server/socket/image.C

/*
 * CrossFire, A Multiplayer game
 *
 * Copyright (C) 2005, 2006, 2007 Marc Lehmann & Crossfire+ Development Team
 * Copyright (C) 2001 Mark Wedel
 * Copyright (C) 1992 Frank Tore Johansen
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * The author can be reached via e-mail to <crossfire@schmorp.de>
 */

/** \file
 * Image related communication
 *
 *  \date 2003-12-02
 *
 * This file deals with the image related communication to the
 * client.  I've located all the functions in this file - this
 * localizes it more, and means that we don't need to declare
 * things like all the structures as globals.
 */

#include <global.h>
#include <sproto.h>

#include "crc.h"

#define MAX_FACE_SETS   20  /**< Maximum number of image sets the program will handle */

/** Information about one image */
typedef struct FaceInfo
{
  uint8 *data;              /**< image data */
  uint16 datalen;           /**< length of the xpm data */
  uint32 checksum;          /**< Checksum of face data */
} FaceInfo;

/** Information about one face set */
typedef struct
{
  char *prefix;         /**< */
  char *fullname;

  uint8 fallback;       /**< faceset to use when an image is not found in this faceset */
  char *size;
  char *extension;
  char *comment;

  FaceInfo *faces;      /**< images in this faceset */
} FaceSets;

static FaceSets facesets[MAX_FACE_SETS];    /**< All facesets */

/**
 * Checks specified faceset is valid
 * \param fsn faceset number
 */
int
is_valid_faceset (int fsn)
{
  if (fsn >= 0 && fsn < MAX_FACE_SETS && facesets[fsn].prefix)
    return TRUE;
  return FALSE;
}

/**
 * Frees all faceset information
 */
void
free_socket_images (void)
{
  int num, q;

  for (num = 0; num < MAX_FACE_SETS; num++)
    {
      if (facesets[num].prefix)
        {
          for (q = 0; q < faces.size (); q++)
            if (facesets[num].faces[q].data)
              free (facesets[num].faces[q].data);

          free (facesets[num].prefix);
          free (facesets[num].fullname);
          free (facesets[num].size);
          free (facesets[num].extension);
          free (facesets[num].comment);
          free (facesets[num].faces);
        }
    }
}

/**
 * This returns the set we will actually use when sending
 * a face.  This is used because the image files may be sparse.
 * This function is recursive.  imageno is the face number we are
 * trying to send
 *
 * If face is not found in specified faceset, tries with 'fallback' faceset.
 *
 * \param faceset faceset to check
 * \param imageno image number
 *
 */
static int
get_face_fallback (int faceset, int imageno)
{
  /* faceset 0 is supposed to have every image, so just return.  Doing
   * so also prevents infinite loops in the case if it not having
   * the face, but in that case, we are likely to crash when we try
   * to access the data, but that is probably preferable to an infinite
   * loop.
   */
  if (faceset == 0)
    return 0;

  if (!facesets[faceset].prefix)
    {
      LOG (llevError, "get_face_fallback called with unused set (%d)?\n", faceset);
      return 0;                 /* use default set */
    }

  if (facesets[faceset].faces[imageno].data)
    return faceset;

  return get_face_fallback (facesets[faceset].fallback, imageno);
}

/**
 * Checks fallback are correctly defined.
 * This is a simple recursive function that makes sure the fallbacks
 * are all proper (eg, the fall back to defined sets, and also
 * eventually fall back to 0).  At the top level, togo is set to MAX_FACE_SETS,
 * if togo gets to zero, it means we have a loop.
 * This is only run when we first load the facesets.
 */
static void
check_faceset_fallback (int faceset, int togo)
{
  int fallback = facesets[faceset].fallback;

  /* proper case - falls back to base set */
  if (fallback == 0)
    return;

  if (!facesets[fallback].prefix)
    {
      LOG (llevError, "Face set %d falls to non set faceset %d\n", faceset, fallback);
      abort ();
    }

  togo--;
  if (togo == 0)
    {
      LOG (llevError, "Infinite loop found in facesets. aborting.\n");
      abort ();
    }

  check_faceset_fallback (fallback, togo);
}

#define MAX_IMAGE_SIZE 10000

/**
 * Client tells us what type of faces it wants.  Also sets
 * the caching attribute.
 *
 */
void
SetFaceMode (char *buf, int len, client *ns)
{
  int mask = (atoi (buf) & CF_FACE_CACHE), mode = (atoi (buf) & ~CF_FACE_CACHE);

  if (mode == CF_FACE_NONE)
    ns->facecache = 1;
  else if (mode != CF_FACE_PNG)
    ns->send_packet_printf ("drawinfo %d %s", NDI_RED, "Warning - send unsupported face mode.  Will use Png");

  if (mask)
    ns->facecache = 1;
}

/**
 * Client has requested pixmap that it somehow missed getting.
 * This will be called often if the client is
 * caching images.
 */
void
SendFaceCmd (char *buf, int len, client *ns)
{
  ns->send_face (atoi (buf), 1);
}

