596           }
597         }else{
598           flag_rtz = flag_altform2;
599         }
600         if( xtype==etEXP ){
601           e2 = 0;
602         }else{
603           e2 = exp;
604         }
605         {
606           i64 szBufNeeded;           /* Size of a temporary buffer needed */
607           szBufNeeded = MAX(e2,0)+(i64)precision+(i64)width+15;
608           if( szBufNeeded > etBUFSIZE ){
609             bufpt = zExtra = printfTempBuf(pAccum, szBufNeeded);
610             if( bufpt==0 ) return;
611           }
612         }
613         zOut = bufpt;
614         nsd = 16 + flag_altform2*10;
615         flag_dp = (precision>0 ?1:0) | flag_alternateform | flag_altform2;
616         /* The sign in front of the number */
617         if( prefix ){
618           *(bufpt++) = prefix;
619         }
620         /* Digits prior to the decimal point */
621         if( e2<0 ){
622           *(bufpt++) = '0';
623         }else{
624           for(; e2>=0; e2--){
625             *(bufpt++) = et_getdigit(&realvalue,&nsd);
626           }
627         }
628         /* The decimal point */
629         if( flag_dp ){
630           *(bufpt++) = '.';
631         }
632         /* "0" digits after the decimal point but before the first
633         ** significant digit of the number */
634         for(e2++; e2<0; precision--, e2++){
635           assert( precision>0 );
636           *(bufpt++) = '0';
637         }
638         /* Significant digits after the decimal point */
639         while( (precision--)>0 ){
640           *(bufpt++) = et_getdigit(&realvalue,&nsd);
641         }
642         /* Remove trailing zeros and the "." if no digits follow the "." */
643         if( flag_rtz && flag_dp ){
644           while( bufpt[-1]=='0' ) *(--bufpt) = 0;
645           assert( bufpt>zOut );
646           if( bufpt[-1]=='.' ){
647             if( flag_altform2 ){
648               *(bufpt++) = '0';
649             }else{
650               *(--bufpt) = 0;
651             }
652           }
653         }
654         /* Add the "eNNN" suffix */
655         if( xtype==etEXP ){
656           *(bufpt++) = aDigits[infop->charset];
657           if( exp<0 ){
658             *(bufpt++) = '-'; exp = -exp;
659           }else{
660             *(bufpt++) = '+';
661           }
662           if( exp>=100 ){
663             *(bufpt++) = (char)((exp/100)+'0');        /* 100's digit */
664             exp %= 100;
665           }
666           *(bufpt++) = (char)(exp/10+'0');             /* 10's digit */
667           *(bufpt++) = (char)(exp%10+'0');             /* 1's digit */
668         }
669         *bufpt = 0;
670 
671         /* The converted number is in buf[] and zero terminated. Output it.
672         ** Note that the number is in the usual order, not reversed as with
673         ** integer conversions. */
674         length = (int)(bufpt-zOut);
675         bufpt = zOut;
676 
677         /* Special case:  Add leading zeros if the flag_zeropad flag is
678         ** set and we are not left justified */
679         if( flag_zeropad && !flag_leftjustify && length < width){
680           int i;
681           int nPad = width - length;
682           for(i=width; i>=nPad; i--){
683             bufpt[i] = bufpt[i-nPad];
684           }
685           i = prefix!=0;
686           while( nPad-- ) bufpt[i++] = '0';
687           length = width;
688         }
689 #endif /* !defined(SQLITE_OMIT_FLOATING_POINT) */
690         break;
691       case etSIZE:
692         if( !bArgList ){
693           *(va_arg(ap,int*)) = pAccum->nChar;
694         }
695         length = width = 0;
696         break;
697       case etPERCENT:
698         buf[0] = '%';
699         bufpt = buf;
700         length = 1;
701         break;
702       case etCHARX:
703         if( bArgList ){
704           bufpt = getTextArg(pArgList);
705           length = 1;
706           if( bufpt ){
707             buf[0] = c = *(bufpt++);
708             if( (c&0xc0)==0xc0 ){
709               while( length<4 && (bufpt[0]&0xc0)==0x80 ){
710                 buf[length++] = *(bufpt++);
711               }
712             }
713           }else{
714             buf[0] = 0;
