diff options
Diffstat (limited to 'nuttx/binfmt/binfmt_schedunload.c')
-rw-r--r-- | nuttx/binfmt/binfmt_schedunload.c | 333 |
1 files changed, 0 insertions, 333 deletions
diff --git a/nuttx/binfmt/binfmt_schedunload.c b/nuttx/binfmt/binfmt_schedunload.c deleted file mode 100644 index 972d17963..000000000 --- a/nuttx/binfmt/binfmt_schedunload.c +++ /dev/null @@ -1,333 +0,0 @@ -/**************************************************************************** - * binfmt/binfmt_schedunload.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 <sched.h> -#include <debug.h> -#include <errno.h> - -#include <nuttx/kmalloc.h> -#include <nuttx/binfmt/binfmt.h> - -#include "binfmt_internal.h" - -#if !defined(CONFIG_BINFMT_DISABLE) && defined(CONFIG_SCHED_HAVE_PARENT) - -/**************************************************************************** - * Pre-processor Definitions - ****************************************************************************/ - -/**************************************************************************** - * Private Function Prototypes - ****************************************************************************/ - -/**************************************************************************** - * Private Data - ****************************************************************************/ - -FAR struct binary_s *g_unloadhead; - -/**************************************************************************** - * Private Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: unload_list_add - * - * Description: - * If CONFIG_SCHED_HAVE_PARENT is defined then schedul_unload() will - * manage instances of struct binary_s allocated with kmalloc. It - * will keep the binary data in a link list and when SIGCHLD is received - * (meaning that the task has exit'ed, schedul_unload() will find the - * data, unload the module, and free the structure. - * - * This function will add one structure to the linked list - * - * Input Parameter: - * pid - The task ID of the child task - * bin - This structure must have been allocated with kmalloc() and must - * persist until the task unloads - - * - * Returned Value: - * None - * - ****************************************************************************/ - -static void unload_list_add(pid_t pid, FAR struct binary_s *bin) -{ - irqstate_t flags; - - /* Save the PID in the structure so that we recover it later */ - - bin->pid = pid; - - /* Disable deliver of any signals while we muck with the list. The graceful - * way to do this would be block delivery of SIGCHLD would be with - * sigprocmask. Here we do it the quick'n'dirty way by just disabling - * interrupts. - */ - - flags = irqsave(); - bin->flink = g_unloadhead; - g_unloadhead = bin; - irqrestore(flags); -} - -/**************************************************************************** - * Name: unload_list_remove - * - * Description: - * If CONFIG_SCHED_HAVE_PARENT is defined then schedul_unload() will - * manage instances of struct binary_s allocated with kmalloc. It - * will keep the binary data in a link list and when SIGCHLD is received - * (meaning that the task has exit'ed, schedul_unload() will find the - * data, unload the module, and free the structure. - * - * This function will remove one structure to the linked list - * - * Input Parameter: - * pid - The task ID of the child task - * - * Returned Value: - * On success, the load structure is returned. NULL is returned on - * failure. - * - ****************************************************************************/ - -static FAR struct binary_s *unload_list_remove(pid_t pid) -{ - FAR struct binary_s *curr; - FAR struct binary_s *prev; - - /* Note the asymmetry. We do not have to disable interrupts here because - * the main thread cannot run while we are in the interrupt handler. Here, - * it should be sufficient to disable pre-emption so that no other thread - * can run. - */ - - sched_lock(); - - /* Find the structure in the unload list with the matching PID */ - - for (prev = NULL, curr = g_unloadhead; - curr && (curr->pid != pid); - prev = curr, curr = curr->flink); - - /* Did we find it? It must be there. Hmmm.. we should probably ASSERT if - * we do not! - */ - - if (curr) - { - /* Was there another entry before this one? */ - - if (prev) - { - /* Yes.. remove the current entry from after the