X-Git-Url: https://jxself.org/git/?p=open-adventure.git;a=blobdiff_plain;f=saveresume.c;h=b03a6215c5c6d11b862add5700eb91a39e5d551e;hp=a3dbe968ebdaf4838ea2552d6c77b6e951143721;hb=6de0149f9e33a170c8ceb28466d3221be230fb96;hpb=63152e67145eb22371a45a4ae6d3ba35bd221847 diff --git a/saveresume.c b/saveresume.c index a3dbe96..b03a621 100644 --- a/saveresume.c +++ b/saveresume.c @@ -1,17 +1,24 @@ +/* + * Saving and resuming. + * + * (ESR) This replaces a bunch of particularly nasty FORTRAN-derived code; + * see the history.adoc file in the source distribution for discussion. + * + * Copyright (c) 1977, 2005 by Will Crowther and Don Woods + * Copyright (c) 2017 by Eric S. Raymond + * SPDX-License-Identifier: BSD-2-clause + */ + #include #include #include #include +#include #include "advent.h" #include "dungeon.h" -/* - * (ESR) This replaces a bunch of particularly nasty FORTRAN-derived code; - * see the history.adoc file in the source distribution for discussion. - */ - -#define VRSION 27 /* bump on save format change */ +#define VRSION 28 /* bump on save format change */ /* * If you change the first three members, the resume function may not properly @@ -20,23 +27,23 @@ * when you do that. */ struct save_t { - long savetime; - long mode; /* not used, must be present for version detection */ - long version; + int64_t savetime; + int32_t mode; /* not used, must be present for version detection */ + int32_t version; struct game_t game; }; struct save_t save; #define IGNORE(r) do{if (r){}}while(0) -int savefile(FILE *fp, long version) +int savefile(FILE *fp, int32_t version) /* Save game to file. No input or output from user. */ { save.savetime = time(NULL); save.mode = -1; save.version = (version == 0) ? VRSION : version; - memcpy(&save.game, &game, sizeof(struct game_t)); + save.game = game; IGNORE(fwrite(&save, sizeof(struct save_t), 1, fp)); return (0); } @@ -105,6 +112,8 @@ int resume(void) return restore(fp); } +bool is_valid(struct game_t*); + int restore(FILE* fp) { /* Read and restore game state from file, assuming @@ -118,10 +127,124 @@ int restore(FILE* fp) fclose(fp); if (save.version != VRSION) { rspeak(VERSION_SKEW, save.version / 10, MOD(save.version, 10), VRSION / 10, MOD(VRSION, 10)); - } else { - memcpy(&game, &save.game, sizeof(struct game_t)); + } else if (is_valid(&save.game)) { + game = save.game; } return GO_TOP; } +bool is_valid(struct game_t* valgame) +{ + /* Save files can be roughly grouped into three groups: + * With valid, reaceable state, with valid, but unreachable + * state and with invaild state. We check that state is + * valid: no states are outside minimal or maximal value + */ + + /* Prevent division by zero */ + if (valgame->abbnum == 0) { + return false; + } + + /* Check for RNG overflow. Truncate */ + if (valgame->lcg_x >= LCG_M) { + valgame->lcg_x %= LCG_M; + } + + /* Check for RNG underflow. Transpose */ + if (valgame->lcg_x < LCG_M) { + valgame->lcg_x = LCG_M + (valgame->lcg_x % LCG_M); + } + + /* Bounds check for locations */ + if ( valgame->chloc < -1 || valgame->chloc > NLOCATIONS || + valgame->chloc2 < -1 || valgame->chloc2 > NLOCATIONS || + valgame->loc < 0 || valgame->loc > NLOCATIONS || + valgame->newloc < 0 || valgame->newloc > NLOCATIONS || + valgame->oldloc < 0 || valgame->oldloc > NLOCATIONS || + valgame->oldlc2 < 0 || valgame->oldlc2 > NLOCATIONS) { + return false; + } + /* Bounds check for location arrays */ + for (int i = 0; i <= NDWARVES; i++) { + if (valgame->dloc[i] < -1 || valgame->dloc[i] > NLOCATIONS || + valgame->odloc[i] < -1 || valgame->odloc[i] > NLOCATIONS) { + return false; + } + } + + for (int i = 0; i <= NOBJECTS; i++) { + if (valgame->place[i] < -1 || valgame->place[i] > NLOCATIONS || + valgame->fixed[i] < -1 || valgame->fixed[i] > NLOCATIONS) { + return false; + } + } + + /* Bounds check for dwarves */ + if (valgame->dtotal < 0 || valgame->dtotal > NDWARVES || + valgame->dkill < 0 || valgame->dkill > NDWARVES) { + return false; + } + + /* Validate that we didn't die too many times in save */ + if (valgame->numdie >= NDEATHS) { + return false; + } + + /* Recalculate tally, throw the towel if in disagreement */ + long temp_tally = 0; + for (int treasure = 1; treasure <= NOBJECTS; treasure++) { + if (objects[treasure].is_treasure) { + if (valgame->prop[treasure] == STATE_NOTFOUND) { + ++temp_tally; + } + } + } + if (temp_tally != valgame->tally) { + return false; + } + + /* Check that properties of objects aren't beyond expected */ + for (obj_t obj = 0; obj <= NOBJECTS; obj++) { + if (valgame->prop[obj] < STATE_NOTFOUND || valgame->prop[obj] > 1) { + switch (obj) { + case RUG: + case DRAGON: + case BIRD: + case BOTTLE: + case PLANT: + case PLANT2: + case TROLL: + case URN: + case EGGS: + case VASE: + case CHAIN: + if (valgame->prop[obj] == 2) // There are multiple different states, but it's convenient to clump them together + continue; + /* FALLTHRU */ + case BEAR: + if (valgame->prop[BEAR] == CONTENTED_BEAR || valgame->prop[BEAR] == BEAR_DEAD) + continue; + /* FALLTHRU */ + default: + return false; + } + } + } + + /* Check that values in linked lists for objects in locations are inside bounds */ + for (loc_t loc = LOC_NOWHERE; loc <= NLOCATIONS; loc++) { + if (valgame->atloc[loc] < NO_OBJECT || valgame->atloc[loc] > NOBJECTS * 2) { + return false; + } + } + for (obj_t obj = 0; obj <= NOBJECTS * 2; obj++ ) { + if (valgame->link[obj] < NO_OBJECT || valgame->link[obj] > NOBJECTS * 2) { + return false; + } + } + + return true; +} + /* end */