xref: /sqlite-3.40.0/src/printf.c (revision dd6c33d3)
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 etSRCLIST    12 /* a pointer to a SrcList */
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, etSRCLIST,    0,  0 },
99   {  'r', 10, 1, etORDINAL,    0,  0 },
100 };
101 
102 /* Floating point constants used for rounding */
103 static const double arRound[] = {
104   5.0e-01, 5.0e-02, 5.0e-03, 5.0e-04, 5.0e-05,
105   5.0e-06, 5.0e-07, 5.0e-08, 5.0e-09, 5.0e-10,
106 };
107 
108 /*
109 ** If SQLITE_OMIT_FLOATING_POINT is defined, then none of the floating point
110 ** conversions will work.
111 */
112 #ifndef SQLITE_OMIT_FLOATING_POINT
113 /*
114 ** "*val" is a double such that 0.1 <= *val < 10.0
115 ** Return the ascii code for the leading digit of *val, then
116 ** multiply "*val" by 10.0 to renormalize.
117 **
118 ** Example:
119 **     input:     *val = 3.14159
120 **     output:    *val = 1.4159    function return = '3'
121 **
122 ** The counter *cnt is incremented each time.  After counter exceeds
123 ** 16 (the number of significant digits in a 64-bit float) '0' is
124 ** always returned.
125 */
126 static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
127   int digit;
128   LONGDOUBLE_TYPE d;
129   if( (*cnt)<=0 ) return '0';
130   (*cnt)--;
131   digit = (int)*val;
132   d = digit;
133   digit += '0';
134   *val = (*val - d)*10.0;
135   return (char)digit;
136 }
137 #endif /* SQLITE_OMIT_FLOATING_POINT */
138 
139 /*
140 ** Set the StrAccum object to an error mode.
141 */
142 static void setStrAccumError(StrAccum *p, u8 eError){
143   assert( eError==SQLITE_NOMEM || eError==SQLITE_TOOBIG );
144   p->accError = eError;
145   if( p->mxAlloc ) sqlite3_str_reset(p);
146   if( eError==SQLITE_TOOBIG ) sqlite3ErrorToParser(p->db, eError);
147 }
148 
149 /*
150 ** Extra argument values from a PrintfArguments object
151 */
152 static sqlite3_int64 getIntArg(PrintfArguments *p){
153   if( p->nArg<=p->nUsed ) return 0;
154   return sqlite3_value_int64(p->apArg[p->nUsed++]);
155 }
156 static double getDoubleArg(PrintfArguments *p){
157   if( p->nArg<=p->nUsed ) return 0.0;
158   return sqlite3_value_double(p->apArg[p->nUsed++]);
159 }
160 static char *getTextArg(PrintfArguments *p){
161   if( p->nArg<=p->nUsed ) return 0;
162   return (char*)sqlite3_value_text(p->apArg[p->nUsed++]);
163 }
164 
165 /*
166 ** Allocate memory for a temporary buffer needed for printf rendering.
167 **
168 ** If the requested size of the temp buffer is larger than the size
169 ** of the output buffer in pAccum, then cause an SQLITE_TOOBIG error.
170 ** Do the size check before the memory allocation to prevent rogue
171 ** SQL from requesting large allocations using the precision or width
172 ** field of the printf() function.
173 */
174 static char *printfTempBuf(sqlite3_str *pAccum, sqlite3_int64 n){
175   char *z;
176   if( pAccum->accError ) return 0;
177   if( n>pAccum->nAlloc && n>pAccum->mxAlloc ){
178     setStrAccumError(pAccum, SQLITE_TOOBIG);
179     return 0;
180   }
181   z = sqlite3DbMallocRaw(pAccum->db, n);
182   if( z==0 ){
183     setStrAccumError(pAccum, SQLITE_NOMEM);
184   }
185   return z;
186 }
187 
188 /*
189 ** On machines with a small stack size, you can redefine the
190 ** SQLITE_PRINT_BUF_SIZE to be something smaller, if desired.
191 */
192 #ifndef SQLITE_PRINT_BUF_SIZE
193 # define SQLITE_PRINT_BUF_SIZE 70
194 #endif
195 #define etBUFSIZE SQLITE_PRINT_BUF_SIZE  /* Size of the output buffer */
196 
197 /*
198 ** Hard limit on the precision of floating-point conversions.
199 */
200 #ifndef SQLITE_PRINTF_PRECISION_LIMIT
201 # define SQLITE_FP_PRECISION_LIMIT 100000000
202 #endif
203 
204 /*
205 ** Render a string given by "fmt" into the StrAccum object.
206 */
207 void sqlite3_str_vappendf(
208   sqlite3_str *pAccum,       /* Accumulate results here */
209   const char *fmt,           /* Format string */
210   va_list ap                 /* arguments */
211 ){
212   int c;                     /* Next character in the format string */
213   char *bufpt;               /* Pointer to the conversion buffer */
214   int precision;             /* Precision of the current field */
215   int length;                /* Length of the field */
216   int idx;                   /* A general purpose loop counter */
217   int width;                 /* Width of the current field */
218   etByte flag_leftjustify;   /* True if "-" flag is present */
219   etByte flag_prefix;        /* '+' or ' ' or 0 for prefix */
220   etByte flag_alternateform; /* True if "#" flag is present */
221   etByte flag_altform2;      /* True if "!" flag is present */
222   etByte flag_zeropad;       /* True if field width constant starts with zero */
223   etByte flag_long;          /* 1 for the "l" flag, 2 for "ll", 0 by default */
224   etByte done;               /* Loop termination flag */
225   etByte cThousand;          /* Thousands separator for %d and %u */
226   etByte xtype = etINVALID;  /* Conversion paradigm */
227   u8 bArgList;               /* True for SQLITE_PRINTF_SQLFUNC */
228   char prefix;               /* Prefix character.  "+" or "-" or " " or '\0'. */
229   sqlite_uint64 longvalue;   /* Value for integer types */
230   LONGDOUBLE_TYPE realvalue; /* Value for real types */
231   const et_info *infop;      /* Pointer to the appropriate info structure */
232   char *zOut;                /* Rendering buffer */
233   int nOut;                  /* Size of the rendering buffer */
234   char *zExtra = 0;          /* Malloced memory used by some conversion */
235 #ifndef SQLITE_OMIT_FLOATING_POINT
236   int  exp, e2;              /* exponent of real numbers */
237   int nsd;                   /* Number of significant digits returned */
238   double rounder;            /* Used for rounding floating point values */
239   etByte flag_dp;            /* True if decimal point should be shown */
240   etByte flag_rtz;           /* True if trailing zeros should be removed */
241 #endif
242   PrintfArguments *pArgList = 0; /* Arguments for SQLITE_PRINTF_SQLFUNC */
243   char buf[etBUFSIZE];       /* Conversion buffer */
244 
245   /* pAccum never starts out with an empty buffer that was obtained from
246   ** malloc().  This precondition is required by the mprintf("%z...")
