include/spawn.h

/****************************************************************************
 * include/spawn.h
 *
 *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

#ifndef __INCLUDE_SPAWN_H
#define __INCLUDE_SPAWN_H

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <sys/types.h>

#include <sched.h>
#include <signal.h>
#include <errno.h>

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/
/* Configuration ************************************************************/

#ifndef CONFIG_TASK_SPAWN_DEFAULT_STACKSIZE
#  define CONFIG_TASK_SPAWN_DEFAULT_STACKSIZE 2048
#endif

/* "The spawn.h header shall define the flags that may be set in a
 * posix_spawnattr_t object using the posix_spawnattr_setflags() function:"
 */

#define POSIX_SPAWN_RESETIDS      (1 << 0)  /* 1: Reset effective user ID */
#define POSIX_SPAWN_SETPGROUP     (1 << 1)  /* 1: Set process group */
#define POSIX_SPAWN_SETSCHEDPARAM (1 << 2)  /* 1: Set task's priority */
#define POSIX_SPAWN_SETSCHEDULER  (1 << 3)  /* 1: Set task's scheduler policy */
#define POSIX_SPAWN_SETSIGDEF     (1 << 4)  /* 1: Set default signal actions */
#define POSIX_SPAWN_SETSIGMASK    (1 << 5)  /* 1: Set sigmask */

/****************************************************************************
 * Type Definitions
 ****************************************************************************/
/* "The spawn.h header shall define the posix_spawnattr_t and
 * posix_spawn_file_actions_t types used in performing spawn operations.
 *
 * The internal structure underlying the posix_spawnattr_t is exposed here
 * because the user will be required to allocate this memory.
 */

struct posix_spawnattr_s
{
  /* Used by posix_spawn, posix_spawnp, and task_spawn */

  uint8_t  flags;                /* See POSIX_SPAWN_ definitions */
  uint8_t  priority;             /* Task scheduling priority */
  uint8_t  policy;               /* Task scheduling policy */
#ifndef CONFIG_DISABLE_SIGNALS
  sigset_t sigmask;              /* Signals to be masked */
#endif

  /* Used only by task_spawn (non-standard) */

  size_t   stacksize;            /* Task stack size */
};

typedef struct posix_spawnattr_s posix_spawnattr_t;

/* posix_spawn_file_actions_addclose(), posix_spawn_file_actions_adddup2(),
 * and posix_spawn_file_actions_addopen() will allocate memory and append
 * a new file action to an instance of posix_spawn_file_actions_t.  The
 * internal representation of these structures is not exposed to the user.
 * The user need only know that the size sizeof(posix_spawn_file_actions_t)
 * will hold a pointer to data.
 */

typedef FAR void *posix_spawn_file_actions_t;

/****************************************************************************
 * Public Function Prototypes
 ****************************************************************************/
/* "The following shall be declared as functions and may also be defined as
 * macros. Function prototypes shall be provided."
 */

#ifdef __cplusplus
extern "C"
{
#endif

/* Spawn interfaces *********************************************************/
/* Standard posix_spawn[p] interfaces.  These functions execute files in the
 * file system at 'path'
 */

#ifdef CONFIG_BINFMT_EXEPATH
int posix_spawnp(FAR pid_t *pid, FAR const char *path,
      FAR const posix_spawn_file_actions_t *file_actions,
      FAR const posix_spawnattr_t *attr,
      FAR char *const argv[], FAR char *const envp[]);
#define posix_spawn(pid,path,file_actions,attr,argv,envp) \
      posix_spawnp(pid,path,file_actions,attr,argv,envp)
#else
int posix_spawn(FAR pid_t *pid, FAR const char *path,
      FAR const posix_spawn_file_actions_t *file_actions,
      FAR const posix_spawnattr_t *attr,
      FAR char *const argv[], FAR char *const envp[]);
#define posix_spawnp(pid,path,file_actions,attr,argv,envp) \
      posix_spawn(pid,path,file_actions,attr,argv,envp)
#endif

