xref: /sqlite-3.40.0/src/printf.c (revision a3fdec71)
1 /*
2 ** The "printf" code that follows dates from the 1980's.  It is in
3 ** the public domain.  The original comments are included here for
4 ** completeness.  They are very out-of-date but might be useful as
5 ** an historical reference.  Most of the "enhancements" have been backed
6 ** out so that the functionality is now the same as standard printf().
7 **
8 **************************************************************************
9 **
10 ** This file contains code for a set of "printf"-like routines.  These
11 ** routines format strings much like the printf() from the standard C
12 ** library, though the implementation here has enhancements to support
13 ** SQLlite.
14 */
15 #include "sqliteInt.h"
16 
17 /*
18 ** Conversion types fall into various categories as defined by the
19 ** following enumeration.
20 */
21 #define etRADIX       1 /* Integer types.  %d, %x, %o, and so forth */
22 #define etFLOAT       2 /* Floating point.  %f */
23 #define etEXP         3 /* Exponentional notation. %e and %E */
24 #define etGENERIC     4 /* Floating or exponential, depending on exponent. %g */
25 #define etSIZE        5 /* Return number of characters processed so far. %n */
26 #define etSTRING      6 /* Strings. %s */
27 #define etDYNSTRING   7 /* Dynamically allocated strings. %z */
28 #define etPERCENT     8 /* Percent symbol. %% */
29 #define etCHARX       9 /* Characters. %c */
30 /* The rest are extensions, not normally found in printf() */
31 #define etSQLESCAPE  10 /* Strings with '\'' doubled.  %q */
32 #define etSQLESCAPE2 11 /* Strings with '\'' doubled and enclosed in '',
33                           NULL pointers replaced by SQL NULL.  %Q */
34 #define etTOKEN      12 /* a pointer to a Token structure */
35 #define etSRCLIST    13 /* a pointer to a SrcList */
36 #define etPOINTER    14 /* The %p conversion */
37 #define etSQLESCAPE3 15 /* %w -> Strings with '\"' doubled */
38 #define etORDINAL    16 /* %r -> 1st, 2nd, 3rd, 4th, etc.  English only */
39 
40 #define etINVALID     0 /* Any unrecognized conversion type */
41 
42 
43 /*
44 ** An "etByte" is an 8-bit unsigned value.
45 */
46 typedef unsigned char etByte;
47 
48 /*
49 ** Each builtin conversion character (ex: the 'd' in "%d") is described
50 ** by an instance of the following structure
51 */
52 typedef struct et_info {   /* Information about each format field */
53   char fmttype;            /* The format field code letter */
54   etByte base;             /* The base for radix conversion */
55   etByte flags;            /* One or more of FLAG_ constants below */
56   etByte type;             /* Conversion paradigm */
57   etByte charset;          /* Offset into aDigits[] of the digits string */
58   etByte prefix;           /* Offset into aPrefix[] of the prefix string */
59 } et_info;
60 
61 /*
62 ** Allowed values for et_info.flags
63 */
64 #define FLAG_SIGNED  1     /* True if the value to convert is signed */
65 #define FLAG_INTERN  2     /* True if for internal use only */
66 #define FLAG_STRING  4     /* Allow infinity precision */
67 
68 
69 /*
70 ** The following table is searched linearly, so it is good to put the
71 ** most frequently used conversion types first.
72 */
73 static const char aDigits[] = "0123456789ABCDEF0123456789abcdef";
74 static const char aPrefix[] = "-x0\000X0";
75 static const et_info fmtinfo[] = {
76   {  'd', 10, 1, etRADIX,      0,  0 },
77   {  's',  0, 4, etSTRING,     0,  0 },
78   {  'g',  0, 1, etGENERIC,    30, 0 },
79   {  'z',  0, 4, etDYNSTRING,  0,  0 },
80   {  'q',  0, 4, etSQLESCAPE,  0,  0 },
81   {  'Q',  0, 4, etSQLESCAPE2, 0,  0 },
82   {  'w',  0, 4, etSQLESCAPE3, 0,  0 },
83   {  'c',  0, 0, etCHARX,      0,  0 },
84   {  'o',  8, 0, etRADIX,      0,  2 },
85   {  'u', 10, 0, etRADIX,      0,  0 },
86   {  'x', 16, 0, etRADIX,      16, 1 },
87   {  'X', 16, 0, etRADIX,      0,  4 },
88 #ifndef SQLITE_OMIT_FLOATING_POINT
89   {  'f',  0, 1, etFLOAT,      0,  0 },
90   {  'e',  0, 1, etEXP,        30, 0 },
91   {  'E',  0, 1, etEXP,        14, 0 },
92   {  'G',  0, 1, etGENERIC,    14, 0 },
93 #endif
94   {  'i', 10, 1, etRADIX,      0,  0 },
95   {  'n',  0, 0, etSIZE,       0,  0 },
96   {  '%',  0, 0, etPERCENT,    0,  0 },
97   {  'p', 16, 0, etPOINTER,    0,  1 },
98 
99 /* All the rest have the FLAG_INTERN bit set and are thus for internal
100 ** use only */
101   {  'T',  0, 2, etTOKEN,      0,  0 },
102   {  'S',  0, 2, etSRCLIST,    0,  0 },
103   {  'r', 10, 3, etORDINAL,    0,  0 },
104 };
105 
106 /*
107 ** If SQLITE_OMIT_FLOATING_POINT is defined, then none of the floating point
108 ** conversions will work.
