Runtime C++ ((top)) Download -
DownloadManager::~DownloadManager() cancel(); if (m_downloadThread.joinable()) m_downloadThread.join(); if (m_curl) curl_easy_cleanup(m_curl); curl_global_cleanup();
# Install libcurl (Ubuntu/Debian) sudo apt-get install libcurl4-openssl-dev mkdir build && cd build cmake .. && make Run ./downloader
int DownloadManager::progressCallback(void* userp, curl_off_t dltotal, curl_off_t dlnow, curl_off_t ultotal, curl_off_t ulnow) auto* ctx = static_cast<DownloadContext*>(userp); if (dltotal > 0) ctx->total_bytes = dltotal; if (ctx->progress_cb) float progress = (float)dlnow / dltotal; ctx->progress_cb(progress, dlnow, dltotal); return 0; // Return non-zero to cancel runtime c++ download
int main() DownloadManager dm; DownloadManager::DownloadOptions options; options.url = "https://example.com/file.zip"; options.output_path = "downloaded_file.zip"; options.max_retries = 2; options.resume_on_failure = true; std::cout << "Starting download..." << std::endl; auto start_time = std::chrono::steady_clock::now(); // Async download with callbacks dm.downloadAsync(options, // Progress callback [](float progress, size_t downloaded, size_t total) std::cout << "\rProgress: " << (progress * 100) << "% (" << downloaded << "/" << total << " bytes)" << std::flush; , // Complete callback [&start_time](bool success, const std::string& error) auto end_time = std::chrono::steady_clock::now(); auto duration = std::chrono::duration_cast<std::chrono::seconds>(end_time - start_time); if (success) std::cout << "\nDownload completed in " << duration.count() << " seconds!" << std::endl; else std::cout << "\nDownload failed: " << error << std::endl; ); // Wait for completion while (dm.isActive()) std::this_thread::sleep_for(std::chrono::milliseconds(100)); return 0;
find_package(CURL REQUIRED)
private: static size_t writeCallback(void* contents, size_t size, size_t nmemb, void* userp); static int progressCallback(void* userp, curl_off_t dltotal, curl_off_t dlnow, curl_off_t ultotal, curl_off_t ulnow); struct DownloadContext std::ofstream file; size_t downloaded_bytes = 0; size_t total_bytes = 0; ProgressCallback progress_cb; std::string output_path; bool resume_mode = false; ; std::unique_ptr<DownloadContext> m_context; std::thread m_downloadThread; std::atomic<bool> m_activefalse; std::atomic<bool> m_cancelfalse; std::string m_lastError; CURL* m_curl; ;
void DownloadManager::cancel() m_cancel = true; if (m_downloadThread.joinable()) m_downloadThread.join(); if (m_downloadThread.joinable()) m_downloadThread.join()
target_link_libraries(downloader $CURL_LIBRARIES) target_include_directories(downloader PRIVATE $CURL_INCLUDE_DIRS)