1 files changed, 74 insertions, 0 deletions
diff --git a/lib/spack/spack/hooks/sbang.py b/lib/spack/spack/hooks/sbang.py
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+++ b/lib/spack/spack/hooks/sbang.py
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+##############################################################################
+# Copyright (c) 2013-2015, Lawrence Livermore National Security, LLC.
+# Produced at the Lawrence Livermore National Laboratory.
+#
+# This file is part of Spack.
+# Written by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
+# LLNL-CODE-647188
+#
+# For details, see https://github.com/llnl/spack
+# Please also see the LICENSE file for our notice and the LGPL.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License (as published by
+# the Free Software Foundation) version 2.1 dated February 1999.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
+# conditions of the GNU General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+##############################################################################
+import os
+
+from llnl.util.filesystem import *
+import llnl.util.tty as tty
+
+import spack
+import spack.modules
+
+# Character limit for shebang line.  Using Linux's 127 characters
+# here, as it is the shortest I could find on a modern OS.
+shebang_limit = 127
+
+def shebang_too_long(path):
+    """Detects whether an file has a shebang line that is too long."""
+    with open(path, 'r') as script:
+        bytes = script.read(2)
+        if bytes != '#!':
+            return False
+
+        line = bytes + script.readline()
+        return len(line) > shebang_limit
+
+
+def filter_shebang(path):
+    """Adds a second shebang line, using sbang, at the beginning of a file."""
+    backup = path + ".shebang.bak"
+    os.rename(path, backup)
+
+    with open(backup, 'r') as bak_file:
+        original = bak_file.read()
+
+    with open(path, 'w') as new_file:
+        new_file.write('#!/bin/bash %s/bin/sbang\n' % spack.spack_root)
+        new_file.write(original)
+
+    copy_mode(backup, path)
+    unset_executable_mode(backup)
+
+    tty.warn("Patched overly long shebang in %s" % path)
+
+
+def post_install(pkg):
+    """This hook edits scripts so that they call /bin/bash
+       $spack_prefix/bin/sbang instead of something longer than the
+       shebang limit."""
+    for file in os.listdir(pkg.prefix.bin):
+        path = os.path.join(pkg.prefix.bin, file)
+        if shebang_too_long(path):
+            filter_shebang(path)
+