Thread local storage for grpc
diff --git a/include/grpc/support/tls.h b/include/grpc/support/tls.h
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+/*
+ *
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef GRPC_SUPPORT_TLS_H
+#define GRPC_SUPPORT_TLS_H
+
+#include "port_platform.h"
+
+/* Thread local storage.
+
+ A minimal wrapper that should be implementable across many compilers,
+ and implementable efficiently across most modern compilers.
+
+ Thread locals have type gpr_intptr.
+
+ Declaring a thread local variable 'foo':
+ GPR_TLS_DECL(foo, initial_value);
+ Thread locals always have static scope.
+
+ Initializing a thread local (must be done at library initialization
+ time):
+ gpr_tls_init(&foo);
+
+ Destroying a thread local:
+ gpr_tls_destroy(&foo);
+
+ Setting a thread local:
+ gpr_tls_set(&foo, new_value);
+
+ Accessing a thread local:
+ current_value = gpr_tls_get(&foo, value);
+
+ ALL functions here may be implemented as macros. */
+
+#ifdef GPR_GCC_TLS
+#include "tls_gcc.h"
+#endif
+
+#ifdef GPR_MSVC_TLS
+#include "tls_msvc.h"
+#endif
+
+#ifdef GPR_PTHREAD_TLS
+#include "tls_pthread.h"
+#endif
+
+#endif