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; (*sp || *rp) && i<max; 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(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 		}
165 		name = subfontname(cf->name, f->name, depth);
166 		if(name == nil)
167 			return nil;
168 		cf->subfontname = name;
169 	}
170 	sf = lookupsubfont(f->display, name);
171 	return sf;
172 }
173 
174 /* return 1 if load succeeded, 0 if failed, -1 if must retry */
175 int
176 loadchar(Font *f, Rune r, Cacheinfo *c, int h, int noflush, char **subfontname)
177 {
178 	int i, oi, wid, top, bottom;
179 	Rune pic;
180 	Fontchar *fi;
181 	Cachefont *cf;
182 	Cachesubf *subf, *of;
183 	uchar *b;
184 
185 	pic = r;
186     Again:
187 	for(i=0; i<f->nsub; i++){
188 		cf = f->sub[i];
189 		if(cf->min<=pic && pic<=cf->max)
190 			goto Found;
191 	}
192     TryPJW:
193 	if(pic != PJW){
194 		pic = PJW;
195 		goto Again;
196 	}
197 	return 0;
198 
199     Found:
200 	/*
201 	 * Choose exact or oldest
202 	 */
203 	oi = 0;
204 	subf = &f->subf[0];
205 	for(i=0; i<f->nsubf; i++){
206 		if(cf == subf->cf)
207 			goto Found2;
208 		if(subf->age < f->subf[oi].age)
209 			oi = i;
210 		subf++;
211 	}
212 	subf = &f->subf[oi];
213 
214 	if(subf->f){
215 		if(f->age-subf->age>SUBFAGE || f->nsubf>MAXSUBF){
216     Toss:
217 			/* ancient data; toss */
218 			freesubfont(subf->f);
219 			subf->cf = nil;
220 			subf->f = nil;
221 			subf->age = 0;
222 		}else{				/* too recent; grow instead */
223 			of = f->subf;
224 			f->subf = malloc((f->nsubf+DSUBF)*sizeof *subf);
225 			if(f->subf == nil){
226 				f->subf = of;
227 				goto Toss;
228 			}
229 			memmove(f->subf, of, (f->nsubf+DSUBF)*sizeof *subf);
230 			memset(f->subf+f->nsubf, 0, DSUBF*sizeof *subf);
231 			subf = &f->subf[f->nsubf];
232 			f->nsubf += DSUBF;
233 			free(of);
234 		}
235 	}
236 	subf->age = 0;
237 	subf->cf = nil;
238 	subf->f = cf2subfont(cf, f);
239 	if(subf->f == nil){
240 		if(cf->subfontname == nil)
241 			goto TryPJW;
242 		*subfontname = cf->subfontname;
243 		return -1;
244 	}
245 
246 	subf->cf = cf;
247 	if(subf->f->ascent > f->ascent){
248 		/* should print something? this is a mistake in the font file */
249 		/* must prevent c->top from going negative when loading cache */
250 		Image *b;
251 		int d, t;
252 		d = subf->f->ascent - f->ascent;
253 		b = subf->f->bits;
254 		draw(b, b->r, b, nil, addpt(b->r.min, Pt(0, d)));
255 		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);
256 		for(i=0; i<subf->f->n; i++){
257 			t = subf->f->info[i].top-d;
258 			if(t < 0)
259 				t = 0;
260 			subf->f->info[i].top = t;
261 			t = subf->f->info[i].bottom-d;
262 			if(t < 0)
263 				t = 0;
264 			subf->f->info[i].bottom = t;
265 		}
266 		subf->f->ascent = f->ascent;
267 	}
268 
269     Found2:
270 	subf->age = f->age;
271 
272 	pic += cf->offset;
273 	if(pic-cf->min >= subf->f->n)
274 		goto TryPJW;
275 	fi = &subf->f->info[pic - cf->min];
276 	if(fi->width == 0)
277 		goto TryPJW;
278 	wid = (fi+1)->x - fi->x;
