minimal plan9port to cross-build Jehanne

lib/lib9/post9p.c

@@ -0,0 +1,83 @@
+#include <u.h>
+#include <libc.h>
+
+int chattyfuse;
+
+int
+post9pservice(int fd, char *name, char *mtpt)
+{
+	int i, pid;
+	char *ns, *addr;
+	Waitmsg *w;
+
+	if(name == nil && mtpt == nil){
+		close(fd);
+		werrstr("nothing to do");
+		return -1;
+	}
+
+	if(name){
+		if(strchr(name, '!'))	/* assume is already network address */
+			addr = strdup(name);
+		else{
+			if((ns = getns()) == nil)
+				return -1;
+			addr = smprint("unix!%s/%s", ns, name);
+			free(ns);
+		}
+		if(addr == nil)
+			return -1;
+		switch(pid = fork()){
+		case -1:
+			return -1;
+		case 0:
+			dup(fd, 0);
+			dup(fd, 1);
+			for(i=3; i<20; i++)
+				close(i);
+			execlp("9pserve", "9pserve", "-u", addr, (char*)0);
+			fprint(2, "exec 9pserve: %r\n");
+			_exits("exec");
+		}
+		close(fd);
+		w = waitfor(pid);
+		if(w == nil)
+			return -1;
+		if(w->msg && w->msg[0]){
+			free(w);
+			werrstr("9pserve failed");
+			return -1;
+		}
+		free(w);
+		if(mtpt){
+			/* reopen */
+			if((fd = dial(addr, nil, nil, nil)) < 0){
+				werrstr("cannot reopen for mount: %r");
+				return -1;
+			}
+		}
+		free(addr);
+	}
+	if(mtpt){
+		switch(pid = rfork(RFFDG|RFPROC|RFNOWAIT)){
+		case -1:
+			return -1;
+		case 0:
+			dup(fd, 0);
+			for(i=3; i<20; i++)
+				close(i);
+
+			/* Try v9fs on Linux, which will mount 9P directly. */
+			execlp("mount9p", "mount9p", "-", mtpt, (char*)0);
+
+			if(chattyfuse)
+				execlp("9pfuse", "9pfuse", "-D", "-", mtpt, (char*)0);
+			else
+				execlp("9pfuse", "9pfuse", "-", mtpt, (char*)0);
+			fprint(2, "exec 9pfuse: %r\n");
+			_exits("exec");
+		}
+		close(fd);
+	}
+	return 0;
+}