uhd: Replace Boost mutexes and locks with standard options

This is a very mechanical task that could almost have been done with
sed. Boost versions of mutexes and locks were removed, and replaced with
std:: versions. The replacement tables are as follows:

== Mutexes ==
- boost::mutex -> std::mutex
- boost::recursive_mutex -> std::recursive_mutex

Mutexes behave identically between Boost and std:: and have the same
API.

== Locks ==
C++11 has only two types of lock that we use/need in UHD:
- std::lock_guard: Identical to boost::lock_guard
- std::unique_lock: Identical to boost::unique_lock

Boost also has boost::mutex::scoped_lock, which is a typedef for
boost::unique_lock<>. However, we often have used scoped_lock where we
meant to use lock_guard<>. The name is a bit misleading, "scoped lock"
sounding a bit like an RAII mechanism. Therefore, some previous
boost::mutex::scoped_lock are now std::lock_guard<>.

std::unique_lock is required when doing more than RAII locking (i.e.,
unlocking, relocking, usage with condition variables, etc.).

== Condition Variables ==
Condition variables were out of the scope of this lock/mutex change, but
in UHD, we inconsistently use boost::condition vs.
boost::condition_variable. The former is a templated version of the
latter, and thus works fine with std::mutex'es. Therefore, some
boost::condition_variable where changed to boost::condition.

All locks and mutexes use `#include <mutex>`. The corresponding Boost
includes were removed. In some cases, this exposed issues with implicit
Boost includes elsewhere. The missing explicit includes were added.

1 files changed, 4 insertions, 3 deletions

diff --git a/host/lib/utils/tasks.cpp b/host/lib/utils/tasks.cpp
index 0eddd2488..95219cb0c 100644
--- a/host/lib/utils/tasks.cpp
+++ b/host/lib/utils/tasks.cpp
@@ -16,6 +16,7 @@
 #include <exception>
 #include <functional>
 #include <iostream>
+#include <mutex>
 #include <thread>
 #include <vector>
 
@@ -106,7 +107,7 @@ public:
      */
     msg_payload_t get_msg_from_dump_queue(uint32_t sid) override
     {
-        boost::mutex::scoped_lock lock(_mutex);
+        std::lock_guard<std::mutex> lock(_mutex);
         msg_payload_t b;
         for (size_t i = 0; i < _dump_queue.size(); i++) {
             if (sid == _dump_queue[i].first) {
@@ -133,7 +134,7 @@ private:
                      * pushed to the dump_queue. This way ctrl_cores can check dump_queue
                      * for missing messages.
                      */
-                    boost::mutex::scoped_lock lock(_mutex);
+                    std::lock_guard<std::mutex> lock(_mutex);
                     _dump_queue.push_back(buff.get());
                 }
             }
@@ -155,7 +156,7 @@ private:
             << "The task loop will now exit, things may not work." << msg;
     }
 
-    boost::mutex _mutex;
+    std::mutex _mutex;
     boost::thread_group _thread_group;
     boost::barrier _spawn_barrier;
     bool _running;