GATTC write support

Author: rojer

include/mgos_bt_gattc.h

@@ -34,6 +34,7 @@ enum mgos_bt_gattc_event {
   MGOS_BT_GATTC_EV_DISCOVERY_RESULT, /* mgos_bt_gattc_discovery_result_arg */
   MGOS_BT_GATTC_EV_DISCOVERY_DONE,   /* mgos_bt_gattc_discovery_done_arg */
   MGOS_BT_GATTC_EV_READ_RESULT,      /* mgos_bt_gattc_read_result_arg */
+  MGOS_BT_GATTC_EV_WRITE_RESULT,     /* mgos_bt_gattc_write_result_arg */
   MGOS_BT_GATTC_EV_NOTIFY,           /* mgos_bt_gattc_notify_arg */
 };
 
@@ -59,6 +60,12 @@ struct mgos_bt_gattc_read_result_arg {
   struct mg_str data;            /* Data that has been read */
 };
 
+struct mgos_bt_gattc_write_result_arg {
+  struct mgos_bt_gatt_conn conn; /* Device address */
+  uint16_t handle;               /* Characteristic handle  */
+  bool ok;                       /* Success indicator. */
+};
+
 struct mgos_bt_gattc_notify_arg {
   struct mgos_bt_gatt_conn conn; /* Device address */
   uint16_t handle;               /* Characteristic handle  */

mjs_fs/api_bt_gattc.js

@@ -13,25 +13,30 @@ let GATTC = {
   read: ffi('bool mgos_bt_gattc_read(int, int)'),
   getReadResult: function(evdata) { return s2o(evdata, GATTC._rrd); },
 
+  write: function(c, h, data, resp_required) {
+    return GATTC._write(c, h, data, !!resp_required);
+  },
+  getWriteResult: function(evdata) { return s2o(evdata, GATTC._wrd); },
+
   // NB: does not work at present, TODO
   subscribe: ffi('bool mgos_bt_gattc_subscribe(int, int)'),
   getNotifyArg: function(evdata) { return s2o(evdata, GATTC._nad); },
 
-  // NB: does not work at present, TODO
-  write: ffi('bool mgos_bt_gattc_write_js(int, int, struct mg_str *)'),
-
   disconnect: ffi('bool mgos_bt_gattc_disconnect(int)'),
 
   _cd: ffi('void *mgos_bt_gatt_js_get_conn_def(void)')(),
   _rrd: ffi('void *mgos_bt_gattc_js_get_read_result_def(void)')(),
+  _wrd: ffi('void *mgos_bt_gattc_js_get_write_result_def(void)')(),
   _nad: ffi('void *mgos_bt_gattc_js_get_notify_arg_def(void)')(),
   _drad: ffi('void *mgos_bt_gattc_js_get_discovery_result_arg_def(void)')(),
   _ddad: ffi('void *mgos_bt_gattc_js_get_discovery_done_arg_def(void)')(),
+  _write: ffi('bool mgos_bt_gattc_write_js(int, int, struct mg_str *, bool)'),
 };
 
 GATTC.EV_CONNECT = GATTC.EV_GRP + 0;
 GATTC.EV_DISCONNECT = GATTC.EV_GRP + 1;
 GATTC.EV_DISCOVERY_RESULT = GATTC.EV_GRP + 2;
 GATTC.EV_DISCOVERY_DONE = GATTC.EV_GRP + 3;
 GATTC.EV_READ_RESULT = GATTC.EV_GRP + 4;
-GATTC.EV_NOTIFY = GATTC.EV_GRP + 5;
+GATTC.EV_WRITE_RESULT = GATTC.EV_GRP + 5;
+GATTC.EV_NOTIFY = GATTC.EV_GRP + 6;

src/esp32/esp32_bt_gattc.c

@@ -258,6 +258,7 @@ static int esp32_bt_gattc_read_cb(uint16_t conn_id,
 
 bool mgos_bt_gattc_read(uint16_t conn_id, uint16_t handle) {
   LOG(LL_DEBUG, ("READ c %d ah %d", conn_id, handle));
+  int ret;
   bool res = false;
   esp32_bt_rlock();
   struct esp32_bt_gattc_conn *conn = find_conn_by_id(conn_id);
@@ -275,11 +276,12 @@ bool mgos_bt_gattc_read(uint16_t conn_id, uint16_t handle) {
   pr->conn = conn;
   pr->handle = handle;
   mbuf_init(&pr->data, 0);
-  if (ble_gattc_read_long(conn_id, handle, 0, esp32_bt_gattc_read_cb, pr) ==
-      0) {
+  ret = ble_gattc_read_long(conn_id, handle, 0, esp32_bt_gattc_read_cb, pr);
+  if (ret == 0) {
     SLIST_INSERT_HEAD(&conn->pending_reads, pr, next);
     res = true;
   } else {
+    LOG(LL_ERROR, ("ret = %d", ret));
     esp32_bt_gattc_pending_read_free(pr);
   }
 out:
@@ -293,11 +295,49 @@ bool mgos_bt_gattc_subscribe(uint16_t conn_id, uint16_t handle) {
   return false;
 }
 
