From bace7379b74f92891eacf29143a329018029b887 Mon Sep 17 00:00:00 2001
From: Qyriad <qyriad@qyriad.me>
Date: Sat, 9 Mar 2024 20:29:51 -0700
Subject: [PATCH] meson: generate a config.h that works with the current build
 system

Change-Id: I578982fdfc34af1f24ad0c1335dcd7bdef01fd9d
---
 meson.build   | 153 ++++++++++++++++++++++++++++++++++++++++++++++++++
 meson.options |  16 ++++++
 package.nix   |   6 ++
 3 files changed, 175 insertions(+)
 create mode 100644 meson.build
 create mode 100644 meson.options

diff --git a/meson.build b/meson.build
new file mode 100644
index 000000000..a962e028a
--- /dev/null
+++ b/meson.build
@@ -0,0 +1,153 @@
+project('lix', 'cpp',
+  version : run_command('bash', '-c', 'echo -n $(cat ./.version)$VERSION_SUFFIX', check : true).stdout().strip(),
+  default_options : [
+    'buildtype=debugoptimized',
+    'cpp_std=c++20',
+  ],
+)
+
+cxx = meson.get_compiler('cpp')
+
+host_system = host_machine.cpu_family() + '-' + host_machine.system()
+message('canonical Nix system name:', host_system)
+
+deps = [ ]
+configdata = { }
+#'AWS_VERSION_MAJOR': aws_sdk_version_major,
+#'AWS_VERSION_MINOR': aws_sdk_version_minor,
+#'AWS_VERSION_PATCH': aws_sdk_version_patch,
+#'CAN_LINK_SYMLINK': can_link_symlink.to_int(),
+
+aws_sdk = dependency('aws-cpp-sdk-core', required : false)
+if aws_sdk.found()
+  deps += aws_sdk
+  s = aws_sdk.version().split('.')
+  configdata += {
+    'AWS_VERSION_MAJOR': s[0].to_int(),
+    'AWS_VERSION_MINOR': s[1].to_int(),
+    'AWS_VERSION_PATCH': s[2].to_int(),
+  }
+endif
+aws_s3 = dependency('aws-cpp-sdk-s3', required : false)
+configdata += {
+  'ENABLE_S3': aws_s3.found().to_int(),
+}
+if aws_s3.found()
+  deps += aws_s3
+endif
+
+run_command('ln', '-s', 'bla', 'tmp_link', check : true)
+can_link_symlink = run_command('ln', 'tmp_link', 'tmp_link2', check : false).returncode() == 0
+run_command('rm', '-f', 'tmp_link', 'tmp_link2', check : true)
+message('possible to create a link to a symlink:', can_link_symlink)
+configdata += { 'CAN_LINK_SYMLINK': can_link_symlink.to_int() }
+
+check_headers = [
+  # I can't use dictionaries here as they can only contain identifier-strings.
+  ['aws/s3/S3Client.h', aws_s3]
+]
+
+foreach headerspec : check_headers
+  key = headerspec[0]
+  value = headerspec[1]
+  define_name = 'HAVE_' + key.underscorify().to_upper()
+  define_value = cxx.check_header(key, dependencies : value).to_int()
+  configdata += { define_name: define_value }
+endforeach
+
+check_funcs = [
+  'lchown',
+  'lutimes',
+  'pipe2',
+  'posix_fallocate',
+  'statvfs',
+  'strsignal',
+  'sysconf',
+]
+
+foreach funcspec : check_funcs
+  define_name = 'HAVE_' + funcspec.underscorify().to_upper()
+  define_value = cxx.has_function(funcspec).to_int()
+  configdata += {
+    define_name: define_value,
+  }
+endforeach
+
+has_pubsetbuf = cxx.compiles('''
+  #include <iostream>
+  using namespace std;
+  static char buf[1024];
+  decltype(cerr.rdbuf()->pubsetbuf(buf, sizeof(buf))) _;
+''')
+message('have function "\x1b[1mstd::basic_streambuf::pubsetbuf\x1b[0m" :', has_pubsetbuf)
+configdata += {
+  'HAVE_PUBSETBUF': has_pubsetbuf.to_int(),
+}
+
+boehm = dependency('bdw-gc', required : get_option('enable-gc'))
+if boehm.found()
+  deps += boehm
