(lwpProc, lwpSem): Declare as incomplete type in include/lwp.h. Move

complete declaration to src/lib/lwp/lwpint.h.
(lwpQueue): Move to src/lib/lwp/lwpint.h.
(empth_main, empth_flags): New.
(empth_init): Initialize them.
(empth_create, empth_exit): Use them instead of lwpProc members.

include/lwp.h

@@ -32,43 +32,8 @@
 #define LWP_STACKCHECK	0x1
 #define LWP_PRINT	0x2
 
-/* process control block.  do *not* change the position of context */
-struct lwpProc {
-#ifdef UCONTEXT
-    ucontext_t context;		/* context structure */
-#else  /* !UCONTEXT */
-    jmp_buf context;		/* processor context area */
-#endif /* !UCONTEXT */
-    void *sbtm;			/* bottom of stack attached to it */
-    int size;			/* size of stack */
-    void (*entry)(void *);	/* entry point */
-    int dead;			/* whether the process can be rescheduled */
-    int pri;			/* which scheduling queue we're on */
-    long runtime;		/* time at which process is restarted */
-    int fd;			/* fd we're blocking on */
-    int argc;			/* initial arguments */
-    char **argv;
-    void *ud;			/* user data */
-    void *lowmark;		/* start of low buffer around stack */
-    void *himark;		/* start of upper buffer around stack */
-    char *name;			/* process name and description */
-    char *desc;
-    int flags;
-    struct lwpProc *next;
-};
-
-/* queue */
-struct lwpQueue {
-    struct lwpProc *head;
-    struct lwpProc *tail;
-};
-
-/* semaphore */
-struct lwpSem {
-    int count;
-    struct lwpQueue q;
-    char *name;
-};
+struct lwpProc;
+struct lwpSem;
 
 #define LWP_FD_READ	0x1
 #define LWP_FD_WRITE	0x2