/* Non-standard task_spawn interface.  This function uses the same
 * semantics to execute a file in memory at 'entry', giving it the name
 * 'name'.
 */

int task_spawn(FAR pid_t *pid, FAR const char *name, main_t entry,
      FAR const posix_spawn_file_actions_t *file_actions,
      FAR const posix_spawnattr_t *attr,
      FAR char *const argv[], FAR char *const envp[]);

/* File action interfaces ***************************************************/
/* File action initialization and destruction */

int posix_spawn_file_actions_init(FAR posix_spawn_file_actions_t *file_actions);
int posix_spawn_file_actions_destroy(FAR posix_spawn_file_actions_t *file_actions);

/* Add file action interfaces */

int posix_spawn_file_actions_addclose(FAR posix_spawn_file_actions_t *file_actions,
      int fd);
int posix_spawn_file_actions_adddup2(FAR posix_spawn_file_actions_t *file_actions,
      int fd1, int fd2);
int posix_spawn_file_actions_addopen(FAR posix_spawn_file_actions_t *file_actions,
      int fd, FAR const char *path, int oflags, mode_t mode);

/* Spawn attributes interfaces **********************************************/
/* Spawn attributes initialization and destruction */

int posix_spawnattr_init(FAR posix_spawnattr_t *attr);

/* int posix_spawnattr_destroy(FAR posix_spawnattr_t *); */
#ifdef CONFIG_DEBUG
#  define posix_spawnattr_destroy(attr) (attr ? 0 : EINVAL)
#else
#  define posix_spawnattr_destroy(attr) (0)
#endif

/* Get spawn attributes interfaces */

int posix_spawnattr_getflags(FAR const posix_spawnattr_t *attr, FAR short *flags);
#define posix_spawnattr_getpgroup(attr,group) (ENOSYS)
int posix_spawnattr_getschedparam(FAR const posix_spawnattr_t *attr,
      FAR struct sched_param *param);
int posix_spawnattr_getschedpolicy(FAR const posix_spawnattr_t *attr,
      FAR int *policy);
#define posix_spawnattr_getsigdefault(attr,sigdefault) (ENOSYS)
#ifndef CONFIG_DISABLE_SIGNALS
int posix_spawnattr_getsigmask(FAR const posix_spawnattr_t *attr,
                               FAR sigset_t *sigmask);
#else
#  define posix_spawnattr_getsigmask(attr,sigmask) (ENOSYS)
#endif

/* Set spawn attributes interfaces */

int posix_spawnattr_setflags(FAR posix_spawnattr_t *attr, short flags);
#define posix_spawnattr_setpgroup(attr,group) (ENOSYS)
int posix_spawnattr_setschedparam(FAR posix_spawnattr_t *attr,
      FAR const struct sched_param *param);
int posix_spawnattr_setschedpolicy(FAR posix_spawnattr_t *attr, int policy);
#define posix_spawnattr_setsigdefault(attr,sigdefault) (ENOSYS)
#ifndef CONFIG_DISABLE_SIGNALS
int posix_spawnattr_setsigmask(FAR posix_spawnattr_t *attr,
                               FAR const sigset_t *sigmask);
#else
#  define posix_spawnattr_setsigmask(attr,sigmask) (ENOSYS)
#endif

/* Non-standard get/set spawn attributes interfaces for use only with
 * task_spawn()
 */

int task_spawnattr_getstacksize(FAR const posix_spawnattr_t *attr,
      size_t *stacksize);
int task_spawnattr_setstacksize(FAR posix_spawnattr_t *attr,
      size_t stacksize);

/* Non standard debug functions */

#ifdef CONFIG_DEBUG
void posix_spawn_file_actions_dump(FAR posix_spawn_file_actions_t *file_actions);
void posix_spawnattr_dump(FAR posix_spawnattr_t *attr);
#else
#  define posix_spawn_file_actions_dump(fa)
#  define posix_spawnattr_dump(a)
#endif

#ifdef __cplusplus
}
#endif

#endif /* __INCLUDE_SPAWN_H */