loader: refactor to use fs bindings

libraries/libstratosphere/source/fssystem/fssystem_external_code.cpp

@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <stratosphere.hpp>
+
+namespace ams::fssystem {
+
+    namespace {
+
+        constexpr inline size_t MaxExternalCodeFileSystem = 0x10;
+
+        util::BoundedMap<ncm::ProgramId, fs::RemoteFileSystem, MaxExternalCodeFileSystem> g_ecs_map;
+        util::BoundedMap<ncm::ProgramId, os::ManagedHandle,    MaxExternalCodeFileSystem> g_hnd_map;
+
+    }
+
+
+    fs::fsa::IFileSystem *GetExternalCodeFileSystem(ncm::ProgramId program_id) {
+        /* Return a fs from the map if one exists. */
+        if (auto *fs = g_ecs_map.Find(program_id); fs != nullptr) {
+            return fs;
+        }
+
+        /* Otherwise, we may have a handle. */
+        if (auto *hnd = g_hnd_map.Find(program_id); hnd != nullptr) {
+            /* Create a service using libnx bindings. */
+            Service srv;
+            serviceCreate(std::addressof(srv), hnd->Move());
+            g_hnd_map.Remove(program_id);
+
+            /* Create a remote filesystem. */
+            const FsFileSystem fs = { srv };
+            g_ecs_map.Emplace(program_id, fs);
+
+            /* Return the created filesystem. */
+            return g_ecs_map.Find(program_id);
+        }
+
+        /* Otherwise, we have no filesystem. */
+        return nullptr;
+    }
+
+    Result CreateExternalCode(Handle *out, ncm::ProgramId program_id) {
+        /* Create a handle pair. */
+        Handle server, client;
+        R_TRY(svcCreateSession(std::addressof(server), std::addressof(client), false, 0));
+
+        /* Insert the handle into the map. */
+        g_hnd_map.Emplace(program_id, client);
+
+        *out = server;
+        return ResultSuccess();
+    }
+
+    void DestroyExternalCode(ncm::ProgramId program_id) {
+        g_ecs_map.Remove(program_id);
+        g_hnd_map.Remove(program_id);
+    }
+
+}

libraries/libstratosphere/source/fssystem/fssystem_utility.cpp

@@ -51,6 +51,22 @@ namespace ams::fssystem {
             return ResultSuccess();
         }
 
+        Result HasEntry(bool *out, fs::fsa::IFileSystem *fsa, const char *path, fs::DirectoryEntryType type) {
+            /* Set out to false initially. */
+            *out = false;
+
+            /* Try to get the entry type. */
+            fs::DirectoryEntryType entry_type;
+            R_TRY_CATCH(fsa->GetEntryType(std::addressof(entry_type), path)) {
+                /* If the path doesn't exist, nothing has gone wrong. */
+                R_CONVERT(fs::ResultPathNotFound, ResultSuccess());
+            } R_END_TRY_CATCH;
+
+            /* We succeeded. */
+            *out = entry_type == type;
+            return ResultSuccess();
+        }
+
     }
 
     Result CopyFile(fs::fsa::IFileSystem *dst_fs, fs::fsa::IFileSystem *src_fs, const char *dst_parent_path, const char *src_path, const fs::DirectoryEntry *entry, void *work_buf, size_t work_buf_size) {
@@ -117,6 +133,14 @@ namespace ams::fssystem {
         );
     }
 
+    Result HasFile(bool *out, fs::fsa::IFileSystem *fs, const char *path) {
+        return HasEntry(out, fs, path, fs::DirectoryEntryType_File);
+    }
+
+    Result HasDirectory(bool *out, fs::fsa::IFileSystem *fs, const char *path) {
+        return HasEntry(out, fs, path, fs::DirectoryEntryType_Directory);
+    }
+
     Result EnsureDirectoryRecursively(fs::fsa::IFileSystem *fs, const char *path) {
         return EnsureDirectoryRecursivelyImpl(fs, path, true);
     }