plugins: add ZeroBus output plugin

CMakeLists.txt

@@ -1369,6 +1369,12 @@ if(FLB_OUT_PGSQL AND (NOT PostgreSQL_FOUND))
    FLB_OPTION(FLB_OUT_PGSQL OFF)
 endif()
 
+# ZeroBus FFI
+# ===========
+if(FLB_OUT_ZEROBUS)
+  include(cmake/zerobus-ffi.cmake)
+endif()
+
 # Arrow GLib
 # ==========
 find_package(PkgConfig)

cmake/plugins_options.cmake

@@ -155,3 +155,4 @@ DEFINE_OPTION(FLB_OUT_TCP                     "Enable TCP output plugin"
 DEFINE_OPTION(FLB_OUT_UDP                     "Enable UDP output plugin"                     ON)
 DEFINE_OPTION(FLB_OUT_VIVO_EXPORTER           "Enable Vivo exporter output plugin"           ON)
 DEFINE_OPTION(FLB_OUT_WEBSOCKET               "Enable Websocket output plugin"               ON)
+DEFINE_OPTION(FLB_OUT_ZEROBUS                 "Enable Databricks ZeroBus output plugin"      ON)

cmake/zerobus-ffi.cmake

@@ -0,0 +1,95 @@
+# Set up the ZeroBus FFI prebuilt static library.
+#
+# If ZEROBUS_LIB_DIR is already set by the user, that path is used as-is.
+# Otherwise the official release tarball is downloaded and the correct
+# platform subdirectory is selected automatically.
+#
+# On unsupported platforms or when the download fails, the plugin is
+# disabled automatically (FLB_OUT_ZEROBUS is set to OFF).
+#
+# After this module runs, ZEROBUS_LIB_DIR points to the directory
+# containing libzerobus_ffi.a for the current platform.
+
+if(ZEROBUS_LIB_DIR)
+  return()
+endif()
+
+set(_ZEROBUS_URL
+  "https://github.com/databricks/zerobus-sdk/releases/download/ffi-v1.0.0/zerobus-ffi-1.0.0.tar.gz")
+set(_ZEROBUS_SHA256
+  "c38609f5bddc160b43b35f9047919b35f66375308be69a0d0d6cd20bc01cee5a")
+
+# Determine the platform subdirectory inside the tarball
+if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+  if(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64|ARM64")
+    set(_ZEROBUS_PLATFORM "linux-aarch64")
+  elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "x86_64|AMD64")
+    set(_ZEROBUS_PLATFORM "linux-x86-64")
+  else()
+    message(STATUS
+      "ZeroBus FFI: unsupported Linux architecture '${CMAKE_SYSTEM_PROCESSOR}', "
+      "disabling out_zerobus. "
+      "To build manually, set -DZEROBUS_LIB_DIR=/path/to/lib.")
+    FLB_OPTION(FLB_OUT_ZEROBUS OFF)
+    return()
+  endif()
+else()
+  message(STATUS
+    "ZeroBus FFI: no prebuilt library available for ${CMAKE_SYSTEM_NAME}, "
+    "disabling out_zerobus. "
+    "To build manually, set -DZEROBUS_LIB_DIR=/path/to/lib.")
+  FLB_OPTION(FLB_OUT_ZEROBUS OFF)
+  return()
+endif()
+
+# Download the tarball if not already cached
+set(_ZEROBUS_TARBALL "${CMAKE_BINARY_DIR}/zerobus-ffi-1.0.0.tar.gz")
+if(NOT EXISTS "${_ZEROBUS_TARBALL}")
+  message(STATUS "ZeroBus FFI: downloading ${_ZEROBUS_URL}")
+  file(DOWNLOAD
+    "${_ZEROBUS_URL}"
+    "${_ZEROBUS_TARBALL}"
+    EXPECTED_HASH "SHA256=${_ZEROBUS_SHA256}"
+    SHOW_PROGRESS
+    STATUS _DOWNLOAD_STATUS
+  )
+  list(GET _DOWNLOAD_STATUS 0 _DOWNLOAD_ERROR)
+  if(_DOWNLOAD_ERROR)
+    message(STATUS
+      "ZeroBus FFI: download failed (${_DOWNLOAD_STATUS}), "
+      "disabling out_zerobus. "
+      "To build manually, set -DZEROBUS_LIB_DIR=/path/to/lib.")
+    file(REMOVE "${_ZEROBUS_TARBALL}")
+    FLB_OPTION(FLB_OUT_ZEROBUS OFF)
+    return()
+  endif()
+endif()
+
+# Extract the tarball
+set(_ZEROBUS_EXTRACT_DIR "${CMAKE_BINARY_DIR}")
+if(NOT EXISTS "${_ZEROBUS_EXTRACT_DIR}/native")
+  execute_process(
+    COMMAND ${CMAKE_COMMAND} -E tar xzf "${_ZEROBUS_TARBALL}"
+    WORKING_DIRECTORY "${CMAKE_BINARY_DIR}"
+    RESULT_VARIABLE _EXTRACT_RESULT
+  )
+  if(_EXTRACT_RESULT)
+    message(STATUS
+      "ZeroBus FFI: extraction failed, disabling out_zerobus.")
+    FLB_OPTION(FLB_OUT_ZEROBUS OFF)
+    return()
+  endif()
+endif()
+
+set(ZEROBUS_LIB_DIR "${_ZEROBUS_EXTRACT_DIR}/native/${_ZEROBUS_PLATFORM}"
+    CACHE PATH "Path to ZeroBus FFI library directory" FORCE)
+
+if(NOT EXISTS "${ZEROBUS_LIB_DIR}/libzerobus_ffi.a")
+  message(STATUS
+    "ZeroBus FFI: libzerobus_ffi.a not found at ${ZEROBUS_LIB_DIR}, "
+    "disabling out_zerobus.")
+  FLB_OPTION(FLB_OUT_ZEROBUS OFF)
+  return()
+endif()
+
+message(STATUS "ZeroBus FFI library: ${ZEROBUS_LIB_DIR}/libzerobus_ffi.a")

