Function AP_Logger_Write

libraries/AP_Scripting/lua_bindings.cpp:260–561

#if HAL_LOGGING_ENABLED
int AP_Logger_Write(lua_State *L) {
    AP_Logger * AP_logger = AP_Logger::get_singleton();
    if (AP_logger == nullptr) {
        return luaL_argerror(L, 1, "logger not supported on this firmware");
    }

    // Allow : and . access
    const int arg_offset = (luaL_testudata(L, 1, "logger") != NULL) ? 1 : 0;

    // check we have at least 4 arguments passed in
    const int args = lua_gettop(L) - arg_offset;
    if (args < 4) {
        return luaL_argerror(L, args, "too few arguments");
    }

    const char * name = luaL_checkstring(L, 1 + arg_offset);
    const char * labels = luaL_checkstring(L, 2 + arg_offset);
    const char * fmt = luaL_checkstring(L, 3 + arg_offset);

    // cheack the name, labels and format are not too long
    if (strlen(name) >= LS_NAME_SIZE) {
        return luaL_error(L, "Name must be 4 or less chars long");
    }
    uint8_t length = strlen(labels);
    if (length >= (LS_LABELS_SIZE - 7)) { // need 7 chars to add 'TimeUS,'
        return luaL_error(L, "labels must be less than 58 chars long");
    }
    // Count the number of commas
    uint8_t commas = 1;
    for (uint8_t i=0; i<length; i++) {
        if (labels[i] == ',') {
            commas++;
        }
    }

    length = strlen(fmt);
    if (length >= (LS_FORMAT_SIZE - 1)) { // need 1 char to add timestamp
        return luaL_error(L, "format must be less than 15 chars long");
    }

    // check the number of arguments matches the number of values in the label
    if (length != commas) {
        return luaL_argerror(L, args, "label does not match format");
    }

    bool have_units = false;
    if (args - 5 == length) {
        // check if there are enough arguments for units and multiplyers
        have_units = true;
    } else if (args - 3 != length) {
        // check the number of arguments matches the length of the foramt string
        return luaL_argerror(L, args, "format does not match No. of arguments");
    }

    // prepend timestamp to format and labels
    char label_cat[LS_LABELS_SIZE];
    strcpy(label_cat,"TimeUS,");
    strcat(label_cat,labels);