From 5dc772e5072fd80ddf3757ff0fb1093e6ccd1af6 Mon Sep 17 00:00:00 2001
From: Jef Roosens <roosensjef@gmail.com>
Date: Thu, 25 May 2023 21:04:55 +0200
Subject: [PATCH] feat: added basic logging

---
 include/log.h               | 38 +++++++++++++++++++++++++++++++++++++
 src/event_loop/event_loop.c | 18 +++++++++++++-----
 src/log.c                   | 25 ++++++++++++++++++++++++
 3 files changed, 76 insertions(+), 5 deletions(-)
 create mode 100644 include/log.h
 create mode 100644 src/log.c

diff --git a/include/log.h b/include/log.h
new file mode 100644
index 0000000..2a33278
--- /dev/null
+++ b/include/log.h
@@ -0,0 +1,38 @@
+#ifndef LANDER_LOG
+#define LANDER_LOG
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+typedef enum log_level {
+  log_level_debug = 0,
+  log_level_info = 1,
+  log_level_warning = 2,
+  log_level_error = 3,
+  log_level_critical = 4,
+} log_level;
+
+extern const char *log_level_names[];
+
+void _lander_log(log_level level, FILE *f, const char *fmt, ...);
+
+#define flog(level, f, ...) _lander_log(level, f, __VA_ARGS__)
+#define log(level, ...) _lander_log(level, NULL, __VA_ARGS__)
+#define debug(...) _lander_log(log_level_debug, NULL, __VA_ARGS__)
+#define fdebug(f, ...) _lander_log(log_level_debug, f, __VA_ARGS__)
+#define info(...) _lander_log(log_level_info, NULL, __VA_ARGS__)
+#define finfo(f, ...) _lander_log(log_level_info, f, __VA_ARGS__)
+#define warning(...) _lander_log(log_level_warning, NULL, __VA_ARGS__)
+#define fwarning(f, ...) _lander_log(log_level_warning, f, __VA_ARGS__)
+#define error(...) _lander_log(log_level_error, NULL, __VA_ARGS__)
+#define ferror(f, ...) _lander_log(log_level_error, f, __VA_ARGS__)
+#define critical(status, ...)                                                  \
+  _lander_log(log_level_critical, NULL, __VA_ARGS__);                          \
+  exit(status)
+#define fcritical(status, f, ...)                                              \
+  _lander_log(log_level_critical, f, __VA_ARGS__);                             \
+  exit(status)
+
+#endif
diff --git a/src/event_loop/event_loop.c b/src/event_loop/event_loop.c
index 6dddf3c..3cf28ec 100644
--- a/src/event_loop/event_loop.c
+++ b/src/event_loop/event_loop.c
@@ -11,6 +11,7 @@
 #include <unistd.h>
 
 #include "event_loop_internal.h"
+#include "log.h"
 #include "picohttpparser.h"
 
 static int event_loop_fd_set_nb(int fd) {
@@ -97,7 +98,7 @@ void event_loop_run(event_loop *el, int port) {
   int fd = socket(AF_INET, SOCK_STREAM, 0);
 
   if (fd < 0) {
-    return;
+    critical(1, "Failed to open listening socket, errno: %i", errno);
   }
 
   int val = 1;
@@ -111,20 +112,24 @@ void event_loop_run(event_loop *el, int port) {
   int res = bind(fd, (const struct sockaddr *)&addr, sizeof(addr));
 
   if (res) {
-    return;
+    critical(1, "Failed to bind listening socket, errno: %i", errno);
   }
 
+  debug("Listening socket bound to fd %i", fd);
+
   res = listen(fd, SOMAXCONN);
 
   if (res) {
-    return;
+    critical(1, "Failed to start listening on listening socket, errno: %i",
+             errno);
   }
 
   // The listening socket is always poll'ed in non-blocking mode as well
   res = event_loop_fd_set_nb(fd);
 
   if (res != 0) {
-    return;
+    critical(1, "Failed to set listening socket to non-blocking, errno: %i",
+             errno);
   }
 
   // TODO don't hardcode the number 32
@@ -138,6 +143,8 @@ void event_loop_run(event_loop *el, int port) {
   event_loop_conn *conn;
   int events;
 
+  info("Starting event loop on port %i", port);
+
   while (1) {
     poll_args_count = 1;
 
@@ -165,8 +172,9 @@ void event_loop_run(event_loop *el, int port) {
     // poll for active fds
     // the timeout argument doesn't matter here
     int rv = poll(poll_args, (nfds_t)poll_args_count, 1000);
+
     if (rv < 0) {
-      return;
+      critical(1, "Poll failed, errno: %i", errno);
     }
 
     // process active connections
diff --git a/src/log.c b/src/log.c
new file mode 100644
index 0000000..b6b0ab6
--- /dev/null
+++ b/src/log.c
@@ -0,0 +1,25 @@
+#include <time.h>
+
+#include "log.h"
+
+const char *log_level_names[] = {"DEBUG", "INFO ", "WARN ", "ERROR",
+                                 "CRITICAL"};
+
+void _lander_log(log_level level, FILE *f, const char *fmt, ...) {
+  // Log to stdout by default
+  f = (f == NULL) ? stdout : f;
+
+  char date_str[32];
+
+  time_t now = time(NULL);
+  strftime(date_str, sizeof(date_str) - 1, "%Y-%m-%d %H:%M:%S",
+           localtime(&now));
+  fprintf(f, "[%s][%s] ", date_str, log_level_names[level]);
+
+  va_list ap;
+  va_start(ap, fmt);
+  vfprintf(f, fmt, ap);
+  va_end(ap);
+
+  fprintf(f, "\n");
+}