Little fixes.

src/lib9/ffork-Linux.c

@@ -1,18 +1,41 @@
+#include <u.h>
 #include <sched.h>
 #include <signal.h>
-#include <lib9.h>
+#include <libc.h>
+#include "9proc.h"
 
 int fforkstacksize = 16384;
 
+static int
+tramp(void *v)
+{
+	void (*fn)(void*), *arg;
+	void **v2;
+
+	_p9uproc(0);
+	v2 = v;
+	fn = v2[0];
+	arg = v2[1];
+	free(v2);
+	fn(arg);
+	return 0;
+}
+	
 int
 ffork(int flags, void (*fn)(void*), void *arg)
 {
+	void **v;
 	char *p;
 	int cloneflag, pid;
 
+	_p9uproc(0);
 	p = malloc(fforkstacksize);
-	if(p == nil)
+	v = malloc(sizeof(void*)*2);
+	if(p==nil || v==nil){
+		free(p);
+		free(v);
 		return -1;
+	}
 	cloneflag = 0;
 	flags &= ~RFPROC;
 	if(flags&RFMEM){
@@ -29,9 +52,13 @@ ffork(int flags, void (*fn)(void*), void *arg)
 		flags &= ~RFNOWAIT;
 	if(flags){
 		fprint(2, "unknown rfork flags %x\n", flags);
+		free(p);
+		free(v);
 		return -1;
 	}
-	pid = clone((int(*)(void*))fn, p+fforkstacksize-16, cloneflag, arg);
+	v[0] = fn;
+	v[1] = arg;
+	pid = clone(tramp, p+fforkstacksize-16, cloneflag, v);
 	if(pid < 0)
 		free(p);
 	return pid;