scons: Pull style hook management out of the main SConstruct.

Put the code which supports style hooks for mercurial and git into two
scons "tools".

Change-Id: I3ffed85a177be4f9e458fff7b1cf16a3a479914e
Reviewed-on: https://gem5-review.googlesource.com/5563
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

5 files changed, 313 insertions, 0 deletions

diff --git a/site_scons/gem5_scons/__init__.py b/site_scons/gem5_scons/__init__.py
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/site_scons/gem5_scons/__init__.py
diff --git a/site_scons/gem5_scons/util.py b/site_scons/gem5_scons/util.py
new file mode 100644
index 000000000..4781cc543
--- /dev/null
+++ b/site_scons/gem5_scons/util.py
@@ -0,0 +1,47 @@
+# Copyright (c) 2013, 2015-2017 ARM Limited
+# All rights reserved.
+#
+# The license below extends only to copyright in the software and shall
+# not be construed as granting a license to any other intellectual
+# property including but not limited to intellectual property relating
+# to a hardware implementation of the functionality of the software
+# licensed hereunder.  You may use the software subject to the license
+# terms below provided that you ensure that this notice is replicated
+# unmodified and in its entirety in all distributions of the software,
+# modified or unmodified, in source code or in binary form.
+#
+# Copyright (c) 2011 Advanced Micro Devices, Inc.
+# Copyright (c) 2009 The Hewlett-Packard Development Company
+# Copyright (c) 2004-2005 The Regents of The University of Michigan
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import sys
+
+import SCons.Script
+
+def ignore_style():
+    """Determine whether we should ignore style checks"""
+    return SCons.Script.GetOption('ignore_style') or not sys.stdin.isatty()
diff --git a/site_scons/site_tools/default.py b/site_scons/site_tools/default.py
index f7eeb28f6..2d32b56bd 100644
--- a/site_scons/site_tools/default.py
+++ b/site_scons/site_tools/default.py
@@ -72,6 +72,8 @@ def common_config(env):
     env.srcdir = env.root.Dir('src')
 
 gem5_tool_list = [
+    'git',
+    'mercurial',
 ]
 
