/****************************************************************************
* sched/task/task_spawn.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/wait.h>
#include <sched.h>
#include <spawn.h>
#include <assert.h>
#include <debug.h>
#include <errno.h>
#include <nuttx/fs/fs.h>
#include <nuttx/sched.h>
#include <nuttx/kthread.h>
#include <nuttx/spawn.h>
#include "sched/sched.h"
#include "group/group.h"
#include "task/spawn.h"
#include "task/task.h"
#ifndef CONFIG_BUILD_KERNEL
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: nxtask_spawn_create
*
* Description:
* This function creates and activates a new thread of the specified type
* with a specified priority and returns its system-assigned ID. It is the
* internal, common implementation of task_create() and kthread_create().
* See comments with task_create() for further information.
*
* Input Parameters:
* name - Name of the new task
* ttype - Type of the new task
* priority - Priority of the new task
* stack_addr - Address of the stack needed
* stack_size - Size (in bytes) of the stack needed
* entry - Entry point of a new task
* arg - A pointer to an array of input parameters. The array
* should be terminated with a NULL argv[] value. If no
* parameters are required, argv may be NULL.
* envp - A pointer to an array of environment strings. Terminated
* with a NULL entry.
* actions - The spawn file actions
*
* Returned Value:
* Returns the positive, non-zero process ID of the new task or a negated
* errno value to indicate the nature of any failure. If memory is
* insufficient or the task cannot be created -ENOMEM will be returned.
*
****************************************************************************/
static int nxtask_spawn_create(FAR const char *name, int priority,
FAR void *stack_addr, int stack_size,
main_t entry, FAR char * const argv[],
FAR char * const envp[],
FAR const posix_spawn_file_actions_t *actions,
FAR const posix_spawnattr_t *attr)
{
FAR struct task_tcb_s *tcb;
pid_t pid;
int ret;
/* Allocate a TCB for the new task. */
tcb = kmm_zalloc(sizeof(struct task_tcb_s));
if (tcb == NULL)
{
serr("ERROR: Failed to allocate TCB\n");
return -ENOMEM;
}
/* Setup the task type */
tcb->cmn.flags = TCB_FLAG_TTYPE_TASK;
/* Initialize the task */
ret = nxtask_init(tcb, name, priority, stack_addr, stack_size,
entry, argv, envp, actions);
if (ret < OK)
{
kmm_free(tcb);
return ret;
}
/* Get the assigned pid before we start the task */
pid = tcb->cmn.pid;
/* Set the attributes */
if (attr)
{
ret = spawn_execattrs(pid, attr);
if (ret < 0)
{
goto errout_with_taskinit;
}
}
/* Activate the task */
nxtask_activate(&tcb->cmn);
return pid;
errout_with_taskinit:
nxtask_uninit(tcb);
return ret;
}
/****************************************************************************
* Name: nxtask_spawn_exec
*
* Description:
* Execute the task from the file system.
*
* Input Parameters:
*
* pidp - Upon successful completion, this will return the task ID of the
* child task in the variable pointed to by a non-NULL 'pid' argument.|
*
* name - The name to assign to the child task.
*
* entry - The child task's entry point (an address in memory)
*
* actions - The spawn file actions
*
* attr - If the value of the 'attr' parameter is NULL, the all default
* values for the POSIX spawn attributes will be used. Otherwise, the
* attributes will be set according to the spawn flags. The
* following spawn flags are supported:
*
* - POSIX_SPAWN_SETSCHEDPARAM: Set new tasks priority to the sched_param
* value.
* - POSIX_SPAWN_SETSCHEDULER: Set the new tasks scheduler priority to
* the sched_policy value.
*
* NOTE: POSIX_SPAWN_SETSIGMASK is handled in nxtask_spawn_proxy().
*
* argv - argv[] is the argument list for the new task. argv[] is an
* array of pointers to null-terminated strings. The list is terminated
* with a null pointer.
*
* envp - A pointer to an array of environment strings. Terminated with
* a NULL entry.
*
* Returned Value:
* This function will return zero on success. Otherwise, an error number
* will be returned as the function return value to indicate the error.
