AP_Scripting: added readstring for uarts

this is much more efficient than reading a byte at a time
ArduPilot · Dec 10, 2023 · d1893f0 · d1893f0
1 parent 83559c4
commit d1893f0
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Showing 4 changed files with 34 additions and 0 deletions.
diff --git a/libraries/AP_Scripting/docs/docs.lua b/libraries/AP_Scripting/docs/docs.lua
@@ -1064,6 +1064,14 @@ function AP_HAL__UARTDriver_ud:read() end
 ---@param baud_rate uint32_t_ud
 function AP_HAL__UARTDriver_ud:begin(baud_rate) end
 
+--[[
+  read count bytes from a uart and return as a lua string. Note
+  that the returned string can be shorter than the requested length
+--]]
+---@param count integer
+---@return string|nil
+function AP_HAL__UARTDriver_ud:readstring(count) end
+
 
 -- desc
 ---@class RC_Channel_ud

diff --git a/libraries/AP_Scripting/generator/description/bindings.desc b/libraries/AP_Scripting/generator/description/bindings.desc
@@ -357,6 +357,7 @@ include AP_SerialManager/AP_SerialManager.h
 ap_object AP_HAL::UARTDriver depends HAL_GCS_ENABLED
 ap_object AP_HAL::UARTDriver method begin void uint32_t 1U UINT32_MAX
 ap_object AP_HAL::UARTDriver method read int16_t
+ap_object AP_HAL::UARTDriver manual readstring AP_HAL__UARTDriver_readstring 1
 ap_object AP_HAL::UARTDriver method write uint32_t uint8_t'skip_check
 ap_object AP_HAL::UARTDriver method available uint32_t
 ap_object AP_HAL::UARTDriver method set_flow_control void AP_HAL::UARTDriver::flow_control'enum AP_HAL::UARTDriver::FLOW_CONTROL_DISABLE AP_HAL::UARTDriver::FLOW_CONTROL_AUTO

diff --git a/libraries/AP_Scripting/lua_bindings.cpp b/libraries/AP_Scripting/lua_bindings.cpp
@@ -632,6 +632,30 @@ int AP_HAL__I2CDevice_read_registers(lua_State *L) {
     return success;
 }
 
+int AP_HAL__UARTDriver_readstring(lua_State *L) {
+    binding_argcheck(L, 2);
+
+    AP_HAL::UARTDriver * ud = *check_AP_HAL__UARTDriver(L, 1);
+
+    const uint16_t count = get_uint16_t(L, 2);
+    uint8_t *data = (uint8_t*)malloc(count);
+    if (data == nullptr) {
+        return 0;
+    }
+
+    const auto ret = ud->read(data, count);
+    if (ret < 0) {
+        free(data);
+        return 0;
+    }
+
+    // push to lua string
+    lua_pushlstring(L, (const char *)data, ret);
+    free(data);
+
+    return 1;
+}
+
 #if AP_SCRIPTING_CAN_SENSOR_ENABLED
 int lua_get_CAN_device(lua_State *L) {
 

diff --git a/libraries/AP_Scripting/lua_bindings.h b/libraries/AP_Scripting/lua_bindings.h
@@ -8,6 +8,7 @@ int lua_mission_receive(lua_State *L);
 int AP_Logger_Write(lua_State *L);
 int lua_get_i2c_device(lua_State *L);
 int AP_HAL__I2CDevice_read_registers(lua_State *L);
+int AP_HAL__UARTDriver_readstring(lua_State *L);
 int lua_get_CAN_device(lua_State *L);
 int lua_get_CAN_device2(lua_State *L);
 int lua_dirlist(lua_State *L);