(svn r26482) -Codechange: add an include that allows us to undefine/redefine "unsafe" functions to prevent them from being used, and thus having to care about certain aspects of their return values

1 files changed, 67 insertions, 0 deletions

diff --git a/src/safeguards.h b/src/safeguards.h
new file mode 100644
index 000000000..e4c8949f1
--- /dev/null
+++ b/src/safeguards.h
@@ -0,0 +1,67 @@
+/* $Id$ */
+
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
+ * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * @file safeguards.h A number of safeguards to prevent using unsafe methods.
+ *
+ * Unsafe methods are, for example, strndup and strncpy because they may leave the
+ * string without a null termination, but also strdup and strndup because they can
+ * return NULL and then all strdups would need to be guarded against that instead
+ * of using the current MallocT/ReallocT/CallocT technique of just giving the user
+ * an error that too much memory was used instead of spreading that code though
+ * the whole code base.
+ */
+
+#ifndef SAFEGUARDS_H
+#define SAFEGUARDS_H
+
+/* Use MallocT instead. */
+#define malloc    SAFEGUARD_DO_NOT_USE_THIS_METHOD
+
+/* Use MallocT instead. */
+#define calloc    SAFEGUARD_DO_NOT_USE_THIS_METHOD
+
+/* Use ReallocT instead. */
+#define realloc   SAFEGUARD_DO_NOT_USE_THIS_METHOD
+
+/* Use stredup instead. */
+//#define strdup    SAFEGUARD_DO_NOT_USE_THIS_METHOD
+
+/* Use stredup instead. */
+//#define strndup   SAFEGUARD_DO_NOT_USE_THIS_METHOD
+
+/* Use strecpy instead. */
+//#define strcpy    SAFEGUARD_DO_NOT_USE_THIS_METHOD
+//#define strncpy   SAFEGUARD_DO_NOT_USE_THIS_METHOD
+
+/* Use strecat instead. */
+//#define strcat    SAFEGUARD_DO_NOT_USE_THIS_METHOD
+//#define strncat   SAFEGUARD_DO_NOT_USE_THIS_METHOD
+
+/* Use seprintf instead. */
+//#define sprintf   SAFEGUARD_DO_NOT_USE_THIS_METHOD
+//#define snprintf  SAFEGUARD_DO_NOT_USE_THIS_METHOD
+
+/* Use vseprintf instead. */
+//#define vsprintf  SAFEGUARD_DO_NOT_USE_THIS_METHOD
+//#define vsnprintf SAFEGUARD_DO_NOT_USE_THIS_METHOD
+
+/* Use fgets instead. */
+#define gets      SAFEGUARD_DO_NOT_USE_THIS_METHOD
+
+/* No clear replacement. */
+//#define strtok    SAFEGUARD_DO_NOT_USE_THIS_METHOD
+
+/*
+ * Possible future methods to mark unsafe, though needs more thought:
+ *  - memcpy; when memory area overlaps it messes up, use memmove.
+ *  - strlen: when the data is 'garbage', this could read beyond bounds.
+ */
+
+#endif /* SAFEGUARDS_H */