ref: 4ec2c580453b0629b9935cb1e90017de6d110608
dir: /midend.c/
/*
* midend.c: general middle fragment sitting between the
* platform-specific front end and game-specific back end.
* Maintains a move list, takes care of Undo and Redo commands, and
* processes standard keystrokes for undo/redo/new/quit.
*/
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <stdlib.h>
#include <ctype.h>
#include "puzzles.h"
enum { DEF_PARAMS, DEF_SEED, DEF_DESC }; /* for midend_game_id_int */
enum { NEWGAME, MOVE, SOLVE, RESTART };/* for midend_state_entry.movetype */
#define special(type) ( (type) != MOVE )
struct midend_state_entry {
game_state *state;
char *movestr;
int movetype;
};
struct midend_serialise_buf {
char *buf;
int len, size;
};
struct midend {
frontend *frontend;
random_state *random;
const game *ourgame;
struct preset_menu *preset_menu;
char **encoded_presets; /* for midend_which_preset to check against */
int n_encoded_presets;
/*
* `desc' and `privdesc' deserve a comment.
*
* `desc' is the game description as presented to the user when
* they ask for Game -> Specific. `privdesc', if non-NULL, is a
* different game description used to reconstruct the initial
* game_state when de-serialising. If privdesc is NULL, `desc'
* is used for both.
*
* For almost all games, `privdesc' is NULL and never used. The
* exception (as usual) is Mines: the initial game state has no
* squares open at all, but after the first click `desc' is
* rewritten to describe a game state with an initial click and
* thus a bunch of squares open. If we used that desc to
* serialise and deserialise, then the initial game state after
* deserialisation would look unlike the initial game state
* beforehand, and worse still execute_move() might fail on the
* attempted first click. So `privdesc' is also used in this
* case, to provide a game description describing the same
* fixed mine layout _but_ no initial click. (These game IDs
* may also be typed directly into Mines if you like.)
*/
char *desc, *privdesc, *seedstr;
char *aux_info;
enum { GOT_SEED, GOT_DESC, GOT_NOTHING } genmode;
int nstates, statesize, statepos;
struct midend_state_entry *states;
struct midend_serialise_buf newgame_undo, newgame_redo;
bool newgame_can_store_undo;
game_params *params, *curparams;
game_drawstate *drawstate;
bool first_draw;
game_ui *ui;
game_state *oldstate;
float anim_time, anim_pos;
float flash_time, flash_pos;
int dir;
bool timing;
float elapsed;
char *laststatus;
drawing *drawing;
int pressed_mouse_button;
int preferred_tilesize, preferred_tilesize_dpr, tilesize;
int winwidth, winheight;
void (*game_id_change_notify_function)(void *);
void *game_id_change_notify_ctx;
};
#define ensure(me) do { \
if ((me)->nstates >= (me)->statesize) { \
(me)->statesize = (me)->nstates + 128; \
(me)->states = sresize((me)->states, (me)->statesize, \
struct midend_state_entry); \
} \
} while (0)
/*
* Structure storing all the decoded data from reading a serialised
* game. We keep it in one of these while we check its sanity, and
* only once we're completely satisfied do we install it all in the
* midend structure proper.
*/
struct deserialise_data {
char *seed, *parstr, *desc, *privdesc;
char *auxinfo, *uistr, *cparstr;
float elapsed;
game_params *params, *cparams;
game_ui *ui;
struct midend_state_entry *states;
int nstates, statepos;
};
/*
* Forward reference.
*/
static const char *midend_deserialise_internal(
midend *me, bool (*read)(void *ctx, void *buf, int len), void *rctx,
const char *(*check)(void *ctx, midend *, const struct deserialise_data *),
void *cctx);
void midend_reset_tilesize(midend *me)
{
me->preferred_tilesize = me->ourgame->preferred_tilesize;
me->preferred_tilesize_dpr = 1.0;
{
/*
* Allow an environment-based override for the default tile
* size by defining a variable along the lines of
* `NET_TILESIZE=15'.
*
* XXX How should this interact with DPR?
*/
char buf[80], *e;
int j, k, ts;
sprintf(buf, "%s_TILESIZE", me->ourgame->name);
for (j = k = 0; buf[j]; j++)
if (!isspace((unsigned char)buf[j]))
buf[k++] = toupper((unsigned char)buf[j]);
buf[k] = '\0';
if ((e = getenv(buf)) != NULL && sscanf(e, "%d", &ts) == 1 && ts > 0)
me->preferred_tilesize = ts;
}
}
midend *midend_new(frontend *fe, const game *ourgame,
const drawing_api *drapi, void *drhandle)
{
midend *me = snew(midend);
void *randseed;
int randseedsize;
get_random_seed(&randseed, &randseedsize);
me->frontend = fe;
me->ourgame = ourgame;
me->random = random_new(randseed, randseedsize);
me->nstates = me->statesize = me->statepos = 0;
me->states = NULL;
me->newgame_undo.buf = NULL;
me->newgame_undo.size = me->newgame_undo.len = 0;
me->newgame_redo.buf = NULL;
me->newgame_redo.size = me->newgame_redo.len = 0;
me->newgame_can_store_undo = false;
me->params = ourgame->default_params();
me->game_id_change_notify_function = NULL;
me->game_id_change_notify_ctx = NULL;
me->encoded_presets = NULL;
me->n_encoded_presets = 0;
/*
* Allow environment-based changing of the default settings by
* defining a variable along the lines of `NET_DEFAULT=25x25w'
* in which the value is an encoded parameter string.
*/
{
char buf[80], *e;
int j, k;
sprintf(buf, "%s_DEFAULT", me->ourgame->name);
for (j = k = 0; buf[j]; j++)
if (!isspace((unsigned char)buf[j]))
buf[k++] = toupper((unsigned char)buf[j]);
buf[k] = '\0';
if ((e = getenv(buf)) != NULL)
me->ourgame->decode_params(me->params, e);
}
me->curparams = NULL;
me->desc = me->privdesc = NULL;
me->seedstr = NULL;
me->aux_info = NULL;
me->genmode = GOT_NOTHING;
me->drawstate = NULL;
me->first_draw = true;
me->oldstate = NULL;
me->preset_menu = NULL;
me->anim_time = me->anim_pos = 0.0F;
me->flash_time = me->flash_pos = 0.0F;
me->dir = 0;
me->ui = NULL;
me->pressed_mouse_button = 0;
me->laststatus = NULL;
me->timing = false;
me->elapsed = 0.0F;
me->tilesize = me->winwidth = me->winheight = 0;
if (drapi)
me->drawing = drawing_new(drapi, me, drhandle);
else
me->drawing = NULL;
midend_reset_tilesize(me);
sfree(randseed);
return me;
}
const game *midend_which_game(midend *me)
{
return me->ourgame;
}
static void midend_purge_states(midend *me)
{
while (me->nstates > me->statepos) {
me->ourgame->free_game(me->states[--me->nstates].state);
if (me->states[me->nstates].movestr)
sfree(me->states[me->nstates].movestr);
}
me->newgame_redo.len = 0;
}
static void midend_free_game(midend *me)
{
while (me->nstates > 0) {
me->nstates--;
me->ourgame->free_game(me->states[me->nstates].state);
sfree(me->states[me->nstates].movestr);
}
if (me->drawstate)
me->ourgame->free_drawstate(me->drawing, me->drawstate);
}
static void midend_free_preset_menu(midend *me, struct preset_menu *menu)
{
if (menu) {
int i;
for (i = 0; i < menu->n_entries; i++) {
sfree(menu->entries[i].title);
if (menu->entries[i].params)
me->ourgame->free_params(menu->entries[i].params);
midend_free_preset_menu(me, menu->entries[i].submenu);
}
sfree(menu->entries);
sfree(menu);
}
}
void midend_free(midend *me)
{
int i;
midend_free_game(me);
for (i = 0; i < me->n_encoded_presets; i++)
sfree(me->encoded_presets[i]);
sfree(me->encoded_presets);
if (me->drawing)
drawing_free(me->drawing);
random_free(me->random);
sfree(me->newgame_undo.buf);
sfree(me->newgame_redo.buf);
sfree(me->states);
sfree(me->desc);
sfree(me->privdesc);
sfree(me->seedstr);
sfree(me->aux_info);
me->ourgame->free_params(me->params);
midend_free_preset_menu(me, me->preset_menu);
if (me->ui)
me->ourgame->free_ui(me->ui);
if (me->curparams)
me->ourgame->free_params(me->curparams);
sfree(me->laststatus);
sfree(me);
}
static void midend_size_new_drawstate(midend *me)
{
/*
* Don't even bother, if we haven't worked out our tile size
* anyway yet.
*/
if (me->tilesize > 0) {
me->ourgame->compute_size(me->params, me->tilesize,
&me->winwidth, &me->winheight);
me->ourgame->set_size(me->drawing, me->drawstate,
me->params, me->tilesize);
}
}
/*
* There is no one correct way to convert tilesizes between device
* pixel ratios, because there's only a loosely-defined relationship
* between tilesize and the actual size of a puzzle. We define this
* function as the canonical conversion function so everything in the
* midend will be consistent.
