From: Eric S. Raymond <esr@thyrsus.com>
Date: Thu, 6 Apr 2023 23:03:02 +0000 (-0400)
Subject: Implement the magic-cookie check and its test.
X-Git-Tag: 1.16~29
X-Git-Url: https://jxself.org/git/?a=commitdiff_plain;h=58cf204eba055cc7633aa83be7ec6f7c06ed70b7;p=open-adventure.git

Implement the magic-cookie check and its test.
---

diff --git a/adventure.yaml b/adventure.yaml
index a48ee7d..8909914 100644
--- a/adventure.yaml
+++ b/adventure.yaml
@@ -3186,6 +3186,7 @@ arbitrary_messages:  !!omap
 #    %d of %d "random" messages   %d of %d "class" messages
 #    %d of %d hints               %d of %d turn thresholds'
 - RESUME_ABANDON: 'To resume an earlier Adventure, you must abandon the current one.'
+- BAD_SAVE: 'Oops, that does not look like a valid save file.'
 - VERSION_SKEW: |-
     I'm sorry, but that Adventure was begun using Version %d.%d of the
     save file format, and this program uses Version %d.%d.  You must find an instance
diff --git a/saveresume.c b/saveresume.c
index 76de1c4..0ed8cd3 100644
--- a/saveresume.c
+++ b/saveresume.c
@@ -135,7 +135,9 @@ int restore(FILE* fp)
 
     IGNORE(fread(&save, sizeof(struct save_t), 1, fp));
     fclose(fp);
-    if (save.version != SAVE_VERSION) {
+    if (memcmp(save.magic, ADVENT_MAGIC, sizeof(ADVENT_MAGIC)) != 0)
+	rspeak(BAD_SAVE);
+    else if (save.version != SAVE_VERSION) {
         rspeak(VERSION_SKEW, save.version / 10, MOD(save.version, 10), SAVE_VERSION / 10, MOD(SAVE_VERSION, 10));
     } else if (!is_valid(save.game)) {
 	rspeak(SAVE_TAMPERING);
diff --git a/tests/badmagic.chk b/tests/badmagic.chk
new file mode 100644
index 0000000..08c8ffe
--- /dev/null
+++ b/tests/badmagic.chk
@@ -0,0 +1,22 @@
+
+Welcome to Adventure!!  Would you like instructions?
+
+> n
+
+You are standing at the end of a road before a small brick building.
+Around you is a forest.  A small stream flows out of the building and
+down a gully.
+
+> resume
+Can't open file y, try again.
+
+Oops, that does not look like a valid save file.
+
+You're in front of building.
+
+> 
+You scored 32 out of a possible 430, using 1 turn.
+
+You are obviously a rank amateur.  Better luck next time.
+
+To achieve the next higher rating, you need 14 more points.
diff --git a/tests/badmagic.log b/tests/badmagic.log
new file mode 100644
index 0000000..4ee9f10
--- /dev/null
+++ b/tests/badmagic.log
@@ -0,0 +1,8 @@
+## Resume from filename withoy the right magic at the front 
+# SPDX-FileCopyrightText: Eric S. Raymond <esr@thyrsus.com>
+# SPDX-License-Identifier: BSD-2-Clause
+#NOCOMPARE advent430 doesn't have this test
+n
+resume
+y
+../main.o