247   ** optimization. */
248   assert( pAccum->nChar>0 || (pAccum->printfFlags&SQLITE_PRINTF_MALLOCED)==0 );
249 
250   bufpt = 0;
251   if( (pAccum->printfFlags & SQLITE_PRINTF_SQLFUNC)!=0 ){
252     pArgList = va_arg(ap, PrintfArguments*);
253     bArgList = 1;
254   }else{
255     bArgList = 0;
256   }
257   for(; (c=(*fmt))!=0; ++fmt){
258     if( c!='%' ){
259       bufpt = (char *)fmt;
260 #if HAVE_STRCHRNUL
261       fmt = strchrnul(fmt, '%');
262 #else
263       do{ fmt++; }while( *fmt && *fmt != '%' );
264 #endif
265       sqlite3_str_append(pAccum, bufpt, (int)(fmt - bufpt));
266       if( *fmt==0 ) break;
267     }
268     if( (c=(*++fmt))==0 ){
269       sqlite3_str_append(pAccum, "%", 1);
270       break;
271     }
272     /* Find out what flags are present */
273     flag_leftjustify = flag_prefix = cThousand =
274      flag_alternateform = flag_altform2 = flag_zeropad = 0;
275     done = 0;
276     width = 0;
277     flag_long = 0;
278     precision = -1;
279     do{
280       switch( c ){
281         case '-':   flag_leftjustify = 1;     break;
282         case '+':   flag_prefix = '+';        break;
283         case ' ':   flag_prefix = ' ';        break;
284         case '#':   flag_alternateform = 1;   break;
285         case '!':   flag_altform2 = 1;        break;
286         case '0':   flag_zeropad = 1;         break;
287         case ',':   cThousand = ',';          break;
288         default:    done = 1;                 break;
289         case 'l': {
290           flag_long = 1;
291           c = *++fmt;
292           if( c=='l' ){
293             c = *++fmt;
294             flag_long = 2;
295           }
296           done = 1;
297           break;
298         }
299         case '1': case '2': case '3': case '4': case '5':
300         case '6': case '7': case '8': case '9': {
301           unsigned wx = c - '0';
302           while( (c = *++fmt)>='0' && c<='9' ){
303             wx = wx*10 + c - '0';
304           }
305           testcase( wx>0x7fffffff );
306           width = wx & 0x7fffffff;
307 #ifdef SQLITE_PRINTF_PRECISION_LIMIT
308           if( width>SQLITE_PRINTF_PRECISION_LIMIT ){
309             width = SQLITE_PRINTF_PRECISION_LIMIT;
310           }
311 #endif
312           if( c!='.' && c!='l' ){
313             done = 1;
314           }else{
315             fmt--;
316           }
317           break;
318         }
319         case '*': {
320           if( bArgList ){
321             width = (int)getIntArg(pArgList);
322           }else{
323             width = va_arg(ap,int);
324           }
325           if( width<0 ){
326             flag_leftjustify = 1;
327             width = width >= -2147483647 ? -width : 0;
328           }
329 #ifdef SQLITE_PRINTF_PRECISION_LIMIT
330           if( width>SQLITE_PRINTF_PRECISION_LIMIT ){
331             width = SQLITE_PRINTF_PRECISION_LIMIT;
332           }
333 #endif
334           if( (c = fmt[1])!='.' && c!='l' ){
335             c = *++fmt;
336             done = 1;
337           }
338           break;
339         }
340         case '.': {
341           c = *++fmt;
342           if( c=='*' ){
343             if( bArgList ){
344               precision = (int)getIntArg(pArgList);
345             }else{
346               precision = va_arg(ap,int);
347             }
348             if( precision<0 ){
349               precision = precision >= -2147483647 ? -precision : -1;
350             }
351             c = *++fmt;
352           }else{
353             unsigned px = 0;
354             while( c>='0' && c<='9' ){
355               px = px*10 + c - '0';
356               c = *++fmt;
357             }
358             testcase( px>0x7fffffff );
359             precision = px & 0x7fffffff;
360           }
361 #ifdef SQLITE_PRINTF_PRECISION_LIMIT
362           if( precision>SQLITE_PRINTF_PRECISION_LIMIT ){
363             precision = SQLITE_PRINTF_PRECISION_LIMIT;
364           }
365 #endif
366           if( c=='l' ){
367             --fmt;
368           }else{
369             done = 1;
370           }
371           break;
372         }
373       }
374     }while( !done && (c=(*++fmt))!=0 );
375 
376     /* Fetch the info entry for the field */
377     infop = &fmtinfo[0];
378     xtype = etINVALID;
379     for(idx=0; idx<ArraySize(fmtinfo); idx++){
380       if( c==fmtinfo[idx].fmttype ){
381         infop = &fmtinfo[idx];
382         xtype = infop->type;
383         break;
384       }
385     }
386 
387     /*
388     ** At this point, variables are initialized as follows:
389     **
390     **   flag_alternateform          TRUE if a '#' is present.
391     **   flag_altform2               TRUE if a '!' is present.
392     **   flag_prefix                 '+' or ' ' or zero
393     **   flag_leftjustify            TRUE if a '-' is present or if the
394     **                               field width was negative.