*/
static int convert_tilesize(midend *me, int old_tilesize,
double old_dpr, double new_dpr)
{
int x, y, rx, ry, min, max;
game_params *defaults = me->ourgame->default_params();
if (new_dpr == old_dpr)
return old_tilesize;
me->ourgame->compute_size(defaults, old_tilesize, &x, &y);
x *= new_dpr / old_dpr;
y *= new_dpr / old_dpr;
min = max = 1;
do {
max *= 2;
me->ourgame->compute_size(defaults, max, &rx, &ry);
} while (rx <= x && ry <= y);
while (max - min > 1) {
int mid = (max + min) / 2;
me->ourgame->compute_size(defaults, mid, &rx, &ry);
if (rx <= x && ry <= y)
min = mid;
else
max = mid;
}
me->ourgame->free_params(defaults);
return min;
}
void midend_size(midend *me, int *x, int *y, bool user_size,
double device_pixel_ratio)
{
int min, max;
int rx, ry;
/*
* We can't set the size on the same drawstate twice. So if
* we've already sized one drawstate, we must throw it away and
* create a new one.
*/
if (me->drawstate && me->tilesize > 0) {
me->ourgame->free_drawstate(me->drawing, me->drawstate);
me->drawstate = me->ourgame->new_drawstate(me->drawing,
me->states[0].state);
me->first_draw = true;
}
/*
* Find the tile size that best fits within the given space. If
* `user_size' is true, we must actually find the _largest_ such
* tile size, in order to get as close to the user's explicit
* request as possible; otherwise, we bound above at the game's
* preferred tile size, so that the game gets what it wants
* provided that this doesn't break the constraint from the
* front-end (which is likely to be a screen size or similar).
*/
if (user_size) {
max = 1;
do {
max *= 2;
me->ourgame->compute_size(me->params, max, &rx, &ry);
} while (rx <= *x && ry <= *y);
} else
max = convert_tilesize(me, me->preferred_tilesize,
me->preferred_tilesize_dpr,
device_pixel_ratio) + 1;
min = 1;
/*
* Now binary-search between min and max. We're looking for a
* boundary rather than a value: the point at which tile sizes
* stop fitting within the given dimensions. Thus, we stop when
* max and min differ by exactly 1.
*/
while (max - min > 1) {
int mid = (max + min) / 2;
me->ourgame->compute_size(me->params, mid, &rx, &ry);
if (rx <= *x && ry <= *y)
min = mid;
else
max = mid;
}
/*
* Now `min' is a valid size, and `max' isn't. So use `min'.
*/
me->tilesize = min;
if (user_size) {
/* If the user requested a change in size, make it permanent. */
me->preferred_tilesize = me->tilesize;
me->preferred_tilesize_dpr = device_pixel_ratio;
}
midend_size_new_drawstate(me);
*x = me->winwidth;
*y = me->winheight;
}
int midend_tilesize(midend *me) { return me->tilesize; }
void midend_set_params(midend *me, game_params *params)
{
me->ourgame->free_params(me->params);
me->params = me->ourgame->dup_params(params);
}
game_params *midend_get_params(midend *me)
{
return me->ourgame->dup_params(me->params);
}
static char *encode_params(midend *me, const game_params *params, bool full)
{
char *encoded = me->ourgame->encode_params(params, full);
int i;
/* Assert that the params consist of printable ASCII containing
* neither '#' nor ':'. */
for (i = 0; encoded[i]; i++)
assert(encoded[i] >= 32 && encoded[i] < 127 &&
encoded[i] != '#' && encoded[i] != ':');
return encoded;
}
static void assert_printable_ascii(char const *s)
{
/* Assert that s is entirely printable ASCII, and hence safe for
* writing in a save file. */
int i;
for (i = 0; s[i]; i++)
assert(s[i] >= 32 && s[i] < 127);
}
static void midend_set_timer(midend *me)
{
me->timing = (me->ourgame->is_timed &&
me->ourgame->timing_state(me->states[me->statepos-1].state,
me->ui));
if (me->timing || me->flash_time || me->anim_time)
activate_timer(me->frontend);
else
deactivate_timer(me->frontend);
}
void midend_force_redraw(midend *me)
{
if (me->drawstate)
me->ourgame->free_drawstate(me->drawing, me->drawstate);
me->drawstate = me->ourgame->new_drawstate(me->drawing,
me->states[0].state);
me->first_draw = true;
midend_size_new_drawstate(me);
midend_redraw(me);
}
static void newgame_serialise_write(void *ctx, const void *buf, int len)
{
struct midend_serialise_buf *ser = (struct midend_serialise_buf *)ctx;
int new_len;
assert(len < INT_MAX - ser->len);
new_len = ser->len + len;
if (new_len > ser->size) {
ser->size = new_len + new_len / 4 + 1024;
ser->buf = sresize(ser->buf, ser->size, char);
}
memcpy(ser->buf + ser->len, buf, len);
ser->len = new_len;
}
void midend_new_game(midend *me)
{
me->newgame_undo.len = 0;
if (me->newgame_can_store_undo) {
/*
* Serialise the whole of the game that we're about to
* supersede, so that the 'New Game' action can be undone
* later.
*
* We omit this in various situations, such as if there
* _isn't_ a current game (not even a starting position)
* because this is the initial call to midend_new_game when
* the midend is first set up, or if the midend state has
* already begun to be overwritten by midend_set_config. In
* those situations, we want to avoid writing out any
* serialisation, because they will be either invalid, or
* worse, valid but wrong.
*/
midend_purge_states(me);
midend_serialise(me, newgame_serialise_write, &me->newgame_undo);
}
midend_stop_anim(me);
midend_free_game(me);
assert(me->nstates == 0);
if (me->genmode == GOT_DESC) {
me->genmode = GOT_NOTHING;
} else {
random_state *rs;
if (me->genmode == GOT_SEED) {
me->genmode = GOT_NOTHING;
} else {
/*
* Generate a new random seed. 15 digits comes to about
* 48 bits, which should be more than enough.
*
* I'll avoid putting a leading zero on the number,
* just in case it confuses anybody who thinks it's
* processed as an integer rather than a string.
*/
char newseed[16];
int i;
newseed[15] = '\0';
newseed[0] = '1' + (char)random_upto(me->random, 9);
for (i = 1; i < 15; i++)
newseed[i] = '0' + (char)random_upto(me->random, 10);
sfree(me->seedstr);
me->seedstr = dupstr(newseed);
if (me->curparams)
me->ourgame->free_params(me->curparams);
me->curparams = me->ourgame->dup_params(me->params);
}
sfree(me->desc);
sfree(me->privdesc);
sfree(me->aux_info);
me->aux_info = NULL;
rs = random_new(me->seedstr, strlen(me->seedstr));
/*
* If this midend has been instantiated without providing a
* drawing API, it is non-interactive. This means that it's
* being used for bulk game generation, and hence we should
* pass the non-interactive flag to new_desc.
*/
me->desc = me->ourgame->new_desc(me->curparams, rs,
&me->aux_info, (me->drawing != NULL));
assert_printable_ascii(me->desc);
me->privdesc = NULL;
random_free(rs);
}
ensure(me);
/*
* It might seem a bit odd that we're using me->params to
* create the initial game state, rather than me->curparams
* which is better tailored to this specific game and which we
* always know.
*
* It's supposed to be an invariant in the midend that
* me->params and me->curparams differ in no aspect that is
* important after generation (i.e. after new_desc()). By
* deliberately passing the _less_ specific of these two
* parameter sets, we provoke play-time misbehaviour in the
* case where a game has failed to encode a play-time parameter
* in the non-full version of encode_params().
*/
me->states[me->nstates].state =
me->ourgame->new_game(me, me->params, me->desc);
/*
* As part of our commitment to self-testing, test the aux
* string to make sure nothing ghastly went wrong.
*/
if (me->ourgame->can_solve && me->aux_info) {
game_state *s;
const char *msg;
char *movestr;
msg = NULL;
movestr = me->ourgame->solve(me->states[0].state,
me->states[0].state,
me->aux_info, &msg);
assert(movestr && !msg);
s = me->ourgame->execute_move(me->states[0].state, movestr);
assert(s);
me->ourgame->free_game(s);
sfree(movestr);
}
me->states[me->nstates].movestr = NULL;
me->states[me->nstates].movetype = NEWGAME;
me->nstates++;
me->statepos = 1;
me->drawstate = me->ourgame->new_drawstate(me->drawing,
me->states[0].state);
me->first_draw = true;
midend_size_new_drawstate(me);
me->elapsed = 0.0F;
me->flash_pos = me->flash_time = 0.0F;
me->anim_pos = me->anim_time = 0.0F;
if (me->ui)
me->ourgame->free_ui(me->ui);
me->ui = me->ourgame->new_ui(me->states[0].state);
midend_set_timer(me);
me->pressed_mouse_button = 0;
if (me->game_id_change_notify_function)
me->game_id_change_notify_function(me->game_id_change_notify_ctx);
me->newgame_can_store_undo = true;
}
bool midend_can_undo(midend *me)
{
return (me->statepos > 1 || me->newgame_undo.len);
}
bool midend_can_redo(midend *me)
{
return (me->statepos < me->nstates || me->newgame_redo.len);
}
struct newgame_undo_deserialise_read_ctx {
struct midend_serialise_buf *ser;
int len, pos;
};
static bool newgame_undo_deserialise_read(void *ctx, void *buf, int len)
{
struct newgame_undo_deserialise_read_ctx *const rctx = ctx;
if (len > rctx->len - rctx->pos)
return false;
memcpy(buf, rctx->ser->buf + rctx->pos, len);
rctx->pos += len;
return true;
}
struct newgame_undo_deserialise_check_ctx {
bool refused;
};
static const char *newgame_undo_deserialise_check(
void *vctx, midend *me, const struct deserialise_data *data)
{
struct newgame_undo_deserialise_check_ctx *ctx =
(struct newgame_undo_deserialise_check_ctx *)vctx;
char *old, *new;
/*
* Undoing a New Game operation is only permitted if it doesn't
* change the game parameters. The point of having the ability at
* all is to recover from the momentary finger error of having hit
* the 'n' key (perhaps in place of some other nearby key), or hit
* the New Game menu item by mistake when aiming for the adjacent
* Restart; in both those situations, the game params are the same
* before and after the new-game operation.
