main() handles file IO now safely, exits on errors; also analogously re-phrased error...

[plomrogue] / src / main.c

diff --git a/src/main.c b/src/main.c
index 7096f6c65a536f7c9d74323602e0526997099ced..3ca00e70cda19aef478759e409b58cfca4ad1f85 100644 (file)
--- a/src/main.c
+++ b/src/main.c
@@ -6,6 +6,7 @@
 #include <ncurses.h> /* for initscr(), noecho(), curs_set(), keypad(), raw() */
 #include <time.h> /* for time() */
 #include <unistd.h> /* for getopt(), optarg */
+#include <stdint.h> /* for uint8_t */
 #include "windows.h" /* for structs WinMeta, Win, init_win(), init_win_meta(),
                       * draw_all_wins()
                       */
@@ -13,9 +14,7 @@
                         * draw_log_win()
                         */
 #include "keybindings.h" /* for initkeybindings(), get_action_key() */
-#include "readwrite.h" /* for read_uint16_bigendian, read_uint32_bigendian,
-                        * write_uint32_bigendian
-                        */
+#include "readwrite.h" /* for [read/write]_uint[8/16/32][_bigendian]() */
 #include "map_objects.h" /* for structs Monster, Item, Player,
                           * init_map_object_defs(), read_map_objects(),
                           * build_map_objects()
@@ -64,41 +63,76 @@ int main(int argc, char *argv[])
     init_map_object_defs(&world, "defs");
 
     /* For interactive mode, try to load world state from savefile. */
+    char * err_o = "Error loading game: "
+                   "Unable to open 'savefile' for reading.";
+    char * err_r = "Error loading game: "
+                   "Trouble reading from opened 'savefile'.";
+    char * err_c = "Error loading game: "
+                   "Unable to close opened 'savefile'.";
+    char * savefile = "savefile";
     FILE * file;
-    if (1 == world.interactive && 0 == access("savefile", F_OK))
+    if (1 == world.interactive && 0 == access(savefile, F_OK))
     {
-        file = fopen("savefile", "r");
-        world.seed = read_uint32_bigendian(file);
-        world.turn = read_uint32_bigendian(file);
-        player.pos.y = read_uint16_bigendian(file) - 1;
-        player.pos.x = read_uint16_bigendian(file) - 1;
-        player.hitpoints = fgetc(file);
-        read_map_objects(&world, &world.monster, file);
-        read_map_objects(&world, &world.item,    file);
-        fclose(file);
+        file = fopen(savefile, "r");
+        exit_err(0 == file, &world, err_o);
+        if (   read_uint32_bigendian(file, &world.seed)
+            || read_uint32_bigendian(file, &world.turn)
+            || read_uint16_bigendian(file, &player.pos.y)
+            || read_uint16_bigendian(file, &player.pos.x)
+            || read_uint8(file, &player.hitpoints)
+            || read_map_objects(&world, &world.monster, file)
+            || read_map_objects(&world, &world.item,    file))
+        {
+            exit_err(1, &world, err_r);
+        }
+        exit_err(fclose(file), &world, err_c);
+        player.pos.y--;
+        player.pos.x--;
     }
 
     /* For non-interactive mode, try to load world state from record file. */
     else
     {
+        err_o = "Error loading record file: "
+                "Unable to open file 'record' for reading.";
+        err_r = "Error loading record file: "
+                "Trouble reading from opened file 'record'.";
+        char * recordfile = "record";
         world.turn = 1;
         if (0 == world.interactive)
         {
-            file = fopen("record", "r");
-            world.seed = read_uint32_bigendian(file);
+            file = fopen(recordfile, "r");
+            exit_err(0 == file, &world, err_o);
+            exit_err(read_uint32_bigendian(file, &world.seed), &world, err_r);
+        }
+
+        /* For interactive-mode in newly started world, generate a start seed
+         * from the current time.
+         */
+        else
+        {
+            world.seed = time(NULL);
+
+            char * err_x = "Error recording new seed: "
+                           "A file 'record' already exists, when it shouldn't.";
+            err_o        = "Error recording new seed: "
+                           "Unable to open 'record_tmp' file for writing.";
+            char * err_w = "Error recording new seed: "
+                           "Trouble writing to opened 'record_tmp' file.";
+            err_c        = "Error recording new seed: "
+                           "Unable to close opened file 'record_tmp'.";
+            char * err_m = "Error recording new seed: "
+                           "Unable to rename file 'record_tmp' to 'record'.";
+            char * recordfile_tmp = "record_tmp";
+            exit_err(!access(recordfile, F_OK), &world, err_x);
+            file = fopen(recordfile_tmp, "w");
+            exit_err(0 == file, &world, err_o);
+            exit_err(write_uint32_bigendian(world.seed, file), &world, err_w);
+            exit_err(fclose(file), &world, err_c);
+            exit_err(rename(recordfile_tmp, recordfile), &world, err_m);
         }
+    }
 
-      /* For interactive-mode in newly started world, generate a start seed
-       * from the current time.
-       */
-      else
-      {
-          file = fopen("record", "w");
-          world.seed = time(NULL);
-          write_uint32_bigendian(world.seed, file);
-          fclose(file);
-      }
-  }
 
     /* Generate map from seed and, if newly generated world, start positions of
      * actors.
@@ -147,8 +181,8 @@ int main(int argc, char *argv[])
 
     /* Replay mode. */
     int key;
-    unsigned char quit_called = 0;
-    unsigned char await_actions = 1;
+    uint8_t quit_called = 0;
+    uint8_t await_actions = 1;
     if (0 == world.interactive)
     {
         int action;
@@ -201,6 +235,8 @@ int main(int argc, char *argv[])
                                              &win_map, &win_info, &win_log);
                 if (1 == quit_called)
                 {
+                    err_c = "Error closing read 'record' file.";
+                    exit_err(fclose(file), &world, err_c);
                     exit_game(&world);
                 }
             }