Re: [PATCH][BZ 21340] add support for POSIX_SPAWN_SETSID

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

It lacks the proper Changelog, but patch looks good.  Could you provide
one? Also, I assume you checked at least in one architecture (we usually
indicate which system we ran the patch and the results).

On 01/04/2017 11:29, daurnimator wrote:
> This patch adds support for the POSIX_SPAWN_SETSID flag.
> 
> It was recently accepted by the Austin Group:
> http://austingroupbugs.net/view.php?id=1044
> 
> ---
>  conform/data/spawn.h-data        | 1 +
>  posix/spawn.h                    | 1 +
>  posix/spawnattr_setflags.c       | 1 +
>  sysdeps/mach/hurd/spawni.c       | 3 +++
>  sysdeps/posix/spawni.c           | 7 ++++++-
>  sysdeps/unix/sysv/linux/spawni.c | 4 ++++
>  6 files changed, 16 insertions(+), 1 deletion(-)
> 
> diff --git a/conform/data/spawn.h-data b/conform/data/spawn.h-data
> index fb206f7ecf..bcba36c492 100644
> --- a/conform/data/spawn.h-data
> +++ b/conform/data/spawn.h-data
> @@ -14,6 +14,7 @@ constant POSIX_SPAWN_SETSCHEDPARAM
>  constant POSIX_SPAWN_SETSCHEDULER
>  constant POSIX_SPAWN_SETSIGDEF
>  constant POSIX_SPAWN_SETSIGMASK
> +constant POSIX_SPAWN_SETSID
>  
>  function int posix_spawnattr_destroy (posix_spawnattr_t*)
>  function int posix_spawnattr_getsigdefault (const posix_spawnattr_t*, sigset_t*)
> diff --git a/posix/spawn.h b/posix/spawn.h
> index 36e3867e17..8d2ace1b87 100644
> --- a/posix/spawn.h
> +++ b/posix/spawn.h
> @@ -60,6 +60,7 @@ typedef struct
>  #ifdef __USE_GNU
>  # define POSIX_SPAWN_USEVFORK		0x40
>  #endif
> +#define POSIX_SPAWN_SETSID		0x80
>  
>  
>  __BEGIN_DECLS
> diff --git a/posix/spawnattr_setflags.c b/posix/spawnattr_setflags.c
> index 9b3d1e022a..62d2f00c20 100644
> --- a/posix/spawnattr_setflags.c
> +++ b/posix/spawnattr_setflags.c
> @@ -25,6 +25,7 @@
>  		   | POSIX_SPAWN_SETSIGMASK				      \
>  		   | POSIX_SPAWN_SETSCHEDPARAM				      \
>  		   | POSIX_SPAWN_SETSCHEDULER				      \
> +		   | POSIX_SPAWN_SETSID					      \
>  		   | POSIX_SPAWN_USEVFORK)
>  
>  /* Store flags in the attribute structure.  */
> diff --git a/sysdeps/mach/hurd/spawni.c b/sysdeps/mach/hurd/spawni.c
> index 284875ac30..74303839e4 100644
> --- a/sysdeps/mach/hurd/spawni.c
> +++ b/sysdeps/mach/hurd/spawni.c
> @@ -281,6 +281,9 @@ __spawni (pid_t *pid, const char *file,
>      }
>  #endif
>  
> +  if (!err && (flags & POSIX_SPAWN_SETSID) != 0)
> +    err = __proc_setsid (proc);
> +
>    /* Set the process group ID.  */
>    if (!err && (flags & POSIX_SPAWN_SETPGROUP) != 0)
>      err = __proc_setpgrp (proc, new_pid, attrp->__pgrp);
> diff --git a/sysdeps/posix/spawni.c b/sysdeps/posix/spawni.c
> index 5cc2ad1363..bc23a1e6ab 100644
> --- a/sysdeps/posix/spawni.c
> +++ b/sysdeps/posix/spawni.c
> @@ -101,7 +101,8 @@ __spawni (pid_t *pid, const char *file,
>  	 to POSIX.  */
>        || ((flags & (POSIX_SPAWN_SETSIGMASK | POSIX_SPAWN_SETSIGDEF
>  		    | POSIX_SPAWN_SETSCHEDPARAM | POSIX_SPAWN_SETSCHEDULER
> -		    | POSIX_SPAWN_SETPGROUP | POSIX_SPAWN_RESETIDS)) == 0
> +		    | POSIX_SPAWN_SETPGROUP | POSIX_SPAWN_RESETIDS
> +		    | POSIX_SPAWN_SETSID)) == 0
>  	  && file_actions == NULL))
>      new_pid = __vfork ();
>    else
> @@ -159,6 +160,10 @@ __spawni (pid_t *pid, const char *file,
>      }
>  #endif
>  
> +  if ((flags & POSIX_SPAWN_SETSID) != 0
> +      && __setsid () != 0)
> +    _exit (SPAWN_ERROR);
> +
>    /* Set the process group ID.  */
>    if ((flags & POSIX_SPAWN_SETPGROUP) != 0
>        && __setpgid (0, attrp->__pgrp) != 0)
> diff --git a/sysdeps/unix/sysv/linux/spawni.c b/sysdeps/unix/sysv/linux/spawni.c
> index b82a5e8f3c..318c39a8af 100644
> --- a/sysdeps/unix/sysv/linux/spawni.c
> +++ b/sysdeps/unix/sysv/linux/spawni.c
> @@ -177,6 +177,10 @@ __spawni_child (void *arguments)
>      }
>  #endif
>  
> +  if ((attr->__flags & POSIX_SPAWN_SETSID) != 0
> +      && (ret = __setsid ()) != 0)
> +    goto fail;
> +
>    /* Set the process group ID.  */
>    if ((attr->__flags & POSIX_SPAWN_SETPGROUP) != 0
>        && (ret = __setpgid (0, attr->__pgrp)) != 0)
>