*
* In principle, we could generalise this so that _any_ call to
* midend_new_game could be undone, but that would need all front
* ends to be alert to the possibility that any keystroke passed
* to midend_process_key might (if it turns out to have been one
* of the synonyms for undo, which the frontend doesn't
* necessarily check for) have various knock-on effects like
* needing to select a different preset in the game type menu, or
* even resizing the window. At least for the moment, it's easier
* not to do that, and to simply disallow any newgame-undo that is
* disruptive in either of those ways.
*
* We check both params and cparams, to be as safe as possible.
*/
old = encode_params(me, me->params, true);
new = encode_params(me, data->params, true);
if (strcmp(old, new)) {
/* Set a flag to distinguish this deserialise failure
* from one due to faulty decoding */
ctx->refused = true;
return "Undoing this new-game operation would change params";
}
old = encode_params(me, me->curparams, true);
new = encode_params(me, data->cparams, true);
if (strcmp(old, new)) {
ctx->refused = true;
return "Undoing this new-game operation would change params";
}
/*
* Otherwise, fine, go ahead.
*/
return NULL;
}
static bool midend_undo(midend *me)
{
const char *deserialise_error;
if (me->statepos > 1) {
if (me->ui)
me->ourgame->changed_state(me->ui,
me->states[me->statepos-1].state,
me->states[me->statepos-2].state);
me->statepos--;
me->dir = -1;
return true;
} else if (me->newgame_undo.len) {
struct newgame_undo_deserialise_read_ctx rctx;
struct newgame_undo_deserialise_check_ctx cctx;
struct midend_serialise_buf serbuf;
/*
* Serialise the current game so that you can later redo past
* this undo. Once we're committed to the undo actually
* happening, we'll copy this data into place.
*/
serbuf.buf = NULL;
serbuf.len = serbuf.size = 0;
midend_serialise(me, newgame_serialise_write, &serbuf);
rctx.ser = &me->newgame_undo;
rctx.len = me->newgame_undo.len; /* copy for reentrancy safety */
rctx.pos = 0;
cctx.refused = false;
deserialise_error = midend_deserialise_internal(
me, newgame_undo_deserialise_read, &rctx,
newgame_undo_deserialise_check, &cctx);
if (cctx.refused) {
/*
* Our post-deserialisation check shows that we can't use
* this saved game after all. (deserialise_error will
* contain the dummy error message generated by our check
* function, which we ignore.)
*/
sfree(serbuf.buf);
return false;
} else {
/*
* There should never be any _other_ deserialisation
* error, because this serialised data has been held in
* our memory since it was created, and hasn't had any
* opportunity to be corrupted on disk, accidentally
* replaced by the wrong file, etc., by user error.
*/
assert(!deserialise_error);
/*
* Clear the old newgame_undo serialisation, so that we
* don't try to undo past the beginning of the game we've
* just gone back to and end up at the front of it again.
*/
me->newgame_undo.len = 0;
/*
* Copy the serialisation of the game we've just left into
* the midend so that we can redo back into it later.
*/
me->newgame_redo.len = 0;
newgame_serialise_write(&me->newgame_redo, serbuf.buf, serbuf.len);
sfree(serbuf.buf);
return true;
}
} else
return false;
}
static bool midend_redo(midend *me)
{
const char *deserialise_error;
if (me->statepos < me->nstates) {
if (me->ui)
me->ourgame->changed_state(me->ui,
me->states[me->statepos-1].state,
me->states[me->statepos].state);
me->statepos++;
me->dir = +1;
return true;
} else if (me->newgame_redo.len) {
struct newgame_undo_deserialise_read_ctx rctx;
struct newgame_undo_deserialise_check_ctx cctx;
struct midend_serialise_buf serbuf;
/*
* Serialise the current game so that you can later undo past
* this redo. Once we're committed to the undo actually
* happening, we'll copy this data into place.
*/
serbuf.buf = NULL;
serbuf.len = serbuf.size = 0;
midend_serialise(me, newgame_serialise_write, &serbuf);
rctx.ser = &me->newgame_redo;
rctx.len = me->newgame_redo.len; /* copy for reentrancy safety */
rctx.pos = 0;
cctx.refused = false;
deserialise_error = midend_deserialise_internal(
me, newgame_undo_deserialise_read, &rctx,
newgame_undo_deserialise_check, &cctx);
if (cctx.refused) {
/*
* Our post-deserialisation check shows that we can't use
* this saved game after all. (deserialise_error will
* contain the dummy error message generated by our check
* function, which we ignore.)
*/
sfree(serbuf.buf);
return false;
} else {
/*
* There should never be any _other_ deserialisation
* error, because this serialised data has been held in
* our memory since it was created, and hasn't had any
* opportunity to be corrupted on disk, accidentally
* replaced by the wrong file, etc., by user error.
*/
assert(!deserialise_error);
/*
* Clear the old newgame_redo serialisation, so that we
* don't try to redo past the end of the game we've just
* come into and end up at the back of it again.
*/
me->newgame_redo.len = 0;
/*
* Copy the serialisation of the game we've just left into
* the midend so that we can undo back into it later.
*/
me->newgame_undo.len = 0;
newgame_serialise_write(&me->newgame_undo, serbuf.buf, serbuf.len);
sfree(serbuf.buf);
return true;
}
} else
return false;
}
static void midend_finish_move(midend *me)
{
float flashtime;
/*
* We do not flash if the later of the two states is special.
* This covers both forward Solve moves and backward (undone)
* Restart moves.
*/
if ((me->oldstate || me->statepos > 1) &&
((me->dir > 0 && !special(me->states[me->statepos-1].movetype)) ||
(me->dir < 0 && me->statepos < me->nstates &&
!special(me->states[me->statepos].movetype)))) {
flashtime = me->ourgame->flash_length(me->oldstate ? me->oldstate :
me->states[me->statepos-2].state,
me->states[me->statepos-1].state,
me->oldstate ? me->dir : +1,
me->ui);
if (flashtime > 0) {
me->flash_pos = 0.0F;
me->flash_time = flashtime;
}
}
if (me->oldstate)
me->ourgame->free_game(me->oldstate);
me->oldstate = NULL;
me->anim_pos = me->anim_time = 0;
me->dir = 0;
midend_set_timer(me);
}
void midend_stop_anim(midend *me)
{
if (me->oldstate || me->anim_time != 0) {
midend_finish_move(me);
midend_redraw(me);
}
}
void midend_restart_game(midend *me)
{
game_state *s;
assert(me->statepos >= 1);
if (me->statepos == 1)
return; /* no point doing anything at all! */
/*
* During restart, we reconstruct the game from the (public)
* game description rather than from states[0], because that
* way Mines gets slightly more sensible behaviour (restart
* goes to _after_ the first click so you don't have to
* remember where you clicked).
*/
s = me->ourgame->new_game(me, me->params, me->desc);
/*
* Now enter the restarted state as the next move.
*/
midend_stop_anim(me);
midend_purge_states(me);
ensure(me);
me->states[me->nstates].state = s;
me->states[me->nstates].movestr = dupstr(me->desc);
me->states[me->nstates].movetype = RESTART;
me->statepos = ++me->nstates;
if (me->ui)
me->ourgame->changed_state(me->ui,
me->states[me->statepos-2].state,
me->states[me->statepos-1].state);
me->flash_pos = me->flash_time = 0.0F;
midend_finish_move(me);
midend_redraw(me);
midend_set_timer(me);
}
static bool midend_really_process_key(midend *me, int x, int y, int button,
bool *handled)
{
game_state *oldstate =
me->ourgame->dup_game(me->states[me->statepos - 1].state);
int type = MOVE;
bool gottype = false, ret = true;
float anim_time;
game_state *s;
char *movestr = NULL;
if (!IS_UI_FAKE_KEY(button)) {
movestr = me->ourgame->interpret_move(
me->states[me->statepos-1].state,
me->ui, me->drawstate, x, y, button);
}
if (!movestr) {
if (button == 'n' || button == 'N' || button == '\x0E' ||
button == UI_NEWGAME) {
midend_new_game(me);
midend_redraw(me);
*handled = true;
goto done; /* never animate */
} else if (button == 'u' || button == 'U' || button == '*' ||
button == '\x1A' || button == '\x1F' ||
button == UI_UNDO) {
midend_stop_anim(me);
type = me->states[me->statepos-1].movetype;
gottype = true;
if (!midend_undo(me))
goto done;
*handled = true;
} else if (button == 'r' || button == 'R' || button == '#' ||
button == '\x12' || button == '\x19' ||
button == UI_REDO) {
midend_stop_anim(me);
if (!midend_redo(me))
goto done;
*handled = true;
} else if ((button == '\x13' || button == UI_SOLVE) &&
me->ourgame->can_solve) {
*handled = true;
if (midend_solve(me))
goto done;
} else if (button == 'q' || button == 'Q' || button == '\x11' ||
button == UI_QUIT) {
ret = false;
*handled = true;
goto done;
} else
goto done;
} else {
*handled = true;
if (movestr == UI_UPDATE)
s = me->states[me->statepos-1].state;
else {
assert_printable_ascii(movestr);
s = me->ourgame->execute_move(me->states[me->statepos-1].state,
movestr);
assert(s != NULL);
}
if (s == me->states[me->statepos-1].state) {
/*
* make_move() is allowed to return its input state to
* indicate that although no move has been made, the UI
* state has been updated and a redraw is called for.
