ISO build (partial)

src/duskdolphin/asset/assetdolphindvd.c

@@ -0,0 +1,93 @@
+/**
+ * Copyright (c) 2026 Dominic Masters
+ *
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#include "assetdolphindvd.h"
+#include "asset/asset.h"
+#include "util/string.h"
+#include <ogc/dvd.h>
+#include <ogc/cache.h>
+#include <malloc.h>
+
+#define DUSK_DVD_ALIGN 32u
+#define DUSK_DVD_ALIGN_UP(n) \
+  (((u32)(n) + DUSK_DVD_ALIGN - 1u) & ~(DUSK_DVD_ALIGN - 1u))
+
+static u32 dvdBe32(const u8 *p) {
+  return ((u32)p[0] << 24) | ((u32)p[1] << 16) | ((u32)p[2] << 8) | (u32)p[3];
+}
+
+static void *dvdRead(s64 offset, u32 size) {
+  u32 padded = DUSK_DVD_ALIGN_UP(size);
+  void *buf = memalign(DUSK_DVD_ALIGN, padded);
+  if(!buf) return NULL;
+  DCInvalidateRange(buf, padded);
+  dvdcmdblk block;
+  if(DVD_ReadPrio(&block, buf, padded, offset, 0) <= 0) {
+    free(buf);
+    return NULL;
+  }
+  return buf;
+}
+
+errorret_t assetInitDolphin(void) {
+  DVD_Init();
+  DVD_Mount();
+
+  // Read disc header to find FST location
+  u8 *hdr = (u8 *)dvdRead(0, 0x440);
+  if(!hdr) errorThrow("Failed to read DVD disc header.");
+  u32 fstOff  = dvdBe32(hdr + 0x424);
+  u32 fstSize = dvdBe32(hdr + 0x428);
+  free(hdr);
+
+  // Read the FST
+  u8 *fst = (u8 *)dvdRead((s64)fstOff, fstSize);
+  if(!fst) errorThrow("Failed to read DVD FST.");
+
+  // Root entry (index 0) bytes 8-11 = total entry count
+  u32 numEntries = dvdBe32(fst + 8);
+  u8 *strTable   = fst + numEntries * 12u;
+
+  u32 fileOff = 0, fileLen = 0;
+  for(u32 i = 1; i < numEntries; i++) {
+    u8 *e = fst + i * 12u;
+    if(e[0] != 0) continue;
+
+    u32 nameOff = ((u32)e[1] << 16) | ((u32)e[2] << 8) | (u32)e[3];
+    const char_t *name = (const char_t *)(strTable + nameOff);
+    if(stringCompareInsensitive(name, ASSET_FILE_NAME) == 0) {
+      fileOff = dvdBe32(e + 4);
+      fileLen = dvdBe32(e + 8);
+      break;
+    }
+  }
+  free(fst);
+
+  if(!fileOff) errorThrow("Failed to find asset file on DVD.");
+
+  u8 *data = (u8 *)dvdRead((s64)fileOff, fileLen);
+  if(!data) errorThrow("Failed to read asset file from DVD.");
+
+  zip_error_t zerr;
+  zip_source_t *src = zip_source_buffer_create(data, fileLen, 1, &zerr);
+  if(!src) {
+    free(data);
+    errorThrow("Failed to create zip source from DVD buffer.");
+  }
+
+  ASSET.zip = zip_open_from_source(src, ZIP_RDONLY, &zerr);
+  if(!ASSET.zip) {
+    zip_source_free(src);
+    errorThrow("Failed to open asset zip from DVD.");
+  }
+
+  errorOk();
+}
+
+errorret_t assetDisposeDolphin(void) {
+  errorOk();
+}