Update the ESP32 network driver.

This PR updates the ESP32 network driver.

Changes include:

* Revision to driver to conform to contributing guidelines
* Update use of ESP IDF SDK to not use deprecated operations
* Add support for SNTP
* Add support for sntp_synchronized callback (thank you @pgoyout)
* Fix socket tests by using the same esp-idf API
* Updated docs and example program

Signed-off-by: Fred Dushin <[email protected]>

Author: fadushin

CHANGELOG.md

@@ -43,14 +43,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added support for serializing floats in erlang external term encoding
 - Added support for the `SMALL_BIG_EXT` erlang external term encoding
 - Added support for `erlang:memory(binary)`
-
+- Added support for callbacks on SNTP updates
 
 ### Fixed
 - Fixed issue with formatting integers with io:format() on STM32 platform
 - Fixed a bug in the order of child initialization in the `supervisor` module
 - Fixed a bug in the evaluation of `receive ... after infinity -> ...` expressions
 - Fixed a bug in when putting integers in bit syntax with integer field sizes
 - Fixed numerous bugs in memory allocations that could crash the VM
+- Fixed SNTP support that had been broken in IDF 4.x builds
 
 ### Breaking Changes
 

doc/src/network-programming-guide.md

@@ -194,11 +194,25 @@ In order to enable both STA and AP mode, simply provide valid configuration for
 
 You may configure the networking layer to automatically synchronize time on the ESP32 with an NTP server accessible on the network.
 
-To synchronize time with an NTP server, add a property list with the tag `sntp` at the top level configuration passed into the `network:start/1` function.  Specify the NTP hostname or IP address with which your device should sync using the `endpoint` property tag, e.g.,
+To synchronize time with an NTP server, add a property list with the tag `sntp` at the top level configuration passed into the `network:start/1` function.  Specify the NTP hostname or IP address with which your device should sync using the `host` property tag.  The `host` value can be a string or binary.
 
-    {sntp, [{endpoint, <<"pool.ntp.org">>}]}
+You can also specify a callback function that will get called when the clock is synchronized with the SNTP server via the `synchronized` property tag.  This function takes a tuple with the updated time in seconds and microseconds.
 
-The endpoint value can be a string or binary.
+For example:
+
+    %% erlang
+    {sntp, [
+        {host, <<"pool.ntp.org">>},
+        {synchronized, fun sntp_synchronized/1}
+    ]}
+
+where the `sntp_synchronized/1` function is defined as:
+
+    %% erlang
+    sntp_synchronized({TVSec, TVUsec}) ->
+        io:format("Synchronized time with SNTP server. TVSec=~p TVUsec=~p~n", [TVSec, TVUsec]).
+
+> Note. The device must be in STA mode and connected to an access point in order to use an SNTP server on your network or on the internet.
 
 ## NVS Credentials
 

doc/src/programmers-guide.md

@@ -1082,6 +1082,10 @@ For information about how to handle connections and disconnections from attached
 
 For information about how to run the AtomVM network in STA and AP mode simultaneously, see the [AtomVM Network Programming Guide](./network-programming-guide.md).
 
+#### SNTP
+
+For information about how to use SNTP to synchronize the clock on your device, see the [AtomVM Network Programming Guide](./network-programming-guide.md).
+
 ### UDP
 
 AtomVM supports network programming using the User Datagram Protocol (UDP) via the `gen_udp` module.  This modules obeys the syntax and semantics of the Erlang/OTP [`gen_udp`](https://erlang.org/doc/man/gen_udp.html) interface.

examples/erlang/esp32/ap_sta_network.erl

@@ -35,20 +35,24 @@ start() ->
             {ap_started, fun ap_started/0},
             {sta_connected, fun sta_connected/1},
             {sta_ip_assigned, fun sta_ip_assigned/1},
-            {sta_disconnected, fun sta_disconnected/1}
+            {sta_disconnected, fun sta_disconnected/1},
+            {ap_sta_ip_assigned, fun ap_sta_ip_assigned/1}
         ]},
         {sta, [
-            {ssid, esp:nvs_get_binary(atomvm, sta_ssid, <<"myssid">>)},
-            {psk, esp:nvs_get_binary(atomvm, sta_psk, <<"mypsk">>)},
+            {ssid, <<"myssid">>},
+            {psk, <<"mypsk">>},
             {connected, fun connected/0},
             {got_ip, fun got_ip/1},
             {disconnected, fun disconnected/0}
         ]},
-        {sntp, [{endpoint, "pool.ntp.org"}]}
+        {sntp, [
+            {host, "pool.ntp.org"},
+            {synchronized, fun sntp_synchronized/1}
+        ]}
     ],
     case network:start(Config) of
         {ok, _Pid} ->
-            sleep_forever();
+            timer:sleep(infinity);
         Error ->
             erlang:display(Error)
     end.
@@ -74,6 +78,8 @@ got_ip(IpInfo) ->
 disconnected() ->
     io:format("STA disconnected.~n").
 