+endif
+configdata += {
+  'HAVE_BOEHMGC': boehm.found().to_int(),
+}
+
+boost = dependency('boost', required : true)
+deps += boost
+
+cpuid = dependency('libcpuid', required : get_option('enable-cpuid'))
+configdata += {
+  'HAVE_LIBCPUID': cpuid.found().to_int(),
+}
+deps += cpuid
+
+seccomp = dependency('libseccomp', required : get_option('enable-seccomp-sandboxing'))
+configdata += {
+  'HAVE_SECCOMP': seccomp.found().to_int(),
+}
+
+configure_file(
+  configuration : {
+    'PACKAGE_NAME': '"' + meson.project_name() + '"',
+    'PACKAGE_VERSION': '"' + meson.project_version() + '"',
+    'PACKAGE_TARNAME': '"' + meson.project_name() + '"',
+    'PACKAGE_STRING': '"' + meson.project_name() + ' ' + meson.project_version() + '"',
+    'HAVE_STRUCT_DIRENT_D_TYPE': 1, # FIXME: actually check this for solaris
+    'SYSTEM': '"' + host_system + '"',
+  } + configdata,
+  output : 'config.h',
+)
+
+libutil_srcs = [
+  'src/libutil/archive.cc',
+  'src/libutil/args.cc',
+  'src/libutil/canon-path.cc',
+  'src/libutil/cgroup.cc',
+  'src/libutil/compression.cc',
+  'src/libutil/compute-levels.cc',
+  'src/libutil/config.cc',
+  'src/libutil/english.cc',
+  'src/libutil/error.cc',
+  'src/libutil/experimental-features.cc',
+  'src/libutil/filesystem.cc',
+  'src/libutil/git.cc',
+  'src/libutil/hash.cc',
+  'src/libutil/hilite.cc',
+  'src/libutil/json-utils.cc',
+  'src/libutil/logging.cc',
+  'src/libutil/namespaces.cc',
+  'src/libutil/position.cc',
+  'src/libutil/references.cc',
+  'src/libutil/serialise.cc',
+  'src/libutil/source-path.cc',
+  'src/libutil/suggestions.cc',
+  'src/libutil/tarfile.cc',
+  'src/libutil/thread-pool.cc',
+  'src/libutil/url.cc',
+  'src/libutil/util.cc',
+  'src/libutil/xml-writer.cc',
+]
+
+library('nixutil', libutil_srcs,
+  implicit_include_directories : true,
+)
diff --git a/meson.options b/meson.options
new file mode 100644
index 000000000..e14344bdd
--- /dev/null
+++ b/meson.options
@@ -0,0 +1,16 @@
+# vim: filetype=meson
+option('enable-gc', type : 'feature',
+  description : 'enable garbage collection in the Nix expression evaluator (requires Boehm GC)',
+)
+# TODO(Qyriad): is this feature maintained?
+option('enable-embedded-sandbox-shell', type : 'feature',
+  description : 'include the sandbox shell in the Nix bindary',
+)
+
+option('enable-cpuid', type : 'feature',
+  description : 'determine microarchitecture levels with libcpuid (only relevant on x86_64)',
+)
+
+option('enable-seccomp-sandboxing', type : 'feature',
+  description : 'build support for seccomp sandboxing (recommended unless your arch doesn\'t support libseccomp, only relevant on Linux)',
+)
diff --git a/package.nix b/package.nix
index 044021cff..2bce4f291 100644
--- a/package.nix
+++ b/package.nix
@@ -9,6 +9,7 @@
   nlohmann_json,
   bison,
   changelog-d,
+  cmake,
   boost,
   brotli,
   bzip2,
@@ -27,6 +28,8 @@
   mdbook,
   mdbook-linkcheck,
   mercurial,
+  meson,
+  ninja,
   openssl,
   pkg-config,
   rapidcheck,
@@ -132,6 +135,9 @@ in stdenv.mkDerivation (finalAttrs: {
     git
     mercurial
     jq
+    cmake
+    meson
+    ninja
   ] ++ lib.optional stdenv.hostPlatform.isLinux util-linuxMinimal
     ++ lib.optional (!officialRelease && buildUnreleasedNotes) changelog-d;