extmod/modnetwork: Forward if.config(hostname) to network.hostname.

This removes the duplicate code in cyw43, esp32, esp8266 that implements
the same logic as network.hostname.

Renames the `mod_network_hostname` (where we store the hostname value in
`.data`) to `mod_network_hostname_data` to make way for calling the shared
function `mod_network_hostname`.

And uses memcpy for mod_network_hostname_data, because the length of source
is already known and removes reliance on string data being null-terminated.

This work was funded through GitHub Sponsors.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/extmod/modnetwork.h b/extmod/modnetwork.h
index e9769e309..e3239c2a0 100644
--- a/extmod/modnetwork.h
+++ b/extmod/modnetwork.h
@@ -61,7 +61,12 @@ extern char mod_network_country_code[2];
 #endif
 
 // This is a null-terminated string.
-extern char mod_network_hostname[MICROPY_PY_NETWORK_HOSTNAME_MAX_LEN + 1];
+extern char mod_network_hostname_data[MICROPY_PY_NETWORK_HOSTNAME_MAX_LEN + 1];
+
+// To support backwards-compatible (esp32, esp8266, cyw43)
+// `if.config(hostname=...)` to forward directly to the implementation of
+// `network.hostname(...)`.
+mp_obj_t mod_network_hostname(size_t n_args, const mp_obj_t *args);
 
 #if MICROPY_PY_LWIP
 struct netif;