sys/src/libc/fmt/fmtquote.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include "fmtdef.h"
   4
   5 /*
   6  * How many bytes of output UTF will be produced by quoting (if necessary) this string?
   7  * How many runes? How much of the input will be consumed?
   8  * The parameter q is filled in by _quotesetup.
   9  * The string may be UTF or Runes (s or r).
  10  * Return count does not include NUL.
  11  * Terminate the scan at the first of:
  12  *      NUL in input
  13  *      count exceeded in input
  14  *      count exceeded on output
  15  * *ninp is set to number of input bytes accepted.
  16  * nin may be <0 initially, to avoid checking input by count.
  17  */
  18 void
  19 _quotesetup(char *s, Rune *r, int nin, int nout, Quoteinfo *q, int sharp, int runesout)
  20 {
  21         int w;
  22         Rune c;
  23
  24         q->quoted = 0;
  25         q->nbytesout = 0;
  26         q->nrunesout = 0;
  27         q->nbytesin = 0;
  28         q->nrunesin = 0;
  29         if(sharp || nin==0 || (s && *s=='\0') || (r && *r=='\0')){
  30                 if(nout < 2)
  31                         return;
  32                 q->quoted = 1;
  33                 q->nbytesout = 2;
  34                 q->nrunesout = 2;
  35         }
  36         for(; nin!=0; nin--){
  37                 if(s)
  38                         w = chartorune(&c, s);
  39                 else{
  40                         c = *r;
  41                         w = runelen(c);
  42                 }
  43
  44                 if(c == '\0')
  45                         break;
  46                 if(runesout){
  47                         if(q->nrunesout+1 > nout)
  48                                 break;
  49                 }else{
  50                         if(q->nbytesout+w > nout)
  51                                 break;
  52                 }
  53
  54                 if((c <= L' ') || (c == L'\'') || (doquote!=nil && doquote(c))){
  55                         if(!q->quoted){
  56                                 if(runesout){
  57                                         if(1+q->nrunesout+1+1 > nout)   /* no room for quotes */
  58                                                 break;
  59                                 }else{
  60                                         if(1+q->nbytesout+w+1 > nout)   /* no room for quotes */
  61                                                 break;
  62                                 }
  63                                 q->nrunesout += 2;      /* include quotes */
  64                                 q->nbytesout += 2;      /* include quotes */
  65                                 q->quoted = 1;
  66                         }
  67                         if(c == '\'')   {
  68                                 if(runesout){
  69                                         if(1+q->nrunesout+1 > nout)     /* no room for quotes */
  70                                                 break;
  71                                 }else{
  72                                         if(1+q->nbytesout+w > nout)     /* no room for quotes */
  73                                                 break;
  74                                 }
  75                                 q->nbytesout++;
  76                                 q->nrunesout++; /* quotes reproduce as two characters */
  77                         }
  78                 }
  79
  80                 /* advance input */
  81                 if(s)
  82                         s += w;
  83                 else
  84                         r++;
  85                 q->nbytesin += w;
  86                 q->nrunesin++;
  87
  88                 /* advance output */
  89                 q->nbytesout += w;
  90                 q->nrunesout++;
  91         }
  92 }
  93
  94 static int
  95 qstrfmt(char *sin, Rune *rin, Quoteinfo *q, Fmt *f)
  96 {
  97         Rune r, *rm, *rme;
  98         char *t, *s, *m, *me;
  99         Rune *rt, *rs;
 100         ulong fl;
 101         int nc, w;
 102
 103         m = sin;
 104         me = m + q->nbytesin;
 105         rm = rin;
 106         rme = rm + q->nrunesin;
 107
 108         w = f->width;
 109         fl = f->flags;
 110         if(f->runes){
 111                 if(!(fl & FmtLeft) && _rfmtpad(f, w - q->nrunesout) < 0)
