X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/07b5a3c3ba774ec93007827cf1233b4edb699bad..fe81b4781103a51117b904681ad2c259bf16c084:/client/reveng/bmpbit.c

diff --git a/client/reveng/bmpbit.c b/client/reveng/bmpbit.c
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+++ b/client/reveng/bmpbit.c
@@ -0,0 +1,86 @@
+/* bmpbit.c
+ * Greg Cook, 9/Apr/2015
+ */
+
+/* CRC RevEng, an arbitrary-precision CRC calculator and algorithm finder
+ * Copyright (C) 2010, 2011, 2012, 2013, 2014, 2015  Gregory Cook
+ *
+ * This file is part of CRC RevEng.
+ *
+ * CRC RevEng 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * CRC RevEng 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 CRC RevEng.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifdef BMPTST
+#  include <stdio.h>
+#  include <stdlib.h>
+#else
+#  define FILE void
+#endif
+#include "reveng.h"
+
+#if (defined BMPTST) || (BMP_BIT < 32)
+/* Size in bits of a bmp_t.  Not necessarily a power of two. */
+int bmpbit;
+
+/* The highest power of two that is strictly less than BMP_BIT.
+ * Initialises the index of a binary search for set bits in a bmp_t.
+ * (Computed correctly for BMP_BIT >= 2)
+ */
+int bmpsub;
+
+void
+setbmp(void) {
+	/* Initialise BMP_BIT and BMP_SUB for the local architecture. */
+	bmp_t bmpmax = ~(bmp_t) 0;
+
+	bmpbit = 0; bmpsub = 1;
+
+	while(bmpmax) {
+		bmpmax <<= 1;
+		++bmpbit;
+	}
+
+	while((bmpsub | (bmpsub - 1)) < bmpbit - 1)
+		bmpsub <<= 1;
+}
+#endif
+
+#ifdef BMPTST
+int
+main(int argc, char *argv[]) {
+	/* check the compile-time bitmap width is correct, otherwise
+	 * searches run forever. */
+#  if BMP_BIT > 0
+	setbmp();
+	if(BMP_BIT != bmpbit || BMP_SUB != bmpsub) {
+		fprintf(stderr,"reveng: configuration fault.  Update "
+			"config.h with these definitions and "
+			"recompile:\n"
+			"\t#define BMP_BIT   %d\n"
+			"\t#define BMP_SUB   %d\n",
+			bmpbit, bmpsub);
+		exit(EXIT_FAILURE);
+	}
+#  endif /* BMP_BIT > 0 */
+	/* check the bitmap constant macro */
+	if(~(bmp_t) 0 != ~BMP_C(0)) {
+		fprintf(stderr, "reveng: configuration fault.  Edit "
+			"the definition of BMP_C() in config.h to "
+			"match BMP_T and recompile.\n");
+		exit(EXIT_FAILURE);
+	}
+	exit(EXIT_SUCCESS);
+}
+
+#endif /* BMPTST */