109 */
110 #ifndef SQLITE_OMIT_FLOATING_POINT
111 /*
112 ** "*val" is a double such that 0.1 <= *val < 10.0
113 ** Return the ascii code for the leading digit of *val, then
114 ** multiply "*val" by 10.0 to renormalize.
115 **
116 ** Example:
117 **     input:     *val = 3.14159
118 **     output:    *val = 1.4159    function return = '3'
119 **
120 ** The counter *cnt is incremented each time.  After counter exceeds
121 ** 16 (the number of significant digits in a 64-bit float) '0' is
122 ** always returned.
123 */
124 static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
125   int digit;
126   LONGDOUBLE_TYPE d;
127   if( (*cnt)<=0 ) return '0';
128   (*cnt)--;
129   digit = (int)*val;
130   d = digit;
131   digit += '0';
132   *val = (*val - d)*10.0;
133   return (char)digit;
134 }
135 #endif /* SQLITE_OMIT_FLOATING_POINT */
136 
137 /*
138 ** Append N space characters to the given string buffer.
139 */
140 void sqlite3AppendSpace(StrAccum *pAccum, int N){
141   static const char zSpaces[] = "                             ";
142   while( N>=(int)sizeof(zSpaces)-1 ){
143     sqlite3StrAccumAppend(pAccum, zSpaces, sizeof(zSpaces)-1);
144     N -= sizeof(zSpaces)-1;
145   }
146   if( N>0 ){
147     sqlite3StrAccumAppend(pAccum, zSpaces, N);
148   }
149 }
150 
151 /*
152 ** Set the StrAccum object to an error mode.
153 */
154 static void setStrAccumError(StrAccum *p, u8 eError){
155   p->accError = eError;
156   p->nAlloc = 0;
157 }
158 
159 /*
160 ** Extra argument values from a PrintfArguments object
161 */
162 static sqlite3_int64 getIntArg(PrintfArguments *p){
163   if( p->nArg<=p->nUsed ) return 0;
164   return sqlite3_value_int64(p->apArg[p->nUsed++]);
165 }
166 static double getDoubleArg(PrintfArguments *p){
167   if( p->nArg<=p->nUsed ) return 0.0;
168   return sqlite3_value_double(p->apArg[p->nUsed++]);
169 }
170 static char *getTextArg(PrintfArguments *p){
171   if( p->nArg<=p->nUsed ) return 0;
172   return (char*)sqlite3_value_text(p->apArg[p->nUsed++]);
173 }
174 
175 
176 /*
177 ** On machines with a small stack size, you can redefine the
178 ** SQLITE_PRINT_BUF_SIZE to be something smaller, if desired.
179 */
180 #ifndef SQLITE_PRINT_BUF_SIZE
181 # define SQLITE_PRINT_BUF_SIZE 70
182 #endif
183 #define etBUFSIZE SQLITE_PRINT_BUF_SIZE  /* Size of the output buffer */
184 
185 /*
186 ** Render a string given by "fmt" into the StrAccum object.
187 */
188 void sqlite3VXPrintf(
189   StrAccum *pAccum,          /* Accumulate results here */
190   u32 bFlags,                /* SQLITE_PRINTF_* flags */
191   const char *fmt,           /* Format string */
192   va_list ap                 /* arguments */
193 ){
194   int c;                     /* Next character in the format string */
195   char *bufpt;               /* Pointer to the conversion buffer */
196   int precision;             /* Precision of the current field */
197   int length;                /* Length of the field */
198   int idx;                   /* A general purpose loop counter */
199   int width;                 /* Width of the current field */
200   etByte flag_leftjustify;   /* True if "-" flag is present */
201   etByte flag_plussign;      /* True if "+" flag is present */
202   etByte flag_blanksign;     /* True if " " flag is present */
203   etByte flag_alternateform; /* True if "#" flag is present */
204   etByte flag_altform2;      /* True if "!" flag is present */
205   etByte flag_zeropad;       /* True if field width constant starts with zero */
206   etByte flag_long;          /* True if "l" flag is present */
207   etByte flag_longlong;      /* True if the "ll" flag is present */
208   etByte done;               /* Loop termination flag */
209   etByte xtype = 0;          /* Conversion paradigm */
210   u8 bArgList;               /* True for SQLITE_PRINTF_SQLFUNC */
211   u8 useIntern;              /* Ok to use internal conversions (ex: %T) */
212   char prefix;               /* Prefix character.  "+" or "-" or " " or '\0'. */
213   sqlite_uint64 longvalue;   /* Value for integer types */
214   LONGDOUBLE_TYPE realvalue; /* Value for real types */
215   const et_info *infop;      /* Pointer to the appropriate info structure */
216   char *zOut;                /* Rendering buffer */
217   int nOut;                  /* Size of the rendering buffer */
218   char *zExtra;              /* Malloced memory used by some conversion */
219 #ifndef SQLITE_OMIT_FLOATING_POINT
220   int  exp, e2;              /* exponent of real numbers */
221   int nsd;                   /* Number of significant digits returned */
222   double rounder;            /* Used for rounding floating point values */
223   etByte flag_dp;            /* True if decimal point should be shown */
