Hi there,

I trying to use Xenomai functions in a C++ file in a ROS(1) package.

The hardware plataform used is a Raspberry Pi 3

The goal is to create a Xenomai task with ROS functions inside.

As a entry point, I download the example from Xenomai website.

The makefile for a simple task program, outside catkin workspace, is:

SKIN=alchemy
MAIN_SRC=ex01
TARGET=ex01

LM=-lm

CFLAGS := $(shell xeno-config --skin=alchemy --cflags)
LDFLAGS := $(LM) $(shell xeno-config --skin=alchemy --ldflags)
CC := $(shell xeno-config --cc)

$(TARGET): $(MAIN_SRC).c
    $(CC) -o $@ $< $(CFLAGS) $(LDFLAGS)

The xeno-config --skin=alchemy --cflags returns arm-linux-gnueabihf-gcc.

In the catkin workspace I create a simple package named beginner_tutorials based in the example from:

http://wiki.ros.org/ROS/Tutorials/WritingPublisherSubscriber%28c%2B%2B%29.

The program files are located in "src" subdirectory from package: talker.cpp and listener.cpp. In this sources was added the Xenomai include files to use its functions.

In "CMakeLists.txt" located in "beginner_tutorials", was added this commands to make possible compile and link the Xenomai lib to my executable:

execute_process(COMMAND xeno-config --skin=alchemy --cflags OUTPUT_VARIABLE XENO_CFLAGS)
execute_process(COMMAND xeno-config --skin=alchemy --ldflags OUTPUT_VARIABLE XENO_LDFLAGS)

SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${XENO_CFLAGS}")
SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${XENO_LDFLAGS}")

add_executable(talker src/talker.cpp)
target_link_libraries(talker ${catkin_LIBRARIES})

add_executable(listener src/listener.cpp)
target_link_libraries(listener ${catkin_LIBRARIES})

message(STATUS "C COMPILER") # too see compiler and used and flags
message(STATUS ${CMAKE_CXX_COMPILER})
message(STATUS "XENOMAI CFLAGS")
message(STATUS ${XENO_CFLAGS})
message(STATUS "XENOMAI LDFLAGS")
message(STATUS ${XENO_LDFLAGS})

When I go to "~/catkinws" and tip `catkinmake`, the results are as folow:

Base path: /root/catkin_ws
Source space: /root/catkin_ws/src
Build space: /root/catkin_ws/build
Devel space: /root/catkin_ws/devel
Install space: /root/catkin_ws/install
####
#### Running command: "make cmake_check_build_system" in "/root/catkin_ws/build"
####
-- Using CATKIN_DEVEL_PREFIX: /root/catkin_ws/devel
-- Using CMAKE_PREFIX_PATH: /opt/ros/kinetic
-- This workspace overlays: /opt/ros/kinetic
-- Using PYTHON_EXECUTABLE: /usr/bin/python
-- Using Debian Python package layout
-- Using empy: /usr/bin/empy
-- Using CATKIN_ENABLE_TESTING: ON
-- Call enable_testing()
-- Using CATKIN_TEST_RESULTS_DIR: /root/catkin_ws/build/test_results
-- Found gmock sources under '/usr/src/gmock': gmock will be built
-- Found gtest sources under '/usr/src/gmock': gtests will be built
-- Using Python nosetests: /usr/bin/nosetests-2.7
-- catkin 0.7.11
-- BUILD_SHARED_LIBS is on
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- ~~  traversing 1 packages in topological order:
-- ~~  - beginner_tutorials
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- +++ processing catkin package: 'beginner_tutorials'
-- ==> add_subdirectory(beginner_tutorials)
-- C COMPILER
-- /usr/bin/c++

-- XENOMAI CFLAGS
-- -I/usr/xenomai/include/cobalt -I/usr/xenomai/include -march=armv7-a -mfloat-abi=hard -mfpu=neon -ffast-math -D_GNU_SOURCE -D_REENTRANT -D__COBALT__ -I/usr/xenomai/include/alchemy

-- XENOMAI LDFLAGS
-- -Wl,--no-as-needed -Wl,@/usr/xenomai/lib/modechk.wrappers -lalchemy -lcopperplate /usr/xenomai/lib/xenomai/bootstrap.o -Wl,--wrap=main -Wl,--dynamic-list=/usr/xenomai/lib/dynlist.ld -L/usr/xenomai/lib -lcobalt -lmodechk -lpthread -lrt  