// how lame
static void print_facename (packet &sl, const facedata &d)
{
  for (int i = 0; i < CHKSUM_SIZE; ++i)
    sl.printf ("%02x", d.chksum [i]);
}

// gcfclient uses the server-provided checksum for comparison,
// but always wrotes a broken checksum to its cache file, so we
// have to provide gcfclient with a useless checksum just to
// have to cache the image despite its bugs.
static uint32 gcfclient_checksum (const facedata *d)
{
  uint32 csum = 0;

  for (std::string::const_iterator i = d->data.begin ();
       i != d->data.end ();
       ++i)
    {
      csum = rotate_right (csum);
      csum += *(uint8 *)&*i;
    }

  return csum;
}

/**
 * Sends a face to a client if they are in pixmap mode
 * nothing gets sent in bitmap mode. 
 * If nocache is true (nonzero), ignore the cache setting from the client -
 * this is needed for the askface, in which we really do want to send the
 * face (and askface is the only place that should be setting it).  Otherwise,
 * we look at the facecache, and if set, send the image name.
 */
void
client::send_face (faceidx facenum, bool forced)
{
  // never send face 0. ever. it does not exist.
  if (!facenum)
    return;

  const facedata *d = face_data (facenum, faceset);

  if (!d)
    {
      LOG (llevError, "client::send_face (%d) out of bounds??\n", facenum);
      return;
    }

  packet sl;

  if (facecache && !forced)
    {
      if (faces_sent[facenum] & NS_FACESENT_FACE)
        return;

      faces_sent[facenum] |= NS_FACESENT_FACE;

      if (force_face0)
        sl << "face " << uint16 (facenum);
      else if (image2)
        sl << "face2 " << uint16 (facenum) << uint8 (0) << uint32 (force_bad_checksum ? gcfclient_checksum (d) : 0);
      else
        sl << "face1 " << uint16 (facenum) << uint32 (force_bad_checksum ? gcfclient_checksum (d) : 0);

      // how lame
      print_facename (sl, *d);
    }
  else
    {
      fprintf (stderr, "image %d\n", facenum);//D
      sl << (image2 ? "image2 " : "image ")
         << uint32 (facenum);

      if (image2)
        sl << uint8 (0);

      sl << uint32 (d->data.size ())
         << data (d->data.data (), d->data.size ());
    }

  send_packet (sl);
}

// send all faces of this object to the client
// this uses more bandwidth initially, but makes
// animations look much smoother, and every client
// is supposed to do client-side caching anyways.
void
client::send_faces (object *ob)
{
  send_face (ob->face);

  if (ob->animation_id)
    {
      animation &anim = animations [ob->animation_id];

      for (int i = 0; i < anim.num_animations; i++)
        send_face (anim.faces [i]);
    }
}

/**
 * A lot like the old AskSmooth (in fact, now called by AskSmooth).
 * Basically, it makes no sense to wait for the client to request a 
 * a piece of data from us that we know the client wants.  So
 * if we know the client wants it, might as well push it to the
 * client.
 */
void
client::send_smooth (faceidx face)
{
  faceinfo *f = face_info (face);

  if (!f)
    return;

  if (faces_sent[face] & NS_FACESENT_SMOOTH)
    return;

  faces_sent[face] |= NS_FACESENT_SMOOTH;

