2 * midend.c: general middle fragment sitting between the
3 * platform-specific front end and game-specific back end.
4 * Maintains a move list, takes care of Undo and Redo commands, and
5 * processes standard keystrokes for undo/redo/new/quit.
16 enum { DEF_PARAMS, DEF_SEED, DEF_DESC }; /* for midend_game_id_int */
18 enum { NEWGAME, MOVE, SOLVE, RESTART };/* for midend_state_entry.movetype */
20 #define special(type) ( (type) != MOVE )
22 struct midend_state_entry {
33 game_params **presets;
35 int npresets, presetsize;
38 * `desc' and `privdesc' deserve a comment.
40 * `desc' is the game description as presented to the user when
41 * they ask for Game -> Specific. `privdesc', if non-NULL, is a
42 * different game description used to reconstruct the initial
43 * game_state when de-serialising. If privdesc is NULL, `desc'
46 * For almost all games, `privdesc' is NULL and never used. The
47 * exception (as usual) is Mines: the initial game state has no
48 * squares open at all, but after the first click `desc' is
49 * rewritten to describe a game state with an initial click and
50 * thus a bunch of squares open. If we used that desc to
51 * serialise and deserialise, then the initial game state after
52 * deserialisation would look unlike the initial game state
53 * beforehand, and worse still execute_move() might fail on the
54 * attempted first click. So `privdesc' is also used in this
55 * case, to provide a game description describing the same
56 * fixed mine layout _but_ no initial click. (These game IDs
57 * may also be typed directly into Mines if you like.)
59 char *desc, *privdesc, *seedstr;
61 enum { GOT_SEED, GOT_DESC, GOT_NOTHING } genmode;
63 int nstates, statesize, statepos;
64 struct midend_state_entry *states;
66 game_params *params, *curparams;
67 game_drawstate *drawstate;
71 float anim_time, anim_pos;
72 float flash_time, flash_pos;
79 int pressed_mouse_button;
81 int winwidth, winheight;
84 #define ensure(me) do { \
85 if ((me)->nstates >= (me)->statesize) { \
86 (me)->statesize = (me)->nstates + 128; \
87 (me)->states = sresize((me)->states, (me)->statesize, \
88 struct midend_state_entry); \
92 midend_data *midend_new(frontend *fe, const game *ourgame)
94 midend_data *me = snew(midend_data);
98 get_random_seed(&randseed, &randseedsize);
101 me->ourgame = ourgame;
102 me->random = random_init(randseed, randseedsize);
103 me->nstates = me->statesize = me->statepos = 0;
105 me->params = ourgame->default_params();
106 me->curparams = NULL;
107 me->desc = me->privdesc = NULL;
110 me->genmode = GOT_NOTHING;
111 me->drawstate = NULL;
114 me->preset_names = NULL;
115 me->npresets = me->presetsize = 0;
116 me->anim_time = me->anim_pos = 0.0F;
117 me->flash_time = me->flash_pos = 0.0F;
120 me->pressed_mouse_button = 0;
121 me->laststatus = NULL;
124 me->winwidth = me->winheight = 0;
131 static void midend_free_game(midend_data *me)
133 while (me->nstates > 0) {
135 me->ourgame->free_game(me->states[me->nstates].state);
136 sfree(me->states[me->nstates].movestr);
140 me->ourgame->free_drawstate(me->drawstate);
143 void midend_free(midend_data *me)
147 midend_free_game(me);
149 random_free(me->random);
155 me->ourgame->free_params(me->params);
157 for (i = 0; i < me->npresets; i++) {
158 sfree(me->presets[i]);
159 sfree(me->preset_names[i]);
162 sfree(me->preset_names);
165 me->ourgame->free_ui(me->ui);
167 me->ourgame->free_params(me->curparams);
168 sfree(me->laststatus);
172 void midend_size(midend_data *me, int *x, int *y, int expand)
174 me->ourgame->size(me->params, me->drawstate, x, y, expand);
179 void midend_set_params(midend_data *me, game_params *params)
181 me->ourgame->free_params(me->params);
182 me->params = me->ourgame->dup_params(params);
185 static void midend_set_timer(midend_data *me)
187 me->timing = (me->ourgame->is_timed &&
188 me->ourgame->timing_state(me->states[me->statepos-1].state));
189 if (me->timing || me->flash_time || me->anim_time)
190 activate_timer(me->frontend);
192 deactivate_timer(me->frontend);
195 static void midend_size_new_drawstate(midend_data *me)
197 me->ourgame->size(me->params, me->drawstate, &me->winwidth, &me->winheight,
201 void midend_force_redraw(midend_data *me)
204 me->ourgame->free_drawstate(me->drawstate);
205 me->drawstate = me->ourgame->new_drawstate(me->states[0].state);
206 midend_size_new_drawstate(me);
210 void midend_new_game(midend_data *me)
212 midend_free_game(me);
214 assert(me->nstates == 0);
216 if (me->genmode == GOT_DESC) {
217 me->genmode = GOT_NOTHING;
221 if (me->genmode == GOT_SEED) {
222 me->genmode = GOT_NOTHING;
225 * Generate a new random seed. 15 digits comes to about
226 * 48 bits, which should be more than enough.
