From 02f3cea403bb52268992d865b602cd5bfc2f6159 Mon Sep 17 00:00:00 2001
From: Han <handong@bu.edu>
Date: Mon, 20 Nov 2017 16:30:52 -0500
Subject: [PATCH] feat(pthread): new pthread interface

Added experimental pthread_create and pthread_join interfaces
that run on top of SpawnRemote and waits on Future for
each thread to do the join.
---
 src/native/pthread.cc | 58 ++++++++++++++++++++++++++++
 src/native/pthread.h  | 88 +++++++++++++++++++++++++++++++++++++++++++
 src/native/sched.h    |  8 ++++
 3 files changed, 154 insertions(+)
 create mode 100644 src/native/pthread.cc
 create mode 100644 src/native/pthread.h
 create mode 100644 src/native/sched.h

diff --git a/src/native/pthread.cc b/src/native/pthread.cc
new file mode 100644
index 00000000..652175e5
--- /dev/null
+++ b/src/native/pthread.cc
@@ -0,0 +1,58 @@
+#include "pthread.h"
+
+#include <ebbrt/EventManager.h>
+#include <ebbrt/Future.h>
+#include <ebbrt/LocalIdMap.h>
+#include <ebbrt/SpinBarrier.h>
+#include <ebbrt/UniqueIOBuf.h>
+#include <ebbrt/native/Cpu.h>
+
+static std::vector<ebbrt::Future<uint32_t>> vecfut_;
+static std::unordered_map<uint32_t, ebbrt::Promise<uint32_t>> mmap_;
+static uint64_t tid_;
+
+ebbrt::SpinLock spinlock_;
+
+void pthread_attr_init(pthread_attr_t* attr) {
+  vecfut_.clear();
+  mmap_.clear();
+  tid_ = 0;
+}
+
+int pthread_create(pthread_t* th, pthread_attr_t* attr, void* (*func)(void*),
+                   void* arg) {
+
+  *th = reinterpret_cast<pthread_t>(tid_);
+  size_t tid = reinterpret_cast<size_t>(tid_);
+
+  ebbrt::Promise<uint32_t> promise;
+  bool inserted;
+  auto f = promise.GetFuture();
+  vecfut_.push_back(std::move(f));
+  std::tie(std::ignore, inserted) = mmap_.emplace(tid, std::move(promise));
+
+  ebbrt::event_manager->SpawnRemote(
+      [func, arg, tid]() {
+        func((void*)arg);
+
+        std::lock_guard<ebbrt::SpinLock> l(spinlock_);
+        {
+          auto it = mmap_.find(tid);
+          assert(it != mmap_.end());
+          it->second.SetValue(tid);
+          mmap_.erase(it);
+        }
+      },
+      tid);
+
+  tid_++;
+
+  return 0;
+}
+
+int pthread_join(pthread_t threadn, void** value_ptr) {
+  size_t tid = static_cast<size_t>(threadn);
+  vecfut_[tid].Block();
+
+  return 0;
+}
diff --git a/src/native/pthread.h b/src/native/pthread.h
new file mode 100644
index 00000000..d5bf9819
--- /dev/null
+++ b/src/native/pthread.h
@@ -0,0 +1,88 @@
+#ifndef BAREMETAL_SRC_INCLUDE_EBBRT_PTHREAD_H_
+#define BAREMETAL_SRC_INCLUDE_EBBRT_PTHREAD_H_
+
+#include "sched.h"
+#include <ebbrt/Debug.h>
+#include <ebbrt/EventManager.h>
+#include <ebbrt/SpinLock.h>
+
+extern "C" {
+typedef unsigned long pthread_t;
+typedef unsigned int pthread_key_t;
+typedef struct {
+  int is_initialized;
+  void* stackaddr;
+  int stacksize;
+  int contentionscope;
+  int inheritsched;
+  int schedpolicy;
+  sched_param schedparam;
+  int detachstate;
+} pthread_attr_t;
+
+typedef struct {
+} pthread_barrier_t;
+typedef struct {
+} pthread_barrierattr_t;
+typedef struct {
+} pthread_cond_t;
+typedef struct {
+} pthread_condattr_t;
+typedef struct {
+} pthread_mutexattr_t;
+typedef struct {
+} pthread_rwlock_t;
+typedef struct {
+} pthread_rwlockattr_t;
+typedef struct {
+} pthread_spinlock_t;
+
+typedef struct { ebbrt::SpinLock spinlock; } pthread_mutex_t;
+
+void pthread_attr_init(pthread_attr_t* attr);
+int pthread_cond_broadcast(pthread_cond_t* cond);
+int pthread_cond_signal(pthread_cond_t* cond);
+int pthread_cond_timedwait(pthread_cond_t* cond, pthread_mutex_t* mutex,
+                           const struct timespec* abstime);
+int pthread_cond_wait(pthread_cond_t* cond, pthread_mutex_t* mutex);
+int pthread_cond_destroy(pthread_cond_t* cond);
+int pthread_cond_init(pthread_cond_t* __restrict cond,
+                      const pthread_condattr_t* __restrict attr);
+
+pthread_t pthread_self();
+int pthread_create(pthread_t*, pthread_attr_t*, void* (*)(void*), void*);
+int pthread_join(pthread_t, void**);
+int pthread_detach(pthread_t thread);
+int pthread_equal(pthread_t t1, pthread_t t2);
+
+void* pthread_getspecific(pthread_key_t key);
+int pthread_setspecific(pthread_key_t key, const void* value);
+int pthread_key_create(pthread_key_t* key, void (*destructor)(void*));
+int pthread_mutexattr_destroy(pthread_mutexattr_t* attr);
+int pthread_mutexattr_init(pthread_mutexattr_t* attr);
+int pthread_mutexattr_gettype(const pthread_mutexattr_t* __restrict attr,
+                              int* __restrict type);
+int pthread_mutexattr_settype(pthread_mutexattr_t* attr, int type);
+
+typedef struct {
+} pthread_once_t;
+int pthread_once(pthread_once_t* once_control, void (*init_routine)(void));
+
+#define PTHREAD_MUTEX_INITIALIZER                                              \
+  { 0 }
+#define PTHREAD_COND_INITIALIZER                                               \
+  {}
+#define PTHREAD_ONCE_INIT                                                      \
+  {}
+
+#define PTHREAD_MUTEX_RECURSIVE 33
+
+int pthread_mutex_init(pthread_mutex_t* mutex, const pthread_mutexattr_t* attr);
+int pthread_mutex_lock(pthread_mutex_t* mutex);
+int pthread_mutex_trylock(pthread_mutex_t* mutex);
+int pthread_mutex_unlock(pthread_mutex_t* mutex);
+int pthread_mutex_destroy(pthread_mutex_t* mutex);
+
+}  // "C"
+
+#endif
diff --git a/src/native/sched.h b/src/native/sched.h
new file mode 100644
index 00000000..0e8f8965
--- /dev/null
+++ b/src/native/sched.h
@@ -0,0 +1,8 @@
+#ifndef BAREMETAL_SRC_INCLUDE_EBBRT_SCHED_H_
+#define BAREMETAL_SRC_INCLUDE_EBBRT_SCHED_H_
+
+typedef struct { int sched_priority; } sched_param;
+
+extern int sched_yield();
+
+#endif