Implement fromEnvironment on bool, int and String

runtime/lib/integers.cc

Index: runtime/lib/integers.cc
diff --git a/runtime/lib/integers.cc b/runtime/lib/integers.cc
index 8df13969a51561e12272fbe6d073b603be4c29e6..bce9d03ffb11a17de42d1e13ba304d8e504d9e26 100644
--- a/runtime/lib/integers.cc
+++ b/runtime/lib/integers.cc
@@ -4,9 +4,12 @@
 
 #include "vm/bootstrap_natives.h"
 
+#include "include/dart_api.h"
 #include "vm/bigint_operations.h"
 #include "vm/dart_entry.h"
+#include "vm/dart_api_impl.h"
 #include "vm/exceptions.h"
+#include "vm/isolate.h"
 #include "vm/native_entry.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
@@ -226,6 +229,46 @@ DEFINE_NATIVE_ENTRY(Integer_parse, 1) {
 }
 
 
+DEFINE_NATIVE_ENTRY(Integer_fromEnvironment, 3) {
+  GET_NON_NULL_NATIVE_ARGUMENT(String, name, arguments->NativeArgAt(1));
+  GET_NATIVE_ARGUMENT(Integer, default_value, arguments->NativeArgAt(2));
+  // Call the embedder to supply us with the environment.
+  Dart_ConfigCallback callback = isolate->config_callback();
+  if (callback != NULL) {
+    Dart_Handle result = callback(kIntegerConfig,
+                                  Api::NewHandle(isolate, name.raw()));
+    if (Dart_IsString(result)) {
+      int digits_len;
+      Dart_StringLength(result, &digits_len);
+      if (digits_len > 0) {
+        const char *digits;
+        Dart_StringToCString(result, &digits);
+        // TODO(sgjesse): Support hex strings.

[Ivan Posva, 2013/10/29 21:42:59]

Integer::NewCanonical already deals with hex strings.

[Søren Gjesse, 2013/10/30 11:44:02]

Changed checking to check for decimal or hexdecimal string before calling
Integer::NewCanonical.

+        bool is_number = true;
+        for (int i = 0; i < digits_len && is_number; i++) {
+          is_number = ('0' <= digits[i]) && digits[i] <= '9';
+        }
+        if (digits_len > 0 && is_number) {
+          const Object& value =
+              Object::Handle(isolate, Api::UnwrapHandle(result));
+          ASSERT(value.IsString());
+          return Integer::NewCanonical(String::Cast(value));
+        } else {
+          Exceptions::ThrowArgumentError(
+              String::Handle(
+                  String::New("Environment value is not an integer")));
+        }
+      }
+    }
+  }
+  if (default_value.IsNull()) {
+    Exceptions::ThrowArgumentError(
+        String::Handle(String::New("Environment value does not have a value")));
+  }
+  return default_value.raw();
+}
+
+
 // Passing true for 'silent' prevents throwing JavascriptIntegerOverflow.
 static RawInteger* ShiftOperationHelper(Token::Kind kind,
                                         const Integer& value,