395     **   flag_zeropad                TRUE if the width began with 0.
396     **   flag_long                   1 for "l", 2 for "ll"
397     **   width                       The specified field width.  This is
398     **                               always non-negative.  Zero is the default.
399     **   precision                   The specified precision.  The default
400     **                               is -1.
401     **   xtype                       The class of the conversion.
402     **   infop                       Pointer to the appropriate info struct.
403     */
404     switch( xtype ){
405       case etPOINTER:
406         flag_long = sizeof(char*)==sizeof(i64) ? 2 :
407                      sizeof(char*)==sizeof(long int) ? 1 : 0;
408         /* Fall through into the next case */
409       case etORDINAL:
410       case etRADIX:
411         cThousand = 0;
412         /* Fall through into the next case */
413       case etDECIMAL:
414         if( infop->flags & FLAG_SIGNED ){
415           i64 v;
416           if( bArgList ){
417             v = getIntArg(pArgList);
418           }else if( flag_long ){
419             if( flag_long==2 ){
420               v = va_arg(ap,i64) ;
421             }else{
422               v = va_arg(ap,long int);
423             }
424           }else{
425             v = va_arg(ap,int);
426           }
427           if( v<0 ){
428             if( v==SMALLEST_INT64 ){
429               longvalue = ((u64)1)<<63;
430             }else{
431               longvalue = -v;
432             }
433             prefix = '-';
434           }else{
435             longvalue = v;
436             prefix = flag_prefix;
437           }
438         }else{
439           if( bArgList ){
440             longvalue = (u64)getIntArg(pArgList);
441           }else if( flag_long ){
442             if( flag_long==2 ){
443               longvalue = va_arg(ap,u64);
444             }else{
445               longvalue = va_arg(ap,unsigned long int);
446             }
447           }else{
448             longvalue = va_arg(ap,unsigned int);
449           }
450           prefix = 0;
451         }
452         if( longvalue==0 ) flag_alternateform = 0;
453         if( flag_zeropad && precision<width-(prefix!=0) ){
454           precision = width-(prefix!=0);
455         }
456         if( precision<etBUFSIZE-10-etBUFSIZE/3 ){
457           nOut = etBUFSIZE;
458           zOut = buf;
459         }else{
460           u64 n;
461           n = (u64)precision + 10;
462           if( cThousand ) n += precision/3;
463           zOut = zExtra = printfTempBuf(pAccum, n);
464           if( zOut==0 ) return;
465           nOut = (int)n;
466         }
467         bufpt = &zOut[nOut-1];
468         if( xtype==etORDINAL ){
469           static const char zOrd[] = "thstndrd";
470           int x = (int)(longvalue % 10);
471           if( x>=4 || (longvalue/10)%10==1 ){
472             x = 0;
473           }
474           *(--bufpt) = zOrd[x*2+1];
475           *(--bufpt) = zOrd[x*2];
476         }
477         {
478           const char *cset = &aDigits[infop->charset];
479           u8 base = infop->base;
480           do{                                           /* Convert to ascii */
481             *(--bufpt) = cset[longvalue%base];
482             longvalue = longvalue/base;
483           }while( longvalue>0 );
484         }
485         length = (int)(&zOut[nOut-1]-bufpt);
486         while( precision>length ){
487           *(--bufpt) = '0';                             /* Zero pad */
488           length++;
489         }
490         if( cThousand ){
491           int nn = (length - 1)/3;  /* Number of "," to insert */
492           int ix = (length - 1)%3 + 1;
493           bufpt -= nn;
494           for(idx=0; nn>0; idx++){
495             bufpt[idx] = bufpt[idx+nn];
496             ix--;
497             if( ix==0 ){
498               bufpt[++idx] = cThousand;
499               nn--;
500               ix = 3;
501             }
502           }
503         }
504         if( prefix ) *(--bufpt) = prefix;               /* Add sign */
505         if( flag_alternateform && infop->prefix ){      /* Add "0" or "0x" */
506           const char *pre;
507           char x;
508           pre = &aPrefix[infop->prefix];
509           for(; (x=(*pre))!=0; pre++) *(--bufpt) = x;
510         }
511         length = (int)(&zOut[nOut-1]-bufpt);
512         break;
513       case etFLOAT:
514       case etEXP:
515       case etGENERIC:
516         if( bArgList ){
517           realvalue = getDoubleArg(pArgList);
518         }else{
519           realvalue = va_arg(ap,double);
520         }
521 #ifdef SQLITE_OMIT_FLOATING_POINT
522         length = 0;
523 #else
524         if( precision<0 ) precision = 6;         /* Set default precision */
525 #ifdef SQLITE_FP_PRECISION_LIMIT
526         if( precision>SQLITE_FP_PRECISION_LIMIT ){
527           precision = SQLITE_FP_PRECISION_LIMIT;
528         }
529 #endif
530         if( realvalue<0.0 ){
531           realvalue = -realvalue;
532           prefix = '-';
533         }else{
534           prefix = flag_prefix;
535         }
536         if( xtype==etGENERIC && precision>0 ) precision--;
537         testcase( precision>0xfff );
538         idx = precision & 0xfff;
539         rounder = arRound[idx%10];
540         while( idx>=10 ){ rounder *= 1.0e-10; idx -= 10; }
541         if( xtype==etFLOAT ){
542           double rx = (double)realvalue;
543           sqlite3_uint64 u;
544           int ex;
545           memcpy(&u, &rx, sizeof(u));
546           ex = -1023 + (int)((u>>52)&0x7ff);
547           if( precision+(ex/3) < 15 ) rounder += realvalue*3e-16;
548           realvalue += rounder;
549         }
550         /* Normalize realvalue to within 10.0 > realvalue >= 1.0 */
551         exp = 0;
552         if( sqlite3IsNaN((double)realvalue) ){
553           bufpt = "NaN";
554           length = 3;
555           break;
556         }
557         if( realvalue>0.0 ){
558           LONGDOUBLE_TYPE scale = 1.0;
559           while( realvalue>=1e100*scale && exp<=350 ){ scale *= 1e100;exp+=100;}
560           while( realvalue>=1e10*scale && exp<=350 ){ scale *= 1e10; exp+=10; }
561           while( realvalue>=10.0*scale && exp<=350 ){ scale *= 10.0; exp++; }
562           realvalue /= scale;
563           while( realvalue<1e-8 ){ realvalue *= 1e8; exp-=8; }
564           while( realvalue<1.0 ){ realvalue *= 10.0; exp--; }
565           if( exp>350 ){
566             bufpt = buf;
567             buf[0] = prefix;
568             memcpy(buf+(prefix!=0),"Inf",4);
569             length = 3+(prefix!=0);
570             break;
571           }
572         }
573         bufpt = buf;
574         /*
575         ** If the field type is etGENERIC, then convert to either etEXP
576         ** or etFLOAT, as appropriate.
