feat|perf: generic&efficient desktop&config parser

include/desktop.h

@@ -0,0 +1,17 @@
+#ifndef DESKTOPH_
+#define DESKTOPH_
+
+#include <stdbool.h>
+#include <stdio.h>
+
+#include "macros.h"
+
+struct status {
+  bool finish;
+  int ret;
+};
+
+int read_desktop(FILE* fd, void* ctx, struct status (*cb)(void* ctx, char* NULLABLE table,
+                                               char* key, char* value));
+
+#endif

include/macros.h

@@ -0,0 +1,12 @@
+// Do we just replace the compiler with clang??
+#if defined(__clang__)
+  #define NULLABLE _Nullable
+#else
+  #define NULLABLE
+#endif
+
+#if defined(__clang__)
+  #define NNULLABLE _Nonnull
+#else
+  #define NNULLABLE
+#endif

include/sessions.h

@@ -3,6 +3,7 @@
 
 #include <sys/types.h>
 
+#include "macros.h"
 #include "util.h"
 
 enum session_type {
@@ -12,9 +13,9 @@ enum session_type {
 };
 
 struct session {
-  char* name;
-  char* exec;
-  char* tryexec;
+  char* NNULLABLE name;
+  char* NNULLABLE exec;
+  char* NULLABLE tryexec;
   enum session_type type;
 };