228 * I'll avoid putting a leading zero on the number,
229 * just in case it confuses anybody who thinks it's
230 * processed as an integer rather than a string.
235 newseed[0] = '1' + random_upto(me->random, 9);
236 for (i = 1; i < 15; i++)
237 newseed[i] = '0' + random_upto(me->random, 10);
239 me->seedstr = dupstr(newseed);
242 me->ourgame->free_params(me->curparams);
243 me->curparams = me->ourgame->dup_params(me->params);
251 rs = random_init(me->seedstr, strlen(me->seedstr));
252 me->desc = me->ourgame->new_desc(me->curparams, rs,
253 &me->aux_info, TRUE);
259 me->states[me->nstates].state =
260 me->ourgame->new_game(me, me->params, me->desc);
261 me->states[me->nstates].movestr = NULL;
262 me->states[me->nstates].movetype = NEWGAME;
265 me->drawstate = me->ourgame->new_drawstate(me->states[0].state);
266 midend_size_new_drawstate(me);
268 midend_set_timer(me);
270 me->ourgame->free_ui(me->ui);
271 me->ui = me->ourgame->new_ui(me->states[0].state);
272 me->pressed_mouse_button = 0;
275 static int midend_undo(midend_data *me)
277 if (me->statepos > 1) {
279 me->ourgame->changed_state(me->ui,
280 me->states[me->statepos-1].state,
281 me->states[me->statepos-2].state);
289 static int midend_redo(midend_data *me)
291 if (me->statepos < me->nstates) {
293 me->ourgame->changed_state(me->ui,
294 me->states[me->statepos-1].state,
295 me->states[me->statepos].state);
303 static void midend_finish_move(midend_data *me)
308 * We do not flash if the later of the two states is special.
309 * This covers both forward Solve moves and backward (undone)
312 if ((me->oldstate || me->statepos > 1) &&
313 ((me->dir > 0 && !special(me->states[me->statepos-1].movetype)) ||
314 (me->dir < 0 && me->statepos < me->nstates &&
315 !special(me->states[me->statepos].movetype)))) {
316 flashtime = me->ourgame->flash_length(me->oldstate ? me->oldstate :
317 me->states[me->statepos-2].state,
318 me->states[me->statepos-1].state,
319 me->oldstate ? me->dir : +1,
322 me->flash_pos = 0.0F;
323 me->flash_time = flashtime;
328 me->ourgame->free_game(me->oldstate);
330 me->anim_pos = me->anim_time = 0;
333 midend_set_timer(me);
336 void midend_stop_anim(midend_data *me)
338 if (me->oldstate || me->anim_time) {
339 midend_finish_move(me);
344 void midend_restart_game(midend_data *me)
348 midend_stop_anim(me);
350 assert(me->statepos >= 1);
351 if (me->statepos == 1)
352 return; /* no point doing anything at all! */
355 * During restart, we reconstruct the game from the (public)
356 * game description rather than from states[0], because that
357 * way Mines gets slightly more sensible behaviour (restart
358 * goes to _after_ the first click so you don't have to
359 * remember where you clicked).
361 s = me->ourgame->new_game(me, me->params, me->desc);
364 * Now enter the restarted state as the next move.