577         */
578         if( xtype!=etFLOAT ){
579           realvalue += rounder;
580           if( realvalue>=10.0 ){ realvalue *= 0.1; exp++; }
581         }
582         if( xtype==etGENERIC ){
583           flag_rtz = !flag_alternateform;
584           if( exp<-4 || exp>precision ){
585             xtype = etEXP;
586           }else{
587             precision = precision - exp;
588             xtype = etFLOAT;
589           }
590         }else{
591           flag_rtz = flag_altform2;
592         }
593         if( xtype==etEXP ){
594           e2 = 0;
595         }else{
596           e2 = exp;
597         }
598         {
599           i64 szBufNeeded;           /* Size of a temporary buffer needed */
600           szBufNeeded = MAX(e2,0)+(i64)precision+(i64)width+15;
601           if( szBufNeeded > etBUFSIZE ){
602             bufpt = zExtra = printfTempBuf(pAccum, szBufNeeded);
603             if( bufpt==0 ) return;
604           }
605         }
606         zOut = bufpt;
607         nsd = 16 + flag_altform2*10;
608         flag_dp = (precision>0 ?1:0) | flag_alternateform | flag_altform2;
609         /* The sign in front of the number */
610         if( prefix ){
611           *(bufpt++) = prefix;
612         }
613         /* Digits prior to the decimal point */
614         if( e2<0 ){
615           *(bufpt++) = '0';
616         }else{
617           for(; e2>=0; e2--){
618             *(bufpt++) = et_getdigit(&realvalue,&nsd);
619           }
620         }
621         /* The decimal point */
622         if( flag_dp ){
623           *(bufpt++) = '.';
624         }
625         /* "0" digits after the decimal point but before the first
626         ** significant digit of the number */
627         for(e2++; e2<0; precision--, e2++){
628           assert( precision>0 );
629           *(bufpt++) = '0';
630         }
631         /* Significant digits after the decimal point */
632         while( (precision--)>0 ){
633           *(bufpt++) = et_getdigit(&realvalue,&nsd);
634         }
635         /* Remove trailing zeros and the "." if no digits follow the "." */
636         if( flag_rtz && flag_dp ){
637           while( bufpt[-1]=='0' ) *(--bufpt) = 0;
638           assert( bufpt>zOut );
639           if( bufpt[-1]=='.' ){
640             if( flag_altform2 ){
641               *(bufpt++) = '0';
642             }else{
643               *(--bufpt) = 0;
644             }
645           }
646         }
647         /* Add the "eNNN" suffix */
648         if( xtype==etEXP ){
649           *(bufpt++) = aDigits[infop->charset];
650           if( exp<0 ){
651             *(bufpt++) = '-'; exp = -exp;
652           }else{
653             *(bufpt++) = '+';
654           }
655           if( exp>=100 ){
656             *(bufpt++) = (char)((exp/100)+'0');        /* 100's digit */
657             exp %= 100;
658           }
659           *(bufpt++) = (char)(exp/10+'0');             /* 10's digit */
660           *(bufpt++) = (char)(exp%10+'0');             /* 1's digit */
661         }
662         *bufpt = 0;
663 
664         /* The converted number is in buf[] and zero terminated. Output it.
665         ** Note that the number is in the usual order, not reversed as with
666         ** integer conversions. */
667         length = (int)(bufpt-zOut);
668         bufpt = zOut;
669 
670         /* Special case:  Add leading zeros if the flag_zeropad flag is
671         ** set and we are not left justified */
672         if( flag_zeropad && !flag_leftjustify && length < width){
673           int i;
674           int nPad = width - length;
675           for(i=width; i>=nPad; i--){
676             bufpt[i] = bufpt[i-nPad];
677           }
678           i = prefix!=0;
679           while( nPad-- ) bufpt[i++] = '0';
680           length = width;
681         }
682 #endif /* !defined(SQLITE_OMIT_FLOATING_POINT) */
683         break;
684       case etSIZE:
685         if( !bArgList ){
686           *(va_arg(ap,int*)) = pAccum->nChar;
687         }
688         length = width = 0;
689         break;
690       case etPERCENT:
691         buf[0] = '%';
692         bufpt = buf;
693         length = 1;
694         break;
695       case etCHARX:
696         if( bArgList ){
697           bufpt = getTextArg(pArgList);
698           length = 1;
699           if( bufpt ){
700             buf[0] = c = *(bufpt++);
701             if( (c&0xc0)==0xc0 ){
702               while( length<4 && (bufpt[0]&0xc0)==0x80 ){
703                 buf[length++] = *(bufpt++);
704               }
705             }
706           }else{
707             buf[0] = 0;
708           }
709         }else{
710           unsigned int ch = va_arg(ap,unsigned int);
711           if( ch<0x00080 ){
712             buf[0] = ch & 0xff;
713             length = 1;
714           }else if( ch<0x00800 ){
715             buf[0] = 0xc0 + (u8)((ch>>6)&0x1f);
716             buf[1] = 0x80 + (u8)(ch & 0x3f);
717             length = 2;
718           }else if( ch<0x10000 ){
719             buf[0] = 0xe0 + (u8)((ch>>12)&0x0f);
720             buf[1] = 0x80 + (u8)((ch>>6) & 0x3f);
721             buf[2] = 0x80 + (u8)(ch & 0x3f);
722             length = 3;
723           }else{
724             buf[0] = 0xf0 + (u8)((ch>>18) & 0x07);
725             buf[1] = 0x80 + (u8)((ch>>12) & 0x3f);
726             buf[2] = 0x80 + (u8)((ch>>6) & 0x3f);
727             buf[3] = 0x80 + (u8)(ch & 0x3f);
728             length = 4;
729           }
730         }
731         if( precision>1 ){
732           width -= precision-1;
733           if( width>1 && !flag_leftjustify ){
734             sqlite3_str_appendchar(pAccum, width-1, ' ');
735             width = 0;
736           }
737           while( precision-- > 1 ){
