| // Copyright 2020 Google LLC |
| // |
| // Licensed 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 |
| // |
| // https://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 "callbacks.h" // NOLINT(build/include) |
| |
| #include <iostream> |
| |
| size_t g_iterations = 0; |
| size_t constexpr kMaxIterations = 1'000'000; |
| static char g_buffer[1024]; |
| static uv_buf_t g_iov; |
| |
| // Stop the handle if the methods was called kMaxIterations times |
| void IdleCallback(uv_idle_t* handle) { |
| ++g_iterations; |
| if (g_iterations > kMaxIterations) { |
| std::cout << "IdleCallback was called " << kMaxIterations << " times" |
| << std::endl; |
| uv_idle_stop(handle); |
| } |
| } |
| |
| // Called after some chars have been written |
| // As soon as writing of these bytes is completed, read more |
| void OnWrite(uv_fs_t* req) { |
| if (req->result < 0) { |
| std::cerr << "Write error: " << uv_strerror(static_cast<int>(req->result)) |
| << std::endl; |
| return; |
| } |
| // Start reading more after writing these bytes |
| uv_fs_read(uv_default_loop(), &read_req, open_req.result, &g_iov, 1, -1, |
| OnRead); |
| } |
| |
| // Called after some chars have been read |
| // As soon as reading of these bytes is completed, write them |
| void OnRead(uv_fs_t* req) { |
| if (req->result < 0) { |
| std::cerr << "Read error: " << uv_strerror(req->result) << std::endl; |
| return; |
| } |
| if (req->result == 0) { |
| // No more bytes left, close the loop |
| uv_fs_t close_req; |
| uv_fs_close(uv_default_loop(), &close_req, open_req.result, NULL); |
| } else if (req->result > 0) { |
| // Start writing after reading some bytes |
| g_iov.len = req->result; |
| uv_fs_write(uv_default_loop(), &write_req, 1, &g_iov, 1, -1, OnWrite); |
| } |
| } |
| |
| // Called after the file has been opened |
| // As soon as opening is completed, read the file |
| void OnOpen(uv_fs_t* req) { |
| if (req != &open_req) { |
| std::cerr << "Open error: req != &open_req" << std::endl; |
| return; |
| } |
| if (req->result < 0) { |
| std::cerr << "Open error: " << uv_strerror(static_cast<int>(req->result)) |
| << std::endl; |
| return; |
| } |
| // Initialize uv_buf_t g_buffer |
| g_iov = uv_buf_init(g_buffer, sizeof(g_buffer)); |
| // Start reading after opening |
| uv_fs_read(uv_default_loop(), &read_req, req->result, &g_iov, 1, -1, OnRead); |
| } |
| |
| // Get the integer pointed by handle->data and increment it by one |
| // Then close the handle |
| void TimerCallback(uv_timer_t* handle) { |
| int* data = static_cast<int*>( |
| uv_handle_get_data(reinterpret_cast<uv_handle_t*>(handle))); |
| ++(*data); |
| uv_close(reinterpret_cast<uv_handle_t*>(handle), nullptr); |
| } |