715           }
716         }else{
717           unsigned int ch = va_arg(ap,unsigned int);
718           if( ch<0x00080 ){
719             buf[0] = ch & 0xff;
720             length = 1;
721           }else if( ch<0x00800 ){
722             buf[0] = 0xc0 + (u8)((ch>>6)&0x1f);
723             buf[1] = 0x80 + (u8)(ch & 0x3f);
724             length = 2;
725           }else if( ch<0x10000 ){
726             buf[0] = 0xe0 + (u8)((ch>>12)&0x0f);
727             buf[1] = 0x80 + (u8)((ch>>6) & 0x3f);
728             buf[2] = 0x80 + (u8)(ch & 0x3f);
729             length = 3;
730           }else{
731             buf[0] = 0xf0 + (u8)((ch>>18) & 0x07);
732             buf[1] = 0x80 + (u8)((ch>>12) & 0x3f);
733             buf[2] = 0x80 + (u8)((ch>>6) & 0x3f);
734             buf[3] = 0x80 + (u8)(ch & 0x3f);
735             length = 4;
736           }
737         }
738         if( precision>1 ){
739           width -= precision-1;
740           if( width>1 && !flag_leftjustify ){
741             sqlite3_str_appendchar(pAccum, width-1, ' ');
742             width = 0;
743           }
744           while( precision-- > 1 ){
745             sqlite3_str_append(pAccum, buf, length);
746           }
747         }
748         bufpt = buf;
749         flag_altform2 = 1;
750         goto adjust_width_for_utf8;
751       case etSTRING:
752       case etDYNSTRING:
753         if( bArgList ){
754           bufpt = getTextArg(pArgList);
755           xtype = etSTRING;
756         }else{
757           bufpt = va_arg(ap,char*);
758         }
759         if( bufpt==0 ){
760           bufpt = "";
761         }else if( xtype==etDYNSTRING ){
762           if( pAccum->nChar==0
763            && pAccum->mxAlloc
764            && width==0
765            && precision<0
766            && pAccum->accError==0
767           ){
768             /* Special optimization for sqlite3_mprintf("%z..."):
769             ** Extend an existing memory allocation rather than creating
770             ** a new one. */
771             assert( (pAccum->printfFlags&SQLITE_PRINTF_MALLOCED)==0 );
772             pAccum->zText = bufpt;
773             pAccum->nAlloc = sqlite3DbMallocSize(pAccum->db, bufpt);
774             pAccum->nChar = 0x7fffffff & (int)strlen(bufpt);
775             pAccum->printfFlags |= SQLITE_PRINTF_MALLOCED;
776             length = 0;
777             break;
778           }
779           zExtra = bufpt;
780         }
781         if( precision>=0 ){
782           if( flag_altform2 ){
783             /* Set length to the number of bytes needed in order to display
784             ** precision characters */
785             unsigned char *z = (unsigned char*)bufpt;
786             while( precision-- > 0 && z[0] ){
787               SQLITE_SKIP_UTF8(z);
788             }
789             length = (int)(z - (unsigned char*)bufpt);
790           }else{
791             for(length=0; length<precision && bufpt[length]; length++){}
792           }
793         }else{
794           length = 0x7fffffff & (int)strlen(bufpt);
795         }
796       adjust_width_for_utf8:
797         if( flag_altform2 && width>0 ){
798           /* Adjust width to account for extra bytes in UTF-8 characters */
799           int ii = length - 1;
800           while( ii>=0 ) if( (bufpt[ii--] & 0xc0)==0x80 ) width++;
801         }
802         break;
803       case etSQLESCAPE:           /* %q: Escape ' characters */
804       case etSQLESCAPE2:          /* %Q: Escape ' and enclose in '...' */
805       case etSQLESCAPE3: {        /* %w: Escape " characters */
806         int i, j, k, n, isnull;
807         int needQuote;
808         char ch;
809         char q = ((xtype==etSQLESCAPE3)?'"':'\'');   /* Quote character */
810         char *escarg;
811 
812         if( bArgList ){
813           escarg = getTextArg(pArgList);
814         }else{
815           escarg = va_arg(ap,char*);
816         }
817         isnull = escarg==0;
818         if( isnull ) escarg = (xtype==etSQLESCAPE2 ? "NULL" : "(NULL)");
819         /* For %q, %Q, and %w, the precision is the number of bytes (or
820         ** characters if the ! flags is present) to use from the input.
