1 #include <u.h>
2 #include <libc.h>
3 #include <draw.h>
4 
5 static int	fontresize(Font*, int, int, int);
6 #if 0
7 static int	freeup(Font*);
8 #endif
9 
10 #define	PJW	0	/* use NUL==pjw for invisible characters */
11 
12 static Rune empty[] = { 0 };
13 int
14 cachechars(Font *f, char **ss, Rune **rr, ushort *cp, int max, int *wp, char **subfontname)
15 {
16 	int i, th, sh, h, ld, w, rw, wid, nc;
17 	char *sp;
18 	Rune r, *rp, vr;
19 	ulong a;
20 	Cacheinfo *c, *tc, *ec;
21 
22 	if(ss){
23 		sp = *ss;
24 		rp = empty;
25 	}else{
26 		sp = "";
27 		rp = *rr;
28 	}
29 	wid = 0;
30 	*subfontname = 0;
31 	for(i=0; i<max && (*sp || *rp); sp+=w, rp+=rw){
32 		if(ss){
33 			r = *(uchar*)sp;
34 			if(r < Runeself)
35 				w = 1;
36 			else{
37 				w = chartorune(&vr, sp);
38 				r = vr;
39 			}
40 			rw = 0;
41 		}else{
42 			r = *rp;
43 			w = 0;
44 			rw = 1;
45 		}
46 
47 		sh = (17 * (uint)r) & (f->ncache-NFLOOK-1);
48 		c = &f->cache[sh];
49 		ec = c+NFLOOK;
50 		h = sh;
51 		while(c < ec){
52 			if(c->value==r && c->age)
53 				goto Found;
54 			c++;
55 			h++;
56 		}
57 	
58 		/*
59 		 * Not found; toss out oldest entry
60 		 */
61 		a = ~0;
62 		th = sh;
63 		tc = &f->cache[th];
64 		while(tc < ec){
65 			if(tc->age < a){
66 				a = tc->age;
67 				h = th;
68 				c = tc;
69 			}
70 			tc++;
71 			th++;
72 		}
73 
74 		if(a && (f->age-a)<500){	/* kicking out too recent; resize */
75 			nc = 2*(f->ncache-NFLOOK) + NFLOOK;
76 			if(nc <= MAXFCACHE){
77 				if(i == 0)
78 					fontresize(f, f->width, nc, f->maxdepth);
79 				/* else flush first; retry will resize */
80 				break;
81 			}
82 		}
83 
84 		if(c->age == f->age)	/* flush pending string output */
85 			break;
86 
87 		ld = loadchar(f, r, c, h, i, subfontname);
88 		if(ld <= 0){
89 			if(ld == 0)
90 				continue;
91 			break;
92 		}
93 		c = &f->cache[h];	/* may have reallocated f->cache */
94 	
95 	    Found:
96 		wid += c->width;
97 		c->age = f->age;
98 		cp[i] = h;
99 		i++;
100 	}
101 	if(ss)
102 		*ss = sp;
103 	else
104 		*rr = rp;
105 	*wp = wid;
106 	return i;
107 }
108 
109 void
110 agefont(Font *f)
111 {
112 	Cacheinfo *c, *ec;
113 	Cachesubf *s, *es;
114 
115 	f->age++;
116 	if(f->age == 65536){
117 		/*
118 		 * Renormalize ages
119 		 */
120 		c = f->cache;
121 		ec = c+f->ncache;
122 		while(c < ec){
123 			if(c->age){
124 				c->age >>= 2;
125 				c->age++;
126 			}
127 			c++;
128 		}
129 		s = f->subf;
130 		es = s+f->nsubf;
131 		while(s < es){
132 			if(s->age){
133 				if(s->age<SUBFAGE && s->cf->name != nil){
134 					/* clean up */
135 					if(display==nil || s->f != display->defaultsubfont)
136 						freesubfont(s->f);
137 					s->cf = nil;
138 					s->f = nil;
139 					s->age = 0;
140 				}else{
141 					s->age >>= 2;
142 					s->age++;
143 				}
144 			}
145 			s++;
146 		}
147 		f->age = (65536>>2) + 1;
148 	}
149 }
150 
151 static Subfont*
152 cf2subfont(Cachefont *cf, Font *f)
153 {
154 	int depth;
155 	char *name;
156 	Subfont *sf;
157 
158 	name = cf->subfontname;
159 	if(name == nil){
160 		depth = 0;
161 		if(f->display){
162 			if(f->display->screenimage)
