1 /*
2  * scale.c - deal with server-side scaling.
3  */
4 
5 /*
6  *  Copyright (C) 2005 Rohit Kumar, Johannes E. Schindelin
7  *  Copyright (C) 2002 RealVNC Ltd.
8  *  OSXvnc Copyright (C) 2001 Dan McGuirk <mcguirk@incompleteness.net>.
9  *  Original Xvnc code Copyright (C) 1999 AT&T Laboratories Cambridge.
10  *  All Rights Reserved.
11  *
12  *  This is free software; you can redistribute it and/or modify
13  *  it under the terms of the GNU General Public License as published by
14  *  the Free Software Foundation; either version 2 of the License, or
15  *  (at your option) any later version.
16  *
17  *  This software is distributed in the hope that it will be useful,
18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *  GNU General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License
23  *  along with this software; if not, write to the Free Software
24  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
25  *  USA.
26  */
27 
28 #ifdef __STRICT_ANSI__
29 #define _BSD_SOURCE
30 #endif
31 #include <string.h>
32 #include <rfb/rfb.h>
33 #include <rfb/rfbregion.h>
34 #include "private.h"
35 
36 #ifdef LIBVNCSERVER_HAVE_FCNTL_H
37 #include <fcntl.h>
38 #endif
39 
40 #ifdef WIN32
41 #define write(sock,buf,len) send(sock,buf,len,0)
42 #else
43 #ifdef LIBVNCSERVER_HAVE_UNISTD_H
44 #include <unistd.h>
45 #endif
46 #include <pwd.h>
47 #ifdef LIBVNCSERVER_HAVE_SYS_SOCKET_H
48 #include <sys/socket.h>
49 #endif
50 #ifdef LIBVNCSERVER_HAVE_NETINET_IN_H
51 #include <netinet/in.h>
52 #include <netinet/tcp.h>
53 #include <arpa/inet.h>
54 #endif
55 #endif
56 
57 #ifdef DEBUGPROTO
58 #undef DEBUGPROTO
59 #define DEBUGPROTO(x) x
60 #else
61 #define DEBUGPROTO(x)
62 #endif
63 
64 /****************************/
65 #define CEIL(x)  ( (double) ((int) (x)) == (x) ? \
66         (double) ((int) (x)) : (double) ((int) (x) + 1) )
67 #define FLOOR(x) ( (double) ((int) (x)) )
68 
69 
ScaleX(rfbScreenInfoPtr from,rfbScreenInfoPtr to,int x)70 int ScaleX(rfbScreenInfoPtr from, rfbScreenInfoPtr to, int x)
71 {
72     if ((from==to) || (from==NULL) || (to==NULL)) return x;
73     return ((int)(((double) x / (double)from->width) * (double)to->width ));
74 }
75 
ScaleY(rfbScreenInfoPtr from,rfbScreenInfoPtr to,int y)76 int ScaleY(rfbScreenInfoPtr from, rfbScreenInfoPtr to, int y)
77 {
78     if ((from==to) || (from==NULL) || (to==NULL)) return y;
79     return ((int)(((double) y / (double)from->height) * (double)to->height ));
80 }
81 
82 /* So, all of the encodings point to the ->screen->frameBuffer,
83  * We need to change this!
