[PATCH 4/7] nss_files: Allocate nscd file registration data on the heap

[Adhemerval Zanella]

On 29/06/2021 07:11, Florian Weimer via Libc-alpha wrote:
> This is only needed if nss_files is loaded by nscd.
> 
> Before:
> 
>    text	   data	    bss	    dec	    hex	filename
>     767	      0	  24952	  25719	   6477	nss/files-init.os
> 
> After:
> 
>    text	   data	    bss	    dec	    hex	filename
>     666	      0	      0	    666	    29a	nss/files-init.os
> 
> Using PATH_MAX bytes unconditionally for the directory name
> is wasteful, but fixing that would constitute another break
> of this semi-public ABI.  (The other issue is that with
> symbolic links, an arbitrary set of parent directories may need
> watching, not just a single one.)

LGTM, only a nit below.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

> ---
>  nss/nss_files/files-init.c | 54 ++++++++++++++------------------------
>  1 file changed, 20 insertions(+), 34 deletions(-)
> 
> diff --git a/nss/nss_files/files-init.c b/nss/nss_files/files-init.c
> index cc22330640..36d5ebce1f 100644
> --- a/nss/nss_files/files-init.c
> +++ b/nss/nss_files/files-init.c
> @@ -24,44 +24,30 @@
>  
>  NSS_DECLARE_MODULE_FUNCTIONS (files)
>  
> -#define PWD_FILENAME "/etc/passwd"
> -define_traced_file (pwd, PWD_FILENAME);
> -
> -#define GRP_FILENAME "/etc/group"
> -define_traced_file (grp, GRP_FILENAME);
> -
> -#define HST_FILENAME "/etc/hosts"
> -define_traced_file (hst, HST_FILENAME);
> -
> -#define RESOLV_FILENAME "/etc/resolv.conf"
> -define_traced_file (resolv, RESOLV_FILENAME);
> -
> -#define SERV_FILENAME "/etc/services"
> -define_traced_file (serv, SERV_FILENAME);
> -
> -#define NETGR_FILENAME "/etc/netgroup"
> -define_traced_file (netgr, NETGR_FILENAME);
> +static void
> +register_file (void (*cb) (size_t, struct traced_file *),
> +               int db, const char *path, int crinit)
> +{
> +  size_t pathlen = strlen (path) + 1;
> +  struct traced_file *file = malloc (sizeof (struct traced_file) + pathlen);
> +  /* Do not register anything on memory allocation file.  nscd will

I think you mean 'fail' instead of 'file' here.

> +     fail soon anyway.  */
> +  if (file != NULL)
> +    {
> +      init_traced_file (file, path, crinit);
> +      cb (db, file);
> +    }
> +}
>  
>  void
>  _nss_files_init (void (*cb) (size_t, struct traced_file *))
>  {
> -  init_traced_file (&pwd_traced_file.file, PWD_FILENAME, 0);
> -  cb (pwddb, &pwd_traced_file.file);
> -
> -  init_traced_file (&grp_traced_file.file, GRP_FILENAME, 0);
> -  cb (grpdb, &grp_traced_file.file);
> -
> -  init_traced_file (&hst_traced_file.file, HST_FILENAME, 0);
> -  cb (hstdb, &hst_traced_file.file);
> -
> -  init_traced_file (&resolv_traced_file.file, RESOLV_FILENAME, 1);
> -  cb (hstdb, &resolv_traced_file.file);
> -
> -  init_traced_file (&serv_traced_file.file, SERV_FILENAME, 0);
> -  cb (servdb, &serv_traced_file.file);
> -
> -  init_traced_file (&netgr_traced_file.file, NETGR_FILENAME, 0);
> -  cb (netgrdb, &netgr_traced_file.file);
> +  register_file (cb, pwddb, "/etc/passwd", 0);
> +  register_file (cb, grpdb, "/etc/group", 0);
> +  register_file (cb, hstdb, "/etc/hosts", 0);
> +  register_file (cb, hstdb, "/etc/resolv.conf", 1);
> +  register_file (cb, servdb, "/etc/services", 0);
> +  register_file (cb, netgrdb, "/etc/netgroup", 0);
>  }
>  
>  #endif
> 

Ok.