loader: completely rewrite.

stratosphere/loader/source/ldr_ecs.cpp

@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) 2018-2019 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 <unordered_map>
+#include "ldr_ecs.hpp"
+
+namespace sts::ldr::ecs {
+
+    namespace {
+
+        /* Convenience definition. */
+        constexpr size_t DeviceNameSizeMax = 0x20;
+        constexpr size_t MaxExternalContentSourceCount = 0x10;
+
+        /* Types. */
+        class ExternalContentSource {
+            NON_COPYABLE(ExternalContentSource);
+            NON_MOVEABLE(ExternalContentSource);
+            private:
+                char device_name[DeviceNameSizeMax];
+            public:
+                ExternalContentSource(const char *dn){
+                    std::strncpy(this->device_name, dn, sizeof(this->device_name) - 1);
+                    this->device_name[sizeof(this->device_name) - 1] = '\0';
+                }
+
+                ~ExternalContentSource() {
+                    fsdevUnmountDevice(this->device_name);
+                }
+
+                const char *GetDeviceName() const {
+                    return this->device_name;
+                }
+        };
+
+        /* Global storage. */
+        std::unordered_map<u64, ExternalContentSource> g_map;
+    }
+
+    /* API. */
+    const char *Get(ncm::TitleId title_id) {
+        auto it = g_map.find(static_cast<u64>(title_id));
+        if (it == g_map.end()) {
+            return nullptr;
+        }
+        return it->second.GetDeviceName();
+    }
+
+    Result Set(Handle *out, ncm::TitleId title_id) {
+        if (g_map.size() >= MaxExternalContentSourceCount) {
+            /* TODO: Is this an appropriate error? */
+            return ResultLoaderTooManyArguments;
+        }
+
+        /* Clear any sources. */
+        R_ASSERT(Clear(title_id));
+
+        /* Generate mountpoint. */
+        char device_name[DeviceNameSizeMax];
+        std::snprintf(device_name, DeviceNameSizeMax, "ecs-%016lx", static_cast<u64>(title_id));
+
+        /* Create session. */
+        AutoHandle server, client;
+        {
+            Handle s_h, c_h;
+            R_TRY(svcCreateSession(&s_h, &c_h, 0, 0));
+            server.Reset(s_h);
+            client.Reset(c_h);
+        }
+
+        /* Create service. */
+        Service srv;
+        serviceCreate(&srv, client.Move());
+        FsFileSystem fs = { srv };
+
+        /* Try to mount. */
+        if (fsdevMountDevice(device_name, fs) == -1) {
+            serviceClose(&srv);
+            return ResultFsMountNameAlreadyExists;
+        }
+
+        /* Add to map. */
+        g_map.emplace(static_cast<u64>(title_id), device_name);
+        *out = server.Move();
+        return ResultSuccess;
+    }
+
+    Result Clear(ncm::TitleId title_id) {
+        /* Delete if present. */
+        auto it = g_map.find(static_cast<u64>(title_id));
+        if (it != g_map.end()) {
+            g_map.erase(it);
+        }
+        return ResultSuccess;
+    }
+
+}