rpc example for directory file listing

runtime/bin/directory_exp.cc

Index: runtime/bin/directory_exp.cc
diff --git a/runtime/bin/directory_exp.cc b/runtime/bin/directory_exp.cc
new file mode 100644
index 0000000000000000000000000000000000000000..32c684f798fe9f2f7501894b9518b7a5af80516d
--- /dev/null
+++ b/runtime/bin/directory_exp.cc
@@ -0,0 +1,109 @@
+// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// experimental - do not submit
+
+#include <errno.h>
+#include <dirent.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include "bin/dartutils.h"
+#include "include/dart_api.h"
+
+void PrintString(Dart_Handle strHandle) {
+  const char *cstring;
+  Dart_StringToCString(strHandle, &cstring);
+  printf("%s\n", cstring);
+}
+
+void PrintHandle(Dart_Handle handle) {
+  PrintString(Dart_ToString(handle));
+}
+
+static void handleErrorNumber(Dart_NativeArguments args, int error_number);
+
+void FUNCTION_NAME(FilePath_List)(Dart_NativeArguments args) {
+  Dart_EnterScope();
+  printf("FilePath_List\n");
+  ASSERT(Dart_GetNativeArgumentCount(args) == 1);
+
+  const char *path = NULL;
+  Dart_StringToCString(Dart_GetNativeArgument(args, 0), &path);
+
+  DIR* dir_pointer = opendir(path);
+  if (!dir_pointer) {
+    handleErrorNumber(args, errno);
+  } else {
+    const int MAX_ENTRY = 1000;  // TODO(mattsh) - use growable array or vector
+    Dart_Handle names[MAX_ENTRY];
+    int name_index = 0;
+    dirent entry;
+    while (true) {
+      if (name_index >= MAX_ENTRY) {
+        break;
+      }
+      dirent* result;
+      int error_number = readdir_r(dir_pointer, &entry, &result);
+      if (error_number) {
+        handleErrorNumber(args, error_number);
+        break;
+      }
+      if (!result) {
+        break;
+      }
+      if (!strcmp(entry.d_name, ".") || !strcmp(entry.d_name, "..")) {
+        continue;
+      }
+      names[name_index++] = Dart_NewString(entry.d_name);
+    }
+    Dart_Handle name_list = Dart_NewList(name_index);
+    for (int i = 0; i < name_index; i++) {
+      Dart_ListSetAt(name_list, i, names[i]);
+    }
+    Dart_SetReturnValue(args, name_list);
+  }
+  Dart_ExitScope();
+}
+
+void FUNCTION_NAME(FilePath_IsDirectory)(Dart_NativeArguments args) {
+  Dart_EnterScope();
+  printf("FilePath_IsDirectory\n");
+  ASSERT(Dart_GetNativeArgumentCount(args) == 1);
+
+  const char *path = NULL;
+  Dart_StringToCString(Dart_GetNativeArgument(args, 0), &path);
+
+  struct stat entry_info;
+  int lstat_success = lstat(path, &entry_info);
+  if (lstat_success != 0) {
+    handleErrorNumber(args, errno);
+  } else {
+    bool isDirectory = false;
+    if ((entry_info.st_mode & S_IFMT) == S_IFDIR) {
+      isDirectory = true;
+    }
+    Dart_SetReturnValue(args, Dart_NewBoolean(isDirectory));
+  }
+  Dart_ExitScope();
+}
+
+void handleErrorNumber(Dart_NativeArguments args, int error_number) {
+    const char *message;
+    const int MAX_LEN = 100;
+    char message_buffer[MAX_LEN];
+    switch (error_number) {
+      case ENOENT:
+        message = "No such file or directory";
+        break;
+      case ENAMETOOLONG:
+        message = "File name too long";
+        break;
+      default:
+        snprintf(message_buffer, MAX_LEN, "TODO - errno %d", errno);
+        message = message_buffer;
+        break;
+    }
+    Dart_SetReturnValue(args, Dart_NewString(message));
+}