feat: add Webassembly support

.gitignore

@@ -30,3 +30,6 @@ compile_commands.json
 /smoke-test-*
 /*.tgz
 /build-artifacts
+.parcel-cache/
+dist/
+*.wasm

CMakeLists.txt

@@ -78,6 +78,200 @@ if(${ZMQ_ENABLE_SANITIZER_UNDEFINED})
   set(ENABLE_SANITIZER_UNDEFINED "ENABLE_SANITIZER_UNDEFINED")
 endif()
 
+option(ZMQ_WASM "Build for WebAssembly" OFF)
+set_option_from_env(ZMQ_WASM)
+
+if(ZMQ_WASM OR CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
+  set(ZMQ_WASM TRUE)
+
+  # Compile for WebAssembly. Keep vcpkg's host triplet native so build tools
+  # run on the host while target libraries are built for Emscripten.
+  set(VCPKG_TARGET_TRIPLET wasm32-emscripten)
+
+  if ("$ENV{EMSCRIPTEN_ROOT}" STREQUAL "")
+    find_program(EMCC emcc REQUIRED)
+    get_filename_component(EMSCRIPTEN_ROOT "${EMCC}" DIRECTORY)
+  else()
+    set(EMSCRIPTEN_ROOT "$ENV{EMSCRIPTEN_ROOT}")
+  endif()
+
+  set(EMSCRIPTEN_PLATFORM_FILE "${EMSCRIPTEN_ROOT}/cmake/Modules/Platform/Emscripten.cmake")
+  if(NOT EXISTS "${EMSCRIPTEN_PLATFORM_FILE}")
+    message(FATAL_ERROR
+      "Could not find the Emscripten CMake platform module at ${EMSCRIPTEN_PLATFORM_FILE}")
+  endif()
+
+  # vcpkg's autotools ports honor CC/CXX from the environment before their
+  # generated target-triplet settings. Ensure target libraries, especially
+  # libsodium, are compiled by Emscripten rather than an inherited host clang.
+  set(ENV{CC} "${EMSCRIPTEN_ROOT}/emcc")
+  set(ENV{CXX} "${EMSCRIPTEN_ROOT}/em++")
+  set(ENV{AR} "${EMSCRIPTEN_ROOT}/emar")
+  set(ENV{RANLIB} "${EMSCRIPTEN_ROOT}/emranlib")
+  set(ENV{NM} "${EMSCRIPTEN_ROOT}/emnm")
+  set(ENV{STRIP} "${EMSCRIPTEN_ROOT}/emstrip")
+  set(ENV{VCPKG_BINARY_SOURCES} "clear")
+
+  # vcpkg includes this chainload exactly once when its toolchain is loaded.
+  set(VCPKG_CHAINLOAD_TOOLCHAIN_FILE "${EMSCRIPTEN_PLATFORM_FILE}"
+    CACHE FILEPATH "Emscripten toolchain chainloaded by vcpkg" FORCE)
+
+  # Use the repository's Emscripten-specific ZeroMQ port overlay. The overlay
+  # patches libzmq's signaler to use a pipe because Emscripten does not provide
+  # an anonymous socketpair in its Node socket backend.
+  set(VCPKG_OVERLAY_PORTS "${CMAKE_SOURCE_DIR}/cmake/vcpkg-overlays"
+    CACHE STRING "vcpkg overlay ports for the WebAssembly target" FORCE)
+
+  add_compile_definitions("-D__wasm__" "-D__EMSCRIPTEN__")
+
+  # export an indirect function table for napi-wasm
+  add_link_options("--export-table")
+
+  # Add WebAssembly-specific exports for napi-wasm
+  add_link_options("SHELL:-s EXPORTED_FUNCTIONS=['_malloc','_free','_napi_wasm_malloc','_napi_register_wasm_v1']")
+  add_link_options("SHELL:-s EXPORTED_RUNTIME_METHODS=['ccall','cwrap']")
+  add_link_options("SHELL:-s ALLOW_MEMORY_GROWTH=1")
+  add_link_options("SHELL:-s ENVIRONMENT='node'")
