diff options
Diffstat (limited to 'nuttx/sched/task_posixspawn.c')
| -rw-r--r-- | nuttx/sched/task_posixspawn.c | 675 |
1 files changed, 0 insertions, 675 deletions
diff --git a/nuttx/sched/task_posixspawn.c b/nuttx/sched/task_posixspawn.c deleted file mode 100644 index e9ad1fc45..000000000 --- a/nuttx/sched/task_posixspawn.c +++ /dev/null @@ -1,675 +0,0 @@ -/**************************************************************************** - * sched/task_posixspawn.c - * - * 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. - * - ****************************************************************************/ - -/**************************************************************************** - * Included Files - ****************************************************************************/ - -#include <nuttx/config.h> - -#include <sys/wait.h> -#include <unistd.h> -#include <semaphore.h> -#include <signal.h> -#include <sched.h> -#include <fcntl.h> -#include <spawn.h> -#include <errno.h> -#include <assert.h> -#include <debug.h> - -#include <nuttx/binfmt/binfmt.h> -#include <nuttx/spawn.h> - -#include "os_internal.h" -#include "group_internal.h" - -/**************************************************************************** - * Private Types - ****************************************************************************/ - -struct spawn_parms_s -{ - int result; - 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; -}; - -/**************************************************************************** - * Public Data - ****************************************************************************/ - -/**************************************************************************** - * Private Data - ****************************************************************************/ - -static sem_t g_ps_parmsem = SEM_INITIALIZER(1); -#ifndef CONFIG_SCHED_WAITPID -static sem_t g_ps_execsem = SEM_INITIALIZER(0); -#endif -static struct spawn_parms_s g_ps_parms; - -/**************************************************************************** - * Private Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: spawn_semtake and spawn_semgive - * - * Description: - * Give and take semaphores - * - * Input Parameters: - * - * sem - The semaphore to act on. - * - * Returned Value: - * None - * - ****************************************************************************/ - -static void spawn_semtake(FAR sem_t *sem) -{ - int ret; - - do - { - ret = sem_wait(sem); - ASSERT(ret == 0 || errno == EINTR); - } - while (ret != 0); -} - -#define spawn_semgive(sem) sem_post(sem) - -/**************************************************************************** - * Name: 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.| - * - * path - The 'path' argument identifies the file to execute. If - * CONFIG_BINFMT_EXEPATH is defined, this may be either a relative or - * or an absolute path. Otherwise, it must be an absolute path. - * - * 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 ps_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. - * - * 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 spawn_exec(FAR pid_t *pidp, FAR const char *path, - FAR const posix_spawnattr_t *attr, - FAR char *const argv[]) -{ - struct sched_param param; - FAR const struct symtab_s *symtab; - int nsymbols; - int pid; - int ret = OK; - - DEBUGASSERT(path); - - /* Get the current symbol table selection */ - - exec_getsymtab(&symtab, &nsymbols); - - /* Disable pre-emption so that we can modify the task parameters after - * we start the new task; the new task will not actually begin execution - * until we re-enable pre-emption. - */ - - sched_lock(); - - /* Start the task */ - - pid = exec(path, (FAR const char **)argv, symtab, nsymbols); - if (pid < 0) - { - ret = errno; - sdbg("ERROR: exec failed: %d\n", ret); - goto errout; - } - - /* Return the task ID to the caller */ - - if (pid) - { - *pidp = pid; - } - - /* Now set the attributes. Note that we ignore all of the return values - * here because