224   etByte flag_rtz;           /* True if trailing zeros should be removed */
225 #endif
226   PrintfArguments *pArgList = 0; /* Arguments for SQLITE_PRINTF_SQLFUNC */
227   char buf[etBUFSIZE];       /* Conversion buffer */
228 
229   bufpt = 0;
230   if( bFlags ){
231     if( (bArgList = (bFlags & SQLITE_PRINTF_SQLFUNC))!=0 ){
232       pArgList = va_arg(ap, PrintfArguments*);
233     }
234     useIntern = bFlags & SQLITE_PRINTF_INTERNAL;
235   }else{
236     bArgList = useIntern = 0;
237   }
238   for(; (c=(*fmt))!=0; ++fmt){
239     if( c!='%' ){
240       int amt;
241       bufpt = (char *)fmt;
242       amt = 1;
243       while( (c=(*++fmt))!='%' && c!=0 ) amt++;
244       sqlite3StrAccumAppend(pAccum, bufpt, amt);
245       if( c==0 ) break;
246     }
247     if( (c=(*++fmt))==0 ){
248       sqlite3StrAccumAppend(pAccum, "%", 1);
249       break;
250     }
251     /* Find out what flags are present */
252     flag_leftjustify = flag_plussign = flag_blanksign =
253      flag_alternateform = flag_altform2 = flag_zeropad = 0;
254     done = 0;
255     do{
256       switch( c ){
257         case '-':   flag_leftjustify = 1;     break;
258         case '+':   flag_plussign = 1;        break;
259         case ' ':   flag_blanksign = 1;       break;
260         case '#':   flag_alternateform = 1;   break;
261         case '!':   flag_altform2 = 1;        break;
262         case '0':   flag_zeropad = 1;         break;
263         default:    done = 1;                 break;
264       }
265     }while( !done && (c=(*++fmt))!=0 );
266     /* Get the field width */
267     width = 0;
268     if( c=='*' ){
269       if( bArgList ){
270         width = (int)getIntArg(pArgList);
271       }else{
272         width = va_arg(ap,int);
273       }
274       if( width<0 ){
275         flag_leftjustify = 1;
276         width = -width;
277       }
278       c = *++fmt;
279     }else{
280       while( c>='0' && c<='9' ){
281         width = width*10 + c - '0';
282         c = *++fmt;
283       }
284     }
285     /* Get the precision */
286     if( c=='.' ){
287       precision = 0;
288       c = *++fmt;
289       if( c=='*' ){
290         if( bArgList ){
291           precision = (int)getIntArg(pArgList);
292         }else{
293           precision = va_arg(ap,int);
294         }
295         if( precision<0 ) precision = -precision;
296         c = *++fmt;
297       }else{
298         while( c>='0' && c<='9' ){
299           precision = precision*10 + c - '0';
300           c = *++fmt;
301         }
302       }
303     }else{
304       precision = -1;
305     }
306     /* Get the conversion type modifier */
307     if( c=='l' ){
308       flag_long = 1;
309       c = *++fmt;
310       if( c=='l' ){
311         flag_longlong = 1;
312         c = *++fmt;
313       }else{
314         flag_longlong = 0;
315       }
316     }else{
317       flag_long = flag_longlong = 0;
318     }
319     /* Fetch the info entry for the field */
320     infop = &fmtinfo[0];
321     xtype = etINVALID;
322     for(idx=0; idx<ArraySize(fmtinfo); idx++){
323       if( c==fmtinfo[idx].fmttype ){
324         infop = &fmtinfo[idx];
325         if( useIntern || (infop->flags & FLAG_INTERN)==0 ){
326           xtype = infop->type;
327         }else{
328           return;
329         }
330         break;
331       }
332     }
333     zExtra = 0;
334 
335     /*
336     ** At this point, variables are initialized as follows:
337     **
338     **   flag_alternateform          TRUE if a '#' is present.
339     **   flag_altform2               TRUE if a '!' is present.
340     **   flag_plussign               TRUE if a '+' is present.
341     **   flag_leftjustify            TRUE if a '-' is present or if the
342     **                               field width was negative.
343     **   flag_zeropad                TRUE if the width began with 0.
344     **   flag_long                   TRUE if the letter 'l' (ell) prefixed
345     **                               the conversion character.
346     **   flag_longlong               TRUE if the letter 'll' (ell ell) prefixed
347     **                               the conversion character.
348     **   flag_blanksign              TRUE if a ' ' is present.
349     **   width                       The specified field width.  This is
350     **                               always non-negative.  Zero is the default.
351     **   precision                   The specified precision.  The default
352     **                               is -1.
353     **   xtype                       The class of the conversion.
354     **   infop                       Pointer to the appropriate info struct.