 112                         return -1;
 113         }else{
 114                 if(!(fl & FmtLeft) && _fmtpad(f, w - q->nbytesout) < 0)
 115                         return -1;
 116         }
 117         t = f->to;
 118         s = f->stop;
 119         rt = f->to;
 120         rs = f->stop;
 121         if(f->runes)
 122                 FMTRCHAR(f, rt, rs, '\'');
 123         else
 124                 FMTRUNE(f, t, s, '\'');
 125         for(nc = q->nrunesin; nc > 0; nc--){
 126                 if(sin){
 127                         r = *(uchar*)m;
 128                         if(r < Runeself)
 129                                 m++;
 130                         else if((me - m) >= UTFmax || fullrune(m, me-m))
 131                                 m += chartorune(&r, m);
 132                         else
 133                                 break;
 134                 }else{
 135                         if(rm >= rme)
 136                                 break;
 137                         r = *(uchar*)rm++;
 138                 }
 139                 if(f->runes){
 140                         FMTRCHAR(f, rt, rs, r);
 141                         if(r == '\'')
 142                                 FMTRCHAR(f, rt, rs, r);
 143                 }else{
 144                         FMTRUNE(f, t, s, r);
 145                         if(r == '\'')
 146                                 FMTRUNE(f, t, s, r);
 147                 }
 148         }
 149
 150         if(f->runes){
 151                 FMTRCHAR(f, rt, rs, '\'');
 152                 USED(rs);
 153                 f->nfmt += rt - (Rune *)f->to;
 154                 f->to = rt;
 155                 if(fl & FmtLeft && _rfmtpad(f, w - q->nrunesout) < 0)
 156                         return -1;
 157         }else{
 158                 FMTRUNE(f, t, s, '\'');
 159                 USED(s);
 160                 f->nfmt += t - (char *)f->to;
 161                 f->to = t;
 162                 if(fl & FmtLeft && _fmtpad(f, w - q->nbytesout) < 0)
 163                         return -1;
 164         }
 165         return 0;
 166 }
 167
 168 int
 169 _quotestrfmt(int runesin, Fmt *f)
 170 {
 171         int nin, outlen;
 172         Rune *r;
 173         char *s;
 174         Quoteinfo q;
 175
 176         nin = -1;
 177         if(f->flags&FmtPrec)
 178                 nin = f->prec;
 179         if(runesin){
 180                 r = va_arg(f->args, Rune *);
 181                 s = nil;
 182         }else{
 183                 s = va_arg(f->args, char *);
 184                 r = nil;
 185         }
 186         if(!s && !r)
 187                 return _fmtcpy(f, "<nil>", 5, 5);
 188
 189         if(f->flush)
 190                 outlen = 0x7FFFFFFF;    /* if we can flush, no output limit */
 191         else if(f->runes)
 192                 outlen = (Rune*)f->stop - (Rune*)f->to;
 193         else
 194                 outlen = (char*)f->stop - (char*)f->to;
 195
 196         _quotesetup(s, r, nin, outlen, &q, f->flags&FmtSharp, f->runes);
 197 //print("bytes in %d bytes out %d runes in %d runesout %d\n", q.nbytesin, q.nbytesout, q.nrunesin, q.nrunesout);
 198
 199         if(runesin){
 200                 if(!q.quoted)
 201                         return _fmtrcpy(f, r, q.nrunesin);
 202                 return qstrfmt(nil, r, &q, f);
 203         }
 204
 205         if(!q.quoted)
 206                 return _fmtcpy(f, s, q.nrunesin, q.nbytesin);
 207         return qstrfmt(s, nil, &q, f);
 208 }
 209
 210 int
 211 quotestrfmt(Fmt *f)
 212 {
 213         return _quotestrfmt(0, f);
 214 }
 215
 216 int
 217 quoterunestrfmt(Fmt *f)
 218 {
 219         return _quotestrfmt(1, f);
 220 }
 221
 222 void
 223 quotefmtinstall(void)
 224 {
 225         fmtinstall('q', quotestrfmt);
 226         fmtinstall('Q', quoterunestrfmt);
 227 }
 228
 229 int
 230 _needsquotes(char *s, int *quotelenp)
 231 {
 232         Quoteinfo q;
 233
 234         _quotesetup(s, nil, -1, 0x7FFFFFFF, &q, 0, 0);
 235         *quotelenp = q.nbytesout;
 236
 237         return q.quoted;
 238 }
 239
 240 int
 241 _runeneedsquotes(Rune *r, int *quotelenp)
 242 {
 243         Quoteinfo q;
 244
 245         _quotesetup(nil, r, -1, 0x7FFFFFFF, &q, 0, 0);
 246         *quotelenp = q.nrunesout;
 247
 248         return q.quoted;
 249 }