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require_relative '../explicit_require'
module Bootsnap
module LoadPathCache
class Cache
AGE_THRESHOLD = 30 # seconds
def initialize(store, path_obj, development_mode: false)
@development_mode = development_mode
@store = store
@mutex = defined?(::Mutex) ? ::Mutex.new : ::Thread::Mutex.new # TODO: Remove once Ruby 2.2 support is dropped.
@path_obj = path_obj.map! { |f| File.exist?(f) ? File.realpath(f) : f }
@has_relative_paths = nil
reinitialize
end
# Does this directory exist as a child of one of the path items?
# e.g. given "/a/b/c/d" exists, and the path is ["/a/b"], has_dir?("c/d")
# is true.
def has_dir?(dir)
reinitialize if stale?
@mutex.synchronize { @dirs[dir] }
end
# { 'enumerator' => nil, 'enumerator.so' => nil, ... }
BUILTIN_FEATURES = $LOADED_FEATURES.each_with_object({}) do |feat, features|
# Builtin features are of the form 'enumerator.so'.
# All others include paths.
next unless feat.size < 20 && !feat.include?('/')
base = File.basename(feat, '.*') # enumerator.so -> enumerator
ext = File.extname(feat) # .so
features[feat] = nil # enumerator.so
features[base] = nil # enumerator
next unless [DOT_SO, *DL_EXTENSIONS].include?(ext)
DL_EXTENSIONS.each do |dl_ext|
features["#{base}#{dl_ext}"] = nil # enumerator.bundle
end
end.freeze
# Try to resolve this feature to an absolute path without traversing the
# loadpath.
def find(feature)
reinitialize if (@has_relative_paths && dir_changed?) || stale?
feature = feature.to_s
return feature if absolute_path?(feature)
return File.expand_path(feature) if feature.start_with?('./')
@mutex.synchronize do
x = search_index(feature)
return x if x
# Ruby has some built-in features that require lies about.
# For example, 'enumerator' is built in. If you require it, ruby
# returns false as if it were already loaded; however, there is no
# file to find on disk. We've pre-built a list of these, and we
# return false if any of them is loaded.
raise LoadPathCache::ReturnFalse if BUILTIN_FEATURES.key?(feature)
# The feature wasn't found on our preliminary search through the index.
# We resolve this differently depending on what the extension was.
case File.extname(feature)
# If the extension was one of the ones we explicitly cache (.rb and the
# native dynamic extension, e.g. .bundle or .so), we know it was a
# failure and there's nothing more we can do to find the file.
# no extension, .rb, (.bundle or .so)
when '', *CACHED_EXTENSIONS # rubocop:disable Performance/CaseWhenSplat
nil
# Ruby allows specifying native extensions as '.so' even when DLEXT
# is '.bundle'. This is where we handle that case.
when DOT_SO
x = search_index(feature[0..-4] + DLEXT)
return x if x
if DLEXT2
search_index(feature[0..-4] + DLEXT2)
end
else
# other, unknown extension. For example, `.rake`. Since we haven't
# cached these, we legitimately need to run the load path search.
raise LoadPathCache::FallbackScan
end
end
end
if RbConfig::CONFIG['host_os'] =~ /mswin|mingw|cygwin/
def absolute_path?(path)
path[1] == ':'
end
else
def absolute_path?(path)
path.start_with?(SLASH)
end
end
def unshift_paths(sender, *paths)
return unless sender == @path_obj
@mutex.synchronize { unshift_paths_locked(*paths) }
end
def push_paths(sender, *paths)
return unless sender == @path_obj
@mutex.synchronize { push_paths_locked(*paths) }
end
def reinitialize(path_obj = @path_obj)
@mutex.synchronize do
@path_obj = path_obj
ChangeObserver.register(self, @path_obj)
@index = {}
@dirs = Hash.new(false)
@generated_at = now
push_paths_locked(*@path_obj)
end
end
private
def dir_changed?
@prev_dir ||= Dir.pwd
if @prev_dir == Dir.pwd
false
else
@prev_dir = Dir.pwd
true
end
end
def push_paths_locked(*paths)
@store.transaction do
paths.map(&:to_s).each do |path|
p = Path.new(path)
@has_relative_paths = true if p.relative?
next if p.non_directory?
entries, dirs = p.entries_and_dirs(@store)
# push -> low precedence -> set only if unset
dirs.each { |dir| @dirs[dir] ||= true }
entries.each { |rel| @index[rel] ||= p.expanded_path }
end
end
end
def unshift_paths_locked(*paths)
@store.transaction do
paths.map(&:to_s).reverse_each do |path|
p = Path.new(path)
next if p.non_directory?
entries, dirs = p.entries_and_dirs(@store)
# unshift -> high precedence -> unconditional set
dirs.each { |dir| @dirs[dir] = true }
entries.each { |rel| @index[rel] = p.expanded_path }
end
end
end
def stale?
@development_mode && @generated_at + AGE_THRESHOLD < now
end
def now
Process.clock_gettime(Process::CLOCK_MONOTONIC).to_i
end
if DLEXT2
def search_index(f)
try_index(f + DOT_RB) || try_index(f + DLEXT) || try_index(f + DLEXT2) || try_index(f)
end
else
def search_index(f)
try_index(f + DOT_RB) || try_index(f + DLEXT) || try_index(f)
end
end
def try_index(f)
if p = @index[f]
p + '/' + f
end
end
end
end
end