1 files changed, 131 insertions, 0 deletions
diff --git a/ext/memory_buffer.c b/ext/memory_buffer.c
new file mode 100644
index 0000000..bd1bac8
--- /dev/null
+++ b/ext/memory_buffer.c
@@ -0,0 +1,131 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include <ruby.h>
+#include <constants.h>
+#include "macros.h"
+
+ID buf_ivar_id;
+ID index_ivar_id;
+
+ID slice_method_id;
+
+int GARBAGE_BUFFER_SIZE;
+
+#define GET_BUF(self) rb_ivar_get(self, buf_ivar_id)
+
+VALUE rb_thrift_memory_buffer_write(VALUE self, VALUE str);
+VALUE rb_thrift_memory_buffer_read(VALUE self, VALUE length_value);
+VALUE rb_thrift_memory_buffer_read_byte(VALUE self);
+VALUE rb_thrift_memory_buffer_read_into_buffer(VALUE self, VALUE buffer_value, VALUE size_value);
+
+VALUE rb_thrift_memory_buffer_write(VALUE self, VALUE str) {
+  VALUE buf = GET_BUF(self);
+  rb_str_buf_cat(buf, RSTRING_PTR(str), RSTRING_LEN(str));
+  return Qnil;
+}
+
+VALUE rb_thrift_memory_buffer_read(VALUE self, VALUE length_value) {
+  int length = FIX2INT(length_value);
+  
+  VALUE index_value = rb_ivar_get(self, index_ivar_id);
+  int index = FIX2INT(index_value);
+  
+  VALUE buf = GET_BUF(self);
+  VALUE data = rb_funcall(buf, slice_method_id, 2, index_value, length_value);
+  
+  index += length;
+  if (index > RSTRING_LEN(buf)) {
+    index = RSTRING_LEN(buf);
+  }
+  if (index >= GARBAGE_BUFFER_SIZE) {
+    rb_ivar_set(self, buf_ivar_id, rb_funcall(buf, slice_method_id, 2, INT2FIX(index), INT2FIX(RSTRING_LEN(buf) - 1)));
+    index = 0;
+  }
+  rb_ivar_set(self, index_ivar_id, INT2FIX(index));
+
+  if (RSTRING_LEN(data) < length) {
+    rb_raise(rb_eEOFError, "Not enough bytes remain in memory buffer");
+  }
+
+  return data;
+}
+
+VALUE rb_thrift_memory_buffer_read_byte(VALUE self) {
+  VALUE index_value = rb_ivar_get(self, index_ivar_id);
+  int index = FIX2INT(index_value);
+
+  VALUE buf = GET_BUF(self);
+  if (index >= RSTRING_LEN(buf)) {
+    rb_raise(rb_eEOFError, "Not enough bytes remain in memory buffer");
+  }
+  char byte = RSTRING_PTR(buf)[index++];
+
+  if (index >= GARBAGE_BUFFER_SIZE) {
+    rb_ivar_set(self, buf_ivar_id, rb_funcall(buf, slice_method_id, 2, INT2FIX(index), INT2FIX(RSTRING_LEN(buf) - 1)));
+    index = 0;
+  }
+  rb_ivar_set(self, index_ivar_id, INT2FIX(index));
+
+  int result = (int) byte;
+  return INT2FIX(result);
+}
+
+VALUE rb_thrift_memory_buffer_read_into_buffer(VALUE self, VALUE buffer_value, VALUE size_value) {
+  int i = 0;
+  int size = FIX2INT(size_value);
+  int index;
+  VALUE buf = GET_BUF(self);
+
+  while (i < size) {
+    index = FIX2INT(rb_ivar_get(self, index_ivar_id));
+    if (index >= RSTRING_LEN(buf)) {
+      rb_raise(rb_eEOFError, "Not enough bytes remain in memory buffer");
+    }
+    char byte = RSTRING_PTR(buf)[index++];
+
+    if (index >= GARBAGE_BUFFER_SIZE) {
+      rb_ivar_set(self, buf_ivar_id, rb_funcall(buf, slice_method_id, 2, INT2FIX(index), INT2FIX(RSTRING_LEN(buf) - 1)));
+      index = 0;
+    }
+    rb_ivar_set(self, index_ivar_id, INT2FIX(index));
+
+    if (i >= RSTRING_LEN(buffer_value)) {
+      rb_raise(rb_eIndexError, "index %d out of string", i);
+    }
+    ((char*)RSTRING_PTR(buffer_value))[i] = byte;
+    i++;
+  }
+  return INT2FIX(i);
+}
+
+void Init_memory_buffer() {
+  VALUE thrift_memory_buffer_class = rb_const_get(thrift_module, rb_intern("MemoryBufferTransport"));
+  rb_define_method(thrift_memory_buffer_class, "write", rb_thrift_memory_buffer_write, 1);
+  rb_define_method(thrift_memory_buffer_class, "read", rb_thrift_memory_buffer_read, 1);
+  rb_define_method(thrift_memory_buffer_class, "read_byte", rb_thrift_memory_buffer_read_byte, 0);
+  rb_define_method(thrift_memory_buffer_class, "read_into_buffer", rb_thrift_memory_buffer_read_into_buffer, 2);
+  
+  buf_ivar_id = rb_intern("@buf");
+  index_ivar_id = rb_intern("@index");
+  
+  slice_method_id = rb_intern("slice");
+  
+  GARBAGE_BUFFER_SIZE = FIX2INT(rb_const_get(thrift_memory_buffer_class, rb_intern("GARBAGE_BUFFER_SIZE")));
+}