lsof: package the upstream open-file inspector

Formula/lsof.rb

@@ -0,0 +1,78 @@
+require_relative "../Kandelo/formula_support/kandelo_formula_support"
+
+class Lsof < Formula
+  include KandeloFormulaSupport
+
+  desc "Utility to list open files inside Kandelo"
+  homepage "https://github.com/lsof-org/lsof"
+  url "https://github.com/lsof-org/lsof/archive/refs/tags/4.99.7.tar.gz"
+  sha256 "bac1b0acbc50aede42fc97dffaa0b0475e97973e36a6351de5f349c6155afc68"
+  license "lsof"
+
+  skip_clean "bin/lsof"
+
+  def install
+    kandelo_require_arch!("wasm32")
+
+    kandelo_wasm_build do |root|
+      # Kandelo intentionally does not expose Linux AF_PACKET or AF_NETLINK
+      # UAPI. Upstream only uses these headers for optional, guarded names.
+      inreplace "lib/dialects/linux/dlsof.h" do |s|
+        s.gsub! <<~OLD, <<~NEW
+          #    include <linux/if_ether.h>
+          #    include <linux/netlink.h>
+        OLD
+          #    if defined(__has_include)
+          #        if __has_include(<linux/if_ether.h>)
+          #            include <linux/if_ether.h>
+          #        endif
+          #        if __has_include(<linux/netlink.h>)
+          #            include <linux/netlink.h>
+          #        endif
+          #    else
+          #        include <linux/if_ether.h>
+          #        include <linux/netlink.h>
+          #    endif
+        NEW
+      end
+
+      include_dir = "#{ENV.fetch("WASM_POSIX_SYSROOT")}/include"
+      ENV["LSOF_CC"] = kandelo_cc(root)
+      ENV["LINUX_CONF_CC"] = kandelo_cc(root)
+      ENV["LSOF_CCV"] = ENV.cc
+      ENV["LSOF_INCLUDE"] = include_dir
+      ENV["LINUX_INCL"] = include_dir
+      ENV["LINUX_VERSION_CODE"] = "393216" # Linux 6.0 procfs compatibility level.
+      ENV["LINUX_CLIB"] = "-U__GLIBC__"
+      ENV["LSOF_AR"] = "#{kandelo_ar(root)} cr"
+      ENV["LSOF_RANLIB"] = kandelo_ranlib(root)
+      ENV["LSOF_MAKE"] = "make"
+
+      system "./Configure", "-n", "linux"
+      system "make", "-j#{ENV.make_jobs}"
+      kandelo_fork_instrument(buildpath/"lsof")
+    end
+
+    kandelo_install_bin(buildpath, "lsof", "lsof")
+    man8.install "Lsof.8" => "lsof.8"
+  end
+
+  test do
+    version_output = kandelo_run_wasm(bin/"lsof", ["-v"], merge_stderr: true)
+    assert_match(/revision: 4\.99\.7$/, version_output)
+
+    workdir = testpath/"working-directory"
+    workdir.mkpath
+    fields = kandelo_run_wasm(
+      bin/"lsof",
+      ["-nP", "-a", "-p", "100", "-d", "cwd,0-2", "-Fpcfnt"],
+      env: { "KERNEL_CWD" => workdir },
+    )
+    assert_match(/^p100$/, fields)
+    assert_match(/^clsof\.wasm$/, fields)
+    assert_match(/^fcwd\ntDIR\nn#{Regexp.escape(workdir.to_s)}$/, fields)
+    assert_match(%r{^f0\nn/dev/stdin$}, fields)
+    assert_match(%r{^f1\nn/dev/stdout$}, fields)
+    assert_match(%r{^f2\nn/dev/stderr$}, fields)
+  end
+end

README.md

@@ -29,6 +29,7 @@ Current migration controls and pilots include:
 - `sed`, the GNU stream-editing CLI used by shell and build workflows;
 - `gzip`, the GNU compression CLI with native gunzip and zcat aliases;
 - `grep`, GNU regular-expression and file search for the leaf CLI wave.
+- `lsof`, the upstream process and open-file inspector backed by Kandelo procfs.
 
 The SDK is not yet a Homebrew dependency. Trusted builds supply an
 `HOMEBREW_KANDELO_ROOT` checkout containing the SDK, sysroot, kernel, and Node