 def generate(env):
diff --git a/site_scons/site_tools/git.py b/site_scons/site_tools/git.py
new file mode 100644
index 000000000..d9f8ab89f
--- /dev/null
+++ b/site_scons/site_tools/git.py
@@ -0,0 +1,118 @@
+# Copyright (c) 2013, 2015-2017 ARM Limited
+# All rights reserved.
+#
+# The license below extends only to copyright in the software and shall
+# not be construed as granting a license to any other intellectual
+# property including but not limited to intellectual property relating
+# to a hardware implementation of the functionality of the software
+# licensed hereunder.  You may use the software subject to the license
+# terms below provided that you ensure that this notice is replicated
+# unmodified and in its entirety in all distributions of the software,
+# modified or unmodified, in source code or in binary form.
+#
+# Copyright (c) 2011 Advanced Micro Devices, Inc.
+# Copyright (c) 2009 The Hewlett-Packard Development Company
+# Copyright (c) 2004-2005 The Regents of The University of Michigan
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import os
+
+import gem5_scons.util
+from m5.util import readCommand
+
+git_style_message = """
+You're missing the gem5 style or commit message hook. These hooks help
+to ensure that your code follows gem5's style rules on git commit.
+This script will now install the hook in your .git/hooks/ directory.
+Press enter to continue, or ctrl-c to abort: """
+
+def install_style_hooks(env):
+    try:
+        gitdir = env.Dir(readCommand(
+            ["git", "rev-parse", "--git-dir"]).strip("\n"))
+    except Exception, e:
+        print "Warning: Failed to find git repo directory: %s" % e
+        return
+
+    git_hooks = gitdir.Dir("hooks")
+    def hook_exists(hook_name):
+        hook = git_hooks.File(hook_name)
+        return hook.exists()
+
+    def hook_install(hook_name, script):
+        hook = git_hooks.File(hook_name)
+        if hook.exists():
+            print "Warning: Can't install %s, hook already exists." % hook_name
+            return
+
+        if hook.islink():
+            print "Warning: Removing broken symlink for hook %s." % hook_name
+            os.unlink(hook.get_abspath())
+
+        if not git_hooks.exists():
+            os.mkdir(git_hooks.get_abspath())
+            git_hooks.clear()
+
+        abs_symlink_hooks = git_hooks.islink() and \
+            os.path.isabs(os.readlink(git_hooks.get_abspath()))
+
+        # Use a relative symlink if the hooks live in the source directory,
+        # and the hooks directory is not a symlink to an absolute path.
+        if hook.is_under(env.root) and not abs_symlink_hooks:
+            script_path = os.path.relpath(
+                os.path.realpath(script.get_abspath()),
+                os.path.realpath(hook.Dir(".").get_abspath()))
+        else:
+            script_path = script.get_abspath()
+
+        try:
+            os.symlink(script_path, hook.get_abspath())
+        except:
+            print "Error updating git %s hook" % hook_name
+            raise
+
+    if hook_exists("pre-commit") and hook_exists("commit-msg"):
+        return
+
+    print git_style_message,
+    try:
+        raw_input()
+    except:
+        print "Input exception, exiting scons.\n"
+        sys.exit(1)
+
+    git_style_script = env.root.Dir("util").File("git-pre-commit.py")
+    git_msg_script = env.root.Dir("ext").File("git-commit-msg")
+
+    hook_install("pre-commit", git_style_script)
+    hook_install("commit-msg", git_msg_script)
+
+def generate(env):
+    if exists(env) and not gem5_scons.util.ignore_style():
+        install_style_hooks(env)
+
+def exists(env):
+    return env.Entry('#.git').exists()
diff --git a/site_scons/site_tools/mercurial.py b/site_scons/site_tools/mercurial.py
new file mode 100644
index 000000000..a38449f43
--- /dev/null
+++ b/site_scons/site_tools/mercurial.py
@@ -0,0 +1,146 @@
+# Copyright (c) 2013, 2015-2017 ARM Limited
+# All rights reserved.
+#
+# The license below extends only to copyright in the software and shall
+# not be construed as granting a license to any other intellectual
+# property including but not limited to intellectual property relating
+# to a hardware implementation of the functionality of the software
+# licensed hereunder.  You may use the software subject to the license
+# terms below provided that you ensure that this notice is replicated
+# unmodified and in its entirety in all distributions of the software,
+# modified or unmodified, in source code or in binary form.
+#
+# Copyright (c) 2011 Advanced Micro Devices, Inc.
+# Copyright (c) 2009 The Hewlett-Packard Development Company
+# Copyright (c) 2004-2005 The Regents of The University of Michigan
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import re
+import sys
+
+import gem5_scons.util
+
+mercurial_style_message = """
+You're missing the gem5 style hook, which automatically checks your code
+against the gem5 style rules on hg commit and qrefresh commands.
+This script will now install the hook in your .hg/hgrc file.
+Press enter to continue, or ctrl-c to abort: """
+
+mercurial_style_upgrade_message = """
+Your Mercurial style hooks are not up-to-date. This script will now
+try to automatically update them. A backup of your hgrc will be saved
+in .hg/hgrc.old.
+Press enter to continue, or ctrl-c to abort: """
+
+mercurial_style_hook_template = """
+# The following lines were automatically added by gem5/SConstruct
+# to provide the gem5 style-checking hooks
+[extensions]
+hgstyle = %s/util/hgstyle.py
+
+[hooks]
+pretxncommit.style = python:hgstyle.check_style
+pre-qrefresh.style = python:hgstyle.check_style
+# End of SConstruct additions
+
+"""
+
+mercurial_lib_not_found = """
+Mercurial libraries cannot be found, ignoring style hook.  If
+you are a gem5 developer, please fix this and run the style
+hook. It is important.
+"""
+
+def install_style_hooks(env):
+    hgdir = env.Dir('#.hg')
+
+    style_hook = True
+    style_hooks = tuple()
+    hgrc = hgdir.File('hgrc')
+    hgrc_old = hgdir.File('hgrc.old')
+    try:
+        from mercurial import ui
+        ui = ui.ui()
+        ui.readconfig(hgrc.abspath)
+        style_hooks = (ui.config('hooks', 'pretxncommit.style', None),
+                       ui.config('hooks', 'pre-qrefresh.style', None))
+        style_hook = all(style_hooks)
+        style_extension = ui.config('extensions', 'style', None)
+    except ImportError:
+        print mercurial_lib_not_found
+
+    if "python:style.check_style" in style_hooks:
+        # Try to upgrade the style hooks
+        print mercurial_style_upgrade_message
+        # continue unless user does ctrl-c/ctrl-d etc.
+        try:
+            raw_input()
+        except:
+            print "Input exception, exiting scons.\n"
+            sys.exit(1)
+        shutil.copyfile(hgrc.abspath, hgrc_old.abspath)
+        re_style_hook = re.compile(r"^([^=#]+)\.style\s*=\s*([^#\s]+).*")
+        re_style_extension = re.compile("style\s*=\s*([^#\s]+).*")
+        old, new = open(hgrc_old.abspath, 'r'), open(hgrc.abspath, 'w')
+        for l in old:
+            m_hook = re_style_hook.match(l)
+            m_ext = re_style_extension.match(l)
+            if m_hook:
+                hook, check = m_hook.groups()
+                if check != "python:style.check_style":
+                    print "Warning: %s.style is using a non-default " \
+                        "checker: %s" % (hook, check)
+                if hook not in ("pretxncommit", "pre-qrefresh"):
+                    print "Warning: Updating unknown style hook: %s" % hook
+
+                l = "%s.style = python:hgstyle.check_style\n" % hook
+            elif m_ext and m_ext.group(1) == style_extension:
+                l = "hgstyle = %s/util/hgstyle.py\n" % env.root.abspath
+
+            new.write(l)
+    elif not style_hook:
+        print mercurial_style_message,
+        # continue unless user does ctrl-c/ctrl-d etc.
+        try:
+            raw_input()
+        except:
+            print "Input exception, exiting scons.\n"
+            sys.exit(1)
+        hgrc_path = '%s/.hg/hgrc' % env.root.abspath
+        print "Adding style hook to", hgrc_path, "\n"
+        try:
+            with open(hgrc_path, 'a') as f:
+                f.write(mercurial_style_hook_template % env.root.abspath)
+        except:
+            print "Error updating", hgrc_path
+            sys.exit(1)
+
+def generate(env):
+    if exists(env) and not gem5_scons.util.ignore_style():
+        install_style_hooks(env)
+
+def exists(env):
+    return env.Dir('#.hg').exists()