355     */
356     switch( xtype ){
357       case etPOINTER:
358         flag_longlong = sizeof(char*)==sizeof(i64);
359         flag_long = sizeof(char*)==sizeof(long int);
360         /* Fall through into the next case */
361       case etORDINAL:
362       case etRADIX:
363         if( infop->flags & FLAG_SIGNED ){
364           i64 v;
365           if( bArgList ){
366             v = getIntArg(pArgList);
367           }else if( flag_longlong ){
368             v = va_arg(ap,i64);
369           }else if( flag_long ){
370             v = va_arg(ap,long int);
371           }else{
372             v = va_arg(ap,int);
373           }
374           if( v<0 ){
375             if( v==SMALLEST_INT64 ){
376               longvalue = ((u64)1)<<63;
377             }else{
378               longvalue = -v;
379             }
380             prefix = '-';
381           }else{
382             longvalue = v;
383             if( flag_plussign )        prefix = '+';
384             else if( flag_blanksign )  prefix = ' ';
385             else                       prefix = 0;
386           }
387         }else{
388           if( bArgList ){
389             longvalue = (u64)getIntArg(pArgList);
390           }else if( flag_longlong ){
391             longvalue = va_arg(ap,u64);
392           }else if( flag_long ){
393             longvalue = va_arg(ap,unsigned long int);
394           }else{
395             longvalue = va_arg(ap,unsigned int);
396           }
397           prefix = 0;
398         }
399         if( longvalue==0 ) flag_alternateform = 0;
400         if( flag_zeropad && precision<width-(prefix!=0) ){
401           precision = width-(prefix!=0);
402         }
403         if( precision<etBUFSIZE-10 ){
404           nOut = etBUFSIZE;
405           zOut = buf;
406         }else{
407           nOut = precision + 10;
408           zOut = zExtra = sqlite3Malloc( nOut );
409           if( zOut==0 ){
410             setStrAccumError(pAccum, STRACCUM_NOMEM);
411             return;
412           }
413         }
414         bufpt = &zOut[nOut-1];
415         if( xtype==etORDINAL ){
416           static const char zOrd[] = "thstndrd";
417           int x = (int)(longvalue % 10);
418           if( x>=4 || (longvalue/10)%10==1 ){
419             x = 0;
420           }
421           *(--bufpt) = zOrd[x*2+1];
422           *(--bufpt) = zOrd[x*2];
423         }
424         {
425           register const char *cset;      /* Use registers for speed */
426           register int base;
427           cset = &aDigits[infop->charset];
428           base = infop->base;
429           do{                                           /* Convert to ascii */
430             *(--bufpt) = cset[longvalue%base];
431             longvalue = longvalue/base;
432           }while( longvalue>0 );
433         }
434         length = (int)(&zOut[nOut-1]-bufpt);
435         for(idx=precision-length; idx>0; idx--){
436           *(--bufpt) = '0';                             /* Zero pad */
437         }
438         if( prefix ) *(--bufpt) = prefix;               /* Add sign */
439         if( flag_alternateform && infop->prefix ){      /* Add "0" or "0x" */
440           const char *pre;
441           char x;
442           pre = &aPrefix[infop->prefix];
443           for(; (x=(*pre))!=0; pre++) *(--bufpt) = x;
444         }
445         length = (int)(&zOut[nOut-1]-bufpt);
446         break;
447       case etFLOAT:
448       case etEXP:
449       case etGENERIC:
450         if( bArgList ){
451           realvalue = getDoubleArg(pArgList);
452         }else{
453           realvalue = va_arg(ap,double);
454         }
455 #ifdef SQLITE_OMIT_FLOATING_POINT
456         length = 0;
457 #else
458         if( precision<0 ) precision = 6;         /* Set default precision */
459         if( realvalue<0.0 ){
460           realvalue = -realvalue;
461           prefix = '-';
462         }else{
463           if( flag_plussign )          prefix = '+';
464           else if( flag_blanksign )    prefix = ' ';
465           else                         prefix = 0;
466         }
467         if( xtype==etGENERIC && precision>0 ) precision--;
468         for(idx=precision, rounder=0.5; idx>0; idx--, rounder*=0.1){}
469         if( xtype==etFLOAT ) realvalue += rounder;
470         /* Normalize realvalue to within 10.0 > realvalue >= 1.0 */
471         exp = 0;
472         if( sqlite3IsNaN((double)realvalue) ){
473           bufpt = "NaN";
474           length = 3;
475           break;
476         }
477         if( realvalue>0.0 ){
478           LONGDOUBLE_TYPE scale = 1.0;
479           while( realvalue>=1e100*scale && exp<=350 ){ scale *= 1e100;exp+=100;}
480           while( realvalue>=1e64*scale && exp<=350 ){ scale *= 1e64; exp+=64; }
481           while( realvalue>=1e8*scale && exp<=350 ){ scale *= 1e8; exp+=8; }
482           while( realvalue>=10.0*scale && exp<=350 ){ scale *= 10.0; exp++; }
483           realvalue /= scale;
484           while( realvalue<1e-8 ){ realvalue *= 1e8; exp-=8; }
485           while( realvalue<1.0 ){ realvalue *= 10.0; exp--; }
486           if( exp>350 ){
487             if( prefix=='-' ){
488               bufpt = "-Inf";
489             }else if( prefix=='+' ){
490               bufpt = "+Inf";
491             }else{
492               bufpt = "Inf";
493             }
494             length = sqlite3Strlen30(bufpt);
495             break;
496           }
497         }
498         bufpt = buf;
499         /*
500         ** If the field type is etGENERIC, then convert to either etEXP
501         ** or etFLOAT, as appropriate.