738             sqlite3_str_append(pAccum, buf, length);
739           }
740         }
741         bufpt = buf;
742         flag_altform2 = 1;
743         goto adjust_width_for_utf8;
744       case etSTRING:
745       case etDYNSTRING:
746         if( bArgList ){
747           bufpt = getTextArg(pArgList);
748           xtype = etSTRING;
749         }else{
750           bufpt = va_arg(ap,char*);
751         }
752         if( bufpt==0 ){
753           bufpt = "";
754         }else if( xtype==etDYNSTRING ){
755           if( pAccum->nChar==0
756            && pAccum->mxAlloc
757            && width==0
758            && precision<0
759            && pAccum->accError==0
760           ){
761             /* Special optimization for sqlite3_mprintf("%z..."):
762             ** Extend an existing memory allocation rather than creating
763             ** a new one. */
764             assert( (pAccum->printfFlags&SQLITE_PRINTF_MALLOCED)==0 );
765             pAccum->zText = bufpt;
766             pAccum->nAlloc = sqlite3DbMallocSize(pAccum->db, bufpt);
767             pAccum->nChar = 0x7fffffff & (int)strlen(bufpt);
768             pAccum->printfFlags |= SQLITE_PRINTF_MALLOCED;
769             length = 0;
770             break;
771           }
772           zExtra = bufpt;
773         }
774         if( precision>=0 ){
775           if( flag_altform2 ){
776             /* Set length to the number of bytes needed in order to display
777             ** precision characters */
778             unsigned char *z = (unsigned char*)bufpt;
779             while( precision-- > 0 && z[0] ){
780               SQLITE_SKIP_UTF8(z);
781             }
782             length = (int)(z - (unsigned char*)bufpt);
783           }else{
784             for(length=0; length<precision && bufpt[length]; length++){}
785           }
786         }else{
787           length = 0x7fffffff & (int)strlen(bufpt);
788         }
789       adjust_width_for_utf8:
790         if( flag_altform2 && width>0 ){
791           /* Adjust width to account for extra bytes in UTF-8 characters */
792           int ii = length - 1;
793           while( ii>=0 ) if( (bufpt[ii--] & 0xc0)==0x80 ) width++;
794         }
795         break;
796       case etSQLESCAPE:           /* %q: Escape ' characters */
797       case etSQLESCAPE2:          /* %Q: Escape ' and enclose in '...' */
798       case etSQLESCAPE3: {        /* %w: Escape " characters */
799         int i, j, k, n, isnull;
800         int needQuote;
801         char ch;
802         char q = ((xtype==etSQLESCAPE3)?'"':'\'');   /* Quote character */
803         char *escarg;
804 
805         if( bArgList ){
806           escarg = getTextArg(pArgList);
807         }else{
808           escarg = va_arg(ap,char*);
809         }
810         isnull = escarg==0;
811         if( isnull ) escarg = (xtype==etSQLESCAPE2 ? "NULL" : "(NULL)");
812         /* For %q, %Q, and %w, the precision is the number of byte (or
813         ** characters if the ! flags is present) to use from the input.
814         ** Because of the extra quoting characters inserted, the number
815         ** of output characters may be larger than the precision.
816         */
817         k = precision;
818         for(i=n=0; k!=0 && (ch=escarg[i])!=0; i++, k--){
819           if( ch==q )  n++;
820           if( flag_altform2 && (ch&0xc0)==0xc0 ){
821             while( (escarg[i+1]&0xc0)==0x80 ){ i++; }
822           }
823         }
824         needQuote = !isnull && xtype==etSQLESCAPE2;
825         n += i + 3;
826         if( n>etBUFSIZE ){
827           bufpt = zExtra = printfTempBuf(pAccum, n);
828           if( bufpt==0 ) return;
829         }else{
830           bufpt = buf;
831         }
832         j = 0;
833         if( needQuote ) bufpt[j++] = q;
834         k = i;
835         for(i=0; i<k; i++){
836           bufpt[j++] = ch = escarg[i];
837           if( ch==q ) bufpt[j++] = ch;
838         }
839         if( needQuote ) bufpt[j++] = q;
840         bufpt[j] = 0;
841         length = j;
842         goto adjust_width_for_utf8;
843       }
844       case etTOKEN: {
845         Token *pToken;
846         if( (pAccum->printfFlags & SQLITE_PRINTF_INTERNAL)==0 ) return;
847         pToken = va_arg(ap, Token*);
848         assert( bArgList==0 );
849         if( pToken && pToken->n ){
850           sqlite3_str_append(pAccum, (const char*)pToken->z, pToken->n);
851         }
852         length = width = 0;
853         break;
854       }
855       case etSRCLIST: {
856         SrcList *pSrc;
857         int k;
858         struct SrcList_item *pItem;
859         if( (pAccum->printfFlags & SQLITE_PRINTF_INTERNAL)==0 ) return;
860         pSrc = va_arg(ap, SrcList*);
861         k = va_arg(ap, int);
862         pItem = &pSrc->a[k];
863         assert( bArgList==0 );
864         assert( k>=0 && k<pSrc->nSrc );
865         if( pItem->zDatabase ){
866           sqlite3_str_appendall(pAccum, pItem->zDatabase);
867           sqlite3_str_append(pAccum, ".", 1);
868         }
869         sqlite3_str_appendall(pAccum, pItem->zName);
870         length = width = 0;
871         break;
872       }
873       default: {
874         assert( xtype==etINVALID );
875         return;
876       }
877     }/* End switch over the format type */
878     /*
879     ** The text of the conversion is pointed to by "bufpt" and is
880     ** "length" characters long.  The field width is "width".  Do
881     ** the output.  Both length and width are in bytes, not characters,
882     ** at this point.  If the "!" flag was present on string conversions
883     ** indicating that width and precision should be expressed in characters,
884     ** then the values have been translated prior to reaching this point.