163 				depth = f->display->screenimage->depth;
164 		}else
165 			depth = 8;
166 		name = subfontname(cf->name, f->name, depth);
167 		if(name == nil)
168 			return nil;
169 		cf->subfontname = name;
170 	}
171 	sf = lookupsubfont(f->display, name);
172 	return sf;
173 }
174 
175 /* return 1 if load succeeded, 0 if failed, -1 if must retry */
176 int
177 loadchar(Font *f, Rune r, Cacheinfo *c, int h, int noflush, char **subfontname)
178 {
179 	int i, oi, wid, top, bottom;
180 	int pic;	/* need >16 bits for adding offset below */
181 	Fontchar *fi;
182 	Cachefont *cf;
183 	Cachesubf *subf, *of;
184 	uchar *b;
185 
186 	pic = r;
187     Again:
188 	for(i=0; i<f->nsub; i++){
189 		cf = f->sub[i];
190 		if(cf->min<=pic && pic<=cf->max)
191 			goto Found;
192 	}
193     TryPJW:
194 	if(pic != PJW){
195 		pic = PJW;
196 		goto Again;
197 	}
198 	return 0;
199 
200     Found:
201 	/*
202 	 * Choose exact or oldest
203 	 */
204 	oi = 0;
205 	subf = &f->subf[0];
206 	for(i=0; i<f->nsubf; i++){
207 		if(cf == subf->cf)
208 			goto Found2;
209 		if(subf->age < f->subf[oi].age)
210 			oi = i;
211 		subf++;
212 	}
213 	subf = &f->subf[oi];
214 
215 	if(subf->f){
216 		if(f->age-subf->age>SUBFAGE || f->nsubf>MAXSUBF){
217     Toss:
218 			/* ancient data; toss */
219 			freesubfont(subf->f);
220 			subf->cf = nil;
221 			subf->f = nil;
222 			subf->age = 0;
223 		}else{				/* too recent; grow instead */
224 			of = f->subf;
225 			f->subf = malloc((f->nsubf+DSUBF)*sizeof *subf);
226 			if(f->subf == nil){
227 				f->subf = of;
228 				goto Toss;
229 			}
230 			memmove(f->subf, of, (f->nsubf+DSUBF)*sizeof *subf);
231 			memset(f->subf+f->nsubf, 0, DSUBF*sizeof *subf);
232 			subf = &f->subf[f->nsubf];
233 			f->nsubf += DSUBF;
234 			free(of);
235 		}
236 	}
237 	subf->age = 0;
238 	subf->cf = nil;
239 	subf->f = cf2subfont(cf, f);
240 	if(subf->f == nil){
241 		if(cf->subfontname == nil)
242 			goto TryPJW;
243 		*subfontname = cf->subfontname;
244 		return -1;
245 	}
246 
247 	subf->cf = cf;
248 	if(subf->f->ascent > f->ascent && f->display){
249 		/* should print something? this is a mistake in the font file */
250 		/* must prevent c->top from going negative when loading cache */
251 		Image *b;
252 		int d, t;
253 		d = subf->f->ascent - f->ascent;
254 		b = subf->f->bits;
255 		draw(b, b->r, b, nil, addpt(b->r.min, Pt(0, d)));
256 		draw(b, Rect(b->r.min.x, b->r.max.y-d, b->r.max.x, b->r.max.y), f->display->black, nil, b->r.min);
257 		for(i=0; i<subf->f->n; i++){
258 			t = subf->f->info[i].top-d;
259 			if(t < 0)
260 				t = 0;
261 			subf->f->info[i].top = t;
262 			t = subf->f->info[i].bottom-d;
263 			if(t < 0)
264 				t = 0;
265 			subf->f->info[i].bottom = t;
266 		}
267 		subf->f->ascent = f->ascent;
268 	}
269 
270     Found2:
271 	subf->age = f->age;
272 
273 	/* possible overflow here, but works out okay */
274 	pic += cf->offset;
275 	pic -= cf->min;
276 	if(pic >= subf->f->n)
277 		goto TryPJW;
278 	fi = &subf->f->info[pic];
279 	if(fi->width == 0)
280 		goto TryPJW;
281 	wid = (fi+1)->x - fi->x;