plugins/CMakeLists.txt

@@ -413,6 +413,7 @@ REGISTER_OUT_PLUGIN("out_prometheus_remote_write")
 REGISTER_OUT_PLUGIN("out_s3")
 REGISTER_OUT_PLUGIN("out_vivo_exporter")
 REGISTER_OUT_PLUGIN("out_chronicle")
+REGISTER_OUT_PLUGIN("out_zerobus")
 
 if(FLB_ZIG)
 REGISTER_OUT_PLUGIN("out_zig_demo" "zig")

plugins/out_zerobus/CMakeLists.txt

@@ -0,0 +1,29 @@
+set(src
+  zerobus.c)
+
+FLB_PLUGIN(out_zerobus "${src}" "")
+
+# ZEROBUS_LIB_DIR is set automatically by cmake/zerobus-ffi.cmake or
+# can be overridden by the user via -DZEROBUS_LIB_DIR=/path/to/lib.
+if(NOT ZEROBUS_LIB_DIR)
+  message(FATAL_ERROR
+    "ZEROBUS_LIB_DIR is not set. This should not happen when "
+    "FLB_OUT_ZEROBUS is ON — check that cmake/zerobus-ffi.cmake is included.")
+endif()
+
+target_link_libraries(flb-plugin-out_zerobus ${ZEROBUS_LIB_DIR}/libzerobus_ffi.a)
+
+# Platform-specific linker flags required by the Rust FFI static library
+if(WIN32)
+  message(FATAL_ERROR
+    "out_zerobus does not support Windows builds. "
+    "Disable it with -DFLB_OUT_ZEROBUS=OFF")
+elseif(APPLE)
+  target_link_libraries(flb-plugin-out_zerobus
+    "-framework CoreFoundation"
+    "-framework Security"
+    -liconv)
+elseif(UNIX)
+  target_link_libraries(flb-plugin-out_zerobus
+    -ldl -lpthread -lm -lresolv -lgcc_s)
+endif()