1 files changed, 43 insertions, 0 deletions
diff --git a/util/meson_aux/extra-install-cmd.py b/util/meson_aux/extra-install-cmd.py
new file mode 100755
index 0000000..8414847
--- /dev/null
+++ b/util/meson_aux/extra-install-cmd.py
@@ -0,0 +1,43 @@
+#!/usr/bin/env python3
+
+# External command, intended to be called with meson.add_install_script() in meson.build
+
+#                           argv[1]
+# extra-install-cmd.py <aclocal_macrodir>
+
+import os
+import sys
+import subprocess
+
+if not os.getenv('DESTDIR'):
+  # Inform the installer that M4 macro files installed in a directory
+  # not known to aclocal will not be picked up automatically.
+  # (Starting with Python 3.7 text=True is a more understandable equivalent to
+  # universal_newlines=True. Let's use only features in Python 3.5.)
+  result = subprocess.run(['aclocal', '--print-ac-dir'],
+                          stdout=subprocess.PIPE, stderr=subprocess.DEVNULL,
+                          universal_newlines=True)
+  acdir = result.stdout
+  aclocal_path = os.getenv('ACLOCAL_PATH')
+  # acdir and aclocal_path can be sequences of os.pathsep-separated paths.
+  # Merge them to one sequence with leading and trailing os.pathsep.
+  # os.pathsep is ':' for Linux, ';' for Windows.
+  acdirs = os.pathsep
+  if aclocal_path:
+    acdirs += aclocal_path + os.pathsep
+  if acdir:
+    acdirs += acdir + os.pathsep
+
+  if (os.pathsep + sys.argv[1] + os.pathsep) not in acdirs:
+    # f'''.....''' would require Python 3.6. Avoid it.
+    print('''\
+                NOTE
+                ----
+The mm-common Autoconf macro files have been installed in a different
+directory than the system aclocal directory. In order for the installed
+macros to be found, it may be necessary to add the mm-common include
+path to the ACLOCAL_PATH environment variable:
+  ACLOCAL_PATH="$ACLOCAL_PATH:{}"
+  export ACLOCAL_PATH'''.format(sys.argv[1])
+    )
+sys.exit(0)