366 midend_stop_anim(me);
367 while (me->nstates > me->statepos)
368 me->ourgame->free_game(me->states[--me->nstates].state);
370 me->states[me->nstates].state = s;
371 me->states[me->nstates].movestr = dupstr(me->desc);
372 me->states[me->nstates].movetype = RESTART;
373 me->statepos = ++me->nstates;
375 me->ourgame->changed_state(me->ui,
376 me->states[me->statepos-2].state,
377 me->states[me->statepos-1].state);
379 midend_finish_move(me);
381 midend_set_timer(me);
384 static int midend_really_process_key(midend_data *me, int x, int y, int button)
386 game_state *oldstate =
387 me->ourgame->dup_game(me->states[me->statepos - 1].state);
388 int special = FALSE, gotspecial = FALSE, ret = 1;
391 if (button == 'n' || button == 'N' || button == '\x0E') {
392 midend_stop_anim(me);
395 goto done; /* never animate */
396 } else if (button == 'u' || button == 'u' ||
397 button == '\x1A' || button == '\x1F') {
398 midend_stop_anim(me);
399 special = special(me->states[me->statepos-1].movetype);
401 if (!midend_undo(me))
403 } else if (button == 'r' || button == 'R' ||
404 button == '\x12' || button == '\x19') {
405 midend_stop_anim(me);
406 if (!midend_redo(me))
408 } else if (button == 'q' || button == 'Q' || button == '\x11') {
416 me->ourgame->interpret_move(me->states[me->statepos-1].state,
417 me->ui, me->drawstate, x, y, button);
421 s = me->states[me->statepos-1].state;
423 s = me->ourgame->execute_move(me->states[me->statepos-1].state,
428 if (s == me->states[me->statepos-1].state) {
430 * make_move() is allowed to return its input state to
431 * indicate that although no move has been made, the UI
432 * state has been updated and a redraw is called for.
437 midend_stop_anim(me);
438 while (me->nstates > me->statepos)
439 me->ourgame->free_game(me->states[--me->nstates].state);
441 assert(movestr != NULL);
442 me->states[me->nstates].state = s;
443 me->states[me->nstates].movestr = movestr;
444 me->states[me->nstates].movetype = MOVE;
445 me->statepos = ++me->nstates;
453 special = special(me->states[me->statepos-1].movetype);
456 * See if this move requires an animation.
461 anim_time = me->ourgame->anim_length(oldstate,
462 me->states[me->statepos-1].state,
466 me->oldstate = oldstate; oldstate = NULL;
468 me->anim_time = anim_time;
471 midend_finish_move(me);
477 midend_set_timer(me);
480 if (oldstate) me->ourgame->free_game(oldstate);
484 int midend_process_key(midend_data *me, int x, int y, int button)
489 * Harmonise mouse drag and release messages.
491 * Some front ends might accidentally switch from sending, say,
492 * RIGHT_DRAG messages to sending LEFT_DRAG, half way through a
493 * drag. (This can happen on the Mac, for example, since
494 * RIGHT_DRAG is usually done using Command+drag, and if the
495 * user accidentally releases Command half way through the drag
496 * then there will be trouble.)
498 * It would be an O(number of front ends) annoyance to fix this
499 * in the front ends, but an O(number of back ends) annoyance
500 * to have each game capable of dealing with it. Therefore, we
501 * fix it _here_ in the common midend code so that it only has
504 * The possible ways in which things can go screwy in the front
507 * - in a system containing multiple physical buttons button
508 * presses can inadvertently overlap. We can see ABab (caps
509 * meaning button-down and lowercase meaning button-up) when
510 * the user had semantically intended AaBb.
512 * - in a system where one button is simulated by means of a
513 * modifier key and another button, buttons can mutate
514 * between press and release (possibly during drag). So we
515 * can see Ab instead of Aa.
517 * Definite requirements are:
519 * - button _presses_ must never be invented or destroyed. If
520 * the user presses two buttons in succession, the button
521 * presses must be transferred to the backend unchanged. So
522 * if we see AaBb , that's fine; if we see ABab (the button
523 * presses inadvertently overlapped) we must somehow
524 * `correct' it to AaBb.
526 * - every mouse action must end up looking like a press, zero
527 * or more drags, then a release. This allows back ends to
528 * make the _assumption_ that incoming mouse data will be
529 * sane in this regard, and not worry about the details.
531 * So my policy will be:
533 * - treat any button-up as a button-up for the currently
534 * pressed button, or ignore it if there is no currently
537 * - treat any drag as a drag for the currently pressed
538 * button, or ignore it if there is no currently pressed
541 * - if we see a button-down while another button is currently
542 * pressed, invent a button-up for the first one and then
543 * pass the button-down through as before.
545 * 2005-05-31: An addendum to the above. Some games might want
546 * a `priority order' among buttons, such that if one button is
547 * pressed while another is down then a fixed one of the
548 * buttons takes priority no matter what order they're pressed
549 * in. Mines, in particular, wants to treat a left+right click
550 * like a left click for the benefit of users of other
551 * implementations. So the last of the above points is modified
552 * in the presence of an (optional) button priority order.
