Libc-391.4.1.tar.gz

[apple/libc.git] / stdlib / FreeBSD / atexit.c

diff --git a/stdlib/FreeBSD/atexit.c b/stdlib/FreeBSD/atexit.c
index 51b195bfc5c8c5ccb701b3c06ae3c70fd3bea4f6..bd94bcd7230d91f3e5fe39850f64d02b78dd3576 100644 (file)
--- a/stdlib/FreeBSD/atexit.c
+++ b/stdlib/FreeBSD/atexit.c
@@ -38,7 +38,7 @@
 static char sccsid[] = "@(#)atexit.c   8.2 (Berkeley) 7/3/94";
 #endif /* LIBC_SCCS and not lint */
 #include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libc/stdlib/atexit.c,v 1.6 2002/03/22 21:53:09 obrien Exp $");
+__FBSDID("$FreeBSD: src/lib/libc/stdlib/atexit.c,v 1.7 2003/12/19 17:11:20 kan Exp $");
 
 #include "namespace.h"
 #include <stddef.h>
@@ -50,19 +50,38 @@ __FBSDID("$FreeBSD: src/lib/libc/stdlib/atexit.c,v 1.6 2002/03/22 21:53:09 obrie
 
 #include "libc_private.h"
 
+#define        ATEXIT_FN_EMPTY 0
+#define        ATEXIT_FN_STD   1
+#define        ATEXIT_FN_CXA   2
+
 static pthread_mutex_t atexit_mutex = PTHREAD_MUTEX_INITIALIZER;
 
 #define _MUTEX_LOCK(x)         if (__isthreaded) _pthread_mutex_lock(x)
 #define _MUTEX_UNLOCK(x)       if (__isthreaded) _pthread_mutex_unlock(x)
 
-struct atexit *__atexit;       /* points to head of LIFO stack */
+struct atexit {
+       struct atexit *next;                    /* next in list */
+       int ind;                                /* next index in this table */
+       struct atexit_fn {
+               int fn_type;                    /* ATEXIT_? from above */
+               union {
+                       void (*std_func)(void);
+                       void (*cxa_func)(void *);
+               } fn_ptr;                       /* function pointer */
+               void *fn_arg;                   /* argument for CXA callback */
+               void *fn_dso;                   /* shared module handle */
+       } fns[ATEXIT_SIZE];                     /* the table itself */
+};
+
+static struct atexit *__atexit;                /* points to head of LIFO stack */
 
 /*
- * Register a function to be performed at exit.
+ * Register the function described by 'fptr' to be called at application
+ * exit or owning shared object unload time. This is a helper function
+ * for atexit and __cxa_atexit.
  */
-int
-atexit(fn)
-       void (*fn)();
+static int
+atexit_register(struct atexit_fn *fptr)
 {
        static struct atexit __atexit0; /* one guaranteed table */
        struct atexit *p;
@@ -89,7 +108,82 @@ atexit(fn)
                p->next = __atexit;
                __atexit = p;
        }
-       p->fns[p->ind++] = fn;
+       p->fns[p->ind++] = *fptr;
+       _MUTEX_UNLOCK(&atexit_mutex);
+       return 0;
+}
+
+/*
+ * Register a function to be performed at exit.
+ */
+int
+atexit(void (*func)(void))
+{
+       struct atexit_fn fn;
+       int error;
+
+       fn.fn_type = ATEXIT_FN_STD;
+       fn.fn_ptr.std_func = func;;
+       fn.fn_arg = NULL;
+       fn.fn_dso = NULL;
+
+       error = atexit_register(&fn);   
+       return (error);
+}
+
+/*
+ * Register a function to be performed at exit or when an shared object
+ * with given dso handle is unloaded dynamically.
+ */
+int
+__cxa_atexit(void (*func)(void *), void *arg, void *dso)
+{
+       struct atexit_fn fn;
+       int error;
+
+       fn.fn_type = ATEXIT_FN_CXA;
+       fn.fn_ptr.cxa_func = func;;
+       fn.fn_arg = arg;
+       fn.fn_dso = dso;
+
+       error = atexit_register(&fn);   
+       return (error);
+}
+
+/*
+ * Call all handlers registered with __cxa_atexit for the shared
+ * object owning 'dso'.  Note: if 'dso' is NULL, then all remaining
+ * handlers are called.
+ */
+void
+__cxa_finalize(void *dso)
+{
+       struct atexit *p;
+       struct atexit_fn fn;
+       int n;
+
+       _MUTEX_LOCK(&atexit_mutex);
+       for (p = __atexit; p; p = p->next) {
+               for (n = p->ind; --n >= 0;) {
+                       if (p->fns[n].fn_type == ATEXIT_FN_EMPTY)
+                               continue; /* already been called */
+                       if (dso != NULL && dso != p->fns[n].fn_dso)
+                               continue; /* wrong DSO */
+                       fn = p->fns[n];
+                       /*
+                         Mark entry to indicate that this particular handler
+                         has already been called.
+                       */
+                       p->fns[n].fn_type = ATEXIT_FN_EMPTY;
+                       _MUTEX_UNLOCK(&atexit_mutex);
+               
+                       /* Call the function of correct type. */
+                       if (fn.fn_type == ATEXIT_FN_CXA)
+                               fn.fn_ptr.cxa_func(fn.fn_arg);
+                       else if (fn.fn_type == ATEXIT_FN_STD)
+                               fn.fn_ptr.std_func();
+                       _MUTEX_LOCK(&atexit_mutex);
+               }
+       }
        _MUTEX_UNLOCK(&atexit_mutex);
-       return (0);
 }