84  */
rfbScaledCorrection(rfbScreenInfoPtr from,rfbScreenInfoPtr to,int * x,int * y,int * w,int * h,const char * function)85 void rfbScaledCorrection(rfbScreenInfoPtr from, rfbScreenInfoPtr to, int *x, int *y, int *w, int *h, const char *function)
86 {
87     double x1,y1,w1,h1, x2, y2, w2, h2;
88     double scaleW = ((double) to->width) / ((double) from->width);
89     double scaleH = ((double) to->height) / ((double) from->height);
90 
91 
92     /*
93      * rfbLog("rfbScaledCorrection(%p -> %p, %dx%d->%dx%d (%dXx%dY-%dWx%dH)\n",
94      * from, to, from->width, from->height, to->width, to->height, *x, *y, *w, *h);
95      */
96 
97     /* If it's the original framebuffer... */
98     if (from==to) return;
99 
100     x1 = ((double) *x) * scaleW;
101     y1 = ((double) *y) * scaleH;
102     w1 = ((double) *w) * scaleW;
103     h1 = ((double) *h) * scaleH;
104 
105 
106     /*cast from double to int is same as "*x = floor(x1);" */
107     x2 = FLOOR(x1);
108     y2 = FLOOR(y1);
109 
110     /* include into W and H the jitter of scaling X and Y */
111     w2 = CEIL(w1 + ( x1 - x2 ));
112     h2 = CEIL(h1 + ( y1 - y2 ));
113 
114     /*
115      * rfbLog("%s (%dXx%dY-%dWx%dH  ->  %fXx%fY-%fWx%fH) {%dWx%dH -> %dWx%dH}\n",
116      *    function, *x, *y, *w, *h, x2, y2, w2, h2,
117      *    from->width, from->height, to->width, to->height);
118      */
119 
120     /* simulate ceil() without math library */
121     *x = (int)x2;
122     *y = (int)y2;
123     *w = (int)w2;
124     *h = (int)h2;
125 
126     /* Small changes for a thumbnail may be scaled to zero */
127     if (*w==0) (*w)++;
128     if (*h==0) (*h)++;
129     /* scaling from small to big may overstep the size a bit */
130     if (*x+*w > to->width)  *w=to->width - *x;
131     if (*y+*h > to->height) *h=to->height - *y;
132 }
133 
rfbScaledScreenUpdateRect(rfbScreenInfoPtr screen,rfbScreenInfoPtr ptr,int x0,int y0,int w0,int h0)134 void rfbScaledScreenUpdateRect(rfbScreenInfoPtr screen, rfbScreenInfoPtr ptr, int x0, int y0, int w0, int h0)
135 {
136     int x,y,w,v,z;
137     int x1, y1, w1, h1;
138     int bitsPerPixel, bytesPerPixel, bytesPerLine, areaX, areaY, area2;
139     unsigned char *srcptr, *dstptr;
140 
141     /* Nothing to do!!! */
142     if (screen==ptr) return;
143 
144     x1 = x0;
145     y1 = y0;
146     w1 = w0;
147     h1 = h0;
148 
149     rfbScaledCorrection(screen, ptr, &x1, &y1, &w1, &h1, "rfbScaledScreenUpdateRect");
150     x0 = ScaleX(ptr, screen, x1);
151     y0 = ScaleY(ptr, screen, y1);
152     w0 = ScaleX(ptr, screen, w1);
153     h0 = ScaleY(ptr, screen, h1);
154 
155     bitsPerPixel = screen->bitsPerPixel;
156     bytesPerPixel = bitsPerPixel / 8;
157     bytesPerLine = w1 * bytesPerPixel;
158     srcptr = (unsigned char *)(screen->frameBuffer +
159      (y0 * screen->paddedWidthInBytes + x0 * bytesPerPixel));
160     dstptr = (unsigned char *)(ptr->frameBuffer +
161      ( y1 * ptr->paddedWidthInBytes + x1 * bytesPerPixel));
162     /* The area of the source framebuffer for each destination pixel */
163     areaX = ScaleX(ptr,screen,1);
164     areaY = ScaleY(ptr,screen,1);
165     area2 = areaX*areaY;
166 
167 
168     /* Ensure that we do not go out of bounds */
169     if ((x1+w1) > (ptr->width))
170     {
171       if (x1==0) w1=ptr->width; else x1 = ptr->width - w1;
172     }
173     if ((y1+h1) > (ptr->height))
174     {
175       if (y1==0) h1=ptr->height; else y1 = ptr->height - h1;
176     }
177     /*
178      * rfbLog("rfbScaledScreenUpdateRect(%dXx%dY-%dWx%dH  ->  %dXx%dY-%dWx%dH <%dx%d>) {%dWx%dH -> %dWx%dH} 0x%p\n",
179      *    x0, y0, w0, h0, x1, y1, w1, h1, areaX, areaY,
180      *    screen->width, screen->height, ptr->width, ptr->height, ptr->frameBuffer);