502         */
503         if( xtype!=etFLOAT ){
504           realvalue += rounder;
505           if( realvalue>=10.0 ){ realvalue *= 0.1; exp++; }
506         }
507         if( xtype==etGENERIC ){
508           flag_rtz = !flag_alternateform;
509           if( exp<-4 || exp>precision ){
510             xtype = etEXP;
511           }else{
512             precision = precision - exp;
513             xtype = etFLOAT;
514           }
515         }else{
516           flag_rtz = flag_altform2;
517         }
518         if( xtype==etEXP ){
519           e2 = 0;
520         }else{
521           e2 = exp;
522         }
523         if( MAX(e2,0)+precision+width > etBUFSIZE - 15 ){
524           bufpt = zExtra = sqlite3Malloc( MAX(e2,0)+precision+width+15 );
525           if( bufpt==0 ){
526             setStrAccumError(pAccum, STRACCUM_NOMEM);
527             return;
528           }
529         }
530         zOut = bufpt;
531         nsd = 16 + flag_altform2*10;
532         flag_dp = (precision>0 ?1:0) | flag_alternateform | flag_altform2;
533         /* The sign in front of the number */
534         if( prefix ){
535           *(bufpt++) = prefix;
536         }
537         /* Digits prior to the decimal point */
538         if( e2<0 ){
539           *(bufpt++) = '0';
540         }else{
541           for(; e2>=0; e2--){
542             *(bufpt++) = et_getdigit(&realvalue,&nsd);
543           }
544         }
545         /* The decimal point */
546         if( flag_dp ){
547           *(bufpt++) = '.';
548         }
549         /* "0" digits after the decimal point but before the first
550         ** significant digit of the number */
551         for(e2++; e2<0; precision--, e2++){
552           assert( precision>0 );
553           *(bufpt++) = '0';
554         }
555         /* Significant digits after the decimal point */
556         while( (precision--)>0 ){
557           *(bufpt++) = et_getdigit(&realvalue,&nsd);
558         }
559         /* Remove trailing zeros and the "." if no digits follow the "." */
560         if( flag_rtz && flag_dp ){
561           while( bufpt[-1]=='0' ) *(--bufpt) = 0;
562           assert( bufpt>zOut );
563           if( bufpt[-1]=='.' ){
564             if( flag_altform2 ){
565               *(bufpt++) = '0';
566             }else{
567               *(--bufpt) = 0;
568             }
569           }
570         }
571         /* Add the "eNNN" suffix */
572         if( xtype==etEXP ){
573           *(bufpt++) = aDigits[infop->charset];
574           if( exp<0 ){
575             *(bufpt++) = '-'; exp = -exp;
576           }else{
577             *(bufpt++) = '+';
578           }
579           if( exp>=100 ){
580             *(bufpt++) = (char)((exp/100)+'0');        /* 100's digit */
581             exp %= 100;
582           }
583           *(bufpt++) = (char)(exp/10+'0');             /* 10's digit */
584           *(bufpt++) = (char)(exp%10+'0');             /* 1's digit */
585         }
586         *bufpt = 0;
587 
588         /* The converted number is in buf[] and zero terminated. Output it.