*/
midend_redraw(me);
midend_set_timer(me);
goto done;
} else if (s) {
midend_stop_anim(me);
midend_purge_states(me);
ensure(me);
assert(movestr != NULL);
me->states[me->nstates].state = s;
me->states[me->nstates].movestr = movestr;
me->states[me->nstates].movetype = MOVE;
me->statepos = ++me->nstates;
me->dir = +1;
if (me->ui)
me->ourgame->changed_state(me->ui,
me->states[me->statepos-2].state,
me->states[me->statepos-1].state);
} else {
goto done;
}
}
if (!gottype)
type = me->states[me->statepos-1].movetype;
/*
* See if this move requires an animation.
*/
if (special(type) && !(type == SOLVE &&
(me->ourgame->flags & SOLVE_ANIMATES))) {
anim_time = 0;
} else {
anim_time = me->ourgame->anim_length(oldstate,
me->states[me->statepos-1].state,
me->dir, me->ui);
}
me->oldstate = oldstate; oldstate = NULL;
if (anim_time > 0) {
me->anim_time = anim_time;
} else {
me->anim_time = 0.0;
midend_finish_move(me);
}
me->anim_pos = 0.0;
midend_redraw(me);
midend_set_timer(me);
done:
if (oldstate) me->ourgame->free_game(oldstate);
return ret;
}
bool midend_process_key(midend *me, int x, int y, int button, bool *handled)
{
bool ret = true, dummy_handled;
if (handled == NULL) handled = &dummy_handled;
*handled = false;
/*
* Harmonise mouse drag and release messages.
*
* Some front ends might accidentally switch from sending, say,
* RIGHT_DRAG messages to sending LEFT_DRAG, half way through a
* drag. (This can happen on the Mac, for example, since
* RIGHT_DRAG is usually done using Command+drag, and if the
* user accidentally releases Command half way through the drag
* then there will be trouble.)
*
* It would be an O(number of front ends) annoyance to fix this
* in the front ends, but an O(number of back ends) annoyance
* to have each game capable of dealing with it. Therefore, we
* fix it _here_ in the common midend code so that it only has
* to be done once.
*
* The possible ways in which things can go screwy in the front
* end are:
*
* - in a system containing multiple physical buttons button
* presses can inadvertently overlap. We can see ABab (caps
* meaning button-down and lowercase meaning button-up) when
* the user had semantically intended AaBb.
*
* - in a system where one button is simulated by means of a
* modifier key and another button, buttons can mutate
* between press and release (possibly during drag). So we
* can see Ab instead of Aa.
*
* Definite requirements are:
*
* - button _presses_ must never be invented or destroyed. If
* the user presses two buttons in succession, the button
* presses must be transferred to the backend unchanged. So
* if we see AaBb , that's fine; if we see ABab (the button
* presses inadvertently overlapped) we must somehow
* `correct' it to AaBb.
*
* - every mouse action must end up looking like a press, zero
* or more drags, then a release. This allows back ends to
* make the _assumption_ that incoming mouse data will be
* sane in this regard, and not worry about the details.
*
* So my policy will be:
*
* - treat any button-up as a button-up for the currently
* pressed button, or ignore it if there is no currently
* pressed button.
*
* - treat any drag as a drag for the currently pressed
* button, or ignore it if there is no currently pressed
* button.
*
* - if we see a button-down while another button is currently
* pressed, invent a button-up for the first one and then
* pass the button-down through as before.
*
* 2005-05-31: An addendum to the above. Some games might want
* a `priority order' among buttons, such that if one button is
* pressed while another is down then a fixed one of the
* buttons takes priority no matter what order they're pressed
* in. Mines, in particular, wants to treat a left+right click
* like a left click for the benefit of users of other
* implementations. So the last of the above points is modified
* in the presence of an (optional) button priority order.
*
* A further addition: we translate certain keyboard presses to
* cursor key 'select' buttons, so that a) frontends don't have
* to translate these themselves (like they do for CURSOR_UP etc),
* and b) individual games don't have to hard-code button presses
* of '\n' etc for keyboard-based cursors. The choice of buttons
* here could eventually be controlled by a runtime configuration
* option.
*/
if (IS_MOUSE_DRAG(button) || IS_MOUSE_RELEASE(button)) {
if (me->pressed_mouse_button) {
if (IS_MOUSE_DRAG(button)) {
button = me->pressed_mouse_button +
(LEFT_DRAG - LEFT_BUTTON);
} else {
button = me->pressed_mouse_button +
(LEFT_RELEASE - LEFT_BUTTON);
}
} else
return ret; /* ignore it */
} else if (IS_MOUSE_DOWN(button) && me->pressed_mouse_button) {
/*
* If the new button has lower priority than the old one,
* don't bother doing this.
*/
if (me->ourgame->flags &
BUTTON_BEATS(me->pressed_mouse_button, button))
return ret; /* just ignore it */
/*
* Fabricate a button-up for the previously pressed button.
*/
ret = ret && midend_really_process_key
(me, x, y, (me->pressed_mouse_button +
(LEFT_RELEASE - LEFT_BUTTON)), handled);
}
/*
* Translate keyboard presses to cursor selection.
*/
if (button == '\n' || button == '\r')
button = CURSOR_SELECT;
if (button == ' ')
button = CURSOR_SELECT2;
/*
* Normalise both backspace characters (8 and 127) to \b. Easier
* to do this once, here, than to require all front ends to
* carefully generate the same one - now each front end can
* generate whichever is easiest.
*/
if (button == '\177')
button = '\b';
/*
* Now send on the event we originally received.
*/
ret = ret && midend_really_process_key(me, x, y, button, handled);
/*
* And update the currently pressed button.
*/
if (IS_MOUSE_RELEASE(button))
me->pressed_mouse_button = 0;
else if (IS_MOUSE_DOWN(button))
me->pressed_mouse_button = button;
return ret;
}
key_label *midend_request_keys(midend *me, int *n)
{
key_label *keys = NULL;
int nkeys = 0, i;
if(me->ourgame->request_keys)
{
keys = me->ourgame->request_keys(midend_get_params(me), &nkeys);
for(i = 0; i < nkeys; ++i)
{
if(!keys[i].label)
keys[i].label = button2label(keys[i].button);
}
}
if(n)
*n = nkeys;
return keys;
}
/* Return a good label to show next to a key right now. */
const char *midend_current_key_label(midend *me, int button)
{
assert(IS_CURSOR_SELECT(button));
if (!me->ourgame->current_key_label) return "";
return me->ourgame->current_key_label(
me->ui, me->states[me->statepos-1].state, button);
}
void midend_redraw(midend *me)
{
assert(me->drawing);
if (me->statepos > 0 && me->drawstate) {
bool first_draw = me->first_draw;
me->first_draw = false;
start_draw(me->drawing);
if (first_draw) {
/*
* The initial contents of the window are not guaranteed
* by the front end. But we also don't want to require
* every single game to go to the effort of clearing the
* window on setup. So we centralise here the operation of
* covering the whole window with colour 0 (assumed to be
* the puzzle's background colour) the first time we do a
* redraw operation with a new drawstate.
*/
draw_rect(me->drawing, 0, 0, me->winwidth, me->winheight, 0);
}
if (me->oldstate && me->anim_time > 0 &&
me->anim_pos < me->anim_time) {
assert(me->dir != 0);
me->ourgame->redraw(me->drawing, me->drawstate, me->oldstate,
me->states[me->statepos-1].state, me->dir,
me->ui, me->anim_pos, me->flash_pos);
} else {
me->ourgame->redraw(me->drawing, me->drawstate, NULL,
me->states[me->statepos-1].state, +1 /*shrug*/,
me->ui, 0.0, me->flash_pos);
}
if (first_draw) {
/*
* Call a big draw_update on the whole window, in case the
* game backend didn't.
*/
draw_update(me->drawing, 0, 0, me->winwidth, me->winheight);
}
end_draw(me->drawing);
}
}
/*
* Nasty hacky function used to implement the --redo option in
* gtk.c. Only used for generating the puzzles' icons.
*/
void midend_freeze_timer(midend *me, float tprop)
{
me->anim_pos = me->anim_time * tprop;
midend_redraw(me);
deactivate_timer(me->frontend);
}
void midend_timer(midend *me, float tplus)
{
bool need_redraw = (me->anim_time > 0 || me->flash_time > 0);
me->anim_pos += tplus;
if (me->anim_pos >= me->anim_time ||
me->anim_time == 0 || !me->oldstate) {
if (me->anim_time > 0)
midend_finish_move(me);
}
me->flash_pos += tplus;
if (me->flash_pos >= me->flash_time || me->flash_time == 0) {
me->flash_pos = me->flash_time = 0;
}
if (need_redraw)
midend_redraw(me);
if (me->timing) {
float oldelapsed = me->elapsed;
me->elapsed += tplus;
if ((int)oldelapsed != (int)me->elapsed)
status_bar(me->drawing, me->laststatus ? me->laststatus : "");
}
midend_set_timer(me);
}
float *midend_colours(midend *me, int *ncolours)
{
float *ret;
ret = me->ourgame->colours(me->frontend, ncolours);
assert(*ncolours >= 1);
{
int i;
/*
* Allow environment-based overrides for the standard
* colours by defining variables along the lines of
* `NET_COLOUR_4=6000c0'.
