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Diffstat (limited to 'nuttx/sched/on_exit.c')
| -rw-r--r-- | nuttx/sched/on_exit.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/nuttx/sched/on_exit.c b/nuttx/sched/on_exit.c new file mode 100644 index 000000000..5b8be5cd1 --- /dev/null +++ b/nuttx/sched/on_exit.c @@ -0,0 +1,171 @@ +/**************************************************************************** + * sched/on_exit.c + * + * Copyright (C) 2012 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 <stdlib.h> +#include <assert.h> +#include <unistd.h> +#include <debug.h> +#include <errno.h> + +#include <nuttx/fs/fs.h> + +#include "os_internal.h" + +#ifdef CONFIG_SCHED_ONEXIT + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Type Declarations + ****************************************************************************/ + +/**************************************************************************** + * Global Variables + ****************************************************************************/ + +/**************************************************************************** + * Private Variables + ****************************************************************************/ + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: on_exit + * + * Description: + * Registers a function to be called at program exit. + * The on_exit() function registers the given function to be called + * at normal process termination, whether via exit or via return from + * the program's main(). The function is passed the status argument + * given to the last call to exit and the arg argument from on_exit(). + * + * NOTE 1: This function comes from SunOS 4, but is also present in + * libc4, libc5 and glibc. It no longer occurs in Solaris (SunOS 5). + * Avoid this function, and use the standard atexit() instead. + * + * NOTE 2: CONFIG_SCHED_ONEXIT must be defined to enable this function + * + * Limitiations in the current implementation: + * + * 1. Only a single on_exit function can be registered unless + * CONFIG_SCHED_ONEXIT_MAX defines a larger number. + * 2. on_exit functions are not inherited when a new task is + * created. + * + * Parameters: + * func - A pointer to the function to be called when the task exits. + * arg - An argument that will be provided to the on_exit() function when + * the task exits. + * + * Return Value: + * Zero on success. Non-zero on failure. + * + ****************************************************************************/ + +int on_exit(CODE void (*func)(int, FAR void *), FAR void *arg) +{ +#if defined(CONFIG_SCHED_ONEXIT_MAX) && CONFIG_SCHED_ONEXIT_MAX > 1 + _TCB *tcb = (_TCB*)g_readytorun.head; + int index; + int ret = ERROR; + + /* The following must be atomic */ + + if (func) + { + sched_lock(); + + /* Search for the first available slot. on_exit() functions are registered + * from lower to higher arry indices; they must be called in the reverse + * order of registration when task exists, i.e., from higher to lower + * indices. + */ + + available = -1; + for (index = 0; index < CONFIG_SCHED_ONEXIT_MAX; index++) + { + if (!tcb->onexitfunc[index]) + { + tcb->onexitfunc[index] = func; + tcb->onexitarg[index] = arg; + ret = OK; + break; + } + } + + sched_unlock(); + } + + return ret; +#else + _TCB *tcb = (_TCB*)g_readytorun.head; + int ret = ERROR; + + /* The following must be atomic */ + + sched_lock(); + if (func && !tcb->onexitfunc) + { + tcb->onexitfunc = func; + tcb->onexitarg = arg; + ret = OK; + } + + sched_unlock(); + return ret; +#endif +} + +#endif /* CONFIG_SCHED_ONEXIT */ + + |