+  # Keep the signaler's pipe inside the module. The standalone Emscripten
+  # output otherwise leaves pipe2 as a host import, while Node's WASI adapter
+  # only provides the standard WASI descriptors.
+  add_link_options("SHELL:-s WASMFS=1")
+  add_link_options("SHELL:-Wl,--undefined=__syscall_pipe2")
+  # Emscripten's --allow-undefined-file does not allow Node-API imports in
+  # this em++ invocation. Permit unresolved symbols at link time, then expose
+  # the exact module:symbol contract for the post-link audit.
+  add_link_options("SHELL:-s ERROR_ON_UNDEFINED_SYMBOLS=0")
+  add_link_options("SHELL:-s WARN_ON_UNDEFINED_SYMBOLS=1")
+  set(ZMQ_WASM_IMPORT_CONTRACT
+    "napi:napi_add_finalizer"
+    "napi:napi_adjust_external_memory"
+    "napi:napi_async_destroy"
+    "napi:napi_async_init"
+    "napi:napi_call_function"
+    "napi:napi_close_callback_scope"
+    "napi:napi_close_escapable_handle_scope"
+    "napi:napi_close_handle_scope"
+    "napi:napi_coerce_to_object"
+    "napi:napi_coerce_to_string"
+    "napi:napi_create_array_with_length"
+    "napi:napi_create_async_work"
+    "napi:napi_create_buffer"
+    "napi:napi_create_buffer_copy"
+    "napi:napi_create_double"
+    "napi:napi_create_error"
+    "napi:napi_create_external_buffer"
+    "napi:napi_create_function"
+    "napi:napi_create_object"
+    "napi:napi_create_promise"
+    "napi:napi_create_reference"
+    "napi:napi_create_string_latin1"
+    "napi:napi_create_string_utf8"
+    "napi:napi_create_type_error"
+    "napi:napi_define_class"
+    "napi:napi_define_properties"
+    "napi:napi_delete_async_work"
+    "napi:napi_delete_property"
+    "napi:napi_delete_reference"
+    "napi:napi_escape_handle"
+    "napi:napi_fatal_error"
+    "napi:napi_get_and_clear_last_exception"
+    "napi:napi_get_array_length"
+    "napi:napi_get_arraybuffer_info"
+    "napi:napi_get_boolean"
+    "napi:napi_get_cb_info"
+    "napi:napi_get_element"
+    "napi:napi_get_global"
+    "napi:napi_get_last_error_info"
+    "napi:napi_get_named_property"
+    "napi:napi_get_new_target"
+    "napi:napi_get_null"
+    "napi:napi_get_property"
+    "napi:napi_get_reference_value"
+    "napi:napi_get_typedarray_info"
+    "napi:napi_get_undefined"
+    "napi:napi_get_value_bool"
+    "napi:napi_get_value_double"
+    "napi:napi_get_value_int32"
+    "napi:napi_get_value_int64"
+    "napi:napi_get_value_string_utf8"
+    "napi:napi_get_value_uint32"
+    "napi:napi_has_named_property"
+    "napi:napi_has_property"
+    "napi:napi_is_array"
+    "napi:napi_is_arraybuffer"
+    "napi:napi_is_buffer"
+    "napi:napi_is_exception_pending"
+    "napi:napi_new_instance"
+    "napi:napi_open_callback_scope"
+    "napi:napi_open_escapable_handle_scope"
+    "napi:napi_open_handle_scope"
+    "napi:napi_queue_async_work"