*/
for (i = 0; i < *ncolours; i++) {
char buf[80], *e;
unsigned int r, g, b;
int j, k;
sprintf(buf, "%s_COLOUR_%d", me->ourgame->name, i);
for (j = k = 0; buf[j]; j++)
if (!isspace((unsigned char)buf[j]))
buf[k++] = toupper((unsigned char)buf[j]);
buf[k] = '\0';
if ((e = getenv(buf)) != NULL &&
sscanf(e, "%2x%2x%2x", &r, &g, &b) == 3) {
ret[i*3 + 0] = r / 255.0F;
ret[i*3 + 1] = g / 255.0F;
ret[i*3 + 2] = b / 255.0F;
}
assert(0.0F <= ret[i*3 + 0] && ret[i*3 + 0] <= 1.0F);
assert(0.0F <= ret[i*3 + 1] && ret[i*3 + 1] <= 1.0F);
assert(0.0F <= ret[i*3 + 2] && ret[i*3 + 2] <= 1.0F);
}
}
return ret;
}
struct preset_menu *preset_menu_new(void)
{
struct preset_menu *menu = snew(struct preset_menu);
menu->n_entries = 0;
menu->entries_size = 0;
menu->entries = NULL;
return menu;
}
static struct preset_menu_entry *preset_menu_add(struct preset_menu *menu,
char *title)
{
struct preset_menu_entry *toret;
if (menu->n_entries >= menu->entries_size) {
menu->entries_size = menu->n_entries * 5 / 4 + 10;
menu->entries = sresize(menu->entries, menu->entries_size,
struct preset_menu_entry);
}
toret = &menu->entries[menu->n_entries++];
toret->title = title;
toret->params = NULL;
toret->submenu = NULL;
return toret;
}
struct preset_menu *preset_menu_add_submenu(struct preset_menu *parent,
char *title)
{
struct preset_menu_entry *entry = preset_menu_add(parent, title);
entry->submenu = preset_menu_new();
return entry->submenu;
}
void preset_menu_add_preset(struct preset_menu *parent,
char *title, game_params *params)
{
struct preset_menu_entry *entry = preset_menu_add(parent, title);
entry->params = params;
}
game_params *preset_menu_lookup_by_id(struct preset_menu *menu, int id)
{
int i;
game_params *retd;
for (i = 0; i < menu->n_entries; i++) {
if (id == menu->entries[i].id)
return menu->entries[i].params;
if (menu->entries[i].submenu &&
(retd = preset_menu_lookup_by_id(
menu->entries[i].submenu, id)) != NULL)
return retd;
}
return NULL;
}
static char *preset_menu_add_from_user_env(
midend *me, struct preset_menu *menu, char *p, bool top_level)
{
while (*p) {
char *name, *val;
game_params *preset;
name = p;
while (*p && *p != ':') p++;
if (*p) *p++ = '\0';
val = p;
while (*p && *p != ':') p++;
if (*p) *p++ = '\0';
if (!strcmp(val, "#")) {
/*
* Special case: either open a new submenu with the given
* title, or terminate the current submenu.
*/
if (*name) {
struct preset_menu *submenu =
preset_menu_add_submenu(menu, dupstr(name));
p = preset_menu_add_from_user_env(me, submenu, p, false);
} else {
/*
* If we get a 'close submenu' indication at the top
* level, there's not much we can do but quietly
* ignore it.
*/
if (!top_level)
return p;
}
continue;
}
preset = me->ourgame->default_params();
me->ourgame->decode_params(preset, val);
if (me->ourgame->validate_params(preset, true)) {
/* Drop this one from the list. */
me->ourgame->free_params(preset);
continue;
}
preset_menu_add_preset(menu, dupstr(name), preset);
}
return p;
}
static void preset_menu_alloc_ids(midend *me, struct preset_menu *menu)
{
int i;
for (i = 0; i < menu->n_entries; i++)
menu->entries[i].id = me->n_encoded_presets++;
for (i = 0; i < menu->n_entries; i++)
if (menu->entries[i].submenu)
preset_menu_alloc_ids(me, menu->entries[i].submenu);
}
static void preset_menu_encode_params(midend *me, struct preset_menu *menu)
{
int i;
for (i = 0; i < menu->n_entries; i++) {
if (menu->entries[i].params) {
me->encoded_presets[menu->entries[i].id] =
encode_params(me, menu->entries[i].params, true);
} else {
preset_menu_encode_params(me, menu->entries[i].submenu);
}
}
}
struct preset_menu *midend_get_presets(midend *me, int *id_limit)
{
int i;
if (me->preset_menu)
return me->preset_menu;
#if 0
/* Expect the game to implement exactly one of the two preset APIs */
assert(me->ourgame->fetch_preset || me->ourgame->preset_menu);
assert(!(me->ourgame->fetch_preset && me->ourgame->preset_menu));
#endif
if (me->ourgame->fetch_preset) {
char *name;
game_params *preset;
/* Simple one-level menu */
assert(!me->ourgame->preset_menu);
me->preset_menu = preset_menu_new();
for (i = 0; me->ourgame->fetch_preset(i, &name, &preset); i++)
preset_menu_add_preset(me->preset_menu, name, preset);
} else {
/* Hierarchical menu provided by the game backend */
me->preset_menu = me->ourgame->preset_menu();
}
{
/*
* Allow user extensions to the preset list by defining an
* environment variable <gamename>_PRESETS whose value is a
* colon-separated list of items, alternating between textual
* titles in the menu and encoded parameter strings. For
* example, "SOLO_PRESETS=2x3 Advanced:2x3da" would define
* just one additional preset for Solo.
*/
char buf[80], *e;
int j, k;
sprintf(buf, "%s_PRESETS", me->ourgame->name);
for (j = k = 0; buf[j]; j++)
if (!isspace((unsigned char)buf[j]))
buf[k++] = toupper((unsigned char)buf[j]);
buf[k] = '\0';
if ((e = getenv(buf)) != NULL) {
e = dupstr(e);
preset_menu_add_from_user_env(me, me->preset_menu, e, true);
sfree(e);
}
}
/*
* Finalise the menu: allocate an integer id to each entry, and
* store string encodings of the presets' parameters in
* me->encoded_presets.
*/
me->n_encoded_presets = 0;
preset_menu_alloc_ids(me, me->preset_menu);
me->encoded_presets = snewn(me->n_encoded_presets, char *);
for (i = 0; i < me->n_encoded_presets; i++)
me->encoded_presets[i] = NULL;
preset_menu_encode_params(me, me->preset_menu);
if (id_limit)
*id_limit = me->n_encoded_presets;
return me->preset_menu;
}
int midend_which_preset(midend *me)
{
char *encoding = encode_params(me, me->params, true);
int i, ret;
ret = -1;
for (i = 0; i < me->n_encoded_presets; i++)
if (me->encoded_presets[i] &&
!strcmp(encoding, me->encoded_presets[i])) {
ret = i;
break;
}
sfree(encoding);
return ret;
}
bool midend_wants_statusbar(midend *me)
{
return me->ourgame->wants_statusbar;
}
void midend_request_id_changes(midend *me, void (*notify)(void *), void *ctx)
{
me->game_id_change_notify_function = notify;
me->game_id_change_notify_ctx = ctx;
}
bool midend_get_cursor_location(midend *me,
int *x_out, int *y_out,
int *w_out, int *h_out)
{
int x, y, w, h;
x = y = -1;
w = h = 1;
if(me->ourgame->get_cursor_location)
me->ourgame->get_cursor_location(me->ui,
me->drawstate,
me->states[me->statepos-1].state,
me->params,
&x, &y, &w, &h);
if(x == -1 && y == -1)
return false;
if(x_out)
*x_out = x;
if(y_out)
*y_out = y;
if(w_out)
*w_out = w;
if(h_out)
*h_out = h;
return true;
}
void midend_supersede_game_desc(midend *me, const char *desc,
const char *privdesc)
{
/* Assert that the descriptions consists only of printable ASCII. */
assert_printable_ascii(desc);
if (privdesc)
assert_printable_ascii(privdesc);
sfree(me->desc);
sfree(me->privdesc);
me->desc = dupstr(desc);
me->privdesc = privdesc ? dupstr(privdesc) : NULL;
if (me->game_id_change_notify_function)
me->game_id_change_notify_function(me->game_id_change_notify_ctx);
}
config_item *midend_get_config(midend *me, int which, char **wintitle)
{
char *titlebuf, *parstr;
const char *rest;
config_item *ret;
char sep;
assert(wintitle);
titlebuf = snewn(40 + strlen(me->ourgame->name), char);
switch (which) {
case CFG_SETTINGS:
sprintf(titlebuf, "%s configuration", me->ourgame->name);
*wintitle = titlebuf;
return me->ourgame->configure(me->params);
case CFG_SEED:
case CFG_DESC:
if (!me->curparams) {
sfree(titlebuf);
return NULL;
}
sprintf(titlebuf, "%s %s selection", me->ourgame->name,
which == CFG_SEED ? "random" : "game");
*wintitle = titlebuf;
ret = snewn(2, config_item);
ret[0].type = C_STRING;
if (which == CFG_SEED)
ret[0].name = "Game random seed";
else
ret[0].name = "Game ID";
/*
* For CFG_DESC the text going in here will be a string
* encoding of the restricted parameters, plus a colon,
* plus the game description. For CFG_SEED it will be the
* full parameters, plus a hash, plus the random seed data.
* Either of these is a valid full game ID (although only
* the former is likely to persist across many code
* changes).
