Add map to windows impl

starboard/shared/win32/posix_emu/dirent.cc

@@ -15,16 +15,88 @@
 #include <dirent.h>
 
 #include <windows.h>
+#include <map>
 
 #include "starboard/common/log.h"
 #include "starboard/common/string.h"
 #include "starboard/configuration_constants.h"
 #include "starboard/shared/win32/directory_internal.h"
 #include "starboard/shared/win32/file_internal.h"
 #include "starboard/shared/win32/wchar_utils.h"
+#include "starboard/types.h"
 
 extern "C" {
 
+struct CriticalSection {
+  CriticalSection() { InitializeCriticalSection(&critical_section_); }
+  CRITICAL_SECTION critical_section_;
+};
+
+static int gen_fd() {
+  static int fd = 100;
+  fd++;
+  if (fd == 0x7FFFFFFF) {
+    fd = 100;
+  }
+  return fd;
+}
+
+static std::map<int, std::deque<std::string>>* directory_map = nullptr;
+static CriticalSection g_critical_section;
+
+int handle_db_put(std::deque<std::string> next_directory_entry) {
+  EnterCriticalSection(&g_critical_section.critical_section_);
+  if (directory_map == nullptr) {
+    directory_map = new std::map<int, std::deque<std::string>>();
+  }
+
+  int fd = gen_fd();
+  // Go through the map and make sure there isn't duplicated index
+  // already.
+  while (directory_map->find(fd) != directory_map->end()) {
+    fd = gen_fd();
+  }
+
+  directory_map->insert({fd, next_directory_entry});
+
+  LeaveCriticalSection(&g_critical_section.critical_section_);
+  return fd;
+}
+
+static std::deque<std::string> handle_db_get(int handle, bool erase) {
+  std::deque<std::string> empty_deque;
+  if (handle < 0) {
+    return empty_deque;
+  }
+  EnterCriticalSection(&g_critical_section.critical_section_);
+  if (directory_map == nullptr) {
+    directory_map = new std::map<int, std::deque<std::string>>();
+    return empty_deque;
+  }
+
+  auto itr = directory_map->find(handle);
+  if (itr == directory_map->end()) {
+    return empty_deque;
+  }
+
+  std::deque<std::string> next_directory_entry = itr->second;
+  if (erase) {
+    directory_map->erase(handle);
+  }
+  LeaveCriticalSection(&g_critical_section.critical_section_);
+  return next_directory_entry;
+}
+
+void handle_db_replace(int fd, std::deque<std::string> next_directory_entry) {
+  EnterCriticalSection(&g_critical_section.critical_section_);
+  if (directory_map == nullptr) {
+    directory_map = new std::map<int, std::deque<std::string>>();
+  }
+  directory_map->erase(fd);
+  directory_map->insert({fd, next_directory_entry});
+  LeaveCriticalSection(&g_critical_section.critical_section_);
+}
+
 DIR* opendir(const char* path) {
   using starboard::shared::win32::CStringToWString;
   using starboard::shared::win32::NormalizeWin32Path;
@@ -59,11 +131,13 @@ DIR* opendir(const char* path) {
 
   DIR* dir = reinterpret_cast<DIR*>(malloc(sizeof(DIR)));
   dir->handle = directory_handle;
+  dir->fd = handle_db_put(std::deque<std::string>());
   return dir;
 }
 
 int closedir(DIR* dir) {
   bool success = CloseHandle(dir->handle);
+  handle_db_get(dir->fd, true);
   delete dir;
   return success ? 0 : -1;
 }
@@ -80,37 +154,41 @@ int readdir_r(DIR* __restrict dir,
     return -1;
   }
 
-  std::deque<std::string> next_directory_entries;
-  alignas(sizeof(DWORDLONG)) std::vector<char> directory_info_buffer(
-      kDirectoryInfoBufferSize);
-  BOOL directory_info_success = GetFileInformationByHandleEx(
-      dir->handle, FileIdBothDirectoryInfo, directory_info_buffer.data(),
-      static_cast<int>(directory_info_buffer.size()));
-
-  if (!directory_info_success) {
-    return -1;
-  }
+  std::deque<std::string> next_directory_entries = handle_db_get(dir->fd, false);
+  if (next_directory_entries.empty()){
+    alignas(sizeof(DWORDLONG)) std::vector<char> directory_info_buffer(
+        kDirectoryInfoBufferSize);
+    BOOL directory_info_success = GetFileInformationByHandleEx(
+        dir->handle, FileIdBothDirectoryInfo, directory_info_buffer.data(),
+        static_cast<int>(directory_info_buffer.size()));
 
-  const char* directory_info_pointer = directory_info_buffer.data();
-  DWORD next_entry_offset = 0;
+    if (!directory_info_success) {
+      return -1;
+    }
 
-  do {
-    auto directory_info = reinterpret_cast<const FILE_ID_BOTH_DIR_INFO*>(
-        directory_info_pointer);
+    const char* directory_info_pointer = directory_info_buffer.data();
+    DWORD next_entry_offset = 0;
+
+    do {
+      auto directory_info = reinterpret_cast<const FILE_ID_BOTH_DIR_INFO*>(
+          directory_info_pointer);
+
+      // FileName is in Unicode, so divide by 2 to get the real length.
+      DWORD number_characters_in_filename = directory_info->FileNameLength / 2;
+      std::string ascii_path = starboard::shared::win32::wchar_tToUTF8(
+          directory_info->FileName, number_characters_in_filename);
+      SB_DCHECK(ascii_path.size() == number_characters_in_filename);
+      bool is_dotted_directory =
+          !ascii_path.compare(".") || !ascii_path.compare("..");
+      if (!is_dotted_directory) {
+        next_directory_entries.emplace_back(std::move(ascii_path));
+      }
+      next_entry_offset = directory_info->NextEntryOffset;
+      directory_info_pointer += next_entry_offset;
+    } while (next_entry_offset != 0);
+    handle_db_replace(dir->fd, next_directory_entries);
+  }
 
-    // FileName is in Unicode, so divide by 2 to get the real length.
-    DWORD number_characters_in_filename = directory_info->FileNameLength / 2;
-    std::string ascii_path = starboard::shared::win32::wchar_tToUTF8(
-        directory_info->FileName, number_characters_in_filename);
-    SB_DCHECK(ascii_path.size() == number_characters_in_filename);
-    bool is_dotted_directory =
-        !ascii_path.compare(".") || !ascii_path.compare("..");
-    if (!is_dotted_directory) {
-      next_directory_entries.emplace_back(std::move(ascii_path));
-    }
-    next_entry_offset = directory_info->NextEntryOffset;
-    directory_info_pointer += next_entry_offset;
-  } while (next_entry_offset != 0);
 
   if (next_directory_entries.empty()) {
     return -1;