  /* If we can't find a face, return and set it so we won't try to send this
   * again.
   */
  if (!f->smooth)
    {
      LOG (llevError, "could not findsmooth for %d.\n", face);
      return;
    }

  send_face (f->smooth);

  packet sl ("smooth");

  sl << uint16 (face)
     << uint16 (f->smooth);

  send_packet (sl);
}

/**
 * Need to send an animation sequence to the client.
 * We will send appropriate face commands to the client if we haven't
 * sent them the face yet (this can become quite costly in terms of
 * how much we are sending - on the other hand, this should only happen
 * when the player logs in and picks stuff up.
 */
void
client::send_animation (short anim_num)
{
  /* Do some checking on the anim_num we got.  Note that the animations
   * are added in contigous order, so if the number is in the valid
   * range, it must be a valid animation.
   */
  if (anim_num < 0 || anim_num > num_animations)
    {
      LOG (llevError, "esrv_send_anim (%d) out of bounds??\n", anim_num);
      return;
    }

  packet sl ("anim");

  sl << uint16 (anim_num)
     << uint16 (0); /* flags - not used right now */

  /* Build up the list of faces.  Also, send any information (ie, the
   * the face itself) down to the client.
   */
  for (int i = 0; i < animations[anim_num].num_animations; i++)
    {
      send_face (animations[anim_num].faces[i]);
      sl << uint16 (animations[anim_num].faces[i]);   /* flags - not used right now */
    }

  send_packet (sl);

  anims_sent[anim_num] = 1;
}

/**
 * Sends the number of images, checksum of the face file,
 * and the image_info file information.  See the doc/Developers/protocol
 * if you want further detail.
 */
void
send_image_info (client *ns, char *params)
{
  packet sl;

  //TODO: second parameter is a checksum, but it makes no sense in this current framework
  sl.printf ("replyinfo image_info\n%d\n%u\n", MAX_FACES, 0);

  sl << "0:base:standard:0:32x32:none:The old 32x32 faceset.\n";

  ns->send_packet (sl);
}

/**
 * Sends requested face information.
 * \param ns socket to send to
 * \param params contains first and last index of face
 *
 * For each image in [start..stop] sends
 *  - checksum
 *  - name
 */
void
send_image_sums (client *ns, char *params)
{
  int start, stop;
  char *cp;

  packet sl;

  start = atoi (params);
  for (cp = params; *cp != '\0'; cp++)
    if (*cp == ' ')
      break;

  stop = atoi (cp);
  if (stop < start || *cp == '\0' || (stop - start) > 1000 || stop >= MAX_FACES)
    {
      sl.printf ("replyinfo image_sums %d %d", start, stop);
      ns->send_packet (sl);
      sl.reset ();
      return;
    }

  sl.printf ("replyinfo image_sums %d %d ", start, stop);

  for (int i = start; i <= stop && i < faces.size (); i++)
    {
      ns->faces_sent[i] |= NS_FACESENT_FACE;

      const facedata *d = face_data (i, ns->faceset);

      if (sl.room () < 2 + 4 + 1 + d->data.size () + 1)
        break;

      sl << uint16 (i)
         << uint32 (0) // checksum
         << uint8  (ns->faceset);

      print_facename (sl, *d); sl << uint8 (0);
    }

  /* It would make more sense to catch this pre-emptively in the code above.
   * however, if this really happens, we probably just want to cut down the
   * size to less than 1000, since that is what we claim the protocol would
   * support.
   */
  //TODO: taken care of above, should simply abort or make sure the above code is correct
  if (sl.length () >= MAXSOCKBUF)
    {
      LOG (llevError, "send_image_send: buffer overrun, %d > %d\n", sl.length (), MAXSOCKBUF);
      abort ();
    }

