Decouple the signalling into a struct IOMuxSignaller

src/iomux_waker.c

@@ -6,7 +6,7 @@
 
 static void uc_waker_pipe_cb(struct IOMux *mux, struct IOMuxFD *fd, unsigned int event)
 {
-    char buf[259];
+    char buf[256];
     struct IOMuxWaker *wk;
     int rc;
 
@@ -32,13 +32,13 @@ static void uc_waker_pipe_cb(struct IOMux *mux, struct IOMuxFD *fd, unsigned int
     wk->wake_cb(wk);
 }
 
-static int uc_install_wake_handler(struct IOMuxWaker *wk)
+static int uc_install_wake_handler(struct IOMuxWaker *wk, int rfd)
 {
     struct IOMuxFD *fd = &wk->read_fd;
 
     memset(fd, 0, sizeof *fd);
 
-    fd->fd = wk->fds[0];
+    fd->fd = rfd;
     fd->callback = uc_waker_pipe_cb;
     fd->cookie_ptr = wk;
     fd->what = MUX_EV_READ;
@@ -49,28 +49,30 @@ static int uc_install_wake_handler(struct IOMuxWaker *wk)
 int uc_iomux_waker_init(struct IOMux *mux, struct IOMuxWaker *wk, uc_waker_cb cb)
 {
     int rc;
+    int pfds[2];
 
     assert(wk != NULL);
     assert(cb != NULL);
 
     memset(wk, 0 , sizeof *wk);
 
-    rc = pipe(wk->fds);
+    rc = pipe(pfds);
     if (rc != 0) {
         return errno;
     }
     
     wk->mux = mux;
     wk->wake_cb = cb;
+    wk->signaller.fd = pfds[1];
 
-    if (uc_install_wake_handler(wk) == 0) {
+    if (uc_install_wake_handler(wk, pfds[0]) == 0) {
         return 0;
     } else {
         int saved_errno;
 
         saved_errno = errno;
-        close(wk->fds[0]);
-        close(wk->fds[1]);
+        close(pfds[0]);
+        close(pfds[1]);
 
         return saved_errno;
     }
@@ -82,30 +84,30 @@ int uc_iomux_waker_destroy(struct IOMuxWaker *wk)
 
     assert(wk != NULL);
 
-    close(wk->fds[0]);
-    close(wk->fds[1]);
-
     rc = iomux_unregister_fd(wk->mux, &wk->read_fd);
     assert(rc == 0);
 
+    close(wk->signaller.fd);
+    close(wk->read_fd.fd);
+
     wk->mux = NULL;
     wk->wake_cb = NULL;
-    wk->fds[0] = wk->fds[1] = -1;
+    wk->signaller.fd = -1;
 
     assert(rc == 0);
 
     return rc;
 }
 
-int uc_iomux_waker_signal(struct IOMuxWaker *wk)
+int uc_iomux_waker_signal(struct IOMuxSignaller *signaller)
 {
     int rc;
     static const char x = 'X';
 
-    assert(wk != NULL);
+    assert(signaller != NULL);
 
     do {
-        rc = write(wk->fds[1], &x, 1);
+        rc = write(signaller->fd, &x, 1);
     } while (rc == -1 && errno == EINTR);
 
     //if we would have blocked, the pipe is already