885     */
886     width -= length;
887     if( width>0 ){
888       if( !flag_leftjustify ) sqlite3_str_appendchar(pAccum, width, ' ');
889       sqlite3_str_append(pAccum, bufpt, length);
890       if( flag_leftjustify ) sqlite3_str_appendchar(pAccum, width, ' ');
891     }else{
892       sqlite3_str_append(pAccum, bufpt, length);
893     }
894 
895     if( zExtra ){
896       sqlite3DbFree(pAccum->db, zExtra);
897       zExtra = 0;
898     }
899   }/* End for loop over the format string */
900 } /* End of function */
901 
902 /*
903 ** Enlarge the memory allocation on a StrAccum object so that it is
904 ** able to accept at least N more bytes of text.
905 **
906 ** Return the number of bytes of text that StrAccum is able to accept
907 ** after the attempted enlargement.  The value returned might be zero.
908 */
909 static int sqlite3StrAccumEnlarge(StrAccum *p, int N){
910   char *zNew;
911   assert( p->nChar+(i64)N >= p->nAlloc ); /* Only called if really needed */
912   if( p->accError ){
913     testcase(p->accError==SQLITE_TOOBIG);
914     testcase(p->accError==SQLITE_NOMEM);
915     return 0;
916   }
917   if( p->mxAlloc==0 ){
918     setStrAccumError(p, SQLITE_TOOBIG);
919     return p->nAlloc - p->nChar - 1;
920   }else{
921     char *zOld = isMalloced(p) ? p->zText : 0;
922     i64 szNew = p->nChar;
923     szNew += N + 1;
924     if( szNew+p->nChar<=p->mxAlloc ){
925       /* Force exponential buffer size growth as long as it does not overflow,
926       ** to avoid having to call this routine too often */
927       szNew += p->nChar;
928     }
929     if( szNew > p->mxAlloc ){
930       sqlite3_str_reset(p);
931       setStrAccumError(p, SQLITE_TOOBIG);
932       return 0;
933     }else{
934       p->nAlloc = (int)szNew;
935     }
936     if( p->db ){
937       zNew = sqlite3DbRealloc(p->db, zOld, p->nAlloc);
938     }else{
939       zNew = sqlite3Realloc(zOld, p->nAlloc);
940     }
941     if( zNew ){
942       assert( p->zText!=0 || p->nChar==0 );
943       if( !isMalloced(p) && p->nChar>0 ) memcpy(zNew, p->zText, p->nChar);
944       p->zText = zNew;
945       p->nAlloc = sqlite3DbMallocSize(p->db, zNew);
946       p->printfFlags |= SQLITE_PRINTF_MALLOCED;
947     }else{
948       sqlite3_str_reset(p);
949       setStrAccumError(p, SQLITE_NOMEM);
950       return 0;
951     }
952   }
953   return N;
954 }
955 
956 /*
957 ** Append N copies of character c to the given string buffer.
958 */
959 void sqlite3_str_appendchar(sqlite3_str *p, int N, char c){
960   testcase( p->nChar + (i64)N > 0x7fffffff );
961   if( p->nChar+(i64)N >= p->nAlloc && (N = sqlite3StrAccumEnlarge(p, N))<=0 ){
962     return;
963   }
964   while( (N--)>0 ) p->zText[p->nChar++] = c;
965 }
966 
967 /*
968 ** The StrAccum "p" is not large enough to accept N new bytes of z[].
969 ** So enlarge if first, then do the append.
970 **
971 ** This is a helper routine to sqlite3_str_append() that does special-case
972 ** work (enlarging the buffer) using tail recursion, so that the
973 ** sqlite3_str_append() routine can use fast calling semantics.
974 */
975 static void SQLITE_NOINLINE enlargeAndAppend(StrAccum *p, const char *z, int N){
976   N = sqlite3StrAccumEnlarge(p, N);
977   if( N>0 ){
978     memcpy(&p->zText[p->nChar], z, N);
979     p->nChar += N;
980   }
981 }
982 
983 /*
984 ** Append N bytes of text from z to the StrAccum object.  Increase the
985 ** size of the memory allocation for StrAccum if necessary.
986 */
987 void sqlite3_str_append(sqlite3_str *p, const char *z, int N){
988   assert( z!=0 || N==0 );
989   assert( p->zText!=0 || p->nChar==0 || p->accError );
990   assert( N>=0 );
991   assert( p->accError==0 || p->nAlloc==0 || p->mxAlloc==0 );
992   if( p->nChar+N >= p->nAlloc ){
993     enlargeAndAppend(p,z,N);
994   }else if( N ){
995     assert( p->zText );
996     p->nChar += N;
997     memcpy(&p->zText[p->nChar-N], z, N);
998   }
999 }
1000 
1001 /*
1002 ** Append the complete text of zero-terminated string z[] to the p string.
1003 */
1004 void sqlite3_str_appendall(sqlite3_str *p, const char *z){
1005   sqlite3_str_append(p, z, sqlite3Strlen30(z));
1006 }
1007 
1008 
1009 /*
1010 ** Finish off a string by making sure it is zero-terminated.
1011 ** Return a pointer to the resulting string.  Return a NULL
1012 ** pointer if any kind of error was encountered.