  ns->send_packet (sl);
}

Revision:	1.28
Committed:	Wed Mar 14 00:04:59 2007 UTC (17 years, 2 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.27:	+121 -23 lines
Log Message:	- rewrote smooth face handling, as a side-effect, smoothing seems to work again and smooth faces can be reloaded. - the server now sends the full animation for an object the first time it is seen, this uses slightly more bandwidth initially, but avoids the flickering for objects change their face later.
#	Content
1	/*
2	* CrossFire, A Multiplayer game
3	*
4	* Copyright (C) 2005, 2006, 2007 Marc Lehmann & Crossfire+ Development Team
5	* Copyright (C) 2001 Mark Wedel
6	* Copyright (C) 1992 Frank Tore Johansen
7	*
8	* This program is free software; you can redistribute it and/or modify
9	* it under the terms of the GNU General Public License as published by
10	* the Free Software Foundation; either version 2 of the License, or
11	* (at your option) any later version.
12	*
13	* This program is distributed in the hope that it will be useful,
14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16	* GNU General Public License for more details.
17	*
18	* You should have received a copy of the GNU General Public License
19	* along with this program; if not, write to the Free Software
20	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21	*
22	* The author can be reached via e-mail to <crossfire@schmorp.de>
23	*/
24
25	/** \file
26	* Image related communication
27	*
28	* \date 2003-12-02
29	*
30	* This file deals with the image related communication to the
31	* client. I've located all the functions in this file - this
32	* localizes it more, and means that we don't need to declare
33	* things like all the structures as globals.
34	*/
35
36	#include <global.h>
37	#include <sproto.h>
38
39	#include "crc.h"
40
41	#define MAX_FACE_SETS 20 /*< Maximum number of image sets the program will handle /
42
43	/** Information about one image */
44	typedef struct FaceInfo
45	{
46	uint8 data; /< image data /
47	uint16 datalen; /*< length of the xpm data /
48	uint32 checksum; /*< Checksum of face data /
49	} FaceInfo;
50
51	/** Information about one face set */
52	typedef struct
53	{
54	char prefix; /< /
55	char *fullname;
56
57	uint8 fallback; /*< faceset to use when an image is not found in this faceset /
58	char *size;
59	char *extension;
60	char *comment;
61
62	FaceInfo faces; /< images in this faceset /
63	} FaceSets;
64
65	static FaceSets facesets[MAX_FACE_SETS]; /*< All facesets /
66
67	/**
68	* Checks specified faceset is valid
69	* \param fsn faceset number
70	*/
71	int
72	is_valid_faceset (int fsn)
73	{
74	if (fsn >= 0 && fsn < MAX_FACE_SETS && facesets[fsn].prefix)
75	return TRUE;
76	return FALSE;
77	}
78
79	/**
80	* Frees all faceset information
81	*/
82	void
83	free_socket_images (void)
84	{
85	int num, q;
86
87	for (num = 0; num < MAX_FACE_SETS; num++)
88	{
89	if (facesets[num].prefix)
90	{
91	for (q = 0; q < faces.size (); q++)
92	if (facesets[num].faces[q].data)
93	free (facesets[num].faces[q].data);
94
95	free (facesets[num].prefix);
96	free (facesets[num].fullname);
97	free (facesets[num].size);
98	free (facesets[num].extension);
99	free (facesets[num].comment);
100	free (facesets[num].faces);
101	}
102	}
103	}
104
105	/**
106	* This returns the set we will actually use when sending
107	* a face. This is used because the image files may be sparse.
108	* This function is recursive. imageno is the face number we are
109	* trying to send
110	*
111	* If face is not found in specified faceset, tries with 'fallback' faceset.
112	*
113	* \param faceset faceset to check
114	* \param imageno image number
115	*
116	*/
117	static int
118	get_face_fallback (int faceset, int imageno)
119	{
120	/* faceset 0 is supposed to have every image, so just return. Doing
121	* so also prevents infinite loops in the case if it not having
122	* the face, but in that case, we are likely to crash when we try
123	* to access the data, but that is probably preferable to an infinite
124	* loop.
125	*/
126	if (faceset == 0)
127	return 0;
128
129	if (!facesets[faceset].prefix)
130	{
131	LOG (llevError, "get_face_fallback called with unused set (%d)?\n", faceset);
132	return 0; /* use default set */
133	}
134
135	if (facesets[faceset].faces[imageno].data)
136	return faceset;
137
138	return get_face_fallback (facesets[faceset].fallback, imageno);
139	}
140
141	/**
