szaszm commented on a change in pull request #674: Minificpp 1007 - ECU C2 integration. URL: https://github.com/apache/nifi-minifi-cpp/pull/674#discussion_r371958040
########## File path: nanofi/src/core/ring_buffer.c ########## @@ -0,0 +1,99 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. +*/ + +#include <core/ring_buffer.h> + +size_t min(size_t x, size_t y) { + if (x <= y) { + return x; + } + return y; +} + +size_t write_ring_buffer(ring_buffer_t * rb, const char * payload, size_t length) { + if (!rb || !rb->data || !payload || !length) { + return 0; + } + + if (rb->capacity - rb->size == 0) { + //buffer is full + return 0; + } + + size_t capacity = rb->capacity; + size_t available = capacity - rb->size; + size_t bytes_to_write = min(available, length); + + if (bytes_to_write <= (capacity - rb->write_index)) { + memcpy(rb->data + rb->write_index, payload, bytes_to_write); + rb->write_index += bytes_to_write; + if (rb->write_index == rb->capacity) { + rb->write_index = 0; + } + } else { + //rotate and write + size_t size1 = capacity - rb->write_index; + memcpy(rb->data + rb->write_index, payload, size1); + size_t size2 = bytes_to_write - size1; + memcpy(rb->data, payload + size1, size2); + rb->write_index = size2; + } + rb->size += bytes_to_write; + return bytes_to_write; +} + +size_t read_ring_buffer(ring_buffer_t * rb, char * payload, size_t length) { + if (!rb || !rb->data || !payload || !length) { + return 0; + } + + if (rb->size == 0) { + //buffer is empty + return 0; + } + + size_t capacity = rb->capacity; + size_t bytes_to_read = min(rb->size, length); + + if (bytes_to_read <= (capacity - rb->read_index)) { + memcpy(payload, rb->data + rb->read_index, bytes_to_read); + rb->read_index += bytes_to_read; + if (rb->read_index == rb->capacity) { + rb->read_index = 0; + } + } else { + size_t size1 = capacity - rb->read_index; + memcpy(payload, rb->data + rb->read_index, size1); + size_t size2 = bytes_to_read - size1; + memcpy(payload + size1, rb->data, size2); + rb->read_index = size2; + } + rb->size -= bytes_to_read; + return bytes_to_read; +} + +size_t check_available_space(ring_buffer_t * rb) { + //this is a hypothetical situation. no harm in safety check + if (rb->capacity < rb->size) + return 0; + return rb->capacity - rb->size; +} + +void free_ring_buffer(ring_buffer_t * rb) { + free(rb->data); Review comment: Missing `#include <stdlib.h>` ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