821         ** Because of the extra quoting characters inserted, the number
822         ** of output characters may be larger than the precision.
823         */
824         k = precision;
825         for(i=n=0; k!=0 && (ch=escarg[i])!=0; i++, k--){
826           if( ch==q )  n++;
827           if( flag_altform2 && (ch&0xc0)==0xc0 ){
828             while( (escarg[i+1]&0xc0)==0x80 ){ i++; }
829           }
830         }
831         needQuote = !isnull && xtype==etSQLESCAPE2;
832         n += i + 3;
833         if( n>etBUFSIZE ){
834           bufpt = zExtra = printfTempBuf(pAccum, n);
835           if( bufpt==0 ) return;
836         }else{
837           bufpt = buf;
838         }
839         j = 0;
840         if( needQuote ) bufpt[j++] = q;
841         k = i;
842         for(i=0; i<k; i++){
843           bufpt[j++] = ch = escarg[i];
844           if( ch==q ) bufpt[j++] = ch;
845         }
846         if( needQuote ) bufpt[j++] = q;
847         bufpt[j] = 0;
848         length = j;
849         goto adjust_width_for_utf8;
850       }
851       case etTOKEN: {
852         if( (pAccum->printfFlags & SQLITE_PRINTF_INTERNAL)==0 ) return;
853         if( flag_alternateform ){
854           /* %#T means an Expr pointer that uses Expr.u.zToken */
855           Expr *pExpr = va_arg(ap,Expr*);
856           if( ALWAYS(pExpr) && ALWAYS(!ExprHasProperty(pExpr,EP_IntValue)) ){
857             sqlite3_str_appendall(pAccum, (const char*)pExpr->u.zToken);
858             sqlite3RecordErrorOffsetOfExpr(pAccum->db, pExpr);
859           }
860         }else{
861           /* %T means a Token pointer */
862           Token *pToken = va_arg(ap, Token*);
863           assert( bArgList==0 );
864           if( pToken && pToken->n ){
865             sqlite3_str_append(pAccum, (const char*)pToken->z, pToken->n);
866             sqlite3RecordErrorByteOffset(pAccum->db, pToken->z);
867           }
868         }
869         length = width = 0;
870         break;
871       }
872       case etSRCITEM: {
873         SrcItem *pItem;
874         if( (pAccum->printfFlags & SQLITE_PRINTF_INTERNAL)==0 ) return;
875         pItem = va_arg(ap, SrcItem*);
876         assert( bArgList==0 );
877         if( pItem->zAlias && !flag_altform2 ){
878           sqlite3_str_appendall(pAccum, pItem->zAlias);
879         }else if( pItem->zName ){
880           if( pItem->zDatabase ){
881             sqlite3_str_appendall(pAccum, pItem->zDatabase);
882             sqlite3_str_append(pAccum, ".", 1);
883           }
884           sqlite3_str_appendall(pAccum, pItem->zName);
885         }else if( pItem->zAlias ){
886           sqlite3_str_appendall(pAccum, pItem->zAlias);
887         }else if( ALWAYS(pItem->pSelect) ){
888           sqlite3_str_appendf(pAccum, "SUBQUERY %u", pItem->pSelect->selId);
889         }
890         length = width = 0;
891         break;
892       }
893       default: {
894         assert( xtype==etINVALID );
895         return;
896       }
897     }/* End switch over the format type */
898     /*
899     ** The text of the conversion is pointed to by "bufpt" and is
900     ** "length" characters long.  The field width is "width".  Do
901     ** the output.  Both length and width are in bytes, not characters,
902     ** at this point.  If the "!" flag was present on string conversions
903     ** indicating that width and precision should be expressed in characters,
904     ** then the values have been translated prior to reaching this point.
