Remove boost from core popsift library

.gitignore

@@ -45,3 +45,5 @@ oxford
 # Temporary files
 .DS_Store
 
+# Downloaded archives for tests.
+*.tgz

CMakeLists.txt

@@ -10,13 +10,9 @@ OPTION(PopSift_USE_POSITION_INDEPENDENT_CODE "Generate position independent code
 OPTION(PopSift_USE_GRID_FILTER "Switch off grid filtering to massively reduce compile time while debugging other things." ON)
 OPTION(PopSift_USE_NORMF "The __normf function computes Euclidian distance on large arrays. Fast but stability is uncertain." OFF)
 OPTION(PopSift_USE_TEST_CMD "Add testing step for functional verification" OFF)
-OPTION(PopSift_BOOST_USE_STATIC_LIBS "Link with static Boost libraries" OFF)
+OPTION(PopSift_BOOST_USE_STATIC_LIBS "Link examples with static Boost libraries" OFF)
 OPTION(PopSift_NVCC_WARNINGS "Switch on several additional warning for CUDA nvcc" OFF)
 
-if(PopSift_BOOST_USE_STATIC_LIBS)
-  set(Boost_USE_STATIC_LIBS ON)
-endif()
-
 if(PopSift_USE_POSITION_INDEPENDENT_CODE)
   set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 endif()
@@ -40,13 +36,6 @@ set(CMAKE_CXX_STANDARD_REQUIRED ON)
 # set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -G")
 # set(CMAKE_C_FLAGS_DEBUG   "${CMAKE_C_FLAGS_DEBUG}   -G")
 
-find_package(Boost 1.53.0 REQUIRED COMPONENTS system thread)
-if(WIN32)
-  add_definitions("-DBOOST_ALL_NO_LIB")
-  link_directories(Boost_LIBRARRY_DIR_DEBUG)
-  link_directories(Boost_LIBRARRY_DIR_RELEASE)
-endif(WIN32)
-
 if(BUILD_SHARED_LIBS)
   message(STATUS "BUILD_SHARED_LIBS ON")
   # Need to declare CUDA_USE_STATIC_CUDA_RUNTIME as an option to ensure that it is not overwritten in FindCUDA.

README.md

@@ -10,16 +10,16 @@ Dependencies
 
 Most of the dependencies can be installed from the common repositories (apt, yum etc):
 
-Boost >= 1.55 ([atomic, chrono, date-time, system, thread]-dev)
+Boost >= 1.55 ([atomic, chrono, date-time, system, thread]-dev) (only required for the application)
 CUDA >= 7.0
 DevIL (libdevil-dev) (only required for the application)
 
 Build
 -----
 
-PopSift has been developed and tested on Linux machines, mostly a variant of Ubuntu, but compiles on MacOSX as well. It comes as a CMake project and requires at least CUDA 7.0 and Boost >= 1.55. It is known to compile and work with NVidia cards of compute capability 3.0 (including the GT 650M), but the code is developed with the compute capability 5.2 card GTX 980 Ti in mind.
+PopSift has been developed and tested on Linux machines, mostly a variant of Ubuntu, but compiles on MacOSX as well. It comes as a CMake project and requires at least CUDA 7.0. The example application carries an additional dependency on Boost >= 1.55. It is known to compile and work with NVidia cards of compute capability 3.0 (including the GT 650M), but the code is developed with the compute capability 5.2 card GTX 980 Ti in mind.
 
-If you want to avoid building the application you can run cmake with the option `-DPopSift_BUILD_EXAMPLES:BOOL=OFF`.
+If you want to avoid building the example application you can run cmake with the option `-DPopSift_BUILD_EXAMPLES:BOOL=OFF`.
 If you want to build PopSift as a shared library: `-DBUILD_SHARED_LIBS=ON`.
 
 In order to build the library you can run:

src/CMakeLists.txt

@@ -1,6 +1,6 @@
 set(LIBRARY_OUTPUT_PATH ${PROJECT_BINARY_DIR})
 
-CUDA_INCLUDE_DIRECTORIES(${Boost_INCLUDE_DIRS} ${CMAKE_CURRENT_BINARY_DIR}/popsift)
+CUDA_INCLUDE_DIRECTORIES(${CMAKE_CURRENT_BINARY_DIR}/popsift)
 
 CUDA_ADD_LIBRARY(popsift
 	popsift/popsift.cpp popsift/popsift.h
@@ -49,7 +49,7 @@ configure_file(popsift/sift_config.h.in
 # BUILD_INTERFACE allows to include the directory with source only when target is
 # built in the building tree (ie, not from an install location)
 target_include_directories(popsift 
-            PUBLIC ${Boost_INCLUDE_DIRS} ${CUDA_INCLUDE_DIRS}
+            PUBLIC ${CUDA_INCLUDE_DIRS}
             "$<BUILD_INTERFACE:${CMAKE_CURRENT_LIST_DIR}>")
 
 
@@ -58,7 +58,11 @@ set_target_properties(popsift PROPERTIES DEBUG_POSTFIX "d")
 
 # cannot use PRIVATE here as there is a bug in FindCUDA and CUDA_ADD_LIBRARY
 # https://gitlab.kitware.com/cmake/cmake/issues/16097
-target_link_libraries(popsift ${Boost_LIBRARIES} ${CUDA_CUDADEVRT_LIBRARY} ${CUDA_CUBLAS_LIBRARIES})
+target_link_libraries(popsift ${CUDA_CUDADEVRT_LIBRARY} ${CUDA_CUBLAS_LIBRARIES})
+
+# Link to threads because we're using C++11 std::thread.
+find_package(Threads REQUIRED)
+target_link_libraries(popsift ${CMAKE_THREAD_LIBS_INIT})
 