we have already successfully started the task. If we - * return an error value, then we would also have to stop the task. - */ - - if (attr) - { - /* If we are only setting the priority, then call sched_setparm() - * to set the priority of the of the new task. - */ - - if ((attr->flags & POSIX_SPAWN_SETSCHEDPARAM) != 0) - { - /* Get the priority from the attrributes */ - - param.sched_priority = attr->priority; - - /* If we are setting *both* the priority and the scheduler, - * then we will call sched_setscheduler() below. - */ - - if ((attr->flags & POSIX_SPAWN_SETSCHEDULER) == 0) - { - svdbg("Setting priority=%d for pid=%d\n", - param.sched_priority, pid); - - (void)sched_setparam(pid, ¶m); - } - } - - /* If we are only changing the scheduling policy, then reset - * the priority to the default value (the same as this thread) in - * preparation for the sched_setscheduler() call below. - */ - - else if ((attr->flags & POSIX_SPAWN_SETSCHEDULER) != 0) - { - (void)sched_getparam(0, ¶m); - } - - /* Are we setting the scheduling policy? If so, use the priority - * setting determined above. - */ - - if ((attr->flags & POSIX_SPAWN_SETSCHEDULER) != 0) - { - svdbg("Setting policy=%d priority=%d for pid=%d\n", - attr->policy, param.sched_priority, pid); - - (void)sched_setscheduler(pid, attr->policy, ¶m); - } - } - - /* Re-enable pre-emption and return */ - -errout: - sched_unlock(); - return ret; -} - -/**************************************************************************** - * Name: spawn_close, spawn_dup2, and spawn_open - * - * Description: - * Implement individual file actions - * - * Input Parameters: - * action - describes the action to be performed - * - * Returned Value: - * posix_spawn() and posix_spawnp() will return zero on success. - * Otherwise, an error number will be returned as the function return - * value to indicate the error. - * - ****************************************************************************/ - -static inline int spawn_close(FAR struct spawn_close_file_action_s *action) -{ - /* The return value from close() is ignored */ - - svdbg("Closing fd=%d\n", action->fd); - - (void)close(action->fd); - return OK; -} - -static inline int spawn_dup2(FAR struct spawn_dup2_file_action_s *action) -{ - int ret; - - /* Perform the dup */ - - svdbg("Dup'ing %d->%d\n", action->fd1, action->fd2); - - ret = dup2(action->fd1, action->fd2); - if (ret < 0) - { - int errcode = errno; - - sdbg("ERROR: dup2 failed: %d\n", errcode); - return errcode; - } - - return OK; -} - -static inline int spawn_open(FAR struct spawn_open_file_action_s *action) -{ - int fd; - int ret = OK; - - /* Open the file */ - - svdbg("Open'ing path=%s oflags=%04x mode=%04x\n", - action->path, action->oflags, action->mode); - - fd = open(action->path, action->oflags, action->mode); - if (fd < 0) - { - ret = errno; - sdbg("ERROR: open failed: %d\n", ret); - } - - /* Does the return file descriptor happen to match the required file - * desciptor number? - */ - - else if (fd != action->fd) - { - /* No.. dup2 to get the correct file number */ - - svdbg("Dup'ing %d->%d\n", fd, action->fd); - - ret = dup2(fd, action->fd); - if (ret < 0) - { - ret = errno; - sdbg("ERROR: dup2 failed: %d\n", ret); - } - - svdbg("Closing fd=%d\n", fd); - close(fd); - } - - return ret; -} - -/**************************************************************************** - * Name: spawn_proxy - * - * Description: - * Perform file_actions, then execute the task from the file system. - * - * Input Parameters: - * Standard task start-up parameters - * - * Returned Value: - * Standard task return value. - * - ****************************************************************************/ - -static int spawn_proxy(int argc, char *argv[]) -{ - FAR struct spawn_general_file_action_s *entry; - FAR const posix_spawnattr_t *attr = g_ps_parms.attr; - int ret = OK; - - /* Perform file actions and/or set a custom signal mask. We get here only - * if the file_actions parameter to posix_spawn[p] was