Huge savedata driver refactor

bdk/libs/nx_savedata/duplex_storage.c

@@ -0,0 +1,108 @@
+/*
+ * 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 "duplex_storage.h"
+
+#include <gfx_utils.h>
+#include <mem/heap.h>
+
+void save_duplex_storage_init(duplex_storage_ctx_t *ctx, uint8_t *data_a, uint8_t *data_b, uint32_t block_size_power, void *bitmap, uint64_t bitmap_size) {
+    substorage_init(&ctx->data_a, &memory_storage_vt, data_a, 0, ctx->_length);
+    substorage_init(&ctx->data_b, &memory_storage_vt, data_b, 0, ctx->_length);
+    substorage_init(&ctx->bitmap_storage, &memory_storage_vt, bitmap, 0, bitmap_size);
+    ctx->block_size = 1 << block_size_power;
+
+    ctx->bitmap.data = (uint8_t *)bitmap;
+    ctx->bitmap.bitmap = malloc(bitmap_size >> 3);
+
+    uint32_t bits_remaining = (uint32_t)bitmap_size;
+    uint32_t bitmap_pos = 0;
+    uint32_t *buffer_pos = (uint32_t *)ctx->bitmap.data;
+    while (bits_remaining) {
+        uint32_t bits_to_read = MIN(bits_remaining, 0x20);
+        uint32_t val = *buffer_pos;
+        for (uint32_t i = 0; i < bits_to_read; i++) {
+            if (val & 0x80000000)
+                save_bitmap_set_bit(ctx->bitmap.bitmap, bitmap_pos);
+            else
+                save_bitmap_clear_bit(ctx->bitmap.bitmap, bitmap_pos);
+            bitmap_pos++;
+            bits_remaining--;
+            val <<= 1;
+        }
+        buffer_pos++;
+    }
+}
+
+uint32_t save_duplex_storage_read(duplex_storage_ctx_t *ctx, void *buffer, uint64_t offset, uint64_t count) {
+    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);
+        uint32_t block_pos = (uint32_t)(in_pos % ctx->block_size);
+        uint32_t bytes_to_read = MIN(ctx->block_size - block_pos, remaining);
+
+        substorage *data = save_bitmap_check_bit(ctx->bitmap.bitmap, block_num) ? &ctx->data_b : &ctx->data_a;
+        if (substorage_read(data, (uint8_t *)buffer + out_pos, in_pos, 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_duplex_storage_write(duplex_storage_ctx_t *ctx, const void *buffer, uint64_t offset, uint64_t count) {
+    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);
+        uint32_t block_pos = (uint32_t)(in_pos % ctx->block_size);
+        uint32_t bytes_to_write = MIN(ctx->block_size - block_pos, remaining);
+
+        substorage *data = save_bitmap_check_bit(ctx->bitmap.bitmap, block_num) ? &ctx->data_b : &ctx->data_a;
+        if (substorage_write(data, (uint8_t *)buffer + out_pos, in_pos, 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;
+}