122 lines
2.7 KiB
C
122 lines
2.7 KiB
C
/*
|
|
* SPDX-FileCopyrightText: 2008 - 2011, Nicolas François
|
|
*
|
|
* SPDX-License-Identifier: BSD-3-Clause
|
|
*/
|
|
|
|
#include <config.h>
|
|
|
|
#include <assert.h>
|
|
#include <stdio.h>
|
|
|
|
#include "prototypes.h"
|
|
|
|
/*
|
|
* The cleanup_functions stack.
|
|
*/
|
|
#define CLEANUP_FUNCTIONS 10
|
|
|
|
typedef /*@null@*/void * parg_t;
|
|
|
|
static cleanup_function cleanup_functions[CLEANUP_FUNCTIONS];
|
|
static parg_t cleanup_function_args[CLEANUP_FUNCTIONS];
|
|
static pid_t cleanup_pid = 0;
|
|
|
|
/*
|
|
* - Cleanup functions shall not fail.
|
|
* - You should register do_cleanups with atexit.
|
|
* - You should add cleanup functions to the stack with add_cleanup when
|
|
* an operation is expected to be executed later, and remove it from the
|
|
* stack with del_cleanup when it has been executed.
|
|
*
|
|
**/
|
|
|
|
/*
|
|
* do_cleanups - perform the actions stored in the cleanup_functions stack.
|
|
*
|
|
* Cleanup action are not executed on exit of the processes started by the
|
|
* parent (first caller of add_cleanup).
|
|
*
|
|
* It is intended to be used as:
|
|
* atexit (do_cleanups);
|
|
*/
|
|
void do_cleanups (void)
|
|
{
|
|
unsigned int i;
|
|
|
|
/* Make sure there were no overflow */
|
|
assert (NULL == cleanup_functions[CLEANUP_FUNCTIONS-1]);
|
|
|
|
if (getpid () != cleanup_pid) {
|
|
return;
|
|
}
|
|
|
|
i = CLEANUP_FUNCTIONS;
|
|
do {
|
|
i--;
|
|
if (cleanup_functions[i] != NULL) {
|
|
cleanup_functions[i] (cleanup_function_args[i]);
|
|
}
|
|
} while (i>0);
|
|
}
|
|
|
|
/*
|
|
* add_cleanup - Add a cleanup_function to the cleanup_functions stack.
|
|
*/
|
|
void add_cleanup (/*@notnull@*/cleanup_function pcf, /*@null@*/void *arg)
|
|
{
|
|
unsigned int i;
|
|
assert (NULL != pcf);
|
|
|
|
assert (NULL == cleanup_functions[CLEANUP_FUNCTIONS-2]);
|
|
|
|
if (0 == cleanup_pid) {
|
|
cleanup_pid = getpid ();
|
|
}
|
|
|
|
/* Add the cleanup_function at the end of the stack */
|
|
for (i=0; NULL != cleanup_functions[i]; i++);
|
|
cleanup_functions[i] = pcf;
|
|
cleanup_function_args[i] = arg;
|
|
}
|
|
|
|
/*
|
|
* del_cleanup - Remove a cleanup_function from the cleanup_functions stack.
|
|
*/
|
|
void del_cleanup (/*@notnull@*/cleanup_function pcf)
|
|
{
|
|
unsigned int i;
|
|
assert (NULL != pcf);
|
|
|
|
/* Find the pcf cleanup function */
|
|
for (i=0; i<CLEANUP_FUNCTIONS; i++) {
|
|
if (cleanup_functions[i] == pcf) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Make sure the cleanup function was found */
|
|
assert (i<CLEANUP_FUNCTIONS);
|
|
|
|
/* Move the rest of the cleanup functions */
|
|
for (; i<CLEANUP_FUNCTIONS; i++) {
|
|
/* Make sure the cleanup function was specified only once */
|
|
assert ( (i == (CLEANUP_FUNCTIONS -1))
|
|
|| (cleanup_functions[i+1] != pcf));
|
|
|
|
if (i == (CLEANUP_FUNCTIONS -1)) {
|
|
cleanup_functions[i] = NULL;
|
|
cleanup_function_args[i] = NULL;
|
|
} else {
|
|
cleanup_functions[i] = cleanup_functions[i+1];
|
|
cleanup_function_args[i] = cleanup_function_args[i+1];
|
|
}
|
|
|
|
/* A NULL indicates the end of the stack */
|
|
if (NULL == cleanup_functions[i]) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|