554 if (IS_MOUSE_DRAG(button) || IS_MOUSE_RELEASE(button)) {
555 if (me->pressed_mouse_button) {
556 if (IS_MOUSE_DRAG(button)) {
557 button = me->pressed_mouse_button +
558 (LEFT_DRAG - LEFT_BUTTON);
560 button = me->pressed_mouse_button +
561 (LEFT_RELEASE - LEFT_BUTTON);
564 return ret; /* ignore it */
565 } else if (IS_MOUSE_DOWN(button) && me->pressed_mouse_button) {
567 * If the new button has lower priority than the old one,
568 * don't bother doing this.
570 if (me->ourgame->mouse_priorities &
571 BUTTON_BEATS(me->pressed_mouse_button, button))
572 return ret; /* just ignore it */
575 * Fabricate a button-up for the previously pressed button.
577 ret = ret && midend_really_process_key
578 (me, x, y, (me->pressed_mouse_button +
579 (LEFT_RELEASE - LEFT_BUTTON)));
583 * Now send on the event we originally received.
585 ret = ret && midend_really_process_key(me, x, y, button);
588 * And update the currently pressed button.
590 if (IS_MOUSE_RELEASE(button))
591 me->pressed_mouse_button = 0;
592 else if (IS_MOUSE_DOWN(button))
593 me->pressed_mouse_button = button;
598 void midend_redraw(midend_data *me)
600 if (me->statepos > 0 && me->drawstate) {
601 start_draw(me->frontend);
602 if (me->oldstate && me->anim_time > 0 &&
603 me->anim_pos < me->anim_time) {
604 assert(me->dir != 0);
605 me->ourgame->redraw(me->frontend, me->drawstate, me->oldstate,
606 me->states[me->statepos-1].state, me->dir,
607 me->ui, me->anim_pos, me->flash_pos);
609 me->ourgame->redraw(me->frontend, me->drawstate, NULL,
610 me->states[me->statepos-1].state, +1 /*shrug*/,
611 me->ui, 0.0, me->flash_pos);
613 end_draw(me->frontend);
617 void midend_timer(midend_data *me, float tplus)
619 me->anim_pos += tplus;
620 if (me->anim_pos >= me->anim_time ||
621 me->anim_time == 0 || !me->oldstate) {
622 if (me->anim_time > 0)
623 midend_finish_move(me);
626 me->flash_pos += tplus;
627 if (me->flash_pos >= me->flash_time || me->flash_time == 0) {
628 me->flash_pos = me->flash_time = 0;
634 float oldelapsed = me->elapsed;
635 me->elapsed += tplus;
636 if ((int)oldelapsed != (int)me->elapsed)
637 status_bar(me->frontend, me->laststatus ? me->laststatus : "");
640 midend_set_timer(me);
643 float *midend_colours(midend_data *me, int *ncolours)
645 game_state *state = NULL;
648 if (me->nstates == 0) {
650 char *desc = me->ourgame->new_desc(me->params, me->random,
652 state = me->ourgame->new_game(me, me->params, desc);
656 state = me->states[0].state;
658 ret = me->ourgame->colours(me->frontend, state, ncolours);
664 * Allow environment-based overrides for the standard
665 * colours by defining variables along the lines of
666 * `NET_COLOUR_4=6000c0'.
669 for (i = 0; i < *ncolours; i++) {
671 unsigned int r, g, b;
674 sprintf(buf, "%s_COLOUR_%d", me->ourgame->name, i);
675 for (j = 0; buf[j]; j++)
676 buf[j] = toupper((unsigned char)buf[j]);
677 if ((e = getenv(buf)) != NULL &&
678 sscanf(e, "%2x%2x%2x", &r, &g, &b) == 3) {
679 ret[i*3 + 0] = r / 255.0;
680 ret[i*3 + 1] = g / 255.0;
681 ret[i*3 + 2] = b / 255.0;
686 if (me->nstates == 0)
687 me->ourgame->free_game(state);
692 int midend_num_presets(midend_data *me)
698 while (me->ourgame->fetch_preset(me->npresets, &name, &preset)) {
699 if (me->presetsize <= me->npresets) {
700 me->presetsize = me->npresets + 10;
701 me->presets = sresize(me->presets, me->presetsize,
703 me->preset_names = sresize(me->preset_names, me->presetsize,
707 me->presets[me->npresets] = preset;
708 me->preset_names[me->npresets] = name;
715 * Allow environment-based extensions to the preset list by
716 * defining a variable along the lines of `SOLO_PRESETS=2x3
717 * Advanced:2x3da'. Colon-separated list of items,
718 * alternating between textual titles in the menu and
719 * encoded parameter strings.
