refactor rcl into a functional library

rcl/CMakeLists.txt

@@ -3,14 +3,68 @@ cmake_minimum_required(VERSION 2.8.3)
 project(rcl)
 
 find_package(ament_cmake REQUIRED)
+find_package(rcl_interfaces REQUIRED)
+find_package(rmw REQUIRED)
+find_package(rmw_implementation REQUIRED)
+find_package(rmw_implementation_cmake REQUIRED)
+find_package(rosidl_generator_c REQUIRED)
 
+include_directories(include)
+
+if(NOT WIN32)
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra")
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra")
+endif()
+
+set(${PROJECT_NAME}_sources
+  src/rcl/allocator.c
+  src/rcl/common.c
+  src/rcl/guard_condition.c
+  src/rcl/node.c
+  src/rcl/publisher.c
+  src/rcl/rcl.c
+  src/rcl/subscription.c
+  src/rcl/wait.c
+  src/rcl/time.c
+  src/rcl/timer.c
+)
+
+macro(target)
+  add_library(${PROJECT_NAME}${target_suffix} SHARED ${${PROJECT_NAME}_sources})
+  ament_target_dependencies(${PROJECT_NAME}${target_suffix}
+    "rcl_interfaces"
+    "rmw"
+    "rosidl_generator_c"
+    "${rmw_implementation}"
+  )
+
+  # Causes the visibility macros to use dllexport rather than dllimport,
+  # which is appropriate when building the dll but not consuming it.
+  target_compile_definitions(${PROJECT_NAME}${target_suffix} PRIVATE "RCL_BUILDING_DLL")
+
+  install(
+    TARGETS ${PROJECT_NAME}${target_suffix}
+    ARCHIVE DESTINATION lib
+    LIBRARY DESTINATION lib
+    RUNTIME DESTINATION bin)
+endmacro()
+
+call_for_each_rmw_implementation(target GENERATE_DEFAULT)
+
+ament_export_dependencies(rcl_interfaces)
 ament_export_dependencies(rmw)
+ament_export_dependencies(rmw_implementation)
+ament_export_dependencies(rosidl_generator_c)
 
 ament_export_include_directories(include)
 
+ament_export_libraries(${PROJECT_NAME})
+
 if(AMENT_ENABLE_TESTING)
   find_package(ament_lint_auto REQUIRED)
   ament_lint_auto_find_test_dependencies()
+
+  add_subdirectory(test)
 endif()
 
 ament_package()

rcl/include/rcl/allocator.h

@@ -0,0 +1,82 @@
+// Copyright 2015 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCL__ALLOCATOR_H_
+#define RCL__ALLOCATOR_H_
+
+#if __cplusplus
+extern "C"
+{
+#endif
+
+#include "rcl/macros.h"
+#include "rcl/types.h"
+#include "rcl/visibility_control.h"
+
+/// Encapsulation of an allocator.
+/* To use malloc, free, and realloc use rcl_get_default_allocator().
+ *
+ * The allocator should be trivially copyable.
+ * Meaning that the struct should continue to work after being assignment
+ * copied into a new struct.
+ * Specifically the object pointed to by the state pointer should remain valid
+ * until all uses of the allocator have been made.
+ * Particular care should be taken when giving an allocator to rcl_init_* where
+ * it is stored within another object and used later.
+ */
+typedef struct rcl_allocator_t
+{
+  /// Allocate memory, given a size and state structure.
+  /* An error should be indicated by returning NULL. */
+  void * (*allocate)(size_t size, void * state);
+  /// Deallocate previously allocated memory, mimicking free().
+  void (* deallocate)(void * pointer, void * state);
+  /// Reallocate if possible, otherwise it deallocates and allocates.
+  /* If unsupported then do deallocate and then allocate.
+   * This should behave as realloc is described, as opposed to reallocf, i.e.
+   * the memory given by pointer will not be free'd automatically if realloc
+   * fails.
+   * For reallocf behavior use rcl_reallocf().
+   * This function must be able to take an input pointer of NULL and succeed.
+   */
+  void * (*reallocate)(void * pointer, size_t size, void * state);
+  /// Implementation defined state storage.
+  /* This is passed as the second parameter to other allocator functions. */
+  void * state;
+} rcl_allocator_t;
+
+/// Return a properly initialized rcl_allocator_t with default values.
+/* This function does not allocate heap memory.
+ * This function is thread-safe.
+ * This function is lock-free.
+ */
+RCL_PUBLIC
+RCL_WARN_UNUSED
+rcl_allocator_t
+rcl_get_default_allocator();
+
+/// Emulate the behavior of reallocf.
+/* This function will return NULL if the allocator is NULL or has NULL for
+ * function pointer fields.
+ */
+RCL_PUBLIC
+RCL_WARN_UNUSED
+void *
+rcl_reallocf(void * pointer, size_t size, rcl_allocator_t * allocator);
+
+#if __cplusplus
+}
+#endif
+
+#endif  // RCL__ALLOCATOR_H_

