Initial commit

- basic main.c implementation
- event_loop implementation

main.c

@@ -0,0 +1,99 @@
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdint.h>
+
+#include <errno.h>
+#include <signal.h>
+#include <sys/epoll.h>
+#include <sys/signalfd.h>
+
+#include "event_loop.h"
+
+/*
+ * Data
+ */
+static bool _to_work = true;
+static int _sig_fd = -1;
+
+/*
+ * Private API
+ */
+// Initialize signals.
+// Returns:
+//  - true on success
+// Remarks:
+//  - loop_init() must be called before this one
+static bool signals_init() {
+    sigset_t mask;
+    sigemptyset(&mask);
+    sigaddset(&mask, SIGTERM);
+    sigaddset(&mask, SIGINT);
+    sigaddset(&mask, SIGQUIT);
+    if (sigprocmask(SIG_BLOCK, &mask, NULL) == -1) {
+        printf("[!] sigprocmask failed: %d\n", errno);
+        return false;
+    }
+    _sig_fd = signalfd(
+        -1,
+        &mask,
+        SFD_NONBLOCK
+    );
+    if (_sig_fd == -1) {
+        printf("[!] signalfd failed: %d\n", errno);
+        return false;
+    }
+    struct epoll_event ev;
+    ev.data.fd = _sig_fd;
+    ev.events = EPOLLIN;
+    bool loop_res = loop_ctl(
+        EPOLL_CTL_ADD,
+        _sig_fd,
+        &ev
+    );
+    if (!loop_res) {
+        close(_sig_fd);
+        printf("[!] loop_ctl failed\n");
+        return false;
+    }
+    return true;
+}
+
+static void signals_deinit() {
+    close(_sig_fd);
+}
+
+/*
+ * Callbacks and main
+ */
+// This callback is called by loop_wait when event happens.
+static void on_fd_event(int fd, uint32_t events) {
+    // Termination
+    if (fd == _sig_fd) {
+        _to_work = false;
+    }
+    else {
+        printf("[!] Event has happened on an unknown file descriptor\n");
+    }
+}
+
+int main(int argc, char **argv) {
+    if (!loop_init(on_fd_event)) {
+        return 1;
+    }
+    if (!signals_init()) {
+        loop_deinit();
+        return 1;
+    }
+
+    while (_to_work) {
+        if (!loop_wait()) {
+            printf("[!] loop_wait returns false, stopping...\n");
+            break;
+        }
+        printf("--- loop ---\n");
+    }
+    
+    signals_deinit();
+    loop_deinit();
+    return 0;
+}