W3C-style trace context propagation (#13)

Author: dgoffredo

.circleci/config.yml

@@ -10,6 +10,14 @@ jobs:
     - checkout
     - run: bin/check-format
 
+  shellcheck:
+    docker:
+    - image: "datadog/docker-library:dd-trace-cpp-ci"
+    resource_class: small
+    steps:
+    - checkout
+    - run: find bin/ -executable -type f | xargs shellcheck
+
   build-bazel:
     parameters:
       toolchain:
@@ -59,6 +67,7 @@ workflows:
   pull-request:
     jobs:
     - format
+    - shellcheck
     - test-cmake:
         matrix:
           parameters:

BUILD.bazel

@@ -16,7 +16,9 @@ cc_library(
     "src/datadog/error.cpp",
     "src/datadog/event_scheduler.cpp",
     "src/datadog/expected.cpp",
+    "src/datadog/extracted_data.cpp",
     "src/datadog/glob.cpp",
+    "src/datadog/hex.cpp",
     "src/datadog/http_client.cpp",
     "src/datadog/id_generator.cpp",
     "src/datadog/limiter.cpp",
@@ -49,6 +51,7 @@ cc_library(
     "src/datadog/trace_sampler.cpp",
     "src/datadog/trace_segment.cpp",
     "src/datadog/version.cpp",
+    "src/datadog/w3c_propagation.cpp",
     ],
     hdrs = [
     "src/datadog/cerr_logger.h",
@@ -65,7 +68,9 @@ cc_library(
     "src/datadog/error.h",
     "src/datadog/event_scheduler.h",
     "src/datadog/expected.h",
+    "src/datadog/extracted_data.h",
     "src/datadog/glob.h",
+    "src/datadog/hex.h",
     "src/datadog/http_client.h",
     "src/datadog/id_generator.h",
     "src/datadog/json.hpp",
@@ -100,6 +105,7 @@ cc_library(
     "src/datadog/trace_sampler.h",
     "src/datadog/trace_segment.h",
     "src/datadog/version.h",
+    "src/datadog/w3c_propagation.h",
     ],
     copts = [
         "-Wall",

CMakeLists.txt

@@ -8,6 +8,7 @@ option(BUILD_COVERAGE "Build code with code coverage profiling instrumentation"
 option(BUILD_EXAMPLE "Build the example program (example/)" OFF)
 option(BUILD_TESTING "Build the unit tests (test/)" OFF)
 option(SANITIZE "Build with address sanitizer and undefined behavior sanitizer" OFF)
+option(FUZZ_W3C_PROPAGATION "Build a fuzzer for W3C propagation" OFF)
 
 set(CMAKE_BUILD_TYPE "RelWithDebInfo")
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
@@ -20,12 +21,26 @@ include(ProcessorCount)
 ProcessorCount(NUM_PROCESSORS)
 set(MAKE_JOB_COUNT ${NUM_PROCESSORS} CACHE STRING "Number of jobs to use when building libcurl")
 
-if (SANITIZE)
+function(add_sanitizers)
   add_compile_options(-fsanitize=address)
   add_link_options(-fsanitize=address)
   add_compile_options(-fsanitize=undefined)
   add_link_options(-fsanitize=undefined)
-  # Thread sanitizer fails with "unexpected memory mapping".
+endfunction()
+
+if(FUZZ_W3C_PROPAGATION)
+  add_compile_options(-fsanitize=fuzzer)
+  add_link_options(-fsanitize=fuzzer)
+  add_sanitizers()
+  add_subdirectory(fuzz/w3c-propagation)
+endif()
+
+if (SANITIZE)
+  add_sanitizers()
+endif()
+
+if (BUILD_TESTING)
+  set(CMAKE_BUILD_TYPE "Debug")
 endif()
 
 include (ExternalProject)
@@ -70,7 +85,9 @@ target_sources(dd_trace_cpp PRIVATE
     src/datadog/error.cpp
     src/datadog/event_scheduler.cpp
     src/datadog/expected.cpp
+    src/datadog/extracted_data.cpp
     src/datadog/glob.cpp
+    src/datadog/hex.cpp
     src/datadog/http_client.cpp
     src/datadog/id_generator.cpp
     src/datadog/limiter.cpp
@@ -103,6 +120,7 @@ target_sources(dd_trace_cpp PRIVATE
     src/datadog/trace_sampler.cpp
     src/datadog/trace_segment.cpp
     src/datadog/version.cpp
+    src/datadog/w3c_propagation.cpp
 )
 
