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.

3 files changed, 15 insertions, 16 deletions

diff --git a/host/lib/usrp/usrp2/io_impl.cpp b/host/lib/usrp/usrp2/io_impl.cpp
index 792b4721b..a966f91ea 100644
--- a/host/lib/usrp/usrp2/io_impl.cpp
+++ b/host/lib/usrp/usrp2/io_impl.cpp
@@ -92,7 +92,7 @@ public:
      */
     UHD_INLINE bool check_fc_condition(double timeout)
     {
-        boost::mutex::scoped_lock lock(_fc_mutex);
+        std::unique_lock<std::mutex> lock(_fc_mutex);
         if (this->ready())
             return true;
         boost::this_thread::disable_interruption di; // disable because the wait can throw
@@ -105,7 +105,7 @@ public:
      */
     UHD_INLINE void update_fc_condition(seq_type seq)
     {
-        boost::mutex::scoped_lock lock(_fc_mutex);
+        std::unique_lock<std::mutex> lock(_fc_mutex);
         _last_seq_ack = seq;
         lock.unlock();
         _fc_cond.notify_one();
@@ -117,7 +117,7 @@ private:
         return seq_type(_last_seq_out - _last_seq_ack) < _max_seqs_out;
     }
 
-    boost::mutex _fc_mutex;
+    std::mutex _fc_mutex;
     boost::condition _fc_cond;
     seq_type _last_seq_out, _last_seq_ack;
     const seq_type _max_seqs_out;
diff --git a/host/lib/usrp/usrp2/usrp2_fifo_ctrl.cpp b/host/lib/usrp/usrp2/usrp2_fifo_ctrl.cpp
index 116051216..a4f46fca6 100644
--- a/host/lib/usrp/usrp2/usrp2_fifo_ctrl.cpp
+++ b/host/lib/usrp/usrp2/usrp2_fifo_ctrl.cpp
@@ -12,9 +12,7 @@
 #include <uhd/utils/log.hpp>
 #include <uhd/utils/safe_call.hpp>
 #include <boost/asio.hpp> //htonl
-#include <boost/format.hpp>
-#include <boost/thread/mutex.hpp>
-#include <boost/thread/thread.hpp>
+#include <mutex>
 
 using namespace uhd;
 using namespace uhd::transport;
@@ -58,7 +56,7 @@ public:
      ******************************************************************/
     void poke32(const wb_addr_type addr, const uint32_t data) override
     {
-        boost::mutex::scoped_lock lock(_mutex);
+        std::lock_guard<std::mutex> lock(_mutex);
 
         this->send_pkt((addr - SETTING_REGS_BASE) / 4, data, POKE32_CMD);
 
@@ -67,7 +65,7 @@ public:
 
     uint32_t peek32(const wb_addr_type addr) override
     {
-        boost::mutex::scoped_lock lock(_mutex);
+        std::lock_guard<std::mutex> lock(_mutex);
 
         this->send_pkt((addr - READBACK_BASE) / 4, 0, PEEK32_CMD);
 
@@ -92,7 +90,7 @@ public:
      ******************************************************************/
     void init_spi(void)
     {
-        boost::mutex::scoped_lock lock(_mutex);
+        std::lock_guard<std::mutex> lock(_mutex);
 
         this->send_pkt(SPI_DIV, SPI_DIVIDER, POKE32_CMD);
         this->wait_for_ack(_seq_out - MAX_SEQS_OUT);
@@ -106,7 +104,7 @@ public:
         size_t num_bits,
         bool readback) override
     {
-        boost::mutex::scoped_lock lock(_mutex);
+        std::lock_guard<std::mutex> lock(_mutex);
 
         // load control word
         uint32_t ctrl_word = 0;
@@ -145,7 +143,7 @@ public:
      ******************************************************************/
     void set_time(const uhd::time_spec_t& time) override
     {
-        boost::mutex::scoped_lock lock(_mutex);
+        std::lock_guard<std::mutex> lock(_mutex);
         _time     = time;
         _use_time = _time != uhd::time_spec_t(0.0);
         if (_use_time)
@@ -154,13 +152,13 @@ public:
 
     uhd::time_spec_t get_time() override
     {
-        boost::mutex::scoped_lock lock(_mutex);
+        std::lock_guard<std::mutex> lock(_mutex);
         return _time;
     }
 
     void set_tick_rate(const double rate) override
     {
-        boost::mutex::scoped_lock lock(_mutex);
+        std::lock_guard<std::mutex> lock(_mutex);
         _tick_rate = rate;
     }
 
@@ -234,7 +232,7 @@ private:
     }
 
     zero_copy_if::sptr _xport;
-    boost::mutex _mutex;
+    std::mutex _mutex;
     uint16_t _seq_out;
     uint16_t _seq_ack;
     uhd::time_spec_t _time;
diff --git a/host/lib/usrp/usrp2/usrp2_iface.cpp b/host/lib/usrp/usrp2/usrp2_iface.cpp
index 23104d18f..c79ffccab 100644
--- a/host/lib/usrp/usrp2/usrp2_iface.cpp
+++ b/host/lib/usrp/usrp2/usrp2_iface.cpp
@@ -26,6 +26,7 @@
 #include <chrono>
 #include <functional>
 #include <iostream>
+#include <mutex>
 #include <thread>
 
 using namespace uhd;
@@ -268,7 +269,7 @@ public:
         uint32_t lo = USRP2_FW_COMPAT_NUM,
         uint32_t hi = USRP2_FW_COMPAT_NUM)
     {
-        boost::mutex::scoped_lock lock(_ctrl_mutex);
+        std::lock_guard<std::mutex> lock(_ctrl_mutex);
 
         for (size_t i = 0; i < CTRL_RECV_RETRIES; i++) {
             try {
@@ -472,7 +473,7 @@ private:
     udp_simple::sptr _ctrl_transport;
 
     // used in send/recv
-    boost::mutex _ctrl_mutex;
+    std::mutex _ctrl_mutex;
     uint32_t _ctrl_seq_num;
     uint32_t _protocol_compat;