-sleep_forever() ->
-    timer:sleep(10000),
-    sleep_forever().
+ap_sta_ip_assigned(Address) ->
+    io:format("AP assigned STA address ~p~n", [Address]).
+
+sntp_synchronized({TVSec, TVUsec}) ->
+    io:format("Synchronized time with SNTP server. TVSec=~p TVUsec=~p~n", [TVSec, TVUsec]).

libs/eavmlib/src/network.erl

@@ -98,7 +98,12 @@
     | ap_sta_ip_assigned_config().
 -type ap_config() :: {sta, [ap_config_property()]}.
 
--type sntp_config_property() :: {host, string() | binary()}.
+-type sntp_host_config() :: {host, string() | binary()}.
+-type sntp_synchronized_config() ::
+    {synchronized, fun(({non_neg_integer(), non_neg_integer()}) -> term())}.
+-type sntp_config_property() ::
+    sntp_host_config()
+    | sntp_synchronized_config().
 -type sntp_config() :: {sntp, [sntp_config_property()]}.
 
 -type network_config() :: [sta_config() | ap_config() | sntp_config()].
@@ -317,7 +322,11 @@ handle_info(
 ) ->
     maybe_ap_sta_ip_assigned_callback(Config, Address),
     {noreply, State};
-handle_info(_Msg, State) ->
+handle_info({Ref, {sntp_sync, TimeVal}} = _Msg, #state{ref = Ref, config = Config} = State) ->
+    maybe_sntp_sync_callback(Config, TimeVal),
+    {noreply, State};
+handle_info(Msg, State) ->
+    io:format("Received spurious message ~p~n", [Msg]),
     {noreply, State}.
 
 %% @hidden
@@ -352,12 +361,15 @@ get_driver_config(Config) ->
 
 %% @private
 maybe_add_nvs_entry(Key, List, NVSKey) ->
-    case {proplists:get_value(Key, List), esp:nvs_get_binary(atomvm, NVSKey)} of
-        {undefined, undefined} ->
-            List;
-        {undefined, NVSValue} ->
-            [{Key, NVSValue} | List];
-        {_Value, _} ->
+    case proplists:get_value(Key, List) of
+        undefined ->
+            case esp:nvs_get_binary(atomvm, NVSKey) of
+                undefined ->
+                    List;
+                NVSValue ->
+                    [{Key, NVSValue} | List]
+            end;
+        _Value ->
             List
     end.
 
@@ -389,6 +401,10 @@ maybe_ap_sta_disconnected_callback(Config, Mac) ->
 maybe_ap_sta_ip_assigned_callback(Config, Address) ->
     maybe_callback1({sta_ip_assigned, Address}, proplists:get_value(ap, Config)).
 
+%% @private
+maybe_sntp_sync_callback(Config, TimeVal) ->
+    maybe_callback1({synchronized, TimeVal}, proplists:get_value(sntp, Config)).
+
 %% @private
 maybe_callback0(_Key, undefined) ->
     ok;

src/libAtomVM/term.h

@@ -86,6 +86,19 @@ extern "C" {
 #define TUPLE_SIZE(elems) ((int) (elems + 1))
 #define REFC_BINARY_CONS_OFFET 4
 
+#define TERM_BINARY_SIZE_IS_HEAP(size) ((size) < REFC_BINARY_MIN)
+
+#if TERM_BYTES == 4
+#define TERM_BINARY_DATA_SIZE_IN_TERMS(size) \
+    (TERM_BINARY_SIZE_IS_HEAP(size) ? (((size) + 4 - 1) >> 2) + 1 : TERM_BOXED_REFC_BINARY_SIZE)
+#elif TERM_BYTES == 8
+#define TERM_BINARY_DATA_SIZE_IN_TERMS(size) \
+    (TERM_BINARY_SIZE_IS_HEAP(size) ? (((size) + 8 - 1) >> 3) + 1 : TERM_BOXED_REFC_BINARY_SIZE)
+#endif
+
+#define TERM_BINARY_HEAP_SIZE(size) \
+    (TERM_BINARY_DATA_SIZE_IN_TERMS(size) + BINARY_HEADER_SIZE)
+
 #define TERM_DEBUG_ASSERT(...)
 
 #define TERM_FROM_ATOM_INDEX(atom_index) ((atom_index << 6) | 0xB)