*/
parstr = encode_params(me, me->curparams, which == CFG_SEED);
assert(parstr);
if (which == CFG_DESC) {
rest = me->desc ? me->desc : "";
sep = ':';
} else {
rest = me->seedstr ? me->seedstr : "";
sep = '#';
}
ret[0].u.string.sval = snewn(strlen(parstr) + strlen(rest) + 2, char);
sprintf(ret[0].u.string.sval, "%s%c%s", parstr, sep, rest);
sfree(parstr);
ret[1].type = C_END;
ret[1].name = NULL;
return ret;
}
assert(!"We shouldn't be here");
return NULL;
}
static const char *midend_game_id_int(midend *me, const char *id, int defmode)
{
const char *error;
char *par = NULL;
const char *desc, *seed;
game_params *newcurparams, *newparams, *oldparams1, *oldparams2;
bool free_params;
seed = strchr(id, '#');
desc = strchr(id, ':');
if (desc && (!seed || desc < seed)) {
/*
* We have a colon separating parameters from game
* description. So `par' now points to the parameters
* string, and `desc' to the description string.
*/
par = snewn(desc-id + 1, char);
strncpy(par, id, desc-id);
par[desc-id] = '\0';
desc++;
seed = NULL;
} else if (seed && (!desc || seed < desc)) {
/*
* We have a hash separating parameters from random seed.
* So `par' now points to the parameters string, and `seed'
* to the seed string.
*/
par = snewn(seed-id + 1, char);
strncpy(par, id, seed-id);
par[seed-id] = '\0';
seed++;
desc = NULL;
} else {
/*
* We only have one string. Depending on `defmode', we take
* it to be either parameters, seed or description.
*/
if (defmode == DEF_SEED) {
seed = id;
par = NULL;
desc = NULL;
} else if (defmode == DEF_DESC) {
desc = id;
par = NULL;
seed = NULL;
} else {
par = dupstr(id);
seed = desc = NULL;
}
}
/*
* We must be reasonably careful here not to modify anything in
* `me' until we have finished validating things. This function
* must either return an error and do nothing to the midend, or
* return success and do everything; nothing in between is
* acceptable.
*/
newcurparams = newparams = oldparams1 = oldparams2 = NULL;
if (par) {
/*
* The params string may underspecify the game parameters, so
* we must first initialise newcurparams with a full set of
* params from somewhere else before we decode_params the
* input string over the top.
*
* But which set? It depends on what other data we have.
*
* If we've been given a _descriptive_ game id, then that may
* well underspecify by design, e.g. Solo game descriptions
* often start just '3x3:' without specifying one of Solo's
* difficulty settings, because it isn't necessary once a game
* has been generated (and you might not even know it, if
* you're manually transcribing a game description). In that
* situation, I've always felt that the best thing to set the
* difficulty to (for use if the user hits 'New Game' after
* pasting in that game id) is whatever it was previously set
* to. That is, we use whatever is already in me->params as
* the basis for our decoding of this input string.
*
* A random-seed based game id, however, should use the real,
* built-in default params, and not even check the
* <game>_DEFAULT environment setting, because when people
* paste each other random seeds - whether it's two users
* arranging to generate the same game at the same time to
* race solving them, or a user sending a bug report upstream
* - the whole point is for the random game id to always be
* interpreted the same way, even if it does underspecify.
*
* A parameter string typed in on its own, with no seed _or_
* description, gets treated the same way as a random seed,
* because again I think the most likely reason for doing that
* is to have a portable representation of a set of params.
*/
if (desc) {
newcurparams = me->ourgame->dup_params(me->params);
} else {
newcurparams = me->ourgame->default_params();
}
me->ourgame->decode_params(newcurparams, par);
error = me->ourgame->validate_params(newcurparams, desc == NULL);
if (error) {
me->ourgame->free_params(newcurparams);
return error;
}
oldparams1 = me->curparams;
/*
* Now filter only the persistent parts of this state into
* the long-term params structure, unless we've _only_
* received a params string in which case the whole lot is
* persistent.
*/
oldparams2 = me->params;
if (seed || desc) {
char *tmpstr;
newparams = me->ourgame->dup_params(me->params);
tmpstr = encode_params(me, newcurparams, false);
me->ourgame->decode_params(newparams, tmpstr);
sfree(tmpstr);
} else {
newparams = me->ourgame->dup_params(newcurparams);
}
free_params = true;
} else {
newcurparams = me->curparams;
newparams = me->params;
free_params = false;
}
if (desc) {
error = me->ourgame->validate_desc(newparams, desc);
if (error) {
if (free_params) {
if (newcurparams)
me->ourgame->free_params(newcurparams);
if (newparams)
me->ourgame->free_params(newparams);
}
return error;
}
}
/*
* Now we've got past all possible error points. Update the
* midend itself.
*/
me->params = newparams;
me->curparams = newcurparams;
if (oldparams1)
me->ourgame->free_params(oldparams1);
if (oldparams2)
me->ourgame->free_params(oldparams2);
sfree(me->desc);
sfree(me->privdesc);
me->desc = me->privdesc = NULL;
sfree(me->seedstr);
me->seedstr = NULL;
if (desc) {
me->desc = dupstr(desc);
me->genmode = GOT_DESC;
sfree(me->aux_info);
me->aux_info = NULL;
}
if (seed) {
me->seedstr = dupstr(seed);
me->genmode = GOT_SEED;
}
sfree(par);
me->newgame_can_store_undo = false;
return NULL;
}
const char *midend_game_id(midend *me, const char *id)
{
return midend_game_id_int(me, id, DEF_PARAMS);
}
char *midend_get_game_id(midend *me)
{
char *parstr, *ret;
parstr = encode_params(me, me->curparams, false);
assert(parstr);
assert(me->desc);
ret = snewn(strlen(parstr) + strlen(me->desc) + 2, char);
sprintf(ret, "%s:%s", parstr, me->desc);
sfree(parstr);
return ret;
}
char *midend_get_random_seed(midend *me)
{
char *parstr, *ret;
if (!me->seedstr)
return NULL;
parstr = encode_params(me, me->curparams, true);
assert(parstr);
ret = snewn(strlen(parstr) + strlen(me->seedstr) + 2, char);
sprintf(ret, "%s#%s", parstr, me->seedstr);
sfree(parstr);
return ret;
}
const char *midend_set_config(midend *me, int which, config_item *cfg)
{
const char *error;
game_params *params;
switch (which) {
case CFG_SETTINGS:
params = me->ourgame->custom_params(cfg);
error = me->ourgame->validate_params(params, true);
if (error) {
me->ourgame->free_params(params);
return error;
}
me->ourgame->free_params(me->params);
me->params = params;
break;
case CFG_SEED:
case CFG_DESC:
error = midend_game_id_int(me, cfg[0].u.string.sval,
(which == CFG_SEED ? DEF_SEED : DEF_DESC));
if (error)
return error;
break;
}
return NULL;
}
bool midend_can_format_as_text_now(midend *me)
{
if (me->ourgame->can_format_as_text_ever)
return me->ourgame->can_format_as_text_now(me->params);
else
return false;
}
char *midend_text_format(midend *me)
{
if (me->ourgame->can_format_as_text_ever && me->statepos > 0 &&
me->ourgame->can_format_as_text_now(me->params))
return me->ourgame->text_format(me->states[me->statepos-1].state);
else
return NULL;
}
const char *midend_solve(midend *me)
{
game_state *s;
const char *msg;
char *movestr;
if (!me->ourgame->can_solve)
return "This game does not support the Solve operation";
if (me->statepos < 1)
return "No game set up to solve"; /* _shouldn't_ happen! */
msg = NULL;
movestr = me->ourgame->solve(me->states[0].state,
me->states[me->statepos-1].state,
me->aux_info, &msg);
assert(movestr != UI_UPDATE);
if (!movestr) {
if (!msg)
msg = "Solve operation failed"; /* _shouldn't_ happen, but can */
return msg;
}
assert_printable_ascii(movestr);
s = me->ourgame->execute_move(me->states[me->statepos-1].state, movestr);
assert(s);
/*
* Now enter the solved state as the next move.
*/
midend_stop_anim(me);
midend_purge_states(me);
ensure(me);
me->states[me->nstates].state = s;
me->states[me->nstates].movestr = movestr;
me->states[me->nstates].movetype = SOLVE;
me->statepos = ++me->nstates;
if (me->ui)
me->ourgame->changed_state(me->ui,
me->states[me->statepos-2].state,
me->states[me->statepos-1].state);
me->dir = +1;
if (me->ourgame->flags & SOLVE_ANIMATES) {
me->oldstate = me->ourgame->dup_game(me->states[me->statepos-2].state);
me->anim_time =
me->ourgame->anim_length(me->states[me->statepos-2].state,
me->states[me->statepos-1].state,
+1, me->ui);
me->anim_pos = 0.0;
} else {
me->anim_time = 0.0;
midend_finish_move(me);
}
if (me->drawing)
midend_redraw(me);
midend_set_timer(me);
return NULL;
}
int midend_status(midend *me)
{
/*
* We should probably never be called when the state stack has no
* states on it at all - ideally, midends should never be left in
* that state for long enough to get put down and forgotten about.
* But if we are, I think we return _true_ - pedantically speaking
* a midend in that state is 'vacuously solved', and more
* practically, a user whose midend has been left in that state
* probably _does_ want the 'new game' option to be prominent.
*/
if (me->statepos == 0)
return +1;
return me->ourgame->status(me->states[me->statepos-1].state);
}
char *midend_rewrite_statusbar(midend *me, const char *text)
{
/*
* An important special case is that we are occasionally called
* with our own laststatus, to update the timer.
