Initial support for Windows / MSVC (#165)

CMakeLists.txt

@@ -48,7 +48,14 @@ find_package(Sanitizers)
 # Code
 install(DIRECTORY include/datadog DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
 file(GLOB DD_OPENTRACING_SOURCES "src/*.cpp")
-add_compile_options(-Wall -Wextra -Werror -Wnon-virtual-dtor -Woverloaded-virtual -Wold-style-cast -std=c++14)
+message(STATUS "Compiler ID: ${CMAKE_CXX_COMPILER_ID}")
+if((CMAKE_CXX_COMPILER_ID MATCHES "GNU") OR (CMAKE_CXX_COMPILER_ID MATCHES "Clang"))
+  add_compile_options(-Wall -Wextra -Werror -Wnon-virtual-dtor -Woverloaded-virtual -Wold-style-cast -std=c++14)
+elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
+  add_compile_options(/W3)
+else()
+  message(FATAL_ERROR "Unknown compiler ${CMAKE_CXX_COMPILER_ID}")
+endif()
 
 # Outputs
 set(DATADOG_LINK_LIBRARIES ${OPENTRACING_LIB} ${CURL_LIBRARIES} ${ZLIB_LIBRARIES} Threads::Threads)
@@ -59,7 +66,7 @@ if(BUILD_SHARED)
   add_sanitizers(dd_opentracing)
   target_link_libraries(dd_opentracing ${DATADOG_LINK_LIBRARIES})
   set_target_properties(dd_opentracing PROPERTIES SOVERSION ${SOVERSION})
-
+  target_compile_definitions(dd_opentracing PRIVATE DD_OPENTRACING_SHARED)
   install(TARGETS dd_opentracing
           LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
           ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})
@@ -70,6 +77,7 @@ if(BUILD_STATIC)
   add_library(dd_opentracing-static STATIC ${DD_OPENTRACING_SOURCES})
   add_sanitizers(dd_opentracing-static)
   set_target_properties(dd_opentracing-static PROPERTIES OUTPUT_NAME dd_opentracing POSITION_INDEPENDENT_CODE ON)
+  target_compile_definitions(dd_opentracing PRIVATE DD_OPENTRACING_STATIC)
   install(TARGETS dd_opentracing-static
           LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
           ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})

README.md

@@ -17,7 +17,7 @@ For some quick-start examples, see the [examples](examples/) folder.
 
 Before considering contributions to the project, please take a moment to read our brief [contribution guidelines](CONTRIBUTING.md).
 
-## Build and Test
+## Build and Test (Linux and macOS)
 
 ### Dependencies
 
@@ -62,6 +62,39 @@ Additional libraries are installed via a script.
 
 If you want [sanitizers](https://github.com/google/sanitizers) to be enabled, then add either the `-DSANITIZE_THREAD=ON -DSANITIZE_UNDEFINED=ON` or `-DSANITIZE_ADDRESS=ON` flags to cmake, running the tests will now also check with the sanitizers.
 
+### Build (Windows)
+
+**NOTE**: This is currently Early Access, and issues should be reported only via GitHub Issues. Installation steps are likely to change based on user feedback and becoming available via Vcpkg.
+
+### Dependencies
+
+Building this project requires the following tools installed:
+
+- Visual Studio 2019 with "Desktop development for C++" installed
+- Vcpkg
+- Git
+
+### Build Steps
+
+The commands below should be executed in an `x64 Native Tools Command Prompt` shell.
+
+- Clone the repository
+    ```sh
+    cd %HOMEPATH%
+    git clone https://github.com/DataDog/dd-opentracing-cpp
+    ```
+- Generate build files using `cmake`
+    ```bat
+    cd dd-opentracing-cpp
+    mkdir .build
+    cd .build
+    cmake -DCMAKE_TOOLCHAIN_FILE=%HOMEPATH%\vcpkg\scripts\buildsystems\vcpkg.cmake ..
+    ```
+- Run the build
+    ```bat
+    cmake --build . -- -p:Configuration=RelWithDebInfo
+    ```
+
 ### Integration tests
 
 Integration tests require additional tools installed:

examples/cpp-tracing/compiled-in/tracer_example.cpp

@@ -1,14 +1,16 @@
 #include <datadog/opentracing.h>
+#include <datadog/tags.h>
 #include <iostream>
 #include <string>
 
 int main(int argc, char* argv[]) {
-  datadog::opentracing::TracerOptions tracer_options{"dd-agent", 8126, "compiled-in example"};
+  datadog::opentracing::TracerOptions tracer_options{"localhost", 8126, "compiled-in example"};
   auto tracer = datadog::opentracing::makeTracer(tracer_options);
 