rcl/include/rcl/error_handling.h

@@ -0,0 +1,38 @@
+// Copyright 2015 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCL__ERROR_HANDLING_H_
+#define RCL__ERROR_HANDLING_H_
+
+#include "rmw/error_handling.h"
+
+/* The error handling in RCL is just an alias to the error handling in RMW. */
+
+typedef rmw_error_state_t rcl_error_state_t;
+
+#define rcl_set_error_state rmw_set_error_state
+
+#define RCL_SET_ERROR_MSG(msg) RMW_SET_ERROR_MSG(msg)
+
+#define rcl_error_is_set rmw_error_is_set
+
+#define rcl_get_error_state rmw_get_error_state
+
+#define rcl_get_error_string rmw_get_error_string
+
+#define rcl_get_error_string_safe rmw_get_error_string_safe
+
+#define rcl_reset_error rmw_reset_error
+
+#endif  // RCL__ERROR_HANDLING_H_

rcl/include/rcl/guard_condition.h

@@ -0,0 +1,174 @@
+// Copyright 2015 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCL__GUARD_CONDITION_H_
+#define RCL__GUARD_CONDITION_H_
+
+#if __cplusplus
+extern "C"
+{
+#endif
+
+#include "rcl/macros.h"
+#include "rcl/node.h"
+#include "rcl/visibility_control.h"
+
+/// Internal rcl guard condition implementation struct.
+struct rcl_guard_condition_impl_t;
+
+/// Handle for a rcl guard condition.
+typedef struct rcl_guard_condition_t
+{
+  struct rcl_guard_condition_impl_t * impl;
+} rcl_guard_condition_t;
+
+/// Options available for a rcl guard condition.
+typedef struct rcl_guard_condition_options_t
+{
+  /// Custom allocator for the guard condition, used for internal allocations.
+  rcl_allocator_t allocator;
+} rcl_guard_condition_options_t;
+
+/// Return a rcl_guard_condition_t struct with members set to NULL.
+RCL_PUBLIC
+RCL_WARN_UNUSED
+rcl_guard_condition_t
+rcl_get_zero_initialized_guard_condition();
+
+/// Initialize a rcl guard_condition.
+/* After calling this function on a rcl_guard_condition_t, it can be passed to
+ * rcl_wait() and then concurrently it can be triggered to wake-up rcl_wait().
+ *
+ * The given rcl_node_t must be valid and the resulting rcl_guard_condition_t
+ * is only valid as long as the given rcl_node_t remains valid.
+ *
+ * Expected usage:
+ *
+ *    #include <rcl/rcl.h>
+ *
+ *    rcl_node_t node = rcl_get_zero_initialized_node();
+ *    rcl_node_options_t node_ops = rcl_node_get_default_options();
+ *    rcl_ret_t ret = rcl_node_init(&node, "node_name", &node_ops);
+ *    // ... error handling
+ *    rcl_guard_condition_t guard_condition = rcl_get_zero_initialized_guard_condition();
+ *    ret = rcl_guard_condition_init(
+ *      &guard_condition, &node, rcl_guard_condition_get_default_options());
+ *    // ... error handling, and on shutdown do deinitialization:
+ *    ret = rcl_guard_condition_fini(&guard_condition, &node);
+ *    // ... error handling for rcl_guard_condition_fini()
+ *    ret = rcl_node_fini(&node);
+ *    // ... error handling for rcl_deinitialize_node()
+ *
+ * This function does allocate heap memory.
+ * This function is not thread-safe.
+ * This function is lock-free.
+ *
+ * \TODO(wjwwood): does this function need a node to be passed to it? (same for fini)
+ *
+ * \param[inout] guard_condition preallocated guard_condition structure
+ * \param[in] node valid rcl node handle
+ * \param[in] options the guard_condition's options
+ * \return RCL_RET_OK if guard_condition was initialized successfully, or
+ *         RCL_RET_ALREADY_INIT if the guard condition is already initialized, or
+ *         RCL_RET_INVALID_ARGUMENT if any arugments are invalid, or
+ *         RCL_RET_BAD_ALLOC if allocating memory failed, or
+ *         RCL_RET_ERROR if an unspecified error occurs.
+ */
+RCL_PUBLIC
+RCL_WARN_UNUSED
+rcl_ret_t
+rcl_guard_condition_init(
+  rcl_guard_condition_t * guard_condition,
