Huge savedata driver refactor

bdk/libs/nx_savedata/allocation_table_storage.c

@@ -0,0 +1,158 @@
+/*
+ * Copyright (c) 2019-2020 shchmue
+ *
+ * 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/>.
+ */
+
+/*
+ISC License
+
+hactool Copyright (c) 2018, SciresM
+
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "allocation_table_storage.h"
+
+#include "allocation_table_iterator.h"
+
+#include <gfx_utils.h>
+
+void save_allocation_table_storage_init(allocation_table_storage_ctx_t *ctx, substorage *data, allocation_table_ctx_t *table, uint32_t block_size, uint32_t initial_block) {
+    ctx->base_storage = data;
+    ctx->block_size = block_size;
+    ctx->fat = table;
+    ctx->initial_block = initial_block;
+    ctx->_length = initial_block == 0xFFFFFFFF ? 0 : save_allocation_table_get_list_length(table, initial_block) * block_size;
+}
+
+uint32_t save_allocation_table_storage_read(allocation_table_storage_ctx_t *ctx, void *buffer, uint64_t offset, uint64_t count) {
+    allocation_table_iterator_ctx_t iterator;
+    if (!save_allocation_table_iterator_begin(&iterator, ctx->fat, ctx->initial_block))
+        return 0;
+    uint64_t in_pos = offset;
+    uint32_t out_pos = 0;
+    uint32_t remaining = count;
+
+    while (remaining) {
+        uint32_t block_num = (uint32_t)(in_pos / ctx->block_size);
+        if (!save_allocation_table_iterator_seek(&iterator, block_num)) {
+            EPRINTFARGS("Invalid allocation table offset: %x", (uint32_t)offset);
+            return 0;
+        }
+
+        uint32_t segment_pos = (uint32_t)(in_pos - (uint64_t)iterator.virtual_block * ctx->block_size);
+        uint64_t physical_offset = iterator.physical_block * ctx->block_size + segment_pos;
+
+        uint32_t remaining_in_segment = iterator.current_segment_size * ctx->block_size - segment_pos;
+        uint32_t bytes_to_read = MIN(remaining, remaining_in_segment);
+
+        if (substorage_read(ctx->base_storage, (uint8_t *)buffer + out_pos, physical_offset, bytes_to_read) != bytes_to_read)
+            return 0;
+
+        out_pos += bytes_to_read;
+        in_pos += bytes_to_read;
+        remaining -= bytes_to_read;
+    }
+    return out_pos;
+}
+
+uint32_t save_allocation_table_storage_write(allocation_table_storage_ctx_t *ctx, const void *buffer, uint64_t offset, uint64_t count) {
+    allocation_table_iterator_ctx_t iterator;
+    if (!save_allocation_table_iterator_begin(&iterator, ctx->fat, ctx->initial_block))
+        return 0;
+    uint64_t in_pos = offset;
+    uint32_t out_pos = 0;
+    uint32_t remaining = count;
+
+    while (remaining) {
+        uint32_t block_num = (uint32_t)(in_pos / ctx->block_size);
+        if (!save_allocation_table_iterator_seek(&iterator, block_num)) {
+            EPRINTFARGS("Invalid allocation table offset: %x", (uint32_t)offset);
+            return 0;
+        }
+
+        uint32_t segment_pos = (uint32_t)(in_pos - (uint64_t)iterator.virtual_block * ctx->block_size);
+        uint64_t physical_offset = iterator.physical_block * ctx->block_size + segment_pos;
+
+        uint32_t remaining_in_segment = iterator.current_segment_size * ctx->block_size - segment_pos;
+        uint32_t bytes_to_write = MIN(remaining, remaining_in_segment);
+
+
+        if (substorage_write(ctx->base_storage, (uint8_t *)buffer + out_pos, physical_offset, bytes_to_write) != bytes_to_write)
+            return 0;
+
+        out_pos += bytes_to_write;
+        in_pos += bytes_to_write;
+        remaining -= bytes_to_write;
+    }
+    return out_pos;
+}
+
+bool save_allocation_table_storage_set_size(allocation_table_storage_ctx_t *ctx, uint64_t size) {
+    uint32_t old_block_count = (uint32_t)DIV_ROUND_UP(ctx->_length, ctx->block_size);
+    uint32_t new_block_count = (uint32_t)DIV_ROUND_UP(size, ctx->block_size);
+
+    if (old_block_count == new_block_count)
+        return true;
+
+    if (old_block_count == 0) {
+        ctx->initial_block = save_allocation_table_allocate(ctx->fat, new_block_count);
+        if (ctx->initial_block == 0xFFFFFFFF) {
+            EPRINTF("Not enough space to resize file!");
+            return false;
+        }
+        ctx->_length = new_block_count * ctx->block_size;
+        return true;
+    }
+
+    if (new_block_count == 0) {
+        save_allocation_table_free(ctx->fat, ctx->initial_block);
+
+        ctx->initial_block = 0x80000000;
+        ctx->_length = 0;
+        return true;
+    }
+
+    if (new_block_count > old_block_count) {
+        uint32_t new_blocks = save_allocation_table_allocate(ctx->fat, new_block_count - old_block_count);
+        if (new_blocks == 0xFFFFFFFF) {
+            EPRINTF("Not enough space to resize file!");
+            return false;
+        }
+        if (!save_allocation_table_join(ctx->fat, ctx->initial_block, new_blocks))
+            return false;
+    } else {
+        uint32_t old_blocks = save_allocation_table_trim(ctx->fat, ctx->initial_block, new_block_count);
+        if (old_blocks == 0xFFFFFFFF) {
+            EPRINTF("Failure to trim!");
+            return false;
+        }
+        if (!save_allocation_table_free(ctx->fat, old_blocks))
+            return false;
+    }
+
+    ctx->_length = new_block_count * ctx->block_size;
+
+    return true;
+}