libc: move exits to its own translation unit (another good idea from 9front)

sys/src/lib/c/build.json

@@ -139,6 +139,7 @@
 			"port/ctype.c",
 			"port/encodefmt.c",
 			"port/execl.c",
+			"port/exits.c",
 			"port/exp.c",
 			"port/fabs.c",
 			"port/floor.c",

sys/src/lib/c/port/atexit.c

@@ -10,6 +10,8 @@
 #include <u.h>
 #include <libc.h>
 
+extern void (*_jehanne_onexit)(void);
+
 #define	NEXIT	33
 
 typedef struct Onex Onex;
@@ -21,11 +23,26 @@ struct Onex{
 static Lock onexlock;
 Onex onex[NEXIT];
 
+static void
+onexit(void)
+{
+	int i, pid;
+	void (*f)(void);
+
+	pid = jehanne_getpid();
+	for(i = nelem(onex)-1; i >= 0; i--)
+		if((f = onex[i].f) != nil && onex[i].pid == pid) {
+			onex[i].f = nil;
+			(*f)();
+		}
+}
+
 int
 jehanne_atexit(void (*f)(void))
 {
 	int i;
 
+	_jehanne_onexit = onexit;
 	jehanne_lock(&onexlock);
 	for(i=0; i<NEXIT; i++)
 		if(onex[i].f == 0) {
@@ -48,25 +65,3 @@ jehanne_atexitdont(void (*f)(void))
 		if(onex[i].f == f && onex[i].pid == pid)
 			onex[i].f = 0;
 }
-
-#pragma profile off
-
-void
-jehanne_exits(const char *s)
-{
-	void _fini(void);
-	int i, pid;
-	void (*f)(void);
-
-	pid = jehanne_getpid();
-	for(i = NEXIT-1; i >= 0; i--)
-		if((f = onex[i].f) && pid == onex[i].pid) {
-			onex[i].f = 0;
-			(*f)();
-		}
-	_fini();
-	_exits(s);
-	__builtin_unreachable();
-}
-
-#pragma profile on

sys/src/lib/c/port/exits.c

@@ -0,0 +1,25 @@
+/*
+ * This file is part of the UCB release of Plan 9. It is subject to the license
+ * terms in the LICENSE file found in the top-level directory of this
+ * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
+ * part of the UCB release of Plan 9, including this file, may be copied,
+ * modified, propagated, or distributed except according to the terms contained
+ * in the LICENSE file.
+ */
+
+#include <u.h>
+#include <libc.h>
+
+void (*_jehanne_onexit)(void);
+
+void
+jehanne_exits(const char *s)
+{
+	void _fini(void);
+
+	if(_jehanne_onexit != nil)
+		(*_jehanne_onexit)();
+	_fini();
+	_exits(s);
+	__builtin_unreachable();
+}