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authorGuy Harris <guy@alum.mit.edu>2020-02-04 19:53:11 -0800
committerGuy Harris <guy@alum.mit.edu>2020-02-04 19:53:11 -0800
commit52561ff05323cc5aae2bf836ecccf62c878b7690 (patch)
tree4644f3f853b645b8ba5f048e99e442018daf4913
parentaa2650ec0e9f4146a4f3c4dc9c3c58d231bbfef9 (diff)
downloadtcpdump-52561ff05323cc5aae2bf836ecccf62c878b7690.tar.gz
Push the floating-point test into a separate file.
Hopefully, that will make sure we don't optimize away anything that will, for example, cause us not to do things differently on 32-bit x86 using the x87 instructions.
-rw-r--r--CMakeLists.txt2
-rw-r--r--Makefile.in2
-rw-r--r--fptype.c50
-rw-r--r--fptype.h34
-rw-r--r--tcpdump.c11
5 files changed, 89 insertions, 10 deletions
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7fa6e900..b946c17d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1110,7 +1110,7 @@ if(NOT C_ADDITIONAL_FLAGS STREQUAL "")
set_target_properties(netdissect PROPERTIES COMPILE_FLAGS ${C_ADDITIONAL_FLAGS})
endif()
-set(TCPDUMP_SOURCE_LIST_C tcpdump.c)
+set(TCPDUMP_SOURCE_LIST_C fptype.c tcpdump.c)
if(NOT HAVE_BPF_DUMP)
set(TCPDUMP_SOURCE_LIST_C ${TCPDUMP_SOURCE_LIST_C} bpf_dump.c)
diff --git a/Makefile.in b/Makefile.in
index 694fb18b..2b3b7e3d 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -70,7 +70,7 @@ DEPENDENCY_CFLAG = @DEPENDENCY_CFLAG@
@rm -f $@
$(CC) $(FULL_CFLAGS) -c $(srcdir)/$*.c
-CSRC = tcpdump.c
+CSRC = fptype.c tcpdump.c
LIBNETDISSECT_SRC=\
addrtoname.c \
diff --git a/fptype.c b/fptype.c
new file mode 100644
index 00000000..8a209bbb
--- /dev/null
+++ b/fptype.c
@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 1982, 1986, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+
+#include "netdissect-stdinc.h"
+
+#include "fptype.h"
+
+void
+float_type_check(uint32_t in)
+{
+ union { /* int to float conversion buffer */
+ float f;
+ uint32_t i;
+ } f;
+
+ f.i = in;
+ printf("%.3f\n", f.f*8/1000000);
+}
diff --git a/fptype.h b/fptype.h
new file mode 100644
index 00000000..ad435bdd
--- /dev/null
+++ b/fptype.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 1982, 1986, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+extern void float_type_check(uint32_t);
diff --git a/tcpdump.c b/tcpdump.c
index 70cbdedf..107cdbb6 100644
--- a/tcpdump.c
+++ b/tcpdump.c
@@ -150,6 +150,8 @@ The Regents of the University of California. All rights reserved.\n";
#include "print.h"
+#include "fptype.h"
+
#ifndef PATH_MAX
#define PATH_MAX 1024
#endif
@@ -1901,14 +1903,7 @@ main(int argc, char **argv)
* may differ (e.g., it might be 32-bit, 64-bit,
* or 80-bit).
*/
- {
- union { /* int to float conversion buffer */
- float f;
- uint32_t i;
- } f;
- f.i = 0x4e93312d;
- printf("%.3f\n", f.f*8/1000000);
- }
+ float_type_check(0x4e93312d);
return 0;
default: