Save file update (incomplete)

src/duskdolphin/save/savestreamdolphin.c

@@ -0,0 +1,112 @@
+/**
+ * Copyright (c) 2026 Dominic Masters
+ *
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#include "save/save.h"
+#include "save/savestreamdolphin.h"
+#include "util/memory.h"
+#include "util/string.h"
+
+static void _saveStreamGetFileName(
+  char_t *out, const size_t max, const uint8_t slot
+) {
+  snprintf(out, max, "%s_%u", SAVE_DOLPHIN_GAME_CODE, (uint32_t)slot);
+}
+
+errorret_t saveStreamOpenReadDolphin(
+  savestreamdolphin_t *p, bool_t *found, const uint8_t slot
+) {
+  char_t fileName[SAVE_DOLPHIN_FILE_NAME_MAX];
+  _saveStreamGetFileName(fileName, SAVE_DOLPHIN_FILE_NAME_MAX, slot);
+
+  int32_t result = CARD_Open(
+    SAVE_DOLPHIN_CHANNEL, fileName, &p->cardFile
+  );
+  if(result == CARD_ERROR_NOFILE) {
+    *found = false;
+    p->position = 0;
+    p->writing = false;
+    errorOk();
+  }
+  if(result < 0) {
+    *found = false;
+    errorThrow("Failed to open memory card file for slot %u (error %d)",
+      (uint32_t)slot, result
+    );
+  }
+
+  result = CARD_Read(&p->cardFile, p->buffer, SAVE_DOLPHIN_SECTOR_SIZE, 0);
+  CARD_Close(&p->cardFile);
+  if(result < 0) {
+    *found = false;
+    errorThrow("Failed to read memory card data for slot %u (error %d)",
+      (uint32_t)slot, result
+    );
+  }
+
+  *found = true;
+  p->position = 0;
+  p->writing = false;
+  p->slot = slot;
+  errorOk();
+}
+
+errorret_t saveStreamOpenWriteDolphin(
+  savestreamdolphin_t *p, const uint8_t slot
+) {
+  memoryZero(p->buffer, SAVE_DOLPHIN_SECTOR_SIZE);
+  p->position = 0;
+  p->writing = true;
+  p->slot = slot;
+  errorOk();
+}
+
+void saveStreamCloseDolphin(savestreamdolphin_t *p) {
+  if(!p->writing) return;
+
+  char_t fileName[SAVE_DOLPHIN_FILE_NAME_MAX];
+  _saveStreamGetFileName(fileName, SAVE_DOLPHIN_FILE_NAME_MAX, p->slot);
+
+  int32_t result = CARD_Open(SAVE_DOLPHIN_CHANNEL, fileName, &p->cardFile);
+  if(result == CARD_ERROR_NOFILE) {
+    CARD_Create(
+      SAVE_DOLPHIN_CHANNEL, fileName, SAVE_DOLPHIN_SECTOR_SIZE, &p->cardFile
+    );
+  }
+
+  CARD_Write(&p->cardFile, p->buffer, SAVE_DOLPHIN_SECTOR_SIZE, 0);
+  CARD_Close(&p->cardFile);
+}
+
+errorret_t saveStreamReadBytesDolphin(
+  savestreamdolphin_t *p, void *buf, const size_t len
+) {
+  if(p->position + len > SAVE_DOLPHIN_SECTOR_SIZE) {
+    errorThrow("Save stream read exceeds sector size");
+  }
+  memoryCopy(buf, p->buffer + p->position, len);
+  p->position += len;
+  errorOk();
+}
+
+errorret_t saveStreamWriteBytesDolphin(
+  savestreamdolphin_t *p, const void *buf, const size_t len
+) {
+  if(p->position + len > SAVE_DOLPHIN_SECTOR_SIZE) {
+    errorThrow("Save stream write exceeds sector size");
+  }
+  memoryCopy(p->buffer + p->position, buf, len);
+  p->position += len;
+  errorOk();
+}
+
+errorret_t saveStreamSeekDolphin(savestreamdolphin_t *p, const size_t pos) {
+  if(pos >= SAVE_DOLPHIN_SECTOR_SIZE) {
+    errorThrow("Save stream seek out of range");
+  }
+  p->position = pos;
+  errorOk();
+}