X-Git-Url: https://git.draconx.ca/gitweb/upkg.git/blobdiff_plain/959d4dd5bc102359f414a7feb718d56bf1b012e6..5aaf7aaa7d95bb26178ae2c192b84401f5544244:/src/pack.c

diff --git a/src/pack.c b/src/pack.c
index b87ac34..38a4f44 100644
--- a/src/pack.c
+++ b/src/pack.c
@@ -1,28 +1,16 @@
 /*
- *  upkg: tool for manipulating Unreal Tournament packages.
- *  Copyright (C) 2009 Nick Bowler
+ *  Portable binary serialisation of integral types.
+ *  Copyright © 2009 Nick Bowler
  *
- *  This program 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; either version 2 of the License, or
- *  (at your option) any later version.
- *
- *  This program 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 this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  Copying and distribution of this file, with or without modification,
+ *  are permitted in any medium without royalty provided the copyright
+ *  notice and this notice are preserved.  This file is offered as-is,
+ *  without any warranty.
  */
 
-#include <stdio.h>
-#include <limits.h>
-
 #include "pack.h"
 
-/* Integer packing. */
+/* Unsigned integer packing. */
 #define DEFPACK_BE(bits, type) void pack_ ## bits ## _be ( \
 	unsigned char *out, type v \
 ) { \
@@ -45,18 +33,18 @@
 
 DEFPACK_BE(16, unsigned short)
 DEFPACK_BE(32, unsigned long)
-#ifdef ULLONG_MAX
+#if PACK_HAVE_64BIT
 DEFPACK_BE(64, unsigned long long)
 #endif
 
 DEFPACK_LE(16, unsigned short)
 DEFPACK_LE(32, unsigned long)
-#ifdef ULLONG_MAX
+#if PACK_HAVE_64BIT
 DEFPACK_LE(64, unsigned long long)
 #endif
 
 #define DEFUNPACK_BE(bits, type) type unpack_ ## bits ## _be ( \
-	unsigned char *in \
+	const unsigned char *in \
 ) { \
 	type v = 0; \
 	unsigned i; \
@@ -68,7 +56,7 @@ DEFPACK_LE(64, unsigned long long)
 }
 
 #define DEFUNPACK_LE(bits, type) type unpack_ ## bits ## _le ( \
-	unsigned char *in \
+	const unsigned char *in \
 ) { \
 	type v = 0; \
 	unsigned i; \
@@ -81,12 +69,55 @@ DEFPACK_LE(64, unsigned long long)
 
 DEFUNPACK_BE(16, unsigned short)
 DEFUNPACK_BE(32, unsigned long)
-#ifdef ULLONG_MAX
+#if PACK_HAVE_64BIT
 DEFUNPACK_BE(64, unsigned long long)
 #endif
 
 DEFUNPACK_LE(16, unsigned short)
 DEFUNPACK_LE(32, unsigned long)
-#ifdef ULLONG_MAX
+#if PACK_HAVE_64BIT
 DEFUNPACK_LE(64, unsigned long long)
 #endif
+
+/*
+ * Two's complement signed integer packing.  This is unlikely to work on
+ * systems that don't themselves use two's complement.
+ */
+
+#define DEFUNPACK_SBE(bits, max, type) type unpack_s ## bits ## _be ( \
+	const unsigned char *in \
+) { \
+	type v = 0; \
+	unsigned i; \
+	int sign = (in[0] & 0x80) ? 1 : 0; \
+	for (i = 0; i < bits/8; i++) { \
+		v *= 256; \
+		v += in[i] & (i == 0 ? 0x7f : 0xff); \
+	} \
+	return sign*(-max-1) + v; \
+}
+
+#define DEFUNPACK_SLE(bits, max, type) type unpack_s ## bits ## _le ( \
+	const unsigned char *in \
+) { \
+	type v = 0; \
+	unsigned i; \
+	int sign = (in[bits/8 - 1] & 0x80) ? 1 : 0; \
+	for (i = 1; i <= bits/8; i++) { \
+		v *= 256; \
+		v += in[bits/8 - i] & (i == 1 ? 0x7f : 0xff); \
+	} \
+	return sign*(-max-1) + v; \
+}
+
+DEFUNPACK_SBE(16, 32767, short)
+DEFUNPACK_SBE(32, 2147483647l, long)
+#if PACK_HAVE_64BIT
+DEFUNPACK_SBE(64, 9223372036854775807ll, long long)
+#endif
+
+DEFUNPACK_SLE(16, 32767, short)
+DEFUNPACK_SLE(32, 2147483647l, long)
+#if PACK_HAVE_64BIT
+DEFUNPACK_SLE(64, 9223372036854775807ll, long long)
+#endif