Moved seed initialization into rrand().

[plomrogue] / roguelike.c

diff --git a/roguelike.c b/roguelike.c
index 532ae70ec08993b5b8666773e3f725f10a3e1614..c91c407360c100d71921f82ab39631b1d676197e 100644 (file)
--- a/roguelike.c
+++ b/roguelike.c
@@ -1,4 +1,5 @@
 #include <stdlib.h>
+#include <limits.h>
 #include <stdint.h>
 #include <ncurses.h>
 #include <string.h>
@@ -7,6 +8,15 @@
 #include "roguelike.h"
 #include "keybindings.h"
 
+uint16_t rrand() {
+// Pseudo-random number generator (LGC algorithm). Use instead of rand() to ensure portable predictability.
+  uint32_t a   = 1103515245;      // Values for a and b as recommended by POSIX.1-2001 (see man page rand(3)).
+  uint16_t b   =      12345;
+  uint32_t mod = 2147483648;
+  static uint32_t seed = 0;
+  seed = ((seed * a) + b) % mod;
+  return (seed / 65536); }        // Ignore least significant 16 bits (they are less random).
+
 void toggle_window (struct WinMeta * win_meta, struct Win * win) {
 // Toggle display of window win.
   if (0 != win->curses)
@@ -42,7 +52,7 @@ struct Map init_map () {
   for (y = 0; y < map.height; y++)
     for (x = 0; x < map.width; x++) {
       terrain = '.';
-      ran = rand();
+      ran = rrand();
       if (   0 == ran % ((x*x) / 3 + 1)
           || 0 == ran % ((y*y) / 3 + 1)
           || 0 == ran % ((map.width - x - 1) * (map.width - x - 1) / 3 + 1)
@@ -65,7 +75,7 @@ void map_scroll (struct Map * map, char dir) {
 void next_turn (struct World * world) {
 // Increment turn and move enemy.
   world->turn++;
-  char d = rand() % 5;
+  char d = rrand() % 5;
   char ty = world->monster->y;
   char tx = world->monster->x;
   if (1 == d)
@@ -143,11 +153,45 @@ void move_player (struct World * world, char d) {
   prev = success * d;
   next_turn (world); }
 
-void player_wait(struct World * world) {
+void player_wait (struct World * world) {
 // Make player wait one turn.
   next_turn (world);
   update_log (world, "\nYou wait."); }
 
+void save_map (struct Map * map) {
+// Save map to file "map".
+  FILE * file = fopen("map", "w");
+  fputc(map->width / CHAR_MAX, file);
+  fputc(map->width % CHAR_MAX, file);
+  uint16_t y, x;
+  for (y = 0; y < map->height; y++)
+    for (x = 0; x < map->width; x++)
+      fputc(map->cells[y * map->width + x], file);
+  fclose(file); }
+
+struct Map load_map () {
+// Load map from file.
+  FILE * file = fopen("map", "r");
+  struct Map map;
+  map.width = (fgetc(file) * CHAR_MAX) + fgetc(file);
+  long pos = ftell(file);
+  int c = fgetc(file);
+  uint32_t i = 0;
+  while (EOF != c) {
+    i++;
+    c = fgetc(file); }
+  map.cells = malloc(i * sizeof(char));
+  map.height = i / map.width;
+  fseek(file, pos, SEEK_SET);
+  c = fgetc(file);
+  i = 0;
+  while (EOF != c) {
+    map.cells[i] = (char) c;
+    c = fgetc(file);
+    i++; }
+  fclose(file);
+  return map; }
+
 int main () {
   struct World world;
   init_keybindings(&world);
@@ -218,6 +262,10 @@ int main () {
       keyswin_move_selection (&world, 'd');
     else if (key == get_action_key(world.keybindings, "keys mod"))
       keyswin_mod_key (&world, &win_meta);
+    else if (key == get_action_key(world.keybindings, "load map"))
+      map = load_map();
+    else if (key == get_action_key(world.keybindings, "save map"))
+      save_map(&map);
     else if (key == get_action_key(world.keybindings, "map up"))
       map_scroll (&map, 'n');
     else if (key == get_action_key(world.keybindings, "map down"))