905     */
906     width -= length;
907     if( width>0 ){
908       if( !flag_leftjustify ) sqlite3_str_appendchar(pAccum, width, ' ');
909       sqlite3_str_append(pAccum, bufpt, length);
910       if( flag_leftjustify ) sqlite3_str_appendchar(pAccum, width, ' ');
911     }else{
912       sqlite3_str_append(pAccum, bufpt, length);
913     }
914 
915     if( zExtra ){
916       sqlite3DbFree(pAccum->db, zExtra);
917       zExtra = 0;
918     }
919   }/* End for loop over the format string */
920 } /* End of function */
921 
922 
923 /*
924 ** The z string points to the first character of a token that is
925 ** associated with an error.  If db does not already have an error
926 ** byte offset recorded, try to compute the error byte offset for
927 ** z and set the error byte offset in db.
928 */
929 void sqlite3RecordErrorByteOffset(sqlite3 *db, const char *z){
930   const Parse *pParse;
931   const char *zText;
932   const char *zEnd;
933   assert( z!=0 );
934   if( NEVER(db==0) ) return;
935   if( db->errByteOffset!=(-2) ) return;
936   pParse = db->pParse;
937   if( NEVER(pParse==0) ) return;
938   zText =pParse->zTail;
939   if( NEVER(zText==0) ) return;
940   zEnd = &zText[strlen(zText)];
941   if( SQLITE_WITHIN(z,zText,zEnd) ){
942     db->errByteOffset = (int)(z-zText);
943   }
944 }
945 
946 /*
947 ** If pExpr has a byte offset for the start of a token, record that as
948 ** as the error offset.
949 */
950 void sqlite3RecordErrorOffsetOfExpr(sqlite3 *db, const Expr *pExpr){
951   while( pExpr && (ExprHasProperty(pExpr,EP_FromJoin) || pExpr->w.iOfst<=0) ){
952     pExpr = pExpr->pLeft;
953   }
954   if( pExpr==0 ) return;
955   db->errByteOffset = pExpr->w.iOfst;
956 }
957 
958 /*
959 ** Enlarge the memory allocation on a StrAccum object so that it is
960 ** able to accept at least N more bytes of text.
961 **
962 ** Return the number of bytes of text that StrAccum is able to accept
963 ** after the attempted enlargement.  The value returned might be zero.
964 */
965 int sqlite3StrAccumEnlarge(StrAccum *p, int N){
966   char *zNew;
967   assert( p->nChar+(i64)N >= p->nAlloc ); /* Only called if really needed */
968   if( p->accError ){
969     testcase(p->accError==SQLITE_TOOBIG);
970     testcase(p->accError==SQLITE_NOMEM);
971     return 0;
972   }
973   if( p->mxAlloc==0 ){
974     sqlite3StrAccumSetError(p, SQLITE_TOOBIG);
975     return p->nAlloc - p->nChar - 1;
976   }else{
977     char *zOld = isMalloced(p) ? p->zText : 0;
978     i64 szNew = p->nChar;
979     szNew += (sqlite3_int64)N + 1;
980     if( szNew+p->nChar<=p->mxAlloc ){
981       /* Force exponential buffer size growth as long as it does not overflow,
982       ** to avoid having to call this routine too often */
983       szNew += p->nChar;
984     }
985     if( szNew > p->mxAlloc ){
986       sqlite3_str_reset(p);
987       sqlite3StrAccumSetError(p, SQLITE_TOOBIG);
988       return 0;
989     }else{
990       p->nAlloc = (int)szNew;
991     }
992     if( p->db ){
993       zNew = sqlite3DbRealloc(p->db, zOld, p->nAlloc);
994     }else{
995       zNew = sqlite3Realloc(zOld, p->nAlloc);
996     }
997     if( zNew ){
998       assert( p->zText!=0 || p->nChar==0 );
999       if( !isMalloced(p) && p->nChar>0 ) memcpy(zNew, p->zText, p->nChar);
1000       p->zText = zNew;
1001       p->nAlloc = sqlite3DbMallocSize(p->db, zNew);
1002       p->printfFlags |= SQLITE_PRINTF_MALLOCED;
1003     }else{
1004       sqlite3_str_reset(p);
1005       sqlite3StrAccumSetError(p, SQLITE_NOMEM);
1006       return 0;
1007     }
1008   }
1009   return N;
1010 }
1011 
1012 /*
1013 ** Append N copies of character c to the given string buffer.