-- Configuring done
-- Generating done
-- Build files have been written to: /root/catkin_ws/build
####
#### Running command: "make -j4 -l4" in "/root/catkin_ws/build"
####
[ 50%] Linking CXX executable /root/catkin_ws/devel/lib/beginner_tutorials/listener
[ 50%] Linking CXX executable /root/catkin_ws/devel/lib/beginner_tutorials/talker
c++: fatal error: no input files
compilation terminated.
c++: fatal error: no input files
compilation terminated.
beginner_tutorials/CMakeFiles/listener.dir/build.make:115: recipe for target '/root/catkin_ws/devel/lib/beginner_tutorials/listener' failed
make[2]: *** [/root/catkin_ws/devel/lib/beginner_tutorials/listener] Error 4
CMakeFiles/Makefile2:946: recipe for target 'beginner_tutorials/CMakeFiles/listener.dir/all' failed
make[1]: *** [beginner_tutorials/CMakeFiles/listener.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
beginner_tutorials/CMakeFiles/talker.dir/build.make:115: recipe for target '/root/catkin_ws/devel/lib/beginner_tutorials/talker' failed
make[2]: *** [/root/catkin_ws/devel/lib/beginner_tutorials/talker] Error 4
CMakeFiles/Makefile2:909: recipe for target 'beginner_tutorials/CMakeFiles/talker.dir/all' failed
make[1]: *** [beginner_tutorials/CMakeFiles/talker.dir/all] Error 2
Makefile:138: recipe for target 'all' failed
make: *** [all] Error 2
Invoking "make -j4 -l4" failed

From what I could understand, the catkin did not find the Xenomai files needed for linking. That's right? Another thing is that catkin uses g++ for compile, but this is a problem?

What I can do to solve this?

Thanks.

EDIT 1:

I can do compile with the following commands in the package's CMakeLists.txt:

execute_process(COMMAND xeno-config --skin=alchemy --cflags OUTPUT_VARIABLE XENO_CFLAGS)
execute_process(COMMAND xeno-config --skin=alchemy --ldflags OUTPUT_VARIABLE XENO_LDFLAGS)

SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${XENO_CFLAGS}")
string(STRIP ${CMAKE_CXX_FLAGS} CMAKE_CXX_FLAGS)

SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--wrap=main -Wl,--no-as-needed -Wl,@/usr/xenomai/lib/modechk.wrappers -lalchemy -lcopperplate /usr/xenomai/lib/xenomai/bootstrap.o -Wl,--dynamic-list=/usr/xenomai/lib/dynlist.ld -L/usr/xenomai/lib -lcobalt -lmodechk -lpthread -lrt")

add_executable(talker src/talker.cpp )
target_link_libraries(talker ${catkin_LIBRARIES} )

This time, I compile just talker for simplicity.

The output from catkin_make was:

Base path: /root/catkin_ws
Source space: /root/catkin_ws/src
Build space: /root/catkin_ws/build
Devel space: /root/catkin_ws/devel
Install space: /root/catkin_ws/install
####
#### Running command: "make cmake_check_build_system" in "/root/catkin_ws/build"
####
-- Using CATKIN_DEVEL_PREFIX: /root/catkin_ws/devel
-- Using CMAKE_PREFIX_PATH: /root/catkin_ws/devel;/opt/ros/kinetic
-- This workspace overlays: /root/catkin_ws/devel;/opt/ros/kinetic
-- Using PYTHON_EXECUTABLE: /usr/bin/python
-- Using Debian Python package layout
-- Using empy: /usr/bin/empy
-- Using CATKIN_ENABLE_TESTING: ON
-- Call enable_testing()
-- Using CATKIN_TEST_RESULTS_DIR: /root/catkin_ws/build/test_results
-- Found gmock sources under '/usr/src/gmock': gmock will be built
-- Found gtest sources under '/usr/src/gmock': gtests will be built
-- Using Python nosetests: /usr/bin/nosetests-2.7
-- catkin 0.7.11
-- BUILD_SHARED_LIBS is on
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- ~~  traversing 1 packages in topological order:
-- ~~  - beginner_tutorials
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- +++ processing catkin package: 'beginner_tutorials'
-- ==> add_subdirectory(beginner_tutorials)