 
 # EXPORTING THE LIBRARY

src/application/CMakeLists.txt

@@ -14,9 +14,15 @@ endif()
 
 find_package(DevIL COMPONENTS IL ILU) # yields IL_FOUND, IL_LIBRARIES, IL_INCLUDE_DIR
 
-set(Boost_INCLUDE_DIRS "")
-set(Boost_LIBRARIES "")
-find_package(Boost 1.53.0 REQUIRED COMPONENTS filesystem program_options)
+if(PopSift_BOOST_USE_STATIC_LIBS)
+  set(Boost_USE_STATIC_LIBS ON)
+endif()
+find_package(Boost 1.53.0 REQUIRED COMPONENTS filesystem program_options system)
+if(WIN32)
+  add_definitions("-DBOOST_ALL_NO_LIB")
+  link_directories(Boost_LIBRARRY_DIR_DEBUG)
+  link_directories(Boost_LIBRARRY_DIR_RELEASE)
+endif(WIN32)
 
 set(PD_INCLUDE_DIRS    ${Boost_INCLUDE_DIRS})
 set(PD_LINK_LIBS       ${Boost_LIBRARIES} ${CUDA_CUDADEVRT_LIBRARY})

src/popsift/common/sync_queue.h

@@ -0,0 +1,49 @@
+#pragma once
+
+#include <condition_variable>
+#include <mutex>
+#include <queue>
+
+namespace popsift {
+
+/*************************************************************
+ * SyncQueue
+ * This is a basic alternative to the Boost sync_queue class.
+ * It lets threads push and pull items off a queue in a thread
+ * safe manner.
+ *************************************************************/
+template<typename T>
+class SyncQueue {
+ public:
+  SyncQueue() = default;
+
+  /* Push an item onto the queue and signal it's available. */
+  void push(const T& value) {
+    std::unique_lock<std::mutex> lock(mtx_);
+    items_.push(value);
+    lock.unlock();
+    signal_.notify_one();
+  }
+
+  /* Check if the queue is empty - thread safety via mutex. */
+  bool empty() {
+    std::unique_lock<std::mutex> lock(mtx_);
+    return items_.empty();
+  }
+
+  /* BLOCKING. Pull an item off the queue, or, wait until one arrives. */
+  T pull() {
+    std::unique_lock<std::mutex> lock(mtx_);
+    signal_.wait(lock, [this] { return !items_.empty(); });
+    auto ans = items_.front();
+    items_.pop();
+    return ans;
+  }
+
+ private:
+  std::mutex mtx_;
+  std::queue<T> items_;
+  std::condition_variable signal_;
+};
+
+}  // namespace popsift

src/popsift/popsift.cpp

@@ -5,6 +5,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
+#include <cmath>
+#include <cstring>
 #include <fstream>
 
 #include "popsift.h"
@@ -29,11 +31,11 @@ PopSift::PopSift( const popsift::Config& config, popsift::Config::ProcessingMode
 
     configure( config, true );
 
-    _pipe._thread_stage1.reset( new boost::thread( &PopSift::uploadImages, this ));
+    _pipe._thread_stage1.reset( new std::thread( &PopSift::uploadImages, this ));
     if( mode == popsift::Config::ExtractingMode )
-        _pipe._thread_stage2.reset( new boost::thread( &PopSift::extractDownloadLoop, this ));
+        _pipe._thread_stage2.reset( new std::thread( &PopSift::extractDownloadLoop, this ));
     else
-        _pipe._thread_stage2.reset( new boost::thread( &PopSift::matchPrepareLoop, this ));
+        _pipe._thread_stage2.reset( new std::thread( &PopSift::matchPrepareLoop, this ));
 }
 
 PopSift::PopSift( ImageMode imode )
@@ -50,8 +52,8 @@ PopSift::PopSift( ImageMode imode )
         _pipe._unused.push( new popsift::ImageFloat );
     }
 
-    _pipe._thread_stage1.reset( new boost::thread( &PopSift::uploadImages, this ));
-    _pipe._thread_stage2.reset( new boost::thread( &PopSift::extractDownloadLoop, this ));
+    _pipe._thread_stage1.reset( new std::thread( &PopSift::uploadImages, this ));
+    _pipe._thread_stage2.reset( new std::thread( &PopSift::extractDownloadLoop, this ));
 }
 
 PopSift::~PopSift()

src/popsift/popsift.h

@@ -12,9 +12,9 @@
 #include <stack>
 #include <queue>
 #include <future>
-#include <boost/thread/thread.hpp>
-#include <boost/thread/sync_queue.hpp>
+#include <thread>
 
+#include "common/sync_queue.h"
 #include "sift_conf.h"
 #include "sift_extremum.h"
 
@@ -74,11 +74,11 @@ class PopSift
 {
     struct Pipe
     {
-        std::unique_ptr<boost::thread>         _thread_stage1;
-        std::unique_ptr<boost::thread>         _thread_stage2;
-        boost::sync_queue<SiftJob*>            _queue_stage1;
-        boost::sync_queue<SiftJob*>            _queue_stage2;
-        boost::sync_queue<popsift::ImageBase*> _unused;
+        std::unique_ptr<std::thread>            _thread_stage1;
+        std::unique_ptr<std::thread>            _thread_stage2;
+        popsift::SyncQueue<SiftJob*>            _queue_stage1;
+        popsift::SyncQueue<SiftJob*>            _queue_stage2;
+        popsift::SyncQueue<popsift::ImageBase*> _unused;
 
         popsift::Pyramid*                      _pyramid{nullptr};