non-NULL and/or the - * option to change the signal mask was selected. - */ - -#ifndef CONFIG_DISABLE_SIGNALS - DEBUGASSERT((g_ps_parms.file_actions && *g_ps_parms.file_actions) || - (attr && (attr->flags & POSIX_SPAWN_SETSIGMASK) != 0)); -#else - DEBUGASSERT(g_ps_parms.file_actions && *g_ps_parms.file_actions); -#endif - - /* Check if we need to change the signal mask */ - -#ifndef CONFIG_DISABLE_SIGNALS - if (attr && (attr->flags & POSIX_SPAWN_SETSIGMASK) != 0) - { - (void)sigprocmask(SIG_SETMASK, &attr->sigmask, NULL); - } - - /* Were we also requested to perform file actions? */ - - if (g_ps_parms.file_actions) -#endif - { - /* Execute each file action */ - - for (entry = (FAR struct spawn_general_file_action_s *)*g_ps_parms.file_actions; - entry && ret == OK; - entry = entry->flink) - { - switch (entry->action) - { - case SPAWN_FILE_ACTION_CLOSE: - ret = spawn_close((FAR struct spawn_close_file_action_s *)entry); - break; - - case SPAWN_FILE_ACTION_DUP2: - ret = spawn_dup2((FAR struct spawn_dup2_file_action_s *)entry); - break; - - case SPAWN_FILE_ACTION_OPEN: - ret = spawn_open((FAR struct spawn_open_file_action_s *)entry); - break; - - case SPAWN_FILE_ACTION_NONE: - default: - sdbg("ERROR: Unknown action: %d\n", entry->action); - ret = EINVAL; - break; - } - } - } - - /* Check for failures */ - - if (ret == OK) - { - /* Start the task */ - - ret = spawn_exec(g_ps_parms.pid, g_ps_parms.path, attr, - g_ps_parms.argv); - -#ifdef CONFIG_SCHED_HAVE_PARENT - if (ret == OK) - { - /* Change of the parent of the task we just spawned to our parent. - * What should we do in the event of a failure? - */ - - int tmp = task_reparent(0, *g_ps_parms.pid); - if (tmp < 0) - { - sdbg("ERROR: task_reparent() failed: %d\n", tmp); - } - } -#endif - } - - /* Post the semaphore to inform the parent task that we have completed - * what we need to do. - */ - - g_ps_parms.result = ret; -#ifndef CONFIG_SCHED_WAITPID - spawn_semgive(&g_ps_execsem); -#endif - return OK; -} - -/**************************************************************************** - * Public Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: posix_spawn - * - * Description: - * The posix_spawn() and posix_spawnp() functions will create a new, - * child task, constructed from a regular executable file. - * - * Input Parameters: - * - * pid - Upon successful completion, posix_spawn() and posix_spawnp() will - * return the task ID of the child task to the parent task, in the - * variable pointed to by a non-NULL 'pid' argument. If the 'pid' - * argument is a null pointer, the process ID of the child is not - * returned to the caller. - * - * path - The 'path' argument to posix_spawn() is the absolute path that - * identifies the file to execute. The 'path' argument to posix_spawnp() - * may also be a relative path and will be used to construct a pathname - * that identifies the file to execute. In the case of a relative path, - * the path prefix for the file will be obtained by a search of the - * directories passed as the environment variable PATH. - * - * NOTE: NuttX provides only one implementation: If - * CONFIG_BINFMT_EXEPATH is defined, then only posix_spawnp() behavior - * is supported; otherwise, only posix_spawn behavior is supported. - * - * 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. - * - * 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 - The envp[] argument is not used by NuttX and may be NULL. In - * standard implementations, envp[] is an array of character pointers to - * null-terminated strings that provide the environment for the new - * process image. The environment array is terminated by a null pointer. - * In NuttX, the envp[] argument is ignored and the new task will simply - * inherit the environment of the parent task. - * - * Returned Value: - * posix_spawn() and posix_spawnp() will return zero on success. - * Otherwise, an error 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. - * - * Assumptions/Limitations: - * - NuttX provides only posix_spawn() or