first commit: echo server

2026-09-07 00:45:35 +02:00
commit b15ce130f9
47 changed files with 2614 additions and 0 deletions
@@ -0,0 +1,96 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   FileDescriptor.cpp                                 :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: acossari <acossari@student.codam.nl>       +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2026/08/24 16:23:52 by acossari          #+#    #+#             */
+/*   Updated: 2026/08/28 16:13:23 by acossari         ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+#include "net/FileDescriptor.hpp"
+
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <cerrno>
+#include <cstring>
+#include <format>
+#include <utility>
+
+namespace webserv {
+
+// "Sink parameter": consumes the local parameter by moving its value into msg_
+// lvalue -> copy into message -> move into msg_ (1 copy, worst case scenario)
+// rvalue -> move into message -> move into msg_ (0 copies)
+FileDescriptor::Error::Error(std::string message) : msg_(std::move(message)) {}
+
+const char* FileDescriptor::Error::what() const noexcept {
+  return msg_.c_str();
+}
+
+// A valid fd is either made close-on-exec or closed before construction fails.
+FileDescriptor::FileDescriptor(int fd) : fd_(fd) {
+  if (fd_ < 0) {
+    return;
+  }
+
+  // fork() inherits this fd, but a successful execve() closes it before the
+  // new program starts, preventing CGI processes from retaining server fds.
+  if (::fcntl(fd_, F_SETFD, FD_CLOEXEC) == -1) {
+    // The subject forbids errno only after read/recv/write/send.
+    // Save it before close(), which may overwrite the original fcntl error.
+    const int errnoCode = errno;
+    ::close(fd_);
+    fd_ = -1;
+    throw Error(std::format("fcntl(F_SETFD, FD_CLOEXEC) on fd {}: {}", fd,
+                            std::strerror(errnoCode)));
+  }
+}
+
+FileDescriptor::~FileDescriptor() {
+  reset();
+}
+
+// The FileDescriptor&& parameter is an rvalue reference and a sink. It accepts
+// only a temporary or an object passed with std::move(). The constructor takes
+// ownership of that object's fd, so only the new FileDescriptor will close it.
+FileDescriptor::FileDescriptor(FileDescriptor&& other) noexcept
+    : fd_(std::exchange(other.fd_, -1)) {}
+
+FileDescriptor& FileDescriptor::operator=(FileDescriptor&& other) noexcept {
+  if (this != &other) {
+    reset();
+    fd_ = std::exchange(other.fd_, -1);
+  }
+  return *this;
+}
+
+void FileDescriptor::setNonBlocking() {
+  if (!valid()) {
+    throw Error("setNonBlocking() on an invalid file descriptor");
+  }
+
+  // Read, modify, write pattern: F_SETFL replaces the whole status flags word,
+  // so passing O_NONBLOCK alone would clear whatever else is set.
+  const int flags = ::fcntl(fd_, F_GETFL);
+  if (flags == -1) {
+    throw Error(
+        std::format("fcntl(F_GETFL) on fd {}: {}", fd_, std::strerror(errno)));
+  }
+  if (::fcntl(fd_, F_SETFL, flags | O_NONBLOCK) == -1) {
+    throw Error(std::format("fcntl(F_SETFL, O_NONBLOCK) on fd {}: {}", fd_,
+                            std::strerror(errno)));
+  }
+}
+
+void FileDescriptor::reset() noexcept {
+  if (fd_ >= 0) {
+    ::close(fd_);
+    fd_ = -1;
+  }
+}
+
+}  // namespace webserv