Adding support for disc images.

With this, games can now be loaded! Of course, prep fails.

include/xenia/core/mmap.h

@@ -25,7 +25,7 @@ xe_mmap_ref xe_mmap_open(xe_pal_ref pal, const xe_file_mode mode,
                          const size_t offset, const size_t length);
 xe_mmap_ref xe_mmap_retain(xe_mmap_ref mmap);
 void xe_mmap_release(xe_mmap_ref mmap);
-void *xe_mmap_get_addr(xe_mmap_ref mmap);
+uint8_t* xe_mmap_get_addr(xe_mmap_ref mmap);
 size_t xe_mmap_get_length(xe_mmap_ref mmap);
 
 

src/core/mmap_posix.cc

@@ -92,8 +92,8 @@ void xe_mmap_release(xe_mmap_ref mmap) {
   xe_ref_release((xe_ref)mmap, (xe_ref_dealloc_t)xe_mmap_dealloc);
 }
 
-void* xe_mmap_get_addr(xe_mmap_ref mmap) {
-  return mmap->addr;
+uint8_t* xe_mmap_get_addr(xe_mmap_ref mmap) {
+  return (uint8_t*)mmap->addr;
 }
 
 size_t xe_mmap_get_length(xe_mmap_ref mmap) {

src/core/mmap_win.cc

@@ -89,7 +89,7 @@ xe_mmap_ref xe_mmap_open(xe_pal_ref pal, const xe_file_mode mode,
     size_t map_length = GetFileSize(file_handle, NULL);
     mmap->length = map_length;
   }
-  
+
   return mmap;
 
 XECLEANUP:
@@ -123,7 +123,7 @@ void xe_mmap_release(xe_mmap_ref mmap) {
   xe_ref_release((xe_ref)mmap, (xe_ref_dealloc_t)xe_mmap_dealloc);
 }
 
-void* xe_mmap_get_addr(xe_mmap_ref mmap) {
+uint8_t* xe_mmap_get_addr(xe_mmap_ref mmap) {
   return mmap->addr;
 }
 

src/kernel/fs/devices/disc_image_device.cc

@@ -9,22 +9,105 @@
 
 #include "kernel/fs/devices/disc_image_device.h"
 
+#include "kernel/fs/gdfx.h"
+
 
 using namespace xe;
 using namespace xe::kernel;
 using namespace xe::kernel::fs;
 
 
+namespace {
+
+
+class DiscImageMemoryMapping : public MemoryMapping {
+public:
+  DiscImageMemoryMapping(uint8_t* address, size_t length, xe_mmap_ref mmap) :
+      MemoryMapping(address, length) {
+    mmap_ = xe_mmap_retain(mmap);
+  }
+
+  virtual ~DiscImageMemoryMapping() {
+    xe_mmap_release(mmap_);
+  }
+
+private:
+  xe_mmap_ref mmap_;
+};
+
+
+class DiscImageFileEntry : public FileEntry {
+public:
+  DiscImageFileEntry(Device* device, const char* path,
+                     xe_mmap_ref mmap, GDFXEntry* gdfx_entry) :
+      FileEntry(device, path),
+      gdfx_entry_(gdfx_entry) {
+    mmap_ = xe_mmap_retain(mmap);
+  }
+
+  virtual ~DiscImageFileEntry() {
+    delete gdfx_entry_;
+    xe_mmap_release(mmap_);
+  }
+
+  virtual MemoryMapping* CreateMemoryMapping(
+      xe_file_mode file_mode, const size_t offset, const size_t length) {
+    if (file_mode & kXEFileModeWrite) {
+      // Only allow reads.
+      return NULL;
+    }
+
+    size_t real_offset = gdfx_entry_->offset + offset;
+    size_t real_length = length ?
+        MIN(length, gdfx_entry_->size) : gdfx_entry_->size;
+    return new DiscImageMemoryMapping(
+        xe_mmap_get_addr(mmap_) + real_offset,
+        real_length,
+        mmap_);
+  }
+
+private:
+  xe_mmap_ref mmap_;
+  GDFXEntry*  gdfx_entry_;
+};
+
+
+}
+
+
 DiscImageDevice::DiscImageDevice(xe_pal_ref pal, const char* path,
                                  const xechar_t* local_path) :
     Device(pal, path) {
   local_path_ = xestrdup(local_path);
+  mmap_ = NULL;
+  gdfx_ = NULL;
 }
 
