inotify: decode file descriptor returned by inotify_init

* inotify.c (SYS_FUNC(inotify_init)): New function.
* linux/dummy.h (sys_inotify_init): Remove macro definition.
* tests/.gitignore: Add inotify_init, inotify_init-y, inotify_init1-y.
* tests/pure_executables.list: Likewise.
* tests/gen_tests.in (inotify_init, inotify_init-y, inotify_init1-y):
New tests.
* tests/inotify_init-y.c: New file.
* tests/inotify_init.c: Likewise.
* tests/inotify_init1-y.c: Likewise.
* tests/inotify_init1.c [PRINT_PATHS]: Print inotify fd path.

inotify.c

@@ -56,6 +56,11 @@ SYS_FUNC(inotify_rm_watch)
 	return RVAL_DECODED;
 }
 
+SYS_FUNC(inotify_init)
+{
+	return RVAL_DECODED | RVAL_FD;
+}
+
 SYS_FUNC(inotify_init1)
 {
 	printflags(inotify_init_flags, tcp->u_arg[0], "IN_???");

linux/dummy.h

@@ -110,7 +110,6 @@
 #define	sys_getppid		printargs
 #define	sys_gettid		printargs
 #define	sys_idle		printargs
-#define	sys_inotify_init	printargs
 #define	sys_munlockall		printargs
 #define	sys_pause		printargs
 #define	sys_printargs		printargs

tests/.gitignore

@@ -135,7 +135,10 @@ inet-cmsg
 init_module
 inject-nf
 inotify
+inotify_init
+inotify_init-y
 inotify_init1
+inotify_init1-y
 int_0x80
 ioctl
 ioctl_block

tests/gen_tests.in

@@ -131,7 +131,10 @@ group_req	-e trace=setsockopt
 inet-cmsg	-e trace=recvmsg
 init_module	-a27
 inotify	-a23 -e trace=inotify_add_watch,inotify_rm_watch
+inotify_init	-a15
+inotify_init-y	-a15 -y -e trace=inotify_init
 inotify_init1	-a27
+inotify_init1-y	-a27 -y -e trace=inotify_init1
 int_0x80	-a11 -e trace=getgid32
 ioctl_block	+ioctl.test
 ioctl_dm	+ioctl.test -s9

tests/inotify_init-y.c

@@ -0,0 +1,2 @@
+#define PRINT_PATHS
+#include "inotify_init.c"

tests/inotify_init.c

@@ -0,0 +1,68 @@
+/*
+ * Check decoding of inotify_init syscall.
+ *
+ * Copyright (c) 2018 The strace developers.
+ * 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 <asm/unistd.h>
+
+#if defined(__NR_inotify_init)
+
+# include <stdio.h>
+# include <unistd.h>
+
+int
+main(void)
+{
+	long rc;
+
+	rc = syscall(__NR_inotify_init, 42);
+
+#ifdef PRINT_PATHS
+	if (rc < 0)
+		perror_msg_and_skip("inotify_init");
+#endif
+
+	printf("inotify_init() = "
+#ifdef PRINT_PATHS
+	       "%ld<anon_inode:inotify>\n", rc
+#else
+	       "%s\n", sprintrc(rc)
+#endif
+	       );
+
+	puts("+++ exited with 0 +++");
+
+	return 0;
+}
+
+#else
+
+SKIP_MAIN_UNDEFINED("__NR_inotify_init");
+
+#endif

tests/inotify_init1-y.c

@@ -0,0 +1,2 @@
+#define PRINT_PATHS
+#include "inotify_init1.c"

tests/inotify_init1.c

@@ -44,6 +44,12 @@
 # endif
 # define all_flags (O_NONBLOCK | cloexec_flag)
 
+#ifdef PRINT_PATHS
+# define RC_FMT "%ld<anon_inode:inotify>"
+#else
+# define RC_FMT "%s"
+#endif
+
 int
 main(void)
 {
@@ -65,8 +71,18 @@ main(void)
 	       (unsigned int) bogus_flags2, sprintrc(rc));
 
 	rc = syscall(__NR_inotify_init1, all_flags);
-	printf("inotify_init1(IN_NONBLOCK%s) = %s\n",
-	       all_flags & cloexec_flag ? "|IN_CLOEXEC" : "", sprintrc(rc));
+#ifdef PRINT_PATHS
+	if (rc < 0)
+		perror_msg_and_skip("inotify_init(%#x)", all_flags);
+#endif
+	printf("inotify_init1(IN_NONBLOCK%s) = " RC_FMT "\n",
+	       all_flags & cloexec_flag ? "|IN_CLOEXEC" : "",
+#ifdef PRINT_PATHS
+	       rc
+#else
+	       sprintrc(rc)
+#endif
+	       );
 
 	puts("+++ exited with 0 +++");
 

tests/pure_executables.list

@@ -107,7 +107,10 @@ group_req
 inet-cmsg
 init_module
 inotify
+inotify_init
+inotify_init-y
 inotify_init1
+inotify_init1-y
 ioctl
 ioctl_block
 ioctl_dm