Add new osmo_fd_get_by_fd() function

This function can be used to obtain the osmo_fd corresponding to a given
fd.  The latter can be useful when integrating libosmocore main loop
with other libraries.

2 files changed, 14 insertions, 0 deletions

diff --git a/include/osmocom/core/select.h b/include/osmocom/core/select.h
index b6b9e821..b9e3b51a 100644
--- a/include/osmocom/core/select.h
+++ b/include/osmocom/core/select.h
@@ -39,4 +39,6 @@ int osmo_fd_register(struct osmo_fd *fd);
 void osmo_fd_unregister(struct osmo_fd *fd);
 int osmo_select_main(int polling);
 
+struct osmo_fd *osmo_fd_get_by_fd(int fd);
+
 /*! @} */
diff --git a/src/select.c b/src/select.c
index 5421c773..477ff662 100644
--- a/src/select.c
+++ b/src/select.c
@@ -170,6 +170,18 @@ restart:
 	return work;
 }
 
+/*! \brief find an osmo_fd based on the integer fd */
+struct osmo_fd *osmo_fd_get_by_fd(int fd)
+{
+	struct osmo_fd *ofd;
+
+	llist_for_each_entry(ofd, &osmo_fds, list) {
+		if (ofd->fd == fd)
+			return ofd;
+	}
+	return NULL;
+}
+
 /*! @} */
 
 #endif /* _HAVE_SYS_SELECT_H */