 DiscImageDevice::~DiscImageDevice() {
+  delete gdfx_;
+  xe_mmap_release(mmap_);
   xe_free(local_path_);
 }
 
+int DiscImageDevice::Init() {
+  mmap_ = xe_mmap_open(pal_, kXEFileModeRead, local_path_, 0, 0);
+  if (!mmap_) {
+    XELOGE(XT("Disc image could not be mapped"));
+    return 1;
+  }
+
+  gdfx_ = new GDFX(mmap_);
+  GDFX::Error error = gdfx_->Load();
+  if (error != GDFX::kSuccess) {
+    XELOGE(XT("GDFX init failed: %d"), error);
+    return 1;
+  }
+
+  //gdfx_->Dump();
+
+  return 0;
+}
+
 Entry* DiscImageDevice::ResolvePath(const char* path) {
   // The filesystem will have stripped our prefix off already, so the path will
   // be in the form:
@@ -32,5 +115,44 @@ Entry* DiscImageDevice::ResolvePath(const char* path) {
 
   XELOGFS(XT("DiscImageDevice::ResolvePath(%s)"), path);
 
-  return NULL;
+  GDFXEntry* gdfx_entry = gdfx_->root_entry();
+
+  // Walk the path, one separator at a time.
+  // We copy it into the buffer and shift it left over and over.
+  char remaining[XE_MAX_PATH];
+  XEIGNORE(xestrcpya(remaining, XECOUNT(remaining), path));
+  while (remaining[0]) {
+    char* next_slash = xestrchra(remaining, '\\');
+    if (next_slash == remaining) {
+      // Leading slash - shift
+      XEIGNORE(xestrcpya(remaining, XECOUNT(remaining), remaining + 1));
+      continue;
+    }
+
+    // Make the buffer just the name.
+    if (next_slash) {
+      *next_slash = 0;
+    }
+
+    // Look up in the entry.
+    gdfx_entry = gdfx_entry->GetChild(remaining);
+    if (!gdfx_entry) {
+      // Not found.
+      return NULL;
+    }
+
+    // Shift the buffer down, unless we are at the end.
+    if (!next_slash) {
+      break;
+    }
+    XEIGNORE(xestrcpya(remaining, XECOUNT(remaining), next_slash + 1));
+  }
+
+  if (gdfx_entry->attributes & GDFXEntry::kAttrFolder) {
+    //return new DiscImageDirectoryEntry(mmap_, gdfx_entry);
+    XEASSERTALWAYS();
+    return NULL;
+  } else {
+    return new DiscImageFileEntry(this, path, mmap_, gdfx_entry);
+  }
 }

src/kernel/fs/devices/disc_image_device.h

@@ -21,15 +21,22 @@ namespace kernel {
 namespace fs {
 
 
+class GDFX;
+
+
 class DiscImageDevice : public Device {
 public:
   DiscImageDevice(xe_pal_ref pal, const char* path, const xechar_t* local_path);
   virtual ~DiscImageDevice();
 
+  int Init();
+
   virtual Entry* ResolvePath(const char* path);
 
 private:
   xechar_t*   local_path_;
+  xe_mmap_ref mmap_;
+  GDFX*       gdfx_;
 };
 
 

src/kernel/fs/filesystem.cc

@@ -48,7 +48,10 @@ int FileSystem::RegisterLocalDirectoryDevice(
 
 int FileSystem::RegisterDiscImageDevice(
     const char* path, const xechar_t* local_path) {
-  Device* device = new DiscImageDevice(pal_, path, local_path);
+  DiscImageDevice* device = new DiscImageDevice(pal_, path, local_path);
+  if (device->Init()) {
+    return 1;
+  }
   return RegisterDevice(path, device);
 }
 