589         ** Note that the number is in the usual order, not reversed as with
590         ** integer conversions. */
591         length = (int)(bufpt-zOut);
592         bufpt = zOut;
593 
594         /* Special case:  Add leading zeros if the flag_zeropad flag is
595         ** set and we are not left justified */
596         if( flag_zeropad && !flag_leftjustify && length < width){
597           int i;
598           int nPad = width - length;
599           for(i=width; i>=nPad; i--){
600             bufpt[i] = bufpt[i-nPad];
601           }
602           i = prefix!=0;
603           while( nPad-- ) bufpt[i++] = '0';
604           length = width;
605         }
606 #endif /* !defined(SQLITE_OMIT_FLOATING_POINT) */
607         break;
608       case etSIZE:
609         if( !bArgList ){
610           *(va_arg(ap,int*)) = pAccum->nChar;
611         }
612         length = width = 0;
613         break;
614       case etPERCENT:
615         buf[0] = '%';
616         bufpt = buf;
617         length = 1;
618         break;
619       case etCHARX:
620         if( bArgList ){
621           bufpt = getTextArg(pArgList);
622           c = bufpt ? bufpt[0] : 0;
623         }else{
624           c = va_arg(ap,int);
625         }
626         buf[0] = (char)c;
627         if( precision>=0 ){
628           for(idx=1; idx<precision; idx++) buf[idx] = (char)c;
629           length = precision;
630         }else{
631           length =1;
632         }
633         bufpt = buf;
634         break;
635       case etSTRING:
636       case etDYNSTRING:
637         if( bArgList ){
638           bufpt = getTextArg(pArgList);
639         }else{
640           bufpt = va_arg(ap,char*);
641         }
642         if( bufpt==0 ){
643           bufpt = "";
644         }else if( xtype==etDYNSTRING && !bArgList ){
645           zExtra = bufpt;
646         }
647         if( precision>=0 ){
648           for(length=0; length<precision && bufpt[length]; length++){}
649         }else{
650           length = sqlite3Strlen30(bufpt);
651         }
652         break;
653       case etSQLESCAPE:
654       case etSQLESCAPE2:
655       case etSQLESCAPE3: {
656         int i, j, k, n, isnull;
657         int needQuote;
658         char ch;
659         char q = ((xtype==etSQLESCAPE3)?'"':'\'');   /* Quote character */
660         char *escarg;
661 
662         if( bArgList ){
663           escarg = getTextArg(pArgList);
664         }else{
665           escarg = va_arg(ap,char*);
666         }
667         isnull = escarg==0;
668         if( isnull ) escarg = (xtype==etSQLESCAPE2 ? "NULL" : "(NULL)");
669         k = precision;
670         for(i=n=0; k!=0 && (ch=escarg[i])!=0; i++, k--){
671           if( ch==q )  n++;
672         }
673         needQuote = !isnull && xtype==etSQLESCAPE2;
674         n += i + 1 + needQuote*2;
675         if( n>etBUFSIZE ){
676           bufpt = zExtra = sqlite3Malloc( n );
677           if( bufpt==0 ){
678             setStrAccumError(pAccum, STRACCUM_NOMEM);
679             return;
680           }
681         }else{
682           bufpt = buf;
683         }
684         j = 0;
685         if( needQuote ) bufpt[j++] = q;
686         k = i;
687         for(i=0; i<k; i++){
688           bufpt[j++] = ch = escarg[i];
689           if( ch==q ) bufpt[j++] = ch;
690         }
691         if( needQuote ) bufpt[j++] = q;
692         bufpt[j] = 0;
693         length = j;
694         /* The precision in %q and %Q means how many input characters to
695         ** consume, not the length of the output...
696         ** if( precision>=0 && precision<length ) length = precision; */
697         break;
698       }
699       case etTOKEN: {
700         Token *pToken = va_arg(ap, Token*);
701         assert( bArgList==0 );
702         if( pToken && pToken->n ){
703           sqlite3StrAccumAppend(pAccum, (const char*)pToken->z, pToken->n);
704         }
705         length = width = 0;
706         break;
707       }
708       case etSRCLIST: {
709         SrcList *pSrc = va_arg(ap, SrcList*);
710         int k = va_arg(ap, int);
711         struct SrcList_item *pItem = &pSrc->a[k];
712         assert( bArgList==0 );
713         assert( k>=0 && k<pSrc->nSrc );
714         if( pItem->zDatabase ){
715           sqlite3StrAccumAppendAll(pAccum, pItem->zDatabase);
716           sqlite3StrAccumAppend(pAccum, ".", 1);
717         }
718         sqlite3StrAccumAppendAll(pAccum, pItem->zName);
719         length = width = 0;
720         break;
721       }
722       default: {
723         assert( xtype==etINVALID );
724         return;
725       }
726     }/* End switch over the format type */
727     /*
728     ** The text of the conversion is pointed to by "bufpt" and is
729     ** "length" characters long.  The field width is "width".  Do
730     ** the output.
731     */
732     if( !flag_leftjustify ){
733       register int nspace;
734       nspace = width-length;
735       if( nspace>0 ){
736         sqlite3AppendSpace(pAccum, nspace);
737       }
738     }
739     if( length>0 ){
740       sqlite3StrAccumAppend(pAccum, bufpt, length);
741     }
742     if( flag_leftjustify ){
743       register int nspace;
744       nspace = width-length;
745       if( nspace>0 ){
746         sqlite3AppendSpace(pAccum, nspace);
747       }
748     }
749     if( zExtra ) sqlite3_free(zExtra);
750   }/* End for loop over the format string */
751 } /* End of function */
752 
753 /*
754 ** Append N bytes of text from z to the StrAccum object.
