os/linux/elf: avoid using ldd for listing dynamic dependencies

Library/Homebrew/os/linux/elf.rb

@@ -130,19 +130,7 @@ def initialize(path)
  @dylib_id, needed = needed_libraries path
  return if needed.empty?
 
- ldd = DevelopmentTools.locate "ldd"
- ldd_output = Utils.popen_read(ldd, path.expand_path.to_s).split("\n")
- return unless $CHILD_STATUS.success?
-
- ldd_paths = ldd_output.filter_map do |line|
- match = line.match(/\t.+ => (.+) \(.+\)|\t(.+) => not found/)
- next unless match
-
- match.captures.compact.first
- end
- @dylibs = ldd_paths.select do |ldd_path|
- needed.include? File.basename(ldd_path)
- end
+ @dylibs = needed.map { |lib| find_full_lib_path(lib).to_s }
  end
 
  private
@@ -157,6 +145,49 @@ def needed_libraries_using_patchelf_rb(path)
  patcher = path.patchelf_patcher
  [patcher.soname, patcher.needed]
  end
+
+ def ld_so_conf(conf_path = "/etc/ld.so.conf")
+ conf_file = Pathname(conf_path)
+ paths = Set.new
+ directory = conf_file.realpath.dirname
+
+ conf_file.readlines.each do |line|
+ line.rstrip!
+ if line.start_with?(/\s*include\s+/)
+ include_path = Pathname(line.sub(/^\s*include\s+/, "")).expand_path
+ wildcard = include_path.absolute? ? include_path : directory/include_path
+
+ Dir.glob(wildcard.to_s).each do |include_file|
+ paths += ld_so_conf(include_file)
+ end
+ elsif line.start_with?(/\s*#/) || line.empty?
+ next
+ end
+
+ paths << Pathname(line)
+ end
+
+ paths.to_a
+ end
+
+ def find_full_lib_path(basename)
+ local_paths = (path.patchelf_patcher.runpath || path.patchelf_patcher.rpath)&.split(":")&.map do |p|
+ Pathname(p)
+ end
+
+ local_paths&.each do |local_path|
+ candidate = local_path/basename
+ return candidate if candidate.exist? && candidate.elf?
+ end
+
+ global_paths = ld_so_conf
+ global_paths.each do |global_path|
+ candidate = global_path/basename
+ return candidate if candidate.exist? && candidate.elf?
+ end
+
+ basename
+ end
  end
  private_constant :Metadata