142	* Checks fallback are correctly defined.
143	* This is a simple recursive function that makes sure the fallbacks
144	* are all proper (eg, the fall back to defined sets, and also
145	* eventually fall back to 0). At the top level, togo is set to MAX_FACE_SETS,
146	* if togo gets to zero, it means we have a loop.
147	* This is only run when we first load the facesets.
148	*/
149	static void
150	check_faceset_fallback (int faceset, int togo)
151	{
152	int fallback = facesets[faceset].fallback;
153
154	/* proper case - falls back to base set */
155	if (fallback == 0)
156	return;
157
158	if (!facesets[fallback].prefix)
159	{
160	LOG (llevError, "Face set %d falls to non set faceset %d\n", faceset, fallback);
161	abort ();
162	}
163
164	togo--;
165	if (togo == 0)
166	{
167	LOG (llevError, "Infinite loop found in facesets. aborting.\n");
168	abort ();
169	}
170
171	check_faceset_fallback (fallback, togo);
172	}
173
174	#define MAX_IMAGE_SIZE 10000
175
176	/**
177	* Client tells us what type of faces it wants. Also sets
178	* the caching attribute.
179	*
180	*/
181	void
182	SetFaceMode (char buf, int len, client ns)
183	{
184	int mask = (atoi (buf) & CF_FACE_CACHE), mode = (atoi (buf) & ~CF_FACE_CACHE);
185
186	if (mode == CF_FACE_NONE)
187	ns->facecache = 1;
188	else if (mode != CF_FACE_PNG)
189	ns->send_packet_printf ("drawinfo %d %s", NDI_RED, "Warning - send unsupported face mode. Will use Png");
190
191	if (mask)
192	ns->facecache = 1;
193	}
194
195	/**
196	* Client has requested pixmap that it somehow missed getting.
197	* This will be called often if the client is
198	* caching images.
199	*/
200	void
201	SendFaceCmd (char buf, int len, client ns)
202	{
203	ns->send_face (atoi (buf), 1);
204	}
205
206	// how lame
207	static void print_facename (packet &sl, const facedata &d)
208	{
209	for (int i = 0; i < CHKSUM_SIZE; ++i)
210	sl.printf ("%02x", d.chksum [i]);
211	}
212
213	// gcfclient uses the server-provided checksum for comparison,
214	// but always wrotes a broken checksum to its cache file, so we
215	// have to provide gcfclient with a useless checksum just to
216	// have to cache the image despite its bugs.
217	static uint32 gcfclient_checksum (const facedata *d)
218	{
219	uint32 csum = 0;
220
221	for (std::string::const_iterator i = d->data.begin ();
222	i != d->data.end ();
223	++i)
224	{
225	csum = rotate_right (csum);
226	csum += (uint8 )&*i;
227	}
228
229	return csum;
230	}
231
232	/**
233	* Sends a face to a client if they are in pixmap mode
234	* nothing gets sent in bitmap mode.
235	* If nocache is true (nonzero), ignore the cache setting from the client -
236	* this is needed for the askface, in which we really do want to send the
237	* face (and askface is the only place that should be setting it). Otherwise,
238	* we look at the facecache, and if set, send the image name.
239	*/
240	void
241	client::send_face (faceidx facenum, bool forced)
242	{
243	// never send face 0. ever. it does not exist.
244	if (!facenum)
245	return;
246
247	const facedata *d = face_data (facenum, faceset);
248
249	if (!d)
250	{
251	LOG (llevError, "client::send_face (%d) out of bounds??\n", facenum);
252	return;
253	}
254
255	packet sl;
256
257	if (facecache && !forced)
258	{
259	if (faces_sent[facenum] & NS_FACESENT_FACE)
260	return;
261
262	faces_sent[facenum] \|= NS_FACESENT_FACE;
263
264	if (force_face0)
265	sl << "face " << uint16 (facenum);
266	else if (image2)
267	sl << "face2 " << uint16 (facenum) << uint8 (0) << uint32 (force_bad_checksum ? gcfclient_checksum (d) : 0);
268	else
269	sl << "face1 " << uint16 (facenum) << uint32 (force_bad_checksum ? gcfclient_checksum (d) : 0);
270
271	// how lame
272	print_facename (sl, *d);
273	}
274	else
275	{
276	fprintf (stderr, "image %d\n", facenum);//D
277	sl << (image2 ? "image2 " : "image ")
278	<< uint32 (facenum);
279
280	if (image2)
281	sl << uint8 (0);
282
283	sl << uint32 (d->data.size ())
284	<< data (d->data.data (), d->data.size ());
285	}
286
287	send_packet (sl);
288	}
289
290	// send all faces of this object to the client
291	// this uses more bandwidth initially, but makes
292	// animations look much smoother, and every client
293	// is supposed to do client-side caching anyways.
294	void
295	client::send_faces (object *ob)
296	{
297	send_face (ob->face);
298
299	if (ob->animation_id)
300	{
301	animation &anim = animations [ob->animation_id];
302
303	for (int i = 0; i < anim.num_animations; i++)