755 */
756 void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
757   assert( z!=0 );
758   assert( p->zText!=0 || p->nChar==0 || p->accError );
759   assert( N>=0 );
760   assert( p->accError==0 || p->nAlloc==0 );
761   if( p->nChar+N >= p->nAlloc ){
762     char *zNew;
763     if( p->accError ){
764       testcase(p->accError==STRACCUM_TOOBIG);
765       testcase(p->accError==STRACCUM_NOMEM);
766       return;
767     }
768     if( !p->useMalloc ){
769       N = p->nAlloc - p->nChar - 1;
770       setStrAccumError(p, STRACCUM_TOOBIG);
771       if( N<=0 ){
772         return;
773       }
774     }else{
775       char *zOld = (p->zText==p->zBase ? 0 : p->zText);
776       i64 szNew = p->nChar;
777       szNew += N + 1;
778       if( szNew > p->mxAlloc ){
779         sqlite3StrAccumReset(p);
780         setStrAccumError(p, STRACCUM_TOOBIG);
781         return;
782       }else{
783         p->nAlloc = (int)szNew;
784       }
785       if( p->useMalloc==1 ){
786         zNew = sqlite3DbRealloc(p->db, zOld, p->nAlloc);
787       }else{
788         zNew = sqlite3_realloc(zOld, p->nAlloc);
789       }
790       if( zNew ){
791         if( zOld==0 && p->nChar>0 ) memcpy(zNew, p->zText, p->nChar);
792         p->zText = zNew;
793       }else{
794         sqlite3StrAccumReset(p);
795         setStrAccumError(p, STRACCUM_NOMEM);
796         return;
797       }
798     }
799   }
800   assert( p->zText );
801   memcpy(&p->zText[p->nChar], z, N);
802   p->nChar += N;
803 }
804 
805 /*
806 ** Append the complete text of zero-terminated string z[] to the p string.
807 */
808 void sqlite3StrAccumAppendAll(StrAccum *p, const char *z){
809   sqlite3StrAccumAppend(p, z, sqlite3Strlen30(z));
810 }
811 
812 
813 /*
814 ** Finish off a string by making sure it is zero-terminated.
815 ** Return a pointer to the resulting string.  Return a NULL
816 ** pointer if any kind of error was encountered.
817 */
818 char *sqlite3StrAccumFinish(StrAccum *p){
819   if( p->zText ){
820     p->zText[p->nChar] = 0;
821     if( p->useMalloc && p->zText==p->zBase ){
822       if( p->useMalloc==1 ){
823         p->zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
824       }else{
825         p->zText = sqlite3_malloc(p->nChar+1);
826       }
827       if( p->zText ){
828         memcpy(p->zText, p->zBase, p->nChar+1);
829       }else{
830         setStrAccumError(p, STRACCUM_NOMEM);
831       }
832     }
833   }
834   return p->zText;
835 }
836 
837 /*
838 ** Reset an StrAccum string.  Reclaim all malloced memory.
839 */
840 void sqlite3StrAccumReset(StrAccum *p){
841   if( p->zText!=p->zBase ){
842     if( p->useMalloc==1 ){
843       sqlite3DbFree(p->db, p->zText);
844     }else{
845       sqlite3_free(p->zText);
846     }
847   }
848   p->zText = 0;
849 }
850 
851 /*
852 ** Initialize a string accumulator
853 */
854 void sqlite3StrAccumInit(StrAccum *p, char *zBase, int n, int mx){
855   p->zText = p->zBase = zBase;
856   p->db = 0;
857   p->nChar = 0;
858   p->nAlloc = n;
859   p->mxAlloc = mx;
860   p->useMalloc = 1;
861   p->accError = 0;
862 }
863 
864 /*
865 ** Print into memory obtained from sqliteMalloc().  Use the internal
866 ** %-conversion extensions.
867 */
868 char *sqlite3VMPrintf(sqlite3 *db, const char *zFormat, va_list ap){
869   char *z;
870   char zBase[SQLITE_PRINT_BUF_SIZE];
871   StrAccum acc;
872   assert( db!=0 );
873   sqlite3StrAccumInit(&acc, zBase, sizeof(zBase),
874                       db->aLimit[SQLITE_LIMIT_LENGTH]);
875   acc.db = db;
876   sqlite3VXPrintf(&acc, SQLITE_PRINTF_INTERNAL, zFormat, ap);
877   z = sqlite3StrAccumFinish(&acc);
878   if( acc.accError==STRACCUM_NOMEM ){
879     db->mallocFailed = 1;
880   }
881   return z;
882 }
883 
884 /*
885 ** Print into memory obtained from sqliteMalloc().  Use the internal
886 ** %-conversion extensions.
887 */
888 char *sqlite3MPrintf(sqlite3 *db, const char *zFormat, ...){
889   va_list ap;
890   char *z;
891   va_start(ap, zFormat);
892   z = sqlite3VMPrintf(db, zFormat, ap);
893   va_end(ap);
894   return z;
895 }
896 
897 /*
898 ** Like sqlite3MPrintf(), but call sqlite3DbFree() on zStr after formatting
899 ** the string and before returnning.  This routine is intended to be used
900 ** to modify an existing string.  For example:
901 **
902 **       x = sqlite3MPrintf(db, x, "prefix %s suffix", x);
903 **
904 */
905 char *sqlite3MAppendf(sqlite3 *db, char *zStr, const char *zFormat, ...){
906   va_list ap;
907   char *z;
908   va_start(ap, zFormat);
909   z = sqlite3VMPrintf(db, zFormat, ap);
910   va_end(ap);
911   sqlite3DbFree(db, zStr);
912   return z;
913 }
914 
915 /*
916 ** Print into memory obtained from sqlite3_malloc().  Omit the internal
917 ** %-conversion extensions.