1014 */
1015 void sqlite3_str_appendchar(sqlite3_str *p, int N, char c){
1016   testcase( p->nChar + (i64)N > 0x7fffffff );
1017   if( p->nChar+(i64)N >= p->nAlloc && (N = sqlite3StrAccumEnlarge(p, N))<=0 ){
1018     return;
1019   }
1020   while( (N--)>0 ) p->zText[p->nChar++] = c;
1021 }
1022 
1023 /*
1024 ** The StrAccum "p" is not large enough to accept N new bytes of z[].
1025 ** So enlarge if first, then do the append.
1026 **
1027 ** This is a helper routine to sqlite3_str_append() that does special-case
1028 ** work (enlarging the buffer) using tail recursion, so that the
1029 ** sqlite3_str_append() routine can use fast calling semantics.
1030 */
1031 static void SQLITE_NOINLINE enlargeAndAppend(StrAccum *p, const char *z, int N){
1032   N = sqlite3StrAccumEnlarge(p, N);
1033   if( N>0 ){
1034     memcpy(&p->zText[p->nChar], z, N);
1035     p->nChar += N;
1036   }
1037 }
1038 
1039 /*
1040 ** Append N bytes of text from z to the StrAccum object.  Increase the
1041 ** size of the memory allocation for StrAccum if necessary.
1042 */
1043 void sqlite3_str_append(sqlite3_str *p, const char *z, int N){
1044   assert( z!=0 || N==0 );
1045   assert( p->zText!=0 || p->nChar==0 || p->accError );
1046   assert( N>=0 );
1047   assert( p->accError==0 || p->nAlloc==0 || p->mxAlloc==0 );
1048   if( p->nChar+N >= p->nAlloc ){
1049     enlargeAndAppend(p,z,N);
1050   }else if( N ){
1051     assert( p->zText );
1052     p->nChar += N;
1053     memcpy(&p->zText[p->nChar-N], z, N);
1054   }
1055 }
1056 
1057 /*
1058 ** Append the complete text of zero-terminated string z[] to the p string.
1059 */
1060 void sqlite3_str_appendall(sqlite3_str *p, const char *z){
1061   sqlite3_str_append(p, z, sqlite3Strlen30(z));
1062 }
1063 
1064 
1065 /*
1066 ** Finish off a string by making sure it is zero-terminated.
1067 ** Return a pointer to the resulting string.  Return a NULL
1068 ** pointer if any kind of error was encountered.
1069 */
1070 static SQLITE_NOINLINE char *strAccumFinishRealloc(StrAccum *p){
1071   char *zText;
1072   assert( p->mxAlloc>0 && !isMalloced(p) );
1073   zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
1074   if( zText ){
1075     memcpy(zText, p->zText, p->nChar+1);
1076     p->printfFlags |= SQLITE_PRINTF_MALLOCED;
1077   }else{
1078     sqlite3StrAccumSetError(p, SQLITE_NOMEM);
1079   }
1080   p->zText = zText;
1081   return zText;
1082 }
1083 char *sqlite3StrAccumFinish(StrAccum *p){
1084   if( p->zText ){
1085     p->zText[p->nChar] = 0;
1086     if( p->mxAlloc>0 && !isMalloced(p) ){
1087       return strAccumFinishRealloc(p);
1088     }
1089   }
1090   return p->zText;
1091 }
1092 
1093 /*
1094 ** Use the content of the StrAccum passed as the second argument
1095 ** as the result of an SQL function.