721 char buf[80], *e, *p;
724 sprintf(buf, "%s_PRESETS", me->ourgame->name);
725 for (j = 0; buf[j]; j++)
726 buf[j] = toupper((unsigned char)buf[j]);
728 if ((e = getenv(buf)) != NULL) {
736 while (*p && *p != ':') p++;
739 while (*p && *p != ':') p++;
742 preset = me->ourgame->default_params();
743 me->ourgame->decode_params(preset, val);
745 if (me->ourgame->validate_params(preset)) {
746 /* Drop this one from the list. */
747 me->ourgame->free_params(preset);
751 if (me->presetsize <= me->npresets) {
752 me->presetsize = me->npresets + 10;
753 me->presets = sresize(me->presets, me->presetsize,
755 me->preset_names = sresize(me->preset_names,
756 me->presetsize, char *);
759 me->presets[me->npresets] = preset;
760 me->preset_names[me->npresets] = name;
769 void midend_fetch_preset(midend_data *me, int n,
770 char **name, game_params **params)
772 assert(n >= 0 && n < me->npresets);
773 *name = me->preset_names[n];
774 *params = me->presets[n];
777 int midend_wants_statusbar(midend_data *me)
779 return me->ourgame->wants_statusbar();
782 void midend_supersede_game_desc(midend_data *me, char *desc, char *privdesc)
786 me->desc = dupstr(desc);
787 me->privdesc = privdesc ? dupstr(privdesc) : NULL;
790 config_item *midend_get_config(midend_data *me, int which, char **wintitle)
792 char *titlebuf, *parstr, *rest;
797 titlebuf = snewn(40 + strlen(me->ourgame->name), char);
801 sprintf(titlebuf, "%s configuration", me->ourgame->name);
802 *wintitle = titlebuf;
803 return me->ourgame->configure(me->params);
806 if (!me->curparams) {
810 sprintf(titlebuf, "%s %s selection", me->ourgame->name,
811 which == CFG_SEED ? "random" : "game");
812 *wintitle = titlebuf;
814 ret = snewn(2, config_item);
816 ret[0].type = C_STRING;
817 if (which == CFG_SEED)
818 ret[0].name = "Game random seed";
820 ret[0].name = "Game ID";
823 * For CFG_DESC the text going in here will be a string
824 * encoding of the restricted parameters, plus a colon,
825 * plus the game description. For CFG_SEED it will be the
826 * full parameters, plus a hash, plus the random seed data.
827 * Either of these is a valid full game ID (although only
828 * the former is likely to persist across many code
831 parstr = me->ourgame->encode_params(me->curparams, which == CFG_SEED);
833 if (which == CFG_DESC) {
834 rest = me->desc ? me->desc : "";
837 rest = me->seedstr ? me->seedstr : "";
840 ret[0].sval = snewn(strlen(parstr) + strlen(rest) + 2, char);
841 sprintf(ret[0].sval, "%s%c%s", parstr, sep, rest);
845 ret[1].name = ret[1].sval = NULL;
851 assert(!"We shouldn't be here");
855 static char *midend_game_id_int(midend_data *me, char *id, int defmode)
857 char *error, *par, *desc, *seed;
859 seed = strchr(id, '#');
860 desc = strchr(id, ':');
862 if (desc && (!seed || desc < seed)) {
864 * We have a colon separating parameters from game
865 * description. So `par' now points to the parameters
866 * string, and `desc' to the description string.
871 } else if (seed && (!desc || seed < desc)) {
873 * We have a hash separating parameters from random seed.
874 * So `par' now points to the parameters string, and `seed'
875 * to the seed string.
882 * We only have one string. Depending on `defmode', we take
883 * it to be either parameters, seed or description.
