sys/src/cmd/sam/moveto.c

   1 #include "sam.h"
   2
   3 void
   4 moveto(File *f, Range r)
   5 {
   6         Posn p1 = r.p1, p2 = r.p2;
   7
   8         f->dot.r.p1 = p1;
   9         f->dot.r.p2 = p2;
  10         if(f->rasp){
  11                 telldot(f);
  12                 outTsl(Hmoveto, f->tag, f->dot.r.p1);
  13         }
  14 }
  15
  16 void
  17 telldot(File *f)
  18 {
  19         if(f->rasp == 0)
  20                 panic("telldot");
  21         if(f->dot.r.p1==f->tdot.p1 && f->dot.r.p2==f->tdot.p2)
  22                 return;
  23         outTsll(Hsetdot, f->tag, f->dot.r.p1, f->dot.r.p2);
  24         f->tdot = f->dot.r;
  25 }
  26
  27 void
  28 tellpat(void)
  29 {
  30         outTS(Hsetpat, &lastpat);
  31         patset = FALSE;
  32 }
  33
  34 #define CHARSHIFT       128
  35
  36 void
  37 lookorigin(File *f, Posn p0, Posn ls)
  38 {
  39         int nl, nc, c;
  40         Posn p, oldp0;
  41
  42         if(p0 > f->nc)
  43                 p0 = f->nc;
  44         oldp0 = p0;
  45         p = p0;
  46         for(nl=nc=c=0; c!=-1 && nl<ls && nc<ls*CHARSHIFT; nc++)
  47                 if((c=filereadc(f, --p)) == '\n'){
  48                         nl++;
  49                         oldp0 = p0-nc;
  50                 }
  51         if(c == -1)
  52                 p0 = 0;
  53         else if(nl==0){
  54                 if(p0>=CHARSHIFT/2)
  55                         p0-=CHARSHIFT/2;
  56                 else
  57                         p0 = 0;
  58         }else
  59                 p0 = oldp0;
  60         outTsl(Horigin, f->tag, p0);
  61 }
  62
  63 int
  64 alnum(int c)
  65 {
  66         /*
  67          * Hard to get absolutely right.  Use what we know about ASCII
  68          * and assume anything above the Latin control characters is
  69          * potentially an alphanumeric.
  70          */
  71         if(c<=' ')
  72                 return 0;
  73         if(0x7F<=c && c<=0xA0)
  74                 return 0;
  75         if(utfrune("!\"#$%&'()*+,-./:;<=>?@[\\]^`{|}~", c))
  76                 return 0;
  77         return 1;
  78 }
  79
  80 int
  81 clickmatch(File *f, int cl, int cr, int dir, Posn *p)
  82 {
  83         int c;
  84         int nest = 1;
  85
  86         for(;;){
  87                 if(dir > 0){
  88                         if(*p >= f->nc)
  89                                 break;
  90                         c = filereadc(f, (*p)++);
  91                 }else{
  92                         if(*p == 0)
  93                                 break;
  94                         c = filereadc(f, --(*p));
  95                 }
  96                 if(c == cr){
  97                         if(--nest==0)
  98                                 return 1;
  99                 }else if(c == cl)
 100                         nest++;
 101         }
 102         return cl=='\n' && nest==1;
 103 }
 104
 105 Rune*
 106 strrune(Rune *s, Rune c)
 107 {
 108         Rune c1;
 109
 110         if(c == 0) {
 111                 while(*s++)
 112                         ;
 113                 return s-1;
 114         }
 115
 116         while(c1 = *s++)
 117                 if(c1 == c)
 118                         return s-1;
 119         return 0;
 120 }
 121
 122 void
 123 doubleclick(File *f, Posn p1)
 124 {
 125         int c, i;
 126         Rune *r, *l;
 127         Posn p;
 128
 129         if(p1 > f->nc)
 130                 return;
 131         f->dot.r.p1 = f->dot.r.p2 = p1;
 132         for(i=0; left[i]; i++){
 133                 l = left[i];
 134                 r = right[i];
 135                 /* try left match */
 136                 p = p1;
 137                 if(p1 == 0)
 138                         c = '\n';
 139                 else
 140                         c = filereadc(f, p - 1);
 141                 if(strrune(l, c)){
 142                         if(clickmatch(f, c, r[strrune(l, c)-l], 1, &p)){
 143                                 f->dot.r.p1 = p1;
 144                                 f->dot.r.p2 = p-(c!='\n');
 145                         }
 146                         return;
 147                 }
 148                 /* try right match */
 149                 p = p1;
 150                 if(p1 == f->nc)
 151                         c = '\n';
 152                 else
 153                         c = filereadc(f, p);
 154                 if(strrune(r, c)){
 155                         if(clickmatch(f, c, l[strrune(r, c)-r], -1, &p)){
 156                                 f->dot.r.p1 = p;
 157                                 if(c!='\n' || p!=0 || filereadc(f, 0)=='\n')
 158                                         f->dot.r.p1++;
 159                                 f->dot.r.p2 = p1+(p1<f->nc && c=='\n');
 160                         }
 161                         return;
 162                 }
 163         }
 164         /* try filling out word to right */
 165         p = p1;
 166         while(p < f->nc && alnum(filereadc(f, p++)))
 167                 f->dot.r.p2++;
 168         /* try filling out word to left */
 169         p = p1;
 170         while(--p >= 0 && alnum(filereadc(f, p)))
 171                 f->dot.r.p1--;
 172 }
 173