Convert parsers of flock structures to new mpers infrastructure

* fetch_struct_flock.c: New file.
* Makefile.am (strace_SOURCES): Add it.
* fcntl.c (print_struct_flock64): New function.
(printflock64): Use fetch_struct_flock64 and print_struct_flock64.
(printflock): Use fetch_struct_flock and print_struct_flock64.

Author: ldv-alt

Makefile.am

@@ -62,6 +62,7 @@ strace_SOURCES =	\
 	fchownat.c	\
 	fcntl.c		\
 	fetch_seccomp_fprog.c \
+	fetch_struct_flock.c \
 	file.c		\
 	file_handle.c	\
 	flock.c		\

fcntl.c

@@ -39,73 +39,35 @@
 #include "xlat/notifyflags.h"
 
 static void
-printflock64(struct tcb *tcp, long addr, int getlk)
+print_struct_flock64(const struct_kernel_flock64 *fl, const int getlk)
+{
+	tprints("{l_type=");
+	printxval(lockfcmds, fl->l_type, "F_???");
+	tprints(", l_whence=");
+	printxval(whence_codes, fl->l_whence, "SEEK_???");
+	tprintf(", l_start=%Ld, l_len=%Ld",
+		(long long) fl->l_start, (long long) fl->l_len);
+	if (getlk)
+		tprintf(", l_pid=%lu", (unsigned long) fl->l_pid);
+	tprints("}");
+}
+
+static void
+printflock64(struct tcb *tcp, const long addr, const int getlk)
 {
 	struct_kernel_flock64 fl;
 
-	if (umove_or_printaddr(tcp, addr, &fl))
-		return;
-	tprints("{type=");
-	printxval(lockfcmds, fl.l_type, "F_???");
-	tprints(", whence=");
-	printxval(whence_codes, fl.l_whence, "SEEK_???");
-	tprintf(", start=%lld, len=%lld", (long long) fl.l_start, (long long) fl.l_len);
-	if (getlk)
-		tprintf(", pid=%lu}", (unsigned long) fl.l_pid);
-	else
-		tprints("}");
+	if (fetch_struct_flock64(tcp, addr, &fl))
+		print_struct_flock64(&fl, getlk);
 }
 
 static void
-printflock(struct tcb *tcp, long addr, int getlk)
+printflock(struct tcb *tcp, const long addr, const int getlk)
 {
-	struct_kernel_flock fl;
+	struct_kernel_flock64 fl;
 
-#if SUPPORTED_PERSONALITIES > 1
-	if (
-# if SIZEOF_OFF_T > SIZEOF_LONG
-	    current_personality != DEFAULT_PERSONALITY &&
-# endif
-	    current_wordsize != sizeof(fl.l_start)) {
-		if (current_wordsize == 4) {
-			/* 32-bit x86 app on x86_64 and similar cases */
-			struct {
-				short int l_type;
-				short int l_whence;
-				int32_t l_start; /* off_t */
-				int32_t l_len; /* off_t */
-				int32_t l_pid; /* pid_t */
-			} fl32;
-			if (umove_or_printaddr(tcp, addr, &fl32))
-				return;
-			fl.l_type = fl32.l_type;
-			fl.l_whence = fl32.l_whence;
-			fl.l_start = fl32.l_start;
-			fl.l_len = fl32.l_len;
-			fl.l_pid = fl32.l_pid;
-		} else {
-			/* let people know we have a problem here */
-			tprintf("<decode error: unsupported wordsize %d>",
-				current_wordsize);
-			return;
-		}
-	} else
-#endif
-	if (umove_or_printaddr(tcp, addr, &fl))
-		return;
-	tprints("{type=");
-	printxval(lockfcmds, fl.l_type, "F_???");
-	tprints(", whence=");
-	printxval(whence_codes, fl.l_whence, "SEEK_???");
-#if SIZEOF_OFF_T > SIZEOF_LONG
-	tprintf(", start=%lld, len=%lld", fl.l_start, fl.l_len);
-#else
-	tprintf(", start=%ld, len=%ld", fl.l_start, fl.l_len);
-#endif
-	if (getlk)
-		tprintf(", pid=%lu}", (unsigned long) fl.l_pid);
-	else
-		tprints("}");
+	if (fetch_struct_flock(tcp, addr, &fl))
+		print_struct_flock64(&fl, getlk);
 }
 
 static void

fetch_struct_flock.c

@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2015 Dmitry V. Levin <[email protected]>
+ * 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 DEF_MPERS_TYPE(struct_flock)
+#include DEF_MPERS_TYPE(struct_flock64)
+
+#include "flock.h"
+typedef struct_kernel_flock struct_flock;
+typedef struct_kernel_flock64 struct_flock64;
+
+#include MPERS_DEFS
+
+#define SIZEOF_MEMBER(type, member) \
+	sizeof(((type *) NULL)->member)
+
+#define FLOCK_MEMBERS_EQ(type, member) \
+	(SIZEOF_MEMBER(struct_kernel_flock64, member) == SIZEOF_MEMBER(type, member) \
+	 && offsetof(struct_kernel_flock64, member) == offsetof(type, member))
+
+#define FLOCK_STRUCTS_EQ(type) \
+	(sizeof(struct_kernel_flock64) == sizeof(type) \
+	 && FLOCK_MEMBERS_EQ(type, l_type) \
+	 && FLOCK_MEMBERS_EQ(type, l_whence) \
+	 && FLOCK_MEMBERS_EQ(type, l_start) \
+	 && FLOCK_MEMBERS_EQ(type, l_len) \
+	 && FLOCK_MEMBERS_EQ(type, l_pid))
+
+MPERS_PRINTER_DECL(bool, fetch_struct_flock)(struct tcb *tcp, const long addr, void *p)
+{
+	struct_kernel_flock64 *pfl = p;
+	struct_flock mfl;
+
+	if (FLOCK_STRUCTS_EQ(struct_flock))
+		return !umove_or_printaddr(tcp, addr, pfl);
+
+	if (umove_or_printaddr(tcp, addr, &mfl))
+		return false;
+
+	pfl->l_type = mfl.l_type;
+	pfl->l_whence = mfl.l_whence;
+	pfl->l_start = mfl.l_start;
+	pfl->l_len = mfl.l_len;
+	pfl->l_pid = mfl.l_pid;
+	return true;
+}
+
+MPERS_PRINTER_DECL(bool, fetch_struct_flock64)(struct tcb *tcp, const long addr, void *p)
+{
+	struct_kernel_flock64 *pfl = p;
+	struct_flock64 mfl;
+
+	if (FLOCK_STRUCTS_EQ(struct_flock64))
+		return !umove_or_printaddr(tcp, addr, pfl);
+
+	if (umove_or_printaddr(tcp, addr, &mfl))
+		return false;
+
+	pfl->l_type = mfl.l_type;
+	pfl->l_whence = mfl.l_whence;
+	pfl->l_start = mfl.l_start;
+	pfl->l_len = mfl.l_len;
+	pfl->l_pid = mfl.l_pid;
+	return true;
+}