diff --git a/aos/logging/context.cc b/aos/logging/context.cc
new file mode 100644
index 0000000..3701b00
--- /dev/null
+++ b/aos/logging/context.cc
@@ -0,0 +1,98 @@
+#include "aos/logging/context.h"
+
+#include <string.h>
+#include <sys/prctl.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <string>
+
+#include "aos/die.h"
+#include "aos/linux_code/complex_thread_local.h"
+
+namespace aos {
+namespace logging {
+namespace internal {
+namespace {
+
+// TODO(brians): Differentiate between threads with the same name in the same
+// process.
+
+::std::string GetMyName() {
+  // The maximum number of characters that can make up a thread name.
+  // The docs are unclear if it can be 16 characters with no '\0', so we'll be
+  // safe by adding our own where necessary.
+  static const size_t kThreadNameLength = 16;
+
+  ::std::string process_name(program_invocation_short_name);
+
+  char thread_name_array[kThreadNameLength + 1];
+  if (prctl(PR_GET_NAME, thread_name_array) != 0) {
+    PDie("prctl(PR_GET_NAME, %p) failed", thread_name_array);
+  }
+  thread_name_array[sizeof(thread_name_array) - 1] = '\0';
+  ::std::string thread_name(thread_name_array);
+
+  // If the first bunch of characters are the same.
+  // We cut off comparing at the shorter of the 2 strings because one or the
+  // other often ends up cut off.
+  if (strncmp(thread_name.c_str(), process_name.c_str(),
+              ::std::min(thread_name.length(), process_name.length())) == 0) {
+    // This thread doesn't have an actual name.
+    return process_name;
+  }
+
+  return process_name + '.' + thread_name;
+}
+
+::aos::ComplexThreadLocal<Context> my_context;
+
+// True if we're going to delete the current Context object ASAP. The
+// reason for doing this instead of just deleting them is that tsan (at least)
+// doesn't like it when pthread_atfork handlers do complicated stuff and it's
+// not a great idea anyways.
+thread_local bool delete_current_context(false);
+
+}  // namespace
+
+::std::atomic<LogImplementation *> global_top_implementation(NULL);
+
+Context::Context()
+    : implementation(global_top_implementation.load()),
+      sequence(0) {
+  cork_data.Reset();
+}
+
+// Used in aos/linux_code/init.cc when a thread's name is changed.
+void ReloadThreadName() {
+  if (my_context.created()) {
+    ::std::string my_name = GetMyName();
+    if (my_name.size() + 1 > sizeof(Context::name)) {
+      Die("logging: process/thread name '%s' is too long\n",
+          my_name.c_str());
+    }
+    strcpy(my_context->name, my_name.c_str());
+    my_context->name_size = my_name.size();
+  }
+}
+
+Context *Context::Get() {
+  if (__builtin_expect(delete_current_context, false)) {
+    my_context.Clear();
+    delete_current_context = false;
+  }
+  if (__builtin_expect(!my_context.created(), false)) {
+    my_context.Create();
+    ReloadThreadName();
+    my_context->source = getpid();
+  }
+  return my_context.get();
+}
+
+void Context::Delete() {
+  delete_current_context = true;
+}
+
+}  // namespace internal
+}  // namespace logging
+}  // namespace aos