// download_manager.cpp #include "download_manager.h" #include <curl/easy.h> #include <sys/stat.h>
(for building):
size_t DownloadManager::writeCallback(void* contents, size_t size, size_t nmemb, void* userp) size_t real_size = size * nmemb; auto* ctx = static_cast<DownloadContext*>(userp); if (ctx->file.is_open()) ctx->file.write(static_cast<char*>(contents), real_size); ctx->downloaded_bytes += real_size; // Trigger progress callback if (ctx->progress_cb && ctx->total_bytes > 0) float progress = (float)ctx->downloaded_bytes / ctx->total_bytes; ctx->progress_cb(progress, ctx->downloaded_bytes, ctx->total_bytes); return real_size; return 0; 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; // download_manager
class DownloadManager public: using ProgressCallback = std::function<void(float progress, size_t downloaded, size_t total)>; using CompleteCallback = std::function<void(bool success, const std::string& error)>; struct DownloadOptions std::string url; std::string output_path; int timeout_seconds = 30; int max_retries = 3; bool resume_on_failure = true; std::string username; // Optional for auth std::string password; // Optional for auth std::string user_agent = "C++DownloadManager/1.0"; ; DownloadManager(); ~DownloadManager(); // Start async download void downloadAsync(const DownloadOptions& options, ProgressCallback progress = nullptr, CompleteCallback complete = nullptr); // Sync download with progress bool downloadSync(const DownloadOptions& options, ProgressCallback progress = nullptr); // Cancel active download void cancel(); // Check if download is active bool isActive() const return m_active; // Get last error std::string getLastError() const return m_lastError; auto* ctx = static_cast<