watcher-rb: first draft of ruby support

watcher-rb/.bundle/config

@@ -0,0 +1,2 @@
+---
+BUNDLE_PATH: "vendor/bundle"

watcher-rb/.gitignore

@@ -0,0 +1,6 @@
+vendor
+tmp
+pkg
+*.gem
+ext/watcher/watcher.cpp
+ext/watcher/wtr

watcher-rb/Gemfile

@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+source 'https://rubygems.org'
+
+gemspec
+
+gem 'rake'
+gem 'rspec'
+gem 'solargraph'
+gem 'standard'

watcher-rb/Gemfile.lock

@@ -0,0 +1,112 @@
+PATH
+  remote: .
+  specs:
+    watcher (0.11.0)
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    ast (2.4.2)
+    backport (1.2.0)
+    benchmark (0.3.0)
+    diff-lcs (1.5.1)
+    e2mmap (0.1.0)
+    jaro_winkler (1.6.0)
+    json (2.7.2)
+    kramdown (2.4.0)
+      rexml
+    kramdown-parser-gfm (1.1.0)
+      kramdown (~> 2.0)
+    language_server-protocol (3.17.0.3)
+    lint_roller (1.1.0)
+    nokogiri (1.16.6-arm64-darwin)
+      racc (~> 1.4)
+    parallel (1.24.0)
+    parser (3.3.4.0)
+      ast (~> 2.4.1)
+      racc
+    racc (1.8.0)
+    rainbow (3.1.1)
+    rake (13.2.1)
+    rbs (2.8.4)
+    regexp_parser (2.9.2)
+    reverse_markdown (2.1.1)
+      nokogiri
+    rexml (3.3.2)
+      strscan
+    rspec (3.13.0)
+      rspec-core (~> 3.13.0)
+      rspec-expectations (~> 3.13.0)
+      rspec-mocks (~> 3.13.0)
+    rspec-core (3.13.0)
+      rspec-support (~> 3.13.0)
+    rspec-expectations (3.13.1)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.13.0)
+    rspec-mocks (3.13.1)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.13.0)
+    rspec-support (3.13.1)
+    rubocop (1.50.2)
+      json (~> 2.3)
+      parallel (~> 1.10)
+      parser (>= 3.2.0.0)
+      rainbow (>= 2.2.2, < 4.0)
+      regexp_parser (>= 1.8, < 3.0)
+      rexml (>= 3.2.5, < 4.0)
+      rubocop-ast (>= 1.28.0, < 2.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (>= 2.4.0, < 3.0)
+    rubocop-ast (1.30.0)
+      parser (>= 3.2.1.0)
+    rubocop-performance (1.16.0)
+      rubocop (>= 1.7.0, < 2.0)
+      rubocop-ast (>= 0.4.0)
+    ruby-progressbar (1.13.0)
+    solargraph (0.50.0)
+      backport (~> 1.2)
+      benchmark
+      bundler (~> 2.0)
+      diff-lcs (~> 1.4)
+      e2mmap
+      jaro_winkler (~> 1.5)
+      kramdown (~> 2.3)
+      kramdown-parser-gfm (~> 1.1)
+      parser (~> 3.0)
+      rbs (~> 2.0)
+      reverse_markdown (~> 2.0)
+      rubocop (~> 1.38)
+      thor (~> 1.0)
+      tilt (~> 2.0)
+      yard (~> 0.9, >= 0.9.24)
+    standard (1.28.5)
+      language_server-protocol (~> 3.17.0.2)
+      lint_roller (~> 1.0)
+      rubocop (~> 1.50.2)
+      standard-custom (~> 1.0.0)
+      standard-performance (~> 1.0.1)
+    standard-custom (1.0.2)
+      lint_roller (~> 1.0)
+      rubocop (~> 1.50)
+    standard-performance (1.0.1)
+      lint_roller (~> 1.0)
+      rubocop-performance (~> 1.16.0)
+    strscan (3.1.0)
+    thor (1.3.1)
+    tilt (2.4.0)
+    unicode-display_width (2.5.0)
+    yard (0.9.36)
+
+PLATFORMS
+  arm64-darwin-23
+
+DEPENDENCIES
+  bundler (~> 2.0)
+  rake
+  rspec
+  solargraph
+  standard
+  watcher!
+
+BUNDLED WITH
+   2.3.26