885 if (defmode == DEF_SEED) {
888 } else if (defmode == DEF_DESC) {
898 game_params *tmpparams;
899 tmpparams = me->ourgame->dup_params(me->params);
900 me->ourgame->decode_params(tmpparams, par);
901 error = me->ourgame->validate_params(tmpparams);
903 me->ourgame->free_params(tmpparams);
907 me->ourgame->free_params(me->curparams);
908 me->curparams = tmpparams;
911 * Now filter only the persistent parts of this state into
912 * the long-term params structure, unless we've _only_
913 * received a params string in which case the whole lot is
917 char *tmpstr = me->ourgame->encode_params(tmpparams, FALSE);
918 me->ourgame->decode_params(me->params, tmpstr);
921 me->ourgame->free_params(me->params);
922 me->params = me->ourgame->dup_params(tmpparams);
928 me->desc = me->privdesc = NULL;
933 error = me->ourgame->validate_desc(me->params, desc);
937 me->desc = dupstr(desc);
938 me->genmode = GOT_DESC;
944 me->seedstr = dupstr(seed);
945 me->genmode = GOT_SEED;
951 char *midend_game_id(midend_data *me, char *id)
953 return midend_game_id_int(me, id, DEF_PARAMS);
956 char *midend_set_config(midend_data *me, int which, config_item *cfg)
963 params = me->ourgame->custom_params(cfg);
964 error = me->ourgame->validate_params(params);
967 me->ourgame->free_params(params);
971 me->ourgame->free_params(me->params);
977 error = midend_game_id_int(me, cfg[0].sval,
978 (which == CFG_SEED ? DEF_SEED : DEF_DESC));
987 char *midend_text_format(midend_data *me)
989 if (me->ourgame->can_format_as_text && me->statepos > 0)
990 return me->ourgame->text_format(me->states[me->statepos-1].state);
995 char *midend_solve(midend_data *me)
1000 if (!me->ourgame->can_solve)
1001 return "This game does not support the Solve operation";
1003 if (me->statepos < 1)
1004 return "No game set up to solve"; /* _shouldn't_ happen! */
1006 msg = "Solve operation failed"; /* game _should_ overwrite on error */
1007 movestr = me->ourgame->solve(me->states[0].state,
1008 me->states[me->statepos-1].state,
1009 me->aux_info, &msg);
1012 s = me->ourgame->execute_move(me->states[me->statepos-1].state, movestr);
1016 * Now enter the solved state as the next move.
1018 midend_stop_anim(me);
1019 while (me->nstates > me->statepos)
1020 me->ourgame->free_game(me->states[--me->nstates].state);
1022 me->states[me->nstates].state = s;
1023 me->states[me->nstates].movestr = movestr;
1024 me->states[me->nstates].movetype = SOLVE;
1025 me->statepos = ++me->nstates;
1027 me->ourgame->changed_state(me->ui,
1028 me->states[me->statepos-2].state,
1029 me->states[me->statepos-1].state);
1030 me->anim_time = 0.0;
1031 midend_finish_move(me);
1033 midend_set_timer(me);
1037 char *midend_rewrite_statusbar(midend_data *me, char *text)
1040 * An important special case is that we are occasionally called
1041 * with our own laststatus, to update the timer.
1043 if (me->laststatus != text) {
1044 sfree(me->laststatus);
1045 me->laststatus = dupstr(text);
1048 if (me->ourgame->is_timed) {
1049 char timebuf[100], *ret;
1055 sprintf(timebuf, "[%d:%02d] ", min, sec);
1057 ret = snewn(strlen(timebuf) + strlen(text) + 1, char);
1058 strcpy(ret, timebuf);
1063 return dupstr(text);
1067 #define SERIALISE_MAGIC "Simon Tatham's Portable Puzzle Collection"
1068 #define SERIALISE_VERSION "1"
1070 void midend_serialise(midend_data *me,
1071 void (*write)(void *ctx, void *buf, int len),
1077 * Each line of the save file contains three components. First
1078 * exactly 8 characters of header word indicating what type of
1079 * data is contained on the line; then a colon followed by a
1080 * decimal integer giving the length of the main string on the
1081 * line; then a colon followed by the string itself (exactly as
1082 * many bytes as previously specified, no matter what they
1083 * contain). Then a newline (of reasonably flexible form).
1085 #define wr(h,s) do { \
1088 sprintf(hbuf, "%-8.8s:%d:", (h), (int)strlen(str)); \
1089 write(wctx, hbuf, strlen(hbuf)); \
1090 write(wctx, str, strlen(str)); \
1091 write(wctx, "\n", 1); \
1095 * Magic string identifying the file, and version number of the
1098 wr("SAVEFILE", SERIALISE_MAGIC);
1099 wr("VERSION", SERIALISE_VERSION);
1102 * The game name. (Copied locally to avoid const annoyance.)
1105 char *s = dupstr(me->ourgame->name);
1111 * The current long-term parameters structure, in full.
1114 char *s = me->ourgame->encode_params(me->params, TRUE);
1120 * The current short-term parameters structure, in full.
