X-Git-Url: http://git.xonotic.org/?p=xonotic%2Fdarkplaces.git;a=blobdiff_plain;f=qdefs.h;h=5d0655f77f6e0b519bab330b08678166e20e639f;hp=1996d86fbcb6bad629ede75c4b4e9674c4f6a01d;hb=fe6c374412a5d42d5cd84945d8101c4a398e96d5;hpb=20a31a160b9dbb9788b943d3284a26c873a62c3b

diff --git a/qdefs.h b/qdefs.h
index 1996d86f..5d0655f7 100644
--- a/qdefs.h
+++ b/qdefs.h
@@ -1,6 +1,10 @@
 #ifndef QDEFS_H
 #define QDEFS_H
 
+#if defined (__GNUC__) || defined (__clang__) || defined (__TINYC__)
+#define DP_GCC_COMPATIBLE
+#endif
+
 #if (__GNUC__ > 2) || defined (__clang__) || (__TINYC__)
 #define DP_FUNC_PRINTF(n) __attribute__ ((format (printf, n, n+1)))
 #define DP_FUNC_PURE      __attribute__ ((pure))
@@ -11,6 +15,12 @@
 #define DP_FUNC_NORETURN
 #endif
 
+#ifdef DP_GCC_COMPATIBLE
+#define Q_typeof(var) typeof(var)
+#elif defined (MSVC)
+#define Q_typeof(var) decltype(var)
+#endif
+
 #define MAX_NUM_ARGVS	50
 
 #ifdef DP_SMALLMEMORY
@@ -90,7 +100,7 @@
 #define	CMDBUFSIZE				655360 ///< maximum script size that can be loaded by the exec command (8192 in Quake)
 #define	MAX_ARGS				80 ///< maximum number of parameters to a console command or alias
 
-#define	NET_MAXMESSAGE			131072 ///< max reliable packet size (sent as multiple fragments of MAX_PACKETFRAGMENT)
+#define	NET_MAXMESSAGE			65536 ///< max reliable packet size (sent as multiple fragments of MAX_PACKETFRAGMENT)
 #define	MAX_PACKETFRAGMENT		1024 ///< max length of packet fragment
 #define	MAX_EDICTS				32768 ///< max number of objects in game world at once (32768 protocol limit)
 #define	MAX_MODELS				8192 ///< max number of models loaded at once (including during level transitions)
@@ -198,4 +208,22 @@
 #define INT_LOSSLESS_FORMAT_CONVERT_U(x) ((uintmax_t)(x))
 #endif
 
+// simple safe library to handle integer overflows when doing buffer size calculations
+// Usage:
+//   - calculate data size using INTOVERFLOW_??? macros
+//   - compare: calculated-size <= INTOVERFLOW_NORMALIZE(buffersize)
+// Functionality:
+//   - all overflows (values > INTOVERFLOW_MAX) and errors are mapped to INTOVERFLOW_MAX
+//   - if any input of an operation is INTOVERFLOW_MAX, INTOVERFLOW_MAX will be returned
+//   - otherwise, regular arithmetics apply
+
+#define INTOVERFLOW_MAX 2147483647
+
+#define INTOVERFLOW_ADD(a,b) (((a) < INTOVERFLOW_MAX && (b) < INTOVERFLOW_MAX && (a) < INTOVERFLOW_MAX - (b)) ? ((a) + (b)) : INTOVERFLOW_MAX)
+#define INTOVERFLOW_SUB(a,b) (((a) < INTOVERFLOW_MAX && (b) < INTOVERFLOW_MAX && (b) <= (a))                  ? ((a) - (b)) : INTOVERFLOW_MAX)
+#define INTOVERFLOW_MUL(a,b) (((a) < INTOVERFLOW_MAX && (b) < INTOVERFLOW_MAX && (a) < INTOVERFLOW_MAX / (b)) ? ((a) * (b)) : INTOVERFLOW_MAX)
+#define INTOVERFLOW_DIV(a,b) (((a) < INTOVERFLOW_MAX && (b) < INTOVERFLOW_MAX && (b) > 0)                     ? ((a) / (b)) : INTOVERFLOW_MAX)
+
+#define INTOVERFLOW_NORMALIZE(a) (((a) < INTOVERFLOW_MAX) ? (a) : (INTOVERFLOW_MAX - 1))
+
 #endif