posix_spawnp() behavior - * depending upon the setting of CONFIG_BINFMT_EXEPATH: If - * CONFIG_BINFMT_EXEPATH is defined, then only posix_spawnp() behavior - * is supported; otherwise, only posix_spawn behavior is supported. - * - The 'envp' argument is not used and the 'environ' variable is not - * altered (NuttX does not support the 'environ' variable). - * - Process groups are not supported (POSIX_SPAWN_SETPGROUP). - * - Effective user IDs are not supported (POSIX_SPAWN_RESETIDS). - * - Signal default actions cannot be modified in the newly task executed - * because NuttX does not support default signal actions - * (POSIX_SPAWN_SETSIGDEF). - * - * POSIX Compatibility - * - The value of the argv[0] received by the child task is assigned by - * NuttX. For the caller of posix_spawn(), the provided argv[0] will - * correspond to argv[1] received by the new task. - * - ****************************************************************************/ - -#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[]) -#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[]) -#endif -{ - struct sched_param param; - pid_t proxy; -#ifdef CONFIG_SCHED_WAITPID - int status; -#endif - int ret; - - DEBUGASSERT(path); - - svdbg("pid=%p path=%s file_actions=%p attr=%p argv=%p\n", - pid, path, file_actions, attr, argv); - - /* If there are no file actions to be performed and there is no change to - * the signal mask, then start the new child task directly from the parent task. - */ - -#ifndef CONFIG_DISABLE_SIGNALS - if ((file_actions == NULL || *file_actions == NULL) && - (attr == NULL || (attr->flags & POSIX_SPAWN_SETSIGMASK) == 0)) -#else - if (file_actions == NULL || *file_actions == NULL) -#endif - { - return spawn_exec(pid, path, attr, argv); - } - - /* Otherwise, we will have to go through an intermediary/proxy task in order - * to perform the I/O redirection. This would be a natural place to fork(). - * However, true fork() behavior requires an MMU and most implementations - * of vfork() are not capable of these operations. - * - * Even without fork(), we can still do the job, but parameter passing is - * messier. Unfortunately, there is no (clean) way to pass binary values - * as a task parameter, so we will use a semaphore-protected global - * structure. - */ - - /* Get exclusive access to the global parameter structure */ - - spawn_semtake(&g_ps_parmsem); - - /* Populate the parameter structure */ - - g_ps_parms.result = ENOSYS; - g_ps_parms.pid = pid; - g_ps_parms.path = path; - g_ps_parms.file_actions = file_actions; - g_ps_parms.attr = attr; - g_ps_parms.argv = argv; - - /* Get the priority of this (parent) task */ - - ret = sched_getparam(0, ¶m); - if (ret < 0) - { - int errcode = errno; - - sdbg("ERROR: sched_getparam failed: %d\n", errcode); - spawn_semgive(&g_ps_parmsem); - return errcode; - } - - /* Disable pre-emption so that the proxy does not run until we waitpid - * is called. This is probably unnecessary since the spawn_proxy has - * the same priority as this thread; it should be schedule behind this - * task in the ready-to-run list. - */ - -#ifdef CONFIG_SCHED_WAITPID - sched_lock(); -#endif - - /* Start the intermediary/proxy task at the same priority as the parent - * task. - */ - - proxy = TASK_CREATE("spawn_proxy", param.sched_priority, - CONFIG_POSIX_SPAWN_STACKSIZE, (main_t)spawn_proxy, - (FAR const char **)NULL); - if (proxy < 0) - { - ret = get_errno(); - sdbg("ERROR: Failed to start spawn_proxy: %d\n", ret); - - goto errout_with_lock; - } - - /* Wait for the proxy to complete its job */ - -#ifdef CONFIG_SCHED_WAITPID - ret = waitpid(proxy, &status, 0); - if (ret < 0) - { - sdbg("ERROR: waitpid() failed: %d\n", errno); - goto errout_with_lock; - } -#else - spawn_semtake(&g_ps_execsem); -#endif - - /* Get the result and relinquish our access to the parameter structure */ - - ret = g_ps_parms.result; - -errout_with_lock: -#ifdef CONFIG_SCHED_WAITPID - sched_unlock(); -#endif - spawn_semgive(&g_ps_parmsem); - return ret; -} |