+  const rcl_node_t * node,
+  const rcl_guard_condition_options_t options);
+
+/// Finalize a rcl_guard_condition_t.
+/* After calling, calls to rcl_guard_condition_trigger() will fail when using
+ * this guard condition.
+ * However, the given node handle is still valid.
+ *
+ * This function does free heap memory and can allocate memory on errors.
+ * This function is not thread-safe with rcl_guard_condition_trigger().
+ * This function is lock-free.
+ *
+ * \param[inout] guard_condition handle to the guard_condition to be finalized
+ * \param[in] node handle to the node used to create the guard_condition
+ * \return RCL_RET_OK if guard_condition was finalized successfully, or
+ *         RCL_RET_INVALID_ARGUMENT if any arugments are invalid, or
+ *         RCL_RET_ERROR if an unspecified error occurs.
+ */
+RCL_PUBLIC
+RCL_WARN_UNUSED
+rcl_ret_t
+rcl_guard_condition_fini(rcl_guard_condition_t * guard_condition, rcl_node_t * node);
+
+/// Return the default options in a rcl_guard_condition_options_t struct.
+/* This function does not allocate heap memory.
+ * This function is thread-safe.
+ * This function is lock-free.
+ */
+RCL_PUBLIC
+RCL_WARN_UNUSED
+rcl_guard_condition_options_t
+rcl_guard_condition_get_default_options();
+
+/// Trigger a rcl guard condition.
+/* This function can fail, and therefore return NULL, if the:
+ *   - guard condition is NULL
+ *   - guard condition is invalid (never called init or called fini)
+ *
+ * A guard condition can be triggered from any thread.
+ *
+ * This function does not allocate heap memory, but can on errors.
+ * This function is thread-safe with itself, but cannot be called concurrently
+ * with rcl_guard_condition_fini() on the same guard condition.
+ * This function is lock-free, but the underlying system calls may not be.
+ *
+ * \param[in] guard_condition handle to the guard_condition to be triggered
+ * \return RCL_RET_OK if the guard condition was triggered, or
+ *         RCL_RET_INVALID_ARGUMENT if any arugments are invalid, or
+ *         RCL_RET_ERROR if an unspecified error occurs.
+ */
+RCL_PUBLIC
+RCL_WARN_UNUSED
+rcl_ret_t
+rcl_guard_condition_trigger(const rcl_guard_condition_t * guard_condition);
+
+/// Return the rmw guard condition handle.
+/* The handle returned is a pointer to the internally held rmw handle.
+ * This function can fail, and therefore return NULL, if the:
+ *   - guard_condition is NULL
+ *   - guard_condition is invalid (never called init, called fini, or invalid node)
+ *
+ * The returned handle is made invalid if the guard condition is finalized or
+ * if rcl_shutdown() is called.
+ * The returned handle is not guaranteed to be valid for the life time of the
+ * guard condition as it may be finalized and recreated itself.
+ * Therefore it is recommended to get the handle from the guard condition using
+ * this function each time it is needed and avoid use of the handle
+ * concurrently with functions that might change it.
+ *
+ * \param[in] guard_condition pointer to the rcl guard_condition
+ * \return rmw guard_condition handle if successful, otherwise NULL
+ */
+RCL_PUBLIC
+RCL_WARN_UNUSED
+rmw_guard_condition_t *
+rcl_guard_condition_get_rmw_handle(const rcl_guard_condition_t * guard_condition);
+
+#if __cplusplus
+}
+#endif
+
+#endif  // RCL__GUARD_CONDITION_H_

rcl/include/rcl/macros.h

@@ -0,0 +1,33 @@
+// Copyright 2015 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCL__MACROS_H_
+#define RCL__MACROS_H_
+
+#if __cplusplus
+extern "C"
+{
+#endif
+
+#ifndef _WIN32
+# define RCL_WARN_UNUSED __attribute__((warn_unused_result))
+#else
+# define RCL_WARN_UNUSED _Check_return_
+#endif
+
+#if __cplusplus
+}
+#endif
+
+#endif  // RCL__MACROS_H_