Implement dumping of vmsplice syscall

* syscall.c (dumpio): Add SEN_vmsplice.
* NEWS: Mention this.
* tests/vmsplice.c: New file.
* tests/vmsplice.test: New test.
* tests/.gitignore: Add vmsplice.
* tests/Makefile.am (check_PROGRAMS): Likewise.
(TESTS): Add vmsplice.test.

NEWS

@@ -11,6 +11,7 @@ Noteworthy changes in release ?.?? (????-??-??)
   * Implemented caching of netlink conversations to reduce amount of time
     spent in decoding socket details in -yy mode.
   * Implemented decoding of copy_file_range syscall.
+  * Implemented dumping of vmsplice syscall.
 
 * Bug fixes
   * Fixed build on arc, metag, nios2, or1k, and tile architectures.

syscall.c

@@ -707,6 +707,7 @@ dumpio(struct tcb *tcp)
 			dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
 			break;
 		case SEN_writev:
+		case SEN_vmsplice:
 			dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
 			break;
 		case SEN_sendmsg:

tests/.gitignore

@@ -121,6 +121,7 @@ userfaultfd
 utime
 utimensat
 vfork-f
+vmsplice
 wait
 xattr
 xet_robust_list

tests/Makefile.am

@@ -169,6 +169,7 @@ check_PROGRAMS = \
 	utime \
 	utimensat \
 	vfork-f \
+	vmsplice \
 	wait \
 	xattr \
 	xet_robust_list \
@@ -312,6 +313,7 @@ TESTS = \
 	utime.test \
 	utimensat.test \
 	vfork-f.test \
+	vmsplice.test \
 	wait.test \
 	xattr.test \
 	xet_robust_list.test \

tests/vmsplice.c

@@ -0,0 +1,106 @@
+/*
+ * This file is part of vmsplice strace test.
+ *
+ * Copyright (c) 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 "tests.h"
+#include <sys/syscall.h>
+
+#if defined __NR_vmsplice
+
+# include <assert.h>
+# include <stdio.h>
+# include <unistd.h>
+# include <sys/uio.h>
+
+int
+main(void)
+{
+	tprintf("%s", "");
+
+	int fds[2];
+	if (pipe(fds))
+		perror_msg_and_fail("pipe");
+	assert(0 == fds[0]);
+	assert(1 == fds[1]);
+
+	static const char w0_c[] = "012";
+	const char *w0_d = hexdump_strdup(w0_c);
+	void *w0 = tail_memdup(w0_c, LENGTH_OF(w0_c));
+
+	static const char w1_c[] = "34567";
+	const char *w1_d = hexdump_strdup(w1_c);
+	void *w1 = tail_memdup(w1_c, LENGTH_OF(w1_c));
+
+	static const char w2_c[] = "89abcde";
+	const char *w2_d = hexdump_strdup(w2_c);
+	void *w2 = tail_memdup(w2_c, LENGTH_OF(w2_c));
+
+	const struct iovec iov_[] = {
+		{
+			.iov_base = w0,
+			.iov_len = LENGTH_OF(w0_c)
+		}, {
+			.iov_base = w1,
+			.iov_len = LENGTH_OF(w1_c)
+		}, {
+			.iov_base = w2,
+			.iov_len = LENGTH_OF(w2_c)
+		}
+	};
+	const struct iovec *iov = tail_memdup(iov_, sizeof(iov_));
+	const unsigned int len =
+		LENGTH_OF(w0_c) + LENGTH_OF(w1_c) + LENGTH_OF(w2_c);
+
+	tprintf("vmsplice(1, [{\"%s\", %u}, {\"%s\", %u}"
+		", {\"%s\", %u}], %u, %s) = %u\n"
+		" * %u bytes in buffer 0\n"
+		" | 00000 %-49s  %-16s |\n"
+		" * %u bytes in buffer 1\n"
+		" | 00000 %-49s  %-16s |\n"
+		" * %u bytes in buffer 2\n"
+		" | 00000 %-49s  %-16s |\n",
+		w0_c, LENGTH_OF(w0_c), w1_c, LENGTH_OF(w1_c),
+		w2_c, LENGTH_OF(w2_c), ARRAY_SIZE(iov_),
+		"SPLICE_F_NONBLOCK", len,
+		LENGTH_OF(w0_c), w0_d, w0_c,
+		LENGTH_OF(w1_c), w1_d, w1_c, LENGTH_OF(w2_c), w2_d, w2_c);
+
+	const long rc = syscall(__NR_vmsplice, 1, iov, ARRAY_SIZE(iov_), 2);
+	if (rc < 0)
+		perror_msg_and_skip("vmsplice");
+	assert(rc == (int) len);
+
+	tprintf("+++ exited with 0 +++\n");
+	return 0;
+}
+
+#else
+
+SKIP_MAIN_UNDEFINED("__NR_vmsplice")
+
+#endif

tests/vmsplice.test

@@ -0,0 +1,11 @@
+#!/bin/sh
+
+# Check decoding of vmsplice syscall.
+
+. "${srcdir=.}/init.sh"
+
+run_prog > /dev/null
+OUT="$LOG.out"
+run_strace -ewrite=1 -evmsplice $args > "$OUT"
+match_diff "$LOG" "$OUT"
+rm -f "$OUT"