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

[plomrogue] / src / misc.c

diff --git a/src/misc.c b/src/misc.c
index cfa43caf14b7054e682d631a20b85e328a1bfbd9..6f8c6c766ac1b0807b64e73a8524e4c8fb3c1f19 100644 (file)
--- a/src/misc.c
+++ b/src/misc.c
@@ -1,6 +1,8 @@
 /* misc.c */
 
 #include "misc.h"
+#include <stdio.h> /* for rename() */
+#include <unistd.h> /* for unlink(), acess() */
 #include <stdlib.h> /* for calloc(), free() */
 #include <string.h> /* for strlen(), strcmp(), memcpy() */
 #include <stdint.h> /* for uint8_t */
@@ -112,12 +114,28 @@ extern uint16_t center_offset(uint16_t pos, uint16_t mapsize,
 
 extern void turn_over(struct World * world, char action)
 {
+    char * err_open  = "Error recording move: "
+                       "Unable to open file 'record_tmp' for appending.";
+    char * err_write = "Error recording move: "
+                       "Trouble writing to opened file 'record_tmp'.";
+    char * err_close = "Error recording move: "
+                       "Unable to close opened file 'record_tmp'.";
+    char * err_unl   = "Error recording move: "
+                       "Unable to unlink old file 'record'.";
+    char * err_move  = "Error recording move: "
+                        "Unable to rename file 'record_tmp' to 'record'.";
+    char * recordfile_tmp = "record_tmp";
+    char * recordfile     = "record";
     if (1 == world->interactive)
     {
-        FILE * file = fopen("record", "a");
-        exit_err(write_uint8(action, file), world, "Record writing failure.");
-        fclose(file);
+        FILE * file = fopen(recordfile_tmp, "a");
+        exit_err(0 == file, world, err_open);
+        exit_err(write_uint8(action, file), world, err_write);
+        exit_err(fclose(file), world, err_close);
+        exit_err(unlink(recordfile), world, err_unl);
+        exit_err(rename(recordfile_tmp, recordfile), world, err_move);
     }
+
     world->turn++;
     rrand_seed(world->seed * world->turn);
     struct Monster * monster;
@@ -133,17 +151,36 @@ extern void turn_over(struct World * world, char action)
 
 extern void save_game(struct World * world)
 {
-    uint8_t err;
-    FILE * file = fopen("savefile", "w");
-    err = write_uint32_bigendian(world->seed, file);
-    err = err | write_uint32_bigendian(world->turn, file);
-    err = err | write_uint16_bigendian(world->player->pos.y + 1, file);
-    err = err | write_uint16_bigendian(world->player->pos.x + 1, file);
-    err = err | write_uint8(world->player->hitpoints, file);
-    err = err | write_map_objects(world, world->monster, file);
-    err = err | write_map_objects(world, world->item, file);
-    exit_err(err, world, "Error saving game.");
-    fclose(file);
+    char * err_open  = "Error saving game: "
+                       "Unable to open file 'savefile_tmp' for writing.";
+    char * err_write = "Error saving game: "
+                       "Trouble writing to opened file 'savefile_tmp'.";
+    char * err_close = "Error saving game: "
+                       "Unable to close opened file 'savefile_tmp'.";
+    char * err_unl   = "Error saving game: "
+                       "Unable to unlink old 'savefile' file.";
+    char * err_move  = "Error saving game: "
+                        "Unable to rename 'file savefile_tmp' to 'savefile'.";
+    char * savefile_tmp = "savefile_tmp";
+    char * savefile     = "savefile";
+    FILE * file = fopen(savefile_tmp, "w");
+    exit_err(0 == file, world, err_open);
+    if (   write_uint32_bigendian(world->seed, file)
+        || write_uint32_bigendian(world->turn, file)
+        || write_uint16_bigendian(world->player->pos.y + 1, file)
+        || write_uint16_bigendian(world->player->pos.x + 1, file)
+        || write_uint8(world->player->hitpoints, file)
+        || write_map_objects(world, world->monster, file)
+        || write_map_objects(world, world->item, file))
+    {
+        exit_err(1, world, err_write);
+    }
+    exit_err(fclose(file), world, err_close);
+    if (!access(savefile, F_OK))
+    {
+        exit_err(unlink(savefile), world, err_unl);
+    }
+    exit_err(rename(savefile_tmp, savefile), world, err_move);
 }