[PULL 05/12] linux-user: Add strace support for a group of syscalls

[Laurent Vivier <laurent@vivier.eu>]

From: Filip Bozuta <Filip.Bozuta@syrmia.com>

This patch implements strace argument printing functionality for following syscalls:

    *acct - switch process accounting on or off

        int acct(const char *filename)
        man page: https://www.man7.org/linux/man-pages/man2/acct.2.html

    *fsync, fdatasync - synchronize a file's in-core state with storage device

        int fsync(int fd)
        int fdatasync(int fd)
        man page: https://www.man7.org/linux/man-pages/man2/fsync.2.html

    *listen - listen for connections on a socket

        int listen(int sockfd, int backlog)
        man page: https://www.man7.org/linux/man-pages/man2/listen.2.html

Implementation notes:

    Syscall acct() takes string as its only argument and thus a separate
    print function "print_acct" is stated in file "strace.list". This
    function is defined and implemented in "strace.c" by using an
    existing function used to print string arguments: "print_string()".
    All the other syscalls have only primitive argument types, so the
    rest of the implementation was handled by stating an appropriate
    printing format in file "strace.list".

Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20200619123331.17387-3-filip.bozuta@syrmia.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
---
 linux-user/strace.c    | 13 ++++++++++++-
 linux-user/strace.list |  8 ++++----
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/linux-user/strace.c b/linux-user/strace.c
index 62117e8555f6..123e022c35bf 100644
--- a/linux-user/strace.c
+++ b/linux-user/strace.c
@@ -1357,6 +1357,18 @@ print_access(const struct syscallname *name,
 }
 #endif
 
+#ifdef TARGET_NR_acct
+static void
+print_acct(const struct syscallname *name,
+    abi_long arg0, abi_long arg1, abi_long arg2,
+    abi_long arg3, abi_long arg4, abi_long arg5)
+{
+    print_syscall_prologue(name);
+    print_string(arg0, 1);
+    print_syscall_epilogue(name);
+}
+#endif
+
 #ifdef TARGET_NR_brk
 static void
 print_brk(const struct syscallname *name,
@@ -1621,7 +1633,6 @@ print_fcntl(const struct syscallname *name,
 #define print_fcntl64   print_fcntl
 #endif
 
-
 #ifdef TARGET_NR_futimesat
 static void
 print_futimesat(const struct syscallname *name,
diff --git a/linux-user/strace.list b/linux-user/strace.list
index 9281c0a75828..8a887fc16dcc 100644
--- a/linux-user/strace.list
+++ b/linux-user/strace.list
@@ -13,7 +13,7 @@
 { TARGET_NR_access, "access" , NULL, print_access, NULL },
 #endif
 #ifdef TARGET_NR_acct
-{ TARGET_NR_acct, "acct" , NULL, NULL, NULL },
+{ TARGET_NR_acct, "acct" , NULL, print_acct, NULL },
 #endif
 #ifdef TARGET_NR_add_key
 { TARGET_NR_add_key, "add_key" , NULL, NULL, NULL },
@@ -215,7 +215,7 @@
 { TARGET_NR_fcntl64, "fcntl64" , NULL, print_fcntl64, NULL },
 #endif
 #ifdef TARGET_NR_fdatasync
-{ TARGET_NR_fdatasync, "fdatasync" , NULL, NULL, NULL },
+{ TARGET_NR_fdatasync, "fdatasync" , "%s(%d)", NULL, NULL },
 #endif
 #ifdef TARGET_NR_fgetxattr
 { TARGET_NR_fgetxattr, "fgetxattr" , NULL, NULL, NULL },
@@ -251,7 +251,7 @@
 { TARGET_NR_fstatfs64, "fstatfs64" , "%s(%d,%p)", NULL, NULL },
 #endif
 #ifdef TARGET_NR_fsync
-{ TARGET_NR_fsync, "fsync" , NULL, NULL, NULL },
+{ TARGET_NR_fsync, "fsync" , "%s(%d)", NULL, NULL },
 #endif
 #ifdef TARGET_NR_ftime
 { TARGET_NR_ftime, "ftime" , NULL, NULL, NULL },
@@ -492,7 +492,7 @@
 { TARGET_NR_Linux, "Linux" , NULL, NULL, NULL },
 #endif
 #ifdef TARGET_NR_listen
-{ TARGET_NR_listen, "listen" , NULL, NULL, NULL },
+{ TARGET_NR_listen, "listen" , "%s(%d,%d)", NULL, NULL },
 #endif
 #ifdef TARGET_NR_listxattr
 { TARGET_NR_listxattr, "listxattr" , NULL, NULL, NULL },
-- 
2.26.2