+    "napi:napi_reject_deferred"
+    "napi:napi_remove_wrap"
+    "napi:napi_resolve_deferred"
+    "napi:napi_set_element"
+    "napi:napi_set_instance_data"
+    "napi:napi_set_named_property"
+    "napi:napi_throw"
+    "napi:napi_typeof"
+    "napi:napi_unwrap"
+    "napi:napi_wrap"
+    "env:__syscall_accept4"
+    "env:__syscall_bind"
+    "env:__syscall_connect"
+    "env:__syscall_getpeername"
+    "env:__syscall_getsockname"
+    "env:__syscall_getsockopt"
+    "env:__syscall_listen"
+    "env:__syscall_recvfrom"
+    "env:__syscall_rmdir"
+    "env:__syscall_sendto"
+    "env:__syscall_setsockopt"
+    "env:__syscall_socket"
+    "env:__syscall_unlinkat"
+    "env:emscripten_asm_const_int"
+    "env:emscripten_notify_memory_growth"
+    "env:napi_wasm_cancel"
+    "env:napi_wasm_schedule"
+    "env:getaddrinfo"
+    "env:getnameinfo"
+    "env:pthread_setschedparam"
+    "wasi_snapshot_preview1:clock_time_get"
+    "wasi_snapshot_preview1:environ_get"
+    "wasi_snapshot_preview1:environ_sizes_get"
+    "wasi_snapshot_preview1:fd_close"
+    "wasi_snapshot_preview1:fd_read"
+    "wasi_snapshot_preview1:fd_seek"
+    "wasi_snapshot_preview1:fd_write"
+    "wasi_snapshot_preview1:proc_exit"
+    "wasi_snapshot_preview1:random_get"
+  )
+  set(ZMQ_WASM_IMPORT_ALLOWLIST
+    "${CMAKE_CURRENT_BINARY_DIR}/zeromq-wasm-intentional-imports.txt")
+  set(ZMQ_WASM_IMPORT_CONTRACT_FILE
+    "${CMAKE_CURRENT_BINARY_DIR}/zeromq-wasm-import-contract.txt")
+  file(WRITE "${ZMQ_WASM_IMPORT_ALLOWLIST}" "")
+  file(WRITE "${ZMQ_WASM_IMPORT_CONTRACT_FILE}" "")
+  foreach(import_contract IN LISTS ZMQ_WASM_IMPORT_CONTRACT)
+    string(REPLACE ":" ";" import_parts "${import_contract}")
+    list(GET import_parts 1 import_name)
+    file(APPEND "${ZMQ_WASM_IMPORT_ALLOWLIST}" "${import_name}\n")
+    file(APPEND "${ZMQ_WASM_IMPORT_CONTRACT_FILE}" "${import_contract}\n")
+  endforeach()
+  add_link_options("SHELL:--allow-undefined-file=${ZMQ_WASM_IMPORT_ALLOWLIST}")
+  add_link_options("SHELL:-s DISABLE_EXCEPTION_CATCHING=1")
+  add_link_options("--no-entry")
+
+  # The build script stages one current addon, while previous failed builds
+  # can leave copies in versioned cmake-ts output directories. Remove only
+  # those generated addon artifacts so the wildcard copy is deterministic.
+  file(GLOB ZMQ_WASM_STALE_ARTIFACTS
+    "${CMAKE_SOURCE_DIR}/build/wasm32/unknown/node/*/addon.wasm")
+  if(ZMQ_WASM_STALE_ARTIFACTS)
+    file(REMOVE ${ZMQ_WASM_STALE_ARTIFACTS})
+  endif()
+endif()
+
 # Set MacOS deployment target
 if(APPLE)
   option(MACOSX_DEPLOYMENT_TARGET "MacOS deployment target" "10.15")
@@ -130,10 +324,17 @@ project_options(
   ENABLE_CACHE
   ENABLE_COMPILE_COMMANDS_SYMLINK
   ${ENABLE_SANITIZER_UNDEFINED}
+  ENABLE_INTERPROCEDURAL_OPTIMIZATION
 )
 
