Re: [PATCH] exec: add proper argument parsing, add --device-master-port

[Samuel Thibault]

Justus Winter, le Tue 23 Sep 2014 12:33:06 +0200, a écrit :
> If the device master port is given, a boot-time exec server can print
> diagnostic messages earlier.

Ack.

> * exec/main.c (opt_device_master): New variable.
> (OPT_DEVICE_MASTER_PORT): New macro.
> (options): New set of options.
> (parse_opt): New function.
> (trivfs_append_args): Likewise.
> (argp): Pull the argp definition out of main.
> (trivfs_runtime_argp): Set, so that we respond properly to fsysopts.
> (open_console): Pull the code out of S_exec_init and generalize it.
> (main): Call open_console if a device master port is given.
> (S_exec_init): Call open_console.
> ---
>  exec/main.c | 106 
> ++++++++++++++++++++++++++++++++++++++++++++++++++++--------
>  1 file changed, 93 insertions(+), 13 deletions(-)
> 
> diff --git a/exec/main.c b/exec/main.c
> index 78faebd..784000b 100644
> --- a/exec/main.c
> +++ b/exec/main.c
> @@ -45,6 +45,7 @@ int trivfs_cntl_nportclasses = 1;
>  struct trivfs_control *fsys;
>  
>  char **save_argv;
> +mach_port_t opt_device_master;
>  
>  
>  #include "exec_S.h"
> @@ -104,16 +105,104 @@ deadboot (void *p)
>    ports_enable_class (trivfs_cntl_portclasses[0]);
>  }
>  
> +#define OPT_DEVICE_MASTER_PORT       (-1)
> +
> +static const struct argp_option options[] =
> +{
> +  {"device-master-port", OPT_DEVICE_MASTER_PORT, "PORT", 0,
> +   "If specified, a boot-time exec server can print "
> +   "diagnostic messages earlier.", 0},
> +  {0}
> +};
> +
> +static error_t
> +parse_opt (int opt, char *arg, struct argp_state *state)
> +{
> +  switch (opt)
> +    {
> +    default:
> +      return ARGP_ERR_UNKNOWN;
> +    case ARGP_KEY_INIT:
> +    case ARGP_KEY_SUCCESS:
> +    case ARGP_KEY_ERROR:
> +      break;
> +
> +    case OPT_DEVICE_MASTER_PORT:
> +      opt_device_master = atoi (arg);
> +      break;
> +    }
> +  return 0;
> +}
> +
> +/* This will be called from libtrivfs to help construct the answer
> +   to an fsys_get_options RPC.  */
> +error_t
> +trivfs_append_args (struct trivfs_control *fsys,
> +                 char **argz, size_t *argz_len)
> +{
> +  error_t err = 0;
> +  char *opt;
> +
> +  if (MACH_PORT_VALID (opt_device_master))
> +    {
> +      asprintf (&opt, "--device-master-port=%d", opt_device_master);
> +
> +      if (opt)
> +     {
> +       err = argz_add (argz, argz_len, opt);
> +       free (opt);
> +     }
> +    }
> +
> +  return err;
> +}
> +
> +static struct argp argp =
> +{ options, parse_opt, 0, "Hurd standard exec server." };
> +
> +/* Setting this variable makes libtrivfs use our argp to
> +   parse options passed in an fsys_set_options RPC.  */
> +struct argp *trivfs_runtime_argp = &argp;
> +
> +/* Get our stderr set up to print on the console, in case we have to
> +   panic or something.  */
> +error_t
> +open_console (mach_port_t device_master)
> +{
> +  static int got_console = 0;
> +  mach_port_t cons;
> +  error_t err;
> +
> +  if (got_console)
> +    return 0;
> +
> +  err = device_open (device_master, D_READ|D_WRITE, "console", &cons);
> +  if (err)
> +    return err;
> +
> +  stdin = mach_open_devstream (cons, "r");
> +  stdout = stderr = mach_open_devstream (cons, "w");
> +
> +  got_console = 1;
> +  mach_port_deallocate (mach_task_self (), cons);
> +  return 0;
> +}
>  
>  int
>  main (int argc, char **argv)
>  {
>    error_t err;
>    mach_port_t bootstrap;
> -  struct argp argp = { 0, 0, 0, "Hurd standard exec server." };
>  
>    argp_parse (&argp, argc, argv, 0, 0, 0);
>  
> +  if (MACH_PORT_VALID (opt_device_master))
> +    {
> +      err = open_console (opt_device_master);
> +      assert_perror (err);
> +      mach_port_deallocate (mach_task_self (), opt_device_master);
> +    }
> +
>    save_argv = argv;
>  
>    task_get_bootstrap_port (mach_task_self (), &bootstrap);
> @@ -236,18 +325,9 @@ S_exec_init (struct trivfs_protid *protid,
>    err = get_privileged_ports (&host_priv, &device_master);
>    assert_perror (err);
>  
> -  {
> -    /* Get our stderr set up to print on the console, in case we have
> -       to panic or something.  */
> -    mach_port_t cons;
> -    error_t err;
> -    err = device_open (device_master, D_READ|D_WRITE, "console", &cons);
> -    assert_perror (err);
> -    mach_port_deallocate (mach_task_self (), device_master);
> -    stdin = mach_open_devstream (cons, "r");
> -    stdout = stderr = mach_open_devstream (cons, "w");
> -    mach_port_deallocate (mach_task_self (), cons);
> -  }
> +  err = open_console (device_master);
> +  assert_perror (err);
> +  mach_port_deallocate (mach_task_self (), device_master);
>  
>    proc_register_version (procserver, host_priv, "exec", "", HURD_VERSION);
>  
> -- 
> 2.1.0
> 

-- 
Samuel
<N>  sl  -  display animations aimed to correct users who accidentally enter
<N>        sl instead of ls.