fix: neccessary code changes for nix

Makefile

@@ -10,7 +10,9 @@ PREFIX=/usr
 
 CC?=gcc
 CFLAGS?=-O3 -Wall
-ALLFLAGS=$(CFLAGS) -I$(IDIR)
+# C PreProcessor flags, not C Plus Plus
+CPPFLAGS?=
+ALLFLAGS=$(CFLAGS) $(CPPFLAGS) -I$(IDIR)
 
 LIBS=-lpam
 

src/config.c

@@ -240,12 +240,11 @@ struct status config_line_handler(void* _config, char* table, char* k,
 int parse_config(struct config* NNULLABLE config, char* NNULLABLE path) {
   FILE* fd = fopen(path, "r");
   if (fd == NULL) {
-    perror("fopen");
-    (void)fputs(
-        "Please place a config file at /etc/lidm.ini or set the LIDM_CONF "
-        "env variable",
-        stderr);
-    return -1;
+    log_perror("fopen");
+    log_printf(
+        " [I] No config, place one at /etc/lidm.ini or set the LIDM_CONF "
+        "env variable");
+    return 0; // Its fine now anyways
   }
 
   bool ret = read_desktop(fd, config, config_line_handler);

src/main.c

@@ -72,6 +72,7 @@ int main(int argc, char* argv[]) {
     chvt_str(argv[1]);
   }
 
+  // Copy
   struct config config = DEFAULT_CONFIG;
   char* conf_override = getenv("LIDM_CONF");
   char* conf_path = conf_override ? conf_override : "/etc/lidm.ini";

src/sessions.c

@@ -16,9 +16,16 @@ struct source_dir {
   enum session_type type;
   char* dir;
 };
+
+#ifndef SESSIONS_XSESSIONS
+  #define SESSIONS_XSESSIONS "/usr/share/xsessions"
+#endif
+#ifndef SESSIONS_WAYLAND
+  #define SESSIONS_WAYLAND "/usr/share/wayland-sessions"
+#endif
 static const struct source_dir SOURCES[] = {
-    {XORG, "/usr/share/xsessions"},
-    {WAYLAND, "/usr/share/wayland-sessions"},
+    {XORG, SESSIONS_XSESSIONS},
+    {WAYLAND, SESSIONS_WAYLAND},
 };
 
 static struct Vector* cb_sessions = NULL;