1096 */
1097 void sqlite3ResultStrAccum(sqlite3_context *pCtx, StrAccum *p){
1098   if( p->accError ){
1099     sqlite3_result_error_code(pCtx, p->accError);
1100     sqlite3_str_reset(p);
1101   }else if( isMalloced(p) ){
1102     sqlite3_result_text(pCtx, p->zText, p->nChar, SQLITE_DYNAMIC);
1103   }else{
1104     sqlite3_result_text(pCtx, "", 0, SQLITE_STATIC);
1105     sqlite3_str_reset(p);
1106   }
1107 }
1108 
1109 /*
1110 ** This singleton is an sqlite3_str object that is returned if
1111 ** sqlite3_malloc() fails to provide space for a real one.  This
1112 ** sqlite3_str object accepts no new text and always returns
1113 ** an SQLITE_NOMEM error.
1114 */
1115 static sqlite3_str sqlite3OomStr = {
1116    0, 0, 0, 0, 0, SQLITE_NOMEM, 0
1117 };
1118 
1119 /* Finalize a string created using sqlite3_str_new().
1120 */
1121 char *sqlite3_str_finish(sqlite3_str *p){
1122   char *z;
1123   if( p!=0 && p!=&sqlite3OomStr ){
1124     z = sqlite3StrAccumFinish(p);
1125     sqlite3_free(p);
1126   }else{
1127     z = 0;
1128   }
1129   return z;
1130 }
1131 
1132 /* Return any error code associated with p */
1133 int sqlite3_str_errcode(sqlite3_str *p){
1134   return p ? p->accError : SQLITE_NOMEM;
1135 }
1136 
1137 /* Return the current length of p in bytes */
1138 int sqlite3_str_length(sqlite3_str *p){
1139   return p ? p->nChar : 0;
1140 }
1141 
1142 /* Return the current value for p */
1143 char *sqlite3_str_value(sqlite3_str *p){
1144   if( p==0 || p->nChar==0 ) return 0;
1145   p->zText[p->nChar] = 0;
1146   return p->zText;
1147 }
1148 
1149 /*
1150 ** Reset an StrAccum string.  Reclaim all malloced memory.
1151 */
1152 void sqlite3_str_reset(StrAccum *p){
1153   if( isMalloced(p) ){
1154     sqlite3DbFree(p->db, p->zText);
1155     p->printfFlags &= ~SQLITE_PRINTF_MALLOCED;
1156   }
1157   p->nAlloc = 0;
1158   p->nChar = 0;
1159   p->zText = 0;
1160 }
1161 
1162 /*
1163 ** Initialize a string accumulator.
1164 **
1165 ** p:     The accumulator to be initialized.
1166 ** db:    Pointer to a database connection.  May be NULL.  Lookaside
1167 **        memory is used if not NULL. db->mallocFailed is set appropriately
1168 **        when not NULL.
1169 ** zBase: An initial buffer.  May be NULL in which case the initial buffer
1170 **        is malloced.
1171 ** n:     Size of zBase in bytes.  If total space requirements never exceed
1172 **        n then no memory allocations ever occur.
1173 ** mx:    Maximum number of bytes to accumulate.  If mx==0 then no memory
1174 **        allocations will ever occur.
1175 */
1176 void sqlite3StrAccumInit(StrAccum *p, sqlite3 *db, char *zBase, int n, int mx){
1177   p->zText = zBase;
1178   p->db = db;
1179   p->nAlloc = n;
1180   p->mxAlloc = mx;
1181   p->nChar = 0;
1182   p->accError = 0;
1183   p->printfFlags = 0;
1184 }
1185 
1186 /* Allocate and initialize a new dynamic string object */
1187 sqlite3_str *sqlite3_str_new(sqlite3 *db){
1188   sqlite3_str *p = sqlite3_malloc64(sizeof(*p));
1189   if( p ){
1190     sqlite3StrAccumInit(p, 0, 0, 0,
1191             db ? db->aLimit[SQLITE_LIMIT_LENGTH] : SQLITE_MAX_LENGTH);
1192   }else{
1193     p = &sqlite3OomStr;
1194   }
1195   return p;
1196 }
1197 
1198 /*
1199 ** Print into memory obtained from sqliteMalloc().  Use the internal
1200 ** %-conversion extensions.