-- Configuring done
-- Generating done
-- Build files have been written to: /root/catkin_ws/build
####
#### Running command: "make -j4 -l4" in "/root/catkin_ws/build"
####
[ 50%] Building CXX object beginner_tutorials/CMakeFiles/talker.dir/src/talker.cpp.o
[100%] Linking CXX executable /root/catkin_ws/devel/lib/beginner_tutorials/talker
/usr/bin/ld: warning: libboost_system.so.1.54.0, needed by /usr/lib/gcc/arm-linux-gnueabihf/4.9/../../../arm-linux-gnueabihf/libconsole_bridge.so, may conflict with libboost_system.so.1.55.0
/usr/bin/ld: warning: libboost_thread.so.1.54.0, needed by /usr/lib/gcc/arm-linux-gnueabihf/4.9/../../../arm-linux-gnueabihf/libconsole_bridge.so, may conflict with libboost_thread.so.1.55.0
[100%] Built target talker 

In main function I try initialize ros::init and inside the created task in talker the anothers ros functions for publish are used:

#include "ros/ros.h"
#include "std_msgs/String.h"

#include <sstream>

#include <stdio.h>
#include <signal.h>
#include <unistd.h>
#include <sys/mman.h>

#include <alchemy/task.h>
#include <alchemy/timer.h>

#include  <trank/rtdk.h>

RT_TASK demo_task;

void demo(void *arg)
{
  RT_TASK *curtask;
  RT_TASK_INFO curtaskinfo;

  // inquire current task
  curtask=rt_task_self();
  rt_task_inquire(curtask,&curtaskinfo);
  // print task name
  rt_printf("Task name : %s \n", curtaskinfo.name);

  rt_printf("PASS_0\n");

  ros::NodeHandle n;

  rt_printf("PASS_1\n");

  ros::Publisher chatter_pub = n.advertise<std_msgs::String>("chatter", 1000);

  ros::Rate loop_rate(10);

  int count = 0;
  while (ros::ok())
  {
    std_msgs::String msg;

    std::stringstream ss;
    ss << "hello world " << count;
    msg.data = ss.str();


    rt_printf("PASS_%d\n", count);
    ROS_INFO("%s", msg.data.c_str());


    chatter_pub.publish(msg);

    ros::spinOnce();

    loop_rate.sleep();
    ++count;
  }
}


int main(int argc, char **argv)
{

 char  str[10] ;

 struct args main_args;

  ros::init(argc, argv, "talker");

 // Perform auto-init of rt_print buffers if the task doesn't do so
  rt_print_auto_init(1);

  // Lock memory : avoid memory swapping for this program
  mlockall(MCL_CURRENT|MCL_FUTURE);

  rt_printf("start task\n");

  /*
   * Arguments: &task,
   *            name,
   *            stack size (0=default),
   *            priority,
   *            mode (FPU, start suspended, ...)
   */
  sprintf(str,"hello");
  rt_task_create(&demo_task, str, 100000000, 50, 0);

  /*
   * Arguments: &task,
   *            task function,
   *            function argument
   */
  rt_task_start(&demo_task, &demo, 0);

}

However, on execution, this error are throw:

rosrun beginner_tutorials talker
start task
Task name : hello 
PASS_0
terminate called after throwing an instance of 'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::lock_error> >'
  what():  boost: mutex lock failed in pthread_mutex_lock: Invalid argument
Aborted

From the code, can be seen that this exception are thrown when "NodeHandle n" is created. The question now is: why this exception are thrown?

EDIT 2:

I change the system for one with just one libboost version (1.58). As can be seen, the binary use just one version of libboost.

