Fix decoding of statfs family syscalls

Fix decoders of fstatfs, fstatfs64, statfs, and statfs64 syscalls
by rewriting them using mpers infrastructure.

* fetch_struct_statfs.c: New file.
* fstatfs.c: Likewise.
* fstatfs64.c: Likewise.
* print_statfs.c: Likewise.
* statfs.h: Likewise.
* statfs64.c: Likewise.
* statfs.c: Remove everything except SYS_FUNC(statfs).
* configure.ac: Remove the check for struct statfs64 in <sys/vfs.h>.
Add checks for struct statfs and struct statfs64 in <asm/statfs.h>.
Add checks for f_frsize and f_flags members of these structures.
* defs.h (struct strace_statfs): New forward declaration.
(print_struct_statfs, print_struct_statfs64): New prototypes.
* Makefile.am (libstrace_a_SOURCES): Add fstatfs.c, fstatfs64.c,
statfs.c, and statfs64.c.
(strace_SOURCES): Add fetch_struct_statfs.c, print_statfs.c,
and statfs.h.
* NEWS: Mention this fix.
* tests/fstatfs.c: New file.
* tests/fstatfs64.c: Likewise.
* tests/statfs64.c: Likewise.
* tests/xstatfs.c: Likewise.
* tests/xstatfs64.c: Likewise.
* tests/xstatfsx.c: Likewise.
* tests/fstatfs.test: New test.
* tests/fstatfs64.test: Likewise.
* tests/statfs64.test: Likewise.
* tests/statfs.c: Rewrite using xstatfs.c.
* tests/statfs.test: Update.
* tests/.gitignore: Add fstatfs, fstatfs64, and statfs64.
* tests/Makefile.am (check_PROGRAMS): Likewise.
(DECODER_TESTS): Add  fstatfs.test, fstatfs64.test, and statfs64.test.
(EXTRA_DIST): Add xstatfs.c, xstatfs64.c, and xstatfsx.c.
diff --git a/print_statfs.c b/print_statfs.c
new file mode 100644
index 0000000..17f4c6f
--- /dev/null
+++ b/print_statfs.c
@@ -0,0 +1,128 @@
+/*
+ * Copyright (c) 2014-2016 Dmitry V. Levin <ldv@altlinux.org>
+ * 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. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 "defs.h"
+#include "statfs.h"
+#include "xlat/fsmagic.h"
+#include "xlat/statfs_flags.h"
+
+static void
+print_statfs_type(const char *const prefix, const unsigned long long magic)
+{
+	tprints(prefix);
+	const char *s = xlat_search(fsmagic, ARRAY_SIZE(fsmagic), magic);
+	if (s)
+		tprints(s);
+	else
+		tprintf("%#llx", magic);
+}
+
+static void
+print_statfs_flags(const char *const prefix, const unsigned long long flags)
+{
+	if (flags & ST_VALID) {
+		tprints(prefix);
+		printflags(statfs_flags, flags, "ST_???");
+	}
+}
+
+static void
+print_statfs_number(const char *const prefix, const unsigned long long number)
+{
+	tprints(prefix);
+	tprintf("%llu",  number);
+}
+
+void
+print_struct_statfs(struct tcb *tcp, const long addr)
+{
+#ifdef HAVE_STRUCT_STATFS
+	struct strace_statfs b;
+
+	if (!fetch_struct_statfs(tcp, addr, &b))
+		return;
+
+	print_statfs_type("{f_type=", b.f_type);
+	print_statfs_number(", f_bsize=", b.f_bsize);
+	print_statfs_number(", f_blocks=", b.f_blocks);
+	print_statfs_number(", f_bfree=", b.f_bfree);
+	print_statfs_number(", f_bavail=", b.f_bavail);
+	print_statfs_number(", f_files=", b.f_files);
+	print_statfs_number(", f_ffree=", b.f_ffree);
+# if defined HAVE_STRUCT_STATFS_F_FSID_VAL \
+  || defined HAVE_STRUCT_STATFS_F_FSID___VAL
+	print_statfs_number(", f_fsid={", b.f_fsid[0]);
+	print_statfs_number(", ", b.f_fsid[1]);
+	tprints("}");
+# endif
+	print_statfs_number(", f_namelen=", b.f_namelen);
+# ifdef HAVE_STRUCT_STATFS_F_FRSIZE
+	print_statfs_number(", f_frsize=", b.f_frsize);
+# endif
+# ifdef HAVE_STRUCT_STATFS_F_FLAGS
+	print_statfs_flags(", f_flags=", b.f_flags);
+# endif
+	tprints("}");
+#else
+	printaddr(addr);
+#endif
+}
+
+void
+print_struct_statfs64(struct tcb *tcp, const long addr, const unsigned long size)
+{
+#ifdef HAVE_STRUCT_STATFS64
+	struct strace_statfs b;
+
+	if (!fetch_struct_statfs64(tcp, addr, size, &b))
+		return;
+
+	print_statfs_type("{f_type=", b.f_type);
+	print_statfs_number(", f_bsize=", b.f_bsize);
+	print_statfs_number(", f_blocks=", b.f_blocks);
+	print_statfs_number(", f_bfree=", b.f_bfree);
+	print_statfs_number(", f_bavail=", b.f_bavail);
+	print_statfs_number(", f_files=", b.f_files);
+	print_statfs_number(", f_ffree=", b.f_ffree);
+# if defined HAVE_STRUCT_STATFS64_F_FSID_VAL \
+  || defined HAVE_STRUCT_STATFS64_F_FSID___VAL
+	print_statfs_number(", f_fsid={", b.f_fsid[0]);
+	print_statfs_number(", ", b.f_fsid[1]);
+	tprints("}");
+# endif
+	print_statfs_number(", f_namelen=", b.f_namelen);
+# ifdef HAVE_STRUCT_STATFS64_F_FRSIZE
+	print_statfs_number(", f_frsize=", b.f_frsize);
+# endif
+# ifdef HAVE_STRUCT_STATFS64_F_FLAGS
+	print_statfs_flags(", f_flags=", b.f_flags);
+# endif
+	tprints("}");
+#else
+	printaddr(addr);
+#endif
+}