unpack PSP pkg files to CSO

pkg2zip_out.h

@@ -5,6 +5,12 @@
 void out_begin(const char* name, int zipped);
 void out_end(void);
 void out_add_folder(const char* path);
-void out_begin_file(const char* name, int compress);
+uint64_t out_begin_file(const char* name, int compress);
 void out_end_file(void);
 void out_write(const void* buffer, uint32_t size);
+
+// hacky solution to be able to write cso header after the data is written
+void out_write_at(uint64_t offset, const void* buffer, uint32_t size);
+void out_set_offset(uint64_t offset);
+uint32_t out_zip_get_crc32(void);
+void out_zip_set_crc32(uint32_t crc);