- Implement a first cut for const String.env in the VM to allow

runtime/bin/main.cc

 // Copyright (c) 2012, 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.
 
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 
 #include "include/dart_api.h"
 #include "include/dart_debugger_api.h"
@@ skipping 404 matching lines @@
 #define CHECK_RESULT(result)                                                   \
   if (Dart_IsError(result)) {                                                  \
     *error = strdup(Dart_GetError(result));                                    \
     *is_compile_error = Dart_IsCompilationError(result);                       \
     Dart_ExitScope();                                                          \
     Dart_ShutdownIsolate();                                                    \
     return NULL;                                                               \
   }                                                                            \
 
 
+static Dart_Handle EnvironmentCallback(Dart_EnvironmentType type,
+                                       Dart_Handle name) {
+  uint8_t* utf8_array;
+  intptr_t utf8_len;
+  Dart_Handle result = Dart_Null();
+  Dart_Handle handle = Dart_StringToUTF8(name, &utf8_array, &utf8_len);
+  if (Dart_IsError(handle)) {
+    handle = Dart_ThrowException(
+        DartUtils::NewDartArgumentError(Dart_GetError(handle)));
+  } else {
+    char* name_chars = reinterpret_cast<char*>(malloc(utf8_len + 1));
+    memmove(name_chars, utf8_array, utf8_len);
+    name_chars[utf8_len] = '\0';
+    const char* value = getenv(name_chars);
+    if (value != NULL) {
+      if ((type == kStringEnvironment) || (type == kIntegerEnvironment)) {
+        result = Dart_NewStringFromUTF8(reinterpret_cast<const uint8_t*>(value),
+                                        strlen(value));
+      } else if (type == kBoolEnvironment) {
+        if (strcmp(value, "true") == 0) {
+          result = Dart_True();
+        } else {
+          result = Dart_False();
+        }
+      }
+    }
+  }
+  return result;
+}
+
+
 // Returns true on success, false on failure.
 static Dart_Isolate CreateIsolateAndSetupHelper(const char* script_uri,
                                                 const char* main,
                                                 void* data,
                                                 char** error,
                                                 bool* is_compile_error) {
   Dart_Isolate isolate =
       Dart_CreateIsolate(script_uri, main, snapshot_buffer, data, error);
   if (isolate == NULL) {
     return NULL;
   }
 
   Dart_EnterScope();
 
   if (snapshot_buffer != NULL) {
     // Setup the native resolver as the snapshot does not carry it.
     Builtin::SetNativeResolver(Builtin::kBuiltinLibrary);
     Builtin::SetNativeResolver(Builtin::kIOLibrary);
   }
 
   // Set up the library tag handler for this isolate.
   Dart_Handle result = Dart_SetLibraryTagHandler(DartUtils::LibraryTagHandler);
   CHECK_RESULT(result);
 
+  result = Dart_SetEnvironmentCallback(EnvironmentCallback);
+  CHECK_RESULT(result);
+
   // Load the specified application script into the newly created isolate.
 
   // Prepare builtin and its dependent libraries for use to resolve URIs.
   // The builtin library is part of the core snapshot and would already be
   // available here in the case of script snapshot loading.
   Dart_Handle builtin_lib =
       Builtin::LoadAndCheckLibrary(Builtin::kBuiltinLibrary);
   CHECK_RESULT(builtin_lib);
 
   // Prepare for script loading by setting up the 'print' and 'timer'
@@ skipping 442 matching lines @@
 
   return Process::GlobalExitCode();
 }
 
 }  // namespace bin
 }  // namespace dart
 
 int main(int argc, char** argv) {
   return dart::bin::main(argc, argv);
 }