 # This library's public headers are just its source headers.
@@ -125,7 +143,9 @@ target_sources(dd_trace_cpp PUBLIC
   src/datadog/error.h
   src/datadog/event_scheduler.h
   src/datadog/expected.h
+  src/datadog/extracted_data.h
   src/datadog/glob.h
+  src/datadog/hex.h
   src/datadog/http_client.h
   src/datadog/id_generator.h
   src/datadog/json_fwd.hpp
@@ -160,6 +180,7 @@ target_sources(dd_trace_cpp PUBLIC
   src/datadog/trace_sampler.h
   src/datadog/trace_segment.h
   src/datadog/version.h
+  src/datadog/w3c_propagation.h
 )
 
 add_dependencies(dd_trace_cpp curl)

Dockerfile

@@ -14,7 +14,7 @@ env DEBIAN_FRONTEND=noninteractive
 run apt-get update && apt-get install --yes software-properties-common && \
     add-apt-repository ppa:git-core/ppa --yes && \
     apt-get update && apt-get upgrade --yes && \
-    apt-get install --yes wget build-essential clang sed gdb clang-format git ssh
+    apt-get install --yes wget build-essential clang sed gdb clang-format git ssh shellcheck
 
 # bazelisk, a launcher for bazel. `bazelisk --help` will cause the latest
 # version to be downloaded.

bin/bazel-build

@@ -2,6 +2,6 @@
 
 set -e
 
-cd $(dirname "$0")/..
+cd "$(dirname "$0")"/..
 
 bazelisk build dd_trace_cpp

bin/check

@@ -0,0 +1,13 @@
+#!/bin/sh
+
+# Run some of the checks that are performed by CircleCI.
+# This is convenient to run before committing.
+
+set -e
+
+# Go to the repository root directory.
+cd "$(dirname "$0")"/..
+
+bin/format --dry-run -Werror
+bin/test
+bin/bazel-build

bin/cmake-build

@@ -2,9 +2,9 @@
 
 set -e
 
-cd $(dirname "$0")/..
+cd "$(dirname "$0")"/..
 
 mkdir -p .build
 cd .build
 cmake ..
-make -j $(nproc)
+make -j "$(nproc)"

bin/example

@@ -19,8 +19,9 @@ cd "$(dirname "$0")"/..
 
 mkdir -p .build
 cd .build
-cmake .. $coverage_flags -DBUILD_EXAMPLE=1
-make -j $(nproc) $verbosity_flags
+cmake .. -DBUILD_EXAMPLE=1
+# shellcheck disable=SC2086
+make -j "$(nproc)" $verbosity_flags
 
 if [ "$build_only" -eq 1 ]; then
     exit
@@ -35,6 +36,6 @@ if [ "$DD_API_KEY" = '' ]; then
 fi
 docker compose --project-directory ../example up --detach --remove-orphans
 # docker compose --project-directory ../example logs --follow &
-./example/example"$@"
+./example/example "$@"
 docker compose --project-directory ../example down
 # wait

bin/format

@@ -1,5 +1,7 @@
 #!/bin/sh
 
+set -e
+
 # Go to the repository root directory.
 cd "$(dirname "$0")"/..
 
@@ -9,14 +11,15 @@ cd "$(dirname "$0")"/..
 # occasionally bumps the required version, reformatting everything.
 version=14
 formatter=clang-format-$version
-formatter_options='--style=file -i'
+formatter_options="--style=file -i"
 
 find_sources() {
-    find src/ example/ test/ -type f \( -name '*.h' -o -name '*.cpp' \) "$@"
+    find src/ example/ test/ fuzz/ -type f \( -name '*.h' -o -name '*.cpp' \) "$@"
 }
 
 # If the correct version of clang-format is installed, then use it and quit.
 if >/dev/null command -v "$formatter"; then
+    # shellcheck disable=SC2086
     find_sources -print0 | xargs -0 "$formatter" $formatter_options
     exit
 fi
@@ -31,11 +34,11 @@ fi
 image=silkeh/clang:$version
 if [ "$(docker image ls --quiet $image | wc -l)" -eq 0 ]; then
     printf '%s is not installed. Download docker image %s instead? [Y/n] ' "$formatter" "$image"
-    read response
+    read -r response
     case "$response" in
         y|Y|yes|Yes|YES|'') ;;
         *) exit ;;
-    esac 
+    esac
 fi
 
 mount_path=/mnt/host
@@ -52,6 +55,7 @@ process_arg() {
 }
 
 docker_clang_format() {
+    # shellcheck disable=SC2086
     find_sources | while IFS= read -r arg; do
         process_arg "$arg"
     done | xargs -0 \

bin/install-cmake

@@ -1,5 +1,7 @@
 #!/bin/sh
 
+set -e
+
 # Install a recent binary release of cmake.
 # Kitware produces a self-installing tarball.