181      */
182 
183     if (screen->serverFormat.trueColour) { /* Blend neighbouring pixels together */
184       unsigned char *srcptr2;
185       unsigned long pixel_value, red, green, blue;
186       unsigned int redShift = screen->serverFormat.redShift;
187       unsigned int greenShift = screen->serverFormat.greenShift;
188       unsigned int blueShift = screen->serverFormat.blueShift;
189       unsigned long redMax = screen->serverFormat.redMax;
190       unsigned long greenMax = screen->serverFormat.greenMax;
191       unsigned long blueMax = screen->serverFormat.blueMax;
192 
193      /* for each *destination* pixel... */
194      for (y = 0; y < h1; y++) {
195        for (x = 0; x < w1; x++) {
196          red = green = blue = 0;
197          /* Get the totals for rgb from the source grid... */
198          for (w = 0; w < areaX; w++) {
199            for (v = 0; v < areaY; v++) {
200              srcptr2 = &srcptr[(((x * areaX) + w) * bytesPerPixel) +
201                                (v * screen->paddedWidthInBytes)];
202              pixel_value = 0;
203 
204 
205              switch (bytesPerPixel) {
206              case 4: pixel_value = *((unsigned int *)srcptr2);   break;
207              case 2: pixel_value = *((unsigned short *)srcptr2); break;
208              case 1: pixel_value = *((unsigned char *)srcptr2);  break;
209              default:
210                /* fixme: endianess problem? */
211                for (z = 0; z < bytesPerPixel; z++)
212                  pixel_value += (srcptr2[z] << (8 * z));
213                 break;
214               }
215               /*
216               srcptr2 += bytesPerPixel;
217               */
218 
219             red += ((pixel_value >> redShift) & redMax);
220             green += ((pixel_value >> greenShift) & greenMax);
221             blue += ((pixel_value >> blueShift) & blueMax);
222 
223            }
224          }
225          /* We now have a total for all of the colors, find the average! */
226          red /= area2;
227          green /= area2;
228          blue /= area2;
229           /* Stuff the new value back into memory */
230          pixel_value = ((red & redMax) << redShift) | ((green & greenMax) << greenShift) | ((blue & blueMax) << blueShift);
231 
232          switch (bytesPerPixel) {
233          case 4: *((unsigned int *)dstptr)   = (unsigned int)   pixel_value; break;
234          case 2: *((unsigned short *)dstptr) = (unsigned short) pixel_value; break;
235          case 1: *((unsigned char *)dstptr)  = (unsigned char)  pixel_value; break;
236          default:
237            /* fixme: endianess problem? */
238            for (z = 0; z < bytesPerPixel; z++)
239              dstptr[z]=(pixel_value >> (8 * z)) & 0xff;
240             break;
241           }
242           dstptr += bytesPerPixel;
243        }
244        srcptr += (screen->paddedWidthInBytes * areaY);
245        dstptr += (ptr->paddedWidthInBytes - bytesPerLine);
246      }
247    } else
248    { /* Not truecolour, so we can't blend. Just use the top-left pixel instead */
249      for (y = y1; y < (y1+h1); y++) {
250        for (x = x1; x < (x1+w1); x++)
251          memcpy (&ptr->frameBuffer[(y *ptr->paddedWidthInBytes) + (x * bytesPerPixel)],
252                  &screen->frameBuffer[(y * areaY * screen->paddedWidthInBytes) + (x *areaX * bytesPerPixel)], bytesPerPixel);
253      }
254   }
255 }
256 
rfbScaledScreenUpdate(rfbScreenInfoPtr screen,int x1,int y1,int x2,int y2)257 void rfbScaledScreenUpdate(rfbScreenInfoPtr screen, int x1, int y1, int x2, int y2)
258 {
259     /* ok, now the task is to update each and every scaled version of the framebuffer
260      * and we only have to do this for this specific changed rectangle!