* This errno value may be that set by execv(), sched_setpolicy(), or
* sched_setparam().
*
****************************************************************************/
static int nxtask_spawn_exec(FAR pid_t *pidp, FAR const char *name,
main_t entry,
FAR const posix_spawn_file_actions_t *actions,
FAR const posix_spawnattr_t *attr,
FAR char * const *argv, FAR char * const envp[])
{
FAR void *stackaddr = NULL;
size_t stacksize;
int priority;
int pid;
int ret = OK;
/* Use the default priority and stack size if no attributes are provided */
if (attr)
{
priority = attr->priority;
stacksize = attr->stacksize;
stackaddr = attr->stackaddr;
}
else
{
struct sched_param param;
/* Set the default priority to the same priority as this task */
ret = nxsched_get_param(0, ¶m);
if (ret < 0)
{
return ret;
}
priority = param.sched_priority;
stacksize = CONFIG_POSIX_SPAWN_DEFAULT_STACKSIZE;
}
/* Start the task */
pid = nxtask_spawn_create(name, priority, stackaddr,
stacksize, entry, argv,
envp ? envp : environ, actions, attr);
if (pid < 0)
{
ret = pid;
serr("ERROR: nxtask_spawn_create failed: %d\n", ret);
return ret;
}
/* Return the task ID to the caller */
if (pid)
{
*pidp = pid;
}
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: task_spawn
*
* Description:
* The task_spawn() function will create a new, child task, where the
* entry point to the task is an address in memory.
*
* Input Parameters:
*
* name - The name to assign to the child task.
*
* entry - The child task's entry point (an address in memory)
*
* file_actions - If 'file_actions' is a null pointer, then file
* descriptors open in the calling process will remain open in the
* child process (unless CONFIG_FDCLONE_STDIO is defined). If
* 'file_actions' is not NULL, then the file descriptors open in the
* child process will be those open in the calling process as modified
* by the spawn file actions object pointed to by file_actions.
*
* attr - If the value of the 'attr' parameter is NULL, the all default
* values for the POSIX spawn attributes will be used. Otherwise, the
* attributes will be set according to the spawn flags. The
* posix_spawnattr_t spawn attributes object type is defined in spawn.h.
* It will contains these attributes, not all of which are supported by
* NuttX:
*
* - POSIX_SPAWN_SETPGROUP: Setting of the new task's process group is
* not supported. NuttX does not support process groups.
* - POSIX_SPAWN_SETSCHEDPARAM: Set new tasks priority to the sched_param
* value.
* - POSIX_SPAWN_SETSCHEDULER: Set the new task's scheduler policy to
* the sched_policy value.
* - POSIX_SPAWN_RESETIDS: Resetting of the effective user ID of the
* child process is not supported. NuttX does not support effective
* user IDs.
* - POSIX_SPAWN_SETSIGMASK: Set the new task's signal mask.
* - POSIX_SPAWN_SETSIGDEF: Resetting signal default actions is not
* supported. NuttX does not support default signal actions.
*
* And the non-standard:
*
* - TASK_SPAWN_SETSTACKSIZE: Set the stack size for the new task.
*
* argv - argv[] is the argument list for the new task. argv[] is an
* array of pointers to null-terminated strings. The list is terminated
* with a null pointer.
*
* envp - envp[] is an array of character pointers to null-terminated
* strings that provide the environment for the new process image.
*
* Returned Value:
* task_spawn() will return process ID of new task on success.
* Otherwise, a negative number will be returned as the function return
* value to indicate the error:
*
* - EINVAL: The value specified by 'file_actions' or 'attr' is invalid.
* - Any errors that might have been return if vfork() and excec[l|v]()
* had been called.
*
****************************************************************************/
int task_spawn(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[])
{
pid_t pid = INVALID_PROCESS_ID;
int ret;
sinfo("name=%s entry=%p file_actions=%p attr=%p argv=%p\n",
name, entry, file_actions, attr, argv);
ret = nxtask_spawn_exec(&pid, name, entry,
file_actions != NULL ? *file_actions : NULL,
attr, argv, envp);
return ret >= 0 ? pid : ret;
}
#endif /* CONFIG_BUILD_KERNEL */