Validator_ragel: move checkdecoder test from Makefile to scons

src/trusted/validator_ragel/obtain_binutils.py

Index: src/trusted/validator_ragel/obtain_binutils.py
diff --git a/src/trusted/validator_ragel/obtain_binutils.py b/src/trusted/validator_ragel/obtain_binutils.py
new file mode 100755
index 0000000000000000000000000000000000000000..867a682b4b545230d945204f29c47dfa77a17214
--- /dev/null
+++ b/src/trusted/validator_ragel/obtain_binutils.py
@@ -0,0 +1,78 @@
+#!/usr/bin/python

[Nick Bray, 2012/08/08 18:24:44]

Needs copyright header.

[Vlad Shcherbina, 2012/08/09 10:07:35]

Done.

+
+"""
+Usage:
+    %s <objdump> <gas>

[Nick Bray, 2012/08/08 18:24:44]

It doesn't seem like this is really a docstring, if you're interpolating it. 
Drop it down to the main function?

[Vlad Shcherbina, 2012/08/09 10:07:35]

Made it proper docstring instead.

+
+Check out appropriate version of binutils, compile it and
+copy objdump and gas binaries to specified places.
+"""
+
+import sys

[Nick Bray, 2012/08/08 18:24:44]

Alphabetize.

[Vlad Shcherbina, 2012/08/09 10:07:35]

Done.

+import os
+import shutil
+
+CHECKOUT_DIR = '/dev/shm/binutils'
+
+BINUTILS_REPO = 'http://git.chromium.org/native_client/nacl-binutils.git'
+BINUTILS_REVISION = '6993545d5650fa77e75e9ae4b52c5703a53c53cc'
+
+# We need specific revision of binutils, and it have to include the
+# following patches:
+#   Add prefetch_modified - non-canonical encoding of prefetch
+#
+#   Properly handle data16+rex.w instructions, such as
+#   66 48 68 01 02 03 04 data32 pushq $0x4030201
+#
+# We are not using head revision because decoder test depends
+# on precise format of objdump output.
+
+
+def Command(cmd):
+  result = os.system(cmd)

[Nick Bray, 2012/08/08 18:24:44]

I have found that scripts like this benefit from:

print
print "Running: " + cmd
print

So you know what it's doing.

[Vlad Shcherbina, 2012/08/09 10:07:35]

Done.

+  if result != 0:
+    print 'Command "%s" returned %s' % (cmd, result)
+    exit(result)

[Nick Bray, 2012/08/08 18:24:44]

Use sys.exit instead - it is more standard and "exit" appears to be entirely
undocumented.
http://docs.python.org/library/functions.html
I suspect it may not be an official part of the Python API, rather something
from the interpreter loop is leaking in to __builtins__.

[Vlad Shcherbina, 2012/08/09 10:07:35]

Oh, I never suspected that.
Done.

+
+
+def main():
+  if len(sys.argv) != 3:
+    print __doc__ % os.path.split(__file__)[1]
+    exit(1)
+
+  if os.path.exists(CHECKOUT_DIR):
+    shutil.rmtree(CHECKOUT_DIR)
+
+  Command('git clone %s %s' % (BINUTILS_REPO, CHECKOUT_DIR))
+
+  old_dir = os.getcwd()
+  try:
+    os.chdir(CHECKOUT_DIR)
+    Command('git checkout %s' % BINUTILS_REVISION)
+
+    # to please make, set the same modification time

[Nick Bray, 2012/08/08 18:24:44]

Capitalize, period at the end, possibly start the sentence with "Set" and move
the beginning to the end.  Also, why is this an issue?  Comment.

[Vlad Shcherbina, 2012/08/09 10:07:35]

I rechecked, and it's actually not needed. So I removed it altogether.

+    # for all files
+    Command('find . -print0 | xargs -0 touch -r .')
+
+    # they both are required to make binutils,

[Nick Bray, 2012/08/08 18:24:44]

Capitalize, period at end.

[Vlad Shcherbina, 2012/08/09 10:07:35]

Done.

+    # and when they are missing binutils's make
+    # error messages are cryptic
+    Command('flex --version')
+    Command('bison --version')
+
+    Command('./configure')
+    Command('make')
+  finally:
+    os.chdir(old_dir)

[Nick Bray, 2012/08/08 18:24:44]

Why?  The process terminates in this case.  You probably want to finally:
shutil.rmtree(CHECKOUT_DIR), however.

[Vlad Shcherbina, 2012/08/09 10:07:35]

You are right. But I also need to chdir back because objdump and gas target
locations could be relative.

+
+  objdump, gas = sys.argv[1:]
+  shutil.copy(os.path.join(CHECKOUT_DIR, 'binutils', 'objdump'), objdump)
+  shutil.copy(os.path.join(CHECKOUT_DIR, 'gas', 'as-new'), gas)
+
+  shutil.rmtree(CHECKOUT_DIR)
+
+  print 'ok'
+
+
+if __name__ == '__main__':
+  main()