1201 */
1202 char *sqlite3VMPrintf(sqlite3 *db, const char *zFormat, va_list ap){
1203   char *z;
1204   char zBase[SQLITE_PRINT_BUF_SIZE];
1205   StrAccum acc;
1206   assert( db!=0 );
1207   sqlite3StrAccumInit(&acc, db, zBase, sizeof(zBase),
1208                       db->aLimit[SQLITE_LIMIT_LENGTH]);
1209   acc.printfFlags = SQLITE_PRINTF_INTERNAL;
1210   sqlite3_str_vappendf(&acc, zFormat, ap);
1211   z = sqlite3StrAccumFinish(&acc);
1212   if( acc.accError==SQLITE_NOMEM ){
1213     sqlite3OomFault(db);
1214   }
1215   return z;
1216 }
1217 
1218 /*
1219 ** Print into memory obtained from sqliteMalloc().  Use the internal
1220 ** %-conversion extensions.
1221 */
1222 char *sqlite3MPrintf(sqlite3 *db, const char *zFormat, ...){
1223   va_list ap;
1224   char *z;
1225   va_start(ap, zFormat);
1226   z = sqlite3VMPrintf(db, zFormat, ap);
1227   va_end(ap);
1228   return z;
1229 }
1230 
1231 /*
1232 ** Print into memory obtained from sqlite3_malloc().  Omit the internal
1233 ** %-conversion extensions.
1234 */
1235 char *sqlite3_vmprintf(const char *zFormat, va_list ap){
1236   char *z;
1237   char zBase[SQLITE_PRINT_BUF_SIZE];
1238   StrAccum acc;
1239 
1240 #ifdef SQLITE_ENABLE_API_ARMOR
1241   if( zFormat==0 ){
1242     (void)SQLITE_MISUSE_BKPT;
1243     return 0;
1244   }
1245 #endif
1246 #ifndef SQLITE_OMIT_AUTOINIT
1247   if( sqlite3_initialize() ) return 0;
1248 #endif
1249   sqlite3StrAccumInit(&acc, 0, zBase, sizeof(zBase), SQLITE_MAX_LENGTH);
1250   sqlite3_str_vappendf(&acc, zFormat, ap);
1251   z = sqlite3StrAccumFinish(&acc);
1252   return z;
1253 }
1254 
1255 /*
1256 ** Print into memory obtained from sqlite3_malloc()().  Omit the internal
1257 ** %-conversion extensions.
1258 */
1259 char *sqlite3_mprintf(const char *zFormat, ...){
1260   va_list ap;
1261   char *z;
1262 #ifndef SQLITE_OMIT_AUTOINIT
1263   if( sqlite3_initialize() ) return 0;
1264 #endif
1265   va_start(ap, zFormat);
1266   z = sqlite3_vmprintf(zFormat, ap);
1267   va_end(ap);
1268   return z;
1269 }
1270 
1271 /*
1272 ** sqlite3_snprintf() works like snprintf() except that it ignores the
1273 ** current locale settings.  This is important for SQLite because we
1274 ** are not able to use a "," as the decimal point in place of "." as
1275 ** specified by some locales.
1276 **
1277 ** Oops:  The first two arguments of sqlite3_snprintf() are backwards
1278 ** from the snprintf() standard.  Unfortunately, it is too late to change
1279 ** this without breaking compatibility, so we just have to live with the
1280 ** mistake.
1281 **
1282 ** sqlite3_vsnprintf() is the varargs version.
