1 files changed, 72 insertions, 0 deletions
diff --git a/include/mercury/kernel/application.hpp b/include/mercury/kernel/application.hpp
new file mode 100644
index 0000000..bc4a763
--- /dev/null
+++ b/include/mercury/kernel/application.hpp
@@ -0,0 +1,72 @@
+#ifndef MERCURY_KERNEL_APPLICATION_HPP
+#define MERCURY_KERNEL_APPLICATION_HPP
+
+#include <mercury/kernel/vfile.hpp>
+#include <cstdint>
+
+namespace mercury::kernel::application {
+
+  enum class app_state {
+    running,
+    paused,
+    zombie
+  };
+
+  struct app_instance {
+
+    app_state state;
+
+    uint64_t *p4;
+    uint64_t *p3;
+    uint64_t *p2;
+
+    bool *p2es_to_free_on_exit;
+
+    uint64_t p4_paddr;
+
+    //set to 0 if none
+    uint64_t framebuffer_vaddr;
+
+    //only valid if state is zombie
+    int exit_code;
+
+    //only valid if state is paused
+    struct {
+      uint64_t rip;
+      uint64_t rsp;
+      //TODO: etc.
+    } saved_regs;
+
+    app_instance();
+    ~app_instance();
+
+    //2MiB page. vaddr and paddr must be aligned, and vaddr in valid range.
+    void map_page(uint64_t vaddr, uint64_t paddr,
+      bool write, bool execute, bool free_pram_on_exit);
+
+    //2MiB pages. returns start of first page.
+    uint64_t get_free_vaddr_pages(uint64_t count);
+
+    void create_stack();
+
+    void set_instruction_pointer(uint64_t vaddr);
+
+    //2MiB pages; only lower half.
+    uint64_t count_mapped_vram_pages();
+
+  };
+
+  extern app_instance *running_app;
+
+  enum class create_app_result {
+    success,
+    device_error,
+    app_corrupt,
+    fs_corrupt
+  };
+
+  create_app_result create_app(const vfile::vfile &file, app_instance *&out);
+
+}
+
+#endif