Files
extism/ruby/lib/extism.rb

79 lines
2.4 KiB
Ruby

require 'ffi'
require 'json'
module Extism
module C
extend FFI::Library
ffi_lib "extism"
attach_function :extism_plugin_register, [:pointer, :uint64, :bool], :int32
attach_function :extism_plugin_update, [:int32, :pointer, :uint64, :bool], :bool
attach_function :extism_error, [:int32], :string
attach_function :extism_call, [:int32, :string, :pointer, :uint64], :int32
attach_function :extism_output_length, [:int32], :uint64
attach_function :extism_output_get, [:int32], :pointer
attach_function :extism_log_file, [:string, :pointer], :void
end
class Error < StandardError
end
def self.set_log_file(name, level=nil)
if level then
level = FFI::MemoryPointer::from_string(level)
end
C.extism_log_file(name, level)
end
class Plugin
def initialize(wasm, wasi=false, config=nil)
if wasm.class == Hash then
wasm = JSON.generate(wasm)
end
code = FFI::MemoryPointer.new(:char, wasm.bytesize)
code.put_bytes(0, wasm)
@plugin = C.extism_plugin_register(code, wasm.bytesize, wasi)
if config != nil and @plugin >= 0 then
s = JSON.generate(config)
ptr = FFI::MemoryPointer::from_string(s)
C.extism_plugin_config(@plugin, ptr, s.bytesize)
end
end
def update(wasm, wasi=false, config=nil)
if wasm.class == Hash then
wasm = JSON.generate(wasm)
end
code = FFI::MemoryPointer.new(:char, wasm.bytesize)
code.put_bytes(0, wasm)
ok = C.extism_plugin_update(@plugin, code, wasm.bytesize, wasi)
if ok then
if config != nil then
s = JSON.generate(config)
ptr = FFI::MemoryPointer::from_string(s)
C.extism_plugin_config(@plugin, ptr, s.bytesize)
end
end
return ok
end
def call(name, data, &block)
# If no block was passed then use Pointer::read_string
block ||= ->(buf, len){ buf.read_string(len) }
input = FFI::MemoryPointer::from_string(data)
rc = C.extism_call(@plugin, name, input, data.bytesize)
if rc != 0 then
err = C.extism_error(@plugin)
if err&.empty? then
raise Error.new "extism_call failed"
else raise Error.new err
end
end
out_len = C.extism_output_length(@plugin)
buf = C.extism_output_get(@plugin)
return block.call(buf, out_len)
end
end
end