added exit() to stdlib

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@1611 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/kernel/Jamfile

@@ -255,6 +255,7 @@ KernelStaticLibraryObjects libc.a :
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>atoi.o
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>bsearch.o
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>env.o
+	<$(SOURCE_GRIST)!libroot!posix!stdlib>exit.o
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>heapsort.o
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>merge.o
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>multibyte.o
@@ -399,6 +400,7 @@ KernelLd libroot.so :
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>atoi.o
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>bsearch.o
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>env.o
+	<$(SOURCE_GRIST)!libroot!posix!stdlib>exit.o
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>heapsort.o
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>merge.o
 	<$(SOURCE_GRIST)!libroot!posix!stdlib>multibyte.o

src/kernel/libroot/posix/stdlib/Jamfile

@@ -5,6 +5,7 @@ KernelObjects
 	<$(SOURCE_GRIST)>atoi.c 
 	<$(SOURCE_GRIST)>bsearch.c
 	<$(SOURCE_GRIST)>env.c
+	<$(SOURCE_GRIST)>exit.c
 	<$(SOURCE_GRIST)>heapsort.c 
 	<$(SOURCE_GRIST)>merge.c
 	<$(SOURCE_GRIST)>multibyte.c 

src/kernel/libroot/posix/stdlib/exit.c

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2002, OpenBeOS Project
+ *
+ * This file is part of the OpenBeOS system interface.
+ * It is distributed under the terms of the OpenBeOS license.
+ *
+ *
+ * Author(s):
+ * Daniel Reinhold (danielre@users.sf.net)
+ *
+ */
+
+#include <syscalls.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+// ToDo: move this puppy to a more standard location
+#include "../stdio/local.h"
+
+// ToDo: this is supposed to be declared in <stdlib.h>
+int  atexit(void (*func)(void));
+
+
+
+#define _EXIT_STACK_SIZE_ 32
+
+static void (*_Exit_Stack[_EXIT_STACK_SIZE_])(void) = {0};
+static int    _Exit_SP = 0;
+
+
+int
+atexit(void (*func)(void))
+{
+	// push the function pointer onto the exit stack
+	
+	if (_Exit_SP < _EXIT_STACK_SIZE_) {
+		_Exit_Stack[_Exit_SP++] = func;
+		return 0;
+	}
+	
+	return -1;
+}
+
+
+void
+exit(int status)
+{	
+	// unwind the exit stack, calling the registered functions
+	while (_Exit_SP > 0)
+		(*_Exit_Stack[--_Exit_SP])();
+	
+	// close all open files
+	(*__cleanup)();
+	
+	// exit with status code
+	sys_exit(status);
+}