/****************************************************************************
 * include/sys/prctl.h
 *
 *   Copyright (C) 2012-2013 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_SYS_PRCTL_H
#define __INCLUDE_SYS_PRCTL_H

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

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

/* Supported prctl() commands.
 *
 *  PR_SET_NAME
 *    Set the name of the calling thread, using the value in the location
 *    pointed to by (char *) arg2. The name can be up to
 *    CONFIG_TASK_NAME_SIZE long, including the terminating null byte.
 *    (If the length of the string, including the terminating null byte,
 *    exceeds CONFIG_TASK_NAME_SIZE bytes, the string is silently truncated.)
 *    As an example:
 *
 *      prctl(PR_SET_NAME, "MyName");
 *
 *  PR_GET_NAME
 *    Return the name of the calling thread, in the buffer pointed to by
 *    (char *) arg2.  The buffer should allow space for up to
 *    CONFIG_TASK_NAME_SIZE bytes; the returned string will be
 *    null-terminated. As an example:
 *
 *      char myname[CONFIG_TASK_NAME_SIZE];
 *      prctl(PR_GET_NAME, myname);
 *
 *  PR_SET_NAME_EXT
 *    Set the task (or thread) name for the thread whose ID is in required
 *    arg2 (int), using the value in the location pointed to by required arg1
 *    (char*).  The name can be up to CONFIG_TASK_NAME_SIZE long (including
 *    any null termination).  The thread ID of 0 will set the name of the
 *    calling thread. As an example:
 *
 *      prctl(PR_SET_NAME_EXT, "MyName", pid);
 *
 *  PR_GET_NAME_EXT
 *    Return the task (or thread) name for the for the thread whose ID is
 *    optional arg2 (int), in the buffer pointed to by optional arg1
 *    (char *). The buffer must be CONFIG_TASK_NAME_SIZE long (including
 *    any null termination). As an example:
 *
 *      char myname[CONFIG_TASK_NAME_SIZE];
 *      prctl(PR_GET_NAME_EXT, myname, pid);
 */

#define PR_SET_NAME     1
#define PR_GET_NAME     2
#define PR_SET_NAME_EXT 3
#define PR_GET_NAME_EXT 4

/****************************************************************************
 * Public Type Definitions
 ****************************************************************************/

/****************************************************************************
 * Public Function Prototypes
 ****************************************************************************/

#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif

/****************************************************************************
 * Name: prctl
 *
 * Description:
 *   prctl() is called with a first argument describing what to do (with
 *   values PR_* defined above) and with additional arguments depending on
 *   the specific command.
 *
 * Returned Value:
 *   The returned value may depend on the specific command.  For PR_SET_NAME
 *   and PR_GET_NAME, the returned value of 0 indicates successful operation.
 *   On any failure, -1 is retruend and the errno value is set appropriately.
 *
 *     EINVAL The value of 'option' is not recognized.
 *     EFAULT optional arg1 is not a valid address.
 *     ESRCH  No task/thread can be found corresponding to that specified
 *       by optional arg1.
 *
 ****************************************************************************/

int prctl(int option, ...);

#undef EXTERN
#if defined(__cplusplus)
}
#endif

#endif /* __INCLUDE_SYS_PRCTL_H */