279 	if(f->width < wid || f->width == 0 || f->maxdepth < subf->f->bits->depth){
280 		/*
281 		 * Flush, free, reload (easier than reformatting f->b)
282 		 */
283 		if(noflush)
284 			return -1;
285 		if(f->width < wid)
286 			f->width = wid;
287 		if(f->maxdepth < subf->f->bits->depth)
288 			f->maxdepth = subf->f->bits->depth;
289 		i = fontresize(f, f->width, f->ncache, f->maxdepth);
290 		if(i <= 0)
291 			return i;
292 		/* c is still valid as didn't reallocate f->cache */
293 	}
294 	c->value = r;
295 	top = fi->top + (f->ascent-subf->f->ascent);
296 	bottom = fi->bottom + (f->ascent-subf->f->ascent);
297 	c->width = fi->width;
298 	c->x = h*f->width;
299 	c->left = fi->left;
300 	flushimage(f->display, 0);	/* flush any pending errors */
301 	b = bufimage(f->display, 37);
302 	if(b == 0)
303 		return 0;
304 	b[0] = 'l';
305 	BPLONG(b+1, f->cacheimage->id);
306 	BPLONG(b+5, subf->f->bits->id);
307 	BPSHORT(b+9, c-f->cache);
308 	BPLONG(b+11, c->x);
309 	BPLONG(b+15, top);
310 	BPLONG(b+19, c->x+((fi+1)->x-fi->x));
311 	BPLONG(b+23, bottom);
312 	BPLONG(b+27, fi->x);
313 	BPLONG(b+31, fi->top);
314 	b[35] = fi->left;
315 	b[36] = fi->width;
316 	return 1;
317 }
318 
319 /* release all subfonts, return number freed */
320 #if 0
321 static
322 int
323 freeup(Font *f)
324 {
325 	Cachesubf *s, *es;
326 	int nf;
327 
328 	if(f->sub[0]->name == nil)	/* font from mkfont; don't free */
329 		return 0;
330 	s = f->subf;
331 	es = s+f->nsubf;
332 	nf = 0;
333 	while(s < es){
334 		if(s->age){
335 			freesubfont(s->f);
336 			s->cf = nil;
337 			s->f = nil;
338 			s->age = 0;
339 			nf++;
340 		}
341 		s++;
342 	}
343 	return nf;
344 }
345 #endif
346 
347 /* return whether resize succeeded && f->cache is unchanged */
348 static int
349 fontresize(Font *f, int wid, int ncache, int depth)
350 {
351 	Cacheinfo *i;
352 	int ret;
353 	Image *new;
354 	uchar *b;
355 	Display *d;
356 
357 	ret = 0;
358 	d = f->display;
359 	if(depth <= 0)
360 		depth = 1;
361 
362 	new = allocimage(d, Rect(0, 0, ncache*wid, f->height), CHAN1(CGrey, depth), 0, 0);
363 	if(new == nil){
364 		fprint(2, "font cache resize failed: %r\n");
365 		abort();
366 		goto Return;
367 	}
368 	flushimage(d, 0);	/* flush any pending errors */
369 	b = bufimage(d, 1+4+4+1);
370 	if(b == 0){
371 		freeimage(new);
372 		goto Return;
373 	}
374 	b[0] = 'i';
375 	BPLONG(b+1, new->id);
376 	BPLONG(b+5, ncache);
377 	b[9] = f->ascent;
378 	if(flushimage(d, 0) < 0){
379 		fprint(2, "resize: init failed: %r\n");
380 		freeimage(new);
381 		goto Return;
382 	}
383 	freeimage(f->cacheimage);
384 	f->cacheimage = new;
385 	f->width = wid;
386 	f->maxdepth = depth;
387 	ret = 1;
388 	if(f->ncache != ncache){
389 		i = malloc(ncache*sizeof f->cache[0]);
390 		if(i != nil){
391 			ret = 0;
392 			free(f->cache);
393 			f->ncache = ncache;
394 			f->cache = i;
395 		}
396 		/* else just wipe the cache clean and things will be ok */
397 	}
398     Return:
399 	memset(f->cache, 0, f->ncache*sizeof f->cache[0]);
400 	return ret;
401 }