ldd talker 
    linux-vdso.so.1 =>  (0x7ef8b000)
    /usr/lib/arm-linux-gnueabihf/libarmmem.so (0x76f66000)
    libalchemy.so.0 => /usr/xenomai/lib/libalchemy.so.0 (0x76f06000)
    libcopperplate.so.0 => /usr/xenomai/lib/libcopperplate.so.0 (0x76eec000)
    libcobalt.so.2 => /usr/xenomai/lib/libcobalt.so.2 (0x76ec3000)
    libmodechk.so.0 => /usr/xenomai/lib/libmodechk.so.0 (0x76eb1000)
    libpthread.so.0 => /lib/arm-linux-gnueabihf/libpthread.so.0 (0x76e8d000)
    librt.so.1 => /lib/arm-linux-gnueabihf/librt.so.1 (0x76e77000)
    libroscpp.so => /opt/ros/kinetic/lib/libroscpp.so (0x76d48000)
    libboost_filesystem.so.1.58.0 => /usr/lib/arm-linux-gnueabihf/libboost_filesystem.so.1.58.0 (0x76d27000)
    libboost_signals.so.1.58.0 => /usr/lib/arm-linux-gnueabihf/libboost_signals.so.1.58.0 (0x76d05000)
    librosconsole.so => /opt/ros/kinetic/lib/librosconsole.so (0x76cd1000)
    librosconsole_log4cxx.so => /opt/ros/kinetic/lib/librosconsole_log4cxx.so (0x76caf000)
    librosconsole_backend_interface.so => /opt/ros/kinetic/lib/librosconsole_backend_interface.so (0x76c9d000)
    liblog4cxx.so.10 => /usr/lib/arm-linux-gnueabihf/liblog4cxx.so.10 (0x76b57000)
    libboost_regex.so.1.58.0 => /usr/lib/arm-linux-gnueabihf/libboost_regex.so.1.58.0 (0x76aa0000)
    libxmlrpcpp.so => /opt/ros/kinetic/lib/libxmlrpcpp.so (0x76a7c000)
    libroscpp_serialization.so => /opt/ros/kinetic/lib/libroscpp_serialization.so (0x76a69000)
    librostime.so => /opt/ros/kinetic/lib/librostime.so (0x76a3a000)
    libcpp_common.so => /opt/ros/kinetic/lib/libcpp_common.so (0x76a24000)
    libboost_system.so.1.58.0 => /usr/lib/arm-linux-gnueabihf/libboost_system.so.1.58.0 (0x76a11000)
    libboost_thread.so.1.58.0 => /usr/lib/arm-linux-gnueabihf/libboost_thread.so.1.58.0 (0x769e6000)
    libboost_chrono.so.1.58.0 => /usr/lib/arm-linux-gnueabihf/libboost_chrono.so.1.58.0 (0x769d0000)
    libboost_date_time.so.1.58.0 => /usr/lib/arm-linux-gnueabihf/libboost_date_time.so.1.58.0 (0x769b3000)
    libboost_atomic.so.1.58.0 => /usr/lib/arm-linux-gnueabihf/libboost_atomic.so.1.58.0 (0x769a1000)
    libconsole_bridge.so.0.2 => /usr/lib/arm-linux-gnueabihf/libconsole_bridge.so.0.2 (0x7698d000)
    libstdc++.so.6 => /usr/lib/arm-linux-gnueabihf/libstdc++.so.6 (0x7687f000)
    libm.so.6 => /lib/arm-linux-gnueabihf/libm.so.6 (0x76807000)
    libgcc_s.so.1 => /lib/arm-linux-gnueabihf/libgcc_s.so.1 (0x767df000)
    libc.so.6 => /lib/arm-linux-gnueabihf/libc.so.6 (0x766f3000)
    /lib/ld-linux-armhf.so.3 (0x76f7b000)
    libapr-1.so.0 => /usr/lib/arm-linux-gnueabihf/libapr-1.so.0 (0x766c6000)
    libaprutil-1.so.0 => /usr/lib/arm-linux-gnueabihf/libaprutil-1.so.0 (0x7669d000)
    libicui18n.so.55 => /usr/lib/arm-linux-gnueabihf/libicui18n.so.55 (0x76504000)
    libicuuc.so.55 => /usr/lib/arm-linux-gnueabihf/libicuuc.so.55 (0x763e7000)
    libuuid.so.1 => /lib/arm-linux-gnueabihf/libuuid.so.1 (0x763d3000)
    libdl.so.2 => /lib/arm-linux-gnueabihf/libdl.so.2 (0x763c0000)
    libcrypt.so.1 => /lib/arm-linux-gnueabihf/libcrypt.so.1 (0x76381000)
    libexpat.so.1 => /lib/arm-linux-gnueabihf/libexpat.so.1 (0x76359000)
    libicudata.so.55 => /usr/lib/arm-linux-gnueabihf/libicudata.so.55 (0x74a92000)

However, the same error appears on execution:

'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::lock_error> >'
      what():  boost: mutex lock failed in pthread_mutex_lock: Invalid argument
    Aborted