Linux/MacOSX port of DriverLoader

CMakeLists.txt

@@ -102,7 +102,7 @@ target_link_libraries(ViveLoaderLib
     PUBLIC
     OpenVRDriver osvr::osvrUtil linkable_into_dll
     PRIVATE
-    filesystem_lib JsonCpp::JsonCpp)
+    filesystem_lib JsonCpp::JsonCpp ${CMAKE_DL_LIBS}) # ${CMAKE_DL_LIBS} is set to empty string, when system doesn't provide dlfcn. For example, Windows.
 target_include_directories(ViveLoaderLib PUBLIC ${CMAKE_CURRENT_BINARY_DIRECTORY} PRIVATE ${Boost_INCLUDE_DIRS})
 
 # Build the plugin

ChaperoneData.cpp

@@ -37,6 +37,7 @@
 #include <iostream>
 #include <map>
 #include <sstream>
+#include <algorithm>
 
 #ifdef _WIN32
 #define WIN32_LEAN_AND_MEAN
@@ -100,6 +101,7 @@ getFile(std::string const &fn,
     return os.str();
 }
 #else
+#include <cstring> // strerror
 
 std::string
 getFile(std::string const &fn,
@@ -119,7 +121,7 @@ getFile(std::string const &fn,
     }
     std::ostringstream os;
     std::string temp;
-    while (std::getline(os, temp)) {
+    while (std::getline(s, temp)) {
         os << temp;
     }
     return os.str();

DisplayDescriptor.cpp

@@ -26,6 +26,7 @@
 
 // Internal Includes
 #include "DisplayDescriptor.h"
+#include "osvr/Util/PlatformConfig.h"
 
 // Library/third-party includes
 #include <json/reader.h>
@@ -37,6 +38,10 @@
 #include <cmath>
 #include <iostream>
 
+#if defined(OSVR_LINUX) || defined(OSVR_MACOSX)
+#include <float.h> // FLT_EPSILON
+#endif
+
 namespace osvr {
 namespace vive {
 

DriverLoader.cpp

@@ -37,6 +37,8 @@
 #define WIN32_LEAN_AND_MEAN
 #define NO_MINMAX
 #include <windows.h>
+#elif defined(OSVR_LINUX) || defined(OSVR_MACOSX)
+#include <dlfcn.h>
 #endif
 
 namespace osvr {
@@ -48,10 +50,8 @@ namespace vive {
 /// Platform-specific handle to dynamic library
 #if defined(OSVR_WINDOWS)
         HMODULE driver_ = nullptr;
-#elif defined(OSVR_MACOSX)
-#error "Implementation incomplete!"
-#elif defined(OSVR_LINUX)
-#error "Implementation incomplete!"
+#elif defined(OSVR_MACOSX) || defined(OSVR_LINUX)
+        void *driver_ = nullptr;
 #endif
 
         /// Destructor: should contain platform-specific code to unload dynamic
@@ -61,10 +61,10 @@ namespace vive {
             if (driver_) {
                 FreeLibrary(driver_);
             }
-#elif defined(OSVR_MACOSX)
-#error "Implementation incomplete! Unload dynamic library here!"
-#elif defined(OSVR_LINUX)
-#error "Implementation incomplete! Unload dynamic library here!"
+#elif defined(OSVR_MACOSX) || defined(OSVR_LINUX)
+            if (driver_) {
+                dlclose(driver_);
+            }
 #endif
         }
     };
@@ -91,12 +91,19 @@ namespace vive {
             throw CouldNotLoadEntryPoint();
         }
         factory_ = reinterpret_cast<DriverFactory>(proc);
-#elif defined(OSVR_MACOSX)
-#error                                                                         \
-    "Implementation incomplete! Load dynamic library here and retrieve entry point function here!"
-#elif defined(OSVR_LINUX)
-#error                                                                         \
-    "Implementation incomplete! Load dynamic library here and retrieve entry point function here!"
+#elif defined(OSVR_LINUX) || defined(OSVR_MACOSX)
+        impl_->driver_ = dlopen(driverFile.c_str(), RTLD_NOW | RTLD_GLOBAL);
+        if (!impl_->driver_) {
+            reset();
+            throw CouldNotLoadDriverModule(dlerror());
+        }
+
+        auto proc = dlsym(impl_->driver_, ENTRY_POINT_FUNCTION_NAME);
+        if (!proc) {
+            reset();
+            throw CouldNotLoadEntryPoint(dlerror());
+        }
+        factory_ = reinterpret_cast<DriverFactory>(proc);                                                                       \
 #endif
     }
 

DriverLoader.h

@@ -26,7 +26,8 @@
 #define INCLUDED_DriverLoader_h_GUID_882F2FD5_F218_42BE_3088_31CF712EC455
 
 // Internal Includes
-// - none
+#include <osvr/Util/PlatformConfig.h>
+#include <InterfaceTraits.h>
 
 // Library/third-party includes
 // - none
@@ -40,14 +41,26 @@
 namespace osvr {
 namespace vive {
     struct CouldNotLoadDriverModule : std::runtime_error {
-        CouldNotLoadDriverModule()
+        CouldNotLoadDriverModule(const char *errString = nullptr)
+#if defined(OSVR_LINUX) || defined(OSVR_MACOSX)
+            : std::runtime_error(
+                  "Could not load driver module: " +
+                   std::string(errString)) {}
+#else
             : std::runtime_error("Could not load driver module.") {}
+#endif
     };
 
     struct CouldNotLoadEntryPoint : std::runtime_error {
-        CouldNotLoadEntryPoint()
+        CouldNotLoadEntryPoint(const char *errString = nullptr)
+#if defined(OSVR_LINUX) || defined(OSVR_MACOSX)
+            : std::runtime_error(
+                  "Could not load entry point function from driver: " +
+                   std::string(errString)) {}
+#else
             : std::runtime_error(
                   "Could not load entry point function from driver.") {}
+#endif
     };
 
     struct CouldNotGetInterface : std::runtime_error {

FindDriver.cpp

@@ -47,6 +47,7 @@
 #include <shlobj.h>
 #else
 #include <cstdlib> // for getenv
+#include <fstream> // std::ifstream
 #endif
 
 #undef VIVELOADER_VERBOSE

SearchPathExtender.h

@@ -101,7 +101,7 @@ namespace vive {
 #ifdef _MSC_VER
             _putenv_s(SEARCH_PATH_ENV, val.c_str());
 #else // not microsoft runtime specific
-            auto newValue = SEARCH_PATH_ENV + "=" + val;
+            auto newValue = SEARCH_PATH_ENV + std::string("=") + val;
             // Have to allocate new string because it becomes part of the
             // environment.
             char *newString = static_cast<char *>(malloc(newValue.size() + 1));