1122 if (me->curparams) {
1123 char *s = me->ourgame->encode_params(me->curparams, TRUE);
1129 * The current game description, the privdesc, and the random seed.
1132 wr("SEED", me->seedstr);
1134 wr("DESC", me->desc);
1136 wr("PRIVDESC", me->privdesc);
1139 * The game's aux_info. We obfuscate this to prevent spoilers
1140 * (people are likely to run `head' or similar on a saved game
1141 * file simply to find out what it is, and don't necessarily
1142 * want to be told the answer to the puzzle!)
1149 len = strlen(me->aux_info);
1150 s1 = snewn(len, unsigned char);
1151 memcpy(s1, me->aux_info, len);
1152 obfuscate_bitmap(s1, len*8, FALSE);
1153 s2 = bin2hex(s1, len);
1162 * Any required serialisation of the game_ui.
1165 char *s = me->ourgame->encode_ui(me->ui);
1173 * The game time, if it's a timed game.
1175 if (me->ourgame->is_timed) {
1177 sprintf(buf, "%g", me->elapsed);
1182 * The length of, and position in, the states list.
1186 sprintf(buf, "%d", me->nstates);
1188 sprintf(buf, "%d", me->statepos);
1189 wr("STATEPOS", buf);
1193 * For each state after the initial one (which we know is
1194 * constructed from either privdesc or desc), enough
1195 * information for execute_move() to reconstruct it from the
1198 for (i = 1; i < me->nstates; i++) {
1199 assert(me->states[i].movetype != NEWGAME); /* only state 0 */
1200 switch (me->states[i].movetype) {
1202 wr("MOVE", me->states[i].movestr);
1205 wr("SOLVE", me->states[i].movestr);
1208 wr("RESTART", me->states[i].movestr);
1217 * This function returns NULL on success, or an error message.
1219 char *midend_deserialise(midend_data *me,
1220 int (*read)(void *ctx, void *buf, int len),
1223 int nstates = 0, statepos = -1, gotstates = 0;
1224 int started = FALSE;
1228 /* Initially all errors give the same report */
1229 char *ret = "Data does not appear to be a saved game file";
1232 * We construct all the new state in local variables while we
1233 * check its sanity. Only once we have finished reading the
1234 * serialised data and detected no errors at all do we start
1235 * modifying stuff in the midend_data passed in.
1237 char *seed = NULL, *parstr = NULL, *desc = NULL, *privdesc = NULL;
1238 char *auxinfo = NULL, *uistr = NULL, *cparstr = NULL;
1239 float elapsed = 0.0F;
1240 game_params *params = NULL, *cparams = NULL;
1242 struct midend_state_entry *states = NULL;
1245 * Loop round and round reading one key/value pair at a time
1246 * from the serialised stream, until we have enough game states
1249 while (nstates <= 0 || statepos < 0 || gotstates < nstates-1) {
1254 if (!read(rctx, key, 1)) {
1255 /* unexpected EOF */
1258 } while (key[0] == '\r' || key[0] == '\n');
1260 if (!read(rctx, key+1, 8)) {
1261 /* unexpected EOF */
1265 if (key[8] != ':') {
1267 ret = "Data was incorrectly formatted for a saved game file";
1269 len = strcspn(key, ": ");
1275 if (!read(rctx, &c, 1)) {
1276 /* unexpected EOF */
1282 } else if (c >= '0' && c <= '9') {
1283 len = (len * 10) + (c - '0');
1286 ret = "Data was incorrectly formatted for a"
1292 val = snewn(len+1, char);
1293 if (!read(rctx, val, len)) {
1300 if (strcmp(key, "SAVEFILE") || strcmp(val, SERIALISE_MAGIC)) {
1301 /* ret already has the right message in it */
1304 /* Now most errors are this one, unless otherwise specified */
1305 ret = "Saved data ended unexpectedly";
1308 if (!strcmp(key, "VERSION")) {
1309 if (strcmp(val, SERIALISE_VERSION)) {
1310 ret = "Cannot handle this version of the saved game"
1314 } else if (!strcmp(key, "GAME")) {
1315 if (strcmp(val, me->ourgame->name)) {
1316 ret = "Save file is from a different game";
1319 } else if (!strcmp(key, "PARAMS")) {
1323 } else if (!strcmp(key, "CPARAMS")) {
1327 } else if (!strcmp(key, "SEED")) {
1331 } else if (!strcmp(key, "DESC")) {
1335 } else if (!strcmp(key, "PRIVDESC")) {
