Re: [PATCH v5 3/6] linux-user: Add strace support for printing argument of syscalls used for extended attributes

[Laurent Vivier]

Le 19/06/2020 à 14:33, Filip Bozuta a écrit :
> From: Filip Bozuta <Filip.Bozuta@syrmia.com>
> 
> This patch implements strace argument printing functionality for following 
> syscalls:
> 
>     *getxattr, lgetxattr, fgetxattr - retrieve an extended attribute value
> 
>         ssize_t getxattr(const char *path, const char *name, void *value, 
> size_t size)
>         ssize_t lgetxattr(const char *path, const char *name, void *value, 
> size_t size)
>         ssize_t fgetxattr(int fd, const char *name, void *value, size_t size)
>         man page: https://www.man7.org/linux/man-pages/man2/getxattr.2.html
> 
>     *listxattr, llistxattr, flistxattr - list extended attribute names
> 
>         ssize_t listxattr(const char *path, char *list, size_t size)
>         ssize_t llistxattr(const char *path, char *list, size_t size)
>         ssize_t flistxattr(int fd, char *list, size_t size)
>         man page: https://www.man7.org/linux/man-pages/man2/listxattr.2.html
> 
>     *removexattr, lremovexattr, fremovexattr - remove an extended attribute
> 
>          int removexattr(const char *path, const char *name)
>          int lremovexattr(const char *path, const char *name)
>          int fremovexattr(int fd, const char *name)
>          man page: 
> https://www.man7.org/linux/man-pages/man2/removexattr.2.html
> 
> Implementation notes:
> 
>     All of the syscalls have strings as argument types and thus a separate
>     printing function was stated in file "strace.list" for every one of them.
>     All of these printing functions were defined in "strace.c" using existing
>     printing functions for appropriate argument types:
>        "print_string()" - for (const char*) type
>        "print_pointer()" - for (char*) and (void *) type
>        "print_raw_param()" for (int) and (size_t) type
>     Syscalls "getxattr()" and "lgetxattr()" have the same number and type of
>     arguments and thus their print functions ("print_getxattr", 
> "print_lgetxattr")
>     share a same definition. The same statement applies to syscalls 
> "listxattr()"
>     and "llistxattr()".
>     Function "print_syscall_ret_listxattr()" was added to print the returned 
> list
>     of extended attributes for syscalls "print_listxattr(), 
> print_llistxattr() and
>     print_flistxattr()".
> 
> Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
> ---
>  linux-user/strace.c    | 121 +++++++++++++++++++++++++++++++++++++++++
>  linux-user/strace.list |  21 ++++---
>  2 files changed, 133 insertions(+), 9 deletions(-)
> 

Reviewed-by: Laurent Vivier <laurent@vivier.eu>