261      */
262     rfbScreenInfoPtr ptr;
263     int count=0;
264 
265     /* We don't point to cl->screen as it is the original */
266     for (ptr=screen->scaledScreenNext;ptr!=NULL;ptr=ptr->scaledScreenNext)
267     {
268         /* Only update if it has active clients... */
269         if (ptr->scaledScreenRefCount>0)
270         {
271           rfbScaledScreenUpdateRect(screen, ptr, x1, y1, x2-x1, y2-y1);
272           count++;
273         }
274     }
275 }
276 
277 /* Create a new scaled version of the framebuffer */
rfbScaledScreenAllocate(rfbClientPtr cl,int width,int height)278 rfbScreenInfoPtr rfbScaledScreenAllocate(rfbClientPtr cl, int width, int height)
279 {
280     rfbScreenInfoPtr ptr;
281     ptr = malloc(sizeof(rfbScreenInfo));
282     if (ptr!=NULL)
283     {
284         /* copy *everything* (we don't use most of it, but just in case) */
285         memcpy(ptr, cl->screen, sizeof(rfbScreenInfo));
286         ptr->width = width;
287         ptr->height = height;
288         ptr->paddedWidthInBytes = (ptr->bitsPerPixel/8)*ptr->width;
289 
290         /* Need to by multiples of 4 for Sparc systems */
291         ptr->paddedWidthInBytes += (ptr->paddedWidthInBytes % 4);
292 
293         /* Reset the reference count to 0! */
294         ptr->scaledScreenRefCount = 0;
295 
296         ptr->sizeInBytes = ptr->paddedWidthInBytes * ptr->height;
297         ptr->serverFormat = cl->screen->serverFormat;
298 
299         ptr->frameBuffer = malloc(ptr->sizeInBytes);
300         if (ptr->frameBuffer!=NULL)
301         {
302             /* Reset to a known condition: scale the entire framebuffer */
303             rfbScaledScreenUpdateRect(cl->screen, ptr, 0, 0, cl->screen->width, cl->screen->height);
304             /* Now, insert into the chain */
305             LOCK(cl->updateMutex);
306             ptr->scaledScreenNext = cl->screen->scaledScreenNext;
307             cl->screen->scaledScreenNext = ptr;
308             UNLOCK(cl->updateMutex);
309         }
310         else
311         {
312             /* Failed to malloc the new frameBuffer, cleanup */
313             free(ptr);
314             ptr=NULL;
315         }
316     }
317     return ptr;
318 }
319 
320 /* Find an active scaled version of the framebuffer
321  * TODO: implement a refcount per scaled screen to prevent
322  * unreferenced scaled screens from hanging around
323  */
rfbScalingFind(rfbClientPtr cl,int width,int height)324 rfbScreenInfoPtr rfbScalingFind(rfbClientPtr cl, int width, int height)
325 {
326     rfbScreenInfoPtr ptr;
327     /* include the original in the search (ie: fine 1:1 scaled version of the frameBuffer) */
328     for (ptr=cl->screen; ptr!=NULL; ptr=ptr->scaledScreenNext)
329     {
330         if ((ptr->width==width) && (ptr->height==height))
331             return ptr;
332     }
333     return NULL;
334 }
335 
336 /* Future needs "scale to 320x240, as that's the client's screen size */
rfbScalingSetup(rfbClientPtr cl,int width,int height)337 void rfbScalingSetup(rfbClientPtr cl, int width, int height)
338 {
339     rfbScreenInfoPtr ptr;
340 
341     ptr = rfbScalingFind(cl,width,height);