1013 */
1014 static SQLITE_NOINLINE char *strAccumFinishRealloc(StrAccum *p){
1015   char *zText;
1016   assert( p->mxAlloc>0 && !isMalloced(p) );
1017   zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
1018   if( zText ){
1019     memcpy(zText, p->zText, p->nChar+1);
1020     p->printfFlags |= SQLITE_PRINTF_MALLOCED;
1021   }else{
1022     setStrAccumError(p, SQLITE_NOMEM);
1023   }
1024   p->zText = zText;
1025   return zText;
1026 }
1027 char *sqlite3StrAccumFinish(StrAccum *p){
1028   if( p->zText ){
1029     p->zText[p->nChar] = 0;
1030     if( p->mxAlloc>0 && !isMalloced(p) ){
1031       return strAccumFinishRealloc(p);
1032     }
1033   }
1034   return p->zText;
1035 }
1036 
1037 /*
1038 ** This singleton is an sqlite3_str object that is returned if
1039 ** sqlite3_malloc() fails to provide space for a real one.  This
1040 ** sqlite3_str object accepts no new text and always returns
1041 ** an SQLITE_NOMEM error.
1042 */
1043 static sqlite3_str sqlite3OomStr = {
1044    0, 0, 0, 0, 0, SQLITE_NOMEM, 0
1045 };
1046 
1047 /* Finalize a string created using sqlite3_str_new().
1048 */
1049 char *sqlite3_str_finish(sqlite3_str *p){
1050   char *z;
1051   if( p!=0 && p!=&sqlite3OomStr ){
1052     z = sqlite3StrAccumFinish(p);
1053     sqlite3_free(p);
1054   }else{
1055     z = 0;
1056   }
1057   return z;
1058 }
1059 
1060 /* Return any error code associated with p */
1061 int sqlite3_str_errcode(sqlite3_str *p){
1062   return p ? p->accError : SQLITE_NOMEM;
1063 }
1064 
1065 /* Return the current length of p in bytes */
1066 int sqlite3_str_length(sqlite3_str *p){
1067   return p ? p->nChar : 0;
1068 }
1069 
1070 /* Return the current value for p */
1071 char *sqlite3_str_value(sqlite3_str *p){
1072   if( p==0 || p->nChar==0 ) return 0;
1073   p->zText[p->nChar] = 0;
1074   return p->zText;
1075 }
1076 
1077 /*
1078 ** Reset an StrAccum string.  Reclaim all malloced memory.
1079 */
1080 void sqlite3_str_reset(StrAccum *p){
1081   if( isMalloced(p) ){
1082     sqlite3DbFree(p->db, p->zText);
1083     p->printfFlags &= ~SQLITE_PRINTF_MALLOCED;
1084   }
1085   p->nAlloc = 0;
1086   p->nChar = 0;
1087   p->zText = 0;
1088 }
1089 
1090 /*
1091 ** Initialize a string accumulator.
1092 **
1093 ** p:     The accumulator to be initialized.
1094 ** db:    Pointer to a database connection.  May be NULL.  Lookaside
1095 **        memory is used if not NULL. db->mallocFailed is set appropriately
1096 **        when not NULL.
1097 ** zBase: An initial buffer.  May be NULL in which case the initial buffer
1098 **        is malloced.
1099 ** n:     Size of zBase in bytes.  If total space requirements never exceed
1100 **        n then no memory allocations ever occur.
1101 ** mx:    Maximum number of bytes to accumulate.  If mx==0 then no memory
1102 **        allocations will ever occur.
1103 */
1104 void sqlite3StrAccumInit(StrAccum *p, sqlite3 *db, char *zBase, int n, int mx){
1105   p->zText = zBase;
1106   p->db = db;
1107   p->nAlloc = n;
1108   p->mxAlloc = mx;
1109   p->nChar = 0;
1110   p->accError = 0;
1111   p->printfFlags = 0;
1112 }
1113 
1114 /* Allocate and initialize a new dynamic string object */
1115 sqlite3_str *sqlite3_str_new(sqlite3 *db){
1116   sqlite3_str *p = sqlite3_malloc64(sizeof(*p));
1117   if( p ){
1118     sqlite3StrAccumInit(p, 0, 0, 0,
1119             db ? db->aLimit[SQLITE_LIMIT_LENGTH] : SQLITE_MAX_LENGTH);
1120   }else{
1121     p = &sqlite3OomStr;
1122   }
1123   return p;
1124 }
1125 
1126 /*
1127 ** Print into memory obtained from sqliteMalloc().  Use the internal
1128 ** %-conversion extensions.
1129 */
1130 char *sqlite3VMPrintf(sqlite3 *db, const char *zFormat, va_list ap){
1131   char *z;
1132   char zBase[SQLITE_PRINT_BUF_SIZE];
1133   StrAccum acc;
1134   assert( db!=0 );
1135   sqlite3StrAccumInit(&acc, db, zBase, sizeof(zBase),
1136                       db->aLimit[SQLITE_LIMIT_LENGTH]);
1137   acc.printfFlags = SQLITE_PRINTF_INTERNAL;
1138   sqlite3_str_vappendf(&acc, zFormat, ap);
1139   z = sqlite3StrAccumFinish(&acc);
1140   if( acc.accError==SQLITE_NOMEM ){
1141     sqlite3OomFault(db);
1142   }
1143   return z;
1144 }
1145 
1146 /*
1147 ** Print into memory obtained from sqliteMalloc().  Use the internal
1148 ** %-conversion extensions.
1149 */
1150 char *sqlite3MPrintf(sqlite3 *db, const char *zFormat, ...){
1151   va_list ap;
1152   char *z;
1153   va_start(ap, zFormat);
1154   z = sqlite3VMPrintf(db, zFormat, ap);
1155   va_end(ap);
1156   return z;
1157 }
1158 
1159 /*
1160 ** Print into memory obtained from sqlite3_malloc().  Omit the internal
1161 ** %-conversion extensions.