1283 */
1284 char *sqlite3_vsnprintf(int n, char *zBuf, const char *zFormat, va_list ap){
1285   StrAccum acc;
1286   if( n<=0 ) return zBuf;
1287 #ifdef SQLITE_ENABLE_API_ARMOR
1288   if( zBuf==0 || zFormat==0 ) {
1289     (void)SQLITE_MISUSE_BKPT;
1290     if( zBuf ) zBuf[0] = 0;
1291     return zBuf;
1292   }
1293 #endif
1294   sqlite3StrAccumInit(&acc, 0, zBuf, n, 0);
1295   sqlite3_str_vappendf(&acc, zFormat, ap);
1296   zBuf[acc.nChar] = 0;
1297   return zBuf;
1298 }
1299 char *sqlite3_snprintf(int n, char *zBuf, const char *zFormat, ...){
1300   char *z;
1301   va_list ap;
1302   va_start(ap,zFormat);
1303   z = sqlite3_vsnprintf(n, zBuf, zFormat, ap);
1304   va_end(ap);
1305   return z;
1306 }
1307 
1308 /*
1309 ** This is the routine that actually formats the sqlite3_log() message.
1310 ** We house it in a separate routine from sqlite3_log() to avoid using
1311 ** stack space on small-stack systems when logging is disabled.
1312 **
1313 ** sqlite3_log() must render into a static buffer.  It cannot dynamically
1314 ** allocate memory because it might be called while the memory allocator
1315 ** mutex is held.
1316 **
1317 ** sqlite3_str_vappendf() might ask for *temporary* memory allocations for
1318 ** certain format characters (%q) or for very large precisions or widths.
1319 ** Care must be taken that any sqlite3_log() calls that occur while the
1320 ** memory mutex is held do not use these mechanisms.
1321 */
1322 static void renderLogMsg(int iErrCode, const char *zFormat, va_list ap){
1323   StrAccum acc;                          /* String accumulator */
1324   char zMsg[SQLITE_PRINT_BUF_SIZE*3];    /* Complete log message */
1325 
1326   sqlite3StrAccumInit(&acc, 0, zMsg, sizeof(zMsg), 0);
1327   sqlite3_str_vappendf(&acc, zFormat, ap);
1328   sqlite3GlobalConfig.xLog(sqlite3GlobalConfig.pLogArg, iErrCode,
1329                            sqlite3StrAccumFinish(&acc));
1330 }
1331 
1332 /*
1333 ** Format and write a message to the log if logging is enabled.
1334 */
1335 void sqlite3_log(int iErrCode, const char *zFormat, ...){
1336   va_list ap;                             /* Vararg list */
1337   if( sqlite3GlobalConfig.xLog ){
1338     va_start(ap, zFormat);
1339     renderLogMsg(iErrCode, zFormat, ap);
1340     va_end(ap);
1341   }
1342 }
1343 
1344 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
1345 /*
1346 ** A version of printf() that understands %lld.  Used for debugging.
1347 ** The printf() built into some versions of windows does not understand %lld
1348 ** and segfaults if you give it a long long int.
1349 */
1350 void sqlite3DebugPrintf(const char *zFormat, ...){
1351   va_list ap;
1352   StrAccum acc;
1353   char zBuf[SQLITE_PRINT_BUF_SIZE*10];
1354   sqlite3StrAccumInit(&acc, 0, zBuf, sizeof(zBuf), 0);
1355   va_start(ap,zFormat);
1356   sqlite3_str_vappendf(&acc, zFormat, ap);
1357   va_end(ap);
1358   sqlite3StrAccumFinish(&acc);
1359 #ifdef SQLITE_OS_TRACE_PROC
1360   {
1361     extern void SQLITE_OS_TRACE_PROC(const char *zBuf, int nBuf);
1362     SQLITE_OS_TRACE_PROC(zBuf, sizeof(zBuf));
1363   }
1364 #else
1365   fprintf(stdout,"%s", zBuf);
1366   fflush(stdout);
1367 #endif
1368 }
1369 #endif
1370 
1371 
1372 /*
1373 ** variable-argument wrapper around sqlite3_str_vappendf(). The bFlags argument
1374 ** can contain the bit SQLITE_PRINTF_INTERNAL enable internal formats.
1375 */
1376 void sqlite3_str_appendf(StrAccum *p, const char *zFormat, ...){
1377   va_list ap;
1378   va_start(ap,zFormat);
1379   sqlite3_str_vappendf(p, zFormat, ap);
1380   va_end(ap);
1381 }
1382