342     if (ptr==NULL)
343         ptr = rfbScaledScreenAllocate(cl,width,height);
344     /* Now, there is a new screen available (if ptr is not NULL) */
345     if (ptr!=NULL)
346     {
347         /* Update it! */
348         if (ptr->scaledScreenRefCount<1)
349             rfbScaledScreenUpdateRect(cl->screen, ptr, 0, 0, cl->screen->width, cl->screen->height);
350         /*
351          * rfbLog("Taking one from %dx%d-%d and adding it to %dx%d-%d\n",
352          *    cl->scaledScreen->width, cl->scaledScreen->height,
353          *    cl->scaledScreen->scaledScreenRefCount,
354          *    ptr->width, ptr->height, ptr->scaledScreenRefCount);
355          */
356 
357         LOCK(cl->updateMutex);
358         cl->scaledScreen->scaledScreenRefCount--;
359         ptr->scaledScreenRefCount++;
360         cl->scaledScreen=ptr;
361         cl->newFBSizePending = TRUE;
362         UNLOCK(cl->updateMutex);
363 
364         rfbLog("Scaling to %dx%d (refcount=%d)\n",width,height,ptr->scaledScreenRefCount);
365     }
366     else
367         rfbLog("Scaling to %dx%d failed, leaving things alone\n",width,height);
368 }
369 
rfbSendNewScaleSize(rfbClientPtr cl)370 int rfbSendNewScaleSize(rfbClientPtr cl)
371 {
372     /* if the client supports newFBsize Encoding, use it */
373     if (cl->useNewFBSize && cl->newFBSizePending)
374 	return FALSE;
375 
376     LOCK(cl->updateMutex);
377     cl->newFBSizePending = FALSE;
378     UNLOCK(cl->updateMutex);
379 
380     if (cl->PalmVNC==TRUE)
381     {
382         rfbPalmVNCReSizeFrameBufferMsg pmsg;
383         pmsg.type = rfbPalmVNCReSizeFrameBuffer;
384         pmsg.pad1 = 0;
385         pmsg.desktop_w = Swap16IfLE(cl->screen->width);
386         pmsg.desktop_h = Swap16IfLE(cl->screen->height);
387         pmsg.buffer_w  = Swap16IfLE(cl->scaledScreen->width);
388         pmsg.buffer_h  = Swap16IfLE(cl->scaledScreen->height);
389         pmsg.pad2 = 0;
390 
391         rfbLog("Sending a response to a PalmVNC style frameuffer resize event (%dx%d)\n", cl->scaledScreen->width, cl->scaledScreen->height);
392         if (rfbWriteExact(cl, (char *)&pmsg, sz_rfbPalmVNCReSizeFrameBufferMsg) < 0) {
393             rfbLogPerror("rfbNewClient: write");
394             rfbCloseClient(cl);
395             rfbClientConnectionGone(cl);
396             return FALSE;
397         }
398     }
399     else
400     {
401         rfbResizeFrameBufferMsg        rmsg;
402         rmsg.type = rfbResizeFrameBuffer;
403         rmsg.pad1=0;
404         rmsg.framebufferWidth  = Swap16IfLE(cl->scaledScreen->width);
405         rmsg.framebufferHeigth = Swap16IfLE(cl->scaledScreen->height);
406         rfbLog("Sending a response to a UltraVNC style frameuffer resize event (%dx%d)\n", cl->scaledScreen->width, cl->scaledScreen->height);
407         if (rfbWriteExact(cl, (char *)&rmsg, sz_rfbResizeFrameBufferMsg) < 0) {
408             rfbLogPerror("rfbNewClient: write");
409             rfbCloseClient(cl);
410             rfbClientConnectionGone(cl);
411             return FALSE;
412         }
413     }
414     return TRUE;
415 }
416 /****************************/
417