sys/src/cmd/htmlroff/char.c

   1 #include "a.h"
   2
   3 /*
   4  * Translate Unicode to HTML by asking tcs(1).
   5  * This way we don't have yet another table.
   6  */
   7 Rune*
   8 rune2html(Rune r)
   9 {
  10         static Biobuf b;
  11         static int fd = -1;
  12         static Rune **tcscache[256];
  13         int p[2];
  14         char *q;
  15
  16         if(r == '\n')
  17                 return L("\n");
  18
  19         if(((uint)r&~0xFFFF) != 0){
  20                 /* The cache must grow a lot to handle them */
  21                 fprint(2, "%s: can't handle rune '%C'\n", argv0, r);
  22                 return L("?");
  23         }
  24
  25         if(tcscache[r>>8] && tcscache[r>>8][r&0xFF])
  26                 return tcscache[r>>8][r&0xFF];
  27
  28         if(fd < 0){
  29                 if(pipe(p) < 0)
  30                         sysfatal("pipe: %r");
  31                 switch(fork()){
  32                 case -1:
  33                         sysfatal("fork: %r");
  34                 case 0:
  35                         dup(p[0], 0);
  36                         dup(p[1], 1);
  37                         close(p[0]);
  38                         close(p[1]);
  39                         execl("/bin/tcs", "tcs", "-t", "html", nil);
  40                         _exits(0);
  41                 default:
  42                         fd = p[1];
  43                         Binit(&b, p[0], OREAD);
  44                         break;
  45                 }
  46         }
  47         /* HACK: extra newlines force rune+\n through tcs now */
  48         fprint(fd, "%C\n\n\n\n", r);
  49         q = Brdline(&b, '\n');
  50         while (q != nil && *q == '\n')
  51                 q = Brdline(&b, '\n');
  52         if(q == nil)
  53                 sysfatal("tcs: early eof");
  54         q[Blinelen(&b)-1] = 0;
  55         if(tcscache[r>>8] == nil)
  56                 tcscache[r>>8] = emalloc(256*sizeof tcscache[0][0]);
  57         tcscache[r>>8][r&0xFF] = erunesmprint("%s", q);
  58         return tcscache[r>>8][r&0xFF];
  59 }
  60
  61 /*
  62  * Translate troff to Unicode by looking in troff's utfmap.
  63  * This way we don't have yet another hard-coded table.
  64  */
  65 typedef struct Trtab Trtab;
  66 struct Trtab
  67 {
  68         char t[UTFmax];
  69         Rune r;
  70 };
  71
  72 static Trtab trtab[200];
  73 int ntrtab;
  74
  75 static Trtab trinit[] =
  76 {
  77         "pl",           Upl,
  78         "eq",   Ueq,
  79         "em",   0x2014,
  80         "en",   0x2013,
  81         "mi",   Umi,
  82         "fm",   0x2032,
  83 };
  84
  85 Rune
  86 troff2rune(Rune *rs)
  87 {
  88         char *file, *f[10], *p, s[3];
  89         int i, nf;
  90         Biobuf *b;
  91
  92         if(rs[0] >= Runeself || rs[1] >= Runeself)
  93                 return Runeerror;
  94         s[0] = rs[0];
  95         s[1] = rs[1];
  96         s[2] = 0;
  97         if(ntrtab == 0){
  98                 for(i=0; i<nelem(trinit) && ntrtab < nelem(trtab); i++){
  99                         trtab[ntrtab] = trinit[i];
 100                         ntrtab++;
 101                 }
 102                 file = "/sys/lib/troff/font/devutf/utfmap";
 103                 if((b = Bopen(file, OREAD)) == nil)
 104                         sysfatal("open %s: %r", file);
 105                 while((p = Brdline(b, '\n')) != nil){
 106                         p[Blinelen(b)-1] = 0;
 107                         nf = getfields(p, f, nelem(f), 0, "\t");
 108                         for(i=0; i+2<=nf && ntrtab<nelem(trtab); i+=2){
 109                                 chartorune(&trtab[ntrtab].r, f[i]);
 110                                 memmove(trtab[ntrtab].t, f[i+1], 2);
 111                                 ntrtab++;
 112                         }
 113                 }
 114                 Bterm(b);
 115
 116                 if(ntrtab >= nelem(trtab))
 117                         fprint(2, "%s: trtab too small\n", argv0);
 118         }
 119
 120         for(i=0; i<ntrtab; i++)
 121                 if(strcmp(s, trtab[i].t) == 0)
 122                         return trtab[i].r;
 123         return Runeerror;
 124 }
 125