282 	if(f->width < wid || f->width == 0 || f->maxdepth < subf->f->bits->depth){
283 		/*
284 		 * Flush, free, reload (easier than reformatting f->b)
285 		 */
286 		if(noflush)
287 			return -1;
288 		if(f->width < wid)
289 			f->width = wid;
290 		if(f->maxdepth < subf->f->bits->depth)
291 			f->maxdepth = subf->f->bits->depth;
292 		i = fontresize(f, f->width, f->ncache, f->maxdepth);
293 		if(i <= 0)
294 			return i;
295 		/* c is still valid as didn't reallocate f->cache */
296 	}
297 	c->value = r;
298 	top = fi->top + (f->ascent-subf->f->ascent);
299 	bottom = fi->bottom + (f->ascent-subf->f->ascent);
300 	c->width = fi->width;
301 	c->x = h*f->width;
302 	c->left = fi->left;
303 	if(f->display == nil)
304 		return 1;
305 	flushimage(f->display, 0);	/* flush any pending errors */
306 	b = bufimage(f->display, 37);
307 	if(b == 0)
308 		return 0;
309 	b[0] = 'l';
310 	BPLONG(b+1, f->cacheimage->id);
311 	BPLONG(b+5, subf->f->bits->id);
312 	BPSHORT(b+9, c-f->cache);
313 	BPLONG(b+11, c->x);
314 	BPLONG(b+15, top);
315 	BPLONG(b+19, c->x+((fi+1)->x-fi->x));
316 	BPLONG(b+23, bottom);
317 	BPLONG(b+27, fi->x);
318 	BPLONG(b+31, fi->top);
319 	b[35] = fi->left;
320 	b[36] = fi->width;
321 	return 1;
322 }
323 
324 /* release all subfonts, return number freed */
325 #if 0
326 static
327 int
328 freeup(Font *f)
329 {
330 	Cachesubf *s, *es;
331 	int nf;
332 
333 	if(f->sub[0]->name == nil)	/* font from mkfont; don't free */
334 		return 0;
335 	s = f->subf;
336 	es = s+f->nsubf;
337 	nf = 0;
338 	while(s < es){
339 		if(s->age){
340 			freesubfont(s->f);
341 			s->cf = nil;
342 			s->f = nil;
343 			s->age = 0;
344 			nf++;
345 		}
346 		s++;
347 	}
348 	return nf;
349 }
350 #endif
351 
352 /* return whether resize succeeded && f->cache is unchanged */
353 static int
354 fontresize(Font *f, int wid, int ncache, int depth)
355 {
356 	Cacheinfo *i;
357 	int ret;
358 	Image *new;
359 	uchar *b;
360 	Display *d;
361 
362 	ret = 0;
363 	if(depth <= 0)
364 		depth = 1;
365 
366 	d = f->display;
367 	if(d == nil)
368 		goto Nodisplay;
369 
370 	new = allocimage(d, Rect(0, 0, ncache*wid, f->height), CHAN1(CGrey, depth), 0, 0);
371 	if(new == nil){
372 		fprint(2, "font cache resize failed: %r\n");
373 		abort();
374 		goto Return;
375 	}
376 	flushimage(d, 0);	/* flush any pending errors */
377 	b = bufimage(d, 1+4+4+1);
378 	if(b == 0){
379 		freeimage(new);
380 		goto Return;
381 	}
382 	b[0] = 'i';
383 	BPLONG(b+1, new->id);
384 	BPLONG(b+5, ncache);
385 	b[9] = f->ascent;
386 	if(flushimage(d, 0) < 0){
387 		fprint(2, "resize: init failed: %r\n");
388 		freeimage(new);
389 		goto Return;
390 	}
391 	freeimage(f->cacheimage);
392 	f->cacheimage = new;
393     Nodisplay:
394 	f->width = wid;
395 	f->maxdepth = depth;
396 	ret = 1;
397 	if(f->ncache != ncache){
398 		i = malloc(ncache*sizeof f->cache[0]);
399 		if(i != nil){
400 			ret = 0;
401 			free(f->cache);
402 			f->ncache = ncache;
403 			f->cache = i;
404 		}
405 		/* else just wipe the cache clean and things will be ok */
406 	}
407     Return:
408 	memset(f->cache, 0, f->ncache*sizeof f->cache[0]);
409 	return ret;
410 }