Add string class that uses ExternalAsciiStringResource.

Change the natives to use this class instead of creating completely new
strings. Reduces memory usage by about 1 MB.

1 files changed, 42 insertions, 0 deletions

diff --git a/src/node_string.h b/src/node_string.h
new file mode 100644
index 0000000000..1854cc2933
--- /dev/null
+++ b/src/node_string.h
@@ -0,0 +1,42 @@
+#ifndef SRC_NODE_STRING_H_
+#define SRC_NODE_STRING_H_
+
+#include <v8.h>
+
+namespace node {
+
+#define IMMUTABLE_STRING(string_literal)                                \
+  ::node::ImmutableAsciiSource::CreateFromLiteral(                      \
+      string_literal "", sizeof(string_literal) - 1)
+#define BUILTIN_ASCII_ARRAY(array, len)                                 \
+  ::node::ImmutableAsciiSource::CreateFromLiteral(array, len)
+
+class ImmutableAsciiSource : public v8::String::ExternalAsciiStringResource {
+ public:
+  static v8::Handle<v8::String> CreateFromLiteral(const char *string_literal,
+                                                  size_t length);
+
+  ImmutableAsciiSource(const char *src, size_t src_len)
+      : buffer_(src),
+        buf_len_(src_len) {
+  }
+
+  ~ImmutableAsciiSource() {
+  }
+
+  const char *data() const {
+      return buffer_;
+  }
+
+  size_t length() const {
+      return buf_len_;
+  }
+
+ private:
+  const char *buffer_;
+  size_t buf_len_;
+};
+
+}  // namespace node
+
+#endif  // SRC_NODE_STRING_H_