src/kernel/fs/gdfx.cc

@@ -0,0 +1,207 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2013 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ * Major contributions to this file from:
+ * - abgx360
+ */
+
+#include "kernel/fs/gdfx.h"
+
+
+using namespace xe;
+using namespace xe::kernel;
+using namespace xe::kernel::fs;
+
+
+namespace {
+
+#define kXESectorSize   2048
+
+}
+
+
+GDFXEntry::~GDFXEntry() {
+  for (std::vector<GDFXEntry*>::iterator it = children.begin();
+       it != children.end(); ++it) {
+    delete *it;
+  }
+}
+
+GDFXEntry* GDFXEntry::GetChild(const char* name) {
+  // TODO(benvanik): a faster search
+  for (std::vector<GDFXEntry*>::iterator it = children.begin();
+       it != children.end(); ++it) {
+    GDFXEntry* entry = *it;
+    if (xestrcasecmpa(entry->name.c_str(), name) == 0) {
+      return entry;
+    }
+  }
+  return NULL;
+}
+
+void GDFXEntry::Dump(int indent) {
+  printf("%s%s\n", std::string(indent, ' ').c_str(), name.c_str());
+  for (std::vector<GDFXEntry*>::iterator it = children.begin();
+       it != children.end(); ++it) {
+    GDFXEntry* entry = *it;
+    entry->Dump(indent + 2);
+  }
+}
+
+
+GDFX::GDFX(xe_mmap_ref mmap) {
+  mmap_ = xe_mmap_retain(mmap);
+
+  root_entry_ = NULL;
+}
+
+GDFX::~GDFX() {
+  delete root_entry_;
+
+  xe_mmap_release(mmap_);
+}
+
+GDFXEntry* GDFX::root_entry() {
+  return root_entry_;
+}
+
+GDFX::Error GDFX::Load() {
+  Error result = kErrorOutOfMemory;
+
+  ParseState state;
+  xe_zero_struct(&state, sizeof(state));
+
+  state.ptr   = (uint8_t*)xe_mmap_get_addr(mmap_);
+  state.size  = xe_mmap_get_length(mmap_);
+
+  result = Verify(state);
+  XEEXPECTZERO(result);
+
+  result = ReadAllEntries(state, state.ptr + state.root_offset);
+  XEEXPECTZERO(result);
+
+  result = kSuccess;
+XECLEANUP:
+  return result;
+}
+
+void GDFX::Dump() {
+  if (root_entry_) {
+    root_entry_->Dump(0);
+  }
+}
+
+GDFX::Error GDFX::Verify(ParseState& state) {
+  // Find sector 32 of the game partition - try at a few points.
+  const static size_t likely_offsets[] = {
+    0x00000000, 0x0000FB20, 0x00020600, 0x0FD90000,
+  };
+  bool magic_found = false;
+  for (size_t n = 0; n < XECOUNT(likely_offsets); n++) {
+    state.game_offset = likely_offsets[n];
+    if (VerifyMagic(state, state.game_offset + (32 * kXESectorSize))) {
+      magic_found = true;
+      break;
+    }
+  }
+  if (!magic_found) {
+    // File doesn't have the magic values - likely not a real GDFX source.
+    return kErrorFileMismatch;
+  }
+
+  // Read sector 32 to get FS state.
+  if (state.size < state.game_offset + (32 * kXESectorSize)) {
+    return kErrorReadError;
+  }
+  uint8_t* fs_ptr = state.ptr + state.game_offset + (32 * kXESectorSize);
+  state.root_sector = XEGETUINT32LE(fs_ptr + 20);
+  state.root_size   = XEGETUINT32LE(fs_ptr + 24);
+  state.root_offset = state.game_offset + (state.root_sector * kXESectorSize);
+  if (state.root_size < 13 ||
+      state.root_size > 32 * 1024 * 1024) {
+    return kErrorDamagedFile;
+  }
+
+  return kSuccess;
+}
+
+bool GDFX::VerifyMagic(ParseState& state, size_t offset) {
+  // Simple check to see if the given offset contains the magic value.
+  return memcmp(state.ptr + offset, "MICROSOFT*XBOX*MEDIA", 20) == 0;
+}
+
+GDFX::Error GDFX::ReadAllEntries(ParseState& state,
+                                 const uint8_t* root_buffer) {
+  root_entry_ = new GDFXEntry();
+  root_entry_->offset = 0;
+  root_entry_->size   = 0;
+  root_entry_->name   = "";
+  root_entry_->attributes = GDFXEntry::kAttrFolder;
+
+  if (!ReadEntry(state, root_buffer, 0, root_entry_)) {
+    return kErrorOutOfMemory;
+  }
+
+  return kSuccess;
+}
+
+bool GDFX::ReadEntry(ParseState& state, const uint8_t* buffer,
+                     uint16_t entry_ordinal, GDFXEntry* parent) {
+  const uint8_t* p = buffer + (entry_ordinal * 4);
+
+  uint16_t  node_l      = XEGETUINT16LE(p + 0);
+  uint16_t  node_r      = XEGETUINT16LE(p + 2);
+  size_t    sector      = XEGETUINT32LE(p + 4);
+  size_t    length      = XEGETUINT32LE(p + 8);
+  uint8_t   attributes  = XEGETUINT8LE(p + 12);
+  uint8_t   name_length = XEGETUINT8LE(p + 13);
+  char*     name        = (char*)(p + 14);
+
+  if (node_l && !ReadEntry(state, buffer, node_l, parent)) {
+    return false;
+  }
+
+  GDFXEntry* entry = new GDFXEntry();
+  entry->name = std::string(name, name_length);
+  entry->name.append(1, '\0');
+  entry->attributes = attributes;
+
+  // Add to parent (if we have one).
+  if (parent) {
+    parent->children.push_back(entry);
+  }
+
+  if (attributes & GDFXEntry::kAttrFolder) {
+    // Folder.
+    entry->offset = 0;
+    entry->size   = 0;
+    if (length) {
+      // Not a leaf - read in children.
+      if (state.size < state.game_offset + (sector * kXESectorSize)) {
+        // Out of bounds read.
+        return false;
+      }
+      // Read child list.
+      uint8_t* folder_ptr =
+          state.ptr + state.game_offset + (sector * kXESectorSize);
+      if (!ReadEntry(state, folder_ptr, 0, entry)) {
+        return false;
+      }
+    }
+  } else {
+    // File.
+    entry->offset = state.game_offset + (sector * kXESectorSize);
+    entry->size   = length;
+  }
+
+  // Read next file in the list.
+  if (node_r && !ReadEntry(state, buffer, node_r, parent)) {
+    return false;
+  }
+
+  return true;
+}

