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