304	send_face (anim.faces [i]);
305	}
306	}
307
308	/**
309	* A lot like the old AskSmooth (in fact, now called by AskSmooth).
310	* Basically, it makes no sense to wait for the client to request a
311	* a piece of data from us that we know the client wants. So
312	* if we know the client wants it, might as well push it to the
313	* client.
314	*/
315	void
316	client::send_smooth (faceidx face)
317	{
318	faceinfo *f = face_info (face);
319
320	if (!f)
321	return;
322
323	if (faces_sent[face] & NS_FACESENT_SMOOTH)
324	return;
325
326	faces_sent[face] \|= NS_FACESENT_SMOOTH;
327
328	/* If we can't find a face, return and set it so we won't try to send this
329	* again.
330	*/
331	if (!f->smooth)
332	{
333	LOG (llevError, "could not findsmooth for %d.\n", face);
334	return;
335	}
336
337	send_face (f->smooth);
338
339	packet sl ("smooth");
340
341	sl << uint16 (face)
342	<< uint16 (f->smooth);
343
344	send_packet (sl);
345	}
346
347	/**
348	* Need to send an animation sequence to the client.
349	* We will send appropriate face commands to the client if we haven't
350	* sent them the face yet (this can become quite costly in terms of
351	* how much we are sending - on the other hand, this should only happen
352	* when the player logs in and picks stuff up.
353	*/
354	void
355	client::send_animation (short anim_num)
356	{
357	/* Do some checking on the anim_num we got. Note that the animations
358	* are added in contigous order, so if the number is in the valid
359	* range, it must be a valid animation.
360	*/
361	if (anim_num < 0 \|\| anim_num > num_animations)
362	{
363	LOG (llevError, "esrv_send_anim (%d) out of bounds??\n", anim_num);
364	return;
365	}
366
367	packet sl ("anim");
368
369	sl << uint16 (anim_num)
370	<< uint16 (0); /* flags - not used right now */
371
372	/* Build up the list of faces. Also, send any information (ie, the
373	* the face itself) down to the client.
374	*/
375	for (int i = 0; i < animations[anim_num].num_animations; i++)
376	{
377	send_face (animations[anim_num].faces[i]);
378	sl << uint16 (animations[anim_num].faces[i]); /* flags - not used right now */
379	}
380
381	send_packet (sl);
382
383	anims_sent[anim_num] = 1;
384	}
385
386	/**
387	* Sends the number of images, checksum of the face file,
388	* and the image_info file information. See the doc/Developers/protocol
389	* if you want further detail.
390	*/
391	void
392	send_image_info (client ns, char params)
393	{
394	packet sl;
395
396	//TODO: second parameter is a checksum, but it makes no sense in this current framework
397	sl.printf ("replyinfo image_info\n%d\n%u\n", MAX_FACES, 0);
398
399	sl << "0:base:standard:0:32x32:none:The old 32x32 faceset.\n";
400
401	ns->send_packet (sl);
402	}
403
404	/**
405	* Sends requested face information.
406	* \param ns socket to send to
407	* \param params contains first and last index of face
408	*
409	* For each image in [start..stop] sends
410	* - checksum
411	* - name
412	*/
413	void
414	send_image_sums (client ns, char params)
415	{
416	int start, stop;
417	char *cp;
418
419	packet sl;
420
421	start = atoi (params);
422	for (cp = params; *cp != '\0'; cp++)
423	if (*cp == ' ')
424	break;
425
426	stop = atoi (cp);
427	if (stop < start \|\| *cp == '\0' \|\| (stop - start) > 1000 \|\| stop >= MAX_FACES)
428	{
429	sl.printf ("replyinfo image_sums %d %d", start, stop);
430	ns->send_packet (sl);
431	sl.reset ();
432	return;
433	}
434
435	sl.printf ("replyinfo image_sums %d %d ", start, stop);
436
437	for (int i = start; i <= stop && i < faces.size (); i++)
438	{
439	ns->faces_sent[i] \|= NS_FACESENT_FACE;
440
441	const facedata *d = face_data (i, ns->faceset);
442
443	if (sl.room () < 2 + 4 + 1 + d->data.size () + 1)
444	break;
445
446	sl << uint16 (i)
447	<< uint32 (0) // checksum
448	<< uint8 (ns->faceset);
449
450	print_facename (sl, *d); sl << uint8 (0);
451	}
452
453	/* It would make more sense to catch this pre-emptively in the code above.
454	* however, if this really happens, we probably just want to cut down the
455	* size to less than 1000, since that is what we claim the protocol would
456	* support.
457	*/
458	//TODO: taken care of above, should simply abort or make sure the above code is correct
459	if (sl.length () >= MAXSOCKBUF)
460	{
461	LOG (llevError, "send_image_send: buffer overrun, %d > %d\n", sl.length (), MAXSOCKBUF);
462	abort ();
463	}
464
465	ns->send_packet (sl);
466	}
467