src/kernel/fs/gdfx.h

@@ -0,0 +1,105 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2013 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#ifndef XENIA_KERNEL_FS_GDFX_H_
+#define XENIA_KERNEL_FS_GDFX_H_
+
+#include <xenia/common.h>
+#include <xenia/core.h>
+
+#include <vector>
+
+#include <xenia/kernel/fs/entry.h>
+
+
+namespace xe {
+namespace kernel {
+namespace fs {
+
+
+class GDFX;
+
+
+class GDFXEntry {
+public:
+  enum Attributes {
+    kAttrNone       = 0x00000000,
+    kAttrReadOnly   = 0x00000001,
+    kAttrHidden     = 0x00000002,
+    kAttrSystem     = 0x00000004,
+    kAttrFolder     = 0x00000010,
+    kAttrArchived   = 0x00000020,
+    kAttrNormal     = 0x00000080,
+  };
+
+  GDFXEntry() {}
+  ~GDFXEntry();
+
+  GDFXEntry* GetChild(const char* name);
+
+  void Dump(int indent);
+
+  std::string   name;
+  uint32_t      attributes;
+  size_t        offset;
+  size_t        size;
+
+  std::vector<GDFXEntry*> children;
+};
+
+
+class GDFX {
+public:
+  enum Error {
+    kSuccess            = 0,
+    kErrorOutOfMemory   = -1,
+    kErrorReadError     = -10,
+    kErrorFileMismatch  = -30,
+    kErrorDamagedFile   = -31,
+  };
+
+  GDFX(xe_mmap_ref mmap);
+  virtual ~GDFX();
+
+  GDFXEntry* root_entry();
+
+  Error Load();
+  void Dump();
+
+private:
+  typedef struct {
+    uint8_t*  ptr;
+
+    size_t    size;           // Size (bytes) of total image
+
+    size_t    game_offset;    // Offset (bytes) of game partition
+
+    size_t    root_sector;    // Offset (sector) of root
+    size_t    root_offset;    // Offset (bytes) of root
+    size_t    root_size;      // Size (bytes) of root
+  } ParseState;
+
+  Error Verify(ParseState& state);
+  bool VerifyMagic(ParseState& state, size_t offset);
+  Error ReadAllEntries(ParseState& state, const uint8_t* root_buffer);
+  bool ReadEntry(ParseState& state, const uint8_t* buffer,
+                 uint16_t entry_ordinal, GDFXEntry* parent);
+
+  xe_mmap_ref mmap_;
+
+  GDFXEntry*  root_entry_;
+};
+
+
+}  // namespace fs
+}  // namespace kernel
+}  // namespace xe
+
+
+#endif  // XENIA_KERNEL_FS_GDFX_H_

src/kernel/fs/sources.gypi

@@ -4,6 +4,7 @@
     'device.cc',
     'entry.cc',
     'filesystem.cc',
+    'gdfx.cc',
   ],
 
   'includes': [