previous entry */ - - prev->flink = curr->flink; - } - else - { - /* No.. remove the current entry from the head of the list */ - - g_unloadhead = curr->flink; - } - - /* Nullify the forward link ... superstitious */ - - curr->flink = NULL; - } - - sched_unlock(); - return curr; -} - -/**************************************************************************** - * Name: unload_callback - * - * Description: - * If CONFIG_SCHED_HAVE_PARENT is defined, this function may be called to - * automatically unload the module when task exits. It assumes that - * bin was allocated with kmalloc() or friends and will also automatically - * free the structure with kfree() when the task exists. - * - * Input Parameter: - * pid - The ID of the task that just exited - * arg - A reference to the load structure cast to FAR void * - * - * Returned Value: - * None - * - ****************************************************************************/ - -static void unload_callback(int signo, siginfo_t *info, void *ucontext) -{ - FAR struct binary_s *bin; - int ret; - - /* Sanity checking */ - - if (!info || signo != SIGCHLD) - { - blldbg("ERROR:Bad signal callback: signo=%d info=%p\n", signo, callback); - return; - } - - /* Get the load information for this pid */ - - bin = unload_list_remove(info->si_pid); - if (!bin) - { - blldbg("ERROR: Could not find load info for PID=%d\n", info->si_pid); - return; - } - - /* Unload the module */ - - ret = unload_module(bin); - if (ret < 0) - { - blldbg("ERROR: unload_module failed: %d\n", get_errno()); - } - - /* Free the load structure */ - - kfree(bin); -} - -/**************************************************************************** - * Public Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: schedule_unload - * - * Description: - * If CONFIG_SCHED_HAVE_PARENT is defined, this function may be called by - * the parent of the the newly created task to automatically unload the - * module when the task exits. This assumes that (1) the caller is the - * parent of the created task, (2) that bin was allocated with kmalloc() - * or friends. It will also automatically free the structure with kfree() - * after unloading the module. - * - * Input Parameter: - * pid - The task ID of the child task - * bin - This structure must have been allocated with kmalloc() and must - * persist until the task unloads - * - * Returned Value: - * This is an end-user function, so it follows the normal convention: - * It returns 0 (OK) if the callback was successfully scheduled. On - * failure, it returns -1 (ERROR) and sets errno appropriately. - * - * On failures, the 'bin' structure will not be deallocated and the - * module not not be unloaded. - * - ****************************************************************************/ - -int schedule_unload(pid_t pid, FAR struct binary_s *bin) -{ - struct sigaction act; - struct sigaction oact; - sigset_t sigset; - irqstate_t flags; - int errorcode; - int ret; - - /* Make sure that SIGCHLD is unmasked */ - - (void)sigemptyset(&sigset); - (void)sigaddset(&sigset, SIGCHLD); - ret = sigprocmask(SIG_UNBLOCK, &sigset, NULL); - if (ret != OK) - { - /* The errno value will get trashed by the following debug output */ - - errorcode = get_errno(); - bvdbg("ERROR: sigprocmask failed: %d\n", ret); - goto errout; - } - - /* Add the structure to the list. We want to do this *before* connecting - * the signal handler. This does, however, make error recovery more - * complex if sigaction() fails below because then we have to remove the - * unload structure for the list in an unexpected context. - */ - - unload_list_add(pid, bin); - - /* Register the SIGCHLD handler */ - - act.sa_sigaction = unload_callback; - act.sa_flags = SA_SIGINFO; - - (void)sigfillset(&act.sa_mask); - (void)sigdelset(&act.sa_mask, SIGCHLD); - - ret = sigaction(SIGCHLD, &act, &oact); - if (ret != OK) - { - /* The errno value will get trashed by the following debug output */ - - errorcode = get_errno(); - bvdbg("ERROR: sigaction failed: %d\n" , ret); - - /* Emergency removal from the list */ - - flags = irqsave(); - if (unload_list_remove(pid) != bin) - { - blldbg("ERROR: Failed to remove structure\n"); - } - - goto errout; - } - - return OK; - -errout: - set_errno(errorcode); - return ERROR; -} - -#endif /* !CONFIG_BINFMT_DISABLE && CONFIG_SCHED_HAVE_PARENT */ - |