1339 } else if (!strcmp(key, "AUXINFO")) {
1341 int len = strlen(val) / 2; /* length in bytes */
1342 tmp = hex2bin(val, len);
1343 obfuscate_bitmap(tmp, len*8, TRUE);
1346 auxinfo = snewn(len + 1, char);
1347 memcpy(auxinfo, tmp, len);
1348 auxinfo[len] = '\0';
1350 } else if (!strcmp(key, "UI")) {
1354 } else if (!strcmp(key, "TIME")) {
1355 elapsed = atof(val);
1356 } else if (!strcmp(key, "NSTATES")) {
1357 nstates = atoi(val);
1359 ret = "Number of states in save file was negative";
1363 ret = "Two state counts provided in save file";
1366 states = snewn(nstates, struct midend_state_entry);
1367 for (i = 0; i < nstates; i++) {
1368 states[i].state = NULL;
1369 states[i].movestr = NULL;
1370 states[i].movetype = NEWGAME;
1372 } else if (!strcmp(key, "STATEPOS")) {
1373 statepos = atoi(val);
1374 } else if (!strcmp(key, "MOVE")) {
1376 states[gotstates].movetype = MOVE;
1377 states[gotstates].movestr = val;
1379 } else if (!strcmp(key, "SOLVE")) {
1381 states[gotstates].movetype = SOLVE;
1382 states[gotstates].movestr = val;
1384 } else if (!strcmp(key, "RESTART")) {
1386 states[gotstates].movetype = RESTART;
1387 states[gotstates].movestr = val;
1396 params = me->ourgame->default_params();
1397 me->ourgame->decode_params(params, parstr);
1398 if (me->ourgame->validate_params(params)) {
1399 ret = "Long-term parameters in save file are invalid";
1402 cparams = me->ourgame->default_params();
1403 me->ourgame->decode_params(cparams, cparstr);
1404 if (me->ourgame->validate_params(cparams)) {
1405 ret = "Short-term parameters in save file are invalid";
1409 ret = "Game description in save file is missing";
1411 } else if (me->ourgame->validate_desc(params, desc)) {
1412 ret = "Game description in save file is invalid";
1415 if (privdesc && me->ourgame->validate_desc(params, privdesc)) {
1416 ret = "Game private description in save file is invalid";
1419 if (statepos < 0 || statepos >= nstates) {
1420 ret = "Game position in save file is out of range";
1423 states[0].state = me->ourgame->new_game(me, params,
1424 privdesc ? privdesc : desc);
1425 for (i = 1; i < nstates; i++) {
1426 assert(states[i].movetype != NEWGAME);
1427 switch (states[i].movetype) {
1430 states[i].state = me->ourgame->execute_move(states[i-1].state,
1432 if (states[i].state == NULL) {
1433 ret = "Save file contained an invalid move";
1438 if (me->ourgame->validate_desc(params, states[i].movestr)) {
1439 ret = "Save file contained an invalid restart move";
1442 states[i].state = me->ourgame->new_game(me, params,
1448 ui = me->ourgame->new_ui(states[0].state);
1449 me->ourgame->decode_ui(ui, uistr);
1452 * Now we've run out of possible error conditions, so we're
1453 * ready to start overwriting the real data in the current
1454 * midend. We'll do this by swapping things with the local
1455 * variables, so that the same cleanup code will free the old
1466 me->privdesc = privdesc;
1474 me->aux_info = auxinfo;
1478 me->genmode = GOT_NOTHING;
1480 me->statesize = nstates;
1481 nstates = me->nstates;
1482 me->nstates = me->statesize;
1484 struct midend_state_entry *tmp;
1486 me->states = states;
1489 me->statepos = statepos;
1495 me->params = params;
1498 tmp = me->curparams;
1499 me->curparams = cparams;
1503 me->oldstate = NULL;
1504 me->anim_time = me->anim_pos = me->flash_time = me->flash_pos = 0.0F;
1515 me->elapsed = elapsed;
1516 me->pressed_mouse_button = 0;
1518 midend_set_timer(me);
1521 me->ourgame->free_drawstate(me->drawstate);
1523 me->ourgame->new_drawstate(me->states[me->statepos-1].state);
1524 midend_size_new_drawstate(me);
1526 ret = NULL; /* success! */
1538 me->ourgame->free_params(params);
1540 me->ourgame->free_params(cparams);
1542 me->ourgame->free_ui(ui);
1546 for (i = 0; i < nstates; i++) {
1547 if (states[i].state)
1548 me->ourgame->free_game(states[i].state);
1549 sfree(states[i].movestr);