build: Fix build and tests on macOS

This commit addresses several compatibility issues that prevented Wayland
from building and passing its test suite on macOS

Core and Compatibility changes:
- Emulate Linux behavior by explicitly setting O_NONBLOCK on connections
  (fixes blocking sendmsg issues on macOS).
- Fix compilation on platforms missing SOCK_CLOEXEC and MSG_CMSG_CLOEXEC.
- Implement wl_os_socket_peercred() using LOCAL_PEERPID for macOS.
- Ensure availability of struct itimerspec (required for POSIX Timers API).

Test suite fixes:
- Add socketpair_cloexec() wrapper to handle platforms without atomic
  SOCK_CLOEXEC support.
- Add implementation of memrchr() for platforms that do not provide it.
- Implement is_debugger_attached() for macOS to handle test timeouts.
- Fix tests to handle Mach-O binary format (instead of ELF).
- Update egl-symbols-check to support macOS *.dylib Mach-O libraries.

Build system:
- Add meson option 'xml_catalog' to allow specifying custom catalog paths.

Signed-off-by: Martin Lopatář <lopin@dataplex.cz>

doc/meson.build

@@ -22,8 +22,16 @@ if vers.version_compare('< 2.26.0')
 	error('Dot (Graphviz) 2.26 or later is required for building documentation, found @0@.'.format(vers))
 endif
 
+run_env = environment()
+if catalog_path != ''
+	if not catalog_path.startswith('/')
+		catalog_path = meson.project_source_root() / catalog_path
+	endif
+	run_env.set('XML_CATALOG_FILES', catalog_path)
+endif
+
 manpage_xsl = 'http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl'
-cmd = run_command(xsltproc, '--nonet', manpage_xsl, check: false)
+cmd = run_command(xsltproc, '--nonet', manpage_xsl, env: run_env, check: false)
 if cmd.returncode() != 0
 	error('The style sheet for man pages providing "@0@" was not found.'.format(manpage_xsl))
 endif

doc/publican/meson.build

@@ -22,6 +22,7 @@ endforeach
 publican_inputs += custom_target(
 	'ProtocolSpec.xml',
 	command: [ xsltproc, '-o', '@OUTPUT@', proto_to_docboox_xsl, '@INPUT@' ],
+	env: run_env,
 	input: wayland_protocol_xml,
 	output: 'ProtocolSpec.xml'
 )
@@ -29,6 +30,7 @@ publican_inputs += custom_target(
 publican_inputs += custom_target(
 	'ProtocolInterfaces.xml',
 	command: [ xsltproc, '-o', '@OUTPUT@', proto_iface_to_docboox_xsl, '@INPUT@' ],
+	env: run_env,
 	input: wayland_protocol_xml,
 	output: 'ProtocolInterfaces.xml'
 )
@@ -39,6 +41,7 @@ publican_inputs += custom_target(
 ClientAPI_combined = custom_target(
 	'ClientAPI-combine-doxygen-files',
 	command: [ xsltproc, '-o', '@OUTPUT@', '@INPUT@' ],
+	env: run_env,
 	input: [ doxygen_Client_combine_xslt, doxygen_Client_index_xml ],
 	output: 'ClientAPI-combined.xml'
 )
@@ -47,6 +50,7 @@ ClientAPI_combined = custom_target(
 publican_inputs += custom_target(
 	'ClientAPI-doxygen-to-docbook',
 	command: [ xsltproc, '-o', '@OUTPUT@', '--stringparam', 'which', 'Client', to_publican_xsl, '@INPUT@' ],
+	env: run_env,
 	input: ClientAPI_combined,
 	output: 'ClientAPI.xml'
 )
@@ -54,6 +58,7 @@ publican_inputs += custom_target(
 ServerAPI_combined = custom_target(
 	'ServerAPI-combine-doxygen-files',
 	command: [ xsltproc, '-o', '@OUTPUT@', '@INPUT@' ],
+	env: run_env,
 	input: [ doxygen_Server_combine_xslt, doxygen_Server_index_xml ],
 	output: 'ServerAPI-combined.xml'
 )
@@ -61,6 +66,7 @@ ServerAPI_combined = custom_target(
 publican_inputs += custom_target(
 	'ServerAPI-doxygen-to-docbook',
 	command: [ xsltproc, '-o', '@OUTPUT@', '--stringparam', 'which', 'Server', to_publican_xsl, '@INPUT@' ],
+	env: run_env,
 	input: ServerAPI_combined,
 	output: 'ServerAPI.xml'
 )
@@ -87,6 +93,7 @@ custom_target(
 		'html',
 		'@INPUT0@'
 	],
+	env: run_env,
 	input: publican_inputs,
 	output: 'html',
 	build_by_default: true,