sys/src/libc/port/encodefmt.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <ctype.h>
   4
   5 int
   6 encodefmt(Fmt *f)
   7 {
   8         char *out;
   9         char *buf;
  10         int len;
  11         int ilen;
  12         int rv;
  13         uchar *b;
  14         char *p;
  15         char obuf[64];  // rsc optimization
  16
  17         if(!(f->flags&FmtPrec) || f->prec < 1)
  18                 goto error;
  19
  20         b = va_arg(f->args, uchar*);
  21         if(b == 0)
  22                 return fmtstrcpy(f, "<nil>");
  23
  24         ilen = f->prec;
  25         f->prec = 0;
  26         f->flags &= ~FmtPrec;
  27         switch(f->r){
  28         case '<':
  29                 len = (8*ilen+4)/5 + 3;
  30                 break;
  31         case '[':
  32                 len = (8*ilen+5)/6 + 4;
  33                 break;
  34         case 'H':
  35                 len = 2*ilen + 1;
  36                 break;
  37         default:
  38                 goto error;
  39         }
  40
  41         if(len > sizeof(obuf)){
  42                 buf = malloc(len);
  43                 if(buf == nil)
  44                         goto error;
  45         } else
  46                 buf = obuf;
  47
  48         // convert
  49         out = buf;
  50         switch(f->r){
  51         case '<':
  52                 rv = enc32(out, len, b, ilen);
  53                 break;
  54         case '[':
  55                 rv = enc64(out, len, b, ilen);
  56                 break;
  57         case 'H':
  58                 rv = enc16(out, len, b, ilen);
  59                 if(rv >= 0 && (f->flags & FmtLong))
  60                         for(p = buf; *p; p++)
  61                                 *p = tolower(*p);
  62                 break;
  63         default:
  64                 rv = -1;
  65                 break;
  66         }
  67         if(rv < 0)
  68                 goto error;
  69
  70         fmtstrcpy(f, buf);
  71         if(buf != obuf)
  72                 free(buf);
  73         return 0;
  74
  75 error:
  76         return fmtstrcpy(f, "<encodefmt>");
  77 }