1162 */
1163 char *sqlite3_vmprintf(const char *zFormat, va_list ap){
1164   char *z;
1165   char zBase[SQLITE_PRINT_BUF_SIZE];
1166   StrAccum acc;
1167 
1168 #ifdef SQLITE_ENABLE_API_ARMOR
1169   if( zFormat==0 ){
1170     (void)SQLITE_MISUSE_BKPT;
1171     return 0;
1172   }
1173 #endif
1174 #ifndef SQLITE_OMIT_AUTOINIT
1175   if( sqlite3_initialize() ) return 0;
1176 #endif
1177   sqlite3StrAccumInit(&acc, 0, zBase, sizeof(zBase), SQLITE_MAX_LENGTH);
1178   sqlite3_str_vappendf(&acc, zFormat, ap);
1179   z = sqlite3StrAccumFinish(&acc);
1180   return z;
1181 }
1182 
1183 /*
1184 ** Print into memory obtained from sqlite3_malloc()().  Omit the internal
1185 ** %-conversion extensions.
1186 */
1187 char *sqlite3_mprintf(const char *zFormat, ...){
1188   va_list ap;
1189   char *z;
1190 #ifndef SQLITE_OMIT_AUTOINIT
1191   if( sqlite3_initialize() ) return 0;
1192 #endif
1193   va_start(ap, zFormat);
1194   z = sqlite3_vmprintf(zFormat, ap);
1195   va_end(ap);
1196   return z;
1197 }
1198 
1199 /*
1200 ** sqlite3_snprintf() works like snprintf() except that it ignores the
1201 ** current locale settings.  This is important for SQLite because we
1202 ** are not able to use a "," as the decimal point in place of "." as
1203 ** specified by some locales.
1204 **
1205 ** Oops:  The first two arguments of sqlite3_snprintf() are backwards
1206 ** from the snprintf() standard.  Unfortunately, it is too late to change
1207 ** this without breaking compatibility, so we just have to live with the
1208 ** mistake.
1209 **
1210 ** sqlite3_vsnprintf() is the varargs version.
1211 */
1212 char *sqlite3_vsnprintf(int n, char *zBuf, const char *zFormat, va_list ap){
1213   StrAccum acc;
1214   if( n<=0 ) return zBuf;
1215 #ifdef SQLITE_ENABLE_API_ARMOR
1216   if( zBuf==0 || zFormat==0 ) {
1217     (void)SQLITE_MISUSE_BKPT;
1218     if( zBuf ) zBuf[0] = 0;
1219     return zBuf;
1220   }
1221 #endif
1222   sqlite3StrAccumInit(&acc, 0, zBuf, n, 0);
1223   sqlite3_str_vappendf(&acc, zFormat, ap);
1224   zBuf[acc.nChar] = 0;
1225   return zBuf;
1226 }
1227 char *sqlite3_snprintf(int n, char *zBuf, const char *zFormat, ...){
1228   char *z;
1229   va_list ap;
1230   va_start(ap,zFormat);
1231   z = sqlite3_vsnprintf(n, zBuf, zFormat, ap);
1232   va_end(ap);
1233   return z;
1234 }
1235 
1236 /*
1237 ** This is the routine that actually formats the sqlite3_log() message.
1238 ** We house it in a separate routine from sqlite3_log() to avoid using
1239 ** stack space on small-stack systems when logging is disabled.
1240 **
1241 ** sqlite3_log() must render into a static buffer.  It cannot dynamically
1242 ** allocate memory because it might be called while the memory allocator
1243 ** mutex is held.
1244 **
1245 ** sqlite3_str_vappendf() might ask for *temporary* memory allocations for
1246 ** certain format characters (%q) or for very large precisions or widths.
1247 ** Care must be taken that any sqlite3_log() calls that occur while the
1248 ** memory mutex is held do not use these mechanisms.
1249 */
1250 static void renderLogMsg(int iErrCode, const char *zFormat, va_list ap){
1251   StrAccum acc;                          /* String accumulator */
1252   char zMsg[SQLITE_PRINT_BUF_SIZE*3];    /* Complete log message */
1253 
1254   sqlite3StrAccumInit(&acc, 0, zMsg, sizeof(zMsg), 0);
1255   sqlite3_str_vappendf(&acc, zFormat, ap);
1256   sqlite3GlobalConfig.xLog(sqlite3GlobalConfig.pLogArg, iErrCode,
1257                            sqlite3StrAccumFinish(&acc));
1258 }
1259 
1260 /*
1261 ** Format and write a message to the log if logging is enabled.
1262 */
1263 void sqlite3_log(int iErrCode, const char *zFormat, ...){
1264   va_list ap;                             /* Vararg list */
1265   if( sqlite3GlobalConfig.xLog ){
1266     va_start(ap, zFormat);
1267     renderLogMsg(iErrCode, zFormat, ap);
1268     va_end(ap);
1269   }
1270 }
1271 
1272 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
1273 /*
1274 ** A version of printf() that understands %lld.  Used for debugging.
1275 ** The printf() built into some versions of windows does not understand %lld
1276 ** and segfaults if you give it a long long int.
1277 */
1278 void sqlite3DebugPrintf(const char *zFormat, ...){
1279   va_list ap;
1280   StrAccum acc;
1281   char zBuf[SQLITE_PRINT_BUF_SIZE*10];
1282   sqlite3StrAccumInit(&acc, 0, zBuf, sizeof(zBuf), 0);
1283   va_start(ap,zFormat);
1284   sqlite3_str_vappendf(&acc, zFormat, ap);
1285   va_end(ap);
1286   sqlite3StrAccumFinish(&acc);
1287 #ifdef SQLITE_OS_TRACE_PROC
1288   {
1289     extern void SQLITE_OS_TRACE_PROC(const char *zBuf, int nBuf);
1290     SQLITE_OS_TRACE_PROC(zBuf, sizeof(zBuf));
1291   }
1292 #else
1293   fprintf(stdout,"%s", zBuf);
1294   fflush(stdout);
1295 #endif
1296 }
1297 #endif
1298 
1299 
1300 /*
1301 ** variable-argument wrapper around sqlite3_str_vappendf(). The bFlags argument
1302 ** can contain the bit SQLITE_PRINTF_INTERNAL enable internal formats.
1303 */
1304 void sqlite3_str_appendf(StrAccum *p, const char *zFormat, ...){
1305   va_list ap;
1306   va_start(ap,zFormat);
1307   sqlite3_str_vappendf(p, zFormat, ap);
1308   va_end(ap);
1309 }
1310