watcher-rb/Rakefile

@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+require "bundler/gem_tasks"
+require "rspec/core/rake_task"
+
+RSpec::Core::RakeTask.new(:spec)
+
+task build_shared_library: ["lib"] do
+  framework_deps = case RbConfig::CONFIG["host_os"]
+  when /darwin/
+    "-framework CoreServices -framework CoreFoundation"
+  else
+    ""
+  end
+  version = File.read("../.version").strip
+  libname = "libwatcher-c-#{version}.so"
+  sh "c++ -shared -std=c++17 -O2 #{framework_deps} ../watcher-c/src/watcher-c.cpp -I ../watcher-c/include -o lib/#{libname}"
+end
+
+task default: [:clobber, :build_shared_library, :spec]

watcher-rb/bin/watcher

@@ -0,0 +1,15 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+require "watcher"
+
+if ARGV.empty?
+  puts("Usage: watcher <path>")
+  exit(1)
+end
+
+path = ARGV[0]
+watcher = Watcher::Watch.new(path, method(:puts))
+ObjectSpace.define_finalizer(watcher, Watcher::Watch.method(:finalize).to_proc)
+puts("Watching #{path}. Press Enter to stop.")
+gets

watcher-rb/lib/watcher.rb

@@ -0,0 +1,192 @@
+# frozen_string_literal: true
+
+require 'fiddle'
+require 'date'
+
+module Watcher
+  class CEvent < Fiddle::Struct
+    layout(
+      :path_name,
+      :pointer,
+      :effect_type,
+      :int8_t,
+      :path_type,
+      :int8_t,
+      :effect_time,
+      :int64_t,
+      :associated_path_name,
+      :pointer
+    )
+  end
+
+  LIB = nil
+
+  def native_solib_file_ending
+    case RbConfig::CONFIG['host_os']
+    when /darwin/
+      'so'
+    when /mswin|mingw|cygwin/
+      'dll'
+    else
+      'so'
+    end
+  end
+
+  def libwatcher_c_lib_path
+    version = '0.11.0' # hook: tool/release
+    lib_name = "libwatcher-c-#{version}.#{native_solib_file_ending}"
+    lib_path = File.join(File.dirname(__FILE__), lib_name)
+    raise "Library does not exist: '#{lib_path}'" unless File.exist?(lib_path)
+
+    puts("Using library: '#{lib_path}'")
+    lib_path
+  end
+
+  def self.lazy_static_solib_handle
+    return LIB if LIB
+
+    @lib = Fiddle.dlopen(libwatcher_c_lib_path)
+    @lib.extern('void* wtr_watcher_open(char*, void*, void*)')
+    @lib.extern('bool wtr_watcher_close(void*)')
+    @lib
+  end
+
+  def to_utf8
+    return '' if @value.nil?
+    return @value if @value.is_a?(String)
+    return @value.to_s.force_encoding('UTF-8') if @value.respond_to?(:to_s)
+
+    raise TypeError
+  end
+
+  def self.c_event_to_event(c_event)
+    path_name = as_utf8(c_event.path_name.to_s)
+    associated_path_name = as_utf8(c_event.associated_path_name.to_s)
+    effect_type = EffectType.new(c_event.effect_type)
+    path_type = PathType.new(c_event.path_type)
+    effect_time = Time.at(c_event.effect_time / 1e9)
+    Event.new(path_name, effect_type, path_type, effect_time, associated_path_name)
+  end
+
+  class EffectType
+    RENAME = 0
+    MODIFY = 1
+    CREATE = 2
+    DESTROY = 3
+    OWNER = 4
+    OTHER = 5
+
+    def initialize(value)
+      @value = value
+    end
+
+    def to_s
+      case @value
+      when RENAME
+        'RENAME'
+      when MODIFY
+        'MODIFY'
+      when CREATE
+        'CREATE'
+      when DESTROY
+        'DESTROY'
+      when OWNER
+        'OWNER'
+      when OTHER
+        'OTHER'
+      else
+        'UNKNOWN'
+      end
+    end
+  end
+
+  class PathType
+    DIR = 0
+    FILE = 1
+    HARD_LINK = 2
+    SYM_LINK = 3
+    WATCHER = 4
+    OTHER = 5
+
+    def initialize(value)
+      @value = value
+    end
+
+    def to_s
+      case @value
+      when DIR
+        'DIR'
+      when FILE
+        'FILE'
+      when HARD_LINK
+        'HARD_LINK'
+      when SYM_LINK
+        'SYM_LINK'
+      when WATCHER
+        'WATCHER'
+      when OTHER
+        'OTHER'
+      else
+        'UNKNOWN'
+      end
+    end
+  end
+
+  class Event
+    attr_reader :path_name, :effect_type, :path_type, :effect_time, :associated_path_name
+
+    def initialize(path_name, effect_type, path_type, effect_time, associated_path_name)
+      @path_name = path_name
+      @effect_type = effect_type
+      @path_type = path_type
+      @effect_time = effect_time
+      @associated_path_name = associated_path_name
+    end
+
+    def to_s
+      pnm = "path_name: #{@path_name}"
+      ety = "effect_type: #{@effect_type}"
+      pty = "path_type: #{@path_type}"
+      etm = "effect_time: #{@effect_time}"
+      apn = "associated_path_name: #{@associated_path_name}"
+      "Event(#{pnm}, #{ety}, #{pty}, #{etm}, #{apn})"
+    end
+  end
+
+  class Watch
+    def initialize(path, callback)
+      @lib = Watcher.lazy_static_solib_handle
+      @path = path.encode('UTF-8')
+      @callback = callback
+      @c_callback = Fiddle::Closure::BlockCaller.new(0, [CEvent, :void]) do |c_event, _|
+        py_event = Watcher.c_event_to_event(c_event)
+        @callback.call(py_event)
+      end
+
+      @watcher = @lib.wtr_watcher_open(@path, @c_callback, nil)
+      raise 'Failed to open a watcher' unless @watcher
+    end
+
+    def close
+      return unless @watcher
+
+      @lib.wtr_watcher_close(@watcher)
+      @watcher = nil
+    end
+
+    def finalize
+      close
+    end
+
+    def self.finalize(id)
+      ObjectSpace._id2ref(id).close
+    end
+  end
+end
+
+if __FILE__ == $PROGRAM_NAME
+  events_at = ARGV[0] || '.'
+  watcher = Watcher::Watch.new(events_at, method(:puts))
+  ObjectSpace.define_finalizer(watcher, Watcher::Watch.method(:finalize).to_proc)
+  gets
+end

