Implement NCM

stratosphere/ncm/source/impl/ncm_placeholder_accessor.cpp

@@ -0,0 +1,233 @@
+/*
+ * Copyright (c) 2019 Adubbz
+ *
+ * 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 "ncm_placeholder_accessor.hpp"
+#include "../ncm_fs.hpp"
+#include "../ncm_utils.hpp"
+#include "../ncm_make_path.hpp"
+#include "../ncm_path_utils.hpp"
+
+namespace sts::ncm::impl {
+
+    unsigned int PlaceHolderAccessor::GetDirectoryDepth() {
+        if (this->make_placeholder_path_func == static_cast<MakePlaceHolderPathFunc>(path::MakePlaceHolderPathFlat)) {
+            return 1;
+        } else if (this->make_placeholder_path_func == static_cast<MakePlaceHolderPathFunc>(path::MakePlaceHolderPathHashByteLayered)) {
+            return 2;
+        }
+
+        std::abort();
+    }
+
+    void PlaceHolderAccessor::GetPlaceHolderPathUncached(char* placeholder_path_out, PlaceHolderId placeholder_id) {
+        std::scoped_lock<HosMutex> lock(this->cache_mutex);
+
+        if (placeholder_id != InvalidUuid) {
+            CacheEntry* found_cache = NULL;
+            
+            for (size_t i = 0; i < PlaceHolderAccessor::MaxCaches; i++) {
+                CacheEntry* cache = &this->caches[i];
+
+                if (placeholder_id == cache->id) {
+                    found_cache = cache;
+                    break;
+                }
+            }
+
+            if (found_cache) {
+                /* Flush and close */
+                fsync(fileno(found_cache->handle));
+                fclose(found_cache->handle);
+                std::fill(found_cache->id.uuid, found_cache->id.uuid + sizeof(PlaceHolderId), 0);
+            }
+        }
+
+        this->GetPlaceHolderPath(placeholder_path_out, placeholder_id);
+    }
+
+    Result PlaceHolderAccessor::Create(PlaceHolderId placeholder_id, size_t size) {
+        char placeholder_path[FS_MAX_PATH] = {0};
+
+        this->EnsureRecursively(placeholder_id);
+        this->GetPlaceHolderPathUncached(placeholder_path, placeholder_id);
+
+        R_TRY_CATCH(fsdevCreateFile(placeholder_path, size, FS_CREATE_BIG_FILE)) {
+            R_CATCH(ResultFsPathAlreadyExists) {
+                return ResultNcmPlaceHolderAlreadyExists;
+            }
+        } R_END_TRY_CATCH;
+
+        return ResultSuccess;
+    }
+
+    Result PlaceHolderAccessor::Delete(PlaceHolderId placeholder_id) {
+        char placeholder_path[FS_MAX_PATH] = {0};
+
+        this->GetPlaceHolderPathUncached(placeholder_path, placeholder_id);
+
+        R_TRY_CATCH(fsdevDeleteDirectoryRecursively(placeholder_path)) {
+            R_CATCH(ResultFsPathNotFound) {
+                return ResultNcmPlaceHolderNotFound;
+            }
+        } R_END_TRY_CATCH;
+
+        return ResultSuccess;
+    }
+
+    Result PlaceHolderAccessor::Open(FILE** out_handle, PlaceHolderId placeholder_id) {
+        if (this->LoadFromCache(out_handle, placeholder_id)) {
+            return ResultSuccess;
+        }
+        char placeholder_path[FS_MAX_PATH] = {0};
+
+        this->GetPlaceHolderPath(placeholder_path, placeholder_id);
+        errno = 0;
+        *out_handle = fopen(placeholder_path, "w+b");
+
+        if (errno != 0) {
+            return fsdevGetLastResult();
+        }
+
+        return ResultSuccess;
+    }
+
+    Result PlaceHolderAccessor::SetSize(PlaceHolderId placeholder_id, size_t size) {
+        char placeholder_path[FS_MAX_PATH] = {0};
+        errno = 0;
+        this->GetPlaceHolderPath(placeholder_path, placeholder_id);
+        truncate(placeholder_path, size);
+
+        if (errno != 0) {
+            R_TRY_CATCH(fsdevGetLastResult()) {