   // Create some spans.
   {
     auto span_a = tracer->StartSpan("A");
+    span_a->SetTag(datadog::tags::environment, "production");
     span_a->SetTag("tag", 123);
     auto span_b = tracer->StartSpan("B", {opentracing::ChildOf(&span_a->context())});
     span_b->SetTag("tag", "value");

include/datadog/opentracing.h

@@ -1,6 +1,21 @@
 #ifndef DD_INCLUDE_OPENTRACING_TRACER_H
 #define DD_INCLUDE_OPENTRACING_TRACER_H
 
+#ifdef _MSC_VER
+#ifndef DD_OPENTRACING_STATIC
+// dllexport/dllimport declspecs need to be applied when building a DLL
+#ifdef DD_OPENTRACING_SHARED
+#define DD_OPENTRACING_API __declspec(dllexport)
+#else  // DD_OPENTRACING_SHARED
+#define DD_OPENTRACING_API __declspec(dllimport)
+#endif  // DD_OPENTRACING_SHARED
+#else   // DD_OPENTRACING_STATIC
+#define DD_OPENTRACING_API
+#endif  // DD_OPENTRACING_STATIC
+#else   // _MSC_VER
+#define DD_OPENTRACING_API
+#endif  // _MSC_VER
+
 #include <opentracing/tracer.h>
 
 #include <cmath>
@@ -140,7 +155,7 @@ class TraceEncoder {
 
 // makeTracer returns an opentracing::Tracer that submits traces to the Datadog Agent.
 // This should be used when control over the HTTP requests to the Datadog Agent is not required.
-std::shared_ptr<ot::Tracer> makeTracer(const TracerOptions& options);
+DD_OPENTRACING_API std::shared_ptr<ot::Tracer> makeTracer(const TracerOptions& options);
 // makeTracerAndEncoder initializes an opentracing::Tracer and provides an encoder
 // to use when submitting traces to the Datadog Agent.
 // This should be used in applications that need to also control the HTTP requests to the Datadog

src/sample.h

@@ -1,6 +1,12 @@
 #ifndef DD_OPENTRACING_SAMPLE_H
 #define DD_OPENTRACING_SAMPLE_H
 
+#ifdef _MSC_VER
+// When compiling with MSVC, std::numeric_limits::max is confused the the max macro,
+// and causes compilation errors.
+#undef max
+#endif
+
 #include <datadog/opentracing.h>
 #include <opentracing/tracer.h>
 #include <iostream>

src/tracer.cpp

@@ -2,9 +2,15 @@
 #include <datadog/tags.h>
 #include <errno.h>
 #include <opentracing/ext/tags.h>
-#include <pthread.h>
 #include <sys/stat.h>
+
+#ifdef _MSC_VER
+#include <winsock.h>
+#else
+#include <pthread.h>
 #include <unistd.h>
+#endif
+
 #include <fstream>
 #include <random>
 
@@ -24,7 +30,14 @@ namespace opentracing {
 namespace {
 class TlsRandomNumberGenerator {
  public:
-  TlsRandomNumberGenerator() { pthread_atfork(nullptr, nullptr, onFork); }
+  TlsRandomNumberGenerator() {
+#ifdef _MSC_VER
+// When compiling with MSVC, pthreads are not used.
+// TODO: investigate equivalent of pthread_atfork for MSVC
+#else
+    pthread_atfork(nullptr, nullptr, onFork);
+#endif
+  }
 
   static std::mt19937_64 &generator() { return random_number_generator_; }
 

src/transport.cpp

@@ -63,6 +63,10 @@ CURLcode CurlHandle::setopt(CURLoption key, long value) {
   return curl_easy_setopt(handle_, key, value);
 }
 
+CURLcode CurlHandle::setopt(CURLoption key, size_t value) {
+  return curl_easy_setopt(handle_, key, value);
+}
+
 void CurlHandle::setHeaders(std::map<std::string, std::string> headers) {
   for (auto& header : headers) {
     headers_[header.first] = header.second;  // Overwrite.

src/transport.h

@@ -16,6 +16,7 @@ class Handle {
   virtual ~Handle() {}
   virtual CURLcode setopt(CURLoption key, const char* value) = 0;
   virtual CURLcode setopt(CURLoption key, long value) = 0;
+  virtual CURLcode setopt(CURLoption key, size_t value) = 0;
   virtual void setHeaders(std::map<std::string, std::string> headers) = 0;
   virtual CURLcode perform() = 0;
   virtual std::string getError() = 0;
@@ -30,6 +31,7 @@ class CurlHandle : public Handle {
   ~CurlHandle() override;
   CURLcode setopt(CURLoption key, const char* value) override;
   CURLcode setopt(CURLoption key, long value) override;
+  CURLcode setopt(CURLoption key, size_t value) override;
   void setHeaders(std::map<std::string, std::string> headers) override;
   CURLcode perform() override;
   std::string getError() override;

test/mocks.h

@@ -229,6 +229,14 @@ struct MockHandle : public Handle {
     return rcode;
   }
 
+  CURLcode setopt(CURLoption key, size_t value) override {
+    std::unique_lock<std::mutex> lock(mutex);
+    if (rcode == CURLE_OK) {
+      options[key] = std::to_string(value);
+    }
+    return rcode;
+  }
+
   void setHeaders(std::map<std::string, std::string> headers_) override {
     for (auto& header : headers_) {
       headers[header.first] = header.second;  // Overwrite.

vcpkg.json

@@ -0,0 +1,13 @@
+{
+  "name": "dd-opentracing-cpp",
+  "version-string": "1.2.1",
+  "port-version": 0,
+  "homepage": "https://github.com/DataDog/dd-opentracing-cpp",
+  "description": "Datadog OpenTracing C++ Client",
+  "dependencies": [
+    "zlib",
+    "msgpack",
+    "curl",
+    "opentracing"
+  ]
+}