*/
if (me->laststatus != text) {
sfree(me->laststatus);
me->laststatus = dupstr(text);
}
if (me->ourgame->is_timed) {
char timebuf[100], *ret;
int min, sec;
sec = (int)me->elapsed;
min = sec / 60;
sec %= 60;
sprintf(timebuf, "[%d:%02d] ", min, sec);
ret = snewn(strlen(timebuf) + strlen(text) + 1, char);
strcpy(ret, timebuf);
strcat(ret, text);
return ret;
} else {
return dupstr(text);
}
}
#define SERIALISE_MAGIC "Simon Tatham's Portable Puzzle Collection"
#define SERIALISE_VERSION "1"
void midend_serialise(midend *me,
void (*write)(void *ctx, const void *buf, int len),
void *wctx)
{
int i;
/*
* Each line of the save file contains three components. First
* exactly 8 characters of header word indicating what type of
* data is contained on the line; then a colon followed by a
* decimal integer giving the length of the main string on the
* line; then a colon followed by the string itself (exactly as
* many bytes as previously specified, no matter what they
* contain). Then a newline (of reasonably flexible form).
*/
#define wr(h,s) do { \
char hbuf[80]; \
const char *str = (s); \
char lbuf[9]; \
copy_left_justified(lbuf, sizeof(lbuf), h); \
sprintf(hbuf, "%s:%d:", lbuf, (int)strlen(str)); \
assert_printable_ascii(hbuf); \
write(wctx, hbuf, strlen(hbuf)); \
assert_printable_ascii(str); \
write(wctx, str, strlen(str)); \
write(wctx, "\n", 1); \
} while (0)
/*
* Magic string identifying the file, and version number of the
* file format.
*/
wr("SAVEFILE", SERIALISE_MAGIC);
wr("VERSION", SERIALISE_VERSION);
/*
* The game name. (Copied locally to avoid const annoyance.)
*/
{
char *s = dupstr(me->ourgame->name);
wr("GAME", s);
sfree(s);
}
/*
* The current long-term parameters structure, in full.
*/
if (me->params) {
char *s = encode_params(me, me->params, true);
wr("PARAMS", s);
sfree(s);
}
/*
* The current short-term parameters structure, in full.
*/
if (me->curparams) {
char *s = encode_params(me, me->curparams, true);
wr("CPARAMS", s);
sfree(s);
}
/*
* The current game description, the privdesc, and the random seed.
*/
if (me->seedstr) {
/*
* Random seeds are not necessarily printable ASCII.
* Hex-encode the seed if necessary. Printable ASCII seeds
* are emitted unencoded for compatibility with older
* versions.
*/
int i;
for (i = 0; me->seedstr[i]; i++)
if (me->seedstr[i] < 32 || me->seedstr[i] >= 127)
break;
if (me->seedstr[i]) {
char *hexseed = bin2hex((unsigned char *)me->seedstr,
strlen(me->seedstr));
wr("HEXSEED", hexseed);
sfree(hexseed);
} else
wr("SEED", me->seedstr);
}
if (me->desc)
wr("DESC", me->desc);
if (me->privdesc)
wr("PRIVDESC", me->privdesc);
/*
* The game's aux_info. We obfuscate this to prevent spoilers
* (people are likely to run `head' or similar on a saved game
* file simply to find out what it is, and don't necessarily
* want to be told the answer to the puzzle!)
*/
if (me->aux_info) {
unsigned char *s1;
char *s2;
int len;
len = strlen(me->aux_info);
s1 = snewn(len, unsigned char);
memcpy(s1, me->aux_info, len);
obfuscate_bitmap(s1, len*8, false);
s2 = bin2hex(s1, len);
wr("AUXINFO", s2);
sfree(s2);
sfree(s1);
}
/*
* Any required serialisation of the game_ui.
*/
if (me->ui) {
char *s = me->ourgame->encode_ui(me->ui);
if (s) {
wr("UI", s);
sfree(s);
}
}
/*
* The game time, if it's a timed game.
*/
if (me->ourgame->is_timed) {
char buf[80];
sprintf(buf, "%g", me->elapsed);
wr("TIME", buf);
}
/*
* The length of, and position in, the states list.
*/
{
char buf[80];
sprintf(buf, "%d", me->nstates);
wr("NSTATES", buf);
assert(me->statepos >= 1 && me->statepos <= me->nstates);
sprintf(buf, "%d", me->statepos);
wr("STATEPOS", buf);
}
/*
* For each state after the initial one (which we know is
* constructed from either privdesc or desc), enough
* information for execute_move() to reconstruct it from the
* previous one.
*/
for (i = 1; i < me->nstates; i++) {
assert(me->states[i].movetype != NEWGAME); /* only state 0 */
switch (me->states[i].movetype) {
case MOVE:
wr("MOVE", me->states[i].movestr);
break;
case SOLVE:
wr("SOLVE", me->states[i].movestr);
break;
case RESTART:
wr("RESTART", me->states[i].movestr);
break;
}
}
#undef wr
}
/*
* Internal version of midend_deserialise, taking an extra check
* function to be called just before beginning to install things in
* the midend.
*
* Like midend_deserialise proper, this function returns NULL on
* success, or an error message.
*/
static const char *midend_deserialise_internal(
midend *me, bool (*read)(void *ctx, void *buf, int len), void *rctx,
const char *(*check)(void *ctx, midend *, const struct deserialise_data *),
void *cctx)
{
struct deserialise_data data;
int gotstates = 0;
bool started = false;
int i;
char *val = NULL;
/* Initially all errors give the same report */
const char *ret = "Data does not appear to be a saved game file";
data.seed = data.parstr = data.desc = data.privdesc = NULL;
data.auxinfo = data.uistr = data.cparstr = NULL;
data.elapsed = 0.0F;
data.params = data.cparams = NULL;
data.ui = NULL;
data.states = NULL;
data.nstates = 0;
data.statepos = -1;
/*
* Loop round and round reading one key/value pair at a time
* from the serialised stream, until we have enough game states
* to finish.
*/
while (data.nstates <= 0 || data.statepos < 0 ||
gotstates < data.nstates-1) {
char key[9], c;
int len;
do {
if (!read(rctx, key, 1)) {
/* unexpected EOF */
goto cleanup;
}
} while (key[0] == '\r' || key[0] == '\n');
if (!read(rctx, key+1, 8)) {
/* unexpected EOF */
goto cleanup;
}
if (key[8] != ':') {
if (started)
ret = "Data was incorrectly formatted for a saved game file";
goto cleanup;
}
len = strcspn(key, ": ");
assert(len <= 8);
key[len] = '\0';
len = 0;
while (1) {
if (!read(rctx, &c, 1)) {
/* unexpected EOF */
goto cleanup;
}
if (c == ':') {
break;
} else if (c >= '0' && c <= '9') {
len = (len * 10) + (c - '0');
} else {
if (started)
ret = "Data was incorrectly formatted for a"
" saved game file";
goto cleanup;
}
}
val = snewn(len+1, char);
if (!read(rctx, val, len)) {
if (started)
goto cleanup;
}
val[len] = '\0';
if (!started) {
if (strcmp(key, "SAVEFILE") || strcmp(val, SERIALISE_MAGIC)) {
/* ret already has the right message in it */
goto cleanup;
}
/* Now most errors are this one, unless otherwise specified */
ret = "Saved data ended unexpectedly";
started = true;
} else {
if (!strcmp(key, "VERSION")) {
if (strcmp(val, SERIALISE_VERSION)) {
ret = "Cannot handle this version of the saved game"
" file format";
goto cleanup;
}
} else if (!strcmp(key, "GAME")) {
if (strcmp(val, me->ourgame->name)) {
ret = "Save file is from a different game";
goto cleanup;
}
} else if (!strcmp(key, "PARAMS")) {
sfree(data.parstr);
data.parstr = val;
val = NULL;
} else if (!strcmp(key, "CPARAMS")) {
sfree(data.cparstr);
data.cparstr = val;
val = NULL;
} else if (!strcmp(key, "HEXSEED")) {
unsigned char *tmp;
int len = strlen(val) / 2; /* length in bytes */
tmp = hex2bin(val, len);
sfree(data.seed);
data.seed = snewn(len + 1, char);
memcpy(data.seed, tmp, len);
data.seed[len] = '\0';
sfree(tmp);
} else if (!strcmp(key, "SEED")) {
sfree(data.seed);
data.seed = val;
val = NULL;
} else if (!strcmp(key, "DESC")) {
sfree(data.desc);
data.desc = val;
val = NULL;
} else if (!strcmp(key, "PRIVDESC")) {
sfree(data.privdesc);
data.privdesc = val;
val = NULL;
} else if (!strcmp(key, "AUXINFO")) {
unsigned char *tmp;
int len = strlen(val) / 2; /* length in bytes */
tmp = hex2bin(val, len);
obfuscate_bitmap(tmp, len*8, true);
sfree(data.auxinfo);
data.auxinfo = snewn(len + 1, char);
memcpy(data.auxinfo, tmp, len);
data.auxinfo[len] = '\0';
sfree(tmp);
} else if (!strcmp(key, "UI")) {
sfree(data.uistr);
data.uistr = val;
val = NULL;
} else if (!strcmp(key, "TIME")) {
data.elapsed = (float)atof(val);
} else if (!strcmp(key, "NSTATES")) {
if (data.states) {
ret = "Two state counts provided in save file";
goto cleanup;
}
data.nstates = atoi(val);
if (data.nstates <= 0) {
ret = "Number of states in save file was negative";
goto cleanup;
}
data.states = snewn(data.nstates, struct midend_state_entry);
for (i = 0; i < data.nstates; i++) {
data.states[i].state = NULL;
data.states[i].movestr = NULL;
data.states[i].movetype = NEWGAME;
}
} else if (!strcmp(key, "STATEPOS")) {
data.statepos = atoi(val);
} else if (!strcmp(key, "MOVE") ||
!strcmp(key, "SOLVE") ||
!strcmp(key, "RESTART")) {
if (!data.states) {
ret = "No state count provided in save file";
goto cleanup;
}
gotstates++;
if (!strcmp(key, "MOVE"))
data.states[gotstates].movetype = MOVE;
else if (!strcmp(key, "SOLVE"))
data.states[gotstates].movetype = SOLVE;
else
data.states[gotstates].movetype = RESTART;
data.states[gotstates].movestr = val;
val = NULL;
}
}
sfree(val);
val = NULL;
}
data.params = me->ourgame->default_params();
if (!data.parstr) {
ret = "Long-term parameters in save file are missing";
goto cleanup;
}
me->ourgame->decode_params(data.params, data.parstr);
if (me->ourgame->validate_params(data.params, true)) {
ret = "Long-term parameters in save file are invalid";
goto cleanup;
}
data.cparams = me->ourgame->default_params();
if (!data.cparstr) {
ret = "Short-term parameters in save file are missing";
goto cleanup;
}
me->ourgame->decode_params(data.cparams, data.cparstr);
if (me->ourgame->validate_params(data.cparams, false)) {
ret = "Short-term parameters in save file are invalid";
goto cleanup;
}
if (data.seed && me->ourgame->validate_params(data.cparams, true)) {
/*
* The seed's no use with this version, but we can perfectly
* well use the rest of the data.
