BUG: fix all RPATHs that start with $ORIGIN

When shared libraries are build in a project subdir or in a
subproject, the RAPTH added by meson pointing to the shared library
build directory is not just '$ORIGIN/' but a longer relative path.

Apply the same fix to all RPATHs that start with '$ORING/'.

Fixes mesonbuild#509.

mesonpy/_rpath.py

@@ -26,10 +26,13 @@ def _set_rpath(filepath: Path, rpath: Iterable[str]) -> None:
         subprocess.run(['patchelf','--set-rpath', ':'.join(rpath), os.fspath(filepath)], check=True)
 
     def fix_rpath(filepath: Path, libs_relative_path: str) -> None:
-        rpath = _get_rpath(filepath)
-        if '$ORIGIN/' in rpath:
-            rpath = [('$ORIGIN/' + libs_relative_path if path == '$ORIGIN/' else path) for path in rpath]
-            _set_rpath(filepath, rpath)
+        old_rpath = _get_rpath(filepath)
+        for path in old_rpath:
+            if path.startswith('$ORIGIN/'):
+                path = '$ORIGIN/' + libs_relative_path
+            new_rpath.append(path)
+        if new_rpath != old_rpath:
+            _set_rpath(filepath, new_rpath)
 
 
 elif sys.platform == 'darwin':
@@ -50,9 +53,9 @@ def _replace_rpath(filepath: Path, old: str, new: str) -> None:
         subprocess.run(['install_name_tool', '-rpath', old, new, os.fspath(filepath)], check=True)
 
     def fix_rpath(filepath: Path, libs_relative_path: str) -> None:
-        rpath = _get_rpath(filepath)
-        if '@loader_path/' in rpath:
-            _replace_rpath(filepath, '@loader_path/', '@loader_path/' + libs_relative_path)
+        for path in _get_rpath(filepath):
+            if path.startswith('@loader_path/'):
+                _replace_rpath(filepath, path, '@loader_path/' + libs_relative_path)
 
 else:
 

tests/packages/link-against-local-lib/examplemod.c

@@ -4,7 +4,7 @@
 
 #include <Python.h>
 
-#include "examplelib.h"
+#include "lib/examplelib.h"
 
 static PyObject* example_sum(PyObject* self, PyObject *args)
 {

tests/packages/link-against-local-lib/lib/meson.build

@@ -0,0 +1,9 @@
+# SPDX-FileCopyrightText: 2022 The meson-python developers
+#
+# SPDX-License-Identifier: MIT
+
+example_lib = shared_library(
+    'example',
+    'examplelib.c',
+    install: true,
+)

tests/packages/link-against-local-lib/meson.build

@@ -4,11 +4,7 @@
 
 project('link-against-local-lib', 'c', version: '1.0.0')
 
-example_lib = shared_library(
-    'example',
-    'examplelib.c',
-    install: true,
-)
+subdir('lib')
 
 py = import('python').find_installation()