918 */
919 char *sqlite3_vmprintf(const char *zFormat, va_list ap){
920   char *z;
921   char zBase[SQLITE_PRINT_BUF_SIZE];
922   StrAccum acc;
923 #ifndef SQLITE_OMIT_AUTOINIT
924   if( sqlite3_initialize() ) return 0;
925 #endif
926   sqlite3StrAccumInit(&acc, zBase, sizeof(zBase), SQLITE_MAX_LENGTH);
927   acc.useMalloc = 2;
928   sqlite3VXPrintf(&acc, 0, zFormat, ap);
929   z = sqlite3StrAccumFinish(&acc);
930   return z;
931 }
932 
933 /*
934 ** Print into memory obtained from sqlite3_malloc()().  Omit the internal
935 ** %-conversion extensions.
936 */
937 char *sqlite3_mprintf(const char *zFormat, ...){
938   va_list ap;
939   char *z;
940 #ifndef SQLITE_OMIT_AUTOINIT
941   if( sqlite3_initialize() ) return 0;
942 #endif
943   va_start(ap, zFormat);
944   z = sqlite3_vmprintf(zFormat, ap);
945   va_end(ap);
946   return z;
947 }
948 
949 /*
950 ** sqlite3_snprintf() works like snprintf() except that it ignores the
951 ** current locale settings.  This is important for SQLite because we
952 ** are not able to use a "," as the decimal point in place of "." as
953 ** specified by some locales.
954 **
955 ** Oops:  The first two arguments of sqlite3_snprintf() are backwards
956 ** from the snprintf() standard.  Unfortunately, it is too late to change
957 ** this without breaking compatibility, so we just have to live with the
958 ** mistake.
959 **
960 ** sqlite3_vsnprintf() is the varargs version.
961 */
962 char *sqlite3_vsnprintf(int n, char *zBuf, const char *zFormat, va_list ap){
963   StrAccum acc;
964   if( n<=0 ) return zBuf;
965   sqlite3StrAccumInit(&acc, zBuf, n, 0);
966   acc.useMalloc = 0;
967   sqlite3VXPrintf(&acc, 0, zFormat, ap);
968   return sqlite3StrAccumFinish(&acc);
969 }
970 char *sqlite3_snprintf(int n, char *zBuf, const char *zFormat, ...){
971   char *z;
972   va_list ap;
973   va_start(ap,zFormat);
974   z = sqlite3_vsnprintf(n, zBuf, zFormat, ap);
975   va_end(ap);
976   return z;
977 }
978 
979 /*
980 ** This is the routine that actually formats the sqlite3_log() message.
981 ** We house it in a separate routine from sqlite3_log() to avoid using
982 ** stack space on small-stack systems when logging is disabled.
983 **
984 ** sqlite3_log() must render into a static buffer.  It cannot dynamically
985 ** allocate memory because it might be called while the memory allocator
986 ** mutex is held.
987 */
988 static void renderLogMsg(int iErrCode, const char *zFormat, va_list ap){
989   StrAccum acc;                          /* String accumulator */
990   char zMsg[SQLITE_PRINT_BUF_SIZE*3];    /* Complete log message */
991 
992   sqlite3StrAccumInit(&acc, zMsg, sizeof(zMsg), 0);
993   acc.useMalloc = 0;
994   sqlite3VXPrintf(&acc, 0, zFormat, ap);
995   sqlite3GlobalConfig.xLog(sqlite3GlobalConfig.pLogArg, iErrCode,
996                            sqlite3StrAccumFinish(&acc));
997 }
998 
999 /*
1000 ** Format and write a message to the log if logging is enabled.
1001 */
1002 void sqlite3_log(int iErrCode, const char *zFormat, ...){
1003   va_list ap;                             /* Vararg list */
1004   if( sqlite3GlobalConfig.xLog ){
1005     va_start(ap, zFormat);
1006     renderLogMsg(iErrCode, zFormat, ap);
1007     va_end(ap);
1008   }
1009 }
1010 
1011 #if defined(SQLITE_DEBUG)
1012 /*
1013 ** A version of printf() that understands %lld.  Used for debugging.
1014 ** The printf() built into some versions of windows does not understand %lld
1015 ** and segfaults if you give it a long long int.
1016 */
1017 void sqlite3DebugPrintf(const char *zFormat, ...){
1018   va_list ap;
1019   StrAccum acc;
1020   char zBuf[500];
1021   sqlite3StrAccumInit(&acc, zBuf, sizeof(zBuf), 0);
1022   acc.useMalloc = 0;
1023   va_start(ap,zFormat);
1024   sqlite3VXPrintf(&acc, 0, zFormat, ap);
1025   va_end(ap);
1026   sqlite3StrAccumFinish(&acc);
1027   fprintf(stdout,"%s", zBuf);
1028   fflush(stdout);
1029 }
1030 #endif
1031 
1032 /*
1033 ** variable-argument wrapper around sqlite3VXPrintf().
1034 */
1035 void sqlite3XPrintf(StrAccum *p, u32 bFlags, const char *zFormat, ...){
1036   va_list ap;
1037   va_start(ap,zFormat);
1038   sqlite3VXPrintf(p, bFlags, zFormat, ap);
1039   va_end(ap);
1040 }
1041