*/
sfree(data.seed);
data.seed = NULL;
}
if (!data.desc) {
ret = "Game description in save file is missing";
goto cleanup;
} else if (me->ourgame->validate_desc(data.cparams, data.desc)) {
ret = "Game description in save file is invalid";
goto cleanup;
}
if (data.privdesc &&
me->ourgame->validate_desc(data.cparams, data.privdesc)) {
ret = "Game private description in save file is invalid";
goto cleanup;
}
if (data.statepos < 1 || data.statepos > data.nstates) {
ret = "Game position in save file is out of range";
goto cleanup;
}
if (!data.states) {
ret = "No state count provided in save file";
goto cleanup;
}
data.states[0].state = me->ourgame->new_game(
me, data.cparams, data.privdesc ? data.privdesc : data.desc);
for (i = 1; i < data.nstates; i++) {
assert(data.states[i].movetype != NEWGAME);
switch (data.states[i].movetype) {
case MOVE:
case SOLVE:
data.states[i].state = me->ourgame->execute_move(
data.states[i-1].state, data.states[i].movestr);
if (data.states[i].state == NULL) {
ret = "Save file contained an invalid move";
goto cleanup;
}
break;
case RESTART:
if (me->ourgame->validate_desc(
data.cparams, data.states[i].movestr)) {
ret = "Save file contained an invalid restart move";
goto cleanup;
}
data.states[i].state = me->ourgame->new_game(
me, data.cparams, data.states[i].movestr);
break;
}
}
data.ui = me->ourgame->new_ui(data.states[0].state);
me->ourgame->decode_ui(data.ui, data.uistr);
/*
* Run the externally provided check function, and abort if it
* returns an error message.
*/
if (check && (ret = check(cctx, me, &data)) != NULL)
goto cleanup; /* error message is already in ret */
/*
* Now we've run out of possible error conditions, so we're
* ready to start overwriting the real data in the current
* midend. We'll do this by swapping things with the local
* variables, so that the same cleanup code will free the old
* stuff.
*/
{
char *tmp;
tmp = me->desc;
me->desc = data.desc;
data.desc = tmp;
tmp = me->privdesc;
me->privdesc = data.privdesc;
data.privdesc = tmp;
tmp = me->seedstr;
me->seedstr = data.seed;
data.seed = tmp;
tmp = me->aux_info;
me->aux_info = data.auxinfo;
data.auxinfo = tmp;
}
me->genmode = GOT_NOTHING;
me->statesize = data.nstates;
data.nstates = me->nstates;
me->nstates = me->statesize;
{
struct midend_state_entry *tmp;
tmp = me->states;
me->states = data.states;
data.states = tmp;
}
me->statepos = data.statepos;
/*
* Don't save the "new game undo/redo" state. So "new game" twice or
* (in some environments) switching away and back, will make a
* "new game" irreversible. Maybe in the future we will have a
* more sophisticated way to decide when to discard the previous
* game state.
*/
me->newgame_undo.len = 0;
me->newgame_redo.len = 0;
{
game_params *tmp;
tmp = me->params;
me->params = data.params;
data.params = tmp;
tmp = me->curparams;
me->curparams = data.cparams;
data.cparams = tmp;
}
me->oldstate = NULL;
me->anim_time = me->anim_pos = me->flash_time = me->flash_pos = 0.0F;
me->dir = 0;
{
game_ui *tmp;
tmp = me->ui;
me->ui = data.ui;
data.ui = tmp;
}
me->elapsed = data.elapsed;
me->pressed_mouse_button = 0;
midend_set_timer(me);
if (me->drawstate)
me->ourgame->free_drawstate(me->drawing, me->drawstate);
me->drawstate =
me->ourgame->new_drawstate(me->drawing,
me->states[me->statepos-1].state);
me->first_draw = true;
midend_size_new_drawstate(me);
if (me->game_id_change_notify_function)
me->game_id_change_notify_function(me->game_id_change_notify_ctx);
ret = NULL; /* success! */
cleanup:
sfree(val);
sfree(data.seed);
sfree(data.parstr);
sfree(data.cparstr);
sfree(data.desc);
sfree(data.privdesc);
sfree(data.auxinfo);
sfree(data.uistr);
if (data.params)
me->ourgame->free_params(data.params);
if (data.cparams)
me->ourgame->free_params(data.cparams);
if (data.ui)
me->ourgame->free_ui(data.ui);
if (data.states) {
int i;
for (i = 0; i < data.nstates; i++) {
if (data.states[i].state)
me->ourgame->free_game(data.states[i].state);
sfree(data.states[i].movestr);
}
sfree(data.states);
}
return ret;
}
const char *midend_deserialise(
midend *me, bool (*read)(void *ctx, void *buf, int len), void *rctx)
{
return midend_deserialise_internal(me, read, rctx, NULL, NULL);
}
/*
* This function examines a saved game file just far enough to
* determine which game type it contains. It returns NULL on success
* and the game name string in 'name' (which will be dynamically
* allocated and should be caller-freed), or an error message on
* failure.
*/
const char *identify_game(char **name,
bool (*read)(void *ctx, void *buf, int len),
void *rctx)
{
int nstates = 0, statepos = -1, gotstates = 0;
bool started = false;
char *val = NULL;
/* Initially all errors give the same report */
const char *ret = "Data does not appear to be a saved game file";
*name = NULL;
/*
* Loop round and round reading one key/value pair at a time from
* the serialised stream, until we've found the game name.
*/
while (nstates <= 0 || statepos < 0 || gotstates < nstates-1) {
char key[9], c;
int len;
do {
if (!read(rctx, key, 1)) {
/* unexpected EOF */
goto cleanup;
}
} while (key[0] == '\r' || key[0] == '\n');
if (!read(rctx, key+1, 8)) {
/* unexpected EOF */
goto cleanup;
}
if (key[8] != ':') {
if (started)
ret = "Data was incorrectly formatted for a saved game file";
goto cleanup;
}
len = strcspn(key, ": ");
assert(len <= 8);
key[len] = '\0';
len = 0;
while (1) {
if (!read(rctx, &c, 1)) {
/* unexpected EOF */
goto cleanup;
}
if (c == ':') {
break;
} else if (c >= '0' && c <= '9') {
len = (len * 10) + (c - '0');
} else {
if (started)
ret = "Data was incorrectly formatted for a"
" saved game file";
goto cleanup;
}
}
val = snewn(len+1, char);
if (!read(rctx, val, len)) {
if (started)
goto cleanup;
}
val[len] = '\0';
if (!started) {
if (strcmp(key, "SAVEFILE") || strcmp(val, SERIALISE_MAGIC)) {
/* ret already has the right message in it */
goto cleanup;
}
/* Now most errors are this one, unless otherwise specified */
ret = "Saved data ended unexpectedly";
started = true;
} else {
if (!strcmp(key, "VERSION")) {
if (strcmp(val, SERIALISE_VERSION)) {
ret = "Cannot handle this version of the saved game"
" file format";
goto cleanup;
}
} else if (!strcmp(key, "GAME")) {
*name = dupstr(val);
ret = NULL;
goto cleanup;
}
}
sfree(val);
val = NULL;
}
cleanup:
sfree(val);
return ret;
}
const char *midend_print_puzzle(midend *me, document *doc, bool with_soln)
{
game_state *soln = NULL;
if (me->statepos < 1)
return "No game set up to print";/* _shouldn't_ happen! */
if (with_soln) {
const char *msg;
char *movestr;
if (!me->ourgame->can_solve)
return "This game does not support the Solve operation";
msg = "Solve operation failed";/* game _should_ overwrite on error */
movestr = me->ourgame->solve(me->states[0].state,
me->states[me->statepos-1].state,
me->aux_info, &msg);
if (!movestr)
return msg;
soln = me->ourgame->execute_move(me->states[me->statepos-1].state,
movestr);
assert(soln);
sfree(movestr);
} else
soln = NULL;
/*
* This call passes over ownership of the two game_states and
* the game_params. Hence we duplicate the ones we want to
* keep, and we don't have to bother freeing soln if it was
* non-NULL.
*/
document_add_puzzle(doc, me->ourgame,
me->ourgame->dup_params(me->curparams),
me->ourgame->dup_game(me->states[0].state), soln);
return NULL;
}