-file(GLOB_RECURSE SOURCES "./src/*.cc")
-add_library(addon SHARED ${SOURCES})
+file(GLOB_RECURSE SOURCES "./src/*.cc" "./src/*.cpp")
+
+if(ZMQ_WASM)
+  # For WebAssembly, create an executable instead of a shared library
+  add_executable(addon ${SOURCES})
+else()
+  add_library(addon SHARED ${SOURCES})
+endif()
 
 if(CMAKE_CXX_COMPILER_ID STREQUAL GNU
   OR CMAKE_CXX_COMPILER_ID STREQUAL Clang
@@ -151,6 +352,10 @@ if(ZMQ_NO_SYNC_RESOLVE)
   target_compile_definitions(addon PRIVATE ZMQ_NO_SYNC_RESOLVE)
 endif()
 
+if(ZMQ_WASM)
+  target_compile_definitions(addon PRIVATE ZMQ_WASM)
+endif()
+
 # ZeroMQ
 if(ZMQ_SHARED)
   find_package(PkgConfig REQUIRED)
@@ -180,7 +385,21 @@ if(WIN32)
 endif()
 
 # Use `.node` for the library without any "lib" prefix
-set_target_properties(addon PROPERTIES PREFIX "" SUFFIX ".node")
+if(ZMQ_WASM)
+  set_target_properties(addon PROPERTIES PREFIX "" SUFFIX ".wasm")
+
+  find_program(NODE_EXECUTABLE node REQUIRED)
+  add_custom_command(
+    TARGET addon
+    POST_BUILD
+    COMMAND "${NODE_EXECUTABLE}" "${CMAKE_SOURCE_DIR}/script/audit-wasm-imports.mjs"
+      "$<TARGET_FILE:addon>" "${ZMQ_WASM_IMPORT_CONTRACT_FILE}"
+    COMMENT "Auditing WASM imports"
+    VERBATIM
+  )
+else()
+  set_target_properties(addon PROPERTIES PREFIX "" SUFFIX ".node")
+endif()
 
 # Windows delay load node.exe
 if(WIN32)

cmake/vcpkg-overlays/zeromq/fix-arm.patch

@@ -0,0 +1,16 @@
+diff --git a/src/clock.cpp b/src/clock.cpp
+index 79522ad..0667c59 100644
+--- a/src/clock.cpp
++++ b/src/clock.cpp
+@@ -41,8 +41,10 @@
+ #include <cmnintrin.h>
+ #else
+ #include <intrin.h>
+-#if defined(_M_ARM) || defined(_M_ARM64)
++#if defined(_M_ARM)
+ #include <arm_neon.h>
++#elif defined(_M_ARM64)
++#include <arm64_neon.h>
+ #endif
+ #endif
+ #endif

cmake/vcpkg-overlays/zeromq/pkgconfig.diff

@@ -0,0 +1,40 @@
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index 0346227..56d34e6 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -569,6 +569,23 @@ else()
+   check_cxx_symbol_exists(SO_BUSY_POLL sys/socket.h ZMQ_HAVE_BUSY_POLL)
+ endif()
+
++if(WITH_LIBSODIUM)
++  string(APPEND pkg_config_names_private " libsodium")
++endif()
++if(WIN32)
++  string(APPEND pkg_config_libs_private " -ladvapi32 -liphlpapi -lrpcrt4 -lws2_32")
++endif()
++string(APPEND pkg_config_libs_private " ${CMAKE_THREAD_LIBS_INIT}")
++foreach(lib IN LISTS CMAKE_CXX_IMPLICIT_LINK_LIBRARIES)
++  if(lib IN_LIST CMAKE_C_IMPLICIT_LINK_LIBRARIES)
++    continue()
++  elseif(EXISTS "${lib}")
++    string(APPEND pkg_config_libs_private " ${lib}")
++  else()
++    string(APPEND pkg_config_libs_private " -l${lib}")
++  endif()
++endforeach()
++
+ if(NOT MINGW)
+   find_library(RT_LIBRARY rt)
+   if(RT_LIBRARY)
+diff --git a/src/libzmq.pc.in b/src/libzmq.pc.in
+index 233bc3a..3c2bf0d 100644
+--- a/src/libzmq.pc.in
++++ b/src/libzmq.pc.in
+@@ -7,6 +7,6 @@ Name: libzmq
+ Description: 0MQ c++ library
+ Version: @VERSION@
+ Libs: -L${libdir} -lzmq
+-Libs.private: -lstdc++ @pkg_config_libs_private@
++Libs.private: @pkg_config_libs_private@
+ Requires.private: @pkg_config_names_private@
+ Cflags: -I${includedir} @pkg_config_defines@