add file.create_memory_device, app.create_memory_device

src/engine/EnginePaths.cpp

@@ -2,6 +2,7 @@
 
 #include "debug/Logger.hpp"
 #include "io/devices/StdfsDevice.hpp"
+#include "io/devices/MemoryDevice.hpp"
 #include "io/devices/ZipFileDevice.hpp"
 #include "maths/util.hpp"
 #include "typedefs.hpp"
@@ -168,6 +169,18 @@ void EnginePaths::unmount(const std::string& name) {
     mounted.erase(found);
 }
 
+std::string EnginePaths::createMemoryDevice() {
+    auto device = std::make_unique<io::MemoryDevice>();
+        std::string name;
+    do {
+        name = std::string("M.") + generate_random_base64<6>();
+    } while (std::find(mounted.begin(), mounted.end(), name) != mounted.end());
+    
+    io::set_device(name, std::move(device));
+    mounted.push_back(name);
+    return name;
+}
+
 std::string EnginePaths::createWriteableDevice(const std::string& name) {
     const auto& found = writeables.find(name);
     if (found != writeables.end()) {

src/engine/EnginePaths.hpp

@@ -58,6 +58,7 @@ public:
     void unmount(const std::string& name);
 
     std::string createWriteableDevice(const std::string& name);
+    std::string createMemoryDevice();
 
     void setEntryPoints(std::vector<PathsRoot> entryPoints);
 

src/logic/scripting/lua/libs/libapp.cpp

@@ -1,6 +1,21 @@
 #include "api_lua.hpp"
 
+#include "io/io.hpp"
+#include "io/devices/MemoryDevice.hpp"
+
+static int l_create_memory_device(lua::State* L) {
+    auto name = lua::require_string(L, 1);
+    if (io::get_device(name)) {
+        throw std::runtime_error(
+            "entry-point '" + std::string(name) + "' is already used"
+        );
+    }
+    io::set_device(name, std::make_unique<io::MemoryDevice>());
+    return 0;
+}
+
 const luaL_Reg applib[] = {
+    {"create_memory_device", lua::wrap<l_create_memory_device>},
     // see libcore.cpp an stdlib.lua
     {nullptr, nullptr}
 };

src/logic/scripting/lua/libs/libfile.cpp

@@ -221,6 +221,16 @@ static int l_unmount(lua::State* L) {
     return 0;
 }
 
+static int l_create_memory_device(lua::State* L) {
+    if (lua::isstring(L, 1)) {
+        throw std::runtime_error(
+            "name must not be specified, use app.create_memory_device instead"
+        );
+    }
+    auto& paths = engine->getPaths();
+    return lua::pushstring(L, paths.createMemoryDevice());
+}
+
 static int l_create_zip(lua::State* L) {
     io::path folder = lua::require_string(L, 1);
     io::path outFile = lua::require_string(L, 2);
@@ -336,7 +346,6 @@ static int l_write_descriptor(lua::State* L) {
     if (!stream->good()) {
         throw std::runtime_error("failed to write to stream");
     }
-
     return 0;
 }
 
@@ -352,7 +361,6 @@ static int l_flush_descriptor(lua::State* L) {
     }
 
     scripting::descriptors_manager::flush(descriptor);
-
     return 0;
 }
 
@@ -364,13 +372,11 @@ static int l_close_descriptor(lua::State* L) {
     }
 
     scripting::descriptors_manager::close(descriptor);
-
     return 0;
 }
 
 static int l_close_all_descriptors(lua::State* L) {
     scripting::descriptors_manager::close_all_descriptors();
-
     return 0;
 }
 
@@ -396,6 +402,7 @@ const luaL_Reg filelib[] = {
     {"is_writeable", lua::wrap<l_is_writeable>},
     {"mount", lua::wrap<l_mount>},
     {"unmount", lua::wrap<l_unmount>},
+    {"create_memory_device", lua::wrap<l_create_memory_device>},
     {"create_zip", lua::wrap<l_create_zip>},
     {"__open_descriptor", lua::wrap<l_open_descriptor>},
     {"__has_descriptor", lua::wrap<l_has_descriptor>},