backend: begin work on epoll

backend/Makefile

@@ -37,7 +37,10 @@ build_dir = build
 obj_dir = $(build_dir)/obj
 
 sources = \
-	src/main.cpp
+	src/main.cpp \
+	src/tcp.cpp \
+	src/http.cpp
+
 
 target=$(build_dir)/backend
 

backend/src/tcp.cpp

@@ -10,6 +10,7 @@
 #include <string.h>
 #include <string>
 #include <string_view>
+#include <sys/epoll.h>
 #include <sys/socket.h>
 #include <unistd.h>
 
@@ -61,14 +62,20 @@ auto TcpListener::bind(const std::string& host, uint16_t port)
         return std::unexpected(errno_shim("could not listen"));
     }
 
-    return TcpListener(socket_fd, address);
+    auto epoll_fd = ::epoll_create(0);
+
+    auto events_accepted = epoll_event { .events = EPOLLIN, .data = { } };
+    if (::epoll_ctl(epoll_fd, EPOLL_CTL_ADD, socket_fd, &events_accepted) < 0) {
+        return std::unexpected(errno_shim("could not connect to epoll"));
+    }
+
+    return TcpListener(socket_fd, epoll_fd, address);
 }
 
 auto TcpListener::accept() -> Result<TcpConnection>
 {
     socklen_t size = sizeof(address);
-
-    int socket = ::accept(this->fd, (struct sockaddr*)&address, &size);
+    int socket = ::accept(this->listener_fd, (struct sockaddr*)&address, &size);
     if (socket < 0) {
         return std::unexpected(errno_shim("could not accept"));
     }

backend/src/tcp.hpp

@@ -4,6 +4,7 @@
 #include <expected>
 #include <netinet/in.h>
 #include <string>
+#include <vector>
 
 namespace mst {
 template <typename T> using Result = std::expected<T, std::string>;
@@ -29,10 +30,13 @@ public:
     auto accept() -> Result<TcpConnection>;
 
 private:
-    TcpListener(int fd, sockaddr_in address)
-        : fd(fd)
+    TcpListener(int listener_fd, int epoll_fd, sockaddr_in address)
+        : listener_fd(listener_fd)
+        , epoll_fd(epoll_fd)
         , address(address) { };
-    int fd;
+    int listener_fd;
+    int epoll_fd;
     sockaddr_in address;
+    std::vector<int> epoll_fds;
 };
 }