+static int esp32_bt_gattc_write_cb(uint16_t conn_id,
+                                   const struct ble_gatt_error *err,
+                                   struct ble_gatt_attr *attr, void *arg) {
+  bool resp_required = (bool) (uintptr_t) arg;
+  LOG(LL_DEBUG, ("WRITE_CB c %d err %p st %d attr %p ah %d rr %d", conn_id, err,
+                 (err ? err->status : -1), attr, (attr ? attr->handle : 0),
+                 resp_required));
+  struct esp32_bt_gattc_conn *conn = find_conn_by_id(conn_id);
+  if (conn == NULL) return BLE_ATT_ERR_UNLIKELY;
+  if (resp_required) {
+    struct mgos_bt_gattc_write_result_arg rarg = {
+        .conn = conn->gc,
+        .handle = attr->handle,
+        .ok = (err->status == 0),
+    };
+    mgos_event_trigger(MGOS_BT_GATTC_EV_WRITE_RESULT, &rarg);
+  }
+  return 0;
+}
+
 bool mgos_bt_gattc_write(uint16_t conn_id, uint16_t handle, struct mg_str data,
                          bool resp_required) {
+  LOG(LL_DEBUG, ("WRITE c %d ah %d rr %d", conn_id, handle, resp_required));
   struct esp32_bt_gattc_conn *conn = find_conn_by_id(conn_id);
   if (conn == NULL) return false;
-  return false;
+  int ret;
+  uint16_t mtu = ble_att_mtu(conn_id);
+  if (data.len < mtu - 1) {
+    if (resp_required) {
+      ret = ble_gattc_write_flat(conn_id, handle, data.p, data.len,
+                                 esp32_bt_gattc_write_cb, (void *) 1);
+    } else {
+      ret = ble_gattc_write_no_rsp_flat(conn_id, handle, data.p, data.len);
+    }
+  } else {
+    struct os_mbuf *om = ble_hs_mbuf_from_flat(data.p, data.len);
+    ret = ble_gattc_write_long(conn_id, handle, 0, om, esp32_bt_gattc_write_cb,
+                               (void *) resp_required);
+  }
+  if (ret != 0) {
+    LOG(LL_ERROR, ("ret = %d", ret));
+  }
+  return (ret == 0);
 }
 
 static int esp32_bt_gattc_add_disc_result_entry(

src/mgos_bt_js.c

@@ -103,8 +103,8 @@ bool mgos_bt_gattc_connect_js(const char *addr_s) {
 }
 
 bool mgos_bt_gattc_write_js(int conn_id, uint16_t handle,
-                            const struct mg_str *data) {
-  return mgos_bt_gattc_write(conn_id, handle, *data, true /* resp_required */);
+                            const struct mg_str *data, bool resp_required) {
+  return mgos_bt_gattc_write(conn_id, handle, *data, resp_required);
 }
 
 static const struct mjs_c_struct_member gattc_discovery_result_arg_def[] = {
@@ -155,6 +155,20 @@ const struct mjs_c_struct_member *mgos_bt_gattc_js_get_read_result_def(void) {
   return gattc_read_result_def;
 }
 
+static const struct mjs_c_struct_member gattc_write_result_def[] = {
+    {"conn", offsetof(struct mgos_bt_gattc_write_result_arg, conn),
+     MJS_STRUCT_FIELD_TYPE_STRUCT, gatt_conn_def},
+    {"handle", offsetof(struct mgos_bt_gattc_write_result_arg, handle),
+     MJS_STRUCT_FIELD_TYPE_UINT16, NULL},
+    {"ok", offsetof(struct mgos_bt_gattc_write_result_arg, ok),
+     MJS_STRUCT_FIELD_TYPE_BOOL, NULL},
+    {NULL},
+};
+
+const struct mjs_c_struct_member *mgos_bt_gattc_js_get_write_result_def(void) {
+  return gattc_write_result_def;
+}
+
 const struct mjs_c_struct_member *mgos_bt_gattc_js_get_notify_arg_def(void) {
   return gattc_read_result_def; /* Currently they are the same */
 }