+                R_CATCH(ResultFsPathNotFound) {
+                    return ResultNcmPlaceHolderNotFound;
+                }
+            } R_END_TRY_CATCH;
+        }
+
+        return ResultSuccess;
+    }
+
+    Result PlaceHolderAccessor::GetSize(bool* found_in_cache, size_t* out_size, PlaceHolderId placeholder_id) {
+        FILE* f = NULL;
+        
+        /* Set the scope for the scoped_lock. */
+        {
+            std::scoped_lock<HosMutex> lock(this->cache_mutex);
+            
+            if (placeholder_id == InvalidUuid) {
+                *found_in_cache = false;
+                return ResultSuccess;
+            }
+
+            CacheEntry* cache_entry = this->FindInCache(placeholder_id);
+
+            if (cache_entry == nullptr) {
+                *found_in_cache = false;
+                return ResultSuccess;
+            }
+
+            cache_entry->id = InvalidUuid;
+            f = cache_entry->handle;
+        }
+
+        this->FlushCache(f, placeholder_id);
+        
+        errno = 0;
+        fseek(f, 0L, SEEK_END);
+        size_t size = ftell(f);
+        fseek(f, 0L, SEEK_SET);
+
+        if (errno != 0) {
+            return fsdevGetLastResult();
+        }
+
+        *found_in_cache = true;
+        *out_size = size;
+        return ResultSuccess;
+    }
+
+    Result PlaceHolderAccessor::EnsureRecursively(PlaceHolderId placeholder_id) {
+        char placeholder_path[FS_MAX_PATH] = {0};
+        this->GetPlaceHolderPath(placeholder_path, placeholder_id);
+        R_TRY(EnsureParentDirectoryRecursively(placeholder_path));
+        return ResultSuccess;
+    }
+
+    bool PlaceHolderAccessor::LoadFromCache(FILE** out_handle, PlaceHolderId placeholder_id) {
+        std::scoped_lock<HosMutex> lk(this->cache_mutex);
+        CacheEntry *entry = this->FindInCache(placeholder_id);
+        if (entry == nullptr) {
+            return false;
+        }
+        entry->id = InvalidUuid;
+        *out_handle = entry->handle;
+        return true;
+    }
+
+    PlaceHolderAccessor::CacheEntry *PlaceHolderAccessor::FindInCache(PlaceHolderId placeholder_id) {
+        if (placeholder_id == InvalidUuid) {
+            return nullptr;
+        }
+        for (size_t i = 0; i < MaxCaches; i++) {
+            if (placeholder_id == this->caches[i].id) {
+                return &this->caches[i];
+            }
+        }
+        return nullptr;
+    }
+
+    void PlaceHolderAccessor::FlushCache(FILE* handle, PlaceHolderId placeholder_id) {
+        std::scoped_lock<HosMutex> lk(this->cache_mutex);
+        CacheEntry* cache = nullptr;
+
+        /* Find an empty cache */
+        for (size_t i = 0; i < MaxCaches; i++) {
+            if (placeholder_id != InvalidUuid) {
+                cache = &this->caches[i];
+                break;
+            }
+        }
+
+        /* No empty caches found. Let's clear cache 0. */
+        if (cache == nullptr) {
+            cache = &this->caches[0];
+
+            /* Flush and close */
+            fsync(fileno(cache->handle));
+            fclose(cache->handle);
+            cache->id = InvalidUuid;
+        }
+
+        cache->id = placeholder_id;
+        cache->handle = handle;
+        cache->counter = this->cur_counter;
+        this->cur_counter++;
+    }
+
+    void PlaceHolderAccessor::ClearAllCaches() {
+        for (size_t i = 0; i < MaxCaches; i++) {
+            CacheEntry* cache = &this->caches[i];
+
+            if (cache->id != InvalidUuid) {
+                fsync(fileno(cache->handle));
+                fclose(cache->handle);
+                cache->id = InvalidUuid;
+            }
+        }
+    }
+
+}