watcher-rb/tool/build

@@ -0,0 +1,7 @@
+#! /usr/bin/env bash
+set -e
+cd "$(dirname "$0")/.."
+bundle install
+bundle exec rake
+bundle exec gem build watcher.gemspec
+bundle exec gem install watcher-*.gem

watcher-rb/watcher.gemspec

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+Gem::Specification.new do |spec|
+  spec.name = 'watcher'
+  spec.version = File.read('../.version').strip
+  spec.authors = ['Will']
+  spec.email = ['[email protected]']
+  spec.summary = 'Filesystem watcher. Simple, efficient and friendly.'
+  spec.description = 'Watch events on (almost) any filesystem.'
+  spec.homepage = 'https://github.com/e-dant/watcher'
+  spec.license = 'MIT'
+  spec.required_ruby_version = Gem::Requirement.new('>= 2.7.0')
+  spec.metadata['homepage_uri'] = spec.homepage
+  spec.metadata['changelog_uri'] = "#{spec.homepage}/changelog.md"
+  spec.metadata['allowed_push_host'] = 'TODO'
+  spec.files = `ls -1 lib`.split("\n").map { |f| "lib/#{f}" }
+  spec.bindir = 'bin'
+  spec.executables = 'watcher'
+  spec.require_paths = ['lib']
+  spec.add_development_dependency 'bundler', '~> 2.0'
+  spec.add_development_dependency 'rake', '~> 13.0'
+  spec.add_development_dependency 'rspec', '~> 3.0'
+end